Primary gastric apoptosis-rich T-cell lymphoma co-expressing CD4, CD8, and cytotoxic molecules

In contrast to primary gastric lymphomas of B-cell type, little is known about primary gastric T-cell lymphomas. We describe three cases with remarkably similar features: diffuse growth, epitheliotropism, medium too large cell size, high apoptotic rates, and a CD3+, CD4+, CD8+, CD45RO+ immunophenotype. Clonal TCRγ gene rearrangement was shown in two cases. Epstein-Barr virus infection was excluded in two cases. Taking advantage of fresh-frozen material, we analyzed two cases further, revealing CD5–, CD16+, CD56–, CD57–, CD25+, CD30+, CD103 (αEβ7)+, bcl-2 protein+, CD95+, CD95 ligand(L)–. CD95L, however, was detected in histiocytic and fibroblastoid by stander cells. The lymphomas expressed granzyme B, perforin, and the TIA-1 antigen in various combinations. All three cases had a very unfavorable clinical course characterized by local recurrence and/or dissemination to other epithelial sites, leading to death within 6–12 months after the initial diagnosis despite surgery and aggressive antineoplastic treatment. These data suggest a novel variant of peripheral T-cell lymphoma operationally characterized as primary gastric, apoptosis-rich, CD103+, EBV-, T-cell lymphoma co-expressing CD4, CD8, CD16 and cytotoxic molecules. Received: 20 August 1999 / Accepted: 2 November 1999     

How to use Heidenhains azan staining in insects

A newly modified, histochemical Azan staining procedure which was originally designed by Heidenhain was adapted for insects. This led to new insights in the structure of the central nervous system of flies. The somata are weakly stained with a red colored nucleus. Neuroglial regions are stained intensively red. Some undefined portions of the neuronal tracts seem to be uncolored but the unstained profiles are still visible. The other portions contain blue colored cells. These differences may be due to the cells' different monoamine content. Using this method new morphological substructures could be identified in both the mushroom bodies and the central complex of the central nervous system that do not seem to be described earlier.     

A murine TSPY

Sequences homologous to human and bovine TSPY were isolated from M. musculus testicular cDNA, and a nearly full-length gene was polymerase chain reaction (PCR) amplified from mouse genomic DNA. This gene is apparently non-functional. Contrary to the situation encountered in species along the primate and artiodactyl lineages, in which TSPY is moderately repetitive, murine Tspy appears to be single copy. Murine Tspy is located on Yp, i.e. in the same syntenic group as in man. Sequence comparisons of murine, human and bovine TSPY exons suggest that TSPY became non-functional during rodent evolution.     

Hyperplasia and tumors of the parathyroid glands

Zusammenfassung Die verschiedenen Formen des Hyperparathyreoidismus werden überwiegend von Hyperplasien und Adenomen der Nebenschilddrüsen verursacht. Während früher die Diagnose des Pathologen (meist schon im intraoperativen Gefrierschnitt) für das chirurgische Vorgehen maßgebend war, wird das Operationsausmaß heute überwiegend durch die wesentlich verbesserte präoperative Diagnostik bestimmt (bildgebende Verfahren) und durch den nach der Entfernung der vergrößerten Nebenschilddrüse(n) intraoperativ gemessenen Abfall des Parathormons kontrolliert. Nichtsdestotrotz sollte dem Pathologen die morphologische Differenzialdiagnose der Hyperplasie, des Adenoms und Karzinoms der Nebenschilddrüsen geläufig sein.

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HLA Antigens in 16 Families with Xeroderma Pigmentosum

Xeroderma pigmentosum is an autosomal recessive disease. HLA-A and -B typing was performed on peripheral blood lymphocytes and platelets. Sixteen Tunisian families were typed with 37 patients and 108 relatives. Genetic transmission of the disease and of the HLA system seemed to be independent in this study. Comparison of HLA gene frequencies between (unrelated) parents of patients and a control population showed no difference, proving that there is no clear association in populations between deleterious XP genes and a particular HLA gene. However, an excess of identical HLA among pairs of diseased siblings would suggest that the disease is polymorphic and a form of the XP could be linked to HLA.     

The role of accessory cells and T cell-growth factor in induction of cytotoxic T lymphocytes against herpes simplex virus antigens.

The roles of accessory cells and T cell-growth factor (TCGF) in the in vivo induction of herpes simplex type 1 (HSV) specific cytotoxic lymphocytes (CTL) were evaluated. Spleen cells from animals infected with HSV 4-6 weeks previously were depleted of adherent cells by passage over Sephadex G10. Unlike intact cells, such depleted spleen cells failed to respond by producing H-2 restricted virus-specific CTL upon culture for 5 days with infectious HSV. The CTL response could be restored either by adding normal genetically compatible peritoneal cells as accessory cells or by the addition of TCGF. To obtain optimum restoration accessory cells needed to be added soon after culture initiation but with TCGF addition, partial restoration was evident when added as late as 72 hr after culture. TCGF also permitted intact spleen cells to respond to heat-inactivated virus. The results are interpreted to indicate that accessory cells are essentially required for the presentation of virus to specific helper cells with such cells responding by the production of TCGF. The results also indicate that certain forms of virus may trigger the response of CTL precursors but not the response of helper cells.     

Inhibition of the insulin receptor kinase phosphorylation by nitric oxide: functional and structural aspects

Previous studies on cultured skeletal muscle cells have indicated that the insulin-induced expression of GLUT4 transporter protein is inhibited by nitric oxide (NO). Therefore, we determined the effect of NO on the insulin-induced autophosphorylation of the insulin receptor kinase (IRK), i.e., the first step in the insulin-mediated signal transduction pathway. The experiments showed that the insulin-induced autophosphorylation of the insulin receptor beta-chain is strongly inhibited by the NO donors 1,1-diethyl-2-hydroxy-2-nitrosohydrazine (DEA-NO) or S-nitroso-N-acetylpenicillamine (SNAP). The inhibitory effect was ameliorated in cells depleted of glutathione (GSH), suggesting the possibility that S-nitroso-glutathione may operate as an intermediate NO donor. Complementary experiments with different Cys --> Ala mutant proteins showed, surprisingly, that all mutant proteins were inhibited by DEA-NO. Three-dimensional models of the nonphosphorylated IR beta-chain nitrosylated at the accessible cysteine residues 1056, 1138, 1234, or 1245 revealed that derivatization of any of these four cysteine residues leads essentially to the same structural changes of the IRK domain. These changes involve a movement of the amino-terminal lobe against the carboxy-terminal lobe in a direction opposite to the direction of the "lobe closure" that was previously proposed to facilitate the accessibility for ATP and the expression of catalytic activity. Our findings suggest that the occurrence of several functionally relevant cysteine residues in distinct regions of the IRK protein increases the probability of regulatory redox interactions and thus the redox sensitivity of the IRK.     

The sensitivity of posturographic parameters to acquisition settings

The objective of this study was to evaluate the sensitivity of posturographic parameters (PP) to changes in acquisition settings. A group of eight young adults underwent a set of typical orthostatic posture trials, and selected PP were then calculated from a set of centre of pressure (CoP) displacement time series obtained by applying different cut-off frequencies to the same set of raw data. Four PP out of 11 showed significant changes with respect to cut-off frequency. Statistical mechanics parameters exhibited smaller sensitivity than summary measures. On the basis of the results obtained, a proposal for a standard cut-off frequency and a sampling rate value is embodied in the paper together with some suggestions on measurement settings, with a view to standardized use of instrumentation for quantitative analysis in orthostatic posturography.     

Allergologic exploration of germins and germin-like proteins,a new class of plant allergens

BACKGROUND: Germins and the related germin-like proteins (GLPs) are glycoproteins expressed in many plants in response to biotic and abiotic stress. To test the potential impact of germins and GLPs, recombinant germin from Triticum aestivum (tGermin) and GLPs from Arabidopsis thaliana (tGLP), both produced in transformed tobacco plants, were used. METHODS: Sera from 82 patients with type I allergy to birch, grass or mugwort pollen and/or wheat were tested in immunoblot for IgE binding to tGermin and tGLP, and the IgE reactivity after chemical and enzymatic deglycosylation was analysed. The biological activity of tGermin and tGLP was determined in a histamine release assay and in skin prick testing (SPT). RESULTS: In an immunoblotting assay, 24 out of 82 tested sera (29.26%) from allergic patients showed IgE-binding to tGermin, and 18 of these sera (21.95%) displayed also IgE-binding to tGLP. The deglycosylation experiments indicated that glycan moieties contribute significantly to the IgE-binding of tGermin and tGLP. Both tGermins and tGLP induced specifically histamine release in an in vitro assay as well as in SPT. CONCLUSION: Our in vitro and in vivo findings demonstrate that germin and GLPs are capable to bind IgE most likely via carbohydrate determinants, and represent allergenic molecules.