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401.
Osamu Nunobiki Daisuke Sano Kyoko Akashi Taro Higashida Toshitada Ogasawara Hikari Akise Shinji Izuma Kiyo Torii Yoshiaki Okamoto Ichiro Tanaka Masatsugu Ueda 《Human cell》2016,29(2):91-95
To investigate the clinical significance of ALDH2 genetic polymorphisms in cervical carcinogenesis. ALDH2 polymorphisms together with human papillomavirus (HPV) types were examined in a total of 195 cervical smear in exfoliated cervical cell samples using Real-Time polymerase chain reaction (PCR) System. The frequency for the AG+AA genotype was seven in the normal group (70.0 %), 16 in the LSIL group (57.1 %), and 27 in the HSIL group (90.0 %). A significant difference was found between the LSIL and HSIL groups (P = 0.0064). Patients with HSIL lesions frequently had high-risk HPV infections and concurrently belonged to the AG+AA group. ALDH2 genotype in cervical cell samples may be associated with more severe precancerous lesions of the cervix in a Japanese population. 相似文献
402.
Brigitte L. Melly Denise M. Schael Nick Rivers-Moore Phumelele T. Gama 《Wetlands Ecology and Management》2017,25(3):313-330
Until recently, little research has been conducted on the distribution and structure of ephemeral systems in semi-arid areas. This information is critical for appropriate wetland management and conservation. The Nelson Mandela Bay Municipality is a semi-arid area along the south-eastern coastline of the Eastern Cape Province of South Africa. The Municipality encapsulates a wide range of geological and geomorphological features as well as vegetation types within an area of some 1950 km2, providing an ideal area for such research. The distribution and abundance of wetlands were defined, and a logistic regression (LR) model was used to establish whether this modelling technique is viable in semi-arid areas with highly variable rainfall patterns. Wetlands were delineated manually using geographical information systems, high-resolution aerial photographs and environmental data. More than 1700 wetland polygons were identified, with 80% of the systems being categorised as depressions, seeps and wetland flats. Unchannelled (8%) and channelled (7%) valley bottom wetlands and floodplain wetlands (5%) were also identified. The wetland database was then used to create a wetland occurrence probability model. There were 19 environmental variables used to develop the LR model, with eight variables used in the final model output. The predictive capacity of the model was good, with an area under curve value of 0.68 and an overall accuracy of 66%. This indicates that probabilistic wetland models are useful in highly variable environments with high numbers of small (<1 ha) wetlands. Such predictive models provide a tool to assist in improving the accuracy of land cover datasets in semi-arid areas, and can be used to inform management decisions on flood risk areas and key conservation zones. In addition, abiotic variables that are significant in the model output provide an indication of the factors influencing wetland functioning in the region. 相似文献
403.
Qingzhi Wang Fengjuan Jiao Pei Zhang Jianguo Yan Zheng Zhang Feng He Qian Zhang Zexi Lv Xiang Peng Hongwei Cai Bo Tian 《Molecular neurobiology》2018,55(5):3709-3717
The molecular mechanisms responsible for the loss of dopaminergic neurons in Parkinson’s disease (PD) remain obscure. Loss of function of E3 ubiquitin ligases is associated with mitochondria dysfunction, dysfunction of protein degradation, and α-synuclein aggregation, which are major contributors to neurodegeneration in PD. Recent research has thus focused on E3 ubiquitin ligase glycoprotein 78 (GP78); however, the role of GP78 in PD pathogenesis remains unclear. Notably, cyclin-dependent kinase 5 (CDK5) controls multiple cellular events in postmitotic neurons, and CDK5 activity has been implicated in the pathogenesis of PD. Thus, we addressed the relationship between CDK5 and GP78 in MPTP-based PD models. We found that GP78 expression is decreased in MPTP-based cellular and animal PD models, and CDK5 directly phosphorylated GP78 at Ser516, which promoted the ubiquitination and degradation of GP78. Importantly, overexpression of GP78 or interference of GP78 Ser516 phosphorylation protected neurons against MPP+-induced cell death. Thus, our research reveals that the CDK5-GP78 pathway is involved in the pathogenesis of PD and could be a novel candidate drug target for the treatment of PD. 相似文献
404.
Microbial decolorization of spentwash: a review 总被引:1,自引:0,他引:1
Spentwash is one of the most complex and cumbersome wastewater with very high BOD, COD and other organic and inorganic toxic
constituents. It is dark brown colored and difficult to treat by normal biological process such as activated sludge or anaerobic
lagooning. The color is due to the presence of melanoidins, caramels and other polymers. These compounds have anti oxidant
properties which render them toxic to microorganisms. Spentwash disposal into the environment is hazardous and has a considerable
pollution potential. It affects the aesthetic merit. Its decolorization by physical or chemical methods have been investigated
and were found unsuitable. In the recent past, increasing attention has been directed towards utilizing microbial activity
for decolorization of spentwash. This review reveals various groups of microorganisms which have potential in spentwash decolorization.
The role of enzymes in decolorization and the microbial degradation of individual compounds imparting color to spentwash are
also discussed. 相似文献
405.
Eduard Akhunov Charles Nicolet Jan Dvorak 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2009,119(3):507-517
Single nucleotide polymorphisms (SNPs) are indispensable in such applications as association mapping and construction of high-density
genetic maps. These applications usually require genotyping of thousands of SNPs in a large number of individuals. Although
a number of SNP genotyping assays are available, most of them are designed for SNP genotyping in diploid individuals. Here,
we demonstrate that the Illumina GoldenGate assay could be used for SNP genotyping of homozygous tetraploid and hexaploid
wheat lines. Genotyping reactions could be carried out directly on genomic DNA without the necessity of preliminary PCR amplification.
A total of 53 tetraploid and 38 hexaploid homozygous wheat lines were genotyped at 96 SNP loci. The genotyping error rate
estimated after removal of low-quality data was 0 and 1% for tetraploid and hexaploid wheat, respectively. Developed SNP genotyping
assays were shown to be useful for genotyping wheat cultivars. This study demonstrated that the GoldenGate assay is a very
efficient tool for high-throughput genotyping of polyploid wheat, opening new possibilities for the analysis of genetic variation
in wheat and dissection of genetic basis of complex traits using association mapping approach.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
406.
Analysis of trehalose-6-phosphate synthase (TPS) gene family suggests the formation of TPS complexes in rice 总被引:2,自引:0,他引:2
Trehalose-6-phosphate (T6P), an intermediate in the trehalose biosynthesis pathway, is emerging as an important regulator
of plant metabolism and development. T6P levels are potentially modulated by a group of trehalose-6-phosphate synthase (TPS)
and trehalose-6-phosphate phosphatase (TPP) homologues. In this study, we have isolated 11 TPS genes encoding proteins with both TPS and TPP domains, from rice. Functional complement assays performed in yeast tps1 and tps2 mutants, revealed that only OsTPS1 encodes an active TPS enzyme and no OsTPS protein possesses TPP activity. By using a yeast two-hybrid analysis, a complicated
interaction network occurred among OsTPS proteins, and the TPS domain might be essential for this interaction to occur. The
interaction between OsTPS1 and OsTPS8 in vivo was confirmed by bimolecular fluorescence complementation and coimmunoprecipitation
assays. Furthermore, our gel filtration assay showed that there may exist two forms of OsTPS1 (OsTPS1a and OsTPS1b) with different
elution profiles in rice. OsTPS1b was particularly cofractionated with OsTPS5 and OsTPS8 in the 360 kDa complex, while OsTPS1a
was predominantly incorporated into the complexes larger than 360 kDa. Collectively, these results suggest that OsTPS family members may form trehalose-6-phosphate synthase complexes and therefore potentially modify T6P levels to regulate
plant development. 相似文献
407.
Mutsumi Nakamura Takafumi Nagamine Chisato Harada Kiyoshi Tajima Hiroki Matsui Yoshimi Benno 《Current microbiology》2003,47(1):0071-0074
The objective of this study was to ligate the xylanase gene A (xynA) isolated from Ruminococcus albus 7 into the promoter and signal-peptide region of the lichenase [β-(1,3-1,4)-glucanase] gene of Streptococcus bovis JB1. This fusion gene was inserted into the pSBE11 vector, and the resulting recombinant, plasmid pXA, was used to transform
S. bovis 12-U-1 cells. The transformant, S. bovis 12UXA, secreted the xylanase, which was stable against freeze-thaw treatment and long-time incubation at 37°C. The introduction
of pXA and production of xylanase did not affect cell growth, and the xylanase produced degraded xylan from oat-spelt and
birchwood.
Received: 24 June 2002 / Accepted: 7 October 2002 相似文献
408.
The longnose filefish,Oxymonacanthus longirostris, usually lives in heterosexual pairs, the male and female swimming together and sharing the same territory. Pair territoriality
in the species was examined in detail in relation to sexual differences in territorial defense activities. Rigorous pair territoriality
was maintained only during the breeding season, although pairs used their home ranges exclusively to a certain extent, during
the non-breeding season. The frequency of aggression against other conspecific pairs in the breeding season was higher than
in the non-breeding season. Agonistic interactions appear to be over both mates and food resources, the strict pair territoriality
in the breeding season possibly being due to mutual mate guarding. In intraspecific aggressive interactions, males usually
led their partner females when attacking intruders. The feeding frequency of males was much lower than that of females in
the breeding season. Mate removal experiments indicated that females could not defend their original territories solitarily
and their feeding frequency decreased. Conversely, males could defend territories solitarily without a decrease in feeding
frequency. These results suggest that males contribute most to the defense of the pair territory, with females benefiting
from territorial pair-swimming with their partner males. 相似文献
409.
Miyamoto K Okunishi M Nukui E Tsuchiya T Kobayashi T Imada C Tsujibo H 《Archives of microbiology》2007,188(6):619-628
410.
Dennis Trolle Guangwei Zhu David Hamilton Liancong Luo Chris McBride Lu Zhang 《Hydrobiologia》2009,627(1):31-44
Distinct horizontal water column concentration gradients of nutrients and chlorophyll a (Chl a) occur within large, shallow, eutrophic Lake Taihu, China. Concentrations are high in the north, where some of the major
polluted tributaries enter the lake, and relatively low in the south, where macrophytes generally are abundant. It is not
clear, however, whether these water column concentration gradients are similarly reflected in spatial heterogeneity of nutrient
concentrations within the bottom sediments. The main objective of this study was therefore to test if horizontal and vertical
variations in the phosphorus and nitrogen content in bottom sediments of Lake Taihu are significantly related to (1) horizontal
variations in overlying water column nutrient concentrations and (2) other sediment geochemical constituents. We measured
the concentration of total phosphorus (TP) and total nitrogen (TN) in surficial sediments (0–2 cm) and TP, TN and Chl a concentrations in water column samples, collected from 32 sites in 2005. In 2006 sediment, TP, TN, carbon, iron and manganese
concentrations were measured vertically at 2 cm intervals, extending to a depth of approximately 20 cm, at an additional eight
sites. Linear correlation analysis revealed that surficial sediment TP concentrations across the 32 stations were related
significantly, though weakly, to annual mean water column concentrations of TP, TN as well as Chl a. Correlations of surficial sediment TN with water column variables were, however, not significant (P > 0.05). Amongst the geochemical variables tested, the vertical variability of sediment TP concentrations was most strongly
related to sediment manganese and carbon concentrations. A multiple stepwise linear regression revealed that the combination
of sediment manganese and carbon concentrations explained 91% of the horizontal variability in sediment TP concentrations
and 65% of the vertical variability.
Handling editor: Luigi Naselli-Flores 相似文献