Chlamydia trachomatis and sperm lipid peroxidation in infertile men

Aim：To relate thepresence of anti-Chlamydial trachomatis IgA in semen with sperm lipid membrane peroxidation and changes in seminal parameters.Methods:Semen samples of the male partners of 52 couples assessed for undiagnosed infertility were examined for the presence of IgA antibody against C.trachomatis.The level of sperm membrane lipid peroxidation was estimated by determining the malondialdehyde(MDA) formation.Results:Sperm membrane of infertile males with positive IgA antibodies against C.trachomatis showed a higher level of lipid peroxidation than that of infertile males with negative IgA antibody(P<0.05).There was a positive correlation(P<0.01) between the level of C.trachomatis antibody and the magnitude of sperm membrane lipid peroxidation.All the other tested semen parameters were found to be similar in the two groups.Conclusion:The activation of immune system by C.trachomatis may promote lipid peroxidation of the sperm membrane.This could be the way by which C.trachomatis affects fertility.

TCF7L2 rs7903146 polymorphism is associated with gastric cancer: a case-control study in the Venezuelan population

AIM: To explore the association between TCF7L2 rs12255372 and rs7903146 single nucleotide polymorphisms(SNPs) and gastric cancer risk in Venezuelan patients.METHODS: We performed a case-control study including 122 paraffin-embedded archived intestinaltype gastric cancer samples and 129 biopsies obtained by superior endoscopy from chronic gastritis patients. Gastric cancer samples were classified according the degree of carcinoma differentiation. Genomic DNA was extracted from tissues, and the two SNPs of TCF7L2 gene(rs12255372 and rs7903146) were genotyped by polymerase chain reaction-restriction fragment length polymorphism reactions. Multiple regression analysis with adjustments for age and gender were performed and best-fitting models of inheritance were determined.RESULTS: After adjusting for age and sex the TCF7L2 rs7903146 TT genotype was associated with gastric cancer risk under the recessive genetic model(OR = 3.11, 95%CI: 1.22-7.92, P = 0.017). We further investigated the distribution of rs12255372 and rs7903146 genotypes according gastric cancer stratified by degree of differentiation, and we observed that carriers of rs7903146 T allele(CT + TT vs CC) had a significantly increased risk of moderate/well differentiated gastric cancer(dominant model, OR = 2.55, 95%CI: 1.35-4.80, P = 0.004), whereas the rs7903146 TT genotype was associated with poorly differentiated gastric cancer in the recessive model(OR = 3.65, 95%CI: 1.25-10.62, P = 0.018). We did not find association between rs12255372 SNP and the susceptibility of developing gastric cancer. CONCLUSION: TCF7L2 rs7903146 polymorphism is associated with gastric cancer risk in the Venezuelan population, and could be related to determine the degree of differentiation of tumor cells.

微生物生长模型的极限环(英文)

讨论了一个一般的微生物生长模型的极限环问题。证明了周期解的存在条件,并估计了有关极限环的周长和相对位置。本文的结果对深入研究微生物生长系统的震荡现象是非常有用的。

Semantic framework of event detection in emergency situations for smart buildings

Multimedia Sensor Networks(MSNs)have enhanced the ability to analyze the environment and provide responses based on its current status.Generally,MSNs are composed of scalar and multimedia sensors that have fixed locations.However,given the advancement of smart mobile device technologies,it is currently possible to dynamically integrate mobile sensors into MSNs.In this paper,we propose a formal platform to manage MSNs and the data gathered from them to detect complex events.Our main contributions include:M^(2)SSN-Onto,a Mobile and Multimedia Semantic Sensor Networks Ontology;Py-CEMiD,an engine for detecting complex events and generate reactions to them;a mobile device location engine to locate mobile sensors;and a proof-of-concept in the context of detecting emergency situations in smart buildings.Several scenarios are validated for emergency events,combining simulated sensor measurements with real measurements of mobile devices.Results show complex events can be detected in near real time(less than 1 s).

The association of Triatoma maculata(Ericsson 1848) with the gecko Thecadactylus rapicauda(Houttuyn 1782)(Reptilia:Squamata:Gekkonidae):a strategy of domiciliation of the Chagas disease peridomestic vector in Venezuela?

Objective:To investigate the bioecological relationship between Chagas disease peridomestic vectors and reptiles as source of feeding.Methods:In a three-story building,triatomines were captured by direct search and electric vacuum cleaner search in and outside the building.Then,age structure of the captured Triatoma maculata(T.maculata) were identified and recorded.Reptiles living in sympatric with the triatomines were also searched.Results:T.maculata were found living sympatric with geckos(Thecadactylus rapicauda) and they bit residents of the apartment building in study.A total of 1 448 individuals of T.maculata were captured within three days,of which 74.2%(1 074 eggs) were eggs,21.5%were nymphs at different stages,and 4.3%were adults.Conclusions:The association of T.maculata and T.rapicauda is an effective strategy of colonizing dwellings located in the vicinity of the habitat where both species are present;and therefore,could have implications of high importance in the intradomiciliary transmission of Chagas disease.

Mathematical Modeling of Hydrogels Swelling Based on the Finite Element Method

In recent years, hydrogels have been introduced as new materials suitable for applications in areas such as biomedical engineering, agriculture, etc. The rate and degree of hydrogel swelling are important parameters that control the diffusion of drugs or solvents inside a polymer network. Therefore, the description of the dynamic swelling process of the hydrogels is very important in applications that require precise control of the absorption of solvents inside the hydrogel structure. To date, most of the numerical models developed for describing the swelling process are based in the finite difference methods. Even though numerical models supported in finite differences can be easily implemented, their use is limited to samples with very simple shapes. In this paper, a new model based on the finite element method is proposed. The diffusion equation is solved in a time-deformable grid. An original procedure is proposed to numerically solve the non-linear algebraic equation system that permits computing a new grid for each time-step. Hydrogel samples of different shapes were prepared in order to conduct experimental tests to validate the numerical proposed model. Numerical results show that the new model is able to describe the mass and shape changes in the hydrogel samples in time. An application of the numerical model to determine the relation between diffusion coefficients and density in Poly-acrylamide samples allows verifying the versatility of the model.

Summary of Useful Concepts About the Coordination of Directional Overcurrent Protections

This paper summarizes some useful concepts about the coordination of directional overcurrent protections.The following key topics are described:the analysis of systems in a ring configuration and only one source of short-circuit currents;the impossibility of obtaining selectivity for all the possible system configurations with multiple sources;the need for inverse functions in order to obtain selectivity in systems with multiple sources;the coordination with protections for radial loads;the coordination between instantaneous and delayed functions;the considerations to select the pickup values;the influence of contributions from motors to short circuit currents;the transient configurations due to sequential trips at both line ends;the influence of dynamic behavior of overcurrent functions;the influence of stability constraints;other specific considerations for ground functions;some specific considerations for systems with distributed generation.A summary of these points and their effect on the coordination of directional overcurrent protections is not available in the current literature.This novel description should facilitate the inclusion of these key points in research and coordination studies related to these protective functions.

Multiple Limit Cycles in an Immune System

The nonlinear oscillatory phenomenon has been observed in the system of immune response,which corresponds to the limit cycles in the mathematical models.We prove that the system simulating an immune response studied by Huang has at least three limit cycles in the system.The conditions for the multiple limit cycles are useful in analyzing the nonlinear oscillation in immune response.

An egg-shell bifunctional CeO_(2)-modified NiPd/Al_(2) O_(3) catalyst for petrochemical processes involving selective hydrogenation and hydroisomerization

The catalytic performance during the 1-butyne hydrogenation using two reduced Al_(2) O_(3)-supported Pdbased catalysts was carried out in a total recirculation system with an external fixed-bed reactor.The lab-prepared egg-shell NiPd/CeO_(2)-Al_(2) O_(3) catalyst(NiPdCe) with Pd loading=0.5 wt%,Ni/Pd atomic ratio=1 and CeO_(2) loading=3 wt% was synthesized and characterized,and it was compared with an egg-shell Al_(2) O_(3)-supported Pd based commercial catalyst(PdCC).The reduced catalysts were characterized by X-ray diffraction,X-ray photoelectron spectroscopy,and high-resolution transmission electron microscopy.The textural characteristics and ammonia temperature-programmed desorption profiles of the fresh(unreduced) catalysts were also obtained.Both catalysts show high 1-butyne conversion and selectivity to 1-butene,but the catalysts also present important differences between hydroisomerizing and hydrogenating capabilities.NiPdCe catalyst shows higher capability for hydroisomerization reactions,while the PdCC catalyst exhibits higher hydrogenating capability.The observed catalytic performances can be interesting for some industrial processes and can provide a guideline for the development of a Pd-based catalyst with specific catalytic properties.