123rc/medical_text huggingface dataset:
The role of prostanoids in the production of acute acalculous cholecystitis by platelet-activating factor. Gallbladder tissue from patients with acute acalculous cholecystitis contains increased amounts of prostanoids when compared to normal gallbladder tissue. Platelet-activating factor (PAF) is a potent stimulus of eicosanoid formation. It has been implicated as a mediator of acute inflammatory processes and systemic responses to shock. In this study the role of PAF in acute acalculous cholecystitis was evaluated. Anesthetized cats underwent gallbladder perfusion with a physiologic buffer solution containing [14C]polyethylene glycol as a nonabsorbable tracer to quantitate mucosal water absorption. Platelet-activating factor was infused into the hepatic artery for 2 hours. Control experiments were performed when vehicle alone was infused. Experiments also were performed when indomethacin was administered intravenously and when indomethacin and PAF were administered. Gallbladder mucosal absorption/secretion and perfusate and tissue prostaglandin E (PGE) and 6 keto prostaglandin F1 alpha (6-keto PGF1 alpha) levels were evaluated. Gallbladder inflammation was evaluated by beta-glucuronidase and myeloperoxidase tissue concentrations and by a histologic scoring system. Platelet-activating factor eliminated gallbladder absorption and produced net fluid secretion associated with dose-related increases in perfusate PGE concentrations and gallbladder tissue PGE and 6 keto PGF1 alpha levels when compared to control values. Platelet-activating factor produced significant inflammation in the gallbladder with increases in the histologic score of inflammation and tissue lysosomal enzyme activities. Indomethacin significantly decreased the fluid secretion, prostanoid levels, and inflammation produced by PAF. The results suggest that PAF may induce acute gallbladder inflammation associated with systemic stress through a prostanoid-mediated mechanism.
Primary treatment of large and massive adult sarcomas with iododeoxyuridine and aggressive hyperfractionated irradiation. For a decade, the authors have experimented with treatment for unresectable adult soft tissue and bony sarcomas. Over the last 6 years, they have combined hyperfractionated radiation therapy and intravenous iododeoxyuridine as a radiosensitizer, in regimens designed to minimize toxicity and permit delivery of aggressive radiation therapy. Patients with solitary lesions and those with metastasis (38%) were treated in the hope of both potential cure in some and durable palliation in others. The most formidable of these cancers have been those that are large or massive, often requiring five or more fields and extensive treatment planning. The authors report results from 36 patients with large unresectable sarcomas (tumors ranging from 5 to 35 cm; average 14 cm) treated with hyperfractionated radiation therapy, with a minimum follow-up of 1 year, follow-up of 4 or more years (in 50%), or follow-up until death. Overall local control has been 60%, with control of 66% of lesions from 5 to 9 cm, 63% of those from 10 to 14 cm, 63% of those from 15 to 19 cm, and 57% of those greater than 20 to 40 cm. Morbidity has been modest. This experience compares favorably with the authors' earlier trials with misonidazole, and toxicity has been reduced considerably.
Temporal relation between left ventricular dysfunction and chest pain in coronary artery disease during activities of daily living. Forty-three ambulatory patients with angina of increasing frequency underwent continuous monitoring of left ventricular (LV) function for an average of 2.9 +/- 1.9 hours to determine the incidence and temporal sequence of LV dysfunction, ST-segment depression and chest pain. Indicators of ischemia were: a decrease in ejection fraction greater than 5% lasting greater than 1 minute; horizontal or downsloping ST-segment depression of greater than or equal to 1 mm; or onset of the patient's typical chest pain complex, or a combination of these. During the monitoring interval, subjects performed daily activities such as sitting, walking, climbing stairs and eating. In 11 patients, 22 episodes of chest pain or ST-segment depression, or both, were observed. Eighteen episodes were accompanied by a decrease in ejection fraction (9 patients); chest pain accompanied the decrease in ejection fraction during 13 episodes, whereas ST-segment changes occurred during 7. In 12 of 13 episodes the decrease in ejection fraction began earlier than the onset of chest pain, whereas in 1 patient ejection fraction decrease and chest pain onset started at the same time. The average interval from a decrease in ejection fraction to the onset of chest pain was 56 +/- 41 seconds (range 0 to 120). ST changes occurred after the onset of a decrease in ejection fraction in 6 of 7 episodes. The average interval from the onset of ejection fraction decrease and the onset of ST change was 99 +/- 91 seconds. These data suggest that LV dysfunction manifested by a decrease in ejection fraction is an earlier indicator of myocardial ischemia than is angina pectoris or electrocardiographic evidence of ischemia.
Could Wallerian degeneration contribute to "leuko-araiosis" in subjects free of any vascular disorder? To determine the possible role of Wallerian degeneration secondary to the grey matter neuronal loss in the pathogenesis of "leuko-araiosis", computerised tomography (CT) of the brain was studied in 98 normotensive and non diabetic subjects free of cardiac diseases: 32 with Alzheimer's disease, 36 with Parkinson's disease, eight with progressive supranuclear palsy, and 22 controls. In Alzheimer's disease, leuko-araiosis scores were greater than in control subjects. Leuko-araiosis was more prominent in anterior periventricular areas in Parkinson's disease and progressive supranuclear palsy, and in posterior periventricular areas in Alzheimer's disease. In two patients with Alzheimer's disease and leuko-araiosis, necropsy revealed diffuse white matter pallor, mild fibrillary astrocytosis, and in one patient limited hyaline thickening of small white matter vessels, without any infarction or hypertensive change. Changes were more severe in white matter close to cortical areas with a great density of neurofibrillary tangles. Leuko-araiosis was more severe or more widespread in Alzheimer's disease than in Parkinson's disease, progressive supranuclear palsy and normal ageing. Differences in the location of leuko-araiosis between the four groups might be due to differences in the location of the grey matter disorder and Wallerian degeneration rather than amyloid in Alzheimer's disease, Parkinson's disease, progressive supranuclear palsy and normal ageing. Wallerian degeneration might be another cause of leuko-araiosis in neuro-degenerative disorders beside previously reported extra-cerebral predisposing factors and amyloid angiopathy.
Effect of dipyridamole (Persantin) on blood flow and patency of aortocoronary vein bypass grafts. The effect of dipyridamole was investigated in 360 patients undergoing coronary bypass surgery. They were randomly allocated to receive dipyridamole (100 mg orally q.i.d. for 2 days preoperatively, 5 mg/kg body weight/24 h i.v. peroperatively and 100 mg orally q.i.d. for 1 year postoperatively) or placebo. Withdrawn from the study were 48 patients on dipyridamole and 57 on placebo. Cardiovascular and/or cerebrovascular events or need for anticoagulant treatment were the reasons for withdrawal in 22 (13%) of the dipyridamole, and 34 (18%) of the placebo group. Logistic regression analysis of risk factors influencing graft patency showed significant relation to peroperatively measured coronary blood flow. A positive trend of treatment was observed (p = 0.08). Vein graft blood flow measured during bypass surgery (245 patients) was significantly greater in the dipyridamole group (p less than 0.01). The occlusion rate was lower in vessels with peroperative blood flow greater than 30 ml/min (vein-marginal p less than 0.01, vein-dexter p less than 0.05, vein-diagonal 0.05 less than p less than 0.1). Dipyridamole increases coronary blood flow and graft patency following coronary bypass surgery.
Effect of emitted power on waveform intensity in transcranial Doppler This study assesses the problem of transcranial Doppler recording failure and seeks to determine the extent to which this can be ameliorated by increased emitted power. We hypothesized that waveform intensity is directly related to the rate and quality of successful recording and may be compared quantitatively among groups of patients. Among a large group of patients recorded at 800 mW/cm2 emitted power, intensity was strongest in white men, weakest in black women, and intermediate in black men and white women. It declined with age in women of either race, but not in men of either race. Analysis of the effect of emitted power on intensity predicted that significant numbers of waveforms recorded at 800 mW/cm2 could not be recorded at the current clinical standards of 100 mW/cm2, the difference being most pronounced in elderly black women. Temporal bone window thickness measured in a series of adult cadaver skulls was least in white men, greatest in black women, and intermediate in black men and white women. The findings of this study support the hypothesis that temporal bone window thickness is an important determinant of recording difficulty and suggest that increased emitted power can significantly increase successful recording, particularly in black and elderly patients. Increased power alone, however, cannot completely solve the recording problem within safe limits.
Significance of the number of stimuli to initiate ouabain-induced arrhythmias in the intact heart. Ouabain-induced arrhythmias are a well-known model used to study triggered activity resulting from delayed afterdepolarizations. In the intact heart, initiation of these arrhythmias is promoted by pacing, especially at fast rates. However, the relevance of the number of stimuli is unknown. In conscious dogs with formalin-induced atrioventricular block, we investigated the effect of variations in pacing mode on 1) the behavior of nonsustained triggered rhythms at progressive levels of ouabain intoxication, and 2) the induction of sustained ventricular tachycardia (VT). Twenty experiments were analyzed. Ouabain was administered as a bolus of 40 micrograms/kg followed by continuous infusion. Every 15 minutes the pacing protocol was repeated, with a maximum of 10, until completion or induction of VT. When VT could not be initiated, the experiment was repeated at least 1 week later, adding 5-10 micrograms/kg ouabain to the bolus and increasing the infusion rate correspondingly. This was repeated until VT could be induced. Four interstimulus intervals (200, 400, 600, and 800 msec) and seven numbers of stimuli (5, 10, 20, 35, 50, 100, and 150) were given in two pacing protocols. The effect of these protocols on 1) the number of induced beats per stimulation train, 2) their first postpacing interval, and 3) induction of VT were studied. Initiation of VT occurred after 75 +/- 42 minutes. The bolus of ouabain needed to induce VT was inversely related to the body weight of the animals. Progression of ouabain intoxication resulted in 1) a significant increase in the number of induced beats per stimulation train and 2) a significant shortening of the first postpacing interval. Stimulation at a faster rate and/or more stimuli resulted in 1) a significantly pronounced increase in the number of induced beats at the higher levels and 2) a significantly shorter first postpacing interval at successive levels of ouabain intoxication.
Endoscopic variceal ligation in patients who have failed endoscopic sclerotherapy. Endoscopic variceal ligation has been developed as an alternative to endoscopic sclerotherapy. We report a series of 12 men with a history of bleeding esophageal varices who were treated with endoscopic variceal ligation after they had failed sclerotherapy. Hemostasis was achieved in all 10 patients who were bleeding at the time of initial endoscopy and again in those who subsequently re-bled. Over a follow-up period of up to 22 months, varices have been and remain eradicated in five patients; in four others, a reduction in grade was noted before death (two patients), liver transplant, or loss to follow-up (one patient each); two patients died before they could be re-evaluated, while in the remaining patient, no reduction in variceal grade was noted before loss to follow-up. No complication was recorded after 35 endoscopic treatment sessions involving a total of 245 rubber band ligations. Our results indicate that endoscopic variceal ligation may be used with success in patients who fail sclerotherapy.
Endoscopic treatment of biliary tract strictures in sclerosing cholangitis: a larger series and recommendations for treatment. We report a group of 35 patients with primary sclerosing cholangitis who had long-term follow-up after endoscopic treatment of major ductal strictures in the primary or secondary biliary ducts. Our patients were all symptomatic with ascending cholangitis or jaundice. There was significant improvement as measured by clinical parameters of hospitalization rates and laboratory data and comparable radiography. Long-term follow-up averaged 24 (+/- 2.8 months). We believe endoscopic treatment of sclerosing cholangitis should be attempted in selected symptomatic cases with major ductal strictures before liver transplantation.
Does auxiliary heterotopic liver transplantation reverse hypersplenism and portal hypertension? In this study, performed to assess the effect of auxiliary heterotopic liver transplantation on portal hypertension and hypersplenism, eight patients with chronic liver disease who underwent the procedure and had functioning grafts for at least 6 months were analyzed. The transplantation resulted in (a) normalization of platelet and leukocyte counts, (b) reduction of splenomegaly by 20% +/- 3% (P less than 0.02), (c) disappearance of ascites, and (d) diminution of esophageal varices in all patients. Intraoperatively, the mean portacaval pressure gradient decreased with 54% +/- 7% after recirculation of the graft (P less than 0.05). In conclusion, a functioning auxiliary heterotopic liver graft decompresses portal hypertension and reverses hypersplenism.
Multipolar electrocoagulation versus injection therapy in the treatment of bleeding peptic ulcers. A prospective, randomized trial. This study prospectively compares multipolar electrocoagulation and injection therapy in high-risk patients with bleeding ulcers. Patients were considered for entry if they had a bloody nasogastric aspirate, melena, or hematochezia and unstable vital signs, transfusion of greater than or equal to 2 U of blood in 12 hours, or a decrease in hematocrit of greater than or equal to 6% in 12 hours. Sixty patients with endoscopic evidence of an ulcer with active bleeding (n = 26) or a nonbleeding visible vessel (n = 34) were randomly assigned to receive multipolar electrocoagulation or injection with absolute ethanol. Hemostasis was achieved in 14 of 14 actively bleeding patients with multipolar electrocoagulation vs. 10 of 12 (83%) treated with injection. No significant differences were observed between electrocoagulation and injection therapy in any parameter assessed during the hospitalization: incidence of further bleeding (6% vs. 10%), units of blood transfused after treatment (1.8 +/- 0.6 vs. 1.3 +/- 0.4), incidence of surgery for bleeding (6% vs. 7%), length of hospital stay in days (5.8 +/- 0.9 vs. 7.2 +/- 2.5), cost of hospitalization (+7160 +/- +1630 vs. +8520 +/- +2960), or mortality rate (3% vs. 3%). Treatment induced bleeding in nonbleeding visible vessels in 35% of subjects in each group, but this was controlled with continued treatment in all patients. One delayed perforation occurred 9 days after multipolar electrocoagulation. Multipolar electrocoagulation and injection therapy are of comparable efficacy in the treatment of patients with clinical evidence of a major upper gastrointestinal bleed and endoscopic evidence of an ulcer with active bleeding or a nonbleeding visible vessel.
Experimental cardiac tamponade: correlation of pressure, flow velocity, and echocardiographic changes. Seven episodes of experimental cardiac tamponade were induced in five anesthetized closed-chest dogs. Simultaneous pericardial and intracavitary pressures were synchronized with superior vena caval and transvalvular pulsed-Doppler flow tracings. The earliest indication of tamponade was the development of a negative transmural right atrial pressure that occurred during early ventricular diastole and was associated with echocardiographic evidence of right atrial collapse. This was also associated with reversal of diastolic flow in the superior vena cava and with diminished early diastolic flow velocity across the tricuspid as well as the mitral valve. During more advanced cardiac tamponade, the transmural right atrial pressure became negative during both early and late ventricular diastole as well as during isovolumic ventricular systole. This was associated with a disappearance of early diastolic ventricular filling and right ventricular diastolic collapse as observed on two-dimensional echocardiography. In hypotensive cardiac tamponade (cardiac output diminished by 70%), the decreased transmural right atrial pressure that developed during ventricular systole was accompanied by diminished antegrade flow in the superior vena cava. In advanced and hypotensive tamponade, ventricular filling occurred mainly during atrial contraction.
Long-term 6-mercaptopurine treatment in adolescents with Crohn's disease Although 6-mercaptopurine is often used to treat adolescents with intractable Crohn's disease, its long-term efficacy has not yet been studied in this population. This study shows data derived from 36 adolescents (mean age +/- SD, 16.5 +/- 3.3 years; 27 males, 9 females) treated at least 6 months with 6-mercaptopurine (1.5 mg.kg-1.day-1, maximum of 75 mg/day). Sites of Crohn's disease at the start of 6-mercaptopurine therapy included 17 ileocolic, 9 pancolic, 7 small bowel, and 3 partial colon. All had received corticosteroids, sulfasalazine, antibiotics, and nutritional support for 5.0 +/- 3.0 years before administering 6-mercaptopurine, but intractable symptoms persisted. Disease activity lessened during the first year of 6-mercaptopurine, reflected by a higher Lloyd-Still disease activity score (pre, 64 +/- 9 vs. 6-mercaptopurine, 72 +/- 11; P less than 0.0001). General activity, physical examination, nutrition, and laboratory subscores all improved (P less than 0.004). Lessened disease activity occurred despite concomitant decrease in duration of prednisone use (pre, 9.5 +/- 4.2 vs. 6-mercaptopurine, 6.6 +/- 4.9 months/year; P less than 0.001) and cumulative annual prednisone exposure (pre, 3672 +/- 2106 vs. 6-mercaptopurine, 1964 +/- 1460 mg; P less than 0.0007). The frequency of perianal fistulae and abscesses also decreased (P less than 0.01) during treatment. Annual rates of hospitalization decreased in 44% of subjects during 6-mercaptopurine treatment, while increasing in only 22%. Follow-up beyond 1 year of 6-mercaptopurine treatment showed continued remission in 23 of 30 subjects. No serious complications were seen. 6-mercaptopurine is an effective long-term therapy for adolescents with intractable Crohn's disease. While inducing remission, it also has a significant steroid-sparing effect which may be of particular benefit to this population.
Goal attainment scaling and outcome measurement in postacute brain injury rehabilitation. Relationships among two-month and final goal attainment scaling (GAS) scores, preadmission and final Portland Adaptability Inventory (PAI) scores, and work outcome for 16 graduates of a comprehensive, postacute brain injury rehabilitation program were examined. Final GAS scores were higher for program graduates who obtained the most desirable work outcomes, and preadmission and final PAI scores were lower for the successful program graduates. Final GAS scores were significantly correlated with other outcome measures. Preadmission PAI scores predicted work outcome, and two-month GAS scores predicted final GAS scores. Initial PAI scores distinguished between program successes and failures, but not between program successes and dropouts. A brief look at one case illustrates the modified application of GAS in postacute brain injury rehabilitation. Results of this study and case analyses support GAS as a quantifiable, individualized measure that is useful for (1) monitoring patient progress, (2) structuring team conferences, (3) ongoing rehabilitation planning and decision-making, (4) concise, relevant communication to family, referral sources, and funding sources, and (5) overall program evaluation when used in the context of other objective outcome measures. Although our results support the clinical utility of GAS, further study is recommended to assess the psychometric characteristics of GAS in this application.
Long-term follow-up in patients with incessant ventricular tachycardia. Seventeen patients with coronary artery disease, idiopathic dilated cardiomyopathy or no organic heart disease who presented with incessant ventricular tachycardia (VT) were studied and followed for a mean period of 51 +/- 35 months. In these patients the incessant VT included greater than or equal to 3 episodes of sustained VT at a rate of greater than or equal to 120 beats/min and frequent episodes of nonsustained VT over a 24-hour period. No patient had electrolyte disorder, prolonged QT interval, drug-induced arrhythmia or myocardial infarction less than 2 weeks old. Six patients died within 27 months of follow-up; 4 from sudden death and 2 from acute myocardial infarction. Three of the 11 surviving patients had remission of their VT within 1 week after the diagnosis of incessant VT. In 3 other patients in whom antiarrhythmic drugs were discontinued during follow-up because of adverse effects of the drugs or other medical reasons, 2 were found in remission. In the remaining 5 alive patients, deliberate attempts were made to discontinue the antiarrhythmic drugs; 4 of these patients were found in remission when the drugs were discontinued. Thus, 9 of these patients (53%) with incessant VT had remission over a mean follow-up of 55 +/- 34 months after discontinuation of the antiarrhythmic drugs. The probability of remission in patients surviving incessant VT warrants trials of discontinuation of antiarrhythmic drugs in these patients.
Lymph node metastasis in spindle cell carcinoma arising in odontogenic cyst. Report of a case. The majority of primary intraosseous carcinomas of the jaws develop in preexisting odontogenic cysts. These tumors are usually well-differentiated keratinizing carcinomas with relatively good prognosis. Only two of 41 previously reported acceptable cases of primary intraosseous carcinomas from ex-odontogenic cysts were associated with cervical lymph node metastasis. Spindle cell carcinoma is an anaplastic dimorphic neoplasm with poor prognosis. It has a special predilection for the upper aerodigestive tract. This is to our knowledge the first report of spindle cell carcinoma developing in an odontogenic cyst. Cervical lymph node metastasis showing typical histologic features of spindle cell carcinoma was detected 8 months postoperatively. The prognostic implications of this finding are discussed in light of previously reported cases of intraosseous carcinoma arising in odontogenic cysts and of spindle cell carcinoma of the oral cavity.