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Biomedical subjects

L Kraus

Publications and source records attributed to L Kraus.

At least 37 records · Page 2Linked to original sources
PubMed1987

In vivo nitrogen dioxide exposure depresses spleen cell in vitro mitogenic responses: effects of sulfur compounds.

The in vivo mitogenic responses to lipopolysaccharide or concanavalin A by spleen cells of mice exposed to 20 ppm nitrogen dioxide (NO2) for 96 hr, were evaluated. [3H]Thymidine incorporation after addition of either mitogen, was significantly lower in spleen cells from acutely NO2-exposed mice (NO2 SC) than from control mice, although cell viability was not affected. T- and B-cell mitogenic responses were inhibited to the same extent by NO2 exposure. NO2 SC responses were protected by the thiol compounds 2-mercaptoethanol, L-cysteine, and selenomethionine. No restoration of mitogenic response was observed after treatment with reduced glutathione. Mechanisms accounting for this in vivo NO2 immune toxicity, are discussed in terms of oxidative injury.

Animals↗
PubMed1987

Total parathyroidectomy with autotransplantation in haemodialysed patients with secondary hyperparathyroidism--should it be abandoned?

The development of secondary hyperparathyroidism is almost universal in patients with end-stage renal disease. Medical management frequently fails and in such circumstances parathyroidectomy becomes a necessity. Total parathyroidectomy with autotransplantation of parathyroid tissue into the patient's forearm has been advocated as the surgical procedure of choice. In a previous publication we reported our experience with this technique in six haemodialysed patients. We now extend our follow-up to 19 patients over an observation period ranging from 6 to 66 months. Five of these patients required graft removal because of recurrent secondary hyperparathyroidism. Despite total graft removal, two patients had clinical and laboratory evidence of persistent hyperparathyroidism. Histology of the removed graft tissue demonstrated severe hyperplasia as well as invasion of adjacent muscle, adipose tissue, and vascular channels by parathyroid cells. This raises the possibility of local and distant metastatic spread of parathyroid tissue resulting in hyperparathyroidism. We suggest that parathyroid autotransplantation is potentially hazardous and should in fact be abandoned.

Female↗
PubMed1986

Glutathione status during the mitogenic response of rat splenocytes. Effects of oxygen concentration: FO2 21% versus FO2 7%.

Glutathione is known to be an important parameter for ConA proliferative response of murine splenocytes. We studied the glutathione status of ConA-stimulated rat splenocytes during the early and late phase of the mitogenic response under low (FO2 7%) and standard (FO2 21%) oxygen concentrations. We determined the intracellular total, oxidized and reduced glutathione levels after 6, 12, 24 and 48 h of culture with or without ConA and/or 2-ME, under FO2 7% and 21%. Our results showed that: The 2 GSSG/GSH + 2 GSSG ratio, which indicated the redox state of the cells, remained normal during the early period of culture (0-24 h), irrespective of culture conditions. After 48 h of culture, this ratio increased dramatically under FO2 21% and less under FO2 7%. The maintenance of the redox state seems to be an oxygen concentration-dependent phenomenon. ConA stimulation involved a glutathione consumption during the early stages of culture; under these conditions 2-ME increased the glutathione synthesis, which was higher under FO2 7% than under FO2 21%. On the other hand, the presence of 2-ME involved an increase of tritiated thymidine uptake in stimulated splenocytes, which was significantly higher under FO2 21% than under FO2 7%. Low oxygen tension (FO2 7%) can induce a higher increase of glutathione synthesis, whereas the respective ConA proliferative response is lower than that observed under standard O2 conditions.

Animals↗
PubMed1986

Resistant hypertension associated with a renin-producing ovarian Sertoli cell tumor.

A 17-year-old girl with refractory, but nonmalignant, hypertension and hypokalemia is presented. A state of primary hyperreninism and secondary hyperaldosteronism was found to exist, together with a renin-producing Sertoli cell ovarian tumor. Upon removal of the tumor, this patient attained both a normotensive and a normokalemic state. A brief review is given of renal and nonrenal renin-producing tumors.

Adolescent↗
PubMed1985

Lymphocyte glutathione status in relation to their Con A proliferative response.

We studied the intracellular total, oxidized and reduced glutathione levels in thymus and spleen rat lymphocytes cultured with or without Con A and 2-mercaptoethanol (2-ME). After 48 h culture, the total glutathione level decreased and the oxidized glutathione level increased in the two types of unstimulated and stimulated cells. In the presence of 2-ME, the tritiated thymidine incorporation increased in splenocytes but not in thymocytes; on the other hand, the two types of stimulated cells increased their total and oxidized glutathione content. The enhancement of the GSSG/GSH + GSSG ratio, irrespective of culture conditions, indicates a severely disturbed redox state of the cells. 2-ME acts on the glutathione synthesis of stimulated lymphocytes but is unable to maintain a normal redox state of these cells.

Animals↗
PubMed1985

High concentrations of oxygen modulate in vitro Con A responses of rat lymphoid cells. Effect of 2-mercaptoethanol.

The effects of different normobaric oxygen concentrations (40, 60 and 95%) on the survival and the proliferative response to Con A of rat lymphoid cells were studied. Spleen, thymus and peripheral blood mononuclear cells were tested. We found that oxygen concentrations modulated the proliferative response independently of cell survival. The addition of 2-mercaptoethanol (2-ME) partially prevented the toxic effects of hyperoxia but the population of thymocytes which responded to Con A stimulation appeared to be less sensitive to the protective action of 2-ME. The relationship between oxygen concentrations and the lymphoid proliferative response could be used as a model of oxidant immunodepression for evaluating pharmacological effects of antioxidant compounds.

Animals↗
PubMed1985

Depression of Con A proliferative response of immune cells by in vitro hyperoxic exposure--protective effects of thiol compounds.

Time dependent response for hyperoxic exposure was determined in vitro on ConA proliferative response of rat splenocytes, peripheral blood mononuclear cells and thymocytes. The proliferative responses were evaluated after different lengths of hyperoxic exposure (12-72 h, FiO2 = 0.95). After 24 h oxygen exposure, the spleen cell viability assessed by dye exclusion was normal but DNA synthesis was markedly suppressed in the above three types of cells. Total or partial protection of the mitogenic response to ConA was obtained by 2-mercaptoethanol, reduced glutathione or L-cysteine addition in culture medium; only selenomethionine had no protective effect. Thymic cells showed a different response-curve: after 6 h exposure to normobaric oxygen DNA synthesis was decreased and was not restored by any of the thiol compounds tested. In this respect, these cells demonstrated different susceptibility to an oxidant injury, i.e. exposure to high oxygen concentration. From a pharmacological point of view O2 exposure and altered immune response could be proposed as a useful model for screening the antioxidant drug activity.

Animals↗
PubMed1984

HLA antigens in Guillain-Barré syndrome.

We compared Guillain-Barré syndrome (GBS) cases reported from cities in the United States in 1976-1977 with spouse or associate controls to detect possible HLA associations. HLA-A11 was somewhat less common among 92 cases than among 100 controls (p = 0.04). The 38 patients and 42 controls vaccinated against A/NJ/76 differed slightly in overall distribution of B locus antigens (p = 0.06), but the individual HLA-B antigen associations were more easily explained by chance. The 54 unvaccinated cases showed no apparent relation to HLA type. These findings should encourage further immunogenetic study of etiologically related GBS cases.

Adolescent↗
PubMed1983

Characterization of immunological depression in mice exposed to normobaric oxygen.

Immunological cell functions were evaluated during 24, 48 and 96 h O2 exposure in C57Bl/6 mice. A normobaric O2 exposure resulted in depression of delayed type hypersensitivity (DTH) to oxazolone and Staphylococcus aureus antigens. This effect was proportional to the duration of O2 exposure. The antibody response of splenic cells was more rapidly (24 h O2 exposure) and markedly depressed using a T-dependent antigen (sheep red blood cell, SRBC) than with a T-independent antigen (trinitrophenylated lipopolysaccharide, TNP-LPS). While mitogen-induced proliferative responses of spleen cells to Con A and PHA were inhibited after 72 h of O2 exposure, proliferative responses to LPS were inhibited after 96 h. A dissociated antigen and mitogen responses was observed after a short time of O2 exposure (48 h): the antigen specific responses were impaired with a more pronounced effect on T lymphocytes, whereas the DNA synthesis in response to mitogen remained normal.

Animals↗
PubMed1983

[Mitogenic responses of splenic lymphoid cells of rats exposed in vitro to normobaric oxygen].

Rat spleen cells were cultivated in 1 ATA pure oxygen. The mitogenic responses with Con A were evaluated at different time of exposure (12 to 72 hrs). There was a stimulation of the cells after 12 hrs of exposure, which diminished at 18 hrs, in spite of the fact that the viability of the cells remained unchanged till 24 hrs of exposure. The kinetics of the mitogenic response of the splenic lymphocytes exposed to oxygen is biphasic as has been observed after irradiation.

Animals↗
PubMed1983

Successful parathyroid gland autotransplantation after total parathyroidectomy in dialysis patients.

Secondary hyperparathyroidism is one of the major complications encountered in patients on maintenance dialysis. Medical management is frequently unsuccessful, and there is often a need to perform a parathyroidectomy. Recurrent clinical secondary hyperparathyroidism may occur as a sequela of subtotal parathyroidectomy and necessitate a reexploration of the neck. Total parathyroidectomy followed by autotransplantation of parathyroid tissue into the patient's forearm bypasses the need for a second operation, and it provides a simple ambulatory procedure, under local anesthesia, for the removal of hyperplastic parathyroid tissue. The results in six patients indicate that this new procedure should be considered the treatment of choice for this condition.

Adult↗
PubMed1981

The watery diarrhea syndrome with hypercalcemia--a symptomatic response to phosphate buffer.

Two patients with the watery diarrhea, hypokalemia, achlorhydria syndrome are described. Both had hypercalcemia, hypophosphatemia and suppressed parathyroid hormone activity. On repeated occasions the diarrhea was controlled by oral or intravenous phosphate buffer. An exhaustive search by sophisticated non-invasive methods and by celiac arteriography failed to demonstrate a pancreatic tumor. Yet, in both cases fairly large pancreatic non-beta-cell adenomas were found at laparotomy. The removal of these tumors was followed by complete recovery.

Adenoma↗
PubMed1980

[Malignant melanoma, leukoderma and vitiligo].

We report about two patients with malignant melanoma, who developed vitiligo at a site distant from the primary melanoma after surgery and during consecutive immunotherapy. In two patients a leucoderma was observed within the area, where metastatic lymphnodes had been excised, as also reported in the literature. These depigmentations may be due to an immunologic defense mechanism, but there is no evidence, if they represent a favourable sign in the course of malignant melanoma.

Adult↗
PubMed1980

Altered protein synthesis and creatine kinase in breast muscle cell cultures from dystrophic chick embryos.

The total protein synthesis (TPS), myosin synthesis (MS) and creatine kinase (CK) levels in muscle cell cultures obtained from 400 normal (strain 454) and 400 dystrophic chick embryos (strain 455) were investigated. The cultures were obtained from breast muscles of 12 day chick embryos by dissociation in 0.25% trypsin, preplating and plating of 5 x 10(5) floating cells on gelatin coated dishes in Minimal Essential Medium, 10% horse serum and 2% chick embryo extract. After 6 days, when electron-microscopic studies demonstrated good muscle differentiation, cell cultures were labeled with [3H]leucine. TPS and MS, respectively, showed 85% and 65% increases in breast muscle cell cultures from dystrophic chick embryos. The half-life times for total protein and myosin from dystrophics were 19 and 32 hr, respectively as compared with 36 and 48 hr from controls. Noncollagen protein content (NCP) showed 27% decrease in postfusion stage (12 days) of cell cultures from dystrophics. The CK level showed 30% lower values in the cells from dystrophics but 50% higher values in their culture medium. The addition of leupeptin plus pepstatin (50 microgram/ml) to these cultures resotred NCP content, total protein and myosin turnover to normal values and significantly increased TPS and MS. The addition of diphenylhydantoin (DPH) (20 microgram/ml) to cell cultures from dystrophics did not change the NCP content nor the turnover for total protein and myosin but significantly increased TPS, MS and CK while medium CK significantly decreased. The addition of leupeptin plus pepstatin or DPH to muscle cell cultures from normal chick embryos also significantly stimulated TPS and MS.

Animals↗