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Biomedical subjects

M Berger

Publications and source records attributed to M Berger.

At least 901 records · Page 50Linked to original sources
PubMed1980

Transcarboxylase. An electron microscopic study of the enzyme with antibodies to biotin.

Antibodies prepared against biotin linked to serum albumin have been purified by affinity chromatography using lipoyl-Sepharose (Harmon, F. (1980) Anal. Biochem. 103, 58-63). These antibodies have been used to study the structure of the biotin-containing enzyme, transcarboxylase, by examination of complexes with the enzyme using electron microscopy. The antibodies are observed complexed with the outer subunit of transcarboxylase, which contains the biotin, but they also combine with the central subunit which does not contain biotin. Addition of excess biotin does not prevent combination of the antibodies with the central subunit. Such nonspecific combination does not occur with the outer subunit which has been treated with avidin-Sepharose to remove the biotinyl subunit. Large insoluble intermolecular enzyme complexes are not observed, apparently because the divalent antibodies react with the multiple sites on a single transcarboxylase molecule or because the larger complexes are unstable. Combination of the antibodies with the enzyme weakens the intersubunit linkages, thus, when grids are prepared for electron microscopy, there frequently is much greater dissociation of the enzyme which is complexed than there is with the noncomplexed enzyme. The results have confirmed that the biotinyl subunits remain complexed with the outer subunits when transcarboxylase dissociates.

Antibodies↗
PubMed1980

[Blood-sugar self control. A means for the diabetic of controlling his metabolic management. Quality control of a battery-run pocket size reflectometer (glucose-meter)].

Home blood glucose monitoring by diabetic patients has recently been advocated as an effective means to improve metabolic control. The Glucocheck apparatus, a pocket-size battery-driven reflectance-meter (in Germany commercially available under the name Glucose-meter), has been evaluated for accuracy and practicability. In 450 blood glucose measurements, the variance between the values obtained using the Glucocheck apparatus and routine clinical laboratory procedures was +/- 11.7%. Especially in the low range of blood glucose concentrations, the Glucocheck method was very reliable. The quantitative precision of the Glucocheck method depends, however, quite considerably on the ability of the patient to use the apparatus correctly. In order to profit from Glucocheck in clinical practice, particular efforts to educate the patients in its use are necessary.

Adult↗
PubMed1980

Oxygen consumption in perfused skeletal muscle. Effect of perfusion with aged, fresh and aged-rejuvenated erythrocytes on oxygen consumption, tissue metabolites and inhibition of glucose utilization by acetoacetate.

1. O2 consumption, glucose metabolism and the energy status of skeletal muscle were compared in isolated rat hindquarters perfused with aged (21--35 days), fresh and aged-rejuvenated human erythrocytes. 2. The age of the erythrocytes did not affect O2 consumption, glucose utilization or lactate release either at rest or during exercise. The concentrations of ATP, phosphocreatine and lactate within the muscle were also unaffected by the use of aged erythrocytes. 3. Perfusion with acetoacetate did not inhibit glucose utilization; but, it caused a marked increase in the tissue concentration of citrate in the soleus, a slow-twitch red muscle, and a smaller increase in the gastrocnemius, which contains fast-twitch red and white fibres. Results were similar in hindquarters perfused with aged and aged-rejuvenated erythrocytes. 4. These findings suggest that perfusion with aged human erythrocytes does not cause major alterations in the metabolic performance of the isolated rat hindquarter.

Acetoacetates↗
PubMed1980

[Obesity: state of research and therapy].

The classification of obesity into a hypertrophic and a hyperplastic type is apparently becoming less accepted since preadipocytes are not covered by investigation of adipose tissue cellularity. Obesity-associated insulin resistance is probably due to a decrease in number of insulin receptors, induced by hyperinsulinemia. Metabolic factors may contribute to insulin resistance. Long-standing hypersecretion of insulin may exhaust the B-cell, resulting in glucose intolerance and diabetes. There is increasing interest in the (possibly) disturbed energy metabolism in obesity, though clearcut conclusions are not yet possible. For the management of obesity an integrated treatment schedule is recommended including a 1000 calorie mixed diet, intensive nutritional education, motivation, group and individual psychotherapy, physical exercise and physiotherapy. Drastic methods for the treatment of obesity are critically reviewed.

Diet, Reducing↗
PubMed1980

Chemotherapy of autochthonous leukemias induced by 7,12-dimethylbenz(a)anthracene in Long Evans rats.

A total of 111 autochthonous (primary) acute rat leukemias of the diffuse-hepatic type which had been induced by 7.12-dimethylbenz(a)anthracene were treated with mono- and combination chemotherapy. The survival time of treated rats increased significantly compared to untreated controls. A combination of vincristine (VCR), adriamycin (ADR), and cytosine arabinoside (Ara-C) was superior to a combination of VCR and ADR as well as to a monotherapy with Cyclophosphamide, BCNU, VCR, ADR, and Ara-C.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1980

Analgesic effect of fluproquazone in postoperative patients.

In 4 double-blind, randomized, stratified, parallel group studies, single oral doses of fluproquazone (75 to 200 mg), a new nonsteroidal anti-inflammatory analgesic, were compared with aspirin (1,000 mg) and placebo in a total of 672 hospitalized patients with moderate or severe pain following episiotomy or other surgical interventions. A dose-dependent effect of fluproquazone which was highly significantly superior to placebo and which resembled the effect of aspirin with respect to onset, degree, and duration was noted in all studies. Fluproquazone, 100 to 150 mg, was found to be approximately equiactive to 1,000 mg of aspirin and better tolerated.

Adult↗
PubMed1980

In vitro and in vivo studies on glucagonoma tissue.

A 66 year old patient with diabetes had a necrolytic migratory erythema, weight loss and anaemia. Plasma immunoreactive glucagon (IRG) of 2465 pmoles/l (normal 35 +/- 5 SEM pmoles/l) suggested the existence of a glucagonoma which was confirmed by arteriography and subsequently removed by surgery. Although plasma IRG returned to normal, glucose tolerance and insulin secretion remained pathological. Plasma amino acid levels had been reduced but were corrected by surgery. Pancreatic polypeptide, however, 298 pmoles/l before was still 206 pmoles/l after the operation (normal 12-48 pmoles per litre). Column chromatography of plasma and tumor extracts showed quantitatively important IRG fractions with molecular weights above 9000 daltons, possibly precursors of glucagon. Beside a 50-fold IRG excess, the tumour concentrations of insulin and somatostatin were 4 to 150 times increased. By contrast, pancreatic polypeptide was present in normal amounts. Electron microscopic examination showed atypical A-cell granula and unusual abundance of mitochondria.

Aged↗