Biomedical subjects
Publications and source records attributed to S Wagner.
We describe surgical and maintenance procedures for the "double-fistula" preparation in rat. Rats are prepared with esophageal fistulas, so that material swallowed escapes from an opening in the throat; and with gastric cannulas that permit both nutritional and hydrational maintenance, and the experimental intubation of fluids directly into the stomach.
In rats that are food- but not water-deprived, a saccharin "meal" is characterized by a progressive decrease in lap rate as the bout progresses. However, saccharin does not trigger a fixed rate of lapping at any point in the sequence. When rats have only intermittent access to saccharin early in the session, they increase their rates of lapping so that, within each few minutes, the amount of lapping (or some correlate such as volume drunk) is held constant. This happens over a wide range of restriction conditions. And if compensation cannot occur during a period of constraint, then it occurs afterward, promptly and precisely. When constraint is withdrawn, rats drink amounts such that the total amount of drinking (or its correlate), through that point in the ingestive bout, is defended. These findings imply that the controlling system includes (1) an integrator that keeps track of the amount of drinking that has occurred, even across interruptions; and (2) a short-term feedback loop that operates minute by minute within the bout. This loop regulates, not the rate of lapping to be emitted, but the amount of lapping to be done (or its correlate); Thus the decline in responsiveness to saccharin as drinking progresses reflects a depression of this regulated value, not of lap rate per se.
The turtle urinary bladder serves as a model for collecting duct functions in the mammalian kidney. The epithelium of both the turtle bladder and the mammalian collecting duct can generate a steep gradient for H+ ions between blood and urine. Secretion of H+ into the urine is coupled to a basolateral efflux of HCO-3 that appears to be exchanged mainly against Cl-. Here we show that approximately 80% of the dark cells of the bladder contain a 110,000 relative molecular weight (Mr) analogue of the turtle erythrocyte anion exchanger, band 3. The band 3 analogue is confined to the basolateral cell surface and is absent from the apical membrane. A minor population of the dark cells (approximately 20%), which have been previously suggested to represent reverse cells that are involved in HCO-3 secretion rather than absorption, appears not to express a band 3-like anion exchanger, at either the apical or the basolateral membrane. The bladder band 3 protein is colocalized with actin and isoforms of ankyrin (200,000 Mr) and spectrin (230,000 Mr) along the basolateral membrane. Linkage of band 3 via ankyrin to the spectrin-actin lattice may restrict this anion exchanger to the basolateral membrane surface. In view of our previous observation of a band 3-like anion exchanger in the collecting duct epithelium of the rat kidney, these findings point to a common molecular basis for acid-base transport in the mammalian collecting duct and the reptilian urinary bladder.
Poly- and monoclonal antibodies have been prepared against the cytoplasmic domain (43 kDa) and the 17-, 20-, and 35-kDa fragments of the membrane-spanning domain of the human erythrocyte anion exchanger, band 3. The antibodies were used to localize and further characterize analogues of band 3 in the human kidney. We report here that the basolateral membrane of intercalated cells of the connecting tubules and collecting ducts contains an analogue of band 3 that appears to be highly homologous to the erythrocyte anion exchanger. This band 3-like protein is probably important for reabsorption of bicarbonate in the collecting duct system and thus for acidification of the forming urine. The band 3-like protein of the intercalated cells contain immunoreactive sites of both the cytoplasmic domain and the three major fragments of the membrane-spanning domain of erythrocyte band 3. Although no immunological differences were detected between the membrane-spanning domains of band 3 in erythrocytes and intercalated cells, there are at least three sites along the cytoplasmic domain of kidney band 3 that differ from erythrocyte band 3 in either amino acid composition or posttranslational modifications. The main kidney analogue of band 3 that contains epitopes of the cytoplasmic domain as well as the 17- and 35-kDa membrane-spanning domain of erythroid band 3 is a polypeptide with an apparent molecular mass of 100-110 kDa. Further immunoreactive polypeptides at approximately 180, approximately 140, approximately 38, approximately 25-30 kDa that were detected at lower stringency and higher sensitivity of the immunoblotting procedure may be members of a multigene family that encodes a series of related proteins.
The authors report a prospective 2-year outcome study of 40 inpatients with severe personality disorders who were treated on a specialized long-term unit for patients with "borderline conditions." Treatment goals included improving interpersonal relationships and facilitating a lasting discharge from the hospital. Data were collected at admission, discharge, and 1 and 2 years after discharge. The data reflect change from admission to follow-up in impulsivity, psychotherapy, and social adjustment. Mediating effects of length of stay on outcome are discussed.
Poor inter-rater reliability of the Strauss and Carpenter Outcome Criteria in hospital outcome study was attributed to lack of operational definition. A revision aimed at remedying this problem was used to rate a portion of the original sample of subjects. The revised form proved superior in interrater reliability for seven of the nine categories, suggesting that this more explicitly behavioral version may improve hospital outcome research.
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Renal carnitine metabolism was studied in isolated kidney cortex tubules from fed rats. The tubular distribution of free carnitine (C), acid-soluble short chain acylcarnitine (AcC), and total acid-soluble carnitine was measured. The content of the last-mentioned in rat cortical tubule suspensions was 2.85 +/- 0.15 nmol/mg protein, 46% representing AcC. In the absence of metabolic substrates the AcC/C ratio declined from 0.84 to 0.48 during incubation. The administration of 2mM acetoacetate or 2mM 3-hydroxybutyrate caused an increase in AcC by 45% and 51%, respectively. The rise in AcC was paralleled by a decrease in C, resulting in an increase of the tubular AcC/C ratio to 1.69 and 1.85, respectively. In the presence of 1 mM exogenous L-carnitine 35 +/- 6 nmol AcC/(mg protein X h) was formed. The addition of acetoacetate and 3-hydroxybutyrate led to a 3.5 to 3.8-fold rise in AcC formation. Other substrates which are likewise metabolized by proximal tubules were less effective. More than 90% of the formed AcC was recovered in the extracellular fluid. The results suggest that proximal renal tubule cells are the intrarenal site of carnitine acylation and may be involved in the regulation of blood and/or urinary carnitine acylation state.
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Between January 1982 and December 1983 14,666 high-risk individuals in the Canton of Zurich, which has one million inhabitants, received 36,234 hepatitis B vaccine injections. The annual number of acute hepatitis B cases dropped from an estimated 220 to 280 in 1981 to 177 in 1982 and 133 in 1983. This drop of 40-50% resulted mainly from reduced numbers of cases among health care workers, drug addicts and homosexuals. Vaccination was a factor responsible for the reduced incidence of hepatitis B among health care workers and drug addicts, high-risk categories substantial proportions of which had been vaccinated. There was no evidence of a secondary protective effect of vaccination extending to other high-risk groups.
Intravenous application of dehydroepiandrosterone sulphate (DHEA-S) was performed in 6 women with normal progress of pregnancy, 3 pregnant women with multiple pregnancy and 4 pregnants with intrauterine death of the foetus (32nd to 38th week). The oestetrol concentrations in blood serum were estimated during 5 h after the injection. In most cases an increase could be observed, but this was inhomogenous. The oestetrol concentration even rises in cases of intrauterine death of the foetus. In 7 cases of uncomplicated pregnancies the DHEA-S loading test was done within 2 to 6 h before delivery. The oestetrol concentration in the cord serum of the newborns was not higher than in controls without DHEA-S application, whereas oestradiol in maternal serum showed the expected rise. We conclude that the determination of oestetrol after DHEA-S loading can not be used for the judgement of the foetal situation.
Two Drosophila mutants are described in which the connections between the input to and the output from the mushroom bodies is largely interrupted. In all forms of the flies (larva, imago, male, female) showing the structural defect, olfactory conditioning is impaired. Learning is completely abolished when electroshock is used as reinforcement and partially suppressed in reward learning with sucrose. No influence of the mushroom body defect on the perception of the conditioning stimuli or on spontaneous olfactory behavior is observed. The defect seems not to impair learning of color discrimination tasks or operant learning involving visual cues.
In 16 patients with unstable angina pectoris 2 mg of nifedipine were infused intravenously for 1 hour. From coronary angiograms and cineventriculograms before and after nifedipine infusion vessel and stenosis diameters and global and regional left ventricular function were determined. Pressures in the left ventricle (Millar catheter tip manometer), aorta and pulmonary artery were measured continuously. Intravenous nifedipine infusion decreased left ventricular systolic pressure from 131.9 +/- 15.3 to 119.1 +/- 18.6 mm Hg (p less than 0.001) and mean aortic pressure from 94.4 +/- 13.6 to 85.8 +/- 15.0 mm Hg (p less than 0.01) and increased heart rate from 70.6 +/- 10.6 to 77.5 +/- 10.4, with no change in pressure rate product. Left ventricular volumes declined significantly (EDVI from 94.4 +/- 16.7 to 79.4 +/- 17.1 ml/m2 p less than 0.001, ESVI from 34.2 +/- 9.3 to 27.2 +/- 10.4 ml/m2 p less than 0.001). Ejection fraction increased slightly from 63.2 +/- 7.8 to 66.2 +/- 9.4% (p less than 0.05). Regional wall motion did not change, either in ischemic or in normally perfused areas. A change in coronary vessel or stenosis diameter was not observed. There was a remarkable 46% decrease in left ventricular enddiastolic pressure (from 11.1 +/- 5.1 to 6.0 +/- 2.3 mmHg, p less than 0.001) which developed slowly and not parallel in time to the afterload reduction. The cause appears to be the normalization of an increased left ventricular compliance documented by a significant decrease of the late diastolic dp/dV from 0.35 +/- 0.22 to 0.07 +/- 0.02 mm Hg (p less than 0.001) after nifedipine infusion. This implicates a direct myocardial effect of calcium antagonists on the ischemic myocardium.