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71.
Journal of Natural Medicines - A new crinine-type alkaloid crijaponine A (1), a new galanthamine-type alkaloid crijaponine B (2), and 11 known alkaloids—ungeremine (3), lycorine (4),...  相似文献   
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Helicobacter cinaedi infection is recognized as an increasingly important emerging disease in humans. Although H. cinaedi-like strains have been isolated from a variety of animals, it is difficult to identify particular isolates due to their unusual phenotypic profiles and the limited number of biochemical tests for detecting helicobacters. Moreover, analyses of the 16S rRNA gene sequences are also limited due to the high levels of similarity among closely related helicobacters. This study was conducted to evaluate intact-cell mass spectrometry (ICMS) profiling using matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS) as a tool for the identification of H. cinaedi. A total of 68 strains of H. cinaedi isolated from humans, dogs, a cat, and hamsters were examined in addition to other Helicobacter species. The major ICMS profiles of H. cinaedi were identical and differed from those of Helicobacter bilis, which show >98% sequence similarity at the 16S rRNA sequence level. A phyloproteomic analysis of the H. cinaedi strains examined in this work revealed that human isolates formed a single cluster that was distinct from that of the animal isolates, with the exception of two strains from dogs. These phyloproteomic results agreed with those of the phylogenetic analysis based on the nucleotide sequences of the hsp60 gene. Because they formed a distinct cluster in both analyses, our data suggest that animal strains may not be a major source of infection in humans. In conclusion, the ICMS profiles obtained using a MALDI-TOF MS approach may be useful for the identification and subtyping of H. cinaedi.  相似文献   
74.
The opportunity to undergo an induced pluripotent stem cell-based autologous transplant can strike patients as a chance for a cure from a debilitating condition with few options for respite. However, when clinical studies of this caliber present themselves, patients and researchers, each with their own set of motives, may find it difficult to take a balanced approach to evaluating them. We present a patient-centered risk-benefit analysis of the iPSC-based clinical research currently underway in Japan, including a survey of in vitro and in vivo tests that support this project, an in-depth discussion of risks, and further elucidation of considerations patients may wish to consider. The arguments presented will assist patients in undertaking a more informed decision-making process.  相似文献   
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Vascular calcification progresses under hyperphosphatemia, and represents a risk factor for cardiovascular disease in chronic kidney disease (CKD) patients. We recently indicated that phosphorus (P) fluctuations also exacerbated vascular calcification in early-stage CKD rats. Dietary fiber intake is reportedly associated with cardiovascular risk. This study investigated the effects of dietary fiber on vascular calcification by repeated P fluctuations in early-stage CKD rats. Unilateral nephrectomy rats were used as an early-stage CKD model. For 36 days, a P fluctuation (LH) group was fed low-P (0.02% P) and high-P (1.2% P) diets alternating every 2 days, and a P fluctuation with dietary fiber intake (LH + F) group was fed low-P and high-P diets containing dietary fiber alternating every 2 days. The effect on vascular calcification was measured calcium content. Effects on uremic toxin were measured levels of indoxyl sulfate (IS) and investigated gut microbiota. The LH + F group showed significantly reduced vessel calcium content compared to the LH group. Further, dietary fiber inhibited increases in blood levels of IS after intake of high-P diet, and decreased uremic toxin-producing intestinal bacteria. Dietary fiber may help suppress progression of vascular calcification due to repeated P fluctuations in early-stage CKD rats by decreasing uremic toxin-producing intestinal bacteria.  相似文献   
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Human breast-cancer specimens from 100 patients were analyzed for microsatellite instability (referred to as replication error; RER) at 12 genomic loci on 7 chromosomes, and results were correlated with clinicopathologic characteristics. In 42 of 100 breast-cancer patients, we investigated whether RER was associated with the amplification of oncogenes and/or suppression of tumor-suppressor genes. Of the 100 patients, 8 (8%) were RER-positive at one or more chromosomal loci. The majority of RER-positive patients had early-stage disease with ER-positive tumors, suggesting that RER occurs early in breast tumorigenesis. However, no significant correlation was observed between RER and oncogenes or tumor-suppressor genes. Thus, the mechanism of RER in sporadic human breast cancer may be independent of the multi-step carcinogenesis caused by the alterations of oncogenes and tumor-suppressor genes. © 1996 Wiley-Liss, Inc.  相似文献   
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Uremic sarcopenia is a serious clinical problem associated with physical disability and increased morbidity and mortality. Methylglyoxal (MG) is a highly reactive, dicarbonyl uremic toxin that accumulates in the circulatory system in patients with chronic kidney disease (CKD) and is related to the pathology of uremic sarcopenia. The pathophysiology of uremic sarcopenia is multifactorial; however, the details remain unknown. We investigated the mechanisms of MG-induced muscle atrophy using mouse myoblast C2C12 cells, focusing on intracellular metabolism and mitochondrial injury. We found that one of the causative pathological mechanisms of uremic sarcopenia is metabolic flow change to fatty acid synthesis with MG-induced ATP shortage in myoblasts. Evaluation of cell viability revealed that MG showed toxic effects only in myoblast cells, but not in myotube cells. Expression of mRNA or protein analysis revealed that MG induces muscle atrophy, inflammation, fibrosis, and oxidative stress in myoblast cells. Target metabolomics revealed that MG induces metabolic alterations, such as a reduction in tricarboxylic acid cycle metabolites. In addition, MG induces mitochondrial morphological abnormalities in myoblasts. These changes resulted in the reduction of ATP derived from the mitochondria of myoblast cells. Our results indicate that MG is a pathogenic factor in sarcopenia in CKD.  相似文献   
80.
Amenamevir is a potent helicase–primase inhibitor and a novel class of antiviral agent other than nucleoside compounds, such as aciclovir, valaciclovir and famciclovir. This study is the first randomized, double‐blind, valaciclovir‐controlled phase 3 study to evaluate the efficacy and safety of amenamevir in Japanese patients with herpes zoster when treated within 72 h after onset of rash. A total of 751 patients were randomly assigned to receive either amenamevir 400 mg or 200 mg p.o. once daily or valaciclovir 1000 mg three times daily (daily dose, 3000 mg) for 7 days. The primary efficacy end‐point was the proportion of cessation of new lesion formation by day 4 (“day 4 cessation proportion”). The day 4 cessation proportions for amenamevir 400 and 200 mg and valaciclovir were 81.1% (197/243), 69.6% (172/247) and 75.1% (184/245), respectively. Non‐inferiority of amenamevir 400 mg to valaciclovir was confirmed by a closed testing procedure. Days to cessation of new lesion formation, complete crusting, healing, pain resolution and virus disappearance were evaluated as secondary end‐points. No significant differences were observed in any of the treatment groups. Amenamevir 400 and 200 mg were well tolerated as well as valaciclovir. The proportions of patients who experienced drug‐related adverse events were 10.0% (25/249), 10.7% (27/252) and 12.0% (30/249) with amenamevir 400 and 200 mg and valaciclovir, respectively. In conclusion, amenamevir 400 mg appears to be effective and well tolerated for treatment of herpes zoster in immunocompetent Japanese patients.  相似文献   
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