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1.
Proc Natl Acad Sci U S A ; 121(25): e2400546121, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38857407

RESUMO

Reduction of carbon dioxide (CO2) by renewable electricity to produce multicarbon chemicals, such as ethylene (C2H4), continues to be a challenge because of insufficient Faradaic efficiency, low production rates, and complex mechanistic pathways. Here, we report that the rate-determining steps (RDS) on common copper (Cu) surfaces diverge in CO2 electroreduction, leading to distinct catalytic performances. Through a combination of experimental and computational studies, we reveal that C─C bond-making is the RDS on Cu(100), whereas the protonation of *CO with adsorbed water becomes rate-limiting on Cu(111) with a higher energy barrier. On an oxide-derived Cu(100)-dominant Cu catalyst, we reach a high C2H4 Faradaic efficiency of 72%, partial current density of 359 mA cm-2, and long-term stability exceeding 100 h at 500 mA cm-2, greatly outperforming its Cu(111)-rich counterpart. We further demonstrate constant C2H4 selectivity of >60% over 70 h in a membrane electrode assembly electrolyzer with a full-cell energy efficiency of 23.4%.

2.
J Am Chem Soc ; 146(29): 20379-20390, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39011931

RESUMO

Scarce and expensive iridium oxide is still the cornerstone catalyst of polymer-electrolyte membrane electrolyzers for green hydrogen production because of its exceptional stability under industrially relevant oxygen evolution reaction (OER) conditions. Earth-abundant transition metal oxides used for this task, however, show poor long-term stability. We demonstrate here the use of nitrogen-doped cobalt oxide as an effective iridium substitute. The catalyst exhibits a low overpotential of 240 mV at 10 mA cm-2 and negligible activity decay after 1000 h of operation in an alkaline electrolyte. Incorporation of nitrogen dopants not only triggers the OER mechanism switched from the traditional adsorbate evolution route to the lattice oxygen oxidation route but also achieves oxygen nonbonding (ONB) states as electron donors, thereby preventing structural destabilization. In a practical anion-exchange membrane water electrolyzer, this catalyst at anode delivers a current density of 1000 mA cm-2 at 1.78 V and an electrical efficiency of 47.8 kW-hours per kilogram hydrogen.

3.
Nano Lett ; 23(1): 107-115, 2023 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-36541945

RESUMO

In comparison to the well-developed proton-exchange-membrane fuel cells, anion-exchange-membrane fuel cells (AEMFCs) permit adoption of platinum-group-metal (PGM)-free catalysts due to the alkaline environment, giving a substantial cost reduction. However, previous AEMFCs have generally shown unsatisfactory performances due to the lack of effective PGM-free catalysts that can endure harsh fuel cell conditions. Here we report a plasma-assisted synthesis of high-quality nickel nitride (Ni3N) and zirconium nitride (ZrN) employing dinitrogen as the nitrogen resource, exhibiting exceptional catalytic performances toward hydrogen oxidation and oxygen reduction in an alkaline enviroment, respectively. A PGM-free AEMFC assembled by using Ni3N as the anode and ZrN as the cathode delivers power densities of 256 mW cm-2 under an H2-O2 condition and 151 mW cm-2 under an H2-air condition. Furthermore, the fuel cell shows no evidence of degradation after 25 h of operation. This work creates opportunities for developing high-performance and durable AEMFCs based on metal nitrides.


Assuntos
Níquel , Platina , Membranas , Membrana Celular , Ânions , Prótons
4.
Angew Chem Int Ed Engl ; 63(32): e202407613, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-38736299

RESUMO

Anion-exchange membrane fuel cells provide the possibility to use platinum group metal-free catalysts, but the anodic hydrogen oxidation reaction (HOR) suffers from sluggish kinetics and its source is still debated. Here, over nickel-tungsten (Ni-W) alloy catalysts, we show that the Ni : W ratio greatly governs the HOR performance in alkaline electrolyte. Experimental and theoretical studies unravel that alloying with W can tune the unpaired electrons in Ni, tailoring the potential of zero charge and the catalytic surface to favor hydroxyl adsorption (OHad). The OHad species coordinately interact with potassium (K+) ions, which break the K+ solvation sheath to leave free water molecules, yielding an improved connectivity of hydrogen-bond networks. Consequently, the optimal Ni17W3 alloy exhibits alkaline HOR activity superior to the state-of-the-art platinum on carbon (Pt/C) catalyst and operates steadily with negligible decay after 10,000 cycles. Our findings offer new understandings of alloyed HOR catalysts and will guide rational design of next-generation catalysts for fuel cells.

5.
J Am Chem Soc ; 145(31): 17485-17494, 2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37526148

RESUMO

Converting hydrogen chemical energy into electrical energy by fuel cells offers high efficiencies and environmental advantages, but ultrapure hydrogen (over 99.97%) is required; otherwise, the electrode catalysts, typically platinum on carbon (Pt/C), will be poisoned by impurity gases such as ammonia (NH3). Here we demonstrate remarkable NH3 resistivity over a nickel-molybdenum alloy (MoNi4) modulated by chromium (Cr) dopants. The resultant Cr-MoNi4 exhibits high activity toward alkaline hydrogen oxidation and can undergo 10,000 cycles without apparent activity decay in the presence of 2 ppm of NH3. Furthermore, a fuel cell assembled with this catalyst retains 95% of the initial peak power density even when NH3 (10 ppm)/H2 was fed, whereas the power output reduces to 61% of the initial value for the Pt/C catalyst. Experimental and theoretical studies reveal that the Cr modifier not only creates electron-rich states that restrain lone-pair electron donation but also downshifts the d-band center to suppress d-electron back-donation, synergistically weakening NH3 adsorption.

6.
PLoS Med ; 20(1): e1004091, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36595536

RESUMO

BACKGROUND: To inform policy and implementation that can enhance prevention and improve tuberculosis (TB) care cascade outcomes, this review aimed to summarize the impact of various interventions on care cascade outcomes for active TB. METHODS AND FINDINGS: In this systematic review and meta-analysis, we retrieved English articles with comparator arms (like randomized controlled trials (RCTs) and before and after intervention studies) that evaluated TB interventions published from January 1970 to September 30, 2022, from Embase, CINAHL, PubMed, and the Cochrane library. Commentaries, qualitative studies, conference abstracts, studies without standard of care comparator arms, and studies that did not report quantitative results for TB care cascade outcomes were excluded. Data from studies with similar comparator arms were pooled in a random effects model, and outcomes were reported as odds ratio (OR) with 95% confidence interval (CI) and number of studies (k). The quality of evidence was appraised using GRADE, and the study was registered on PROSPERO (CRD42018103331). Of 21,548 deduplicated studies, 144 eligible studies were included. Of 144 studies, 128 were from low/middle-income countries, 84 were RCTs, and 25 integrated TB and HIV care. Counselling and education was significantly associated with testing (OR = 8.82, 95% CI:1.71 to 45.43; I2 = 99.9%, k = 7), diagnosis (OR = 1.44, 95% CI:1.08 to 1.92; I2 = 97.6%, k = 9), linkage to care (OR = 3.10, 95% CI = 1.97 to 4.86; I2 = 0%, k = 1), cure (OR = 2.08, 95% CI:1.11 to 3.88; I2 = 76.7%, k = 4), treatment completion (OR = 1.48, 95% CI: 1.07 to 2.03; I2 = 73.1%, k = 8), and treatment success (OR = 3.24, 95% CI: 1.88 to 5.55; I2 = 75.9%, k = 5) outcomes compared to standard-of-care. Incentives, multisector collaborations, and community-based interventions were associated with at least three TB care cascade outcomes; digital interventions and mixed interventions were associated with an increased likelihood of two cascade outcomes each. These findings remained salient when studies were limited to RCTs only. Also, our study does not cover the entire care cascade as we did not measure gaps in pre-testing, pretreatment, and post-treatment outcomes (like loss to follow-up and TB recurrence). CONCLUSIONS: Among TB interventions, education and counseling, incentives, community-based interventions, and mixed interventions were associated with multiple active TB care cascade outcomes. However, cost-effectiveness and local-setting contexts should be considered when choosing such strategies due to their high heterogeneity.


Assuntos
Tuberculose , Humanos , Tuberculose/diagnóstico , Tuberculose/epidemiologia , Tuberculose/prevenção & controle , Aconselhamento , Motivação
7.
Sex Health ; 19(4): 357-366, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35614024

RESUMO

BACKGROUND: Social network approaches to testing allow individuals (indexes) to distribute tests to social networks (alters). This quasi-experimental study compared two social network-based testing strategies in promoting human immunodeficiency virus (HIV) testing among Chinese gay, bisexual, and other men who have sex with men (GBMSM). METHODS: GBMSM aged ≥18years were recruited from Guangzhou, China. From May to September 2019, indexes could distribute blood-based HIV/syphilis dual self-testing kits to people within their social network. Indexes recruited from October 2019 to January 2020 could send HIV testing cards to their social networks for free facility-based tests. Alters were encouraged to upload a photo verification of test results. Indexes and alters received incentives during both periods. RESULTS: There were 245 participants who were assessed for eligibility and 208/245 (84.9%) were eligible. 106 and 102 indexes were recruited in the secondary distribution and testing card arms respectively. 154/208 (74.0%) completed follow up at 1 month. 92 indexes in the secondary distribution arm self-reported distributions to 179 unique alters, and 62 in the testing card arm to 26 unique alters. An average of 1.95 (standard deviation [s.d.]=1.90) HIV/syphilis dual self-tests and 0.42 (s.d.=0.78) HIV testing cards were distributed, generating a risk difference of 1.53 (95% confidence interval [CI] 1.09, 1.96). Indexes self-identifying as gay (P =0.007) or having previously tested (P =0.02) distributed more tests. Secondary distribution cost less per alter tested (USD120 vs USD9408). CONCLUSIONS: Secondary distribution engaged more GBMSM to distribute tests and reached more GBMSM to test compared to referral cards, suggesting advantage in facilitating testing uptake among Chinese GBMSM.


Assuntos
Infecções por HIV , Minorias Sexuais e de Gênero , Sífilis , China , Infecções por HIV/diagnóstico , Teste de HIV , Homossexualidade Masculina , Humanos , Masculino , Encaminhamento e Consulta , Autoteste , Sífilis/diagnóstico
8.
Angew Chem Int Ed Engl ; 61(42): e202208040, 2022 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-35831687

RESUMO

Platinum on carbon (Pt/C) catalyst is commercially adopted in fuel cells but it undergoes formidable active-site poisoning by carbon monoxide (CO). In particular, given the sluggish kinetics of hydrogen oxidation reaction (HOR) in anion-exchange membrane fuel cell (AEMFC), the issues of Pt poisoning and slow rate would combine mutually, notably worsening the device performances. Here we overcome these challenges through incorporating cobalt (Co) into molybdenum-nickel alloy (MoNi4 ), termed Co-MoNi4 , which not only shows superior HOR activity over the Pt/C catalyst in alkali, but more intriguingly exhibits excellent CO tolerance with only small activity decay after 10 000 cycles in the presence of 500 parts per million (ppm) CO. When feeding with CO (250 ppm)/H2 , the AEMFC assembled by this catalyst yields a peak power density of 394 mW cm-2 , far exceeding the Pt/C catalyst. Experimental and computational studies reveal that weakened CO chemisorption originates from the electron-deficient Ni sites after Co incorporation that suppresses d→CO 2π* back-donation.

9.
Clin Infect Dis ; 73(7): e2251-e2257, 2021 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-32588883

RESUMO

BACKGROUND: Social media and secondary distribution (distributing self-testing kits by indexes through their networks) both show strong promise to improve human immunodeficiency virus (HIV) self-testing uptake. We assessed an implementation program in Zhuhai, China, which focused on the secondary distribution of HIV/syphilis self-test kits among men who have sex with men (MSM) via social media. METHODS: Men aged ≥16 years, born biologically male, and ever had sex with another man were recruited as indexes. Banner ads on a social media platform invited the participants to apply for up to 5 self-test kits every 3 months. Index men paid a deposit of US$15/kit refundable upon submitting a photograph of a completed test result via an online submission system. They were informed that they could distribute the kits to others (referred to as "alters"). RESULTS: A total of 371 unique index men applied for 1150 kits (mean age, 28.7 [standard deviation, 6.9] years), of which 1141 test results were returned (99%). Among them, 1099 were valid test results; 810 (74%) were from 331 unique index men, and 289 tests (26%) were from 281 unique alters. Compared to index men, a higher proportion of alters were naive HIV testers (40% vs 21%; P < .001). The total HIV self-test reactivity rate was 3%, with alters having a significantly higher rate than indexes (5% vs 2%; P = .008). A total of 21 people (3%) had a reactive syphilis test result. CONCLUSIONS: Integrating social media with the secondary distribution of self-test kits may hold promise to increase HIV/syphilis testing coverage and case identification among MSM.


Assuntos
Infecções por HIV , Minorias Sexuais e de Gênero , Mídias Sociais , Sífilis , Adulto , China/epidemiologia , HIV , Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia , Homossexualidade Masculina , Humanos , Masculino , Programas de Rastreamento , Autoteste , Sífilis/diagnóstico , Sífilis/epidemiologia
10.
Biol Reprod ; 104(2): 430-444, 2021 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-33571374

RESUMO

Corpus luteum (CL) plays a critical role in mammalian reproductive physiology. Its dysfunction will lead to infertility or habitual abortion. In the current study, by use of melatonin specific membrane receptor 2 (MT2) knocking out (KO) mice model combined with RNA-Seq, immunohistochemistry, and immunofluorescence analyses, the genes of melatonin synthetic enzyme arylalkylamine N-acetyltransferase (AANAT) and MT2 were identified to strongly express in the CL of sows and mice. KO MT2 significantly impaired the reproductive performance in mice indicated by the reduced litter sizes. Melatonin treatment elevated the progesterone production in sows suggesting the improved CL function. Mechanistic analysis showed that melatonin upregulated a set of progesterone synthesis-related genes including cytochrome P450 family 11 subfamily A member 1 (Cyp11a1), aldo-keto reductase family 1, member C18 (Akr1c18), isopentenyl-diphosphate delta isomerase 1 (Idi1), and luteinizing hormone/choriogonadotropin receptor (Lhcgr). The upregulation of these genes directly related to the increased progesterone production. The regulatory effects of melatonin on these gene expressions were mediated by MT2 and MT2KO diminished the effects of melatonin in this respect. Thus, the presence of melatonergic system of AANAT, melatonin, and its receptor MT2 in CL is essential for reproductive success in mammals.


Assuntos
Arilalquilamina N-Acetiltransferase/metabolismo , Transtornos de Estresse por Calor/veterinária , Melatonina/metabolismo , Melatonina/farmacologia , Receptores de Melatonina/metabolismo , Ração Animal , Animais , Arilalquilamina N-Acetiltransferase/genética , Células Cultivadas , Relação Dose-Resposta a Droga , Feminino , Fertilidade , Regulação da Expressão Gênica/efeitos dos fármacos , Transtornos de Estresse por Calor/metabolismo , Células Lúteas/efeitos dos fármacos , Células Lúteas/metabolismo , Melatonina/administração & dosagem , Camundongos , Camundongos Knockout , Receptores de Melatonina/genética , Suínos
11.
J Med Internet Res ; 23(6): e24303, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34061035

RESUMO

BACKGROUND: Social network-based strategies can expand HIV/syphilis self-tests among men who have sex with men (MSM). Sexual health influencers are individuals who are particularly capable of spreading information about HIV and other sexually transmitted infections (STIs) within their social networks. However, it remains unknown whether a sexual health influencer can encourage their peers to self-test for HIV/syphilis. OBJECTIVE: The aims of this study were to examine the impact of MSM sexual health influencers on improving HIV/syphilis self-test uptake within their social networks compared to that of nonsexual health influencers. METHODS: In Zhuhai, China, men 16 years or older, born biologically male, who reported ever having had sex with a man, and applying for HIV/syphilis self-tests were enrolled online as indexes and encouraged to distribute self-tests to individuals (alters) in their social network. Indexes scoring >3 on a sexual health influencer scale were considered to be sexual health influencers (Cronbach α=.87). The primary outcome was the mean number of alters encouraged to test per index for sexual health influencers compared with the number encouraged by noninfluencers. RESULTS: Participants included 371 indexes and 278 alters. Among indexes, 77 (20.8%) were sexual health influencers and 294 (79.2%) were noninfluencers. On average, each sexual health influencer successfully encouraged 1.66 alters to self-test compared to 0.51 alters encouraged by each noninfluencer (adjusted rate ratio 2.07, 95% CI 1.59-2.69). More sexual health influencers disclosed their sexual orientation (80.5% vs 67.3%, P=.02) and were community-based organization volunteers (18.2% vs 2.7%, P<.001) than noninfluencers. More alters of sexual health influencers came from a rural area (45.5% vs 23.8%, P<.001), had below-college education (57.7% vs 37.1%, P<.001), and had multiple casual male sexual partners in the past 6 months (25.2% vs 11.9%, P<.001). CONCLUSIONS: Being a sexual health influencer was associated with encouraging more alters with less testing access to self-test for HIV/syphilis. Sexual health influencers can be engaged as seeds to expand HIV/syphilis testing coverage.


Assuntos
Infecções por HIV , Saúde Sexual , Minorias Sexuais e de Gênero , Sífilis , China/epidemiologia , Estudos Transversais , Feminino , Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia , Homossexualidade Masculina , Humanos , Masculino , Comportamento Sexual , Parceiros Sexuais , Inquéritos e Questionários , Sífilis/diagnóstico , Sífilis/epidemiologia
12.
J Viral Hepat ; 27(2): 135-142, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31571341

RESUMO

Stigma against people with hepatitis B virus (HBV) is a barrier to prevention, diagnosis and treatment of HBV in China. Our study examined an innovative intervention to reduce HBV stigma among men who have sex with men (MSM) in China. We extracted data from a randomized controlled trial conducted in May 2018, where the intervention consisted of crowdsourced images and videos to promote viral hepatitis testing and reduce HBV stigma. HBV stigma was assessed using a 20-item scale at baseline and four weeks post-enrolment. Participants were divided into three groups based on their exposure to intervention: full exposure, partial exposure and no exposure. Linear regression was used to determine associations between baseline stigma and participant characteristics. Data from 470 MSM were analysed. Mean participant age was 25 years old and 56% had less education than a college bachelor's degree. Full exposure to intervention was associated with significant stigma reduction (adjusted beta = -3.49; 95% CI = -6.11 to -0.87; P = .01), while partial exposure led to stigma reduction that was not statistically significant. The mean stigma score was 50.6 (SD ± 14.7) at baseline, and stigma was most prominent regarding physical contact with HBV carriers. Greater HBV stigma was associated with not having a recent doctor's visit (adjusted beta = 4.35, 95% CI = 0.19 to 8.52; P = .04). In conclusion, crowdsourcing can decrease HBV stigma among MSM in China and may be useful in anti-stigma campaigns for vulnerable populations in low- and middle-income countries.


Assuntos
Crowdsourcing , Hepatite B/prevenção & controle , Hepatite B/psicologia , Minorias Sexuais e de Gênero/psicologia , Estigma Social , Adulto , China/epidemiologia , Hepatite B/epidemiologia , Homossexualidade Masculina , Humanos , Masculino , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Retrospectivos , Adulto Jovem
13.
BMC Infect Dis ; 20(1): 732, 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-33028241

RESUMO

BACKGROUND: Adolescent sexual debut and non-consensual sex have been linked to higher sexual risk and STI infection in adulthood among men who have sex with men (MSM) in high-income countries. This study aimed to examine adolescent and non-consensual anal sexual debut among Chinese MSM and to evaluate factors associated with adolescent sexual debut and non-consensual anal sex. METHODS: A cross-sectional study was conducted recently among Chinese men assigned male sex at birth, ≥18 years old, and who had ever engaged in anal sex with a man. Participants answered questions regarding socio-demographics, condomless sex, age at anal sexual debut with a man, and whether the first anal sex was consensual. Factors associated with an adolescent sexual debut (< 18 years old) and non-consensual sex at sexual debut were evaluated. We defined adolescent sexual debut as having anal sex with another man at 17 years old or younger, and the participants were asked whether their first male-to-male anal sex was non-consensual. RESULTS: Overall, 2031 eligible men completed the survey. The mean age of sexual debut was 20.7 (SD = 4.3) years old. 17.6% (358/2031) of men reported adolescent sexual debut, and 5.0% (101/2031) reported a non-consensual sexual debut. The adolescent sexual debut was associated with having more male sexual partners (adjusted OR 1.10, 95% CI 1.06-1.15) and condomless anal sex in the last three months (AOR = 1.71, 95% CI 1.34-2.18). MSM whose sexual debut was non-consensual were more likely to have condomless anal sex (AOR = 1.76, 95% CI 1.17-2.66), and to have reported an adolescent sexual debut (AOR = 2.72, 95% CI 1.75-4.21). CONCLUSIONS: Many Chinese MSM reported adolescent sexual debut and non-consensual sex, both of which are associated with sexual risk behaviors and drive STI transmission. These findings highlight the need for designing tailored interventions for MSM who experienced adolescent sexual debut and non-consensual sex at debut.


Assuntos
Homossexualidade Masculina/estatística & dados numéricos , Comportamento Sexual/estatística & dados numéricos , Adolescente , Adulto , Povo Asiático , China , Preservativos , Estudos Transversais , Infecções por HIV/patologia , Humanos , Masculino , Razão de Chances , Assunção de Riscos , Inquéritos e Questionários , Adulto Jovem
14.
Mar Drugs ; 18(11)2020 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-33172133

RESUMO

Four new purified polysaccharides (PAP) were isolated and purified from the Enteromorpha prolifera by alkali extraction, and further characterization was investigated. Their average molecular weights of PAP-1, PAP-2, PAP-3, and PAP-4 were estimated as 3.44 × 104, 6.42 × 104, 1.20 × 105, and 4.82 × 104 Da, respectively. The results from monosaccharide analysis indicated that PAP-1, PAP-2, PAP-3 were acidic polysaccharides and PAP-4 was a neutral polysaccharide. PAP-1 and PAP-2 mainly consist of galacturonic acid, while PAP-3 and PAP-4 mainly contained rhamnose. Congo red test showed that no triple helical structure was detected in the four polysaccharides. The antioxidant activities were investigated using 1,1-diphenyl-2-picrylhydrazyl (DPPH), Superoxide, and 2, 2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical assay. In vitro antitumor activities were evaluated by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. PAP-1 exhibited relatively stronger antioxidant activities among the four polysaccharides in a dose-dependent manner. At a concentration of 1.00 mg/mL, the antioxidant activities of PAP-1 on the DPPH radical scavenging rate, superoxide anion radical scavenging rate, and ABTS radical rate at 1.00 mg/mL were 56.40%, 54.27%, and 42.07%, respectively. They also showed no significant inhibitory activity against MGC-803, HepG2, T24, and Bel-7402 cells. These investigations of polysaccharides provide a scientific basis for the use of E. prolifera as an ingredient in functional foods and medicines.


Assuntos
Antioxidantes/farmacologia , Clorófitas/metabolismo , Polissacarídeos/farmacologia , Álcalis/química , Animais , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Antioxidantes/isolamento & purificação , Fracionamento Químico , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Eritrócitos/patologia , Hemólise/efeitos dos fármacos , Células Hep G2 , Humanos , Peróxido de Hidrogênio/toxicidade , Camundongos Endogâmicos ICR , Estrutura Molecular , Polissacarídeos/isolamento & purificação , Relação Estrutura-Atividade
15.
J BUON ; 23(5): 1472-1480, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30570875

RESUMO

PURPOSE: Ewing's sarcoma (ES) is a highly aggressive malignant bone and soft tissue neoplasm. The purpose of our study was to identify candidate biomarkers of ES and uncover their potential molecular mechanisms. METHODS: The gene expression profiles of GSE45544 and GSE73166 were downloaded from Gene Expression Omnibus (GEO) database. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes pathway (KEGG) enrichment analyses were performed based on the Database for Annotation, Visualization and Integrated Discovery (DAVID) database, protein-protein interaction (PPI) network was constructed, and hub genes of the differentially expressed genes (DEGs) were identified by Cytoscape software. RESULTS: 586 DEGs in total were identified in ES, and the top up-regulated genes were extremely potent as ES biomarkers. GO function analysis data showed that these DEGs were significantly enriched in DNA translation, nucleus, and protein binding. KEGG pathway analysis revealed that DEGs were enriched in the pathways involved in cancer, HTLV-I infection, viral carcinogenesis, ribosome, and cell cycle. PPI network showed that most of the hub genes were for ribosomal proteins, associated in some way with the biological process of ES. CONCLUSIONS: In conclusion, we identified the DEGs and hub genes which could promote our comprehension of detailed mechanisms involved in the development of ES.


Assuntos
Neoplasias Ósseas/genética , Sarcoma de Ewing/genética , Neoplasias Ósseas/patologia , Biologia Computacional , Perfilação da Expressão Gênica , Humanos , Sarcoma de Ewing/patologia
16.
Cell Physiol Biochem ; 39(5): 1679-1694, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27643888

RESUMO

BACKGROUND: Tumor necrosis factor α (TNFα) antagonists, namely, golimumab, adalimumab, infliximab, etanercept and certolizumab have been prescribed to alleviate and treat ankylosing spondylitis (AS). However, the lack of comparative evidence does not enable us to make constructive recommendations particularly for AS patient populations. METHODS: Eligible controlled trials regarding the above 5 anti-TNFα therapies were searched electronically through PubMed, Embase and Cochrane until April 1, 2015. Odds ratios (ORs) were estimated and compared for efficacy (ASAS20, ASAS40, ASAS5/6 responses and ASAS partial remission) and acceptability (serious adverse effects (SAE)) among the anti-TNFα reagents. RESULTS: Totally, 25 trials with 2989 participants were incorporated in this mixed treatment comparison. All the 5 TNFα blockers achieved better ASAS20, ASAS40, ASAS5/6 and ASAS-PR responses than the placebo. Furthermore, there was no significant distinction existed among inter-drug comparisons, except that unfavorable effects induced by certolizumab seemed to be less severe than those by etanercept (OR = 0.22, 95% CI: 0.05-0.93). Apart from that, etanercept was estimated to arrive at the most favorable ASAS20 response (90.6%) and SAE (83.6%), while infliximab seemed to accomplish the best ASAS40 (83.6%) and ASAS-PR responses (77.3%). In addition, adalimumab was estimated to rank the highest ASAS5/6 response (75.0%). CONCLUSIONS: Etanercept, infliximab and adalimumab might be prioritized among the commonly recognized 5 anti-TNFα therapies specific for AS patients, though existing evidence did not suffice to confirm significant superiority among the above 5 anti-TNFα reagent.


Assuntos
Adalimumab/uso terapêutico , Anti-Inflamatórios não Esteroides/uso terapêutico , Anticorpos Monoclonais/uso terapêutico , Certolizumab Pegol/uso terapêutico , Etanercepte/uso terapêutico , Infliximab/uso terapêutico , Espondilite Anquilosante/tratamento farmacológico , Ensaios Clínicos como Assunto , Expressão Gênica , Humanos , Razão de Chances , Espondilite Anquilosante/genética , Espondilite Anquilosante/imunologia , Espondilite Anquilosante/patologia , Resultado do Tratamento , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia
17.
Nano Lett ; 14(2): 1080-4, 2014 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-24475905

RESUMO

We report an all-nanowire based flexible Li-ion battery full cell, using homologous Mn2O3 and LiMn2O4 nanowires for anodes and cathodes, respectively. The same precursors, MnOOH nanowires, are transformed from hydrothermally grown MnO2 nanoflakes and directly attached on Ti foils via reaction with poly(vinyl pyrrolidone). The Mn2O3 anode and LiMn2O4 cathode are subsequently formed by thermal annealing and reaction with lithium salt, respectively. The one-dimensional nanowire structures provide short lithium-ion diffusion path, good charge transport, and volume flexibility for Li(+) intercalation/deintercalation, thus leading to good rate capability and cycling performance. As proof-of-concept, the Mn2O3 nanowire anode delivers an initial discharge capacity of 815.9 mA h g(-1) at 100 mA g(-1) and maintains a capacity of 502.3 mA h g(-1) after 100 cycles. The LiMn2O4 nanowire cathodes show a reversible capacity of 94.7 mA h g(-1) at 100 mA g(-1) and high capacity retention of ∼ 96% after 100 cycles. Furthermore, a flexible Mn2O3//LiMn2O4 lithium ion full cell is fabricated, with an output voltage of >3 V, low thickness of 0.3 mm, high flexibility, and a specific capacity of 99 mA h g(-1) based on the total weight of the cathode material. It also exhibits good cycling stability with a capacity of ∼ 80 mA h g(-1) after 40 charge/discharge cycles.


Assuntos
Fontes de Energia Elétrica , Eletrodos , Lítio/química , Compostos de Manganês/química , Manganês/química , Nanofios/química , Óxidos/química , Transferência de Energia , Desenho de Equipamento , Análise de Falha de Equipamento , Íons , Teste de Materiais , Nanofios/ultraestrutura
18.
Front Pediatr ; 12: 1362104, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38529050

RESUMO

Introduction: To explore the factors affecting the success of testicular torsion manual reduction and the safety of subsequent conservative treatment after successful reduction. Methods: Clinical data of 66 patients with testicular torsion treated in our emergency department from February 2017 to February 2022 were retrospectively collected. Manual reduction without anesthesia was performed in 19 patients. Patients with successful manual reduction chose different subsequent treatments according to the wishes of themselves and their guardians, including continuing conservative treatment and surgical exploration. Relevant clinical data were collected and analyzed. Results: Manual reduction was successful in 11 patients (11/19). Seven of them chose to continue conservative treatment, and four underwent surgical exploration immediately. Among the 7 patients who were treated conservatively, 3 underwent surgical treatment due to scrotal discomfort or testicular torsion at different stages, and the remaining 4 patients showed no recurrence of torsion during follow-up. Compared with other patients, patients with successful manual reduction had the shorter duration of pain (p < 0.05). The time from visiting our hospital to surgery in patients who attempted manual reduction was slightly shorter than those who underwent surgery directly (p > 0.05). The testes of these 11 patients were all successfully preserved. Conclusions: The short duration of pain may contribute to the success of manual reduction, and manual reduction did not increase the preparation time before surgery. Due to the unpredictable risk of recurrence, immediate surgical treatment is still recommended, or postponed elective surgical treatment should be offered in the next days or weeks.

19.
ACS Appl Mater Interfaces ; 16(14): 17483-17492, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38556943

RESUMO

Interfacial metal-support interaction (MSI) significantly affects the dispersion of active metals on the surface of the catalyst support and impacts catalyst performance. Understanding MSI is crucial for developing highly active and stable catalysts with a low metal loading, particularly for noble metal catalysts. In this work, we synthesized LaRuxCr1-xO3 catalysts with low Ru loading (x = 0.005, 0.01, and 0.02) using the sol-gel self-combustion method. We found that all of the Ru atoms immediately above or below the metal-support interface are closely bonded to the perovskite LaCrO3 surface lattice through Ru-O bonds, enhancing the MSI via interfacial reaction and charge transfer mechanisms. We identified a variety of Ru species, including small 3D Ru nanoparticles, 2D dispersed Ru surface atoms, and even 0D Ru single atoms. These highly dispersed Ru species exhibit high activity and stability under dry reforming of methane (DRM) conditions. The LaRu0.01Cr0.99O3 catalyst with very low Ru loading (0.42 wt %) was stable over a 50 h DRM test and the carbon deposition was negligible. The CH4 and CO2 conversions at 750 °C reached 83 and 86%, respectively, approaching the theoretical thermodynamic equilibrium values.

20.
Diabetes Care ; 47(2): 225-232, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38048487

RESUMO

OBJECTIVE: Patients with severe hypoglycemia (SH) or diabetic ketoacidosis (DKA) experience high hospital readmission after being discharged. Cognitive impairment (CI) may further increase the risk, especially in those experiencing an interruption of medical care after discharge. This study examined the effect modification role of postdischarge care (PDC) on CI-associated readmission risk among U.S. adults with diabetes initially admitted for DKA or SH. RESEARCH DESIGN AND METHODS: We used the Nationwide Readmissions Database (NRD) (2016-2018) to identify individuals hospitalized with a diagnosis of DKA or SH. Multivariate Cox regression was used to compare the all-cause readmission risk at 30 days between those with and without CI identified during the initial hospitalization. We assessed the CI-associated readmission risk in the patients with and without PDC, an effect modifier with the CI status. RESULTS: We identified 23,775 SH patients (53.3% women, mean age 65.9 ± 15.3 years) and 140,490 DKA patients (45.8% women, mean age 40.3 ± 15.4 years), and 2,675 (11.2%) and 1,261 (0.9%), respectively, had a CI diagnosis during their index hospitalization. For SH and DKA patients discharged without PDC, CI was associated with a higher readmission risk of 23% (adjusted hazard ratio [aHR] 1.23, 95% confidence interval 1.08-1.40) and 35% (aHR 1.35, 95% confidence interval 1.08-1.70), respectively. However, when patients were discharged with PDC, we found PDC was an effect modifier to mitigate CI-associated readmission risk for both SH and DKA patients (P < 0.05 for all). CONCLUSIONS: Our results suggest that PDC can potentially mitigate the excessive readmission risk associated with CI, emphasizing the importance of postdischarge continuity of care for medically complex patients with comorbid diabetes and CI.


Assuntos
Diabetes Mellitus , Cetoacidose Diabética , Hipoglicemia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Assistência ao Convalescente , Diabetes Mellitus/epidemiologia , Cetoacidose Diabética/epidemiologia , Cetoacidose Diabética/terapia , Cetoacidose Diabética/complicações , Hipoglicemia/terapia , Hipoglicemia/etiologia , Alta do Paciente , Readmissão do Paciente , Estudos Retrospectivos
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