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1.
Chinese Medical Journal ; (24): 1819-1827, 2021.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-887610

RESUMO

BACKGROUND@#Twin pregnancies continue to increase worldwide; however, the current clinical prenatal evaluation for the intrauterine growth of twins still relies on the growth standards of singletons. We attempted to establish a set of fetal biometric references for Chinese twin pregnancies, stratified by chorionicity and conception mode as spontaneously conceived monochorionic diamniotic (SC-MCDA), spontaneously conceived dichorionic diamniotic (SC-DCDA), and assisted reproductive technology dichorionic diamniotic (ART-DCDA) twins.@*METHODS@#From 2016 to 2019, the ultrasonographic fetal biometric measurements were longitudinally collected in pregnant women, including fetal weight, biparietal diameter, head circumference, abdominal circumference, femur length, and humerus length. The linear mixed models were used to test the difference of growth patterns between groups, and the growth curve of each biometric parameter was modeled by a generalized additive model for location scale and shape.@*RESULTS@#A total of 929 twin pregnant women and 2019 singleton pregnant women, met the inclusion criteria. Among twin pregnancies, 148 were SC-MCDA, 215 were SC-DCDA, and 566 were ART-DCDA twins. Overall, SC-DCDA twins grew faster than SC-MCDA twins, while slower than ART-DCDA twins (all P < 0.05), and all of the three groups showed significant differences comparing with singletons, especially during the third trimester. Hence, the customized fetal growth charts of each fetal biometric parameter were, respectively, constructed for SC-MCDA, SC-DCDA, and ART-DCDA twins.@*CONCLUSIONS@#The fetal biometric trajectories demonstrated characteristic patterns according to chorionicity and conception mode. To fill the gap, we modeled fetal biometric parameters for Chinese SC-MCDA, SC-DCDA, and ART-DCDA twin pregnancies, hoping to provide a reference for the further establishment of fetal growth reference values for Chinese twin fetuses.


Assuntos
Feminino , Humanos , Gravidez , China , Desenvolvimento Fetal , Gráficos de Crescimento , Gravidez de Gêmeos , Estudos Retrospectivos , Ultrassonografia Pré-Natal
2.
Polymers (Basel) ; 12(3)2020 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-32214014

RESUMO

The self-emulsifying acrylate-based emulsions with solid content 45 wt.% were prepared in 3.5 h by reverse iodine transfer polymerization (RITP), and the polymer molecular weight (Mn) could be 30,000 g·mol-1. The influences of methacrylic acid (MAA) amount, soft/hard monomer mass ratio, and iodine amount on polymerization and latex were investigated. A moderate amount of ionized MAA was needed to stabilize the emulsion. Glass transition temperature (Tg) was decreased with the increasing mass ratio of soft/hard monomer. A higher iodine amount resulted in lower Mn. The increased Mn after chain extension of the polymer with water-insoluble monomers in iterative one-pot method proved the living of polymer. Compared with conventional emulsion polymerization, molecular weight (Mn) could be controlled, and Mn of polymer synthesized in RITP emulsion polymerization is higher; emulsion of polyacrylate-containing hydroxyl monomer units prepared by RITP emulsifier-free radical polymerization is more stable. Good properties, such as hardness, water resistance, adhesion, and increased value of maximum tensile of films modified by reaction of polyacrylate with melamine-formaldehyde (MF) resin, indicated potential application in baking coating.

3.
Org Lett ; 21(5): 1511-1514, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30767540

RESUMO

Two highly conjugated alkaloids xylaridines A (1) and B (2) were obtained as racemates from the fungus Xylaria longipes. They were resoluted into optically pure enantiomers, respectively. Their structures were determined by extensive spectroscopic analyses, X-ray diffraction, and equivalent circulating density (ECD) calculations. Compound 1 possesses a 5/6/6/5/5 fused ring system with unique 2-azaspiro[4.4]nonane substructure. The hypothesis of biosynthesis pathways for 1 and 2 was proposed.


Assuntos
Alcaloides/química , Xylariales/química , Alcaloides/isolamento & purificação , Estrutura Molecular , Estereoisomerismo , Difração de Raios X
4.
Org Lett ; 20(24): 7758-7761, 2018 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-30499682

RESUMO

Two unique cytochalasans, curtachalasins A (1) and B (2), were purified from the endophytic fungus Xylaria curta E10 harbored in the plant Solanum tuberosum. Their structures were determined by extensive spectroscopic methods, X-ray crystallographic analysis, and electronic circular dichroism calculations. These two compounds feature an unprecedented pyrolidine/perhydroanthracene (5/6/6/6 tetracyclic skeleton) fused ring system.


Assuntos
Citocalasinas/isolamento & purificação , Xylariales/química , Cristalografia por Raios X , Citocalasinas/química , Modelos Moleculares , Estrutura Molecular , Rhabdoviridae/química , Estereoisomerismo
5.
Fitoterapia ; 128: 7-11, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29715540

RESUMO

Five vibralactone derivatives containing γ, δ, ε-lactone cores, namely vibralactones X (1), Y (2), and Z1-Z3 (3-5), together with the known vibralactone, have been isolated from cultures of the basidiomycete Boreostereum vibrans. Compounds 3-5 possessed a novel bis-γ-lactone group which was found in vibralactone derivatives for the first time. Compounds 3 and 5 exhibited moderate cytotoxicities to human cancer cell lines referring to that of cisplatin.


Assuntos
Antineoplásicos/isolamento & purificação , Basidiomycota/química , Lactonas/isolamento & purificação , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Humanos , Lactonas/farmacologia , Estrutura Molecular
6.
Food Chem ; 134(2): 964-71, 2012 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-23107714

RESUMO

The antihyperlipidaemic effects of ODP-Ia, one of the main components of Opuntia dillenii Haw. polysaccharides, were studied. Gavage administration of ODP-Ia was observed to significantly decrease serum lipid levels and to increase serum high-density lipoprotein cholesterol level in hyperlipidaemic rats. Similar suppressive patterns were also seen in hepatic total cholesterol and triglyceride levels. Moreover, the ODP-Ia administration significantly increased serum lecithin:cholesterol acyltransferase activity, increased the production of serum NO, inhibited hepatic HMG-CoA reductase activity, augmented serum and hepatic superoxide dismutase activities and decreased the serum and hepatic malondialdehyde contents in hyperlipidaemic rats. In addition, a histopathological examination revealed that ODP-Ia administration significantly suppressed inflammatory cell infiltration and the expression of VCAM-1. Together, these results indicate that ODP-Ia is a potential natural product for the treatment of hyperlipidaemia-related diseases by improving antioxidant levels, modulating the activities of enzymes involved in cholesterol metabolism, promoting the production of NO and suppressing the expression of VCAM-1, thereby suppressing lipid accumulation and inflammatory cell infiltration.


Assuntos
Hiperlipidemias/tratamento farmacológico , Hipolipemiantes/administração & dosagem , Opuntia/química , Extratos Vegetais/administração & dosagem , Polissacarídeos/administração & dosagem , Acil Coenzima A/genética , Acil Coenzima A/metabolismo , Animais , Dieta Hiperlipídica/efeitos adversos , Emulsões/efeitos adversos , Humanos , Hiperlipidemias/etiologia , Hiperlipidemias/genética , Hiperlipidemias/metabolismo , Lipídeos/sangue , Fígado/enzimologia , Masculino , Ratos , Ratos Sprague-Dawley , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Triglicerídeos/metabolismo
7.
Zhong Yao Cai ; 35(1): 98-102, 2012 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-22734420

RESUMO

OBJECTIVE: To investigate specific immune modulation of Opuntia dillenii polysaccharides (ODPs) on mice (body fluid and cells). METHODS: An immunosuppressed murine model was induced by intraperitoneal injection of cyclophosphamide (Cy, ip). The intraserous hemolysin IgM, IgG levels, the proliferation of spenocytes and the proportion of T lymphocyte subsets in peripheral blood were determined after the mice treated by ODPs. Proliferative effects of ODP-I, the main component purified from ODPs, on the lymphocytes in vitro were also studied. RESULTS: ODPs could significantly increase intraserous IgM and IgG levels, significantly enhance the proliferation of T and B lymphocytes and restore them to normal level. ODPs significantly reduced the percentage of CD4+ T lymphocytes subset, therefore significantly reduced the proportion of CD4+ and CD8+ T lymphocytes of peripheral blood from immunosuppressive mice and restored it to normal level. ODP-I significantly enhanced the natural proliferation of splenic lymphocyte and assisted the proliferation of T and B lymphocytes which induced by mitogen ConA or LPS. CONCLUSION: ODPs can enhance the specific immune function of immunosuppressed mice and the proliferation of lymphocytes in vitro.


Assuntos
Adjuvantes Imunológicos/farmacologia , Hospedeiro Imunocomprometido/efeitos dos fármacos , Linfócitos/efeitos dos fármacos , Opuntia/química , Polissacarídeos/farmacologia , Adjuvantes Imunológicos/administração & dosagem , Animais , Células Cultivadas , Ciclofosfamida/administração & dosagem , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Imunoglobulinas/biossíntese , Imunoglobulinas/sangue , Terapia de Imunossupressão , Ativação Linfocitária/efeitos dos fármacos , Linfócitos/citologia , Linfócitos/imunologia , Camundongos , Polissacarídeos/administração & dosagem , Distribuição Aleatória , Baço/efeitos dos fármacos , Baço/imunologia
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