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:
in some clinical situations , such as root canal overinstrumentation , apical resorption and teeth with open apices , there may be extrusion of the filling material , either gutta - percha , root canal sealer or both , due to the difficulty or impossibility to lock the master gutta - percha cone . in these situations ,
fabrication of an apical plug with calcium hydroxide and , more recently , with mineral trioxide aggregate ( mta ) has been suggested2,4,13,21,25,26 .
mta was introduced in the early 1990 's as an experimental material developed by dr .
mahmoud torabinejad at loma linda university , usa . this material was originally indicated as a retrograde filling material for use in endodontic surgery and cases of intraradicular and furcal perforations18 . since then
, it has been used in different clinical situations , such as communicating internal and external resorptions , as capping material in mechanically exposed pulps , as intracoronal barrier during internal bleaching of endodontically treated teeth , and as apical plug in case of difficulty to lock the master gutta - percha cone4 .
these indications of mta are related to the possibility of use in moist environments , as in most aforementioned indications , and mainly to its biocompatibility4,26 .
the sealing ability of mta apical plug and its thickness have been investigated by several authors2,13,16,17,20,21,26 .
four - millimeter - thick plugs have been shown to be the most efficient with respect to root canal sealing ability and resistance to displacement13,20,21,26 .
all of these studies have sought an alternative to mta apical plug as well as its most appropriate thickness .
wucherpfennig and green27 ( 1999 ) have called the attention to the fact that mta and portland cement were similar materials .
other studies were conducted and confirmed this similarity by means of microbiological , chemical , physical and biological behavior tests1,5,8,10,11,15,23 .
the purpose of this study was to evaluate the sealing ability of apical plugs made of white and gray mta - angelus ( angelus solues em odontologia , londrina , pr , brazil ) and white portland cement ( votorantim cimentos , votorantim , so paulo , sp , brazil ) placed via the root canal and having different thicknesses ( 2 , 5 and 7 mm ) .
this study was approved by the institutional review board of the dental school of bauru , university of so paulo , brazil .
ninety extracted human single - rooted teeth with intact roots and completely formed apices were used .
the teeth were obtained from the files of the department of endodontics of the dental school of bauru and were kept in 10 % aqueous formalin solution .
the dental crowns were sectioned at the cementoenamel junction with a low - speed diamond saw ( kg sorensen , so paulo , sp , brazil ) under continuous water spray to obtain access to the root canal .
the root canal length was determined by inserting a size 15 k - file ( dentsply - maillefer instruments sa , ballaigues , switzerland ) into the canal until its tip reached the apical foramen . the working length was established by subtracting 1 mm from this measurement .
the stepback technique was employed and the root canal was flared using a size 60 k - file to the working length .
instrumentation was aided by irrigation with 1 ml of 1% sodium hypochlorite solution ( biodinmica qumica e farmacutica ltda , ibipor , pr , brazil ) alternated with the sequence of instruments , followed by a final flushing with 1 ml of sterile water .
the teeth were assigned to 3 groups ( n=30 ) , according to the material used for fabrication of the apical plugs : group a = placement of gray mta - angelus plugs ; group b = placement of white mta - angelus plugs ; group c = placement of white portland cement plugs .
the groups were further subdivided into groups of 10 teeth each , according to the thickness of the apical plugs , namely 2 , 5 and 7 mm ( table 1 ) . before standardization of the foraminal opening
, the roots were made impermeable by application of a layer of epoxy adhesive ( araldite - ciba - geigy s.a .
, taboo da serra , sp , brazil ) , followed by two coats of nail polish ( cosbra cosmeticos ltda . , so paulo , sp , brazil ) .
the foramen diameter was standardized by inserting the 40 k - file 1 mm beyond the apical foramen , so that only the apical opening would not be impermeable . for fabrication of the apical plugs ,
the tested materials were applied with a size 4 lentulo spiral ( dentsply - maillefer instruments sa , ballaigues , switzerland ) at the apical end of the root , trying to fill it completely .
the material was condensed with the tip of a size 40 k - file involved in cotton for achievement of the plug19 .
next , using a size 40 k - file with a rubber stop positioned 2 , 5 and 7 mm shorter than the root canal length , the excess material was removed for fabrication of 2- , 5- and 7-mm - thick apical plugs , respectively .
finally , the root canal walls were cleaned with the tip of an instrument wrapped in moist cotton .
then , the canal entrances were sealed with epoxy adhesive and nail polish , and the roots were immersed in 0.2 % rhodamine b solution ( labsynth produtos para laboratrios ltda , diadema , sp , brazil ) at ph 7.0 for 72 hours at 37c . after this period , the roots were removed from the dye , washed in running water for 24 hours , had the impermeable coating scraped away and were washed for additional 12 hours .
the roots were then sectioned longitudinally in a buccolingual direction for exposure of the apical plugs , photographed with a digital camera ( canon eos rebel 300 d ) and analyzed by image tool software ( university of texas health science center , san antonio , tx , usa ) .

 table 2 shows the percent marginal leakage for the different materials for each plug thickness .
tables 3 , 4 and 5 show the results of the kruskal - wallis statistical test for comparison among groups a ( mta - angelus gray ) , b ( mta - angelus white ) and c ( white portland cement ) with respect to the plug thicknesses ( 2 , 5 and 7 mm ) . a statistically significant difference ( p<0.05 )
was observed between groups a and b as to the leakage in 2- mm - thick plugs , with better results for group a ( table 3 ) .
materials did not show statistically significant difference ( p>0.05 ) when groups with 5-mm - thick plugs were compared to each other ( table 4 ) . regarding the 7-mm - thick plugs , there was statistically significant difference ( p<0.05 ) between groups a and b and between groups b and c , with worst results for group b in both comparisons ( table 5 )
. in figure 1 shows the graphic presentation of percent marginal leakage ( 0.2% rhodamine b ) in the root canals , regarding the tested materials and plug thicknesses .
it is possible to verify that 2-mm - thick plugs yielded the least satisfactory results in all groups , whereas the 7-mm - thick plugs yielded the best results for groups a and c , yet not for group b , in which the 5-mm - plugs had the best results as to dye leakage .
this study investigated the sealing ability of gray mta , white mta and white portland cement used for fabrication of apical plugs , given that this procedure is often required in the clinical practice12,14,19 , mainly in cases where appropriate adaptation of the master gutta - percha cone is difficult .
torabinejad and chivian25 ( 1999 ) pointed out that the goal of an apical plug is to induce hard tissue formation , in order to prevent filling material extrusion in teeth with open apices .
the use of methylene blue in marginal sealing studies has been questioned , due to its incompatibility with alkaline substances , which may induce discoloration of the dye .
when calcium oxide is mixed with water , it results in the formation of calcium hydroxide , with a subsequent increase in ph , as previously demonstrated by duarte , et al.9 ( 2003 ) .
therefore , rhodamine b dye solution is more appropriate for evaluating the sealing ability of mta22,24 . in the present study , 5- and 7-mm - thick plugs
were more efficient for apical sealing than 2-mm - thick plugs , regardless of the material utilized ( table 1 and figure 1 ) , which is in agreement with the findings of previous2,13,21,26 . in group
b ( white mta ) , the 5-mm - thick plugs had better performance than the 2- and 7-mm - thick plugs , yet without statistically significant difference .
with regard to tested materials , no statistical difference was expected among them because the chemical components of mta and portland cement are the same , except for bismuth oxide , which provides radiopacity to mta8,10,11 .
camilleri , et al.7 ( 2005 ) evaluated the chemical constitution and biocompatibility of white and gray portland cement , white and gray mta , portland cement clinker without calcium sulfate and portland cement clinker without calcium sulfate with addition of bismuth oxide .
they concluded that the chemical composition of the tested materials is similar , primarily containing tricalcium silicate and dicalcium silicate .
the white cements differ from the gray cements by the small quantity of iron oxide ( feo ) , while mta differs from portland cement due to the presence of bismuth oxide .
there was no difference between white and gray mta , and the addition of bismuth oxide did not interfere with the biocompatibility of cements . in the present study , white mta showed poorer results than gray mta and white portland cement for all tested plug thicknesses ( table 1 ) .
asgary , et al.3 ( 2005 ) observed significant differences between gray and white mta , especially in the contents of aluminum trioxide ( al2o3 ) , magnesium oxide ( mgo ) and iron oxide ( feo ) .
however , these differences are not enough to explain the results of the present study , in which gray mta showed better results than white mta as to dye leakage .
matt , et al.21 ( 2004 ) observed similar results in their study , where apical plugs made with gray mta were more efficient than those made with white mta .
as to the fabrication of apical plugs , torabinejad and chivian25 ( 1999 ) recommended carrying the mta with a large amalgam carrier to the root canal and then condensing the material to the apical end of the root with pluggers or paper points .
sometimes , this procedure is difficult due to the root canal diameter and anatomy . in the present study ,
mta and portland cement were carried to the root canal with a size 4 lentulo spiral , according to the technique proposed by bramante , et al.6 ( 2004 ) .
the lentulo spiral is used to carry the mta in paste consistence more easily to the root canal end in a fast and correct manner .
another important factor is material condensation at the end of the root canal because the apical plug should resist the filling material .
this condensation is more effective when performed with a k - file compatible with the root canal diameter and with the tip wrapped in a cotton mesh .
cleaning of the root canal walls and removal of excess material must be performed with the same k - file wrapped in moist cotton in sterile saline , not to interfere with the proper root canal filling .
the findings of the present study showed that gray mta and portland cement had better sealing ability than white mta when used as apical plugs .
dye leakage was smaller for 5- and 7-mm - thick plugs compared to 2-mm - thick plugs .

Answer:
this study evaluated the sealing ability of apical plugs made of white and gray mta - angelus and white portland cement placed via the root canal and having different thicknesses ( 2 , 5 and 7 mm ) .
 ninety extracted human single - rooted teeth were instrumented using a size 40 k - file to standardize the foraminal opening by the stepback technique .
 the teeth were assigned to 3 groups ( n=30 ) , according to the material used for fabrication of the apical plugs : a = gray mta ; b = white mta ; c = white portland cement .
 the groups were subdivided into groups of 10 teeth each according to the apical plug thickness ( 2 , 5 and 7 mm ) .
 marginal apical dye leakage was assessed using 0.2% rhodamine b solution in which the specimens were immersed for 72 hours at 37c .
 the roots were sectioned longitudinally in a buccolingual direction for apical plug exposure , and digital photographs were taken and analyzed by image tool image - analysis software .
 data were analyzed statistically by kruskal - wallis and dunn 's tests .
 significance level was set at 5% .
 the least percent leakage was observed for 5- and 7-mm - thick plugs ( p<0.05 ) .
 no significant difference ( p>0.05 ) was found between gray mta and white portland cement . among the three materials analyzed , white mta presented the highest marginal leakage ( p<0.05 ) .
 the findings of the present study showed that gray mta and portland cement had better sealing ability than white mta when used as apical plugs .
 dye leakage was smaller for 5- and 7-mm - thick plugs compared to 2-mm - thick plugs .


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:
its prevalence varies among ethnic groups , but it affects approximately 13%   of the population in industrialised countries .
its clinical course can vary greatly in terms of morphology , distribution , and severity of the disease . in its commonest subtype
it is characterised by the formation of discrete , pink , scaly plaques occurring at various sites on the body .
although it can present at any age , it occurs most frequently between the ages of 15 and 20 and again between 50 and 60 years of age .
psoriasis has very significant psychosocial morbidity which appears independent of objective disease severity [ 3 , 4 ] .
it is also associated with an increased risk of cardiovascular disease and mortality [ 58 ] . indeed patients with psoriasis have almost twice the risk of cardiovascular disease when compared with normal controls [ 9 , 10 ] .
a number of studies have shown significantly increased rates of hypertension , dyslipidemia , diabetes mellitus , smoking , and excessive alcohol consumption in patients with psoriasis .
found that patients with severe psoriasis had an increased risk of diabetes ( odds ratio ( or ) , 1.62 ; 95% confidence interval ( ci ) , 1.32.01 ) , obesity ( or , 1.79 ; 95% ci , 1.552.05 ) , and smoking ( or , 1.31 ; 95% ci , 1.171.47 ) compared with controls .
prodanovich et al . also found a higher prevalence of these risk factors in patients with psoriasis .
however , even after controlling for these variables , they found a higher prevalence of ischemic heart disease ( or 1.78 ; 95% ci , 1.512.11 ) , cerebrovascular disease ( or , 1.70 ; 95% ci , 1.332.17 ) , and peripheral vascular disease ( or , 1.98 ; 95% ci , 1.322.82 ) when compared with controls .
indeed they also found psoriasis to be an independent risk factor for mortality ( or , 1.86 ; 95% ci , 1.562.21 ) as a result of the association with atherosclerosis .
these risk factors in combination with the chronic inflammatory process are thought to be significant components in the development of vascular disease [ 9 , 14 ] .
links with alterations in levels of folate and homocysteine in patients with psoriasis have also been implicated in contributing to the propagation of atherosclerosis and atherothrombotic events [ 9 , 15 , 16 ] .
  recent case control studies have demonstrated that patients with psoriasis have lower levels of folate in comparison to normal controls [ 9 , 15 , 17 , 18 ] .
postulated mechanisms include alterations in gut absorption of folate due to microscopic inflammatory changes seen in the bowel mucosa of patients with active psoriasis and psoriatic arthritis .
a more likely explanation however probably relates to the accelerated keratinocyte turnover seen in patients with psoriasis .
this action results in excessive consumption of folate used to methylate dna in these actively dividing cells thus lowering folate levels . conversely homocysteine levels are elevated in psoriasis patients [ 9 , 15 , 17 ] . in one case - controlled study this was found to directly correlate with disease severity and to be inversely related to plasma folate levels .
plasma homocysteine is an independent risk factor for cardiovascular disease [ 19 , 20 ] , peripheral vascular disease , cerebrovascular disease and possibly alzheimer 's diseases .
the magnitude of this risk is equivalent to the risk of smoking or dyslipidemia .
umol / l ) is thought to favour atherosclerosis and vascular thrombosis by a number of mechanisms .
these include damaging endothelial cells , promoting clot formation , decreasing flexibility of blood vessels leading to aortic stiffness , and reducing blood flow velocity .
the endothelial dysfunction is thought to result from the accumulation of asymmetrical dimethylarginine ( adma ) which is a natural inhibitor of nitric oxide synthase . as a result
there is a reduction in the production of the vasodilator nitric oxide which protects the vessel wall against the pathogenesis of atherosclerosis and thrombosis ( figure 1 ) .
it has been suggested that hyperhomocysteinemia in addition to other factors may be caused by reduced levels of folate in these patients [ 9 , 15 ] .
coenzymes methylene tetra - hydrofolate , methylcobalamin , and pyridoxal phosphate are essential for three of the enzymes involved in the metabolism of homocysteine and are dependent on folate , vitamin b12 and b6 , respectively . hence in patients with severe psoriasis who have large areas of rapid skin turnover and increased keratinocyte activity
this in turn results in reduced breakdown and elevated serum levels of homocysteine with all of its adverse effects .
  it appears from this paper that patients with psoriasis have lower levels of folate and higher levels of homocysteine than normal controls . as psoriasis
is associated with an increased risk of cardiovascular morbidity and mortality and homocysteine is an independent risk factor for cardiovascular disease , it may seem intuitive that managing this risk factor would have beneficial effects in terms of cardiovascular mortality and morbidity .
folate has long been used in combination with methotrexate in the management of psoriasis , psoriatic arthritis , and rheumatoid arthritis . here
it is effective in reducing gastrointestinal side effects and liver function test abnormalities . in a retrospective cohort study looking at over seven thousand patients with psoriasis , methotrexate
was found to reduce the incidence of vascular disease and this reduction was further enhanced when folic acid was added ( figure 2 ) .
however , homocysteine levels can be elevated for other reasons including obesity , hypertension , smoking , and excessive alcohol consumption all of which have significant prevalence in the psoriatic patient population .
armitage et al . in a double - blinded randomised control trial assessed the beneficial effects of lowering homocysteine levels in over 12,000 post - mi patients .
they failed to demonstrate any benefit in vascular outcomes from long - term reductions in homocysteine with folate and vitamin b12 supplementation .
it is possible that hyperhomocysteinemia in psoriasis is independent of folate deficiency and instead is linked with other risk factors such as hypertension and obesity .
 the psoriatic march  , a concept of how severe psoriasis may drive cardiovascular morbidity , suggests a process of genetic susceptibility triggered by environmental factors and immune responses .
it is this chronic inflammatory burden and state of insulin resistance which can result in endothelial dysfunction and ultimately atherosclerosis .
  it is well established that folic acid supplementation has a role in the treatment of psoriasis in conjunction with methotrexate treatment .
however , the evidence to support its use in reducing the risk of cardiovascular disease by directly impacting on plasma homocysteine levels is lacking .
now management of associated risk factors such as obesity , dyslipidemia , and hypertension as well as encouraging smoking cessation are paramount for these patients as is , of course , the management of their skin .

Answer:
psoriasis is a chronic inflammatory skin condition with an increased risk of cardiovascular disease .
 this risk has been attributed to an association with many independent risk factors including obesity , hypertension , smoking , and dyslipidemia .
 psoriasis patients also have lower levels of folate and conversely higher levels of homocysteine , which in itself is a risk factor for cardiovascular disease .
 it has been postulated that low folate levels in this group may be a direct cause of hyperhomocysteinemia and therefore a treatable risk factor by folate supplementation . this paper looks at the literature published to date on the relationship between psoriasis , homocysteine , and folate levels .


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:
salivary gland neoplasms constitute an important area in the field of pathology of head and neck region .
they are mainly classified as either hodgkin 's or non - hodgkin 's lymphoma ( nhl ) .
nhl comprises a heterogeneous group of lymphoid neoplasms with a spectrum of behaviour ranging from relatively indolent to highly aggressive and potentially fatal .
the vast majority of nhl represent b cell and less commonly t cell lineage neoplasm .
nhls of b cell origin are known to be relatively common in extra nodal sites and many are thought to originate from mucosa associated lymphoid tissue ( malt ) .
this is a low to intermediate grade lymphoma that show a follicular architecture and represents the neoplastic counterpart of germinal center b lymphocytes .
follicular lymphoma is very uncommon under the age - group of 40 years and is extremely rare in children .
the t ( 14;18 ) ( q32;q21 ) chromosome translocation has been purported to be the cytogenetic hallmark of follicular lymphoma .
the molecular consequence is deregulation of bcl2 expression leading to over expression of bcl2 proteins in neoplastic follicles .
a 40-year - old female patient reported to our institute with a complaint of swelling in the left side of lower jaw since 2 months [ figure 1 ] .
post its onset , the swelling gradually increased in size over a period of 2 months .
the patient is a known diabetic since 5 years and is under oral anti diabetic medication .
concurrent with the history of swelling , the patient gives a history of weight loss in past 2 months .
no history of cold , cough or fever . clinical picture showing the swelling in the left submandibular region examination revealed a swelling of 9  4 cm in size which extended anteriorly 1 cm in close proximity to chin on left side and posteriorly in line with the ear lobe [ figure 2 ] .
margins were well - defined and the swelling was firm , fixed to underlying tissues and non tender on palpation .
no local rise of temperature was seen in the concerned area . left submandibular lymph node was 0.5 cm in size and mildly tender on palpation .
few differential diagnoses such as sarcoidosis , sjogren 's syndrome , lymphomas and mikulicz disease were considered .
sjogren 's syndrome was ruled out as there was no history of dryness . in both sarcoidosis and sjogren 's syndrome
mikulicz disease is an autoimmune disease and thus was ruled out . swelling seen 2 cm below the ear lobe the following investigations were done :
 fnac gave an impression of chronic non specific lymphadenitis .
no evidence of cytological atypia seenultra sonography report showed a circumscribed mixed area of 3  1.5 cm in the anterior region of left submandibular gland .
no evidence of cytological atypia seen ultra sonography report showed a circumscribed mixed area of 3  1.5 cm in the anterior region of left submandibular gland .
the patient was further subjected to ct scan of head and neck and the impression was of
 submandibular salivary gland tumourmultiple submental and submandibular lymphadenopthy .

, a diagnosis of benign tumour of the left submandibular gland was given . during excision of the tumour , it was found that whole of the gland was involved .
so , total submandibular gland excision was done and the specimen was sent for histopathological analysis .
gross finding revealed a single bit of soft tissue measuring 4  6 2 cm , yellowish red in color , firm in consistency .
[ figure 3 ] cut sections revealed yellowish to whitish central core surrounded by whitish brown to brownish areas [ figure 4 ] .
specimen showing 2 lymph nodes attached to the soft tissue specimen grossed specimen showing yellowish to whitish central core surrounded by whitish brown to brownish areas histopathological examination revealed hematoxylin and eosin ( h and e ) stained sections revealed destruction of salivary gland architecture .
photomicrograph showing neoplastic lymphocytes in a follicular pattern.(h&e stain , 100 ) photomicrograph showing neoplastic lymphocytes with hyperchromatic nuclei and scanty cytoplasm .
( h&e stain , 200 ) based on the histopathological appearances , a provisional diagnosis of low grade lymphoma was made and immunohistochemical profiling was done to confirm the type of lymphoma . the tissue was stained for bcl2 an anti apoptotic marker , cd20 b lymphocyte marker , cd3 which is exclusively a t lymphocyte marker , cytokeratins and ema .
immunohistochemistry revealed that the cells were strongly positive for bcl-2 [ figure 7 ] and cd 20 [ figure 8 ] which are both cytoplasmic markers and negative for cd3 [ figure 9 ] .
( ihc stain , 200 ) photomicrograph showing neoplastic cells expressing strong positivity for cd20 .
( ihc stain , 100 ) photomicrograph showing neoplastic cells with negative expression for cd3 .
( ihc stain , 100 ) based on the results of immunohistochemical profiling , a diagnosis of follicular b cell lymphoma was reached .
patient was referred to higher center where full body mri did not reveal any foci of disease . nevertheless ,
considering the indolent course of this disease , she has been on regular follow up and has not reported with any clinically suspicious changes .
lymphomas also involve in the descending order of frequency , the submandibular gland ( 30% ) , minor salivary glands and the sub lingual glands .
the finding of a lymphoma in a major salivary gland could mean one of two things : either it is part of a disseminated process , or it is the first clinicopathologic evidence of lymphoma .
in the latter instance , whether the disease originated in the glandular stroma itself or in a para glandular lymph node and then invaded the stroma , the lymphoma is defined as primary , as long as there is no detectable disease outside the salivary gland .
hyman and wolf have given few criterions for diagnosis of primary lymphoma which are :
 involvement of gland should be the first clinical manifestation of the diseasehistologically , the disease should involve the gland parenchyma and not the adjacent node or soft tissue alonethere should be confirmation of malignant nature of lymphoid infiltrate .

involvement of gland should be the first clinical manifestation of the disease histologically , the disease should involve the gland parenchyma and not the adjacent node or soft tissue alone there should be confirmation of malignant nature of lymphoid infiltrate .
lichenfield et al . , reserved the diagnosis of primary salivary gland lymphoma , when lymphoma has been ruled out elsewhere in the body .
the diagnosis of lymphoma in case of a salivary gland swelling is rarely done preoperatively .
even though the diagnosis of lymphomas , in the algorithm of diagnosis of salivary gland swelling is rare , nevertheless , it should be considered .
follicular lymphoma , although unpredictable and often associated with a prolonged course shows indolent behavior .
overtime , there is a tendency to transform to a higher grade of lymphoma , usually diffuse large cell lymphoma . although various treatment modalities exist , none are curative and very few have been shown to prolong survival .

Answer:
lymphomas are neoplastic diseases of lymph nodes .
 lymphoma of the salivary gland is rare accounting for less than 5% of lymphomas overall .
 furthermore , lymphomas arising in the submandibular gland are reported to comprise 916% of all salivary gland lymphomas . among lymphomas originating from salivary glands ,
 the ratio of follicular lymphoma is very low .
 they can also be seen in the lymph nodes of the salivary glands which is an uncommon presentation . here ,
 we present a case follicular lymphoma which presented as a salivary gland tumour .


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:
malaria is one of the world 's leading killers , having a greater morbidity and mortality than any other infectious diseases , with greater mortality in children and pregnant women .
malaria is caused by a parasite of the genus plasmodium and transmitted by female anopheles mosquito .
renal damage and hemolysis induced by malaria , especially p. falciparum and p. vivax , occur between 2 and 6% of hospitalized patients with a mortality that can reach up to 50% .
the pathogenesis of renal damage and hemolysis during malaria infection is multifactorial and not well characterized , but several studies suggest involvement of cytoadherence of parasitized erythrocytes and proinflammatory response as well as oxidative stress [ 35 ] .
this has prompted research towards the discovery and development of new , safe , and affordable antihemolysis drugs during malaria infection . in this
plant extracts are commonly investigated in several parts of the world for their possible activities for using in malaria [ 710 ] . moreover , many studies recently endorsed the use of traditional medicinal plants to treat diseases [ 1116 ] .
this plant is widely found in asia and southeast asia including thailand and used for general weakness , malaria fevers , and chronic rheumatism .
this result is confirmed by the existence of phenolic and flavonoids such as catechin , luteolin , and borapetoside .
these are responsible for high antioxidant activity and other activities including anti - inflammation , antimicrobials , and anticancer [ 1921 ] .
the antioxidant properties of t. crispa stem extract make it useful for the treatment of diseases resulting from oxidative stress such as cardiovascular disease , cancer , liver damage , and renal disease .
it also has been used as an antimalarial agent in vivo [ 22 , 23 ] .
however , it has not been reported yet to use t. crispa stem extract to treat renal damage and hemolysis induced malaria infection .
hence , the present study was aimed to investigate the protective effects of t. crispa stem extract on renal damage and hemolysis induced by p. berghei infection in mice .
fresh stems of tinospora crispa were collected from natural environment in suphanburi province , thailand , from march to april 2015 .
stems were minced into small pieces and dried in hot - air oven at 60c for 72  h , after which the dried plants were ground and then extracted in distilled water at the proportion of 1  :  10  ( w / v ) using microwave at 360  w for 5  min .
the extract was filtered through whatman number 1 filter paper , and evaporation was then performed to remove solvent .
powder extract was dissolved in distilled water to obtain appropriate doses for using in mice and volume should not be higher than 1  ml .
drug doses , expressed in mg / kg of body weight , were adjusted at the time of administration according to the weight of the mice .
pathogen - free , female icr mice , aged 46 weeks and weighting 2530  g , were purchased from the national laboratory animal center , mahidol university , bangkok , thailand .
they were kept at 2225c with 12  h light / dark cycle and given standard mouse pellet and water ad libitum .
all procedures of the animal experiments were approved by the ethical committee on animal experimentation , faculty of medical technology , western university .

pbanka was kept alive by intraperitoneal ( ip ) passage of 1  10 parasitized erythrocytes in nave mice .
in addition , hematocrit ( % hct ) was also monitored by collecting tail vein into heparinized hematocrit tubes and centrifuged at 10,000  g for 10  min .
blood urea nitrogen ( bun ) and creatinine were used as indicators of renal function .
mouse blood was collected from tail vein into heparinized hematocrit tubes and centrifuged at 10,000  g for 10  min .
plasma was subsequently collected and used as subjects for measurement of bun and creatinine using an available commercial kit ( biosystems ) according to manufacturer 's instruction .
protective effect of aqueous crude extract of t. crispa on renal damage and hemolysis during malaria infection was done based on standard 4-day suppressive test .
groups of icr mice ( 5 mice of each ) were randomly divided , and infection was then performed with 1  10 parasitized erythrocytes of pbanka by ip injection .
two hours after infection , they were given orally by gavage with 500 , 1000 , and 2000  mg / kg of the extracts and every 24  h twice a day for 4 consecutive days .
three control groups were used ; normal controls were given either distilled water or the extract while untreated control was given only distilled water . on day 4 of experiment , tail blood was collected to assess hemolysis by measurement of % hct .
parasitemia was first detectable on day 1 after infection with a parasitemia of 0.5% and reached 65% on day 10 ( figure 1(a ) ) .
next , we observed that bun and creatinine levels were markedly increased in infected mice , and first significant ( p < 0.05 and p < 0.001 ) increases were found on day 4 after infection ( figures 1(b ) and 1(c ) ) .
additionally , we also observed progressive decreases of % hct in infected mice in response to the presence of parasitemia ( figure 1(d ) ) .
it was found that t. crispa stem extract showed protective effect on renal damage induced by pbanka infection in mice , and the highest activity was found at dose of 2000  mg / kg of extract treated group ( figure 2 ) .
the bun and creatinine levels were increased significantly ( p < 0.01 and p < 0.001 , resp . ) by malaria infection ( untreated group ) and infected mice treated with 500  mg / kg of the extract , compared to normal control .
interestingly , after oral administration of t. crispa stem extract , bun and creatinine levels declined significantly ( p < 0.01 and p < 0.001 , resp . ) , especially at doses of 1000 and 2000  mg / kg , compared to untreated control .
however , t. crispa stem extract could not be able to decrease parasitemia levels .

t. crispa stem extract exerted antihemolytic effect against pbanka infected mice . as shown in figure 3 ,
hemolysis was observed in untreated control and infected mice treated with 500  mg / kg of the extract as indicated by decreasing of % hct with significance ( p < 0.01 ) , compared to normal control .
interestingly , % hct was significantly ( p < 0.01 ) increased in infected mice treated with 1000 and 2000  mg / kg of the extract , compared to untreated control .
the highest effect was found at dose of 2000  mg / kg of the extract .
moreover , prolonged survival time of infected mice treated with this extract was also observed .
in the current study , we provide evidence that describes the protective effect of t. crispa stem extract on renal damage and hemolysis induced by p. berghei infection in mice .
the onset of renal damage and hemolysis in icr mice infected with pbanka come out from day 4 after infection and the incidence of renal damage and hemolysis were confirmed through manifestations such as increasing of bun and creatinine as well as decreasing of % hct in infected mice .
renal damage and hemolysis are proposed to be a consequence of parasite adhesion and exacerbated immune response against products of oxidative stress released during infection .
in addition , parasitized erythrocyte sequestration at the microvascular site of renal has also been discussed to induce renal damage .
the destruction of erythrocytes during blood stage infection accumulates high levels of toxic - free heme that has ability to induce oxidative stress from production of hydroxyl radicals via fenton / haber - weiss reaction .
moreover , heme - derived oxidative stress is considered to be a main factor in the iron - induced lipid peroxidation resulting in the formation of oxidized ldl .
therefore , these conditions derived by blood stage of infection result in renal damage and hemolysis .
however , protective effects of renal damage and hemolysis induced by malaria infection were found in infected mice treated with t. crispa stem extract .
polyphenols and flavonoids show high antioxidant and anti - inflammation properties and then protect oxidative stress development .
t. crispa stem extract has been shown to contain high amounts of polyphenols and flavonoids .
thus , the potent antioxidant activity of this extract might play a central role in protecting renal damage and hemolysis from oxidative stress induced by malaria infection .
moreover , t. crispa stem extract has been reported to have antimalarial activity against p. yoelii infection in mice .
so , antimalarial activity to inhibit p. berghei growth and subsequently inhibit renal damage and hemolysis might also be mentioned .
taken together , our results suggest that t. crispa stem extract shows protective effects against p. berghei - induced renal damage and hemolysis .
appropriate pharmaceutical strategies might now be devised to increase the low bioavailability of this extract and to protect against rapid in vivo metabolic transformation , in such a way to make them more amenable as alternative antimalarial drug in combination therapies .

Answer:
renal damage and hemolysis induced by malaria are associated with mortality in adult patients .
 it has been speculated that oxidative stress condition induced by malaria infection is involved in its pathology .
 thus , we aimed to investigate the protective effects of tinospora crispa stem extract on renal damage and hemolysis during plasmodium berghei infection
 . t. crispa stem extract was prepared using hot water method and used for oral treatment in mice .
 groups of icr mice were infected with 1  107 parasitized erythrocytes of p. berghei anka by intraperitoneal injection and given the extracts ( 500 , 1000 , and 2000  mg / kg ) twice a day for 4 consecutive days . to assess renal damage and hemolysis , blood urea nitrogen ( bun ) , creatinine , and hematocrit ( % hct ) levels
 were then evaluated , respectively .
 malaria infection resulted in renal damage and hemolysis as indicated by increasing of bun and creatinine and decreasing of % hct , respectively .
 however , protective effects on renal damage and hemolysis were observed in infected mice treated with these extracts at doses of 1000 and 2000  mg / kg . in conclusion ,
 t. crispa stem extract exerted protective effects on renal damage and hemolysis induced by malaria infection .
 this plant may work as potential source in the development of variety of herbal formulations for malarial treatment .


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:
sciatic hernias are one of the rarest types of hernia and often pose diagnostic difficulty to clinicians . imaging is often required to confirm the diagnosis and usually involves computed tomography ( ct ) or magnetic resonance imaging ( mri ) . to our knowledge , we report the 115th case of sciatic hernia in the literature who had a falsely negative ct but had the diagnosis confirmed using ultrasonography .
an 80-year - old lady was referred to the on - call surgical team by her gp with a 3-week history of a right - sided swelling of the buttock .
she had a past medical history of hypertension , osteoarthritis and pemphigus vulgaris and a past surgical history of a perianal abscess requiring incision and drainage .
she was allergic to penicillin and took regular oral betamethasone , xylometazoline nasal spray and topical aqueous cream .
she did not consume alcohol , was a non - smoker and lived in warden - controlled accommodation . on examination , her cardiac , respiratory and abdominal examinations were normal .
digital rectal examination revealed a non - tender stool - filled rectum with no palpable masses . on standing , a swelling on the medial aspect of the right buttock became apparent which was easily reducible , had audible bowel sounds and a positive cough impulse .
she was reviewed by the on - call consultant who discharged her with a working diagnosis of possible obturator hernia , with a plan for an outpatient ct of her pelvis and follow - up in clinic .
ct scan of the pelvis did not identify a cause for the swelling ( fig .  1 ) .
due to the positional nature of the swelling , a gluteal ultrasound was organized , which revealed a large colonic sciatic hernia ( fig .  2 ) .
as the patient had minimal symptoms and was not keen for surgical intervention , a plan for conservative management was agreed and the patient was discharged from clinic .

figure  1:ct of the patient 's pelvis demonstrating a normal right sciatic foramen ( arrowed ) .

us hip rt : confirms reducible herniation of colon in the right sciatic region into the buttock. ) ct of the patient 's pelvis demonstrating a normal right sciatic foramen ( arrowed ) .
hip rt : confirms reducible herniation of colon in the right sciatic region into the buttock. )
sciatic hernias are one of the rarest types of hernia and often pose diagnostic difficulty to the clinician .
a sciatic hernia is defined as herniation of intraperitoneal contents through either the greater or lesser sciatic foraminae ( fig .
the majority of sciatic hernias are found in women ( 77% ) with more than one - third of these being aged 60 or over .
the contents are variable and hernias containing ovaries , ureters , bladder , small and large intestine , omentum and dermoid cysts have been reported [ 16 ] .
half of patients report non - specific abdominal or pelvic pain and one third have a mass on clinical examination .
sciatica , intestinal obstruction , urinary sepsis and hydronephrosis have also been described [ 15 ] .
diagnostic laparoscopy or laparotomy is often required to fully evaluate the sac contents and to repair the defect [ 2 , 3 , 5 ] . in symptomatic patients ,
surgical repair is indicated due to the high risk of bowel strangulation [ 1 , 3 ] .

figure  3:pelvis demonstrating the greater ( red ) and lesser ( green ) sciatic foraminae .
diagnosis by clinical examination alone is possible in only the minority of cases and imaging is frequently used to confirm the suspicion of sciatic hernia .
commonly used imaging modalities are computerized tomography ( ct ) [ 25 ] and mri [ 3 , 4 ] , particularly if the sciatic nerve is thought to be involved .
currently , the most commonly used imaging modality of choice is a ct scan with the patient supine . however ,
if the hernia is only apparent in a dependent position , this can produce a false - negative result , as in our case .
the benefit of ultrasound is that it allows for real - time positional assessment of the region of interest , to reduce the risk of missing this rare but significant hernia .
due to their rarity , sciatic hernias are often not considered in the differential diagnosis .
the authors recommend that all patients presenting with non - specific abdominal or pelvic pain associated with a gluteal swelling should have sciatic hernia considered amongst their differential diagnosis . for patients
in which there is a high degree of clinical suspicion for a sciatic hernia and a negative ct , the use of ultrasonography for positional defects may be a useful aid to confirming the suspected diagnosis .

Answer:
sciatic hernias are one of the rarest types of hernia and often pose diagnostic difficulty to clinicians . we report a case of an 80-year - old lady with a sciatic hernia who had a falsely negative computed tomography ( ct ) but was found to have a colonic hernia on ultrasonography .
 the authors recommend that for patients in which there is a high degree of clinical suspicion for a sciatic hernia and a negative ct , ultrasonography may be considered as a useful imaging modality to confirm the diagnosis .


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:
in a recent issue of critical care , we presented a series of 13 patients undergoing post - cardiotomy extracorporeal membrane oxygenation ( ecmo ) with bivalirudin - based anticoagulation .
after this series , we satisfactorily continued this experience , reaching about 20 patients treated .
however , we think that a word of caution should be added to our recently published experience . owing to its pharmacological profile
, bivalirudin is rapidly cleaved by proteolytic enzymes , and its half - life is about 25 minutes when the renal function is normal .
the use of bivalirudin for cardiopulmonary bypass ( cpb )   and ecmo   is a feasible option .
however , it is recommended that , during cpb , blood stagnation in the circuit be avoided because the rapid cleavage of bivalirudin may result in thrombosis .
the ecmo circuit is devoid of a reservoir , and therefore blood stagnation is usually not a circuit- related problem .
conversely , under some circumstances , the cardiac chambers may act as a ' natural reservoir ' , which entails blood stagnation and the risk for spontaneous intracardiac thrombosis .
this is particularly true in the case of a very large right or left atrium with insufficient venous drainage or the case of very poor ventricular systolic function with intraventricular blood stagnation . to avoid this condition
, we think that maintaining a partial ecmo support , leaving a minimal degree of intracardiac blood flow , may be a reasonable choice .
this may be checked by echocardiographic view of heart valve movement or simply by the observation of some degree of pulsatile arterial blood pressure .
we think that , in the event of echocardiographic evidence of a ' smoke effect ' within one or more cardiac chambers , bivalirudin should be replaced by standard heparin anticoagulation .
intracardiac thrombus formation during ecmo with heparin anticoagulation has been described as well , but the pharmacokinetic properties of heparin may limit the risk of thrombus formation due to blood stagnation .

Answer:
bivalirudin has been proposed as the sole anticoagulant in patients under extracorporeal membrane oxygenation ( ecmo ) or cardiopulmonary bypass .
 owing to the pharmacodynamic properties of bivalirudin , areas of blood stagnation should be carefully avoided in order to limit the risk of thrombosis .
 the ecmo circuit has no reservoir and is usually devoid of blood stagnation areas .
 conversely , under some circumstances , intracardiac blood stagnation areas may exist . in this case
 , there is a potential risk for the spontaneous formation of an intracardiac thrombus .
 we suggest that , under bivalirudin anticoagulation , a minimal degree of intracardiac blood flow with left heart valve movement is allowed .


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 use of bleaching materials both hydrogen peroxide and carbamide peroxide has become an attractive procedure in the dental clinic .
furthermore , the use of fluoride - releasing glass ionomer as a dental restorative material has also become popular .
the situation where these materials interact within the oral cavity during the bleaching process can occur frequently ; thus , understanding their reaction is important .
the bleaching process is believed to occur through oxidation by hydroxyl radicals that are generated from the bleaching agent . with clinically favorable and safe aspects for patients ,
several studies have shown the effectiveness of bleaching agents on dental restorative materials and teeth with regard to surface hardness , or other modifications . during setting of glass ionomer ,
fluoride ions are produced from strong soluble aluminofluoride complexes like alf . when a fully set glass ionomer is exposed to neutral aqueous solutions , it absorbs water and releases ions such as sodium , silica , calcium , and fluoride .
two processes occur during fluoride release : a fast elution process during the early periods , and a long - term diffusive process .
it is also influenced by experimental factors , i.e. , storage media , frequency of change of the storage solution , composition and ph - value of saliva , plaque , and pellicle formation . in vitro ,
fluoride release increases in acidic media ; this was explained by the fact that decreasing ph increases the dissolution of the material leading to a higher fluoride level in acidic immersion .
thereby , the proportion of free fluoride to bound fluoride was higher under acidic than under neutral conditions . when hydrogen peroxide is stored , an acidic ph must be maintained to extend the shelf life .
they found that at home bleaching products have a ph range from 5.66 to 7.3 .
while they found ph of in - office bleaching system were lower and ranged from 3.6 to 6.5 .
when hydrogen peroxide interacts with dental materials , it decomposes to form hydroxyl radical intermediates and finally to form water and oxygen . also , carbamide peroxide will dissociate to h2o2 , co2 , urea and nh3 , and then h2o2 will decompose again to water and oxygen finally . those chemical ingredients may affect the fluoride release of glass ionomer restoratives .
the purpose of this study was to evaluate the effect of vital bleaching on the fluoride release of various types of glass ionomer restorations . also , to compare the fluoride release of various types of glass ionomer restorations .
two vital bleaching commercial products and three types of glass ionomer restorative materials were selected for this study .
bleaching materials used were opalescence xtra boost ( 38%hydrogen peroxide with ph of 7 ) and opalescence quick ( 35%carbamide peroxide with ph of 6 ) both manufactured by ultradent ( inc .
glass ionomer materials used were ketac fil ( conventional glass ionomer ) , photac fil ( resin modified glass ionomer ) , and f2000 ( poly acid modified composite resin ) manufactured by 3 m ( espe , st paul , usa ) .
thirty disk shaped specimens ( 5 mm in diameter and 2 mm in thickness ) were prepared for each brand of glass ionomer .
the mold was sandwiched between two glass plates to allow setting of glass ionomer under pressure .
capsules of ketac fil were activated then triturated according to manufacturer instructions for 15 s , injected in the holes of the mold in one increment .
the mold was filled to slight excess , the specimen 's top surface was covered by a mylar strip and a glass slide was secured to flatten the surface and pressed with standard load 500 mg over the mold then left for setting .
capsules of both photac fil and f2000 were triturated according to manufacturer instructions for 15 s and injected into holes , covered with glass slide , and light cured for 40 s per each side using a light source ( pencure , j morita mfg corp . ,
each disk specimen was removed from the mold by separating its two halves and placed in a numerated plastic tube containing 5 ml of distilled water , tightly sealed with a cap .
the specimens were incubated at 37c during the whole experimental period ( 3 months ) . after 24 h
each group was further subdivided into three sub - groups , 10 samples for each group .
the first sub group was a control group , the second sub group was bleached with opalescence xtra ( ox ) , and the last one was bleached with opalescence quick ( oq ) .
second and third subgroups were bleached with the two bleaching agents ox and oq according to their manufacturer instructions , every sample was covered with 2 ml of the bleaching material and left for 1 h. disks were then washed thoroughly with distilled water , and then returned back to their tubes . control samples ( the first sub group ) returned back to the tubes after water in the tubes of all subgroups being changed with new 5 ml of distilled water .
the measurements were performed after 1 week , 1 month , and 3 months and every time , samples were rinsed with distilled water and water in the tubes changed with new 5 ml of distilled water .
fluoride release measurements were performed using specific ion electrode ( ph meter f-22  horiba  ) after adding total ionic strength adjustment buffer ( tisab ) solution .
data were recorded and analyzed by using one - way analysis of variance ( anova ) followed by bonferroni multiple comparison post hoc test at the significance level of  = 0.05 .
the analysis of variance was carried out considering the factors ( material , time , and interaction ) .
data were recorded and analyzed by using one - way analysis of variance ( anova ) followed by bonferroni multiple comparison post hoc test at the significance level of  = 0.05 .
the analysis of variance was carried out considering the factors ( material , time , and interaction ) .
time had highly significant effect on fluoride released from all glass ionomer materials under test at p < 0.05 [ table 1 ] . ketac fil showed initial burst in fluoride release in the first week ( t1 ) of 58.6 ppm , then concentration of fluoride decreased sharply after 1 month ( t2 ) of 10.94 ppm .
after 3 months ( t3 ) , the concentration of fluoride decreased again of 5.94 ppm [ figure 1 ] .
for photac fil , time had only a significant effect on fluoride release [ figure 2 ] .
fluoride release of f2000 was also affected by time and this was highly significant [ figure 3 ] .
effect of time on fluoride release for three types of glass ionomer materials mean fluoride concentration of ketac fil as affected by time .
studying fluoride release as affected by the type of glass ionomer material regardless the type of bleaching and time ; the result was highly significant at p < 0.01 . comparing the three brands ;
there was no significant difference at p > 0.05 in fluoride release considering only the type of bleaching regardless type of glass ionomer and time .
a significant increase in the mean fluoride released from ketac fil bleached with opalescence xtra compared to the untreated control group and the group bleached with opalescence quick . for photac fil ,
opalescence xtra caused slight increase in fluoride release while no significant differences in fluoride release were found after bleaching f2000 .
according to the type of bleaching and the time , highly significant difference was found between the tested materials at p < 0.01 .
the use of hydrogen peroxide or peroxide releasing agents , such as carbamide peroxide or sodium perborate for brightening discolored teeth has become a popular treatment modality .
glass ionomers are often used for restoration of cervical lesions because of bonding to tooth structure and releasing fluoride .
the influence of various bleaching agents on physical properties , surface morphology , and color of different restorative materials has been investigated in several in vitro studies simulating the clinical situation as closely as possible . in our study
, it was found that the effect of bleaching on fluoride release of glass ionomer is material dependent depends on the type of bleaching material and the type of glass ionomer .
moreover , time factor was found to have an essential role . the high initial fluoride
effect was only observed with ketac fil and photac fil after 1 week and dropped sharply by the second period after 1 month .
this finding is in agreement with previous studies which may be attributed to the high instability and erosion of glass ionomer during the early setting period .
those studies have shown that the cumulative amount of fluoride ions released from glass ionomer cements , after a short period of time , is diffusion controlled and follows a decreasing gradient , which is linear to the square root of time .
thereby , the initial high amounts of fluoride rapidly decrease after 24 - 72 h and plateaued to a nearly constant level within 10 - 20 days . in contrast
significant difference in fluoride release was found between both ketac fil , photac fil , and f2000 but no significant difference was found between ketac fil and photac fil .
ranking the three brands according to their fluoride release at the first period of the test ; ketac fill was the material with the greatest rate of fluoride release , followed by photac fill then f2000 .
this difference can be explained by the composition of the compomer brands , which exhibited higher fluoride content and contained smaller fillers , which might lead to a better reactivity due to the greater size of the specific surface .
however , it was material dependent and depended on the type of bleaching , type of glass ionomer , and time .
this effect was highly significant by the first week and did not prolong to other periods of the test .
, 1997 who stated that the main daily release of fluoride did not differ significantly between bleaching agent and control .
the reason for the contrasting results between the two studies may be attributed to different concentrations of bleaching agents used in both studies .
opalescence quick has no significant effect on the fluoride release of the three materials . excluding the ph factor ( as both bleaching materials are close to neutral ) , this can be attributed to that : carbamide peroxide degrades into approximately one - third hydrogen peroxide and two - thirds urea , and hydrogen peroxide can be considered its active ingredient .
the hydrogen peroxide content in opalescence quick is therefore much lower than that in opalescence xtra .
also opalescence quick has more complicated steps of break down to free radicals than opalescence xtra .
this result was in agreement with lee , et al . , 2002 who concluded that hydrogen peroxide has a similar effect on the fluoride release from compomers compared to the case of distilled water .
opalescence xtra ( ox ) increased fluoride release from conventional and resin - modified glass ionomers in the first week while the effect faded by time .
opalescence quick ( oq ) had no significant effect on the fluoride release of the three materials .

Answer:
objective : this study was designed to evaluate the effect of two bleaching agents on the fluoride release of three types of glass ionomer materials.materials and methods : a total of 90 specimens of the tested materials ( ketac fil , photac fil and f2000 ) were prepared by a split teflon ring with an internal diameter of 5 mm and thickness of 2 mm .
 the tested materials were applied and bleached according to manufacturer instructions .
 fluoride release measurements were made by using specific ion electrode.results:results revealed that bleaching with opalescence xtra caused little increase in fluoride release from ketac fil and photac fil but has no effect on f2000 .
 however , opalescence quick had no significant effect on the three tested materials.conclusions:bleaching effect on fluoride release is material dependent and time has a significant role on fluoride release .


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:
early atherogenesis is characterized by the recruitment of circulating leukocytes ( e.g. , monocytes / macrophages and t - lymphocytes etc . ) into artery wall , the formation of foam cells in the vessel intima , leading to the development of atherosclerotic lesions .
the inflammatory responses in the atherosclerotic lesions play a crucial role to promote plaque rupture and thrombosis in the late progression of atherosclerosis , leading to myocardial infarction and strokes ( libby , 2002 ) .
the rupture - prone plaque is featured by a large lipid core and accumulation of inflammatory cells including macrophages and t - lymphocytes ( mann & davies , 1996 ) . a family of matrix metalloproteinases ( mmps ) , which are proteolytic enzymes secreted by the inflammatory cells , play a pivotal role in degrading extracellular matrix and plaque rupturing ( newby , 2005 ) .
chemokines , a superfamily of chemotactic cytokines , not only cause the recruitment of leukocytes into the arterial wall , but also influence atherosclerotic plaque stability by enhancing mmps releases ( reape & groot , 1999 ; sheikine & hansson , 2004 ) , and thus play a crucial role in both the initiation and the progression of atherosclerosis .
leukotactin-1 ( lkn-1/ccl15 ) , a new member of the human cc chemokine family , is a potent chemoattractant for leukocytes , and it is implicated in inflammatory pathologies including atherosclerosis . our previous study and
others have shown that the levels of lkn-1/ccl15 expression are markedly up - regulated in macrophage - derived foam cells and in human atherosclerotic lesions ( lee et al . , 2002 ; yu et al . , 2004 ) , and moreover , the proatherogenic mediators such as oxidized lipoprotein and oxidative stress markedly upregulte lkn-1/ccl15 gene expression and protein release from the foam cells ( yu et al . , 2004 ) , indicating lkn-1/ccl15 plays a role in the initiation of atherogenesis .
however , it remains unclear whether lkn-1/ccl15 is associated with the progression of atherosclerosis . in the present study
, we investigated whether lkn-1/ccl15 can enhance mmp-9 release from macrophages and/or foam cells , which influence plaque rupture .
our data demonstrated that lkn-1/ccl15 enhanced mmp-9 protein release from human macrophages and macrophage - derived foam cells , indicating that lkn-1/ccl15 may be associated with the vulnerability of plaque rupture in the late stage of atherosclerosis .
the cells were plated at a density of 5  10 cells / ml in the medium containing phorbol myristate acetate ( pma , sigma ) at 10 m for 48 h to induce their differentiation into macrophages .
after washings twice with hbss without ca and mg , the pbmcs were then suspended in 10% fbs containing rpmi and incubated for 60 min at 37 to let the monocytes attach to the culture dish .
the attached monocytes were harvested by vigorous pipetting and plated at a density of 5  10 cells / ml in the medium containing pma at 10 m for 48 h to induce their differentiation into macrophages .
human low density lipoprotein ( ldl ) ( d = 1.006 - 1.063 ) was separated from freshly drawn normal plasma sample by sequential ultracentrifugation and extensively dialyzed at 4 against 0.15 mol / l nacl and 0.01% edta .
after edta was removed , ldl was subjected to oxidative modification by incubation with cu ( 5 m cuso4 , 16 h at 37 ) .
then cu was removed by extensive dialysis ( yu et al . , 2004 ) .
the extent of modification was assessed by the determination of electrophoretic mobility on agarose gels . in agarose gel electrophoresis ,
oxldl was stored at 4 and was used within 4 weeks of preparation . to prepare macrophage - derived foam cells ,
human thp-1 cells were plated at a density of 5  10 cells / ml in the medium containing pma at 10 m for 48 h to induce their differentiation into macrophages , and then the cells were treated with human oxidized ldl ( 25 g / ml ) for 4 days ( yu et al . , 2004 ) .
the gelatinolytic activities of mmp-9 in the conditioning culture medium were assayed by electrophoresis on 10% polyacrylamide gels containing 1 mg / ml gelatin at 4. page gels were run at 120 v , washed in 2.5% triton x-100 for 1 h , and then incubated for 16 h at 37 in activation buffer ( 50 mm tris - hcl , ph 7.5 , 10 mm cacl2 ) . after staining with coomassie blue ( 10% glacial acetic acid , 30% methanol and 1.5% coomassie brilliant blue ) for 2 - 3 h , the gel was destained with a solution of 10% glacial acetic acid , and 30% methanol without coomassie blue for 1 h. white lysis zones indicating gelatin degradation were revealed by staining with coomassie brilliant blue r-250 .
the cells were plated at a density of 5  10 cells / ml in the medium containing phorbol myristate acetate ( pma , sigma ) at 10 m for 48 h to induce their differentiation into macrophages .
after washings twice with hbss without ca and mg , the pbmcs were then suspended in 10% fbs containing rpmi and incubated for 60 min at 37 to let the monocytes attach to the culture dish .
the attached monocytes were harvested by vigorous pipetting and plated at a density of 5  10 cells / ml in the medium containing pma at 10 m for 48 h to induce their differentiation into macrophages .
human low density lipoprotein ( ldl ) ( d = 1.006 - 1.063 ) was separated from freshly drawn normal plasma sample by sequential ultracentrifugation and extensively dialyzed at 4 against 0.15 mol / l nacl and 0.01% edta .
after edta was removed , ldl was subjected to oxidative modification by incubation with cu ( 5 m cuso4 , 16 h at 37 ) .
then cu was removed by extensive dialysis ( yu et al . , 2004 ) .
the extent of modification was assessed by the determination of electrophoretic mobility on agarose gels . in agarose gel electrophoresis ,
to prepare macrophage - derived foam cells , human thp-1 cells were plated at a density of 5  10 cells / ml in the medium containing pma at 10 m for 48 h to induce their differentiation into macrophages , and then the cells were treated with human oxidized ldl ( 25 g / ml ) for 4 days ( yu et al . , 2004 ) .
the gelatinolytic activities of mmp-9 in the conditioning culture medium were assayed by electrophoresis on 10% polyacrylamide gels containing 1 mg / ml gelatin at 4. page gels were run at 120 v , washed in 2.5% triton x-100 for 1 h , and then incubated for 16 h at 37 in activation buffer ( 50 mm tris - hcl , ph 7.5 , 10 mm cacl2 ) . after staining with coomassie blue ( 10% glacial acetic acid , 30% methanol and 1.5% coomassie brilliant blue ) for 2 - 3 h , the gel was destained with a solution of 10% glacial acetic acid , and 30% methanol without coomassie blue for 1 h. white lysis zones indicating gelatin degradation were revealed by staining with coomassie brilliant blue r-250 .
the present study has demonstrated that lkn-1/ccl15 enhances mmp-9 protein release by macrophages and macrophages - derived foam cells , indicating that lkn-1/ccl15 may play a role in the plaque rupture of the atherosclerotic lesions .
macrophages , which are abundant in ruptured atherosclerotic plaques , express multiple mmps , weakening the plaque and making it rupture prone ( boyle , 2005 ) . among mmps , mmp-9 ( 92-kda gelatinase b ) , which is a prevalent form expressed by activated macrophages and foam cells , is found in human coronary atherosclerotic lesions ( galis & khatri , 2002 ; pasterkamp et al . , 2000 ) .
we found that lkn-1 significantly activated human thp-1 monocytes - derived macrophages and human pbmc - derived macrophages to release mmp-9 ( fig . 1a and 1b ) .
it has been shown that the circulating levels of lkn-1 are increased in plasma of atherosclerotic patients , and lkn-1 stimulates endothelial cells to release intracellular adhesion molecule-1 ( yu et al . ,
2004 ) . since mmp-9 is required for monocyte infiltration through endothelium from blood , lkn1/ccl15 action on macrophages to release mmp-9 may accelerate the recruitment of macrophages into the atherosclerotic lesions .
it has been shown that the expression levels of chemokine genes such as monocyte chemoattractant protein-1 ( mcp-1 ) and interleukin-8 ( il-8 ) are upregulated in human atherosclerotic lesions and they are associated with plaque rupture by activating endothelial cells and smooth muscle cells to release mmps ( kodali et al .
atherosclerotic lesions consist of mainly macrophages and lipid - laden foam cells , and thus excessive production of mmp-9 by lkn-1/ccl15 from macrophages and macrophage - derived foam cells in the lesions may accelerate the destabilization and rupture of the fibrous cap of the atherosclerotic plaque .
our data demonstrated that lkn-1 markedly enhanced the production of mmp-9 from macrophage - derived foam cells ( fig .
we have previously shown that proatherogenic mediators enhance lkn-1/ccl15 release from macrophages and macrophage - derived foam cells ( yu et al . , 2004 ) .
therefore , it can be postulated that macrophages and macrophage - derived foam cells in atherosclerotic lesions may enhance the local concentration of lkn-1 in the lesions , and lkn-1/ccl15 subsequently stimulate the macrophages / foam cells per se to secrete mmp-9 , indicating that lkn-1/ccl15 action on macrophages and foam cells to release mmp-9 may contribute to plaque destabilization in the progression of atherosclerosis . in conclusion , lkn-1/ccl15 enhanced mmp-9 protein secretion from thp-1 monocytic cells - derived macrophages , human pbmc - derived macrophages , and thp-1 macrophage - derived foam cells in a dose dependent manner . considering the association of mmp-9 in plaque rupture , our findings suggest that lkn-1/ccl15 could be associated with plaque destabilization in the progression of atherosclerosis . lkn-1/ccl15 may be a useful target for the management of atherosclerosis .
further studies are needed to elucidate the inhibitory effect of phytochemicals or food factors on lkn-1/ccl15 release from macrophages / foam cells .

Answer:
atherosclerosis is characterized by a chronic inflammatory disease , and chemokines play an important role in both initiation and progression of atherosclerosis development .
 leukotactin-1 ( lkn-1/ccl15 ) , a new member of the human cc chemokine family , is a potent chemoattractant for leukocytes .
 our previous study has demonstrated that lkn-1/ccl15 plays a role in the initiation of atherosclerosis , however , little is currently known whether lkn-1/ccl15 is associated with the progression of atherosclerosis .
 matrix metalloproteinases ( mmps ) in human coronary atherosclerotic lesions play a crucial role in the progression of atherosclerosis by altering the vulnerability of plaque rupture . in the present study
 , we examined whether lkn-1/ccl15 modulates mmp-9 release , which is a prevalent form expressed by activated macrophages and foam cells . human thp-1 monocytic cells and/or human peripheral blood monocytes ( pbmc ) were treated with phorbol myristate acetate to induce their differentiation into macrophages .
 foam cells were prepared by the treatment of thp-1 macrophages with human oxidized ldl .
 the macrophages and foam cells were treated with lkn-1/ccl15 , and the levels of mmp-9 release were measured by gelatin zymography . lkn-1/ccl15
 significantly enhanced the levels of mmp-9 protein secretion from thp-1 monocytic cells - derived macrophages , human pbmc - derived macrophages , as well as macrophage - derived foam cell in a dose dependent manner .
 our data suggest that the action of lkn-1/ccl15 on macrophages and foam cells to release mmp-9 may contribute to plaque destabilization in the progression of atherosclerosis .


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:
worksites in glass and metal works , foundries , rolling mills , in the vicinity of hardening furnaces , rotary kilns in the cement industry , high - temperature laboratory furnaces , as well as firefighting , are associated , in addition to common mechanical hazards ( e.g. , due to splashes of molten metals and slag ) , sparks and direct contact with open fires , with hazards caused by emission of harmful optic radiation within the visible ( vis ) and infrared ( ir ) spectrum range .
excessive exposure to ir radiation leads to dryness of the mucous membranes , burns of the eyeball and development of cataracts .
protection against thermal hazards due to excessive amounts of ir radiation reaching the eyes is provided by protective optic filters installed in spectacles , goggles or face protections . besides protecting the user against hazardous ir radiation
, such filters should ensure that the object / area of work can be seen clearly . if the level of ir radiation is very high ,
the use of filters reflecting radiation is recommended , as it allows the temperature increase in the filter itself to be reduced .
the filters currently used for the protection of the face and eyes against hazardous ir radiation are of metallic reflective type , made of glass or organic material ( mainly polycarbonate ) bases coated with a single metallic layer for reflectance of ir radiation or absorption filters .
absorption filters are manufactured from dyed glass obtained in a mass staining process by introduction of a factor modifying the radiation within the vis and near infrared ( nir ) spectrum range passing through the filter .
the effect of a protective optical filter obtained as a result of this process is based on absorption of a large proportion of optic radiation , whereas only a small proportion of radiation the filter is exposed to is reflected .
this is an undesirable phenomenon , contributing to deterioration of the filter user 's comfort .
reflective metallic filters are obtained by deposition of a metallic layer of copper ( cu ) or gold ( au ) on mineral or organic bases .
such filters take advantage of the characteristic properties of the metals used in their production , i.e. , significant reflection coefficient for ir radiation and significant transmittance for the vis spectrum . despite the fact that the technique of deposition of interference layers has been known for many years   the application of thin film ir filters in eye protections to block
the previous papers published by the authors of this study   contain descriptions of the structure of interference filters designed for application in eye protections
highly effective in reduction of ir radiation with high level of transmission of the vis spectrum .
the authors investigated also the optical and mechanical parameters of the newly developed protective optic filters manufactured with the use of interference technologies .
the analysis of the results of the conducted tests demonstrated numerous advantages of interference technology application in the construction of protective filters , including : improved resistance to damage of the external protective filter surface ( cracking , scratching etc . ) as well as high reflection coefficients for the nir spectrum .
the aim of the present study was to compare the optic properties of protective filters manufactured by taking advantage of the interference technology and those coated with a single metallic layer reflecting ir radiation .
the coefficients characterizing their optic parameters , allowing to assess the protective properties within the vis and ir spectrum range were compared .
the following coefficients were analysed :
 luminous transmittance (
 v),ir transmittance within the 7801400  nm range (
 a),ir transmittance within the 7802000  nm range (
 n),ir reflectance within the 7802000  nm range ( r
 n),ir absorptance within the 7802000  nm range ( a
 n),shade number ( n ) .

luminous transmittance (
 v ) , ir transmittance within the 7801400  nm range (
 a ) , ir transmittance within the 7802000  nm range (
 n ) , ir reflectance within the 7802000  nm range ( r
 n ) , ir absorptance within the 7802000  nm range ( a
 n ) , the level of protection ( shade number ) is determined on the basis of luminous transmittance ( the higher protection level correlates with the higher level of ir radiation blocked and appropriately lower vis light transmittance ) .
protection level consists of a code number ( e.g. , 4 ) for ir filters and a shade number ( e.g. , 3 , 5 , 7 ) calculated according to the following equation :
 ( 1 )
 where
 v
 =  luminous transmittance . for the particular level of protection , the mean ir transmittance within the 7801400 and 7802000  nm ranges as well as the ir reflectance and absorptance within the 7802000  nm range are determined .
for comparative analysis of the metallic reflective filters available in the market versus the interference filters developed by the authors , the following samples were prepared for the tests :
 off the shelf metallic reflective filters on a polycarbonate base ( flat parallel plate of 50  mm diameter and 2  mm thickness with a metallic layer of copper ( cu )  protection levels : 4 - 3 , 4 - 5 , 4 - 7);interference filters on a polycarbonate base ( flat parallel plate of 50  mm diameter with interference coating made up of the following materials : aluminium , h4  latio3 substance and silicon dioxide ) .
  off the shelf metallic reflective filters on a polycarbonate base ( flat parallel plate of 50  mm diameter and 2  mm thickness with a metallic layer of copper ( cu )  protection levels : 4 - 3 , 4 - 5 , 4 - 7 ) ; interference filters on a polycarbonate base ( flat parallel plate of 50  mm diameter with interference coating made up of the following materials : aluminium , h4  latio3 substance and silicon dioxide ) .
the protection levels , luminous transmittance and symbols used for marking the tested filters are presented in table 1 .

characteristics of the filters.symbolluminous transmittance v ( % ) protection levelfilter typecu 4 - 314.1334 - 3metallic reflectiveitf 4 - 39.0824 - 3interferencecu 4 - 52.0214 - 5metallic reflectiveitf 4 - 51.4704 - 5interferencecu 4 - 70.3534 - 7metallic reflectiveitf
4 - 70.1604 - 7interferencenote : protection level consists of code number ( 4 ) for infrared filters and shade number ( 3 , 5 , 7 ) calculated according to equation ( 1 ) .

note : protection level consists of code number ( 4 ) for infrared filters and shade number ( 3 , 5 , 7 ) calculated according to equation ( 1 ) .
optical properties of the filters were measured with a cary 5000 spectrophotometer ( varian , australia ) . the spectrophotometer enabled transmittance or reflectance of optical radiation within the vis and nir spectrum to be recorded with 1  nm steps and 0.001% resolution level .
spectral transmittance and reflectance measurements were carried out within the wavelength range of 7802000  nm .
the quartz halogen lamp was used as a source of radiation . to detect transmitted or reflected radiation
the photomultiplier tube and lead sulphide detector were used for vis and nir spectrum , respectively .
spectral transmittance was measured with incident radiation falling normally on the filter surface in the visual centre ( defined as in ) . for spectral reflectance
the measurements were taken every second owing to the high absorption of investigated filters within the nir region .
since the minimum averaging time of the cary 5000 spectrophotometer was 0.0125  s , the values of transmittance or reflectance were measured 125 times for a given wavelength .
the aforementioned coefficients were calculated from the following equations [ 1012 ] :
 luminous transmittance
 ( 2 )

 where ( )  =  spectral transmittance , v( )  =  spectral visibility function of the average human eye for daylight or night vision , s
 d65( )  =  spectral energy distribution of standard illuminant d65 ;
 ir transmittance within the 7801400  nm range
 ( 3 )

 where ( )  =  spectral transmittance ;
 ir transmittance within the 7802000  nm range
 ( 4 )

 where ( )  =  spectral transmittance ;
 ir reflectance within the 7802000  nm range
 ( 5 )

 where ( )  =  spectral reflectance ;
 ir absorptance within the 7802000  nm range
 ( 6 )

 where r
 n  =  ir reflectance within the 7802000  nm range ,
 n  =  ir transmittance within the 7802000  nm range .
luminous transmittance
 ( 2 )
  ir transmittance within the 7801400  nm range
 ( 3 )
  ir transmittance within the 7802000  nm range
 ( 4 )
  ir reflectance within the 7802000  nm range
 ( 5 )
  ir absorptance within the 7802000  nm range
 ( 6 )
  the factor before integrals corresponding to the value of the measurement step at the measurement of spectral characteristics .
transmittance and reflectance characteristics of the studied filters.note : cu 4 - 3  =  metallic reflective filter ; itf 4 - 3  =  interference filter ; cu 4 - 5  =  metallic reflective filter ; itf 4 - 5  =  interference filter ; cu 4 - 7  =  metallic reflective filter ; itf 4 - 7  =  interference filter .

table 2 presents the values of coefficients determined on the basis of equations ( 3)(6 ) .

infrared transmittance within the 7801400 and 7802000  nm range , infrared reflectance within the 7802000  nm range and infrared absorptance within the 7802000  nm range .
infrared transmittance a and n ( % ) infrared reflectance rn ( % ) infrared absorptance an ( % ) symbola 7801400 ( nm)n 7802000 ( nm)rn 7802000 ( nm)an 7802000 ( nm)cu 4 - 31.4860.94283.51615.542itf 4 - 31.0030.56382.08417.353cu 4 - 50.2160.13487.31912.547itf 4 - 50.0380.00691.0378.957cu 4 - 70.0040.02388.30811.669itf 4 - 70.0040.03994.3125.649

optical radiation within the 7801400  nm spectrum range passes through the anterior compartment of the eye , the lens and reaches the retina . exposure to an excessive amount of radiation from this range
can result in burns of the retina and , in extreme cases , its permanent damage .
, chronic long - term exposure may lead to the development of cataracts , referred to as ir or glass worker 's cataracts . in view of the above
the results presented on the graphs in figure 1 and the determined transmittance values ( see table 2 ) indicate unequivocally more effective blocking of ir radiation provided by interference filters .
the values of
 a and
 n for interference filters are lower even by an order of magnitude than those obtained for the metallic reflective filters .
for instance , the mean value of ir transmittance within the 7802000  nm range for interference filters with protection level 4 - 5 ( one of the most common protection levels used in the metallurgic industry ) equals 0.006% and is significantly lower than the maximum acceptable value specified in , which is 10.6% .
for all the investigated filters , the values of r
 n exceed 60% , which classifies them in the group of filters with increased ir reflectance .
the levels of the ir absorptance for metallic reflective filters and interference filters of 4 - 3 and 4 - 5 protection class are similar . for the highest of the investigated protection levels  4 - 7
the above findings are important for selection of a filter appropriate for the radiation source .
the selection of filter protection level is dependent on the temperature of the radiation source .
the 4 - 7 level is used for radiation sources whose temperature exceeds 1600  k ( e.g. , occurs in the metallurgical industry ) . with such high temperatures ,
reduction of filter heating as a result of exposure to ir radiation is important . as it follows from comparative analysis of the optic properties of filters taking advantage of the interference technology and filters coated with a single metallic layer reflecting ir radiation
, the interference filters provide a more effective blocking of ir radiation in comparison with the currently used protective filters .

Answer:
the paper analyses the selected optical parameters of protective optic filters used for protection of the eyes against hazardous radiation within the visible ( vis ) and near infrared ( nir ) spectrum range .
 the indexes characterizing transmission and reflection of optic radiation incident on the filter are compared .
 as it follows from the completed analysis , the newly developed interference filters provide more effective blocking of infrared radiation in comparison with the currently used protective filters .


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:
acute cytomegalovirus ( cmv ) infection is common in both immunocompromised and immunocompetent patients worldwide.12 the infection is often asymptomatic .
symptoms , when they occur , include fever , cervical lymphadenitis , and arthralgia.3 rarely , acute cmv infection may be complicated by pneumonia , colitis , myocarditis , pericarditis , or hemolytic anemia.4 vascular events caused by acute cmv infection , including thrombosis of the venous or arterial vascular system , are rarely reported in the english literature .
we report a case of acute cmv colitis in an immunocompetent adult that was complicated by vascular thrombosis and pulmonary embolism .
further , we present a review of the literature regarding the association between vascular events and cmv infection in immunocompetent patients .
a 78-year - old man was referred to our emergency department with a 3-day history of diarrhea and fever .
he had no recent travel history , did not use steroids , and had not experienced recent trauma .
he used medication for hypertension and diabetes mellitus , both of which were well controlled . on admission ,
his vital signs were : body temperature , 38.8 ; blood pressure , 145/85 mmhg ; respiratory rate , 18/min ; and pulse rate , 90/min . on physical examination , his pulse was regular and he had no cardiac murmurs , his chest was clear without signs of respiratory distress , and his abdomen was soft with hyperactive bowel sounds .
laboratory tests showed a white blood cell count of 8,270/mm ( normal : 3,99010,500/mm ) , a platelet count of 199,000/mm ( normal : 140,000450,000/mm ) , a prothrombin time of 14.10 seconds ( control : 11.16 seconds ) , an inr of 1.21 , an activated partial thromboplastin time of 26.0 seconds ( control : 27.4 seconds ) , and crp level of 16.7 mg / dl ( normal : < 0.8 mg / dl ) . a coagulation profile , including protein c ( 80% , normal : 70%140% ) , protein s ( 75% , normal : 60%130% ) and anti - thrombin iii ( 95% , normal : 75%125% ) , was normal .
. colonoscopy demonstrated multiple giant ulcers with skip lesions in the distal colon , sparing the rectum ( fig .
multiple forceps - biopsy tissue samples , taken from the coloniculcers , were sent for pathological examination .
however , 5 days post - colonoscopy , the patient experienced dyspnea and severe hypoxemia , necessitating emergent endotracheal intubation and ventilation .
a chest radiograph obtained post - intubation revealed an engorged main pulmonary trunk with an abrupt cutoff of pulmonary vascularity in the distal portions bilaterally , indicative of the " westermark sign " ( fig .
subsequently , a ct scan of the chest was performed that showed several filling defects within the pulmonary trunk and main pulmonary arteries ( fig .
histological evaluation of the colonic biopsy specimens revealed cytomegalic cells with densely staining nuclei and intranuclear inclusion bodies in the epithelium ( fig .
these epithelial cells were positive for monoclonal anti - cmv antibody on immunohistochemical analysis , indicative of cmv infection ( fig .
the patient had no obvious risk factors for thrombosis , and had no family history of coagulopathy .
follow - up ct scan of the patient 's chest showed complete resolution of the pulmonary emboli .
acute cmv infection in immunocompetent patients is common worldwide , with seroprevalence rates ranging from 40% to 100% , depending on country , socio - economic conditions , and age.1 colitis is the most common manifestation of severe cmv infection.2 patients with cmv colitis are generally asymptomatic ; if symptomatic , they may present with diarrhea , fever , bleeding , abdominal pain , and perforation .
4 vascular events are a very rare manifestation of severe cmv infection in immunocompetent individuals.2 these vascular events include thrombosis of the portal , superior mesenteric , or splenic vein ; cerebral venous thrombosis ; deep vein thrombosis ; and life - threatening pulmonary embolism .
567 vascular complications may be discovered only several weeks after the initial diagnosis of cmv infection . however , abgueguen et al . proposed that venous thrombosis in immunocompetent patients with cmv infection may not be as rare as previously reported.8 although the pathogenesis of cmv - induced vascular events is unknown ,
several mechanisms have been postulated , including direct damage to endothelial cells , increased levels of hemostatic indicators , induction of smooth muscle proliferation , enhanced platelet - derived growth factor production , and the presence of antiphospholipid antibodies.91011 vascular thrombosis in immunocompetent patients is usually associated with predisposing factors such as heterozygous factor v leiden mutation , presence of antiphospholipid antibodies , heterozygous prothrombin gene mutation , protein c and/or protein s deficiency , or oral contraceptive use.12 in contrast , this patient had no family history of coagulopathy , was not bed - ridden , and had no other risk - factors for thrombosis .
it is , therefore , likely that cmv infection was the precipitating factor for pulmonary embolism . in the diagnosis of vascular events caused by cmv infection ,
doppler ultrasound and ct scanning are the most useful diagnostic modalities.6 treatment of cmv - associated pulmonary embolism includes immediate administration of antiviral agents and anticoagulants .
advanced age , male gender , presence of immune - modulating comorbidities , and need for surgical intervention all negatively influence survival.13 although the cost - effectiveness of investigating for acute cmv infection in patients presenting with thrombosis has not yet been established , we believe that serum samples for cmv infection should be obtained and endoscopic examination should be considered in patients with idiopathic thrombosis . in conclusion , although pulmonary embolism caused by acute cmv colitis in immunocompetent patients is extremely rare , it should be considered in patients who present with severe respiratory symptoms . to the best of our knowledge ,
this is the first report of an immunocompetent patient with acute cmv colitis complicated by vascular thrombosis with pulmonary embolism in which no other obvious underlying predisposing factor for thrombosis was identified .

Answer:
acute cytomegalovirus ( cmv ) infection occurs commonly in immunocompromised and immunocompetent patients , but is usually asymptomatic in the latter .
 vascular events associated with acute cmv infection have been described , but are rare .
 hence , such events are rarely reported in the literature .
 we report a case of pulmonary embolism secondary to acute cmv colitis in an immunocompetent 78-year - old man .
 the patient presented with fever and diarrhea .
 colonic ulcers were diagnosed based on colonoscopy findings , and cmv was the proven etiology on pathological examination .
 the patient subsequently experienced acute respiratory failure .
 pulmonary embolism was diagnosed based on the chest radiography and computed tomography findings .
 a diagnosis of acute cmv colitis complicated by pulmonary embolism was made .
 the patient was successfully treated with intravenous administration of unfractionated heparin and intravenous ganciclovir .