Question:
You will be presented with the full text of a biomedical research paper. Please write an abstract for this paper. Your response should include the abstract and no additional text.

Paper text:
most osteoporotic compression fractures heal with mild residual deformities , and clinical complications are usually rare5 ) .
when conservative treatment offers no symptomatic improvement , percutaneous vertebroplasty or balloon kyphoplasty have been safely used and have provided rapid pain relief with mechanical stabilization10 ) . sometimes , however , patients complain about both back pain and newly developed leg pain following vertebral compression fractures
. the main symptom can be radicular leg pain , rather than axial pain , which mimics foraminal stenosis or disc herniation .
this radiculopathy is thought to be caused by the encroachment of the intervertebral foramen2 ) . in those cases ,
it is difficult to perform bone cement augmentation because it is known that percutaneous vertebroplasty is a relative contraindication to the conditions causing radicular symptoms in patients who present with canal encroachment1 ) .
this study aimed to investigate the risk for newly developed radiculopathic leg pain following lumbar osteoporotic compression fracture by analyzing the fracture pattern .
we also studied whether bone cement augmentation would lead to a good or poor clinical outcome .
between may 2008 and april 2010 , 238 patients underwent single - level vertebroplasty or balloon kyphoplasty for osteoporotic compression fractures in our institute .
the inclusion criteria were as follows : 1 ) fracture location under l2 level that can lead to radiculopathic leg pain following vertebral compression fracture ; 2 ) osteoporotic spine ( t - score by bone mineral densitometry lower than -3.0 ) ; 3 ) follow - up period longer than 6 months ; and 4 ) no radiculopathic leg pain before the osteoporotic compression fracture .
patients with obvious burst fractures at the time of injury , with previous history of spine surgery or radiculopathic symptom before compression fracture , were excluded in this study . of these 238 patients , 59 who had osteoporotic compression fractures and underwent percutaneous vertebroplasty or balloon kyphoplasty under the l2 level
were enrolled in this study . to study whether the fracture pattern influences the newly developed radiculopathy and back pain ,
the 59 patients were divided into two groups , namely group a ( n=44 ) , back pain - only , and group b ( n=15 ) , back pain with newly developed unilateral leg pain .
fractures were evaluated using early magnetic resonance imaging ( mri ) based on kanchiku 's method and we classified into three types according to the main position of the fracture line on the basis of t1 , t2-weighted fat and suppression images ( superior , middle , and inferior ) ( fig .
the preoperative group differences data were evaluated by the unpaired student t - test using the spss program ( spss inc . , chicago , il , usa ) , and intragroup changes associated with the procedure were evaluated using the student t - test for paired data with a p<0.01 considered the significance level .
the anatomical distribution of the 59 patients was as follows : l2 ( n=19 ) , l3 ( n=18 ) , l4 ( n=14 ) , and l5 ( n=8 ) . among them
there were no significant differences between group a and group b with respect to age and gender .
the overall incidence of radiculopathic leg pain under the l2 level was 25% ( n=15 ) .
there was no newly developed radiculopathy at the l2 level , and the frequency of radiculopathic leg pain increased with descending levels ( table 1 ) .
although vertebral collapse was not severe in lumbar radiographs and mri , 10 of 15 patients in the group b showed compression fracture and suspicious impingement of the corresponding nerve root at the intervertebral foramen . in the analysis of fracture pattern under the l2 level , which showed radiculopathy , only the back pain group ( group a ) demonstrated symptoms relating to the superior fracture type .
however , the fracture pattern in the group with back and radiculopathic pains ( group b ) was mostly related to the inferior fracture type ( table 2 ) .
such a difference was statistically significant ( p<0.01 ) and can be attributed to the different pathophysiological mechanism in the two groups ( fig .
the mean back pain score of both groups showed significant improvement at the last follow - up .
interestingly , the mean pain score of leg pain in group b also showed significant improvement after bone cement augmentation without decompressive open surgery .
the visual analogue scale decreased from a preoperative score of 6.5 to 3.0 at 7 postoperative days and it was maintained at final follow - up with respect to radiculopathy ( fig .
3 ) . three patients ( 2 in l4 and 1 in l5 ) in group b had recurrent radicular pain during the follow - up period , but their pain was tolerable , as controlled by analgesics ( fig . 4 , 5 ) .
in the analysis of fracture pattern under the l2 level , which showed radiculopathy , only the back pain group ( group a ) demonstrated symptoms relating to the superior fracture type .
however , the fracture pattern in the group with back and radiculopathic pains ( group b ) was mostly related to the inferior fracture type ( table 2 ) .
such a difference was statistically significant ( p<0.01 ) and can be attributed to the different pathophysiological mechanism in the two groups ( fig .
the mean back pain score of both groups showed significant improvement at the last follow - up .
interestingly , the mean pain score of leg pain in group b also showed significant improvement after bone cement augmentation without decompressive open surgery .
the visual analogue scale decreased from a preoperative score of 6.5 to 3.0 at 7 postoperative days and it was maintained at final follow - up with respect to radiculopathy ( fig .
3 ) . three patients ( 2 in l4 and 1 in l5 ) in group b had recurrent radicular pain during the follow - up period , but their pain was tolerable , as controlled by analgesics ( fig . 4 , 5 ) .
compression fractures caused by osteoporosis are common in the elderly and are often encountered by spine surgeons .
it is well known that bone cement augmentation procedures such as percutaneous vertebroplasty or balloon kyphoplasty improve back pain from osteoporotic compression fractures4,8 ) . however , in some instances , lumbar osteoporotic compression fractures without evident canal compromise cause radiculopathic radiating pain and spinal canal stenosis leading to claudication7 ) .
conservative treatment using a lumbar brace for compression fracture forces the posture in lumbar extension , worsening central or foraminal stenosis2 ) .
surgical treatment of lumbar stenosis with open decompression with instrumented stabilization has the potential for significant complications because of comorbidities related to advancing age , especially severe osteoporosis and high risk for instrumentation failure9 ) .
this study was performed to clarify and analyze whether an early fracture pattern based on mri classification influences the newly developed radiculopathy in osteoporotic compression fractures and clinical outcome after bone cement augmentation procedure . in this study , the incidences of acute and newly developed leg pain after
the possible cause of radiculopathic leg pain after osteoporotic compression fracture may be considered to be the following mechanism : when the osteoporotic vertebral fracture occurs , if the bony fragments from the collapsed body invade the foraminal space , the root can be compressed directly , leading to radiculopathy .
the decreased foraminal height by vertebral body collapse will be worse . by categorizing fractures on the basis of fracture line
the second plausible mechanism may be considered to be a referred pain , which is distributed far from the site of injury .
doo et al.3 ) reported that the posterior branches can be irritated by the narrowing of the intervertebral foramen resulting from the decreased height of the vertebral bodies , their pain may have been distributed in these areas as a radicular or somatic referred pain .
we performed bone cement augmentation alone because it is a simple and less invasive procedure , and it was efficacious in providing satisfactory pain relief , not requiring open decompressive surgery even in radiculopathy .
the pain relief mechanisms by vertebral augmentation procedures may be deduced as the following mechanism .
first , segmental stability provided by the cement augmentation is increased , and second , retropulsion and foraminal narrowing are decreased . as spondylotic changes progress in the lumbar spine during aging , the foraminal space decreases with facet hypertrophy , reduced disc height , and foraminal or extraforaminal disc herniations .
actually , the radicular pain in most patients in group b was aggravated in the erect position .
because the posterior wall of the vertebral body inferior to the pedicle constitutes a large portion of intervertebral foramen , the size of the intervertebral foramen will diminish when the compression fracture involves that part of the vertebra .
if the root impingement occurs by a combination of spondylotic foraminal stenosis and vertebral fracture , the degree of root compression will increase by weight loading because of the decreased stiffness of the vertebral body . if this is the main mechanism of the patients ' symptoms , bone cement augmentation may play a major role in relieving the radicular pain secondary to some degree of fracture reduction and mechanical stabilization .
we could achieve favorable clinical outcome by bone cement augmentation procedure alone . despite our successful results ,
the authors ' proposed pathomechanism is presumptive and is supported mainly by the patient 's immediate and symptomatic improvement during follow - up . for a more scientific approach to this subject , experimental data include accurate measurement of the size of the intervertebral foramen according to the weight loading in a fractured vertebra .
experimental study with the finite element model can be a good method that can confirm our results . in the near future ,
randomized clinical trials for comparative studies in a larger population for a longer period are necessary .
by categorizing fractures on the basis of fracture line , we found that inferior - type fractures were more related to the development of radiculopathic leg pain .
bone cement augmentation alone can be a safe and efficient option in patients with painful osteoporotic compression fracture and radiculopathy .

Answer:
objectivethe purpose of this study was to analyze the relationship between fracture pattern and the development of acute radiculopathy after osteoporotic lumbar compression fracture.methodsthis study included 59 patients who underwent bone cement augmentation for osteoporotic compression fracture below the l2 level , which can lead to radiculopathic radiating pain .
 the patients were divided into two groups according to the presence of radiculopathy ( group a : back pain only ; group b : back pain with newly developed radiating pain ) .
 we categorized compression fractures into three types by the position of the fracture line .
 the incidence of newly developed radiculopathy was examined retrospectively for each compression fracture type.resultsthe overall incidence of newly developed leg pain ( group b ) was 25% , and the frequency increased with descending spinal levels ( l2 : 0% , l3 : 22% , l4 : 43% , and l5 : 63% ) .
 the back pain - only group ( group a ) had mostly superior - type fractures . on the other hand , the back pain with radiculopathy group ( group b ) had mostly inferior - type fractures .
 most patients in group b showed significant relief of leg pain as well as back pain after bone cement augmentation.conclusionthe incidence of a newly developed , radiating pain after osteoporotic compression fractures increased gradually from the l3 to l5 levels .
 most of these fractures were of the inferior type , and the bone cement augmentation procedures seemed to be sufficient for relief of both back and radiating pain .


Question:
You will be presented with the full text of a biomedical research paper. Please write an abstract for this paper. Your response should include the abstract and no additional text.

Paper text:
fear of hypoglycaemia and gain in body weight act as barriers for initiation of insulin therapy .
modern insulin analogues are a convenient new approach or tool to glycaemic control , associated with low number of hypos and favourable weight change .
a1chieve , a multinational , 24-week , non - interventional study , assessed the safety and effectiveness of insulin analogues in people with t2 dm ( n = 66,726 ) in routine clinical care .
please refer to editorial titled : the a1chieve study : mapping the ibn battuta trail .
the patient characteristics for the entire cohort divided as insulin - nave and insulin users is shown in the table 1 .
the majority of patients ( 71.28% ) started on or switched to biphasic insulin aspart .
other groups were insulin detemir ( n = 28 ) , insulin aspart ( n = 24 ) , basal insulin plus insulin aspart ( n = 13 ) and other insulin combinations ( n = 3 ) . overall demographic data after 24 weeks of treatment , overall hypoglycaemic events reduced from 2.1 events / patient - year to 0.0 events / patient - year in insulin nave group and from 6.8 events / patient - year to 0.0 events / patient - year in insulin users group .
the hypoglycaemia incidence in insulin naive group at 24 weeks was lower than that observed in insulin users at baseline .
major hypoglycaemic events decreased from 0.5 events / patient - year to 0.0 events / patient - year in insulin nave group while no change from baseline ( 1.3 events / patients - year ) was observed for insulin user group .
mean hba1c and fpg values improved from baseline to study end in the insulin nave group [ table 4 ] .
overall efficacy data of the total cohort , 340 patients started on biphasic insulin aspart  ogld , of which 153 ( 45% ) were insulin nave and 187 ( 55% ) were insulin users .
after 24 weeks of starting or switching to biphasic insulin aspart , hypoglycaemic events reduced from 2.3 events / patient - year to 0.0 events / patient - year in insulin nave group and from 6.3 events / patient - year to 0.0 events / patient - year in insulin users .
quality of life improved at the end of the study [ table 5 and 6 ] .
biphasic insulin aspartoral glucose - lowering drug safety data mean hba1c and fpg values improved from baseline to study end in those who started on or were switched to biphasic insulin aspart for insulin nave group [ table 7 ] .
biphasic insulin aspartoral glucose - lowering drug efficacy data of the total cohort , 7 patients started on basal + insulin aspart  ogld , of which 2 ( 28.6% ) were insulin nave and 5 ( 71.4% ) were insulin users .
after 24 weeks of treatment , hypoglycaemic events reduced from 10.4 events / patient - year to 0.0 events / patient - year in insulin users whereas hypoglycaemia remained nil in insulin naive group , similar to baseline .
quality of life improved after 24 weeks of treatment [ table 8 and 9 ] .
basal+insulin aspartoral glucose - lowering drug safety data mean hba1c and fpg values improved from baseline to study end in those who started on or were switched to basal + insulin aspart  oglds for insulin nave group . of the total cohort ,
90 patients started on insulin detemir  ogld , of which 57 ( 63.3% ) were insulin nave and 33 ( 36.7% ) were insulin users .
after 24 weeks of starting or switching to insulin detemir , hypoglycaemic events reduced from 2.5 events / patient - year to 0.0 events / patient - year in insulin nave and from 6.3 events / patient - year to 0.0 events / patient - year in insulin user groups [ table 10 and 11 ] .
insulin detemiroral glucose - lowering drug safety data mean hba1c and fpg values improved from baseline to study end in those who started on or were switched to insulin detemir  oglds for insulin - nave group [ table 12 ] .
insulin detemiroral glucose - lowering drug efficacy data of the total cohort , 37 patients started on insulin aspart  ogld , of which 26 ( 70.3% ) were insulin nave and 11 ( 29.7% ) were insulin users .
after 24 weeks of treatment , hypoglycaemic events reduced from 14.2 events / patient - year to 0.0 events / patient - year in insulin users whereas , hypoglycaemic events remained nil in insulin users , similar to baseline .
quality of life improved at the end of the study [ table 13 and 14 ] . insulin aspartoral glucose - lowering drug safety data mean hba1c and fpg values improved from baseline to study end in those who started on or were switched to insulin aspart  oglds for insulin nave group [ table 15 ] .
of the total cohort , 340 patients started on biphasic insulin aspart  ogld , of which 153 ( 45% ) were insulin nave and 187 ( 55% ) were insulin users .
after 24 weeks of starting or switching to biphasic insulin aspart , hypoglycaemic events reduced from 2.3 events / patient - year to 0.0 events / patient - year in insulin nave group and from 6.3 events / patient - year to 0.0 events / patient - year in insulin users .
quality of life improved at the end of the study [ table 5 and 6 ] .
biphasic insulin aspartoral glucose - lowering drug safety data mean hba1c and fpg values improved from baseline to study end in those who started on or were switched to biphasic insulin aspart for insulin nave group [ table 7 ] .
of the total cohort , 7 patients started on basal + insulin aspart  ogld , of which 2 ( 28.6% ) were insulin nave and 5 ( 71.4% ) were insulin users .
after 24 weeks of treatment , hypoglycaemic events reduced from 10.4 events / patient - year to 0.0 events / patient - year in insulin users whereas hypoglycaemia remained nil in insulin naive group , similar to baseline .
quality of life improved after 24 weeks of treatment [ table 8 and 9 ] .
basal+insulin aspartoral glucose - lowering drug safety data mean hba1c and fpg values improved from baseline to study end in those who started on or were switched to basal + insulin aspart  oglds for insulin nave group .
of the total cohort , 90 patients started on insulin detemir  ogld , of which 57 ( 63.3% ) were insulin nave and 33 ( 36.7% ) were insulin users .
after 24 weeks of starting or switching to insulin detemir , hypoglycaemic events reduced from 2.5 events / patient - year to 0.0 events / patient - year in insulin nave and from 6.3 events / patient - year to 0.0 events / patient - year in insulin user groups [ table 10 and 11 ] .
insulin detemiroral glucose - lowering drug safety data mean hba1c and fpg values improved from baseline to study end in those who started on or were switched to insulin detemir  oglds for insulin - nave group [ table 12 ] .
of the total cohort , 37 patients started on insulin aspart  ogld , of which 26 ( 70.3% ) were insulin nave and 11 ( 29.7% ) were insulin users .
after 24 weeks of treatment , hypoglycaemic events reduced from 14.2 events / patient - year to 0.0 events / patient - year in insulin users whereas , hypoglycaemic events remained nil in insulin users , similar to baseline .
quality of life improved at the end of the study [ table 13 and 14 ] .
insulin aspartoral glucose - lowering drug safety data mean hba1c and fpg values improved from baseline to study end in those who started on or were switched to insulin aspart  oglds for insulin nave group [ table 15 ] .
our study reports improved glycaemic control ( hba1c , fpg ) following 24 weeks of treatment with any of the insulin analogues ( biphasic insulin aspart ; basal + insulin aspart ; insulin detemir ; insulin aspart ) with or without ogld .
major hypoglycaemic events decreased from 0.5 events / patient - year to 0.0 events / patient - year in insulin nave group while no change from baseline ( 1.3 events / patients - year ) was observed for insulin user group .
overall , body weight reduced in insulin nave group whereas no change in body weight was observed for insulin users .
though the findings are limited by number of patients , still the trend indicates that insulin analogues can be considered effective and possess a safe profile for treating type 2 diabetes in rajasthan , india .

Answer:
background : the a1chieve , a multicentric ( 28 countries ) , 24-week , non - interventional study evaluated the safety and effectiveness of insulin detemir , biphasic insulin aspart and insulin aspart in people with t2 dm ( n = 66,726 ) in routine clinical care across four continents.materials and methods : data was collected at baseline , at 12 weeks and at 24 weeks . this short communication presents the results for patients enrolled from rajasthan , india.results:a total of 477 patients were enrolled in the study .
 four different insulin analogue regimens were used in the study .
 patients had started on or were switched to biphasic insulin aspart ( n = 340 ) , insulin detemir ( n = 90 ) , insulin aspart ( n = 37 ) , basal insulin plus insulin aspart ( n = 7 ) and other insulin combinations ( n = 2 ) . at baseline
 glycaemic control was poor for both insulin nave ( mean hba1c : 8.3% ) and insulin user ( mean hba1c : 8.4% ) groups .
 after 24 weeks of treatment , both the groups showed improvement in hba1c ( insulin nave : 0.9% , insulin users : 1.2% ) .
 major hypoglycaemic events decreased from 0.5 events / patient - year to 0.0 events / patient - year in insulin nave group while no change from baseline ( 1.3 events / patients - year ) was observed for insulin users .
 sadrs were not reported in any of the study patients.conclusion:starting or switching to insulin analogues was associated with improvement in glycaemic control with a low rate of hypoglycaemia .


Question:
You will be presented with the full text of a biomedical research paper. Please write an abstract for this paper. Your response should include the abstract and no additional text.

Paper text:
rituximab is a relatively novel medication for immunomodulation in current clinical practice . with its use becoming fairly widespread and newer indications being approved at a fast rate it is also imperative to watch for any adverse reactions , which may need monitoring parameters during therapy
a 54-year - old man was diagnosed with limited form of wegener 's granulomatosis 1 year before the current hospitalization .
he had failed therapy with corticosteroids and was recommended rituximab for resistant disease state . besides lung and upper airway involvement , he had no other organ involvement from wegener 's disease .
five days after receiving the infusion he developed postural dizziness and had near syncopal episodes , which led to hospital admission .
he denied chest pain , shortness of breath , fever , palpitations , and any rash .
vital signs on admission revealed hypotension with a blood pressure of 80/40 mmhg , pulse 75 beats / min , respiratory rate 20/min , and temperature 98f .
electrocardiogram ( ecg ) showed a new onset left bundle branch block ( lbbb ) [ figure 1c ] as compared to his prior ecg performed a month back before the current admission [ figure 1a ] . in view of new lbbb
, an urgent transthoracic echocardiogram was performed revealing normal left ventricular systolic function and absence of wall motion abnormalities .
patient was admitted to intensive care unit and was treated with intravenous fluids and inotropic agents for hypotension .
contrast - enhanced cardiac magnetic resonance imaging was conducted to rule out focal myocarditis as a cause of the new onset lbbb ; and failed to show any abnormality . on day 2 of admission ,
telemetry showed intermittent lbbb [ figure 1b ] and eventually the lbbb was replaced by a narrow qrs complex [ figure 1d ] with only supportive treatment .
patient remained hemodynamically stable off inotropic agents and was discharged home and is doing well on follow up .
telemetric strip new onset left bundle branch block ( lbbb ) intermittent sinus beats with lbbb and finally resolution of lbbb
rituximab , the first monoclonal antibody approved by the united states food and drug administration ( fda ) for the treatment of malignant disease , is being used to treat a wide variety of conditions in modern practice , including non - hodgkin 's lymphoma , wegener 's granulomatosis , rheumatoid arthritis , thrombotic thrombocytopenic purpura , among many others .
currently , four adverse effects that warrant a " black box " warning in the package insert are known : infusion reactions , tumor lysis syndrome , mucocutaneous reactions , and progressive multifocal leukoencephalopathy .
it is also known to promote severe orthostatic hypotension often associated with allergic symptoms , urticaria , bronchospasm , and angioedema .
most adverse events occur during or after the first infusion of rituximab , and the number and severity of adverse events decreases with subsequent infusions . as with any novel therapy , new adverse reactions are being noted with increasing time and usage . in a multicenter phase
ii study conducted to assess the toxicity and response rates to rituximab in b - cell malignancies that express cd20 , 10 out of 131 patients developed an arrhythmia with treatment . these included bradycardia ( n = 3 ) , atrial fibrillation ( n = 2 ) , and nonspecified arrhythmia or tachyarrhythmia ( n = 5 ) .
one other patient had palpitations , and another was noted to have premature ventricular complexes . in most cases ,
ventricular tachycardia during the infusion of rituximab and prompt disappearance after discontinuation of infusion was first reported in 2005 .
complete atrioventricular block induced by rituximab monotherapy in an 83-year - old has also been described in literature .
another recent report of polymorphic ventricular tachycardia causing syncope during initial infusion of rituximab raises concerns of arrhythmogenic side effects of this medication . despite these reports a study to determine
the maximum tolerated infusion rate of rituximab with special emphasis on monitoring the effect of rituximab on cardiac function concluded with confirmation of lack of cardiotoxic effect of a fast infusion rate .
however , we could not come across any reported case of lbbb associated with rituximab infusion .
increased ventricular dysfunction after rituximab infusion has been seen which is attributed to growth of reticulin fiber in cardiac myocytes .
reticulin deposition may have an effect on conduction system causing rhythm abnormalities and interventricular conduction delays as seen in our patient .
it is also hypothesized that the drug affects conduction by inhibiting the calcium - ion channel properties of the cd20 antigen , which could lead to formation of early after depolarizations .
still the mechanism by which rituximab may cause arrhythmias is presently unclear and needs more research .
also , it would be prudent to keep patients on electrocardiac monitoring during drug infusions to monitor for possible conduction abnormalities , especially the initial infusions .

Answer:
rituximab ( a monoclonal antibody directed against cd 20 ) therapy can be acutely complicated by infusion reactions and cardiac arrhythmia on rare occasions .
 we report the first case of a new onset left bundle branch block ( lbbb ) after rituximab therapy for wegener 's vasculitis .


Question:
You will be presented with the full text of a biomedical research paper. Please write an abstract for this paper. Your response should include the abstract and no additional text.

Paper text:
this special issue of fungal genetics and biology describes a comprehensive effort to develop methods and expertise to tackle one of the world s most serious fungal diseases of wheat .
the series of papers within this issue are designed to provide a resource for a new generation of plant pathologists who we hope will be inspired to investigate the biology of septoria blotch of wheat and develop new and durable disease control strategies .
wheat is the world s most widely cultivated crop and is responsible for providing about a quarter of the calories to humankind .
global wheat production was more than 700  million tons in 2013 , with the european union and china producing the largest harvests , and wheat being cultivated across most of the temperate regions of the planet ( gurr and fones , 2015 ; rudd et al . , 2015 ) .
as well as being the most widely grown crop , wheat is also the most traded food on the international markets  indeed more wheat is traded than all other crops combined . along with rice and maize ,
there are many threats to wheat productivity , including the availability of high quality land for cultivation , which is threatened by urbanisation , the sustainable use of fertilisers , which are used in enormous quantities , especially in europe , and the prevalence of diseases .
wheat diseases , such as septoria blotch , provide an ever - present threat to wheat production and if they could be controlled effectively , would provide a much - needed boost to productivity that will be required to satisfy increasing global demand for food in the next two decades ( courbot et al . , 2015 ;
what then are the essential pre - requisites to allow us rapidly to understand the biology of zymoseptoria tritici ? what requirements are necessary to allow a fungal pathogen to be regarded as a model system ( perez - nadales et al . , 2014 ) and for new insights into the underlying mechanisms of infection and virulence to be understood ?
the last 20  years have seen pathogens , such as the corn smut fungus ustilago maydis and the rice blast fungus magnaporthe oryzae , for example , emerge as model systems ( dean et al . , 2012 ) .
in both cases , this required the development of many tools , which took many years .
it is by considering these issues that this collection of reviews and primary publications has been put together .
arguably , the first pre - requisite to being able to investigate any disease is a comprehensive description of the life cycle of the organism and the spatial and temporal dynamics of the infection process . for z. tritici
this means a cell biological investigation of what happens from the moment a spore germinates on the leaf surface , to its location of a stoma and invasion of underlying leaf tissue .
using live cell imaging approaches , facilitated by the tools generated and described elsewhere in this special issue , the cell biology of infection is addressed , with an emphasis on the developmental biology of the fungus , its dimorphic growth habit , its ability to perceive and respond to the leaf surface , and its ability to undertake developmental transitions during its establishment of a wheat infection ( steinberg , 2015 ) . without a  road - map of how an infection proceeds , it is difficult to identify points of disease intervention or to understand how any single gene product , or family of proteins ( from the pathogen or its host ) , might be important in disease .
the next essential pre - requisite for the model pathogen tool - kit is the ability to test the function of any gene . without an ability to construct mutants ,
it is hard to carry out any reverse genetic approach to test the importance of any selected biological process .
therefore , a high frequency transformation system is essential , with a ready supply of selectable marker genes to allow multiple constructs to be expressed , and the ability to carry out targeted mutations ( kilaru and steinberg , in 2015 ; kilaru et al . , 2015a ; schuster et al . ,
the latter can be dramatically improved by development of a strain of z. tritici in which the non - homologous dna end - joining pathway is impaired ( sidhu et al .
coupled to this , it would be advantageous to have a means by which the function of a gene could be attenuated but without complete loss of function , such as virus - induced gene silencing , and the ability to regulate genes driven by a set of highly controllable promoters by which gene expression can be predictably controlled ( kilaru et al .
the latter will also provide the means to over - express , or mis - time the expression of a given gene to tests its function , or requirement ( cairns et al . , 2015 ) .
next , a means by which gene products can be localised using expression of fluorescently - labelled fusion proteins is essential , preferably with optimised fluorescent markers , calibrated and tested for the pathogen and in amenable vectors , with easy cloning strategies for ready construction ( kilaru et al .
, 2015c ; mehrabi et al . , 2015 ; schuster et al . , 2015a ; sidhu et al .
this provides the means to carry out live cell imaging of a pathogen undergoing infection and directly observing the position , fate and turnover of a gene product , which is absolutely pivotal to understanding its function . but this will make no sense without some context , so having the ability to unequivocally identify organelles , such as nuclei , er , golgi bodies , peroxisomes , and mitochondria is essential ( schuster et al . , 2015b ; kilaru et al . , 2015b ; guo et al .
, 2015a , b ) . also , to understand intracellular trafficking it is necessary to be able to identify and track the movement of endosomes , secretory vesicles and the associated components of the actin and microtubule cytoskeleton and their corresponding motor proteins , so that the transport of proteins and the regulation of such processes can be studied ( guo et al . , 2015a , b ; kilaru et al . , 2015c ; schuster et al .
when considered together , these tools will therefore allow rapid elucidation of gene function in z. tritici , as rapidly as in any fungal pathogen studied today .
so far , of course , we have only considered addressing the functions of individual genes as opposed to gene families and the function of the whole genome and the corresponding , context - dependent proteomes that are expressed during pathogenesis . to address these
requires first of all a detailed understanding of the genome ( goodwin et al . , 2011 ; testa et al . , 2015 ) and its inherent , strain - to - strain variation , and how this correlated with pathotype .
understanding the role , for example , of accessory , or supernumerary chromosomes , as opposed to the core , invariant gene repertoire of the genome will be key ( mcdonald et al . , 2015 ) . an ability to analyse global patterns of gene expression , proteomic and metabolomics data sets during infection , will also be necessary so that the total expressed proteome can be defined and sub - sets associated with the effector repertoire of the pathogen , proteins required for symptom development and those necessary for fungal proliferation can be readily classified , define and then functionally analysed ( ben mbarek et al .
methods to define transcriptional networks by chromatin immuno - precipitation coupled to next generation sequencing to define targets genes downstream of transcription factors , will also allow networks of gene expression to be distinguished readily ( soyer et al . ,
protein interactions between fungal proteins , but also between fungal proteins that act upon host plant proteins , is also essential , with the ready availability of yeast two - hybrid libraries and associated bespoke protocols to z. tritici ( ma et al . , 2015 ) finally ,
of course we need to consider the plant host and within this context , transgenic wheat lines expressing organelle - specific markers are already available and being constructed to augment host - pathogen cell biological analysis , while detailed analysis of sources of resistance can guide plant breeding strategies such that durable combinations of resistance genes can be identified and introduced into elite , high yielding commercial wheat cultivars ( brown et al . , 2015 ) .
with wider knowledge of the fungal pathogen population and prevailing virulence specificities , should some the ability to breed for exclusion of the most prevalent , prevailing pathotypes of the fungus ( vallet et al . , 2015 ) , providing a direct route to disease control at least in the medium term .
the new methods and resources presented in this special issue mean that the z. tritici research community now has , arguably , the same level of research tools as any fungal model system .
this is remarkable , because it has happened in a very short period of time in response to an acute need , articulated by growers and the agricultural biotechnology industry .
an integrated programme has been funded and undertaken to carry out this method development and to begin to apply the newly acquired expertise to understanding this disease .
many research questions immediately present themselves . what is the purpose of the morphogenetic plasticity exhibited by z. tritici and how are these dimorphic transitions regulated
how is long - distance control of pathogenesis - associated gene expression achieved and how does the fungus perceive and respond to the internal plant tissue environment during infection ? how is sporulation triggered and correctly regulated ? all of these questions can now be addressed and the answers provided will result not only in many of the fungicide targets of the future , but also perhaps to some longer - term strategies for broad spectrum disease control .
so , to those of you reading this commentary who have never previously considered studying z. tritici , or perhaps not even considered studying a fungal pathogen before , think of the obstacles that have just been removed .

Answer:
septoria blotch of wheat is one of the world s most serious plant diseases , which is difficult to control due to the absence of durable host resistance and the increasing frequency of fungicide - resistance . the ascomycete fungus that causes the disease , zymoseptoria tritici , has been very challenging to study
 .
 this special issue of fungal genetics and biology showcases an integrated approach to method development and the innovation of new molecular tools to study the biology of z. tritici . when considered together
 , these new methods will have a rapid and dramatic effect on our ability to combat this significant disease .


Question:
You will be shown the title of a chemistry paper, together with sections excerpted from the body of the paper. The paper sections may include HTML tags like `<p>` and `</p>`; please ignore these. Your task is to write an abstract for the paper. Your response should include the abstract and no other text.

Title:
Is Lewis acidity in metal dications triggered by solvent shell fluctuations?

Paper sections:
Introduction

In aqueous solution Lewis acidity is promoted via the hydrolysis reaction (1):

and for metal dications the hydrolysis constant associated with Eq. 1, K h , is defined as (1)

which provides a measure of the acidic strength of water when M 2+ cations are present in aqueous solution. Numerous methods have been proposed in an attempt to correlate the physical properties of metal ions with the value of pK h (= -log K h ); for example plotting against various combination of charge to size ratio (2,3). For closed-shell cations, such as the alkaline earth metals, these correlations often work and suggest that pK h reflects both the underlying electrostatic nature of the M-O bond and the contribution changes in charge density make to the M 2+ -water interaction. However, there are some very notable exceptions to any of the methods that have been proposed, with the most obvious being Sn 2+ , Pb 2+ and Hg 2+ . Some underlying anomalies are obvious; for example, ionic radius of Pb 2+ is comparable to those of both Ca 2+ and Sr 2+ , in aqueous solution the former yields a proton concentration that is two orders of magnitude larger than either of the latter. Similarly, Mg + has a second ionisation energy that is comparable to Pb + , but this time there is almost four orders of magnitude difference in the proton concentrations they generate in aqueous solution. Suggestions as to why Sn 2+ , Pb 2+ and Hg 2+ behave differently, have included: (i) their "softness" (4); (ii) changes in coordination number, particularly in the case of Sn 2+ (5,6); and (iii) covalent contributions to the M-OH 2 bond (5). Some attempts to understand and/or quantify hydrolysis have actually omitted Sn 2+ , Pb 2+ and Hg 2+ from the discussion. At a molecular (gas phase) level, there have now been numerous experimental studies demonstrating the ability of alkaline earth metal dications to promote proton release from water molecules. Theoretical interpretation of these (7) and similar events proposed for Sn 2+ , 3 Pb 2+ and Hg 2+ (8) has involved salt bridge structures which have been shown to lower barriers to proton transfer (7,8).

The purpose here is to develop this gas phase analogy of metal ion acidity by interpreting recent experimental data in terms of how shells of solvent molecules might behave when metal cations are in aqueous solution. In a recent series of papers results were present showing how stable gas phase metal dication complexes were with respect to the proton transfer reaction (9,10):

Where X is OH (water), OCH 3 (methanol) or NH 2 (ammonia). In the case of water, Eq. 3 is equivalent to the forward reaction in the hydrolysis step, Eq. 1. For each of the three molecular systems, a value for n, identified as n s , was recorded that corresponded to the minimum number of solvent molecules required to stabilise a dication complex against spontaneous hydrolysis.

For water, measurements for a series of [M(H 2 O) n ] 2+ complexes were performed on the following metal dications: Sr 2+ , Ca 2+ , Mg 2+ , Mn 2+ , Cr 2+ , Cu 2+ , Zn 2+ , Pb 2+ or Sn 2+ , and these results are summarised in Table 1 giving a data set that spans a significant fraction of the available pK h measurements. The metal dications show considerable variation in the values determined for n s ; however, the results obtained for Sn 2+ and Pb 2+ are particularly interesting in that the latter needs at least 11 water molecules to stabilise the ion against gas phase hydrolysis and for Sn 2+ an incredible 26 water molecules are required. Both of these numbers are far in excess of the conventional picture of a stable solvated dication surrounded by just a primary shell of water molecules (5,11), and the results for Sn 2+ suggest that secondary and quite possibly tertiary shells of water are implicated in the ion solvation/stabilisation process (12).

Through the data in Table 1 a link has been proposed between pK h and the critical size at which hydrated gas phase dications undergo spontaneous charge separation (10) (13)(14)(15). Secondly, there is also a more limited link between n s and the Irving-Williams series, namely, Mg 2+ and Ca 2+ < Mn 2+ < Cu 2+ ≈ Zn 2+ (15,16).

The relationship between n s and pK h works because it reflects instability within each gas phase M 2+ /water unit; however, a more realistic view for the condensed phase might be to consider the numbers of water molecules involved as representing a critical set of solvation shells over which a metal cation has influence. Measurements of the binding energies of water molecules to Ca 2+ have shown that the charge on the metal ion exerts an influence on binding out as far as the third solvation shell (17); however, Table (1) would suggest that the conditions necessary for promoting reaction (3) and those responsible for binding molecules to some of the metal ions have different requirements. Exceptions would appear to be Pb 2+   and Sn 2+ , where promoting instability clearly involves water molecules in the second and third solvation shells. Within an aqueous environment fluctuations in solvent shell occupation 5 in close proximity to a metal ion could cause transient fluctuations in charge density on or in the vicinity of the metal ion, which in turn, might promote proton transfer. This view could be considered as being derived from the Marcus theory of electron transfer, where solvent fluctuation drives the movement of charge (18). A similar approach has been used to describe the mechanism of autoionisation by liquid water, where computer simulations have shown that fluctuations in the concerted motion of atoms can promote charge separation (19). For a metal cation to undergo hydrolysis solvent shell coordination would have to drop below n s , and in the case of Sn 2+ , that could happen very frequently because it would be hard to maintain an extended array of 25 water molecules. At the other extreme, the coordination of Mg 2+ in the first solvation shell would have to drop below four in order for proton release to occur, and because such events are going to be highly improbably, this may account for the very weak Lewis acidity of Mg 2+ .

Many simulations have demonstrated the presence of transient (ps) fluctuations in solvent shell occupation (20)(21)(22)(23) and quantitative evidence of the displacement of water molecules comes from experimental exchange rates recorded for molecules within the first coordination sphere (5,11,24). Using data available for the reaction H 2 O  H + + OHit can easily be shown that the half life of a water molecule in the liquid phase with respect to autoprotolysis is of the order of 10 4 s (25). Assuming this number scales (very approximately!) with pK h and for a salt concentration of 1 mol l -1 , then following an analysis given by Stillinger (25), estimates of the timescale ( f ) over which fluctuations of the type discussed above need to occur in order to maintain a particular level of acidity, are summarised in Table 1. The assumption being made here is that the reverse reaction in (1) is diffusion-controlled (~10 11 l mol -1 s -1 ) in the aqueous phase irrespective of the metal cation. This is significant assumption, because unlike water, the ions diffusing together are both 6 positively charged. However, recent kinetic energy releases measurements recorded for reaction (3) give some reflection of the magnitude of the reverse activation barrier as determined by the degree of repulsion between the two separating charges (10). As measured, the gas phase barriers at 1-2 eV are clearly too large to be surmounted under thermal conditions; however, for ion encounters taking place in water these values will drop by a factor of ~ 80, which brings even the largest value down to < 2 kT. There is also a systematic decline in energy release as the complexes increase in size, and this can be attributed to a gradual increase in separation between the MOH + unit and the position from which the solvated proton is released (10). For every factor of 10 drop in the value of the association rate coefficient,  f will increase by the same amount. In effect, the equilibrium shifts to the right and therefore fewer fluctuations are needed to maintain a specific pK h value.

Also given in Table 1 are exchange times for water molecules in the first coordination sphere; these numbers are not used as part of the calculation, but give an approximate measure of residence time and can place the required timescale for solvent fluctuation in context (5,11,24). Taking, for example Cu 2+ , the exchange time is ~ 10 -10 s, whereas for the reaction Cu 2+ H 2 O  Cu 2+ OH -+ H + to maintain a pK h of ~7 would require solvation shell fluctuations on a timescale of ~ 10 -4 s. Similarly, to maintain a pK h of ~11 in an aqueous solution of Mg 2+ would require solvent shell fluctuations every ~2.5 s that are sufficient to bring the water molecule occupancy below 4 (n s ); again this number is to be compared with an exchange time of ~ 10 -6 s. The only obvious discrepancy in Table 6 is Sn 2+ ; however, recent computer simulations have given mean residence times for water of the order of 10 -9 s (26,27), which would appear to be more appropriate. However, first-shell exchange times may not always be a good indication of behaviour, since our gas phase results show that the number of solvation shells over which an ion has influence can be sufficiently large that the displacement of solvent molecules in the second and quite possibly the third shell is going to be sufficient to promote hydrolysis. Although solvent exchange times might have been expected to provide a measure of the timescales for the type of transient fluctuation required in solvent occupancy to affect charge density and, hence promote hydrolysis, there is no clear correlation between those quantities and pK h . Probably what is most significant is the result that  f can be up to six orders of magnitude longer that the exchange or mean residence times for water molecules, which in turn, reflects the rare and rather extreme event required, for example, to displace 3 water molecules from the primary shell of Mg 2+ .

Results presented previously showed evidence of a remarkable correlation between the behaviour of metal dications in the gas phase and properties they exhibit when in aqueous solution. The molecular perspective afforded by this study has made it possible to offer a model of Lewis acidity in terms of an assembly of solvent molecules over which a metal ion has influence when in solution, and that fluctuations in the number of molecules within this grouping can promote Lewis acidity.

Answer: The ability of metal ions to generate protons in aqueous solution is of fundamental significance to many processes in chemistry and biochemistry. Numerous attempts have been made to categorise the event in a way that reflects the physical properties of the ions involved; however, several metal ions, including Pb(II) and Sn(II) frequently fail to conform.Here it is proposed that an intrinsic instability exhibited by metal ions associated with water molecules in the gas phase, can offer insight into the ability of the same ions to promote the release of protons in aqueous solution. It has already been shown that the gas phase results overlap with other methods that have traditionally been used to classify the behavior of metal ions in solution, e.g. HASB and the Irving-Williams series. To account for the Lewis acidity of metal ions in solution, a simple model based on fluctuations in solvent shell occupancy is proposed.


Question:
You will be presented with the full text of a biomedical research paper. Please write an abstract for this paper. Your response should include the abstract and no additional text.

Paper text:
superficial leiomyosarcomas are rare malignant tumors that account for only 510% of all soft tissue sarcomas .
they can be subdivided into two types according to its primary site of origin : deep subcutaneous and superficial cutaneous types .
primary cutaneous leiomyosarcoma ( pcl ) is a rare subtype with few isolated case reports and occasional case series described in the literature .
we report the clinical , histopathological and immunohistochemical findings in a 70-year - old male patient with pcl arising in the right leg .
a 70-year - old male patient presented with a painful nodule in the right leg , which had been progressively increasing in size for 4 months . on palpation , an irregular , firm , tender exophytic swelling , measuring 5 cm  5 cm , with overlying skin showing ulceration was noted on the lateral aspect of the lower one third of the right leg [ figure 1a ] .
his past history was significant of a trauma and subsequent non - healing ulcer formation at the same site in the right leg .
( a ) clinical photograph showing an irregular , exophytic swelling , measuring 5 cm  5 cm , with overlying skin showing ulceration on the lateral aspect of the lower one - third of the right leg .
( c ) gross photograph showing greyish white , solid , homogenous and fleshy cut surface of the irregular tumor mass measuring 5 cm  5 cm  2.5 cm systemic examination and investigations , including complete blood count , fasting blood sugar level , liver function test and renal function test , were within normal limits .
hepatitis b virus surface antigen and human immunodeficiency virus enzyme - linked immunosorbent assay were non - reactive .
a clinical diagnosis of squamous cell carcinoma was considered and fine needle aspiration cytology of the swelling was requested .
fine needle aspiration cytology of the same was reported as a spindle cell neoplasm with suspicion of malignancy .
the swelling was excised with a 5 cm resection margin and submitted for histopathological examination [ figure 1b ] .
gross inspection revealed a grey brown , irregular , nodular soft tissue mass , measuring 5 cm  5 cm  2.5 cm and partly covered with skin .
the cut surface of the mass was greyish white , solid , homogenous and fleshy [ figure 1c ] .
the neoplasm was composed of bundles of elongated spindle cells arranged in interlacing fascicles , with intensely pink , fibrillary cytoplasm and pleomorphic nuclei with coarse irregularly dispersed chromatin .
mitosis , including atypical , amounting to 22 mitotic figures per 10 high power fields and multinucleate tumor giant cells , was evident .
( a ) light microscopy revealed a dermal neoplasm with extension into the subcutaneous tissue ( h & e , 40 ) .
( b ) neoplasm composed of interlacing fascicles of elongated spindle cells ( h & e , 100 ) .
( c ) tumor cells are spindle shaped with intensely pink , fibrillary cytoplasm and pleomorphic hyperchromatic nuclei frequently exhibiting atypical mitosis ( black arrow ) ( h & e , 400 ) .
( d ) tumor cells with markedly pleomorphic nuclei and multinucleate tumor giant cell ( inset ) ( h & e , 400 ) a provisional diagnosis of spindle cell malignant neoplasm of the skin , which typically includes a host of diagnostic possibility , namely fibrosarcoma , leiomyosarcoma , malignant peripheral nerve sheath tumor , monophasic synovial sarcoma , malignant fibrous histiocytoma and spindle cell variant of squamous cell carcinoma , was considered and immunohistochemistry was advised for confirmation .
on immunohistochemistry , tumor cells showed strong immunopositivity for vimentin , muscle - specific actin ( msa ) , smooth muscle actin ( sma ) , caldesmon and desmin and negative for pancytokeratin , epithelial membrane antigen ( ema ) , myogenin , cd34 and s-100 protein [ figure 3 ] .
immunohistochemical staining : neoplastic cells showing positive immunostaining for ( a ) vimentin ( vimentin , 400 ) , ( b ) caldesmon ( caldesmon , 400 ) , ( c ) muscle - specific actin ( msa , 400 ) and ( d ) smooth muscle actin ( sma , 400 ) based on the immunophenotypic features , a final diagnosis of pcl was rendered .
the patient is currently on periodic follow - up since 1 year and no recurrence or metastasis has been identified so far .
although pcl most commonly arises in the extremities , particularly hair bearing surfaces , it may occur at any anatomic site on the body .
most case series described in the literature report a predilection for the middle aged to elderly male . in a large case series reported by fields and helwig ,
95% of the patients with pcl presented with a solitary nodule with a median size of 1.8 cm at presentation .
pain was reported by 24% of their patients at presentation , whereas pain could be elicited on pressure in an additional 27% of the patients .
histologically , pcl is characterized by a poorly circumscribed proliferation of interwoven fascicles of spindle shaped atypical myomatous cells that merge with a collagenous stroma .
mitosis , equivalent to one or more per 10 high - power fields , high cellularity and bizarre myomatous cells are the generally accepted criteria for malignancy .
described two growth patterns : a nodular pattern characterized by high cellularity , prominent nuclear atypia , conspicuous mitosis and a diffuse pattern that is less cellular , well differentiated and inconspicuous mitosis .
morphologic differential diagnosis includes a galaxy of other malignant spindle cell neoplasms , namely desmoplastic malignant melanoma , spindle cell synovial sarcoma , spindle cell angiosarcoma , fibrosarcoma , malignant fibrous histiocytoma and malignant peripheral nerve sheath tumor .
cutaneous leiomyosarcoma often exhibit immunophenotypic polymorphism , thereby mandating the use of a large panel of antibodies .
however , none of these markers is absolutely specific for smooth muscle , and positivity for two of these markers is more supportive of leiomyosarcoma .
jensen et al . identified several poor prognostic factors , namely tumor size 5 cm , acral location , deep localization with fascia involvement and high histological grade .
cutaneous leiomyosarcomas have fewer incidences of local recurrence ( 30 - 50% ) and negligible potential for distant metastases ( 010% ) . in contrast
, subcutaneous leiomyosarcomas may develop local recurrence in about 4060% and distant metastasis in 2060% of patients .
a wide local excision with a 35 cm margin is usually an effective treatment for pcl .
, pcl is a rare entity that must be borne in mind when encountered with a malignant spindle cell neoplasm of the skin and usually requires a panel of immunohistochemical markers to distinguish it from other cutaneous malignancies with spindle cell morphology .

Answer:
primary cutaneous leiomyosarcoma ( pcl ) is an exceedingly uncommon malignant superficial soft tissue sarcoma with a predilection for middle - aged to elderly male .
 morphologic differential diagnosis includes a host of other malignant spindle cell neoplasms , thereby necessitating the use of a panel of immunohistochemical markers to arrive at a definitive diagnosis .
 we report a case of pcl arising in the right leg of a 70-year - old male .


Question:
You will be presented with the full text of a biomedical research paper. Please write an abstract for this paper. Your response should include the abstract and no additional text.

Paper text:
during the early years that followed the discovery of x - ray , radiographers were unintentionally , incautious when dealing with it because of its unknown biological harmful effects .
many cases of cancer , sterility and death due to x - ray / radiation toxicity were documented during the early years of the 20 century .
for example , in 1907 , 6 out of 11 cases with x - ray - induced caners died .
moreover , many early workers in the field of dentistry suffered from radiation - induced ulceration , dermatitis and malignant tumors in their fingers . with strict compliance to the radiation protection guidelines , issued by the international commission on radiological protection ( icrp ) , diagnostic radiography is considered a safe practice .
, no other reports addressing the disastrous effects of x - ray radiation have been documented in the literature since 1960s . the present report , however , documents a case of thumbs carcinoma of a dental radiographer due to his neglect of radiation protection guidelines .
in august 2010 , a 49-year - old male working as a dental radiographer , lost his distal phalanges of both thumbs as a result of development of squamous cell carcinoma , due to neglect of the guidelines of protection related to x - ray imaging .
he was appointed in 1994 by the radiology division , primarily as an in - charge clerk within the oral medicine department ( faculty of dentistry , damascus university ) . as a school graduate with an intermediate certificate ,
his main task was merely to monitor the radiographic equipment . given that there was only one radiographic technician at that time , it was decided in 1995 to train him on how to use the dental x - ray machines and how to radiograph patients .
he was warned about the radiation risks and thoroughly educated on the appropriate protection standards .
on the other hand , he was accustomed to handling the periapical films with his thumb fingers . in 2003
although it was asymptomatic , he considered it as a traumatic ulcer and hence willingly neglected it for a period , which under normal circumstances would be considerably enough for such an ulcer to heal .
subsequently he then experimented with various courses of local and systemic antibiotic , but the ulcer did not show any signs of healing . based on his judgment
, it was asymptomatic and unprogressive , and accordingly he perceived to be a normal exfoliation , the result of his long - term handling of chemical processing solutions . in august 2010
( after 15 years of handling dental x - ray ) , he noticed a discharge oozing from his right thumb . by that time , he also took notice of a similar ulcer in his left thumb .
he consulted the professors in the department who in turn referred him to a general surgeon . on plane hand radiographs ,
an erosion of the distal phalanges of both thumbs was clearly evident [ figures 1 and 2 ] .
consequently , the surgeon planned to excise the discharging ulcerative lesion of the right thumb and to submit it for histopathological diagnosis , which clearly revealed squamous cell carcinoma grade ii [ figure 3 ] . based on such a diagnosis ,
the surgeon decided to excise the distal phalanges of both thumbs with tumor free - margins [ figure 4 ] .
out of ethical consideration , the radiographer was well - informed about the intent to publish his case and hereby he signed an informed consent .
plane hand radiograph reveals bone erosion in the right thumbs distal phalanges plane hand radiograph reveals bone erosion in the left thumbs distal phalanges histopathologic microphotographs reveal squamous cell carcinoma ( [ a ] 40 and [ b ] 100 )
early x - ray machines needed to be set and repeatedly adjusted . to achieve this
, radiographers would place their hands between the actively radiating tube and the film plate to check if the apparatus was functioning and that it was well focused on the film . by practicing this for 12 years , dr . kells
was the first victim of dental x - ray radiation with numerous cancerous tumors on his fingers . by that time , the icrp published guidelines for radiation protection that have been updated from time to time . in syria ,
the atomic energy commission adopted these guidelines and has since strictly emphasized the importance of their application by public and private institutions .
one of the guidelines clearly states that the film should never be hand held by a member of the dental practice staff , even for patients with special needs . holding periapical films in the patient 's mouth is still practiced in modern dentistry , but , fortunately , is not common .
sixty per cent of australian dentists never do this , but 25% will do so less than once every month , and 1.5% might do so more than 10 times a month .
the radiation - risk is the function of the radiation dose which is expressed as an effective dose .
the national commission for radiation protection in the united states reports that the mean effective dose received by dental workers is 0.2 msv / year .
similarly , the national radiological protection board , in the uk estimates a mean level of < 0.1 msv / year . in dose limit terms for workers ,
the current effective dose limit is 100 msv in any consecutive 5 years with a maximum of 50 msv in any year .
these limits are based on guidance from the icrp , with the effective dose limit being set at a level at which the stochastic risk is considered to be at the limit of acceptability .
the probability of radiation - induced stochastic effects for the whole population is 7.3  10 /sv . the working load in the radiology division within the faculty ranges between 100 and 150 patients a day .
hence , the radiographer in the current report received a fraction of about 600900 sv / day ; 13.219.8 msv / month ; 158237 msv / year and 2.43.6 sv in 15 years .
overall , he was at a greater risk of getting a stochastic effect by 2.43.6 times compared to the whole population , as the probability of radiation - induced stochastic effect for this case ranges from 18  10   to 26  10 /sv .
some authorities claim that any dose of radiation has the potential to induce malignant changes , and there is no threshold dose below which radiation is predictably safe .
the risk of induction of fatal cancer or serious hereditary ill - health from dental intra - oral radiography was estimated to be 1 in 10 million ( 10 ) per exposure .
this increased the risk of inducing fatal cancer or serious hereditary ill - health to 46 in 100 ( 10 ) .
however , the risk - estimates depend on the shape and length of the collimator or position indicating devices ( pids ) .
the short and pointed cones with closed - end , such as that which had been used by the radiographer in this report for 13 years ( fiad , dr 554 , italy ) , have the greatest probability of a stochastic effect ( 1 in 26  10 ) in comparison to the rectangular or round ones .
the latter , which are open - ended and have been used for the last 2 years of the radiographer 's work ( ardet s.r.l buccinasco [ mi ] orix 70 , italy ) , have a probability of a stochastic effect ranging from 1 in 4.6  10   to 1 in 23  10   according to the length .
overall , the shielded open - end pids , both round and rectangular in shape , have become more widely used during the past 40 years because of the reported decrease in patient exposure that is achieved . in general ,
dental radiography has a little dose and risk for the individual patient and dental workers provided that the principles of protection are applied ; it is less dangerous in comparison to a few days of natural background radiation to which we are all constantly exposed .
dental radiography doses and risks are minimal unless dealt without being cautious , which is the case of the radiographer presented here .

Answer:
dealing with diagnostic x - ray radiation may result in serious health problems , unless protection guidelines are followed .
 this became prevalent immediately a decade following the invention of x - ray radiation , where it had not been known that the accumulative exposure to x - ray radiation may carry huge health hazards .
 the reoccurrence of various fatal cancer cases compelled the concerned health authorities to develop safety standards to be followed by all x - ray clinics and technicians worldwide .
 this report documents the clinical case of a dental radiographer , who developed thumbs carcinoma after 15 years of practicing the profession , most likely due to his neglect of the x - ray radiation protection guidelines .


Question:
You will be presented with the full text of a biomedical research paper. Please write an abstract for this paper. Your response should include the abstract and no additional text.

Paper text:
the typical clinical presentation of poi is pain in the right side of the abdomen , and this may lead to a misdiagnosis of acute appendicitis or cholecystitis . here , we present a case of poi , with pain in the left lower quadrant .
a 50-year - old woman admitted to the emergency room with a history of worsening abdominal pain for 5 days .
the pain began in the upper abdomen and later localized to the left lower quadrant , and the pain intensity exacerbated with activities .
the pain was sharp and constant in nature without nausea or vomiting . on physical examination , the patient was febrile with a temperature of 38.1c and had severe left lower quadrant tenderness and abdominal rigidity .
the previous history included an open ectopic pregnancy surgery in 1996 , and no atrial fibrillation , no venous thrombosis , no contraceptive , or aspirin usage .
the laboratory test showed white blood cell 9.71  10/l , d - dimer 1.58 mg / l , and no other abnormalities .
an abdominal computed tomography ( ct ) was performed and showed a left ovarian cyst measuring 6.0 cm  4.5 cm with no other remarkable findings [ figure 1a ] .
after about 1 day , the patient complained of worsening abdominal pain and absence of passage of feces and gas .
( a ) axial image showed a left ovarian cyst measuring 6.0 cm  4.5 cm .
median sagittal section showed an increased fat - density mass consequently , we performed laparoscopic exploration . during the procedure , we found a segment of congested necrotic omentum adhering to the abdominal wall with a segment of small intestine [ figure 2a ] , bloody ascites ( 200 ml ) accumulated in the abdominal cavity [ figure 2b ] , and an ovarian cyst measuring 6.0 cm  4.5 cm in pelvic cavity [ figure 2c ] .
we resected the nonviable omental segment , and the gynecologist removed the ovarian cyst using laparoscopic procedures .
( b ) a dark purple mass on the left side in the lower part of the omentum and bloody ascites in the left abdomen . ( c )
a huge ovarian cyst by reanalyzing the preoperative ct , a segmental fat mass with an increased density was noted in the left lower quadrant which was consistent with the intraoperative findings [ figure 1b ] .
final pathological examination revealed hemorrhagic infiltrations , thrombosis of the tissue , acute inflammatory cellular infiltrate , and fibrinoid necrosis , and poi was diagnosed [ figure 3 ] .
histological examination of the resected nonviable omentum revealed hemorrhagic infiltrations , thrombosis of the tissue , acute inflammatory cellular infiltrate , and fibrinoid necrosis
up till now , only a few hundred cases have been published in the english literature .
susceptible factors include ( 1 ) anatomic malformations such as a bifid or accessory omentum causing the spontaneous torsion , ( 2 ) sudden movement , violent exercise , and hyperperistalsis , and ( 3 ) obesity .
most authors support the hypothesis that it is associated with an anomalous and fragile blood supply of the right lower portion of the omentum , which is consequently susceptible to infarction .
thus , 90% of all the cases have initial pain in the right side of the abdomen .
our patient had pain in the left lower quadrant , so we did not include poi in the differential diagnosis spectrum .
poi has no early specific signs and is often characterized by progressive , persistent abdominal pain .
clinical features include unspecific gastrointestinal symptoms , slightly febrile , and mild leukocytosis . in the present case ,
d - dimer can be used as an objective parameter in the differential diagnosis of poi as it is used in other thromboembolic diseases .
the most diagnostic finding is an ill - defined heterogeneous fat density with surrounding inflammatory changes . by retrospective reanalysis of the preoperative ct in this study ,
ultrasound is specific but not sensitive for diagnosing poi ; suspected imaging features include hyperechoic , incompressible , ovoid mass , and detectable in < 50% of cases , even when reviewed retrospectively .
two patients underwent surgery , one because of the absence of spontaneous regression and the other because of extremely severe clinical symptoms . in the other four patients ,
conservative management was given and successful . if a confirmed diagnosis of poi can be made with the typical clinical signs and imaging studies , conservative treatment is the first - line therapy during the first 2448 h while resuscitation and antibiotics are initiated .
however , if the diagnosis is in doubt or if conservative treatment fails , laparoscopy should be performed without delay . as in the present case ,
the pain was not relieved after conservative treatment for 24 h. intestinal obstruction occurred as a segment of small intestine adhered to the abdominal wall .
poi should be considered in the differential diagnosis of any patient presenting with acute abdominal pain .
laparoscopic exploration should be performed if new symptoms occur or do not relieve within 2448 h. there are no conflicts of interest .

Answer:
primary omental infarction ( poi ) is a rare cause of acute abdomen .
 most patients have aggravating abdominal pain without gastrointestinal symptoms . here , we report a case of omental infarction in a 50-year - old woman , who had left abdominal pain and intestinal obstruction . preoperative computed tomography ( ct ) of the abdomen showed a left ovarian cyst measuring 6.0 cm  4.5 cm but otherwise seemed normal initially .
 the white blood cell count was 9.71  109/l , and d - dimer was 1.58 mg / l .
 laparoscopic exploration was performed 1 day after admission because of peritonitis and intestinal obstruction . during the exploration
 , a segment of congested necrotic omentum was found adhering to the abdominal wall with a segment of small intestine .
 bloody ascites was also observed in the abdominal cavity .
 we resected the nonviable segmental omentum , and the ovarian cyst was removed by the gynecologist using laparoscopic procedures .
 final pathological findings confirmed poi . while reanalyzing the preoperative ct , a segmental fat mass with an increased density
 was noted in the left lower quadrant , which was consistent with the intraoperative view 6 days after surgery .
 the patient recovered uneventfully and was discharged .


Question:
You will be presented with the full text of a biomedical research paper. Please write an abstract for this paper. Your response should include the abstract and no additional text.

Paper text:
six hundred officers were recruited from the police departments of new york , ny , and oakland and san jose , calif , usa . fifty - two percent of the sample was caucasian .
the mean age was 36,50 years ( standard deviation [ sd])=6.96 ) . years in the police force everaged 12.37 ( sd=6.78 ) .
number of exposure to critical incidents ranged from 2 to 670 ( mean [ m]= 171.27 , sd=130.93).the incident selected for completing the questionnaires had occured on average 6.50 ( sd= 5.11 ) years ago .
the peritraumatic distress scale ( pds ) was used to assess emotional , cognitive , and physical reactions occuring during a critical incident and immediatly after .
dissociation at the time of the incident was measured with the peritraumatic dissociative experience questionnaire ( pdeq).the impact of event scale - revised ( ies - r ) was used to measure ptsd symptoms in the last 7 days .
the mississippi scale ( mcs ) was used to measure ptsd and associated symptoms since the critical incident .

we conducted a cronbach alpha reliability analysis and an oblique principal factor analysis with promax rotation on the items of the pds .
two series of hierarchical multiple regression analyses were conducted using sociodemographics ( gender , ethnicity , years of service ) , exposure , the pdeq and pds as predictors of either the mcs or the ies - r
six hundred officers were recruited from the police departments of new york , ny , and oakland and san jose , calif , usa . fifty - two percent of the sample was caucasian .
the mean age was 36,50 years ( standard deviation [ sd])=6.96 ) . years in the police force everaged 12.37 ( sd=6.78 ) .
number of exposure to critical incidents ranged from 2 to 670 ( mean [ m]= 171.27 , sd=130.93).the incident selected for completing the questionnaires had occured on average 6.50 ( sd= 5.11 ) years ago .
the peritraumatic distress scale ( pds ) was used to assess emotional , cognitive , and physical reactions occuring during a critical incident and immediatly after .
dissociation at the time of the incident was measured with the peritraumatic dissociative experience questionnaire ( pdeq).the impact of event scale - revised ( ies - r ) was used to measure ptsd symptoms in the last 7 days .
the mississippi scale ( mcs ) was used to measure ptsd and associated symptoms since the critical incident .

we conducted a cronbach alpha reliability analysis and an oblique principal factor analysis with promax rotation on the items of the pds .
two series of hierarchical multiple regression analyses were conducted using sociodemographics ( gender , ethnicity , years of service ) , exposure , the pdeq and pds as predictors of either the mcs or the ies - r
the pds scores ranged from 0.10 to 3.57 and the mean was 1.37 ( sd=0.56 ) .
the scale was internally consistent ( =0.80 ) and showed strong convergent validity with the pdeq , r(599)=0.55 , p<0.001 .
the pds factor solution is presented in table i items defining factor 1 included dysphoric emotions such as helplessness , sadness and grief , frustration and anger , and horror .
factor 2 was mostly defined by items related to loss of safety and arousal , such as being afraid , thinking one might die , and having intense bodily reactions ( sweating , shaking , heart - pounding ) .
items loading on factor 3 were related to the loss of positive beliefs about the self and others , such as thinking that one had done all he or she could during the critical incident , not felling prepared by one 's experience , and not believing tha others understood .
we labeled the factors negative emotions , perceived life threat and bodily arousal , and appraisal .
the sum of communality estimates was 7.58 , explaining 38% of the communality estimates was 7.58 , explaining 38% of the total variance and 93% of trace .
intercorrelations among the pds factors were low , ranging from -0.25 to 0.12 ( p<0.05 ) .
the low pds factor intercorrelation coupled with correlations of 0.17 to 0.42 ( p<0.001 ) with the outcome measures ( ies - r and mcs ) suggest that various forms of peritraumatic distress , as captured by the pds , can lead to the development of ptsd symptoms .
two stepwise regression analyses ( not fully reported here ) were conducted . in predicting the mcs and ies - r ,
the pdeq , entered in the second step , explained 20% and 16% of unique variance on the mcs and ies - r , respectively . entering the pds in step 3 explained 11% and 8% unique variance on the mcs and ies - r , respectively .
we repeated this set of analyses with the inclusion order of the pdeq and pds reversed .
entered in the second step , the pds explained 29% and 17% of unique variance on the mcs and ies - r , respectively . entered in the third step , the pdeq explained 3% of unique variance on both the mcs and the ies - r .
the items and factors of the pds provide insight as to what some of the salient peritraumatic dimensions may be , in addition to peritraumatic dissociation . in this study ,
the pds explained a significant amount of variance over and above peritraumatic dissociation which is currently considered among the mos powerful predictors of ptsd symptoms .
test - retest data for the pds is currently being gathered as well as data from individuals not working in the police . in future
, it would be useful to investigate prospectively the power of the pds in predicting ptsd diagnosis rather than symptoms , as well as other trauma - related disorders .

Answer: posttraumatic stress disorder ( ptsd ) occurs when significant intrusion , avoidance , and hyperarousal symptoms are manifest for at least 1 month following exposure to a traumatic event , with at least 1 month following exposure to a traumatic event , with at least 1 month elapsed betwenn the event and the diagnossis ( diagnostic and statistical manual of mental disorders , 4th edition , 1994 [ dsm - iv]).1 however , such symptoms are not necessarily manifest in the immediate aftermath of the trauman,2 nor does their intial presence strongly predict who will develop ptsd.3 one immediate response to trauma which has been convicingly linked to ptsd symptoms is peritraumatic dissociation.4 in this poster , we briefly introduce a new scale assessing immediate responses distinct from peritraumatic dissociation , and we examine its power to predict ptsd symptoms .


Question:
You will be presented with the full text of a biomedical research paper. Please write an abstract for this paper. Your response should include the abstract and no additional text.

Paper text:
it is very important to distinguish m. abscessus from other nontubercular mycobacteria ( ntm ) as antimycobacterial therapy is significantly more complex .
a 53-year - old male patient from gujarat ( india ) , with a history of hypertension , diabetes mellitus , hypothyroidism , and a stable dilated cardiomyopathy was shifted to our hospital with a prolonged pyrexia , which had remained undiagnosed and unresponsive to standard antimicrobial treatment .
a coronary angiography had been performed 8 weeks earlier , which showed normal coronary anatomy .
three weeks following the angiography , the patient developed moderate- to high - grade fever for which standard investigations , routine blood cultures , and imaging were performed and were inconclusive .
he was transferred to our care 6 weeks into his febrile illness with no clear diagnosis . on examination ,
the patient was febrile , toxic , and had an early diastolic murmur in the aortic area .
the investigations revealed hemoglobin 8.3 g / dl , white blood cells 9200 cells / mm , platelets 2,23,000/mm , serum creatinine level 2.2 mg / dl , and erythrocyte sedimentation rate 88 mm / h .
urine analysis showed 3 - 5 red blood cells ( rbcs)/high power field ( hpf ) and a raised 24-h urine protein of 1527 mg/24 h was also noted . on ultrasonography ,
there was mild hepatosplenomegaly , but there was no evidence of focal lesions in the spleen or liver .
chest roentgenogram revealed mildly prominent pulmonary vasculature with cardiomegaly but no significant lung parenchymal pathology .
the two - dimensional echocardiography ( 2d echo ) done at previous hospital showed left ventricular ejection fraction ( lvef ) of 30% , normal heart valves , and global hypokinesia .
a repeat 2d echo at our center showed an evidence of mild aortic regurgitation with three discrete small mobile vegetations on the left and right coronary cusps of the aortic valve .
choroidal infiltrates as a stigmata of infective emboli were noted , but there was no evidence of embolization to skin or any other organ .
double stranded antibody ( anti - dsdna ) , and anti  nucleophilic cytoplasmic antibodies ( anti - anca ) were negative and complement levels ( c3 and c4 ) were within the normal range .
the patient was treated for heart failure and was started on ceftriaxone at a dose of 1 g twice daily intravenously as empirical treatment for infective endocarditis .
bactec myco / f lytic medium was then used , which demonstrated the rapidly growing organisms as ntm .
linezolid and clarithromycin were empirically added while awaiting the sensitivity and speciation of the ntm .
meanwhile , species identification using the line probe assay technique revealed the organism to be m. abscessus and drug sensitivities were subsequently obtained .
the organism was found to be sensitive to amikacin , clarithromycin , linezolid , and tobramycin , with intermediate sensitivity to cefoxitin but was found to be resistant to doxycycline , imipenem , cefepime , ceftriaxone , minocycline , and amox  clavulanic acid .
the two antibiotics ( linezolid and clarithromycin ) were continued and the other sensitive drugs isoniazid , ethambutol , and cefoxitin were added to the treatment regimen .
the patient defervesced for the first time after 7 weeks of continuous fever 1 week into the above treatment .
linezolid was withheld for 10 days in view of significant bone marrow suppression but was later reinstituted in lower doses .
after 3 weeks of therapy with a combination of five antibiotics , the creatinine stabilized at 2.6 mg / dl having previously reached a peak of 3.6 mg / dl .
the valvular vegetations , however , were present and blood cultures still grew the same mycobacteria despite the patient having defervesced .
aortic valve replacement surgery was considered but was withheld in view of multiple comorbidities and patient 's reluctance to undergo any procedure .
a repeat 2d echo at 4 weeks post treatment showed no change in the vegetation size and the patient was discharged on request on all five antimycobacterial antibiotics .
subsequently , the patient developed worsening cardiac failure and died of pulmonary edema and renal dysfunction despite aggressive medical management in a local intensive care unit .
postprocedure mycobacterial infections have been often reported , especially in india where glutaraldehyde is used as a sterilizing solution for surgical and other equipments .
risk factors for bacteremia following catheterization include obesity , duration of the procedure , the number of balloons used , and the number of skin punctures performed .
infections complicating coronary angiography include sepsis , endocarditis , suppurative pancarditis , stent infection , septic arthritis , epidural abscess , necrotizing fasciitis , and groin wound infection .
the most common causative organism of bacteremia following cardiac catheterization is staphylococcus aureus , particularly in the obese .
native valve endocarditis with ntm such as m. abscessus is rare and often missed without appropriate blood cultures . in cases of postprocedure endocarditis ,
early diagnosis and prolonged combination therapy are obligatory to minimize mortality , as m. abscessus is inherently resistant to multiple antibiotics .
although there are no specific drug protocols for treatment of pulmonary m. abscessus disease , a macrolide - based regimen is often used combined with surgical debridement for successful therapy .
evidence - based management for other nonpulmonary diseases and specifically for m. abscessus endocarditis is lacking due to sheer rarity of the condition and treatment is based on in vitro drug susceptibility .
typically , antibiotics with maximum in vitro activity against m. abscessus isolates include amikacin , clarithromycin , tigecycline , and cefoxitin . to a lesser extent ,
combination therapy is mandatory and should be administered for at least 2 - 4 months .
tigecycline and linezolid are newer antibiotics with efficacy against m. abscessus and the recommended treatment length with these drugs is 6 - 12 months . among the carbapenems ,
clarithromycin and linezolid were used in combination as aminoglycosides were contraindicated due to renal failure .
the cause of the raised creatinine was thought to be multifactorial , secondary to diabetic nephropathy , hypertension , and congestive cardiac failure .
the possibility of septic emboli causing nephritis seems low owing to only 3 - 5 rbcs / hpf in urine .
isoniazid and ethambutol were added as standard antituberculous therapy with the hope of some benefit in such a desperate situation .
m. abscessus infection is not always considered a medically curable condition , but prolonged antibiotic therapy may result in chronic suppression of the disease . in vitro drug susceptibility patterns do not always correlate with clinical responses and measurements of minimum inhibitory concentrations of antibiotics do not always predict their therapeutic effects .
endocarditis caused by m. abscessus generally has a very poor prognosis despite combination antimicrobial therapy , as only two of the 10 documented cases described in the literature have survived after treatment .
surgical intervention to replace the infected valve would have been worth attempting if the patient had been willing . however , in view of the dismal treatment outcomes shown by previous studies , it remains uncertain if early institution of appropriate therapy or valve replacement would have altered the ultimately fatal outcome with this pathogen .
nosocomial infection control needs to be strengthened particularly at smaller centres where complex interventions are increasingly being conducted .

Answer:
mycobacterium abscessus is an unusual cause of infection in immunocompetent patients .
 the intrinsic and acquired resistance of this organism to multiple antibiotics is a major issue in planning treatment regimens .
 we report a case of m. abscessus endocarditis of the native aortic valve in an immunocompetent patient following coronary angiography with a fatal outcome .
 the case highlights an unfortunate intervention  related nosocomial infection and the difficulties in chemotherapeutic options for this organism , particularly in the presence of renal failure .