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:
procalcitonin ( pct ) is a 14-kd protein encoded by the calc-1 gene and synthesized physiologically by thyroid c - cells . under normal conditions , serum pct levels are negligible .
after shock or tissue injury ( i.e. burn , trauma , surgery ) or infections and sepsis , pct mrna expression has been documented in human extra - thyroidal tissues .
thus , systemic pct concentrations are considered as a component of the inflammatory response and as an acute - phase marker . in cardiac acute patients , data on pct
some studies [ 3 , 4 ] reported that pct levels were increased in acs patients on admission , whereas other investigations [ 5 , 6 ] documented that plasma pct concentrations were in the normal range in patients with uncomplicated acute myocardial infarction .
elevated concentrations of pct have been reported in patients with cardiogenic shock . in a more recent retrospective study , it was observed that cs patients showed high pct concentrations , especially in the presence of multiorgan failure ( mof ) and in absence of signs of infections ( cultures and clinical findings ) .
we recently   observed that the degree of myocardial ischemia ( clinically indicated by the whole spectrum of acs , from unstable angina to cardiogenic shock st - elevation following myocardial infarction ) and the related inflammatory - induced response are better reflected by crp ( which was positive in most acute cardiac care patients of all our subgroups ) than by pct which seems more sensible to a higher extent of inflammatory activation , being positive only in all cs patients . in these patients , the clinical interpretation of absolute pct values ( both in diagnostic and prognostic terms ) , represent a major challenge since they may be influenced by several factors , such as the degree of systemic inflammatory response , the coexistence of multiorgan dysfunction , the presence / absence of infections and finally by the time of measurements during hospital course ( i.e. the dynamics of pct levels ) .
no data are so far available on the dynamics of pct levels in patients with cardiogenic shock .
the aim of this preliminary investigation was therefore to evaluate the serum evolution of pct during intensive cardiac care unit ( iccu ) staying in a group of patients with cardiogenic shock ( cs ) following st - elevation myocardial infarction ( stemi ) submitted to primary percutaneous intervention ( pci ) with no laboratory or clinical sign of infection .
ten consecutive patients with cardiogenic shock following stemi were submitted to pci and then admitted to our 12-bed iccu in florence , a tertiary center , from 1 september 2008 to 31th march 2009 . to be eligible for the present study , all patients had to be free of infection at the time of blood sampling , as evidenced by both clinical and microbiological examinations , including urinary cultures and microbiological examinations of tracheal aspirate in mechanical ventilated patients and blood cultures . a clinical diagnosis of cardiogenic shock was made if all the following criteria were present : 1 .
systolic blood pressure persistently less than 90 mmhg or vasopressors required to maintain a systolic blood pressure of more than 90 mmhg ; 2 .
signs of hypoperfusion ( e.g. urine output less than 30 ml / hour or cold / diaphoretic extremities or altered mental status ) ; 3 .
clinical evidence of elevated left ventricular filling pressure ( e.g. pulmonary congestion on physical examination or chest x - ray ) .
pulmonary artery catheterization was not required when all clinical criteria and echocardiographic evidence of left ventricular dysfunction without mechanical complications were present .
the day after iccu admission blood samples were obtained for cardiac biomarkers ( tni < 0.15 ng / ml ) , leucocytes count ( 4000 - 10000/l ) , crp ( < 9 mg / dl ) , uric acid ( < 6.5 mg / dl ) , nt - pro brain natriuretic peptide ( nt - probnp , in males 0 - 50 yrs : < 88 pg / ml , > 50 yrs : < 227 pg / ml ; in females : 0 -50 yrs : < 153 pg / ml ; > 50 yrs : < 334 pg / ml )   and procalcitonin measurements ( normal values < 0.5 ng / ml ) .
transthoracic 2-dimensional echocardiography was performed on admission in order to evaluate left ventricular ejection fraction ( lvef ) .
apache ii ( acute physiology and chronic health evaluation ii ) score was also assessed .
the study design was approved by the local ethic committee and inform written consent was obtained for each patient .
statistical analysis was performed by means of spss 13.0 package ( spss inc , chicago , il ) .
data are reported as frequencies and percentages or means  s.d . and analyzed with fisher s exact test and student s t test , respectively .
since pct was determined once a day , its mean value for each day of hospital stay in either group of patients has been calculated and graphically plotted in order to obtain two linear regression lines , whose slopes have been subsequently compared by means of an f test .   in all analyses ,
table 1 shows the clinical characteristics of cs patients following stemi included in the study after pci .
clinical characteristics of patients included in the study . compared with survivors , dead patients exhibited higher values of apache ii score , as well as trend towards higher serum concentrations of troponin i , though it did not reach statistical significance .
no significant differences were detectable in regard to age , sex , infarct location , left ventricular ejection fraction , and mean arterial pressure between the two subgroups .
as depicted in table 2 , higher values of glycemia , nt - probnp and crp were detectable in dead patients in respect to survivors .
basal serum concentrations of procalcitonin were higher in ( dead ) survivors patients , though this difference did not reach statistical significance due to high values of standard deviation .
as depicted in figure 1 , the pattern of pct variations during iccu course was significantly different in cs patients who survived in respect to those who died ( survivors : slope = -3.760.71 standard error ; dead : slope = -0.810.35 standard error , p=0.004 ) .
the main finding of the present investigation , though preliminary and performed in a small subset of patients , is that the patterns of temporal pct variations throughout iccu course were heterogeneous in patients with cs and no clinical or laboratory signs of infection .
a progressive reduction in pct values was observed in cs patients who survived , whereas the lack of changes in pct concentrations was documented in cs patients who died .
conversely , basal absolute pct values were not significantly different between the two subgroups , since they exhibit a wide range of values in the overall population .
sponholz et al .   described the evolution of serum procalcitonin levels after uncomplicated cardiac surgery and observed a progressive return to normal levels within the first week .
peak pct levels were reached within 24 hours postoperatively and this increase seemed to be dependent on the surgical procedure , being more invasive procedures associated with higher pct levels , and on intraoperative events , including aortic cross - clamping time , duration of cardiopulmonary bypass and duration of surgery . in infected patients , pct levels were elevated throughout the first week postoperatively [ 19 , 20 , 21 ] , with a more pronounced trend in bacterial and fungal infections than in viral infections of sirs . [ 22 , 23 ] .
the authors concluded that the dynamics of pct levels , rather than absolute values , may be more important for identifying patients with infectious complications after cardiac surgery .
more recently prat et al .   confirmed a slight increase in pct values in the first postoperative day after cardiac surgery , in agreement with previous results [ 25 , 26 , 27 ] and with adamik et al .
, who showed that the development of postoperative complications after cardiac surgery with cardiopulmonary bypass was associated with increased postoperative neopterin and pct levels .
similarly , after heart transplantation , serum pct levels display a rise in response to surgery , with a peak on day two , whereas high peak levels with delayed return to normal values should lead to a search for inflammatory processes , as they are often associated with increased morbidity and mortality .
likewise , in patients with cardiogenic shock and no sign of infections we documented a reduction of pct levels only in survivors cs patients .
this time course of procalcitonin can probably be explained , both in postsurgical and in cs patients , by normal pct kinetic . in healthy subjects
the injection of endotoxin is followed by a rise in pct , reaching a maximum 24 hours thereafter .
the return of pct levels to normality within a few days in surgical patients ( after an uncomplicated postoperative course ) and in cs survivors patients can be explained by half - life of pct ( 18 to 24 hours ) , in absence of a further insult that might induce pct production .
our findings , along with those in cardiac surgery   strongly support the contention that the  dynamic
approach   may be more reliable that the static one ( that is the absolute single pct value ) especially in the challenging conditions characterized by a systemic inflammatory response , such as cardiac surgery and cardiogenic shock . indeed , in a cohort of unselected critically ill patients , jensen et al .
observed that a pct increase was an independent predictor of 90-day survival and that the pct day - by - day changes was able to identify critically ill patients at a higher risk of icu mortality . on the other hand ,
the initial  ct level did not predict mortality , even though many patients were admitted with a pct 1.0 ng / ml .
this suggests that several pct measurements should be made consecutively to assess the critically ill patient s infection - related mortality risk ( to monitor treatment of infection day - by - day ) . in our investigation
we further confirmed that higher values of nt - probnp are associated with increased mortality in cs patients   and that a more marked systemic inflammation ( as inferred by higher values of crp ) and higher severity score ( as indicated by apache ii ) were associated with an ominous prognosis .
the main limitation of the present investigation is represented by the small number of patients . however , the population is homogeneous , comprising patients with cardiogenic shock following stemi all submitted to pci , with no clinical and laboratory sign of infections .
it is interesting to note that , despite the small number of subjects , the behavior of pct was clearly detectable .
according to our preliminary findings , patterns of temporal pct variations throughout iccu course were heterogeneous in patients with cs following stemi submitted to pci and no clinical or laboratory signs of infection .
a progressive reduction in pct values was observed in cs patients who survived , whereas a lack of changes in pct concentrations was documented in cs patients who died .
our findings strongly support the contention that the  dynamic  approach may be more reliable that the static one ( that is the absolute single pct value ) especially in the challenging conditions characterized by a systemic inflammatory response , such as cardiogenic shock .
we further confirmed that higher values of nt - probnp are associated with increased mortality in cs patients and that a more marked systemic inflammation ( as inferred by higher values of crp ) and higher severity score ( as indicated by apache ii ) were associated with an ominous prognosis .

Answer:
introductionprocalcitonin concentrations are considered as a component of the inflammatory response and as an acute - phase marker , after shock or tissue injury ( i.e. burn , trauma , surgery ) or infections and sepsis .
 no data are so far available on the dynamics of procalcitonin levels in patients with cardiogenic shock following st - elevation myocardial infarction , with no clinical or laboratory sign of infection.methodswe evaluated procalcitonin values every day during intensive cardiac care staying in ten cardiogenic shock patients admitted to our intensive cardiac care unit . nt - pro brain natriuretic peptide , c reactive protein and apache ii score were also assessed.resultssix patients survived , whereas 4 patients died .
 a progressive reduction in procalcitonin values was observed in cardiogenic shock patients who survived , whereas the lack of changes in procalcitonin concentrations was documented in cardiogenic shock patients who died ( survivors : slope = -3.76 ; dead : slope = -0.81 , p=0.004 ) .
 furthermore , higher values of glycemia , nt - pro brain natriuretic peptide and c reactive protein ( as well as higher apache ii scores ) were detectable in dead patients in respect to survivors.conclusionsin our preliminary study we observed that in patients with cardiogenic shock and no sign of infections a reduction of procalcitonin levels was detectable only in survivors . moreover , higher values of nt- brain natriuretic peptide , a marked systemic inflammation ( higher values of c reactive protein ) and higher severity score ( as depicted by apache ii ) are associated with an ominous prognosis in cardiogenic shock patients .


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:
technetium-99 m ( tc-99 m ) in complex with methylene - diphosphonate ( mdp ) is a commonly used substrate in radionuclide bone imaging .
bone scans utilizing this radiotracer are very sensitive and enable nuclear medicine physicians to screen for various osseous abnormalities and pathologies .
localization of the radiotracer is accomplished through the exchange of tc-99 m mdp for phosphate compounds during active bone remodeling , and aggregation is subsequently detected using a gamma camera . even though the utilization of tc-99 m mdp bone scintigraphy is useful for identifying various physiologic abnormalities , its overall specificity is limited primarily by the lack of anatomic detail .
it is therefore important to utilize the patient 's medical history , in conjunction with other forms of imaging , to aid in differentiating potential pathologies . here ,
we present a case in which tc-99 m mdp bone scintigraphy was utilized to raise concern for a serious abnormality despite relatively occult findings by conventional imaging modalities .
a 70-year - old male presented with mild left hip pain and was found to have an elevated serum alkaline phosphatase ( alk ) level of 770 units / l .
unfortunately , due to a language barrier , a complete medical history could not be obtained . in light of the patient 's elevated alk level ,
the planar whole body images [ figure 1a ] of the tc-99 m mdp bone scan demonstrated intense diffuse uptake extending from the left femoral head to the proximal shaft of the femur .
initially , we felt this type of appearance could be compatible with early paget 's disease given the markedly elevated alk , despite the absence of apparent structural deformities .
70-year - old male with mild left hip pain and elevated alkaline phosphatase diagnosed with radiogenic osteosarcoma .
( a ) the planar whole body images of the technetium-99 m methylene diphosphonate bone scan demonstrates intense diffuse uptake extending from the left femoral head to the proximal shaft of the femur ( double ended arrow ) .
( b ) the plain film of the left hip depicts three previously unreported fixation screws surrounded by osteopenic lesions ( arrow ) in the femoral neck and head . to confirm the initial diagnosis ,
the patient was sent directly for an x - ray [ figure 1b ] . however , the pattern of multifocal sclerosis ( cotton wool appearance ) that would be expected of paget 's disease was not present . instead , the radiograph demonstrated three previously unreported fixation screws , used to repair a femoral neck fracture ( later discovered to have occurred 1 year ago ) . surrounding the screws were poorly defined osteopenic , potentially lytic lesions in the femoral neck and femoral head [ figure 1b ] .
correlation of the tc-99 m mdp bone scan with the x - ray changed the initial diagnosis from suspected paget 's disease to a differential of malignancy / metastasis , reparative phase of osteonecrosis , osteomyelitis , or reactive osteolysis to the fixation screws . though simple loosening of the fixation screws could have explained the patient 's mild hip pain , the activity demonstrated by the bone scan was much too diffuse and intense to support this diagnosis . to evaluate for metastatic disease ,
a computed tomography scan of the chest , abdomen , and pelvis was ordered the following day .
evaluation of the scan of the left hip was limited due to streak artifact from the screws ; however , it was still possible to appreciate some mixed lytic / sclerotic changes in the native bone [ figure 2a and b ] .
even though these changes raised the suspicion of osseous malignancy or metastasis , they were not pathognomonic , as hardware loosening , osteopenia , and degenerative changes could have a similar appearance .
however these findings in combination with the bone scan findings , provided enough suspicion of a pathology sinister enough to refer the patient for surgical hardware revision with potential biopsy .
70-year - old male with mild left hip pain and elevated alkaline phosphatase diagnosed with radiogenic osteosarcoma .
( a and b ) computed tomography of the pelvis reveal mixed lytic / sclerotic lesions ( arrows ) within the native bone , although evaluation of the left hip was limited due to streak artifact as seen on the two axial slices in figure 1 .
surgical exploration of the left hip revealed a grossly abnormal appearance of the left proximal femur with areas of hemorrhagic bone surrounding lytic lesions .
histologic study of the biopsy [ figure 3 ] demonstrated sarcomatous , spindle shaped cells with adjacent tumor osteoid production ; represented by eosinophilic , amorphous , fibrillary deposits between individual or small aggregates of tumor cells .
70-year - old male with mild left hip pain and elevated alkaline phosphatase diagnosed with radiogenic osteosarcoma .
histologic examination of the curettage ( using hematoxylin and eosin stain , 10 ) reveals sarcomatous , spindle shaped cells ( white arrows ) with adjacent tumor osteoid production ( black arrows ) ; represented by eosinophilic , amorphous , fibrillary deposits ( white arrows ) between individual or small aggregates of tumor cells ( black arrows ) . in context , the presence of osteosarcoma was highly unlikely as there have been no case reports of primary osteosarcomas occurring in a site of a fracture that was surgically repaired 1 year prior .
additionally , the distal femur would be a far more likely site for a primary osteogenic sarcoma to occur .
however , upon further interrogation of the patient 's past medical history , it was discovered that the patient had prostate cancer 11 years ago .
given the standard of care at that time , one could surmise that he was treated with 60 - 70 gy of targeted external beam radiation to the prostate .
the dose that he received and the time frame since receiving his radiation would be compatible with radiogenic osteosarcoma as there is a latency period of about 10 years .
the repaired stress fracture 1 year prior was potentially pathologic from the malignancy , but was most likely missed due to the slightly atypical radiographic appearance on the plain film x - ray performed in the surgeon 's office .
tc-99 m mdp bone scans are very sensitive tests for detecting a wide array of abnormalities within the bone . despite its comprehensive applicability ,
it is limited in identifying specific diseases and pathologies ; often relying on the addition of other investigative modalities to reach a final diagnosis . here , a tc-99 m mdp bone scan was used to identify the presence of abnormal bone remodeling , which led to further imaging work - up and confirmatory biopsy .
osteosarcomas are particularly sensitive to tc-99 m mdp bone scans as their pathology involves active bone remodeling .
however , its presence here was unexpected due to the atypical location on the bone scan and the limited available medical history ( due to a language barrier ) . when paired with the patient 's medical history of radiation treatment and recent fracture ,
the femur would have been exposed to scatter and bremsstrahlung radiation from its proximity to the treatment field . additionally , the 10-year latency period to developing malignancy is typical for post - external beam radiation therapy induced malignancies .
the tc-99 m mdp bone scan demonstrated its value by raising the suspicion for a more sinister process in the left hip than was seen in radiographic appearance on plain film .
this case demonstrated the value of tc-99 m mdp bone scintigraphy as an initial detector of bone abnormalities .
its sensitivity prevents it from identifying specific pathologies without the aid other investigative methods as depicted in this case .
this case also underscores the importance of considering the bone scan findings in conjunction with the patient 's clinical history and anatomic imaging . by using all this information in combination
, we were able to sift through the differential and refer the patient for appropriate management .

Answer:
we present a case of a 70-year - old male who was referred for a technetium-99 m methylene - diphosphonate bone scan for mild left hip pain and an elevated alkaline phosphatase level of 770 units / l .
 no additional information was provided and the patient 's history was limited due to a language barrier .
 we were able to ascertain that the patient had a remote history of prostate cancer , which had been treated with radiation .
 originally , we felt the bone scan was compatible with paget 's disease ; however , further work - up revealed the presence of osteosarcoma , which was potentially radiation - induced .


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:
preoperative anxiety or stress have been thought to delay gastric emptying and increase gastric acidity and is therefore considered one of risk factors related with aspiration pneumonitis . in large series of olsson
et al . ( 1 ) , it was reported that pain and anxiety were able to be important mechanisms of decreasing intestinal motility especially in emergency surgical cases .
similarly , outpatients tend to have increased gastric fluid , presumably because of anxiety ( 2 ) .
cote et al . ( 3 ) found that more anxious children had a higher gastric acid content , although the difference was of questionable clinical significance .
more recently , clinical studies using various methods , however , have failed to confirm any correlation between anxiety and gastric function ( 4 - 6 ) .
the purpose of this study was to clarify whether anxiety affects the preoperative actual acidity and volume of gastric fluid with several contributing factors such as sex , age , fasting time , hypoglycemic status controlled in female patients undergoing elective gynecologic surgery under general anesthesia .
after obtaining an approval from the committee of ethics on human study in our hospital and an informed consent from each patient , we studied asa physical status i - ii 96 female patients aged between 16 and 60 yr who underwent elective gynecological surgery under general anesthesia .
patients with a history of any gastrointestinal disorder , or who were receiving antacids or h2 receptor blockers , or any other medication , which would interfere with gastrointestinal function , were excluded from the study .
a power analysis was performed to determine the sufficient sample size required to establish a significant difference in the gastric variables and in the percentage of patients at risk for aspiration pneumonia based on the results of a preliminary study , using an -value of 0.05 , and power of 0.8 .
, patients were asked to complete the visual analogue scale with regard to the level of anxiety ( range 0=no anxiety at all , to 10=extremely anxious ) in the preoperative preparing unit .
the patient 's data including vital signs , oral fasting time , and medical and surgical history were collected from interview and the medical records .
immediately after tracheal intubation using 100 - 120 mg of propofol and 0.5 mg / kg of rocuronium , a 14-f multiorifice nasogastric tube ( levin tube , yushin medical , shiheung , korea ) was inserted upto 60 cm from the incisor . proper position of the nasogastric tube was verified by auscultation over the epigastrium by injecting 10 ml of air .
subsequently , the gastric fluid was aspirated gently to a syringe using mild negative pressure .
this maneuver was repeated in both slightly left- and rightward tilted positions and in trendelenburg and reverse trendelenburg position to ensure maximum emptying of the stomach .
a standard general anesthesia with enflurane in nitrous oxide , oxygen , and rocuronium was provided for the surgery .
the volume of gastric fluid and ph were measured using a metered cylinder and a ph meter twice ( model-920a , orion research inc .
blood concentration of glucose was measured at the same time by using a blood glucose meter ( surestep , lifescan inc . , milpitas , ca , u.s.a . ) .
blood samples taken from the arm opposite to the intravenous infusion were collected and centrifuged ; the serum was separated and stored at -70. double antibody gastrin method is a radioimmunoassay technique for gastrin designed for the quantitative measurement of gastrin in serum , which utilizes labeled synthetic iodinated human gastrin ( shg i-17 ) ( 7 ) .
visual analogue scale ( vas ) of preoperative anxiety was 3.822.1 and the range was from 0 to 8.5 .
we classified the subjects into 2 groups , those presenting vas less than 5 ( low - anxiety group , l - group ) , and remains ( high - anxiety group , h - group ) .
statistical analysis was performed by paired t - test with bonferroni correction for demographic data .
the mann - whitney u - test and chi - square test were used to analyze the anxiety scores , gastric ph and volume of the gastric fluid , serum gastrin concentrations , and the number of patients at risk for aspiration pneumonitis ( gastric ph < 2.5 and volume > 25 ml ) in order to compare both groups .
spearman 's correlation coefficient was used to measure the association between anxiety and gastric residues .
the two groups were comparable with regard to age , weight , height , diagnosis , fasting time , and preoperative blood glucose level .
preoperative heart rate , systolic and diastolic blood pressures were similar in the both groups ( table 1 ) .
the preoperative anxiety score ( vas ) of l - group was 2.41.4 , and that of h - group was 6.00.9 .
the mean gastric acidity and volume of the two groups were not statistically different : ph of l - group , 3.01.8 ( range : 1.3 - 7.3 ) , ph of h - group , 3.02.0 ( range : 1.3 - 7.8 ) , volume of l - group , 15.311.7 ml ( range : 0 - 50 ) , and volume of h - group , 11.811.8 ml ( range : 0 - 70 ) .
there were 9 ( 15.3% ) patients considered to be ' at risk : gastric ph < 2.5 and volume > 25 ml ' in the l - group , and 1 ( 2.7% ) in the h - group ( p<0.05 , fig .
the mean serum gastrin concentration in the l - group was 21.69.8 pg / ml , and that in the h - group was 20.211.0 pg / ml ( p = ns ) .
the ph and volume of preoperative gastric contents were not significantly associated with the preoperative anxiety ( fig .
, there were no epistaxes , vomiting , ventilatory problem , or other serious complications .
the main finding of this study was that there are no differences in preoperative gastric ph and volume between the two groups , but there are more patients ' at risk ' for aspiration pneumonitis in the low anxiety group .
several authors reported that preoperative anxiety did not prolong gastric emptying nor had influence gastric acidity and volumes in adults and children ( 3 - 5 , 8 , 9 ) .
( 6 ) evaluated the relationship between oral premedication , preoperative anxiety , and gastric contents in patients having elective surgery .
gastric volume and ph did not correlate with the type of premedication or the level of anxiety .
( 9 ) observed that a smaller gastric fluid volume in highly anxious pediatric patients compared to children with low anxiety level .
in addition , the increased sympathetic tone disturbs gastric secretion through the adrenergic neurons in the splanchnic nerve . in our results , however , we could not detect any differences in serum gastrin concentration which has been known as a major hormone regulating secretion of gastric juice .
interestingly , we also observed that the number of ' patients at risk : gastric ph < 2.5 and volume > 25 ml ' was much greater in less anxious patients .
the smaller gastric volume of highly anxious patients was consistent with the report of kawana et al .
therefore , perhaps gastric motility , not gastric secretion , was altered by neural or endocrine mechanisms in the anxious patients .
traditionally , the -adrenergic system has been shown to exert an inhibitory action on gastric emptying in normal circumstances ; isoprenaline decreases and propranolol increases stomach emptying ( 10 , 11 ) .
in contrast , christensen and stadil ( 12 ) reported that corticosteroids and adrenaline , in physiological concentrations , increase the acidity of gastric secretions .
we did not measure hormones including epinephrine , norepinephrine , or any other stress hormones .
although our results did not support any association between the level of preoperative anxiety and gastric volume and ph , preoperative anxiety seems to decrease the risk of aspiration pneumonitis .
further studies are necessary to clarify neurogenic and endocrine regulatory mechanisms of anxiety on preoperative gastric function . since gastric secretion and movements
are controlled by a very complicated mechanism and gastric residuals are affected by many factors , a well controlled study design is difficult to create .
we tried to minimize other influencing factors for gastric secretion and emptying such as sex , age , fasting time , preoperative blood glucose concentration , and premedication .
no attempt was made to take account of the phase of menstrual cycle or circadian variation because the effect of both has been shown not to apply to gastric emptying of liquids ( 13 , 14 ) .
this may be due to environmental factors including unpredictable delay of the operation , or protocol violation by the patient such as skipping the previous evening meal due to preoperative anxiety and tension .
the technique of gastric aspiration can not guarantee complete gastric emptying , and volumes recorded reflect only the maximum gastric aspirate obtained at the time , with every effort made to increase yield by manipulation of the tube .
dye absorption technique and fiberoptic gastroscopy are more reliable than blind aspiration ( 15 ) , but are more complicated , time consuming , and clinically limited methods .
we evaluated the patients ' anxiety in terms of vas based on the study of kindler et al .
they reported that the vas allows effective measurement of preoperative anxiety and detection of patients ' anesthetic concerns .
we conclude from the current data that there are no significant differences of preoperative gastric ph and volumes between high and low anxious patients .
however , the number of patients ' at risk ' for aspiration pneumonitis was much more in low anxious patients .
the results suggest that a low level of preoperative anxiety can be considered a risk factor in connection with aspiration pneumonitis .

Answer:
the aim of this study was to evaluate the effect of preoperative anxiety on the gastric ph and volume .
 we studied 96 female patients aged 16 - 60 yr who underwent elective gynecological surgery .
 we classified the subjects into 2 groups , those presenting preoperative anxiety scores using visual analogue scale ( vas , 0 - 10 ) less than 5 ( l - group , n=59 ) , and those with 5 and more ( h - group , n=37 ) .
 immediately after tracheal intubation , gastric contents were aspirated using a 14-f multiorifice nasogastric tube .
 the gastric acidity and volume of the two groups were not statistically different .
 mean ph were 3.01.8 and 3.02.0 in each group ( l - group and h - group ) and mean gastric volume ( ml ) were 15.311.7 and 11.811.8 , respectively .
 nine ( 15.3% ) patients in the l - group were considered to be ' at risk i.e. gastric ph < 2.5 and volume > 25 ml ' and one patient ( 2.7% ) in the h - group ( p<0.05 ) . the mean serum gastrin concentrations in both groups were similar ( 21.69.8 vs. 20.211.0 pg / ml ) .
 the ph and volume of preoperative gastric contents were not correlated with the preoperative anxiety .
 the results suggest that a low level of preoperative anxiety can be considered a risk factor for aspiration pneumonitis .


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:
mouth opening is a clinical parameter , which we encounter routinely in our daily practice .
a known normal range of mouth opening is necessary to enable the clinician conduct a thorough oral examination conveniently
. a reduced mouth opening capacity ( moc ) may be one of the first clinical signs of pathological changes and traumatic conditions in the masticatory system .
early recognition of decreased or limited mouth opening is necessary for a prompt and efficient approach to diagnosis and to plan out the treatment options judiciously . to make a diagnosis of decreased mmo , it is essential to establish what constitutes the normal mmo for children of different age .
research has shown that the measurement of mouth opening varies significantly with age , gender , and race .
numerous studies across the world have characterized the mmo in their adult as well as pediatric population .
however , very little data exist on normal mmo in the indian pediatric population . in a growing population ,
furthermore , most existing datasets are of limited value because they do not cover the entire age range . despite these limitations ,
the existing normal values indicate a significance of growth on the mmo and a wide range of normalcy within a certain age category . in india , it is fairly common to report the mouth opening in terms of finger breath in our daily practice .
understandably , this is semi - quantitative measurement subject to many variations . hence , establishing numerical value will be of significant value
. the present study aims to establish age- and height - related percentiles for the mmo of healthy children and adolescents which may serve as a basis for various studies and will have the clinical utility in treatment and diagnosis of diseases directly or indirectly affecting the mouth opening .
the present study was carried out in the pediatric outpatient clinic in a tertiary care center in western india .
a total of 985 children , 560 males and 425 females , in the age range of 518 years were studied .
the children were asked to open their mouth maximally unassisted till no further opening was possible .
mmo was measured when the children rested their heads against a firm wall surface in an upright position .
the distance from the incisal edge of the upper incisor teeth to the incisal edge of the lower incisor teeth was measured using a calibrated fiber ruler , and the findings were recorded in millimeters [ figure 1 ] .
three readings were recorded for each individual , and their average was recorded as the final reading . to control for inter - examiner and intra - examiner reliability ,
the age , sex , height , and weight of all the children were recorded .
method of measuring interincisal distance with fiber ruler the study included all the children between the ages of 518 years of age attending pediatric outpatient clinic , having all the incisors and able to understand and cooperate with the investigators .
exclusion criteria for the study were children with ( 1 ) habit of smoking , tobacco , or betel nut chewing , ( 2 ) no natural front teeth , ( 3 ) previous maxillofacial trauma , ( 4 ) oral malignancies , ( 5 ) angular cheilosis or oral ulcers affecting mouth opening , ( 6 ) chronic systemic disease , and ( 7 ) pain while opening mouth .
this study was approved by the research ethics committee of the institute . as children involved in the study were minors ,
weight and height for each child were obtained using a standard calibrated anthropometric scale , with precision of 100 g and 1 mm , respectively .
mean mmo values were analyzed according to age , height , and weight ranges , which were established appropriately for statistical analysis .
hence , the sample was divided according to age and height : 13 age groups ( between 5 and 18 years ) and 10 height groups of 10 cm each ( 8695 cm ; 96105 cm ; 106115 cm ; 116125 cm ; 126135 cm ; 136145 cm ; 146155 cm ; 156165 cm ; 166175 cm ; 176185 cm ) were assigned .
continuous variables are reported as mean  standard deviation . to determine correlation of mouth opening with age and height ,
a linear regression analysis was performed and statistical significance was tested by the application of t - test and f - test .
the statistical analysis has been performed using open source software r version 3.0.1 . of r foundation , vienna , austria .
mean mmo values were analyzed according to age , height , and weight ranges , which were established appropriately for statistical analysis .
hence , the sample was divided according to age and height : 13 age groups ( between 5 and 18 years ) and 10 height groups of 10 cm each ( 8695 cm ; 96105 cm ; 106115 cm ; 116125 cm ; 126135 cm ; 136145 cm ; 146155 cm ; 156165 cm ; 166175 cm ; 176185 cm ) were assigned .
continuous variables are reported as mean  standard deviation . to determine correlation of mouth opening with age and height ,
a linear regression analysis was performed and statistical significance was tested by the application of t - test and f - test .
the statistical analysis has been performed using open source software r version 3.0.1 . of r foundation , vienna , austria .
our study included a total of 985 children with 560 males and 425 females among them .
the median age for the entire sample is 10.5 years , and median height was 130 cm for girls and 130139.99 cm for boys .
the mean mmo was 43.5  5.19 for girls and 44.24  5.84 cm for boys .
table 1 presents the number of children in each age group with mean moc values ( mm ) for indian children .
table 2 presents the mean moc values ( mm ) for the indian children in each height group .
the scattered diagram relation of moc with age and height was plotted [ figure 2a and b ] .
number of individuals in each age group for boys and girls with mouth opening capacity values ( mm ) variation in mouth opening with height ( a and b ) the scattered diagram showing relation of mouth opening capacity with age and height diagrammatic representation of mean mouth opening capacity value according to the height there was a significant difference between the moc of male and female in all age groups .
a linear relationship was observed between the mouth opening and age but more significantly with height in entire sample , with correlation coefficient of 0.63 , which showed that moc increases as the age and height increases , and this relation was found to be statistically significant ( p < 0.0001 ) .
as the height reflects the skeletal growth , we also found that the mmo is more significantly associated with height than age .
the dataset was entered into the r program for the creation of age - related percentiles .
best results were achieved using the following settings : l = 1 , i.e. , l constant , set to l = 0.65 by the program , m = 5 , s = 2 for girls , and l = 1 , set to 0.5 by the program , m = 7 , s = 2 for boys . table 3 depicts four linear regression models evaluating impact of age ( model 1 ) , height ( model 2 ) , age and height ( model 3 ) , and age , height , and gender ( model 4 ) on moc . in isolation ,
age and height significantly impact mouth opening . however , impact of height on mouth opening is more significant than that of age .
further , when age and height were considered together , it was only height that had influenced moc and not age .
norms  could be designated for age with gender and height with gender [ tables 47 ] .
age - related percentiles for moc in boys and girls are given in figure 4a and b. height - related percentiles for moc in boys and girls are given in figure 5a and 5b .
linear regression models for mouth opening capacity age - related percentiles of mouth opening capacity for males ( in mm ) age - related percentiles of mouth opening capacity for females ( in mm ) height - related percentiles of mouth opening capacity for males ( in mm ) height - related percentiles of mouth opening capacity for females ( in mm ) ( a and b ) age - related percentiles for mouth opening capacity in boys and girls ( a and b ) height - related percentiles for mouth opening capacity in boys and girls
the dataset was entered into the r program for the creation of age - related percentiles .
best results were achieved using the following settings : l = 1 , i.e. , l constant , set to l = 0.65 by the program , m = 5 , s = 2 for girls , and l = 1 , set to 0.5 by the program , m = 7 , s = 2 for boys .
table 3 depicts four linear regression models evaluating impact of age ( model 1 ) , height ( model 2 ) , age and height ( model 3 ) , and age , height , and gender ( model 4 ) on moc . in isolation ,
age and height significantly impact mouth opening . however , impact of height on mouth opening is more significant than that of age .
further , when age and height were considered together , it was only height that had influenced moc and not age .
norms  could be designated for age with gender and height with gender [ tables 47 ] .
age - related percentiles for moc in boys and girls are given in figure 4a and b. height - related percentiles for moc in boys and girls are given in figure 5a and 5b .
linear regression models for mouth opening capacity age - related percentiles of mouth opening capacity for males ( in mm ) age - related percentiles of mouth opening capacity for females ( in mm ) height - related percentiles of mouth opening capacity for males ( in mm ) height - related percentiles of mouth opening capacity for females ( in mm ) ( a and b ) age - related percentiles for mouth opening capacity in boys and girls ( a and b ) height - related percentiles for mouth opening capacity in boys and girls
patients with temporomandibular joint diseases , craniofacial syndromes , maxillofacial trauma , oral malignancies and those who have been treated for these conditions often have complaint of restricted mouth opening . as with any other disease or condition ,
the aim of treatment of disorders affecting mouth opening is to restore the mouth opening to its normal value , hence the relevance of establishing normal values .
a large number of methods have been described in the literature to measure the mouth opening .
the measurement most often used to assess mouth opening is the interincisal distance attained during active opening by the subject .
this method underestimates the movement of the mandible as it does not include the overbite .
however , as pointed by mezitis et al . , the functional opening of the mouth is more important .
sufficient mouth opening to allow normal social function is clinically important for the patients and adequate access to the oral cavity for clinicians , which in effect is the interincisal distance without consideration for the overbite .
hence , the interincisal distance has been used as a measurement of mmo in this study .
an advantage of the incisal edge distance is that the measuring point is relatively more consistent , permanent , and more easily determined .
wood and branco examined three methods of measuring interincisal distance and concluded that direct measurement using a ruler was the most accurate .
described how the mmo decreases in order of forward , natural , and retracted head positions . in the present study ,
the mmo was measured when the subjects rested their heads against a firm wall surface in an upright position to eliminate the possible influence of different head positions .
mouth opening is influenced by a number of factors in children as they are in the period of skeletal growth .
the age , weight , height , gender , and race affect the mouth opening .
rothenberg noted a significant relationship between the maximum vertical opening of the mouth and age , among 189 caucasian children , aged 414 years .
the present study also reported a gradual increase in mmo in different age groups of children .
a few studies have observed a gender difference in mmo among children . in the present study , a statistically significant difference was observed in between boys and girls in various age groups .
the study also revealed a definitive correlation between mmo and height as well as age .
rothenberg also observed a positive correlation between mmo values in relation to weight and height in children aged 414 years of age group .
the observed gradual increase in mmo with increasing age , height , and body weight , as found in the present study , is due to changes in the temporomandibular joint apparatus , facial morphology , muscle development , and growth of cranial base and mandible , particularly in length . although age has the significant influence on the mmo values , a definite and stronger correlation exists between mmo and height .
children with poor nutrition often have stunted growth , and their skeletal growth is hampered .
in such cases , measurement of mmo will not correspond to the established norm for the age since the height is unaccounted for , in these malnourished children from lower socioeconomic group .
in such cases , to measure height by age can give a false - positive value of reduced mouth opening .
this study is therefore providing the normal percentile for different height groups for the first time .
these data are important because a high number of complex surgical procedures are routinely performed in this part of the world without a proper reference value for established norms .
assessment of mouth opening is an important part of clinical examination for the physician , surgeon , or clinician involved in the treatment of head and neck disorders and dental disorders . to diagnose an abnormality , knowledge of normal values is very important .
reference to international data is obviously not justified as the mouth opening is clearly varied among different ethnicities . to the best of our knowledge
, this data sample of 985 unselected children covers the entire age range of indian children where unassisted mouth opening can be measured .
we believe that these percentiles will therefore be of great importance for future studies as well as clinical assessment of indian children with affections of the masticatory system .

Answer:
background and aim : maximal mouth opening ( mmo ) is used as a marker of masticatory pathology .
 however , mmo among children varies considerably with their age , height , sex , and race . while accurate percentile of normal mouth opening and relationship with anthropometric measurement are not precisely defined for the indian population , we designed prospective , observational study to define the percentiles for normal mmo in our children.methods:a total of 985 children , 560 males and 425 females , in the age range of 518 years attending the pediatric clinic in a tertiary care center in western india were studied .
 in addition to the basic demographic data , mmo was measured in these children .
 the children were asked to open their mouth maximally until no further opening was possible .
 the distance from the incisal edge of the upper incisor teeth to the incisal edge of the lower incisor teeth was measured using a calibrated fiber ruler .
 statistical analysis was performed to assess the impact of other anthropometric measures such as age , gender , and height on mmo.observations:the mean mmo for males was 44.24 ( 5.84 ) mm and for females was 43.5 ( 5.19 ) mm .
 age- and height - related percentiles were created for girls and boys separately , showing the 5th , 10th , 25th , 50th , 75th , 90th , and 95th percentiles from 5 through 18 years of age with 86185 cm height.conclusion:the mmo percentile range for different age and height groups is established for the normal children .
 the mouth opening seems to increase with the age and especially with the height as per the skeletal growth .
 height affects mouth opening more than the age .


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:
emergency peripartum hysterectomy ( eph ) is a major surgical venture invariably performed in the setting of life threatening hemorrhage during or immediately after abdominal and vaginal deliveries [ 15 ] . despite advances in medical and surgical fields
, post partum hemorrhage continues to be the leading cause of maternal morbidity and mortality .
eph is the most dramatic operation in modern obstetrics and is generally performed when all conservative measures have failed to achieve haemostasis in the setting of life threatening hemorrhage . the unplanned nature of the surgery and the need for performing it expeditiously , compound matters .
moreover the acute loss of blood renders the patient in a less than ideal condition to undergo emergency surgical intervention .
the predominant indications for eph are placenta previa / accreta and uterine atony and eph in some of them is unavoidable . however recognizing and assessing patients at risk and
appropriate and timely intervention would go a long way in ensuring a better outcome in this otherwise difficult situation .
hysterectomy following cesarean section ( cs ) was first described by porro , and was used to prevent maternal mortality due to post partum hemorrhage .
the reported incidence of eph varies from 0.24 to 8.9 per 1000 deliveries [ 16 ] , ranging from 0.33(netherland ) , 0.2 ( norway ) , 0.3 ( ireland ) , 0.5 ( israel ) , 0.63 ( saudi arabia ) and 1.2 to 2.7 per 1000 deliveries in usa [ 25810 ] . a difference in the incidence of eph is noted following vaginal delivery and cesarean section .
while the incidence of eph after vaginal delivery varies from 0.1 to 0.3/1000 deliveries and is rather constant between european and us studies , the incidence of eph following cs varies widely between 0.17 and 8.7/1000 deliveries .
this is attributed to the proportion of women with previous cs with the concomitant risk of placenta previa andaccreta [ 16 ] .
the risk factors for post partum hemorrhage include coagulopathies , uterine atony , retained products of conception , precipitate or prolonged labor , fetal macrosomia or multiparity , maternal obesity and previous primary post partum hemorrhage [ 16814 ] .
according to one report the indication for eph which was uterine atony in 43.45% and placenta previa or accreta in 33.9% cases in 1984   changed 9 years later to placenta accreta ( 45% ) and uterine atony in 20% of the cases .
similar findings are reported by others with abnormal placentation as the predominant indication , the incidence ranging from ( 45 to 73.3% ) ; and uterine atony in ( 26.6% to 35.6% ) [ 18815 ] . in recent years
, abnormal placentation has become a more common indication due to the greater number of pregnant women with previous cesarean section deliveries [ 16 ] .
the incidence of previous cesarean section ranges between 59.8% in patients with adherent placenta and 75% in patients with placenta previa . in view of several such reports ,
association between abnormal placentation and cesarean delivery has been suggested and the high incidence of eph is directly related to the increasing number of cesarean sections [ 1616 ] .
this was further substantiated by another report where the incidence of placenta previa which was 1.9/1000 after one previous cs , increased by 47 fold to 91/1000 in patients with four previous cs .
patients with placenta previa and scarred uterus had 16% risk of undergoing eph compared to 3.6% in patients with unscarred uterus .
advancing age and parity are also reported to be important risk factors in developing placenta previa and accrete .
the incidence of eph was higher in patients with placenta previa and accreta than in patients with placenta previa alone .
the combination of factors including high parity , number of previous cesarean sections , abortion , previous curettage , strongly increased the likelihood of placenta previa and increased risk of abnormal adherent placenta .
therefore , it appears prudent for the obstetrician to prepare for the possibility of eph for massive hemorrhage in patients undergoing cesarean section with these risk factors . of concern
however , is the limited experience of performing emergency hysterectomy among the younger obstetricians as according to one report from netherlands , the average chance of performing one eph is once in 11 years .
the decreasing rate of abdominal hysterectomy for gynecological conditions in recent years does not help matters with regard to gaining this valuable experience .
this implies that more effort should be undertaken to recognize the potential risk of patients requiring eph and the need for involvement of an experienced obstetrician in the management at an early stage .
eph being performed by an experienced surgeon is reported to significantly reduce the operating time , number of units of blood transfusion and hospital stay .
the predisposing risk factors can be determined to a certain extent by performing antenatal ultrasound with color doppler and magnetic resonance imaging ( mri ) [ 1820 ] .
however , the limiting factor is the high cost of mri and extensive experience needed .
the measures include uterotonic drugs , uterine or hypogastric artery embolisation , hemostatic sutures , uterine or internal iliac artery ligation .
conservative management is of particular importance in patients who are young , have low parity and who are haemodynamically stable .
however while there are reports of 96% success rate following uterine artery ligation   there are others who have achieved success in only 39.4% of these cases .
the choice between conservative management and eph should be individualized . in situations where conservative treatment is likely to fail or has failed , there should be no further delay in performing eph as delay leads to increase in blood loss , transfusion requirement , operative time , dic , and increased possibility of admission to icu [ 16 ] .
uterine atony is an indication for eph in 20.6% to 43% of the cases [ 16817 ] .
while this was traditionally the leading cause for eph the incidence has reduced due to the use of newly developed pharmacologic treatment strategies including prostaglandins .
multiparity and oxytocin use for uterine stimulation were found to be the risk factors for uterine atony requiring eph [ 16 ] .
combs et al in their large case control study of patients with post partum hemorrhage reported that pre - eclampsia , nulliparity , twins , induction , prolonged labor and augmentation were all identified as independent risk factors for uterine atony .
patients with uterine rupture as an indication for eph ranged from 11.4% to 45.5% . the risk factor for
this would be multiple previous cesarean sections with a scarred uterus ( figure 1 ) .
total hysterectomy is the recommended surgical method of eph due to the potential risk of malignancy developing in the cervical stump and the need for regular cytology and other associated problems such as bleeding or discharge associated with the residual cervical stump .
currently the proportion of subtotal hysterectomy performed for eph ranges from 53%   to 80% .
the proponents of subtotal hysterectomy report a lesser blood loss , a reduced need for blood transfusion , reduced operating time and reduced intra and postoperative complications .
total hysterectomy should however be considered when active bleeding occurs from lower uterine segment as the cervical branch of uterine artery may remain intact .
the final decision to perform subtotal or total hysterectomy would be influenced by patient 's condition .
hence , while total abdominal hysterectomy is a more convenient procedure , subtotal eph may be a better choice in certain conditions where surgery needs to be completed in a shorter time .
uterine atony is an indication for eph in 20.6% to 43% of the cases [ 16817 ] .
while this was traditionally the leading cause for eph the incidence has reduced due to the use of newly developed pharmacologic treatment strategies including prostaglandins .
multiparity and oxytocin use for uterine stimulation were found to be the risk factors for uterine atony requiring eph [ 16 ] .
combs et al in their large case control study of patients with post partum hemorrhage reported that pre - eclampsia , nulliparity , twins , induction , prolonged labor and augmentation were all identified as independent risk factors for uterine atony .
the risk factor for this would be multiple previous cesarean sections with a scarred uterus ( figure 1 ) . uterine rupture with life threatening hemorrhage managed by peripartum hysterectomy .
total hysterectomy is the recommended surgical method of eph due to the potential risk of malignancy developing in the cervical stump and the need for regular cytology and other associated problems such as bleeding or discharge associated with the residual cervical stump . currently the proportion of subtotal hysterectomy performed for eph ranges from 53%   to 80% .
the proponents of subtotal hysterectomy report a lesser blood loss , a reduced need for blood transfusion , reduced operating time and reduced intra and postoperative complications .
total hysterectomy should however be considered when active bleeding occurs from lower uterine segment as the cervical branch of uterine artery may remain intact .
the final decision to perform subtotal or total hysterectomy would be influenced by patient 's condition .
hence , while total abdominal hysterectomy is a more convenient procedure , subtotal eph may be a better choice in certain conditions where surgery needs to be completed in a shorter time .
uterine atony is an indication for eph in 20.6% to 43% of the cases [ 16817 ] .
while this was traditionally the leading cause for eph the incidence has reduced due to the use of newly developed pharmacologic treatment strategies including prostaglandins .
multiparity and oxytocin use for uterine stimulation were found to be the risk factors for uterine atony requiring eph [ 16 ] .
combs et al in their large case control study of patients with post partum hemorrhage reported that pre - eclampsia , nulliparity , twins , induction , prolonged labor and augmentation were all identified as independent risk factors for uterine atony .
the risk factor for this would be multiple previous cesarean sections with a scarred uterus ( figure 1 ) .
total hysterectomy is the recommended surgical method of eph due to the potential risk of malignancy developing in the cervical stump and the need for regular cytology and other associated problems such as bleeding or discharge associated with the residual cervical stump . currently the proportion of subtotal hysterectomy performed for eph ranges from 53%   to 80% .
the proponents of subtotal hysterectomy report a lesser blood loss , a reduced need for blood transfusion , reduced operating time and reduced intra and postoperative complications .
total hysterectomy should however be considered when active bleeding occurs from lower uterine segment as the cervical branch of uterine artery may remain intact .
the final decision to perform subtotal or total hysterectomy would be influenced by patient 's condition .
hence , while total abdominal hysterectomy is a more convenient procedure , subtotal eph may be a better choice in certain conditions where surgery needs to be completed in a shorter time .
the complications included blood transfusion ( 88% ) , febrile episodes ( 26.5% ) , perinatal death ( 22.8% ) , bladder injuries ( 8.8% ) , wound infection , dic , ileus , vaginal cuff bleeding and adnexectomy .
the maternal mortality ranged from 0 to 12.5% with a mean of 4.8% [ 168192124 ] .
although no risk assessment system can predict all instances where cesarean delivery will be needed , a significant percentage of the patients who are at high risk for severe hemorrhage and the subsequent need of emergency hysterectomy can be identified before surgery .
the presence of preoperative risk factors should facilitate consultation , referral or transfer of patients before surgery to a tertiary care facility . due to the complexity of the surgery and decision making ,
proper surgical measures such as hemostatic sutures or uterine or hypogastric artery ligation or embolization are options in attempting uterine conservation particularly in patients who are young and in whom future fertility is important and who are relatively haemodynamically stable .
when conservative treatment is not feasible or has failed , prompt eph is performed failing which the delay would contribute to the maternal morbidity and in unfortunate cases mortality .

Answer:
background : peripartum hysterectomy is a major operation and is invariably performed in the presence of life threatening hemorrhage during or immediately after abdominal or vaginal deliveries.material and methods : a medline search was conducted to review the recent relevant articles in english literature on emergency peripartum hysterectomy .
 the incidence , indications , risk factors and outcome of emergency peripartum hysterectomy were reviewed.results:the incidence of emergency peripartum hysterectomy ranged from 0.24 to 8.7 per 1000 deliveries .
 emergency peripartum hysterectomy was found to be more common following cesarean section than vaginal deliveries .
 the predominant indication for emergency peripartum hysterectomy was abnormal placentation ( placenta previa / accreta ) which was noted in 45 to 73.3% , uterine atony in 20.6 to 43% and uterine rupture in 11.4 to 45.5 % .
 the risk factors included previous cesarean section , scarred uterus , multiparity , older age group .
 the maternal morbidity ranged from 26.5 to 31.5% and the mortality from 0 to 12.5% with a mean of 4.8% .
 the decision of performing total or subtotal hysterectomy was influenced by the patient 's condition.conclusion:emergency peripartum hysterectomy is a most demanding obstetric surgery performed in very trying circumstances of life threatening hemorrhage .
 the indication for emergency peripartum hysterectomy in recent years has changed from traditional uterine atony to abnormal placentation .
 antenatal anticipation of the risk factors , involvement of an experienced obstetrician at an early stage of management and a prompt hysterectomy after adequate resuscitation would go a long way in reducing morbidity and mortality .


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 overall annual incidence of intussusception in adults in the general population has been reported to be as low as 2 cases/1 000 000 persons ; adults account for ~5% of confirmed intussusceptions . as high as 90% of cases of adult intussusception
are due to a pathological process , with neoplasms accounting for ~60% of identifiable leadpoints .
one 6-year prospective study encompassing screening of 380 999 computed tomography ( ct ) scan reports that were read as intussusception , 0.04% of cases were in adults . in adults ,
surgery is typically performed owing to the likelihood that a neoplastic or otherwise chronic pathology is the cause of the intussusception .
indications to take any case to the operating room include large caliber of telescoped bowel , long length of telescoped portion , identifiable lead point and evidence of obstruction [ 24 ] .
the former indications owe to the increased likelihood of malignancy requiring surgical exploration and incision , and bowel wall and mesenteric ischemia in the setting of large intussusceptions .
a 61-year - old gentleman presented with a 3-day history of right - greater - than - left lower quadrant abdominal pain , distention , anorexia and one episode of emesis
. the patient also reported only consuming liquids for 57 days prior to presentation as solid foods caused significant discomfort .
three weeks prior , colonoscopic evaluation of his cramping was aborted at 20 cm due to an impassable sigmoid stricture . several hyperplastic polyps and one tubular adenoma
his abdomen was distended and tympanic , with tenderness and fullness appreciated in the right lower quadrant .
1 ) demonstrated small bowel obstruction due to an ileocolic intussusception , from the ileocecal valve to the splenic flexure , and collapsed distal colon .
figure 1:top left : origin ( arrow ) of invagination in the right lower quadrant .
the telescoped bowel contained terminal ileum , cecum , appendix and the entire ascending colon ( fig .
a 4.5 cm  5 cm mass was identified at the lead point , the ileocecal valve .
resection included the right hemi - colon , cecum , appendix and 15 cm of terminal ileum .
a diverting ileostomy was created as well as a mucus fistula for post - operative antegrade colonoscopic evaluation of the remaining colon .

figure 2:left : stills from intraoperative video recording demonstrating the reduction of the intussusception in order to explore the lead point .
right : ischemic terminal ileum ( arrow ) and palpation of the lead point at the ileocecal valve . left : stills from intraoperative video recording demonstrating the reduction of the intussusception in order to explore the lead point .
right : ischemic terminal ileum ( arrow ) and palpation of the lead point at the ileocecal valve .
additional tubulovillous adenomas , tubular adenomas and hyperplastic polyps were identified throughout the excised portion of bowel .
figure 3:low - power ( left ) and high - power ( right ) views of lead point tumor demonstrates > 50% of the tumor composed of pools of mucin ( solid arrow ) , invasive tumor cells ( dotted arrow ) with hyperchromatic chromatin , crowded nuclei , surrounded by pools of mucin [ 57 ] .
low - power ( left ) and high - power ( right ) views of lead point tumor demonstrates > 50% of the tumor composed of pools of mucin ( solid arrow ) , invasive tumor cells ( dotted arrow ) with hyperchromatic chromatin , crowded nuclei , surrounded by pools of mucin [ 57 ] .
this patient 's presentation is exceptionally unique for both the size and cause of intussusception . to our knowledge ,
the few cases we found were always in the setting of malignancy , the patients presented with a similar chronologic progression with escalation of symptoms including liquid - only diets shortly before presentation .
additionally , the very large intussusceptions were always found in the setting of malignancy [ 1012 ] .
it seems that a favorable ( mobile ) anatomy with an indolent process is a common thread amongst these rare cases . further compounding the uniqueness of this case is the lead point tumor 's location and histology , along with the presence of additional terminal ileum and colonic polyps .
the annual incidence in the united states of small bowel adenocarcinoma from 1973 - -2005 is 6.8 cases per 1,000,000 person years , as calculated by surveillance epidemiology and results ( seer ) program .
additionally , ileocecal adenocarcinoma of any type is sparsely described outside of a few case reports [ 8 , 9 , 1315 ] .
mucinous adenocarcinoma tends to be a locally aggressive tumor , and metastasizes by redistribution phenomenon rather than vascular or lymphatic invasion .
presently , we have no unifying diagnosis to correlate the multiple lesions found throughout the telescoped bowel and distal 20 cm of colon and rectum .
however , it is currently estimated that up to 40% of patients with extensive polyps and a positive family history are ruled out for hnpcc by genetic testing for mismatch repair and msi , as was the case for this patient .
nevertheless , the unique presentation of this patient allowed for expeditious removal of a classically aggressive tumor , in what appears to be the first reported case of a long - tract intussusception secondary to a mucinous adenocarcinoma of the ileocecal valve .

Answer:
abstractintussusception in adults lacks specific symptoms and is often diagnosed emergently when they present with obstruction . though intussusception certainly varies in size and location , the increased likelihood of ischemia or obstruction make large intussusceptions very rare in the literature .
 a patient admitted to our facility for small bowel obstruction was found to have extensive intussusception from the right lower quadrant to the splenic flexure , where a lead point was identified .
 histopathology revealed multiple satellite lesions surrounding the lead point tumor , which was found to be invasive mucinous adenocarcinoma of the ileocecal valve .
 while malignancy is found in 60% of lead point identifiable adult intussusceptions , a malignancy is always found in the case of an exceptionally large intussusception .


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 antimetabolite 5-fluorouracil ( fu ) is widely used in the treatment of solid tumors , including gastrointestinal , breast , head , and neck cancers .
cardiotoxicity , a rare adverse effect of 5-fu , has a reported incidence of 1.2% to 18% .
the patient presented with typical angina and electrocardiographic changes suggestive of an ischemic coronary event during the continuous infusion of 5-fu .
the ischemia recurred when the infusion was stopped , and was relieved by administration of nitroglycerin followed by a sublingual calcium channel blocker .
an 83-year - old man who had been diagnosed with stage iiic ( t4n2m0 ) adenocarcinoma of the ascending colon and who had undergone a right hemicolectomy was admitted to inje university seoul paik hospital to begin adjuvant chemotherapy , using the folfox4 regimen ( 400 mg / m 5-fu bolus infusion followed by the continuous infusion of 600 mg / m 5-fu for 22 hours on days 1 and 2 ; 200 mg / m leucovorin as a continuous infusion for 2 hours before 5-fu infusion on days 1 and 2 ; and infusion of 85 mg / m oxaliplatin on day 1 ) .
baseline echocardiography performed 1 month before admission showed normal left ventricular systolic function and no regional wall motion abnormality .
he was treated with 1,500 mg high - dose 5-fu ( 1,000 mg / m ) per day . on the morning of the 3rd day
, he developed a severe , substernal , crushing chest pain during the continuous intravenous infusion of 5-fu ( cumulative dose 1,679 mg / m ) , which was partially relieved by administering sublingual nitroglycerin .
the electrocardiogram ( ecg ) showed st segment elevation with a tall t wave in leads i , avl , and v4 - 6 , and reciprocal st segment depression in leads v1 - 2 ( fig .
the troponin - i and ck - mb levels were 0.010 ng / ml ( reference range ,  0.1 ) and 3.73 ng / ml ( reference range ,  4.94 ) , respectively .
severe hypokinesia of the lateral wall of the left ventricle was noted on a portable bedside echocardiogram .
the 5-fu infusion was stopped , and the chest pain and electrocardiographic changes resolved after intravenous infusion of nitroglycerin at 30 g / min .
emergency coronary angiography was then performed , which revealed significant stenosis in the proximal left circumf lex coronary artery ( lcx ) .
intracoronary nitroglycerin ( 200 g ) was injected to exclude coronary vasospasm , but no change occurred ( fig .
2 ) . intravenous ultrasound ( ivus ) showed severe luminal narrowing with a heavy concentric plaque in the proximal lcx .
percutaneous coronary intervention of the proximal lcx lesion was performed successfully with the implantation of a drug - eluting stent ( 3.5  16 mm ; taxus , national medical center , seoul , korea ) ( fig .
the patient was transferred to the coronary - care unit , where 8 hours later , he reported a recurrence of the anterior chest pain .
the ecg also showed st segment elevation and reciprocal st changes similar to those seen in the previous ischemic events ( fig .
the chest pain and ecg changes persisted despite a 100 g / min nitroglycerin infusion . to rule out acute stent thrombosis ,
the chest pain and ecg changes were relieved after sublingual administration of 10 mg nifedipine . repeated coronary angiography showed a widely patent stent ( fig .
4 ) . the postprocedural troponin - i and ck - mb levels were 0.010 and 4.62 ng / ml , respectively .
echocardiography performed the next day also showed the absence of the regional wall motion abnormality and normal left ventricular systolic function .
we present here a case of severe cardiotoxicity mimicking acute anterolateral myocardial infarction occurring in a patient receiving 5-fu chemotherapy for adenocarcinoma of the colon .
the cessation of 5-fu administration and the subsequent initiation of treatment with a sublingual calcium channel blocker and nitrate resulted in a successful outcome .
although the mechanism by which 5-fu exerts its cardiotoxic effects is unknown , the resolution of the patient 's chest pain and the normalization of his ecg changes with a vasodilator strongly support the vasospastic hypothesis of 5-fu cardiotoxicity .
one study postulated that 5-fu - associated cardiotoxicity is due to the uncoupling of the electromechanical mechanisms that underlie normal myocardial function , which might be mediated at the level of the cell membrane .
recently , kuzel et al .   suggested that 5-fu promotes a hypercoagulable state ( e.g. , coronary artery thrombosis ) and observed a significant increase in fibrinopeptide a and a decrease in protein c activity during 5-fu administration . the incidence of clinically apparent 5-fu cardiotoxicity is less than 10% in patients receiving the drug .
patients with a history of coronary artery disease ( cad ) have a significantly increased risk of 5-fu - induced cardiotoxicity .
although our patient did not have a history of cad , a large atheromatous plaque was found on coronary angiography and ivus .
therefore , during 5-fu infusion , close , careful monitoring of patients , especially those with pre - existing cad or cad risk factors , is mandatory .
prophylactic calcium channel blockers or nitrates should be administered to patients with cad during 5-fu administration , to prevent vasospasm .
one study proposed that impaired renal function is also a risk factor for 5-fu cardiotoxicity .
although it is not clear whether the cardiotoxic metabolites undergo renal excretion , the pathophysiological effect of 5-fu on the myocardium is likely to increase with decreased renal function .
thus it is necessary to clarify which patients may benefit from optimum anti - angina prophylaxis and careful , close monitoring .
the incidence of 5-fu - related cardiotoxicity appears to be dependent on the dosage and delivery system .
infusion of 5-fu , which is now being used more frequently and at higher doses instead of bolus therapy , may be a significant factor in the development of 5-fu cardiotoxicity . in one study ,
nine patients treated with a higher - dose ( > 800 mg / m ) continuous infusion of 5-fu died suddenly . interestingly , despite stopping the 5-fu , the chest pain and ecg changes recurred in our case .
one series reported that 19% of the patients developed reversible angina pectoris during treatment , which lasted for up to 12 hours after cessation of the infusion .
the possible mechanisms of delayed angina are the late release of potent vasoactive 5-fu metabolites , which accumulate over time due to degradation of 5-fu .
therefore , a calcium channel blocker or nitrates should be administered after stopping the 5-fu when 5-fu - induced cardiotoxicity occurs .
the long - term outcome of patients with 5-fu - related cardiotoxicity has not been investigated extensively . as with our case ,
patel et al .   recently reported interval improvements in the left ventricular wall motion abnormalities in echocardiography performed 8 to 15 days following the initial study .
when cardiotoxicity occurs , 5-fu treatment is usually discontinued due to its very high recurrence rate ( 90% )
. the re - administration of 5-fu is not recommended , and a different chemotherapy regimen should be considered .
interestingly , meydan et al .   continued 5-fu chemotherapy in one group who experienced 5-fu cardiotoxicity due to the absence of an alternative drug and found that subsequent serious , hemodynamic consequences were easily controlled with nitrate treatment . for the remaining patients ,
either 5-fu was removed from the combination regimen or an alternative drug was started and no cardiotoxicity developed subsequently . in summary , although 5-fu - associated cardiac toxicity is rare , it may cause angina , myocardial infarction , and even sudden death .
physicians should be aware of this potentially lethal side effect and should start the proper treatment when 5-fu cardiotoxicity develops .
this case supports the vasospastic hypothesis of 5-fu cardiac toxicity , indicating that a calcium channel blocker may be effective for prevention or treatment of 5-fu cardiotoxicity .

Answer:
cardiotoxicity associated with 5-fluorouracil ( fu ) is an uncommon , but potentially lethal , condition .
 the case of an 83-year - old man with colon cancer who developed chest pain during 5-fu infusion is presented .
 the electrocardiogram ( ecg ) showed pronounced st elevation in the lateral leads , and the chest pain was resolved after infusion of nitroglycerin . a coronary angiogram ( cag ) revealed that the patient had significant atherosclerosis in the proximal left circumflex artery .
 coronary artery spasm with fixed stenosis was considered , and a drug - eluting stent was implanted .
 after 8 hours , the patient complained of recurring chest pain , paralleled by st elevation on the ecg .
 the chest pain subsided after administration of intravenous nitroglycerin followed by sublingual nifedipine .
 repeated cag showed patency of the previous stent .
 this case supports the vasospastic hypothesis of 5-fu cardiac toxicity , indicating that a calcium channel blocker may be effective in the prevention or treatment of 5-fu cardiotoxicity .


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:
biological or biopharmaceuticals are drugs produced from living cells through the biological process , and mimic natural biological substances such as hormones .
biosimilars are copy drugs similar to biological drugs that has already been authorized ( the biological reference medicine ) , hence similar but not identical .
indian guidelines define a  similar biologics  as a biological product / drug produced by genetic engineering techniques and claimed to be  similar  in terms of safety , efficacy and quality to a reference biologics , which has been authorized by drug controller general of india ( dcgi ) for safe use in india .
the active substance of biosimilar medicine is similar to one of the biological reference medicine and used in general at the same dosage to treat the same disease .
biosimilars are entity based ( including product - process ) , regulatory based ( under an abbreviated testing ) , and market based ( same manufactures , different trade name ) .
biosimilars also known as similar biological products , follow - up biologics , subsequent entry biological , second entry biological , biogenerics , multisource products , and off - patent biotech products as synonyms .
general public and insurance companies prefer economic alternatives , the long - term economic consequence of using biosimilars have not been studied
biosimilars are a new class of drugs intended to offer comparable safety and efficacy to the reference , off - patent biological .
the active protein structure of biologicals makes them more prone to induce an acute and chronic immune response .
the overall risk is modest with biosimilars , but regulatory pathways are required because of structural complexity , manufacturing process and risk for immunogenicity .
the problems / limitations with biosimilar are that , the two biosimilar have a different origin , the two biosimilars may have same therapeutic effect , may have different side - effects and hence require thorough testing .
the main reason of biosimilar drug development is the expiry of patent protection for many biological medicines [ table 1 ] .
patent expiration of biological / biopharmaceuticals * biopharmaceuticals are different from the conventional small molecule drugs because of the size and complexity of the active substance and nature of the manufacturing process .
even minor change in the process can lead to the fatal outcome ( process is product ) , safety , and efficacy issues .
for epoietin ( erythropoietin ) , minor change in the packaging process caused pure red cell aplasia .
european medicines agency ( emea ) and committee for the medicinal product for human use ( chmp ) raised the objection that marvel insulin and reference human insulin were not comparable .
, withdrew its application as they were unable to meet the standards set by chmp , but biosimilar insulin continues to flood indian market .
hence , legal and regulatory principals applicable to generic drugs can not be applied to biosimilars .
emea - chmp has published product specific guidelines to establish the similarity in terms of safety , efficacy and quality of biosimilar product . according to these guidelines
moreover , in order to support pharmacovigilance monitoring , the specific product given to the patient should be clearly identified .
the active substance of the biosimilar product must be similar in molecular and biological terms to the active substance of the reference medicinal product , and the same reference product throughout the comparability program .
the pharmaceutical form , doses and route of administration of the biosimilar and the reference product should be the same .
if the reference product has more than one indication , the safety and efficacy for all indications have to be justified or demonstrated for each indication separately .
the issue of immunogenicity should always be addressed , and its long - term monitoring is necessary .
fda was given the authority to approve biosimilars , including interchangeable , to maintain safety , efficacy , and quality of biosimilar product .
 abbreviated pathway  for approval of biologics that are  biosimilar  to already approved products .
the abbreviated pathway will eliminate unnecessary and unethical testing of biosimilars in animal and human .
the patient protection and affordable care act of 2010 ( usa ) also supports this .
the new india guidelines  draft guidelines on similar biologics : regulatory requirements for marketing authorization in india ,  were announced in june 2012 , by department of biotechnology ( dbt ) .
the indian guidelines on similar biologics address the pre - marketing and post - marketing regulatory requirement ( i.e. ,  comparability exercise  ) , and also address the requirements related to manufacturing process and quality control .
as such these indian guidelines on similar biologics are comparable in many respects to biosimilar guidelines of usa and eu .
india has adopted a  sequential approach  ( like  stepwise approach  - us and eu ) to market biosimilar products .
the review committee on genetic manipulation of the genetic engineering approval committee ( geac ) with the permission of dcgi , approve clinical trials to be conducted in india related to biosimilar therapeutic products .
the biosimilar has to demonstrate comparable data of non - clinical studies viz . , pharmacokinetics and toxicology ( safety pharmacology , reproduction toxicology , mutagenecity and carcinogenicity ) and clinical studies ( efficacy and tolerability for each indication ) before it gets approval for all indication of the reference medicine .
biosimilars in india consist primarily of vaccine , monoclonal antibodies , recombinant proteins and diagnostics , insulin ( wosulin , insugen , recosulin ) , erythropoietin ( hemax , epofer , wepox , ceriton , epofit ) , hepatitis b vaccine ( shanvac b , revac b , enivac b , biovac b , genevac b , bevac ) , granulocyte colony stimulating factor ( g - csf  grastim , neukine ) , streptokinase ( indikinase , shankinase , stpase ) , interferon alpha-2b ( shanferon ) , rituxinab ( mab ) , epidermal growth factor receptor ( anti - egfr ) ( mab)(reditux , biomab - egfr ) .
status of similar biologics in india there are about 100 biopharmaceutical companies actively involved in research and development , manufacturing and marketing of biosimilar therapeutic products in india .
there were 14 therapeutic drugs ( similar biologics ) available in 50 brands in 2005 ; the number has increased to 20 therapeutic drugs in 250 brands in 2011 .
biosimilar therapeutic products include insulin , erthropoietin , chorionic gonadotropin , streptokinase , interferon and heparin .
the growing biosimilars market offers huge potential for companies involved in manufacturing , research and development .
pharmacovigilance is more important for biosimilar drugs because these are not reference medicine as such , and are from different manufacturer from the reference products .
many adverse effects may appear only after a biosimilar drug is used more extensively , for a longer period of time , in a greater number of patients .
both manufacturers and prescriber should be aware of the importance of post marketing vigilance , and careful on patients taking biosimilar .
biosimilar are not generic ; biologics are larger and more complicated than chemical drugs , due to the complexity of biological / biotechnology derived products the generic approach is scientifically not appropriate for biosimilar products .
the challenge with biosimilars is to know the differences which matter clinically . the specific product given to the patient

Answer:
biologic products are being developed over the past three decades .
 the expiry of patent protection for many biological medicines has led to the development of biosimilars in uk or follow on biologics in usa .
 this article reviews the literature on biosimilar drugs that covers the therapeutic status and regulatory guidelines .
 appraisal of published articles from peer reviewed journals for english language publications , search from pubmed , and guidelines from european medicines agency , us food drug administration ( fda ) and india were used to identify data for review .
 literature suggest that biosimilars are similar biological products , i.e. , comparable but not identical to the reference product , are not generic version of innovator product and do not ensure therapeutic equivalence .
 biosimilars present more challenges than conventional generics and marketing approval is also more complicated . to improve access ,
 us congress passed the biologics price competition and innovation act 2009 and us fda allowed  abbreviated pathway  for their approval .
 u.s law has defined new standards and terms and ema scientific guidelines have also set detailed approval standards .
 india being one of the most preferred manufacturing destinations of biosimilars , there is a need for stringent safety and regulatory guidelines . the new india guidelines  draft guidelines on similar biologics were announced in june 2012 , by department of biotechnology at boston bio and available online .