Spinel Nanostructures for the Hydrogenation of CO2 to Methanol and Hydrocarbon Chemicals.

Composite oxides have been widely applied in the hydrogenation of CO/CO2 to methanol or as the component of bifunctional oxide-zeolite for the synthesis of hydrocarbon chemicals. However, it is still challenging to disentangle the stepwise formation mechanism of CH3OH at working conditions and selectively convert CO2 to hydrocarbon chemicals with narrow distribution. Here, we investigate the reaction network of the hydrogenation of CO2 to methanol over a series of spinel oxides (AB2O4), among which the Zn-based nanostructures offer superior performance in methanol synthesis. Through a series of (quasi) in situ spectroscopic characterizations, we evidence that the dissociation of H2 tends to follow a heterolytic pathway and that hydrogenation ability can be regulated by the combination of Zn with Ga or Al. The coordinatively unsaturated metal sites over ZnAl2Ox and ZnGa2Ox originating from oxygen vacancies (OVs) are evidenced to be responsible for the dissociative adsorption and activation of CO2. The evolution of the reaction intermediates, including both carbonaceous and hydrogen species at high temperatures and pressures over the spinel oxides, has been experimentally elaborated at the atomic level. With the integration of a series of zeolites or zeotypes, high selectivities of hydrocarbon chemicals with narrow distributions can be directly produced from CO2 and H2, offering a promising route for CO2 utilization.

Dynamical behaviors of a delayed SIR information propagation model with forced silence function and control measures in complex networks.

Due to the advanced network technology, there is almost no barrier to information dissemination, which has led to the breeding of rumors. Intended to clarify the dynamic mechanism of rumor propagation, we formulate a SIR model with time delay, forced silence function and forgetting mechanism in both homogeneous and heterogeneous networks. In the homogeneous network model, we first prove the nonnegativity of the solutions. Based on the next-generation matrix, we calculate the basic reproduction number R0. Besides, we discuss the existence of equilibrium points. Next, by linearizing the system and constructing a Lyapunov function, the local and global asymptotically stability of the equilibrium points are found. In the heterogeneous network model, we derive the basic reproduction number R00 through the analysis of a rumor-prevailing equilibrium point E∗. Moreover, we conduct the local and global asymptotic stability analysis for the equilibrium points according to the LaSalle's Invariance Principle and stability theorem. As long as the maximum spread rate ß is large enough, the rumor-prevailing point E∗ is locally asymptotically stable when R00>1. Additionally, it hits that the system exists bifurcation behavior at R00=1 due to the newly added forced silence function. Later, after adding two controllers to the system, we research the problem of optimal control. Finally, aimed at authenticating the above theoretical results, a serious of numerical simulation experiments are carried out.

Changes in TFG gene expression in bovine leucocytes transformed by Theileria annulata.

Theileria annulata schizont-infected host cells in culture in vitro show unlimited proliferation similar to tumor cells; thus far, T. annulata and T. parva are the only eukaryotes that have been found to transform mammalian cells (immortalized). The transformation of these cells is reversible; when the parasite is eliminated in transformed cells by buparvaquone (BW720c), the host cells show normal growth and apoptosis. TFG is a tropomyosin-receptor kinase fused gene that is conserved among many species and is an important proto-oncogene. In this study, the bovine TFG gene was amplified by PCR from the cDNA of T. annulata schizont-transformed cells, cloned into the pGEX-4T-1 vector and expressed in Escherichia coli BL21 (DE3). After purification, the fusion protein was injected into rabbits to produce polyclonal antibodies. Using T. annulata-transformed cells together with BW720c treatment to kill the parasite, we aimed to identify changes in TFG gene expression by real-time PCR and Western blotting. The results showed that the bovine TFG gene was ~582 bp in size; SDS-PAGE analysis showed that the fusion protein was expressed in BL21 (DE3) cells with a molecular mass of 48 kD, and Western blotting indicated that the polyclonal antibodies could react with bovine TFG proteins from T. annulata-transformed cells and showed high specificity. Compared with that in the control group, the transcription level of the host TFG gene decreased significantly in the BW720c test group, and the expression of host tumor-related TFG protein decreased sharply after 72 h of drug treatment, suggesting that the TFG protein expression in transformed cells was directly related to T. annulata. This finding laid a foundation for further study on the interaction between T. annulata and host cells.

Metabolomic profiling of bovine leucocytes transformed by Theileria annulata under BW720c treatment.

BACKGROUND: When Theileria annulata infects host cells, it undertakes unlimited proliferation as tumor cells. Although the transformed cells will recover their limited reproductive characteristics and enter the apoptosis process after treatment with buparvaquone (BW720c), the metabolites and metabolic pathways involved are not clear. METHODS: The transformed cells of T. annulata were used as experimental materials, and the buparvaquone treatment group and DMSO control group were used. Qualitative and quantitative analysis was undertaken of 36 cell samples based on the LC-QTOF platform in positive and negative ion modes. The metabolites of the cell samples after 72 h of drug treatment were analyzed, as were the different metabolites and metabolic pathways involved in the BW720c treatment. Finally, the differential metabolites and metabolic pathways in the transformed cells were found. RESULTS: A total of 1425 metabolites were detected in the negative ion mode and 1298 metabolites were detected in the positive ion mode. After drug treatment for 24 h, 48 h, and 72 h, there were 56, 162, and 243 differential metabolites in negative ion mode, and 35, 121, and 177 differential metabolites in positive ion mode, respectively. These differential metabolites are mainly concentrated on various essential amino acids. CONCLUSION: BW720c treatment induces metabolic disturbances in T. annulata-infected cells by regulating the metabolism of leucine, arginine, and L-carnitine, and induces host cell apoptosis.

Stability behavior of a two-susceptibility SHIR epidemic model with time delay in complex networks.

Taking two susceptible groups into account, we formulate a modified subhealthy-healthy-infected-recovered (SHIR) model with time delay and nonlinear incidence rate in networks with different topologies. Concretely, two dynamical systems are designed in homogeneous and heterogeneous networks by utilizing mean field equations. Based on the next-generation matrix and the existence of a positive equilibrium point, we derive the basic reproduction numbers R 0 1 and R 0 2 which depend on the model parameters and network structure. In virtue of linearized systems and Lyapunov functions, the local and global stabilities of the disease-free equilibrium points are, respectively, analyzed when R 0 1 < 1 in homogeneous networks and R 0 2 < 1 in heterogeneous networks. Besides, we demonstrate that the endemic equilibrium point is locally asymptotically stable in homogeneous networks in the condition of R 0 1 > 1 . Finally, numerical simulations are performed to conduct sensitivity analysis and confirm theoretical results. Moreover, some conjectures are proposed to complement dynamical behavior of two systems.

Assessment of probiotic adhesion and inhibitory effect on Escherichia coli and Salmonella adhesion.

In this study, we screened bacterial strains to identify specific probiotics to treat pig diarrhea caused by Escherichia coli or Salmonella. The potential probiotics were assayed for their survival in gastrointestinal solution, their antimicrobial activity, cell-surface properties, adhesion to Caco-2 cells, and inhibition of pathogen adhesion. Nine out of the 20 strains tested showed high tolerance of a simulated gastrointestinal environment and six strains exerted antagonistic effects against enterohemorrhagic E. coli (EHEC) O157:H7 and Salmonella Typhimurium MQ. Lactobacillus johnsonii pDX1e exhibited a higher potent antibacterial activity. Four strains (pDX1a, pDX1e, pDX3a, and pDX5a) displayed auto-aggregation, hydrophobicity, and adhesion to Caco-2 cells similar to those of the reference strain Lacticaseibacillus rhamnosus GG (LGG). Enterococcus durans pDX5a showed the highest adhesion capacity (13.86%), followed by the reference strain LGG (11.20%). All the tested strains competitively suppressed the attachment of pathogens to Caco-2 cells (by 30.73-55.18%); L. johnsonii pDX1e and Ent. durans pDX5a significantly inhibited the adhesion of pathogens by substitution and exclusion, respectively. Therefore, pDX1e and pDX5a were selected as probiotic strains for further investigation and application.

Screen of anti-migraine active compounds from Duijinsan by spectrum-effect relationship analysis and molecular docking.

ETHNOPHARMACOLOGICAL RELEVANCE: Duijinsan (DJS) is a famous Chinese medicine prescription composed of Radix scutellariae (RS) and Rhei Radix (RRR), which has been mainly used for treating migraine. AIM OF THE STUDY: This study aimed to uncover the anti-migraine active compounds from DJS and preliminary predicted the pharmacological mechanism by evaluating the spectrum-effect relationship between high-performance liquid chromatography (HPLC) fingerprints and anti-migraine effects of Duijinsan (DJS) extract combined with molecular docking. MATERIALS AND METHODS: HPLC and LC-MS were applied for chemical analyses of DJS extracts in different proportions. Inhibition of DJS extracts on trigeminal nerve cell releasing calcitonin gene related peptide (CGRP) experiment was performed. The active compounds were screened by spectrum-effect relationship analysis and confirmed by molecular docking and the activities of major predicted compounds were validated in vitro. RESULTS: Twenty-six common peaks were assigned and identified from the fingerprints of different proportions DJS extracts. In vitro experimental results showed that DJS extracts inhibited inflammation and release of CGRP from trigeminal nerve cells. Five predicted active compounds, Chrysin 6-C-arabinoside 8-C-glucoside, Chrysin 6-C-glucoside 8-C-arabinoside, baicalin, Chrysin-7-O-Beta-D-glucoronide and Oroxylin A 7-O-glucuronide were sorted out according to spectrum-effect relationship analysis and molecular docking comprehensively. In vitro validation experiments showed that all the predicted compounds inhibited the CGRP releasing and the activation of TRPV1 channel. Baicalin, chrysin-7-O-ß-D-glucuronide and Oroxylin A-7-glucoronide significantly inhibited the activation of TRPV1 channel. CONCLUSION: Chrysin 6-C-arabinoside 8-C-glucoside, Chrysin 6-C-glucoside 8-C-arabinoside, baicalin, Chrysin-7-O-Beta-D-glucoronide and Oroxylin A 7-O-glucuronide which can inhibit the CGRP releasing and the activation of TRPV1 channel were screened as the anti-migraine active compounds by spectrum-effect relationship analysis and molecular docking.

Initial serum HCG levels are higher in pregnant women with a male fetus after fresh or frozen single blastocyst transfer: A retrospective cohort study.

OBJECTIVE: Substantial previous studies have almost reached an agreement on the gender effect on maternal serum human chorionic gonadotropin (MsHCG) in and after the late first trimester of pregnancy. However, there is little knowledge of the sex-related difference in MsHCG level at the preliminary stage of pregnancy. The purpose of this study is to reveal this difference in women after fresh or frozen single blastocyst transfer (SBT). MATERIALS AND METHODS: A total of 252 fresh SBT cycles and 1486 frozen-thawed SBT cycles collected between June 1, 2014 and May 30, 2017 were retrospectively analyzed in our center. Patients with MsHCG level ≥5 IU/L on day 11 after transfer, achieving a singleton intrauterine pregnancy and subsequent live birth were included. We compared MsHCG levels between women gave birth to a male neonate and those gave birth to a female one in fresh or frozen SBT cycles, respectively. RESULTS: A total of 136 neonates including 57 females and 79 males were born following fresh SBT. The male-female ratio was 1.39:1. The average MsHCG level of male fetuses was higher than that of female fetuses on day 11 after transfer (549.82 ± 253.24 IU/L versus 439.03 ± 198.41 IU/L, P < 0.05). Correspondingly, a total of 431 infants was born after frozen SBT, containing 188 females and 243 males. The male-female ratio was 1.29:1. Initial MsHCG level remained higher in women with a male neonate than the counterparts with a female neonate (894.43 ± 622.17 IU/L versus 758.05 ± 624.33 IU/L, P < 0.05). It was also found the pregnant women following frozen-thawed SBT exhibited higher initial MsHCG level than those following fresh SBT in whether male-bearing or female-bearing gestations. CONCLUSIONS: MsHCG levels are higher in pregnant women with a male fetus than those with a female one on day 11 after fresh or frozen SBT. A sex-specific response to the stress in the process of in vitro embryo culture was suggested.

[IVOS â ¡ versus Sperm Class Analyzer in the results of semen analysis].

OBJECTIVE: To compare the results obtained from the computer-aided sperm analysis (CASA) systems of the two fully-automated commercial sperm quality analyzers, Hamilton-Thorn IVOS Ⅱ (IVOS Ⅱ) and Spanish Sperm Class Analyzer (SCA). METHODS: A total of 99 semen samples were collected in the Center of Reproduction of Shenzhen Zhongshan Urology Hospital from September 2018 to October 2018 and, according to the sperm concentration, divided into groups A (<15 ×106/ml), B (15－50 ×106/ml) and C (>50 ×106/ml). IVOS Ⅱ, SCA and manual microscopy were used for the examination of each sample, followed by comparison of the sperm concentration, sperm motility and percentage of progressively motile sperm (PMS) obtained from IVOS Ⅱ and SCA. RESULTS: The sperm concentrations derived from IVOS Ⅱ and SCA were significantly higher than that from manual microscopy in group A (ï¼»10.24 ± 4.60ï¼½ and ï¼»10.20 ± 5.11ï¼½ vs ï¼»8.45 ± 4.15ï¼½ ×106/ml, P < 0.05), but showed no statistically significant difference in group B (ï¼»30.95 ± 11.84ï¼½ and ï¼»31.81 ± 12.90ï¼½ vs ï¼»29.14 ± 10.65ï¼½ ×106/ml, P > 0.05) or C (ï¼»102.14 ± 45.97ï¼½ and ï¼»109.48 ± 46.32ï¼½ vs ï¼»104.74 ± 41.87ï¼½ ×106/ml, P > 0.05). Significant differences were not observed between IVOS Ⅱ and SCA in the percentage of PMS (ï¼»24.21 ± 14.62ï¼½% vs ï¼»23.92 ± 15.42ï¼½%, P > 0.05) or sperm motility (ï¼»37.48 ± 19.34ï¼½% vs ï¼»37.69 ± 16.61ï¼½%, P > 0.05) in group B, nor in group C (PMS: ï¼»30.80 ± 12.06ï¼½% vs ï¼»32.98 ± 16.10ï¼½%, P > 0.05; sperm motility: ï¼»44.50 ± 15.62ï¼½% vs ï¼»47.26 ± 17.46ï¼½%, P > 0.05). Both the percentage of PMS and sperm motility obtained from IVOS Ⅱ were remarkably lower than those derived from SCA in group A (PMS: ï¼»18.54 ± 12.96ï¼½% vs ï¼»22.90 ± 12.88ï¼½%, P < 0.05; sperm motility: ï¼»26.97 ± 14.05ï¼½% vs ï¼»34.90 ± 15.18ï¼½%, P < 0.05). IVOS Ⅱ and SCA both showed a high repeatability (CV <15%), and the former exhibited an even higher one than the latter, in detection of sperm concentration, sperm motility and the percentage of PMS. CONCLUSIONS: IVOS Ⅱ and SCA both had a good consistency in the results of sperm concentration, motility and progressive motility, but showed a poor comparability with low-concentration semen samples.

IVOS Ⅱ versus Sperm Class Analyzer in the results of semen analysis / 中华男科学杂志

Objective@#To compare the results obtained from the computer-aided sperm analysis (CASA) systems of the two fully-automated commercial sperm quality analyzers, Hamilton-Thorn IVOS Ⅱ (IVOS Ⅱ) and Spanish Sperm Class Analyzer (SCA).@*METHODS@#A total of 99 semen samples were collected in the Center of Reproduction of Shenzhen Zhongshan Urology Hospital from September 2018 to October 2018 and, according to the sperm concentration, divided into groups A (50 ×10⁶/ml). IVOS Ⅱ, SCA and manual microscopy were used for the examination of each sample, followed by comparison of the sperm concentration, sperm motility and percentage of progressively motile sperm (PMS) obtained from IVOS Ⅱ and SCA.@*RESULTS@#The sperm concentrations derived from IVOS Ⅱ and SCA were significantly higher than that from manual microscopy in group A (［10.24 ± 4.60］ and ［10.20 ± 5.11］ vs ［8.45 ± 4.15］ ×10⁶/ml, P 0.05) or C (［102.14 ± 45.97］ and ［109.48 ± 46.32］ vs ［104.74 ± 41.87］ ×10⁶/ml, P > 0.05). Significant differences were not observed between IVOS Ⅱ and SCA in the percentage of PMS (［24.21 ± 14.62］% vs ［23.92 ± 15.42］%, P > 0.05) or sperm motility (［37.48 ± 19.34］% vs ［37.69 ± 16.61］%, P > 0.05) in group B, nor in group C (PMS: ［30.80 ± 12.06］% vs ［32.98 ± 16.10］%, P > 0.05; sperm motility: ［44.50 ± 15.62］% vs ［47.26 ± 17.46］%, P > 0.05). Both the percentage of PMS and sperm motility obtained from IVOS Ⅱ were remarkably lower than those derived from SCA in group A (PMS: ［18.54 ± 12.96］% vs ［22.90 ± 12.88］%, P < 0.05; sperm motility: ［26.97 ± 14.05］% vs ［34.90 ± 15.18］%, P < 0.05). IVOS Ⅱ and SCA both showed a high repeatability (CV <15%), and the former exhibited an even higher one than the latter, in detection of sperm concentration, sperm motility and the percentage of PMS.@*CONCLUSIONS@#IVOS Ⅱ and SCA both had a good consistency in the results of sperm concentration, motility and progressive motility, but showed a poor comparability with low-concentration semen samples.

Insights of sex determination and differentiation from medaka as a teleost model.

The mechanisms of sex determination and differentiation in fish are highly divergent with a broad range of gonadal differentiation types from hermaphroditism to gonochorism. Multiple triggers regulate the process of sexual differentiation including genetic or environmental factors (temperature, light, hormones and/or pH value, etc.). In recent years, with the advances of molecular technologies and genetic engineering approaches, there are significant breakthroughs in identifying the master genes of vertebrate sex determination and differentiation. In this review, we explore the fundamental and molecular mechanisms underlying the sexual differentiation in teleost fish, using medaka (Oryzias latipes) as a model. We focus on the male pathways and factors, particularly on dmrt1, gsdf and amh genes involved in testicular differentiation, sexual reversal and plasticity. It is anticipated that new techniques will likely be developed in the field of sex manipulations and monosex breeding for fish aquaculture in the future.

Association of serum autoantibodies with pregnancy outcome of patients undergoing first IVF/ICSI treatment: A prospective cohort study.

The relevance of antiphospholipid (aPL), antinuclear (ANA) or antithyroid (ATA) antibodies in women undergoing in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) are controversial. The present study aims to investigate which autoantibodies are associated with the pregnancy outcome of patients undergoing first IVF/ICSI treatment. A total of 3763 IVF/ICSI patients were recruited from January to December 2015. Forty-five patients positive for aPL presenting adverse outcomes in their first cycle received low-dose aspirin treatment before the second transfer. Logistic regression analyses were performed to assess any association between autoantibodies and IVF/ICSI outcomes. The aCL-IgG was significantly associated with live birth rate (OR 0.58, 95% CI 0.36-0.96, p<0.05) and miscarriage rate (OR 2.04, 95% CI 1.23-3.40, p<0.01). The aCL-IgM was associated with miscarriage rate (OR 2.14, 95% CI 1.29-3.54, p<0.01). The aß2GPI-IgG was associated with implantation rate and clinical pregnancy rate (OR 0.61, 95% CI 0.24-0.96, p<0.05; OR 0.40, 95% CI 0.13-0.87, p<0.05, respectively). After the low-dose aspirin treatment, the live birth rate (37.0% vs. 19.1%, p<0.05) increased significantly in patients with positive for aPL. In contrary, the aß2GPI-IgM, ANA, anti-thyroglobulin (aTG) and anti-thyroperoxidase (aTPO) antibodies had no association with IVF/ICSI outcome. It is suggested that the presence of aCL-IgG, aCL-IgM and aß2GPI-IgG might exert a detrimental effect on IVF/ICSI outcomes. Low-dose aspirin treatment could be useful for patients positive for these antibodies. Therefore, it is suggested that these antibodies should be assessed prior to IVF/ICSI treatment.

Human chorionic gonadotropin potentially affects pregnancy outcome in women with recurrent implantation failure by regulating the homing preference of regulatory T cells.

PROBLEM: Human chorionic gonadotropin (hCG) and regulatory T cells (Tregs) have been suggested to play important roles during the initial stage of pregnancy. However, the clinical relevance and mechanism of the effects of hCG on Treg functions in women with recurrent implantation failure (RIF) remain to be elucidated. METHOD OF STUDY: Thirty-four RIF and twenty-three control women were included in the study. Endometrial and peripheral Tregs were analyzed by immunohistochemistry and flow cytometry, respectively. Tregs were generated from naïve CD4+ T cells by stimulation with anti-CD3/CD28 in the presence or absence of hCG, and the subsets were analyzed by flow cytometry, Western blotting, and qPCR. RESULTS: The percentages of endometrial FOXP3+ Tregs and peripheral CCR4+ FOXP3+ Tregs were significantly lower in the women with RIF than in the healthy controls. In addition, the percentages of CCR4+ FOXP3+ Tregs and TGF-ß-expressing FOXP3+ Tregs were increased following the stimulation of naïve CD4+ T cells with anti-CD3/CD28, and these increases were concomitant with AKT and ERK dephosphorylation. CONCLUSIONS: The results of this study provide novel evidence supporting a role of hCG in regulating the differentiation of peripheral FOXP3+ Tregs. The alterations of circulating Tregs may positively affect the pregnancy outcomes of patients with a history of RIF.

Involvement of sodium nitrite in the regulation of cancer stem cell properties in human hepatoma cells / 药学学报

Increasing evidence suggests that hepatocellular carcinomas (HCCs) are sustained by a distinct subpopulation of self-renewing cells known as cancer stem cells (CSC). However, our understanding of their regulation is limited. Rapid reversible changes of CSC-like cells within tumors may result from the effect of biological mediators found in the tumor microenvironment. This paper aims to explore how nitrite, a key cellular modulator whose level is elevated in many tumors, affects CSC-like phenotypes of human hepatoma cells SMMC-7721 cells. The SMMC-7721 cell line was cultured under serum-free conditions to produce floating spheres. The distribution of cell cycle was analyzed by flow cytometry, the capability of cells self-renew was detected by colony-forming capabilities and spheroid-formation assay, the expression of stemness protein such as CD133, CD90 and EpCAM were determined by flow cytometry and Western blot, cell invasion was analyzed by transwell assay, and viability of SMMC-7721 parental cells and spheroids cancer cells was determined by the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay. Xenograft tumor models were established by subcutaneously injecting SMMC-7721 spheroids cancer cells, the transplanted tumor tissue ROS levels was detected by reactive oxygen species (ROS) test kits, the expression of HIF-1α was observed by immunofluorescence. Our results showed that the SMMC-7721 spheroid cells were enriched with CSCs properties, indicated by the ability to self-renew, increased expression of CSCs markers, and increased resistance to chemotherapeutic drugs. Additionally, SMMC-7721 parental cells and spheroids cancer cells were treated with 150 μmol·L-1 sodium nitrite for 6 days, compared with control cells, an increased accumulation of G0/G1 phase cells was observable in treatment cells. Indeed, our data demonstrated that in parent cells and spheres cells that were treated with sodium nitrite for different time, the cells' ability to chemoresistance and invasion, clone-forming efficiencies and the spheres forming ability were significantly higher than that of control cells. Exposure of sodium nitrite regulated CSC-like phenotype, indicated by increased expression of known CSC markers, CD133, CD90 and EpCAM in the exposed parental cells, as well as in dormant spheroids cancer cells. Compared with the parent cells, the above effects of nitrite on the spheres cells were significantly enhanced. In vivo data also presented a more significant promotion of tumor xenograft growth from the nitrite treatment than from either of the control. Mechanistic analysis indicated that nitrite induced the upregulation of HIF-1α as well as the downregulation of ROS in the tumor microenvironment. These results suggest that nitrite increases the invasiveness of SMMC-7721 cells through up-regulation of tumor stemness.

Molecular epidemiological surveillance to assess emergence and re-emergence of tick-borne infections in tick samples from China evaluated by nested PCRs.

An investigation was performed to detect eight pathogens in ticks collected from grass tips or animals in the southern, central and northeast regions of China. DNA samples extracted from ticks were collected from ten different locations in eight provinces of China and subjected to screening for tick-borne pathogens, including Borrelia burgdorferi sensu lato, Ehrlichia spp., Rickettsia spp., Babesia/Theileria spp., Ehrlichia ruminantium, Coxiella burnetii, and Francisella tularensis, using nested PCR assays and sequencing analysis. The results indicated that Borrelia spp., Rickettsia spp., and Babesia/Theileria spp. were detected in all of the investigated provinces. Ehrlichia spp. was also found in all of the surveyed areas, except Guangxi, Luobei and Tonghe counties in Heilongjiang province. The average prevalence of these pathogens was 18.4% (95% CI=12.8-42.5), 60.3% (95% CI=18.2-65.3), 26.0% (95% CI=25.8-65.1), and 28.7% (95% CI=5.6-35.2), respectively. A sequencing analysis of the pCS20 gene of E. ruminantium revealed an E. ruminantium-like organism (1/849, 0.1%, 95% CI=0-0.3) in one tick DNA sample extracted from Rhipicephalus (Boophilus) microplus in Hunan. In addition, Borrelia americana in Ixodes persulcatus, Babesia occultans in Haemaphysalis qinghaiensis and both Rhipicephalus sanguineus and an Ehrlichia muris-like organism in R. (B.) microplus was detected, possibly for the first time in China. Four DNA sequences closely related to Borrelia carolinensis and/or Borrelia bissettii from Haemaphysalis longicornis, Candidatus Rickettsia principis from H. qinghaiensis, and I. persulcatus and Ehrlichia canis (named E. canis-like) from Haemaphysalis bispinosa were also detected in this work.

Effects of T-2 toxin on the regulation of steroidogenesis in mouse Leydig cells.

T-2 toxin is one of the mycotoxins, a group of type A trichothecenes produced by several fungal genera including Fusarium species, which may lead to the decrease of testosterone secretion in primary Leydig cells derived from mouse testis. The previous study demonstrated T-2 toxin decrease the testosterone biosynthesis in the primary Leydig cells derived from the mouse testis directly. In this study, we further examined the direct biological effects of T-2 toxin on the process of steroidogenesis, primarily in Leydig cells of mice. Leydig cells of mature mouse were purified by Percoll gradient centrifugation and the cell purity was determined by 3ß-hydroxysteroid dehydrogenase (3ß-HSD) staining. To examine the decrease in T-2 toxin-induced testosterone secretion, we measured the transcription level of three key steroidogenic enzymes including 3ß-HSD-1, cytochrome P450 side-chain cleavage (P450scc) enzyme, and steroidogenic acute regulatory (StAR) protein in T-2 toxin/human chorionic gonadotropin (hCG) co-treated cells. Our previous study showed that T-2 toxin (10(-7), 10(-8), and 10(-9) M) significantly suppressed hCG (10 ng/ml)-induced testosterone secretion. The studies demonstrated that the suppressive effect is correlated with a decrease in the level of transcription of 3ß-HSD-1, P450scc, and StAR (p < 0.05).

Exposure of human hepatoma cells to nitrite and ammonia promotes invasive activity through activation of ROS/ODC pathway / 药学学报

Recent studies have demonstrated that nitrite and ammonia levels are higher in the tumor environment, but their effects on cancer cells remains unclear. The present study was designed to determine the effects of nitrite and ammonia on tumor invasion and the role of reactive oxygen (ROS)/ornithine decarboxylase (ODC) pathway. SMMC-7721 cells were treated with sodium nitrite, ammonium chloride, sodium nitrite and ammonium chloride mixture for 24 h, the cell viability was analyzed using the MTT assay, cell invasion was analyzed with the transwell assay, the intracellular ROS levels were detected with a reactive oxygen species (ROS) test kits, the expression of intracellular ODC was examined with immunofluorescence and Western blot, the expression of matrix metallopeptidase-2(MMP-2) and MMP-9 were analyzed by Western blot. Compared with the control group, SMMC-7721 cells exhibited an increase in cell viability, invasion ability, ROS levels and ODC protein after exposure to 150 μmol·L-1 sodium nitrite and ammonium chloride mixture for 24 h. The invasive activity was reduced by ROS scavenger N-acetycysteine (NAC) in SMMC-7721 cells. The specific ODC inhibitor difluoromethylornithine (DFMO) increased ROS levels and weakened the ability of sodium nitrite and ammonium chloride mixture in the regulation of invasion of SMMC-7721 cells. These data demonstrated that sodium nitrite and ammonium chloride mixture promote invasion of SMMC-7721 cells by enhancing ROS/ODC pathway.

Sodium nitrite enhanced the potentials of migration and invasion of human hepatocellular carcinoma SMMC-7721 cells through induction of mitophagy / 药学学报

Nitrites play multiple characteristic functions in invasion and metastasis of hepatic cancer cells, but the exact mechanism is not yet known. Cancer cells can maintain the malignant characteristics via clearance of excess mitochondria by mitophagy. The purpose of this article was to determine the roles of nitrite, reactive oxygen species (ROS) and hypoxia inducing factor 1 alpha (HIF-1α) in mitophagy of hepatic cancer cells. After exposure of human hepatocellular carcinoma SMMC-7721 cells to a serial concentrations of sodium nitrite for 24 h under normal oxygen, the maximal cell vitality was increased by 16 mg·L-1 sodium nitrite. In addition, the potentials of migration and invasion for SMMC-7721 cells were increased significantly at the same time. Furthermore, sodium nitrite exposure displayed an increase of stress fibers, lamellipodum and perinuclear mitochondrial distribution by cell staining with Actin-Tracker Green and Mito-Tracker Red, which was reversed by N-acetylcysteine (NAC, a reactive oxygen scavenger). DCFH-DA staining with fluorescent microscopy showed that the intracellular level of ROS concentration was increased by the sodium nitrite treatment. LC3 immunostaining and Western blot results showed that sodium nitrite enhanced cell autophagy flux. Under the transmission electron microscopy (TEM), more autolysosomes formed after sodium nitrite treatment and NAC could prevent autophagosome degradation. RT-PCR results indicated that the expression levels of COXⅠ and COXⅣ mRNA were decreased significantly after sodium nitrite treatment. Meanwhile, laser scanning confocal microscopy showed that sodium nitrite significantly reduced mitochondrial mass detected by Mito-Tracker Green staining. The expression levels of HIF-1α, Beclin-1 and Bnip3 (mitophagy marker molecular) increased remarkably after sodium nitrite treatment, which were reversed by NAC. Our results demonstrated that sodium nitrite (16 mg·L-1) increased the potentials of invasion and migration of hepatic cancer SMMC-7721 cells through induction of ROS and HIF-1α mediated mitophagy.

Sodium nitrite enhanced the potentials of migration and invasion of human hepatocellular carcinoma SMMC-7721 cells through induction of mitophagy / 药学学报

Nitrites play multiple characteristic functions in invasion and metastasis of hepatic cancer cells, but the exact mechanism is not yet known. Cancer cells can maintain the malignant characteristics via clearance of excess mitochondria by mitophagy. The purpose of this article was to determine the roles of nitrite, reactive oxygen species (ROS) and hypoxia inducing factor 1 alpha (HIF-1 α) in mitophagy of hepatic cancer cells. After exposure of human hepatocellular carcinoma SMMC-7721 cells to a serial concentrations of sodium nitrite for 24 h under normal oxygen, the maximal cell vitality was increased by 16 mg x (-1) sodium nitrite. In addition, the potentials of migration and invasion for SMMC-7721 cells were increased significantly at the same time. Furthermore, sodium nitrite exposure displayed an increase of stress fibers, lamellipodum and perinuclear mitochondrial distribution by cell staining with Actin-Tracker Green and Mito-Tracker Red, which was reversed by N-acetylcysteine (NAC, a reactive oxygen scavenger). DCFH-DA staining with fluorescent microscopy showed that the intracellular level of ROS concentration was increased by the sodium nitrite treatment. LC3 immunostaining and Western blot results showed that sodium nitrite enhanced cell autophagy flux. Under the transmission electron microscopy (TEM), more autolysosomes formed after sodium nitrite treatment and NAC could prevent autophagosome degradation. RT-PCR results indicated that the expression levels of COX I and COXIV mRNA were decreased significantly after sodium nitrite treatment. Meanwhile, laser scanning confocal microscopy showed that sodium nitrite significantly reduced mitochondrial mass detected by Mito-Tracker Green staining. The expression levels of HIF-1α, Beclin-1 and Bnip3 (mitophagy marker molecular) increased remarkably after sodium nitrite treatment, which were reversed by NAC. Our results demonstrated that sodium nitrite (16 mg x L(-1)) increased the potentials of invasion and migration of hepatic cancer SMMC-7721 cells through induction of ROS and HIF-1α mediated mitophagy.

Sodium nitrite enhanced the potentials of migration and invasion of human hepatocellular carcinoma SMMC-7721 cells through induction of mitophagy / 药学学报

Nitrites play multiple characteristic functions in invasion and metastasis of hepatic cancer cells, but the exact mechanism is not yet known. Cancer cells can maintain the malignant characteristics via clearance of excess mitochondria by mitophagy. The purpose of this article was to determine the roles of nitrite, reactive oxygen species (ROS) and hypoxia inducing factor 1 alpha (HIF-1 α) in mitophagy of hepatic cancer cells. After exposure of human hepatocellular carcinoma SMMC-7721 cells to a serial concentrations of sodium nitrite for 24 h under normal oxygen, the maximal cell vitality was increased by 16 mg x (-1) sodium nitrite. In addition, the potentials of migration and invasion for SMMC-7721 cells were increased significantly at the same time. Furthermore, sodium nitrite exposure displayed an increase of stress fibers, lamellipodum and perinuclear mitochondrial distribution by cell staining with Actin-Tracker Green and Mito-Tracker Red, which was reversed by N-acetylcysteine (NAC, a reactive oxygen scavenger). DCFH-DA staining with fluorescent microscopy showed that the intracellular level of ROS concentration was increased by the sodium nitrite treatment. LC3 immunostaining and Western blot results showed that sodium nitrite enhanced cell autophagy flux. Under the transmission electron microscopy (TEM), more autolysosomes formed after sodium nitrite treatment and NAC could prevent autophagosome degradation. RT-PCR results indicated that the expression levels of COX I and COXIV mRNA were decreased significantly after sodium nitrite treatment. Meanwhile, laser scanning confocal microscopy showed that sodium nitrite significantly reduced mitochondrial mass detected by Mito-Tracker Green staining. The expression levels of HIF-1α, Beclin-1 and Bnip3 (mitophagy marker molecular) increased remarkably after sodium nitrite treatment, which were reversed by NAC. Our results demonstrated that sodium nitrite (16 mg x L(-1)) increased the potentials of invasion and migration of hepatic cancer SMMC-7721 cells through induction of ROS and HIF-1α mediated mitophagy.