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971.
Long-term data on surface water temperature (SWT) from 9 lakes larger than 10 km2 located in different climatic regions in Austria were analysed for June–September 1965–2009. The lakes are situated north and south of the Alps, in the east bordering Hungary and in the west bordering Germany. Time series of air temperature (AT) and SWT were smoothed by the lowess function and linear trends. Water temperature for the year 2050 was estimated from (1) linear extrapolation of the time trend, (2) projection of the AT–SWT relation and (3) increase of average present day SWT (2000–2009) by 3°C in summer in the Alps as expected from models by climatologists. Results indicate a rise in SWT parallel to AT since the mid-1960s. On an annual basis, changes in water temperature were the greatest in spring and summer. A conservative estimate of the average increase of summer SWT until 2050 is 2°C (1.2–2.9°C), differentiated by region. As a consequence of warming water temperatures, the duration of thermal stratification will increase and mixing and retention time will be affected. Changes in the food web are difficult to forecast, but will strongly depend on local environmental conditions and will therefore be different for individual lakes. 相似文献
972.
Hirokazu Ishii Takuma Shirai Chisato Makino Takahito Nishikata 《Development, growth & differentiation》2014,56(2):175-188
In ascidian eggs, cytoplasmic and cortical reorganization, previously called ooplasmic segregation, occurs in two phases during the first cell cycle. In the second phase of reorganization, the mitochondria‐rich cytoplasm (myoplasm) moves to the future posterior side, concurrent with sperm aster migration along the egg cortex. Although this reorganization is the critical step for establishing the anteroposterior axis, its molecular mechanism is not fully understood. In this study, we showed that low concentrations of the mitochondrial inhibitor sodium azide (NaN3), which showed the low toxicity in sperm, inhibited the second phase of reorganization without the microtubule depolymerization. In the NaN3‐treated embryo, the sperm aster was not attracted to the cortex and altered its migration pathway; therefore, the myoplasm remained at the vegetal pole. Consequently, the anteroposterior axis was not established. Another mitochondrial inhibitor, oligomycin, did not affect these processes. These results suggest that NaN3 inhibits unknown molecules that are important for the second phase of reorganization. Identifying the target molecule of NaN3 will lead to a molecular understanding of cytoplasmic and cortical reorganization. 相似文献
973.
Chiral alcohols are valuable as diverse chemicals and synthetic intermediate materials. Phenylacetaldehyde reductase (PAR) is an enzyme that converts a wide variety of ketones into chiral alcohols with high optical purity. When an alcohol such as 2-propanol is used as a hydrogen donor, PAR itself will also mediate the regeneration of the coenzyme NADH in situ. Perceiving a capacity for improvement, we sought to develop a PAR that is able to convert higher concentrations of substrates in the presence of high concentrations of 2-propanol. The selection procedure for mutants was re-examined and a procedure able to select an effective amino acid substitution was established. Two advantageous amino acid substitutions were successfully selected using the procedure. When high-concentration substrate conversion reaction was subjected with a mutant that integrated both the two amino acid substitutions, near-complete conversions of m-chlorophenacyl chloride (m-CPC) (2.1 mmol/ml) and ethyl 4-chloro-3-oxobutanoate (ECOB) (1.9 mmol/ml) were achieved. 相似文献
974.
Masayuki Sakiyama Hirotaka Matsuo Seiko Shimizu Toshinori Chiba Akiyoshi Nakayama Yuzo Takada Takahiro Nakamura Tappei Takada Emi Morita Mariko Naito Kenji Wakai Hiroki Inoue Seishiro Tatsukawa Junki Sato Kazumi Shimono Toshiaki Makino Takahiro Satoh Hiroshi Suzuki Yoshikatsu Kanai Nobuyuki Hamajima Yutaka Sakurai Kimiyoshi Ichida Toru Shimizu Nariyoshi Shinomiya 《Human cell》2014,27(1):1-4
Gout is a common disease resulting from hyperuricemia which causes acute arthritis. Recently, genome-wide association studies revealed an association between serum uric acid levels and a common variant of leucine-rich repeat-containing 16A (LRRC16A) gene. However, it remains to be clarified whether LRRC16A contributes to the susceptibility to gout. In this study, we investigated the relationship between rs742132 in LRRC16A and gout. A total of 545 Japanese male gout cases and 1,115 male individuals as a control group were genotyped. rs742132 A/A genotype significantly increased the risk of gout, conferring an odds ratio of 1.30 (95 % CI 1.05–1.60; p = 0.015). LRRC16A encodes a protein called capping protein ARP2/3 and myosin-I linker (CARMIL), which serves as an inhibitor of the actin capping protein (CP). CP is an essential element of the actin cytoskeleton, which binds to the barbed end of the actin filament and regulates its polymerization. In the apical membrane of proximal tubular cells in the human kidney, the urate-transporting multimolecular complex (urate transportsome) is proposed to consist of several urate transporters and scaffolding proteins, which interact with the actin cytoskeleton. Thus, if there is a CARMIL dysfunction and regulatory disability in actin polymerization, urate transportsome may be unable to operate appropriately. We have shown for the first time that CARMIL/LRRC16A was associated with gout, which could be due to urate transportsome failure. 相似文献
975.
976.
Y. Hayashi T. Saito T. Ohshima Y. Nakagawa T. Arita A. Yashima T. Makino R. Konnai K. Gomi T. Arai N. Maeda 《Archives of microbiology》2014,196(7):489-496
Previous studies of oral microbiota by culture-dependent or targeted DNA approaches demonstrated that hyposalivation, a reduction in salivary secretions, might increase the amount of certain oral pathogens. However, the relationship between hyposalivation and the balance of oral microbiota, especially uncultivable bacteria, remains still unclear. The aim of this study was to elucidate the relationship between hyposalivation and oral microbiota by analyzing terminal restriction fragment length polymorphism (T-RFLP) of 16S rDNA. The 61 subjects were divided into two groups, hyposalivation group and normo-salivation group. The microbiota of tongue-coating samples was analyzed by T-RFLP. The amount of saliva, the number of Candida albicans, and also the dental status including plaque index, gingival index, bleeding on probing, probing pocket depth and decayed, missing, and filled teeth (DMFT) were assessed. Regarding the dental status, none of the evaluated factors were significantly different between the groups except the number of DMFT. According to the T-RFLP profiles, the patterns of microbiota in the tongue coating were classified into two groups, Clusters I and II. Cluster I is made up 76 % of subjects with hyposalivation, while Cluster II is made up 61 % of subjects with normo-salivation (p < 0.001). Compared with the microbiota found in Cluster II, that in Cluster I had higher proportions of T-RFs corresponding to genera Veillonella, Dialister, Prevotella, Fusobacterium, and Streptococcus. T-RFLP analysis showed a significant role of salivary volume in determining the composition of the microbial community, regardless of the cultivability of the bacteria. 相似文献
977.
978.
Setsuko Komatsu Abu Hena Mostafa Kamal Takahiro Makino Zahed Hossain 《Biochimica et Biophysica Acta - Proteins and Proteomics》2014,1844(7):1208-1218
Biophotons are ultraweak photon emissions that are closely related to various biological activities and processes. In mammals, biophoton emissions originate from oxidative bursts in immunocytes during immunological responses. Biophotons emitted from plant organs provide novel information about the physiological state of plant under in vivo condition. In this review, the principles and recent advances in the measurement of biophoton emissions in plants are described. Furthermore, examples of biophoton emission and proteomics in soybean under abiotic stress are reviewed and discussed. Finally, this review suggests that the application of proteomics should provide a better interpretation of plant response to biophoton emission and allow the identification of genes that will allow the screening of crops able to produce maximal yields, even in stressful environments. 相似文献
979.
980.
Daniel Wong Wanseon Lee Peter Humburg Seiko Makino Evelyn Lau Vivek Naranbhai Benjamin P Fairfax Kenneth Chan Katharine Plant Julian C Knight 《Genome biology》2014,15(10)