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2.
Rev Sci Instrum ; 95(3)2024 Mar 01.
Article in English | MEDLINE | ID: mdl-38535483

ABSTRACT

The simulator is an indispensable device for the study of high-altitude electromagnetic pulse (HEMP) effects. In order to improve the quality of the electric field waveforms of the HEMP simulator, we carried out simulation and experimental studies for the biconical-wire grid antenna. A new bicone-wire grid antenna HEMP simulator was designed by using skeletonized cones instead of solid cones, which can substantially improve the mobility of the simulator. The effects of different aspect ratios and different cone structures of the simulator on the waveform and distribution characteristics of the electric field were analyzed. The accuracy of the simulation results was verified by testing the bicone-wire grid antenna simulator with the new structure. The results obtained are as follows: First, the simulator can provide a HEMP environment compliant with the International Electrotechnical Commission (IEC) standard in an area of 5 × 6 × 2 m3. Second, the simulator possesses optimal waveform quality and working space among simulators with different aspect ratios. Finally, the influence of using skeletonized cones instead of solid cones on the simulator's electric field waveforms is negligible, and the mobility of the new simulator is significantly improved compared to the original simulator.

3.
Environ Res ; 247: 118274, 2024 Apr 15.
Article in English | MEDLINE | ID: mdl-38246298

ABSTRACT

The existing literature has extensively examined the impact of green innovations, such as patents, on pollution and carbon emissions. However, there has been comparatively less emphasis on the debt financing of green innovation by using patents as collateral. This oversight may have implications for the realization of pollution and carbon emissions reduction goals. Using a natural experiment based on the patent pledge pilot policy in China, this study investigates the impact of patent pledge on pollution and carbon emissions. We find that a significant reduction in the emissions of sulfur dioxide and carbon dioxide attributable to the patent pledge pilot policy, particularly in cities with lower initial green patent rates, and these results still hold after an array of robustness checks. We show that the encouragement of green innovation and the stimulation of environmental entrepreneurship are the mechanisms underlying these emission reduction effects. Furthermore, our analysis indicates that the impact of patent pledges on emission reduction is more pronounced in cities characterized by higher levels of government-reported environmental concern, public engagement in environmentally related searches, pollution information transparency indices, and green development evaluation indices.


Subject(s)
Carbon Dioxide , Environmental Pollution , China , Cities , Government
5.
PeerJ ; 11: e15193, 2023.
Article in English | MEDLINE | ID: mdl-37073275

ABSTRACT

Background: Diabetes and thyroid dysfunction are two closely related endocrine diseases. Increasing evidences show that gut microbiota plays an important role in both glucose metabolism and thyroid homeostasis. Meanwhile, copy number variation (CNV) of host salivary α-amylase gene (AMY1) has been shown to correlate with glucose homeostasis. Hence, we aim to characterize the gut microbiota and CNV of AMY1 in type 2 diabetes (T2D) patients with or without subclinical hypothyroidism (SCH). Methods: High-throughput sequencing was used to analyze the gut microbiota of euthyroid T2D patients, T2D patients with SCH and healthy controls. Highly sensitive droplet digital PCR was used to measure AMY1 CN. Results: Our results revealed that T2D patients have lower gut microbial diversity, no matter with or without SCH. The characteristic taxa of T2D patients were Coriobacteriales, Coriobacteriaceae, Peptostreptococcaceae, Pseudomonadaceae, Collinsella, Pseudomonas and Romboutsia. Meanwhile, Escherichia/Shigella, Lactobacillus_Oris, Parabacteroides Distasonis_ATCC_8503, Acetanaerobacterium, Lactonifactor, uncultured bacterium of Acetanaerobacterium were enriched in T2D patients with SCH. Moreover, serum levels of free triiodothyronine (FT3) and free thyroxine (FT4) in T2D patients were both negatively correlated with richness of gut microbiota. A number of specific taxa were also associated with clinical parameters at the phylum and genus level. In contrast, no correlation was found between AMY1 CN and T2D or T2D_SCH. Conclusion: This study identified characteristic bacterial taxa in gut microbiota of T2D patients with or without SCH, as well as the taxa associated with clinical indices in T2D patients. These results might be exploited in the prevention, diagnosis and treatment of endocrine disorders in the future.


Subject(s)
Diabetes Mellitus, Type 2 , Gastrointestinal Microbiome , Hypothyroidism , Humans , Gastrointestinal Microbiome/genetics , Diabetes Mellitus, Type 2/complications , DNA Copy Number Variations
6.
Medicine (Baltimore) ; 101(34): e30218, 2022 Aug 26.
Article in English | MEDLINE | ID: mdl-36042591

ABSTRACT

OBJECTIVE: Although several studies have identified an association between the rs4784227-cancer susceptibility candidate gene 16 (CASC16) polymorphism and breast cancer, the results remain inconclusive. Therefore, we conducted a meta-analysis to assess the relationship between the rs4784227-CASC16 polymorphism and breast cancer risk. METHODS: Studies were searched in the PubMed, Web of Science, Embase, Google Scholar, and Cochran Library databases until June 10, 2021, to identify all potential literature on rs4784227-CASC16 polymorphism and breast cancer risk association. Fixed-effect or random-effect models were used to calculate odds ratios (ORs) and their corresponding 95% confidence intervals (95% CIs). Subgroup analyses, publication bias, and sensitivity analyses were also conducted. RESULTS: Seventeen eligible studies involving 34,719 subjects (18,445 cases and 16,274 healthy controls) from 7 articles were included in the current meta-analysis. The pooled ORs regarding the association between the rs4784227-CASC16 polymorphism and breast cancer risk were statistically significant [T vs C: OR = 1.244, 95% CI = 1.202-1.287; TT vs CT + CC: OR = 1.407, 95% CI = 1.296-1.528; CC vs CT + TT: OR = 0.777, 95% CI = 0.745-0.811; TT vs CC: OR = 1.544, 95% CI = 1.419-1.681; CT vs CC: OR = 1.244, 95% CI = 1.189-1.301]. On subgroup analysis, the rs4784227-CASC16 T/C gene has a certain correlation with breast cancer susceptibility in Asian and North American populations, but no significant risk in the Australian population. CONCLUSION: Our pooled analysis showed a significant association between the rs4784227- (T) allele and breast cancer susceptibility in Asian and North American populations, and intervention with this mutation might be a new therapeutic strategy for breast cancer. However, large-scale and well-designed studies are needed in different populations to further evaluate the role of the rs4784227-CASC16 polymorphism in breast cancer.


Subject(s)
Breast Neoplasms , Genetic Predisposition to Disease , Neoplasm Proteins , Asian People , Australia , Breast Neoplasms/genetics , Female , Humans , Neoplasm Proteins/genetics , North America , Polymorphism, Single Nucleotide
7.
Polymers (Basel) ; 14(12)2022 Jun 12.
Article in English | MEDLINE | ID: mdl-35745961

ABSTRACT

Fused filament fabrication (FFF) additive manufacturing technology has the advantages of being low cost, having a simple operation, using wide types of molding materials, and producing less pollution during the printing process. However, the mechanical properties of the molded sample are unsatisfactory due to the limited bonding force between the filaments during the forming process, which limits its further development and application in the engineering field. Herein, the hybrid additive manufacturing technology for heterogeneous materials based on the ultrasonic-assisted enhanced fused filament fabrication technology was proposed. The mechanism of ultrasonic vibration on the strengthening of FFF samples was explored. The influence mechanisms of bonding time and ultrasonic strengthening times, ultrasonic strengthening and static load compression on the strengthening of mechanical properties of the sample were investigated. The effects of the thickness and printing angle of the FFF samples on the ultrasonic-enhanced mechanical properties were explored. The tensile strength of the one-time ultrasonic-strengthened sample is up to 43.43 MPa, which is 16.12% higher than that of the original. The maximum bending strength of the four-time ultrasonic-strengthened sample is 73.38 MPa, which is 78.98% higher than that of the original. Ultrasonic strengthening not only re-fused the pores inside the sample, but also improved the bond strength between the rasters. With the increase in the thickness of the sample, the increase rate of ultrasonic to the strength of the sample decreased significantly. The effects of ultrasound on the interlayer adhesion of samples with various printing angles were different. Based on the systematic research on the influence mechanism of ultrasonic process parameters and molding process parameters on the strengthening of FFF, a molding method for additively manufacturing heterogeneous material parts while strengthening the mechanical properties of FFF samples was proposed, and the influence mechanisms of the molding process on the mechanical properties and shape memory properties of the sample were explored, which can broaden the application of FFF technology in the engineering field.

8.
Hum Cell ; 34(3): 759-770, 2021 May.
Article in English | MEDLINE | ID: mdl-33575967

ABSTRACT

Liver fibrosis is a chronic liver injury that leads to liver cirrhosis and liver cancer. Ring finger protein 20 (RNF20), also named as E3 ubiquitin-protein ligase BRE1A, has been reported to be involved in chronic liver diseases. However, the role of RNF20 in liver fibrosis remains unclear. To mimic liver fibrosis in vitro, LX-2 cells were treated with TGF-ß. Gene and protein expressions were detected by RT-qPCR and western blot, respectively. The mechanism by which RNF20 mediated the progression of liver fibrosis was explored by bioinformatics analysis. Finally, in vivo mouse model of liver fibrosis was established to detect the function of RNF20. The results indicated that TGF-ß-induced increase of cell viability and migration was significantly reversed by RNF20 overexpression. Consistently, overexpression of RNF20 significantly reversed TGF-ß-induced activation of fibrotic proteins in LX-2 cells. Meanwhile, VEGFA, TNF-α and IL-6 were found to be the downstream targets of RNF20 in LX-2 cells. Moreover, RNF20 overexpression notably inhibited the progression of liver fibrosis via ubiquitination of H2B. Finally, RNF20 upregulation significantly attenuated the symptom of liver fibrosis in vivo. In summary, overexpression of RNF20 significantly inhibited the progression of liver fibrosis in vitro and in vivo. Therefore, RNF20 might serve as a new target for the treatment of liver fibrosis.


Subject(s)
Gene Expression/genetics , Gene Expression/physiology , Histones/metabolism , Liver Cirrhosis/genetics , Liver Cirrhosis/prevention & control , Lysine/metabolism , Ubiquitin-Protein Ligases/genetics , Ubiquitin-Protein Ligases/metabolism , Ubiquitination/genetics , Cell Movement/drug effects , Cell Movement/genetics , Cell Survival/drug effects , Cell Survival/genetics , Cells, Cultured , Disease Progression , Humans , Interleukin-6/metabolism , Liver Cirrhosis/pathology , Transforming Growth Factor beta/pharmacology , Tumor Necrosis Factor-alpha/metabolism , Ubiquitin-Protein Ligases/physiology , Vascular Endothelial Growth Factor A/metabolism
9.
Front Genet ; 12: 730920, 2021.
Article in English | MEDLINE | ID: mdl-35493265

ABSTRACT

Background: RAC1 is involved in the progression of HCC as a regulator, but its prognostic performance and the imbalance of immune cell infiltration mediated by it are still unclear. We aim to explore the prognostic and immune properties of RAC1 in HCC. Methods: We separately downloaded the data related to HCC from the Cancer Genome Atlas (TCGA) and GEO database. CIBERSORT deconvolution algorithm, weighted gene co-expression network analysis (WGCNA) and LASSO algorithm participate in identifying IRGs and the construction of prognostic signatures. Results: The study discovered that RAC1 expression was linked to the severity of HCC lesions, and that its high expression was linked to a poor prognosis. Cox analysis confirmed that RAC1 is a clinically independent prognostic marker. M0, M1 and M2 macrophages' abundance are significantly different in HCC. We found 828 IRGs related to macrophage infiltration, and established a novel 11-gene signature with excellent prognostic performance. RAC1-based risk score and M0 macrophage has a good ability to predict overall survival. Conclusion: The immune state of irregular macrophage infiltration may be one of the precursors to carcinogenesis. The RAC1 correlated with M0 macrophage and the risk score to show a good performance to predict the survival of HCC patients.

10.
OMICS ; 23(3): 167-179, 2019 03.
Article in English | MEDLINE | ID: mdl-30883302

ABSTRACT

Chronic hepatitis B (CHB) is a major global health burden. Liver fibrosis, an insidious process, is the main histopathological change in CHB that might lead to the end-stage liver disease if left untreated. The intermediate liver fibrosis (S2) is the optimal time to start antiviral therapy. The aim of the present study was to examine the proteomic changes in patients with CHB at different fibrotic stages, with a view to identify future serum biomarkers for S2. Ninety CHB patients were grouped into mild (S0-1), intermediate (S2), and severe liver fibrosis (S3-4) (61 men and 29 women; age 25-63 years). Isobaric tagging for relative and absolute quantitation was applied to screen proteins differentially expressed among the patient groups. Another 46 patients with CHB (age 25-59 years; 31 men and 15 women), and 16 healthy controls (age 26-61 years; 11 men and 5 women) were enrolled in a validation group. Enzyme-linked immunosorbent assay was used to verify the diagnostic value of the candidate biomarkers. We found 139 proteins that were differentially expressed between various fibrotic stage-paired comparisons. Five protein candidates were selected as potential biomarkers of S2 for further verification. Notably, ficolin-2 (FCN2) and carboxypeptidase B2 (CPB2) showed differential expression between patients and healthy controls. In conclusion, serum proteomic changes reported here offer new molecular leads for future research on biomarker candidates to identify liver fibrotic stages in CHB. In particular, FCN2 and CPB2 warrant further research on their possible mechanistic involvement in CHB pathogenesis.


Subject(s)
Biomarkers/blood , Hepatitis B, Chronic/blood , Liver Cirrhosis/blood , Proteomics/methods , Adult , Carboxypeptidase B2/blood , Enzyme-Linked Immunosorbent Assay , Female , Humans , Lectins/blood , Male , Middle Aged , Severity of Illness Index , Ficolins
11.
Medicine (Baltimore) ; 97(36): e12279, 2018 Sep.
Article in English | MEDLINE | ID: mdl-30200171

ABSTRACT

We aimed to analyze factors related to human immunodeficiency virus (HIV) infection among 15 to 25-year-old rural unmarried Yi adolescents in Liangshan Yi Autonomous Prefecture from 2011 to 2016, and to investigate the relationship among the HIV-related risk factors.Three sites (Butuo, Zhaojue, and Ganluo counties) with a Yi population were selected from 2011 to 2016 in Liangshan prefecture. We used questionnaires to investigate demographic and behavioral characteristics and performed HIV testing. Logistic regression analysis and multiple correspondence analysis (MCA) were used to analyze the data.A total of 6311 qualified rural unmarried Yi adolescents were involved in this study, with an HIV infection rate of 4.18% (264/6311). Logistic regression analysis indicated that males (OR = 1.56, 95% CI = 1.17-2.08), illiteracy (OR = 2.70, 95% CI = 1.79-4.08), primary school education or below (OR = 1.62, 95% CI = 1.12-2.36), history of out-migrating for work (OR = 1.58, 95% CI = 1.18-2.13), and injecting drug user (IDU) (OR = 6.42, 95% CI = 3.06-13.46) contributed to the risk of HIV infection. MCA revealed a strong interrelationship between the following risk factors and HIV infection: aged 23 to 25 years, IDU, history of out-migrating for work, and ever having sexual behaviors.HIV infection among 15 to 25-year-old rural unmarried Yi adolescents in Liangshan is a serious issue. MCA and logistic regression analysis can be used to assess the relationship between risk factors for HIV infection.


Subject(s)
HIV Infections/epidemiology , Adolescent , Adult , China/epidemiology , Educational Status , Female , Humans , Logistic Models , Male , Multivariate Analysis , Risk Factors , Rural Population , Sex Factors , Single Person , Surveys and Questionnaires , Transients and Migrants , Young Adult
12.
Medicine (Baltimore) ; 97(14): e0250, 2018 Apr.
Article in English | MEDLINE | ID: mdl-29620638

ABSTRACT

We aimed to evaluate HIV prevalence among residents of Liangshan Prefecture through HIV sentinel surveillance (HSS) data over the period from 2010 to 2016, and investigate risk factors for HIV infection in this population and interactions among them.Two sites (Dechang and Ningnan counties) with majority-Han populations, and 1 site (Butuo) with a majority-Yi population were selected. We used questionnaires to investigate residents' demographic and behavioral characteristics from 2010 to 2016, and performed HIV testing. Multivariate logistic regression and path analysis were undertaken to investigate the interactions and mediating effects among significant risk factors for HIV infection.A total of 5403 community residents in the Yi area and 10,897 community residents in the Han areas were enrolled. HIV prevalence in the Yi area was consistently high, ranging from 9.46% (63/666, 2011) to 2.88% (23/798, 2012) over the period from 2010 to 2016. HIV prevalence in the Han areas ranged from 0.15% (2/1333, 2010) to 0.44% (7/1604, 2011) over the same period. Multivariate logistic regression showed that unprotected casual sexual behavior, male gender, illiteracy, drug use, and injection drug use were positively associated with HIV infection risk in the Yi area. Path analysis of the risk factors revealed that casual sexual behavior (0.051) and injection drug use (0.161) were directly associated with HIV infection. However, marital status (0.004), ethnicity (0.017), education level (-0.004), HIV/AIDS-related prevention knowledge (-0.012), and drug use (0.11) had an indirect influence on HIV infection through casual sexual behavior and injection drug use.The prevalence of HIV is high among residents of majority-Yi areas, and injection drug use and casual sexual behavior are risk factors for infection.


Subject(s)
Ethnicity/statistics & numerical data , HIV Infections/etiology , Minority Groups/statistics & numerical data , Sentinel Surveillance , Adult , China/epidemiology , China/ethnology , Female , HIV Infections/epidemiology , HIV Infections/ethnology , Humans , Male , Mass Screening , Risk Factors , Sexual Behavior/ethnology , Substance Abuse, Intravenous/epidemiology , Substance Abuse, Intravenous/ethnology , Substance Abuse, Intravenous/virology , Surveys and Questionnaires
13.
AIDS Care ; 30(8): 1058-1061, 2018 08.
Article in English | MEDLINE | ID: mdl-29499120

ABSTRACT

We evaluated HIV prevalence among unmarried youth in rural areas of Liangshan Prefecture in southwest China over the period of 2011-2015, and the interactions between behaviors associated with HIV risk. We used HIV sentinel surveillance (HSS) data for our analysis. We used questionnaires to investigate information among unmarried youth aged 15 to 25 years and performed HIV testing. Multivariate logistic regression and path analysis were applied to explore associations between behavioral factors related with HIV infection. A total of 9536 unmarried youth were enrolled in this study, of whom 2.75% (262/9536) tested positive for HIV infection. Multivariate logistic regression showed that male gender, Yi ethnicity, illiteracy, out-migrating for work, needle sharing, and engaging in high-risk sexual behaviors were risk factors. Path analysis revealed that needle sharing had the greatest effect on HIV infection (0.267), followed by drug use (0.171), out-migrating for work (0.079), and high-risk sexual behavior (0.064). The epidemic of HIV infection among unmarried youth in rural areas of Liangshan Prefecture is severe, and prevention efforts should focus on high-risk groups such as youth who are male, Yi, illiterate, and out-migrating for work, and those who engage in high-risk sexual behaviors and needle sharing.


Subject(s)
HIV Infections/epidemiology , Needle Sharing , Sexual Behavior , Adolescent , Adult , China/epidemiology , Female , Humans , Logistic Models , Male , Mass Screening , Prevalence , Risk Factors , Sentinel Surveillance , Single Person , Surveys and Questionnaires , Young Adult
14.
PLoS One ; 12(9): e0183418, 2017.
Article in English | MEDLINE | ID: mdl-28880917

ABSTRACT

BACKGROUND: Yi people make up about 50% of the population in Liangshan Prefecture, Sichuan Province, China, but accounted for 88.07% of new HIV cases in the prefecture from 2011 to 2013. This study evaluated HIV prevalence in pregnant women of Liangshan Prefecture using HIV sentinel surveillance (HSS) data over the period of 2009 to 2015. METHODS: Xichang, Zhaojue County, and Butuo County were selected as HSS sites. We investigated the temporal trends in HIV prevalence in these areas, and the association between demographic and behavioral characteristics and risk of HIV infection. RESULTS: Data on a total of 2797 pregnant women in Xichang and 3983 pregnant women in Zhaojue and Butuo was collected for the period 2009 to 2015. There was a fluctuating HIV prevalence among pregnant women of Xichang, with a rate of 0.75% in 2015 (χ2trend = 2.27, P = 0.13). HIV prevalence among pregnant women of Zhaojue and Butuo was consistently high, varying between 3.4% (9/267, 2011) and 10.3% (82/796, 2012) over the period of 2010 to 2015 (χ2trend = 0.12, P = 0.73). In Xichang, we found that Yi ethnicity (OR = 11.37, 95% CI = 2.92-44.25) and a husband who used drugs (OR = 32.13, 95% CI = 5.33-193.67) were significantly associated with HIV risk in pregnant women. For Zhaojue and Butuo, we observed that pregnant women had a higher risk of HIV infection when they were over 30 years old (OR = 1.72, 95% CI = 1.17-2.52), when they had a higher number of previous births, when their husbands had a history of migrating for work (OR = 1.56, 95% CI = 1.16-2.08), and when they had a history of other sexually transmitted infections (OR = 2.19, 95% CI = 1.16-2.08). Compared to those with a primary school education or below, pregnant women with a secondary or high school education level had a lower risk of HIV infection (OR = 0.28, 95% CI = 0.09-0.89). CONCLUSION: Our results indicate that there is a serious HIV epidemic among pregnant Yi women, especially for those with less education, more past births, or a husband with a history of out-migrating for work or STD infection.


Subject(s)
HIV Infections/epidemiology , Adult , China/epidemiology , Female , Humans , Logistic Models , Multivariate Analysis , Pregnancy , Prevalence , Surveys and Questionnaires
15.
Medicine (Baltimore) ; 95(27): e3969, 2016 Jul.
Article in English | MEDLINE | ID: mdl-27399071

ABSTRACT

Human immunodeficiency virus (HIV)-positive cases have been reported among people who injected drugs in Liangshan Prefecture in southwest of China since 1995 and Liangshan has become one of the most seriously affected epidemic areas in China. In 2004, several patients with HIV/acquired immunodeficiency syndrome (AIDS) initiated antiretroviral treatment (ART) at the Central Hospital of Liangshan Prefecture. From 2005 to 2013, the number of patients receiving ART dramatically increased.We conducted a retrospective cohort study to analyze the long-term survival time and associated factors among patients with HIV/AIDS who received ART in Liangshan Prefecture for the first time. Data were collected from the Chinese AIDS Antiretroviral Therapy DATAFax Information System. A life table and the Kaplan-Meier and Cox proportion hazard regression were used to calculate the survival time and its associated factors, respectively.Among 8310 ART-naïve patients with HIV/AIDS who initiated ART, 436 patients died of AIDS-related diseases, and their median time of receiving ART was 15.0 ±â€Š12.3 months, whereas 28.7% of them died within the first 6 months after treatment. The cumulative survival rates of those receiving ART in 1, 2, 3, 4, and 5 years were 97.1%, 93.4%, 90.6%, 88.8%, and 86.0%, respectively. Multivariate Cox regression analysis showed that male patients on ART were at a higher risk of death from AIDS-related diseases (adjusted hazard ratio [AHR] = 1.5, 95% confidence interval [CI]: 1.1-2.1) than female patients. Patients infected with HIV through injection drug use (IDU) were at a higher risk of death (AHR = 1.6, 95% CI: 1.2-2.2) than those infected through heterosexual transmission. Patients with a baseline CD4 cell count <50/mm (AHR = 9.8, 95% CI: 6.0-15.9), 50-199/mm (AHR = 3.3, 95% CI: 2.3-4.6), and 200-349/mm (AHR = 1.7, 95% CI: 1.2-2.3) were at a higher risk of death than those with a CD4 cell count ≥350/mm.ART prolonged survival time of patients with HIV/AIDS and improved their survival probability. Patients with HIV/AIDS should be consistently followed up and the CD4 T-cell count regularly monitored, and timely and early antiretroviral therapy initiated in order to achieve a better survival rate.


Subject(s)
Acquired Immunodeficiency Syndrome/drug therapy , Acquired Immunodeficiency Syndrome/mortality , Anti-Retroviral Agents/therapeutic use , Adult , China/epidemiology , Cohort Studies , Female , HIV Infections/drug therapy , HIV Infections/mortality , Humans , Male , Middle Aged , Retrospective Studies , Survival Rate , Time Factors , Treatment Outcome , Young Adult
16.
Infect Dis Model ; 1(1): 3-10, 2016 Oct.
Article in English | MEDLINE | ID: mdl-29928717

ABSTRACT

BACKGROUND: As a response to a severe HIV epidemic in the Liangshan Prefecture, one of the worst in China, population based HIV interventions, including two population-wide HIV screening, have been carried out since 2005 at two townships in a remote mountainous region of Liangshan. The objective of our mathematical modeling study is to assess the temporal dynamics of the HIV epidemic in the two townships based on the data collected in the study area during the period 2005-2010. METHODS: A mathematical model was set up to describe the population dynamics of HIV transmission in study area. The model was calibrated by fitting it to the HIV testing and treatment data from 2005 to 2008. Validation of the model was done by comparing its predicted value of HIV prevalence in 2010 to the prevalence data obtained in the 2010 population wide HIV testing. The validated model was used to produce estimation of HIV incidence, prevalence and death. RESULTS: Our model estimations show that population-based HIV interventions have significantly slowed down the rise of the HIV epidemic in the two townships. Over the five-year period from 2005 to 2010, the year-over-year rate of increase in HIV incidence, prevalence, and death has declined by 91.5%, 28.7%, and 52.3%, respectively. CONCLUSION: Mathematical models, when integrated with epidemiological and surveillance data, can be an effective tool for predicting the temporal dynamics of HIV and assessing the impacts of HIV interventions.

17.
Zhonghua Liu Xing Bing Xue Za Zhi ; 36(6): 569-75, 2015 Jun.
Article in Chinese | MEDLINE | ID: mdl-26564626

ABSTRACT

OBJECTIVE: To investigate the survival time and affecting factors among AIDS patients under antiretroviral treatment, between 2008 and 2013 in Liangshan, Sichuan province. METHODS: Observational retrospective cohort study method was applied. AIDS patients were chosen from China's national comprehensive prevention and control management system of AIDS in Liangshan, during 2008-2013. Related information on demographics, source of infection, pathogenesis, treatment and death was collected. Cox proportional hazards model was applied to analyze the factors that might affect the survival on patients. RESULTS: Among the 8 321 cases, ranging from 18 to 87.5 years old (mean age as 34.2 ± 9.8), 3 021 died and 3 721 patients had received HAART treatment. The total mortality rate dropped from 43.9/100 person-years to 20.7/100 person-years from 2008 to 2013. In the treatment group, mortality rate dropped from 27.3/100 person-years to 5.1/100 person-years, while in the untreated group it remained high-between 45.0/100-50.8/100 person-years. Proportion for the treatment coverage increased gradually, from 5.8% in 2008 to 54.5% in 2013. Median survival time of all the AIDS patients was 35.1 months, but 18.4 months in the untreated group. Survival of all the AIDS patients was associated with factors as: treatment, age when AIDS diagnosis was made and route of HIV infection (P < 0.05). The risk of death among untreated patients was 5.78 times to the treated ones, but did not seem to relate to gender or nationality (P > 0.05). Survival of the treated group was associated with factors as gender, age when AIDS diagnosis was made, nationality, route of HIV infection, CD4(+) T cell count when AIDS diagnosis was made, CD4(+) T cell count at treatment baseline, anemia at the treatment baseline (P < 0.05). Survival of the untreated group was mainly associated with age when AIDS was diagnosed (P < 0.05) while other factors did not seem to be significantly related (P > 0.05). CONCLUSION: Antiretroviral therapy appeared an important factor that affecting the survival of AIDS patients, timely treatment and CD4(+) T cell count provided at the baseline for treatment, were two key factors that affecting the outcome of treatment. Our findings pointed out that tactic factors as: strengthening the detection, monitoring on CD4(+) T cell count, early diagnose and treatment, expanding the coverage of antiretroviral therapy, and appropriate timing for treatment etc., were important ways to enhance the effects of treatment, so as to reduce the mortality rate and prolong the time of survival.


Subject(s)
Acquired Immunodeficiency Syndrome/drug therapy , Acquired Immunodeficiency Syndrome/mortality , Antiretroviral Therapy, Highly Active , Adolescent , Adult , Aged , Aged, 80 and over , CD4 Lymphocyte Count , China/epidemiology , Female , Humans , Male , Middle Aged , Proportional Hazards Models , Retrospective Studies , Survival Rate , Time-to-Treatment , Treatment Outcome , Young Adult
18.
Infect Dis Poverty ; 4: 38, 2015 Sep 02.
Article in English | MEDLINE | ID: mdl-26329887

ABSTRACT

BACKGROUND: Previous studies have shown inconsistent or even contradictory results for some risk factors associated with HIV infection among drug users, and these may be partially explained by geographical variations. METHODS: Data were collected from 11 methadone clinics in the Liangshan Yi Autonomous Prefecture from 2004 to 2012. A non-spatial logistical regression model and a geographically weighted logistic regression model were fitted to analyze the association between HIV infection and specific factors at the individual level. RESULTS: This study enrolled 6,458 patients. The prevalence of HIV infection was 25.1 %. The non-spatial model indicated that being divorced was positively associated with HIV infection. The spatial model also showed that being divorced was positively associated with HIV infection, but only for 49.4 % of individuals residing in some northern counties. The non-spatial model suggested that service sector work was negatively associated with HIV infection. However, the spatial model indicated that service work was associated with HIV infection, but only for 23.0 % of patients living in some western counties. The non-spatial model did not show that being married was associated with HIV infection in our study field, but the spatial model indicated that being married was negatively associated with HIV infection for 12.0 % of individuals living in some western counties. For other factors, the non-spatial and spatial models showed similar results. CONCLUSION: The spatial model may be useful for improving understanding of geographical heterogeneity in the relationship between HIV infection and individual factors. Spatial heterogeneity may be useful for tailoring intervention strategies for local regions, which can consequently result in a more efficient allocation of limited resources toward the control of HIV transmission.


Subject(s)
Drug Users , HIV Infections/epidemiology , China/epidemiology , Female , Geography, Medical , HIV Infections/transmission , Humans , Male , Models, Statistical , Prevalence , Risk Factors
19.
Zhonghua Yu Fang Yi Xue Za Zhi ; 49(11): 967-72, 2015 Nov.
Article in Chinese | MEDLINE | ID: mdl-26833006

ABSTRACT

OBJECTIVE: To investigate the survival time and its impact factors among AIDS patients who initially received antiretroviral treatment (ART) of Liangshan Yi Autonomous Prefecture, Sichuan province. METHODS: A retrospective cohort study was conducted to analyze the information of AIDS patients over 18 years old initially received ART in Liangshan Yi Autonomous Prefecture during 2005-2013, which were downloaded from Chinese AIDS Antiretroviral Therapy DATA Fax Information System. Cox proportion hazard regression model was used to identify impact factors related survival time. RESULTS: Among 8 310 ART AIDS patients who initially received ART, their mean age was (34.59 ± 9.10) years old, 65.50% (5 443 cases) were infected with HIV through injecting drug use, the mean time from testing HIV positive to starting ART were (24.68 ± 21.69) months. 436 cases died of AIDS related diseases, 28.67% (125 cases) of them died within the first 6 months of treatment. The cumulative survival rate of receiving ART in 1, 2, 3, 4 5 years were 97.11%, 93.41%, 90.61%, 88.81%, 86.02%, respectively. Multivariate Cox regression analysis showed the male patients receiveing ART were at a higher risk death of AIDS related diseases compared to the females (HR = 1.57, 95% CI: 1.13-2.182), the patients infected with HIV through injecting drug use were at a higher risk deathcompared to the infected through heterosexual transmission (HR = 1.64, 95% CI: 1.20-2.24), before the treatment patients with tuberculosis in recent1 year had higher death hazard as compared to those without tuberculosis (HR = 1.53, 95% CI: 1.05-2.21), in the treatment of the first 3 months of AIDS related diseases or symptoms of AIDS patients had higher death hazard as compared to those not suffer these diseases (HR = 1.80, 95% CI: 1.39-2.34). The patients with baseline CD4 (+) T lymphocytes cell counts < 50/µl (HR = 9.79, 95% CI: 6.03-15.89), 50-199/µl (HR = 3.26, 95% CI: 2.32-4.59), 200-349/µl (HR = 1.69, 95% CI: 1.22-2.34), were at a higher risk death than those with CD4 (+) T lymphocytes cell counts ≥ 350/µl. CONCLUSION: Accumulate survival rate was higher after initial antiretroviral treatment among AIDS patients in Liangshan Yi Autonomous Prefecture, Sichuan province. AIDS patients who are males, have tuberculosis in recent year, infected HIV via route of intravenous drug use, with AIDS-related illness or symptoms in 3 months before ART, lower baseline CD4 (+) T lymphocyte count have higher risk of death.


Subject(s)
Acquired Immunodeficiency Syndrome/mortality , Anti-Retroviral Agents/therapeutic use , Acquired Immunodeficiency Syndrome/drug therapy , Adult , Asian People , China , Female , Humans , Lymphocyte Count , Male , Proportional Hazards Models , Retrospective Studies , Risk Factors , Substance Abuse, Intravenous , Survival Rate , Tuberculosis/complications
20.
Zhonghua Yu Fang Yi Xue Za Zhi ; 48(8): 678-83, 2014 Aug.
Article in Chinese | MEDLINE | ID: mdl-25388462

ABSTRACT

OBJECTIVE: To analyze the survival time and its related factors among AIDS patients in Liangshan prefecture of Sichuan province from 1995 to 2012. METHODS: A retrospective cohort study was conducted to analyze the information of 5 263 AIDS patients. The data were collected from Chinese HIV/AIDS Comprehensive Information Management System. Life table method was applied to calculate the survival proportion, and Kaplan-Meier and Cox proportion hazard regression model were used to identify the factors related to survival time. RESULTS: Among 5 273 AIDS patients, 819 (15.6%)died of AIDS related diseases; 2 782(52.9%) received antiretroviral therapy. The average survival time was 126.7 (117.1-136.2) months, and the survival rate in 1, 5, 10, 15 years were 95.4%, 78.8%, 54.2%, and 31.8% respectively. Univariate analysis showed a significant difference in survival time of age diagnosed as AIDS patients, nationality, transmission route, AIDS phase, CD4(+)T cell counts in the last testing, receiving antiretroviral therapy or not. Multivariate Cox regression showed age diagnosed AIDS below 50 years old ( < 15 years old:HR = 0.141, 95%CI:0.036-0.551;15-49 years old:HR = 0.343, 95%CI:0.241-0.489), HIV infection diagnosed phase (HR = 0.554, 95%CI:0.432-0.709), CD4(+)T cell counts last testing ≥ 350/µl (HR = 0.347, 95%CI:0.274-0.439) reduced the risk of dying of AIDS related diseases among AIDS patients. The patients having not received antiretroviral therapy had a higher risk of death(HR = 3.478, 95%CI:2.943-4.112) compared to those who received antiretroviral therapy. CONCLUSION: Survival time of AIDS patients was possibly mainly influenced by the age of diagnosed as AIDS patients, AIDS phase, CD4(+)T cell counts and whether or not received antiretroviral therapy. The early initiation of antiretroviral therapy could extend the survival time.


Subject(s)
Acquired Immunodeficiency Syndrome/mortality , China/epidemiology , Cohort Studies , HIV Infections , Humans , Proportional Hazards Models , Retrospective Studies , Survival Analysis , Survival Rate
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