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1.
2.
Using PCR-SSCP with five primer pairs, we detected six single nucleotide polymorphisms of the H-FABP gene: 332G → A, 534G → A, 783C → T, 835C → T, 1198T → C, and 2329C → T. Chi-square results showed significant differences (P < 0.05) in genotype frequency among breeds in Fragment 1 and extremely significant differences (P < 0.01) in Fragments 2–4. We found a significant association between Fragment 2 genotype and muscle fiber number, Arg and Thr (P < 0.05); between Fragment 3 genotype and living weight, carcass weight, breast muscle weight, abdominal fat weight, and abdominal fat percentage (P < 0.05); between Fragment 4 genotype and Thr, Phe, and inosinic acid (P < 0.05). It was concluded that H-FABP was the major gene influencing slaughter performance and meat quality or was linked with the major gene in these strains and that the C783T mutation could be used as a candidate molecular genetic marker for breeding selection. The combination M1C2–B2B2–D1D1 is an ideal model for breeding in these strains because it can improve slaughter and meat quality traits.  相似文献   

3.
With the intent to identify informative predictors of myocardial infarction (MI) development in an ethnically homogenous group of Russian men after MI (255 subjects) and in a corresponding control group (257 subjects), an analysis of genotype frequency distribution for polymorphic DNA markers (SNP) rs16944 (?511C>T, IL1B gene), rs1800796 (?572G>C, IL6 gene), rs1800872 (?592C>A, IL10 gene), rs3212227 (1159A>C, IL12B gene), rs1800629 (?308G>A, TNF), rs909253 (252A>G, LTA), rs767455 (36A>G, TNFRSF1A) was conducted. Using the Monte Carlo method and a Markov chain (APSampler), allele combinations associated both with decreased and increased MI risk were revealed. The most significant results were obtained for IL6*C/C (P = 3 × 10?4, OR = 6.3 CI 2.37–16.75), LTA*A + IL6*G/G (FDR = 2.3 × 10?4, OR = 0.25 CI 0.14–0.46), LTA*G/G + IL12B*A/A (FDR = 0.0053, OR = 4.92 CI 1.8–13.33), TNF*G + LTA*G/G + TNFRSF1A*A (FDR = 0.013, OR = 4.38, CI 1.6–12.01), TNFRSF1A*G + IL10*A/A + IL12B*C (FDR = 0.016, OR = 8.79, CI 2.17–35.63), TNF*G + LTA*G/G + IL10*C (FDR = 0.0105, OR = 3.54 CI 1.55–8.09).  相似文献   

4.
Beta-thalassemia is the most frequent hereditary blood disorder in Tunisia because of its geographic localization and history. This pathology is characterized by a complex multisystem process with genetic and biochemical interactions. The aim of this work was to establish phenotype/genotype association through studying the distribution and the relationship between β-thalassemia and α-thalassemia mutations and three polymorphic markers: the C → T polymorphism at ?158 of the Gγ gene, the RFLP haplotype and the repeated sequence (AT)xTy in the β globin silencer, in two groups of β-thalassemia major and β-thalassemia intermedia (TI) patients. Statistical analysis has shown that moderate expression seen in TI patients was significantly associated to β+ ?87 (C → G), ?30 (T → A) and IVSI-6 (T → C) mutations, haplotypes VIII, IX and Nb and to XmnI polymorphism. The regression analysis of combined genotypes (mutation/XmnI/RFLP haplotype) revealed that they contribute to justify 17.1 % of clinical expression diversity (p < 0.05). Among the studied genotypes the XmnI polymorphism seems to be the most determinant modulating factor, followed by the β-thalassemia mutation and RFLP haplotype. Our findings highlight the heterogeneity of molecular background of β-thalassemia that would be responsible of clinical variability.  相似文献   

5.
The anion–π interactions between Br, Cl, F and H anions and hexafluorobenzene (HFB), 1,2,4,5-tetracyanobenzene (TCB) and tetracyanopyrazine (TCP) have been studied by standard and counterpoise (CP) corrected methods at HF, B3LYP and MP2/6-31+ + G (d,p) levels of theory. The complexation energies were corrected for basis set superposition error (ΔE BSSE) and zero point energy (ΔE BSSE + ZPE). Also, the B3LYP results were corrected by single-point calculation at B3LYP/aug-cc-PVTZ level of theory. Although the CP-corrected method results in higher distances between anions and rings, the standard method gives lower complexation energies. TCP…X series gives higher complexation energies in both CP-corrected and standard methods. Topological analysis of the charge density ρ(r) has been performed by the means of atoms in molecules method on the wave functions obtained at MP2/6-31+ + G (d,p) level of theory. The number and the nature of critical points depend on aromatic ring and anion. Natural bond orbital analysis indicates that nX → π*CC and nX → π*CN interactions are the most important interactions for TCB (and HFB)…X and TCP…X complexes, respectively.  相似文献   

6.
A membrane fraction from etiolated 6-day-old primary radish roots (Raphanus sativus L. var hortensis) contained β-glucuronosyltransferases (GlcATs) involved in the synthesis of the carbohydrate moieties of arabinogalactan proteins (AGPs). The GlcATs transferred [14C]GlcA from UDP-[14C]GlcA on to β-(1 → 3)-galactan as an exogenous acceptor substrate, giving a specific activity of 50–150 pmol min?1 (mg protein)?1. The enzyme specimen also catalyzed the transfer of [14C]GlcA on to an enzymatically modified AGP from mature radish root. Analysis of the transfer products revealed that the transfer of [14C]GlcA occurred preferentially on to consecutive (1 → 3)-linked β-Gal chains as well as single branched β-(1 → 6)-Gal residues through β-(1 → 6) linkages, producing branched acidic side chains. The enzymes also transferred [14C]GlcA residues on to several oligosaccharides, such as β-(1 → 6)- and β-(1 → 3)-galactotrioses. A trisaccharide, α-l-Araf-(1 → 3)-β-Gal-(1 → 6)-Gal, was a good acceptor, yielding a branched tetrasaccharide, α-l-Araf-(1 → 3)[β-GlcA-(1 → 6)]-β-Gal-(1 → 6)-Gal. We report the first in vitro assay system for β-GlcATs involved in the AG synthesis as a step toward full characterization and cloning.  相似文献   

7.
This study provides the first accurate investigation of the tautomerization of the biologically important guanine*·thymine (G*·T) DNA base mispair with Watson–Crick geometry, involving the enol mutagenic tautomer of the G and the keto tautomer of the T, into the G·T* mispair (?G?=?.99?kcal?mol?1, population?=?15.8% obtained at the MP2 level of quantum-mechanical theory in the continuum with ε?=?4), formed by the keto tautomer of the G and the enol mutagenic tautomer of the T base, using DFT and MP2 methods in vacuum and in the weakly polar medium (ε?=?4), characteristic for the hydrophobic interfaces of specific protein–nucleic acid interactions. We were first able to show that the G*·T?G·T* tautomerization occurs through the asynchronous concerted double proton transfer along two antiparallel O6H···O4 and N1···HN3 H-bonds and is assisted by the third N2H···O2 H-bond, that exists along the entire reaction pathway. The obtained results indicate that the G·T* base mispair is stable from the thermodynamic point of view complex, while it is dynamically unstable structure in vacuum and dynamically stable structure in the continuum with ε?=?4 with lifetime of 6.4·10?12?s, that, on the one side, makes it possible to develop all six low-frequency intermolecular vibrations, but, on the other side, it is by three orders less than the time (several ns) required for the replication machinery to forcibly dissociate a base pair into the monomers during DNA replication. One of the more significant findings to emerge from this study is that the short-lived G·T* base mispair, which electronic interaction energy between the bases (?23.76?kcal?mol?1) exceeds the analogical value for the G·C Watson–Crick nucleobase pair (?20.38?kcal?mol?1), “escapes from the hands” of the DNA replication machinery by fast transforming into the G*·T mismatch playing an indirect role of its supplier during the DNA replication. So, exactly the G*·T mismatch was established to play the crucial role in the spontaneous point mutagenesis.  相似文献   

8.
The transfer of carbon (C) from Amazon forests to aquatic ecosystems as CO2 supersaturated in groundwater that outgases to the atmosphere after it reaches small streams has been postulated to be an important component of terrestrial ecosystem C budgets. We measured C losses as soil respiration and methane (CH4) flux, direct CO2 and CH4 fluxes from the stream surface and fluvial export of dissolved inorganic C (DIC), dissolved organic C (DOC), and particulate C over an annual hydrologic cycle from a 1,319-ha forested Amazon perennial first-order headwater watershed at Tanguro Ranch in the southern Amazon state of Mato Grosso. Stream pCO2 concentrations ranged from 6,491 to 14,976 ??atm and directly-measured stream CO2 outgassing flux was 5,994 ± 677 g C m?2 y?1 of stream surface. Stream pCH4 concentrations ranged from 291 to 438 ??atm and measured stream CH4 outgassing flux was 987 ± 221 g C m?2 y?1. Despite high flux rates from the stream surface, the small area of stream itself (970 m2, or 0.007% of watershed area) led to small directly-measured annual fluxes of CO2 (0.44 ± 0.05 g C m2 y?1) and CH4 (0.07 ± 0.02 g C m2 y?1) per unit watershed land area. Measured fluvial export of DIC (0.78 ± 0.04 g C m?2 y?1), DOC (0.16 ± 0.03 g C m?2 y?1) and coarse plus fine particulate C (0.001 ± 0.001 g C m?2 y?1) per unit watershed land area were also small. However, stream discharge accounted for only 12% of the modeled annual watershed water output because deep groundwater flows dominated total runoff from the watershed. When C in this bypassing groundwater was included, total watershed export was 10.83 g C m?2 y?1 as CO2 outgassing, 11.29 g C m?2 y?1 as fluvial DIC and 0.64 g C m?2 y?1 as fluvial DOC. Outgassing fluxes were somewhat lower than the 40?C50 g C m?2 y?1 reported from other Amazon watersheds and may result in part from lower annual rainfall at Tanguro. Total stream-associated gaseous C losses were two orders of magnitude less than soil respiration (696 ± 147 g C m?2 y?1), but total losses of C transported by water comprised up to about 20% of the ± 150 g C m?2 (±1.5 Mg C ha?1) that is exchanged annually across Amazon tropical forest canopies.  相似文献   

9.
Increasing interest in cytochrome P450 2B6 (CYP2B6) genetic polymorphism was stimulated by revelations of a specific CYP2B6 genotype significantly affecting the metabolism of various drugs in common clinical use in terms of increasing drug efficacy and avoiding adverse drug reactions. The present study aimed to determine the frequencies of CYP2B6*4 CYP2B6*5, CYP2B6*6, CYP2B6*7 and CYP2B6*9 alleles in healthy Turkish individuals (n = 172). Frequencies of three single nucleotide polymorphisms were 516G>T (28 %), 785A>G (33 %), and 1459C>T (12 %). The frequencies of CYP2B6*1, *4, *5, *6, *7, and *9 alleles were 54.3 (95 % CI 49.04–59.56), 6.4 % (95 % CI 3.81–8.99), 11 % (95 % CI 7.69–14.31), 25.3 % (95 % CI 20.71–29.89), 0.87 % (95 % CI ?0.11–1.85) and 2.0 % (95 % CI 0.52–3.48), respectively. Allele *6 was more frequent (25.3 %) than the other variant alleles in Turkish subjects. The frequencies of CYP2B6*4, *5, *6, *7, and *9 alleles were similar to European populations but significantly different from that reported for Asian populations. This is the first study to document the frequencies of the CYP2B6*4, *5, *6, *7, *9 alleles in the healthy Turkish individuals and our results could provide clinically useful information on drug metabolism by CYP2B6 in Turkish population.  相似文献   

10.
Old-growth forests are important stores for carbon as they may accumulate C for centuries. The alteration of biomass and soil carbon pools across the development stages of a forest dynamics cycle has rarely been quantified. We studied the above- and belowground C stocks in the five forest development stages (regeneration to decay stage) of a montane spruce (Picea abies) forest of the northern German Harz Mountains, one of Central Europe’s few forests where the natural forest dynamics have not been disturbed by man for several centuries. The over-mature and decay stages had the largest total (up to 480 Mg C ha?1) and aboveground biomass carbon pools (200 Mg C ha?1) with biomass C stored in dead wood in the decay stage. The soil C pool (220–275 Mg C ha?1, 0–60 cm) was two to three times larger than in temperate lowland spruce forests and remained invariant across the forest dynamics cycle. On the landscape level, taking into account the frequency of the five forest development stages, the total carbon pool was approximately 420 Mg C ha?1. The results evidence the high significance of over-mature and decaying stages of temperate mountain forests not only for conserving specialized forest organisms but also for their large carbon storage potential.  相似文献   

11.
Melanocortin 4 receptor (MC4R) plays a crucial part in regulating feeding behavior in humans and rodents. We detected two single nucleotide polymorphisms (SNPs; c.108G → A and c.627C → T) in the goose MC4R gene and genotyped 94 Landes geese for association analysis with several carcass traits. Significant associations (P < 0.05) were obtained for c.108G → A with carcass weight, breast muscle percentage, and leg muscle percentage, and for c.627C → T with body weight, carcass weight, semi-eviscerated weight, and eviscerated weight. We re-constructed haplotypes based on the two SNPs and analyzed diplotypes in association with carcass traits, obtaining significant associations with several of the traits. These results suggest that polymorphisms in the MC4R gene could have effects on carcass traits in Landes geese. More study is required to confirm these results.  相似文献   

12.
Epidemiological genetics established that heritability in determining the risk of myocardial infarction (MI) is substantially greater when MI occurs early in life. However, the genetic architecture of early-onset and late-onset MI was not compared. We analyzed genotype frequencies of SNPs in/near 20 genes whose protein products are involved in the pathogenesis of atherosclerosis in two groups of Russian patients with MI: the first group included patients with age of first MI onset <60 years (N?=?230) and the second group with onset ≥60 years (N?=?174). The control group of corresponding ethnicity consisted of 193 unrelated volunteers without cardiovascular diseases (93 individuals were over 60 years). We found that in the group of patients with age of onset <60 years, SNPs FGB rs1800788*T, TGFB1 rs1982073*T/T, ENOS rs2070744*C and CRP rs1130864*T/T were associated with risk of MI, whereas in patients with age of onset ≥60 years, only TGFB1 rs1982073*T/T was associated with risk of MI. Using APSampler software, we found composite markers associated with MI only in patients with early onset: FGB rs1800788*T?+?TGFB1 rs1982073*T; FGB rs1800788*T?+?LPL rs328*C?+?IL4 rs2243250*C; FGB rs1800788*T?+?ENOS rs2070744*C (Fisher p values of 1.4?×?10?6 to 2.2?×?10?5; the permutation p values of 1.1?×?10?5 to 3.0?×?10?4; ORs?=?2.67–2.54). Alleles included in the combinations were associated with MI less significantly and with lower ORs than the combinations themselves. The result showed a substantially greater contribution of the genetic component in the development of MI if it occurs early in life, and demonstrated the usefulness of genetic testing for young people.  相似文献   

13.
The amounts, sources and relative ages of inorganic and organic carbon pools were assessed in eight headwater streams draining watersheds dominated by either forest, pasture, cropland or urban development in the lower Chesapeake Bay region (Virginia, USA). Streams were sampled at baseflow conditions six different times over 1 year. The sources and ages of the carbon pools were characterized by isotopic (δ13C and ?14C) analyses and excitation emission matrix fluorescence with parallel factor analysis (EEM–PARAFAC). The findings from this study showed that human land use may alter aquatic carbon cycling in three primary ways. First, human land use affects the sources and ages of DIC by controlling different rates of weathering and erosion. Relative to dissolved inorganic carbon (DIC) in forested streams which originated primarily from respiration of young, 14C-enriched organic matter (OM; δ13C = ?22.2 ± 3 ‰; ?14C = 69 ± 14 ‰), DIC in urbanized streams was influenced more by sedimentary carbonate weathering (δ13C = ?12.4 ± 1 ‰; ?14C = ?270 ± 37 ‰) and one of pasture streams showed a greater influence from young soil carbonates (δ13C = ?5.7 ± 2.5 ‰; ?14C = 69 ‰). Second, human land use alters the proportions of terrestrial versus autochthonous/microbial sources of stream water OM. Fluorescence properties of dissolved OM (DOM) and the C:N of particulate OM (POM) suggested that streams draining human-altered watersheds contained greater relative contributions of DOM and POM from autochthonous/microbial sources than forested streams. Third, human land uses can mobilize geologically aged inorganic carbon and enable its participation in contemporary carbon cycling. Aged DOM (?14C = ?248 to ?202 ‰, equivalent14C ages of 1,811–2,284 years BP) and POM (?14C = ?90 to ?88 ‰, 14C ages of 669–887 years BP) were observed exclusively in urbanized streams, presumably a result of autotrophic fixation of aged DIC (?297 to ?244 ‰, 14C age = 2,251–2,833 years BP) from sedimentary shell dissolution and perhaps also watershed export of fossil fuel carbon. This study demonstrates that human land use may have significant impacts on the amounts, sources, ages and cycling of carbon in headwater streams and their associated watersheds.  相似文献   

14.
Dendrocalamus sinicus, which is the largest bamboo species in the world, has broad prospects in the fields of bioenergy and biorefinery application. In this study, dewaxed D. sinicus samples were sequentially treated with 80 % ethanol containing 0.025 M HCl, 80 % ethanol containing 0.5 % NaOH, and aqueous alkaline solutions (containing 2.0, 5.0, and 8.0 % NaOH, respectively) at 75 °C for 4 h, in which 9.63, 8.71, 21.83, 21.09, and 13.09 % of the original lignin were isolated, respectively. The lignin fractions obtained were comparatively characterized by chemical composition, molecular weights, and structural features by wet chemical and instrumental analysis methods. It was found that the bamboo lignin fractions isolated by ethanol had lower weight-average molecular weights (1,360–1,380 g?mol?1) and contained much higher amounts of associated hemicelluloses, while the lignin fractions isolated by aqueous alkaline solutions had higher weight-average molecular weights (5,300–6,040 g?mol?1) and contained lower amounts of associated hemicelluloses. Spectroscopy analyses indicated that the bamboo lignin was a typical grass lignin, consisting of p-hydroxyphenyl (H), guaiacyl (G), and syringyl (S) units. A small percentage of the lignin side-chain was found to be acetylated at the γ-carbon, predominantly at syringyl units. The major interunit linkages present in the bamboo lignin obtained were β-O-4′ aryl ether linkages, together with lower amounts of β-β′, β-5′, and β-1′ linkages.  相似文献   

15.
Coarse woody debris (CWD) is an important component of the forest carbon cycle, acting as a carbon pool and a source of CO2 in temperate forest ecosystems. We used a soda-lime closed-chamber method to measure CO2 efflux from downed CWD (diameter ≥5 cm) and to examine CWD respiration (R CWD) under field conditions over 1 year in a temperate secondary pioneer forest in Takayama forest. We also investigated tree mortality (input to the CWD pool) from the data obtained from the annual tree census, which commenced in 2000. We developed an exponential function of temperature to predict R CWD in each decay class (R 2 = 0.81–0.97). The sensitivity of R CWD to changing temperature, expressed as Q 10, ranged from 2.12 to 2.92 and was relatively high in decay class III. Annual C flux from CWD (F CWD) was extrapolated using continuous air temperature measurements and CWD necromass pools in the three decay classes. F CWD was 3.0 (class I), 17.8 (class II), and 13.7 g C m?2 year?1 (class III) and totaled 34 g C m?2 year?1 in 2009. Annual input to CWD averaged 77 g C m?2 year?1 from 2000 to 2009. The budget of the CWD pool in the Takayama forest, including tree mortality inputs and respiratory outputs, was 0.43 Mg C ha?1 year?1 (net C sink) owing to high tree mortality in the mature pioneer forest. The potential CWD sink is important for the carbon cycle in temperate successional forests.  相似文献   

16.
Biometric-based carbon flux measurements were conducted in a pine forest on lava flow of Mt. Fuji, Japan, in order to estimate carbon cycling and sequestration. The forest consists mainly of Japanese red pine (Pinus densiflora) in a canopy layer and Japanese holly (Ilex pedunculosa) in a subtree layer. The lava remains exposed on the ground surface, and the soil on the lava flow is still immature with no mineral soil layer. The results showed that the net primary production (NPP) of the forest was 7.3 ± 0.7 t C ha?1 year?1, of which 1.4 ± 0.4 t C ha?1 year?1 was partitioned to biomass increment, 3.2 ± 0.5 t C ha?1 year?1 to above-ground fine litter production, 1.9 t C ha?1 year?1 to fine root production, and 0.8 ± 0.2 t C ha?1 year?1 to coarse woody debris. The total amount of annual soil surface CO2 efflux was estimated as 6.1 ± 2.9 t C ha?1 year?1, using a closed chamber method. The estimated decomposition rate of soil organic matter, which subtracted annual root respiration from soil respiration, was 4.2 ± 3.1 t C ha?1 year?1. Biometric-based net ecosystem production (NEP) in the pine forest was estimated at 2.9 ± 3.2 t C ha?1 year?1, with high uncertainty due mainly to the model estimation error of annual soil respiration and root respiration. The sequestered carbon being allocated in roughly equal amounts to living biomass (1.4 t C ha?1 year?1) and the non-living C pool (1.5 t C ha?1 year?1). Our estimate of biometric-based NEP was 25 % lower than the eddy covariance-based NEP in this pine forest, due partly to the underestimation of NPP and difficulty of estimation of soil and root respiration in the pine forest on lava flows that have large heterogeneity of soil depth. However, our results indicate that the mature pine forest acted as a significant carbon sink even when established on lava flow with low nutrient content in immature soils, and that sequestration strength, both in biomass and in soil organic matter, is large.  相似文献   

17.
Respiration and calcification rate were estimated to quantify the effect of Zhikong scallop Chlamys farreri on marine CO2 system in Sanggou Bay, China. The C. farreri population in Sanggou Bay sequestered 78.06?±?5.76 g C m?2 y?1 for shell formation, while the CO2 fluxes due to calcification and respiration were 53.95?±?3.98 and 71.69?±?6.51 g C m?2 y?1, respectively. In order to eliminate the additional CO2 released from calcification and respiration process of C. farreri, Gracilaria lemaneiformis were introduced into the integrated system and its role was validated by in situ mesocosm methods. Eight mesocosms (1,000 L) were deployed over 42-h period and consisted of four treatments: seaweed-only, scallop-only (SP), seaweed integrated with scallop (SS), and control (C). The aqueous CO2 concentration and partial pressure of CO2 in SP treatments were significantly higher than the other three treatments (p?<?0.01), while there were no difference between SS treatments and C treatments (p?>?0.05). Furthermore, compared with the SP treatments, the presence of the G. lemaneiformis can keep the seawater pH stable. These findings suggest that seaweed and shellfish integrated aquaculture practice cannot only reduce dissolved inorganic carbon but also can alleviate ocean acidification.  相似文献   

18.
We conducted a meta-analysis of case–control studies to determine whether SELP genetic polymorphisms contribute to the pathogenesis of coronary heart disease (CHD) and myocardial infarction (MI). A range of electronic databases were searched: MEDLINE (1966–2013), the Cochrane Library Database (Issue 12, 2013), EMBASE (1980–2013), CINAHL (1982–2013), Web of Science (1945–2013) and the Chinese biomedical database (1982–2013) without language restrictions. Meta-analysis was performed with the use of the STATA statistical software. Nine case–control studies with a total of 3,154 CHD patients, 1,608 MI patients and 17,304 healthy controls were involved in this meta-analysis. Six common polymorphisms in the SELE gene were assessed, including ?1969G/A (rs1800805 G > A), ?1817T/C (rs1800808 T > C), ?2123C/G (rs1800807 C > G), Thr715Pro (rs6136 A > C), Leu599Val (rs6133 G > T), and Ser290Asn (rs6131 C > T). Our findings illustrated significantly positive associations of SELE genetic polymorphisms with the development of CHD and MI. The results of subgroup analysis by SNP type indicated that ?1969G/A, ?1817T/C, ?2123C/G, Thr715Pro and Ser290Asn in the SELP gene might be strongly correlated with CHD and MI risk, but no similar results were found in SELP Leu599Val polymorphism. In the subgroup analysis by ethnicity, our results indicated significant relationships between SELE genetic polymorphisms and the pathogenesis of CHD and MI among Asians and Caucasians. However, we observed no significant associations between SELP genetic polymorphisms and the risk of CHD and MI among Africans. Our findings provide empirical evidence that SELE genetic polymorphisms may contribute to the pathogenesis of CHD and MI, especially among Asians and Caucasians. Thus, SELP genetic polymorphisms could be potential and practical biomarkers for early diagnosis of CHD and MI.  相似文献   

19.
The Apolipoprotein A5 (APO A5) ?1131T/C, fibrinogen β (FgB) ?455G/A, ?148C/T, and cholesteryl ester transfer protein (CETP) TaqIB gene polymorphisms have been indicated to be associated with the coronary artery disease (CAD) risk, but the individual study results are still inconsistent. To explore the relationship between APO A5 ?1131T/C, FgB ?455G/A, ?148C/T, and CETP TaqIB gene polymorphisms and CAD in the Chinese population, the current meta-analysis involving 15,055 subjects from 40 individual studies was conducted. The pooled odds ratio (OR) for the association between APO A5 ?1131T/C, FgB ?455G/A, ?148C/T, and CETP TaqIB gene polymorphisms and CAD and its corresponding 95 % confidence interval (95 % CI) were evaluated by random or fixed effect model. A significant association between APO A5 ?1131T/C gene polymorphism and CAD in the Chinese population was found under an allelic (OR: 1.33, 95 % CI: 1.22–1.44, P < 0.00001), recessive (OR: 1.67, 95 % CI: 1.25–2.25, P = 0.0006), dominant (OR: 0.820, 95 % CI: 0.767–0.876, P = 1.0 × 10?10), homozygous (OR: 2.36, 95 % CI: 1.55–3.58, P < 0.0001) and heterozygous genetic models (OR: 1.136, 95 % CI:1.075–1.200, P = 1.0 × 10?10). A significant association between FgB ?455G/A gene polymorphism and CAD was also detected in the Chinese population under an allelic (OR: 1.50, 95 % CI: 1.25–1.81, P < 0.0001), dominant (OR: 0.864, 95 % CI: 0.819–0.912, P = 1.0 × 10?10), homozygous (OR: 1.616, 95 % CI: 1.213–2.152, P = 0.001) and heterozygous genetic models (OR: 1.245, 95 % CI:1.138–1.361, P = 1.0 × 10?10). No significant association was found between them under a recessive genetic model (OR: 1.124, 95 % CI: 0.844–1.497, P = 0.424). A significant association was also found between FgB ?148C/T gene polymorphism and CAD in the Chinese population under an allelic (OR: 1.34, 95 % CI: 1.06–1.71, P = 0.02), recessive (OR: 1. 65, 95 % CI: 1.02–2.69, P = 0.04), dominant (OR: 0.924, 95 % CI: 0.872–0.978, P = 0.007) and homozygous genetic models (OR: 0.968, 95 % CI: 0.942–0.995, P = 0.018). No significant association was found between them under a heterozygous genetic model (OR: 0.979, 95 % CI: 0.937–1.023, P = 0.342). In the whole Chinese population, no significant association between the CETP TaqIB gene polymorphism and CAD was found under an allelic (OR: 1.17, 95 % CI: 0.94–1.45, P = 0.15), dominant (OR: 1.46, 95 % CI: 0.80–2.67, P = 0.22) or recessive genetic models (OR: 0.68, 95 % CI: 0.32–1.44, P = 0.31). However, in the subgroup analysis stratified by ethnicity, there was a significant association between them under an allelic (OR: 1.27, 95 % CI: 1.07–1.52, P = 0.007) and dominant genetic model (OR: 2.04, 95 % CI: 1.49–2.79, P < 0.00001) in the Han subgroup. In the Chinese population, the APO A5 ?1131T/C and FgB ?455G/A, ?148C/T gene polymorphisms were implied to be associated with CAD susceptibility. The APO A5 ?1131C, FgB ?455A, and ?148T alleles might confer susceptibility to CAD. CETP TaqIB gene polymorphism was suggested to be associated with CAD susceptibility in the Chinese Han population. Carriers with B1 allele of CETP TaqIB gene might be predisposed to CAD in the Chinese Han population.  相似文献   

20.
Tidal wetlands are productive ecosystems with the capacity to sequester large amounts of carbon (C), but we know relatively little about the impact of climate change on wetland C cycling in lower salinity (oligohaline and tidal freshwater) coastal marshes. In this study we assessed plant production, C cycling and sequestration, and microbial organic matter mineralization at tidal freshwater, oligohaline, and salt marsh sites along the salinity gradient in the Delaware River Estuary over four years. We measured aboveground plant biomass, carbon dioxide (CO2) and methane (CH4) exchange between the marsh and atmosphere, microbial sulfate reduction and methanogenesis in marsh soils, soil biogeochemistry, and C sequestration with radiodating of soils. A simple model was constructed to estimate monthly and annually integrated rates of gross ecosystem production (GEP), ecosystem respiration (ER) to carbon dioxide ( \( {\text{ER}}_{{{\text{CO}}_{2} }} \) ) or methane ( \( {\text{ER}}_{{{\text{CH}}_{4} }} \) ), net ecosystem production (NEP), the contribution of sulfate reduction and methanogenesis to ER, and the greenhouse gas (GHG) source or sink status of the wetland for 2 years (2007 and 2008). All three marsh types were highly productive but evidenced different patterns of C sequestration and GHG source/sink status. The contribution of sulfate reduction to total ER increased along the salinity gradient from tidal freshwater to salt marsh. The Spartina alterniflora dominated salt marsh was a C sink as indicated by both NEP (~140 g C m?2 year?1) and 210Pb radiodating (336 g C m?2 year?1), a minor sink for atmospheric CH4, and a GHG sink (~620 g CO2-eq m?2 year?1). The tidal freshwater marsh was a source of CH4 to the atmosphere (~22 g C–CH4 m?2 year?1). There were large interannual differences in plant production and therefore C and GHG source/sink status at the tidal freshwater marsh, though 210Pb radiodating indicated modest C accretion (110 g C m?2 year?1). The oligohaline marsh site experienced seasonal saltwater intrusion in the late summer and fall (up to 10 mS cm?1) and the Zizania aquatica monoculture at this site responded with sharp declines in biomass and GEP in late summer. Salinity intrusion was also linked to large effluxes of CH4 at the oligohaline site (>80 g C–CH4 m?2 year?1), making this site a significant GHG source (>2,000 g CO2-eq m?2 year?1). The oligohaline site did not accumulate C over the 2 year study period, though 210Pb dating indicated long term C accumulation (250 g C m?2 year?1), suggesting seasonal salt-water intrusion can significantly alter C cycling and GHG exchange dynamics in tidal marsh ecosystems.  相似文献   

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