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Biomedical subjects

M Kessel

Publications and source records attributed to M Kessel.

At least 127 records · Page 7Linked to original sources
PubMed1981

Cytoplasmic helical structure associated with Acholeplasma laidlawii.

A distinct spiral protein structure was found in three species of Acholeplasma, but was not found in the Mycoplasma species studied. The spirals, which are 14 nm in width and of variable length from 50 to 300 nm, are formed by a helical arrangement of 7-nm subunits. A rosette-like structure 45 nm in diameter also composed of 7-nm subunits was found in close association with the spirals and may be a taut in vivo form of the spiral. The electrophoretic profile in sodium dodecyl sulfate-polyacrylamide gels indicated that the spirals are composed of a predominant polypeptide with an apparent molecular weight of 100,000. No evidence can be found for inferring actin-like properties for this structure.

Acholeplasma↗
PubMed1981

Outpatient evaluation of dietary intake and nitrogen removal in continuous ambulatory peritoneal dialysis.

Five patients on continuous ambulatory peritoneal dialysis were studied to evaluate dietary intake, glucose absorption from the dialysate, and urinary and dialysate nitrogen removal. The study was done on an outpatient basis, while the patients ingested their usual diets and went about their usual activities. The results indicate that patients greatly overestimated their caloric and protein intake, which was 0.71 to 0.96 g/kg bodyweight per day. Dialysate glucose contributed considerably to total caloric intake, because approximately 75% of of the dialysate glucose was absorbed independent from total glucose administered, providing 20% to 29% of the total caloric intake. We concluded that protein requirement in clinically stable continuous ambulatory peritoneal dialysis patients still needs defining because the patients may be anabolic with lower protein intakes than previously recommended.

Aged↗
PubMed1981

Iron incorporation into ferritin and hemoglobin during differentiation of murine erythroleukemia cells.

Hemoglobin and ferritin iron content have been followed during differentiation in tissue cultures of murine erythroleukemia cells (MELC) using the techniques of Mössbauer spectroscopy and electron microscopy. In undifferentiated cells grown without DMSO, only iron stored in ferritin was detected. The amount of iron in a cell grown in the presence of iron citrate is approximately 1.2 X 10(-14) g, whereas in a cell grown in the presence of transferrin the amount is approximately 0.28 X 10(-14) g. These quantities do not depend on the iron concentration in the nutrition medium in a range from 0.3 to 2.0 microgram Fe/ml and are the same for growth times between 8 hr and 7 days. Cells grown with DMSO contain, in addition to ferritin, increasing concentrations of hemoglobin. Chase experiments prove that ferritin iron participates in hemoglobin synthesis. The amount of ferritin iron reaches saturation within less than 8 hr in MELC grown with or without DMSO. In differentiating cells grown with iron citrate there is a decrease with time in ferritin iron content concomitant with the increase in hemoglobin. Cells grown with transferrin incorporate additional amounts of iron, which are approximately equal to the amounts used for hemoglobin synthesis maintaining a constant ferritin iron level. In the electron microscope, iron is seen only as ferritin within lysosomes. The density of the ferritin in lysosomes correlates with the ferritin iron concentrations determined by Mössbauer spectroscopy.

Animals↗
PubMed1981

Nutritional behaviour of patients on continuous ambulatory peritoneal dialysis.

Seven patients on home continuous ambulatory peritoneal dialysis (CAPD) were investigated for their spontaneous nutritional behaviour. Energy intake with dialysate glucose gain amounted to 130kJ/kg BW/day. The distribution found was: 56% carbohydrates, 35% fat and 10.9% protein. The protein intake opposed by peritoneal loss of aminoacids (1.76g/day) and of proteins (9.4g/day) amounted to 0.78g/kg BW/day. Subtraction of the peritoneal loss yields only 0.58g/kg/day; however, estimation of total nitrogen balance was slightly positive and nutrition related serum proteins remained comparable to other dialysis patients.

Aged↗
PubMed1980

Archaebacterial elongation factor is ADP-ribosylated by diphtheria toxin.

Archaebacteria have been defined as a 'third primary kingdom' of cells in addition to the urkaryotes and the eubacteria. While the latter two correspond approximately to the conventional categories eukaryotes and prokaryotes respectively, the Archaebacteria have up to now comprised four groups of microorganisms: the methanogenic bacteria, the extremely halophilic bacteria and the two thermoacidophilic genera Sulfolobus and Thermoplasma. Based on ribosomal RNA sequence homologies and lipid composition, they apparently form a distinct group. Furthermore they possess or lack typical biochemical markers of both the eukaryotes and the prokaryotes, as well as having unique properties not found elsewhere. Altogether, this indicates that they are not closer to either one of the classical categories. One clear-cut difference between prokaryotes and eukaryotes is the diphtheria toxin reaction, which catalyses the covalent binding of adenosine diphosphate-ribose (ADPR) to the eukaryotic peptide elongation factor EF2 in contrast to the homologous prokaryotic factor EF-G. We report here that diphtheria toxin also catalyses the ADP-riboslation of archaebacterial elongation factors. In this respect, these factors have to be assigned to the EF2 type; we suppose that the ADP-ribosylatable structure arising so early in evolution is of fundamental importance for the elongation process.

Adenosine Diphosphate Ribose↗
PubMed1980

Averages of glutamine synthetase molecules as obtained with various skin and electron dose conditions.

Averaged projections of individual glutamine synthetase molecules have been obtained by using electron microscopy and image processing. The methodology of correlation averaging under low dose conditions is described in detail. Because of their low signal-to-noise ratio, images made under low dose conditions cannot be directly interpreted in terms of high resolution features. Computer averaging of these images reveals a division of the subunit projection into two domains whose sizes agree with results of Lei et al [2] limited proteolysis experiments.

Chemical Phenomena↗
PubMed1980

Efficacy of an unselected protein diet (25 g) with minor oral supply of essential amino acids and keto analogues compared with a selective protein diet (40 g) in chronic renal failure.

The efficacy of a mixed protein-poor diet (25 g) with an intake of only 12 tablets of essential amino acids or keto analogues (= 0.9 Rose units) was compared with that of a selective protein diet (40 g). Twenty-eight patients with chronic renal insufficiency (creatinine clearance 13.2 +/- 5.6 ml/min per 1.73 m2) were included in the prospective study with four periods of 3 months each. Each patient served as his own control. The mixed protein-poor diet showed a better patient compliance irrespective of the type of supplement. In addition, the essential amino acid supplementations showed no advantages over the standard diet. In patients with a creatinine clearance less than 10 ml/min, the keto analogue supplementation led to an improvement of the uremic intoxication and the nutritional state. An increase in renal function was not observed. The phosphate decrease occurred even when there were signs of portein malnutrition.

Adult↗
PubMed1980

Iron storage in Mycoplasma capricolum.

Considerable quantities or iron were incorporated into the Mycoplasma capricolum cell membrane. Mossbauer studies showed that the iron is in a form which becomes magnetically ordered at low temperatures. The iron-enriched cells contained membrane-bound electron-dense particles of about 6.0 nm in diameter.

Cell Membrane↗
PubMed1980

Ornidazole in the prevention of infections after abdominal hysterectomy.

Following informed consent, 226 consecutive patients scheduled to undergo abdominal hysterectomy entered a randomized double-blind clinical trial to determine the efficacy of ornidazole versus placebo in the prevention of postoperative infections. Postoperative abscesses occurred in 2 patients (1.8%) in the ornidazole group compared to 5 patients (4.4% in the placebo group. Febrile episodes occurred in 6 patients (5.3% receiving ornidazole and in 13 patients (11.4%) receiving placebo.

Abscess↗
PubMed1980

Clinical and metabolic aspects of continuous ambulatory peritoneal dialysis (CAPD).

Experience with CAPD in 14 patients, treated for periods of 2-10 months, is presented. Clinical and biochemical control of uremia appeared adequate in all patients except one. Control of extracellular volume and hypertension was easier with CAPD than with intermittent peritoneal dialysis (IPD). Nine episodes of peritonitis occurred in 5 patients (one peritonitis/8 patients months). Mean protein loss was 9.7 +/- 2.7 g per day. In 6 patients on IPD oral glucose tolerance test resulted in a paradoxical rise of HGH, whereas this was not observed after 4 months of CAPD.

Adult↗
PubMed1979

[Continous ambulatory peritoneal dialysis (CAPD)].

Eleven patients were treated with continuous ambulatory peritoneal dialysis (CAPD) for periods of 2-7 months (48 patient-months). Clinical and biochemical control of uremia was adequate in all patients. Control of hypertension and serum phosphate level was easier than with previous intermittent peritoneal dialysis (IPD). Mean protein loss during CAPD was 9.7 +/- 2.7 g/day. Seven episodes of peritonitis occurred in 3 patients (1 peritonitis/6.8 months). General use of CAPD cannot be recommended until the high incidence of peritonitis is reduced by urgently needed technical improvements. A potential complication of CAPD was that triglycerides were markedly elevated in 4 patients.

Adult↗
PubMed1979

[Effect of Co-trimoxazole on renal creatinine excretion in man (author's transl)].

Clinical observations have shown, that administration of Co-trimoxazole (Trimethoprim-Sulfamethoxazole) may result in an elevation of the serum-creatinine level. In 27 subjects the endogenous creatinine- and inulinclearance were measured before and during oral or parenteral application of Co-trimoxazole. The inulinclearance showed no significant differences (p greater than 0,05). But the endogenous creatinine clearance showed a reduction of 18% during the oral and of 13% during the parenteral treatment (p less than or equal to 0,05). These observations indicate a functional inhibition of the tubular creatinine secretion by Co-trimoxazole.

Adult↗
PubMed1979

Hemodynamic studies in long-term peritoneal dialysis patients.

A study was undertaken to evaluate the acute hemodynamic effects in ten patients from this clinic's long-term peritoneal dialysis program. With a Swan-Ganz catheter, the following parameters were measured in each patient during peritoneal dialysis: cardiac index, pulmonary artery pressure, right atrial pressure, inferior vena cava pressure, heart rate and arterial pressure. Mean predialysis cardiac index, stroke volume index and heart rate were normal. Predialysis pulmonary artery pressure and arterial pressure were slightly elevated. Mean weight loss during peritoneal dialysis was 1.6 kg. The most striking post-dialysis changes were a significant 20% decrease of the cardiac index and a 17% decrease of the pulmonary artery pressure. Heart rate and arterial pressure remained constant due to a 25% increase of total peripheral resistance. After filling the abdomen with one, two and three liters of dialysate, intra-abdominal pressure and inferior vena cava pressure increased up to 150 and 100%, respectively, whereas central hemodynamic parameters (pulmonary artery pressure, cardiac index, stroke volume index, heart rate and arterial pressure) were unchanged.

Adult↗
PubMed1979

Central and peripheral haemodynamics in longterm peritoneal dialysis patients.

A study was undertaken in 11 longterm peritoneal dialysis (PD) patients to evaluate the acute haemodynamic effects of PD. After filling the abdomen with 1, 2 and 3L of dialysate, intra-abdominal pressure and inferior vena cava pressure increased up to 140 and 98% respectively, whereas central haemodynamic parameters were unchanged. Venous capacity decreased by 18%. Mean weight loss during PD was 1.6kg. The most striking post-PD changes were a significant 19% decrease of cardiac index and 18% decrease of pulmonary artery pressure. Heart rate and arterial pressure remained constant due to a 24% increase in total peripheral resistance.

Adult↗
PubMed1979

Recirculation dialysis (RD) (20 to 40 liters of dialysate) with venous bicarbonate buffering - an alternative procedure to hemofiltration (HF).

We report about a dialysis procedure, the circulation stability of which is comparable to hemofiltration treatment. Hemodynamic parameters were measured invasively and different procedures were compared for each patient. In RD and HF significant reduction in cardiac output (HF: --20%, RD: --21.5%), stroke volume (HF: --20%, RD: --17%), pulmonary artery pressure (HF: --57%, RD: --45:6%) and plasma volume (HF: --12%, RD: --15%) were found. Blood pressure and heart rate (HF: --1%, RD: --3%) remained stable despite the high utrafiltration rate. Peripheral resistance rose significantly (HF: + 20%, RD: + 25.9%). Compared with HG, the most important advantage during RD is the improved tolerance to treatment without typical hemodialysis-induced symptoms. In comparison to that, we found under conventional dialysis an inadequate increase in peripheral resistance (HD: + 6.1%). A following strong compensatory hyperventilation with drop in PCO2 was paralleled with typical symptoms like nausea and headache. Because of resttriction of this compensatory mechanism, hypotension and arrhythmia will be induced of the following peripheral tissue perfusion and central acidosis.

Bicarbonates↗
PubMed1978

Hemodynamic studies, acid-base status and osmolality in different hemodialysis procedures.

Three patients on maintenance dialysis were each treated with three different procedures: A) twenty-liter recirculation dialysis with bicarbonate buffering, B) recirculation-adsorption dialysis and C) single-pass dialysis. Hemodynamic parameters were measured invasively and procedures A, B and C were compared for each patient. In this intraindividual comparative study, the authors attempted to establish a relationship between the varying hemodynamic parameters and the changes in osmolality and acid-base status. There were indications of some causal relationship to circulatory stability: in A and B, there were peripheral resistance increases of 24.5% and 38.4%, respectively, with stable circulation; in C, there was a 6.1% increase and unstable circulation. Additionally, the influence of acidosis is shown in B, with disproportionately strong reductions of cardiac output (21.9%) and pulmonary artery pressure (44.9%); In spite of a decrease of osmolality (A: 15.6 mOsm/L), stable circulation could be achieved if the peripheral resistance was substantially increased and acid-base status was equalized.

Acid-Base Equilibrium↗