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921.
Gout is a urate deposition disease caused by persistent hyperuricemia. Because gout patients present with a variety of clinical symptoms, it is necessary to have a guideline for the standard management and care of gout and hyperuricemia. The Japanese Society of Gout and Nucleic Acid Metabolism, a scientific society committed to study nucleic acid metabolism and related diseases, established the first edition of the "Guideline for the Management of Hyperuricemia and Gout" in 2002, and published the revised version in January 2010. This second edition is not only evidence based on a search of systemic literature, but also includes consensus levels by a Delphi exercise to determine the strength of the recommendations. A draft version of this guideline was reviewed by internal and external reviewers as well as a patient. In this guideline, key messages from each chapter are listed as statements together with the evidence level, consensus level, and strength of the recommendation. In this proceeding, several selected chapters on the clinical management of gout and hyperuricemia are described. We hope this guideline is appropriately used for the standard management and care of patients with hyperuricemia and gout in daily practice.  相似文献   
922.
UV-B irradiation is one of the risk factors in age-related diseases. We have reported that biologically uncommon D-β-Asp residues accumulate in proteins from sun-exposed elderly human skin. A previous study also reported that carboxymethyl lysine (CML; one of the advanced glycation end products (AGEs)) which is produced by the oxidation of glucose and peroxidation of lipid, also increases upon UV B irradiation. The formation of D-β-Asp and CML were reported as the alteration of proteins in UV B irradiated skin, independently. In this study, in order to clarify the relationship between the formation of D-β-Asp and CML, immunohistochemical analysis using anti-D-β-Asp containing peptide antibodies and anti-CML antibodies was performed in UV B irradiated mice. Immunohistochemical analyses clearly indicated that an anti-D-β-Asp containing peptide antibody and anti-CML antibody reacted at a common area in UV B irradiated skin. Western blot analyses of the proteins isolated from UV B irradiated skin demonstrated that proteins of 50-70 kDa were immunoreactive towards antibodies for both D-β-Asp containing peptide and CML. These proteins were identified by proteomic analysis as members of the keratin families including keratin-1, keratin-6B, keratin-10, and keratin-14.  相似文献   
923.
We evaluated the molecular, anatomical and physiological properties of a soybean line transformed to improve drought tolerance with an rd29A:AtDREB1A construct. This construct expressed dehydration- responsive element binding protein DREB1A from the stress-inducible rd29A promoter. The greenhouse growth test included four randomized blocks of soybean plants, with each treatment performed in triplicate. Seeds from the non-transformed soybean cultivar BR16 and from the genetically modified soybean P58 line (T(2) generation) were grown at 15% gravimetric humidity for 31 days. To induce water deficit, the humidity was reduced to 5% gravimetric humidity (moderate stress) for 29 days and then to 2.5% gravimetric humidity (severe stress). AtDREB1A gene expression was higher in the genetically modified P58 plants during water deficit, demonstrating transgene stability in T(2) generations and induction of the rd29A promoter. Drought-response genes, including GmPI-PLC, GmSTP, GmGRP, and GmLEA14, were highly expressed in plants submitted to severe stress. Genetically modified plants had higher stomatal conductance and consequently higher photosynthetic and transpiration rates. In addition, they had more chlorophyll. Overexpression of AtDREB1A may contribute to a decrease in leaf thickness; however, a thicker abaxial epidermis was observed. Overexpression of AtDREB1A in soybean appears to enhance drought tolerance.  相似文献   
924.
Photosensitivity plays an essential role in the response of plants to their changing environments throughout their life cycle. In soybean [Glycine max (L.) Merrill], several associations between photosensitivity and maturity loci are known, but only limited information at the molecular level is available. The FT3 locus is one of the quantitative trait loci (QTL) for flowering time that corresponds to the maturity locus E3. To identify the gene responsible for this QTL, a map-based cloning strategy was undertaken. One phytochrome A gene (GmPhyA3) was considered a strong candidate for the FT3 locus. Allelism tests and gene sequence comparisons showed that alleles of Misuzudaizu (FT3/FT3; JP28856) and Harosoy (E3/E3; PI548573) were identical. The GmPhyA3 alleles of Moshidou Gong 503 (ft3/ft3; JP27603) and L62-667 (e3/e3; PI547716) showed weak or complete loss of function, respectively. High red/far-red (R/FR) long-day conditions enhanced the effects of the E3/FT3 alleles in various genetic backgrounds. Moreover, a mutant line harboring the nonfunctional GmPhyA3 flowered earlier than the original Bay (E3/E3; PI553043) under similar conditions. These results suggest that the variation in phytochrome A may contribute to the complex systems of soybean flowering response and geographic adaptation.FLOWERING represents the transition from the vegetative to the reproductive phase in plants. Various external cues, such as photoperiod and temperature, are known to initiate plant flowering under the appropriate seasonal conditions. Of these cues, light is the most important, being received by several photoreceptors, including the red light (R) and the far-red light (FR)-absorbing phytochromes and the blue/UV-A absorbing cryptochromes and phototorpins (Chen et al. 2004).Phytochrome is the best characterized of these photoreceptors. All higher plant phytochromes are thought to exist as specific dimer combinations (Sharrock and Clack 2004), with each monomer being attached to a light-absorbing linear tetrapyrrole, phytochromobilin. The phytochrome apoproteins are synthesized within the cytosol and assemble autocatalytically with a chromophore to form the phytochrome holoproteins. The R-absorbing form (Pr) is thought to be inactive but is then converted to the active FR-absorbing form (Pfr) by R absorption. The absorption of light triggers the transfer of the phytochrome to the nucleus, where it regulates gene expression. In most plant species, the phytochrome apoproteins are encoded by a small gene family. Type I phytochrome is degraded in the light and is abundant in dark-grown seedlings, whereas type II phytochrome is relatively stable in the light (reviewed by Bae and Choi 2008). In Arabidopsis, five phytochromes (PhyA–E) have been characterized (Clack et al. 1994; Quail et al. 1995). PhyA is type I and is responsible for the very low fluence response and high irradiance response, whereas the other phytochromes are type II and are responsible for red-far/red reversible low fluence response (reviewed by Whitelam et al. 1998).It is well known that mutations in the phytochrome A gene affect the photoperiodic control of flowering. In Arabidopsis, a phyA mutant flowered later in either long-day or short-day conditions with a night break (Johnson et al. 1994; Reed et al. 1994). In rice, combinations of mutant alleles of phytochrome genes conferred various effects on the flowering phenotype. For example, the phyA phyB and phyA phyC double mutants grown under natural-day-length conditions showed earlier flowering phenotypes than wild-type plants (Takano et al. 2005). In pea, a long-day plant, loss- or gain-of-function phyA mutants displayed late or early flowering phenotypes, respectively (Weller et al. 1997, 2001). It is likely that photoperiodic response via phyA signaling is important for crop adaptation to a wide range of growing conditions.In soybean [Glycine max (L.) Merrill], several maturity loci, designated as E loci (Cober et al. 1996a), have been characterized by classical methods. These are E1 and E2 (Bernard 1971), E3 (Buzzell 1971), E4 (Buzzell and Voldeng 1980), E5 (McBlain and Bernard 1987), E6 (Bonato and Vello 1999), and E7 (Cober and Voldeng 2001). Of these, the E1, E3, and E4 loci have been suggested to be related to photoperiod sensitivity under various light conditions (Saidon et al. 1989; Cober et al. 1996b; Abe et al. 2003). In previous studies, using the same populations as in this study, three flowering-time quantitative trait loci (QTL)—FT1, FT2, and FT3 loci—were identified and considered to be identical with the maturity loci E1, E2, and E3, respectively (Yamanaka et al. 2001; Watanabe et al. 2004). Although many loci related to soybean flowering and maturity have been identified, and some candidate genes were recognized using near isogenic lines (NILs) (Tasma and Shoemaker 2003), most of the genes responsible for these loci have not yet been isolated except for the E4 gene. Liu et al. (2008) reported an association between phytochrome A and photoperiod sensitivity. A retrotransposon sequence inserted into the exon of the e4 allele conferred an early flowering phenotype under long-day conditions extended by incandescent lighting.A relationship between the E3 gene and some photoreceptor genes was suggested from different photosensitivity responses of various soybean NILs (Cober et al. 1996a). Cober and Voldeng (1996) also reported a linkage relationship between the E3 and Dt1 loci, which is related to a determinate or indeterminate growth habit phenotype. Additionally, Molnar et al. (2003) reported that Satt229, on linkage group (LG) L, was a proximal simple sequence repeat (SSR) marker to the E3 loci. According to the Soybean Genome Database (Shultz et al. 2006a,b, 2007; http://soybeangenome.siu.edu/) and the Legume Information System (LIS; http://www.comparative-legumes.org/), there are numerous QTL and >60 loci associated with various agronomic traits in the region between Dt1 and Satt373 (∼30–40 cM). This extremely large number of QTL may be the result of linkage between the Dt1 and E3 loci because both loci can affect many aspects of plant morphology. Among these QTL, several associations with the E3 gene have been reported (Mansur et al. 1996; Orf et al. 1999; Funatsuki et al. 2005; Kahn et al. 2008).To identify the genes responsible for the target QTL, fine mapping and map-based cloning strategies are necessary (Salvi and Tuberosa 2005). QTL analysis using intercross-derived populations, such as F2 and recombinant inbred lines (RILs), have some limitations in genome resolution (10–30 cM) because of the simultaneous segregation of several loci affecting the same trait (Kearsey and Farquhar 1998). Additional strategies are therefore required to locate QTL more precisely. The use of NILs that differ at a single QTL is an effective approach for fine mapping and characterization of an individual locus (Salvi and Tuberosa 2005). However, the development of NILs through repeated backcrossing is time-consuming and laborious (Tuinstra et al. 1997). The use of a residual heterozygous line (RHL), as proposed by Yamanaka et al. (2004), and which is derived from RIL, is a powerful tool for precisely evaluating QTL (Haley et al. 1994). An RHL harbors a heterozygous region where the target QTL is located and a homozygous background in most other regions of the genome. Tuinstra et al. (1997) used a similar term, heterogeneous inbred family, for a selfed RHL population to identify the QTL associated with seed weight in sorghum.This RHL strategy has already been used to identify loci underlying resistance to pathogens in soybean (Njiti et al. 1998; Meksem et al. 1999; Triwitayakorn et al. 2005). After identification of the target loci, novel DNA markers tightly linked to the loci were developed using the amplified fragment length polymorphism (AFLP) method (Meksem et al. 2001a,b). Physical contigs, screened by sequence-characterized amplified region (SCAR) markers converted from these AFLP fragments, are ideal sources for identifying candidate genes for the target traits (Ruben et al. 2006).The aim of this study is to characterize the FT3 locus using a map-based cloning strategy and to confirm the gene responsible for the E3/FT3 locus by allelism tests through comparisons of gene sequences and photosensitivity of several alleles.  相似文献   
925.
We have optimized a simple and rapid preparation procedure for mushroom DNA extraction from colonies on media or from fruiting bodies for PCR amplification. The protocol combines microwaving twice for 1 min, cooling for 10 min, and centrifuging for 5 min. By using this procedure, more than 100 samples of mushroom DNA can be prepared within 1 h. The DNA obtained can be used for (1) identifying mushroom species by PCR and subsequent sequencing, (2) amplifying low copy number genes (at least 2,000 bp), and (3) screening genetic transformants. This technique will contribute to the mycology of mushroom species.  相似文献   
926.
Rheumatoid arthritis is an autoimmune disease with a complex etiology, leading to inflammation of synovial tissue and joint destruction. Through a genome-wide association study (GWAS) and two replication studies in the Japanese population (7,907 cases and 35,362 controls), we identified two gene loci associated with rheumatoid arthritis susceptibility (NFKBIE at 6p21.1, rs2233434, odds ratio (OR) = 1.20, P = 1.3×10−15; RTKN2 at 10q21.2, rs3125734, OR = 1.20, P = 4.6×10−9). In addition to two functional non-synonymous SNPs in NFKBIE, we identified candidate causal SNPs with regulatory potential in NFKBIE and RTKN2 gene regions by integrating in silico analysis using public genome databases and subsequent in vitro analysis. Both of these genes are known to regulate the NF-κB pathway, and the risk alleles of the genes were implicated in the enhancement of NF-κB activity in our analyses. These results suggest that the NF-κB pathway plays a role in pathogenesis and would be a rational target for treatment of rheumatoid arthritis.  相似文献   
927.
928.
Estimation of fish biomass using environmental DNA   总被引:5,自引:0,他引:5  
Environmental DNA (eDNA) from aquatic vertebrates has recently been used to estimate the presence of a species. We hypothesized that fish release DNA into the water at a rate commensurate with their biomass. Thus, the concentration of eDNA of a target species may be used to estimate the species biomass. We developed an eDNA method to estimate the biomass of common carp (Cyprinus carpio L.) using laboratory and field experiments. In the aquarium, the concentration of eDNA changed initially, but reached an equilibrium after 6 days. Temperature had no effect on eDNA concentrations in aquaria. The concentration of eDNA was positively correlated with carp biomass in both aquaria and experimental ponds. We used this method to estimate the biomass and distribution of carp in a natural freshwater lagoon. We demonstrated that the distribution of carp eDNA concentration was explained by water temperature. Our results suggest that biomass data estimated from eDNA concentration reflects the potential distribution of common carp in the natural environment. Measuring eDNA concentration offers a non-invasive, simple, and rapid method for estimating biomass. This method could inform management plans for the conservation of ecosystems.  相似文献   
929.
Washed cells (62?mg) of Kitasatospora sp. GF12 in 4?ml buffer (pH 7) catalyzed the regioselective hydroxylation of 60?mM 1,3-adamantanediol [1,3-ad(OH)(2)] to 30.9?mM 1,3,5-adamantanetriol [1,3,5-ad(OH)(3)] over 120?h at 24?°C. Glycerol at 400?mM was added to the reaction mixture to recycle the intracellular NADH/NADPH. Whole cells of GF12, also catalyzed the hydroxylation of 10?mM 1-adamantanol (1-adOH), to 3.6?mM 1,3,5-ad(OH)(3).  相似文献   
930.
Human DNA polymerase kappa (pol κ) is a translesion synthesis (TLS) polymerase that catalyzes TLS past various minor groove lesions including N 2-dG linked acrolein- and polycyclic aromatic hydrocarbon-derived adducts, as well as N 2-dG DNA–DNA interstrand cross-links introduced by the chemotherapeutic agent mitomycin C. It also processes ultraviolet light-induced DNA lesions. Since pol κ TLS activity can reduce the cellular toxicity of chemotherapeutic agents and since gliomas overexpress pol κ, small molecule library screens targeting pol κ were conducted to initiate the first step in the development of new adjunct cancer therapeutics. A high-throughput, fluorescence-based DNA strand displacement assay was utilized to screen ∼16,000 bioactive compounds, and the 60 top hits were validated by primer extension assays using non-damaged DNAs. Candesartan cilexetil, manoalide, and MK-886 were selected as proof-of-principle compounds and further characterized for their specificity toward pol κ by primer extension assays using DNAs containing a site-specific acrolein-derived, ring-opened reduced form of γ-HOPdG. Furthermore, candesartan cilexetil could enhance ultraviolet light-induced cytotoxicity in xeroderma pigmentosum variant cells, suggesting its inhibitory effect against intracellular pol κ. In summary, this investigation represents the first high-throughput screening designed to identify inhibitors of pol κ, with the characterization of biochemical and biologically relevant endpoints as a consequence of pol κ inhibition. These approaches lay the foundation for the future discovery of compounds that can be applied to combination chemotherapy.  相似文献   
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