Effectiveness of eHealth interventions for HIV prevention, testing and management: An umbrella review.

BACKGROUND: Human immunodeficiency virus (HIV) infection has become a major contributor to the global burden of disease. Globally, the number of cases of HIV continues to increase. Electronic health (eHealth) interventions have emerged as promising tools to support disease self-management among people living with HIV. The purpose of this umbrella review is to systematically evaluate and summarize the evidence and results of published systematic reviews and meta-analyses on the effectiveness of eHealth interventions for HIV prevention, testing and management. METHODS: PubMed, Embase and the Cochrane Library were searched for reviews. The methodological quality of the included studies was assessed using AMSTAR-2. RESULTS: A total of 22 systematic reviews were included. The methodological quality of the reviews was low or critically low. EHealth interventions range from Internet, computer, or mobile interventions to websites, programs, applications, email, video, games, telemedicine, texting, and social media, or a combination of them. The majority of the reviews showed evidence of effectiveness (including increased participation in HIV management behaviours, successfully changed HIV testing behaviours, and reduced risk behaviours). EHealth interventions were effective in the short term. CONCLUSIONS: Ehealth interventions have the potential to improve HIV prevention, HIV testing and disease management. Due to the limitations of the low methodological quality of the currently available systematic reviews, more high-quality evidence is needed to develop clear and robust recommendations.

Short-Chain Acyl-CoA Dehydrogenase as a Therapeutic Target for Cardiac Fibrosis.

Cardiac fibrosis is considered as unbalanced extracellular matrix (ECM) production and degradation, contributing to heart failure. Short-chain acyl-CoA dehydrogenase (SCAD) negatively regulates pathological cardiac hypertrophy. The purpose of this study was to investigate the possible role of SCAD in cardiac fibrosis. In-vivo experiments were performed on spontaneously hypertensive rats (SHR) and SCAD knockout mice. The cardiac tissues of hypertensive patients with cardiac fibrosis were used for measurement of SCAD expression. In-vitro experiments, with angiotensin II (Ang II), SCAD siRNA and adenovirus-SCAD (Ad-SCAD) were performed using cardiac fibroblasts (CFs). SCAD expression was significantly decreased in the left ventricles of SHR. Notably, swim training ameliorated cardiac fibrosis in SHR in association with the elevation of SCAD. The decrease in SCAD protein and mRNA expression levels in SHR CFs were in accordance with those in the left ventricular myocardium of SHR. In addition, SCAD expression was downregulated in CFs treated with Ang II in vitro, and SCAD siRNA interference induced the same changes in cardiac fibrosis as Ang II-treated CFs, while Ad-SCAD treatment significantly reduced the Ang II-induced CFs proliferation, α-SMA and collagen expression. In SHR infected with Ad-SCAD, the cardiac fibrosis of the left ventricle was significantly decreased. On the other hand, cardiac fibrosis occurred in conventional SCAD knockout mice. SCAD immunofluorescence intensity of cardiac tissue in hypertensive patients with cardiac fibrosis was lower than that of healthy subjects. All together, the current experimental outcomes indicate that SCAD has a negative regulatory effect on cardiac fibrosis and support its potential therapeutic target for suppressing cardiac fibrosis.

Effects of aerobic exercise or Tai Chi Chuan interventions on problematic mobile phone use and the potential role of intestinal flora: A multi-arm randomized controlled trial.

BACKGROUND: Problematic use of mobile phones (PMPU) has been described as a serious public health issue. METHODS: This study was a parallel three-arm randomized controlled trial and has completed registration (ClinicalTrials.gov Identifier: NCT05843591). Ninety college students with PMPU were randomly assigned to the aerobic exercise group (AE group, n = 30), the Tai Chi Chuan group (TCC group, n = 30), or the wait-list control group (WLC group, n = 30). At the end of the intervention, stool samples from the study participants were collected for biological analysis based on 16 S rDNA amplicon sequencing technology. The primary outcome was addiction symptoms assessed by the Smartphone Addiction Scale-Short Version (SAS-SV). The secondary outcomes are emotional symptoms, physical symptoms, and flora species. RESULTS: Compared with the WLC group, the AE and TCC groups showed reductions in PMPU levels, physical and mental fatigue, but there was no difference between the two groups. Moreover, the effect of increasing self-esteem embodied in the TCC group was not present in the AE group. Compared to the WLC group, the relative abundance of Bacteroidaceae and Bacteroides were lower in the AE group, while the relative abundance of Erysipelotrichaceae and Alistipes were lower in the TCC group. And the relative abundance of Bacteroidaceae, Bacteroides, and Alistipes were significantly and negatively correlated with the decline in PMPU scores. CONCLUSION: AE or TCC is an effective, safe and efficient intervention for college students with PMPU, providing some physiological and psychological benefits and having some impact on their intestinal flora.

Pre-Exposure Prophylaxis Care Continuum for HIV Risk Populations: An Umbrella Review of Systematic Reviews and Meta-Analyses.

Pre-exposure prophylaxis (PrEP) is an effective biomedical strategy for HIV prevention. This umbrella review is aimed at providing a comprehensive summary of the current status of each stage of the PrEP care cascade. A systematic literature search was conducted in PubMed, Embase, and Cochrane. Additionally, a Measurement Tool to Assess Systematic Reviews 2 (AMSTAR-2) tool and Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) checklist were used to evaluate their methodological and reporting quality, respectively. A total of 30 systematic reviews met the inclusion criteria. According to the results of methodological quality assessment, 3 reviews were rated as low, while 27 as critically low. Furthermore, the results of the reporting quality evaluation revealed a mean score of 23.03 for the included reviews. Across all the reviews, awareness of PrEP was generally moderate in all populations, and the acceptability was even higher compared with awareness. Unfortunately, the PrEP uptake among different groups was even less optimal, although the adherence was almost above moderate, and several barriers that hindered the utilization of PrEP were identified, and the most common are as follows: cost, stigma, lack of knowledge, mistrust, low risk perception, and more. Although PrEP has proven to be an effective prevention method to date, the promotion of PrEP failed to achieve the anticipated outcome. To reinforce the generalization of and use of PrEP, and effectively control HIV transmission, it is urgent to identify the underlying causes of low uptake rates so that efficient interventions can be implemented.

FTZ polysaccharides ameliorate kidney injury in diabetic mice by regulating gut-kidney axis.

BACKGROUND: The Fufang-zhenzhu-tiaozhi formula (FTZ), a traditional Chinese medicine (TCM) commonly used to treat metabolic diseases, potentially impacts the microbial ecosystem. Increasing evidence suggests that polysaccharides, bioactive components of TCMs, have great potential on kinds of diseases such as DKD by regulating intestinal flora. PURPOSE: This study aimed to investigate whether the polysaccharide components in FTZ (FTZPs) have beneficial effects in DKD mice via the gut-kidney axis. STUDY DESIGN AND METHODS: The DKD model in mice was established by streptozotocin combined with a high-fat diet (STZ/HFD). Losartan was used as a positive control, and FTZPs were administered at doses of 100 and 300 mg/kg daily. Renal histological changes were measured by H&E and Masson staining. Western blotting, quantitative real-time polymerase chain reaction (q-PCR) and immunohistochemistry were performed to analyze the effects of FTZPs on renal inflammation and fibrosis, which were further confirmed using RNA sequencing. Immunofluorescence was used to analyze the effects of FTZPs on colonic barrier function in DKD mice. Faecal microbiota transplantation (FMT) was used to evaluate the contribution of intestinal flora. 16S rRNA sequencing was utilized to analyze the composition of intestinal bacteria, and UPLC-QTOF-MS-based untargeted metabolomics was used to identify the metabolite profiles. RESULTS: Treatment with FTZPs attenuated kidney injury, as indicated by the decreased urinary albumin/creatinine ratio and improved renal architecture. FTZPs downregulated the expression of renal genes associated with inflammation, fibrosis, and systematically blunted related pathways. FTZPs also restored the colonic mucosal barrier and increased the expression of tight junction proteins (E-cadherin). The FMT experiment confirmed the substantial contribution of the FTZPs-reshaped microbiota to relieving DKD symptoms. Moreover, FTZPs elevated the content of short-chain fatty acids (propionic acid and butanoic acid) and increased the level of the SCFAs transporter Slc22a19. Intestinal flora disorders caused by diabetes, including the growth of the genera Weissella, Enterococcus and Akkermansia, were inhibited by FTZPs treatment. Spearman's analysis revealed that these bacteria were positively correlated with indicators of renal damage. CONCLUSION: These results show that oral administration of FTZPs, by altering SCFAs levels and the gut microbiome, is a therapeutic strategy for the treatment of DKD.

Longitudinal association between problematic smartphone use and sleep disorder among Chinese college students during the COVID-19 pandemic.

BACKGROUND: Problematic smartphone use (PSU) and sleep disorders (SD) are common public health problems among college students. While previous cross-sectional studies have found a relationship between PSU and SD, the causal direction of this relationship remains unclear. This study aims to examine the longitudinal changes of PSU and SD during the COVID-19 pandemic, determine the causal relationship between them, and identify confounding factors that affect this association. METHODS: The study sample consisted of 1186 Chinese college students (47.7% male) with a mean age of 18.08 years. Participants completed the Smartphone Addiction Scale - Short Version (SAS-SV) and the Pittsburgh Sleep Quality Index (PSQI) at both baseline and follow-up surveys, conducted one year apart. The cross-lagged panel model (CLPM) was used to examine the causal relationship between PSU and SD, stratified by gender and duration of daily physical activity. The fixed effect panel regression was used to confirm the findings of CLPM. RESULTS: The results of the CLPM analysis showed a significant bidirectional relationship between PSU and SD for the overall sample, which was consistent with the fixed effects model findings. However, subgroup analyses revealed that the bidirectional association disappeared among males or those who engaged in daily physical activity for more than 1 h. CONCLUSIONS: Our study shows a significant bidirectional association between PSU and SD, with variations across gender and daily physical activity levels. Encouraging physical activity may serve as a potential intervention to disrupt the bidirectional association between PSU and SD, which has important implications for public health strategies aimed at reducing the negative consequences of PSU and SD.

Effects of exercise or tai chi on Internet addiction in college students and the potential role of gut microbiota: A randomized controlled trial.

OBJECTIVE: This study aimed to explore the effect of exercise or tai chi on Internet addiction disorder (IAD) among college students and clarified the abundance and population changes of gut microbiota in different groups. Thus explore the potential role of gut microbiota between exercise and IAD. METHODS: A total of 93 subjects diagnosed with mild IAD were randomly assigned to the exercise group, the tai chi group, and the control group. The intervention groups received exercise or tai chi for 8 weeks and the control group was evaluated without any intervention. Fecal samples were collected after the intervention. RESULTS: 1) Analysis found a significant intervention effect with the exercise group showing an average decrease of 8.84 points on the Internet addiction test (IAT) compared with the control group (95%CI -15.41 to-2.27, P = 0.004). But there was no significant difference between the control group and the tai chi group. 2) Both exercise (P = 0.018) and tai chi (P = 0.026) could significantly relieve fatigue symptoms. 3) The relative abundance of the Betaproteobacteria, Porphyromonadaceae, Sutterellaceae, and Alistipes were significantly decreased in the exercise group compared with the control group, and the relative abundance of Escherichia was significantly increased in the exercise group. 4) The relative abundance of Betaproteobacteria, Sutterellaceae, and Escherichia had significant differences between the improved group and the no-improved group. CONCLUSION: Exercise intervention has a considerable effect on treating IAD. Exercise and tai chi might have effectiveness in relieving the symptoms of fatigue. Exercise intervention regulates the gut microflora and changes the abundance of microflora to improve IAD. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, identifier NCT05529368.

A bidirectional association between smartphone addiction and depression among college students: A cross-lagged panel model.

Background: Smartphone addiction (SA) is associated with adverse consequences, especially for freshmen. Evidence indicates that SA is associated with depression, and it is necessary to conduct a longitudinal study to explore the association further. Methods: SA (measured by the Smartphone Addiction Scale-Short Version) and depression (measured by the Zung's Self-Rating Depression Scale) among 1,186 freshmen were surveyed at baseline and a respective 12-month follow-up for each participant. The application of a cross-lagged panel model approach (CLPM) revealed an association between SA and depression after adjusting for demographic variables. Results: The CLPM results showed a significant path from baseline SA to follow-up depression (ß = 0.08, P < 0.001) and a significant path from baseline depression to follow-up SA (ß = 0.08, P < 0.001). Compared with the overall cross-lagged model, the cross-lagged coefficient of the path from baseline SA to follow-up depression increased in the female group (ß = 0.10, P = 0.015), and the cross-lagged coefficient of the path from baseline depression to follow-up SA also increased significantly (ß = 0.15, P < 0.001). In contrast, the cross-lagged model in the male group showed no predictive effect between SA and depression (P > 0.05). Conclusions: The current study showed a significant bidirectional association between smartphone addiction and depression among freshmen, but only in the female population.

Association between mobile phone addiction, sleep disorder and the gut microbiota: a short-term prospective observational study.

Bidirectional communication between the gut microbiota and the brain has sparked interest in exploring the link between mobile phone addiction (MPA) and sleep disorders (SD) in microbiome research. However, investigating the role of gut microbiota in this relationship using animal models presents challenges due to the unique nature of MPA, and human research in this area is scarce. We recruited 99 healthy college students to evaluate the gut microbiome using 16S rRNA gene amplicon sequencing and assess MPA and SD at baseline and after a two-month follow-up. Multiple covariate-adjusted statistical models, including linear regression, permutational multivariate analysis of variance and so on, were employed to determine microbiome associations with MPA at baseline and changes in SD at follow-up. Our findings revealed negative associations between MPA and three alpha diversity metrics, along with alterations in bacterial composition. MPA showed negative associations with the relative abundance of Bacteroidetes, while displaying positive associations with Actinobacteria and Bifidobacteriales. Conversely, Actinobacteria exhibited a negative association with increased SD. This study has established a significant link between MPA and a decrease in the alpha diversity of the gut microbiota. Actinobacteria was associated with MPA and SD, respectively. Additional investigation is needed to fully comprehend the relationship between comorbid behavioral disorders and the gut microbiota.

Human CYP2E1-activated mutagenicity of dioxin-like PCBs 105 and 118-Experimental data consistent with molecular docking results.

Polychlorinated biphenyls (PCBs) are persistent organic pollutants with human carcinogenicity. Many lower chlorinated and non-dioxin-like PCBs have been observed to be mutagenic following activation by human CYP2E1, while activation of dioxin-like (DL-) PCBs by this enzyme has never been evidenced. In this study, each DL-PCB was analyzed by molecular docking to human CYP2E1 protein for predicting a substrate interaction. All compounds demonstrated high affinities with the active site of human CYP2E1, binding energy being -8.7 ∼ -9.7 kcal/mol. However, most compounds demonstrated ligand-heme distances as ≥ 6.8 Å, while the values for 2,3,3',4,4'- (PCB 105) and 2,3',4,4',5-pentachlorobiphenyl (PCB 118) were 5.3 and 5.4 Å, respectively (valid for electron transfer). Experimentally, both PCB 105 and 118 induced micronuclei in a V79-derived cell line engineered for expression of human CYP2E1 at low micromolar concentrations, while inactive or weakly positive in V79-Mz control cells; these effects were blocked or reduced by 1-aminobenzotriazole, a suicide CYP inhibitor. However, DL-PCBs 77, 81 and 126 were all negative in both cell lines. In a human hepatoma (C3A) cell line, PCB 105 and 118 induced micronuclei marginally, while with ethanol pretreatment (to stabilize CYP2E1) both compounds induced micronuclei efficiently, and co-exposure to trans-1,2-dichloroethylene (a selective CYP2E1 inhibitor) led to clearly negative results with both compounds. Finally, both PCB 105 and 118 induced PIG-A gene mutations in C3A cells, which was blocked by trans-1,2-dichloroethylene. In summary, in silico and experimental results consistently suggest that DL- PCBs 105 and 118 may be activated by human CYP2E1 for mutagenic activities.

Protective effect of Tenuifolin against Alzheimer's disease.

Amyloid-ß (Aß) plays a critical role in the pathogenesis of Alzheimer's disease (AD), an age-related neurodegenerative ailment. Emerging evidence suggests that Tenuifolin (TEN) significantly decreases Aß secretion and relieves cellular inflammatory responses. However, the mechanism of this activity has not been fully elucidated. In the present study, we investigate the effect of TEN on autophagy, a process that plays an important role in the generation and metabolism of Aß, in the presence or absence of the autophagy inhibitor 3-MA. The obtained results show that TEN prevents Aß25-35-induced inflammation and decreases Aß1-40 and Aß1-42 levels by decreasing BACE1 in SH-SY5Y cells. Moreover, TEN decreases the mRNA levels of BACE1 but has no impact on the gene expressions of amyloid precursor proteins (APP). 3-MA, the most widely used autophagy inhibitor, reverses the effects of TEN in Aß25-35-induced SH-SY5Y cells. The association between TEN and autophagy was further investigated by examining the levels of autophagy markers LC3 II and Beclin 1, as well as the protein levels of mTOR, AMPK, and ULK1. The results showed that TEN increases LC3 II, Beclin 1, and mTOR, inhibits the degradation of AMPK, and increases the expression of ULK1. This suggests that TEN protects against Aß25-35-induced cellular inflammation in an AD cell model through the regulation of autophagy, which, in part, is mediated by the activation of the AMPK/mTOR/ULK1 pathway.

Mutagenic Activity of N-Nitrosodiethylamine in Cell Lines Expressing Human CYP2E1-Adequacy of Dimethylsulfoxide as Solvent.

Human CYP2E1 metabolizes many xenobiotics of low-molecular weight, thereby activating various promutagens/procarcinogens. In toxicological studies in vitro, dimethylsulfoxide (DMSO) is a common vehicle for organic compounds. However, it was observed to potently inhibit CYP2E1 activity. We were interested in whether it affects CYP2E1-dependent mutagenic responses. In this study, N-nitrosodiethylamine (NDEA), which is soluble in both water and DMSO, was used as a model promutagen. It induced Hprt gene mutations and micronuclei in a Chinese hamster V79-derived cell line expressing both human CYP2E1 and sulfotransferase (SULT) 1A1 (V79-hCYP2E1-hSULT1A1) even at low-micromolar concentrations, but was inactive in parental V79 cells. Mutagenicity of NDEA was also observed in a recombinant V79-hCYP2E1 cell line that expresses human CYP2E1 at a lower level. NDEA induced micronuclei in human L-02 hepatocytes which expressed CYP2E1 even more weakly. DMSO did not modify NDEA-induced gene mutations or micronuclei, up to 0.2% (v:v, the highest noncytotoxic concentration) in V79-hCYP2E1-hSULT1A1 cells. In parental V79-Mz cells, NDEA induced micronuclei with Aroclor 1254-induced rat liver S9 mix, and this effect was unaffected by DMSO up to 0.2%. However, it inhibited the effect of NDEA in L-02 (by 44%) and V79-hCYP2E1 cells (by 70%) at 0.2%, with the effects of NDEA remaining statistically significant. No effect of DMSO was observed on CYP2E1 protein expression in V79-hCYP2E1-hSULT1A1 or its mRNA transcripts in each cell line. We conclude that DMSO may not significantly affect CYP2E1-dependent mutagenic effects, at concentrations up to 0.2% in cells with relatively high CYP2E1 expression. Environ. Mol. Mutagen. 60:214-226, 2019. © 2018 Wiley Periodicals, Inc.

Downregulation of Glutathione S-transferase A1 suppressed tumor growth and induced cell apoptosis in A549 cell line.

Glutathione S-transferase A1 (GSTA1) is a phase II detoxification enzyme and serves a crucial role in anti-cancer drug resistance. In our previous study, GSTA1 was identified to be highly expressed in various subtypes of non-small-cell lung cancer cell lines compared with human embryonic lung fibroblast cell line MRC-5. The aim of the present study was to investigate the effect of GSTA1 expression on the proliferation and apoptosis of A549 cells. GSTA1 expression was knocked down or with overexpressed using lentivirus particles. Western blot analysis and reverse transcription-quantitative polymerase chain reaction (RT-qPCR) were used to assess the protein, and mRNA levels of GSTA1 in A549 cells, respectively. The effect of GSTA1 manipulation on cell proliferation and apoptosis were investigated in vitro using MTT assays, Hoechst 33258 staining and flow cytometry, and in vivo using A549 cell line xenografts in nude mice. The results of the western blot analysis and RT-qPCR revealed that stable cell models of GSTA1 knockdown, and overexpression were established. The data of the MTT assay indicated that the downregulation of GSTA1 significantly inhibited cell proliferation compared with si-control-transfected cells. These si-GSTA1 A549 cells exhibited typical morphological changes of apoptosis, including chromatin condensation and shrunken nuclei compared with the si-control counterparts. An AnnexinV-fluorescein isothiocyanate assay verified that the downregulation of GSTA1 significantly induced cell apoptosis in vitro. In addition, overexpression of GSTA1 significantly promoted tumor growth in vivo. Accordingly, downregulation of GSTA1 suppressed tumor growth. In conclusion, GSTA1 plays an important role in regulation of cell proliferation and cell apoptosis in A549 cell line.

Genistein protects against Aß25-35 induced apoptosis of PC12 cells through JNK signaling and modulation of Bcl-2 family messengers.

BACKGROUND: Deposition of aggregated amyloid beta (Aß) protein is hallmark of Alzheimer's disease, leading to dysfunction and apoptosis of neurons. The isoflavone phytoestrogen compound genistein (Gen) exerts a significant protective effect against Aß25-35 induced neurotoxicity and mitochondrial damage in rat pheochromocytoma (PC12) cells. However, the mechanisms underlying Gen's rescue remain elusive. Therefore we endeavored to research further the molecular mechanisms underlying Gen's inhibition of Aß25-35 induced apoptosis of neurons. RESULTS: We found that Gen dramatically suppressed the activation by Aß25-35 of p-c-Jun N-terminal kinase (p-JNK), and also inhibited the JNK-dependent decreased of Bcl-w and increased of Bim. Furthermore, Gen significantly reduced the cytoplasmic concentrations of cytochrome c and Smac protein as well as caspase-3 activity. Additionally, pretreatment with JNK inhibitor SP600125 effectively suppressed Aß25-35 induced PC12 cell cytotoxicity. CONCLUSION: Taken together, the results suggested that Gen protects PC12 cells from Aß25-35 induced neurotoxicity by interfering with p-JNK activation, thus attenuating the JNK-dependent apoptosis through the mitochondrial pathway. These findings constitute novel insights into the pathway for Aß25-35 toxicity, and the neuroprotective action of Gen.

Potent mutagenicity of some non-planar tri- and tetrachlorinated biphenyls in mammalian cells, human CYP2E1 being a major activating enzyme.

Polychlorinated biphenyls (PCBs) have been classified as human carcinogens. Mutagenicity of lower chlorinated biphenyls as well as activation of transcription factors by some other congeners may contribute to the carcinogenicity of PCBs. Recently, we reported that human CYP2E1 activates mono- and dichlorobiphenyls to mutagens. However, mutagenicity of other PCBs and the involvement of other CYPs remained unknown. In this study, Chinese hamster V79-derived cell lines genetically engineered for expression of individual human CYP enzymes and a human hepatocyte (L-02) line endogenously expressing various CYPs were used to determine the activities of several tri- and tetrachlorobiphenyls to induce micronuclei and gene mutations. 2,3,4'-Trichlorobiphenyl, 2,3,3'-trichlorobiphenyl, 2,4,4',5-tetrachlorobiphenyl and 2,2',5,5'-tetrachlorobiphenyl efficiently induced micronuclei and/or gene mutations in V79-derived cells at low micromolar concentrations, depending on human CYP2E1, while they were inactive in parental V79-Mz cells and weakly positive or inactive in V79-derived cells expressing human CYP1A1, 1A2, 1B1 or 3A4. The induction of gene mutations in human CYP2E1-expressing V79 cells by 2,3,4'-trichlorobiphenyl and 2,4,4',5-tetrachlorobiphenyl was more potent than that of N-nitrosodimethylamine, a strong carcinogen activated by CYP2E1. As representative PCB compounds, 2,3,3'-trichlorobiphenyl and 2,3,4'-trichlorobiphenyl induced micronuclei in L-02 cells, and this effect was blocked by specific CYP2E1 inhibition, wherein the effects of benzo[a]pyrene and aflatoxin B1 (activated by some CYPs other than CYP2E1) were unaffected. This study demonstrates that some non-planar tri- and tetrachlorobiphenyls are potent mutagens in mammalian cells-more potent than previously tested mono- and dichlorobiphenyls-and that among several human CYP enzymes, CYP2E1 is most efficient in activating these environmental contaminants.

Human CYP2E1-dependent mutagenicity of mono- and dichlorobiphenyls in Chinese hamster (V79)-derived cells.

Polychlorinated biphenyls (PCBs) are a group of persistent organic pollutants with confirmed carcinogenicity to humans. Metabolic activation of lower chlorinated PCBs to genotoxic metabolites may involve hydroxylation and further oxidation, and some hydroxylated metabolites may be sulfo-conjugated. However, the genotoxicity of individual PCB compounds is largely unknown. In this study, 15 mono- and dichlorobiphenyls were investigated for genotoxicity using the micronucleus and Hprt mutagenicity assays in a Chinese hamster V79-derived cell line expressing both human cytochrome P450 (CYP) 2E1 and human sulfotransferase (SULT) 1A1 (V79-hCYP2E1-hSULT1A1). All tested compounds were inactive in both assays in V79 control cells. However, eight dichlorobiphenyls strongly induced micronuclei and other congeners were weakly positive for this endpoint in V79-hCYP2E1-hSULT1A1 cells. The effects of each PCB in V79-hCYP2E1-hSULT1A1 cells were abolished or reduced in the presence of a CYP2E1 inhibitor (1-aminobenzotriazole), or enhanced by pretreatment of the cells with (CYP2E1-inducing) ethanol, while the genotoxicity was not significantly affected by a SULT1 inhibitor (pentachlorophenol). As representative dichlorobiphenyls, PCB 5, 10, 8 and 11 (2,3-, 2,5-, 2,4'- and 3,3'-dichlorobiphenyl, respectively) strongly induced Hprt gene mutations in V79-hCYP2E1-hSULT1A1 cells in a concentration-dependent manner. This is the first indication that human CYP2E1 is capable of converting a series of dichlorobiphenyls to strong mutagens.

[Clinical study of modified Gow-Gates technique of inferior alveolar nerve block in impacted mandibular third molar extraction].

PURPOSE: To introduce a minimally invasive and more effective technique of inferior alveolar nerve block. METHODS: Two hundred and six patients who needed extraction of the impacted mandibular third molar were divided randomly into 2 groups: the experimental group (105 cases) with modified Gow-Gates technique (modified Gow-Gates group) and the control group (101 cases) with Halstead technique (Halstead group). The anesthetic success rates, effects and complications were recorded and analyzed with SPSS17.0 software package. RESULTS: The anesthetic success rate was 97.15% in modified Gow-Gates group and 89.10% in Halstead group with significant difference between the 2 groups (P=0.038<0.05); In comparing the anesthesia grade, the ration of grade A and B accounted for 90.48% in modified Gow-Gates group and 87.13% in Halstead group (P=0.446>0.05). Modified Gow-Gates group had much fewer of complications than Halstead group (P=0.014<0.05). CONCLUSIONS: Modified Gow-Gates technique is a minimally invasive and more effective technique for inferior alveolar nerve block anesthesia. Supported by Science and Technology Planning Project of Yueqing City (2014y027).

Growth responses of two tall fescue cultivars to Pb stress and their metal accumulation characteristics.

Tall fescue (Festuca arundinacea), a widely planted cool-season turfgrass and forage, is tolerant to heavy metals. However, previous investigation demonstrated that different accessions varied in Pb tolerance. In present study, hydroponic system was used to study the effects of Pb on two tall fescue cultivars, Pb tolerant 'Silverado' and Pb sensitive 'AST7001', respectively. The results indicated that Pb concentration was 14 times lower in shoots of 'Silverado' (1.34 mg g(-1) dry weight) versus 'AST7001' (19.92 mg g(-1) dry weight), although it was higher in roots of 'Silverado' (68.28 mg g(-1) dry weight) versus 'AST7001' (48.7 mg g(-1) dry weight), when subjected to 1,000 mg L(-1) Pb. In both cultivars, Pb caused an induction in malondialdehyde (MDA) content, to a less increase in 'Silerado' than 'AST7001'. Pb treatment decreased significantly soluble protein content in 'AST7001'. By contrast, soluble protein content was increased progressively, and the ratio of variable to maximal chlorophyll fluorescence was not affected in 'Silverado'. Pb treated tall fescue leaves had a greater level of superoxide dismutase (SOD) and guaiacol peroxidase (POD) activity in both cultivars, however, increase was sharp in 'Silverado' plants. The results of Q-PCR analysis for genes encoding antioxidant enzyme were in accordance with that of enzyme activities. The higher Pb tolerance of 'Silverado' might be attributed to lower shoot Pb concentration and MDA content. Meantime, the amount of soluble protein, activity of SOD and POD, as well as the level of up regulation of Cyt Cu/ZnSOD was all higher in 'Silverado' than in 'AST7001'.

The effect of genistein on the content and activity of α- and ß-secretase and protein kinase C in Aß-injured hippocampal neurons.

Genistein (Gen), a derivative of soy isoflavone aglycone, has been shown to exert significant protective effect on Aß-induced neurotoxicity and neuroinjury. However, its underlying mechanism remains elusive. The objective was to investigate the inhibitory effect of Gen on Aß-induced neurotoxicity and to elucidate the underlying mechanism. Primary rat hippocampal neurons were pre-treated with Gen for 2 hr followed by incubation with Aß 25-35 for an additional 24 hr. The cell viability was assessed by MTT assay. The content and activity of α-, ß-secretase and protein kinase C (PKC) were measured, and the antagonistic effect of PKC inhibitor Myr was also analysed to clarify the molecular mechanism of Gen inhibition of Aß-induced toxicity to hippocampal neurons. The results showed that pre-treatment with Gen significantly increased the cell viability and presented the best effect at the final concentration of 0.375 µg/mL. Gen increases the activity of α-secretase but down-regulates the ß-secretase activity. It also enhances the expression and activity of PKC. Myr, a PKC inhibitor, partially blocks the activation effect of Gen. Gen exerts protective effect on Aß-induced neurotoxicity via activating the PKC signalling pathway, which further regulates the activities of α- and ß-secretase and thereby inhibits the formation and toxicity of Aß.

Mechanism of isoflavone aglycone's effect on cognitive performance of senescence-accelerated mice.

This study investigated the effect of isoflavone aglycone (IA) on the learning and memory performance of senescence-accelerated mice, and explored its neural protective mechanism. Results showed that SAM-P/8 senescence-accelerated mice treated with IA performed significantly better in the Y-maze cognitive test than the no treatment control (P<0.05). The cortex AchE activity, serum SOD and GSH-Px activities were notably higher (P<0.05). MDA concentration and the ß-secretase activity in the hippocampal tissue were both lower (P<0.05). Additionally, the number of hippocampal neurons was increased and cell morphology was significantly improved. Data suggested that IA could indirectly increase concentration of the cholinergic neural transmitter Ach through regulation of AchE, therefore improving the central cholinergic function and enhancing the learning and memory ability. By reducing the ß-secretase activity, IA could decrease the formation and deposition of insoluble Adebris, relieve the resulted toxicity and damage to neurons, and thereby effectively protect the nervous system.