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481.
Correlation of Sprouty1 and Jagged1 With Aggressive Prostate Cancer Cells With Different Sensitivities to Androgen Deprivation
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482.
Sachiyo Nagi Evans A. Chadeka Toshihiko Sunahara Faith Mutungi Yombo K. Dan Justin Satoshi Kaneko Yoshio Ichinose Sohkichi Matsumoto Sammy M. Njenga Masahiro Hashizume Masaaki Shimada Shinjiro Hamano 《PLoS neglected tropical diseases》2014,8(7)
Background
An increasing risk of Schistosoma mansoni infection has been observed around Lake Victoria, western Kenya since the 1970s. Understanding local transmission dynamics of schistosomiasis is crucial in curtailing increased risk of infection.Methodology/Principal Findings
We carried out a cross sectional study on a population of 310 children from eight primary schools. Overall, a total of 238 (76.8%) children were infected with S. mansoni, while seven (2.3%) had S. haematobium. The prevalence of hookworm, Trichuris trichiura and Ascaris lumbricoides were 6.1%, 5.2% and 2.3%, respectively. Plasmodium falciparum was the only malaria parasite detected (12.0%). High local population density within a 1 km radius around houses was identified as a major independent risk factor of S. mansoni infection. A spatial cluster of high infection risk was detected around the Mbita causeway following adjustment for population density and other potential risk factors.Conclusions/Significance
Population density was shown to be a major factor fuelling schistosome infection while individual socio-economic factors appeared not to affect the infection risk. The high-risk cluster around the Mbita causeway may be explained by the construction of an artificial pathway that may cause increased numbers of S. mansoni host snails through obstruction of the waterway. This construction may have, therefore, a significant negative impact on the health of the local population, especially school-aged children who frequently come in contact with lake water. 相似文献483.
Masakazu Tomiyama Shin-ichiro Inoue Tomo Tsuzuki Midori Soda Sayuri Morimoto Yukiko Okigaki Takaya Ohishi Nobuyoshi Mochizuki Koji Takahashi Toshinori Kinoshita 《Journal of plant research》2014,127(4):553-563
To elucidate the molecular mechanisms of stomatal opening and closure, we performed a genetic screen using infrared thermography to isolate stomatal aperture mutants. We identified a mutant designated low temperature with open-stomata 1 (lost1), which exhibited reduced leaf temperature, wider stomatal aperture, and a pale green phenotype. Map-based analysis of the LOST1 locus revealed that the lost1 mutant resulted from a missense mutation in the Mg-chelatase I subunit 1 (CHLI1) gene, which encodes a subunit of the Mg-chelatase complex involved in chlorophyll synthesis. Transformation of the wild-type CHLI1 gene into lost1 complemented all lost1 phenotypes. Stomata in lost1 exhibited a partial ABA-insensitive phenotype similar to that of rtl1, a Mg-chelatase H subunit missense mutant. The Mg-protoporphyrin IX methyltransferase (CHLM) gene encodes a subsequent enzyme in the chlorophyll synthesis pathway. We examined stomatal movement in a CHLM knockdown mutant, chlm, and found that it also exhibited an ABA-insensitive phenotype. However, lost1 and chlm seedlings all showed normal expression of ABA-induced genes, such as RAB18 and RD29B, in response to ABA. These results suggest that the chlorophyll synthesis enzymes, Mg-chelatase complex and CHLM, specifically affect ABA signaling in the control of stomatal aperture and have no effect on ABA-induced gene expression. 相似文献
484.
Paulo De Marco Jr. Denis Silva Nogueira Caroline Costa Correa Thiago Bernardi Vieira Karina Dias Silva Nelson Silva Pinto David Bichsel Andrezza Sayuri Victoriano Hirota Raísa Romênia Silva Vieira Fernanda Melo Carneiro Arthur A. Bispo de Oliveira Priscilla Carvalho Rogério Pereira Bastos Christiane Ilg Beat Oertli 《Hydrobiologia》2014,723(1):87-101
There is a worldwide concern on the loss of pond biodiversity in human dominated landscapes. Nevertheless, agricultural activities appear to increase pond number in the Brazilian Cerrado through damming streams for cattle raising. These man-made ponds may represent important landscape features, but their importance to regional biodiversity has not yet been studied. Here, we evaluated differences in alpha and beta diversity under a multi-taxonomic approach, as well as tested pond size as the main driver of local species richness. We also assessed the importance of environmental heterogeneity through the analysis of the regional species accumulation curves (SAC). The overall result suggests that species turnover was the major component of regional biodiversity for all groups. Major physical and chemical water conditions had no effects on algae, macrophytes, water bugs, and birds species richness. Pond size had a significant effect on Odonata and fish species richness, while water beetles and amphibians were influenced by trophic conditions. Results from regional SAC show variations among different taxonomic groups regarding landscape heterogeneity: only algae, fish, and birds do not reached to an asymptote and had higher z-values. Our results highlight the importance of ponds for biodiversity conservation in increasingly agricultural landscapes in central Brazil. 相似文献
485.
486.
Sato T Otaka M Odashima M Kato S Jin M Konishi N Matsuhashi T Watanabe S 《Biochemical and biophysical research communications》2006,346(1):339-344
BACKGROUND AND AIMS: Type IV phosphodiesterase is a key enzyme to metabolize intracellular adenosine 3',5'-cyclic monophosphate (cAMP) expressed in inflammatory cells. The specific type IV phosphodiesterase inhibitor that increases intracellular cAMP is known to be potent suppressor of proinflammatory cytokines. However, the effect of phosphodiesterase inhibitors on the development of pancreatitis has not been well understood. In the present study, we examined the effect of a specific type IV phosphodiesterase inhibitor on experimentally induced pancreatitis. METHODS: Severity of cerulein-induced pancreatitis and pancreatic proinflammatory cytokine levels were studied with or without pretreatment with a specific type IV phosphodiesterase inhibitor (rolipram) in Sprague-Dawley rats. RESULTS: Administration of rolipram clearly ameliorated severity of pancreatitis evaluated by edema, serum amylase (P<0.05), and lipase levels (P<0.05) in rats. Also, the level of pancreatic proinflammatory cytokine (interleukin-1beta (IL-1beta)) was significantly reduced when rats were treated with rolipram prior cerulein injection (P<0.05). CONCLUSIONS: Our results demonstrated that intracellular cAMP and pancreatic proinflammatory cytokine level, which are regulated by type IV phosphodiesterase, might play an important role in the pathogenesis of acute pancreatitis. 相似文献
487.
488.
Yoshimura T Takeda A Hamano S Miyazaki Y Kinjyo I Ishibashi T Yoshimura A Yoshida H 《Journal of immunology (Baltimore, Md. : 1950)》2006,177(8):5377-5385
Recent lines of evidence have demonstrated that IL-27, a newly identified IL-12-related cytokine, has two apparently conflicting roles in immune responses: one as an initiator of Th1 responses and the other as an attenuator of inflammatory cytokine production. Although the IL-27-mediated Th1 initiation mechanism has been elucidated, little is known about the molecular basis for the suppression of cytokine production. In the present study, we demonstrated that IL-27 suppressed the production of various proinflammatory cytokines by fully activated CD4+ T cells while it had no effect on the cytokine production by CD4+ T cells at early phases of activation. IL-27 also suppressed IL-17 production by activated CD4+ T cells, thereby counteracting IL-23, another IL-12-related cytokine with proinflammatory effects. In fully activated CD4+ T cells, STAT3 was preferentially activated by IL-27 stimulation, whereas both STAT1 and 3 were activated by IL-27 in early activated CD4+ T cells. Lack of STAT3 in fully activated cells impaired the suppressive effects of IL-27. These data indicated that the preferential activation of STAT3 in fully activated CD4+ T cells plays an important role in the cytokine suppression by IL-27/WSX-1. 相似文献
489.
Hippocampal calcium dyshomeostasis and long-term potentiation in 2-week zinc deficiency 总被引:1,自引:2,他引:1
Takeda A Yamada K Tamano H Fuke S Kawamura M Oku N 《Neurochemistry international》2008,52(1-2):241-246
On the basis of abnormal neuropsychological behavior in the open-field test after 2-week zinc deprivation, neurochemical response was examined in young mice fed a zinc-deficient diet for 2 weeks. Serum corticosterone concentration was markedly higher in zinc-deficient mice than in the control mice. Basal signals of intracellular calcium (fluo-4 FF) were also significantly more in hippocampal slices from zinc-deficient mice. These results suggest that basal Ca2+ levels in hippocampal cells are increased by zinc deficiency. On the other hand, Schaffer collateral long-term potentiation (LTP) was unaffected by zinc deficiency; the averaged fEPSP after tetanic stimulation was 162+/-8% of baseline value in the control and 172+/-22% in zinc-deficient mice. In the Morris water maze, there was also no significant difference in learning behavior for the hidden platform task between the control and zinc-deficient mice. The present study indicates that Schaffer collateral LTP associated with spatial cognition performance are unaffected by calcium dyshomeostasis in the hippocampus elicited by 2-week zinc deprivation, which may be linked to the increased serum corticosterone concentration. 相似文献
490.
Shelterin promotes tethering of late replication origins to telomeres for replication‐timing control
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Shiho Ogawa Sayuri Kido Tetsuya Handa Hidesato Ogawa Haruhiko Asakawa Tatsuro S Takahashi Takuro Nakagawa Yasushi Hiraoka Hisao Masukata 《The EMBO journal》2018,37(15)
DNA replication initiates at many discrete loci on eukaryotic chromosomes, and individual replication origins are regulated under a spatiotemporal program. However, the underlying mechanisms of this regulation remain largely unknown. In the fission yeast Schizosaccharomyces pombe, the telomere‐binding protein Taz1, ortholog of human TRF1/TRF2, regulates a subset of late replication origins by binding to the telomere‐like sequence near the origins. Here, we showed using a lacO/LacI‐GFP system that Taz1‐dependent late origins were predominantly localized at the nuclear periphery throughout interphase, and were localized adjacent to the telomeres in the G1/S phase. The peripheral localization that depended on the nuclear membrane protein Bqt4 was not necessary for telomeric association and replication‐timing control of the replication origins. Interestingly, the shelterin components Rap1 and Poz1 were required for replication‐timing control and telomeric association of Taz1‐dependent late origins, and this requirement was bypassed by a minishelterin Tpz1‐Taz1 fusion protein. Our results suggest that Taz1 suppresses replication initiation through shelterin‐mediated telomeric association of the origins at the onset of S phase. 相似文献