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91.
The ATP-binding cassette, subfamily G, member 2 gene ABCG2/BCRP locates in a gout-susceptibility locus (MIM 138900) on chromosome 4q. Recent genome-wide association studies also showed that the ABCG2 gene relates to serum uric acid levels and gout. Since ABCG2 is also known as a transporter of nucleotide analogs that are structurally similar to urate, and is an exporter that has common polymorphic reduced functionality variants, ABCG2 could be a urate secretion transporter and a gene causing gout. To find candidate mutations in ABCG2, we performed a mutation analysis of the ABCG2 gene in 90 Japanese patients with hyperuricemia and found six non-synonymous mutations. Among the variants, ATP-dependent urate transport was reduced or eliminated in five variants, and two out of the five variants (Q126X and Q141K) were frequently detected in patients. Haplotype frequency analysis revealed that there is no simultaneous presence of Q126X and Q141K in one haplotype. As Q126X and Q141K are a nonfunctional and half-functional haplotype, respectively, their genotype combinations are divided into four estimated functional groups. The association study with 161 male gout patients and 865 male controls showed that all of those who had dysfunctional ABCG2 had an increased risk of gout, and that a remarkable risk was observed in those with ≤1/4 function (OR, 25.8; 95% CI, 10.3–64.6; p = 3.39 × 10?21). In 2,150 Japanese individuals, the frequency of those with dysfunctional ABCG2 was more than 50%. Our function-based clinicogenetic analysis identified the combinations of dysfunctional variants of ABCG2 as a major contributing factor in Japanese patients with gout.  相似文献   
92.
Recent genome-wide association studies showed that serum uric acid (SUA) levels relate to ABCG2/BCRP gene, which locates in a gout-susceptibility locus revealed by a genome-wide linkage study. Together with the ABCG2 characteristics, we hypothesized that ABCG2 transports urate and its dysfunction causes hyperuricemia and gout. Transport assays showed ATP-dependent transport of urate via ABCG2. Kinetic analysis revealed that ABCG2 mediates high-capacity transport of urate (Km: 8.24 ± 1.44 mM) even under high-urate conditions. Mutation analysis of ABCG2 in 90 Japanese hyperuricemia patients detected six nonsynonymous mutations, including five dysfunctional variants. Two relatively frequent dysfunctional variants, Q126X and Q141K, were then examined. Quantitative trait locus analysis of 739 Japanese individuals showed that Q141K increased SUA as the number of minor alleles of Q141K increased (p = 6.60 × 10?5). Haplotype frequency analysis revealed that there is no simultaneous presence of Q126X and Q141K in one haplotype. Becuase Q126X and Q141K are assigned to nonfunctional and half-functional haplotypes, respectively, their genotype combinations are divided into four functional groups. The association study with 161 male gout patients and 865 male controls showed that all of those with dysfunctional ABCG2 increased the gout risk, especially those with ≤1/4 function (OR, 25.8; 95% CI, 10.3–64.6; p = 3.39 × 10?21). These genotypes were found in 10.1% of gout patients, but in only 0.9% of control. Our function-based clinicogenetic (FBCG) analysis showed that combinations of the two dysfunctional variants are major causes of gout, thereby providing a new approach for prevention and treatment of the gout high-risk population.  相似文献   
93.
94.
The absence of the larval Anisakis simplex s. l. in samples from central Chile but heavy infections in fish from southern localities suggest the existence of two stocks of Strangomera bentincki, one closely associated with the central coast of Chile (landing port San Antonio and Talcahuano, c. 33° 30′ S–36° 40′ S) and the other associated with southern Chile (landing port Puerto Montt, c. 41° 30′ S). Results confirm the usefulness of metazoan parasites, like A. simplex s. l. as biological markers.  相似文献   
95.
The replicon model has initiated a major research line in molecular biology: the study of DNA replication mechanisms. Until now, the majority of studies have focused on a limited set of model organisms, mainly from Bacteria or Opisthokont eukaryotes (human, yeasts) and a few viral systems. However, molecular evolutionists have shown that the living world is more complex and diverse than believed when the operon model was proposed. Comparison of DNA replication proteins in the three domains, Archaea, Bacteria, and Eukarya, have surprisingly revealed the existence of two distinct sets of non-homologous cellular DNA replication proteins, one in Bacteria and the other in Archaea and Eukarya, suggesting that the last universal common ancestor possibly still had an RNA genome. A major puzzle is the presence in eukaryotes of the unfaithful DNA polymerase alpha (Pol α) to prime Okazaki fragments. Interestingly, Pol α is specifically involved in telomere biosynthesis, and its absence in Archaea correlates with the absence of telomeres. The recent discovery of telomere-like GC quartets in eukaryotic replication origins suggests a link between Pol α and the overall organization of the eukaryotic chromosome. As previously proposed by Takemura, Pol α might have originated from a mobile element of viral origin that played a critical role in the emergence of the complex eukaryotic genomes. Notably, most large DNA viruses encode DNA replication proteins very divergent from their cellular counterparts. The diversity of viral replication machineries compared to cellular ones suggests that DNA and DNA replication mechanisms first originated and diversified in the ancient virosphere, possibly explaining why they are so many different types of replication machinerie.  相似文献   
96.
The paper presents data of investigation on the physico‐chemical and antigenic properties of capsid proteins of the Bean common mosaic virus isolated from Phaseolus plants in the Russian Far East (BCMV‐R) and from China (BCMV‐C). A method for isolation of the virus preparation was selected. The purified preparations of two isolates BCMV have been obtained. The presence of one polypeptide in structural proteins of virions was established and their molecular masses determined (BCMV‐R ‐ 31,6 kD; BCMV‐C ‐ 32,1 kD). Polyclonal antiserum was obtained with titre 1:12800 and the indirect and “sandwich"‐variants of ELISA were developed to detect this virus. The allied relationships were established with the bean yellow mosaic virus and with the type representative of the genus Potyvirus ‐ PVY. Based on the data of physico‐chemical and antigenic properties it was concluded that isolates BCMV‐R and BCMV‐C are two independent strains of this virus. The presence of strain‐, virus‐ and genusspecific epitopes of capsid proteine was revealed as a result of comparison of antigenic characteristics of the Russian Far Eastern and Chinese strains of BCMV. A high antigenic activity of capsid protein of the Russian Far Eastern strain was observed.  相似文献   
97.
Meloidoyne incognita (root-knot nematode) and Fusarium solani (root-rot pathogen) were the common soil-borne pathogens and cause severe damage to bean plants in newly reclaimed sandy soil in Nubaryia district, Behera Governorate, Egypt. The antagonistic effects of Trichoderma album and Trichoderma viride as well as three commercial products namely Rhizo-N® (Bacillus subtilis), Bio-Arc® 6% (Bacillus megaterium) and Bio-Zeid® 2.5% (T. album) were tested against M. incognita and F. solani under naturally infected field conditions. T. album and T. viride highly reduced the frequency (%) population of pathogenic fungi such as Fusarium spp., F. solani and Rhizoctonia spp., than the commercial products. Results indicated that all the tested bio-control agents reduced, significantly, the nematode criteria as evidenced by the number of juvenile (J2) in soil and number of galls and egg masses on roots of common bean and Fusarium root-rot incidence (%). Rhizo-N® highly reduced the number of J2 in soil, while T. album was the best in reducing the number of galls and egg masses in roots. The bio-control agents also increased the plant growth parameters of common bean plants i.e. plant height, plant weight, branch no./plant, pods no./plant, pod weight/plant, pod weight, seeds no./plant, fresh seeds weight/pod, dry seeds weight/pod and dry weight of 100 seeds.  相似文献   
98.
Different viral diseases infect common bean crops in Iran. A total of 248 symptomatic samples were collected from common bean fields throughout main growing fields of Guilan province in Iran during the summer of 2006. Eight viruses were detected using double antibody-sandwich – enzyme-linked immunosorbent assay (DAS-ELISA). Bean common mosaic virus – BCMV (1%), Bean leaf roll virus – BLRV (9%), Cowpea mild mottle virus – CpMMV (6%), Southern bean mosaic virus – SBMV (3%), Cucumber mosaic virus – CMV (15%), Bean golden mosaic virus – BGMV (2%), Bean common mosaic necrosis virus – BCMNV (1%) and Bean yellow mosaic virus – BYMV (1%) were detected. Comparatively CMV (15%) was found to be more prevalent in Guilan province. Multiple infections of viruses were recorded in many samples. Weed species belonging to Chenopodiaceae, Solanaceae, Malvaceae and Amaranthaceae families were also found to be infected with the viruses.  相似文献   
99.
Phylogenetic analyses of three families of arthropod apyrases were used to reconstruct the evolutionary relationships of salivary-expressed apyrases, which have an anti-coagulant function in blood-feeding arthropods. Members of the 5′nucleotidase family were recruited for salivary expression in blood-feeding species at least five separate times in the history of arthropods, while members of the Cimex-type apyrase family have been recruited at least twice. In spite of these independent events of recruitment for salivary function, neither of these families showed evidence of convergent amino acid sequence evolution in salivary-expressed members. On the contrary, in the 5′-nucleotide family, salivary-expressed proteins conserved ancestral amino acid residues to a significantly greater extent than related proteins without salivary function, implying parallel evolution by conservation of ancestral characters. This unusual pattern of sequence evolution suggests the hypothesis that purifying selection favoring conservation of ancestral residues is particularly strong in salivary-expressed members of the 5′-nucleotidase family of arthropods because of constraints arising from expression within the vertebrate host.  相似文献   
100.
Apelin is an endogenous ligand of G protein-coupled receptor-apelin and angiotensin-1-like receptor (APJ). The biological effects of apelin–APJ system are reported in multiple systems including cardiovascular, endocrinal, and gastrointestinal system. Previous studies had shown that apelin-13 is a potential protective agent on cardiac ischemia; however, the role of apelin in the central nervous system remained unknown. In this study, we investigated therapeutic effects of apelin-36, a long form of apelin, in ischemic brain injury models. We found that apelin-36 reduced cerebral infarct volume in the middle cerebral artery occlusion (MCAO) model and the neonatal hypoxic/ischemic (H/I) injury model. Apelin-36 improved neurological deficits in the MCAO model and promoted long-term functional recovery after H/I brain injury. We further explored the protective mechanisms of apelin-36 on H/I brain injury. We clearly demonstrated that apelin-36 significantly reduced the levels of cleaved caspase-3 and Bax, two well-established apoptotic markers after H/I injury, indicating the anti-apoptotic activity of apelin-36 in ischemic injury. Since apelin-36 increased the level of phosphorylated Akt after H/I injury, we treated neonates with a specific PI3K inhibitor LY294002. We found that LY294002 decreased the phosphorylated Akt level and attenuated protective effects of apelin-36 on apoptosis. These suggested that the PI3K/Akt pathway was at least in part involved in the anti-apoptotic mechanisms of apelin-36. Our findings demonstrated that apelin-36 was a promising therapeutic agent on the treatment of ischemic brain injury.  相似文献   
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