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1.
Sex Transm Dis ; 51(2): 118-124, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37934141

RESUMO

BACKGROUND: Chinese gay, bisexual, and other men who have sex with men (GBMSM) face discrimination in many facility-based health services, thus increasing the importance of online engagement. The purpose of this study was to examine online GBMSM community spaces and implications for HIV/sexually transmitted disease prevention services. METHODS: We conducted a total of 6 online focus group discussions with Chinese GBMSM from Guangdong province on the chat-based platform WeChat in 2021. Focus group discussions were asynchronous, and participants were able to provide and map out online spaces that they had participated in and share their perspectives on online engagement. Data were analyzed through framework analysis. RESULTS: Overall, 48 participants participated. Most were mainly sexually attracted to men (n = 43; 90.0%) and never participated in in-person LGBTQ-related events (n = 29; 60.4%). Participants articulated a typology of online spaces along the axes of whether such spaces were Chinese platforms (vs. non-Chinese) or whether they were GBMSM-specific (vs. non-GBMSM-specific). Participants articulated several advantages of online spaces, including greater anonymity, opportunities for community building, sharing of sexual health information, and being able to meet other GBMSM more efficiently. Drawbacks included the lack of personal connection, lack of safety measures for youth, encountering deception and the use of fake profile pictures, and needing a virtual proxy network to access some websites. Participants provided suggestions to further improve their experiences of online spaces. CONCLUSIONS: Although broad-based, GBMSM-specific messaging can be implemented in Chinese, GBMSM-specific spaces, sexual health messaging may also reach niche GBMSM communities in a variety of non-GBMSM spaces.


Assuntos
Infecções por HIV , Minorias Sexuais e de Gênero , Infecções Sexualmente Transmissíveis , Masculino , Adolescente , Humanos , Homossexualidade Masculina , HIV , Grupos Focais , Infecções Sexualmente Transmissíveis/epidemiologia , Infecções Sexualmente Transmissíveis/prevenção & controle , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , China/epidemiologia
2.
ACS Appl Mater Interfaces ; 15(42): 48903-48912, 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37877332

RESUMO

Bacterial infection and insufficient neovascularization are two major obstacles to the healing of chronic wounds. Here, we present an antibacterial and proangiogenic dressing by encapsulating dimethyloxalylglycine (DMOG) in zeolitic imidazolate framework-8 (ZIF-8) and electrospinning it with gelatin-polycaprolactone (Gel-PCL). As Gel-PCL nanofibers degrade, ZIF-8 nanoparticles decompose, sequentially releasing bactericidal zinc ions and angiogenic DMOG molecules. This cascade process matches the wound-healing stages, ensuring suitable bioavailability and an effective duration of the active components while minimizing their side effects. In vitro, zinc ions released from the dressing (2.5% DMOG@ZIF-8) can eliminate over 90% of Escherichia coli and Staphylococcus aureus without compromising fibroblast cell proliferation and adhesion. In vivo, the dressing can heal skin wounds in Staphylococcus aureus-infected diabetic rats within 2 weeks, facilitated by the DMOG molecules discharged from ZIF-8 (loading rate 21.3%). Immunohistochemical analysis confirmed the regulated expression of factors by zinc ions and DMOG molecules. This work provides new insights into the design of multifunctional dressings for the treatment of chronic wounds.


Assuntos
Anti-Infecciosos , Diabetes Mellitus Experimental , Nanofibras , Zeolitas , Ratos , Animais , Gelatina/química , Zeolitas/química , Anti-Infecciosos/química , Antibacterianos/farmacologia , Cicatrização , Bandagens , Nanofibras/química , Staphylococcus aureus , Íons/farmacologia , Zinco/farmacologia
3.
ACS Appl Mater Interfaces ; 15(14): 17641-17652, 2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-37009854

RESUMO

Chronic wound healing is often impaired by bacterial infection and weak trans-epithelial potential. Patches with electrical stimulation and bactericidal activity may solve this problem. However, inconvenient power and resistant antibiotics limit their application. Here, we proposed a self-powered and intrinsic bactericidal patch based on a triboelectric nanogenerator (TENG). Electrospun polymer tribo-layers and a chemical vapor-deposited polypyrrole electrode are assembled as the TENG, offering the patch excellent flexibility, breathability, and wettability. Electrical stimulations by harvesting mechanical motions and positive charges on the polypyrrole surface kill over 96% of bacteria due to their synergistic effects on cell membrane disruption. Moreover, the TENG patch promotes infected diabetic rat skin wounds to heal within 2 weeks. Cell culture and animal tests suggest that electrical stimulation enhances gene expression of growth factors for accelerated wound healing. This work provides new insights into the design of wearable and multifunctional electrotherapy devices for chronic wound treatment.


Assuntos
Polímeros , Infecção dos Ferimentos , Animais , Ratos , Pirróis , Cicatrização , Antibacterianos/farmacologia , Eletrodos
4.
Cell Biosci ; 13(1): 30, 2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36782335

RESUMO

BACKGROUNDS: Botulinum toxin type A (BoNT/A) is extensively applied in spasticity and dystonia as it cleaves synaptosome-associated protein 25 (SNAP25) in the presynaptic terminals, thereby inhibiting neurotransmission. An increasing number of randomized clinical trials have suggested that glabellar BoNT/A injection improves depressive symptoms in patients with major depressive disorder (MDD). However, the underlying neuronal circuitry of BoNT/A-regulated depression remains largely uncharacterized. RESULTS: Here, we modeled MDD using mice subjected to chronic restraint stress (CRS). By pre-injecting BoNT/A into the unilateral whisker intrinsic musculature (WIM), and performing behavioral testing, we showed that pre-injection of BoNT/A attenuated despair- and anhedonia-like phenotypes in CRS mice. By applying immunostaining of BoNT/A-cleaved SNAP25 (cl.SNAP25197), subcellular spatial localization of SNAP25 with markers of cholinergic neurons (ChAT) and post-synaptic membrane (PSD95), and injection of monosynaptic retrograde tracer CTB-488-mixed BoNT/A to label the primary nucleus of the WIM, we demonstrated that BoNT/A axonal retrograde transported to the soma of whisker-innervating facial motoneurons (wFMNs) and subsequent transcytosis to synaptic terminals of second-order neurons induced central effects. Furthermore, using transsynaptic retrograde and monosynaptic antegrade viral neural circuit tracing with c-Fos brain mapping and co-staining of neural markers, we observed that the CRS-induced expression of c-Fos and CaMKII double-positive neurons in the ventrolateral periaqueductal grey (vlPAG), which sent afferents to wFMNs, was down-regulated 3 weeks after BoNT/A facial pre-administration. Strikingly, the repeated and targeted silencing of the wFMNs-projecting CaMKII-positive neurons in vlPAG with a chemogenetic approach via stereotactic injection of recombinant adeno-associated virus into specific brain regions of CRS mice mimicked the antidepressant-like action of BoNT/A pre-treatment. Conversely, repeated chemogenetic activation of this potential subpopulation counteracted the BoNT/A-improved significant antidepressant behavior. CONCLUSION: We reported for the first time that BoNT/A inhibited the wFMNs-projecting vlPAG excitatory neurons through axonal retrograde transport and cell-to-cell transcytosis from the injected location of the WIM to regulate depressive-like phenotypes of CRS mice. For the limited and the reversibility of side effects, BoNT/A has substantial advantages and potential application in MDD.

5.
Front Pharmacol ; 13: 1023450, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36419617

RESUMO

Background and purpose: Neutrophil extracellular traps (NETs) are special web-like structures that can be generated in both infectious and noninfectious diseases. Previous studies showed that reactive oxygen species (ROS) were crucial in the formation of NETs (NETosis). The purpose of this study is to evaluate the effect of (+)-borneol, an antioxidant, on NETosis. Methods: Human neutrophils were stimulated with phorbol-12-myristate-13-acetate (PMA) to induce NETosis in vitro. Neutrophils treated with (+)-borneol at three different time points (-30 min, 0, and 30 min) associated with PMA stimulation were used to examine the effect of (+)-borneol on the formation of NETs. The ROS generation of neutrophils was also measured to explore the potential mechanism of the inhibitory effect of (+)-borneol on NETosis. Results: (+)-Borneol pretreatment inhibited NETosis induced by PMA. Immunofluorescence staining visualized and confirmed the inhibitory effect. (+)-Borneol inhibited the burst of ROS in neutrophils caused by PMA. Suppressing NADPH oxidase or protein kinase C (PKC) eliminated the effect of (+)-borneol on NETosis. Moreover, inhibiting Toll-like receptor 2 (TLR2) led to increased NETosis which can be inhibited by (+)-borneol. Conclusion: (+)-Borneol decreases the ROS level in activated neutrophils and inhibits NETosis triggered by PMA stimulation in vitro. (+)-Borneol therapy may be effective in some NET-dependent conditions.

6.
J Food Sci ; 86(12): 5318-5328, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34796506

RESUMO

Fish myofibrillar protein is underutilized due to the formation of insoluble aggregates in low salt media. High pressure homogenization (HPH) at 20, 40, and 60 MPa for four passes was applied on bighead carp myofibrillar protein in order to modify its structure and interfacial properties. Changes in aggregation, conformation, solubility, emulsifying and foaming properties of myofibrillar protein were investigated. The aggregates of myofibrillar protein were obviously disrupted by HPH treatment. The size of myofibrillar protein aggregates became smaller and more uniform as the treating pressure increased, accompanied by notable decreases of cross-sectional height and Rq value in AFM image. Furthermore, the conformation of HPH-treated myofibrillar protein was unfolded into a flexible and open structure. α-helix and ß-sheet were converted into ß-turn and random coil. Surface hydrophobicity and zeta potential were strengthened, along with the exposure of sulfhydryl groups onto molecule surface. On the other hand, solubility, emulsifying activity index (EAI) and foaming capacity (FC) of HPH-treated myofibrillar protein were markedly enhanced with the increasing pressure. Especially after HPH treatment at 60 MPa, myofibrillar protein was almost dissolved in low salt media (solubility 91.86%) with 4.92 fold for EAI and 3.52 fold for FC. But there was little variation in emulsifying and foaming stabilities. These results suggested that HPH treatment has interesting potential to induce the dissociation and unfolding of myofibrillar protein in low salt media, therefore improving its interfacial properties. PRACTICAL APPLICATION: Carp myofibrillar protein was treated by high pressure homogenization (HPH). Aggregates of myofibrillar protein were disrupted into smaller size form. Conformation of myofibrillar protein was unfolded into open and loose structure. Emulsifying and foaming capacities of myofibrillar protein were improved. HPH treatment modified the structure and interfacial properties of myofibrillar protein.


Assuntos
Carpas , Animais , Estudos Transversais
7.
J Sci Food Agric ; 101(9): 3723-3731, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33305370

RESUMO

BACKGROUND: Gardenia (Gardenia jasminoides Ellis) husk rich in dietary fiber is a byproduct of fructus processing, and commonly discarded as waste. The husk was fractionated by sequential extraction into four fractions: water-soluble fiber (W-SF), acid-soluble fiber (Ac-SF), alkali-soluble fiber (Al-SF) and insoluble residue fiber (IRF). The aim of this study was to investigate the differences in structure and in vitro hypoglycemic effect of these fibers. RESULTS: Monosaccharide composition and Fourier transform infrared spectra showed that the major component might be pectin for W-SF and Ac-SF, xylan as well as pectin for Al-SF and cellulose for IRF. These fibers offered excellent water-holding capacity and swelling capacity, except that IRF was only slightly swellable in water. W-SF exhibited significantly higher capacities to adsorb glucose (2.408 mmol g-1 at a glucose concentration of 200 mmol L-1 ) and inhibit α-amylase activity (29.48-49.45% inhibition rate at a concentration of 4-8 mg mL-1 ), probably caused by the higher viscosity and hydration properties; while Ac-SF, Al-SF and IRF (especially Al-SF) were more effective in retarding the glucose diffusion across a dialysis membrane (34.97-41.67% at 20-30 min), which might be attributed to particle size and specific surface area. All the fibers could quench the intrinsic fluorescence of α-amylase to some degree. CONCLUSIONS: Dietary fiber from gardenia husk, especially W-SF, can be used as a potential hypoglycemic ingredient in diabetic functional foods. © 2020 Society of Chemical Industry.


Assuntos
Fibras na Dieta/análise , Gardenia/química , Hipoglicemiantes/química , Extratos Vegetais/química , Diálise , Glucose/química , Pectinas/química , Viscosidade , alfa-Amilases/antagonistas & inibidores , alfa-Amilases/química
8.
Oxid Med Cell Longev ; 2019: 2370862, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31346358

RESUMO

The present study was designed to estimate the antiosteoporotic activity of total phenylethanoid glycoside fraction isolated from C. deserticola (CDP) on rats induced by ovariectomy (OVX) as well as the related mechanisms. After 3 months of oral administration, the decreased bone mineral density, serum Ca, and P in OVX rats were recovered and the deteriorated trabecular bone microarchitecture was partly improved by CDP (60, 120, and 240 mg/kg) intervention, the activities of bone resorption markers were downregulated, and the bioactive of the bone formation index was upregulated; meanwhile, the content of MDA was declined, and GSH was increased by CDP treatment. Compositionally, 8 phenylethanoid glycoside compounds were identified in CDP, with the total contents quantified as 50.3% by using the HPLC method. Mechanistically, CDP declined the levels of TRAF6, RANKL, and RANK, thus suppressing RANKL/RANK/TRAF6-induced activation of downstream NF-κB and PI3K/AKT signaling pathways and ultimately preventing activities of the key osteoclastogenic proteins of NFAT2 and c-Fos. All of the above data implied that CDP exhibited beneficial effects on bone microstructure in ovariectomized rats, and these effects may be related to the NF-κB and PI3K/AKT signaling pathways which were triggered by the binding of RANKL, RANK, and TRAF6.


Assuntos
Osso e Ossos/efeitos dos fármacos , Cistanche/química , Glicosídeos/uso terapêutico , Ovariectomia/métodos , Animais , Feminino , Glicosídeos/farmacologia , Ratos
9.
ChemSusChem ; 5(12): 2315-8, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23143708

RESUMO

Same selectivity hides different pathways: The same apparent 4-electron process for the oxygen-reduction-reaction hides different pathways over carbon-supported cobalt oxide catalysts depending on the potential. At low overpotentials, the ORR intermediate HO(2) (-) preferably disproportionates to oxygen, whereas at high overpotentials the disproportionation and reduction reaction occur in parallel.


Assuntos
Carbono/química , Cobalto/química , Fontes Geradoras de Energia , Nanopartículas/química , Óxidos/química , Oxigênio/química , Catálise , Eletrodos , Microscopia Eletrônica de Transmissão , Oxirredução , Tamanho da Partícula , Porosidade , Propriedades de Superfície
10.
Huan Jing Ke Xue ; 33(6): 1979-86, 2012 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-22946185

RESUMO

Using the static opaque chamber method, a field experiment, located in the Key Field Station for Monitoring of Eco-Environment of Purple Soil of the Ministry of Agriculture of China in the farm of Southwest University (30 degrees 26'N, 106 degrees 26'E) in Chongqing, was conducted in situ for one year to study the effect of different tillage systems on CH4 and N2O emission from ago-ecosystems in a purple paddy soil. In this paper, four tillage treatments including conventional tillage with rice only system (CT), conventional tillage with rotation of rice and rape system (CTR), no-till and plain culture with rotation of rice and rape system (NTP) and no-till and ridge culture with rotation of rice and rape system (NTR) were selected as research objectives. The results showed that the annual CH4 and N2O emissions were mainly occurred in the rice growing period, and were about 77.6% and 55.0% of the total annual of them emitted from this period. The total annual CH4 under CT was higher than that of other treatments. The annual average flux of CH4[CH4, mg x (m2 x h)(-1)] order was CT (2.96 +/- 0.04) >NTR (1.83 +/- 0.21) >NTP (1.42 +/- 0.01) >CTR (0.96 +/- 0.09); the annual average flux of N2O[N2O, microg x (m2 x h)(-1)] order was CTR (123.6 +/- 47.1) > NTR (115.2 +/- 22.1) > NTP (100.5 +/- 25.8) > CT (81.3 +/- 13.5), and the total annual N2O under CTR was higher than that of CT. The global warming potentials (GWPs) of CH4 and N2O emissions under different tillage-cropping systems were assessed in an integrated way. The results showed that the integrated GWPs of CH4 and N2O emission were in the following sequence: CT > NTR > NTP > CTR, and CTR was the best treatment for decrease the integrated GWPs in this area.


Assuntos
Agricultura/métodos , Metano/análise , Óxido Nitroso/análise , Oryza/crescimento & desenvolvimento , Solo/análise , China , Ecossistema
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