PubMed Health⌕ Search

Biomedical subjects

B Wenzel

Publications and source records attributed to B Wenzel.

At least 19 recordsLinked to original sources
PubMed1995

Molecular cloning, sequencing and sequence analysis of the fox-2 gene of Neurospora crassa encoding the multifunctional beta-oxidation protein.

We present the molecular cloning and sequencing of genomic and cDNA clones of the fox-2 gene of Neurospora crassa, encoding the multifunctional beta-oxidation protein (MFP). The coding region of the fox-2 gene is interrupted by three introns, one of which appears to be inefficiently spliced out. The encoded protein comprises 894 amino acid residues and exhibits 45% and 47% sequence identity with the MFPs of Candida tropicalis and Saccharomyces cerevisiae, respectively. Sequence analysis identifies three regions of the fungal MFPs that are highly conserved. These regions are separated by two segments that resemble linkers between domains of other MFPs, suggesting a three-domain structure. The first and second conserved regions of each MFP are homologous to each other and to members of the short-chain alcohol dehydrogenase family. We discuss these homologies in view of recent findings that fungal MFPs contain enoyl-CoA hydratase 2 and D-3-hydroxyacyl-CoA dehydrogenase activities, converting trans-2-enoyl-CoA via D-3-hydroxyacyl-CoA to 3-ketoacyl-CoA. In contrast to its counterparts in yeasts, the Neurospora MFP does not have a C-terminal sequence resembling the SKL motif involved in protein targeting to microbodies.

3-Hydroxyacyl CoA Dehydrogenases↗
PubMed1994

T lymphocytes, CD68-positive cells and vascularisation in thyroid carcinomas.

Immunohistochemical detection and quantification of CD3- and CD45RO-positive lymphocytes and CD68-positive cells in 75 thyroid carcinomas of follicular cell origin revealed rising levels for these parameters associated with dedifferentiation. A parallel trend towards reduction of vascularisation, determined as CD31-positive blood vessels, with decreasing differentiation became evident, statistically only significant when well-differentiated follicular and anaplastic carcinomas were compared. Positive correlations could be demonstrated between the density of CD68-, CD3-, and CD45RO-positive cells as well as between the density of CD68-, and CD3-, and CD45RO-positive cells and vascularisation. These correlations were expected, as the interaction of CD68-positive cells and T lymphocytes results in the production of angiogenesis factors, ultimately leading to better vascularisation of the tumour. Nevertheless, the tumour cells themselves are variously capable of producing angiogenic substances. The obvious lack of positive correlation between the density of tumour-infiltrating cells determined in this study and vascularisation, despite reduced vascularisation in less differentiated tumours that contained increasing numbers of tumour-infiltrating cells, seems to be due to functional heterogeneity of morphologically similar tumours.

Antibodies, Monoclonal↗
PubMed1993

Analysis of cytokine profiles in synovial T cell clones from chlamydial reactive arthritis patients: predominance of the Th1 subset.

Subpopulations of human T cells (Th0, Th1 and Th2) can be distinguished by their cytokine-secretion pattern. Evidence is increasing from other studies that the outcome of a human disease may depend on the subpopulation of T cells that predominates at the site of inflammation. Reactive arthritis serves as a useful model of chronic inflammatory diseases, because the triggering antigen can be identified. Using this triggering antigen we raised 33 T cell clones reactive with Chlamydia trachomatis and 25 T cell clones that were not reactive, all from the synovial fluid of two patients suffering from Chlamydia-induced arthritis. Their cytokine secretion patterns for interferon-gamma (IFN-gamma), IL-2 and IL-4 were analysed, as also were mRNAs for IFN-gamma and IL-10 by in situ hybridization. Out of the 33 antigen-reactive clones 23 showed a Th1 pattern with IFN-gamma but not IL-4 secretion, while the remaining 10 exhibited a Th0 pattern. The clones that did not react with Chlamydia expressed all patterns of cytokine secretion, including a Th2 pattern, thus providing a control population that excludes bias in the sampling procedure. CD4 and CD8 clones displayed a similar cytokine-secretion pattern. In addition this study demonstrates for the first time the expression of IL-10 mRNA in T cell clones derived from synovial fluid, and this was not confined to the Th2 subset. The Th1 response that Chlamydia provoke can be regarded as appropriate for such an obligate intracellular pathogen.

Adult↗
PubMed1992

In situ hybridization of the mRNA for interferon-gamma, interferon-alpha E, interferon-beta, interleukin-1 beta and interleukin-6 and characterization of infiltrating cells in thyroid tissues.

Cytokine mRNA production in the thyroid tissues of patients with various thyroid diseases was analysed by in situ hybridization. In addition, infiltrating leukocytes were characterized by immunohistologic studies using the alkaline phosphatase anti-alkaline phosphatase (APAAP) staining technique. The following clinical material was investigated: two cases of Graves' disease, one with high and the other with a low amount of infiltrating leukocytes as well as two cases of non-toxic goitre also showing considerable quantities of infiltrating cells. The hybridization was performed on tissue sections with antisense probes for interferon-gamma (IFN-gamma), IFN-alpha E, IFN-beta, interleukin-6 (IL-6) and IL-1 beta. A small number of individual cells were found to express high levels of mRNA for IFN-gamma, IL-1 beta and measurable amounts of IL-6 throughout the tissue sections. However, IFN-alpha E or IFN-beta were not detected. Cytokine expressing cells were noted in the tissue of one patient with Graves' disease and in two cases with non-toxic goitre. In these samples a high amount of infiltrating leukocytes (CD45+) was detected, especially CD3+, CD8+, CD4+ and CD45RA+ T cells, in addition to B cells and macrophages. In one case an unusually large amount of T cell receptor gamma/delta+ (TcR gamma/delta+) cells was found. However, one sample of thyroid tissue derived from a patient with Graves' disease was poorly infiltrated and showed few cells expressing cytokines. In conclusion, using thyroid tissue as an example, our data suggest that the application of in situ hybridization with antisense RNA permits the study of cytokine production in tissues of both autoimmune and non-autoimmune origin.

Adult↗
PubMed1992

Peroxisomal multifunctional beta-oxidation protein of Saccharomyces cerevisiae. Molecular analysis of the fox2 gene and gene product.

The gene encoding the multifunctional protein (MFP) of peroxisomal beta-oxidation in Saccharomyces cerevisiae was isolated from a genomic library via functional complementation of a fox2 mutant strain. The open reading frame consists of 2700 base pairs encoding a protein of 900 amino acids. The predicted molecular weight (98,759) is in close agreement with that of the isolated polypeptide (96,000). Analysis of the deduced amino acid sequence revealed similarity to the MFPs of two other fungi but not to that of rat peroxisomes or the multifunctional subunit of the Escherichia coli beta-oxidation complex. The FOX2 gene was overexpressed from a multicopy vector (YEp352) in S. cerevisiae and the gene product purified to apparent homogeneity. A truncated version of MFP lacking 271 carboxyl-terminal amino acids was also overexpressed and purified. Experiments to study the enzymatic properties of the wild-type MFP demonstrated an absence of activities originally assigned to an MFP of S. cerevisiae (crotonase, L-3-hydroxyacyl-CoA dehydrogenase, and 3-hydroxyacyl-CoA epimerase), whereas two other activities were found: 2-enoyl-CoA hydratase 2 (converting trans-2-enoyl-CoA to D-3-hydroxyacyl-CoA) and D-3-hydroxyacyl CoA dehydrogenase (converting D-3-hydroxyacyl-CoA to 3-ketoacyl-CoA). The truncated form contained only the D-3-hydroxyacyl-CoA dehydrogenase activity. These results clearly demonstrate that the beta-oxidation of fatty acids in S. cerevisiae follows a previously unknown stereochemical course, namely it occurs via a D-3-hydroxyacyl-CoA intermediate.

3-Hydroxyacyl CoA Dehydrogenases↗
PubMed1990

Regional cerebral blood flow during focal seizures of temporal and frontocentral onset.

Ictal single photon emission computed tomography recordings were performed in 9 patients in the course of 11 seizures. Injections of radionuclide were made an average of 72 seconds after the onset of the seizure as indicated by electroencephalography. All patients also underwent interictal recordings. In 6 patients, the localization of the electroencephalographic focus and the morphological lesions corresponded with the ictal hyperperfusion. This could be seen in single photon emission computed tomography. Seizures triggered by hyperventilation, and seizures of patients with anatomical brain lesions (e.g., cysts, surgical defects, and recent injections of technetium-hexamethylene-propylene-amine-oxime) showed an absent or noncorresponding localization of the ictal recording. The ictal and interictal recording seems suitable as a confirmatory noninvasive method for the localization of the epileptogenic focus, particularly in the preoperative evaluation of epilepsy.

Adolescent↗
PubMed1990

[Direct capping of the artificial exposed pulp in teeth with deep caries].

We carried out clinical and histological investigations on teeth with superficial and deep caries in which we made an artificial exposure of the pulp to check the reactivity of the endodont. After one year we observed using clinical and x-ray methods successful treatment in 93.4% of the teeth. Histologically the number of successful treatment was 100.0% in teeth with superficial caries and 80.0% in teeth with deep caries.

Adolescent↗
PubMed1981

[Clinical importance of the estimation of thyrotropin displacing antibodies (author's transl)].

In 69 hyperthyroid patients with diffuse uptake in the scintigram, thyrotropin displacing antibodies (TDA) were measured before, during and after thyrostatic treatment. In a further 42 patients antibody activity was investigated before and 6-12 weeks after radio-iodine treatment, and in 29 patients it was measured before and after subtotal thyroidectomy. Persistence of demonstrable TDA during and after the end of drug treatment was in all cases indicative of recurrence of hyperthyroidism. On the other hand, disappearance of TDA activity was not a guarantee for prolonged remission as five patients had a recurrence despite loss of TDA activity. In a further nine patients hyperthyroidism reappeared with recurrence of TDA after varyingly long periods of remission. Thyrostatic treatment should be performed until disappearance of antibodies. Prolonged demonstration of TDA should lead to surgical intervention. Besides the usefulness in establishing the diagnosis of immunogenic hyperthyroidism (Graves' disease) TDA estimation may be of some prognostic value in the use of thyrostatics. In contrast, after radio-iodine treatment or operation the functioning capacity of the remaining thyroid tissue seems to be more relevant for the success of treatment than the possibly longer acting antibodies.

Antibodies↗
PubMed1981

Mitogenic response of peripheral blood lymphocytes from patients with Graves' disease incubated with solubilized thyroid cell membranes containing TSH receptor and with thyroglobulin.

Transformation of peripheral blood lymphocytes (PBL) in response to solubilized TSH receptor and to human thyroglobulin (hTG) was carried out in patients with Graves' disease (GD). Mean stimulation index (SI) in response to solubilized TSH receptor was significantly increased only in hyperthyroid GD patients (SI = 3.0 +/- 1.8 SD, n = 13, p less than 0.025) when compared to normal subjects (SI = 1.5 +/- 0.8 SD,n = 14). All other subgroups of GD patients (i.e., euthyroid GD patients after treatment as well as those with/without ophthalmopathy or TSH-displacing antibody [TDA]) showed a tendency to elevated mean SI, which, however, was never significantly increased. In contrast, patients who were suspected of having a "disseminated autonomy" showed a tendency to decreased mean SI compared to GD patients. The mitogenic response of PBLs induced by solubilized TSH receptor could be suppressed by incubation of antigen and PBLs with bTSH. Control experiments with purified protein derivate of tuberculin(PPD) as stimulating antigen revealed, however, that bTSH itself suppresses the mitogenic response of PBLs and that the decrease of SI in this experiment is not due to blockage of the antigenic determinants of the TSH receptor protein. Human thyroglobulin (hTG) produced no significant increase in the SI of PBLs. Only 9 out of 47 GD patients showed an SI higher than the mean of normals + 2 SD. All those patients, however, who showed an elevated SI ( greater than 2.0) also revealed an increased SI with solubilized TSH receptor.

Cell Membrane↗
PubMed1978

[Tooth mobility in several age groups with reference to various periodontal diagnostic aspects].

The present study deals with a study of the tooth mobility, the pocket depth and the bone destruction in 616 periodontally healthy subjects. It was found that the mobility of the upper lateral incisor is inferior to that of the central one. Furthermore, relations of age to tooth mobility and bone destruction were established, whereas no relationship between age and pocket depth was evident.

Adult↗
PubMed1977

Differentiation between various effects of cytotoxic fractions of lymphocyte culture medium.

This paper describes the partial characterization of supernatants derived from mitogen stimulated lymphocytes by ammonium sulfate precipitation, ultrafiltration on Hollow-Fiber beakers and gelchromatography. Fractions from these purification procedures were tested on FL-target cells and the following target cell alterations were measured: RNA- and protein synthesis, 3H-TdR incorporation, cell number and lysis of target cells. Target cell alterations of control fractions from supernatants of non-stimulated lymphocytes, from culture medium and from FCS were compared to the effects of fractions from activated lymphocytes. 3H-TdR incorporation was not only inhibited by the fractions of activated lymphocyte cultures but also by fractions of various controls. Inhibition of 3H-TdR incorporation disappeared when control fractions were serially diluted. Only fractions of supernatant from activated lymphocytes could lyse target cells. It were the same fractions which still inhibited 3H-TdR incorporation of target cells after serial dilution and which showed stimulating effects on RNA synthesis. MW of fractions which were differentiated from control fractions with respect to target cell lysis were: 90,000, 45,000 and lower than 20,000 d.

Cell Line↗
PubMed1976

[Studies on the mechanism of activation of lymphocyte membrane ATP-ases by concanavalin A (author's transl)].

The ouabain-sensitive and ouabain-intensitive ATP-ases of intact lymphocytes, and of the lymphocyte microsomal fraction and a purified plasma membrane fraction, are all activated by concanavalin A. The Na+, K+, and Mg+-dependence of the plasma membrane ATP-ases were defined at different substrate concentrations. Enzyme activation was rather greater at lower K+ concentrations. From these studies it appears improbable, but not impossible, that concanavalin A exerts an allosteric effect on the ATP-ases.

Adenosine Triphosphatases↗
PubMed1976

[Concanavalin A induced changes of lymphocyte p-nitrophenylphosphatase (author's transl)].

The effect of K+, Na+, Mg2+ and ATP on the p-nitrophenylphosphatase activity was investigated. As an enzyme preparation a microsomal fraction of sheep lymphocytes was used. Low concentrations of Mg2+, K+ and Na+ increased, whereas high concentrations decreased the enzyme activity. There was an inhibition of activity by ATP without Na+ in the incubation medium and an increase of enzyme activity at low K:Na-ratio. By concanavalin A in a concentration of 15 mug/ml the p-nitrophenylphosphatase activity was increased in intact cells and the microsomal fraction for 30-40%. The activation was not Na+, K+, Mg2+, p-nitrophenylphosphate or ATP dependent.

4-Nitrophenylphosphatase↗