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1.
Omega-3 long-chain polyunsaturated fatty acid (n-3 LC-PUFA), especially eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), are essential nutrients for human health. However, vertebrates, including humans, have lost the abilities to synthesize EPA and DHA de novo, majorly due to the genetic absence of delta-12 desaturase and omega-3 desaturase genes. Fishes, especially those naturally growing marine fish, are major dietary source of EPA and DHA. Because of the severe decline of marine fishery and the decrease in n-3 LC-PUFA content of farmed fishes, it is highly necessary to develop alternative sources of n-3 LC-PUFA. In the present study, we utilized transgenic technology to generate n-3 LC-PUFA-rich fish by using zebrafish as an animal model. Firstly, fat1 was proved to function efficiently in fish culture cells, which showed an effective conversion of n-6 PUFA to n-3 PUFA with the n-6/n-3 ratio that decreased from 7.7 to 1.1. Secondly, expression of fat1 in transgenic zebrafish increased the 20:5n-3 and 22:6n-3 contents to 1.8- and 2.4-fold, respectively. Third, co-expression of fat2, a fish codon-optimized delta-12 desaturase gene, and fat1 in fish culture cell significantly promoted n-3 PUFA synthesis with the decreased n-6/n-3 ratio from 7.7 to 0.7. Finally, co-expression of fat1 and fat2 in double transgenic zebrafish increased the 20:5n-3 and 22:6n-3 contents to 1.7- and 2.8-fold, respectively. Overall, we generated two types of transgenic zebrafish rich in endogenous n-3 LC-PUFA, fat1 transgenic zebrafish and fat1/fat2 double transgenic zebrafish. Our results demonstrate that application of transgenic technology of humanized fat1 and fat2 in farmed fishes can largely improve the n-3 LC-PUFA production.  相似文献   

2.
Meng Q  Guo H  Hou S  Jiang Z  Kijlstra A  Yang P 《PloS one》2011,6(10):e25345

Background

Behcet''s disease is a chronic, multi-systemic autoimmune disease. Programmed cell death 1 (PD-1) gene is one of non-human leucocyte antigen genes. It has been demonstrated to be associated with several autoimmune diseases. However, only a few studies have addressed the association of ligand genes of PD-1, PD-L1 and PD-L2 with autoimmune disease. The purpose of this study was to analyze the potential association of the PD-1 and its ligand genes with Behcet''s disease in a Chinese Han population.

Methodology/Principal Findings

Four single-nucleotide polymorphism (SNPs) rs2227981 and rs10204525 of PD-1, rs1970000 of PD-L1 and rs7854303 of PD-L2 were genotyped in 405 Behcet''s patients and 414 age-, sex-, ethnic-matched healthy controls using polymerase chain reaction-restriction fragment length polymorphism assay. The results revealed that there were no significant differences in the genotype and allele frequencies of PD-1 rs2227981 and rs10204525 between the Behcet''s patients and controls. A similar result was found for PD-L1 rs1970000 versus healthy controls. Only the C allele and the CC genotype of PD-L2 rs7854303 were identified in patients and controls. Stratification analysis based on gender and clinical findings did not show any associations between PD-1 or its ligand polymorphisms and Behcet''s disease.

Conclusions/Significance

None of the currently studied SNPs, PD-1 rs2227981 and rs10204525, PD-L1 rs1970000 and PD-L2 rs7854303, are associated with the susceptibility to Behcet''s disease in a Chinese Han population. More studies are needed to confirm these findings in Behcet''s patients with other ethnic backgrounds.  相似文献   

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4.

Objective

To conduct a meta-analysis of all published genetic association studies of 5-HTTLPR polymorphisms performed in PTSD cases

Methods Data Sources

Potential studies were identified through PubMed/MEDLINE, EMBASE, Web of Science databases (Web of Knowledge, WoK), PsychINFO, PsychArticles and HuGeNet (Human Genome Epidemiology Network) up until December 2011. Study Selection: Published observational studies reporting genotype or allele frequencies of this genetic factor in PTSD cases and in non-PTSD controls were all considered eligible for inclusion in this systematic review. Data Extraction: Two reviewers selected studies for possible inclusion and extracted data independently following a standardized protocol. Statistical analysis: A biallelic and a triallelic meta-analysis, including the total S and S'' frequencies, the dominant (S+/LL and S''+/L''L'') and the recessive model (SS/L+ and S''S''/L''+), was performed with a random-effect model to calculate the pooled OR and its corresponding 95% CI. Forest plots and Cochran''s Q-Statistic and I2 index were calculated to check for heterogeneity. Subgroup analyses and meta-regression were carried out to analyze potential moderators. Publication bias and quality of reporting were also analyzed.

Results

13 studies met our inclusion criteria, providing a total sample of 1874 patients with PTSD and 7785 controls in the biallelic meta-analyses and 627 and 3524, respectively, in the triallelic. None of the meta-analyses showed evidence of an association between 5-HTTLPR and PTSD but several characteristics (exposure to the same principal stressor for PTSD cases and controls, adjustment for potential confounding variables, blind assessment, study design, type of PTSD, ethnic distribution and Total Quality Score) influenced the results in subgroup analyses and meta-regression. There was no evidence of potential publication bias.

Conclusions

Current evidence does not support a direct effect of 5-HTTLPR polymorphisms on PTSD. Further analyses of gene-environment interactions, epigenetic modulation and new studies with large samples and/or meta-analyses are required.  相似文献   

5.
《PloS one》2013,8(7)

Objectives

To compare the dopaminergic neuronal imaging features of different subtypes of genetic Parkinson''s Disease.

Methods

A retrospective study of genetic Parkinson''s diseases cases in which DaTSCAN (123I-FP-CIT) had been performed. Specific non-displaceable binding was calculated for bilateral caudate and putamen for each case. The right:left asymmetry index and striatal asymmetry index was calculated.

Results

Scans were available from 37 cases of monogenetic Parkinson''s disease (7 glucocerebrosidase (GBA) mutations, 8 alpha-synuclein, 3 LRRK2, 7 PINK1, 12 Parkin). The asymmetry of radioligand uptake for Parkinson''s disease with GBA or LRRK2 mutations was greater than that for Parkinson''s disease with alpha synuclein, PINK1 or Parkin mutations.

Conclusions

The asymmetry of radioligand uptake in Parkinsons disease associated with GBA or LRRK2 mutations suggests that interactions with additional genetic or environmental factors may be associated with dopaminergic neuronal loss.  相似文献   

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8.
Regulation of anthocyanin biosynthesis in peach fruits   总被引:2,自引:0,他引:2  
  相似文献   

9.
CD4+ T cells orchestrate the immune response by differentiating into T helper (Th) or regulatory (Treg) cell subsets that secrete distinct sets of cytokines. They also play a critical role in the pathogenesis of autoimmunity, asthma, allergy and, likely, cancer. The mechanisms involved in the regulation of CD4+ T cell homeostasis by galectin-1 remain poorly characterized. To investigate whether galectin-1 modulates the differentiation of CD4+ T cells, the effects of galectin-1 on the mRNA expression levels of TBX21, GATA-3, FOXP3 and RORC in activated peripheral blood mononuclear cells were examined. The expression levels of GATA-3 and FOXP3 mRNA were up-regulated after treatment with 1.0 μg/ml galectin-1 and were unchanged (for GATA-3) or slightly elevated (for FOXP3) compared with untreated cells when 2.0 μg/ml galectin-1 was added. At the same time, at both concentrations of galectin-1, we observed reduced TBX21 and RORC mRNA expression levels. These findings support the concept that galectin-1 skews the differentiation of CD4+ T cells towards Th2 and Treg cells.  相似文献   

10.
The infectivity of five populations of Tylenchulus semipenetrans were compared and differentiated on 10 hosts (5 Citrus spp., 1 Poncirus trifoliata, and 4 hybrids of Citrus spp. X P. trifoliata). Differences in levels of infection and development (P = 0.01) occurred between Citrus spp. and P. trifoliata cv. ''Pomeroy'' and their three hybrids, C. paradisi X P. trifoliata cv. ''Swingle'' citruntelo and C. sinensis, cv. ''Ruby'' orange X P. trifoliata cv. ''Webber Fawcett 14-7'', and ''15-7''. Poncirus trifoliata cv. Pomeroy was susceptible to a California biotype 3 and highly resistant to the other citrus nematode populations. Low infection levels with California biotype 1, Arizona, and Florida populations on Swingle citrumelo, and the two Ruby orange hybrids indicated inherited resistance. Reproduction of the nematode population from Texas was greatest on the three hybrids, Swingle citrumelo, Ruby orange 14-7, and 15-7, from the California 1, Arizona, and Florida populations, but its comparable densities on P. trifoliata and Citrus spp. were not sufficiently different from these populations to consider it a separate biotype. California biotype 3 was sufficiently different from all other populations to be considered a different biotype, and it was named the "Poncirus biotype."  相似文献   

11.

Background

Lung infection by various organisms is a characteristic feature of cystic fibrosis (CF). CFTR genotype effects acquisition of Pseudomonas aeruginosa (Pa), however the effect on acquisition of other infectious organisms that frequently precede Pa is relatively unknown. Understanding the role of CFTR in the acquisition of organisms first detected in patients may help guide symptomatic and molecular-based treatment for CF.

Methods

Lung infection, defined as a single positive respiratory tract culture, was assessed for 13 organisms in 1,381 individuals with CF. Subjects were divided by predicted CFTR function: ''Residual'': carrying at least one partial function CFTR mutation (class IV or V) and ''Minimal'' those who do not carry a partial function mutation. Kaplan-Meier estimates were created to assess CFTR effect on age of acquisition for each organism. Cox proportional hazard models were performed to control for possible cofactors. A separate Cox regression was used to determine whether defining infection with Pa, mucoid Pa or Aspergillus (Asp) using alternative criteria affected the results. The influence of severity of lung disease at the time of acquisition was evaluated using stratified Cox regression methods by lung disease categories.

Results

Subjects with ''Minimal'' CFTR function had a higher hazard than patients with ''Residual'' function for acquisition of 9 of 13 organisms studied (HR ranging from 1.7 to 3.78 based on the organism studied). Subjects with minimal CFTR function acquired infection at a younger age than those with residual function for 12 of 13 organisms (p-values ranging: < 0.001 to 0.017). Minimal CFTR function also associated with younger age of infection when 3 alternative definitions of infection with Pa, mucoid Pa or Asp were employed. Risk of infection is correlated with CFTR function for 8 of 9 organisms in patients with good lung function (>90%ile) but only 1 of 9 organisms in those with poorer lung function (<50%ile).

Conclusions

Residual CFTR function correlates with later onset of respiratory tract infection by a wide spectrum of organisms frequently cultured from CF patients. The protective effect conferred by residual CFTR function is diminished in CF patients with more advanced lung disease.  相似文献   

12.
The aim of the present study was to establish the gene frequency of six polymorphisms of the ABCB1, CYP3A5, CYP2C19, and P2RY12 genes in a population resident of Mexico City. The proteins encoded by these genes have been associated with the absorption, and biotransformation of clopidogrel. The ABCB1 T3435C, CYP3A5 V3* A6986G, P2RY12 G52T, P2RY12 C34T, CYP2C19 V2* and V3* (positions G681A and G636A, respectively), polymorphisms were analyzed by 5′ exonuclease TaqMan genotyping assays in a group of 269 healthy unrelated Mexican Mestizo individuals. The CYP2C19 V3* G636A polymorphism was not detected in the Mexican Mestizos population. However, the studied population presented significant differences (P < 0.05) in the distribution of the T3435C, A6986G, G681A, G52T and C34T polymorphisms when compared to reported frequencies of Amerindian of South America, Caucasian, Asian, and African populations. In summary, the distribution of the ABCB1, CYP3A5, CYP2C19, and P2RY12 gene polymorphisms distinguishes to the Mexican Mestizos population from other ethnic groups.  相似文献   

13.
C3 phenotypes were examined in species of Papio and Macaca. Baboons (P. cynocephalus) showed extensive polymorphism, with estimated gene frequencies of 0.815, 0.174, and 0.011 for C3*S, C3*F, and C3*F 1 alleles, respectively. Clear segregation patterns showing codominant inheritance were evident in family studies. Such extensive polymorphism was not observed in M. nemestrina or M. fascicularis. The S gene is the most common allele in all the species studied. The F gene is relatively common in baboons.  相似文献   

14.

Objectives

We have examined dynamic changes of histone H3 lysine 9 following trimethylation (H3K9me3), the mRNA expression levels of SUV39H1 and SUV39H2 in bovine oocytes and the role in the development of in vitro fertilization (IVF) pre-implantation embryos.

Results

There were strong H3K9me3 signals in germinal vesicle (GV) oocytes but no signals in MII oocytes. H3K9me3 signals were maintained during IVF pre-implantation embryo development. SUV39H1 and SUV39H2 showed significantly higher mRNA expression levels in GV oocytes than MII oocytes (P < 0.01). SUV39H1 showed high mRNA expression level in two-cell embryos, however, SUV39H2 showed high mRNA expression level in four-cell embryos. In other development stage, SUV39H1 and SUV39H2 showed low expression levels.

Conclusion

Bovine IVF pre-implantation embryos maintain strong H3K9me3 signals and SUV39H1 and SUV39H2 are highly expressed at the early development stage of pre-implantation embryos.
  相似文献   

15.
A bio-guided fractionation of the 80% aqueous ethanolic extract of the aerial parts of Silene gallica L. (Caryophyllaceae), growing in North-Eastern Algeria, was performed to evaluate its antioxidant activity using DPPH, hydroxyl radical scavenging and CUPRAC assays. Successive chromatographic separations of the most antioxidant n-BuOH soluble fraction yielded four acylated flavone C-glycosides, vitexin 2''-O-β-d-(4''',6'''-di-acetyl)-glucopyranoside (1), orientin-2''-O-β-d-(4''',6'''-di-acetyl)-glucopyranoside (2), orientin-2''-O-β-d-(6'''-feruloyl)-glucopyranoside (3), and orientin-2''-O-β-d-(6'''-sinapoyl)-glucopyranoside (4), as well as six known compounds including four flavonoids (5-8), a phenylpropanoid glycerolglucoside (regaloside A) (9), and a phytoecdysteroide (20-hydroxyecdysone) (10). Their structures were established by UV, 1D, 2D NMR, and HR-ESI-MS spectral data, in addition to comparison with literature data. The antioxidant activity of the crude extracts, fractions and compounds 1-8 was evaluated. Two acylated orientin glycosides (3 and 4) displayed the strongest antioxidant activity.  相似文献   

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18.
In an 8-year sod-based rotation study, nematode population densities varied with different row-crop sequences and grass sods. In continuous row-crop rotations (cotton-corn-peanut), cotton and corn favored rapid increase of Belonolaimus longicaudatus and Trichodorus christiei. Numbers of Pratylenchus brachyurus were quite variable on all crops. Peanuts favored an increase of Criconemoides ornatum but suppressed the other three species. ''Coastal'' bermudagrass supported more than twice the number of B. longicaudatus than did ''Pensacola'' bahiagrass. Numbers of T. christiei and P. brachyurus also were larger on bermudagrass than on bahiagrass. Numbers of C. ornatum were largest in row-crop sequence culture. Average numbers of B. longicaudatus, T. christiei, and P. brachyurus in a sod-based, 3-years of row-crop sequence were smallest when cotton and corn did not follow each other. These nematodes were further suppressed when the sequence corn-peanut-cotton followed bahiagrass. Numbers of C. ornatum were smallest when corn and cotton followed each other, except after 3 years of bahiagrass. Nematode populations were less influenced by row-crop sequence following bermudagrass than they were following bahiagrass.  相似文献   

19.
The structure of an hypothesized hybrid or “Lepore-type” IgG contained in the serum of donor 2904 was investigated. Previous immunological studies suggested that this serum contained IgG with aγ3-γ1 hybrid heavy chain consisting of aγ3 Fd portion and aγ1 Fc. Structural studies have now shown that the carboxyl terminal end of the 2904 hybrid IgG, including much of the Fc fragment, isγ1 in character. However, the fingerprints of the Fc tryptic peptides at both pH 3.6 and pH 6.4 included a peptide, possibly from the hinge region, in peptide maps of Fc from aγG3 Gm (5) myeloma protein, but absent from maps of Fc peptides fromγG1 proteins. Gel filtration of the CNBr fragments of Fc from 2904 suggested that the hinge region isγ3-like. Papain cleavage experiments indicated an elevated level of resistant IgG, which agrees with immunological findings of an increasedγG2 subclass level. Our data confirm previous reports that theγ chain C-terminal octadecapeptides fromγG3 proteins have a subclass specific residue of arginine and indicate that within this subclass there is an allotypic variation related to the Gm type of the protein.  相似文献   

20.
Some recombinant proteins expressed by baculovirus expression vector systems (BEVS) aggregate because the BEVS can produce large amounts of protein late during infection, when post-translational modification and protein quality control mechanisms are inactive. For expression during earlier stages than that driven by the polyhedrin (polh) very late promoter, transfer vectors were generated in which this promoter was replaced with a green fluorescent protein (GFP) gene controlled by a vp39 late promoter modified to contain HR3, one of the homologous DNA regions (HRs) of Bombyx mori nuclear polyhedrosis virus (BmNPV). The rise times of the fluorescence of GFP expressed by using recombinant viruses carrying the modified vp39 promoter were earlier than those associated with either the polh promoter or the native vp39 promoter lacking HR3. In transient expression assays, the vp39 late promoter in transfer vectors behaved like a delayed-early promoter, and was enhanced by HR3, and required IE-1 protein and various viral gene products encoded on both sides of BmNPV polh. When the vp39 promoter with HR3 was used, the aggregation of several foreign proteins expressed by the BEVS was markedly decreased. This study provides a new option for the expression of sufficiently quality-controlled proteins by using the vp39 promoter and HR3 in BEVS early in baculovirus infection, when the infection has caused little damage in the host cells.  相似文献   

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