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1.
An electrogenic biofilm was developed on a macroporous chitosan-carbon nanotube (CHIT-CNT) electrode under constant poised potential (?0.25 V versus Ag/AgCl reference electrode) and flow through conditions utilizing the effluent of an anaerobic digester as both the inoculant and substrate for the electrogenic biofilm. After 125 days of inoculation the bioelectrode demonstrated an open circuit potential of ?0.62 V and a current density of 9.43 μA cm?3 (at ?0.25 V). Scanning electron microscopy images indicate thorough surface coverage of the biofilm with a high density of bacterial nanowires physically connecting bacteria to bacteria and bacteria to carbon nanotube (electrode surface) suggesting the nanowires are electrically conductive. DGGE was used to identify the major bacterial and archaeal populations.  相似文献   

2.
As an emerging biotechnology capable of removing contaminants and producing electricity, microbial fuel cells (MFCs) hold a promising future in wastewater treatment. However, several main problems, including the high internal resistance (Rin), low power output, expensive material, and complicated configuration have severely hindered the large-scale application of MFCs. The study targeted these challenges by developing a novel MFC system, granular activated carbon single-chamber MFC, termed as GAC-SCMFC. The batch tests showed that GAC was a good substitute for carbon cloth and GAC-SCMFCs generated high and stable power outputs compared with the traditional two-chamber MFCs (2CMFCs). Critical operational parameters (i.e. wastewater substrate concentrations, GAC amount, electrode distance) affecting the performance of GAC-SCMFCs were examined at different levels. The results showed that the Rin gradually decreased from 60 Ω to 45 Ω and the power output increased from 0.2 W/m3 to 1.2 W/m3 when the substrate concentrations increased from 100 mg/L to 850 mg/L. However, at high concentrations of 1000–1500 mg/L, the power output leveled off. The Rin of MFCs decreased 50% when the electrode distance was reduced from 7.5 cm to 1 cm. The highest power was achieved at the electrode distance of 2 cm. The power generation increased with more GAC being added in MFCs due to the higher amount of biomass attached. Finally, the multi-anode GAC-SCMFCs were developed to effectively collect the electrons generated in the GAC bed. The results showed that the current was split among the multiple anodes, and the cathode was the limiting factor in the power production of GAC-SCMFCs.  相似文献   

3.
《Process Biochemistry》2014,49(10):1637-1646
One-pot conversion with whole cells of bacteria was performed for biooxidation of meso monocyclic (3a–b) and bicyclic diols (3c–e) into corresponding chiral lactones of bicyclo[4.3.0]nonane structure (2a–b) as well as exo- and endo-bridged lactones with the structure of [2.2.1] (3c–d) and [2.2.2] (3e). Micrococcus sp. DSM 30771 was selected as biocatalyst with significant alcohol dehydrogenase activity. Among tested strains, microbial oxidation of meso diols 3a–e catalyzed by Micrococcus sp. afforded enantiomerically pure ((+)-(2S,3R)-2c (ee = 99%), (+)-(2S,3R)-2e (ee = 99%)) or enriched ((+)-(1S,5R)-2a (ee = 90%), (−)-(1S,5R)-2b (ee = 86%), (+)-(2S,3R)-2d (ee = 80%)) lactone moieties. Comparative study with respect to microbial cultivation as well as biooxidation was undertaken to verify agreement of secondary metabolite biosynthesis in different scales: from MTP (4 mL), across shake flask (100 mL) till bioreactor (4 L). The results from biotransformations showed quite similar dependence in oxidation of all substrates 3a–e in MTP and flasks as well, thereby confirmed the validity and reasonable approach of using MTP for preliminary studies.  相似文献   

4.
《Small Ruminant Research》2009,85(1-3):41-46
Data on linear body measurements (LBM) of 403 sheep collected in three areas of KwaZulu-Natal were utilized to develop a prediction equation for live body weight of Zulu sheep. Data were collected on live weight (LW), heart girth (HG), wither height (WH) and scrotum circumference (SC) on sheep of all ages. The age of sheep was estimated by dentition. The analysis of variance showed that age and sex were important factors contributing to variation in LW of Zulu sheep. Phenotypic correlation coefficients and regression equations of LW on HG, WH and SC were computed within different age groups (milk set of teeth, one pair, two pairs and the three and four pairs of incisors). Low correlation coefficients (r = 0.21–0.48) between LW, HG and WH were found among the pregnant ewes. The relationship between LBM and LW was stronger (r = 0.66–0.86) for males than among females (r = 0.42–0.75). The cubic polynomial of HG was the best fit (R2 = 0.76) for the live weight prediction of young sheep with milk set of teeth. The combination of HG and WH produced the best fit for the two tooth and above males and non-pregnant females. The LW prediction equations for pregnant females were not reliable (R2 = 0.05–0.26). The SC was more precise (R2 = 0.61–0.80) when estimating the live weight of young males (<15–22-month-old) than of the older rams (R2 = 0.23–0.56). It was concluded that LW of Zulu sheep can be reasonably estimated using the HG and WH. A table could be constructed for the farmers to estimate the LW of their animals.  相似文献   

5.
Realizing the importance of forest carbon monitoring and reporting in climate change, the present study was conducted to derive spectrally modeled aboveground biomass and mitigation using Landsat data in combination with sampled field inventory data in the coniferous forests of Western Himalaya. After conducting preliminary survey in 2009, 90 quadrats (45 each for calibration and validation) of 0.1 ha were laid in six forest types for recording field inventory data viz. diameter at breast height, height, slope and aspect. Biomass carbon (Mg ha 1) was worked out for different forest types and crown density classes (open with 10–40% crown density and closed with > 40% crown density) using recommended volume equations, ratios and factors. Biomass carbon map (aboveground + belowground) was generated for the entire region using geospatial techniques. Normalized difference vegetation index (NDVI) was generated and spectral values were extracted to establish relation (R2 = 0.72, p < 0.01) with the field inventory data. The model developed was validated (R2 = 0.73, p < 0.01) with 45 sample observations not used earlier for predicting and generating biomass carbon map (2009) for the entire region. The data from field based inventory indicates highest total biomass carbon (171.40, σ ± 23.19) Mg ha 1 for Fir–Spruce (closed) which has relatively more mature girth classes and low tree density. This value was found to be significantly higher than other forest types. Lowest biomass carbon was observed for Blue Pine (open) (37.15, σ ± 11.82) Mg ha 1. The NDVI values for the entire region ranged from 0 to 0.62 and consequently the spectrally derived aboveground biomass carbon varied from 0 to 600 Mg ha 1. The study demonstrates the application of mapping, spectral responses and sampled field inventory for type wise assessment of carbon mitigation in temperate coniferous forests of Himalayas.  相似文献   

6.
We explored the relationships between surface-soil (1–20 cm) organic carbon isotopic signatures and associated climatic factors in central-east Asia in an attempt to develop transfer functions that can be used to retrieve the paleoclimatic information stored in the thick eolian–paleosol sequences within the area. Our analysis shows that the negative correlation between the surface-soil organic δ13C values and the mean annual precipitation is robust (R2 = 0.453; n = 196; p < 0.05) and the negative correlation with the growing-season (April–September) precipitation is more significant (R2 = 0.4966; n = 196; p < 0.05). Our study further shows that the positive correlation between the surface-soil organic δ13C values and mean growing-season aridity is most significant (R2 = 0.5805; n = 196; p < 0.05). We have smoothed both the organic δ13C values and the mean growing-season aridity values using a 3-point moving-window average-filter method in an attempt to remove some of random errors and found that the positive correlation between the two is further increased (R2 =  0.7784; n =  192; p < 0.05). These robust linear relationships demonstrate their value in reconstructing paleoclimate changes in the study area. The documented climatic dependency of the surface-soil carbon isotopic composition in the study area might have resulted both from the humidity-related isotopic enrichment processes of the dominant C3 plants (stomatal conductance and photosynthetic discrimination) and from the aridity-related abundance of C4 plants (mainly Chenopodiaceae species) along the S–N bioclimatic gradient.  相似文献   

7.
The present study evaluates the performance of air-cathode microbial fuel cells (MFCs) under alternating open circuit/closed circuit (OC/CC) modes and its effect on independent-electrode and full-cell potentials, power output (at different external resistances) and the polarization behaviour of the electrodes. Three different types of feeds were evaluated using this approach: (1) phosphorus buffer solution (PBS) with acetate as carbon source, (2) glucose-rich synthetic wastewater, and (3) sewage from wastewater treatment plant enriched with fermented molasses. When MFCs were suddenly switched to CC from OC and then again back to OC from CC, the behaviour of the anodes vs reference electrode (Ag/AgCl, 3 M KCl) was monitored. When electric circuit of the MFCs was switched from open to closed circuit, for all cases: (a) the anode potential-shift (vs Ag/AgCl) reallocated in the positive direction in about 200–400 mV, (b) the air-cathode potential-shift (vs Ag/AgCl) reallocated in the negative direction in about 10–25 mV, and (c) the cell-potential difference started at around 0 mV and progressively increased as the MFC reached stability. This behaviour was consistently reproduced during different OC/CC cycles. The systems studied delivered good performance with both controlled media and industrial wastewater. Additionally, this study provides insightful characterization of the independent-electrode behaviours.  相似文献   

8.
The purpose of the present study was to examine the patterns of responses for torque, electromyographic (EMG) amplitude, EMG mean power frequency (MPF), mechanomyographic (MMG) amplitude, and MMG MPF across 30 repeated maximal isometric (ISO) and concentric (CON) muscle actions of the leg extensors. Twelve female subjects (21.1 ± 1.4 yrs; 63.3 ± 7.4 kg) performed ISO and CON fatigue protocols with EMG and MMG signals recorded from the vastus lateralis. The relationships for torque, EMG amplitude, EMG MPF, MMG amplitude, and MMG MPF versus repetition number were examined using polynomial regression. The results indicated there were decreases (p < 0.05) across the ISO muscle actions for torque (r2 = 0.95), EMG amplitude (R2 = 0.44), EMG MPF (r2 = 0.62), and MMG MPF (r2 = 0.48), but no change in MMG amplitude (r2 = 0.07). In addition, there were decreases across the CON muscle actions for torque (R2 = 0.97), EMG amplitude (R2 = 0.46), EMG MPF (R2 = 0.86), MMG amplitude (R2 = 0.44), and MMG MPF (R2 = 0.80). Thus, the current findings suggested that the mechanisms of fatigue and motor control strategies used to modulate torque production were similar between maximal ISO and CON muscle actions.  相似文献   

9.
The cytotoxic activities of sesquilignans, (7S,8S,7′R,8′R)- and (7R,8R,7′S,8′S)-morinol A and (7S,8S,7′S,8′S)- and (7R,8R,7′R,8′R)-morinol B were compared, showing no significant difference between stereoisomers (IC50 = 24–35 μM). As a next stage, the effect of substituents at 7, 7′, and 7″-aromatic ring on the activity was evaluated to find out the higher activity of (7S,8S,7′R,8′R)-7,7′,7″-phenyl derivative 18 (IC50 = 6–7 μM). In the research on the structure–activity relationship of 7″-position of (7S,8S,7′R,8′R)-7,7′,7″-phenyl derivative 18, the most potent compounds were 7,7′,7″-phenyl derivative 18 (IC50 = 6 μM) against HeLa cells. Against HL-60 cells, 7″-(4-nitrophenyl)-7,7′-phenyl derivative 33 and 7″-hexyl-7,7′-phenyl derivative 37 (IC50 = 5 μM) showed highest activity. We discovered the compounds showed four to sevenfold potent activity than that of natural (7S,8S,7′R,8′R)-morinol A. It was also confirmed that the 7′-benzylic hydroxy group have an important role for exhibiting activity, on the other hand, the resonance system of cinnamyl structure is not crucial for the potent activity.  相似文献   

10.
The discovery and optimization of novel N-(3-(1,3-dioxo-2,3-dihydro-1H-pyrrolo[3,4-c]pyridin-4-yloxy)phenyl)benzenesulfonamide GPR119 agonists is described. Modification of the pyridylphthalimide motif of the molecule with R1 = –Me and R2 = iPr substituents, incorporated with a 6-fluoro substitution on the central phenyl ring offered a potent and metabolically stable tool compound 22.  相似文献   

11.
Agricultural intensification is altering biodiversity patterns worldwide. Rapid and effective methods are needed to monitor these changes in farmland biodiversity, but it becomes both a cost- and time-prohibitive task, particularly for hyper-diverse groups such as arthropods. We evaluated the effectiveness of surrogates in irrigated and rainfed wheat fields in a Mediterranean farmland in NW Spain in order to get a rapid tool to assess arthropod biodiversity. We studied six groups with different ecological needs (i.e. Aphididae, Aphidiinae, Coccinellidae, Formicidae, Heteroptera and Syrphidae) at species level (147 species), genus (105), family (10, only Heteroptera) and order (19) level. Higher taxa, cross-taxa and subset-taxa or total richness approaches were tested as well as the correlation in composition between levels for the selected groups, and the influence of farming regime. Genus richness was a good surrogate of species richness in all six groups studied (R2 = 0.38–0.60), like family and order were for Heteroptera (R2 = 0.37 and 0.29, respectively). Cross-taxa analyses showed that Aphididae and Aphidiinae genera (R2 = 0.19 and 0.30, respectively) and species (R2 = 0.20 and 0.28, respectively) were good surrogates for Aphidiinae and Aphididae species respectively. Coccinellidae genera (R2 = 0.26) and species (R2 = 0.25) were good surrogates for Heteroptera species. Finally, Aphididae and Coccinellidae both at genera (R2 = 0.14 and 0.20, respectively) and at species levels (R2 = 0.12–0.22, respectively) were good surrogates for total species richness of all groups. Genera composition was the best surrogate for the species composition within each group. Farming regime had no influence on the relationships between surrogates and species patterns in most cases. Our results suggest that genera level is a useful surrogate for all the studied groups and family is appropriate for Heteroptera. Genus level provided a saving of 15% of identification time in Aphididae and 80% for Coccinellidae. This proves its usefulness to asses and monitor biodiversity in wheat croplands and the possibility to reduce costs.  相似文献   

12.
The study investigated the suitability of stage of maturity and botanical fractions of whole crop rice (WCR) to predict yield and nutritive value of ensiled WCR for dairy cows. Eight varieties of WCR (i.e., Akichikara, Fukuhibiki, Habataki, Hamasari, Hokuriku 168, Kusanami, Tamakei 96, Yumetoiro) were harvested at four stages of maturity (i.e., 10, 22, 34, 45 days after flowering [DAF]) and ensiled. Dry matter (DM) yield at each harvest was determined. Silage samples were fractionated into four botanical fractions being: leaf blade, leaf sheath, stem and head. Silage samples were also analyzed for chemical composition, fermentation characteristics, in situ DM and N disappearance. Metabolizable energy (ME) and metabolizable protein (MP) content of samples were estimated according to Terada et al. (1988) and AFRC (1993), respectively. Relationships between maturity or proportions of botanical fractions and contents of WCR silage in terms of DM, ME and MP, and their yields, were estimated by correlation and regression analysis. Stage of maturity was positively related (P<0.001) to ME content (R2 = 0.46; y = 4.53 + 0.08X) and MP content (R2 = 0.56; y = 22.26 + 0.76X), and DM yield (R2 = 0.63; y = 9.21 + 0.12X), ME yield (R2 = 0.68, y = 36931 + 1708X) and MP yield (R2 = 0.72, y = 161.0 + 14.15X) of WCR. Proportion of leaf was negatively related to yields and nutritive value of ensiled WCR, whilst proportion of head was positively related (P<0.05 to <0.001). Proportion of head was best related to the ME content (R2 = 0.72; y = 3.26 + 0.009X), MP content (R2 = 0.72; y = 12.31 + 0.079X), and DM yield (R2 = 0.41; y = 9.02 + 0.009X), ME yield (R2 = 0.76, y = 19494 + 165.5X), and MP yield (R2 = 0.75, y = 34.37 + 1.32X) of WCR. Results suggest that to optimize yield and nutritive value, WCR should be ensiled within 40 DAF and the proportion of head should be equal to or more than 500 g per kg DM of WCR silage. Stage of maturity and proportion of head of WCR predict yields of DM, ME and MP of WCR, and their contents, in WCR silage with acceptable accuracy. However, these relationships need to be validated using large data sets and in vivo studies.  相似文献   

13.
A DC/DC booster circuit was fabricated and tested for use with microbial fuel cells (MFCs) to increase the typical operational voltage (100–300 mV) to a maximum power of >3 V. In steady state, the low power DC/DC voltage booster circuit was sustainable, i.e., powered by the MFCs alone, but required an external power source to start (but not needed to maintain) the oscillator. The operating principle and function of each part of the circuit is described. A procedure for determining the optimal set of values for each component in the circuit was established. The performance of the circuit was demonstrated using three Shewanella oneidensis MR-1 based MFCs connected in parallel. The power consumption of the booster circuit was less than 20 μW, which was less than the output from the three MFCs. After the output capacitor was charged to 5 V, the booster circuit can be powered by the MFCs alone. Under normal operation, the MFCs were able to power the booster circuit and a light emitting diode.  相似文献   

14.
Water transparency is one of the ecological indicators for describing water quality and the underwater light field which determines its productivity. In the European Water Framework Directive (WFD) as well as in the European Marine Strategy Framework Directive (MSFD) water transparency is used for ecological status classification of inland, coastal and open sea waters and it is regarded as an indicator for eutrophication in Baltic Sea management (HELCOM, 2007). We developed and compared different empirical and semi-analytical algorithms for lakes and coastal Nordic waters to retrieve Secchi depth (ZSD) from remote sensing data (MERIS, 300 m resolution). The algorithms were developed in water bodies with high coloured dissolved organic matter absorption (aCDOM(442) ranging 1.7–4.0 m−1), Chl a concentration (0.5–73 mg m−3) and total suspended matter (0.7–37.5 g m−3) and validated against an independent data set over inland and coastal waters (0.6 m < ZSD < 14.8 m). The results indicate that for empirical algorithms, using longer wavelengths in the visible spectrum as a reference band decreases the RMSE and increases the coefficient of determination (R2). The accuracy increased (R2 = 0.75, RMSE = 1.33 m, n = 134) when ZSD was retrieved via an empirical relationship between ZSD and Kd(490). The best agreement with in situ data was attained when ZSD was calculated via both the diffuse and the beam attenuation coefficient (R2 = 0.89, RMSE = 0.77 m, n = 89). The results demonstrate that transparency can be retrieved with high accuracy over various optical water types by the means of ocean color remote sensing, improving both the spatial and temporal coverage. The satellite derived ZSD product could be therefore used as an additional source of information for WFD and MSFD reporting purposes.  相似文献   

15.
The higher counts or particular groups (Firmicutes/Bacteroidetes) of intestinal microbiota are related to host metabolic reactions, supporting a balance of human ecosystem. We further explored whether intestinal lactobacilli were associated with some principal cellular and metabolic markers of blood in 38 healthy >65-year-old persons. The questionnaire, routine clinical and laboratory data of blood indices as much as the oxidized low-density lipoprotein (ox-LDL) and baseline diene conjugates in low-density lipoprotein (BDC-LDL) of blood sera were explored. The PCR-based intestinal Lactobacillus sp. composition and counts of cultivable lactobacilli (LAB) were tested. The facultative heterofermentative lactobacilli (Lactobacillus casei and Lactobacillus paracasei) were the most frequent (89 and 97%, respectively) species found, while Lactobacillus acidophilus, Lactobacillus plantarum and Lactobacillus reuteri were present in almost half of the elderly persons. The number of species simultaneously colonizing the individuals ranged from 1 to 7 (median 4). In elderly consuming probiotics the LAB counts were significantly higher than in these not consuming (median 7.8, range 4.2–10.8 vs. median 6.3, range 3.3–9.7 log cfu/g; p = 0.005), adjusted (OR = 1.71, CI95 1.04–2.82; p = 0.035) for age and body mass index (BMI). The colonization by L. acidophilus was negatively related (r = ?0.367, p = 0.0275) to L. reuteri, staying significant after adjusting for age, sex and BMI (OR = 0.16, CI95 0.04–0.73; p = 0.018). However, the blood glucose concentration showed a tendency for a negative correlation for colonization with Lactobacillus fermentum (r = ?0.309, p = 0.062) adjusted for BMI (Adj. R2 = 0.181; p = 0.013) but not for age and sex. The higher white blood cells (WBC) count was positively related (r = 0.434, p = 0.007) to presence of Lactobacillus reuteri adjusted for age, sex and BMI (Adj. R2 = 0.193, p = 0.027). The lower values of ox-LDL were predicted by higher counts of cultivable lactobacilli adjusted by sex, age and BMI (r = ?0.389, p = 0.016; Adj. R2 = 0.184 p = 0.029). In conclusion, the pilot study of elderly persons shows that the intestinal lactobacilli are tightly associated with WBC count, blood glucose and content of ox-LDL which all serve as risk markers in pathogenesis of inflammation, metabolic syndrome and cardiovascular disease (CVD).  相似文献   

16.
A novel series of formoterol–phthalazinone hybrids were synthesised and evaluated as dual pharmacology β2-adrenoceptor agonists and PDE4 inhibitors. Most of the hybrids displayed high β2-adrenoceptor agonist and moderate PDE4 inhibitory activities. The most potent compound, (R,R)-11c, exhibited agonist (EC50 = 1.05 nM, pEC50 = 9.0) and potent PDE4B2 inhibitory activities (IC50 = 0.092 μM).  相似文献   

17.
All stereoisomers of methoxybutane and fluorobutane type of 1,7-seco-2,7′-cyclolignane were synthesized and cytotoxic activities of these compounds were compared with those of all stereoisomers of butane and butanol type compounds. Both enantiomers of butane type secocyclolignane showed higher cytotoxic activity (IC50 = 16–20 μM) than methoxy type compounds, whereas none was observed for all the stereoisomers of butanol type secocyclolignane, however, (−)-Kadangustin J showed stereospecific cytotoxic activity (IC50 = 47–67 μM). Since (R)-9′-fluoro derivative 23 was most potent (IC50 = 19 μM) among the corresponding fluoro stereoisomers, (R)-9′-alkyl derivatives were synthesized, hydrophobic 9′-heptyl derivative 27 showing highest activity (IC50 = 3.7 μM against HL-60, IC50 = 3.1 μM against HeLa) in this experiment. Apoptosis induction caused by Caspase 3 and 9 for (R)-9′-heptyl derivative 27 was observed in the research on the mechanism. A degradation of DNA into small fragments was also shown by DNA ladder assay.  相似文献   

18.
《Inorganica chimica acta》2006,359(11):3549-3556
A series of cationic trispyrazolylmethane complexes of the general form [TmRM(CH3CN)3]2+ (Tm = tris(pyrazolyl)methane, 1, R = 3,5-Me2, M = Fe(II); 2, R = 3-Ph, M = Fe(II); 3, R = 3,5-Me2, M = Co(II); 4, R = 3-Ph, M = Co(II)) with ‘piano-stool’ structures was prepared by the reaction of the N3tripodal ligands (TmR)with [(CH3CN)6M](BF4)2 in a 1:1 stoichiometric ratio. Magnetic susceptibility measurements indicate that all four complexes with BF4 counter anions are paramagnetic, high-spin systems in the solid state with μeff at high temperatures of 5.2 (1, S = 2), 5.4 (2, S = 2), 4.9 (3, S = 3/2) and 4.6 (4, S = 3/2) BM, respectively. Comparisons of bond lengths from the metal centre to the TmR nitrogen donors, and from the metal centre to the acetonitrile nitrogen donors indicate that the neutral tripodal ligands appear to be more weakly coordinated to the metal centre than are the acetonitrile ligands. Reactions of these tripodal complexes with bidentate phosphine ligands, such as 1,2-diphosphinoethane or 1,2-bis(diallylphosphino)ethane leads to displacement of the tripodal ligand, or to the formation of more thermally stable bis-ligand complexes M(TmR)2 (R = 3,5-dimethyl).  相似文献   

19.
ObjectiveTo analyze the relationship of genetic polymorphisms in IL1β, IL6, TNF-α genes and their receptors genes with rheumatoid arthritis (RA) for northwest Han Chinese. This study also explores whether there are gene–gene interactions among these genetic polymorphisms.MethodsA total of 452 patients with RA and 373 matched healthy controls were enrolled to carry out a case-control study for 16 SNPs of IL1B-511 C > T, IL1B-31 T > C, IL1B+3954 C > T, IL1RN T > C, IL6-597 G > A, IL6-572 G > C, IL6-174 G > C, IL6R-183 G > A, IL6R exon2 T > A, IL6R exon1 A > C, TNFA-863 C > A, TNFA-857 C > T, TNFA-308 G > A, TNFA-238 G > A, TNFR1-383 A > C and TNFR2 T676G T > G from seven genes. Genotyping for the SNPs was conducted on the RotorGene 6000 PCR platform using in-house high resolution melting (HRM) approaches. Detection correctness was validated through direct sequencing. Generalized multifactor dimensionality reduction (GMDR) analysis was applied to discover likely gene–gene interaction model among the SNPs.ResultsThe results showed that the genotype distributions of TNFA-308, TNFA-857 and TNFA-863 are significantly different between case and control groups (P = 0.016, P = 0.048 and P = 0.016, respectively). Carriers of TNFA-857 mutant allele conferred risk to RA (OR = 1.525, 95% CI = 1.157–2.009) while those of TNFA-308 and TNFA-863 mutant alleles conferred protection to RA (OR = 0.459, 95% CI = 0.286–0.739; OR = 0.490, 95% CI = 0.329–0.732). GMDR analysis for the SNPs indicated that gene–gene interaction existed among IL1B-31, IL1RN, IL6-572, IL6R-183, IL6R-exon1 and TNFA-857. Thirteen of all genotypes of the six SNPs combination were discovered to have significant distribution difference between RA group and the control.ConclusionsThis study demonstrated that PCR-HRM assay is a highly efficient SNP genotyping method especially for the detection of large-scale samples. The SNPs of TNFA-308 and TNFA-863 are closely associated with RA susceptibility and that gene–gene interactions may occur among the six SNPs of IL1B-31, IL1RN, IL6-572, IL6R-183, IL6R-exon1 and TNFA-857 in RA patients from northwest Chinese Han population, especially these SNPs’ combination genotypes CT/TT/CC/GG/AC/CC, CT/TT/GC/AA/AC/CT and CT/CT/CC/GA/AC/CC to show high risk of RA susceptibility in our study.  相似文献   

20.
PurposeAngiogenesis, a multistep process that results in new blood vessel formation from preexisting vasculature is essential for both the growth of solid tumour and for metastasis. Stimulation of vascular endothelial growth factor receptor (VEGFR), a transmembrane glycoprotein, results in mitogenesis. Within this family of receptors, VEGFR 2/kinase-insert-domain containing receptor appears to be principally upregulated during tumorigenesis. The aim of this study was to determine the expression of VEGFR-2/kinase-insert-domain containing receptor (KDR) and its correlation with angiotensin receptor type 1 (AT1-R) and clinical factors in endometrial carcinoma.MethodsThe expression of KDR and AT1-R was studied in endometrial carcinoma and normal endometrium by Real-time RT-PCR and Western blot analysis in 136 samples. The expression profile was correlated with the clinicopathological characteristics of endometrial adenocarcinoma.ResultsWe noted a significant correlation between the expression of KDR and AT1-R in tumour grade G1, G2 and G3 (Rs = 0.50; p = 0.002, Rs = 0.69; p = 0.0001, Rs = 0.52; p = 0.005, respectively). In stage I and stage II carcinoma, a significant correlation was also found between the expression of KDR and AT1-R (Rs = 0.70, p = 0.0001, Rs = 0.67; p = 0.001, respectively). Moreover significant correlation was observed between both KDR and AT1-R in tissue with different myometrial invasion (Rs = 0.54, p = 0.0001, Rs = 0.68; p = 0.0001; respectively for tumours with invasion into the inner half and invasion into the outer half).ConclusionsBasing on received correlation between AT1-R and KDR expression and previous results we speculate that angiotensin through AT1-R modulates KDR expression and thus have influence on local VEGF level. However, further studies are required to clarify the biological interaction between KDR, AT1-R and other hormonal regulators in endometrial carcinoma.  相似文献   

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