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1.
Asian J Androl ; 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38353463

RESUMO

ABSTRACT: This study aimed to investigate the effects of male hepatitis B virus (HBV) infection on male fertility, embryonic development, and in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) outcomes. We performed a retrospective cohort study that included 3965 infertile couples who received fresh embryo transfer cycles for the first time at the Fujian Maternity and Child Health Hospital (Fuzhou, China) from January 2018 to January 2021. Infertile couples were categorized based on their HBV infection status into the HBV group (HBV-positive men and HBV-negative women) and the control group (HBV-negative couples). A 1:1 propensity score matching was performed with relatively balanced covariates. Baseline characteristics, semen parameters, laboratory outcomes, clinical outcomes, and obstetric and neonatal outcomes were compared between groups. After propensity score matching, 821 couples were included in each group. Both groups had similar semen parameters and obstetric and neonatal outcomes. The HBV group showed a significantly lower live birth rate than the control group (P < 0.05). The HBV group had a significantly higher abortion rate than the control group (P < 0.05). The rates of high-quality embryos and blastocyst formation were significantly lower in the HBV group than those in the control group (both P < 0.05). In conclusion, in couples who undergo IVF/ICSI, male HBV infection reduces the live birth rate and increases the risk of miscarriage. However, the incidence of low birth weight in women with IVF/ICSI does not increase with male HBV infection.

2.
J Exp Bot ; 62(13): 4617-25, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21642236

RESUMO

Changes in actual efficiency of PS II photochemistry, non-photochemical quenching (NPQ), content of xanthophylls and kinetics of de-epoxidation were studied in ABA-fed and non-ABA-fed leaves of rice and cabbage under NaCl stress. Salt stress induced more progressive decrease in actual efficiency of PS II photochemistry (ФPS II), higher reduction state of PS II, and a small significant increase in NPQ in NaCl-sensitive rice plants as compared with NaCl-tolerant cabbage plants, whereas exogenously supplied ABA alleviated the decrease in actual efficiency of PS II photochemistry (ФPS II), induced a lower reduction state of PS II, and caused higher capacity of NPQ in ABA-fed plants than in non-ABA-fed plants. As a result, there were higher activities of photosynthetic electron transport, higher capacity of energy dissipation, and lower cumulation of excess light in cabbage than in rice plants, and in ABA-fed leaves than in non-ABA-fed leaves. The effect of ABA was more efficient in cabbage than in rice plants. Addition of exogenous ABA resulted in enhancement of the size of the xanthophyll cycle pool, promotion of de-epoxidation of the xanthophyll cycle components, and a rise in the level of NPQ by altering the kinetics of de-epoxidation of the xanthophyll cycle. Protection from photodamage appears to be achieved by coordinated contributions by exogenous ABA and xanthophyll cycle-mediated NPQ. This variety of photoprotective mechanisms may be essential for conferring photodamage tolerance under NaCl stress.


Assuntos
Ácido Abscísico/farmacologia , Brassica/efeitos da radiação , Luz , Oryza/efeitos da radiação , Substâncias Protetoras/farmacologia , Cloreto de Sódio/toxicidade , Xantofilas/metabolismo , Ácido Abscísico/metabolismo , Brassica/efeitos dos fármacos , Brassica/metabolismo , Meia-Vida , Cinética , Oryza/efeitos dos fármacos , Oryza/metabolismo , Processos Fotoquímicos/efeitos dos fármacos , Processos Fotoquímicos/efeitos da radiação , Complexo de Proteína do Fotossistema II/metabolismo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Folhas de Planta/efeitos da radiação
3.
J Integr Plant Biol ; 51(11): 1040-9, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19903225

RESUMO

Substrate selectivity of glycerol-3-phosphate acyltransferase (EC 2. 3. 1. 15) of rice (Oryza sativa L.) was explored in a comparative study of acyltransferases from seven plant species. In vitro labeling of acyl carrier protein (ACP) with (14)C or (3)H showed that acyltransferase from chill-sensitive plants, such as rice that uses either oleic (18:1) or palmitic acid (16:0) as acyl donor at comparable rates, displays lower selectivity than the enzyme from chill-resistant plants, such as spinach, which preferentially uses oleic acid (18:1) rather than palmitic acid (16:0) as an acyl donor. This may be a result of the size and character of the substrate-binding pocket of acyltransferase. Homology modeling and protein structure-based sequence alignment of acyltransferases revealed that proteins from either chill-sensitive or chill-tolerant plants shared a highly conserved domain containing the proposed substrate-binding pocket. However, the aligned residues surrounding the substrate-binding pocket are highly heterogeneous and may have an influence mainly on the size of the substrate binding pockets of acyltransferases. The substrate selectivity of acyltransferase of rice can be improved by enlarging the substrate-binding pocket using molecular biological methods.


Assuntos
Glicerol-3-Fosfato O-Aciltransferase/metabolismo , Oryza/enzimologia , Sequência de Aminoácidos , Sítios de Ligação , Biocatálise , Sequência Conservada , Evolução Molecular , Glicerol-3-Fosfato O-Aciltransferase/química , Lisofosfolipídeos/metabolismo , Dados de Sequência Molecular , Estrutura Secundária de Proteína , Padrões de Referência , Alinhamento de Sequência , Especificidade por Substrato
4.
J Integr Plant Biol ; 50(2): 194-202, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18713442

RESUMO

In an attempt to explore the relationships between phosphatidylglycerol (PG) molecular species of thylakoid membrane lipids and sensitivities to chilling-induced photoinhibition, PG molecular species, D1 protein, electron transport activities of thylakoid membrane and the potential quantum yield (F(v)/F(m)) in rice treated under middle and low photon flux density (PFD) at 11 degrees C were analyzed by high performance liquid chromatography, enzyme hydrolysis, gas phase chromatography (GC) and so on. Results showed that the major molecular species of PGs in rice thylakoid membrane were 18:3/16:0, 18:3/16:1(3t), 18:2/16:0, 18:2/16:1(3t), 18:1/16:0, 18:1/16:1(3t), 16:0/16:0, 16:0/16:1(3t). There were large differences in the contents of unsaturated PG molecular species such as 18:1 approximately 3/16:0 approximately 16:1(3t) and saturated PG molecular species like 16:0/16:0 approximately 16:1(3t) among japonica cv 9516 (j-9516), japonica-indica hybrid F1 j-9516/i-SY63 (ji-95SY) and indica cv Shanyou 63 (i-SY63). J-9516 containing higher contents of unsaturated PG molecular species was manifest in stable D1 protein contents under chill and tolerant to chill-induced photoinhibition. In contrast to j-9516, i-SY63 with lower contents of unsaturated PG molecular species, exhibited unstable D1 protein contents under chill and was sensitive to chill-induced photoinhibition. ji-95SY containing middle contents of unsaturated PG molecular species between those of j-9516 and i-SY63, exhibited mid extent of sensitivity to chill-induced photoinhibition. The losses in D1 protein also account for the inhibition in electron transport activity of thylakoid membrane and the observed decline in F(v)/F(m). The PG molecular species that is efficient in raising chilling-resistant capacity were those containing unsaturated fatty acids, namely, unsaturated PG molecular species. These results implied that the substrate selectivity of the glycerol-3-phosphate acyltransferase in chloroplasts towards 16:0 or 18:1 displayed greatly the difference between japonica and indica rice. It was possible to enhance the capacity of resistance to chilling-induced photoinhibition by improving or modifying the GPAT gene.


Assuntos
Temperatura Baixa , Luz , Lipídeos de Membrana/metabolismo , Oryza/metabolismo , Oryza/efeitos da radiação , Fosfatidilgliceróis/metabolismo , Tilacoides/metabolismo , Transporte de Elétrons/efeitos da radiação , Ácidos Graxos Insaturados/metabolismo , Complexo de Proteína do Fotossistema II/metabolismo
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