Persistent infection of human lymphoid and myeloid cell lines with herpes simplex virus.

Herpes simplex virus (HSV) type 1 replicated and persisted in human T, B, and myeloid cell lines with different patterns of viral replication and various effects on cell growth. T cell line CEM supported the replication of HSV for over 400 days without detectable differences in cell growth as compared with uninfected cells. HSV persisted in B cell line NC37 and myeloid cell line K562 for up to 222 and 374 days, respectively, but led to a significant decrease in the number of viable cells by 7 weeks of infection. The average number of cells producing infectious virus was very low in these cell lines (range, 0.5 to 2.7+) compared with a larger proportion of cells exhibiting HSV antigens by immunofluorescence (range, 24 to 58%). In contrast, null cell line LAZ 221 failed to replicate HSV even though the viral infection led to a cessation of cell growth.     

Serum-induced chronic pancreatitis

Summary Clinical research into patients with idiopathic chronic pancreatitis points to a possible immunopathogenetic process in a number of cases.In order to examine the behaviour between the exocrine pancreas under the influence of anti-rat-pancreas immune serum produced in rabbits, a 1.00 ml immune serum is administered once a week over a maximum 26 week period into Wistar-rats by intraperitoneal injection. By electrone-microscopy a much reduced production of enzymes apparently takes place, though to differing extent. There is also destruction of the basal membrane of acinocytes; the production of interstitial oedema, the new formation of collagen fibres and the proliferation of connective tissue cells. Under a conventional light microscope the first changes become noticeable after 8-12 weeks of study. These take the form of localised cell decay, deterioration and lysis of acinocytes; and an increasing non-specific inflammation. There is also the new formation of connective tissue. After 20–26 weeks the exocrine pancreas is characterised by reduction of parenchyma, acino-ductal metaplasia, chronic inflammatory infiltrates of differing density, fibrous and irregular calibres of the smaller and larger ducts.The findings are almost identical to the structural changes of chronic idiopathic pancreatitis in human beings. The results support the view of an immuno-pathologic aetiology for human chronic idiopathic pancreatitis.Supported by Deutsche Forschungsgemeinschaft     

Electron microscopic studies of endocrine hyperplasia in duodenal adenomas in familial adenomatous polyposis

Summary Electron microscopical studies on endocrine cell hyperplasia of duodenal adenomas from five patients with familial adenomatous polyposis were performed. All the endocrine cell types normally found in the duodenal mucosa were identified. A constant feature was proliferation of duodenal-enterochromaffin cells but an increase in the number of all other endocrine cell types apart from pyloricgastrin cells and somatostatin cells, was also observed. Certain types of intestinal endocrine cells (the intestinal enterochromaffin cell and the glicentin cell) are rare cells in the normal duodenal mucosa. The finding of these cells may indicate increased biological aggressivity.     

Frequency of rpoB mutations inside and outside the cluster I region in rifampin-resistant clinical Mycobacterium tuberculosis isolates

The prevalence of recently described mutation V176F, located in the beginning of the rpoB gene and associated with rifampin resistance and the wild-type cluster I sequence, was determined by analyzing the distribution of rpoB mutations among 80 rifampin (RIF)-resistant Mycobacterium tuberculosis strains isolated in Germany during 1997. The most frequent rpoB mutations were changes in codon 456 (52 isolates, 65%), followed by changes in codon 441 (13 isolates, 16%) and codon 451 (11 isolates, 14%). The V176F mutation was detected in one isolate of the study population and in 5 of 18 RIF-resistant strains with no cluster I mutation from six previously published studies. In three isolates, a mixture of resistant and susceptible subpopulations (heteroresistance) prohibited the detection of rpoB mutations in the initial analysis; however, in these isolates, cluster I mutations could be verified after a passage on RIF-containing medium. IS6110 DNA fingerprinting of 76 strains revealed eight clusters comprising 27 strains with identical restriction fragment length polymorphism patterns that mainly also show identical rpoB mutations and identical or similar drug resistance patterns. In conclusion, our results indicate that the V176F mutation should be included in molecular tests for prediction of RIF resistance in M. tuberculosis. We further demonstrated that heteroresistance caused by a mixture of mycobacterial subpopulations with different susceptibilities to RIF may influence the sensitivity of molecular tests for detection of resistance.     

Fatal disseminated Trichoderma longibrachiatum infection in an adult bone marrow transplant patient: species identification and review of the literature

Trichoderma longibrachiatum was recovered from stool surveillance cultures and a perirectal ulcer biopsy specimen from a 29-year-old male who had received an allogeneic bone marrow transplant for acute lymphoblastic leukemia. The amphotericin B (2.0 microgram/ml) and itraconazole (1.0 microgram/ml) MICs for the organism were elevated. Therapy with these agents was unsuccessful, and the patient died on day 58 posttransplantation. At autopsy, histologic sections from the lungs, liver, brain, and intestinal wall showed infiltration by branching septate hyphae. Cultures were positive for Trichoderma longibrachiatum. While Trichoderma species have been recognized to be pathogenic in profoundly immunosuppressed hosts with increasing frequency, this is the first report of probable acquisition through the gastrointestinal tract. Salient features regarding the identification of molds in the Trichoderma longibrachiatum species aggregate are presented.     

Chromosome 8p deletions are associated with invasive tumor growth in urinary bladder cancer.

Alterations of chromosome 8, including deletions of 8p, occur frequently in many tumors. In this study, fluorescence in situ hybridization was used to study the relationship between 8p deletions, 8q gains, and phenotype in bladder cancer. Cells from 87 tumors were examined by dual-labeling fluorescence in situ hybridization with a centromere 8 probe (pJM12) and P1 probes for 8p22, 8p12, 8q12, and 8q24. Both 8p22 deletions and 8q24 gains were strongly associated with tumor phenotype. There was a marked difference in 8p22 deletions between noninvasive (pTa) tumors (3/33) and minimally invasive (pT1) tumors (8/19; P = 0.005) whereas there was no significant difference between pT1 and muscle-invasive (pT2-4) tumors (19/35; P = 0.3926). Six tumors with 8p22 deletion were examined at 8p12. Three of these tumors showed no 8p12 deletion, narrowing down the site of a putative tumor suppressor gene distal to 8p12. In one other case, there was a marked increase in 8p12 copy number (> 40 per cell; amplification), suggesting the presence of an oncogene involved in bladder cancer at 8p12. The marked difference in 8p22 deletions between noninvasive (pTa) and minimally invasive (pT1) tumors is consistent with a role of a putative tumor suppressor gene on 8p for development of invasive tumor phenotype.     

Separate and variably shaped chromosome arm domains are disclosed by chromosome arm painting in human cell nuclei

Fluorescence in situ hybridization (FISH) with microdissection probes from human chromosomes 3 and 6 was applied to visualize arm and subregional band domains in human amniotic fluid cell nuclei. Confocal laser scanning microscopy and quantitative three-dimensional image analysis showed a pronounced variability of p- and q-arm domain arrangements and shapes. Apparent intermingling of neighbouring arm domains was limited to the domain surface. Three-dimensional distance measurements with pter and qter probes supported a high variability of chromosome territory folding.     

Effect of sodium citrate on the rate of cholesterol esterification and on the formation of primary products of lipid peroxidation in human blood. Are these processes related?

In vitro experiments show that sodium citrate in a final concentration of 130 mM induces a 4- to 5-fold increase in the activity of lecithin-cholesterol acyltransferase. A parallel determination of the blood content of primary products of lipid peroxidation reveals a 20–30% decrease in diene and triene conjugates and lipid hydroperoxides. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 9, pp. 323–325, September, 1995 Presented by A. N. Klimov, Member of the Russian Academy of Medical Sciences     

Histochemical Distribution of Carbonic Anhydrase After Ligation of the Pancreatic Duct

The distribution of carbonic anhydrase in the exocrine pancreas of the rat has been examined during the first 3 weeks after duct ligation. The normal pattern of positive reaction in ducts, centroacinar cells and capillaries changed, by the end of the first week, to one in which all the cells in the dilated ducts showed the enzyme. This situation persisted through the third week. By electron microscopy, the enzyme was found on the apical membranes of ductular, centroacinar and acinar cells, as well as on the surface membranes of the modified cells seen at 1 week. The significance of these findings with respect to function and cell origin is discussed.     

Differences in cytokine secretion by intestinal mononuclear cells, peripheral blood monocytes and alveolar macrophages from HIV-infected patients.

Mononuclear cells of the lamina propria (LpMNC), isolated from endoscopically taken biopsies of the large bowel from AIDS patients, were analysed for their ability to secrete tumour necrosis factor-alpha (TNF-alpha), IL-1 beta and IL-6. Stimulation of LpMNC from normal controls with pokeweed mitogen (PWM) led to a time- and dose-dependent enhancement of TNF-alpha, IL-1 beta and IL-6 secretion. In contrast, PWM stimulation of LpMNC from AIDS patients resulted in only a small increase in TNF-alpha release. Constitutive secretion of IL-1 beta and IL-6 in these patients was already increased to the concentration range of stimulated cells from normal controls and could not be further increased, probably due to maximal in vivo stimulation. Secretion of TNF-alpha, IL-1 beta and IL-6 by peripheral blood monocytes (PBM) and alveolar macrophages from AIDS patients was elevated with or without stimulation compared with normal controls. Obviously, the regulation of TNF-alpha secretion is dependent on the microenvironment. Since it is known that interferon-gamma (IFN-gamma) may induce the production of TNF-alpha, the secretion of this cytokine was examined. Release of IFN-gamma was constitutively and under stimulation lowered in LpMNC from AIDS patients compared with normal controls. Addition of IFN-gamma to LpMNC did not result in enhanced TNF-alpha secretion. Our data indicate a defective function of intestinal mononuclear cells in AIDS patients as shown by the diminished TNF-alpha secretion.