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Biomedical subjects

J Allen

Publications and source records attributed to J Allen.

At least 415 records · Page 23Linked to original sources
PubMed1979

Cardenolide analogs. An explanation for the usual properties of AY 22241.

AY 22241 (AY) was compared with digitoxigenin with respect to effects on myocardial contractility and inhibition of Na+, K+-ATPase. Ay was less potent than digitoxigenin but otherwise showed the same type of rapid onset and rapid reversal of activity usually associated with genins. Since AY is a glycoside, its behaviour was regarded as anomalous since glycosides usually show both slow onset and slow reversal of activity. Attempts were made to account for the genin-like properties of AY in terms of the model for the digitalis receptor proposed by Thomas et al. (1974a,b). It is suggested that the low potency and genin-like properties of AY may be due to the fact that the steroid is attached to the lactone through the carbon atom that is alpha to the carbonyl group. This feature could result in non-alignment of the sugar residue with the sugar binding site and might also reduce the effectiveness of the interaction of the steroid moiety with its binding site. A notable feature of AY toxicity was its extremely rapid progression to irreversible fibrillation.

Animals↗
PubMed1979

Inhibitors of fibrinolysis in diabetic children, mothers, and their newborn.

Late diabetic complications are often related to vascular changes and formation of thrombi in the altered vasculature. Contributing factors to thrombosis susceptibility of diabetic patients include changes in clotting factors, platelets, and inhibition of fibrinolysis. We have measured various fibrinolytic inhibitors in the blood of diabetic children, diabetic pregnant women and their offspring, and healthy controls. Inhibitors studied included 1) fast (immediate) antiplasmin, 2) slow (progressive) antiplasmin, 3) alpha-2-macroglobulin, and 4) alpha-1-antitrypsin. It appears from our study that high fast-antiplasmin levels, and low or missing slow-antiplasmin levels are characteristic of diabetic patients and of newborn of diabetic mothers. The reason for high fast-antiplasmin levels is not clear: Levels are not connected with the age of the patient or duration of diabetes, and are not elevated in response to a fibrinolytic process (fibrin decomposition products could not be shown to be present in the serum of diabetic children). Alpha-2-macroglobulin was significantly higher and alpha-1-antitrypsin significantly lower in diabetic women than in controls. In the other groups of patients studied differences in these inhibitors from the appropriate control groups were not statistically significant.

Adolescent↗
PubMed1979

The effects of bromosulphophthalein, indocyanine green and bilirubin on the biliary excretion of methylmercury.

The effects of three ligands for ligandin on the biliary excretion of methylmercury were investigated in male rats injected intravenously with 1.0 mg/kg Hg as Me203 HgCl. Bromosulphophthalein and indocyanine green inhibited the biliary excretion of methylmercury, while bilirubin had no such effect. None of the compounds tested which inhibited the biliary excretion of methylmercury decreased bile flow or changed the hepatic concentration of mercury of non-protein thiols. The possibility of the involvement of ligandin in the biliary excretion of methylmercury is discussed.

Animals↗
PubMed1979

A call for leadership.

Explore the source record for details and available documents.

American Nurses' Association↗
PubMed1979

Tissue distribution of inhaled mercury vapor in acatalasemic mice.

Substantial differences were observed in the pattern of tissue deposition in normal versus acatalasemic mice after inhalation of radioactive mercury vapor. Liver deposition was approximately double and lung deposition approximately one-half the corresponding deposition in normal animals. These results lend further support to the idea that the hydrogen-peroxide catalase peroxidative pathway plays a role in the metabolism of inhaled mercury vapor.

Acatalasia↗
PubMed1978

Some properties of sialyltransferase in plasma and lymphocytes of patients with chronic lymphocytic leukemia.

Some properties of sialyltransferase activity in plasma and lymphocytes from patients with chronic lymphocytic leukemia were compared. Three distinct enzyme fractions were identified in plasma: (1) cation independent, irreversibly bound to agarose; (2) cation dependent, weakly bound to agarose; (3) strongly bound to agarose, lost upon dialysis. Lowering of the peripheral lymphocyte count by leukapheresis markedly decreased the level of serum sialyltransferase, suggesting the circulating lymphocyte is a source of the serum enzyme. The enzyme solubilized by detergent from lymphocytes showed a substantially lower Km for CMP-sialic acid than did the serum enzyme, was less sensitive to several inhibitors, was not irreversible bound to Agarose, and had a substantial cation requirement. The enzyme solubilized from the lymphocyte therefore generally resembles fraction 2 of serum.

Cations, Divalent↗
PubMed1977

Phenylketonuria masked by low protein feeds.

Two patients with phenylketonuria (PKU) requiring treatment were fed on low protein milks. Both had blood phenylalanine levels below 1200 micronmol/l (20mg/100 ml) until given a phenylalanine challenge. Phenylalanine content of mature breast milk may provide intakes similar to those used in treating PKU. Diagnosis of PKU is unlikely to be missed if screening is carried out on the sixth or seventh day of life because of higher phenylalanine in breast milk during the first week. Interpretation of screening tests requires knowledge of the infants' feeds and a blood phenylalanine above 360 micronmol/l (6 mg/100 ml) in the absence of tyrosinaemia requires careful investigation.

Animals↗
PubMed1977

Infusion thrombophlebitis in a surgical department.

In hospitals where 5% glucose is the solution most often infused, the incidence of thrombophlebitis has been found to be 27-43%. In an attempt to reduce this incidence, the following principles for the administration of intravenous solutions were established in a surgical department: (1) No cannula to be placed in the same vein for continuous infusion for a period of more than 24 hours, (2) All sugar solutions to be neutralized with a phosphate buffer. (3) The thinnest possible cannulas are to be used. (4) Vein irritant solutions to be given as quickly as permissible. (5) Veins with the largest diameter to be used first. These principles were adhered to for a period of 4 months. The daily infusion period was 11-14 hours. Of 196 patients who received infusions for a total of 529 days, infusion thrombophlebitis developed in 6.1% (3-10%). 113 of these patients received (among other solutions) 1000-2000 ml 10% invertose per day. This solution was given for an average of 4 days. 9.7% (5-17%) of the patients in this group developed infusion thrombophlebitis. No patient had more than one episode of infusion thrombophlebitis.

Buffers↗
PubMed1977

The measurement of obsessionality: first validation studies of the Lynfield obsessional/compulsive questionnaires.

The difficulties encountered in attempts at the rating and quantification of obsessional behaviour are outlined and some of the reasons for such difficulties are mentioned. The development of the Lynfield Obsessional-Compulsive Questionnaire from the Leyton Obsessional Inventory is discussed together with the advantages and disadvantages attendant upon its administration. The author concludes that the Lynfield Obsessional-Compulsive Questionnaire promises well as a measure for assessing change and that, following further validity and reliability tests, it may be used in multicentre trials of treatment procedures.

Evaluation Studies as Topic↗