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M Hohenegger

Publications and source records attributed to M Hohenegger.

At least 73 records · Page 4Linked to original sources
PubMed1984

On the statistical estimation of speech-organization distributions from aphasia data.

Statistical methods of estimating speech-organization distributions from aphasia data are presented. Under certain assumptions, estimators for the proportions of individuals with unilateral right-hemisphere speech, unilateral left-hemisphere speech and bilateral speech organization are derived, and the large-sample properties of these estimators are presented. It is shown that useful results can be obtained when the most questionable assumption is relaxed. The general methodology is presented in terms of a specific example--the estimation of speech organization distributions of right- and left-handed adults across the three speech types. Under the relaxed assumptions a test of the hypothesis that all left-handers are unilaterally organized is derived. Conservative bounds on the proportions of unilaterally organized (left- and right-hemisphere) and bilaterally organized left-handers are also derived. As an illustration, the results are applied to aphasia-incidence data from the literature. Several uncertainties and inadequacies of the available data are discussed. Although minor modifications of the present methods might be required for other examples, the main ideas would be the same.

Adult↗
PubMed1980

Energy metabolism in acute uremic rats.

In rats kept under starvation for 25 h after bilateral nephrectomy VO2 is reduced to about 50% of the normal value. The body temperature is conspicuously low (33--34 degrees C), the blood pH about 7.1. Raising the body temperature to normal values by keeping the rats in a thermostat does not influence the low metabolic rate. The prevention of acidosis by repeated application of bicarbonate in the postoperative period has no effect on VO2. Tube feeding with glucose + oil or glucose + oil + casein does not improve the metabolic rate. However, the total glycerol plasma levels, already high in the state of starvation, are still more elevated. It is considered that the primary effect of acute uremia is to suppress the metabolism, as a consequence of which the body temperature is lowered.

Animals↗
PubMed1980

Nitrogen metabolism and growth in experimental uremia.

Growth in length, weight gain and gain of body nitrogen were compared in rats with stable long-term uremia (U) resulting from subtotal two-stage nephrectomy with irradiation of residual parenchyma, in sham-operated pair-fed control rats (PFC) and in ad libitum fed control rats (LC). Growth in length and weight gain were considerably lower in U than in LC rats, reflecting mainly diminished intake of food in uremia. However, they were also significantly lower in U than in PFC despite identical intake of food, pointing to a specific adverse effect of uremia on growth. Whole body dry matter, whole body nitrogen and weight of a reference muscle (triceps surae) were significantly lower in U than in PFC animals, showing that dietary nitrogen and/or energy are less efficiently utilized for protein synthesis in U animals. Diminished net nitrogen retention was paralleled by increased urinary nitrogen loss (excretion of urea, alpha-amino nitrogen, protein, and creatinine). Within the precision of the method used, no significant difference of oxygen consumption between U and PFC animals could be demonstrated. The plasma amino acid pattern was deranged and the tyrosine/phenylalanine ratio was decreased despite no change in hepatic phenylalanine hydroxylase. The findings document increased nitrogen and/or energy cost of growth in rats with stable chronic uremia; this finding agrees with previous observations of disturbed protein metabolism and hypercatabolism in experimental uremia.

Amino Acids↗
PubMed1979

[On the effect of cadmium on tissue respiration and gluconeogenesis in rat kidney cortex (author's transl)].

Oxygen consumption (QO2), respiratory quotient (RQ) and gluconeogenesis of rat kidney cortex slices were determined (Warburg technique). QO2 was not influenced by 0.01 mM CdCl2 in the incubation medium (no exogenous substrate added), 0.1 mM, 1mM and 10 mM, respectively, reduced QO2 by 43%, 45% and 68%. In the presence of 8 mM glucose, 10 mM acetate or 5 mM butyrate, 1 mM Cd resulted in a decrease in QO2 by about 50% each. Addition of 20 g/l albumine to the medium abolished this effect of cadmium. RQ was not influenced by a mM Cd, both without and with 8 mM glucose in the medium. Glucose production from 7 mM pyruvate or 5 mM glutaminate in slices from fed and starving rats was reduced by 1 mM Cd to half the value found in controls.

Albumins↗
PubMed1979

Lipid metabolism in uremic and nonuremic acidosis.

In bilaterally nephrectomized rats and in normal rats treated with 0.1 N HCl elevated levels of plasma total glycerol and lowered FFA and free glycerol are observed after a period of 25 h of starvation. In both cases the removal of intravenous lipid loads is slowed down, plasma LA is decreased after starvation and after lipid loads. The bicarbonate treatment of nephrectomized rats tends to normalize the plasma lipid levels and LA as well as the removal of intravenous lipid loads. The etiological importance of acidosis in uremic hypertriglyceridemia and possible clinical significance is pointed out.

Acidosis↗
PubMed1979

Metabolic studies in rats under glucose and glycerol loading.

It has been found in rats that 40% glycerol, when added to standard diet, reduces the food intake and thus prevents weight gain. The subcutaneous application (40 mg/kg three times daily) has no effect. Under pair feeding conditions the oxygen consumption, the RQ value and body weight remain unaffected as compared with controls receiving glucose. It is concluded that reduction of body weight induced by glycerol feeding is due to reduced amount of food intake and not due to any alterations of energy metabolism.

Animals↗
PubMed1978

[Effect of sodium fluoride on the metabolism of the rat kidney cortex and medulla].

Tissue sections of cortex and outer and inner medulla of rat kidneys were examined in the Warburg apparatus with and without addition of NaF. It was shown that the O2 consumption was not significantly reduced in the presence of 0.05 mM F (=0.95 ppm F!) or smaller amounts. The respiratory quotient was not changed by NaF. Lactate formation in sections from the inner medulla was reduced to the same degree as O2 consumption. Maximal concentrations of plasma fluoride which are met in doses of fluoride used for the prophylaxis of caries, do not impair renal metabolism.

Animals↗
PubMed1977

[Patterns of renal and haemodynamic functions in cadaver kidney donors under dopamine (author's transl)].

Haemodynamics and renal function have been examined before and during i.v. infusion of dopamine (175 microgram/min) in 11 patients admitted as potential kidney donors to an intensive care unit. The findings of the control period revealed an extreme decrease of renal tubular function which points to a cessation of central regulation. The cardiovascular system showed a slight increase of blood pressure and heart rate during dopamine. Urine flow and renal blood flow increased significantly as well as the excretion of sodium while inulin-clearance showed only a minimal rise. The functional renal impairment under conditions of brain death as well as the influence of dopamine on circulation and renal function are discussed. The results indicate that dopamine may exert a favourable effect in preparation of kidney donors for the withdrawal of the organs.

Adolescent↗
PubMed1976

Lipid composition of the rat kidney.

The lipid fractions free fatty acids, triglycerides, cholesterol, cholesterol esters and phospholipids of rat kidney cortex, outer and inner medulla were analyzed by thin-layer chromatography. The concentrations of 23 individual fatty acids in the lipid fractions of each zone were determined by gas chromatography; 14 of them were evaluated by an analysis of variance. For most of the lipid fractions a corticomedullary concentration gradient was found, the highest concentrations occurring in the cortex. The lipid classes primarily determined the pattern of individual fatty acid concentrations. A significant concentration difference between the three zones only existed for 4 of 14 fatty acids. Long chain fatty acids were found in a higher concentration in the phospholipids of cortex and outer medulla (about 95%) in comparison to the inner medulla (65%).

Animals↗