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Biomedical subjects

M Roth

Publications and source records attributed to M Roth.

At least 361 records · Page 20Linked to original sources
PubMed1982

Loss of neurons of origin of the adrenergic projection to cerebral cortex (nucleus locus ceruleus) in senile dementia.

To examine the possibility that senile dementia may be associated with a loss of noradrenergic neurons that innervate the cerebral cortex, we used a Quantimet 720 image analyzer to estimate the number of neurons in the nucleus locus ceruleus in elderly patients with the clinical diagnosis of senile dementia. In all but one case, the diagnosis was established histopathologically as senile dementia of the Alzheimer type (SDAT). In a subgroup characterized by a high dementia score and relatively young age at death, there was a loss of about 80% of locus ceruleus neurons. This loss of neurons indicates a deficit of noradrenergic innervation to cerebral cortex in a group of patients which may represent a variant of SDAT.

Adrenergic Fibers↗
PubMed1982

Some properties of porcine carboxypeptidase N.

Some properties of carboxypeptidase N purified from pig serum have been investigated. The amino acid composition resembles that of human carboxypeptidase N, but differs markedly from that of porcine carboxypeptidase B. The enzyme contains a mass fraction of 0.1 carbohydrates. Both ester and peptide substrates are hydrolyzed at the same site. Peptide substrates are hydrolyzed if lysine or arginine is the C-terminal amino acid, and provided that the penultimate amino acid is not proline. Argininic acid and epsilon-aminocaproic acid are good inhibitors of the enzyme.

Amino Acids↗
PubMed1982

Biochemical characteristics of non-streptomycin-producing mutants of Streptomyces griseus. II. Lipids and fatty acid composition of vegetative mycelia.

Five non-streptomycin-producing non-aerial-mycelium-forming mutants (Str-Amy-) of Streptomyces griseus obtained either by spontaneous degeneration or during continuous cultivation of the high-producing aerial-mycelium-forming parent strain HP (Str+Amy+) were checked with regard to the composition of mycelial lipid material. All the Str-Amy- derivatives differed from their ancestor strain HP by an increased ration of 12-methyltetradecanoic acid (aC15:0) to isopalmitic acid (iC16:0) during growth on a chemically defined medium lacking branched-chain amino acids. This finding attests alterations in the availability of precursors for the biosynthesis of methyl-branched fatty acids. The qualitative composition of phospholipids and other polar lipids in one mutant group was found to be similar to the progenitor strain but, additionally, both a yellow pigment and a neutral lipid component were produced in excess. A second type of mutant differed by its incapability to form ornithinolipids even under phosphate limitation. Changes of phospholipid composition were demonstrated in the course of fermentation. Formation of ornithinolipid was suppressed by an excess of inorganic phosphate in the medium, while the portions of phosphatidylethanolamine and cardiolipin increased strongly. Furthermore, the formation of ornithinolipids was influenced by nitrogen sources. these results suggest that the composition of membrane of S. griseus varies in dependence upon the composition of the medium and the age of the mycelium.

Cell Membrane↗
PubMed1981

Biochemical characteristics of non-streptomycin-producing mutants of Streptomyces griseus. I. Role of NAD (P)-glycohydrolase in cell differentiation.

Five non-streptomycin-producing mutants of an industrial strain of Streptomyces griseus lacking aerial mycelium formation were compared with their genetic ancestor and another producing mutant with regard to the NAD(P)-glycohydrolase activity during cultivation on different media. By contrast to producing strains, all the Str- Amy- mutants displayed much lower mycelial and extracellular levels of enzyme, thus confirming earlier contentions concerning its involvement in control by phospho-adenosinediphospho-ribose of the intermediary metabolism at the sites of the citric acid cycle and the catabolism of the carbohydrates during distinct stages of cell differentiation. On the other hand, in the producing strain the biosynthesis of NAD(P)-glycohydrolase was demonstrated to depend on the regime of fermentation. Repeated stages of submerged cultivation in stirred fermentors resulted in suppression of enzyme formation without concomitant change of the mycelial capacity to produce streptomycin. This suggests that there is no direct involvement of NAD(P)-glycohydrolase in the control of antibiotic biosynthesis.

Kinetics↗
PubMed1981

Maintenance and genetic stability of vector plasmids pBR322 and pBR325 in Escherichia coli K12 strains grown in a chemostat.

The maintenance and genetic stability of the vector plasmids pBR322 and pBR325 in two genetically different Escherichia coli hosts were studied during chemostat cultivation with glucose and ammonium chloride limitation and at two different dilution rates. The plasmid pBR322 was stably maintained under all growth conditions tested. However pBR325 segregated from both hosts preferentially during glucose limitation and at low dilution rate. In addition to this general segregation process a separate loss of tetracycline resistance was observed. The remaining plasmid conferred resistance to ampicillin and chloramphenicol only, without any remarkable alteration of its molecular weight. Cultivation conditions in the chemostat were found that allowed the stable genetic inheritance of both plasmids in the hosts studied.

Ammonium Chloride↗
PubMed1981

Idiopathic scoliosis from the point of view of the neuroradiologist.

There is a simple morphological interrelation between the growing spinal cord-nerve root complex and the vertebral column, not unlike that between the growing brain and skull. The shape of the enveloping vertebral skeleton mirrors the anatomical features of the enclosed neural contents. During the cranio-caudally directed growth, spurts of elongation of the vertebral column may be too rapid for the slower growth rate of the spinal cord and nerve roots. The resulting disproportion of growth between spine and nervous system is compensated for by adaptive scoliotic curvature of the otherwise normally growing spine. The proposed pathogenetic concept readily explains the main clinical features of the deformity and is supported by a spring model experiment.

Humans↗
PubMed1981

Problems in the classification of affective disorders.

Some of the concepts which have figured prominently in recent studies of the classification of affective disorders are examined. The include the "primary-secondary", the "bipolar--unipolar" and the depression/anxiety dichotomy. The problems posed by these three principles are closely entwined with one another. Inconsistencies in diagnosis will arise from the application of these principles until a broad consensus has been achieved regarding the nature of the relationship between "vital" or "endogenous" depression and other disorders of affect. Allocation into one of these two broad categories has to be made prior to all other diagnostic decisions within the field on affective disorder. Hence differences in the classification and nomenclature of emotional illness between the United States and European countries will cause groups of patients comprising "unipolar", "primary" and "secondary" disorders to differ in composition until divergent viewpoints have been resolved. There is a hierarchial order implicit in the Kraepelinian system of classification which should be made more explicit; it would foster standardisation and consistency in diagnostic practice. But the order of precedence should be regarded as a set of hypotheses rather than fixed rules. Some recent observations regarding schizo-affective and schizomanic disorders have refused one of these hypotheses and so refined knowledge.

Anxiety Disorders↗
PubMed1981

Assessment of myocardial sympathetic activity in coronary heart disease.

We measured adrenaline, noradrenaline and dopamine beta-hydroxylase in arterial and in coronary sinus blood in 14 patients with coronary artery disease, at rest and under pacing-induced ischemia. Pacing increased the concentrations of adrenaline and noradrenaline in both arterial and coronary sinus blood. The origin of the adrenaline increase appears to be extramyocardial. The arteriovenous differences indicated that the heart extracts adrenaline and releases noradrenaline. These differences were not significantly changed by pacing, nor by the administration of propranolol. No marked changes in the concentrations of dopamine beta-hydroxylase were observed, except under pacing after propranolol, in which case a release from the heart occurred.

Adult↗
PubMed1981

Fluid-phase SC5b-8 complex of human complement: generation and isolation from serum.

A rapid, simple method for isolating SC5b-9 generated in human serum, and SC5b-8 generated in C9-depleted serum is described. The procedure leads to approximately 30% recovery of either complex and consists of polyethyleneglycol precipitation followed by 1 DEAE ion exchange chromatography and a sucrose density gradient ultracentrifugation. The SC5b-8 complex is a water-soluble macromolecular of alpha-electrophoretic mobility. Apart from the absence of C9, it exhibits an identical SDS-gel electrophoresis polypeptide pattern as SC5b-9. A sedimentation coefficient of 19 to 20S and an effective molecular radius of approximately 10 nm were determined by sucrose density gradient centrifugation and gel filtration, respectively. From these values, a m.w. of 800 to 850,000 is tentatively assigned to the SC5b-8 complex. The S-protein was not dissociable from either SC5b-8 or SC5b-9 through treatment with desoxycholate and no alterations in the hydrodynamic properties of either complex were discernible after action of this detergent.

Alpha-Globulins↗
PubMed1981

A novel alkaline proteinase associated with the actomyosin complex from pig uterine myometrium.

A novel proteolytic activity has been demonstrated an partially characterized in the actomyosin complex isolated from smooth uterine muscle. This proteolytic activity showed an alkaline pH optimum, was inhibited by SH-group-blocking reagents but not by metal-chelating agents and copurified with the actomyosin complex. An important characteristic of this alkaline proteolytic activity was that it seems to hydrolyze the actomyosin by limited proteolysis with a concomitant loss of the myosin adenosinetriphosphatase activity.

Actomyosin↗
PubMed1981

Controlled intracellular proteolysis during postpartal involution of the uterus: characterization and regulation of an alkaline proteinase.

The postpartal involution of the uterus is predominantly due to cellular hypotrophy. This implies an intracellular proteolytic system which must be carefully controlled pre and post partum. We have characterized and partially purified a proteinase with an alkaline pH-optimum of activity and a proteinase inhibitor protein which inhibits this proteinase very strongly. The alkaline proteinase copurifies with the actomyosin complex of the uterine myometrium and degrades the actomyosin complex with a concomitant loss of its myosin-ATPase activity. The alkaline proteinase is a very labile enzyme, markedly sensitive to SH-group modifying agents and has very high molecular weight at the present state of purification. This proteolytic enzyme could specifically be separated from the main components of the actomyosin complex by extraction with low ionic strength phosphate buffers. The proteinase inhibitor protein may control the activity of this alkaline proteinase during pregnancy and involution. The inhibitor protein raises 15-fold during pregnancy, possibly blocks important steps of intracellular proteolysis and permits organ growth. The dramatic fall of the inhibitor protein activity after parturition, which precedes the loss of weight, could release the proteolytic system, including the alkaline proteinase, and permits controlled intracellular degradation.

Actomyosin↗