shukoor65/lab-rag-model huggingface dataset:
Doppler estimation of changes in pulmonary artery pressure during hypoxic breathing. To assess the use of Doppler echocardiographic screening for abnormal pulmonary vasoreactivity, we measured pulmonary artery pressure in 10 adult patients and 11 normal subjects while recording Doppler right ventricular outflow acceleration time, pre-ejection period, and ejection time. In the normal subjects we also measured the changes in each parameter after 10 minutes of hypoxic breathing (FIO2 = 0.12). Mean pulmonary artery pressure increased by 39% during hypoxia (13 +/- 4.3 to 18 +/- 5.4 mm Hg). In the patients and normal subjects at rest, mean pulmonary artery-pressure correlated well with acceleration time (r = -0.84; standard error of the estimate, 6.6 mm Hg; p = 0.0001). Over the narrow range of mean pulmonary artery pressure in normal subjects at rest, mean pulmonary artery pressure did not correlate well with acceleration time, acceleration time/pre-ejection period, or acceleration time/right ventricular ejection time. However, changes in mean pulmonary artery pressure induced by hypoxic breathing did correlate with changes in acceleration time/right ventricular ejection time (r = 0.73; standard error of the estimate, 2.3 mm Hg; p = 0.01). Doppler ultrasound may offer a noninvasive means for detecting abnormal pulmonary vasoreactivity in asymptomatic individuals at risk for developing pulmonary hypertension.
Laparoscopic trancystic choledocholithotomy as an adjunct to laparoscopic cholecystectomy. Laparoscopic cholecystectomy is rapidly becoming the standard operation for symptomatic cholelithiasis. Initially, common duct stones presented a barrier to this treatment modality and are said to be unsuspected in 5-9 per cent of patients. A technique is described that removes common bile duct stones through the cystic duct with a flexible nephroureteroscope, thereby extending the range of laparoscopic cholecystectomy.
Hepatocellular carcinoma. A worldwide problem and the major risk factors. Male sex, age, cirrhosis, and HBsAg are the major risk factors for hepatocellular carcinoma (HCC). The geographic distribution of HCC is highly uneven, such that three distinct incidence areas are recognized. To clarify the reason(s) for this geographic variability of HCC, the risk factors in each incidence area were assessed. In parallel with the geographic distribution of HCC, HBsAg prevalence was highest in both HCC patients and in general population in Africa and Asia, where mothers of HCC patients are frequently HBsAg-positive, suggesting that hepatitis B virus hyperendemicity and perinatal infection account for the high HCC incidence in these areas. Cirrhosis, which is found on autopsy in 80% of the cases of HCC patients worldwide, is the most prevalent risk factor for HCC in areas where hepatitis B virus infection is less common. However, HBsAg carriage adds to the HCC risk carried by cirrhosis and explains the higher incidence of HCC in cirrhotics from Africa and Asia as well as elsewhere. Available data suggest that chronic HCV infection is a risk factor for cirrhosis and HCC. HBV vaccination should decrease HCC incidence rates worldwide; however, HCC prevention in regions where HBsAg carriage is infrequent may also require prevention of the other causes of cirrhosis in order for HCC rates to decline.
Linkage analysis of juvenile parkinsonism to tyrosine hydroxylase gene locus on chromosome 11. We performed linkage analyses of juvenile parkinsonism with autosomal recessive inheritance (AR-JP) to chromosome 11p15.5 locus including tyrosine hydroxylase (TH), Harvey-ras-1 (HRAS), and insulin (INS) genes by analyzing genomic DNA from 28 members of seven Japanese AR-JP families containing 10 affected individuals. We used the methods of pairwise linkage analysis (LIPED) and multipoint linkage analysis (LINKAGE) for genetic linkage to the chromosome 11p15.5 markers and detected recombination events between AR-JP locus and TH gene. Multipoint linkage analysis excluded the linkage in the interval between TH and HRAS, as well as 11 cMo distal to TH and 8.5 cMo distal to HRAS, a total of approximately 23 cMo on chromosome 11p.
Usefulness of leg-crossing for maintaining blood pressure in a sitting position in patients with orthostatic hypotension--case reports. The authors report a case with idiopathic orthostatic hypotension in which the patient prevents his blood pressure from falling to a symptomatic level by leg-crossing in a sitting position. Including 4 other patients with orthostatic hypotension and 5 normal subjects, their study found that the changes in blood pressure with leg-crossing inversely correlated with those induced by assuming seated posture from a supine position. Leg-crossing may, therefore, be one of the useful nonpharmacologic measures for maintaining blood pressure in a sitting position in patients with orthostatic hypotension.
Intratumoral T lymphocytes from small cleaved follicular center cell lymphomas show unrestricted T-cell receptor alpha-chain variable region gene usage. The relationship between the reactive T cells and neoplastic B cells of follicular center cell lymphomas is unclear. It is not known whether the T cells are recruited nonspecifically by the neoplastic B cells or are responding through the T-cell antigen receptor (TCR), to tumor-related antigen(s). This question was addressed by polymerase chain reaction analysis of TCR alpha chain variable (V) region gene expression in intratumoral T lymphocytes from three cases of small cleaved follicular center cell lymphoma. In all three cases studied, the tumor-associated T cells showed unrestricted expression of all 18 alpha-chain V region genes. These findings imply that the T cells admixed with the neoplastic B cells of small cleaved follicular center cell lymphomas are not recruited based on TCR recognition of a single or limited number of tumor-related antigens.
Mechanisms and management of stroke in the elderly. OBJECTIVE: To highlight the mechanisms, common causes and management of stroke in the elderly. DATA SOURCES: MEDLINE was searched for articles published from 1967 to 1990. The following key words were used: "stroke," "cerebrovascular disease," "elderly," "aging," "hypertension," "drug interactions," "etiology," "evaluation," "management" and "recovery of function." Original articles with large series of patients were reviewed in detail. STUDY SELECTION: Of about 750 original articles reviewed 116 were finally selected for detailed analysis. Those that dealt with cause, pathophysiologic features and management of stroke with emphasis on the elderly were chosen. DATA SYNTHESIS: With increasing age the incidence of stroke increases, cardiovascular reserve decreases, catecholamine responsiveness diminishes and cardiac arrhythmias become more common. Blood pressure, especially systolic, rises, and the benefits of its treatment become both more difficult to assess and less certain. In the elderly population embolic stroke, particularly that due to nonvalvular atrial fibrillation, is seen with increasing frequency. Because of postural hypotension, cardiac arrhythmias and overmedication, watershed infarction occurs more frequently with increasing age. Amyloid angiopathy now represents the most common cause of spontaneous intracerebral hemorrhage. CONCLUSIONS: Because of the altered drug metabolism and pharmacodynamics in the elderly the therapeutic armamentarium is growing, and so are the risks of such treatments. Stroke in the elderly poses unique problems that deserve distinctive solutions. Further research is needed to study the effect of cerebral ischemia to understand better how the older brain handles the stress of the ischemic insult.
Gastro-oesophageal reflux in mechanically ventilated preterm infants. Long duration oesophageal pH recordings were performed on 42 mechanically ventilated and parenterally fed preterm infants for a mean (SD) of 94 (28) hours. Their mean (SD) gestational age was 31.5 (2.6) weeks and birth weight 1514 (448) g. Their mean postnatal age was 19 (10) hours at the onset of pH recording, which was performed with the babies supine. The mean hourly values for the total number of episodes of gastro-oesophageal reflux (GOR) was 2.3 (2.7), for acid GOR 1.2 (1.4), and for acid GOR longer than 5 minutes 0.08 (0.09). The time the pH was greater than 4 (the reflux index) was 3.5 (3.3)% and the mean airway pressure was 6.6 (5.1) cm H2O. Fifteen infants had a reflux index above 5%. GOR patterns were not significantly correlated to birth weight, gestational age, postconceptional age, ventilatory patterns, and duration of mechanical ventilation. We concluded that the reproducibility of the reflux index was low because the median of the absolute differences was 1% when two consecutive 12 hour periods were compared and reached 2.5% when the two periods were separated by 96 hours. A second 24 hour pH recording was performed in 30 of the 42 patients after weaning from the ventilator and at a time when patients were asymptomatic and enterally fed. Compared with the late postprandial period of the second pH recording, the first recording showed an increase in the number of episodes of GOR and a decrease in reflux index, without any difference in the number of episodes of acid GOR.
Transsphenoidal management of Rathke's cleft cysts. A clinicopathological review of 10 cases. We report detailed data on 10 patients who underwent transsphenoidal microsurgical management of histopathologically confirmed Rathke's cleft cysts. Preoperatively, pituitary dysfunction was present in 90%, headaches in 80%, hyperprolactinemia in 70%, and visual interference in 40%. Computed tomography and magnetic resonance imaging had 90% and 100% sensitivity, respectively, in disclosing the lesion. The mean follow-up duration was 22 months. There was no mortality. The only morbidity was sustained diabetes insipidus in one case. Resolution or improvement in preoperative dysfunction occurred in the majority of patients: headaches in 100%, visual deficits in 75%, normalization of hyperprolactinemia in 83%, and reversal of panhypopituitarism in 33%. We conclude that Rathke's cleft cysts can be managed safely and effectively with transsphenoidal drainage and partial excision of the wall.
Correlation of technetium-99m-DISIDA hepatobiliary studies with biopsies in liver transplant patients. We compared 76 99mTc-DISIDA hepatobiliary studies with corresponding liver biopsies in 36 liver transplant patients to determine the histopathologic abnormalities that corresponded to scintigraphic abnormalities in uptake and excretion. Uptake was judged normal if the cardiac blood pool was barely visible or invisible on the ten minute image. Excretion was judged normal if images subsequent to the 15-min image showed a subjectively normal rate of decreasing parenchymal intensity. Biopsies were graded subjectively for hepatocyte damage and for findings of cholestasis. Uptake criteria were successful in differentiating high from low hepatocyte damage scores (p less than 0.0001), and excretion criteria were successful in differentiating high from low cholestasis scores (p = 0.002), while uptake criteria were not capable of differentiating high from low cholestasis scores, nor were excretion criteria capable of differentiating high from low hepatocyte damage scores (p's greater than 0.05). These results suggest that scintigraphy can distinguish intrahepatic cholestasis from pure hepatocyte damage.
Psychologic factors associated with peptic ulcer disease. Peptic ulcer disease provides an excellent model for the study of mind-body interactions in the pathogenesis and course of an illness. Early psychodynamic explanations of the role of personality factors in the evolution of peptic ulcer disease have been supplemented in recent years by more scientifically based studies on the role of stress and coping ability. Multiple psychosocial variables have confounded the outcome of many of these studies. Yet, a clear need and guidelines exist for the comprehensive medical and psychosocial evaluation and treatment of patients with peptic ulcer disease. Concomitant psychiatric assessment and management, including psychotherapeutic and psychopharmacologic approaches, for those patients with refractory symptoms or ongoing psychiatric symptoms carried out in close collaboration with primary caregivers will significantly decrease overall morbidity and mortality.
The preferential antagonism of pentylenetetrazole proconflict responses differentiates a class of anxiolytic benzodiazepines with potential antipanic action. With the use of the shock-induced suppression of water drinking in thirsty rats (Vogel's conflict paradigm) and the pentylenetetrazole-enhanced shock-induced suppression of drinking (proconflict paradigm) as animal models to test anxiolytic and antipanic agents, it was possible to distinguish two major classes of benzodiazepines (BZDs) and congeners on the basis of their antiproconflict index (ratio of anticonflict/antiproconflict potencies). Thus, typical low potency BZDs and congeners (diazepam, midazolam, zolpidem, alpidem) with anxiolytic/hypnotic properties have a low antiproconflict index (close to 1), whereas typical high potency BZDs (clonazepam, alprazolam, bretazenil) with reported antipanic properties have an antiproconflict index approximately 10-fold higher. The anticonflict and antiproconflict actions of BZDs with low or high antiproconflict indices are blocked by flumazenil but are potentiated differentially by the gamma-aminobutyric acid (GABA) reuptake blocker 1-2-[bis(trifluoromethyl)-phenyl]-methoxyethyl-1,2,5,6-tetrahydro-3- pyridine-carboxylic acid. Protracted administration of antianxiety and antipanic antidepressant drugs that do not act on GABAA receptors, directly, resulted in anticonflict and antiproconflict effects. However, the efficacy of these drugs is clearly inferior (20-30%) to that of BZDs. These data suggest that specific GABAA receptor subtypes mediate the pharmacological action of BZDs possessing low and high antiproconflict indices.
Early loss of astrocytes in herpes simplex virus-induced central nervous system demyelination. Immunohistochemistry was used to study herpes simplex virus type 1-induced central nervous system demyelination in the trigeminal root entry zone of mice inoculated with herpes simplex virus type 1 by the corneal route. There was no change in peripheral nervous system myelin as shown by immunostaining for Po glycoprotein. Double immunoperoxidase staining for herpes simplex virus type 1 antigens and glial fibrillary acidic protein showed that most of the infected cells were astrocytes. Glial fibrillary acidic protein immunostaining was completely lost in the inferior medial portion of the trigeminal root entry zone at 6 days after herpes simplex virus type 1 inoculation, a time when central nervous system myelin was preserved as indicated by immunostaining for myelin basic protein. The pattern of glial fibrillary acidic protein staining did not change and herpes simplex virus type 1 antigens were no longer detected after day 8. There was a progressive loss of myelin basic protein staining within the area unstained by glial fibrillary acidic protein antisera on days 8 to 14. This pattern of astrocyte loss before central nervous system demyelination is strikingly different from the reactive astrocytosis seen in other demyelinating lesions, such as acute experimental allergic encephalomyelitis, progressive multifocal leukoencephalopathy, or acute multiple sclerosis. Herpes simplex virus type 1 infection in mice provides an unusual model of acute central nervous system demyelination preceded by a loss of astrocytes.
Cerebrovascular CO2 reactivity during delayed vasospasm in a canine model of subarachnoid hemorrhage. While the in vitro reactivity of cerebral conducting vessels following subarachnoid hemorrhage has been extensively studied, in vivo cerebrovascular CO2 reactivity has not been systematically investigated. We tested the hypothesis that, in the canine model of subarachnoid hemorrhage, the rise in cerebral blood flow normally seen with hypercapnia is blunted during delayed vasospasm. Four groups of animals were studied: one received two 4-ml subarachnoid injections of nonheparinized arterial blood into the cisterna magna (n = 8), one received three subarachnoid injections of 5 ml blood (n = 5), one received two subarachnoid injections of 4 ml saline (n = 5), and a control group (n = 5) had no subarachnoid injections or angiography. Basilar artery diameter was measured from baseline and follow-up angiography. We determined CO2 reactivity by randomly varying the concentration of inspired CO2 and measuring regional cerebral blood flow with radiolabeled microspheres. Basilar artery diameter was not affected by saline injection and was reduced by 26 +/- 2.9% in the two-hemorrhage group and 55 +/- 1.9% in the three-hemorrhage group. Baseline cerebral blood flow and CO2 reactivity were similar in all four groups. We conclude that, in this model of delayed vasospasm, regional cerebral vascular CO2 reactivity is intact and extrapolation of in vitro data regarding basilar artery diameter and reactivity to cerebral blood flow must be done cautiously.
ABO blood groups and the risk of diarrhea due to enterotoxigenic Escherichia coli. To determine whether blood group O persons are at higher risk for enterotoxigenic Escherichia coli (ETEC) diarrhea, a case-control study was done for 17 months among rural Bangladeshis who were under systematic surveillance for diarrhea. Cases were children less than 3 years old who presented between 1 January 1985 and 1 June 1986 for care of heat labile (LT) or heat stabile toxin-producing ETEC diarrhea. Controls were of similar ages and were randomly selected from three community-based serosurveys between July 1985 and May 1986. No association between blood group O and ETEC diarrhea was found for the 510 cases and 641 controls, nor was an association evident for cases of each toxin phenotype. Further refinement of the case definition to include only patients with LT-ETEC diarrhea, without enteric copathogens, also failed to reveal a substantial association with blood group O. These data suggest that a strong association with ABO groups, analogous to that for cholera, does not exist for ETEC diarrhea.
Alleged brain damage, diminished capacity, mens rea, and misuse of medical concepts. As focus on the insanity defense diminishes, defendants may place emphasis on a lack of knowing or purposeful behavior in order to negate a criminal charge. This use of a mens rea defense in accord with Model Penal Code principles is exemplified by the current New Jersey statute. Such a defense may result in a lesser charge or a finding of not guilty. In addition to reviewing applicable law, this report presents a sex offense case in which remote brain damage was invoked as a purported basis for incapacity to formulate the required intent; the study also raises the issue of the inappropriate or questionable use of medical principles, a practice that diminishes professional credibility in the courts and in the community.
Regulation of Ras-GAP and the neurofibromatosis-1 gene product by eicosanoids. Ras-GAP (GTPase activating protein) is a regulatory protein that stimulates the intrinsic guanosine triphosphatase (GTPase) activity of the proto-oncogene product p21ras. A domain of the neurofibromatosis gene product (NF1) that has sequence similarity to the catalytic domain of Ras-GAP and to yeast IRA gene products also has a specific stimulatory activity toward p21ras GTPase. Arachidonic acid and phosphatidic acid inactivate GAP, but no agents have been identified that stimulate GAP and thereby switch p21ras off. With the use of recombinant Ha-c-Ras and Ras-GAP, NF1, and GAP catalytic domains, it was found that prostaglandins PGF2 alpha and PGA2 stimulated Ras-GAP and that prostacyclin PGI2 inhibited Ras-GAP. The stimulatory effect of PGF2 alpha was saturable and structure-specific and competed with the inhibitory effect of arachidonic acid. Arachidonic acid also inhibited the catalytic activity of NF1, but prostaglandins were not stimulatory. These results suggest a mechanism for the allosteric control of Ras function through the modulation of arachidonate metabolism.
Treatment of male genital condylomatous lesions by carbon dioxide laser after failure of previous nonlaser methods. Carbon dioxide laser was used to treat 119 male patients with condylomata acuminata after other treatments had failed. In 82.3% of the patients, the treatment resulted in complete disappearance of the lesions, whereas in the others two to three treatments were required. Advantages of the laser treatment are discussed.
Effects of quinapril, a new angiotensin converting enzyme inhibitor, on left ventricular failure and survival in the cardiomyopathic hamster. Hemodynamic, morphological, and biochemical correlates. The effect of chronic therapy with quinapril on the temporal progression of left ventricular failure and survival was assessed in the CHF 146 cardiomyopathic (CM) hamster, which is an idiopathic model of congestive heart failure. Age-matched Golden Syrian (GS) hamsters served as normal controls. Quinapril was administered in the drinking water at average daily doses of 10.2, 112.4, and 222.4 mg/kg/day. In untreated CM hamsters, in vitro left ventricular performance progressively deteriorated with increasing age beginning at roughly 180 days. This decline in left ventricular performance was accompanied by a decrease in coronary flow and an increase in left ventricular volume. Administration of quinapril from 180 to 300 days of age prevented the decline of in vitro left ventricular contractile performance and coronary flow and also reduced the age-dependent increases in left ventricular volume. The cardioprotective effects of quinapril were observed at doses of 112.4 and 222.4 mg/kg/day but not at 10.2 mg/kg/day. Lung angiotensin converting enzyme activity was significantly inhibited by quinapril in GS and CM hamsters at 240 and 300 days of age at all dose levels. In contrast, significant inhibition of ventricular angiotensin converting enzyme activity was observed consistently at doses of 112.4 and 222.4 mg/kg/day quinapril but not at 10.2 mg/kg/day. In the survival protocol, CM and GS hamsters were treated with vehicle or quinapril (100 mg/kg/day) from 180 to 522 days of age. During the initial 210 days of treatment (from 180 to 390 days of age) 78.3% of the vehicle-treated CM hamsters died compared with 27.7% of quinapril-treated CM hamsters. Quinapril increased the median survival time of CM hamsters by 32.9% (112 days). It is concluded that chronic quinapril therapy exerts a significant cardioprotective effect and also increases survival.
Two-point fixation of the lumbar spine. Differential stability in rotation. Single vertebral motion segments were tested in torsion. The adjacent vertebrae were transfixed by two 3-mm Steinman pins placed vertically. These were applied in five different positions: between the anterior vertebral bodies, posterior vertebral bodies, pedicles, transverse processes, and lamina. Rotational displacement was limited the most by transfixation between the vertebral bodies (position one or two). Disrupting the anulus fibrosus significantly increased rotation in all positions except those in the vertebral body. These findings may imply that spinal fixation devices that engage the vertebral bodies may offer inherent advantages over purely posterior devices in stabilizing a vertebral motion segment. In addition, an interbody arthrodesis may prevent intervertebral motion better than a posterior or posterolateral fusion.