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MAX phase Ti2 Al(1− x) Sn x C solid solution with x = 0, 0.32, 0.57, 0.82, and 1 was synthesized by pressureless sintering of uniaxially pressed Ti, Al, Sn, and TiC powder mixtures. Annealing in air atmosphere at 200°C-1000°C triggered a sequence of oxidation reactions which reveal a distinct influence of solid solution composition on the oxidation process. With decreasing Al/ Sn ratio, the characteristic temperature of accelerated oxidation reaction of A-element was reduced from 900°C ( x = 0) to 460°C ( x = 1). SnO2 was formed at temperatures significantly lower than TiO2 (rutile) and Al2 O3. Substitution of A-element in MAX phase solid solution by low-melting elements such as Sn may offer potential for reducing oxidation-induced crack healing temperatures. [ABSTRACT FROM AUTHOR]

This work reports the oxidation and crack healing behavior of a fine-grained (~2 μm) Cr2 AlC MAX phase ceramic. The oxidation behavior was investigated in the temperature range 900°C-1200°C for times up to 100 h. The material showed a good oxidation resistance, owing to the formation of a dense and thin α- Al2 O3 layer. The microstructure, composition and thickness of the oxide scale were characterized. Its oxidative crack healing behavior as a function of temperature, healing time, and initial crack size was studied systematically. The material showed excellent healing behavior. The main crack healing mechanism is the filling of the crack by oxides well adhering to the crack faces. The crack geometry before and after healing was characterized by X-ray tomography. Three-point bend tests showed the dependence of strength recovery at 1100°C as a function of initial crack length and healing time. [ABSTRACT FROM AUTHOR]

Niobium aluminum carbide ( Nb4 AlC3), as a member of the MAX phases, can retain its stiffness and strength up to over 1400°C, however, the strength at room temperature is relatively low. In this work, Nb5( Si, Al)3 was used to strengthen Nb4 AlC3. Nb4 AlC3- Nb5( Si, Al)3 composites with different amount of Nb5( Si, Al)3 were synthesized from the elemental powders by in situ hot-pressing/solid-liquid reaction synthesis process. The RT flexural strength was significantly improved from 370 MPa of monolithic Nb4 AlC3 to 432 MPa of Nb4 AlC3-15 vol% Nb5( Si, Al)3 composite without the degradation of its high-temperature mechanical properties. While a slightly decrease in fracture toughness occurs with the increment of Nb5( Si, Al)3 content. Meanwhile, Transmission electron microscopy ( TEM) observations reveal that the interfaces between Nb4 AlC3/ Nb4 AlC3, Nb4 AlC3/ Nb5( Si, Al)3, and Nb5( Si, Al)3/ Nb5( Si, Al)3 are free of amorphous layers, which is also beneficial to its high-temperature mechanical properties. [ABSTRACT FROM AUTHOR]

In this study, we report on the compressive behavior of Ti3 AlC2 and Ti3 Al0.8 Sn0.2 C2 MAX phases at room temperature. We found that these two phases could be classified as Kinking Nonlinear Elastic (KNE) solids. The cyclic compressive stress-strain loops for Ti3 AlC2 and Ti3 Al0.8 Sn0.2 C2 are typical hysteretic and fully reversible. At failure, both compositions fracture in shear with maximum stresses of 545 MPa for Ti3 AlC2 and 839 MPa for Ti3 Al0.8 Sn0.2 C2. Consequently, the macroshear stresses for failure, τc, are 185 MPa and 242 MPa for Ti3 AlC2 and Ti3 Al0.8 Sn0.2 C2, respectively. In addition to the grain size effects, the presence of a ductile Ti x Al y intermetallic distributed in the grain boundaries plays an important role in the enhancement of the ultimate compressive and macroshear stresses for Ti3 Al0.8 Sn0.2 C2. SEM observations reveal that these two MAX phases exhibit crack deflections, intragranular fractures, kink band formation and delaminations, grain push-in and pull-out. [ABSTRACT FROM AUTHOR]

Using spark plasma sintering, Ti3 AlC2/ W composites were prepared at 1300°C. They contained 'core-shell' microstructures in which a Ti xW1− x 'shell' surrounded a W 'core', in a Ti3 AlC2 matrix. The composite hardness increased with W addition, and the hardening effect is likely achieved by the Ti x W1− x interfacial layer providing strong bonding between Ti3 AlC2 and W, and by the presence of hard W. Microstructural development during high-temperature oxidation of Ti3 AlC2/ W composites involves α- Al2 O3 and rutile ( TiO2) formation ≥1000°C and Al2 TiO5 formation at ~1400°C while tungsten oxides appear to have volatilized above 800°C. Likely due to exaggerated, secondary grain growth of TiO2-doped alumina and the effect of W addition, fine (<1 μm) Al2 O3 grains formed dense, anisomorphic laths on Ti3 AlC2/5 wt% W surfaces ≥1200°C and coarsened to large (>5 μm), dense, TiO2-doped Al2 O3 clusters on Ti3 AlC2/10 wt% W surfaces ≥1400°C. W potentially affects the oxidation behavior of Ti3 AlC2/ W composites beneficially by causing formation of Ti x W1− x thus altering the defect structure of Ti3 AlC2, resulting in Al having a higher activity and by changing the scale morphology by forming dense Al2 O3 laths in a thinner oxide coating, and detrimentally through release of volatile tungsten oxides generating cavities in the oxide scale. For Ti3 AlC2/5 wt% W oxidation, the former beneficial effects appear to dominate over the latter detrimental effect. [ABSTRACT FROM AUTHOR]

We evaluated the effects of sperm concentration, progressive motility, sperm morphology, duration of abstinence and collection season on the progressive motility recovery rate of human frozen spermatozoa to identify characteristics that predict the progressive motility recovery rate of human frozen spermatozoa and improve the protocol for sperm collecting in sperm banks. A total of 14 190 semen samples donated at Zhejiang human sperm bank of China between September 2006 and June 2011 were collected from 1624 donors. Semen was evaluated according to WHO standard procedures for sperm concentration. Progressive motility, sperm morphology, ejaculate collection season and abstinence time were recorded. After freezing and thawing, the progressive motility was assessed. Results showed that sperm concentration, progressive motility and normal morphology were significantly associated with the progressive motility recovery rate of human frozen spermatozoa. In addition, the abstinence time and collection season also significantly affected progressive motility recovery rate. Our results indicated that sperm concentration, progressive motility and normal morphology could be valuable in predicting the progressive motility recovery rate of human frozen spermatozoa. As such, progressive motility recovery may be improved by donating semen when abstinent for 3-5 days and during seasons other than summer. [ABSTRACT FROM AUTHOR]

Solid solution composites of ( Ti, V)2 AlC/ Al2 O3 were successfully synthesized using the in situ hot-pressing process by the incorporation of the thermit reaction of Al with V2 O5 in Ti, Al, and carbon black system. The phase evolution during the formation of the composites was examined from 500°C to 1350°C, and a possible reaction mechanism was proposed to explain the formation of ( Ti, V)2 AlC/ Al2 O3 solid solution composites. The composite with 10 wt% Al2 O3 possesses the best mechanical properties and the hardness, flexural strength, and fracture toughness of the composites are enhanced by 53.2%, 140%, and 180%, respectively. The strengthening and toughening mechanisms were also discussed. [ABSTRACT FROM AUTHOR]

A coating of Ti-C:H was investigated for potential applications as artificial joint materials. Herein, we conducted experimental study using fluid shear method and tribolgoical study to evaluate and analyze the adhesive strength of proteins on Ti-C:H coatings and Ti6Al4V. Sample surfaces were worn against a steel bearing (E52100) under the lubrication of egg white protein solution. The following wear track and debris analysis helped further understand their wear mechanism. Research results showed that Ti-C:H coatings on silicon substrate had a porous topography that enhanced its adhesion with the protein. The friction coefficient and wear rate for Ti-C:H was much lower than Ti6Al4V. This can be attributed to the chemical inertness and functional diamond-like features of Ti-C:H coatings enhancement in wear resistance, making it superior to Ti6Al4V. [ABSTRACT FROM AUTHOR]

In this study,we have shown the applicability of electrophoretic deposition ( EPD) for shape-forming in Ti3 SiC2-a representative MAX phase; and viability of texture development thereof by application of a strong magnetic field (12 T). The dispersion characteristics of Ti3 SiC2 suspension were investigated in terms of surface charge, rheological measurement, and adsorption study. Polyethyleneimine has been used as dispersant to stabilize the suspension. It was found that the iso-electric point ( IEP) of Ti3 SiC2 powder was pHIEP ~ 4. The surface charge of powder changed in presence of the Polyethyleneimine dispersant and IEP shifted significantly towards basic pH ~ 10. The shift in IEP has been quantified in terms of Δ G0SP, the specific free energy of adsorption between the surface sites and the adsorbing polyelectrolyte ( PEI) (The value of Δ G0SP obtained is −9.521 RT units). The optimized suspension parameters for EPD were determined as 10 vol% Ti3 SiC2 and 1 dwb PEI in 50% ethanolic water at pH ~ 7. X-ray diffraction analysis of the textured samples developed, revealed that the preferred orientation of Ti3 SiC2 grains parallel to the magnetic field direction was along the a, b-axis (The Lotgering orientation factors on the textured top surface and textured side surface were determined as fL( hk0) = 0.35 and fL(00 l) = 0.75, respectively). [ABSTRACT FROM AUTHOR]

This study was designed to evaluate the effects of semen processing on the generation of intracellular reactive oxygen species (ROS) and mitochondrial membrane potential (MMP) in spermatozoa, and to develop reliable indexes for the evaluation of sperm quality during sperm preparation. Swim-up and density gradient centrifugation methods were used to separate semen in oligoasthenoteratozoospermia (OAT), leucocytospermia (LC) and normozoospermia groups. Levels of ROS and MMP were measured by flow cytometry. Before preparation, the patients with abnormal semen parameters had a lower MMP and higher ROS, and there was a negative correlation between MMP and ROS. The levels of MMP and ROS increased significantly, especially ROS produced by swim-up. A significant difference was found between the correlation of MMP and total normal motile sperm count after preparation in the OAT group. The level of ROS was associated with the amount of white blood cells in the LC group. The MMP can be used as an objective index to evaluate the sperm quality of OAT patients, and the combination of MMP and ROS can be used to assess the efficiency of sperm preparation in LC patients. These findings can guide selection of the ideal sperm separation technique for different sperm samples. [ABSTRACT FROM AUTHOR]

Summary Interleukin-10 (IL-10) is a cytokine with anti-inflammatory and B-cell-stimulating activity. IL-10 is expressed in human atherosclerotic plaques and studies have shown the involvement of IL-10 in the atherosclerotic process. The IL-10−1082G/A polymorphism is one of the most commonly studied polymorphisms in this gene because of its association with coronary heart disease (CHD) risks, but previous results have been conflicting. We performed a meta-analysis using six eligible case-control studies (including 14 data sets) with a total of 5006 patients and 3968 controls to summarize the existing data on the association between the IL-10−1082G/A polymorphism and CHD risk. Compared with the common IL-10−1082G/A GG genotype, the carriers of variant genotypes ( IL-10−1082GA/AA) had a 1.12-fold elevated risk of CHD (95% CI = 1.01-1.23, P = 0.03) under the dominant genetic model, as estimated using a random effect model. The effect of the IL-10−1082G/A polymorphism was further evaluated using stratification analysis. In the three disease of artery studies, with the variant genotypes had a not obvious increased risk of disease of artery (OR = 1.19, 95% CI = 0.98-1.44, P = 0.08) as estimated using a fixed effect model. Similar results were found in the nine myocardial infarction studies (OR = 1.13, 95% CI = 1.00-1.27, P = 0.05). It was also demonstrated that the increased risk of CHD associated with IL-10−1082G/A variant genotypes was more pronounced in Caucasians (OR = 1.12, 95% CI = 1.01-1.23, P = 0.03). Our meta-analysis suggests that the IL-10−1082G/A polymorphism genotypes (GA+AA) might be associated with an increased risk of CHD, especially in Caucasians. [ABSTRACT FROM AUTHOR]

Herein we report on the formation of a Ti-C-O-F phase via the topotactic transformation of Ti2AlC by immersion in molten lithium fluoride, LiF, at 900°C in air for 2 h. The Al diffuses out of the structure and reacts with LiF to form Li3AlF6. X-ray diffraction, Raman spectroscopy, optical, scanning and transmission electron microscopy, with energy-dispersive spectroscopy, showed the selective etching of Al from the structure and the formation of a cubic, rock-salt, Ti-C-O-F phase. The transformation is topotaxial, involves de-twinning of the hexagonal Ti2AlC structure and results in domains that are of the order of 10 nm. The reaction rate is significantly higher when the reaction is carried out in air than when it is carried out in vacuum. [ABSTRACT FROM AUTHOR]

Mesosporous carbon-bonded titanium-carbide/silicon-carbide ( C-TiC/SiC) ceramics with a high specific surface area (221 m2/g), ultra fine grains (10-50 nm), and high crystallinity were synthesized from direct carbothermal reduction (1100°-1450°C) of monolithic Ti-Si-O-C precursors made from controlled sol-gel process. The nano-sized carbide grains are bonded into bulk materials by poly(furfuryl alcohol) ( PFA) derived nanocrystalline carbon framework by 'bridge,' 'entanglement,' and 'adhesive' effects. Graphenes were found to grow on {111} planes of TiC grains but this was not observed for SiC. The bonding of graphitic carbon layers on carbide grains support the nanostructure and also result in the desired combination of functional and mechanical properties. [ABSTRACT FROM AUTHOR]

In this article, the reactivity of Ti2AlC powders, with 3 and 10 μm alumina, Al2O3, fibers during pressure-assisted sintering is explored. Samples were fabricated by hot-isostatic-pressing ( HIPed) or hot-pressing ( HPed), and characterized by X-ray diffraction, differential thermal analysis, and electron microscopy-both scanning and transmission-equipped with energy dispersive X-ray spectroscopes. Samples prepared at 1300°C were fully dense, with no apparent reaction between fiber and matrix. In samples HPed to 1500°C, even pure Ti2AlC powders dissociated to Ti3AlC2 according to: 2 Ti2AlC = Ti3AlC2 + TiAl x ( l) + (1- x) Al ( l/ v), with x < 1. More severe Al loss results in the formation of TiC y. The presence of the Al2O3 fibers delayed densification enough to allow most of the Al and some of the Ti to escape into the vacuum of the hot press or react with the encapsulating glass during HIPing a resulting in a more intensive dissociation of the Ti2AlC. Although, in principle Ti2AlC can be reinforced with Al2O3 fibers, the processing/use temperature will have to be kept below 1500°C, as, at that temperature the fibers, used here, sinter together. [ABSTRACT FROM AUTHOR]

In this work, we report on the temperature-dependent crystal structures of the isostructural, layered hexagonal phases Ti2AlN and Cr2GeC determined by Rietveld analysis of high temperature neutron powder diffraction data of fully dense, polycrystalline, bulk samples in the 100° to 1100°C temperature range. For both phases, the A-group atoms, Al and Ge, vibrate with the highest amplitude and do so anisotropically within the basal plane. All bonds expand linearly with temperature, with the highest relative thermal expansion occurring in the Ti-Al and Cr-Ge bonds. The thermal expansion coefficients in the a- and c-direction are, respectively, 10.3(±0.2) × 10−6 and 9.3(±0.2) × 10−6 K−1 for Ti2AlN and 12.8(±0.3) × 10−6 and 14.6(±0.3) × 10−6 K−1 for Cr2GeC. The unit cell volume expansions observed by HTND are 10.0(±0.2) × 10−6 K−1 for Ti2AlN and 13.4(±0.3) × 10−6 K−1 for Cr2GeC. [ABSTRACT FROM AUTHOR]

The aim of this investigation was to determine whether tumour necrosis factor-alpha (TNF-α) has any effect on endothelial progenitor cells (EPCs). Total mononuclear cells were isolated from peripheral blood by Ficoll density gradient centrifugation, and then the cells were plated on fibronectin-coated culture dishes. After 7 days culture, attached cells were stimulated with tumour necrosis factor-α (final concentrations: 0, 10, 20, 50 and 100 mg/l) for 0, 6, 12, 24 and 48 h. EPCs were characterized as adherent cells double positive for DiLDL-uptake and lectin binding, by direct fluorescence staining. EPC proliferation and migration were assayed using the MTT assay and modified Boyden chamber assay, respectively. EPC adhesion assay was performed by re-plating those cells on fibronectin-coated dishes, and adherent cells were counted. Tube formation activity was assayed using a tube formation kit. Levels of apoptosis were revealed using an annexin V apoptosis detection kit. Vascular endothelial growth factor Receptor-1 (VEGF-R1) and stromal derived factor-1 (SDF-1) mRNA, assessed by real-time RT-PCR inducible nitric oxide synthase (iNOS) and endothelial nitric oxide synthase (eNOS) were assayed by western blot analysis. Incubation of EPCs with tumour necrosis factor-α reduced EPC proliferation, migration, adhesion, tube formation capacity, iNOS and eNOS in concentration- and time-dependent manners. Tumour necrosis factor-α reduced proliferation, migration, adhesion and tube formation capacity of EPCs. TNF-α increased EPC apoptosis level, reduced VEGF-R1 and SDF-1 mRNA expression; tumour necrosis factor-α also reduced iNOS and eNOS in the EPCs. [ABSTRACT FROM AUTHOR]

Nb-doped Zr2[Al(Si)]4C5 solid solutions were prepared by in situ hot pressing method and their high-temperature oxidation behavior at 1000°-1300°C were investigated. The oxidation resistance of [Zr0.9(Nb0.1)]2[Al(Si)]4C5 solid solutions is improved remarkably compared with Zr2[Al(Si)]4C5 without dopant. The improved oxidation resistance is due to the formation of a more protective oxide scale consisting of (Zr,Nb)O2, Nb2 Zr6O17, Al2O3, and mullite, in which (Zr,Nb)O2 solid solution is more effective than ZrO2 in depressing the inward diffusion of oxygen. In addition, the decrease of cracks in the oxide scale above 1100°C in Nb-doped sample is also beneficial to the improved oxidation resistance. [ABSTRACT FROM AUTHOR]

The aim of this study was to explore the relationship between early childhood caries (ECC) and relevant socio-economic, behavioural and biological experiences in the life course of children. A cross-sectional study of 2-year-old children was analysed. A questionnaire collected socio-economic and behavioural data during the first two years of the participants' life. Caries experience was recorded at the level of cavitation and oral hygiene was assessed using the Visible Plaque Index (VPI). Microbiological investigation collected information on colony-forming units (CFU) of Streptococcus mutans ( S. mutans). The outcome was ECC. Bivariate and multiple logistic regression analyses were performed. The study included 394 children, with 109 having ECC and 285 being caries-free. The mean decayed, missing and filled primary teeth (dmft) score of the ECC group was 3.65 ± 3.12, with decayed teeth making up 100% of the score. The results of the final logistic regression analysis showed that ECC was significantly associated with the mother's schooling at child's birth [<12 years vs. ≥12 years, OR = 1.80], VPI score [>60% vs. 0-20%, OR = 5.71], and S. mutans [≥10CFU/ml vs. 0 CFU/ml, OR = 3.80]. Social, behavioural and biological factors during the life course of 2-year-old children in southern China are associated with the development of ECC. [ABSTRACT FROM AUTHOR]

Background and Purpose: Caffeine is consumed extensively in Europe and North America. As a risk factor for osteoporosis, epidemiological studies have observed that caffeine can decrease bone mineral density, adversely affect calcium absorption and increase the risk of bone fracture. However, the exact mechanisms have not been fully investigated. Here, we examined the effects of caffeine on the viability and osteogenesis of rat bone marrow-derived mesenchymal stromal cells (rBMSCs).Experimental Approach: Cell viability, apoptosis and necrosis were quantified using thymidine incorporation and flow cytometry. Sequential gene expressions in osteogenic process were measured by real-time PCR. cAMP, alkaline phosphatase and osteocalcin were assessed by immunoassay, spectrophotometry and radioimmunoassay, respectively. Mineralization was determined by calcium deposition.Key Results: After treating BMSCs with high caffeine concentrations (0.1-1mM), their viability decreased in a concentration-dependent manner. This cell death was primarily due to necrosis and, to a small extent, apoptosis. Genes and protein sequentially expressed in osteogenesis, including Cbfa1/Runx2, collagen I, alkaline phosphatase and its protein, were significantly downregulated except for osteocalcin and its protein. Moreover, caffeine inhibited calcium deposition in a concentration- and time-dependent manner, but increased intracellular cAMP in a concentration-dependent manner.Conclusions and Implications: By suppressing the commitment of BMSCs to the osteogenic lineage and selectively inhibiting gene expression, caffeine downregulated some important events in osteogenesis and ultimately affected bone mass. [ABSTRACT FROM AUTHOR]

Xiong F, Sun M, Zhang X, Cai R, Zhou Y, Lou J, Zeng L, Sun Q, Xiao Q, Shang X, Wei X, Zhang T, Chen P, Xu X. Molecular epidemiological survey of haemoglobinopathies in the Guangxi Zhuang Autonomous Region of southern China. Accurate and up-to-date data on the frequency of haemoglobinopathies among the populations of Guangxi Zhuang Autonomous Region, where haemoglobinopathies are most endemic in China, are required. In our study, a total of 5789 samples obtained from members of the Han, Zhang, and Yao ethnic groups in six geographical areas of Guangxi Province were analysed systematically in terms of both haematological and molecular parameters. The results presented that the total heterozygote frequency of thalassaemias and other haemoglobinopathies was 24.51%, of which 17.55% was due to α-thalassaemia, 6.43% to β-thalassaemia, 0.38% to structural haemoglobin variants, and 0.16% to δ-thalassaemia. The mutational spectrum among the local population for each type of disorder was described, including the first report on the true prevalence of three silent α thalassemia defects, −α3.7/(4.78%), −α4.2/(1.61%) and Hb Westmead (αWSα/) (1.57%) and of δ-thalassemia resulting from five novel and two rare mutations never before identified in Chinese individuals. Comparison of the frequencies of α-globin mutations among the ethnic groups showed that there was a statistically significant difference between the Han (15.71%) and Zhuang (20.12%), and between the Han (15.71%) and Yao (20.84%) ethnic groups. In addition, we have performed the first extensive study of haematological parameters of the Hb Westmead mutation using a group of Chinese subjects with compound heterozygosity for this variant and an α-thalassaemia deletion. The knowledge gained in this study will enable us to estimate the health burden in this high-risk population and to elucidate the various genetic alterations that underlie haemoglobinopathies. [ABSTRACT FROM AUTHOR]

Hard materials used in such abrasive wear applications as cutting tools and wear inserts in drilling tools require high hardness to resist wear, high fracture toughness to withstand mechanical and thermal shock, and high chemical and thermal stability. Such a combination of properties is difficult to achieve in single-phase materials. Functional grading is an approach that overcomes this limitation by designing and processing a graded microstructure that provides high hardness and chemical resistance at the surface with a tough interior or bulk. While functional grading is a widely used practice in the cemented carbides industry, it has not been demonstrated with 'pure' carbides. This article reports the feasibility of designing and processing a graded carbide in the Ta-C binary system. It is shown that a simple carburization treatment of the high-toughness carbide, ζ-Ta4C3− x, can lead to the formation of the hard carbide phase, γ-TaC y, on the surface. The thickness, microstructure (grain size), and composition (C/Ta atomic ratio, y) of the γ-TaC y layer can be optimized to obtain both high hardness and high strength for the graded material. [ABSTRACT FROM AUTHOR]

The article describes the case of a female Pomeranian dog with a vitamin D receptor (VDR) gene mutation resulting in hereditay vitamin D-resistant rickets (HVDRR), which is attributable to a 1 bp deletion in exon 4 and a premature stop in exon 5. The dog was examined for alopecia and abnormal forelimb conformation, which upon further tests confirmed the presence of persistent hypocalcemia and diffuse forebrain disease. Genetic analyses of the dog revealed HVDRR due to VDR mutation.

BCSC-1 is dramatically upregulated in CNE-2L2 human nasopharyngeal carcinoma cells with reduced malignancy (AS cells) and is proposed to be a candidate tumor suppressor gene. We therefore examined the effect of BCSC-1 expression on malignant behaviors of CNE-2L2 cells. Growth in vitro and tumorigenesis in nude mice of wild-type CNE-2L2 cells (W cells) were inhibited by ectopic BCSC-1, and those of AS cells were promoted by BCSC-1 suppression. The tumor suppressor function of BCSC-1 was further confirmed by a study showing that intratumor BCSC-1 injection caused growth suppression of the tumor from W cells inoculated in nude mice. Immunohistochemistry exhibited marked reduction of BCSC-1 expression in 11 of 39 human nasopharyngeal carcinoma specimens. Because BCSC-1 expression was as rich as that in normal cells in the rest of the carcinoma specimens and was poor in CNE-2L2 cells, HNE-1 human nasopharyngeal carcinoma cells with rich BCSC-1 expression were used as a control in the study. No effect of BCSC-1 transfection on growth of the cells was observed. The data suggest that BCSC-1 suppression might play roles in tumorigenesis of some nasopharyngeal carcinomas and that BCSC-1 might be a potential gene therapy target in nasopharyngeal carcinomas with poor BCSC-1 expression. Enhanced aggregation of cells together with increased E-cadherin and α-catenin expression and reduced Wnt signaling might be involved in the mechanisms of tumor suppressor function of BCSC-1. ( Cancer Sci 2009; 100: 1817–1822) [ABSTRACT FROM AUTHOR]

The article presents a prospective study that combines maternal age, fetal nuchal translucency (NT) and maternal serum freeβ-human chorionic gonadotropin (β-hCG) , and pregnancy-associated plasma protein-A (PAPP-A) in screening for trisomy 21. It presents the characteristics of 19, 614 pregnancies with normal delivery and 122 cases of trisomy 21, which comprise the study population. It reveals that the capability of the combine method to detect 90% for trisomy 21.

The article presents a study that examines the deviations effect of median nuchal translucency thickness (NT) measurements on the screening performance in trisomy 21. The said deviations were investigated by simulation of NT and multiples of the median (MoM) values at given gestation weeks. It shows that little deviations in median NT do not have an effect on the screening performance and would not benefit from the operator-specific medians use, which makes the entire screening method complex.

Knowledge of the cardiac safety of emerging new drugs is an important aspect of assuring the expeditious advancement of the best candidates targeted at unmet medical needs while also assuring the safety of clinical trial subjects or patients. Present methodologies for assessing drug-induced torsades de pointes (TdP) are woefully inadequate in terms of their specificity to select pharmaceutical agents, which are human arrhythmia toxicants. Thus, the critical challenge in the pharmaceutical industry today is to identify experimental models, composite strategies, or biomarkers of cardiac risk that can distinguish a drug, which prolongs cardiac ventricular repolarization, but is not proarrhythmic, from one that prolongs the QT interval and leads to TdP. To that end, the HESI Proarrhythmia Models Project Committee recognized that there was little practical understanding of the relationship between drug effects on cardiac ventricular repolarization and the rare clinical event of TdP. It was on that basis that a workshop was convened in Virginia, USA at which four topics were introduced by invited subject matter experts in the following fields: Molecular and Cellular Biology Underlying TdP, Dynamics of Periodicity, Models of TdP Proarrhythmia, and Key Considerations for Demonstrating Utility of Pre-Clinical Models. Contained in this special issue of the British Journal of Pharmacology are reports from each of the presenters that set out the background and key areas of discussion in each of these topic areas. Based on this information, the scientific community is encouraged to consider the ideas advanced in this workshop and to contribute to these important areas of investigations over the next several years. [ABSTRACT FROM AUTHOR]

In this study, a well-dispersed γ-Y2Si2O7 ethanol-based suspension with 30 vol% solid loading was prepared by adding 1 dwb% polyethylene imine dispersant, which allows feeble magnetic γ-Y2Si2O7 particles with anisotropic magnetic susceptibility to rotate in a 12 T strong magnetic field during slip casting, resulting in the development of a strong texture in green bodies. Pressureless sintering gives rise to more pronounced grain growth in the textured sample than in the untextured sample prepared without the magnetic field due to the rapid migration of the grain boundaries of the well-oriented grains, which was revealed by constant-heating-rate sintering kinetics. It was found that the use of two-step sintering is very efficient not only for inhibiting the grain growth but also for enhancing the texture. This implies that controlled grain growth is crucial for enhancing texture development in γ-Y2Si2O7. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To identify the genetic abnormality responsible for osteoarthritis (OA), avascular necrosis (AVN) of the femoral head, and Legg-Calvé-Perthes disease in a single family, and to determine factors responsible for the distinct phenotypes manifested by different family members. METHODS: Forty-two members of a 5-generation family were recruited and investigated. Diagnosis was made by independent orthopedic surgeons and radiologists. Histopathologic changes of the diseased tissue were examined. Linkage analysis was performed with markers spanning the COL2A1 locus. Haplotypes were constructed and mutation of the gene was detected. Structures of the wild-type and mutant proteins were modeled. RESULTS: Sixteen affected members were identified (5 with isolated precocious hip OA, 6 with AVN of the femoral head, and 5 with Legg-Calvé-Perthes disease). A p.Gly1170Ser mutation of COL2A1 cosegregated with the 3 diseases and was absent in controls. Of note, age at onset in relation to the closure status of the femoral head epiphysis was associated with the diseases, with Legg-Calvé-Perthes disease presenting prior to closure (at ages 6-14 years), AVN of the femoral head presenting during closure (at ages 15-18 years), and precocious OA of the hip presenting after closure (at ages 21-34 years). Molecular modeling predicted that the serine-to-glycine substitution loosens the helical structure of the protein. CONCLUSION: The p.Gly1170Ser mutation of COL2A1 in the family described is responsible for pathology confined to the hip joint, which presents as isolated precocious hip OA, AVN of the femoral head, or Legg-Calvé-Perthes disease. Age at onset in relation to closure of the femoral head epiphysis appears to be a critical factor in determining disease pattern. [ABSTRACT FROM AUTHOR]

Background and Purpose: Ischaemia damages to the cardiac mitochondria by increasing generation of reactive oxygen species (ROS) and peroxidation of cardiolipin. The inhibited mitochondrial function leads to the cardiac injury during reperfusion. Propofol (2, 6-diisopropylphenol), an intravenous anaesthetic, has been shown to decrease cardiac ischaemia and reperfusion injury. In the present study, we propose that propofol protects mitochondrial function and decreases cardiac injury by prevention of cardiolipin peroxidation during ischaemia and reperfusion.Experimental Approach: After isolation of mitochondria from isolated rat heart perfused on a Langendorff model, various mitochondrial bioenergetic parameters were evaluated such as rates of mitochondrial oxygen consumption, H(2)O(2) production, complex I and III activity as well as the degree of lipid peroxidation and cardiolipin content. The action of propofol was also explored in isolated mitochondria. And the effect of cardiolipin was evaluated by fusing cardiolipin liposome with mitochondria.Key Results: Propofol treatment had strong dose-dependent protection attenuating these parameters alterations in reperfused rat heart and isolated mitochondria. Additionally, cardiolipin treatment had the same protective effect, compared with propofol treatment at high concentration.Conclusions and Implications: The protective effect of propofol appears to be due, at least in part, as a chemical uncoupler, to the interruption of the vicious circle of ROS-cardiolipin-complexes of the respiratory chain-ROS through preserving the content and integrity of cardiolipin molecules by ROS attack. These findings may provide an explanation for some of the factors responsible for cardioprotection and one approach exploring an available antioxidant. [ABSTRACT FROM AUTHOR]

Ti3SiC2 has many salient properties including low density, high strength and modulus, damage tolerance at room temperature, good machinablity, and being resistant to thermal shock and oxidation below 1100°C. However, the low hardness and poor oxidation resistance above 1100°C limit the application of this material. The poor oxidation resistance at temperatures above 1100°C was because of the absence of protective layer in the scale and the presence of TiC impurity phase. TiC impurity could be eliminated by adding a small amount of Al to form Ti3Si(Al)C2 solid solutions. Although the high-temperature oxidation resistance was significantly improved for the Ti3Si(Al)C2 solid solutions, the strength at high temperatures was lost. One important way to enhance the high-temperature strength is to incorporate hard ceramic particles like SiC. In this article, we describe the in situ synthesis and simultaneous densification of Ti3Si(Al)C2/SiC composites using Ti, Si, Al, and graphite powders as the initial materials. The effect of SiC content on high-temperature mechanical properties and oxidation resistance were investigated. The mechanisms for the improved high-temperature properties are discussed. [ABSTRACT FROM AUTHOR]

Eight cases with a histological diagnosis of primary breast lymphoma between April 2013 and Feb 2019 were identified and the clinical features and imaging findings on sonography were investigated. One patient had a small lymphocytic B-cell lymphoma(1/8, 20%), and two had a Burkitt-like high-grade B-cell lymphoma (2/8, 25%). Some imaging features may alert the diagnosis of primary breast lymphoma, but final diagnosis depends on histopathology. [Extracted from the article]

To investigate the clinical pathological features and ultrasound findings in 6 patients with primary non-Hodgkin's lymphoma (NHL) of the female reproductive system. A retrospectively analysis was performed on the clinical date of 6 patients with primary (NHL) of the female reproductive system from May 2013 to Feb 2019. Here were 8 lesions of the six patients which were detected by ultrasound. [Extracted from the article]

Worldwide, 5%-10% of infertility patients have FGTB. 24 infertile women with a pathological diagnosis of FGTB between April 2013 and Feb 2019 were identified and the clinical features and findings on transvaginal sonography (TVS) were investigated. Endometrial TB was pathological diagnosed in 15 women, the sonographic features were as follows: intrauterine adhesions 46.67% (7/15), endometrial polyps 13.33% (2/15), heterogeneous endometrium with subendometrial calcification 13.33% (2/15), and normal 26.67% (4/15). [Extracted from the article]

OBJECTIVE: The precipitating event(s) that triggers Wegener's granulomatosis (WG) is unknown. Cytokines, costimulatory molecules, and counterregulatory molecules control the quality and intensity of immune responses. Thus, they are relevant candidates for genetic studies of immune dysregulation in WG, the pathogenesis of which may be facilitated by multiple acquired and/or inherited factors. This study was undertaken to investigate possible genetic associations of various proinflammatory cytokines and CTLA-4, a receptor for T cell inhibition, with WG. METHODS: Using polymerase chain reaction-based DNA genotyping, we investigated the polymorphisms located in the genes encoding a variety of proinflammatory cytokines and CTLA-4 in 117 American patients with WG and 123 ethnically matched healthy controls. RESULTS: Compared with controls, patients with WG had a significantly lower frequency of homozygosity for the shortest allele (designated allele 86) of the Ctla4 microsatellite polymorphism (AT)n located in the 3'-untranslated region (3'-UTR) of exon 3 (47.0% versus 69.9%; P = 0.0005). Significant differences between patients and controls in the allelic and genotypic frequencies of polymorphisms in the other cytokine and cytokine receptor genes studied (tumor necrosis factor alpha [TNFalpha], TNF receptor I [TNFRI], TNFRII, interleukin-1beta [IL-1beta], IL-6) were not found. CONCLUSION: The Ctla4 (AT)n 86 allele has been previously demonstrated to be crucial for maintenance of normal levels of CTLA-4 expression and balance between T cell activation and inhibition. Our results in American patients confirm findings from a Scandinavian cohort in which a positive association between WG and longer alleles of (AT)n in the Ctla4 3'-UTR was demonstrated. Diminished frequencies of the most effective allele for CTLA-4 expression may represent a WG-related susceptibility mutation that accounts, in part, for increased T cell activation and clonal expansion in WG. Blockade of T cell costimulation using CTLA-4Ig might be a useful therapeutic intervention, providing an alternative or complementary approach to conventional treatment with immunosuppressive agents. [ABSTRACT FROM AUTHOR]

Investigates the effects of stem canker and light leaf spot on yield of winter oilseed rape in southern England. Analysis on the relationship between yield loss and incidence or severity of stem canker; Combination of effects on several diseases on crop yield; Interaction between pests and diseases.

The article focuses on the effects of the resistance to failure under an oscillating load, fatigue, and constant load (CL) presented in linear polyethylenes. It says that the effects of fatigue and CL on brittle fracture are compared with the relative influence of the molecular structure such as the molecular weight and branching. It adds that the molecular weight has relatively greater influence on fatigue, while branching is significant under CL.

A polymerase chain reaction (PCR) method was used to detect the interleukin-2 receptor α-chain (IL-2Rα) chain which lacks the conventional transmembrane (TM) domain in mRNA from human T-cell leukaemia virus type-I (HTLV-I) -infected cell lines or peripheral blood mononuclear cells (PBMC) isolated from adult T-cell leukaemia (ATL) patients. Primer pairs encompassing the TM domain were selected to generate a 357-base pair (bp) fragment. A 146-bp PCR product was observed consistently in addition to the target 357-bp PCR product in mRNA from HTLVI-infected cell lines, such as MT-1, MT-2, MT-4 and in PBMC isolated from ATL patients. However, this 146-bp PCR product was undetectable in HTLV-1-negative cell lines. The product wan also detected in PBMC from normal individuals if activated in vitro with phytohaemagglutinin but not without stimulation. DNA sequence analyses revealed that exons from 5 to 7, which define a 211-bp region containing the conventional TM domain, were deleted in the 146-bp PCR product. The C-terminal amino acid sequence starting from Gly174 of the 211-bp-deleted molecule was distinct from that of conventional IL-2Rα as a result of an altered reading frame. We identified a 45 000 MW peptide generated from IL-2Rα mRNA through this exon skip in cell lysate of MT-1 and MT-2 by Western blot analyses using an antibody raised against the peptides specific to an altered IL-2Rα. Our results indicate that an altered IL-2Rα chain is expressed in HTLV-1-infected T lymphocytic cell lines and in ATL patients. [ABSTRACT FROM AUTHOR]

Electronic devices that can simulate the dynamics of neurotransmission in the human body are of great interest for the development of artificial intelligence in modern information technology. An artificial nociceptor realized by a single metal‐oxide nanobelt device with a unique capacitive‐coupled threshold switching behavior is demonstrated. Via thermal admittance spectroscopy and temperature‐dependent sweeping study, the properties of the nanobelt devices are determined by Schottky emission at low bias and by defect‐assisted quantum tunneling at high bias subject to a threshold voltage. The low activation energy associated with dynamic electron trapping gives rise to a voltage‐dependent volatile threshold switching behavior. This threshold switching behavior allows the emulation of several characteristic features of a nociceptor, a critical type of sensory neuron in the human body, including "threshold," "relaxation," "no adaptation," "allodynia," and "hyperalgesia" behaviors, essential for the realization of electronic sensory receptors that detect noxious stimuli and signal rapid warning to the central nervous system. One‐dimensional metal oxide nanobelt devices of this type yield multifunctional nociceptor performance that is fundamental for applications in artificial intelligence systems, representing a key step in the realization of neural integrated devices via a bottom‐up approach. [ABSTRACT FROM AUTHOR]

The cyst was multilocular in the right and unilocular in the left, both of the cysts were anechoic with smooth internal walls on B-mode imaging and no flow on colour Doppler imaging according to the International Ovarian Tumour Analysis definitions. Magnetic resonance imaging (MRI) revealed showing multiple T2 hyperintense masses of varying sizes along the serosal surfaces of the uterus and adnexa. A year later, the cysts gradually enlarged, and there were multiple cysts in the pelvic-abdominal cavity. [Extracted from the article]

Reports on the use of color Doppler ultrasound to diagnose placenta accreta in the first trimester of pregnancy. Disease background; Factors affecting the determination of variant forms of placenta accreta; Blood flow to intervillous space; Importance of early diagnosis.