RESUMEN
OBJECTIVES: Multiple studies have suggested that women have worse outcomes than men following mitral valve (MV) surgery-most of those studies reported on conventional sternotomy (CS) MV surgery. Therefore, we aimed to explore whether or not the minimally invasive mitral valve surgery (MIMVS) approach might mitigate a worse survival in women following MV surgery. METHODS: We identified patients with isolated primary MV operations with or without tricuspid valve repair performed between 2007 and 2019. Patients were propensity score-matched across the MIMVS and CS surgical approaches. Sex was excluded from the matching process to discern whether female patients had a different likelihood of receiving minimally invasive surgery than males. A Cox proportional hazards model was fitted in the matched cohort and adjusted for the imbalance in baseline characteristics using the propensity score. RESULTS: Of 956 patients (417 MIMVS, 539 CS; 424 females), the matched set comprised 342 pairs (684 patients; 296 females) of patients who were well balanced across MIMVS and CS groups with regard to preoperative clinical characteristics. We observed a 47/53% female/male ratio in the CS group and a 39/61% in the MIMVS group, P = 0.054. In both matched groups, women were older than males. A Cox model adjusted for propensity scores showed no survival difference with sex, surgical type or interaction. CONCLUSIONS: Women present to the surgical team at an older age. They appear less likely to be considered for a MIMVS approach than men. Neither sex nor surgical approach was associated with worse survival in a matched sample.
Asunto(s)
Insuficiencia de la Válvula Mitral , Herida Quirúrgica , Femenino , Humanos , Masculino , Válvula Mitral/cirugía , Resultado del Tratamiento , Esternotomía , Insuficiencia de la Válvula Mitral/cirugía , Procedimientos Quirúrgicos Mínimamente Invasivos , Estudios RetrospectivosRESUMEN
MAIN CONCLUSION: NO accelerates transition of germinated embryos from heterotrophy to autotrophy by stimulation of chloroplasts maturation. NO-mediated autotrophy of apple seedlings correlates to increased content of RuBisCO small subunit and improvement of parameters of chlorophyll a fluorescence. Nitric oxide (NO) acts as signaling molecule involved in regulation of various physiological processes in plants, although its involvement in cotyledons greening is poorly recognized. To identify the importance of NO signal for plant growth and development we investigated the effects of short-term application of NO at various developmental stages of seedlings of apple (Malus domestica Borkh.) on cotyledons' chlorophyll a to b ratio, chlorophyll a fluorescence, photosynthetic activity, carbohydrates and RuBisCO both subunits content. NO-dependent biochemical alterations were linked to cytological observation of developing plastids in cotyledons of apple plants. Abnormal plantlets developing from dormant apple embryos are characterized by anatomical malformations of cotyledons. Short-term pre-treatment with NO of isolated embryos or seedlings with developmental anomalies resulted in formation of plants with cotyledons of equal size and chlorophyll content; these responses were blocked by NO scavenger. NO independently of time point of application accelerated embryos transition from heterotrophy to autotrophy by stimulation of photosynthetic activity, improvement of parameters of chlorophyll a fluorescence (F v/F m, F v/F 0) and increased content of RuBisCO small subunit. Further analysis showed that NO application modified glucose and hydrogen peroxide concentration in cotyledons. Beneficial effect of NO on development of seedlings without any abnormalities was manifested at ultrastructural level by decline in amount of proplastids and induction of formation and maturation of chloroplasts. Our data suggest that progress of autotrophy of young seedlings is governed by NO acting as stimulator of chloroplast-to-nucleus signaling.
Asunto(s)
Cotiledón/metabolismo , Malus/metabolismo , Óxido Nítrico/metabolismo , Cotiledón/efectos de los fármacos , Malus/efectos de los fármacos , Óxido Nítrico/farmacología , Fotosíntesis/efectos de los fármacos , Plantones/efectos de los fármacos , Plantones/metabolismo , Semillas/efectos de los fármacos , Semillas/metabolismoRESUMEN
Deep dormancy of apple (Malus domestica Borkh.) embryos can be overcome by short-term pre-treatment with nitric oxide (NO) or hydrogen cyanide (HCN). Dormancy alleviation of embryos modulated by NO or HCN and the first step of germination depend on temporary increased production of reactive oxygen species (ROS). Direct oxidative attack on some amino acid residues or secondary reactions via reactive carbohydrates and lipids can lead to the formation of protein carbonyl derivatives. Protein carbonylation is a widely accepted covalent and irreversible modification resulting in inhibition or alteration of enzyme/protein activities. It also increases the susceptibility of proteins to proteolytic degradation. The aim of this work was to investigate protein carbonylation in germinating apple embryos, the dormancy of which was removed by pre-treatment with NO or HCN donors. It was performed using a quantitative spectrophotometric method, while patterns of carbonylated protein in embryo axes were analyzed by immunochemical techniques. The highest concentration of protein carbonyl groups was observed in dormant embryos. It declined in germinating embryos pre-treated with NO or HCN, suggesting elevated degradation of modified proteins during seedling formation. A decrease in the concentration of carbonylated proteins was accompanied by modification in proteolytic activity in germinating apple embryos. A strict correlation between the level of protein carbonyl groups and cotyledon growth and greening was detected. Moreover, direct in vitro carbonylation of BSA treated with NO or HCN donors was analyzed, showing action of both signaling molecules as protein oxidation agents.
Asunto(s)
Cianuro de Hidrógeno/farmacología , Malus/fisiología , Óxido Nítrico/farmacología , Especies Reactivas de Oxígeno/metabolismo , Cotiledón/efectos de los fármacos , Cotiledón/embriología , Cotiledón/fisiología , Germinación , Peróxido de Hidrógeno/metabolismo , Malus/efectos de los fármacos , Malus/embriología , Oxidación-Reducción , Latencia en las Plantas , Proteínas de Plantas/metabolismo , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/embriología , Raíces de Plantas/fisiología , Carbonilación Proteica , Plantones/efectos de los fármacos , Plantones/embriología , Plantones/fisiología , Semillas/efectos de los fármacos , Semillas/embriología , Semillas/fisiologíaRESUMEN
Reactive oxygen (ROS) and nitrogen (RNS) species play a signaling role in seed dormancy alleviation and germination. Their action may be described by the oxidative/nitrosative "window/door". ROS accumulation in embryos could lead to oxidative modification of protein through carbonylation. Mature apple (Malus domestica Borkh.) seeds are dormant and do not germinate. Their dormancy may be overcome by 70-90 days long cold stratification. The aim of this work was to analyze the relationship between germinability of embryos isolated from cold (5°C) or warm (25°C) stratified apple seeds and ROS or nitric oxide (NO) production and accumulation of protein carbonyl groups. A biphasic pattern of variation in H2O2 concentration in the embryos during cold stratification was detected. H2O2 content increased markedly after 7 days of seeds imbibition at 5°C. After an additional two months of cold stratification, the H2O2 concentration in embryos reached the maximum. NO production by the embryos was low during entire period of stratification, but increased significantly in germination sensu stricto (i.e. phase II of the germination process). The highest content of protein carbonyl groups was detected after 6 weeks of cold stratification treatment. Fluctuation of H2O2 and protein carbonylation seems to play a pivotal role in seed dormancy alleviation by cold stratification, while NO appears to be necessary for seed germination.
Asunto(s)
Frío , Peróxido de Hidrógeno/metabolismo , Malus/crecimiento & desarrollo , Óxido Nítrico/metabolismo , Latencia en las Plantas , Carbonilación Proteica , Semillas/crecimiento & desarrollo , Malus/metabolismo , Plantones/crecimiento & desarrollo , Plantones/metabolismo , Semillas/metabolismo , SolubilidadRESUMEN
Plant cells produce reactive oxygen species (ROS) continuously as a byproducts of oxygen metabolism and reaction to various environmental stresses. ROS are considered as chemicals inducing damage of cellular components (DNA, lipids and proteins), but also might act as signaling agents. Protein oxidation is one of covalent modification of protein induced by ROS or other products of oxidative stress. Carbonylation of particular amino acid residues (arginine, lysine, treonine or proline) is one of the most commonly occurring oxidative modification of proteins. This modification might lead to alteration in protein activity, its proteolytic breakdown or, in the opposite, aggregate formation. Carbonylated proteins have been identified in many plant species at different stage of growth and development. The analysis of subcellular localization of carbonylated proteins arised the hypothesis on their signaling function. We summarize the current knowledge on the detection of carbonylation protein in plants taking to the account the conditions which may influence their production or removal. We present also their putative role in plant physiology and discuss interaction between ROS and RNS in regulation of protein carbonylation.
Asunto(s)
Fenómenos Fisiológicos de las Plantas/fisiología , Carbonilación Proteica/fisiología , Aminoácidos/metabolismo , Óxido Nítrico/metabolismo , Especies Reactivas de Oxígeno/metabolismoRESUMEN
Deep dormancy of apple (Malus domestica Borkh.) seeds is terminated by a 3-month-long cold stratification. It is expressed by rapid germination of seeds and undisturbed growth of seedlings. However, stimulation of germination of isolated apple embryos is also observed after applying inhibitors of cytochrome c oxidase: nitric oxide (NO) or hydrogen cyanide (HCN) during the first 3-6 h of imbibition of dormant embryos. The aim of this work was to compare the effect of yet another toxic gaseous molecule carbon monoxide (CO) with the effects of HCN and NO on germination of apple embryos and growth and development of young seedlings. We demonstrated that stimulation of germination after short-term pre-treatment with HCN, NO or CO was accompanied by enhanced NO emission from the embryo axes during their elongation. Moreover, similarly high NO production from non-dormant embryos, after cold stratification, was detected. Therefore, we propose that NO may act as signaling molecule in apple embryo dormancy break.