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Background: This research aimed to study the associations between XPD (G751A, rs13181), hOGG1 (C326G, rs1052133) and XRCC4 (G1394T, rs6869366) gene polymorphisms and the risk of colorectal cancer (CRC) in a Chinese Han population. Method: A total of 225 Chinese Han patients with CRC were selected as the study group, and 200 healthy subjects were recruited as the control group. The polymorphisms of XPD G751A, hOGG1 C326G and XRCC4 G1394T loci were detected by the RFLP-PCR technique in the peripheral blood of all subjects. Results: Compared with individuals carrying the XPD751 GG allele, the A allele carriers (GA/AA) had a significantly increased risk of CRC (adjusted OR = 2.109, 95%CI = 1.352-3.287, P=0.003). Similarly, the G allele (CG/GG) of hOGG1 C326G locus conferred increased susceptibility to CRC (adjusted OR = 2.654, 95%CI = 1.915-3.685, P<0.001). In addition, the T allele carriers (GT/TT) of the XRCC4 G1394T locus have an increased risk of developing CRC (adjusted OR = 4.512, 95%CI = 2.785-7.402, P<0.001). The risk of CRC was significantly increased in individuals with both the XPD locus A allele and the hOGG1 locus G allele (adjusted OR = 1.543, 95%CI = 1.302-2.542, P=0.002). Furthermore, individuals with both the hOGG1 locus G allele and the XRCC4 locus T allele were predisposed to CRC development (adjusted OR = 3.854, 95%CI = 1.924-7.123, P<0.001). The risks of CRC in XPD gene A allele carriers (GA/AA) (adjusted OR = 1.570, 95%CI = 1.201-1.976, P=0.001), hOGG1 gene G allele carriers (CG/GG) (adjusted OR = 3.031, 95%CI = 2.184-4.225, P<0.001) and XRCC4 gene T allele carriers (GT/TT) (adjusted OR = 2.793, 95%CI = 2.235-3.222, P<0.001) were significantly higher in patients who smoked ≥16 packs/year. Conclusion: Our results suggest that XPD G751A, hOGG1 C326G and XRCC4 G1394T gene polymorphisms might play an important role in colorectal carcinogenesis and increase the risk of developing CRC in the Chinese Han population. The interaction between smoking and these gene polymorphisms would increase the risk of CRC. [ABSTRACT FROM AUTHOR]

Cervical cancer is the second most common malignancy in women worldwide and always has recurrence owing to radioresistance. MicroRNA (miRNA or miR) has been identified to relate to the sensitivity of cancer radiotherapy. Here, we investigated the potential of miRNA-320 as a biomarker for radiosensitivity by targeting β-catenin in cervical cancer. A radioresistant cervical cancer cell line, C33AR, was established, and the radioresistance of C33AR cells was confirmed by a colony-formation assay. The expression of miRNA-320 was detected by reverse transcription-quantitative polymerase chain reaction, and compared between C33A and C33AR. β-catenin, the target of miRNA-320, was determined at the protein level by western blotting after transfecting the inhibitor of miRNA-320. The expression of miRNA-320 was markedly decreased in C33AR cells, which appeared to be more radioresistant, compared with its parental cell line C33A. Target prediction suggested that miRNA-320 negatively regulated the expression of β-catenin. Knockdown of β-catenin increased C33AR radiosensitivity, which revealed that the inhibition of β-catenin could rescue the miRNA-320-mediated cell radioresistance. On the other hand, overexpressing miRNA-320 increased C33AR radiosensitivity. In conclusion, miRNA-320 regulated the radiosensitivity of C33AR cells by targeting β-catenin. This finding provides evidence that miRNA-320 may be a potential biomarker of radiosensitivity in cervical cancer. [ABSTRACT FROM AUTHOR]

STUDY QUESTION: Do N-acetylglucosaminyltransferase (GnT-V) and N-acetylglucosaminyltransferase III (GnT-III) play an important role in early spontaneous miscarriage (ESM) in humans. SUMMARY ANSWER: The dynamic balance between GnT-V and GnT-III expression in chorionic villi differed between early normal pregnancy and ESM and was associated with altered b1,6-N-acetylglucosamine (b1,6-GlcNAc) and bisecting N-acetylglucosamine (bis-GlcNAc) branched N-glycans on integrin b1. WHAT IS KNOWN ALREADY: GnT-V contributes to metastasis, while GnT-III is recognized as a metastasis suppressor. It has been reported that GnT-V contributes to placentation in the early phase of pregnancy, possibly regulating trophoblast invasion. However, the expressions of GnT-V and GnT-III in ESM have not been reported. STUDY DESIGN, SIZE, DURATION: Villous samples from 6 to 9 weeks of gestation were collected in the First Affiliated Hospital of Chongqing Medical University from May 2013 to September 2014 from 60 normal pregnant women undergoing elective termination of pregnancy and from 40 patients with a clinical diagnosis of ESM. PARTICIPANTS, MATERIALS, SETTING, METHODS: Quantitative PCR and western blots were used to examine the GnT-V and GnT-III mRNA (Mgat5 and Mgat3) and protein expression, respectively, of chorionic villi in both the ESM group and the normal group from week 6 to week 9.We used immunofluorescence and immunohistochemistry to detect the location of GnT-V and GnT-III. Lectin fluorescence and histochemistry were used to test the location of b1,6-GlcNAc and bis-GlcNAc branching in the normal and ESM groups. To assess the functional capacity of GnT-V and GnT-III in the chorionic villi between the two groups, we used an enzyme-linked immunosorbent assay kit to measure the activity of these enzymes. Using co-precipitated integrin α5β1 followed by phytohaemagglutinin (PHA)-L and PHA-E blotting, we investigated whether GnT-V and GnT-III could modify the N-glycosylation profile in terms of the β1,6-GlcNAc and bis-GlcNAc structures in integrin α5β1 during the first trimester in both groups. MAIN RESULTS AND THE ROLE OF CHANCE: In the normal group expression and activity of GnT-V and the concentration of its product, β1,6-GlcNAc were higher at week 9 than at weeks 6, 7 and 8 (P < 0.05). In contrast, the expression and activity of GnT-III and the concentration of its product, bis-GlcNAc were higher at week 6 than at weeks 7, 8 and 9 (P < 0.05). Compared with the normal group, the ESM group exhibited a lower expression of GnT-V and β1,6-GlcNAc (P < 0.05) and a higher expression of GnT-III and bis-GlcNAc (P < 0.05) with consistent changes in enzymatic activity. Immunofluorescence showed that GnT-V was located mainly in the cytoplasm of syncytiotrophoblasts (STBs) and chorionic villous cytotrophoblasts (CTBs), in both the ESM group and the normal group. βb1,6-GlcNAc N-glycan was mainly located outside of the STB and CTB layer in normal villi and was expressed only rarely in the ESM villi. GnT-III was expressed primarily in the cytoplasm of STBs and expressed only very weakly in the CTBs of normal villi, whereas it was highly expressed in both the STBs and CTBs in the ESM group. bis-GlcNAc was primarily located outside of the STBs in the normal villi, whereas it was expressed much more abundantly outside of both the STBs and CTBs in the ESM group at each week of gestation. Moreover, decreased β1,6-GlcNAc-branched N-glycans and increased bis-GlcNAc-branched N-glycans on integrin β1(P < 0.05) were observed in the ESM group. WIDER IMPLICATIONS OF THE FINDINGS: Our findings provide a new insight for studying the mechanism of clinical ESM in humans and it might be valuable for the clinical diagnosis and treatment of ESM. LIMITATIONS, REASONS FOR CAUTION: The study lacks experiments in vitro to disclose the precise mechanism by which GnT-V and GnT-III regulate ESM. In some cases, degradation of the tissues after the miscarriage event cannot be ruled out. study funding/competing interest(s): This study was supported by grants from the National Natural Science Foundation of China (31271546). The authors have no competing interests. [ABSTRACT FROM AUTHOR]

Background The molecular mechanisms underlying the early development of atrial fibrillation (AF) remain poorly understood. Emerging evidence suggests that abnormal epigenetic modulation via microRNAs (miRNAs) might be involved in the pathogenesis of paroxysmal AF (pAF). Objective To identify key molecular changes associated with pAF, we conducted state-of-the-art transcriptomic studies to identify the abnormal miRNA-mRNA interactions potentially driving AF development. Methods High-quality total RNA including miRNA was isolated from atrial biopsies of age-matched and sex-matched pAF patients and control patients in sinus rhythm (SR; n = 4 per group) and used for RNA-sequencing and miRNA microarray. Results were analyzed bioinformatically and validated using quantitative real-time (qRT)-PCR and 3'UTR luciferase reporter assays. Results 113 genes and 49 miRNAs were differentially expressed (DE) in pAF versus SR patients. Gene ontology analysis revealed that most of the DE genes were involved in the "gonadotropin releasing hormone receptor pathway" and "p53 pathway". Of these DE genes, bioinformatic analyses identified 23 pairs of putative miRNA-mRNA interactions that were altered in pAF (involving 15 miRNAs and 17 mRNAs). Using qRT-PCR and 3'UTR luciferase reporter assays, the interaction between upregulation of miR-199a-5p and downregulation of FKBP5 was confirmed in samples from pAF patients. Conclusion Our combined transcriptomic analysis and miRNA microarray study of atrial samples from pAF patients revealed novel pathways and miRNA-mRNA regulations that may be relevant in the development of pAF. Future studies are required to investigate the potential involvement of the gonadotropin releasing hormone receptor and p53 pathways in AF pathogenesis. [ABSTRACT FROM AUTHOR]

Background: The TLR/MyD88 signaling pathway is an important driver of inflammation and cancer and is a possible target for antitumor therapy.Methods: We generated a MyD88 inhibitor (TJ-M2010-5), which was designed to bind to the TIR domain of MyD88 to interfere with its homodimerization, and the TLR/MyD88 signal pathway. We utilized a mouse model of azoxymethane/dextran sodium sulfate (AOM/DSS)-induced colitis-associated cancer (CAC) in combination with TJ-M2010-5 administration to investigate the anti-inflammation-related cancer effect of MyD88 inhibitor in vivo. Data were analyzed with one-way and repeated measures analysis of variance. Differences in survival between groups were compared using the log rank test. All statistical tests were two-sided.Results: TJ-M2010-5 inhibited MyD88 homodimerization in transfected HEK293 cells in a concentration-dependent manner and suppressed MyD88 signaling in LPS-responsive RAW 264.7 cells in vitro. In a 10-week CAC mouse model (n = 30 per group), TJ-M2010-5 treatment statistically significantly reduced AOM/DSS-induced colitis and completely prevented CAC development with less related body mass loss, resulted in 0% mortality of treated mice (compared with 53% mortality of control mice), decreased cell proliferation, and increased apoptosis in colon tissue. TJ-M2010-5 treatment also inhibited production of inflammatory cytokines and chemokines (TNF-α, IL-6,G-CSF, MIP-1β, TGF-β1, IL-11, IL-17A, IL-22 and IL-23) and infiltration of immune cells (macrophages, dendritic cells, neutropihls and CD(+)4 T cells) in colon tissues of mice.Conclusions: Our findings suggest that TLR/MyD88 signaling may be a therapeutic target for CAC intervention and MyD88 inhibitors may be a promising therapeutic modality for treating patients with colitis or CAC. [ABSTRACT FROM AUTHOR]

Lake Chaohu, which is a large, shallow, hypertrophic freshwater lake in southeastern China, has been experiencing lake-wide toxic Microcystis blooms in recent decades. To illuminate the relationships between microcystin (MC) production, the genotypic composition of the Microcystis community and environmental factors, water samples and associated environmental data were collected from June to October 2012 within Lake Chaohu. The Microcystis genotypes and MC concentrations were quantified using quantitative real-time PCR (qPCR) and HPLC, respectively. The results showed that the abundances of Microcystis genotypes and MC concentrations varied on spatial and temporal scales. Microcystis exists as a mixed population of toxic and non-toxic genotypes, and the proportion of toxic Microcystis genotypes ranged from 9.43% to 87.98%. Both Pearson correlation and stepwise multiple regressions demonstrated that throughout the entire lake, the abundances of total and toxic Microcystis and MC concentrations showed significant positive correlation with the total phosphorus and water temperature, suggesting that increases in temperature together with the phosphorus concentrations may promote more frequent toxic Microcystis blooms and higher concentrations of MC. Whereas, dissolved inorganic carbon (DIC) was negatively correlated with the abundances of total and toxic Microcystis and MC concentrations, indicating that rising DIC concentrations may suppress toxic Microcystis abundance and reduce the MC concentrations in the future. Therefore, our results highlight the fact that future eutrophication and global climate change can affect the dynamics of toxic Microcystis blooms and hence change the MC levels in freshwater. [ABSTRACT FROM AUTHOR]

Background: As a pattern recognition receptor, Toll‐like receptor 7 (TLR7) widely presented in the endosomal membrane of various cells. However, the precise role and mechanism of TLR7 in septic cardiomyopathy remain unknown. This study aims to determine the role of TLR7 in cardiac dysfunction during sepsis and explore the mechanism of TLR7 in septic cardiomyopathy. Methods: We generated a mouse model of septic cardiomyopathy by challenging with lipopolysaccharide (LPS). TLR7‐knockout (TLR7−/−), wild‐type (WT) mice, cardiac‐specific TLR7‐transgenic (cTG‐TLR7) overexpression, and littermates WT (LWT) mice were subjected to septic model. Additionally, to verify the role and mechanism of TLR7 in vitro, we transfected neonatal rat ventricular myocytes (NRVMs) with Ad‐TLR7 and TLR7 siRNA before LPS administration. The effects of TLR7 were assessed by Ca2+ imaging, western blotting, immunostaining, and quantitative real‐time polymerase chain reaction (qPCR). Results: We found that TLR7 knockout markedly exacerbated sepsis‐induced systolic dysfunction. Moreover, cardiomyocytes isolated from TLR7−/− mice displayed weaker Ca2+ handling than that in WT mice in response to LPS. Conversely, TLR7 overexpression alleviated LPS‐induced systolic dysfunction, and loxoribine (TLR7‐specific agonist) improved LPS‐induced cardiac dysfunction. Mechanistically, these optimized effects were associated with enhanced the adenosine (cAMP)‐protein kinase A (PKA) pathway, which upregulated phosphorylate‐phospholamban (p‐PLN) (Ser16) and promoted sarco/endoplasmic reticulum Ca2+ ATPase (Serca) and Ryanodine Receptor 2 (RyR2) expression in the sarcoplasmic reticulum (SR), and ultimately restored Ca2+ handling in response to sepsis. While improved Ca2+ handling was abrogated after H89 (a specific PKA inhibitor) pretreatment in cardiomyocytes isolated from cTG‐TLR7 mice. Consistently, TLR7 overexpression improved LPS‐induced Ca2+‐handling decrement in NRVMs. Nevertheless, TLR7 knockdown showed a deteriorative phenotype. Conclusions: Our data demonstrated that activation of TLR7 protected against sepsis‐induced cardiac dysfunction through promoting cAMP‐PKA‐PLN pathway, and we revealed that TLR7 might be a novel therapeutic target to block the septic cardiomyopathy and support systolic function during sepsis. [ABSTRACT FROM AUTHOR]

Sanggenon C (SC), which is a natural flavonoid found in the stem bark of Cortex Mori, has been discovered to have the antioxidant, anti-inflammatory, and antitumor properties. However, its effect in osteoporosis has not yet been reported. In this research, the effect of SC on the proliferation of MC3T3-E1 cells was evaluated by using the MTT assay. Alkaline phosphatase (ALP) activity and the mRNA expression of Runx2, Collagen I, OPG, and RANKL were examined. TRAP-positive cell counting and bone resorption pits were adopted to observe the effect of SC on the formation and function of osteoclasts. Next, the mRNA level of TRAP, CTSK, NFATc1, and TRAF6 of osteoclasts were measured by real-time qPCR. In addition, the anti-osteoporosis activity of SC in vivo was evaluated in the zebrafish model. Our study indicated that SC exhibited a significant stimulatory effect on MC3T3-E1 cell proliferation at 1 to 10 µM and caused an increase in ALP activity at 0.3 to 10 µM. It could upregulate the expression of Runx2, Collagen I, and increases the OPG/RANKL ratio. Furthermore, SC was found to inhibit the formation and function of osteoclasts, which is demonstrated by a lower number of TRAP-positive multinuclear cells and a fewer area of bone resorption pits compared to the control group. TRAP, CTSK, and NFATc1 were downregulated in 0.3 to 10 µM SC treated groups. In addition, 3 to 10 µM SC also inhibited the expression of TRAF6 mRNA. When prednisone-induced zebrafish was treated with 0.3, 1, 3, and 10 µM SC, higher mineralization of vertebrate column was discovered in a dose-dependent pattern, which suggests that SC could reverse the bone loss of zebrafish caused by prednisone. In summary, these findings indicated that SC has the potential to prevent or treat osteoporosis. [ABSTRACT FROM AUTHOR]

Phascolarctobacterium can produce short-chain fatty acids, including acetate and propionate, and can be associated with the metabolic state and mood of the host. The present study investigated the colonization characteristics of Phascolarctobacterium faecium in healthy individuals <1-80 years old in Southern China. A total of 150 fresh fecal samples were collected, and bacterial DNA was isolated from these samples for quantitative polymerase chain reaction analysis. Phascolarctobacterium faecium demonstrated a high colonization rate and abundant colonization in the human gastrointestinal tract. The colonization rate varied between 43.33-93.33%, and the abundance of Phascolarctobacterium faecium ranged between 3.22-5.76 log cells g-1 (<1 years old) and 3.06-9.33 log cells g-1 (>1 year old). The permillage of Phascolarctobacterium faecium in total bacteria ranged between 0.004-1.479. There was presence of Phascolarctobacterium faecium-like bacteria in younger individuals with a gradual increase in the number of bacteria maintained at a high level with increasing ages (between 1 and 60 years old), but with a decrease in elderly individuals (>60 years old). The results of the present study demonstrated that Phascolarctobacterium faecium is abundantly colonized in the human gastrointestinal tract. [ABSTRACT FROM AUTHOR]

Osteoarthritis (OA) is a common cause of functional deterioration in older adults, and altered chondrogenesis is the most common pathophysiological process involved in the development of OA. MicroRNA-145 (miR-145) has been shown to regulate chondrocyte homeostasis. However, the function of miR-145 in OA remains to be elucidated. In the present study, the expression levels of miR-145 were examined in cartilage specimens from 25 patients with knee OA using reverse transcription-quantitative polymerase chain reaction analysis. The effects of miR-145 on the proliferation and fibrosis of the C-20/A4 and CH8 cell lines were also investigated using 3-(4,5-dimethylth-iazol-2-yl)-2,5-diphenyltetrazolium bromide and western blot assays in vitro. The results revealed that the expression of miR-145 was decreased in the OA cartilage tissues, compared with normal cartilage tissues. The overexpression of miR-145 by transfection of cells with miR-145 mimics significantly inhibited C-20/A4 and CH8 cell proliferation and fibrosis. Furthermore, tumor necrosis factor receptor superfamily, member 11b (TNFRSF11B) was identified as a direct target of miR-145 in chondrocytes, which was confirmed using a dual-luciferase reporter assay. The expression level of TNFRSF11B was markedly upregulated in the patients with OA, and the ectopic expression of miR-145 was capable of suppressing the expression of TNFRSF11B. In addition, the knock down of TNFRSF11B using specific small interfering RNA also inhibited the proliferation and fibrosis of C-20/A4 and CH8 cells in vitro. These data provide the first evidence, to the best of our knowledge, to suggest the critical function of miR-145 in regulating the expression of TNFRSF11B, which may have important implications on the regulation of chondrocyte proliferation and fibrosis in OA. [ABSTRACT FROM AUTHOR]

Although interspecific chimeras can be identified using laborious techniques, more accurate and rapid detectable methods need to be established. The present study develops a nested polymerase chain reaction (nPCR) assay to detect human-mouse chimeras. A set of previously validated outer primers, specific to the human SRY gene, was used for conventional one-step PCR, while the inner primers for nPCR were designed. The specificities of PCR and nPCR assays were examined; both primer sets yielded PCR amplification products from male human epidermis-derived mesenchymal stem cell-like pluripotent cell DNA but no amplification products from negative control DNA. The sensitivity of this nPCR was determined using mixed DNA. Measurable amplification of SRY transcripts was a male human to female mouse DNA ratio of 1:10,000. We then tested the nPCR assay on tissues from female mouse chimeras. The nPCR products were selected randomly for sequencing and positive samples were further analyzed by fluorescence in situ hybridization (FISH) using specific probes for the human SRY gene and by immunofluorescence staining for species-specific markers. There was 100% concordance among nPCR, FISH, and immunofluorescence results, and the nPCR product sequences were consistent with the human SRY gene. Taken together, we developed a new, highly specific, sensitive, and reliable method to detect human-mouse chimeras. [ABSTRACT FROM AUTHOR]

STUDY QUESTION Can avian influenza A (H7N9) virus be transmitted between unrelated individuals in a hospital setting? METHODS An epidemiological investigation looked at two patients who shared a hospital ward in February 2015, in Quzhou, Zhejiang Province, China. Samples from the patients, close contacts, and local environments were examined by real time reverse transcriptase (rRT) polymerase chain reaction (PCR) and viral culture. Haemagglutination inhibition and microneutralisation assays were used to detect specific antibodies to the viruses. Primary outcomes were clinical data, infection source tracing, phylogenetic tree analysis, and serological results. STUDY ANSWER AND LIMITATIONS A 49 year old man (index patient) became ill seven days after visiting a live poultry market. A 57 year old man (second patient), with a history of chronic obstructive pulmonary disease, developed influenzalike symptoms after sharing the same hospital ward as the index patient for five days. The second patient had not visited any poultry markets nor had any contact with poultry or birds within 15 days before the onset of illness. H7N9 virus was identified in the two patients, who both later died. Genome sequences of the virus isolated from both patients were nearly identical, and genetically similar to the virus isolated from the live poultry market. No specific antibodies were detected among 38 close contacts. Transmission between the patients remains unclear, owing to the lack of samples collected from their shared hospital ward. Although several environmental swabs were positive for H7N9 by rRT-PCR, no virus was cultured. Owing to delayed diagnosis and frequent hospital transfers, no serum samples were collected from the patients, and antibodies to H7N9 viruses could not be tested. WHAT THIS STUDY ADDS Nosocomial H7N9 transmission might be possible between two unrelated individuals. Surveillance on patients with influenza-like illness in hospitals as well as chickens in live poultry markets should be enhanced to monitor transmissibility and pathogenicity of the virus. FUNDING, COMPETING INTERESTS, DATA SHARING Funding support from the Program of International Science and Technology Cooperation of China (2013DFA30800), Basic Work on Special Program for Science and Technology Research (2013FY114600), National Natural Science Foundation of China (81402730), Special Program for Prevention and Control of Infectious Diseases in China (2013ZX10004218), US National Institutes of Health (1R01-AI108993), Zhejiang Province Major Science and Technology Program (2014C03039), and Quzhou Science and Technology Program (20111084). The authors declare no other interests and have no additional data. [ABSTRACT FROM AUTHOR]

In an attempt to elucidate the effects of different CO2 concentrations (270, 380, and 750 μL/L) on the competition of microcystin-producing (MC-producing) and non-MC-producing Microcystis strains during dense cyanobacteria blooms, an in situ simulation experiment was conducted in the Meiliang Bay of Lake Taihu in the summer of 2012. The abundance of total Microcystis and MC-producing Microcystis genotypes was quantified based on the 16S rDNA and mcyD gene using real-time PCR. The results showed that atmospheric CO2 elevation would significantly decrease the pH value and increase the dissolved inorganic carbon (DIC) concentration. Changes in CO2 concentration did not show significant influence on the abundance of total Microcystis population. However, CO2 concentrations may be an important factor in determining the subpopulation structure of Microcystis. The enhancement of CO2 concentrations could largely increase the competitive ability of non-MC-producing over MC-producing Microcystis, resulting in a higher proportion of non-MC-producing subpopulation in treatments using high CO2 concentrations. Concurrently, MC concentration in water declined when CO2 concentrations were elevated. Therefore, we concluded that the increase of CO2 concentrations might decrease potential health risks of MC for human and animals in the future. [ABSTRACT FROM AUTHOR]