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41.
C-3 esterifications of betulinic acid (BA, 1) and its A-ring homolog, ceanothic acid (CA, 2), were carried out to provide sixteen terpenoids, 419, including nine new compounds (412). All synthesized compounds were evaluated in an in vitro antitumor-promoting assay using the Epstein-Barr virus early antigen (EBV-EA) activation induced by 12-O-tetradecanoylphorbol-13-acetate (TPA) in Raji cells. Among them, compounds 46, 1114, 16, and 17 displayed remarkable inhibitory effects of EBV-EA activation. BA analog 6, which contains a prenyl-like group, showed the most potent inhibitory effect (100%, 76%, 37%, and 11% inhibition of EBA activation at 1000, 500, 100, and 10 mol ratio/TPA, respectively, with IC50 value of 285 mol ratio/32 pmol TPA). Compound 6 merits further development as a cancer preventive agent.  相似文献   
42.
Pandanus boninensis, endemic to the Ogasawara Islands, Japan, is distributed on both the older Bonin and younger Volcano Islands. In this study, we conducted population genetic analyses of P. boninensis on these islands to examine the population diversity and structure across old and young islands, to assess potential differences in population demography with island age, and to collect any evidence of migration between old and young islands. We found that the genetic diversity of expressed sequence tag (EST)–based microsatellite (SSR) markers, the nucleotide diversity of nuclear DNA sequences, and the haplotype diversity of chloroplast DNA on young islands were lower than those on old islands. Clustering analyses of EST‐SSR indicated that populations on old islands were strongly diverged from those on young islands. Approximate Bayesian computation analysis of EST‐SSR suggested that population expansion occurred on old islands while population reduction occurred on young islands. We also found evidence of migration among old islands (mostly from south to north), while it appears that there have been very few migration events between old and young islands. These differences could be due to the fact that young islands tend to be geographically isolated and support smaller populations that began a shorter time ago from limited founders. The P. boninensis populations on the Volcano Islands are interesting from an evolutionary perspective as they constitute a classic example of the early stages of progressive colonization on oceanic islands with small effective population sizes and low genetic diversity.  相似文献   
43.
At the Nakabusa hot spring, Japan, dense olive-green microbial mats develop in regions where the slightly alkaline, sulfidic effluent has cooled to 65 °C. The microbial community of such mats was analyzed by focusing on the diversity, as well as the in situ distribution and function of bacteria involved in sulfur cycling. Analyses of 16S rRNA and functional genes (aprA, pufM) suggested the importance of three thermophilic bacterial groups: aerobic chemolithotrophic sulfide-oxidizing species of the genus Sulfurihydrogenibium (Aquificae), anaerobic sulfate-reducing species of the genera Thermodesulfobacterium/Thermodesulfatator, and filamentous anoxygenic photosynthetic species of the genus Chloroflexus. A new oligonucleotide probe specific for Sulfurihydrogenibium was designed and optimized for catalyzed reporter deposition fluorescence in situ hybridization (CARD-FISH). In situ hybridizations of thin mat sections showed a heterogeneous vertical distribution of Sulfurihydrogenibium and Chloroflexus. Sulfurihydrogenibium dominated near the mat surface (50% of the total mat biovolume), while Chloroflexus dominated in deeper layers (up to 64% of the total mat biovolume). Physiological experiments monitoring in vitro changes of sulfide concentration indicated slight sulfide production by sulfate-reducing bacteria under anoxic-dark conditions, sulfide consumption by photosynthetic bacteria under anoxic-light conditions and strong sulfide oxidation by chemolithotrophic members of Aquificae under oxic-dark condition. We therefore propose that Sulfurihydrogenibium spp. act as highly efficient scavengers of oxygen from the spring water, thus creating a favorable, anoxic environment for Chloroflexus and Thermodesulfobacterium/Thermodesulfatator in deeper layers.  相似文献   
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Primary neuroendocrine neoplasm of the liver is extremely rare in both humans and non‐human primates. The present report describes the clinical and pathological findings of an aged Japanese macaque (Macaca fuscata) with hepatic neuroendocrine carcinoma. To our knowledge, this is the first report of hepatic neuroendocrine neoplasm in macaques.  相似文献   
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The skin is an immune organ that contains innate and acquired immune systems and thus is able to respond to exogenous stimuli producing large amount of proinflammatory cytokines including IL-1 and IL-1 family members. The role of the epidermal IL-1 is not limited to initiation of local inflammatory responses, but also to induction of systemic inflammation. However, association of persistent release of IL-1 family members from severe skin inflammatory diseases such as psoriasis, epidermolysis bullosa, atopic dermatitis, blistering diseases and desmoglein-1 deficiency syndrome with diseases in systemic organs have not been so far assessed. Here, we showed the occurrence of severe systemic cardiovascular diseases and metabolic abnormalities including aberrant vascular wall remodeling with aortic stenosis, cardiomegaly, impaired limb and tail circulation, fatty tissue loss and systemic amyloid deposition in multiple organs with liver and kidney dysfunction in mouse models with severe dermatitis caused by persistent release of IL-1s from the skin. These morbid conditions were ameliorated by simultaneous administration of anti-IL-1α and IL-1β antibodies. These findings may explain the morbid association of arteriosclerosis, heart involvement, amyloidosis and cachexia in severe systemic skin diseases and systemic autoinflammatory diseases, and support the value of anti-IL-1 therapy for systemic inflammatory diseases.  相似文献   
49.
Canine distemper virus (CDV) vaccination confers long-term protection against CDV reinfection. To investigate the utility of CDV as a polyvalent vaccine vector for Leishmania, we generated recombinant CDVs, based on an avirulent Yanaka strain, that expressed Leishmania antigens: LACK, TSA, or LmSTI1 (rCDV–LACK, rCDV–TSA, and rCDV–LmSTI1, respectively). Dogs immunized with rCDV-LACK were protected against challenge with lethal doses of virulent CDV, in the same way as the parental Yanaka strain. To evaluate the protective effects of the recombinant CDVs against cutaneous leishmaniasis in dogs, dogs were immunized with one recombinant CDV or a cocktail of three recombinant CDVs, before intradermal challenge (in the ears) with infective-stage promastigotes of Leishmania major. Unvaccinated dogs showed increased nodules with ulcer formation after 3 weeks, whereas dogs immunized with rCDV–LACK showed markedly smaller nodules without ulceration. Although the rCDV–TSA- and rCDV–LmSTI1-immunized dogs showed little protection against L. major, the cocktail of three recombinant CDVs more effectively suppressed the progression of nodule formation than immunization with rCDV–LACK alone. These results indicate that recombinant CDV is suitable for use as a polyvalent live attenuated vaccine for protection against both CDV and L. major infections in dogs.  相似文献   
50.

Purpose

To assess the prevalence of glaucoma in patients with high myopia defined as myopic refractive error of >-8 diopters or axial length ≥26.5 mm.

Methods

The hospital-based observational study included 172 patients (336 eyes) with a mean age of 61.9±12.3 years and mean axial length of 30.1±2.3 mm (range: 24.7–39.1mm). Glaucomatous-type optic discs were defined by glaucomatous optic disc appearance. Glaucoma was defined by glaucomatous optic disc appearance and glaucomatous Goldmann visual field defects not corresponding with myopic macular changes.

Results

Larger disc area (mean: 3.18±1.94 mm2) was associated with longer axial length (P<0.001; standardized correlation coefficient: 0.45). Glaucoma was detected in 94 (28%; 95% Confidence intervals: 23%, 33%) eyes. In multivariate analysis, glaucoma prevalence was 3.2 times higher (P<0.001) in megalodiscs (>3.79 mm2) than in normal-sized discs or small discs (<1.51 mm2) after adjusting for older age. Axial length was not significantly (P = 0.38) associated with glaucoma prevalence in that model. Glaucoma prevalence increased by a factor of 1.39 for each increase in optic disc area by one mm2. Again, axial length was not significantly (P = 0.38) associated with glaucoma prevalence when added to this multivariate model.

Conclusion

Within highly myopic individuals, glaucoma prevalence increased with larger optic disc size beyond a disc area of 3.8 mm2. Highly myopic megalodiscs as compared to normal sized discs or small discs had a 3.2 times higher risk for glaucomatous optic nerve neuropathy. The increased glaucoma prevalence in axial high myopia was primarily associated with axial myopia associated disc enlargement and not with axial elongation itself.  相似文献   
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