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Helicobacter pylori infects the stomachs of nearly a half the human population, yet most infected individuals remain asymptomatic, which suggests that there is a host defense against this bacterium. Because H. pylori is rarely found in deeper portions of the gastric mucosa, where O-glycans are expressed that have terminal alpha1,4-linked N-acetylglucosamine, we tested whether these O-glycans might affect H. pylori growth. Here, we report that these O-glycans have antimicrobial activity against H. pylori, inhibiting its biosynthesis of cholesteryl-alpha-D-glucopyranoside, a major cell wall component. Thus, the unique O-glycans in gastric mucin appeared to function as a natural antibiotic, protecting the host from H. pylori infection.  相似文献   
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A plant-growth-promoting fungus (PGPF), Talaromyces sp. was isolated from an agricultural field in southwestern Japan. We found that this fungus emitted several terpenoid-like volatiles including β-caryophyllene. Then we investigated the effect of β-caryophyllene on promoting the growth and inducing resistance of Brassica campestris L. var. perviridis. The compound significantly enhanced the growth of seedlings and their resistance to Colletotrichum higginsianum. On the basis of these results, we discuss the role of β-caryophyllene in the activities of PGPF.  相似文献   
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Analysis of global positioning system data shows that the rate of crustal deformations in the Tokai region of Japan, a seismic gap area, changed over the past 18 months. Kalman filtering analysis shows aseismic slip on the plate boundary in the western Tokai region centered on Lake Hamana, adjacent to the anticipated Tokai earthquake source area. The cumulative moment magnitude reaches 6.7 in June 2002 with a relative slip increase northeast of Lake Haman from January 2002. An existence of aseismic slip in the western Tokai supports the hypothesis of a silent event as the cause of uplifting several days before the 1944 Tonankai earthquake.  相似文献   
156.
Malakoplakia is a rare form of chronic granulomatous inflammation in mammals, and usually affects the urinary tract in humans. In this report, we present a case of granulomatous nephritis consistent with malakoplakia in a 4-year-old male cynomolgus monkey. Gross examination showed that the kidney was markedly enlarged and adhered to the surrounding organs. Histology showed that there was diffuse interstitial infiltration of histiocytes with abundant foamy eosinophilic cytoplasm resembling von Hansemann cells, PAS-positive granular cytoplasm and occasional PAS- and iron-positive intracellular small inclusion bodies. Electron microscopy showed that these histiocytes contained abundant lysosomes and phagolysosomes but no obvious Michaelis-Gutmann bodies. Based on these findings, a diagnosis of granulomatous nephritis consistent with early malakoplakia was made. This is the first report in a monkey of a renal lesion consistent with malakoplakia.  相似文献   
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A spontaneously occurring subcutaneous mass in the left forelimb of a nine-year-old rabbit (Oryctolagus cuniculus) was examined histopathologically and immunohistochemically. Clinically, edema and hemorrhage were seen around the mass. No connection of the tumor mass to the appendicular skeleton was found. The tumor was arranged in a solid growth pattern and irregular bundles, and neoplastic cells were polygonal to spindle-shape. Osteoid (positive for osteocalcin) and multinucleated giant cells were diffusely or focally seen. Neoplastic cells were positive for vimentin, osterix and Ki-67, indicating the nature of osteoblasts with proliferating activity, but negative for α-smooth muscle actin, desmin or CD204. Based on these findings, a diagnosis of extraskeletal osteosarcoma was made, a very rare tumor both in laboratory and pet rabbits.  相似文献   
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We investigated the effect of oxidative stress induced by hydrogen peroxide (H2O2) on lipid peroxide (LPO) level and nuclear maturation in porcine oocytes cultured with or without cumulus cells. After 22 h of pre‐culture, oocytes with attached cumulus cells (COC group) or denuded oocytes (DO group) were cultured with H2O2, and intra‐oocyte H2O2 and LPO levels were quantitatively analyzed using immunofluorescence. This is the first report evaluating LPO levels in porcine oocytes. After H2O2 supplementation, the DO group showed severe accumulation of H2O2 and LPO in the oocytes. Similarly, while inhibition of progression of nuclear maturation was observed in both groups, the effect was more severe in the DO group. These results demonstrate that cumulus cells reduce the accumulation of H2O2 stress in oocytes. Furthermore, we attempted to reduce the oxidative stress by H2O2 with L‐carnitine, a H2O2 scavenger. L‐carnitine decreased H2O2 and LPO levels in the oocytes in both groups, and improvement in the progression of impaired nuclear maturation was observed. These effects were different by the presence of cumulus cells. Our results provide that L‐carnitine is useful for alleviating H2O2‐induced oxidative stress by reducing LPO levels and improving the progression of nuclear maturation.  相似文献   
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