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Isam A. Mohamed Ahmed Jiro Arima Tsuyoshi Ichiyanagi Emi Sakuno Nobuhiro Mori 《World journal of microbiology & biotechnology》2010,26(8):1455-1464
Soil isolates, identified as Pseudomonas sp. strain A9 and Pseudomonas sp. strain B9b (based on the phenotypic features and phylogenetic analysis) were found to degrade homocholine aerobically.
Morphological characterization using the optical microscope under light and phase contrast conditions showed that cells of
strain A9 formed short rods measuring approximately 0.5–1 × 1.5–2.0 μm in size while those of B9b formed long rods of 0.5–1 × 2.5–3.0 μm
during the early growth phase on both nutrient broth and basal-homocholine (basal-HC) media. Strain A9 was able to grow on
basal-HC medium at a wide range of temperatures (4–41°C) whereas strain B9b was not able to grow at either 4 or 41°C. Comparative
16S rRNA sequencing studies indicated that strain A9 fell into the Pseudomonas putida subclade whereas strain B9b located in Pseudomonas fulva subclade. Washed cells of strains A9 and B9b degraded homocholine completely within 6 h with concomitant formation of several
metabolites. Analysis of the metabolites by capillary electrophoresis, fast atom bombardment–mass spectrometry, and gas chromatography–mass
spectrometry, showed trimethylamine (TMA) as the major metabolite beside β-alanine betaine and trimethylaminopropionaldehyde.
Therefore, the possible degradation pathway of homocholine in the isolated strains is through successive oxidation of the
alcohol group (–OH) to aldehyde (–CHO) and acid (–COOH), and thereafter the cleavage of β-alanine betaine C–N bonds yielding
trimethylamine and an alkyl chain. 相似文献
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We report the first case of a posterior mediastinal granular cell tumor initially diagnosed on cytologic material obtained via endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) in a 51-year-old male with a prior history of colon cancer. Aspirates obtained were cellular and composed of polygonal cells with abundant granular cytoplasm and small, round dark nuclei. An immunoperoxidase stain performed on the cell block for antibodies to S-100 protein showed strong, diffuse staining of the cytoplasmic granules. Electron microscopy performed on the cell block revealed numerous cytoplasmic lysosomes. This is the first case report in the English literature of a definitive preoperative diagnosis of a mediastinal granular cell tumor utilizing material obtained via EUS-FNA. 相似文献
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Testicular immune privilege promotes transplantation tolerance by altering the balance between memory and regulatory T cells 总被引:10,自引:0,他引:10
Nasr IW Wang Y Gao G Deng S Diggs L Rothstein DM Tellides G Lakkis FG Dai Z 《Journal of immunology (Baltimore, Md. : 1950)》2005,174(10):6161-6168
Immune responses are suppressed in immunologically privileged sites, which may provide a unique opportunity to prolong allograft survival. However, it is unknown whether testicular immune privilege promotes transplantation tolerance. Mechanisms underlying immune privilege are also not well understood. Here we found that islet transplantation in the testis, an immunologically privileged site, generates much less memory CD8(+) T cells but induces more Ag-specific CD4(+)CD25(+) regulatory T cells than in a conventional site. These CD4(+)CD25(+) cells exhibited the suppression of alloimmune responses in vivo and in vitro. Despite the immune regulation, intratesticular islet allografts all were rejected within 42 days after transplantation although they survived longer than renal subcapsular islet allografts. However, blocking CD40/CD40L costimulation induced the tolerance of intratesticular, but not renal subcapsular, islet allografts. Tolerance to intratesticular islet allografts spread to skin allografts in the non-privileged sites. Either transfer of memory CD8(+) T cells or deletion of CD25(+) T cells in vivo broke islet allograft tolerance. Thus, transplantation tolerance requires both costimulatory blockade, which suppresses acute allograft rejection, and a favorable balance between memory and regulatory T cells that could favorably prevent late allograft failure. These findings reveal novel mechanisms of immune privilege and provide direct evidence that testicular immune privilege fosters the induction of transplantation tolerance to allografts in both immunologically privileged and non-privileged sites. 相似文献
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Laura Fernández-Bertolín Joaquim Mullol Mireya Fuentes-Prado Jordi Roca-Ferrer Isam Alobid César Picado Laura Pujols 《PloS one》2015,10(5)
BackgroundChronic rhinosinusitis with nasal polyps (CRSwNP) is a chronic inflammatory disease of the upper airways frequently associated with asthma. Bacterial infection is a feature of CRSwNP that can aggravate the disease and the response to glucocorticoid treatment.ObjectiveWe examined whether the bacterial product lipopolysaccharide (LPS) reduces glucocorticoid receptor (GR) function in control nasal mucosa (NM) fibroblasts and in nasal polyp (NP) fibroblasts from patients with CRSwNP and asthma.MethodsNP (n = 12) and NM fibroblasts (n = 10) were in vitro pre-incubated with LPS (24 hours) prior to the addition of dexamethasone. Cytokine/chemokine secretion was measured by ELISA and Cytometric Bead Array. GRα, GRβ, mitogen-activated protein-kinase phosphatase-1 (MKP-1) and glucocorticoid-induced leucine zipper (GILZ) expression was measured by RT-PCR and immunoblotting, GRα nuclear translocation by immunocytochemistry, and GRβ localization by immunoblotting. The role of MKP-1 and GILZ on dexamethasone-mediated cytokine inhibition was analyzed by small interfering RNA silencing.ResultsPre-incubation of nasal fibroblasts with LPS enhanced the secretion of IL-6, CXCL8, RANTES, and GM-CSF induced by FBS. FBS-induced CXCL8 secretion was higher in NP than in NM fibroblasts. LPS effects on IL-6 and CXCL8 were mediated via activation of p38α/β MAPK and IKK/NF-κB pathways. Additionally, LPS pre-incubation: 1) reduced dexamethasone’s capacity to inhibit FBS-induced IL-6, CXCL8 and RANTES, 2) reduced dexamethasone-induced GRα nuclear translocation (only in NM fibroblasts), 3) did not alter GRα/GRβ expression, 4) decreased GILZ expression, and 5) did not affect dexamethasone’s capacity to induce MKP-1 and GILZ expression. MKP-1 knockdown reduced dexamethasone’s capacity to suppress FBS-induced CXCL8 release.ConclusionThe bacterial product LPS negatively affects GR function in control NM and NP fibroblasts by interfering with the capacity of the activated receptor to inhibit the production of pro-inflammatory mediators. This study contributes to the understanding of how bacterial infection of the upper airways may limit the efficacy of glucocorticoid treatment. 相似文献
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Suspended solids in and turbidity of runoff from green roofs 总被引:1,自引:0,他引:1
Green roof technology is used to reduce the quantity of stormwater runoff, but questions remain regarding its impact on quality. This study analyzed the total suspended solids (TSS) in and the turbidity of runoff from green roof growth media mixed with composted pine bark in an indoor pot study. The results showed that there were elevated levels of TSS and turbidity in the runoff that decreased over time for all growth media. Both TSS and turbidity are affected by the type of growth media. Lava and haydite had higher mean TSS and mean turbidity than arkalyte and bottom ash. Vegetation reduced the mean turbidity and mean TSS of the first flush by an average of 53% and 63%, respectively, but generally had no statistically significant effect thereafter. The results indicate that the media, rather than the vegetation, has a greater effect on TSS and turbidity in the runoff In areas with stringent water quality regulations for stormwater runoff from developed sites, media selection may be an important consideration. It may also be necessary in these regions to ensure that the roof is planted prior to receiving rainfall to minimize the first flush effect and that any irrigation does not result in runoff. 相似文献
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Khalid A Enan Hanna Rennert Ali M El-Eragi Abdel Rahim M El Hussein Isam M Elkhidir 《Virology journal》2011,8(1):222