shukoor65/lab-rag-model huggingface dataset:
Aortic dissection resulting from tear of transverse arch: is concomitant arch repair warranted? Forty-seven patients with aortic dissection resulting from a primary tear located in the transverse aortic arch underwent surgical treatment. Twenty-six patients had acute type A, 7 had acute type B, 7 had chronic type A, and 7 had chronic type B aortic dissections. Of the 33 patients with acute dissections, 11 (7 acute type A and 4 acute type B) underwent concomitant arch repair with an operative (less than or equal to 30 days) mortality rate of 55% (35% to 73%, +/- 1 asymmetric 70% confidence limit) (2 of 7 acute type A and 4 of 4 acute type B). Concomitant arch repair was omitted in 22 patients with acute dissections (19 acute type A and 3 acute type B); the operative mortality rate was 41% (29% to 54%) (7 of 19 acute type A and 2 of 3 acute type B) (p = not significant versus arch repair). The overall survival rate for those with arch repair was 45% +/- 15% (+/- 1 standard error of the estimate) at 4 years, compared with 43% +/- 11% for patients without arch repair (p = not significant). Considering the type of dissection, the 4-year survival estimate for patients with acute type A dissections who underwent arch repair (5 hemiarch and 2 total arch) was 71% +/- 17% (versus 44% +/- 12% for acute type A patients without arch repair). There were no survivors among the 4 patients with acute type B dissections who had an arch repair (1 hemiarch and 3 total arch), whereas patients with acute type B dissections who did not undergo concomitant arch repair had a 4-year survival estimate of 33% +/- 27% (p = not significant versus arch repair). Four other patients with acute type B dissections resulting from an arch tear were managed medically and tended to have a slightly better prognosis (2-year survival estimate of 75% +/- 22% versus 14% +/- 13% for all surgically treated acute type B patients), but again this difference was not statistically significant. Multivariate analysis of the 47 surgical patients revealed that advanced age (p = 0.0008), preoperative dissection complications (p = 0.02), and other coexistent medical problems (p = 0.03) were the only significant, independent determinants of overall mortality. Initial arch repair was not a significant predictor. Nine percent (2/22) of patients with acute type A dissections who initially underwent isolated ascending aortic replacement required subsequent arch replacement; 1 died after reoperation.(ABSTRACT TRUNCATED AT 400 WORDS).
The eosinophilia-myalgia syndrome: the Los Alamos Conference. On June 12 and 13, 1990 the Los Alamos National Laboratory in cooperation with the New Mexico Department of Health and Environment, the Centers for Disease Control (CDC), the Food and Drug Administration (FDA), and the National Institute of Arthritis and Musculoskeletal and Skin Diseases of the National Institutes of Health (NIH) hosted a conference on the eosinophilia-myalgia syndrome. Fifty presentations covered a variety of important issues which are summarized herein.
Interleukin-7 differentiates a subgroup of acute lymphoblastic leukemias. The bone marrow stromal cell-derived growth factor interleukin-7 (IL-7) is known to stimulate growth of normal human B-cell precursors. In the present report, we have examined the effect of IL-7 on neoplastic B-cell precursors. Leukemic cells from 20 patients with common acute lymphoblastic leukemia (ALL) were highly purified by removing contaminating T cells and monocytes by rosetting with immunomagnetic beads. IL-7 markedly reduced the DNA synthesis in leukemic cells from three patients. This inhibition of DNA synthesis was accompanied by maturation of the cells, as demonstrated by the induced expression of the differentiation antigens CD19, CD20, CDw75, and surface mu-chain, and a decreased expression of terminal deoxynucleotidyl transferase. By examining G1 parameters, such as MYC, 4F2, and transferrin-receptor levels analyzed by flow cytometry as well as RNA and the cell cycle regulated antigen Ki67, it appeared that the cells were inhibited late in G1. Leukemic cells from the majority of the cases (12 of the 20 patients) responded to IL-7 with enhanced DNA synthesis without detectable maturation, as has been reported for their normal counterparts. Low molecular weight B-cell growth factor greatly potentiated the IL-7-induced growth stimulation of these cells. Thus, we have shown that IL-7 is capable of inhibiting proliferation of leukemic cells isolated from a subgroup of ALLs, and that this growth inhibition is accompanied by maturation of the cells.
Magnesium inhibits the hypertensive but not the cardiotonic actions of low-dose epinephrine. Intravenous magnesium supplementation is often used to control cardiac arrhythmias and coronary artery vasospasm resulting from disturbances of magnesium homeostasis after coronary artery bypass surgery. Many such patients also require inotropic drug support of depressed myocardial function. However, increased serum magnesium concentrations directly depress cardiac contractility in animals and may interfere with catecholamine actions. To determine whether small intravenous doses of magnesium sulfate (MgSO4) interfere with the cardiotonic actions of epinephrine, we examined the hemodynamic effects of MgSO4 and epinephrine infusion in 17 cardiac surgical patients on their 1st postoperative day in a prospective, controlled study. In 11 patients, infusion of MgSO4 (7-mg.kg-1 bolus followed by 10 mg.kg-1.h-1 as a continuous infusion) increased serum magnesium concentrations by 44% (mean +/- standard error of the mean [SEM] of 0.8 +/- 0.1 to 1.2 +/- 0.1 mM; P less than 0.01) but had no significant effect on heart rate; mean arterial, central venous, or pulmonary arterial occlusion pressures; or cardiac output. Epinephrine infusion (30 ng.kg-1.min-1) significantly increased cardiac index (2.7 +/- 0.1 to 3.1 +/- 0.21.min-1.m-2; P less than 0.05); this effect was not altered by MgSO4 administration (n = 11). However, MgSO4 significantly blunted epinephrine's hypertensive action and prevented a significant increase in mean arterial pressure during concurrent MgSO4-epinephrine administration. Six placebo control patients were given two sequential infusions of epinephrine separated by a placebo infusion to rule out an effect of time on the hemodynamic response to epinephrine. Mean arterial pressure and cardiac index responses to epinephrine were identical before and after placebo infusion.
Diagnostic importance of the radiographic density of noncalcified breast masses: analysis of 91 lesions. Radiographic density is considered an important feature in the evaluation of noncalcified breast masses, yet no studies assessing its value have been published. The radiographic densities of 91 biopsy-proved, nonfatty, noncalcified breast masses were evaluated by three mammographers. The density determinations made by each observer were compared with the histologic outcome for the 51 benign and 40 malignant lesions. With the kappa statistic, interobserver agreement was relatively poor (0.22 to 0.49), and intraobserver agreement for one expert mammographer was 0.50. When the majority opinion of the mammographers was used, sensitivity was 48%, specificity was 80%, and both positive and negative predictive values were 66%. As a solitary feature in lesion analysis, mammographic density is difficult to assess and is of limited value for the prediction of the benign or malignant nature of noncalcified breast masses.
Retrograde suction decompression of an ophthalmic artery aneurysm using balloon occlusion. Technical note. A large ophthalmic artery aneurysm was ligated using a modification of the retrograde suction technique described by Batjer and Samson. Temporary proximal occlusion of the internal carotid artery was accomplished with a double-lumen balloon catheter, and distal occlusion was performed with a temporary clip. The aneurysm was collapsed by gentle aspiration through the distal lumen of the balloon catheter. This greatly facilitated dissection and clip ligation of the aneurysm.
Patterns in visual interpretation of coronary arteriograms as detected by quantitative coronary arteriography. In part 1 of a three-part study, 14 novice readers and 6 experienced cardiologists interpreted phantom images of known stenosis severity. No difference between the interpretations of experienced and novice readers was detectable. Visual estimates of "moderately" severe stenosis were 30% higher than actual percent diameter stenosis. In part 2 of the study, visual interpretation of percent diameter stenosis from 212 stenoses on 241 arteriograms was compared with quantitative coronary arteriographic assessment. The visual analysis overestimated disease severity in arteries with greater than or equal to 50% diameter stenosis (except for right coronary lesions) and underestimated severity in all arteries with less than 50% diameter stenosis. Of the 241 arteriograms, 40 had quantitative and visual analysis of all three coronary arteries for assessment of significant disease. In only 62% of the cases did visual and quantitative methods agree on the presence of severe disease; visual estimates diagnosed significantly (p less than 0.05) more three-vessel disease. In part 3 of the study, comparison of percent diameter stenosis by visual estimate with quantitative coronary arteriographic assessment before and after balloon angioplasty of 38 stenoses showed that visual interpretation significantly (p less than 0.001) overestimated initial lesion severity and underestimated stenosis severity after angioplasty.
Headache syndromes as detected by configural frequency analysis. Data on headache symptoms obtained in two samples (N = 422 and 304) by means of questionnaires were subjected to configural frequency analysis (CFA). This not widely-known method tests whether certain symptom combinations appear more often or less often than expected by chance. In both samples symptom combinations corresponding to the syndromes of migraine with aura, migraine without aura and tension headache did indeed occur with significant frequency. The same clear-cut symptom patterns appeared when patients with preceding visual disturbances were excluded from analysis. These results seem to lend strong support to a categorical model of headache, rather than to the concept of headache as a spectrum.
Phenytoin-induced hemocytophagic histiocytosis indistinguishable from malignant histiocytosis. We have reported a case of phenytoin-induced hemocytophagic histiocytosis indistinguishable on clinical and histopathologic grounds from malignant histiocytosis. We emphasize the need to investigate for microbiologic causes and drug ingestion, even if the diagnosis of malignant histiocytosis is plausible. We think that reactive and malignant histiocytosis are not really two distinct entities with different etiologies, but a continuum of host responses to several insults with different degrees of aggressiveness depending on the host immune status.
Radiologic findings of clonorchiasis. Clonorchiasis is a trematodiasis caused by chronic infestation of liver flukes, Clonorchis sinensis. The adult flukes reside in the medium-sized and small intrahepatic bile ducts and, occasionally, in the extrahepatic bile ducts, gallbladder, and pancreatic duct. The result is mechanical obstruction, inflammatory reaction, adenomatous hyperplasia, and periductal fibrosis. Signs and symptoms are usually mild and nonspecific, but heavy infestation results in obstructive jaundice. The disease has a close relationship with recurrent pyogenic cholangitis and cholangiocarcinoma. In this article, the radiologic findings, including cholangiography, sonography, and CT of clonorchiasis are reviewed in light of the pathophysiology of the disease. The relationship to recurrent pyogenic cholangitis and to cholangiocarcinoma is discussed.
An immunoinhibitory cell wall glycoprotein (mannan) from Trichophyton rubrum. Trichophyton rubrum causes 90% of chronic dermatophyte infections. Most patients with widespread chronic T. rubrum infection fail to express a delayed hypersensitivity reaction to intradermally injected trichophytin. We propose that cell-mediated immunity to T. rubrum may be suppressed in chronic infections by the mannan cell wall component of the fungus. The proposed suppressive effect of T. rubrum mannan on cell-mediated immunity was tested by measuring the ability of extracted mannan to inhibit lymphoproliferative responses of human mononuclear leukocytes to antigens, mitogens, and an anti-T-cell receptor antibody (anti-CD3) in vitro. Mannan was found to be highly antigenic in two of five donors and weakly antigenic in the other three. Despite its antigenic property, mannan exhibited a dose-related ability to inhibit lymphoproliferation stimulated by other agents including 1) antigens from Candida albicans, T. rubrum, and tetanus toxoid (ID50 = 250 micrograms/ml); 2) anti-CD3 antibody (ID50 = 250 micrograms/ml); and 3) Phaseolus limensis mitogenic lectin (ID50 = 64 micrograms/ml). Mannan added to cultures later than 24 h after initiation had no inhibitory influence, but culture of cells with mannan for a period of 24 h prior to the addition of stimulus enhanced the inhibitory effect of the glycoprotein. Lymphoproliferation in response to recombinant interleukin-2 (IL-2) was not inhibited. The influence of time of addition of mannan and the failure of mannan to inhibit IL-2-stimulated lymphoproliferation demonstrate that the suppressive effect of mannan must be pharmacologic rather than cytotoxic. The observed ability of T. rubrum cell wall mannan to suppress cell-mediated immune function in vitro may provide an important clue to a mechanism enabling the fungus to avoid elimination in chronically infected patients.
Polycystic kidneys, pancreatic cysts, and cystadenomatous bile ducts in the oral-facial-digital syndrome type I. Oral-facial-digital syndrome type I is a group of X-linked dominant conditions, lethal in utero in male individuals. Internal anomalies are less well documented than are external findings. We report a case of typical phenotype and absent family history of kidney disease in a 15-year-old white girl (46,XX) who died of renal failure and massive cerebral hemorrhage. At necropsy, the kidneys were greatly enlarged but of fairly normal shape. The cortex was replaced by thin-walled spherical cysts, 0.5 to 2.0 cm in diameter; the majority of the smaller cysts were located deep in the cortex, and the medulla contained lesser numbers of larger cysts. No distal urinary tract obstruction was present. Microdissection revealed cysts and diverticula located in all segments of the nephrons and collecting ducts. Uninvolved nephrons showed diffuse hypertrophy. These findings were correlated with immunoperoxidase stains using peanut lectin, Lotus tetragonolobus agglutinin, antibodies to cytokeratins, stage-specific embryonic antigen-1, Tamm-Horsfall protein, and epithelial membrane antigen. Other visceral anomalies included biliary cystadenomatous proliferation in the liver and pancreatic cysts. The renal changes are similar to those of autosomal dominant (adult-type) polycystic disease.
Effect of the tibial cut on subsidence following total knee arthroplasty. In 33 total knee arthroplasties (TKAs) using instrumentation designed to cut the tibia with 0 degree posterior slope, ten tibial components demonstrated at least 2 mm of tibial component subsidence. These subsided components were implanted onto tibiae with an average of 8 degrees +/- 2 degrees difference between the preoperative, anatomic posterior slope and their postoperative posterior slope. The remaining 23 components, without subsidence, were implanted onto tibiae cut within 2 degrees +/- 2 degrees of their anatomic slope. To help understand these clinical observations, a laboratory study was performed to compare the load carrying capacity and the stiffness of tibial subchondral bone following two types of tibial cuts: one made perpendicular to the long axis of the tibia and the other made parallel to the articular surface of the tibia. Mock tibial baseplates mounted on paired cadaver tibiae were loaded in compression and force displacement curves were recorded. Tibiae cut parallel to the surface exhibited 40% greater load carrying capacity and 70% greater stiffness than the paired tibiae cut perpendicular to the long axis. The biomechanical data of this study indicated that cutting the tibia perpendicular to the long axis results in weaker bone that may be inadequate to support a tibial component. This may explain the higher incidence of clinical subsidence if the tibial cut is not made approximately parallel to the anatomic slope.
Finapres: a noninvasive device to monitor blood pressure. Often, obstetric patients are not evaluated in preliminary studies during the development of new medical devices. The purpose of this study was to compare the Finapres digital probe with oscillometric and arterial line devices for recording blood pressures in low- and high-risk pregnant women. A total of 38 women were studied, including 24 with pregnancy-induced hypertension, two with chronic hypertension, two with cardiac disease, and ten who had no risk factors but requested epidural catheter placement. The comparison of Finapres or oscillometric recordings with direct arterial values confirmed that systolic recordings were imprecise for both devices (r = 0.80 and r = 0.64, respectively). Diastolic recordings (Korotkoff sound, phase 4) from the Finapres were accurate compared with the arterial values (r = 0.84). The Finapres performed at least as reliably as the oscillometric monitor in assessing blood pressure in our pregnant population and provided continuous measurements. When very accurate systolic recordings are needed, arterial catheter placement may be necessary.
Some perspectives on peptic ulcer. In this article, the author comments on the following topics: whether peptic ulcer is a disease or just the sign of another process; whether the crater has a multifactorial origin; the ubiquity of Helicobacter pylori and the conclusion that a specific strain will doubtless prove to be the cause of some, but not all, ulcers; the inherent definitional problem of "nonulcer dyspepsia"; and the controversy over how much gastric acid needs to be reduced to speed the healing of peptic ulcer.
Hepatocyte proliferation in stepwise development of experimental liver cell cancer. Cell proliferation is the most central and key phenotypic property of cancer including hepatocellular carcinoma. Hepatocyte proliferation is central not only at the late steps in carcinogenesis, the cancer, but at the earliest known step, initiation. Compensatory or regenerative hepatocyte proliferation is essential to initiation with chemical carcinogens but primary hyperplasia is ineffective. During promotion, hepatocyte proliferation is the major change seen as clonal proliferation to generate nodules occurs. During progression, autonomous hepatocyte proliferation balanced by cell loss makes its appearance. This continues in a balanced fashion with only a slight excess of proliferation over loss until the earlier steps in malignancy at which time the balance is disrupted.
Splenosis: an unusual cause of intraabdominal hemorrhage. A 31-year-old female presented to the emergency department with an acute onset of severe abdominal pain. She developed hypovolemic shock from an intra-abdominal bleed. At laparotomy she was found to be bleeding from two areas of splenosis on the uterine ligament. The patient had sustained a ruptured spleen 22 years prior and had no symptomatology from her areas of splenosis. A short review of splenosis is presented.
Streptokinase and recombinant tissue plasminogen activator (rt-PA) are equally effective in treating acute myocardial infarction. In recent trials, patients with myocardial infarction who received either recombinant tissue-type plasminogen activator (rt-PA) or streptokinase showed essentially no difference in the amount of myocardial salvage, in mortality reduction, or in the incidence of bleeding complications. These findings thus failed to fulfill the expectation that rt-PA would be twice as effective as streptokinase as a thrombolytic agent. The basis for this mistaken prediction was an unfortunate overemphasis on an inadequate surrogate endpoint, namely, the patency or reperfusion rate at 90 minutes after the start of therapy. Using the 90-minute patency or reperfusion rate as an endpoint has several serious limitations. First, it is an observation made at only one point in time during a dynamic process that may change even during the infusion proper. Second, a single view at 90 minutes completely disregards the possibility of subsequent reocclusion which often occurs within 1 hour after treatment. Third, an image at 90 minutes is more a reflection of the speed of thrombolysis than of whether lysis will eventually occur; the pace of clot lysis depends on both the agent used and the age of the thrombus. Fourth, lysis at 90 minutes is of minimal relevance for myocardial salvage unless observed within the time frame when infarction size can be limited significantly, which is generally less than 4 hours between symptom onset and the time that reperfusion is accomplished. Fifth, a stable state of vessel patency is meaningful for mortality reduction even if stabilization occurs after completion of the infarction. Such "late," but lasting, patency is a critical component of the "open vessel" principle and explains, at least in part, the survival benefit that accrues to patients treated even 24 hours after the onset of symptoms. There is currently no evidence that rt-PA has a more beneficial effect on survival or function than does streptokinase or any other plasminogen activator used in treating acute myocardial infarction; nor is there any evidence that patients who receive rt-PA therapy show a decreased incidence of bleeding complications compared with those who receive streptokinase, despite the relative fibrinogen-sparing attribute of rt-PA. Given the poor predictive value of the 90-minute angiogram for ultimate clinical advantage of one agent over another, studies that are limited to this endpoint are of marginal use in evaluating treatment regimens used in mortality studies. The best evidence to date indicates that streptokinase and rt-PA are of equivalent value for survival after acute myocardial infarction, a conclusion that can be justifiably challenged only with a valid mortality study.
Successful transcatheter embolization of pseudoaneurysm associated with pancreatic pseudocyst. Hemorrhage into a pancreatic pseudocyst is a rare event, but is the most rapidly lethal complication of chronic pancreatitis. Visceral-vessel aneurysms are an unexpectedly common finding in arteriography of patients with chronic pancreatitis. This case report describes bleeding from an anterior superior pancreaticoduodenal artery aneurysm, caused by chronic pancreatitis. The aneurysm was successfully treated by embolization with a steel coil.
Concealed rhythms by double ventricular parasystole. Electrocardiograms taken from 11 patients in sinus rhythm with ventricular ectopic rhythms from two different foci were analyzed to find the number of sinus beats, S, between the ectopic rhythms (S values). Three out of 11 patients had the S values typical for concealed ectopic rhythms. One of them had concealed bigeminy of 2n-1 form that occasionally shifted to 2n form. Following the shift, S values of 2n-1 form were always achieved by the occurrence of double ventricular ectopic rhythms in succession. Concealed trigeminy of 3n and 3n-2 form was seen in the other two patients. Double ventricular ectopic rhythms had bizarre abnormal QRS complexes of two different morphologies and were inscribed in opposite directions. Ectopic rhythms in each case had parasystolic characteristics. These observations suggest bifocal automaticity as a mechanism for bidirectional ventricular tachycardia.