Effects of ovarian hyperstimulation on mitochondria in oocytes and early embryos.

A mouse model was used to compare the number and function of mitochondria in oocytes and embryos obtained by superovulation and in a natural cycle (control group). The superovulation group had a higher number of total oocytes, MII oocytes, embryos with two pronuclei, 2-cell embryos and blastocysts than the control group (P<0.05 for all). The superovulation group had high proportion of MII oocytes with low number of mitochondrial (mt) DNA copies. The average number of mtDNA copies, ATP level and mitochondrial membrane potential (

A platform for soybean molecular breeding: the utilization of core collections for food security.

Soybean is an important crop not only for human consumption but also for its addition of nitrogen to the soil during crop rotation. China has the largest collection of cultivated soybeans (Glycine max) and wild soybeans (Glycine soja) all over the world. The platform of soybean core, mini core and integrated applied core collections has been developed in the past decade based on systematic researches which included the sampling strategies, statistical methods, phenotypic data and SSR markers. Meanwhile, intergrated applied core collections including accessions with single or integrated favorite traits are being developed in order to meet the demand of soybean breeding. These kinds of core collections provide powerful materials for evaluation of germplasm, identification of trait-specific accessions, gene discovery, allele mining, genomic study, maker development, and molecular breeding. Some successful cases have proved the usefulness and efficiency of this platform. The platform is helpful for enhancing utilization of soybean genetic resources in sustainable crop improvement for food security. The efficient utilization of this platform in the future is relying on accurate phenotyping methods, abundant functional markers, high-throughput genotyping platforms, and effective breeding programs.

Microbial diversity of ticks and a novel typhus group Rickettsia species (Rickettsiales bacterium Ac37b) in Inner Mongolia, China.

Ticks can carry multiple pathogens, and Inner Mongolia's animal husbandry provides excellent environmental conditions for ticks. This study characterized the microbiome of ticks from different geographical locations in Inner Mongolia; 905 Dermacentor nuttalli and 36 Ixodes persulcatus were collected from sheep in three main pasture areas and from bushes within the forested area. Mixed DNA samples were prepared from three specimens from each region and tick species. Microbial diversity was analyzed by 16S rRNA sequencing, and α and ß diversity were determined. The predominant bacterial genera were Rickettsia (54.60%), including Rickettsiales bacterium Ac37b (19.33%) and other Rickettsia (35.27%), Arsenophonus (11.21%), Candidatus Lariskella (10.84%), and Acinetobacter (7.17%). Rickettsia bellii was identified in I. persulcatus, while Rickettsiales bacterium Ac37b was found in D. nuttalli from Ordos and Chifeng. Potential Rickettsia and Anaplasma coinfections were observed in the Ordos region. Tick microbial diversity analysis in Inner Mongolia suggests that sheep at the sampling sites were exposed to multiple pathogens.

Title: Diversité microbienne des tiques et nouvelle espèce de Rickettsia du groupe du typhus (bactérie Rickettsiales Ac37b) en Mongolie intérieure, Chine. Abstract: Les tiques peuvent être porteuses de plusieurs agents pathogènes et l'élevage en Mongolie intérieure offre d'excellentes conditions environnementales pour les tiques. Cette étude a caractérisé le microbiome des tiques de différentes zones géographiques de Mongolie intérieure; 905 Dermacentor nuttalli et 36 Ixodes persulcatus ont été collectés sur des moutons dans trois principales zones de pâturage et dans des buissons de la zone forestière. Des échantillons d'ADN mixtes ont été préparés à partir de trois spécimens de chaque région et espèce de tique. La diversité microbienne a été analysée par séquençage de l'ARNr 16S et la diversité α et ß a été déterminée. Les genres bactériens prédominants étaient les Rickettsia (54,60 %), dont la bactérie Rickettsiales Ac37b (19,33 %) et d'autres Rickettsia (35,27 %), Arsenophonus (11,21 %), Candidatus Lariskella (10,84 %) et Acinetobacter (7,17 %). Rickettsia bellii a été identifiée chez I. persulcatus, tandis que la bactérie Rickettsiales Ac37b a été trouvée chez D. nuttalli d'Ordos et Chifeng. Des co-infections potentielles à Rickettsia et Anaplasma ont été observées dans la région d'Ordos. L'analyse de la diversité microbienne des tiques en Mongolie intérieure montre que les moutons présents sur les sites d'échantillonnage sont exposés à plusieurs agents pathogènes.

High gas sensing performance of one-step-synthesized Pd-ZnO nanoflowers due to surface reactions and modifications.

Pd-ZnO nanoflowers with high uniformity were prepared via a novel one-step hydrothermal route. High sensitivity, fast response, high selectivity and low work temperature are obtained from Pd-ZnO nanoflower sensors. The sensitivity upon exposure to 300 ppm ethanol is up to 168 at 300 °C and maintains 2.6 at 120 °C. Such behaviors can be attributed to Schottky contact at the Pd/ZnO interface and catalytic activity of Pd nanoparticles. The present results open a way for uniform surface modification of one-dimensional nanostructures with Pd nanoparticles and further enhancing their gas sensing performance.

Enhanced gas sensing performance of SnO2/α-MoO3 heterostructure nanobelts.

Extremely high sensitivity and low working temperature of gas sensors are realized from SnO(2)/α-MoO(3) heterostructure nanobelts. Their sensitivity against 500 ppm ethanol is up to 67.76 at the working temperature of 300 °C, which is higher than that of bare α-MoO(3) and SnO(2) nanostructures. Also the working temperature can be lowered down to 120 °C. Such behaviors are attributed to the variation of the junction barrier at the SnO(2)/α-MoO(3) interface. The present results imply that heterostructured 1D nanomaterials may yield gas sensors with improved characteristics, and can be applied to a wide range of gas sensors.

SnO2/WO3 core-shell nanorods and their high reversible capacity as lithium-ion battery anodes.

WO(3) nanorods are uniformly coated with SnO(2) nanoparticles via a facile wet-chemical route. The reversible capacity of SnO(2)/WO(3) core-shell nanorods is 845.9 mA h g(-1), higher than that of bare WO(3) nanorods, SnO(2) nanostructures, and traditional theoretical results. Such behavior can be attributed to a novel mechanism by which nanostructured metallic tungsten makes extra Li(2)O (from SnO(2)) reversibly convert to Li(+). This mechanism is confirmed by x-ray diffraction results. Our results open a way for enhancing the reversible capacity of alloy-type metal oxide anode materials.

Abnormal gas sensing characteristics arising from catalyzed morphological changes of ionsorbed oxygen.

Abnormal gas sensing characteristics are observed at low temperature in uniformly loaded Pt@SnO(2) nanorod gas sensors. The sensors operated at 200 degrees C exhibit opposite variations of resistances, and the change of resistance decreases with increasing ethanol concentration. In contrast, the sensors operated at 300 degrees C show regular behavior and the sensitivity is extremely high. Such behaviors are ascribed to Pt-catalyzed morphological changes of ionsorbed oxygen at low temperature. The present results are the bases for further investigating the effect of ionsorbed oxygen morphologies on gas sensing.

Cyclooxygenase 2 polymorphism and colorectal cancer: -765G>C variant modifies risk associated with smoking and body mass index.

AIM: To explore whether cyclooxygenase 2 (COX-2) -765G>C polymorphism is associated with susceptibility of colorectal cancer (CRC) and to evaluate the risk of colorectal cancer in relation to environmental exposures and polymorphism. METHODS: We conducted a case-control study of 137 patients with colorectal cancer and 199 cancer-free controls in northeast China. Multivariate logistic regression analysis was performed to calculate the adjusted odds ratio (OR) and 95% confidence interval (95% CI). RESULTS: The -765G>C polymorphism was not independently associated with CRC risk. However, risk associated with the polymorphism differed by smoking and body mass index (BMI). Smoking and BMI associated risks were stronger among those with -765GG genotype, showing that smokers had a 2.682-fold greater risk of CRC than nonsmokers (51/43 vs 68/126, P = 0.006). Compared to those with a normal body mass index (BMI 18.5-22.9), those with overweight (BMI 23-24.9) had a 3.909-fold higher risk of CRC (OR = 3.909, 95% CI = 2.081-7.344; P < 0.001), while those with obesity (BMI > 25) had a 2.031- fold higher risk of CRC (OR = 1.107, 95% CI = 1.107-3.726; P = 0.022). CONCLUSION: Although COX-2 -765G>C polymorphism is not associated with an increased risk of CRC, -765GG genotype appears to be related to an increased risk in the presence of smoking and higher BMI.

Penetration and saturation of lysozyme in phospholipid bilayers.

We show that the combination of X-ray reflectivity, tryptophan fluorescence spectrum, and fluorescence quenching by bromine provides a useful tool to probe the location of lysozyme in lipid bilayers. To this end, we prepare lamellar complexes composed of phospholipids and lysozyme on solid surfaces using a solution-casting method. The proteins lie spontaneously between adjacent bilayers in the complexes. The results indicate that lysozyme may penetrate into the lipid bilayers. But the penetration depth is very shallow, and the tryptophan residues do not penetrate beyond the interface between the hydrocardon core and the headgroup region of the lipid bilayer. The penetration becomes saturated when more proteins are incorporated into the lamellar complex. The excess proteins stay in the interlamellar aqueous layers.

Matrix metalloproteinase-9-1562C>T polymorphism may increase the risk of lymphatic metastasis of colorectal cancer.

AIM: To explore the role of the matrix metalloproteinase-9 (MMP-9) polymorphism in colorectal cancer (CRC) in a northeast Chinese population. METHODS: Genotyping of MMP-9-1562C>T and 279R>Q polymorphisms was carried out on blood samples from 137 colorectal cancer patients and 199 controls using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Multivariate logistic regression models were used to calculate adjusted odds ratios (OR) and 95% confidence intervals (95% CI). RESULTS: The distribution of MMP-9 -1562C>T and 279 R>Q genotype was not significantly associated with the risk of CRC. However, the risk of llymph node metastasis of CRC was increased in patients with the -1562T allele (OR = 2.601; 95% CI = 1.160-5.835; P = 0.022). The frequency of MMP-9 279RR + RQ genotype was higher than the QQ genotype among CRC patients younger than sixty years old (OR = 0.102; 95% CI = 0.013-0.812; P = 0.012). CONCLUSION: Our results indicated that the MMP-9-1562C>T polymorphism affects lymph node metastasis of CRC. In addition, the MMP-9 279R allele may lead to a younger age of onset of colorectal cancer.

[Inhibitory effect of siRNA on heparanase expression and invasion ability of gastric cancer cells: an in vitro experiment].

OBJECTIVE: To investigate the inhibitory effect of siRNA on heparanase expression and invasion ability gastric cancer cells. METHODS: A heparanase mRNA-targeting double-stranded siRNA was designed with the bioinformatics technology. Human gastric cancer cells of the line SGC7901 were cultured and transfected with the siRNA of the concentrations of 5, 10, 20, and 40 nmol/L respectively. Forty-eight hours later RT-PCR and Western blotting were applied to detect the mRNA and protein expression of heparanase. Millicell chamber assay was performed to detect the invasion ability of the SGC7901 cells. Blank control group and negative control group were set. RESULTS: The mRNA expression level of the cells transfected with the siRNA of the concentrations 20 nmol/L and 40 nmol/L were 0.207 +/- 0.095 and 0.200 +/- 0.085 respectively, both significantly lower than that of the control group (0.60 +/- 0.09, both P < 0.05). Western blotting showed that the protein expression of heparanase of the different siRNA subgroups were all decreased dose-dependently; and no heparanase band was seen in the 40 nmol/L subgroup. The invasion rate of the siRNA group was significantly lower than that of the control group with a mean inhibition rate of (61 +/- 36)%. CONCLUSION: RNAi inhibits the expression of heparanase and the invasion ability of human gastric cancer cells. Heparanase may be a new target in treatment of gastric cancer's metastasis.

Follicle-Stimulating Hormone Induces Postmenopausal Dyslipidemia Through Inhibiting Hepatic Cholesterol Metabolism.

CONTEXT: The elevated low-density-lipoprotein cholesterol (LDL-C) in menopausal women is associated with higher risks of cardiovascular diseases. OBJECTIVE: The aim of this study is to investigate the influence and mechanism by which high postmenopausal FSH levels affect lipid profiles. METHODS: The serum FSH and lipid levels were examined in 400 Chinese postmenopausal women. The FSH receptor (FSHR) expression was identified in liver and HepG2 cells by PCR and Western blotting. The effects of FSH on lipid metabolism were confirmed in an ovariectomized mouse model by using GnRH agonist with or without additional FSH to mimic different FSH status. LDL receptor (LDLR), a necessary factor for clearance of LDL-C through endocytosis, was examined by PCR and Western blotting. RESULTS: The postmenopausal women with higher serum FSH (≥78.3 IU/L at baseline) had higher serum total cholesterol and LDL-C levels than those women with FSH levels of 40-78.3 IU/L (P < .01). The improvements of total cholesterol and LDL-C levels were more significant in higher FSH women group after treatment with hormone replacement therapy. It was only in the women whose FSH levels were reduced more than 30% after hormone replacement therapy who showed significant improvement of lipid levels. Ovariectomized mice had high serum FSH and lipids levels and reduced hepatic LDLR expression. In HepG2 cells, FSH inhibited the LDLR in a dose- and time-dependent manner, and the FSHR knockdown with specific siRNA reversed the lower LDLR induced by FSH. CONCLUSIONS: FSH may interact with its receptors in hepatocytes and reduce LDLR levels, which subsequently attenuates the endocytosis of LDL-C, resulting in an elevated circulating LDL-C level.

Cystatin C Shifts APP Processing from Amyloid-ß Production towards Non-Amyloidgenic Pathway in Brain Endothelial Cells.

Amyloid-ß (Aß), the major component of neuritic plaques in Alzheimer's disease (AD), is derived from sequential proteolytic cleavage of amyloid protein precursor (APP) by secretases. In this study, we found that cystatin C (CysC), a natural cysteine protease inhibitor, is able to reduce Aß40 secretion in human brain microvascular endothelial cells (HBMEC). The CysC-induced Aß40 reduction was caused by degradation of ß-secretase BACE1 through the ubiquitin/proteasome pathway. In contrast, we found that CysC promoted secretion of soluble APPα indicating the activated non-amyloidogenic processing of APP in HBMEC. Further results revealed that α-secretase ADAM10, which was transcriptionally upregulated in response to CysC, was required for the CysC-induced sAPPα secretion. Knockdown of SIRT1 abolished CysC-triggered ADAM10 upregulation and sAPPα production. Taken together, our results demonstrated that exogenously applied CysC can direct amyloidogenic APP processing to non-amyloidgenic pathway in brain endothelial cells, mediated by proteasomal degradation of BACE1 and SIRT1-mediated ADAM10 upregulation. Our study unveils previously unrecognized protective role of CysC in APP processing.

Preliminary analysis of stem cell-like cells in human neuroblastoma.

BACKGROUND: Neuroblastoma is an embryonic neoplasm originating from the neural crest with cellular heterogeneity as one of its oncobiological characteristics. This study was undertaken to determine whether human neuroblastoma contains stem cell-like cells. METHODS: Twenty patients with neuroblastoma who have been treated in our hospital since January 2005 were divided into pre-operative chemotherapy (10 patients) and non-chemotherapy (10) groups. Tumor specimens of the patients were taken and paraffin sections were made. The expressions of stem cell markers CD133, ABCG2, CD117 and nestin were immunohistochemically detected in the specimens. Neuroblastoma cells were stained with Hoechst 33342 and PI. The side population (SP) cells were analyzed by the fluorescence-activated cell sorter. The disparity drug resistance to cisplatin (DDP) of SP and non-SP cells was measured with MTT colorimetric assay. The oncogenicity of SP and non-SP cells was identified in nude mice. RESULTS: There was no significant difference in the expression intensity of CD117 and nestin between the two groups of specimens (P>0.05). There was a significant difference between the two groups in terms of the expression intensity of CD133 and ABCG2 (P<0.05). The SP cells accounted for 0.2%-1.3% of the total human neuroblastoma cells and were decreased to 0.1%-0.5% after verapamil treatment. The SP and non-SP cells showed disparity in cell growth experiment and drug resistance to DDP. Oncogenicity experiment revealed that nude mice could erupt tumor by an injection of l×10(6) SHSY5Y and WIV SP cells. However, the nude mice could not form tumor by an injection of l×10(6) non-SP cells. CONCLUSION: Neuroblastoma might contain cancer stem cell-like cells.

Core-shell α-Fe2O3@α-MoO3 nanorods as lithium-ion battery anodes with extremely high capacity and cyclability.

α-Fe2O3 nanoparticles are uniformly coated on the surface of α-MoO3 nanorods through a two-step hydrothermal synthesis method. As the anode of a lithium-ion battery, α-Fe2O3@α-MoO3 core-shell nanorods exhibit extremely high lithium-storage performance. At a rate of 0.1 C (10 h per half cycle), the reversible capacity of α-Fe2O3@α-MoO3 core-shell nanorods is 1481 mA h g(-1) and a value of 1281 mA h g(-1) is retained after 50 cycles, which is much higher than that retained by bare α-MoO3 and α-Fe2O3 and higher than traditional theoretical results. Such a good performance can be attributed to the synergistic effect between α-Fe2O3 and α-MoO3 , the small size effect, one-dimensional nanostructures, short paths for lithium diffusion, and interface spaces. Our results reveal that core-shell nanocomposites have potential applications as high-performance lithium-ion batteries.

Luminol-K3Fe(CN)6 chemiluminescence system for the determination of glipizide.

A rapid and sensitive flow-injection chemiluminescence (CL) method for the determination of glipizide was developed on the basis of finding that glipizide can enhance the CL intensity of the luminol-K3Fe(CN)6 system. In optimum condition, the increased CL intensity was directly proportional to the concentration of glipizide in the range from 4.0×10-8 g/mL to 1.0×10-6 g/mL and the detection limit was 1.0×10-8 g/mL glipizide. The relative standard deviation (RSD) of the developed method was 2.1% with 11 repeated measurements of 1.0×10-7 g/mL glipizide. The developed method has been successfully applied to the analysis of glipizide in its pharmaceutical preparations.

Synergistic effect of SnO2/ZnWO4 core-shell nanorods with high reversible lithium storage capacity.

High reversible lithium storage capacity is obtained from novel SnO2/ZnWO4 core-shell nanorods. At C/20 (20 h per half cycle) rate, the reversible capacity of SnO2/ZnWO4 core-shell nanorods is as high as 1000 mA h g(-1), much higher than that of pure ZnWO4, SnO2, or the traditional theoretical result of the simple mixture. Such performance can be attributed to the synergistic effect between the nanostructured SnO2 and ZnWO4. The distinct electrochemical activity of ZnWO4 nanorods probably activates the irreversible capacity of the SnO2 nanoparticles. These results indicate that high-performance lithium ion batteries can be realized by introducing the synergistic effect of one-dimensional core-shell nanocomposites.

SnO2/α-MoO3 core-shell nanobelts and their extraordinarily high reversible capacity as lithium-ion battery anodes.

Extraordinarily high reversible capacity of lithium-ion battery anodes is realized from SnO(2)/α-MoO(3) core-shell nanobelts. The reversible capacity is much higher than traditional theoretical results. Such behavior is attributed to α-MoO(3) that makes extra Li(2)O reversibly convert to Li(+).

Porous Co3O4 nanoneedle arrays growing directly on copper foils and their ultrafast charging/discharging as lithium-ion battery anodes.

Ultrafast charging/discharging of lithium-ion battery anodes is realized from porous Co(3)O(4) nanoneedle arrays growing on copper foils. Their charge time can be shortened to ∼6 s, their reversible capacity at 0.5C rate is 1167 mAh/g. This implies that nano-arrays growing directly on copper foils are good candidates for anodes.

Cyclooxygenase-2 polymorphisms and susceptibility to gastric carcinoma: a meta-analysis.

AIM: To investigate the association of the cyclooxygenases-2 (COX-2) polymorphisms and susceptibility to gastric cancer (GC) by means of meta-analysis. METHODS: Publications addressing the association between polymorphisms of COX-2 and susceptibility to GC were selected from the MEDLINE, EMBASE and CBMdisc databases. Data was extracted from the studies by 2 independent reviewers. The meta-analyses were performed by RevMan 5.0.23. From these data, odds ratio (OR) with 95% confidence interval (CI) was calculated. RESULTS: Ten studies were retrieved reporting a total of 11 COX-2 polymorphisms. Carriers of -765C, -1195A, -1290G, *2430T alleles and *429TT genotype revealed increased risk for GC (OR = 1.71, 95% CI: 1.01-2.90, P = 0.05; OR = 1.58, 95% CI: 1.05-2.38, P = 0.03; OR = 1.55, 95% CI: 1.01-2.39, P = 0.05; OR = 2.62, 95% CI: 1.20-5.73, P = 0.02 and OR = 0.74, 95% CI: 0.59-0.95, P = 0.02, respectively). CONCLUSION: The -765C, -1195A, -1290G, *2430T alleles and *429TT genotype of COX-2 polymorphisms were determined a significant association with susceptibility to GC.