Stimulation of the N-methyl-D-aspartate receptor has a trophic effect on differentiating cerebellar granule cells

N-methyl-D-aspartate (NMDA) supplementation of cerebellar cultures enriched in granule neurones (about 90%) prevented the extensive cell loss which occurs when cultivation takes place, in serum containing media, in the presence of 'low' K+ (5-15 mM). Estimation of tetanus toxin receptors and N-CAM contents indicated that NMDA rescued primarily nerve cells. The influence of NMDA in promoting cell survival was blocked by the receptor antagonist, 2-amino-5-phosphonovalerate. The effect depended both on the concentration of NMDA and on the degree of depolarization of cells, the affinity in the presence of 15 mM K+ being similar to that of NMDA receptor binding. The results attest a new role for excitatory amino acid transmitters by showing that they can exert a stage-dependent trophic action on developing nerve cells.     

Acute effect of endogenous inhibitors and exogenous cytostatics on the ultrastructure of bone marrow cells. I. Single dose of 1,2 : 5,6-dianhydrogalactitol (DAD).

The ultrastructural effects of the endogenous inhibitor, granuloid crude extract (GCE), known to control the proliferation of myeloid cells, and of the current hexitol derivative, 1,2 : 5,6-dianhydrogalactitol (DAD) were compared on the rat bone marrow. A single intraperitoneally injected LD50 dose of DAD induces the following changes in the fine structure: The mitochondria become swollen, the matrix less electron-dense, the cristae fragmentate, the ribosomes aggregate, anomalies appear in the perinuclear the cell membranes, and myelin figures and intranuclear bodies develop. Autophagy, degeneration and the phagocytotic activity of the reticulum cells is appreciable in 4 hours after treatment and increase by the 24th hour. The toxic effect of DAD is cell aspecific but in the ultrastructure its myelotropic effect manifests earlier than in erythropoiesis. In contrast, the arrest caused by a single dose of the endogenous granuloid inhibitor [2] is cell-specific and non-toxic.     

The influence of some antidepressant drugs on the nuclear volume of rat cingular cortex cells in culture

The changes in the volume of cell nuclei of the rat cingular cortex were investigated in culture after incubation with some antidepressant drugs. Two-week incubation of the cingular cortex culture with both tricyclic (desipramine, imipramine, amitryptyline) and non-tricyclic (mianserin) antidepressants in concentration of 3 X 10(-6) M resulted in a decrease of the volume of the cell nuclei. Because the size of the nucleus is regarded as a criterion of the cell metabolic activity, our results may point to a diminished activity of metabolic processes of the cells.     

Nasal mucosal expression of nitric oxide synthases in patients with allergic rhinitis and its relation to asthma.

BACKGROUND: Nitric oxide (NO) has contradictory roles in the pathophysiology of allergic inflammation in both allergic rhinitis (AR) and asthma. Small amounts of NO produced by constitutive NO synthase (NOS) is anti-inflammatory, whereas large amounts produced by inducible NOS (iNOS) are proinflammatory. OBJECTIVE: To investigate the difference in constitutive endothelial NOS (eNOS) and iNOS expression in nonallergic and allergic mucosa and the possible relation of this to the coexistence of asthma in seasonal AR. METHODS: Seventeen patients (10 women and 7 men) with seasonal AR and 9 nonallergic patients (5 women and 4 men) with nasal septum deviation were enrolled. Inferior turbinate nasal biopsy specimens were obtained in all. Levels of eNOS and iNOS expressed as immunohistochemical scores (HSCOREs) were determined immunohistochemically from the specimens. RESULTS: The mean +/- SD HSCOREs for eNOS in patients with seasonal AR were not significantly different from those of the nonallergic controls (1.85 +/- 0.78 vs 1.63 +/- 0.54; P = .12). On the other hand, the mean +/- SD HSCOREs for iNOS were significantly higher in patients with seasonal AR (1.75 +/- 0.75 vs 0.71 +/- 0.6; P = .004). Furthermore, although eNOS expression was not different between seasonal AR patients with and without asthma, the mean +/- SD HSCOREs for iNOS were significantly higher in the patients with asthma (1.93 +/- 0.78 vs 1.65 +/- 0.55; P = .01). CONCLUSION: Increased expression of iNOS might have a role in the development of allergic inflammation in upper and lower airways and in comorbidity of AR and asthma.     

The detection and characterization of viral-related double-stranded RNAs in tobacco mosaic virus-infected plants

The 2 M LiCl-soluble RNA fraction extracted from tobacco mosaic virus (TMV)-infected tobacco plants contains, in addition to the viral replicative form of 4 x 10(6) MW, three smaller double-stranded (ds) RNA species with apparent molecular weights (estimated by polyacrylamide gel electrophoresis, using ds RNAs as markers) of 2.25, 1.1, and 0.23 x 10(6). The synthesis of all four ds RNAs is insensitive to actinomycin D. They are completely RNase insensitive at high salt concentrations and are found both in directly inoculated and in apical tissues. In tissues incubated in the presence of 3H-uridine and actinomycin D, the three small ds RNAs accounted for 6 to 11.5% of the total radioactivity incorporated into viral ds RNA. On a molar basis, however, in apical leaves the smallest ds RNA was synthesized to almost the same level as the replicative form. By molecular hybridization, the three small ds RNAs have been shown to be of viral origin, and each contains sequences represented in the 5' end of complementary (negative strand) TMV RNA. Based on molecular weight data, none of the ds RNAs can be considered to be a ds form of the subgenomic TMV coat protein mRNA (the LMC), suggesting that it is not replicated independently. None of the small ds RNAs was found to be an endogenous product of the bound TMV RNA replicase.     

Twenty-four hour leukocyte adherence inhibition test in thyroid cancer patients

The effect of TG cell depletion taking place during 24 hour incubation on the leukocyte adherence inhibition phenomenon was investigated in patients suffering from cancer of the thyroid and healthy volunteers. The depletion coincided with the increase of the adherence inhibition if PPD was used as antigen in both groups, but the reaction to the tumour associated antigen could not be brought into relation with the depletion of TG cells.     

Genetic and biochemical background of chronic granulomatous disease

Chronic granulomatous disease (CGD) is a rare inherited immunodeficiency syndrome caused by a profound defect in the oxygen metabolic burst machinery. Activity of NADPH oxidase is absent or profoundly diminished, as at least one of its components (gp91(phox), p22(phox), p47(phox) and p67(phox)) is lacking or non-functional. This review explains the molecular basis of NADPH oxidase dysfunction by the effects of mutations in genes coding for particular oxidase components. Among the four types of CGD, the most common is X-linked CGD (approximately 65%), with defects in the CYBB gene encoding gp91(phox). A wide spectrum of mutations has been described in the CYBB gene with no predominant genotype. The second most common subtype of CGD caused by NCF1 mutation accounts for 30% of CGD patients and is inherited in an autosomal recessive manner, with predominance of a homozygotous deltaGT deletion in the genotype. The other two CGD subtypes having an autosomal recessive pattern together account for no more than 10% of CGD cases. A strategy for the molecular diagnostics in CGD patients is proposed and principles of genetic counseling are discussed here.     

Knowledge and Attitudes of Health Care Professionals and Laypeople in Relation to Brain Death Diagnosis and Organ Donation in Hungary: A Questionnaire Study

ObjectivesThe aim of the present work was to assess the knowledge and attitudes of different health care workers and laypeople toward the donation and transplantation procedure.Subjects and methodsA survey consisting of questions regarding brain death diagnosis, legal organization or organ donation, and the transplantation procedure were sent to participants: 56 intensive care unit (ICU) doctors, 76 ICU nurses, 188 sixth-year medical students, and 320 general practitioners (GPs). Laypeople were also asked to complete the survey.ResultsThe majority of participants reported being aware of legal regulations for organ donation in Hungary (88.5%). Roughly 25% of GPs and 60% of laypeople were unaware of the opt-out system effective in the country. Less than one-third of ICU physicians (26.9%) and nurses (34.7%) were able to list the organs that may be transplanted from a deceased donor; GPs (22.4%) and medical students (20%) performed even worse on this item. The willingness of ICU specialists (57%) and ICU nurses (45%) to support donating their own organs was moderate.ConclusionsThe results of this survey indicate a need for graduate and postgraduate education and regular teaching programs regarding organ donation and transplantation. More active use of modern media is proposed to improve public awareness and acceptance of organ donation.