Acute ulcerative colitis during successful interferon/ribavirin treatment for chronic hepatitis.
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Biomedical subjects
Publications and source records attributed to R Sprenger.
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Glutathione S-transferase theta enzyme activity involved in the metabolism of toxic compounds is absent in approximately 20% of Caucasians due to a homozygous deletion of GSTT1 (*0/0). Because the exact manner of the GSTT1 deletion was unknown, current genotyping of GSTT1 was limited to detect the presence versus complete absence of the gene by a GSTT1-specific polymerase chain reaction (PCR). Thus, heterozygous (*A/0) and homozygous (*A/A) samples could not be discriminated. We have characterized the boundaries of the deletion of the human glutathione S-transferase theta (GSTT1) gene: PCR mapping and sequencing revealed a 54251 bp fragment including GSTT1 to be deleted from chromosome 22, most likely by a homologous recombination event between two highly homologous sequence stretches that flank GSTT1. Based on the knowledge of the GSTT1*0 region, a PCR assay was devised for unambiguous discrimination of homozygously deleted (*0/0), heterozygously (*A/0) and homozygously GSTT1 carrying (*A/A) individuals. Genotyping of 180 samples of a Caucasian population revealed that the deletion consists of one defined allele, whose distribution in the population fits the Hardy-Weinberg equilibrium with observed 20% *0/0, 46% *A/0 and 34% *A/A individuals. The number of GSTT1*A alleles detected by this procedure correlated highly significant with the enzyme activity in erythrocytes. Genotype-phenotype comparisons demonstrated a codominant type of inheritance by a gene-dose effect: samples with two active alleles expressed a statistically significant higher enzymatic activity compared to those with one null allele (P < 0.0001, ANOVA).
By immunization with nuclear lysates of L428 cells, we raised a monoclonal mouse antibody, Ki-S2 (IgG1). In Western blots, this antibody recognizes a nuclear antigen with an apparent molecular mass of 100 kD, termed p100. Protein sequencing of p100 showed that this is a hitherto unknown protein. Immunohistochemical examination of cryostat and paraffin sections of nearly all human tissue types and neoplasms showed that p100 was exclusively expressed in the nuclei of a fraction of proliferating cells. Cell sorting and fluorescence-activated cell sorting analysis of stimulated peripheral blood mononuclear cells showed that p100 was exclusively expressed in proliferating cells from the transition G1/S until the end of cytokinesis. During mitosis, this protein is strictly associated with the spindle pole and with the mitotic spindle, whereas during S and G2, p100 is diffusely distributed throughout the cell nucleus. Immediately after completion of cytokinesis, p100 was rapidly degraded. In L428 cells, p100 is phosphorylated at least during mitosis. It has a turnover time of about 1 hour. Studies on routinely processed paraffin sections of specimens of malignant lymphoma, benign and malignant nevocellular tumors, and breast cancer showed that in all cases less than 40% of the Ki-67-positive growth fraction expressed p100. Thus, p100 might prove to be a more reliable measure of cellular proliferation and one that is more closely correlated to cancer prognosis, beyond its general biologic relevance as a cell cycle protein.
A PCR method is described for determining the expression of multiple heterogeneous mRNAs from single cells. The total mRNA pool of a single selected cell is subjected to reverse transcription and subsequent tailing with poly(dA). This cDNA is preamplified by a sequence non-specific PCR protocol using oligo(dT)-containing primers. The single cell cDNA library obtained permits the analysis of virtually unlimited numbers of mRNA species per cell using sequence-specific PCR. This procedure of multiple mRNA analysis enables phenotyping of any cell for its mRNA composition and could be used to study the cytokine mRNA expression of individual human T cells ex vivo. The method should greatly facilitate the analysis of combinatorial expression of known genes in any cell.
OBJECTIVE: The paper reports on the recruitment of a multicenter study on ambulant prophylactic treatment of schizophrenic disorders. METHODS: For a study of the relapse-preventative effect of different dose patterns of Flupentixol, a screening phase was carried out among of 1129 schizophrenic patients. The aim of the screening phase was to establish the criteria for exclusion or inclusion in the treatment phase of the study. RESULTS: Only 62 patients could be included. The reason for 54 patients not being included was a lack of compliance from either the patient or the clinician. The meaning of patient- and therapist-compliance in carrying out a multicenter study is also discussed.
Cytokine gene expression was investigated in the germinal centre constituents of follicular dendritic cells and germinal centre T cells and compared to the mRNA expression of nongerminal centre tonsillar cells. Cells were isolated from human tonsils by preenrichment with MACS and subsequent FACS sorting. Cytokine gene expression was investigated by intronspanning RT-PCR for IL-1 alpha, IL-1 beta, IL-2, IL-4, IL-5, IL-6, IL-10, IFN-alpha, IFN-beta, IFN-gamma, and TNF-alpha. Frequency of cytokine-producing cells and the cytokine production pattern of single cells were determined by single cell PCR. Furthermore, cytokine protein expression was investigated by immunohistology. Using these methods, we found a strong production of IL-1 beta mRNA and protein in a small percentage of FDC. Germinal centre T cells showed production of IL-2, IL-4, IL-10, IFN-gamma, and TNF-alpha mRNA. The mRNAs of these cytokines could also be detected at the single cell level; as they were produced in a high percentage of germinal centre T cells, whereas immunohistological staining was negative, we conclude that a high percentage of germinal centre T lymphocytes produce IL-2, IL-4, IL-10, IFN-gamma, and TNF-alpha in low concentrations in contrast to T cells outside the germinal centre, in which strong cytokine production in few cells was shown earlier.
Lymphoid organs have been proposed to function as the major reservoir for the human immunodeficiency virus type 1 (HIV-1). Within lymphatic tissues germinal centers represent foci of rapidly proliferating B cells governed by the interaction between B and T cells and follicular dendritic cells (FDC). Accumulating evidence suggests an important role of FDC in the pathophysiology of the acquired immunodeficiency syndrome. Direct proof for the infectibility of FDC with HIV-1 has been lacking until recently when we were able to demonstrate a CD4-independent infection of FDC in vitro. Here we report that in vitro HIV-1-infected human FDC do not only contain proviral DNA, but also produce the virus, and transmit the infection to T cells. Furthermore, electron microscopical studies on ex vivo isolated FDC from simian immunodeficiency virus (SIV)-infected rhesus monkeys revealed typical virus budding. In addition, FDC from SIV-infected rhesus monkeys transmitted the infection to T cells in vitro. Due to this central role within the immune response FDC may serve as preferential targets for HIV both by trapping of virions on their surfaces and by productive infection. During disease FDC become productively infected and may, thus, be regarded as crucial elements in viral dissemination.
Monoclonal antibodies were raised against prostacyclin synthases purified from bovine and porcine aortae, respectively. Two monoclonal antibodies, RS1 and RS2, were purified and characterized. As shown by enzyme activity precipitation and Western blot analysis, in solubilized bovine and porcine aortae microsomes the monoclonal antibodies reacted only with prostacyclin synthase. The monoclonal antibody RS1 cross-reacts with partially purified prostacyclin synthase from human umbilical veins in an ELISA-based assay. None of the antibodies inhibited the enzyme activity. By combination of the monoclonal antibody RS2 with a polyclonal antibody we established an enzyme-linked immunosorbent assay (ELISA) for quantitation of bovine prostacyclin synthase. ELISA data were confirmed by Western blot analysis. Among different bovine tissues, aortae with 1665 +/- 200 ng/mg microsomal protein showed the highest content of PGIS. Significant lower concentrations were observed in tongue, lung, kidney and thymus ranging from 49 +/- 13.4 to 2.7 +/- 0.9 ng/mg protein. The monoclonal antibody RS1 binds to endothelial cells and vascular smooth muscle cells in human liver tissue.
The structural variability of the external glycoproteins of primate immunodeficiency viruses, has, so far, been investigated exclusively by sequence comparison of the respective proviral genomes. We have examined the structural relationship amount the external glycoproteins from three specific human immunodeficiency viruses (HIF-1, HIV-2), three specific simian immunodeficiency viruses from macaques (SIVmac) and three specific SIV from African green monkeys (SIVagm) by peptide mapping. Differences among glycoproteins were most pronounced between HIV-1 and SIVmac, as well as HIV-2. Two specific glycoproteins from independent SIVagm isolates were closely related to HIV-1, whereas the glycoprotein from a third SIVagm isolate was more similar to those of SIVmac and HIV-2. Our analysis reflects the classification of primate immunodeficiency viruses into three groups, the HIV-2 and SIVmac viruses, the green monkey isolates and HIV-1.
Carrier experiments using Echo- and Influenza-viruses on denture basis resins and fragments of orthodontic appliances resulted in good and even very good virucidal effects of disinfectant sprays Desident and Fesia-sept. The application of the disinfectant as spray seem to be advantageous, but is not recommendable. The diverse causes of this conclusion are discussed and an alternative way is proposed.
Three disinfectant sprays (Arugeen, Desident and Fesia-sept) proved to be very efficient against pure cultures of aero bacteria species, Cand. albicans, saliva flora and entero- and influenza viruses. The methods included carrier experiments using denture basis resins, fragments of orthodontic appliances and screws (instead of instruments).
We report on five cases of mucosal atrophy of the gastric body, under the aspect of a polyposis: These polyps showed intact mucosa with abundant fundic glands and were situated in the diffuse atrophic mucosa of the gastric body. Four of these cases were manifestations of type A gastritis, in one case the lesion surrounded a peptic ulcer. Laboratory findings of serologically analysed cases with type A gastritis showed elevated parietal cell antibodies in all cases, two of three cases showed a high level of gastrin, the values for vitamin B12 showed different levels; no patients revealed antibodies against the intrinsic factor, and no patient had pernicious anemia. The family history revealed three cases with cancer of the stomach on one side of the parents. It is important to biopsy polyps and the flat mucosa separately in order to verify this form of atrophy of the gastric mucosa and to also exclude small polypous tumors of the mucosa. Observation of the number of polyps allows a control of the extent of the atrophy of the mucosa.
The reactivity of 38 murine strains to a synthetic analogue of bacterial lipoprotein, tripalmitoyl-pentapeptide (TPP), was tested and compared with the reactivity to lipopolysaccharide (LPS). These strains include common laboratory mice and H-2 recombinant inbred lines, as well as some newly bred lines originating from animals recently captured in different regions of Europe. All animals analysed were reactive to TPP and polyclonally activated to proliferation and immunoglobulin synthesis. Large differences in mitogen reactivities of various H-2 recombinant inbred strains suggest that MHC or closely linked gene products influence the reactivity to the LPS and TPP mitogens. By analysing the frequencies of precursor cells reactive to TPP or LPS and the isotype patterns obtained after stimulation, we demonstrated that both mitogens activate individual B cells in different ways.
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Nude mice bearing allotype Ighb on a BALB/c genetic background (= CB nu/nu) are nonresponders to alpha (1----3)dextran (Dex), in contrast to BALB/c or BALB/c nu/nu. Although CB nu/nu mice accept transplants of congenic BALB/c, or BALB nu/nu lymphocytes, as shown by the expression of donor allotype Igha, they are not permissive for a primary anti-Dex response by the grafted cells. BALB/c or BALB nu/nu cells, however, give a strong anti-Dex response when grafted onto irradiated CB nu/nu or CB 23 (Ighb) euthymic mice. A thymus-independent, radiation-sensitive suppressor cell population is postulated, which specifically hinders the anti-Dex response, and which is exhibited by strains bearing that portion of chromosome 12 which codes for CH allotype Ighb, not containing the germ-line anti-Dex V/D genes. The suppressive action of Ighb lymphocytes could be demonstrated directly in staggered co-transfer experiments.
Five patients with post-transfusion purpura (four due to Zw(a), one presumably due to HLA antibodies) were treated with intravenous immunoglobulin (IgG) at doses of 0.4 g per kg body weight. IgG therapy was immediately effective as indicated by cessation of bleeding and rise of platelet counts in four out of five cases.
Mouse milk cells were stained with rhodamine or fluorescein isothiocyanate and fed to young suckling mice. By visual examination of serial sections and by flow cytofluorometry, we were able to demonstrate directly the presence of these cells in peripheral tissues. It was estimated that at least 0.1% of the fed cells might infiltrate the young mouse, which is initially immunologically defenseless. This is in accordance with evidence from many sources for activity of maternally-derived lymphoid cells in young rodents.
The effect of Hydron burn wound dressing was evaluated using a standard Walker burned rat model (N = 156) and a rabbit ear wound model (N = 34). In both studies Hydron was administered only once in one group and changed twice weekly in another. Animals were predesignated as controls and for pathologic examination. Gross observations, including photographic documentation, and the pathologic analyses revealed no gross purulence or sepsis. No deaths occurred in the rabbit study. Of the 156 animals in the rat study only two died; a culture of the wounds revealed no sepsis. Statistical analyses revealed that in the rat study the once only application was significantly better at 7 days postburn than the twice weekly treatment and control groups. No significant differences among the treatment and control groups used in the rabbit study were revealed. The application of Hydron burn wound dressing did not adversely affect the wound healing.