Abrogation of in vitro suppression of human immunodeficiency virus type 1 (HIV-1) replication mediated by CD8+ T lymphocytes of asymptomatic HIV-1 carriers by staphylococcal enterotoxin B and phorbol esters through induction of tumor necrosis factor alpha.

CD8+ T lymphocytes of asymptomatic human immunodeficiency virus type 1 (HIV-1) carriers (AC) suppress HIV-1 replication in vitro. Failure of host defense mechanisms and increased virus proliferation are associated with disease progression. The exact mechanisms inducing these changes at the advanced stage of the disease are still obscure. In this study, we searched for experimental conditions favoring the abrogation of the suppression of viral replication in peripheral blood mononuclear cells (PBMC) of AC by using various pharmacological and biological probes modifying cell activation. Among such agents, staphylococcal enterotoxin B (SEB) and phorbol 12-myristate 13-acetate (PMA) markedly increased otherwise low levels of HIV-1 replication in cultures of phytohemagglutinin-stimulated AC PBMC following in vitro HIV-1 LAI infection. A similar but less pronounced virus induction was also observed in macrophage-tropic HIV-1. Individual pretreatment of CD4+ and CD8+ PBMC fractions with these agents caused a reduction in CD8+ cell proliferation and enhanced HIV-1 replication in CD4+ cells. SEB- and PMA-mediated augmentation of HIV-1 replication in AC PBMC was significantly blocked by neutralizing antibody to tumor necrosis factor-alpha (TNF-alpha), although recombinant TNF-alpha alone failed to reproduce the effects of SEB or PMA. Our results suggest that the induction of TNF-alpha may be one of the mechanisms that overcomes the CD8+-induced suppression of HIV-1 replication in AC and that it may induce HIV-1 replication.     

Cytochromes in the Cultured Mycobiont of a Lichen, Cladonia vulcani Sav

Cytochromes in a cultured cells of the mycobiont of Cladoniavulcani Sav. were studied, b-and c-type cytochromes and aa₃-typecytochrome c oxidase were found in the membrane fraction, whileb- and c-type cytochromes were found in the soluble fraction.Soluble cytochrome c-549.5 was purified, and some of its molecularproperties were determined. (Received June 27, 1994; Accepted October 3, 1994)     

Intraosseous inflammatory myofibroblastic tumor of the mandible with a novel <Emphasis Type="Italic">ATIC-ALK</Emphasis> fusion mutation: a case report

Background

Inflammatory myofibroblastic tumor (IMT) is a rare low-grade malignant neoplasm with a predilection for children and young adults, and typically arises in the lung, abdominopelvic region, and retroperitoneum. IMTs in the maxillofacial region are extreme rare. Approximately 50% of IMT harbor rearrangements of the anaplastic lymphoma kinase (ALK) gene at 2p23 with various fusion partners.

Case presentation

We herein report a case of intraosseous IMT of the mandible with a novel ATIC-ALK fusion. Tooth 43 did not erupt after the loss of tooth 83 in an 11-year-old girl with no previous history of trauma. Panoramic tomography showed a unilocular radiolucent lesion in the right anterior mandible resorbing the root of tooth 42 and the medial side of the root of tooth 44. Computed tomography revealed a well- circumscribed 3-cm osteolytic lesion of the right anterior mandible eroding the buccal cortical plate. The entire lesion was curetted out. A histopathological examination revealed the proliferation of plump spindle cells with a storiform architecture and lymphocytes scattered around spindle cells. The spindle cells showed diffuse cytoplasmic staining for ALK by immunohistochemistry. A fluorescence in situ hybridization analysis revealed the translocation of a part of the ALK gene locus at chromosome 2p23. A rapid amplification of cDNA ends analysis confirmed the rearrangement of ALK and identified ATIC as a partner of this ALK fusion mutant.

Conclusion

To the best of our knowledge, this is the first case of intraosseous IMT of the mandible with a novel ATIC-ALK fusion. We also herein reviewed similar tumors reported in the literature.

     

Fluorescence in situ hybridization using 16S rRNA-targeted oligonucleotides reveals localization of methanogens and selected uncultured bacteria in mesophilic and thermophilic sludge granules

16S rRNA-targeted in situ hybridization combined with confocal laser scanning microscopy was used to elucidate the spatial distribution of microbes within two types of methanogenic granular sludge, mesophilic (35 degrees C) and thermophilic (55 degrees C), in upflow anaerobic sludge blanket reactors fed with sucrose-, acetate-, and propionate-based artificial wastewater. The spatial organization of the microbes was visualized in thin sections of the granules by using fluorescent oligonucleotide probes specific to several phylogenetic groups of microbes. In situ hybridization with archaeal- and bacterial-domain probes within granule sections clearly showed that both mesophilic and thermophilic granules had layered structures and that the outer layer harbored mainly bacterial cells while the inner layer consisted mainly of archaeal cells. Methanosaeta-, Methanobacterium-, Methanospirillum-, and Methanosarcina-like cells were detected with oligonucleotide probes specific for the different groups of methanogens, and they were found to be localized inside the granules, in both types of which dominant methanogens were members of the genus Methanosaeta. For specific detection of bacteria which were previously detected by whole-microbial-community 16S ribosomal DNA (rDNA)-cloning analysis (Y. Sekiguchi, Y. Kamagata, K. Syutsubo, A. Ohashi, H. Harada, and K. Nakamura, Microbiology 144:2655-2665, 1998) we designed probes specific for clonal 16S rDNAs related to unidentified green nonsulfur bacteria and clones related to Syntrophobacter species. The probe designed for the cluster closely related to Syntrophobacter species hybridized with coccoid cells in the inner layer of the mesophilic granule sections. The probe for the unidentified bacteria which were clustered with the green nonsulfur bacteria detected filamentous cells in the outermost layer of the thermophilic sludge granule sections. These results revealed the spatial organizations of methanogens and uncultivated bacteria and their in situ morphologies and metabolic functions in both mesophilic and thermophilic granular sludges.     

Ethylene induced shikonin biosynthesis in shoot culture of Lithospermum erythrorhizon.

Lithospermum erythrorhizon shoots, cultured on phytohormone-free Murashige and Skoog solid medium, produced shikonin derivatives, whereas shoots cultured in well-ventilated petri dishes, produced small amount. Analysis by gas chromatography revealed the presence of ethylene in non-ventilated petri dishes where the shoots, producing shikonin derivatives, were cultured. Therefore, the possible involvement of ethylene in shikonin biosynthesis of shoot cultures was investigated. Treatment of ethylene or the ethylene precursor, 1-aminocyclopropane-1-carboxylic acid, resulted in increasing shikonin derivatives contents in cultured shoots. Silver ion, an ethylene-response inhibitor, or aminoethoxyvinylglycine, an ethylene biosynthesis inhibitor, decreased production of shikonin derivatives in cultured shoots. Our results indicate that ethylene is one of the regulatory elements of shikonin biosynthesis in L. erythrorhizon shoot culture.     

Constitutive Expression of Stress-Inducible Genes, Including Pathogenesis-Related 1 Protein Gene in a Transgenic Interspecific Hybrid of Nicotiana glutinosa x Nicotiana debneyi

Constitutive expression of a type of stress-inducible proteinsincluding pathogenesisrelated (PR) 1 protein and ubiquitin-relatedprotein in an interspecific hybrid of Nicotiana glutinosa xNicotiana debneyi was noted. In the two parental species andin tobacco, these proteins are not expressed in healthy plantsbut they are induced by stresses such as the formation of locallesions after viral infection and treatment of salicylic acid.A second type of stress-inducible genes, such as the genes forbasic ß-1,3-glucanase and putative proteinase inhibitorwere regulated normally, and were not expressed constitutivelyin the hybrid. In the transgenic hybrid, into which a chimericgene consisting of 5' upstream of tobacco PRla gene and ß-glucuronidase(GUS) gene was introduced, very high GUS activity was expressedconstitutively even at healthy state. An abnormal response bythis hybrid to plant hormones was also noted. A possible mechanismfor the unregulated expression of the stress-inducible genesin the interspecific hybrid is discussed. (Received September 13, 1991; Accepted December 27, 1991)     

Expression of liver X receptor alpha in rat fetal tissues at different developmental stages.

The liver X receptor (LXR) is a nuclear receptor that acts as a sterol sensor and metabolic regulator of cholesterol and lipid homeostasis. Using a novel LXRalpha-specific antibody for immunohistochemistry, we evaluated cellular expression of LXRalpha in fetal rat tissues. In the fetal liver, LXRalpha-positive macrophages appeared at 12 days and their number peaked at 18 days of gestation. In contrast, hepatocytes expressed LXRalpha during the later stage of gestation, suggesting the functional development of the liver during ontogeny. Later, macrophages in spleen and thymus expressed LXRalpha, and some mononuclear cells in the vascular lumen compatible to primitive/fetal macrophages in the fetal circulation were found to express LXRalpha. In vitro, rat monocytes did not express LXRalpha, but monocyte-derived macrophages cultured in the presence of macrophage-colony stimulating factor revealed the distinct expression of LXRalpha in nucleoli. These findings suggest that LXRalpha plays a role in the differentiation of fetal macrophages, particularly hepatic macrophages, in rat development.     

Comparative hypocholesterolemic effects of five animal oils in cholesterol-fed rats

The hypocholesterolemic efficacy of various animal oils was compared in rats given a cholesterol-enriched diet. After acclimatization for one week, male F344 DuCrj rats (8 weeks of age) that had been fed with a conventional diet were assigned to diets containing 5% of oil from emu (Dromaius), Japanese Sika deer (Cervus nippon yesoensis, Heude), sardine, beef tallow, or lard with 0.5% cholesterol for 6 weeks. After this feeding period, the concentrations of serum total cholesterol and of very-low-density lipoprotein + intermediate-density lipoprotein + low-density lipoprotein-cholesterol in the sardine oil group were significantly lower than those in the other groups. The serum high-density lipoprotein-cholesterol concentration in the Japanese Sika deer oil group was significantly higher than that in the other groups. The atherosclerotic index and liver cholesterol concentration in the sardine oil and Japanese Sika deer oil groups were significantly lower than those in the other groups. The fecal cholesterol excretion by the Japanese Sika deer oil group was significantly higher than that of the other groups, except for the sardine oil group, and the fecal bile acid excretion by the sardine oil group was significantly higher than that of the other groups, except for the lard group. These results suggest that Japanese Sika deer oil reduced the atherosclerotic index and liver cholesterol concentration in the presence of excess cholesterol in the diet as well as sardine oil did by increasing the excretion of cholesterol from the intestines of rats.