The value of the nosological distinction between non-affective and affective psychosis has frequently been challenged. We aimed to investigate the transdiagnostic dimensional structure and associated characteristics of psychopathology at First Episode Psychosis (FEP). Regardless of diagnostic categories, we expected that positive symptoms occurred more frequently in ethnic minority groups and in more densely populated environments, and that negative symptoms were associated with indices of neurodevelopmental impairment.plus to estimate five theory-based models of psychosis. We used multiple regression models to examine demographic and context factors associated with symptom dimensions.This study included 2182 FEP individuals recruited across six countries, as part of the EUropean network of national schizophrenia networks studying Gene–Environment Interactions (EU-GEI) study. Symptom ratings were analysed using multidimensional item response modelling in MA bifactor model, composed of one general factor and five specific dimensions of positive, negative, disorganization, manic and depressive symptoms, best-represented associations among ratings of psychotic symptoms. Positive symptoms were more common in ethnic minority groups. Urbanicity was associated with a higher score on the general factor. Men presented with more negative and less depressive symptoms than women. Early age-at-first-contact with psychiatric services was associated with higher scores on negative, disorganized, and manic symptom dimensions.Our results suggest that the bifactor model of psychopathology holds across diagnostic categories of non-affective and affective psychosis at FEP, and demographic and context determinants map onto general and specific symptom dimensions. These findings have implications for tailoring symptom-specific treatments and inform research into the mood-psychosis spectrum. Specifically, FEP individuals were recruited as part of the ‘Functional Enviromics’ work package, which consisted of an incidence and a case-sibling-control study conducted across six countries with the aim to investigate clinical, genetic, and environmental interaction in the development of psychotic disorders.Individuals suffering from their FEP were recruited between 2010 and 2015 as part of the large EUropean network of national schizophrenia networks studying Gene–Environment Interactions (EU-GEI) study ; central Amsterdam, Gouda and Voorhout (the Netherlands); part of the Veneto region, Bologna municipality, city of Palermo ; 20th arrondissement of Paris, Val-de-Marne, Puy-de-Dôme (France); Madrid , Barcelona, Valencia, Oviedo, Santiago, Cuenca (Spain); and Ribeirão Preto (Brazil).et al., We screened all subjects who were referred to mental healthcare services with a suspicion of psychosis. The ascertainment period of cases ranged from 12 months in London to 48 months in Val-de-Marne and Bologna, with a median of 25 months. In each site, a psychiatrist experienced in epidemiology research oversaw the local team, which was centrally trained to minimize non-differential recruitment bias in the different healthcare systems. Written consent was obtained from the subjects who agreed to take part of the case-sibling-control study. For incidence-only cases, local research ethics committees approved the extraction of demographics and clinical information from patient records. More detailed information is available on the EU-GEI core paper on the incidence rates of schizophrenia and other psychotic disorders (Jongsma x.5).Patients were included in the current study if they met the following criteria during the recruitment period: (a) aged between 18 and 64 years; (b) presentation with a clinical diagnosis for an untreated FEP, even if longstanding ; (c) resident within the catchment area at FEP. Exclusion criteria were: (a) previous contact with psychiatric services for psychosis; (b) psychotic symptoms with any evidence of organic causation; and (c) transient psychotic symptoms resulting from acute intoxication . The OPCRIT system allows to: (1) assess the pre-morbid history and current mental state; and (2) establish the diagnosis of psychotic disorders based on algorithms for several diagnostic classification systems. It consists of a checklist which can be filled using different sources, e.g. case records or clinical interviews. Fifty-nine items relate to the mental state examination. We used diagnoses based on Research Diagnostic Criteria (RDC) , omega hierarchical (ωH), and index H. Coefficient ω is an estimate of the proportion of common variance accounted by general and specific symptom dimensions. Coefficient ωH is an estimate of the proportion of reliable variance accounted by the general dimension, treating variability in scores due to specific dimensions as measurement error  the general factor independently from the specific symptom dimensions, and (2) each specific symptom dimension independently from the general factor. To estimate the extent to which symptom dimensions were represented by their own set of OPCRIT items and their replicability across studies, we computed the construct reliability index H , Akaike Information Criterion (AIC), Bayesian Information Criterion (BIC), and Sample-size Adjusted BIC (SABIC) as model fit statistics. For the model showing the best fit, we calculated reliability and strength indices, such as McDonald's omega  analysis in STATA 14  and based on clinical records for 49% (n = 1070) of the sample. The sample prevalence of psychotic symptoms is presented in Supplementary Table S1.We identified 2774 treated incidence cases of psychosis (Jongsma M = 30.1) compared with women . Age-at-first-contact differed across ethnic groups, with individuals of Black ethnicity (M = 29) being younger than individuals of White ethnicity . The most common RDC-based diagnosis was broad or narrow schizophrenia (38.6%), followed by schizoaffective disorders (35%), unspecified non-organic psychotic disorder (16.3%), bipolar disorder (5.9%), and psychotic depression (4.2%).Fifty-seven per cent of FEP were men. Subjects were mostly people of a White ethnicity. Other main ethnic groups included Black African and Black Caribbean, North African, Mixed, and Asian. Mean age-at-first-contact with psychiatric services was 32.1 years; this was lower in men  or case note review (95% CI 0.56–0.65), compared with a classification by chance (95% 0.32–0.41). Moreover, symptom dimensions showed similar diagnostic classification accuracy across countries .Findings on factor scores by gender, age-at-first-contact, and ethnicity, are shown in v. Cambridge), whereas a negative association was observed in Spain (online Supplementary Table S5).A moderate positive association was observed for more densely populated environments and the general dimension score. This is the first study on general and specific symptom dimensions in an incidence sample of psychosis. First, we found in our FEP sample that manic and delusional symptoms primarily underlie the identified general psychosis factor across diagnostic categories of non-affective and affective psychosis. Second, findings showed that specific dimensions of positive, negative, disorganized, manic and depressive symptoms are complementary to the general dimension. Third, general and specific symptom dimensions discriminated well between diagnoses of psychotic disorders. Forth, positive symptoms were more common among individuals of Black and North African ethnicity. Fifth, there was some evidence that early age-at-first-contact was associated with higher scores for several dimensions, such as of negative, disorganised and manic symptoms. Sixth, men presented with more negative and less depressive symptoms than women. Finally, higher scores for the general dimension were observed for individuals living in urban neighbourhoods.et al., et al., et al., et al., et al., et al., v. a multidimensional construct of psychosis. Hence, it was a suitable model for addressing dimensionality issues for psychosis and generating reliable phenotypes.Before interpreting our findings, we must consider potential limitations. Symptoms were rated with a semi-structured face-to-face interview or from case note review. Still, study investigators underwent a specific and centrally organized training for OPCRIT and demonstrated good inter-rater reliability for individual item ratings; moreover, OPCRIT is a tool specifically designed to allow use with different sources (McGuffin et al., et al., et al., et al., et al., In our study, the bifactor model of psychopathology best explained the observed symptoms at FEP compared with unidimensional and multidimensional models. Our findings are consistent with, and extend, previous research on psychotic symptoms in people with enduring psychotic disorders (Reininghaus et al., et al., et al., et al., et al., We found some evidence of gender differences in symptom dimension scores. Men showed less depressive symptoms and more negative symptoms compared with women. This finding is consistent with other studies in stable schizophrenia (Shtasel et al., et al., et al., et al., et al., et al., et al., We further found that symptom dimensions vary in terms of ethnicity. Consistent with a previous report (Kirkbride et al., et al., et al., et al., et al., et al., et al., We showed that high population density is positively associated with the general and specific disorganized, negative and manic dimensions. In our multinational sample, we were not able to replicate previous findings on the relationship between urbanicity and the positive dimension (Kirkbride et al., et al., et al., et al., In the context of a general effort to move away from DSM and ICD categories (Demjaha et al., From a research perspective, our findings suggest that the general dimension may reflect a phenotype for the study of general risk factors. For example, urbanicity may impact on the risk and profile of psychosis through the combination of other, more specific socio- or bio-environmental factors. In addition, we showed a substantial variation of sociodemographic determinants at the specific dimension level, which may support an integrated socio-developmental model of psychosis (Morgan et al., et al., et al., et al., We may further suggest using the general dimension as a quantitative measure of psychopathology for research into the genetic component shared across psychotic disorders. The evidence is required to establish the extent to which pathophysiology of schizophrenia, bipolar disorder, and psychotic depression is shared at the level of pathways and neuronal cell mechanisms (Forstner et al., et al., et al., et al., et al., From a clinical perspective, although each patient presents with a specific pattern of psychopathology and response to treatment at FEP, attention has been traditionally focused on the positive dimension management. Mental health professionals may integrate observations of the whole range of symptoms and signs with a consideration of neurodevelopmental and socio-environmental risk factors. Such an approach should aim to plan and optimize pharmacological and non-pharmacological treatments (Murray We may further suggest promoting mental health professionals to adopt treatment plans guided by dimensions, and increasing their confidence in dimensional classifications. Reconciling contradictory concerns of clinicians and researchers (Kendell and Jablensky,


The incidence of neurological disorders such as multiple sclerosis (MS), Alzheimer’s disease (AD) and Parkinson’s disease (PD) is increasing throughout the world, but their pathogenesis remains unclear and successful treatment remains elusive. Bidirectional communications between the central nervous system and gut microbiota may play some role in the pathogenesis of the above disorders. Up to a thousand bacterial species reside in human intestine; they colonize the gut shortly after birth and remain for life. Numerous studies point to the role of microbiota composition in the development, course and treatment of MS, AD and PD. The purpose of this review is to summarize the current knowledge about the role of gut microbiota composition in the development, course, and prognosis of selected neurological diseases. Global incidence of a number of common neurological disorders is rapidly increasing Bengmark  and consThe central nervous system (CNS) and the gut microbiota interact in a bidirectional manner, e.g. the CNS modulates gut functioning in response to psychological and physical stressors affecting motility, secretion and immune reactivity Mayer , whereas11 bacteria cells can be found in 1 g of colon contents  cells target brain and spinal cord cells leading to demyelination and axonal damage  is the most common neurological disease of young adults in Europe and North America , which is the most widely used animal model of MS, showed that oral treatment with ampicillin, vancomycin, neomycin, sulfate, and metronidazole can delay the onset and reduce the severity of the disease, decrease levels of pro-inflammatory cytokines and increase levels of interleukin (IL)-10 and IL-13  before the induction of EAE resulted in its delayed onset and milder course  is a common neurodegenerative disease of the elderly accounting for 60–80% of all dementia cases , Aβ accumulation in brain and inflammatory response , which are not synthetized by humans    were found in cerebrospinal fluid and the cerebral cortex of patients with general paresis suggesting that these bacteria might play a role in slowly progressive dementia, cortical atrophy, and local amyloidosis  , the second most common neurodegenerative disorder of elderly, is 15 years  consisting of aggregated and phosphorylated α-synuclein (Braak and Del Tredici Non-motor symptoms, including mood and cognitive impairment, sleep disorders, sensory disruption and GI dysfunction (Postuma et al. Prevotellaceae, Coprococcus, Firmicutes, Clostridium coccoides, Clostridium leptum, B. fragilis and increased representation of Lactobacillaceae, Verrucomicrobiaceae, Ruminococcaceae, Lactobacuillus, Bacteroidetes, Proteobacteria, Clostridiaceae and Akkermansia (Hasegawa et al. Lactobacillaceae could affect the ENS as these bacteria were found to increase the excitability of colonic after-hyperpolarization neurons by inhibiting calcium-dependent potassium channel opening (Kunze et al. Lactobacillus spp. quantity and serum leptin concentrations were found to be positively correlated (Queipo-Ortuno et al. Prevotellaceae and increased abundance of Lactobacillaceae have been correlated with decreased levels of gut ghrelin. The latter hormone may regulate nigrostriatal dopamine function and restrict neurodegeneration in PD (Queipo-Ortuno et al. Prevotellaceae levels are not specific for PD and were reported in other diseases such as autistic spectrum disorders (Kang et al. Prevotellaceae levels have been proposed as an excluding biomarker of PD (Scheperjans et al. Prevotellaceae below 6.5% was found to be diagnostic of PD with 86.1% sensitivity and 38.9% specificity (Dinan and Cryan Enterobacteriaceae positively correlate with the severity of postural instability and gait difficulty (Scheperjans et al. Gut microbiota abnormalities are common in PD patients and their relation to brain dysfunction is being intensively investigated (Scheperjans B. fragilis, C. perfringens, Pseudomonas spp., most strains in Enterobacteriaceae family, 12 species in Clostridium, C. coccoides group and C. leptum subgroup (Hasegawa et al. Initial studies employing per os administration of hydrogen water in rats (Fu et al. Akkermansia and Ralstonia were found to be increased in affected patients (Scheperjans Interestingly, small intestinal bacterial overgrowth was found to contribute to the pathophysiology of motor fluctuation in PD patients and eradication of bacterial overgrowth resulted in clinical improvement (Fasano et al. Some authors also found an increase in gut permeability in patients with PD when using the urinary sucralose test (Julio-Pieper et al. There was a 90% decrease of plant fiber intake between 1800 and 1970, while the consumption of calories from animal fat and refined sugar increased four times in this time period (Burkitt et al. There is ample evidence for the existence of communication between CNS, gut and intestinal microbiome (Rhee et al.


Recent efforts in synthetic biology have shown the possibility of engineering distributed functions in populations of living cells, which requires the development of highly orthogonal, genetically encoded communication pathways. Cell-free transcription-translation (TXTL) reactions encapsulated in microcompartments enable prototyping of molecular communication channels and their integration into engineered genetic circuits by mimicking critical cell features, such as gene expression, cell size, and cell individuality within a community. In this review, we discuss the uses of cell-free transcription–translation reactions for the development of synthetic genetic circuits, with a special focus on the use of microcompartments supporting this reaction. We highlight several studies where molecular communication between non-living microcompartments and living cells have been successfully engineered. Current Opinion in Biotechnology 2019, 58:72–80NanobiotechnologyThis review comes from a themed issue on Giovanni Maglia and Wesley R BrowneEdited by Issue and the EditorialFor a complete overview see the Available online 26th December 2018https://doi.org/10.1016/j.copbio.2018.10.006http://creativecommons.org/licenses/by/4.0/).0958-1669/© 2018 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY license  reactions constitute ideal model systems for deducing the rules of network composition, developing new communication pathways between cellular mimics and living cells [Simplified models of biological systems could help identify key molecular parameters and as such have the potential to uncover generalisable concepts. Proteins and other components of the transcription and translation machinery can be extracted from cells as a lysate or purified and reconstituted (PURE) in order to perform gene expression ng cells , and creng cells .In this review, we intend to first summarise the use of TXTL reactions for prototyping and implementation of novel genetic networks. We will discuss how microfluidic technologies and semipermeable microcapsules provide essential tools for cell-free synthetic biology in a context where size, composition, and individuality of the reaction are of particular importance. Finally, we will highlight important contributions of encapsulated TXTL to the development of synthetic communication paths.As the complexity of synthetic gene networks increases, more resources are shared between synthetic circuits and their host. As a result, cells experience a decrease in fitness, which limits their growth and the efficiency of synthetic circuits ••. Furthin vivo applications, leveraging the strong potential of riboregulation [Development of complex genetic circuits requires the use of well-characterised regulatory modules. Cell-free TXTL allows the rapid and thorough testing of new genetic parts thus enabling such characterisation .et al. proposed a method for performing TXTL reaction on a chip in which the gene template DNA was attached to a functionalised surface, first under batch conditions using wheat-germ extract [E. coli cell extract [et al. [et al. are a major technological breakthrough that will facilitate the development of numerous synthetic gene circuits in the future.In contrast with methods using free-floating DNA gene templates, Bar-Ziv  extract , and sub extract ••. The l [et al. ••  or double (water-in-oil-in-water) emulsions in order to study large number of these reactions at a cellular scale.et al., who optimised a cell-free genetic circuit based on an incoherent feedforward topology using fluorescently barcoded droplets in which lysate-based TXTL reactions can take place [Large numbers of TXTL microdroplets in oil with a controlled dispersity are easy to generate, store, and remain stable over hours, which makes them particularly interesting for screening large numbers of parameters influencing TXTL reactions c. This fke place .et al. encapsulated Xenopus egg extract in microdroplets of various size. The authors showed that the extract could undergo several mitotic oscillations, and described the influence of the size of the compartments on the period [et al. investigated the influence of surface-to-volume ratio of microcompartments on the efficiency of lysate-based TXTL, suggesting a deleterious interaction between membrane lipids and translation machinery [The reduced size of microdroplets is particularly interesting to study physical effects such as confinement. Guan e period . Sakamotachinery .et al. showed that noise in transcription reaction in systems displaying reduced diffusion resulted in gene expression bursts, which are likely to occur in cells but are not observable in bulk PURE-based TXTL reactions [Macromolecular crowding effects, which emerge in highly concentrated media such as the cytosol, can be artificially induced in TXTL mixtures using crowding additives inside microdroplets. Molecular crowding has been shown to influence the spatial segregation of biomolecules and kinetics of cell-free TXTL reactions ,48. In aeactions .et al. first implemented lysate-based TXTL reaction in a liposome permeated by haemolysin pores, which enabled the exchange of nutrients and by-products with a feeding solution, resulting in long-term gene expression [et al. tested various transcriptional cascades inside liposomes [et al. implemented a lysate-based TXTL liposome sensitive to osmotic changes via expression of the MscL calcium channel [et al. to serve as containers for the production and intratumoural delivery of a toxin protein [et al. recently described the first liposomes capable of isothermally replicating DNA using self-encoded proteins in PURE system, constituting a major step towards the construction of a true synthetic cell capable of full replication [Given that droplets are intrinsically closed systems, they cannot be utilised for long-term protein expression, nor as analogues of semi-permeable lipid bilayers for mimicking the cell membrane. Noireaux pression . Later, iposomes •• , which induced the production of an enzyme disrupting an ongoing communication between an emitter bacterium (P. aeruginosa) and a receiver bacterium (engineered E. coli), a phenomenon also known as quorum quenching.Schwarz-Schilling bacteria . Each po species  (Figure Cell-free TXTL reactions are becoming an essential tool to prototype novel genetic circuits and can facilitate their integration into living hosts. In combination with microfluidic technologies and the development of novel semipermeable microcapsules, TXTL reactions constitute a unique platform for the study of gene expression and coupling to other cellular processes in a biochemically relevant microenvironment.It has been established that size and confinement have a considerable impact on TXTL reactions ,46. For Current efforts are exploring possibilities to establish communication between artificial and natural systems, working towards therapeutic applications wherein information exchange between living cells are mediated or altered. We anticipate that micro-compartmentalised TXTL—by accelerating the characterisation of novel genetic circuits and orthogonal molecular communication channels—will have a compelling contribution to the field of synthetic biology.Nothing declared.• of special interest•• of outstanding interestPapers of particular interest, published within the period of review, have been highlighted as:


Infantile amnesia, a failure in early childhood to retain episodic memory for long periods, is a paradoxical phenomenon widely accepted as an everyday life fact, but its causes are extensively ignored. Recently, Josselyn and Frankland  proposedAfter Freud and Brill  mentioneRecently, Akers et al.  probed tThe study of McGreevy et al.  shows thLow levels of postnatal neurogenesis can also occur; maternal stress (Belnoue et al., per se. Infantile amnesia possibly allows the retention of only more critical memories, filtering those with a robust emotional component (Richardson et al., Even though higher rates of memory retention in young ages appear to be an adaptive advantage, hippocampal neurogenesis and infantile amnesia are widespread among mammals and are probably adaptive Growing evidence suggests that hippocampal neurogenesis is critical for spatiotemporal contextualization and emotional responses associated with memory processing even in humans (See references in Kempermann et al., AM-C proposed the idea. AM-C, GL-O, and PD wrote the paper. GL-O prepared the figure.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.


Pterosaurs are an extinct group of Mesozoic flying reptiles, whose fossil record extends from approximately 210 to 66 million years ago. They were integral components of continental and marginal marine ecosystems, yet their diets remain poorly constrained. Numerous dietary hypotheses have been proposed for different pterosaur groups, including insectivory, piscivory, carnivory, durophagy, herbivory/frugivory, filter‐feeding and generalism. These hypotheses, and subsequent interpretations of pterosaur diet, are supported by qualitative  and/or quantitative  evidence. Pterosaur dietary interpretations are scattered throughout the literature with little attention paid to the supporting evidence. Reaching a robustly supported consensus on pterosaur diets is important for understanding their dietary evolution, and their roles in Mesozoic ecosystems. A comprehensive examination of the pterosaur literature identified 314 dietary interpretations (dietary statement plus supporting evidence) from 126 published studies. Multiple alternative diets have been hypothesised for most principal taxonomic pterosaur groups. Some groups exhibit a high degree of consensus, supported by multiple lines of evidence, while others exhibit less consensus. Qualitative evidence supports 87.3% of dietary interpretations, with comparative anatomy most common . More speciose groups of pterosaur tend to have a greater range of hypothesised diets. Consideration of dietary interpretations within alternative phylogenetic contexts reveals high levels of consensus between equivalent monofenestratan groups, and lower levels of consensus between equivalent non‐monofenestratan groups. Evaluating the possible non‐biological controls on apparent patterns of dietary diversity reveals that numbers of dietary interpretations through time exhibit no correlation with patterns of publication (number of peer‐reviewed publications through time). 73.8% of dietary interpretations were published in the 21st century. Overall, consensus interpretations of pterosaur diets are better accounted for by non‐biological signals, such as the impact of the respective quality of the fossil record of different pterosaur groups on research levels. That many interpretations are based on qualitative, often untestable lines of evidence adds significant noise to the data. More experiment‐led pterosaur dietary research, with greater consideration of pterosaurs as organisms with independent evolutionary histories, will lead to more robust conclusions drawn from repeatable results. This will allow greater understanding of pterosaur dietary diversity, disparity and evolution and facilitate reconstructions of Mesozoic ecosystems. I.et al., et al., et al., et al., et al., et al., et al., et al., et al., et al., et al., et al., Pterosaurs are an extinct clade of flying Mesozoic reptiles, with a 150‐million‐year fossil record from the Late Triassic to the latest Cretaceous  in their gut and throat (content fossils) are interpreted as direct evidence of diet  and oxygen (18O/16O) ratios from bone apatite and tooth enamel can reveal whether animals inhabited terrestrial or marine environments, allowing some limited dietary inferences to be drawn Preondactylus buffarinii and Quetzalcoatlus northropi and all its descendants  of Scotland has been considered as a basal pterosauromorph et al. i) insectivory: insects and unarmoured terrestrial invertebrates; (ii) piscivory: fish and other nektonic organisms such as cephalopods  carnivory: terrestrial vertebrates (predation and/or scavenging); (iv) durophagy: consumption of organisms with hard shells or armour  herbivory/frugivory: fruits and plant matter; (vi) filter‐feeding on planktonic crustacean, mollusc and/or fish larvae; (vii) generalists: where authors explicitly mention this dietary category.We used seven principal dietary categories: (i) content fossils, including coprolites; (ii) spatiotemporal associations with taxa and/or depositional environments; (iii) ichnofossils; (iv) comparative anatomy; (v) functional morphology; (vi) stable isotope analysis.We assign the evidence used to support dietary interpretations to six categories: ((3)(a)The primary data set for this study is a compilation of interpretations, each comprising a statement regarding the diet of a taxon that either is one of the recognised principal taxonomic groups, or falls within one of those groups. Each interpretation was unambiguously assigned to one dietary category and to one evidence category. Dietary statements without supporting evidence were excluded.Dietary interpretations were compiled from the literature. Publications citing previous interpretations but lacking novel data or reasoning were excluded. One hundred and twenty six publications contained at least one novel dietary interpretation. When a publication identified the same dietary and evidence categories for multiple taxa within the same principal group, this was treated as a single novel interpretation. When a publication provided a single dietary statement for a single group but supported it with more than one evidential category, this was tabulated under each evidence category.Differences in the taxonomic content of principal groups between the phylogenies led to differences in the numbers of identified interpretations. For example, a publication assessing diet for two species from the same principal group in one phylogeny was treated as one interpretation. If these two species then fell within different groups in a different phylogeny, this interpretation was counted twice, once for each group. As a result, 314 interpretations were identified for the Unwin phylogeny, 311 for the Kellner phylogeny and 301 for the Andres phylogeny.Details of interpretations for each phylogeny are included as online Supporting Information (see online Appendix S1).(b)et al. A data set of all pterosaur‐focused publications was compiled to estimate research effort through time, from 1784 to February 2017. The sum of all publications (1828) is likely a slight underestimate.(4)et al., P < 0.05), and therefore a Spearman's rank correlation was used when comparing dietary groups and species counts.Numbers of interpretations for each dietary and evidence category were summed for each principal group. Total percentages of each evidence category were calculated. To investigate possible biological and non‐biological drivers of the diversity of dietary interpretations, numbers of species from each principal group were compared to numbers of assigned dietary categories. More speciose groups are hypothesised to have greater dietary diversity because they exhibit more morphological variation  late 18th and 19th centuries (N = 3 from two publications); (ii) 1900–1969 (N = 17 from eight publications); (iii) 1970–1999 (N = 61 from 22 publications); (iv) 2000–present (N = 233 from 94 publications).To assess changes in dietary consensus through time, dietary interpretations for each principal group were assigned to one of four different stages of pterosaur research history Witton, : (i) latIII.(1)Total numbers of dietary interpretations for each principal group Fig.  show lar(2)There is a large disparity in the numbers of interpretations supported by qualitative  and quantitative  approaches, with the former supporting 87.3% of all interpretations Fig. . Compara(3)N = 16, P = 0.031) .There is a moderate positive correlation between pterosaur species per principal group and dietary categories for respective principal groups when Ornithocheiridae is excluded as an outlier The phylogenetic distributions of dietary interpretations for particular groups are broadly consistent among the three phylogenies . However, ‘basal‐most pterosaurs’ and Rhamphorhynchidae in the Andres phylogeny contain substantially more interpretations than their equivalents in the other phylogenies.(5)P = 0.302)  Fig. A. The nu02) Fig. A. There 02) Fig. A. Publis02) Fig. A. This d02) Fig. A. The nu02) Fig. B. The ea(6)During the 19th century, 0.97% of dietary interpretations were proposed, 5.5% were proposed between 1900 and 1969, 19.7% between 1970 and 1999, and 73.8% since 2000 et al. c. 215–190 Ma) of the UK and Italy   digital reconstructions from ‘mathematical slices’ of specimen illustrations do not support this hypothesis et al., Anurognathids are known from the Middle–Upper Jurassic 161–145 Ma) of Germany, Central Asia and China  ichnofossils Fig. . AnurognBennett, , 2007. SBennett, , 2007. ABennett, . High stBatrachognathus volans and Jeholopterus ningchengensis are known from lacustrine deposits and exhibit slightly recurved teeth c. 215–176 Ma) of Central Europe and Greenland (a)et al., Rhamphorhynchines are from the Middle–Upper Jurassic of Europe and China , and a rhamphotheca at the anterior end of the jaw, possibly for skim‐feeding on fish et al., Scaphognathines are from the Middle–Upper Jurassic of Europe, Asia and Cuba  and albatrosses (Diomedeidae) et al., et al., et al., et al., Basal monofenestratans are from the Middle–Upper Jurassic 165–151 Ma) of China et al., Istiodactylids are from the Lower Cretaceous 130–112 Ma) of the UK and China . The proportional lengths of these bones are reportedly similar to modern chameleons (Chameleonidae), and Liaoxipterus was thus reasoned to have caught insects with the aid of a projectile tongue et al., Ornithocheirids are from Lower–Upper Cretaceous 140–95 Ma) deposits on all continents except Antarctica (a)et al., Pteranodontids are from the Lower–Upper Cretaceous 100–80 Ma) of North America and Europe  possess similarly narrow jaws et al., Nyctosaurus gracilis exhibiting an ‘antler‐like’ head crest  of Mid‐West USA, Mexico and Brazil (a)et al., Pterodactylus species exhibit straight, thin jaws with around 50–70 small, conical teeth  of Germany  et al., Ctenochasmatids are from the Lower–Upper Cretaceous 152–100 Ma) of Argentina, Central and Western Europe, Morocco, and East Asia   Fig. . FunctioPiscivory interpretations are based on comparative anatomy Fig. . Sharp, Pterodaustro exhibit short, rounded teeth in their upper jaws, perhaps for crushing hard‐shelled crustaceans Lonchodectids are poorly known pterosaurs known from the Lower–Upper Cretaceous 140–90 Ma) of China, the UK and Brazil (a)et al., Germanodactylus for example, exhibits edentulous jaw tips and low‐crowned teeth, supposedly for selecting and crushing bivalve and crustacean shells  of Central and Western Europe, USA and Tanzania et al., et al., et al., et al., Dsungaripterids are from the Lower Cretaceous 145–100 Ma) of China, Mongolia and South America et al., et al., Tapejarids are from the Lower–Upper Cretaceous 130–93 Ma) of Brazil, Spain and China et al., Chaoyangopterids are from the Lower Cretaceous 130–112 Ma) of China and Brazil, and had 1–4 m wingspans and ‘scissor‐like’ edentulous jaws et al., et al., Thalassodromids are from the Lower Cretaceous of Brazil 125–100 Ma) et al., et al., Azhdarchids are from the Upper Cretaceous (99–66 Ma) of North America, North Africa, Eastern Europe and Asia Overall, there is limited consensus on diets for most pterosaur groups. Most dietary interpretations are supported by qualitative evidence, most commonly from comparative anatomy. There is strong consensus on diets for some pterosaur groups, such as insectivory in Anurognathidae and piscivory in Ornithocheiridae and Pteranodontidae, supported by one or several evidential categories. For other groups there is little consensus: in both basal ctenochasmatoids and Azhdarchidae, for example, six distinct diets have been suggested. In general, pterosaur principal groups with more species exhibit a higher diversity of dietary hypotheses. Choice of phylogeny has some impact on consensus, with the largest differences observed between phylogenies for non‐monofenestratan groups. Numbers of dietary interpretations exhibit small increases for much of pterosaur research history, with most interpretations proposed in the 21st century. Changes in the number of dietary interpretations through time do not correlate with numbers of pterosaur publications.et al., That the majority of dietary interpretations are qualitative is unsurprising because such interpretations can be readily proposed without rigorous experiments or analyses. Comparative anatomy uses extrapolations from observational, and occasionally experimental, studies of extant organisms Aerts, . Associaet al., i) they often require specialist technology and/or equipment; (ii) they require thorough understanding of experimental design and hypothesis testing; (iii) they can require destructive sampling of specimens et al., The range of methods employed in analysis of pterosaurs has proven highly successful in generating interpretations of diet. What is less clear, however, is how well they have performed in differentiating between alternative interpretations, and this partly explains why, for most pterosaur groups, multiple interpretations have been proposed. Greater use of analytical and experiment‐led methodologies (Veldmeijer (a)et al., Comparative anatomy is fundamental for analysis of homology and character evolution but has limitations as a tool for analysis of function and diet. Its application in this context is based on the assumption that convergence of morphological structures between extant and extinct taxa allows us to infer similar functional roles for structures in extinct taxa, including foraging and feeding ecology et al., Despite the straightforwardness of using associations, deriving dietary interpretations from simple presence and/or absence of contemporaneous fossils amounts to little more than speculation. Likewise, solely examining depositional environments does not account for organism dispersal abilities and taphonomic biases such as carcass transportation (Veldmeijer (c)et al., in vivo data)   crania, for example, found that models which accounted for the heterogeneous nature of material properties in bone across the cranium exhibited fewest discrepancies with experimental outputs , aerial  and aquatic‐based (diving and wading) behaviours can provide new constraints, or corroborate existing constraints, on possible foraging strategies and food‐acquisition behaviours. Locomotory models, however, are heavily influenced by mass estimations Witton, . Greater(d)et al., post mortem artefacts, with items introduced via water flows et al., via alignment of photographs taken from numerous angles 15N and/or δ 13C. In the context of extant animals, isotopic approaches to dietary reconstruction are not without methodological limitations . Analysis of carbon isotopes from tooth enamel is possible, but this is primarily used to infer the relative proportions of C3 and C4 plants consumed et al., et al., Only one study has examined dental wear patterns on pterosaur teeth and used this to infer aspects of diet and the material properties of food Ősi, . Dietaryet al., et al., et al., et al., et al., A more robust approach involves quantitative analysis of the sub‐micron scale 3D surface textures of teeth, known as dental microwear texture analysis  A range of diets have been proposed for pterosaurs including insectivory, piscivory, carnivory, durophagy, filter‐feeding and generalism.(2) Most pterosaur dietary interpretations are supported by qualitative evidence including comparative anatomy, associations, content fossils and ichnofossils with a minority supported by quantitative evidence from functional morphology and isotope analyses.(3) Some pterosaur principal groups exhibit high levels of consensus regarding diet, supported by several evidential categories; others exhibit lower levels of consensus, with different interpretations inferred from conflicting evidence of the same categorical type, and typically poorly constrained analogy drawn from comparative anatomy.(4) More speciose pterosaur groups exhibit higher diversity of hypothesised diets. Whilst this may reflect biological signals such as ecological radiations or niche partitioning, non‐biological causes, such as historical biases in the data, quality of the fossil record and research intensity are more likely. These biases mean it is currently difficult to reliably test the hypothesis that the apparent patterns of pterosaur dietary diversity and disparity are biologically controlled.(5) Examining patterns of dietary diversity using different phylogenies reveals higher consensus among monofenestratan groups and lower consensus in non‐monofenestratan groups. Better resolution on the membership of pterosaur groups would assist in uncovering true diets for respective groups.(6) Numbers of pterosaur publications per year and dietary interpretations do not correlate through time. The majority of interpretations were proposed in the 21st century. The almost exponential rise in the number of publications containing dietary interpretations since the 1980s coincides with discoveries of new Lagerstätten and other exceptionally preserved sites, as well as applications of new techniques to pterosaurs.(7) Many dietary interpretations are based on simple extrapolations and comparisons with modern biology with little scope for testing. Qualitative methods can serve as starting points for generating hypotheses, but quantitative tests provide more robust analyses and insights into dietary diversity, evolution and the ecological roles of pterosaurs. Improvements to current methods and application of novel methods to pterosaurs will provide better constraints on diets in pterosaurs with low levels of consensus, and better tests of dietary hypotheses in pterosaurs with high levels of consensus. This will allow reliable investigations into possible biological signals behind pterosaur dietary diversity and disparity, which will allow greater understanding of pterosaur dietary evolution and facilitate reconstructions of Mesozoic ecosystems.Appendix S1. Breakdowns of all pterosaur dietary interpretations, detailing dietary and evidential category assortments, for each of the Unwin, Kellner and Andres phylogenies. The Kellner and Andres pterosaur phylogenies  and dietary interpretations for each pterosaur principal group  are also included. Further information on phylogenies and the full list of 180 pterosaur species assorted into principal groups from the Unwin phylogeny is also provided.Click here for additional data file.


Dear Editor,A receptor. Therefore, endothelin-1 leads to a narrowing of the liver sinusoids and an increase of portal pressure . TGR5 ial., 2019). MoreovThe prevalence of liver diseases currently increases (Jansen et al., 2017; EkhlasiThe author declares no conflict of interest.


A and GABAB receptors . In immature networks and during numerous pathological conditions the strength of GABAergic synaptic inhibition is much less pronounced. In these neurons the activation of GABAAR produces paradoxical depolarizing action that favors neuronal network excitation. The depolarizing action of GABAAR is a consequence of deregulated chloride ion homeostasis. In addition to depolarizing action of GABAAR, the GABABR mediated inhibition is also less efficient. One of the key molecules regulating the GABAergic synaptic transmission is the brain derived neurotrophic factor (BDNF). BDNF and its precursor proBDNF, can be released in an activity-dependent manner. Mature BDNF operates via its cognate receptors tropomyosin related kinase B (TrkB) whereas proBDNF binds the p75 neurotrophin receptor (p75NTR). In this review article, we discuss recent finding illuminating how mBDNF-TrkB and proBDNF-p75NTR signaling pathways regulate GABA related neurotransmission under physiological conditions and during epilepsy.In the mature healthy mammalian neuronal networks, γ-aminobutyric acid (GABA) mediates synaptic inhibition by acting on GABA A) receptors (GABAARs) causes membrane depolarization and Ca2+ influx in immature neurons , respectively  is ~78–82 mV, close to the resting membrane potential  hyperpolarization or depolarization. The activation of GABAARs during neuronal depolarization induced by the excitatory synapses allows massive Cl− entry that provides strong hyperpolarizing force and effectively compensates or diminishes the strength of the excitatory signal. The increased [Cl−]i is rapidly extruded by electroneutral neuron-specific potassium-chloride cotransporter KCC2  complex which leads to a clathrin-mediated internalization  and PKC pathways , a downstream target of PI-3 kinase  signaling cascade . The surface expression of GABA transporter-1 (GAT-1), the major GABA transporter expressed by both neurons and astrocytes , attributed to the activity of KCC2  and not observed in BDNF KO mice (Fiorentino et al., BRs induce a calcium-dependent release of BDNF via the PLC-PKC signaling cascade and L-type voltage-gated calcium channels (Fiorentino et al., BRs also increased the phosphorylation levels of the α-CamKII, which play a critical role in BDNF release (Fischer et al., B-R-mediated release of BDNF. Interestingly, the regulated secretion of BDNF following GABAB receptor activation increases the number of GABAA ß2/3 subunits receptors at the postsynaptic membrane (Kuczewski et al., BRs activation and the subsequent BDNF secretion in developing hippocampal neurons contribute to the functional maturation of GABAergic synaptic transmission.Similarly to BDNF, a crucial factor regulating the development of inhibitory transmission is GABA itself (Ben-Ari et al., a et al.  demonstr− homeostasis are considered to play a crucial role in epileptogenesis. Initial studies regarding the contribution of BDNF to epilepsy led to conflicting conclusions, with intrahippocampal BDNF perfusion or intraventricular injection of the BDNF scavenger TrkB-IgG, both being protective in a model of dorsal hippocampal kindling (Reibel et al., NTR are markedly increased after Pilocarpine-induced seizures. The elevated amounts of proBDNF following SE are associated with reduced proBDNF cleavage machinery that results from acute decreases in tPA/plasminogen proteolytic cascade and increases in API-1, an inhibitor of proBDNF cleavage (Reibel et al., NTR response following SE selectively downregulates KCC2, which in turn promotes a chloride homeostasis dysregulation leading to an excitatory action of GABAA receptors and facilitate epileptiform discharges (Kourdougli et al., NTR during the earliest phase of epileptogenesis restores KCC2 levels and reduces seizures frequency (Kourdougli et al., NTR play a critical role in the mechanisms of epileptogenesis (see Figure A receptor endocytosis and degradation (Riffault et al., ARs α1 subunit gene through the activation of JAK-STAT pathway following SE (Lund et al., NTR signaling during the first postnatal weeks causing an impaired or delayed functional maturation of GABAergic inhibition. Alternatively, an excess of BDNF production and secretion associated with reductions in proBDNF cleavage in epileptic tissues (Ernfors et al., Epilepsy is a brain disorder characterized by the appearance of spontaneous recurrent seizures due to network hyperexcitability (Fischer et al., Unveiling the mode of action of BDNF in the development and functioning of the GABAergic network is a promising quest for developing new cures of a number of neurological diseases. BDNF influences the development and functioning of the GABAergic network which in turn controls BDNF levels. As a result of this interaction, impairment of one of the two systems will most disturb the other, and since each of them is fundamental to normal CNS functioning, this will potentially lead to a host of neurological conditions. As of today, there is hope that investigation of the molecular pathways mediating the trophic action of BDNF may provide new insights into the normal development of the GABAergic network, providing new therapeutic strategies to improve the symptoms in a broad spectrum of GABA-related pathologies.The review was conceptualized, written and edited by each of the authors. CP was the supervisor.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.


The cerebellum plays a critical role in coordinating and learning complex movements. Although its importance has been well recognized, the mechanisms of learning remain hotly debated. According to the classical cerebellar learning theory, depression of parallel fiber synapses instructed by error signals from climbing fibers, drives cerebellar learning. The uniqueness of long-term depression (LTD) in cerebellar learning has been challenged by evidence showing multi-site synaptic plasticity. In Purkinje cells, long-term potentiation (LTP) of parallel fiber synapses is now well established and it can be achieved with or without climbing fiber signals, making the role of climbing fiber input more puzzling. The central question is how individual Purkinje cells extract global errors based on climbing fiber input. Previous data seemed to demonstrate that climbing fibers are inefficient instructors, because they were thought to carry “binary” error signals to individual Purkinje cells, which significantly constrains the efficiency of cerebellar learning in several regards. In recent years, new evidence has challenged the traditional view of “binary” climbing fiber responses, suggesting that climbing fibers can provide graded information to efficiently instruct individual Purkinje cells to learn. Here we review recent experimental and theoretical progress regarding modulated climbing fiber responses in Purkinje cells. Analog error signals are generated by the interaction of varying climbing fibers inputs with simultaneous other synaptic input and with firing states of targeted Purkinje cells. Accordingly, the calcium signals which trigger synaptic plasticity can be graded in both amplitude and spatial range to affect the learning rate and even learning direction. We briefly discuss how these new findings complement the learning theory and help to further our understanding of how the cerebellum works. It is widely recognized that the cerebellum is critical in coordinating muscles and learning novel movements with highly accurate and temporal precision. Even for a simple finger-to-nose task, to make different segments of hand and arm interact smoothly, humans need the cerebellum to precisely modulate the sequence and duration of elementary movements. The cerebellum has a relatively simple anatomy and the anatomic connections involved in its associated functions are also well known. In this context, the cerebellum becomes an ideal structure to explore learning rules and it also opens a window for us to begin to comprehend how the brain works.via excitatory synaptic connections. Small granule cells are electrically compact and they constitute the majority of neurons in the brain. Their axons project up into the molecular layer of the cerebellar cortex, bifurcate and form excitatory synapses onto Purkinje cell dendrites. As the sole output of the cerebellar cortex, each Purkinje cell is contacted by ~150,000 parallel fiber (bifurcations of granule cell axons) synapses. Meanwhile, parallel fibers also activate stellate cells and basket cells, which form inhibitory synapses with Purkinje cells, establishing a stereotypical feed-forward-inhibition circuit. Stellate cells tend to locate in the outer part of the molecular layer and mainly target Purkinje cell distal dendrites. In contrast, basket cells locate in the inner part of the molecular layer and mainly target Purkinje cell somas and axon initial segments (AIS).For decades, it has been of great interest to decipher cerebellar learning algorithms , adds to the confusion. In a recent experimental data-based theoretical study by Zang et al. (+ channels, and dendritic spike patterns.On one hand, a growing body of experimental evidence demonstrates the variability of climbing fiber responses, but on the other hand, it fails to provide a systematic explanation of somatic and dendritic spike initiation and variation and leads to many conflicting observations that stymie delineation of the functional role of climbing fibers in cerebellar learning. Furthermore, limited information extracted from noisy g et al. , the biog et al. . The som2+ influx can be graded by climbing fiber firing patterns, coincident background synapses, and voltage states in an analog manner. The conflicting spatial range of Ca2+ influx observed in different experiments can be accounted for by different voltage states (Miyakawa et al., 2+ channels, but also voltage-dependent K+ channels. Climbing fibers directly excite and depolarize proximal smooth dendrites (Palay and Chan-Palay, 2+ channels. When dendritic membrane potential is hyperpolarized, the large availability of K+ currents outweighs P-type Ca2+ current to “brake” the initiation of dendritic spikes in distal parts. With depolarization, K+ currents inactivate and axial currents can trigger dendritic spikes in the whole dendrite. Theoretically, voltage-dependent climbing fiber responses also endow single Purkinje cells with the ability to overcome the credit assignment problem. Individual Purkinje cells can extract specific instruction information according to their firing states (equivalent to voltage states in vivo; Jelitai et al., In agreement with Ohtsuki et al.  and Otsu2+ influx is larger than spontaneous Ca2+ spikes to signal the occurrence of an unexpected sensory event. Furthermore, Ca2+-based instruction signals in Purkinje cell dendrites contain analog information that encodes the strength of instructive stimuli trial-by-trial (Najafi et al., 2+ influx in Purkinje cells. Extracellular microelectrodes are usually used to extract simple spikes and complex spikes in vivo. Nonetheless, complex spike patterns are extremely variable in spikelet numbers and durations (Warnaar et al., in vivo noise. Thus, it is easier to sort complex spikes from Purkinje cells with low firing rates compared to Purkinje cells with high firing rates, and this causes unavoidable bias in statistical analyses. Sometimes, it is even impossible to separate a complex spike with its subsequent simple spike, when the complex spike lacks a significant pause. This situation mainly occurs when there is only one dendritic spikelet that fails to hyperpolarize dendrites (see Figure 6A in Davie et al., 2+ influx (Zang et al., Although Purkinje cells and climbing fibers are capable of encoding analog signals, does this really contribute to cerebellar learning? As reported by Najafi et al. , sensoryNoticeably, theoretical studies have also started to test the role of graded climbing fiber responses in cerebellar learning. Using a cerebellar network model with necessary climbing fiber-evoked burst-pause information in Purkinje cells (different with parallel fiber-evoked burst-pause by Steuber et al., 2+ induction threshold, usually with a climbing fiber as the polarity switch (2+ influx relative to the threshold, regardless of concurrent climbing fiber signals (Parallel fiber synapses exhibit bidirectional long-term plasticity (Coesmans et al., y switch . Howevery switch , and LTDy switch . Mathy ey switch  requiredy switch . Pooling signals . In the  signals . Nonethe signals . The aut signals  demonstr signals  and ther signals . In a mo signals  demonstr2+ influx and consequently shifts plasticity from LTD to LTP.Although LTD is demonstrably critical in cerebellar learning, at least in some behavioral contexts, there is increasing awareness that it is not the sole mechanism. Accumulating evidence demonstrates that LTP of parallel fiber synapses also functions in procedural learning (Schonewille et al., 2+ influx is constrained to proximal dendrites in Purkinje cells showing decreased firing rates, as observed in vitro (Zagha et al., 2+ influx is still global in Purkinje cell dendrites, is it within the range of triggering LTP rather than LTD? In other words, does the directional change of Purkinje cell simple spike firing rates determine the polarity of parallel fiber synaptic strength changes, with LTD in “bursting” Purkinje cells, but LTP in “pause” Purkinje cells?In cerebellum-related behaviors such as saccadic eye movement (Herzfeld et al., 2+ threshold-dependent plasticity rule (Coesmans et al., A recent study proposed synaptic plasticity rules that strikingly contradict the current consensus of plasticity induction to solve the credit assignment problem (Bouvier et al., 2+ influx determines the computational unit of climbing fiber responses and constrains the learning capacity of individual Purkinje cells. Although Ca2+ influx due to strong parallel fiber-triggered dendritic spikes is constrained to branchlets (Hartell, 2+ signals was first shown to increase with distance from the soma in anesthetized rats (Kitamura and Hausser, 2+ channels with distance from the soma. In the physiologically detailed Purkinje cell model with homogeneous distributed Ca2+ channels, dendritic Ca2+ influx increases significantly with distance from the soma and shows significant variations in different branchlets at similar distances (Zang et al., in vivo, including firing state-related availability of K+ channels, concurrent synaptic input and compartment-specific dendritic excitability plasticity (Kitamura and Hausser, 2+ influx implies that both LTP and LTD can occur coincidently at different dendritic branchlets of a Purkinje cell. This spatio-temporal variability can be fine-tuned to modulate the distribution of branchlet-specific synaptic changes, rather than a homogeneous change. Accordingly, the learning capacity of single Purkinje cells can be significantly increased, which may be necessary for complex and arbitrary movement learning (Bouvier et al., Conventionally, dendritic trees are thought to just receive synaptic inputs from presynaptic cells and to convey them to the soma. In recent years, more and more experimental data have uncovered local computation in neuronal dendrites (Branco and Häusser, Hartell, , informaIn contrast to the idea of climbing fibers as teachers in the Marr-Albus-Ito theory, an alternative view of their role is to provide a “motor clock” function in the initiation and timing of movements (Welsh et al., via complex spikes (Tang et al., Is there any connection between the “motor clock” signal and instruction signal? The finding by Mathy et al.  of climbDespite the growing awareness of multisite learning (Gao et al., YZ wrote the initial draft and revised it. ED edited the draft and revised it.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.


Al3+ has lethal effects on many aspects of the rhizobia/legume symbiosis, which include a decrease in root elongation and root hair formation, lowered soil rhizobial population, and suppression of nitrogen metabolism involving nitrate reduction, nitrite reduction, nitrogenase activity and the functioning of uptake of hydrogenases (Hup), ultimately impairing the N2 fixation process. At the molecular level, Al is known to suppress the expression of nodulation genes in symbiotic rhizobia, as well as the induction of genes for the formation of hexokinase, phosphodiesterase, phosphooxidase and acid/alkaline phosphatase. Al toxicity can also induce the accumulation of reactive oxygen species and callose, in addition to lipoperoxidation in the legume root elongation zone. Al tolerance in plants can be achieved through over-expression of citrate synthase gene in roots and/or the synthesis and release of organic acids that reverse Al-induced changes in proteins, as well as metabolic regulation by plant-secreted microRNAs. In contrast, Al tolerance in symbiotic rhizobia is attained via the production of exopolysaccharides, the synthesis of siderophores that reduce Al uptake, induction of efflux pumps resistant to heavy metals and the expression of metal-inducible (dmeRF) gene clusters in symbiotic Rhizobiaceae. In soils, Al toxicity is usually ameliorated through liming, organic matter supply and use of Al-tolerant species. Our current understanding of crop productivity in high Al soils suggests that a much greater future accumulation of Al is likely to occur in agricultural soils globally if crop irrigation is increased under a changing climate.Recent findings on the effect of aluminium (Al) on the functioning of legumes and their associated microsymbionts are reviewed here. Al represents 7% of solid matter in the Earth’s crust and is an important abiotic factor that alters microbial and plant functioning at very early stages. The trivalent Al (Al Legumes, therefore, play a major role in reducing poverty, improving human health and nutrition and enhancing ecosystem functioning. With more than 78.3 million ha of land planted to legumes, these species provide over 35% of the world’s protein intake  by legumes is therefore a major source of N for agriculture  stress 2+, Al(OH)2+, Al(OH)3 and Al(OH)4− 2+ and Al(OH)2+ species are formed as the soil pH increases 4−] dominates under alkaline conditions  and phosphoenol pyruvate carboxylase (PEPC), which catalyse the formation of carboxylic acids  and Cd (0.3–0.5 mM)  gene clusters have been discovered in Rhizobium leguminosarum bv. viciae and other members of the Rhizobiaceae that are expressed in response to heavy metal concentrations  . We postulate that organic acids (OAs) secreted by roots and cluster roots chelate with active Al to form inactive complexes in the rhizosphere. We also suggest that these OAs inside roots and cluster roots form complexes with incoming active Al ions to form inactive Al-OA complexes that are stored in non-toxic forms in roots and cluster roots. This model could explain why the Al concentrations in below-ground organs such as roots and cluster roots are many folds greater than Al levels in above-ground shoots. In our view, this constitutes the mechanism by which A. linearis can thrive in Al-rich, highly acidic soils in the Cape Fynbos of South Africa. Taken together, these biochemical subtleties in Al tolerance support A. linearis as a natural system for studying metal tolerance in nodulated perennial legumes  the selection and use of legume/rhizobia symbioses resistant to metals, (ii) the use of mixed inoculants containing metal-resistant rhizobia and plant growth-promoting rhizobacteria and (iii) plant inoculation with a mixture of rhizobia and mycorrhizae (Pajuelo et al. Furthermore, the ability of legumes such as 2 fixation of A. linearis (Muofhe and Dakora Interestingly, while there is evidence of acid-tolerant genes in symbiotic rhizobia (Dilworth et al. 2+ to overcome inhibition of root elongation by Al. Thus, even though tap roots might extend into acidic soil zones, development of lateral roots for nutrient and water capture could still be limited (Ferrufino et al. Al phytotoxicity can be amended through liming with calcium carbonate, addition of organic matter and/or by use of Al-tolerant species (Mokolobate and Haynes + and Al+3 activities (Sanzonowicz et al. +3 activity at root cell plasma membrane, thus preventing the disruption of cell expansion and cell division commonly induced by Al toxicity (Kochian Liming has also been found to increase Ca availability to rhizobia and the symbiosis (Hungria and Vargas  Kochian . Similar Kochian . Applied Kochian .Organic matter can also be used to overcome Al toxicity in plants and microbes Foy . During 2 fixation and decreased crop yield. Therefore, selecting legume/rhizobia symbioses that are tolerant of Al toxicity is the easiest way to increase crop yields in Al-rich acidic soils. A better understanding of legume exudation in response to Al toxicity and the mechanisms underlying rhizobial tolerance of Al stress is crucial for increasing yield of grain and pasture legumes. Furthermore, understanding gene expression in the presence of added Al may be a strategy for identifying rhizobial genes and legume traits that permit high N2 fixation in the presence of Al stress.Taken together, Al stress is a major abiotic factor affecting plant growth and productivity. With 40% of the world’s arable land consisting of acid soils and Al toxicity being associated with low pH, global legume production is likely to be hugely constrained. This is because Al toxicity in soils can inhibit root elongation, lateral root development, root hair growth, rhizobial infection of the roots, Nod factor production and nodule development, resulting in low N


ARs) are the major mediators of synaptic inhibition in the brain. Aberrant GABAAR activity or regulation is observed in various neurodevelopmental disorders, neurodegenerative diseases and mental illnesses, including epilepsy, Alzheimer’s and schizophrenia. Benzodiazepines, anesthetics and other pharmaceutics targeting these receptors find broad clinical use, but their inherent lack of receptor subtype specificity causes unavoidable side effects, raising a need for new or adjuvant medications. In this review article, we introduce a new strategy to modulate GABAeric signaling: targeting the intracellular protein interactors of GABAARs. Of special interest are scaffolding, anchoring and supporting proteins that display high GABAAR subtype specificity. Recent efforts to target gephyrin, the major intracellular integrator of GABAergic signaling, confirm that GABAAR-associated proteins can be successfully targeted through diverse molecules, including recombinant proteins, intrabodies, peptide-based probes and small molecules. Small-molecule artemisinins and peptides derived from endogenous interactors, that specifically target the universal receptor binding site of gephyrin, acutely affect synaptic GABAAR numbers and clustering, modifying neuronal transmission. Interference with GABAAR trafficking provides another way to modulate inhibitory signaling. Peptides blocking the binding site of GABAAR to AP2 increase the surface concentration of GABAAR clusters and enhance GABAergic signaling. Engineering of gephyrin binding peptides delivered superior means to interrogate neuronal structure and function. Fluorescent peptides, designed from gephyrin binders, enable live neuronal staining and visualization of gephyrin in the post synaptic sites with submicron resolution. We anticipate that in the future, novel fluorescent probes, with improved size and binding efficiency, may find wide application in super resolution microscopy studies, enlightening the nanoscale architecture of the inhibitory synapse. Broader studies on GABAAR accessory proteins and the identification of the exact molecular binding interfaces and affinities will advance the development of novel GABAAR modulators and following in vivo studies will reveal their clinical potential as adjuvant or stand-alone drugs.γ-aminobutyric acid type A receptors (GABA ARs) are the principal mediators of phasic and tonic inhibition in the human brain, being a vital part of the molecular machinery that creates cognition, behavior, and consciousness  domain carrying proteins. These showed that through modulation of receptor-scaffolding protein interactions a variety of responses could be achieved, ranging from disruption of glutamate signaling to neuroprotective effects in ischemic brain damage  is a guanine nucleotide exchange factor for Cdc42, a gephyrin binding partner (Kins et al., AR subtypes and GABAAR scaffolds. Neuroligin dysfunction has been implicated in autism (Pettem et al., AR, remain uncharacterized. These molecular insights could greatly contribute to our understanding of the development of the inhibitory synapse, as well as the underlying molecular causes of developmental diseases. Neuroligin family members exert distinct roles in the formation and stabilization of inhibitory and excitatory synapses and display distinct cellular and subcellular distributions. Accordingly, molecules that interfere with their isoform-specific interactions could act as highly cell-type selective modulators of neurotransmission.Proteomic studies (Kang et al., ARs. The loss of gephyrin clusters following the loss of the GABAAR γ2 subunit (Essrich et al., AR clusters upon gephyrin deficiency (Kneussel et al., AR subunits could be confirmed (Tretter et al., in-silico studies (Pennacchietti et al., AR complexes and demonstrated that at least the GABAAR α1–3 and GlyR β subunits bind to an overlapping site within gephyrin in a mutually exclusive fashion (Maric et al., ARs and GlyRs (Specht et al., Gephyrin is a prime candidate for the role of master regulator of neuronal function at inhibitory sites (Tyagarajan and Fritschy, AR diffusion and contributing to input-specific adaptations at postsynaptic sites (Chen et al., AR synapse dynamics remain to be explored in a comprehensive approach that includes an extensive alternative splicing and complex post-translational modification patterns of this region. Identification of the targeted binding pockets and insights into the binding affinities of the modified and unmodified peptide regions within the central region of gephyrin could shed light on the enigmatic molecular mechanisms of gephyrin multimerization, degradation and the tuning of its ligand binding affinities. Additionally, gephyrin isoforms are tissue-specific (Paarmann et al., Gephyrin itself is dynamically regulated, affecting GABAvia gephyrin was achieved more than a decade ago using intrabodies (Zacchi et al., ARs. One such example is artemisinins [AR signaling. Kasaragod et al. (ARs clustering, making artemisinins the first small molecule lead compounds for a new class of inhibitory neurotransmission modulators. Strikingly, the druggable artemisinin-binding pocket overlaps with the universal receptor binding region of gephyrin, which is critical for the interaction with GABAA and glycine receptors (Kasaragod et al., A and glycine receptors that bind to gephyrin. Biomimetic optimization of the “hotspots” amino acid sequence, enhanced the affinity of the resulting peptide ligands 46,000-fold compared to the corresponding native peptides (Maric et al., in vitro applications of these new super binder peptide reduced GABAAR α2 conductivity and clustering, providing evidence that GABAAR-associated proteins can be successfully targeted with modified peptides to modulate fast synaptic inhibition (Maric et al., Gephyrin’s crucial role in glycinergic and GABAergic transmission made it a major pharmacological target. The modulation of synaptic responses d et al.  identifiAR trafficking is pivotal for the plasticity (Luscher et al., AR cycling is involved in various neurological disorders (Smith and Kittler, AR sites, that are involved in the trafficking of the receptors, has been identified to control receptor numbers and their concentration at synaptic sites (Comenencia-Ortiz et al., AR trafficking, endocytosis, degradation or recycling, is a promising pharmacological strategy. The proposed direct protein interactors are numerous, among them are muskelin (Heisler et al., GABAAR interaction rapidly modulates synaptic GABAAR numbers, inhibitory synaptic strength, neuronal excitability, and notably, affects animal behavior (Kittler et al., AR subunits (AR derived peptides, that effectively compete with AP2 binding, were successfully used to block the receptor internalization in hippocampal neurons, increasing surface concentration of GABAAR clusters by 50% (Smith et al., AR interactions with its intracellular trafficking partners is an alternative way to influence GABAergic signaling.The AP2-GABAsubunits . Short GAR clustering, like artemisinins or “super binding peptides,” could reduce the GABAAR synaptic concentration and function. On the other hand, peptides hampering receptor interaction with AP2 trafficking protein increased the synaptic receptor levels. In theory, these approaches could be applied together to achieve bi-directional modulation of inhibitory neurotransmission, promoting a shift in the dynamic equilibrium from phasic to tonic neuronal response.Ongoing research uncovered original, seemingly contrasting, strategies of GABAergic signaling modulation. On the one hand, ligands disrupting gephyrin-GABAAR associated scaffold or trafficking proteins could be applied wherever abnormal GABAergic activity or regulation is involved in pathogenesis. In status epilepticus patients develop a time-dependent pharmacoresistance to GABAergic agents, probably, due to GABAAR internalization (Naylor et al., ARs (Nicholson et al., ARs and both could potentially be alleviated by targeting GABAAR-associated proteins. Stabilization of the gephyrin-receptor scaffolds at inhibitory postsynapses with molecules that mimic the stabilizing action of CB (Saiepour et al., AR loss and preserve inhibitory neurotransmission, alternatively, applying AP2 inhibitors could reduce GABAAR internalization and reverse the loss of postsynaptic GABAARs. Those examples illustrate the potential of GABAergic modulators as adjuvants ameliorating the effect of existing potent drugs, whereas in epilepsy or other diseases involving deregulation of inhibitory neurotransmission they could be applied as stand-alone therapeutics.Those new strategies of GABAergic neurotransmission modulation possess an untapped clinical potential. Agents targeting GABAAR intracellular interactors, accelerated by in-silico predictions and high throughput approaches, will lead to the discovery of novel GABAergic modulators. Affinity, selectivity, bioavailability and immunogenicity of these compounds would have to be optimized for clinical applications, where peptide-based ligands could be further evolved by the introduction of unnatural amino acids, cyclization and other chemical modifications.We expect that the study of GABAMicroscopy is an additional intriguing application of these molecules. The enhanced affinity and specificity of the engineered peptide-based compounds allowed to pioneer their use as fluorescent probes [AR associated proteins could prove to be a versatile pharmacological strategy with clinical potential. Further, we suggested that when combined with state-of-the-art super-resolution microscopy methods, the peptide-based fluorescent probes may resolve the nanoscale architecture of synapses in unprecedented detail. We anticipate that the discovery of additional GABAAR interactors could open the way for the development of new imaging tools and alternative pharmacological approaches.Here, we discussed how the targeting of GABAVK and HM wrote the manuscript and prepared the figures.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.


In a recent study, Tuuli Karhu and colleagues from Helsinki University compared a set of cell lines for their susceptibility towards eight GATA4 targeting compounds . GATA4 al., 2018; Kikuchial., 2018; Pikkaraal., 2018). The goal., 2018). Of couIn recent years, the development of stem cell based test systems has been a major focus of research (Leist et al., 2017; Godoy ein vivo relevance still remains a major challenge.This approach has been used for developmental neurotoxicity (Waldmann et al., 2014; Meganat


Following systematic scrutiny of the evidence in support of the hypothesis that the cardioprotective mechanism of action of dexrazoxane is mediated by a ‘depletion’ or ‘downregulation’ of Top2β protein levels in heart tissue, the author concludes that this hypothesis is untenable. In seeking to understand how dexrazoxane protects the heart, the outcomes of a customised association rule learning algorithm incorporating the use of antecedent surrogate variables  reveal a previously unknown relationship between dexrazoxane and poly(ADP-ribose) (PAR) polymer. The author shows how this previously unknown relationship explains both acute and long-term cardioprotection in patients receiving anthracyclines. In addition, as a direct inhibitor of PAR dexrazoxane has access to the epigenome and this offers a new insight into protection by dexrazoxane against doxorubicin-induced late-onset damage . Notably, through this review article, the author illustrates the practical application of probing natural language text using an association rule learning algorithm for the discovery of new and interesting associations that, otherwise, would remain lost. Historically, the use of CEME enabled the first report of the capacity of a small molecule to catalyse the hybrid self-assembly of a nucleic acid biopolymer via canonical and non-canonical, non-covalent interactions analogous to Watson Crick and Hoogsteen base pairing, respectively. Dexrazoxane (ICRF-187)  belongs  et al throughout the 1970s and 1980s .−3 = μM) with concentrations in ex vivo tissue mass (μmol kg−1), then using the literature values of IC50 as a measure of toxicity, it can be concluded that for prolonged periods the cardiac concentrations of doxorubicin are sufficient to negatively impact upon cardiomyocyte viability. The limited animal data suggest that cardiotoxic levels of doxorubicin remain significantly above the median IC50 value of 1.67 μM (see above) for at least 24 hours and decline below this limiting concentration between 24 and 48 hours. In both animals and patients, there is convincing evidence for long-term (days/weeks) retention of doxorubicin within cardiac tissue. Accordingly, given the long-term accumulation of doxorubicin within the heart, if the short pre-administration single infusion of dexrazoxane exerts a cardioprotective effect by depleting Top2β protein, then by necessity suppression of the level of Top2β protein within the heart must be profound and long lasting. As the author argues, this seems a remote prospect given that by comparison with the slow elimination of doxorubicin, dexrazoxane has a remarkably short half-life. The logical corollary of this substantial difference in pharmacokinetics is twofold. First, dexrazoxane must exert long-lasting suppression that results in maintenance of Top2β protein below threshold. Second, in the absence of long-lasting suppression, recovery of suppressed Top2β protein (transcription) must be slow.Accepting the proportionality error in comparing concentrations in an aqueous buffer  (t1/2 of 9.3 hours), and to the final hydrolysis product ADR-925 (t1/2 of 23 hours) . Despite the plethora of drugs that degrade Top2β protein, dexrazoxane remains the only product that is licenced for the prevention of cardiotoxicity associated with the use of anthracyclines;  et al  ] , and as  et al  triggered the formation of a supramolecular self-assembly consisting of non-covalent interactions between polyacrylate-anchored melamine units and monomeric cyanuric acid.Cyanuric acid catalyses the formation of supramolecular self-assemblies of a naturally occurring adenine-containing nucleotide, polyadenine (poly(A)), in both its DNA and RNA forms; structurally, poly(A) is closely related to PAR. Cyanuric acid-catalysed self-assemblies of poly(A) can be modelled using either canonical Watson–Crick base pairing or a combination of both canonical Watson–Crick and non-canonical Hoogsteen base pairing. Spectral studies suggest that the preferred assembly of poly(A) strands with cyanuric acid monomers is a coiling triplex formation consisting of both canonical and non-canonical base pairing.Cyanuric acid-catalysed self-assembly using a synthetic adenine-containing peptide nucleic acid (PNA) in place of poly(A) has also been demonstrated.Intuitively, it is to be expected that low-energy conformations will exist when there is a maximum separation between the piperazine structures. Conformational analysis undertaken by the author (for details of methods see the appended Supplement) confirm that lower energy conformations are consistent with the maximum spacing between piperazine structures with each adopting a half-chair conformation at methylene carbon atoms 3,5 of each ring structure resulting in an elevated tertiary amine nitrogen atom. As a half-chair conformation, the remainder of the piperazine structure is planar with the keto group at the carbon atom in position 2 of each ring structure in alignment with the tautomeric nitrogen of the secondary amine group of the adenine base of each ADP-ribose unit of PAR , a pilot study was undertaken by the author to investigate the interaction between dexrazoxane and PAR. Using isolated rat liver mitochondria, we demonstrated for the first time that dexrazoxane inhibits PAR-induced release of AIF. Although the details of this methodology are not presented here, the western blots from this study, using anti-AIF antibody (Abcam ab32516) are reproduced in In collaboration with Ritchie et al . Notably, echocardiographic data suggest that dexrazoxane provides long-term cardioprotection, implying that prevention of cardiomyocyte damage during therapy can reduce the incidence of delayed doxorubicin-associated cardiomyopathy in long-term survivors without compromising the chances of oncological cure [The initial application in 2014 of CEME to dexrazoxane revealed an unequivocal signal defining a previously-unknown relationship between dexrazoxane and PAR polymer. Subsequently, the unique property of dexrazoxane to sequester PAR by base pairing was demonstrated using cal cure , 118.What does the proposed association between dexrazoxane and PAR mean to Oncologists?In addressing this important question some historical perspective must be introduced. Dexrazoxane reduces the incidence of anthracycline-induced heart failure by 80% and it is the only drug approved for its prevention . DespiteWhile beyond the scope of this review, the clinical consensus is that dexrazoxane does not compromise anti-tumour therapy. Indeed, in May 2017, the EMA Committee for Medicinal Products for Human Use approved the expansion of the Cardioxane Marketing Authorisation enabling increased use of dexrazoxane within the paediatric population for whom dexrazoxane had been previously contraindicated (dexrazoxane is marketed by Clinigen UK as a branded generic). A review of the evidence that historically led to a reassessment of the European Label for dexrazoxane found that dexrazoxane is not associated with an increased risk of second primary malignancies and that dexrazoxane therapy does not impair anthracycline’s anti-tumour efficacy .Thus, if the above changes and revisions lead to an increase in the use of dexrazoxane throughout different patient populations, then the alert clinician should be responsive to novel/atypical/unexpected clinical benefits and outcomes if dexrazoxane is acting in some part by sequestering PAR by base-pairing. et al propose that impaired cardiac function in doxorubicin-treated childhood cancer survivors is partly mediated by disruption of mitochondrial energy production and that this damage is abrogated by dexrazoxane [Indeed, scrutiny of existing clinical outcomes supports an interaction between dexrazoxane and PAR. For example, Lipshultzrazoxane . In a loAt a median follow-up of 7.8 years after treatment, doxorubicin-treated survivors without dexrazoxane had increased PBMC mtDNA copies per cell and concomitant use of dexrazoxane was associated with lower mtDNA copies per cell. The investigators add that mtDNA copies per cell in those who received dexrazoxane were within the normal ranges observed in their previous studies. OXPHOS activity was not different between groups. The investigators propose that in patients treated with doxorubicin alone, impaired mitochondria may undergo clonal expansion of mtDNA that functionally compensates for mutations or deletions that results in normal OXYPHOS and ATP production within the myocardium. They add that their findings support the evidence that dexrazoxane adjuvant therapy in paediatric high-risk ALL patients offers systemic mitochondrial protection and suggest a possible role of dexrazoxane prior to anthracycline therapy as a general protectant of mitochondrial function in other healthy tissues that include the ovaries . et al [Previously, Lebrecht et al  had prop et al .Notwithstanding alternative explanations, can the above effects upon mtDNA be reconciled with an interaction between dexrazoxane and PAR, and in the absence of dexrazoxane can PAR explain the delayed onset of anthracycline-associated cardiomyopathy? et al [ et al speculate that by contrast with the well-established positive regulatory role of PARP1 in maintaining nuclear DNA integrity, the addition of PAR groups on mtDNA repair enzymes may uniquely reduce their affinity to bind with DNA and thus may attenuate the rate of mtDNA repair.Using wild-type and PARP1-depleted A549 cells, Szczesny et al  investig et al [ et al [Accepting the new hypothesis that dexrazoxane sequesters PAR by base pairing, then arguably this sequestration state is comparable/equivalent to the PARP1-depleted cells used by Szczesny et al  and that et al . For exa et al . Accordi [ et al  may be a [ et al .A further example serves to illustrate how the existing data can be re-evaluated in the light of an interaction between dexrazoxane and PAR. While the acute cardiotoxic effects of doxorubicin are consistent with a doxorubicin-induced DNA damage response resulting in both PARP1-dependent apoptotic and necrotic cell death , 126, deTwo isoforms of MHC are expressed in the mammalian heart, α-MHC and β-MHC. The α-MHC isoform has a higher ATPase activity than β-MHC, and the contractile velocity of the heart is correlated with the relative amount of each isoform; hearts expressing greater amounts of α-MHC having a more rapid contractile velocity –138.The α- and β-MHC ratio correlates directly with the overall cardiac performance in both animals and in patients with cardiomyopathy and heart failure –145. PatDe Beer’s Group in the Department of Medical Physiology at Utrecht University observed that long-term administration of doxorubicin resulted in an impairment of the actin-myosin interaction in the hearts of male Wistar rats . Notably et al investigated whether the cardio-protective properties of dexrazoxane involve the prevention of the deleterious effects of doxorubicin upon the actin–myosin contractile machinery [Following their earlier observations of the effects of chronic treatment with doxorubicin upon the contractile function of the heart, de Beerachinery . They ob et al do not support a role for free radicals in mediating the deleterious effects of doxorubicin upon the actin–mysoin contractile machinery [Interestingly, there are no reports within the literature of an association between Top2β and MHC isoforms, and additional studies by de Beerachinery . Howeverachinery . MoreoveAre doxorubicin-induced alterations at the epigenome as manifest by a shift in the ratio between MHC isoforms and the effects of dexrazoxane in abrogating this shift, consistent with an interaction between dexrazoxane and PAR? et al in the Division of Cardiovascular Medicine at Stanford University School of Medicine show that Brahma-related gene 1 (Brg1), a chromatin-remodelling ATPase protein subunit of the BRG-1-Associated Factor (BAF complex), interacts with two other classes of chromatin-modifying enzymes, histone deacetylase (HDAC) and PARP, to regulate gene expression during cardiac growth, differentiation and hypertrophy [ et al show that in hypertrophic hearts PARP1 is bound to the proximal promoters of α-MHC and β-MHC, and that inhibition of PARP1 activity by the phenanthridinone-based PARP inhibitor PJ34 reduced both Brg1-mediated α-MHC repression and β-MHC activation in reporter assays, indicating that Brg1 and PARP1 cooperate to regulate MHC expression [Hangertrophy . In adulertrophy –155. In pression .Mahesh Gupta’s Group in the Department of Cardiothoracic Surgery at The University of Chicago demonstrate that nuclear extracts treated with anti-ADP-ribose antibodies reveal increased poly-ADP-ribosylation (PARylation) of nuclear proteins in failing hearts by comparison with controls, thus confirming the presence of PAR polymer [−/− mice was also evident from the analysis of hypertrophic marker genes. In PARP+/+ aortic artery-banded mice, the levels of β-MHC mRNA were highly elevated, whereas α-MHC levels were repressed, as expected. By contrast, in PARP−/− aortic artery-banded mice, no repression of α-MHC levels was observed, and the levels of β-MHC were increased to a much lesser extent.Notably,  polymer . From thIn their concluding remarks, they propose that PARP inhibitors may be useful agents for managing cardiomyopathies and heart failure.Taken together, these and other data are provocative and indicate that in some part, the cardiotoxic effects of doxorubicin and the cardioprotective effects of dexrazoxane, converge upon the epigenome. By comparison with acute damage, delayed-onset toxicity is consistent with a phenotypic switch that results from doxorubicin alteration(s) at the epigenome. Sequestration of PAR through both canonical Watson–Crick base pairing, and non-canonical Hoogsteen base-pairing provides a mechanism for the cardioprotective effects of dexrazoxane against the toxic effects of doxorubicin in the acute term, and abrogation of delayed-onset cardiomyopathy. et al have previously suggested a possible role of dexrazoxane prior to anthracycline therapy as a general protectant of mitochondrial function in healthy tissues in addition to the heart [ et al [very important neuroprotective properties’.Given the focal role of PAR in an overwhelming number of diseases, it is indeed thought provoking that dexrazoxane offers, for the first time, a unique opportunity to investigate the impact of sequestration of PAR, by comparison with inhibition of PARP, within a remarkably broad context. By way of example, and whilst beyond the scope of this review, the interaction between dexrazoxane and PAR offers the prospect that dexrazoxane can function as a cytoprotectant within other physiological systems (Lipshultzhe heart ). Neurophe heart . In that [ et al  concludepreviously unknown relationships’ within the published literature for a nominated drug within an elected therapeutic category. By comparison with the kind of data stored in structured databases, natural language text within the published literature is unstructured, amorphous and difficult to mine using the traditional algorithms. In practise, the greatest obstacle is missing data within a dataset that is small (thousands of data pieces) by comparison with the much larger size (millions of data pieces) of dataset sets mined using methods traditionally applied in commercial operations such as mining high street supermarket transactions. CEME overcomes the problem of missing data by adapting the use of a statistical method known as ‘antecedent surrogate variables’. Specifically, in exploring the mechanism of action of dexrazoxane as a cardioprotectant, the task was to characterise as exhaustively as possible cell signalling within all known molecular phenotypes (as determined by extracellular first messengers) of anthracycline-exposed cardiomyocytes. In practise, this is an extremely demanding operation that requires the manual input for all known molecular phenotypes of all known second messengers, enzymes, receptors, transcription factors and so on. To reduce the possibility of a type I error , in addition to dexrazoxane, the CEME process should be repeated for all known cardioprotectants of anthracycline-exposed cardiomyoctes; the list includes beta blockers, angiotensin inhibitors, angiotensin-converting enzyme inhibitors and statins. That is, previously unknown relationships between each cardioprotectant and cell signalling within the anthracycline-compromised cardiomyocyte should be explored. For practical reasons, this was not undertaken.The CEME algorithm is a well-validated methodology that has been successfully applied by McCormack Pharma to many drugs throughout more than three decades –134, 187In silico modelling studies demonstrate that dexrazoxane catalyses the formation of a hybrid self-assembled supramolecular structure between adjacent strands of PAR. These assemblies depict an antiparallel orientation of canonical Watson–Crick base pairing of dexrazoxane with adenine bases. In addition, these in silico studies show that dexrazoxane can also base pair with PAR strands by non-canonical Hoogsteen base pairing. Importantly, these supramolecular structures employing either canonical or non-canonical base pairing and combinations of the two, accord with the theoretical expectation of low-energy thermodynamically stable entities. Moreover, that such supramolecular assemblies are possible is strongly suggested by the work of other groups using molecules that are closely analogous to both dexrazoxane and PAR [in vivo conditions is lacking. Initially, aqueous stability could be explored by utilising in vitro methods such as thermal denaturation using circular dichroism and ultraviolet–visible spectroscopy [ and PAR , 104–107troscopy . These cin vitro study show that consistent with expectation, dexrazoxane prevents PAR-induced AIF release from isolated mitochondria. However, dose-ranging studies are needed, and equilibrium times require investigation. The utilisation of exogenous PAR as used by the author is not a paradigm of a deep compartment for the accumulation of dexrazoxane and consequently does not adequately represent the in vivo situation. Preferably, further studies should incorporate the use of whole cells, such as isolated neonatal rat cardiomyocytes together with the use of ionising radiation to induce DNA damage with subsequent elaboration of endogenous PAR.The results of a preliminary The conformational relationship of the non-covalent interaction between dexrazoxane and PAR was explored using a modified version of Allinger’s Molecular Mechanics MM2 force field (for review see ). Accord