Two CD14 promoter polymorphisms and atopic phenotypes in Czech patients with IgE-mediated allergy

BACKGROUND: Immunoglobulin E (IgE)-mediated allergy belongs to common chronic disorders resulting from an interaction between both genetic and environmental factors. The gene encoding CD14 is a positional candidate gene for allergic diseases as it is localized on chromosome 5q31.1, a region that is linked to asthma and bronchial hyperresponsiveness. Recently, several polymorphisms in the promoter region of this gene have been associated with atopic phenotypes in various populations. METHODS: We investigated relationship among atopic phenotypes and two polymorphisms [C(-159)T and G(-1359)T] in the promoter of the CD14 gene in the Czech population. Polymerase chain reaction with restriction fragment length polymorphism analyses was used to determine the CD14 genotypes in subjects with IgE-mediated allergic diseases (n = 562) and random controls (n = 320). RESULTS: The CD14 allele or genotype distributions were similar in patients and control group. However, the frequency of the C allele of the C(-159)T polymorphism was higher in patients with positive skin prick tests for moulds than in patients without reactivity to this antigen (P < 0.002, Pcorr<0.01). In addition, we found that patients with homozygous genotype (GG) of the G(-1359)T polymorphism had marginally lower percentage of positive skin prick tests compared with the other genotypes (P < 0.029, Pcorr > 0.05). CONCLUSIONS: Our study supports the idea that CD14 gene variants may act as disease modifiers of IgE-mediated allergic diseases.     

Pathogenesis of primary respiratory disease induced by isolates from a new genetic cluster of bovine viral diarrhea virus type I

The pathogenesis of infection induced by cytopathogenic isolates from the newly identified genetic cluster Id of bovine viral diarrhea virus (BVDV) type I was studied in two experimental infections of previously seronegative, immunocompetent calves. Experiment 1 focused on the evaluation of clinical patterns, viremia, and serological responses. All infected calves in this experiment developed respiratory symptoms and seroconverted to BVDV positivity. Contact calves also contracted a respiratory tract infection following exposure to infected animals. Viremia was demonstrated between postinfection days 2 and 17, and the virus was detected in organ specimens of all but one each of the infected and contact calves. In experiment 2, the distribution of BVDV in various tissues of calves euthanized at defined days postinfection was studied. In two of these calves recurrent shedding of BVDV in nasal secretions was shown. BVDV was detected in various tissues of all infected calves throughout the experiment and also following seroconversion and the clearance of BVDV from the circulatory system. Despite the widespread distribution of the virus in various organs, significant tissue damage was found mainly in respiratory tract and lymphoid tissues. These experiments revealed that viruses from cluster Id of BVDV are able to induce primary respiratory disease in previously seronegative, immunocompetent calves. Contact transmission and virus recurrence, contrary to observations from acute experimental infections with noncytopathogenic BVDV, are likely to reflect differences in biological features of these cytopathogenic isolates. Virus shedding and its presence in tissues following peripheral clearance and in the presence of antibodies may have implications in the diagnosis, pathogenesis, and epidemiology of BVDV-induced syndromes in cattle.     

Change in sympathetic activity,cardiovascular functions and plasma hormone concentrations due to cold water immersion in men

The purpose of this study was to determine whether or not repeated short-term cold water immersions can induce a change in the activity of the sympathetic nervous system and, consequently, in cardiovascular functions in healthy young athletes. Changes in some plasma hormone concentrations were also followed. A single cold water immersion (head-out, at 14°C, for 1 h) increased sympathetic nervous system activity, as evidenced by a four-fold increase (P < 0.05) in plasma noradrenaline concentration. Plasma adrenaline and dopamine concentrations were not increased significantly. Plasma renin-angiotensin activity was reduced by half (P < 0.05) during immersion but plasma aldosterone concentration was unchanged. Stimulation of the sympathetic nervous system during immersion did not induce significant changes in heart rate, but induced peripheral vasoconstriction (as judged from a decrease in skin temperature) and a small increase (by 10%) in systolic and diastolic blood pressures. No clear change in reactivity of the sympathetic nervous system was observed due to repeated cold water immersions (three times a week, for 6 weeks). Neither the plasma renin-angiotensin activity, aldosterone concentration nor cardiovascular parameters were significantly influenced by repeated cold water immersions. A lowered diastolic pressure and an increase in peripheral vasoconstriction were observed after cold acclimation, however. Evidently, the repeated cold stimuli were not sufficient to induce significant adaptational changes in sympathetic activity and hormone production.     

The measurement of transforming growth factor type beta (TGF beta) levels produced by peripheral blood mononuclear cells requires the efficient elimination of contaminating platelets.

In recent years there has been an increasing interest in measuring the levels of TGF beta produced by peripheral blood mononuclear cells (PBMC), since its abnormal regulation seems to be involved in several pathological states. Platelet-contamination, a common feature in PBMC populations isolated by the standard Ficoll-Paque method, would theoretically disturb the measurement of the levels of TGF beta produced by mononuclear cells, since platelets represent an important source of this cytokine. In this study, supernatants of PBMC cultures from healthy subjects, either platelet-contaminated or uncontaminated, were assayed for TGF beta activity in three different bioassays. We report that the presence of platelets led in most cases to an important overestimation of the TGF beta levels produced by MNC in the Swiss-3T3 bioassay and in a PBMC proliferation assay. In contrast, in the Mv1Lu bioassay these levels were significantly underestimated, an effect which we attribute to the presence of other platelet-derived growth factors. These results suggest that the elimination of platelets from PBMC cultures is essential if TGF beta production by mononuclear cells is to be studied.     

Characterization of T lymphocyte subsets in hairy cell leukaemia: influence of splenectomy and correlations with the clinical stage of the disease.

Peripheral blood mononuclear cell surface markers were studied in a series of 26 hairy cell leukaemia patients 19 of whom were splenectomized previously. Patients with non-symptomatic and stable disease were distinguished from those with symptomatic and/or progressive disease (also termed "active" clinical stages). In all HCL patients as a group, the absolute number of CD4+ MN cells did not differ statistically from that of the controls, while the number of CD8+ MN cells was significantly increased. The reduction of the CD4/CD8 ratio in the peripheral blood of HCL patients as compared to the controls was explained by the reduction of this ratio in patients with "active disease", while the CD4/CD8 ratio of patients with non-symptomatic and stable disease did not differ statistically from that of the controls. The CD4/CD8 ratio was found to be influenced mainly by the clinical stage of the disease, and not by the effect of splenectomy.     

Identification of histiocytic reticulum cells by the immunohistochemical demonstration of factor XIII (F-XIIIa) in human lymph nodes

Morphologically and enzyme histochemically distinguishable tissue macrophages and stromal cells of human reactive lymph nodes were characterized by the cytoplasmic presence of the subunit A of factor XIII and by the expression of surface antigenic determinants reacting with monoclonal antibodies directed against monocyte/macrophage populations (Mo 1, Leu M3) and HLA-DR antigens. The distribution of F-XIIIa positive cells was studied on formaldehyde-fixed paraffin-embedded sections with immunoperoxidase techniques. established on cryostat section with double immunofluorescence. Alpha-Naphthyl acetate esterase (ANAE) reaction was The immunophenotype was established on cryostat sections with double immunofluorescence. Alpha-Naphthyl acetate esterase (ANAE) reaction was carried out on these cryostat sections to identify tissue macrophages. The antibody against F-XIIIa detected histiocytes in both intra- and extra-sinusoidal locations which were ANAE+, Mo 1+, Leu M3+ and HLA-DR-. F-XIIIa was also present in fibroblast-like mesenchymal cells with the following phenotypic characteristics: ANAE-, Mo 1+, Leu M3+ and HLA-DR+. The anti F-XIIIa antibody did not stain lymphoid cells, granulocytes, epithelial cells, endothelial cells and mast cells. The immunohistochemical detection of F-XIIIa works on formaldehyde-fixed paraffin-embedded sections. The most promising application seems to be the identification of histiocytes in lymphoid and histiocytic proliferations.     

Corticoliberin activity of rat neurohypophysis is distinct from vasopressin

Electrical stimulation of the neural lobe of the pituitary resulted in an increase of corticosterone secretion in both normal and Brattleboro rats. Bioassaying the corticoliberin (CRF) activity of stalk-median eminence and neural lobe extracts obtained from normal and Brattleboro rats revealed that the endogenous vasopressin was not a prerequisite of ACTH-releasing potency. Arginine-8-vasopressin failed to potentiate the CRF activity of the different extracts. These data suggest that a nonvasopressin substance(s) with CRF activity can be released from the neurohypophysis of the rat, and it may contribute to activating the pituitary-adrenal axis under certain experimental conditions.     

Molecular pathology of well-differentiated thyroid carcinomas

The newly discovered molecular features of well-differentiated thyroid carcinomas derived from follicular cells are reviewed, within the frame of the 2004 WHO classification of thyroid tumours, under the following headings: “Follicular carcinoma”, “Papillary carcinoma”, “Follicular variant of papillary carcinoma” and “Hürthle cell tumours”. A particular emphasis is put on the meaning of PAX8–PPARγ rearrangements, RAS and BRAF mutations, and deletions and mutations of mitochondrial genes and of nuclear genes encoding for mitochondrial enzymes, for thyroid tumorigenesis.