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1.
BMC Pregnancy Childbirth ; 23(1): 392, 2023 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-37245038

RESUMO

BACKGROUND: Antiviral intervention in hepatitis B virus (HBV)-infected pregnant women can effectively reduce mother-to-child transmission. However, the immunological characteristics of pregnant women with chronic HBV infection and the effects of antiviral intervention during pregnancy on maternal immune response remain unknown. We aimed to investigate these effects by comparing mothers who received antiviral intervention during pregnancy with those who did not. METHODS: Pregnant women positive for hepatitis B surface antigen and hepatitis B e-antigen (HBsAg+ HBeAg+) were enrolled at delivery, including 34 received prophylactic antiviral intervention during pregnancy (AVI mothers) and 15 did not (NAVI mothers). T lymphocyte phenotypes and functions were analysed using flow cytometry. RESULTS: At delivery, maternal regulatory T cell (Treg) frequency in AVI mothers was significantly higher than that in NAVI mothers (P < 0.002), and CD4+ T cells in AVI mothers displayed a decreased ability to secrete IFN-γ (P = 0.005) and IL-21 (P = 0.043), but an increased ability to secrete IL-10 and IL-4 (P = 0.040 and P = 0.036), which represented a higher Treg frequency, enhanced Th2 response and suppressed Th1 response. Treg frequency among AVI mothers was correlated negatively with serum HBsAg and HBeAg levels. After delivery, the ability of CD4+ T cells or CD8+ T cells to secrete IFN-γ or IL-10 was similar and no significant difference in Treg frequency was found between the two groups. CONCLUSIONS: Prophylactic antiviral intervention during pregnancy has an effect on T cell immunity in pregnant women, which was characterised by increased maternal Treg frequency, enhanced Th2 response and suppressed Th1 response at delivery.


Assuntos
Hepatite B , Complicações Infecciosas na Gravidez , Feminino , Gravidez , Humanos , Vírus da Hepatite B , Antígenos de Superfície da Hepatite B , Antivirais/uso terapêutico , Antígenos E da Hepatite B , Interleucina-10/uso terapêutico , Gestantes , Linfócitos T CD8-Positivos , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Hepatite B/prevenção & controle , DNA Viral
2.
Exp Appl Acarol ; 77(1): 11-25, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30569394

RESUMO

In phytoseiid mites, the spermatophore is an intermediate, isolated structure where sperms are stored during mating. In the present study, the producing process of Phytoseiulus persimilis spermatophore is described in details. Its shape, and the number and shape of sperms inside, are also analyzed, each as affected by coupling time. Based on our results, the spermatophore of P. persimilis is pyriform, and is produced from the male genital opening within 3 min since mating started. When produced, the spermatophore is transferred along the capitular groove to the cheliceral base, where it is adhered to one of the two small holes at the bases of the chelicerae. Seminal fluid passes through the hole, the hollow spermatodactyl, the opening on the spermatodactyl tip, and enters the insemination pore to reach the spermatheca of the female. No sperm was observed in spermatophores obtained 5 min after mating started. The number of sperms increased in the next 10 min, reached its maximum (ca. 52 sperms per spermatophore), and then decreased. All sperms were released in 75 min after mating started. Sperms are slender in shape and on average 3.9 ± 0.3 µm long.


Assuntos
Ácaros/fisiologia , Comportamento Sexual Animal/fisiologia , Espermatozoides/fisiologia , Animais , Feminino , Inseminação , Masculino , Espermatogônias/fisiologia
3.
Angew Chem Int Ed Engl ; 57(1): 292-295, 2018 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-29125711

RESUMO

The first example of a direct dehydroxytrifluoromethoxylation of alcohols has been developed. This method generated an alkyl fluoroformate in situ from alcohols, followed by nucleophilic trifluoromethoxylation with trifluoromethyl arylsulfonate (TFMS) as the trifluoromethoxylation reagent. The reaction is operationally simple and scalable, and it proceeds under mild reaction conditions to provide access to a wide range of trifluoromethyl ethers from alcohols. In addition, this method is suitable for the late-stage trifluoromethoxylation of complex small molecules.

4.
Angew Chem Int Ed Engl ; 57(40): 13266-13270, 2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-30085396

RESUMO

A silver-promoted oxidative benzylic C-H trifluoromethoxylation has been reported for the first time. With trifluoromethyl arylsulfonate as the trifluoromethoxylation reagent, various arenes, having diverse functional groups, undergo trifluoromethoxylation of their benzylic C-H bonds to form trifluoromethyl ethers under mild reaction conditions. In addition, the trifluoromethoxylation and the fluorination of methyl groups of electron-rich arenes have been achieved to prepare α-fluorobenzyl trifluoromethyl ethers in one step.

5.
ACS Omega ; 7(19): 16352-16360, 2022 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-35601292

RESUMO

Novel Ce x Zr1-x O2 (x = 0.67, 0.8, 0.9, 1.0) catalysts were designed and synthesized by solvothermal, calcination, and sol-gel methods and were used to catalyze oxidation of soot from diesel vehicle exhaust. The influence of catalysts synthesized by different methods and Ce/Zr molar ratios on the performance was investigated. These catalysts were characterized by XRD, N2 adsorption-desorption, FT-IR, TEM, XPS, H2-temperature programmed reduction (TPR), and O2-temperature programmed desorption (TPD) techniques. The results indicated that Ce0.8Zr0.2O2 prepared by the calcination method has excellent activity and stability at low temperature. The soot ignition point is 322 °C, and the ratio of soot conversion reaches 90% at 497 °C, which is lower than that from the solvothermal and sol-gel methods. The XRD, Raman, SEM, XPS and H2-TPR results reveal that the structure and oxygen adsorption properties are crucial to soot oxidation activity, and Zr4+ is successfully doped into the CeO2 lattice and forms a homogeneous solid solution. Nanostructured Ce0.8Zr0.2O2 with 110.2 m2/g surface areas is produced. The proportion of chemical oxygen and surface adsorbed oxygen in the catalyst prepared from the calcination method is the highest at 23.18%. The structure may lead to charge imbalance, unsaturated bonds, and oxygen vacancies, thus increasing the adsorption of oxygen on the catalyst surface.

6.
Org Lett ; 22(13): 5135-5139, 2020 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-32610928

RESUMO

A silver-catalyzed trifluoromethoxylation of alkyl trifluoroborates with trifluoromethyl arylsulfonate as the trifluoromethoxylation reagent has been reported for the first time. This reaction is performed under mild reaction conditions and has wide functional group compatibility. In addition, the mechanism of this site-specific trifluoromethoxylation is proposed as a radical pathway.

7.
Sci Rep ; 6: 22992, 2016 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-26972164

RESUMO

Amblyseius swirskii, native to the east and southeast Mediterranean region, is a successful biological control agent of whiteflies. In this study, we investigated intraguild predations (IGP) between each stage of A. swirskii and each stage of two Phytoseiid species that occur in China, Amblyseius orientalis and Neoseiulus californicus. When there was no whitefly egg provided as the extraguild prey, IGP between A. swirskii and A. orientalis, and between A. swirskii and N. californicus, was observed in 10 and 20 out of 35 combinations, respectively. When IGP was observed, A. swirskii was the intraguild predator in 70% and 65% cases of A. orientalis and N. californicus predation, respectively. These results suggest that A. swirskii is a more aggressive intraguild predator compared to either A. orientalis or N. californicus. When whitefly eggs were provided as the extraguild prey, IGP between A. swirskii and N. californicus decreased greatly, but no significant decrease of IGP was observed between A. swirskii and A. orientalis. Amblyseius swirskii was able to complete development on both heterospecific predatory mites, and both heterospecific predatory mites completed their development on A. swirskii. Possible impacts that A. swirskii may have on local predatory mite populations in China are discussed.


Assuntos
Hemípteros/fisiologia , Ácaros/fisiologia , Controle Biológico de Vetores , Comportamento Predatório/fisiologia , Animais , China , Feminino , Larva/fisiologia , Região do Mediterrâneo , Ácaros/classificação , Óvulo/fisiologia , Especificidade da Espécie
8.
Bioresour Technol ; 169: 110-118, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25038506

RESUMO

Three species of macroalgae (Ulva lactuca, Laminaria japonica and Gelidium amansii) were converted into liquid oils via deoxy-liquefaction. The elemental analysis, FTIR and GC-MS results showed that the three liquid oils were all mainly composed of aromatics, phenols, alkanes and alkenes, other oxygen-containing compounds, and some nitrogen-containing compounds though there were some differences in terms of their types or contents due to the different constituents in the macroalgae feedstocks. The oxygen content was only 5.15-7.30% and the H/C molar ratio was up to 1.57-1.73. Accordingly, the HHV of the three oils were 42.50, 41.76 and 40.00 MJ/kg, respectively. The results suggested that U. lactuca, L. japonica and G. amansii have potential as biomass feedstock for fuel and chemicals and that deoxy-liquefaction technique may be an effective way to convert macroalgae into high-quality liquid oil.


Assuntos
Biotecnologia/métodos , Óleos/metabolismo , Alga Marinha/metabolismo , Carvão Vegetal/química , Cromatografia Gasosa-Espectrometria de Massas , Gases/análise , Temperatura Alta , Espectroscopia de Infravermelho com Transformada de Fourier
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