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Kanzaki H Uedo N Ishihara R Nagai K Matsui F Ohta T Hanafusa M Hanaoka N Takeuchi Y Higashino K Iishi H Tomita Y Tatsuta M Yamamoto K 《Helicobacter》2012,17(3):224-231
Background: Barium radiographic studies have suggested the importance of evaluating areae gastricae pattern for the diagnosis of gastritis. Significance of endoscopic appearance of areae gastricae in the diagnosis of chronic atrophic fundic gastritis (CAFG) was investigated by image‐enhanced endoscopy. Materials and Methods: Endoscopic images of the corpus lesser curvature were studied in 50 patients with CAFG. Extent of CAFG was evaluated with autofluorescence imaging endoscopy. The areae gastricae pattern was evaluated with 0.2% indigo carmine chromoendoscopy. Micro‐mucosal structure was examined with magnifying chromoendoscopy and narrow band imaging. Results: In patients with small extent of CAFG, polygonal areae gastricae separated by a narrow intervening part of areae gastricae was observed, whereas in patients with wide extent of CAFG, the size of the areae gastricae decreased and the width of the intervening part of areae gastricae increased (p < 0.001). Most areae gastricae showed a foveola‐type micro‐mucosal structure (82.7%), while intervening part of areae gastricae had a groove‐type structure (98.0%, p < 0.001). Groove‐type mucosa had a higher grade of atrophy (p < 0.001) and intestinal metaplasia (p < 0.001) compared with foveola type. Conclusions: As extent of CAFG widened, multifocal groove‐type mucosa that had high‐grade atrophy and intestinal metaplasia developed among areae gastricae and increased along the intervening part of areae gastricae. Our observations facilitate our understanding of the development and progression of CAFG. 相似文献
104.
Jian Huang Kazuhide Nara Chunlan Lian Kun Zong Kejian Peng Shengguo Xue Zhenguo Shen 《Mycorrhiza》2012,22(8):589-602
To advance our understanding of ectomycorrhizal fungal communities in mining areas, the diversity and composition of ectomycorrhizal fungi associated with Masson pine (Pinus massoniana Lamb.) and soil chemistry were investigated in Taolin lead–zinc (Pb–Zn) mine tailings (TLT), two fragmented forest patches in a Huayuan Pb–Zn mineland (HY1 and HY2), and a non-polluted forest in Taolin in central south China. Ectomycorrhizal fungal species were identified by morphotyping and sequence analyses of the internally transcribed spacer regions of ribosomal DNA. The two study sites in the Huayuan mineland (HY1 and HY2) were significantly different in soil Pb, Zn, and cadmium (Cd) concentrations, but no significant difference was observed in ectomycorrhizal colonization, ectomycorrhizal fungal richness, diversity, or rank–abundance. In addition, the similarity of ectomycorrhizal fungal communities between HY1 and HY2 was quite high (S?rensen similarity index?=?0.47). Thus, the concentration of heavy metals may not be determining factors in the structure of these communities. In the tailings, however, significantly lower ectomycorrhizal colonization and ectomycorrhizal fungal richness were observed. The amounts of Pb and Zn in the tailing sand were higher than the non-polluted forest but far lower than in HY1. Thus, these heavy metals did not account for the reduced colonization and ectomycorrhizal fungal richness in TLT. The ectomycorrhizal fungal community in TLT was dominated by four pioneer species (Rhizopogon buenoi, Tomentella ellisii, Inocybe curvipes, and Suillus granulatus), which collectively accounted for 93.2?% of root tip colonization. The immature soil conditions in tailing (low N and P, sand texture, and lack of organic matter) may only allow certain pioneer ectomycorrhizal fungal species to colonize the site. When soil samples from four sites were combined, we found that the occurrences of major ectomycorrhizal fungal taxa were not clearly related to the concentrations of Pb, Zn, and Cd. In conclusion, our results suggest that ectomycorrhizal fungal communities in mining areas are not necessarily affected by heavy metals themselves but could be largely determined by soil maturity. 相似文献
105.
Okuda KS Astin JW Misa JP Flores MV Crosier KE Crosier PS 《Development (Cambridge, England)》2012,139(13):2381-2391
We have generated novel transgenic lines that brightly mark the lymphatic system of zebrafish using the lyve1 promoter. Facilitated by these new transgenic lines, we generated a map of zebrafish lymphatic development up to 15 days post-fertilisation and discovered three previously uncharacterised lymphatic vessel networks: the facial lymphatics, the lateral lymphatics and the intestinal lymphatics. We show that a facial lymphatic vessel, termed the lateral facial lymphatic, develops through a novel developmental mechanism, which initially involves vessel growth through a single vascular sprout followed by the recruitment of lymphangioblasts to the vascular tip. Unlike the lymphangioblasts that form the thoracic duct, the lymphangioblasts that contribute to the lateral facial lymphatic vessel originate from a number of different blood vessels. Our work highlights the additional complexity of lymphatic vessel development in the zebrafish that may increase its versatility as a model of lymphangiogenesis. 相似文献
106.
Background
Babesia bovis is an apicomplexan intraerythrocytic protozoan parasite that induces babesiosis in cattle after transmission by ticks. During specific stages of the apicomplexan parasite lifecycle, such as the sporozoites of Plasmodium falciparum and tachyzoites of Toxoplasma gondii, host cells are targeted for invasion using a unique, active process termed “gliding motility”. However, it is not thoroughly understood how the merozoites of B. bovis target and invade host red blood cells (RBCs), and gliding motility has so far not been observed in the parasite.Methodology/Principal Findings
Gliding motility of B. bovis merozoites was revealed by time-lapse video microscopy. The recorded images revealed that the process included egress of the merozoites from the infected RBC, gliding motility, and subsequent invasion into new RBCs. The gliding motility of B. bovis merozoites was similar to the helical gliding of Toxoplasma tachyzoites. The trails left by the merozoites were detected by indirect immunofluorescence assay using antiserum against B. bovis merozoite surface antigen 1. Inhibition of gliding motility by actin filament polymerization or depolymerization indicated that the gliding motility was driven by actomyosin dependent process. In addition, we revealed the timing of breakdown of the parasitophorous vacuole. Time-lapse image analysis of membrane-stained bovine RBCs showed formation and breakdown of the parasitophorous vacuole within ten minutes of invasion.Conclusions/Significance
This is the first report of the gliding motility of B. bovis. Since merozoites of Plasmodium parasites do not glide on a substrate, the gliding motility of B. bovis merozoites is a notable finding. 相似文献107.
Misu H Ishikura K Kurita S Takeshita Y Ota T Saito Y Takahashi K Kaneko S Takamura T 《PloS one》2012,7(4):e34952
Background
We recently identified selenoprotein P (SeP) as a liver-derived secretory protein that causes insulin resistance in the liver and skeletal muscle; however, it is unknown whether and, if so, how SeP acts on adipose tissue. The present study tested the hypothesis that SeP is related to hypoadiponectinemia in patients with type 2 diabetes.Methodology/Principal Findings
We compared serum levels of SeP with those of adiponectin and other clinical parameters in 36 patients with type 2 diabetes. We also measured levels of blood adiponectin in SeP knockout mice. Circulating SeP levels were positively correlated with fasting plasma glucose (r = 0.35, P = 0.037) and negatively associated with both total and high-molecular adiponectin in patients with type 2 diabetes (r = −0.355, P = 0.034; r = −0.367, P = 0.028). SeP was a predictor of both total and high-molecular adiponectin, independently of age, body weight, and quantitative insulin sensitivity index (β = −0.343, P = 0.022; β = −0.357, P = 0.017). SeP knockout mice exhibited an increase in blood adiponectin levels when fed regular chow or a high sucrose, high fat diet.Conclusions/Significance
These results suggest that overproduction of liver-derived secretory protein SeP is connected with hypoadiponectinemia in patients with type 2 diabetes. 相似文献108.
Osamu Nakahara Masamichi Takahashi Hiroyuki Sase Toshiro Yamada Kazuhide Matsuda Tsuyoshi Ohizumi Haruo Fukuhara Takanobu Inoue Akiomi Takahashi Hiroyasu Kobayashi Ryusuke Hatano Tomoyuki Hakamata 《Biogeochemistry》2010,97(2-3):141-158
Rapid industrialization in East Asia is causing adverse effects due to atmospheric deposition in terrestrial and freshwater ecosystems. Decreasing stream pH and alkalinity and increasing NO3 ? concentrations were observed throughout the 1990s in the forested Lake Ijira catchment in central Japan. We investigated these changes using data on atmospheric deposition, soil chemistry, stream water chemistry, and forest growth. Average atmospheric depositions (wet + dry) of 0.83, 0.57, and 1.37 kmol ha?1 year?1 for hydrogen, sulfur, and nitrogen, respectively, were among the highest levels in Japan. Atmospheric deposition generally decreased before 1994 and increased thereafter. The catchment was acid-sensitive; stream alkalinity was low (134 μmolc l?1) and pH in surface mineral soils decreased from 4.5 in 1990 to 3.9 in 2003. Stream NO3 ? concentration nearly doubled (from 22 to 42 μmolc l?1) from the late 1980s to the early 2000s. Stream NO3 ? concentration was controlled primarily by water temperature before 1996/1997 and by stream discharge thereafter. Stream NO3 ? concentrations decreased during the growing season before 1996/1997, but this seasonality was lost thereafter. The catchment became nitrogen-saturated (changing from stage 1 to 2) in 1996/1997, possibly because of declining forest growth rates due to the 1994 summer drought, defoliation of Japanese red pine by pine wilt disease, maturation of Japanese cedar stands, and stimulation of nitrogen mineralization and nitrification due to alkalinization of soils (increased exchangeable Ca2+ and soil pH) after the summer drought. Stream pH and alkalinity began decreasing in 1996/1997. The enhanced growing-season NO3 ? discharge since 1996/1997 appeared to be the major cause of stream acidification. Increased atmospheric deposition since 1994 may have contributed to this change. 相似文献
109.
Masato Watanabe Kanji Uchida Kazuhide Nakagaki Bruce C. Trapnell Koh Nakata 《Cytokine & growth factor reviews》2010,21(4):263-273
Numerous reports have documented the presence of autoantibodies working against naturally occurring cytokines in humans in health and disease. In most instances, their physiological and pathophysiological significance remains unknown. However, recent advances in the methodologies for detecting cytokine autoantibodies and their application in research focused on specific disorders have shown that some cytokine autoantibodies play an important role in the pathogenesis of disease. Additionally, levels of cytokine autoantibodies may also correlate with disease severity and progression in certain infectious and autoimmune diseases but not in others. This suggests that cytokine-specific pathogenic differences exist. While multiple lines of evidence support the notion that high avidity cytokine autoantibodies are present and likely to be ubiquitous in healthy individuals, their potential physiological role, if any, is less clear. It is believed that they may function by scavenging pro-inflammatory cytokines and thereby inhibiting deleterious ‘endocrine’ effects, or by serving as carrier proteins, providing a ‘reservoir’ of inactive cytokines and thus modulating cytokine bioactivity. A central hypothesis is that sustained or repeated high-level exposure to cytokines triggers defects in T-cell tolerance, resulting in the expansion of existing cytokine autoantibody-producing B cells. 相似文献
110.