Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0038454 (stroke)
 147,016 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

alpha 2-Macroglobulin (alpha 2M) was isolated from human plasma by a four-step procedure: poly(ethylene glyco) fractionation, gel chromatography, euglobulin precipitation and immunoadsorption. No contaminants were detected in the final preparations by electrophoresis or immunoprecipitation. The protein ran as a single slow band in gel electrophoresis, and was designated 'S-alpha 2M'. S-alpha 2M bound about 2 mol of trypsin/mol. Treatment of S-alpha 2M with a proteinase or ammonium salts produced a form of the molecule more mobile in electrophoresis, and lacking proteinase-binding activity (F-alpha 2M). The electrophoretic mobility of the F-alpha 2M resulting from reaction with NH4+ salts was identical with that of proteinase complexes. We attribute the change in electrophoretic mobility of the alpha 2M to a conformation change, but there was no evidence of a change in pI or Strokes radius. Electrophoresis of S-alpha 2M in the presence of sodium dodecylsulphate gave results consistent with the view that the alpha 2M molecule is a tetramer of identical subunits, assembled as a non-covalent pair of disulphide-linked dimers. Some of the subunits seemed to be 'nicked' into two-thires-length and one-third-length chains, however. This was not apparent with F-alpha 2M produced by ammonium salts. F-alpha 2M produced by trypsin showed two new bands attributable to cleavage of the subunit polypeptide chain near the middle. Immunoassays of F-alpha 2M gave 'rockets' 12-29% lower than those with S-alpha 2M. The nature of the interactions between subunits in S-alpha 2M and F-alpha 2M was investigated by treating each form with glutaraldehyde before electrophoresis in the presence of sodium dodecyl sulphate. A much greater degree of cross-linking was observed with the F-alpha 2M, indicating that the subunits interact most closely in this form of the molecule. Exposure of S-alpha 2M to 3 M-urea or pH3 resulted in dissociation to the disulphide-bonded half-molecules; these did not show the proteinase-binding activity characteristic of the intact alpha 2M. F-alpha 2M was less easily dissociated than was S-alpha 2M. S-alpha 2M was readily dissociated to the quarter-subunits by mild reduction, with the formation of 3-4 new thiol groups per subunit. Inact reactive alpha 2M could then be regenerated in high yield by reoxidation of the subunits. F-alpha 2M formed by reaction with a proteinase or ammonium salts was not dissociated under the same conditions, although the interchain disulphide bonds were reduced. If the thiol groups of the quarter-subunits of S-alpha 2M were blocked by carboxymethylation, oxidative reassociation did not occur. Nevertheless treatment of these subunits with methylammonium salts or a proteinase caused the reassembly of half-molecules and intact (F-) tetramers. It is emphasized that F-alpha 2M does not have the properties of a denatured form of the protein...
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PMID:The electrophoretically 'slow' and 'fast' forms of the alpha 2-macroglobulin molecule. 9 67

Seven chronically prepared dogs (electromagnetic flow transducers around the pulmonary and left renal artery, left atrial catheter) maintained on a controlled sodium and water intake were studied. About 20 h after the last intake of food and water, the effects of i.v. methohexitone (initial dose: 6.10 +/- 0.84 mg/kg bw; sustaining infusion: 0.34 +/- 0.10 mg/min.kg bw) on renal excretion of sodium, potassium, urea and water as well as on several haemodynamic values were investigated over a period of 60 min (MP) after a control period (CP) of 60 min in the unanaesthetized state. In 18 of 19 experiments water diuresis (U/Posm less than 1) was observed between 20 and 40 min after starting the administration of methohexitone. Urine volume increased from 44 +/- 21 microliter/min.kg bw (CP) to 104 +/- 62 microliter/min.kg bw (MP).I.v. administration of arginine-vasopressin (ADH) completely abolished water diuresis. During MP, there was a decrease in cardiac output (-11%), stroke volume (-36%) and left atrial pressure (-27%), heart rate increased (+ 43%). Mean arterial blood pressure and renal blood flow did not change. It is assumed-as plasma osmolality did not change-that the central release of antidiuretic hormone is suppressed by methohexitone.
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PMID:[Water diuresis during methohexitone anaesthesia. Studies in chronically instrumented dogs (author's transl)]. 65 67

1. Liver nuclei from estrogenized chickens contain high-affinity low-capacity estrogen-binding sites, which are in part salt-extractable (60--70%) and in part tightly sticking to the nuclear residue (30--40%). During the preparation of chromatin with low salt buffers part of the salt-extractable nuclear-binding sites remains together with the non-extractable sites on the chromatin. Extractable and non-extractable sites can be separated by agarose as well as hydroxyapatite chromatography. 2. The extrogen-binding protein extracted from crude nuclei was characterized as follows: sedimentation coefficient of 3.9 S, Strokes' radius (a) of 3.3 nm, molecular weight (Mr) of 56,000 and frictional ratio (f/fo) of 1.20. Trypsination results in a globular receptor fragment (Mr = 41,000), which has lost a small asymmetric portion of the receptor molecule but still binds estradiol. 3. In contrast to the binding protein from crude nuclei the estrogen-binding protein extracted from purified nuclei at pH 7.4 is found mainly in an aggregated form. Dissociation of the aggregates is achieved in high salt/urea resulting in a receptor molecule with an apparent molecular weight of 130,000. Aggregation of the binding sites can be prevented to some extent by raising the pH of the extraction medium. At pH 8.7 the non-aggregated part of the binding protein from pure nuclei could be characterized as follows: 4.4 S, a = 4.3nm, Mr = 80,000 (apparent molecular weight of 150,000), f/fo = 1.40. 4. Mixing experiments indicate that an extranuclear protease present in a crude nuclear preparation converts the large receptor (the binding protein from pure nuclei) to the smaller one (the binding protein from crude nuclei) by digesting off an asymmetric portion of the molecule. This portion seems to be responsible for the strong tendency of the binding protein from pure nuclei to associate with other nuclear components.
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PMID:Estrogen-binding sites of chicken liver. Preliminary characterization of nuclear components. 72 Mar 32

Haemodynamics and renal function have been investigated in 12 patients with valvular heart disease before and after injection of 2 mg bumetanide in the right heart catheter. There were no significant changes in oxygen consumption, arteriovenous oxygen difference, cardiac index, heart beats per minute, stroke volume or right and left ventricular stroke work 35 min after the injection, whereas pulmonary and systemic arteriolar resistance showed a slight but insignificant reduction. Mean pulmonary capillary venous pressure, left ventricular end-diatolic pressure, mean pulmonary arterial pressure and mean pressure in the right atrium were highly significantly reduced after injection, systolic left ventricular pressure showing a significant but slight decrease. The creatinine and urea clearances increased considerably during the first 50 min after injection of bumetanide, but diminished during the second period to levels somewhat lower than the initial values. There was also a marked increase in the clearance of sodium potassium, calcium, magnisium and phosphate. It is concluded that bumetanide is a very potent diuretic which changes haemodynamic parameters towards normal values.
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PMID:Haemodynamics and renal function following injection of bumetanide. 89 69

The effects of hemodialysis on cardiac performance were evaluated by systolic time intervals measured blindly in 15 chronic renal failure patients maintained free of circulatory congestion. After a mean dialysis of 8.7 hours, levels of blood urea nitrogen, serum creatinin, and potassium and body weight showed statistically significant decreases and serum calcium and hematocrit values increased; heart rate and both diastolic and systolic blood pressure did not change significantly. Left ventricular ejection time (LVET) and ejection time index (ETI) were significantly shorter, falling from within normal limits to below normal. Pre-ejection period (PEP) rose significantly. These changes are consistent with a two-fold immediate effect of hemodialysis: (1) reduction of stroke volume as reflected by decreased ETI; and (2) reduced Starling effect, with or without decreased contractility, as reflected by increased PEP.
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PMID:Cardiac effects of hemodialysis: noninvasive monitoring by systolic time intervals. 114 46

Fifteen Marine recruits with acute heat stroke were examined for (1) predisposing factors, (2) blood coagulation disturbances, (3) renal function abnormalities, and (4) blood composition alterations. Epidemiologic data identified the following risk factors; previous residence in a temperate climate, first phase of training, fatigue, and strenuous exercise in hot, humid conditions. Results of blood coagulation studies disclosed an increase in prothrombin and partial thromboplastin times, with a decrease in platelet count, probably indicating a transient, low-grade consumptive process. Blood urea nitrogen and creatinine levels and creatinine clearance were normal. Only mild elevations of SGOT, SGPT, and lactic dehydrogenase levels were noted, and in combination with clinical observations, they argued against significant muscle damage. No deaths or instances of renal failure occurred.
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PMID:Acute heat stroke. Epidemiologic, biochemical, renal, and coagulation studies. 124 74

Thirty-three cases of infective endocarditis presenting during a 6.5 year period to a district general hospital were analysed retrospectively. The annual incidence was 22 cases per million population. Twenty-two cases had pre-existing cardiac disease, mainly valvular disease-usually rheumatic (nine cases) and prosthetic valves (10 cases). Recognizable precipitants such as recent surgery were uncommon. Two cases presented after deliberate drug overdose possibly due to depression exacerbated by systemic disease. Symptoms were usually non-specific. All but two cases had murmurs and most were pyrexial. Splinter haemorrhages and clubbing were seen in about 20% of cases. Viridans-type streptococci were the commonest infecting organisms (14 cases). Staphylococcal infection (six cases) was confined to intravenous drug abusers and patients with prosthetic valves. Five cases were culture negative. Cardiac failure was present in 13 cases at presentation and developed in seven others during treatment. Acute valve replacement was necessary in eight cases, and late replacement in three. Renal impairment (plasma urea > 8 mmol/l and/or plasma creatinine > 120 mumol/l) occurred in 19 cases during the course of their illness. Embolic phenomena occurred in 12 patients and mostly involved the central nervous system. In the 8 fatal cases, the cause of death was cardiac failure in six, cerebrovascular accident in one, and myocardial infarction in one. Four of the six patients who subsequently died of cardiac failure had been referred for surgery. Both those who were not referred had coexisting medical problems. Factors associated with increased mortality were age, male sex, cardiac failure (P < 0.01), renal impairment (P < 0.05), and embolic phenomena (P < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Infective endocarditis in a district general hospital. 143 86

To determine whether hemodynamic advantages of continuous ambulatory peritoneal dialysis (CAPD) over intermittent hemodialysis are associated with improved survival and identify cardiac risk factors for early death, 55 patients on CAPD (age 58 +/- 11 years; CAPD duration: 29 +/- 25 months) were followed in a noninvasive prospective analysis over 35 months. At follow-up, 25 patients had died; 16 deaths were related to cardiovascular causes. Nonsurvivors were older (62 +/- 8 vs 55 +/- 12 years; p less than 0.015) and had more angina pectoris (40 vs 20%; p less than 0.05) than survivors, but had comparable CAPD duration, arterial blood pressure, hemoglobin, serum creatinine, urea and parathyroid hormone concentrations. On echocardiography, nonsurvivors had a lower mean left ventricular (LV) ejection fraction (59 +/- 15 vs 66 +/- 9%; p less than 0.03), higher LV end-systolic volume indexes (49 +/- 31 vs 36 +/- 13 ml/m2; p less than 0.03) and a shorter mean LV ejection time (371 +/- 41 vs 390 +/- 22 ms; p less than 0.03). LV muscle mass, LV diastolic and left atrial dimensions, stroke volume and cardiac index were comparable. On pulsed Doppler analysis of a subgroup of 48 patients in sinus rhythm and without valve disease, nonsurvivors (n = 23) had more severely decreased ratios of peak early/atrial filling velocities (0.66 +/- 0.18 vs 0.81 +/- 0.24; p less than 0.03) and increased atrial filling fractions (52 +/- 11 vs 46 +/- 9%; p less than 0.03) than survivors. Mean isovolumic relaxation periods were increased in both groups (135 +/- 39 vs 129 +/- 33 ms; p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Cardiovascular factors influencing survival in end-stage renal disease treated by continuous ambulatory peritoneal dialysis. 153 Aug 99

The molecular states of collagen in the aortas of age-matched stroke-prone spontaneously hypertensive (SHRSP) and normotensive Wistar Kyoto rats (WKY) were studied by analyzing its extractability under defined conditions. The monomeric and oligomeric collagen extractable with 0.5 M acetic acid/6 M urea from aortic homogenates of 9-month-old SHRSP and WKY comprised approx. 0.6 and 2.0%, respectively, of the total collagen. On incubation of the acetic acid/urea-extracted residues with pepsin at 4 degrees C, the levels of the collagen alpha 1(I) and alpha 2(I) chains solubilized from the SHRSP residues were both less than 50% of those from the WKY residues. When the residues were incubated with pepsin at 15 or 25 degrees C, the differences became smaller. When the acetic acid/urea residues were hydrolyzed with cyanogen bromide, nearly identical peptide maps were obtained for SHRSP and WKY. The aortas from 2-month-old SHRSP and WKY contained much larger proportions of acid/urea-extractable collagen than those of the older rats (8.2 and 13% of the respective total collagen). The levels of the alpha 1(I) and alpha 2(I) chains solubilizable from the respective residues by pepsin at 4 degrees C were similar to each other. These results indicate that aortic collagen fibrils in SHRSP are stiffened more prominently than those in WKY.
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PMID:Comparative studies on the extractability of collagen from aortas of stroke-prone spontaneously hypertensive and normotensive rats. 161 Sep 9

Postoperative mortality and morbidity of diabetic versus nondiabetic patients undergoing primary coronary artery bypass grafting (CABG) were analyzed. In 1988, 711 patients had CABG procedures, of which 565 were nondiabetic and 146 diabetic. The two groups of patients were statistically similar in regard to age, weight, tobacco and ethanol use, and preoperative levels of cholesterol, triglycerides, blood urea nitrogen (BUN), and creatinine. Preoperative serum glucose levels were significantly elevated in diabetic patients (182 vs. 106, P less than .001). Cardiac output, ejection fraction, and bypass, crossclamp time, and total operating room times were not different for the two groups. Emergent and urgent procedures had a significantly higher mortality rate than elective cases (11.3% and 6.6% vs. 1.7%, respectively; P less than 0.05), but this was independent of the patient's diabetic status. Women had a higher mortality rate than men (6.5% vs. 2.9%; P = 0.05) although within each gender group, there were no differences between diabetics and nondiabetics. There were 27 patients with complications in the diabetic group (18.5%) and 47 in the nondiabetic group (8.3%; P less than .001). The types of complications within the two groups differed in that wound infections (7.5%), postoperative arrhythmias (4.8%), respiratory failure (4.1%), and intra-aortic balloon pump use (4.1%) were significantly greater (P less than .05) in the diabetic patients compared to the nondiabetic (0.9%, 1.8%, 0.4%, and 1.4%, respectively). Occurrences of postoperative pneumothorax, reoperation, myocardial infarction, stroke, urinary tract infection, and pneumonia were similar in both groups.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Complications of coronary artery surgery in diabetic patients. 192 97


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