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1.
Pentachlorophenol (PCP) has been widely used as a pesticide in paddy fields and has imposed negative ecological effect on agricultural soil systems, which are in typically anaerobic conditions. In this study, we investigated the effect of repeated additions of PCP to paddy soil on the microbial communities under anoxic conditions. Acetate was added as the carbon source to induce and accelerate cycles of the PCP degradation. A maximum degradation rate occurred at the 11th cycle, which completely transformed 32.3 μM (8.6 mg L?1) PCP in 5 days. Illumina high throughput sequencing of 16S rRNA gene was used to profile the diversity and abundance of microbial communities at each interval and the results showed that the phyla of Bacteroidates, Firmicutes, Proteobacteria, and Euryarchaeota had a dominant presence in the PCP-dechlorinating cultures. Methanosarcina, Syntrophobotulus, Anaeromusa, Zoogloea, Treponema, W22 (family of Cloacamonaceae), and unclassified Cloacamonales were found to be the dominant genera during PCP dechlorination with acetate. The microbial community structure became relatively stable as cycles increased. Treponema, W22, and unclassified Cloacamonales were firstly observed to be associated with PCP dechlorination in the present study. Methanosarcina that have been isolated or identified in PCP dechlorination cultures previously was apparently enriched in the PCP dechlorination cultures. Additionally, the iron-cycling bacteria Syntrophobotulus, Anaeromusa, and Zoogloea were enriched in the PCP dechlorination cultures indicated they were likely to play an important role in PCP dechlorination. These findings increase our understanding for the microbial and geochemical interactions inherent in the transformation of organic contaminants from iron rich soil, and further extend our knowledge of the PCP-transforming microbial communities in anaerobic soil conditions.  相似文献   

2.
The expression profile of the ZEB1, ZEB2, VIM, CDH1, SFRP2, FOXQ1, TNC, MACC1, PLS3, CFTR, FLNA, MUC2, TFF3, and RARRES3 genes, as well as the mutational status of the KRAS, NRAS, BRAF, and PIK3CA genes, were investigated in 40 patients with colorectal cancer and liver metastases. A comparative analysis of changes in gene expression in primary tumor cells and liver metastases was performed. Statistically significant differences were found between the expression levels of the ZEB2 (p = 0.004), VIM (p < 0.001), FLNA (p = 0.04), and MUC2 (p < 0.001) genes. It was demonstrated that the overall frequency of mutations of the KRAS gene was 18/40 (45%) and the PIK3CA gene was 9/40 (23%). Mutations in the NRAS and BRAF genes were not found. The concordance between the primary tumor and metastases in the liver by mutation status was 100%.  相似文献   

3.
The concentration of HCO 3 ? , pH, pO2, sO2, and pCO2 were measured in the total umbilical blood of neonates born in January–February (n = 169) and June–July (n = 172). The former group displayed higher values of pH, pO2, and sO2, whereas pCO2 and the concentration of HCO 3 ? were higher in the latter group. There was a 70–80% coincidence of the variants in both groups (the regions of statistical transgressions); seasonal factors were responsible for 20–30% of the differences.  相似文献   

4.
The ligand field density functional theory (LFDFT) algorithm is extended to treat the electronic structure and properties of systems with three-open-shell electron configurations, exemplified in this work by the calculation of the core and semi-core 1s, 2s, and 3s one-electron excitations in compounds containing transition metal ions. The work presents a model to non-empirically resolve the multiplet energy levels arising from the three-open-shell systems of non-equivalent ns, 3d, and 4p electrons and to calculate the oscillator strengths corresponding to the electric-dipole 3d m  → ns 13d m 4p 1 transitions, with n = 1, 2, 3 and m = 0, 1, 2, …, 10 involved in the s electron excitation process. Using the concept of ligand field, the Slater-Condon integrals, the spin-orbit coupling constants, and the parameters of the ligand field potential are determined from density functional theory (DFT). Therefore, a theoretical procedure using LFDFT is established illustrating the spectroscopic details at the atomic scale that can be valuable in the analysis and characterization of the electronic spectra obtained from X-ray absorption fine structure or electron energy loss spectroscopies.  相似文献   

5.
6.
The cytochrome b 6 f complex of oxygenic photosynthesis produces substantial levels of reactive oxygen species (ROS). It has been observed that the ROS production rate by b 6 f is 10–20 fold higher than that observed for the analogous respiratory cytochrome bc1 complex. The types of ROS produced (O2??, 1O2, and, possibly, H2O2) and the site(s) of ROS production within the b 6 f complex have been the subject of some debate. Proposed sources of ROS have included the heme b p , PQ p ?? (possible sources for O2??), the Rieske iron–sulfur cluster (possible source of O2?? and/or 1O2), Chl a (possible source of 1O2), and heme c n (possible source of O2?? and/or H2O2). Our working hypothesis is that amino acid residues proximal to the ROS production sites will be more susceptible to oxidative modification than distant residues. In the current study, we have identified natively oxidized amino acid residues in the subunits of the spinach cytochrome b 6 f complex. The oxidized residues were identified by tandem mass spectrometry using the MassMatrix Program. Our results indicate that numerous residues, principally localized near p-side cofactors and Chl a, were oxidatively modified. We hypothesize that these sites are sources for ROS generation in the spinach cytochrome b 6 f complex.  相似文献   

7.
8.
Retinoic acid (RA) plays an important role in vertebrate development and regeneration. RA signalling directly regulates the expression of Hox genes, being in this way involved in the patterning of the anterior-posterior (AP) axis of vertebrate embryos. So far the relationship between retinoic acid signalling and Hox genes has been shown only for chordates. In this study we incubated juvenile worms and regenerating worms of two polychaete species from the family Nereididae, Alitta virens and Platynereis dumerilii, with all-trans-retinal, the precursor of retinoic acid. Under the influence of all-trans-retinal the anterior expression boundary of Post2 Нох gene shifted towards the anterior end both in intact and in regenerating worms of both species. Our data indicate the existence of a relationship between RA signalling and Нох genes in Protostomia.  相似文献   

9.

Objectives

To prepare (R)-phenyl-1,2-ethanediol ((R)-PED) with high enantiomeric excess (ee p) and yield from racemic styrene oxide (rac-SO) at high concentration by bi-enzymatic catalysis.

Results

The bi-enzymatic catalysis was designed for enantioconvergent hydrolysis of rac-SO by a pair of novel epoxide hydrolases (EHs), a Vigna radiata EH3 (VrEH3) and a variant (AuEH2A250I) of Aspergillus usamii EH2. The simultaneous addition mode of VrEH3 and AuEH2A250I, exhibiting the highest average turnover frequency (aTOF) of 0.12 g h?1 g?1, was selected, by which rac-SO (10 mM) was converted into (R)-PED with 92.6% ee p and 96.3% yield. Under the optimized reaction conditions: dry weight ratio 14:1 of VrEH3-expressing E. coli/vreh3 to AuEH2A250I-expressing E. coli/Aueh2 A250I and reaction at 20 °C, rac-SO (10 mM) was completely hydrolyzed in 2.3 h, affording (R)-PED with 98% ee p. At the weight ratio 0.8:1 of rac-SO to two mixed dry cells, (R)-PED with 97.4% ee p and 98.7% yield was produced from 200 mM (24 mg/ml) rac-SO in 10.5 h.

Conclusions

Enantioconvergent hydrolysis of rac-SO at high concentration catalyzed by both VrEH3 and AuEH2A250I is an effective method for preparing (R)-PED with high ee p and yield.
  相似文献   

10.
p53 helps in maintaining genomic stability by undergoing cellular arrest, DNA repair or cellular apoptosis during DNA damage. So, as to find the association of p53Arg 72 Pro towards lung carcinogenesis and overall survival of North Indian lung cancer patients, single nucleotide polymorphic variant (rs1042522) was analyzed. 840 subjects including 420 cases and 420 controls were recruited and genotyped using PCR-RFLP technique for p53Arg 72 Pro polymorphic site. Association was analyzed using adjusted odds ratio along with its confidence intervals (95?% CI) and p value predicted from logistic regression whereas overall survival for lung cancer patients was obtained using Kaplan–Meir and Cox regression model for different parameters to obtain hazard ratio and survival time with statistical significance (log-rank p value). None of the variant genotypes for p53Arg 72 Pro showed any association towards lung cancer risk or any specific histological subtype. Lung cancer subjects with Pro/Pro genotype had better median survival time as compared to Arg/Pro genotype (10 months; HR?=?0.65; 95?% CI?=?0.45–0.95; p?=?0.03). Furthermore, female lung cancer patients with Arg/Pro (HR?=?0.08; 95?% CI?=?0.02–0.34; p?=?0.0005) and Pro/Pro (HR?=?0.21; 95?% CI?=?0.06–0.67; p?=?0.008) genotypes showed a better overall survival and hence a better prognosis as compared to males. Our data also reveals that lung cancer patients with ECOG scores between 0 and 1 and carrying the Pro/Pro had better chances of survival. p53 codon 72 polymorphism could play a role as a prognostic marker in lung cancer patients.  相似文献   

11.
The applicability of emission of the N 3Λσ triplet states of molecular hydrogen for spectral diagnostics of the positive column of a dc glow discharge in hydrogen at translational gas temperatures of 360–600 K, specific absorbed powers of 0.8–4.25 W/cm, gas pressures of p = 0.3–15.0 Torr, reduced fields of E/N = 30–130 Td, and electron densities of n e = 4.0 × 109–6.5 × 1010 cm–3 is analyzed by using an advanced level-based semi-empirical collisional?radiative model. It is found that secondary processes make the main contribution to the population and decay of the N 3Λσ = a 3Σ+ g , c 3Π u , g 3Σ+ g , h 3Σ+ g , and i 3Π g triplet states. The dipole-allowed transitions e 3Σ+ g a 3Σ+ g , f 3Σ+ g a 3Σ+ g , g 3Σ+ g and k 3Π u a 3Σ+ g can be used for spectral diagnostics of a dc discharge within a simplified coronal model.  相似文献   

12.
Obesity is a global epidemic characterized not only by excessive fat deposition but also by important complications such as nonalcoholic liver steatosis. Beneficial antiobesogenic effects have been described for some mushrooms. The current study aimed to demonstrate the protective effect of Agaricus bisporus (AB) supplementation against the metabolic alterations induced by high-fat-diet (HFD) feeding. Eight-week-old C57BL/6J mice were fed for 10 weeks with one of the following diets: (1) control diet (n?=?7), (2) HFD (n?=?7), (3) HFD supplemented with 5% AB (n?=?9), and (4) HFD supplemented with 10% AB (n?=?9). A pair-fed group was also included for the 10% AB group (n?=?6). The impact of AB supplementation on food intake, body weight gain, and liver and fat pad weights was examined. Biochemical, histological, and molecular parameters were also analyzed. Dietary supplementation with 10% AB reduced the HFD-induced increase in body, epididymal, and mesenteric fat weights (p?<?0.01, p?<?0.05, and p?<?0.05, respectively). Supplementation with AB also reduced liver damage in a dose-dependent manner (p?<?0.01 and p?<?0.001). This effect was confirmed by histological analysis that showed that liver steatosis was markedly reduced in mice fed with AB. The beneficial properties of 10% AB supplementation appear to be mediated through a decrease in food intake and via stimulation of mesenteric and hepatic free-fatty acid beta-oxidation, along with a decrease in epidydimal and hepatic expression of CD36. In conclusion, supplementation with AB prevents excessive body weight gain and liver steatosis induced by HFD consumption.  相似文献   

13.
The aim of present study was to elucidate the association of CTLA4 +49 A/G and HLA-DRB1*/DQB1* gene polymorphism in south Indian T1DM patients. The patients and controls (n?=?196 each) were enrolled for CTLA4 and HLA-DRB1*/DQB1* genotyping by RFLP/PCR-SSP methods. The increased frequencies of CTLA4 ‘AG’ (OR?=?1.99; p?=?0.001), ‘GG’ (OR?=?3.94; p?=?0.001) genotypes, and ‘G’ allele (OR?=?2.42; p?=?9.26?×?10?8) were observed in patients. Reduced frequencies of ‘AA’ (OR?=?0.35; p?=?7.19?×?10?7) and ‘A’ (OR?=?0.41; p?=?9.26?×?10?8) in patients revealed protective association. Among HLA-DRB1*/DQB1* alleles, DRB1*04 (OR?=?3.29; p?=?1.0?×?10?5), DRB1*03 (OR?=?2.81; p?=?1.9?×?10?6), DQB1*02:01 (OR?=?2.93; p?=?1.65?×?10?5), DQB1*02:02 (OR?=?3.38; p?=?0.0003), and DQB1*03:02 (OR?=?7.72; p?=?0.0003) were in susceptible association. Decreased frequencies of alleles, DRB1*15 (OR?=?0.32; p?=?2.55?×?10?7), DRB1*10 (OR?=?0.45; p?=?0.002), DQB1*06:01 (OR?=?0.43; p?=?0.0001), and DQB1*05:02 (OR?=?0.28; p?=?2.1?×?10?4) in patients were suggested protective association. The combination of DRB1*03+AG (OR?=?5.21; p?=?1.4?×?10?6), DRB1*04+AG (OR?=?2.14; p?=?0.053), DRB1*04+GG (OR?=?5.21; p?=?0.036), DQB1*02:01+AG (OR?=?4.44; p?=?3.6?×?10?5), DQB1*02:02+AG (OR?=?20.9; p?=?9.5?×?10?4), and DQB1*02:02+GG (OR?=?4.06; p?=?0.036) revealed susceptible association. However, the combination of DRB1*10+AA (OR?=?0.35; p?=?0.003), DRB1*15+AA (OR?=?0.22; p?=?5.3?×?10?7), DQB1*05:01+AA (OR?=?0.45; p?=?0.007), DQB1*05:02+AA (OR?=?0.17; p?=?1.7?×?10?4), DQB1*06:01+AA (OR?=?0.40; p?=?0.002), and DQB1*06:02+AG (OR?=?0.34; p?=?0.001) showed decreased frequency in patients, suggesting protective association. In conclusion, CTLA4/HLA-DR/DQ genotypic combinations revealed strong susceptible/protective association toward T1DM in south India. A female preponderance in disease associations was also documented.  相似文献   

14.
Results from works involving the study of hetero-and homozygous interaction of the keeping quality genes alc, nor, and rin in tomato plants are presented. It is shown that cumulative polymery leading to the formation of a new “long ripening” phenotype is observed in the double heterozygotes alc/alc +//nor/nor +, nor/nor +//rin/rin +, and alc/alc +//rin/rin +. Strong inhibition of processes of ripeness and synthesis of carotenoids occurs with nonallelic interaction in the double homozygotes alc/alc//rin/rin, nor/nor//rin/rin, and alc/alc//nor/nor. This promotes the formation of a new “non-ripening” phenotype with the absence of visual signs of ripeness, i.e., a whitish-green coloring of the fruit.  相似文献   

15.
16.
The genetic structure of susceptibility to type 1 diabetes (T1D) in the population of Tomsk was studied. We had a group of T1D patients (N = 285) and a population sample (N = 300) and we studied 58 SNPs localized in the 47 genes which products are involved in various metabolic pathways and processes as fibrogenesis, endothelial dysfunction, and inflammation. Genotyping was performed by mass spectrometry using the Sequenom MassARRAY system (United States). We compared the group of T1D patients and the population sample and found an association with the predisposition to disease for seven markers: rs3765124 of the ADAMDEC1 gene, genotype AA (p = 0.004), allele A (p = 0.033); rs1007856 of the ITGB5 gene, genotype TT (p = 0.015), allele T (p = 0.036); rs20579 of the LIG1 gene, genotype CC (p = 0.004), allele C (p = 0.002); rs12980602 of the IFNL2 gene, allele C (p = 0.029); rs4986819 of the PARP4 gene, allele C (p = 0.044); rs1143674 of the ITGA4 gene genotype GG (p = 0.002); rs679620 of the MMP3 gene, genotype AA (p = 0.008). Thus, the products of genes associated with T1D belong to different molecular classes: metalloproteases (ADAMDEC1, MMP3), cytokines (IL28A), cell surface receptors (ITGA4), adhesion molecules (ITGB5), DNA ligases (LIG1), and ribosyltransferase enzymes (PARP4). The ADAMDEC1, ITGA4, and ITGB5 genes belong to two biological processes: cell communication and signal transduction. The LIG1 and PARP4 genes regulate the metabolism of nucleic acids, MMP3 is involved in the regulation of protein metabolism, and the IFNL2 is involved in the immune response.  相似文献   

17.

Background

The standard approach to determine unique or shared genetic factors across populations is to identify risk alleles in one population and investigate replication in others. However, since populations differ in DNA sequence information, allele frequencies, effect sizes, and linkage disequilibrium patterns, SNP association using a uniform stringent threshold on p values may not be reproducible across populations. Here, we developed rank-based methods to investigate shared or population-specific loci and pathways for childhood asthma across individuals of diverse ancestry. We performed genome-wide association studies on 859,790 SNPs genotyped in 527 affected offspring trios of European, African, and Hispanic ancestry using publically available asthma database in the Genotypes and Phenotypes database.

Results

Rank-based analyses showed that there are shared genetic factors for asthma across populations, more at the gene and pathway levels than at the SNP level. Although the top 1,000 SNPs were not shared, 11 genes (RYR2, PDE4D, CSMD1, CDH13, ROBO2, RBFOX1, PTPRD, NPAS3, PDE1C, SEMA5A, and CTNNA2) mapped by these SNPs were shared across populations. Ryanodine receptor 2 (RYR2, a statin response-related gene) showed the strongest association in European (p value?=?2.55?×?10?7) and was replicated in African (2.57?×?10?4) and Hispanic (1.18?×?10?3) Americans. Imputation analyses based on the 1000 Genomes Project uncovered additional RYR2 variants associated with asthma. Network and functional ontology analyses revealed that RYR2 is an integral part of dermatological or allergic disorder biological networks, specifically in the functional classes involving inflammatory, eosinophilic, and respiratory diseases.

Conclusion

Our rank-based genome-wide analysis revealed for the first time an association of RYR2 variants with asthma and replicated previously discovered PDE4D asthma gene across human populations. The replication of top-ranked asthma genes across populations suggests that such loci are less likely to be false positives and could indicate true associations. Variants that are associated with asthma across populations could be used to identify individuals who are at high risk for asthma regardless of genetic ancestry.
  相似文献   

18.
One important mechanism plants use to cope with salinity is keeping the cytosolic Na+ concentration low by sequestering Na+ in vacuoles, a process facilitated by Na+/H+ exchangers (NHX). There are eight NHX genes (NHX1 through NHX8) identified and characterized in Arabidopsis thaliana. Bioinformatics analyses of the known Arabidopsis genes enabled us to identify six Medicago truncatula NHX genes (MtNHX1, MtNHX2, MtNHX3, MtNHX4, MtNHX6, and MtNHX7). Twelve transmembrane domains and an amiloride binding site were conserved in five out of six MtNHX proteins. Phylogenetic analysis involving A. thaliana, Glycine max, Phaseolus vulgaris, and M. truncatula revealed that each individual MtNHX class (class I: MtNHX1 through 4; class II: MtNHX6; class III: MtNHX7) falls under a separate clade. In a salinity-stress experiment, M. truncatula exhibited ~?20% reduction in biomass. In the salinity treatment, sodium contents increased by 178 and 75% in leaves and roots, respectively, and Cl? contents increased by 152 and 162%, respectively. Na+ exclusion may be responsible for the relatively smaller increase in Na+ concentration in roots under salt stress as compared to Cl?. Decline in tissue K+ concentration under salinity was not surprising as some antiporters play an important role in transporting both Na+ and K + . MtNHX1, MtNHX6, and MtNHX7 display high expression in roots and leaves. MtNHX3, MtNHX6, and MtNHX7 were induced in roots under salinity stress. Expression analysis results indicate that sequestering Na+ into vacuoles may not be the principal component trait of the salt tolerance mechanism in M. truncatula and other component traits may be pivotal.  相似文献   

19.
The effect of percent relative humidity (16–84% RH), moisture content (4.2–6.5% w/w MC), and compression force (4.9–44.1 kN CF) on the light-induced fluorescence (LIF) response of 10% w/w active pharmaceutical ingredient (API) compacts is reported. The fluorescent response was evaluated using two separate central composite designs of experiments. The effect of % RH and CF on the LIF signal was highly significant with an adjusted R 2 ?=?0.9436 and p?<?0.0001. Percent relative humidity (p?=?0.0022), CF (p?<?0.0001), and % RH2 (p?=?0.0237) were statistically significant factors affecting the LIF response. The effects of MC and CF on LIF response were also statistically significant with a p value <0.0001 and adjusted R 2 value of 0.9874. The LIF response was highly impacted by MC (p?<?0.0001), CF (p?<?0.0001), and MC2 (p?=?0022). At 10% w/w API, increased % RH, MC, and CF led to a nonlinear decrease in LIF response. The derived quadratic model equations explained more than 94% of the data. Awareness of these effects on LIF response is critical when implementing LIF as a process analytical tool.  相似文献   

20.
Aquatic vegetation of Hydrochari-Lemnetea and Potametea classes in the Danube-Tisza-Danube hydrosystem (Hs DTD) was studied in 2009–2012, by applying the standard Braun-Blanquet method. The canal network vegetation comprises 14 associations, with Trapetum natantis and Ceratophylletum demersi being the most widely distributed. Hs DTD is also a habitat for several important endangered species, which serve as edificators of the following phytocenoses: Nymphaeetum albae, Nymphaeetum albo-luteae, Nymphoidetum peltatae, Trapetum natantis, Lemno-Spirodeletum, Salvinio-Spirodeletum polyrrhizae, Lemno-Utricularietum vulgaris, Potametum nodosi, Myriophyllo-Potametum and Najadetum marinae. In the studied vegetation, we also found an invasive phytocenosis Elodeetum canadensis that did not have an expanding tendency, and Ceratophyllo demersi-Vallisnerietum spiralis that had this tendency, which made monitoring its stands necessary. Physico-chemical analyses of water, conducted at localities in which the studied phytocenoses thrive, revealed that the development and distribution of most phytocenoses is closely linked with specific habitat conditions. Among the studied parameters, the most significant for the phytocenoses differentiation were: pH, alkalinity, COD-MnO4, BOD5, NO 3 ? , NO 2 ? , PO 4 3? and the concentration of total phosphorus.  相似文献   

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