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21.

Introduction

Polycystic Ovary Syndrome (PCOS) is a complex endocrine disorder, of multifactorial etiology, which affects 6–10% of women of reproductive age. It is considered the leading cause of anovulatory infertility, menstrual disorders and hyperandrogenism in this population. The genetic basis of PCOS is still largely unknown despite significant family clustering; determining its mode of inheritance is particularly difficult given the heterogenic presentation of the disease.

Materials and methods

130 Brazilian women, aged 14–42 years, who met the 2003 Rotterdam criteria for PCOS diagnosis, were included, and 96 healthy women constituted the control group. Presence of hirsutism was classified using the modified Ferriman–Gallwey score (F–G score) as absent (≤ 7), mild (8–14), and severe (≥ 15). Blood levels of luteinizing hormone (LH), total testosterone (TT), dehydroepiandrosterone sulfate (DHEA-S) and androstenedione were determined. The coding region of the luteinizing hormone beta-subunit (LHB) gene was amplified and sequenced. Differences in allelic and genotypic frequency distribution of each polymorphism across controls and cases were estimated by the Mantel–Haenszel chi-square or Fisher's exact test (p < 0.05), and the probability of an association between the detection of a polymorphism and presence of a diagnosis of PCOS, by logistic regression.

Result(s)

Sequencing detected 8 polymorphisms in the LHB gene coding region. Two polymorphisms in linkage disequilibrium were significantly more prevalent in the presence of hyperandrogenemia: rs1800447/rs34349826 (Trp28Arg/Ile35Thr) (p = 0.02).

Conclusion(s)

In this series, a modulatory effect of LHB polymorphisms on hyperandrogenemia phenotype of PCOS was observed; however, this finding needs to be replicated in other populations.  相似文献   
22.
目的:探讨不同全自动凝血分析仪检测结果是否具有可比性,同时对其检测结果临床可接受性进行评估,使不同全自动凝血分析仪检测结果标准化.方法:连续30天用SYSMEX CA- 1500及CA-7000全自动凝血分析仪同时检测并比对仪器配套定值质控物的PT、INR、APTT、FIB、TT值;同时连续30天利用两台仪器检测并对比新鲜血标本的PT、INR、APTT、FIB、TT值.结果:SYSMEX CA- 1500及CA-7000日间质控物各检测项目:PT、INR、APTT、FIB、TT变异系数均小于5%.CA- 1500及CA-7000全自动凝血分析仪检测新鲜血标本:PT、INR、APTT、FIB、TT统计分析结果,t检验其P值均>0.05;相关系数r在0.993-0.999之间;两台仪器的偏差均符合1/2美国CLIA’88能力验证分析质量要求.结论:两台仪器PT、INR、APTT、FIB、TT的检测结果具有很好的相关性,经统计分析两台仪器检测结果无统计学意义.对不同凝血分析仪进行比对分析,不仅能够及时发现仪器存在的系统误差.而且使其检测结果具有很好的一致性,给临床可提供一个准确、可靠一致的实验室检测结果,使临床对疾病的诊断、疗效观察有一个统一的评判标准.  相似文献   
23.
One of the main obstacles in the development of a vaccine against Pseudomonas aeruginosa is the requirement that it is protective against a wide range of virulent strains. We have developed a synthetic-peptide consensus-sequence vaccine (Cs1) that targets the host receptor-binding domain (RBD) of the type IV pilus of P. aeruginosa. Here, we show that this vaccine provides increased protection against challenge by the four piliated strains that we have examined (PAK, PAO, KB7 and P1) in the A.BY/SnJ mouse model of acute P. aeruginosa infection. To further characterize the consensus sequence, we engineered Cs1 into the PAK monomeric pilin protein and determined the crystal structure of the chimeric Cs1 pilin to 1.35 Å resolution. The substitutions (T130K and E135P) used to create Cs1 do not disrupt the conserved backbone conformation of the pilin RBD. In fact, based on the Cs1 pilin structure, we hypothesize that the E135P substitution bolsters the conserved backbone conformation and may partially explain the immunological activity of Cs1. Structural analysis of Cs1, PAK and K122-4 pilins reveal substitutions of non-conserved residues in the RBD are compensated for by complementary changes in the rest of the pilin monomer. Thus, the interactions between the RBD and the rest of the pilin can either be mediated by polar interactions of a hydrogen bond network in some strains or by hydrophobic interactions in others. Both configurations maintain a conserved backbone conformation of the RBD. Thus, the backbone conformation is critical in our consensus-sequence vaccine design and that cross-reactivity of the antibody response may be modulated by the composition of exposed side-chains on the surface of the RBD. This structure will guide our future vaccine design by focusing our investigation on the four variable residue positions that are exposed on the RBD surface.  相似文献   
24.
拟南芥TT1(transparenttesta1)基因编码一个WIP类型锌指蛋白转录因子,调控内种皮发育和原花青素在内种皮的积累。本研究通过PCR扩增了甘蓝型油菜(Brassicanapus)TT1基因家族(BnTT1)的一段特异保守片段TT1A,并将其亚克隆到中间载体pCambia2301G中,构建了TT1反义植物表达载体pCambia2301G-TT1A,通过PCR鉴定、酶切鉴定和DNA测序证实载体构建成功,并转化到根癌农杆菌LBA4404菌株中形成工程菌株。此表达载体的构建为进一步研究TT1基因在甘蓝型油菜种皮色素合成途径中的分子生物学机理和利用反义TT1基因遗传转化获得转基因新型黄籽油菜奠定了基础。  相似文献   
25.

Aim

To analyze the effect of the two different versions of the manganese superoxide dismutase gene (SOD2) on sepsis. The SOD2 gene presents the 47C > T single nucleotide polymorphism (SNP; ID: rs4880) which produces MnSOD with different activities. The − 9Val MnSOD (47T allele) is less efficient than the − 9Ala version (47C allele). During sepsis there are abundance of ROS, high SOD2 expression and excess of H2O2 synthesis. High concentrations of H2O2 could affect the sepsis scenario and/or the sepsis outcome.

Methods

We determined the 47C > T single nucleotide polymorphism (SNP) frequencies in 529 critically ill patients with or without sepsis, facing outcome. To collect information on population frequencies, we obtained a pilot 47C > T genotypic and allelic frequencies in a random group of 139 healthy subjects.

Results

We compared the 47C allele carriers (47CC + 47CT genotypes) with 47TT homozygotes and noticed a significant association between 47C allele carriers and septic shock in septic patients (P = 0.025). With an adjusted binary multivariate logistic regression, incorporating 47C > T SNP and the main clinical predictors, we showed high SOFA scores [P < 0.001, OR = 9.107 (95% CI = 5.319–15.592)] and 47C allele [P = 0.011, OR = 2.125 (95% CI = 1.190–3.794)] were significantly associated with septic shock outcome. With this information we presented a hypothesis suggesting that this negative outcome from sepsis is possibly explained by effects on cellular stress caused by 47C allele.

Conclusion

In our population there was a significant higher frequency of septic shock in septic patients with the 47C allele of the SOD2 gene. This higher 47C allele frequency in septic patients with negative outcome could be explained by effects of higher activity MnSOD on cellular stress during the sepsis.  相似文献   
26.
Dinoflagellates are microalgae that are associated with the production of many marine toxins. These toxins poison fish, other wildlife and humans. Dinoflagellate-associated human poisonings include paralytic shellfish poisoning, diarrhetic shellfish poisoning, neurotoxic shellfish poisoning, and ciguatera fish poisoning. Dinoflagellate toxins and bioactives are of increasing interest because of their commercial impact, influence on safety of seafood, and potential medical and other applications. This review discusses biotechnological methods of identifying toxic dinoflagellates and detecting their toxins. Potential applications of the toxins are discussed. A lack of sufficient quantities of toxins for investigational purposes remains a significant limitation. Producing quantities of dinoflagellate bioactives requires an ability to mass culture them. Considerations relating to bioreactor culture of generally fragile and slow-growing dinoflagellates are discussed. Production and processing of dinoflagellates to extract bioactives, require attention to biosafety considerations as outlined in this review.  相似文献   
27.
Brown cotton fibres are the most widely used naturally coloured raw materials for the eco‐friendly textile industry. Previous studies have indicated that brown fibre pigments belong to proanthocyanidins (PAs) or their derivatives, and fibre coloration is negatively associated with cotton productivity and fibre quality. To date, the molecular basis controlling the biosynthesis and accumulation of brown pigments in cotton fibres is largely unknown. In this study, based on expressional and transgenic analyses of cotton homologs of ArabidopsisPA regulator TRANSPARENT TESTA 2 (TT2) and fine‐mapping of the cotton dark‐brown fibre gene (Lc1), we show that a TT2 homolog, GhTT2‐3A, controls PA biosynthesis and brown pigmentation in cotton fibres. We observed that GhTT2‐3A activated GhbHLH130D, a homolog of ArabidopsisTT8, which in turn synergistically acted with GhTT2‐3A to activate downstream PA structural genes and PA synthesis and accumulation in cotton fibres. Furthermore, the up‐regulation of GhTT2‐3A in fibres at the secondary wall‐thickening stage resulted in brown mature fibres, and fibre quality and lint percentage were comparable to that of the white‐fibre control. The findings of this study reveal the regulatory mechanism controlling brown pigmentation in cotton fibres and demonstrate a promising biotechnological strategy to break the negative linkage between coloration and fibre quality and/or productivity.  相似文献   
28.
采用抗原加倍方法用于成率率低于705群的巴匹免疫,结果显示,进一步免疫成功的马匹明显多于常规免疫(P<0.05),免疫效价和死亡率无明显变化(P>0.05)。  相似文献   
29.
In humans, NKG2D is an activating receptor on natural killer (NK) cells and a costimulatory receptor on certain T cells and plays a central role in mediating immune responses in autoimmune diseases, infectious diseases, and cancer. Monoclonal antibodies that antagonize or agonize immune responses mediated by human NKG2D are considered to be of broad and potent therapeutic utility. Nonetheless, monoclonal antibodies to NKG2D that are suitable for clinical investigations have not been published yet. Here, we describe the generation, affinity maturation, and characterization of a fully human monoclonal antibody to human NKG2D. Using phage display technology based on a newly generated naïve human Fab library in phage display vector pC3C followed by a tandem chain shuffling process designed for minimal deviation from natural human antibody sequences, we selected a human Fab, designated KYK-2.0, with high specificity and affinity to human NKG2D. KYK-2.0 Fab blocked the binding of the natural human NKG2D ligands MICA, MICB, and ULBP2 as potently as a commercially available mouse anti-human NKG2D monoclonal antibody in immunoglobulin G (IgG) format. Conversion of KYK-2.0 Fab to IgG1 resulted in subnanomolar avidity for human NKG2D. KYK-2.0 IgG1 was found to selectively recognize defined subpopulations of human lymphocytes known to express NKG2D, that is, the majority of human CD8+, CD16+, and CD56+ cells as well as a small fraction of human CD4+ cells. In solution, KYK-2.0 IgG1 interfered with the cytolytic activity of ex vivo expanded human NK cells. By contrast, immobilized KYK-2.0 IgG1 was found to strongly induce human NK cell activation. The dual antagonistic and agonistic activity promises a wide range of therapeutic applications for KYK-2.0 IgG1 and its derivatives.  相似文献   
30.
The aim of the present study was to develop mannosylated niosomes as oral vaccine delivery carrier and adjuvant for the induction of humoral, cellular, and mucosal immunity. Tetanus toxoid (TT) loaded niosomes composed of sorbiton monostearate (Span 60), cholesterol, and stearylamine were prepared by the reverse-phase evaporation method. They were coated with a modified polysaccharide o-palmitoyl mannan (OPM) to protect them from bile salts caused dissolution and enzymatic degradation in the gastrointestinal tract and to enhance their affinity toward the antigen presenting cells of Peyer's patches. Prepared niosomes were characterized in vitro for their size, shape, entrapment efficiency, ligand binding specificity, and stability in simulated gastric fluid and simulated intestinal fluid. OPM-coated niosomes were found to more stable in simulated gastrointestinal conditions. The immune stimulating activity was studied by measuring serum IgG titer, IgG2a/IgG1 ratio in serum, and sIgA levels in intestinal and salivary secretions following oral administration of niosomal formulations in albino rats. The results were compared with alum-adsorbed TT following oral and intramuscular administration, and it was observed that OPM-coated niosomes produced better IgG levels as compared to plain uncoated niosomes and alum-adsorbed TT upon oral administration. Oral niosomes also elicited a significant mucosal immune response (sIgA levels in mucosal secretions). The developed formulations also elicited a combined serum IgG2a/IgG1 response, suggesting that they were capable of eliciting both humoral and cellular response. The study signifies the potential of OPM-coated niosomes as an oral vaccine delivery carrier and adjuvant. The proposed system is simple, stable, and cost-effective and may be clinically acceptable.  相似文献   
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