BACKGROUND:Previous studies have found that neuronal damage caused by continuous excessive fluoride exposure is related to Ca2+overload,but the mechanism of Ca2+flow conversion between intracellular calcium stores and cell apoptosis damage is still unclear.OBJECTIVE:To investigate the effect of fluoride exposure on Ca2+transport channel proteins and apoptosis levels in the mitochondria-associated endoplasmic reticulum membrane of primary cultured neural cells.METHODS:Primary nerve cells of neonatal SD rats were cultured in vitro and identified by immunofluorescence staining with neuronal nucleus-specific antibody up to day 7.The nerve cells were divided into control group(containing 0 mmol/L sodium fluoride),low fluoride group(containing 0.5 mmol/L sodium fluoride),and high fluoride group(containing 1 mmol/L sodium fluoride).The cell morphological changes were observed by light microscope 24 hours after fluorine exposure.The expression levels of apoptosis-related protein BAX/BCL-2 and calcium transfer-related pathways VDAC1,GRP 75,and IP3R were detected using western blot assay.The expression levels of VDAC1,GRP 75,and IP3R mRNA were detected by RT-PCR.Ca2+levels were detected by Rhood-2AM Ca2+probe.Mitochondrial membrane potential detection kit was used to detect the change in mitochondrial membrane potential.The level of apoptosis was determined by flow cytometry and TUNEL staining.RESULTS AND CONCLUSION:(1)The purity of neurons cultured on day 7 had been determined to be over 90％,with few impurities,good growth status,and tight cell network connections,meeting the requirements of subsequent experiments.(2)Compared with the control group,growth of neural cell clusters in the low-fluoride group and the high-fluoride group increased;the processes were broken;the cell body was rounded,and the connection network between cells was destroyed.Compared with the low-fluoride group,the cell damage changes in the high-fluoride group were more obvious.(3)Compared with the control group,the protein expressions of VDAC1,GRP75,and IP3R were increased in the low-fluoride group and the high-fluoride group(P＜0.05),and the ratio of apoptosis-related protein BAX/BCL-2 was increased(P＜0.05).Compared with the control group,the expression of VDAC1 and GRP75 mRNA in the low-fluoride group was significantly increased(P＜0.05);the expression levels of VDAC1,GRP75,and IP3R mRNA in the high-fluoride group were significantly increased(P＜0.01).(4)The level of cell apoptosis increased significantly after fluoride exposure,and the high-fluoride group was significantly higher than the control and low-fluoride groups(P＜0.01).(5)After fluoride exposure,the concentration of mitochondrial Ca2+in nerve cells increased significantly(P＜0.05),the mitochondrial membrane potential decreased(P＜0.01),and the degree of damage in the high-fluoride group was more obvious(P＜0.05).The results show that fluoride exposure impairs the morphological structure of primary neural cells,resulting in upregulation of Ca2+transfer pathway protein expression between the endoplasmic reticulum and mitochondria,mitochondrial Ca2+overload,mitochondrial damage,and increased levels of apoptosis.

BACKGROUND:Previous studies have found that neuronal damage caused by continuous excessive fluoride exposure is related to Ca2+overload,but the mechanism of Ca2+flow conversion between intracellular calcium stores and cell apoptosis damage is still unclear.OBJECTIVE:To investigate the effect of fluoride exposure on Ca2+transport channel proteins and apoptosis levels in the mitochondria-associated endoplasmic reticulum membrane of primary cultured neural cells.METHODS:Primary nerve cells of neonatal SD rats were cultured in vitro and identified by immunofluorescence staining with neuronal nucleus-specific antibody up to day 7.The nerve cells were divided into control group(containing 0 mmol/L sodium fluoride),low fluoride group(containing 0.5 mmol/L sodium fluoride),and high fluoride group(containing 1 mmol/L sodium fluoride).The cell morphological changes were observed by light microscope 24 hours after fluorine exposure.The expression levels of apoptosis-related protein BAX/BCL-2 and calcium transfer-related pathways VDAC1,GRP 75,and IP3R were detected using western blot assay.The expression levels of VDAC1,GRP 75,and IP3R mRNA were detected by RT-PCR.Ca2+levels were detected by Rhood-2AM Ca2+probe.Mitochondrial membrane potential detection kit was used to detect the change in mitochondrial membrane potential.The level of apoptosis was determined by flow cytometry and TUNEL staining.RESULTS AND CONCLUSION:(1)The purity of neurons cultured on day 7 had been determined to be over 90％,with few impurities,good growth status,and tight cell network connections,meeting the requirements of subsequent experiments.(2)Compared with the control group,growth of neural cell clusters in the low-fluoride group and the high-fluoride group increased;the processes were broken;the cell body was rounded,and the connection network between cells was destroyed.Compared with the low-fluoride group,the cell damage changes in the high-fluoride group were more obvious.(3)Compared with the control group,the protein expressions of VDAC1,GRP75,and IP3R were increased in the low-fluoride group and the high-fluoride group(P＜0.05),and the ratio of apoptosis-related protein BAX/BCL-2 was increased(P＜0.05).Compared with the control group,the expression of VDAC1 and GRP75 mRNA in the low-fluoride group was significantly increased(P＜0.05);the expression levels of VDAC1,GRP75,and IP3R mRNA in the high-fluoride group were significantly increased(P＜0.01).(4)The level of cell apoptosis increased significantly after fluoride exposure,and the high-fluoride group was significantly higher than the control and low-fluoride groups(P＜0.01).(5)After fluoride exposure,the concentration of mitochondrial Ca2+in nerve cells increased significantly(P＜0.05),the mitochondrial membrane potential decreased(P＜0.01),and the degree of damage in the high-fluoride group was more obvious(P＜0.05).The results show that fluoride exposure impairs the morphological structure of primary neural cells,resulting in upregulation of Ca2+transfer pathway protein expression between the endoplasmic reticulum and mitochondria,mitochondrial Ca2+overload,mitochondrial damage,and increased levels of apoptosis.

Background The residues of pharmaceutical and personal care products (PPCPs) in aquatic environments have become an increasingly prominent urban pollution issue, attracting widespread attention. The analysis of PPCPs pollution in water environments holds profound implications in Zhengzhou, a strategically important city in central China. Objective To analyze the pollution characteristics of PPCPs, such as antidepressants and antibiotics, in rivers of Zhengzhou and assess associated ecological risk. Methods Water samples were collected from three rivers of Zhengzhou, and 13 PPCPs (5 antibiotics and 8 antidepressants) were analyzed quantitatively by high performance liquid chromatography-triple quadrupole mass spectrometry (HPLC-MS/MS) after automatic solid phase extraction. Risk quotient (RQ) was applied to assess ecological risk of PPCPs with high concentration. Results The primary antibiotics pollutants were norfloxacin and ofloxacin, both with a detection rate of 100%. Among antidepressants, venlafaxine and citalopram showed the highest detection rates at 92.3% and 88.5%, respectively. The detected antibiotics with the highest average concentrations included ofloxacin and sulfamethoxazole with concentrations of 99.8 ng·L⁻¹and 96.2 ng·L⁻¹, respectively, while antidepressants venlafaxine and citalopram were detected with the highest average concentrations of 15.2 ng·L⁻¹and 1.35 ng·L⁻¹, respectively. The inter-river comparisons revealed statistically significant differences in contaminant loads (P<0.05). The sums of average PPCP concentrations at sampling points in the Jialu River and Suoxu River were 83.4 ng·L⁻¹ and 100.4 ng·L⁻¹, respectively. The Xiaoqing River exhibited higher pollution levels than both the Jialu and Suoxu Rivers, with a total average concentration of 478.4 ng·L⁻¹, where ofloxacin and sulfamethoxazole were identified as the predominant pollutants. The results of ecological risk assessment indicated the RQ contributed by sulfamethoxazole ranged between 0.50−0.95 in the Xiaoqing River, suggesting a controllable risk but requiring prioritized mitigation strategies. The RQ values of norfloxacin were distributed within the range of 0.10-0.30, indicating a moderate ecological risk. The RQ values for ofloxacin and venlafaxine remained below 0.10, indicating a lower risk level. Conclusion PPCPs contamination is positive in the rivers of Zhengzhou, and sulfamethoxazole and ofloxacin are the primary cantaminants. The Xiaoqing River exhibits the highest pollution levels. The initial risk assessment show that sulfamethoxazole and norfloxacin pose potential ecological risks, requiring prioritized contamination management.

Objective: This article was to evaluate the applicability and feasibility of "Lingnanzhun" -an "Internet Plus-based HIV Self-testing Tool" targeting MSM in Guangzhou. Hopefully, the results could be used to improve the existing HIV testing services and to support the implementation and scale-up of HIV self-testing programs. Methods: Data were collected from a survey on HIV testing preferences among the Internet-using MSM in April to June, 2015. Univariate and multivariate logistic regression analysis were applied to identify factors associated with the use of HIV self-testing service provided by Lingnanzhun. Information related to the users of Lingnanzhun during September 2014 and December 2018 was also collected. Results: 769 MSM were recruited as participants. Of them, age distribution was 16-77(28.6±6.8) years old, 88.3%(679/769) were unmarried, 42.2%(325/769) were registered residents of Guangzhou, 82.1%(631/769) had university or college education. Among them, 195 (25.4%) used the HIV self- testing program of Lingnanzhun while 574 (74.6%) using the clinic service. Compared with the clinic service users, the Lingnanzhun users showed the following characteristics: longer experience in the MSM community ≥10 years (32.8% vs. 20.9%, 64/195 vs. 120/574); having male casual sexual partners ≥2 (42.1% vs. 29.6%, 82/195 vs. 170/574); having group sex (6.2% vs. 2.6%, 12/195 vs. 15/574) and having commercial sex with men (13.8% vs. 3.0%, 27/195 vs. 17/574). Data from the Lingnanzhun users showed that a total of 3 000 users had practised 5 038 times of self HIV-testings. 11.4% (343/3 000) of the Lingnanzhun users had never been tested. Conclusions It was applicable and feasible to provide Internet-based HIV self-testing service to MSM as a significant complement to the traditional facility-based HIV testing services. It was also useful in accessing those who were having higher risk or had never received HIV testing so as to increase the testing uptake and the frequency.

OBJECTIVE To investigate the effect ofγ-secretase inhibitor N-[N-(3,5-difluorophen?acetyl)-L-alanyl]-S-phenylglycine t-butyl ester(DAPT)on phenotypic transformation and matrix accu?mulation induced by aristolochic acid(AA) in renal tubular epithelial cells(NRK-52E)and explore the mechanism. METHODS NRK-52E cells were divided stochastically into normal cell control group,AA 10 mg·L-1 group and AA 10 mg·L-1+DAPT 1 and 10μmol·L-1 group. After 24 h,the mRNA expressions of Notch1,Jagged1,Numb,E-cadherin,transforming growth factor-β1(TGF-β1),α-smooth muscle actin(α-SMA),bone morphogenic protein 7 (Bmp7),typeⅠ a1 (Col1a1) and Ⅲ collagens a1 (Col3a1)were quantified by quantitative real-time RT-PCR. The protein expressions of Notch1,Jagged1,α-SMA,and Col3a1 in NRK-52E cel s were detected by immunofluorescence staining. RESULTS In NRK-52E cells,AA enhanced the expression of TGF-β1,α-SMA and Col3a1 mRNA(P<0.05),reduced the expression of E-cadherin mRNA(P<0.05),up-regulated the mRNA expression of Notch1 mRNA(P<0.01)and Jagged1(P<0.05),and down-regulated the mRNA expression of Numb mRNA(P<0.05) compared with normal cell control group,indicating that phenotypic transformation and matrix accumu?lation occurred in AA-treated NRK-52E cells,accompanied by activated Notch signaling. Treatment with DAPT inhibited Notch signaling by decreasing the expression of Notch1 and Jagged1 (P<0.05),and increasing the expression of Numb mRNA(P<0.05). Furthermore, DAPT also down-regulated the expression levels of TGF-β1,α-SMA,Col1a1 and Col3a1 mRNA(P<0.05), and up-regulated the expression level of Bmp7 and E-cadherin mRNA(P<0.05) compared with AA group,suggesting that DAPT inhibited phenotypic transformation and matrix accumulation in AA-treated NRK-52E cells. CONCLUSION AA induces phenotypic transformation and matrix accumulation in renal tubular epithelial cells,which is inhibited by DAPT treatment. The possible mechanism is that DAPT suppresses the activation of Notch signaling,resulting in the reduction of epithelial-to-mesenchymal transition and matrix deposition.

Objective To introduce the development strategy of“Internet Plus”AIDS prevention services and its implementation results from 2010 to 2015 in Guangzhou, China. Methods A gay men's health column was created for an active website aimed at men who have sex with men (MSM), in collaboration with local community organizations and the Guangzhou CDC. We designed intervention tools (including scenario-based applications and HIV risk self-assessment systems) and an online HIV testing service platform, integrated with applied psychology and behavioral theory as well as the“Internet Plus”concept, to intervene in HIV infection risk factors among MSM. Data of clients who accessed the“Internet Plus”AIDS services from 2010 to 2015 were used to evaluate service operation. Six-year consecutive surveys, conducted between April and July of each service year, were collected using a national AIDS sentinel surveillance questionnaire. For each year of surveillance, information on HIV prevalence, HIV interventions received during the past year, unprotected anal intercourse in the past 6 months, and HIV testing in the past year were compared using the chi-squared (χ2) test, to roughly reflect the effect of“Internet Plus”AIDS prevention services. Results As of 31 December 2015, a total of 34 395 MSM had received“Internet Plus”services and HIV testing. The number of MSM tested increased from 2 338 in 2010 to 8 054 in 2015. From 2010 to 2015, newly identified HIV cases in each year were 59, 166, 312, 283, 291, and 270, which accounted for 25.0%, 32.8%, 38.8%, 35.1%, 30.5%, and 23.2% of MSM HIV cases of Guangzhou, respectively. Sentinel surveillance data showed that during the study period, 3 047 MSM were investigated, with 405, 400, 401, 633, 608, and 600 each year, respectively. The proportion of participants who had received any HIV intervention during the past year was 74.3% (301), 70.8% (283), 83.3% (334), 85.0%(538), 69.1%(420), and 83.8%(503) each year, respectively (trend χ2=6.53, P=0.011). HIV testing done during the past year accounted for 44.0%(178), 44.3%(177), 49.4%(198), 53.4%(338), 56.1%(341), and 60.2%(361) each year, respectively (trendχ2=40.83, P<0.001). Unprotected anal intercourse in the past 6 months accounted for 59.3% (240), 62.0% (248), 56.6% (227), 57.0% (361), 48.4% (294), and 43.7%(262) each year, respectively (trend χ2=42.21, P<0.001). Conclusion The“Internet Plus”AIDS prevention services in this study represent a manner to enhance traditional HIV prevention strategies. We found these services to be effective in implementation of the national AIDS control and prevention strategy, especially for the expansion of intervention, testing, and case identification among high-risk populations.

Objective To introduce the development strategy of“Internet Plus”AIDS prevention services and its implementation results from 2010 to 2015 in Guangzhou, China. Methods A gay men's health column was created for an active website aimed at men who have sex with men (MSM), in collaboration with local community organizations and the Guangzhou CDC. We designed intervention tools (including scenario-based applications and HIV risk self-assessment systems) and an online HIV testing service platform, integrated with applied psychology and behavioral theory as well as the“Internet Plus”concept, to intervene in HIV infection risk factors among MSM. Data of clients who accessed the“Internet Plus”AIDS services from 2010 to 2015 were used to evaluate service operation. Six-year consecutive surveys, conducted between April and July of each service year, were collected using a national AIDS sentinel surveillance questionnaire. For each year of surveillance, information on HIV prevalence, HIV interventions received during the past year, unprotected anal intercourse in the past 6 months, and HIV testing in the past year were compared using the chi-squared (χ2) test, to roughly reflect the effect of“Internet Plus”AIDS prevention services. Results As of 31 December 2015, a total of 34 395 MSM had received“Internet Plus”services and HIV testing. The number of MSM tested increased from 2 338 in 2010 to 8 054 in 2015. From 2010 to 2015, newly identified HIV cases in each year were 59, 166, 312, 283, 291, and 270, which accounted for 25.0%, 32.8%, 38.8%, 35.1%, 30.5%, and 23.2% of MSM HIV cases of Guangzhou, respectively. Sentinel surveillance data showed that during the study period, 3 047 MSM were investigated, with 405, 400, 401, 633, 608, and 600 each year, respectively. The proportion of participants who had received any HIV intervention during the past year was 74.3% (301), 70.8% (283), 83.3% (334), 85.0%(538), 69.1%(420), and 83.8%(503) each year, respectively (trend χ2=6.53, P=0.011). HIV testing done during the past year accounted for 44.0%(178), 44.3%(177), 49.4%(198), 53.4%(338), 56.1%(341), and 60.2%(361) each year, respectively (trendχ2=40.83, P<0.001). Unprotected anal intercourse in the past 6 months accounted for 59.3% (240), 62.0% (248), 56.6% (227), 57.0% (361), 48.4% (294), and 43.7%(262) each year, respectively (trend χ2=42.21, P<0.001). Conclusion The“Internet Plus”AIDS prevention services in this study represent a manner to enhance traditional HIV prevention strategies. We found these services to be effective in implementation of the national AIDS control and prevention strategy, especially for the expansion of intervention, testing, and case identification among high-risk populations.

AIM:To investigate the effect of cyclopamine on Hedgehog (HH) signaling, phenotypic transfor-mation and matrix accumulation induced by aristolochic acid (AA) in renal tubular epithelial cell NRK-52E.METHODS:NRK-52E cells were randomly divided into control group (treated with solvent only), AA group (treated with AA at con-centrations of 1, 5, 10 mg/L) and cyclopamine group (treated with AA at concentration of 10 mg/L plus cyclopamine at concentrations of 1, 5, 10μmol/L).After cultured for 24 h, the mRNA expression of Ptch1, Smo,α-SMA, E-cadherin, ZO-1, BMP-7, type I collagen and type III collagen was quantified by real-time PCR.The protein levels of Shh and TGF-β1 were detected by ELISA .Immunofluorescence staining was used to evaluate the expression of Ptch 1, Smo,α-SMA, E-cadherin and type III collagen in the NRK-52E cells.RESULTS: AA increased the expression of TGF-β1, α-SMA and type III collagen, decreased the expression of E-cadherin and ZO-1 protein, and down-regulated the expression of Ptch1, Shh and Smo mRNA in the NRK-52E cells, indicating that AA activated HH signaling , and phenotypic transformation and matrix accumulation occurred in AA-treated NRK-52E cells.Treatment with cyclopamine inhibited HH signaling by decrea-sing Smo expression and increasing Ptch 1 expression.Moreover, cyclopamine also down-regulated the expression of TGF-β1,α-SMA, type I collagen and III collagen , and up-regulated the expression of BMP-7, ZO-1 and E-cadherin.CON-CLUSION:AA induces phenotypic transformation and matrix accumulation in renal tubular epithelial cells , which can be inhibited by cyclopamine treatment .The possible mechanism is that cyclopamine suppresses the activation of HH signaling , resulting in the reduction of epithelial-to-mesenchymal transition and matrix deposition .

OBJECTIVE To investigate the molecular mechanisms of resveratrol( Res)in renal interstitial fibrosis(RlF)in rats with unilateral ureteral obstruction(UUO). METHODS Forty-eight Spra-gur-Dawley rats were randomly divided into UUO( normal saline,n = 16),UUO with Res treatment (Res,20 mg·kg-1 ,n=16),and sham-operation(sham,n=16)models. The kidneys were excised on the 7th and 14th day. The deposition of collagen fiber in the kidney was detected with HE and Masson staining. The levels of sonic hedgehog(SHH,an inducer of SHH pathway)in kidney tissues were deter-mined by ELlSA. lmmunohistochemical analysis was performed to evaluate the protein expression of SHH signaling-related molecules,including SHH,smoothened(Smo),patched-1(Ptch1),and Gli1, proliferating cell nuclear antigen(PCNA)and matrix component typeⅢ collagen. The mRNA expression levels of Smo,Ptch1 and Gli1 were detected by real-time RT-PCR. RESULTS The degree of RlF observed with HE and Masson staining was obviously increased in UUO kidneys,but decreased in Res-treated kidneys. Enhanced expression levels of typeⅢ collagen and PCNA in UUO rats were suppressed by Res treatment(P﹤0.05). Res administration decreased the expression levels of SHH,Smo,and Gli1 (P﹤0.05),but increased the expression of Ptch1(P﹤0.05),suggesting that Res inhibit the obstruction-induced activation of SHH signaling. CONCLUSION Res can attenuate RlF in UUO rats,and the possi-ble mechanism is that Res down-regulates the activity of SHH signaling and inhibits cellular proliferation, resulting in inhibition of matrix accumulation in renal interstitium of UUO rats.

Objective To investigate the expression of monocyte-macrophage-related factors and interstitial fibrosis in kidney tissues of rats with ureter obstruction and recanalization .Methods Forty-eight male Spragur-Dawley rats were divided randomly into the obstructive group:sham (n=6), unilateral ureteral obstruction(UUO)3 days (n=6), UUO 7 days (n=6), and UUO 14 days (n=6) and recanalization group:bilateral ureteral obstruction(RBUO)0 day (n=6), 3 days after RBUO (n=6), 7 days after RBUO (n=6), and 14 days after RBUO (n=6).The kidneys were excised on day 3, 7, and 14, and the deposition of collagen fibers in kidney was detected with HE and Masson staining . Immunohistochemical analysis was performed to evaluate the protein expressions of monocyte chemoattractant protein -1 (MCP-1), macrophage colony-stimulating factor (M-CSF) and activated-macrophage marker CD68.Real-time PCR was used to detect the mRNA expressions of MCP-1 and M-CSF.TGF-β1 levels were determined by ELISA .Results Fibrosis observed with HE and Masson staining was obviously increased in kidney tissue of UUO rats , and aggravated as time prolonged, but alleviated in rats with recanalization .TGF-β1 levels were increased obviously in the UUO group , but decreased in rats with recanalization compared with those in BUO rats .In UUO rats, mRNA and protein expression levels of MCP-1 and M-CSF were increased .MCP-1 and M-CSF expression was gradually decreased in rats with recanalization compared with those in BUO rats .The dynamic change in expression of MCP-1 and M-CSF in both UUO rats and recanalization rats was consistent with the change in expression of CD 68. Conclusion Dynamic change in expression of MCP-1 and M-CSF in kidney tissues reflects change of activated and accumulated monocyte -macrophages , which may be one of the major mechanisms contributing to fibrosis induced by ureter obstruction .Renal fibrosis is alleviated by down-regulated expression of monocyte-macrophages factors with recanalization operation .