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1.
BMC Plant Biol ; 24(1): 224, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38539093

RESUMO

BACKGROUND: Drought severely limits sunflower production especially at the seedling stage. To investigate the response mechanism of sunflowers to drought stress, we utilized two genotypes of sunflower materials with different drought resistances as test materials. The physiological responses were investigated under well-watered (0 h) and drought-stressed conditions (24 h, 48 h, and 72 h). RESULTS: ANOVA revealed the greatest differences in physiological indices between 72 h of drought stress and 0 h of drought stress. Transcriptome analysis was performed after 72 h of drought stress. At 0 h, there were 7482 and 5627 differentially expressed genes (DEGs) in the leaves of K55 and K58, respectively, and 2150 and 2527 DEGs in the roots of K55 and K58, respectively. A total of 870 transcription factors (TFs) were identified among theDEGs, among which the high-abundance TF families included AP2/ERF, MYB, bHLH,and WRKY. Five modules were screened using weighted gene coexpressionnetwork analysis (WGCNA), three and two of which were positively and negatively, respectively, related to physiological traits. KEGG analysis revealedthat under drought stress, "photosynthesis", "carotenoid biosynthesis", "starch and sucrose metabolism", "ribosome", "carotenoid biosynthesis", "starch and sucrose metabolism", "protein phosphorylation" and "phytohormone signaling" are six important metabolic pathways involved in the response of sunflower to drought stress. Cytoscape software was used to visualize the three key modules, and the hub genes were screened. Finally, a total of 99 important candidate genes that may be associated with the drought response in sunflower plants were obtained, and the homology of these genes was compared with that in Arabidopsis thaliana. CONCLUSIONS: Taken together, our findings could lead to a better understanding of drought tolerance in sunflowers and facilitate the selection of drought-tolerant sunflower varieties.


Assuntos
Arabidopsis , Helianthus , Humanos , Transcriptoma , Helianthus/genética , Helianthus/metabolismo , Resistência à Seca , Perfilação da Expressão Gênica , Secas , Arabidopsis/genética , Amido/metabolismo , Carotenoides/metabolismo , Sacarose/metabolismo , Estresse Fisiológico/genética , Regulação da Expressão Gênica de Plantas
2.
Inorg Chem ; 63(11): 5076-5082, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38447153

RESUMO

Herein, two Laves intermetallic series, ZrCo1.75M0.25 and NbCo1.75M0.25 (M = Fe, Co, Ni, Ru, Rh, Pd, Os, Ir, and Pt), were synthesized, and their hydrogen evolution reaction (HER) activities were examined to reveal the influence of d electrons to the corresponding HER activities. Owing to the different electronegativity between Zr and Nb (χZr = 1.33; χNb = 1.60), Co and/or M elements receive more electrons in ZrCo1.75M0.25 than that of the Nb one. This leads to the overall weak H adsorption energy (ΔGHad) of ZrCo1.75M0.25 series compared to that of NbCo1.75M0.25 and rationalizes well the superior HER activity of the Rh member compared to that of the Pt one in the ZrCo1.75M0.25 series. Under industrial conditions (333 K, 6.0 M KOH), ZrCo1.75Rh0.25 only requires an overpotential of 110 mV to reach the current density of 500 mA/cm2 and can be operated at high current density over 400 h. This work demonstrates that with a proper combination between elements in intermetallic phases, one can manipulate d electrons of the active metal to be closer to the sweet spot (ΔGHad = 0). The Pt member may no longer exhibit the best HER activity in series, and all elements exhibit the potential to outperform the Pt member in the HER with careful control of the d electron population.

3.
Molecules ; 29(9)2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38731571

RESUMO

The dyes in printing and dyeing wastewater are harmful to the human body and the environment. It is essential to develop practical and effective adsorbents to deal with them. In this study, an Fe-doped, ZIF-67 derived Fe/Co/C composite material with strong magnetism was successfully synthesized. The effects of pH, initial concentration, and adsorption time on the properties of the adsorbent were investigated. To further improve the removal efficiency and enhance the practicality, potassium peroxymonosulfate (PMS) was added to the system due to its Fenton-like effect. Then, an Fe/Co/C composite was used with PMS to remove Congo red (CR) with a 98% removal of 250 mg·L-1. Moreover, for its high saturation magnetization of 85.4 emu·g-1, the Fe/Co/C composite can be easily recovered by applying a magnetic field, solving the problem that powdery functional materials are difficult to recover and, thus, avoiding secondary pollution. Furthermore, since the composite material was doped before carbonization, this synthetic strategy is flexible and the required metal elements can be added at will to achieve different purposes. This study demonstrates that this Fe-doped, ZIF-67 derived magnetic material has potential application prospects for dye adsorption.

4.
J Environ Sci (China) ; 138: 418-427, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38135407

RESUMO

Bi2O2CO3(BOC)/Bi4O5Br2(BOB)/reduced graphene oxide (rGO) Z-scheme heterojunction with promising photocatalytic properties was synthesized via a facile one-pot room-temperature method. Ultra-thin nanosheets of BOC and BOB were grown in situ on rGO. The formed 2D/2D direct Z-scheme heterojunction of BOC/BOB with oxygen vacancies (OVs) effectively leads to lower negative electron reduction potential of BOB as well as higher positive hole oxidation potential of BOC, showing improved reduction/oxidation ability. Particularly, rGO is an acceptor of the electrons from the conduction band of BOC. Its dual roles significantly improve the transfer performance of photo-induced charge carriers and accelerate their separation. With layered nanosheet structure, rich OVs, high specific surface area, and increased utilization efficiency of visible light, the multiple synergistic effects of BOC/BOB/rGO can achieve effective generation and separation of the electron-holes, thereby generating more •O2- and h+. The photocatalytic reduction efficiency of CO2 to CO (12.91 µmol/(g·hr)) is three times higher than that of BOC (4.18 µmol/(g·hr)). Moreover, it also achieved almost 100% removal of Rhodamine B and cyanobacterial cells within 2 hours.


Assuntos
Elétrons , Grafite , Temperatura , Oxigênio
5.
Small ; 19(32): e2208211, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37078912

RESUMO

Nowadays, the exploration of electromagnetic (EM) wave absorbers with anticorrosion to improve the survivability and environmental adaptability of military targets in the harsh environments is becoming an attractive and unavoidable challenge. Herein, through modulation of the metal composition in the precursors, the core@shell structure Prussian blue analog-derived NiCo@C, CoFe@C, NiFe@C, and NiCoFe@C are obtained with excellent EM wave absorption performance. As for NiCoFe@C, ascribed to the coupling effect of the dual magnetic alloy, a minimum reflection loss (RL) of -47.6 dB and an effective absorption bandwidthof 5.83 GHz are realized, which cover the whole Ku-band. Meanwhile, four absorbers display the lower corrosion current density (10-4 -10-6 A cm-2 ) and larger polarization resistance (104 -106  Ω) under acid, neutral, and alkaline corrosion conditions over uninterrupted 30 days. Furthermore, due to the spatial barrier effect and the passivation effect of the graphitic carbon shell , the continuous salt spray test has little effect on RL performance and inconspicuously changes the surface morphologies of coating, demonstrating its excellent bifunctional performance. This work lays the foundation for the development of metal-organic frameworks-derived materials with both anticorrosion and EM wave absorption performance.

6.
Small ; 19(28): e2301075, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36978240

RESUMO

Defect chemistry in carbon matrix shows great potential for promoting the oxygen reduction reaction (ORR) of metal single-atom catalysts. Herein, a modified pyrolysis strategy is proposed to tune carbon defects in copper single-atom catalysts (Cu-SACs) to fully understand their positive effect on the ORR activity. The optimized Cu-SACs with controllable carbon defect degree and enhanced active specific surface area can exhibit improved ORR activity with a half-wave potential of 0.897 VRHE , ultrahigh limiting current density of 6.5 mA cm-2 , and superior turnover frequency of 2.23 e site-1 s-1 . The assembled Zn-air batteries based on Cu-SACs can also show well-retained reversibility and voltage platform over 1100 h charge/discharge period. Density functional theory calculations reveal that suitable carbon defects can redistribute charge density of Cu-N4 active sites to weaken the O-O bond in adsorbed OOH* intermediate and thus reduce its dissociation energy. This discovery offers a universal strategy for fabricating superior single-atom catalysts with high-efficiency active sites toward energy-directed applications.

7.
Ann Behav Med ; 57(11): 978-987, 2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37435876

RESUMO

BACKGROUND: Since HIV has evolved into a lifelong but manageable condition, improving the quality of life (QoL) of persons living with HIV (PLWHs) has become increasingly important. Living with HIV is life-altering and poses substantial challenges for both PLWHs and their partners, so identifying how HIV serodiscordant couples cope with HIV together is crucial. Here, Bodenmann's Systemic Transaction Model highlights common dyadic coping (CDC), which refers to both partners working together to alleviate the negative effects of stress. PURPOSE: We examined the mediating role of CDC in linking we-disease appraisal with relationship satisfaction and QoL. METHODS: We recruited a convenience sample of 231 HIV serodiscordant couples via local grassroots organizations between June and October 2022. Participants completed measures of we-disease appraisal, CDC, relationship satisfaction, and QoL. We examined the mediation effect of CDC on the association between we-disease appraisal and outcomes using the common fate mediation model. RESULTS: The mean age of PLWHs was 32.18 years (standard deviation = 8.61 years), and that of their partners was 32.55 years (standard deviation = 9.24 years). The average time since HIV diagnosis was 4.18 years. Most couples were same-sex male couples. We found that CDC mediated the effect of we-disease appraisal on relationship satisfaction. Moreover, CDC significantly mediated the effect of we-disease appraisal on the QoL of PLWHs and their partners. CONCLUSIONS: Our findings highlight the importance of CDC in dyadic illness management among Chinese HIV serodiscordant couples.


Numerous studies have shown that HIV serodiscordant couples may face HIV-related stress as a unit. Yet, it is not clear how the appraisal of HIV as a shared illness (i.e., we-disease appraisal) may influence relationship satisfaction and both partners' quality of life (QoL) via common dyadic coping (CDC) behaviors (e.g., collaboration). In this study, we collected data from 231 HIV serodiscordant couples. Participants completed reports of how they appraise HIV as a we-disease, their CDC behaviors, and their relationship satisfaction and QoL. We found that we-disease appraisal was positively associated with CDC, which in turn was positively associated with relationship satisfaction and both partners' QoL. Future couple-based interventions should incorporate psycho-educational components to raise awareness about we-disease appraisal, as well as skill-building components to encourage the use of CDC in clinical settings.

8.
AIDS Behav ; 27(1): 314-334, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35838860

RESUMO

This systematic review and meta-analysis aims to compare the effects of couple-based prevention interventions against individual-level interventions on HIV prevention in randomized controlled trials (RCTs), identify potential moderators, and assess study quality. Eleven RCTs were included, comprising 3933 couples in the intervention group and 7125 individuals in the individual control group, predominantly in heterosexual couples from the USA and Africa. Couple-based interventions had a more significant effect in promoting condom use and HIV testing. Education levels of high school or above, residence in low- and middle-income countries, and intervention design incorporating HIV counseling and testing were associated with higher odds of condom use. The quality assessment analysis identified methodological and theoretical heterogeneity factors. Evidence of couple-based HIV prevention RCTs among men who have sex with men, injecting drug users, sex workers, and transgender women warrant further investigation. Recommendations are made to improve the quality and replicability of future intervention studies.


RESUMEN: Esta revista sistemática y metanálisis tiene por objeto comparar los efectos de las intervenciones de prevención basadas en pareja con las a nivel individual en la prevención del VIH en ensayos controlados aleatorios (ECA), identificar posibles moderadores y evaluar la calidad de los estudios. Se incluyeron once ECA, que comprendían 3.933 parejas en el grupo de intervención y 7.125 personas en el grupo de control individual, la mayoría de las cuales eran heterosexuales de EE.UU. y de África. Las intervenciones basadas en pareja son más eficaces para promover el uso de preservativos y pruebas del VIH. Los niveles de educación secundaria o superior, los países de ingresos bajos y medianos, y los diseños de intervención que incluyen pruebas y asesoramiento sobre el VIH se relacionan con más uso de preservativos. El análisis de evaluación de la calidad ha identificado factores de heterogeneidad metodológica y teórica. Las pruebas de ECA basadas en pareja para la prevención del VIH en hombres que tienen sexo con hombres, consumidores de drogas inyectables, trabajadoras sexuales y mujeres transgénero necesitan más investigación. Se hacen recomendaciones para mejorar la calidad y replicabilidad de futuros estudios de intervención.


Assuntos
Síndrome da Imunodeficiência Adquirida , Infecções por HIV , Masculino , Feminino , Humanos , Infecções por HIV/prevenção & controle , Ensaios Clínicos Controlados Aleatórios como Assunto , Sexo Seguro , Aconselhamento , Heterossexualidade
9.
AIDS Behav ; 27(3): 823-831, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36044125

RESUMO

With the recent endorsement of PrEP by the Chinese government, research is urgently needed to better understand factors impacting PrEP uptake among gay, bisexual, and other men who have sex with men (GBMSM) in China. This study examined willingness to use PrEP for HIV prevention among GBMSM in China through structural equation modeling. We examined the relationship among PrEP-related attitudes, subjective norms, PrEP-related knowledge and beliefs about medicines and willingness to use PrEP. The analysis showed a good fit between the data and both the measurement model (RMSEA = 0.060) and structural model (RMSEA = 0.054). Knowledge, attitudes, and subjective norms were significantly related to intention to use PrEP, whereas the effect of general beliefs about medicines was insignificant. These effect mechanisms point to the importance of designing interventions to support PrEP uptake that target knowledge, enhance positive attitudes about PrEP within social networks, and build positive social norms around PrEP among sexually active GBMSM.


Assuntos
Infecções por HIV , Profilaxia Pré-Exposição , Minorias Sexuais e de Gênero , Masculino , Humanos , Homossexualidade Masculina , Análise de Classes Latentes , Infecções por HIV/prevenção & controle , China
10.
Phys Chem Chem Phys ; 25(42): 29182-29191, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37870596

RESUMO

In recent years, two-dimensional materials have aroused enormous interest owing to their superior electrochemical performance, abundant exposed active sites, high specific surfaces and so on. Unlike many stable allotropes, honeycomb hexagonal borophene is kinetically unstable. In this study, we introduce transition metal atoms (Cr, Fe and Co) to stabilize honeycomb hexagonal borophene, forming stable graphene-like TMB6 (TM = Cr, Fe and Co) monolayers. Moreover, we explored the possibility of superconductivity and the anchoring materials of lithium-sulfur batteries using the first-principles density functional theory (DFT) calculation. Our results show that CoB6 exhibited the best superconductivity with a superconducting transition temperature of 33.3 K. Furthermore, CoB6 and FeB6 are promising anchoring materials because of the suppression of lithium polysulfides shuttling in lithium-sulfur batteries because they can accelerate sulfur reduction reaction kinetics.

11.
Phys Chem Chem Phys ; 24(24): 14953-14963, 2022 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-35686533

RESUMO

In the recent past, beryllium-boron compounds have been the focus of attention as a consequence of their extremely rich structures and potential applications. Nevertheless, their complex phase structures greatly hinder further exploration of the physical and chemical properties. To this end, we propose a novel beryllium-boron compound based on a two-dimensional (2D) structure, namely a Be2B2 monolayer. Using first-principles methods, we first prove that the structure of the 2D Be2B2 monolayer is energetically and thermodynamically stable. Subsequently, we systematically explored its potential as a high performance anode material for LIBs and NIBs. The results reveal that the Be2B2 monolayer exhibits an excellent, comprehensive performance with a strong adsorption energy, low diffusion barrier, suitable average open circuit voltage and outstanding electronic conductivity. More importantly, the extremely high theoretical specific capacity (1352 mA h g-1 for both LIBs and NIBs) well meets our expectations, which is quite ideal for an anode material. Meanwhile, we hope and believe that this work can provide some new insights into the study of beryllium-boron compounds.

12.
Molecules ; 27(7)2022 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-35408467

RESUMO

Photocatalytic CO2 reduction is a most promising technique to capture CO2 and reduce it to non-fossil fuel and other valuable compounds. Today, we are facing serious environmental issues due to the usage of excessive amounts of non-renewable energy resources. In this aspect, photocatalytic CO2 reduction will provide us with energy-enriched compounds and help to keep our environment clean and healthy. For this purpose, various photocatalysts have been designed to obtain selective products and improve efficiency of the system. Semiconductor materials have received great attention and have showed good performances for CO2 reduction. Titanium dioxide has been widely explored as a photocatalyst for CO2 reduction among the semiconductors due to its suitable electronic/optical properties, availability at low cost, thermal stability, low toxicity, and high photoactivity. Inspired by natural photosynthesis, the artificial Z-scheme of photocatalyst is constructed to provide an easy method to enhance efficiency of CO2 reduction. This review covers literature in this field, particularly the studies about the photocatalytic system, TiO2 Z-scheme heterojunction composites, and use of transition metals for CO2 photoreduction. Lastly, challenges and opportunities are described to open a new era in engineering and attain good performances with semiconductor materials for photocatalytic CO2 reduction.


Assuntos
Dióxido de Carbono , Titânio , Catálise , Semicondutores
13.
Eur Radiol ; 31(4): 2392-2404, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32974686

RESUMO

OBJECTIVES: To systematically review studies on the diagnostic accuracy of spleen stiffness measurement (SSM) for the detection of clinical significant portal hypertension (CSPH), severe portal hypertension (SPH), esophageal varices (EV), and high-risk esophageal varices (HREV) in patients with chronic liver diseases (CLD). METHODS: Through a systematic search, we identified 32 studies reporting the accuracy of SSM for the diagnosis of portal hypertension (PH) and/or EV in adults with CLD. A bivariate random-effects model was performed to estimate pooled sensitivity, specificity, likelihood ratio, positive predictive value (PPV), negative predictive value (NPV), and diagnostic odds ratios (DOR). The clinical utility of SSM was evaluated by Fagan plot. RESULTS: A total of 32 studies assessing 3952 patients were included in this meta-analysis. The pooled sensitivities of SSM were 0.85 (95% confidence interval (CI), 0.69-0.93) for CSPH; 0.84 (95% CI, 0.75-0.90) for SPH; 0.90 (95% CI, 0.83-0.94) for any EV; and 0.87 (95% CI, 0.77-0.93) for HREV. The pooled specificities of SSM were 0.86 (95% CI, 0.74-0.93) for CSPH; 0.84 (95% CI, 0.72-0.91) for SPH; 0.73 (95% CI, 0.66-0.79) for EV; and 0.66 (95% CI, 0.53-0.77) for HREV. Summary PPV and NPV of SSM for detecting HREV were 0.54 (95% CI, 0.47-0.62) and 0.88 (95% CI, 0.81-0.95), respectively. CONCLUSIONS: Our meta-analysis suggests that SSM could be used as a helpful surveillance tool in management of CLD patients and was quite useful for ruling out the presence of HREV thereby avoiding unnecessary endoscopy. KEY POINTS: • SSM could be used to rule out the presence of HREV in patients with CLD thereby avoiding unnecessary endoscopy. • SSM has significant diagnostic value for CSPH and SPH with high sensitivity and specificity in patients with CLD. • SSM could be used as a helpful surveillance tool for clinicians managing CLD patients.


Assuntos
Técnicas de Imagem por Elasticidade , Varizes Esofágicas e Gástricas , Hipertensão Portal , Adulto , Varizes Esofágicas e Gástricas/diagnóstico , Varizes Esofágicas e Gástricas/patologia , Humanos , Hipertensão Portal/complicações , Hipertensão Portal/patologia , Fígado/diagnóstico por imagem , Cirrose Hepática/complicações , Cirrose Hepática/patologia , Valor Preditivo dos Testes , Baço/diagnóstico por imagem , Baço/patologia
14.
Ann Behav Med ; 55(6): 505-519, 2021 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-33119732

RESUMO

BACKGROUND: An expanding number of mind-body therapies are being used to reduce the psychological burden of peoples living with human immunodeficiency virus (HIV). However, the effects on the immune system and mental health varied among studies. PURPOSE: This meta-analysis was conducted to summarize the randomized controlled trials to draw comprehensive conclusions regarding the psycho-immunological efficacy. METHODS: Random-effects models were used to assess the outcome of interest. Egger's tests were used to identify publication bias. Subgroup and meta-regression were used to explore potential moderators. This review was registered on the PROSPERO database (CRD42019148118). RESULTS: Nineteen randomized controlled trials with a total sample size of 1,300 were included in this meta-analysis. Regarding immune system outcome, mind-body therapy significantly improved CD4 T-cell counts (Cohen's d = 0.214, p = .027) and maintained (0.427, p = .049). In addition, baseline CD4 T-cell counts and years since HIV diagnosis significantly moderated the efficacy of mind-body practices on CD4 improvement (all ps < .001). Regarding mental health outcome, mind-body therapy significantly reduced stress, depression, and anxiety symptoms (0.422, p < .001; 0.506, p < .001, and 0.709, p < .001, respectively) while improving quality of life (0.67, p < .001). CONCLUSIONS: Meditation/yoga intervention could result in potential benefits with regard to improved CD4 T-cell counts immediately after the intervention and at long-term follow-up, while also improving their mental health. The cost-effective meditation/yoga intervention should be integrated into routine care for people living with HIV, especially for those with lower CD4 baseline and fewer years since diagnosis.


Assuntos
Infecções por HIV/imunologia , Infecções por HIV/terapia , Meditação , Saúde Mental , Terapias Mente-Corpo/psicologia , Yoga , Contagem de Linfócito CD4 , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
15.
Phys Chem Chem Phys ; 23(15): 9270-9279, 2021 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-33885065

RESUMO

Two-dimensional graphene-like hexagonal borophene sheets (HBSs) have a thermodynamically unsteady configuration since boron has one electron less than the carbon in graphene. To overcome this problem, we proposed a novel 2D graphene-like HBS oxide (h-B3O) in theory, which is designed by substituting partial boron atoms in a HBS with oxygen atoms. Molecular dynamics simulations indicate that h-B3O has good thermal stability. Besides, we also explored the potential of h-B3O monolayers as anodes for Li-ion batteries (LIBs) and Na-ion batteries (NIBs) by using first-principles calculations. The results indicated that the h-B3O monolayer has high adsorption energies (-2.33/-1.70 eV for Li/Na), low diffusion barriers (0.67/0.42 eV for Li/Na) and suitable average open-circuit voltages (0.36/0.32 V for LIBs/NIBs). Particularly, h-B3O has a large theoretical specific capacity of 1161 mA h g-1 for LIBs. Thus, benefiting from these characteristics, the h-B3O monolayer is considered as a promising candidate for an anode material for LIBs/NIBs.

16.
Ecotoxicol Environ Saf ; 217: 112209, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33853018

RESUMO

By using Na2S as a sulfur source, sulfur-doped MnFe2O4 was prepared using one-step solvent thermal method and utilized to remove hexavalent chromium. The materials were characterized through scanning electron microscopy, transmission electron microscopy, high-resolution TEM, X-ray diffraction, Fourier-transform infrared spectroscopy, Brunauer-Emmett-Teller method, zeta potential test, vibrating sample magnetometry, and X-ray photoelectron spectroscopy. When the pH was 3, the adsorption capacity of MnFe2O4/FeSX-0.5 to Cr(VI) was 43.36 mg/g, which was roughly five times that of MnFe2O4 (8.90 mg/g). MnFe2O4/FeSX-0.5 and MnFe2O4 fitted the Freundlich and pseudo-second-order kinetic models well. The electrochemical test analysis results showed that MnFe2O4/FeSX had a faster MnFe2O4 electron transfer rate and higher electron transfer capacity than MnFe2O4, and thus promoted the reduction of Cr(VI) to Cr(III). This finding could be attributed to the lower electronegativity of the sulfur element than the oxygen element. In addition, the formation of additional FeSX through sulfur doping improved the Cr(VI) removal ability of the prepared materials. The XPS and desorption results showed that more than 80% of the adsorbed Cr(VI) were reduced to Cr(III), which indicated that reduction was an important mechanism for Cr(VI) removal. This study verified that sulfur-doped manganese ferrite can be utilized in the high-efficiency removal of Cr(VI).


Assuntos
Cromo/química , Poluentes Químicos da Água/química , Adsorção , Cromo/análise , Compostos Férricos , Concentração de Íons de Hidrogênio , Cinética , Compostos de Manganês , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Espectroscopia Fotoeletrônica , Espectroscopia de Infravermelho com Transformada de Fourier , Poluentes Químicos da Água/análise , Difração de Raios X
17.
AIDS Care ; 32(12): 1573-1580, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32188267

RESUMO

Despite abundant evidence on its safety, tolerability and cost-effectiveness, post-exposure prophylaxis (PEP) has not been officially approved for non-occupational use in China. This study aims to assess awareness of, willingness to use, and actual experience with PEP in gay, bisexual and other men who have sex with men (GBM) in China and to explore potential associations between demographic, behavioral, and psychosocial factors and PEP-related outcomes. We recruited a convenience sample through community venue-based strategies, peer referrals, and online advertisement in four cities of China in 2018. We used bivariable and multivariable logistic regression to test associations between potential predictors and PEP outcomes. Over 60% of men reported having heard of PEP prior to the survey, 70% would be willing to use it if exposed to HIV, and 6% reported having used PEP. Awareness of PEP was associated with higher education, more frequent HIV testing, knowing someone who seroconverted in the past two years, having sex with only men in the past six months, and lower perceived risk of HIV infection. PEP willingness was associated with more frequent HIV testing, being worried about becoming HIV infected, prior awareness and favorable attitudes towards PEP among friends. Findings suggest PEP is an underutilized diomedical HIV prevention intervention among GBM in China. Clinical guidance on non-occupational PEP use, as well as communication campaigns targeting social networks of GBM are needed to address barriers to PEP awareness and uptake.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/prevenção & controle , Infecções por HIV/psicologia , Conhecimentos, Atitudes e Prática em Saúde , Homossexualidade Masculina/psicologia , Profilaxia Pós-Exposição/estatística & dados numéricos , Profilaxia Pré-Exposição , Adulto , China , Homossexualidade Masculina/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Assunção de Riscos , Minorias Sexuais e de Gênero , Inquéritos e Questionários , Adulto Jovem
18.
BMC Infect Dis ; 20(1): 551, 2020 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-32727383

RESUMO

BACKGROUND: Talaromyces marneffei (TM) is a dimorphic fungus mainly prevalent in Southeast Asian countries, which often causes disseminated life-threatening infection. TM infection often occurs in HIV/AIDS patients even in the antiretroviral therapy (ART) era. However, there has as yet, not been a systematic analysis of the prevalence of TM infection in HIV-infected populations in Asia. METHODS: In this study, we searched Pubmed, Embase, Web of Science, China National Knowledge Infrastructure (CNKI), and WanFang from inception to 21 November 2018 for studies reporting TM infection in people living with HIV/AIDS (PLWHA). Our meta-analysis included studies investigating the prevalence of TM infection in PLWHA. Reviews, duplicate studies, and animal studies were excluded. A random effects model was used to estimate pooled prevalence, and meta-regression analysis was conducted to explore potential factors for heterogeneity. RESULTS: 159,064 patients with HIV infection in 33 eligible studies were included in our meta-analysis. The pooled prevalence of TM infection in PLWHA was 3.6%. Vietnam had the highest prevalence (6.4%), followed by Thailand (3.9%), China (3.3%), India (3.2%) and Malaysia (2.1%). In China, TM infection was most prevalent in South China (15.0%), while the burden in Southwest China was not very heavy (0.3%). CD4+ T-cell counts below 200 cells/mm3 contributed to the increased risk of TM infection in PLWHA (OR 12.68, 95%CI: 9.58-16.77). However, access to ART did not significantly decrease the risk of TM infection in PLWHA. CONCLUSIONS: The burden of TM infection in Asia is heavy, and varies from region to region. PLWHA in lower latitude areas are more likely to suffer from TM infection. Optimization of diagnostic tools and universal screening for TM in vulnerable people to ensure early case detection and prompt antifungal treatment should be considered.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/tratamento farmacológico , Infecções Oportunistas Relacionadas com a AIDS/epidemiologia , Fármacos Anti-HIV/uso terapêutico , HIV , Micoses/epidemiologia , Talaromyces/isolamento & purificação , Infecções Oportunistas Relacionadas com a AIDS/virologia , Sudeste Asiático/epidemiologia , Linfócitos T CD4-Positivos , China/epidemiologia , Humanos , Índia/epidemiologia , Contagem de Linfócitos , Micoses/microbiologia , Prevalência
19.
BMC Infect Dis ; 20(1): 410, 2020 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-32532212

RESUMO

BACKGROUND: Current WHO guidelines (2018) recommend screening for cryptococcal antigen (CrAg) in HIV-infected persons with CD4+ T cell counts< 100 cells/µL, followed by pre-emptive antifungal therapy among CrAg positive (CrAg+) persons, to prevent cryptococcal meningitis related deaths. This strategy may also be considered for those persons with a CD4+ T cell count of < 200 cells/uL according the WHO guidelines. However, there is sparse evidence in the literature supporting CrAg screening and pre-emptive antifungal therapy in those HIV-infected persons with this CD4+ T cell counts< 200 cells/µL. METHOD: We conducted a meta-analysis using data extracted from randomized controlled studies (RCTs) and cohort studies found in a search of Pubmed, Web of Science, the Cochrane Library and the EMBASE/MEDLINE database. RESULTS: The pooled prevalence of CrAg positivity in HIV-infected persons with CD4+ T cell counts< 200 cells/µL was 5% (95%CI: 2-7). The incidence of CM in CrAg+ persons was 3% (95%CI: 1-6). Among those CrAg+ persons who did not receive pre-emptive treatment, or those who received placebo, the incidence of CM was 5% (95%CI: 2-9), whereas the incidence of CM among those who received pre-emptive antifungal therapy was 3% (95%CI: 1-6), which is a statistically significant reduction in incidence of 40% (RR: 7.64, 95%CI: 2.96-19.73, p < 0.00001). As for persons with CD4+ T cell counts between 101 ~ 200 cells/µL, the risk ratio for the incidence of CM among those receiving placebo or no intervention was 1.15, compared to those receiving antifungal treatment (95%CI: 0.16-8.13). CONCLUSIONS: In our meta-analysis the incidence of CM was significantly reduced by pre-emptive antifungal therapy in CrAg+ HIV-infected persons with CD4 <  200 cells/µL. However, more specific observational data in persons with CD4+ T cell counts between 101 ~ 200 cells/µL are required in order to emphasize specific benefit of CrAg screening and pre-emptive antifungal treating in CrAg+ persons with CD4+ T cell counts < 200 cells/µL.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/diagnóstico , Infecções Oportunistas Relacionadas com a AIDS/prevenção & controle , Antifúngicos/uso terapêutico , Meningite Criptocócica/diagnóstico , Meningite Criptocócica/prevenção & controle , Infecções Oportunistas Relacionadas com a AIDS/imunologia , Infecções Oportunistas Relacionadas com a AIDS/microbiologia , Antígenos de Fungos/sangue , Contagem de Linfócito CD4 , Cryptococcus/imunologia , Cryptococcus/isolamento & purificação , Humanos , Incidência , Programas de Rastreamento , Meningite Criptocócica/imunologia , Meningite Criptocócica/microbiologia , Prevalência
20.
BMC Public Health ; 20(1): 4, 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31906905

RESUMO

BACKGROUND: In China, addressing disparities in the HIV epidemic among men who have sex with men (MSM) requires targeted efforts to increase their engagement and retention in prevention. In an effort to advance MSM-friendly HIV services within China, and informed by community-based partnerships, we tested whether MSM who have ever versus never disclosed their same-sex behavior to healthcare providers (HCP) differ in sociodemographic and behavioral characteristics as well as the qualities of sexual health services each group would prefer to access. METHODS: We conducted a cross-sectional survey among HIV-negative MSM who went to MSM-focused voluntary counseling and testing clinics in four cities in China. The survey was anonymous and collected information on sociodemographic characteristics, testing behaviors, sexual-health related behavior, and sexual health service model preferences. RESULTS: Of 357 respondents, 68.1% participants had ever disclosed same-sex behavior to HCPs when seeking advice for sexual health. Younger age (aOR = 1.04; 95% CI: 1.01-1.08), and worry of HIV acquisition (aOR = 1.39; 95% CI: 1.05-1.84) were associated with higher odds of past disclosure. The availability of comprehensive sexual health services was one of the most valued characteristics of the ideal sexual health clinic. Those who ever disclosed and never disclosed differed significantly in their ranking of the importance of three out of ten dimensions: sexual health counseling services available (M = 3.99 vs. M = 3.65, p = .002), gay identity support available (M = 3.91 vs. M = 3.62, p = .016) and clinic collaborates with a gay CBO (M = 3.81 vs. M = 3.56, p = .036). CONCLUSIONS: Our hypothesis that MSM who had disclosed versus never disclosed same-sex behavior would differ in the value they placed on different dimensions of sexual health service was partially borne out. As health authorities in China decide on implementation models for pre-exposure prophylaxis (PrEP) delivery and specifically within which institutions to integrate PrEP services, the preferences of target populations should be considered to develop comprehensive, patient-centric and LGBT-friendly services.


Assuntos
Revelação/estatística & dados numéricos , Infecções por HIV/prevenção & controle , Homossexualidade Masculina/psicologia , Preferência do Paciente/estatística & dados numéricos , Minorias Sexuais e de Gênero/psicologia , Adulto , China , Cidades , Estudos Transversais , Pesquisas sobre Atenção à Saúde , Homossexualidade Masculina/estatística & dados numéricos , Humanos , Masculino , Assistência Centrada no Paciente/organização & administração , Relações Médico-Paciente , Minorias Sexuais e de Gênero/estatística & dados numéricos
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