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1.
Nat Commun ; 12(1): 841, 2021 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-33547291

RESUMO

A new life begins with the unification of the maternal and paternal chromosomes upon fertilization. The parental chromosomes first become enclosed in two separate pronuclei near the surface of the fertilized egg. The mechanisms that then move the pronuclei inwards for their unification are only poorly understood in mammals. Here, we report two mechanisms that act in concert to unite the parental genomes in fertilized mouse eggs. The male pronucleus assembles within the fertilization cone and is rapidly moved inwards by the flattening cone. Rab11a recruits the actin nucleation factors Spire and Formin-2 into the fertilization cone, where they locally nucleate actin and further accelerate the pronucleus inwards. In parallel, a dynamic network of microtubules assembles that slowly moves the male and female pronuclei towards the cell centre in a dynein-dependent manner. Both mechanisms are partially redundant and act in concert to unite the parental pronuclei in the zygote's centre.


Assuntos
Núcleo Celular/metabolismo , Fertilização/genética , Forminas/genética , Proteínas dos Microfilamentos/genética , Proteínas do Tecido Nervoso/genética , Zigoto/metabolismo , Proteínas rab de Ligação ao GTP/genética , Actinas/genética , Actinas/metabolismo , Animais , Núcleo Celular/ultraestrutura , Feminino , Forminas/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Genes Reporter , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Proteínas dos Microfilamentos/metabolismo , Microtúbulos/metabolismo , Microtúbulos/ultraestrutura , Movimento , Proteínas do Tecido Nervoso/metabolismo , Oócitos/metabolismo , Oócitos/ultraestrutura , Espermatozoides/metabolismo , Espermatozoides/ultraestrutura , Zigoto/ultraestrutura , Proteínas rab de Ligação ao GTP/metabolismo
2.
Rev Bras Ginecol Obstet ; 43(1): 54-60, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33513637

RESUMO

Scientific information on the impact of the new coronavirus (SARS-CoV-2) on the health of pregnant women, fetuses and newborns is considered of limited confidence, lacking good-quality evidence, and drawing biased conclusions. As a matter of fact, the initial impressions that the evolution of COVID-19 was no different between pregnant and non-pregnant women, and that SARS-CoV-2 was not vertically transmitted, are confronted by the documentation of worsening of the disease during pregnancy, poor obstetric outcomes, and the possibility of vertical transmission. The present article aims to compile the data available on the association of COVID-19 and reproductive events, from conception to birth.


Assuntos
Complicações Infecciosas na Gravidez , Cuidado Pré-Natal , Parto Obstétrico , Feminino , Fertilização , Humanos , Transmissão Vertical de Doença Infecciosa , Gravidez
3.
Aquat Toxicol ; 231: 105740, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33440272

RESUMO

Ensuring that oocytes are fertilized by a single sperm during broadcast spawning is crucial for the fertilization success of many marine invertebrates. Although the adverse impacts of ocean acidification (OA) on various marine species have been revealed in recent years, its impact on polyspermy and the underlying mechanisms involved remain largely unknown. Therefore, in the present study, the effect of OA on polyspermy risk was assessed in a broadcast spawning bivalve, Tegillarca granosa. In addition, the impacts of OA on the two polyspermy blocking processes, the fast block (membrane depolarization) and the permanent block (cortical reaction), were investigated. The results show that the exposure of oocytes to two future OA scenarios (pH 7.8 and pH 7.4) leads to significant increases in polyspermy risk, about 1.70 and 2.38 times higher than the control, respectively. The maximum change in the membrane potential during oocyte membrane depolarization markedly decreased to 15.79 % (pH 7.8) and 34.06 % (pH 7.4) of the control value. Moreover, the duration of oocyte membrane depolarization was significantly reduced to approximately 63.38 % (pH 7.8) and 21.91 % (pH 7.4) of the control. In addition, cortical granule exocytosis, as well as microfilament migration, were significantly arrested by OA treatment. Exposure to future OA scenarios also led to significant reductions in the ATP and Ca2+ content of the oocytes, which may explain the hampered polyspermy blocking. Overall, the present study suggests that OA may significantly increase polyspermy risk in T. granosa by inhibiting membrane depolarization and arresting cortical granule exocytosis.


Assuntos
Ácidos/química , Bivalves/fisiologia , Grânulos Citoplasmáticos/metabolismo , Exocitose , Potenciais da Membrana/fisiologia , Oceanos e Mares , Espermatozoides/fisiologia , Citoesqueleto de Actina/efeitos dos fármacos , Citoesqueleto de Actina/metabolismo , Trifosfato de Adenosina/farmacologia , Animais , Cálcio/metabolismo , Movimento Celular/efeitos dos fármacos , Grânulos Citoplasmáticos/efeitos dos fármacos , Exocitose/efeitos dos fármacos , Feminino , Fertilização/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Masculino , Potenciais da Membrana/efeitos dos fármacos , Oócitos/efeitos dos fármacos , Oócitos/metabolismo , Poluentes Químicos da Água/toxicidade
4.
Ying Yong Sheng Tai Xue Bao ; 32(1): 191-200, 2021 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-33477227

RESUMO

Based on a long-term experiment in the Changwu Agro-ecological Experimental Station in Xianyang, Shaanxi, China, we examined the effects of fertilization and planting patterns on soil aggregate quantity, aggregate stability and total carbon and organic carbon distribution in different aggregate fractions through dry and wet sieving methods, as well as the TOC combustion method. There were ten treatments, including uncultivated (R), wheat continuous cropping (CK/W), wheat-corn rotation (L), and nitrogen fertilizer (N), phosphorus fertilizer (P), nitrogen and phosphorus fertilizer (NP), organic fertilizer (M), nitrogen and organic fertilizer (NM), phosphorus and organic fertilizer (PM), nitrogen and phosphorus and organic fertilizer (NPM) for CK/W. The results showed that fertilizer application and planting patterns affected soil aggregate distribution and stability, the contents and contribution rates of total C and organic C. Force-stable aggregate was mainly constituted by >0.25 mm aggregate (>67%), which was reduced by fertilization. Continuous cropping decreased micro-aggregate while rotation facilitated it and the effect was larger than fertilization. Water-stable aggregate was mainly comprised of micro-aggregate (<0.25 mm), the contribution of which was larger than 61%. Both fertilizer application and planting pattern reduced water-stable micro-aggregate. Fertilizer application and planting pattern decreased the percentage of aggregate destruction rate (PAD) and increased macro-aggregate (>0.25 mm, R0.25) content. Organic fertilizer significantly improved total C and organic C concentrations in all the fractions of force-stable aggregates. Continuous cropping and rotation cropping increased total C concentration in all the aggregate fractions while rotation cropping significantly decreased organic C concentration. Single N and P fertilization decreased soil total C concentration, while mixed application of N and P fertilizers, and organic fertilizer significantly increased soil total C concentration. The effect of planting patterns on soil total C was lower than that of fertilization. Both continuous cropping and rotation cropping increased soil total C. Mixed application of N and P fertilizers, and organic fertilizer signifi-cantly increased soil organic C concentration while single N and P fertilization decreased it. The effect of planting patterns on soil organic C was lower than that of fertilization, while rotation cropping did not facilitate soil organic C. Micro-aggregate was the most notable size fraction to total carbon and organic C, with the contribution being 21.2%-33.6%. Fertilization and planting pattern increased the contribution rate of micro-aggregate in soil total C. NP and NPM significantly increased the contribution rate of micro-aggregate in soil total C and soil organic C. The effect of rotation cropping was most obvious in driving the contribution rate of micro-aggregate in soil total C and soil organic C.


Assuntos
Carbono , Solo , Agricultura , Carbono/análise , China , Fazendas , Fertilização , Fertilizantes , Nitrogênio
5.
Ecotoxicol Environ Saf ; 208: 111714, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396045

RESUMO

Studies on the effects of unintentional intake of pyrethroid pesticides that are akin to actual human exposure settings are very rare. Such an exposure is primarily by consuming the food products as routine diet that contain residual levels of pyrethroids. In this study, rats were orally administered for 15 months with a mixture of pyrethroids at a dose that is one-fifth (high dose; HD) or one-twenty fifth (low dose; LD) of the residual levels commonly present in the average amount of rice and vegetables consumed by Indian population. Lipid profile, kidney and liver function were assessed. Lipid peroxidation, nitric oxide, antioxidant enzyme activities and histopathological changes were analyzed in the liver, lung, kidney, pancreas, testes, caput, cauda and prostate. The effect on the male reproductive system as a function of sperm count, enzyme activity of 3ß-HSD and 17ß-HSD and the expression profile of genes involved in spermatogenesis, steroidogenesis, genetic reprogramming and apoptosis of male gametes were evaluated. Significant increase in the relative organ weight, perturbations in the activities of antioxidant enzymes, lipid profile and liver function were observed in both LD and HD groups. Damage to the anatomical architecture was evident in all the tissues due to pyrethroid toxicity. Exposure to LD and HD of pyrethroid mixture resulted in decreased sperm count, activities of 3ß-HSD and 17ß-HSD, impaired capacitation and acrosome reaction and perturbations in the expression of genes that govern male gamete production. Results of our study indicate that exposure to pyrethroids for longer durations even at doses that are far below the residual levels present in the food consumed will result in severe damage to general physiological processes as well as reproductive function.


Assuntos
Exposição Dietética/efeitos adversos , Praguicidas/toxicidade , Piretrinas/toxicidade , Animais , Antioxidantes/metabolismo , Fertilização/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Tamanho do Órgão/efeitos dos fármacos , Resíduos de Praguicidas/toxicidade , Ratos , Espermatogênese/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Espermatozoides/metabolismo , Espermatozoides/patologia , Testículo/efeitos dos fármacos , Testículo/metabolismo , Testículo/patologia
6.
Nature ; 589(7841): 264-269, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33328630

RESUMO

During female germline development, oocytes become a highly specialized cell type and form a maternal cytoplasmic store of crucial factors. Oocyte growth is triggered at the transition from primordial to primary follicle and is accompanied by dynamic changes in gene expression1, but the gene regulatory network that controls oocyte growth remains unknown. Here we identify a set of transcription factors that are sufficient to trigger oocyte growth. By investigation of the changes in gene expression and functional screening using an in vitro mouse oocyte development system, we identified eight transcription factors, each of which was essential for the transition from primordial to primary follicle. Notably, enforced expression of these transcription factors swiftly converted pluripotent stem cells into oocyte-like cells that were competent for fertilization and subsequent cleavage. These transcription-factor-induced oocyte-like cells were formed without specification of primordial germ cells, epigenetic reprogramming or meiosis, and demonstrate that oocyte growth and lineage-specific de novo DNA methylation are separable from the preceding epigenetic reprogramming in primordial germ cells. This study identifies a core set of transcription factors for orchestrating oocyte growth, and provides an alternative source of ooplasm, which is a unique material for reproductive biology and medicine.


Assuntos
Oócitos/metabolismo , Oogênese/genética , Fatores de Transcrição/metabolismo , Animais , Linhagem da Célula , Epigênese Genética , Feminino , Fertilização , Meiose , Metilação , Camundongos , Oócitos/citologia , Folículo Ovariano/citologia , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/metabolismo
7.
Huan Jing Ke Xue ; 42(1): 394-402, 2021 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-33372492

RESUMO

Cadmium (Cd) is one of the commonly found heavy metal contaminants in soil and has a toxic effect on plants and humans. Understanding the Cd resistance of soil microorganisms under different fertilization regimes can provide a theoretical basis for controlling heavy metal pollution by organic fertilizers. In order to investigate the effects of inorganic and organic fertilizers on the Cd resistance level of soil microorganisms, paddy soil samples were taken in Changzhou, Shanggao, and Fuzhou. A functional gene array (GeoChip 5.0) was used to investigate the distribution of microbial Cd resistance genes. The results indicated that the content of available Cd in soil with organic fertilizer[(1.08±0.70) mg·kg-1] was significantly lower than that in soils with inorganic fertilizer[(3.75±1.22) mg·kg-1](P<0.05). A total of 639 Cd resistance genes were detected. The abundance of microbial Cd resistance gene in soil with organic fertilizer was higher than that of inorganic soil. The content of available Cd, moisture content, pH, and ammonium nitrogen were important environmental factors affecting the distribution of Cd resistant microorganisms. Analysis of the molecular ecological network of Cd resistant microorganisms showed that pH, moisture content, and the effective state of the Cd content were the main factors affecting the potential interaction of functional microorganisms with inorganic fertilizer, and the main factors were total potassium and moisture content with organic fertilizer. Compared with inorganic fertilizers, the application of organic fertilizers can improve the Cd resistance level of microorganisms in soil and promote positive relationships among Cd resistant soil microorganisms.


Assuntos
Poluentes do Solo , Solo , Cádmio/análise , Cádmio/toxicidade , Fertilização , Fertilizantes/análise , Humanos , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
8.
Anim Sci J ; 91(1): e13493, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33314533

RESUMO

Although successful fertilization is completed by only 150 sperm in the pig oviduct, more than 50,000 sperms are required to achieve a fertilization rate of more than 70% by pig in vitro fertilization (IVF). In this study, to improve the efficiency of pig IVF, the effects of hypoxic conditions and treatment with creatine and methyl-beta cyclodextrin (MßCD) on the glycolytic pathway were investigated. Under low O2 conditions, zig-zag motility was strongly induced within 30 min; however, the induction disappeared at 60 min. Although caffeine suppressed zig-zag motility under low O2 conditions, creatine induced and sustained zig-zag motility until 120 min. Additionally, pretreatment with MßCD for 15 min greatly enhanced zig-zag motility via ATP production in sperm incubated with creatine under low O2 conditions. Sperm pretreated with MßCD were used for IVF in medium containing creatine under low O2 conditions. A fertilization rate of approximately 70% was achieved with only 1.0 x 104 sperms/mL, and there were few polyspermic embryos. Therefore, our novel method was beneficial for efficient production of pig embryos in vitro. Moreover, the zig-zag motility may be a novel movement which boar capacitated sperm exhibit in the culture medium.


Assuntos
Anaerobiose/fisiologia , Creatina/farmacologia , Fertilização In Vitro/métodos , Fertilização In Vitro/veterinária , Fertilização/efeitos dos fármacos , Motilidade Espermática , Interações Espermatozoide-Óvulo/efeitos dos fármacos , Espermatozoides/fisiologia , Suínos/fisiologia , beta-Ciclodextrinas/farmacocinética , Animais , Sinergismo Farmacológico , Ejaculação/fisiologia , Feminino , Fertilização/fisiologia , Masculino , Interações Espermatozoide-Óvulo/fisiologia , beta-Ciclodextrinas/farmacologia
9.
Ying Yong Sheng Tai Xue Bao ; 31(9): 3060-3066, 2020 Sep 15.
Artigo em Chinês | MEDLINE | ID: mdl-33345507

RESUMO

Fertilization is an effective management to maintain and increase soil organic carbon (SOC) level in agroecosystems. Both microbial metabolism and plant component retention control SOC sequestration. Here, we used amino sugars and lignin as biomarkers to investigate the responses of distribution of microbial necromass and plant debris in a long-term cultivated soil (30 years) and SOC accumulation to different fertilization regime. The results showed that, compared with unfertilized treatment, inorganic fertilizer application (N fertilizer-only or the combination of organic or inorganic fertilizers) increased crop production and soil amino sugar accumulation, but did not affect the concentrations of lignin and SOC, indicating that inorganic fertilizer stimulated the assimilation of microbial substrate and accelerated the turnover of SOC and lignin in the plough layer. Compared with inorganic fertilizer treatment, long-term organic fertilizer application promoted SOC accumulation (38.3%), but did not affect amino sugar concentration in SOC, which indicated that soil could reach a 'saturation' state with respect to microbial residue accumulation. In contrast, the application of organic fertilizer increased the proportion of lignin in SOC,indicating that the contribution of plant residues to SOC persistence was enhanced. Compared with the manure-only treatment, organic-inorganic combined application mainly increased the contribution of amino sugar to SOC accumulation. Our findings indicated that long-term fertilization could affect SOC dynamics through modulating the accumulation processes of microbial necromass and plant debris.


Assuntos
Lignina , Solo , Agricultura , Carbono , Fertilização , Fertilizantes , Esterco , Microbiologia do Solo
10.
Zhongguo Zhong Yao Za Zhi ; 45(20): 4846-4852, 2020 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-33350255

RESUMO

The ecological planting of Chinese medicinal materials is a cultivation technology that takes into account both ecological and economic benefits, and takes scientific planting technology as a guide to achieve the goal of high quality, high yield and efficiency of Chinese medicinal materials and the sustainable and healthy development of Chinese medicinal materials planting. Among them, scientific fertilization is an important measure to realize the ecological planting of Chinese medicinal materials. In recent years, the social economy has developed rapidly. In the production of Chinese herbal medicines, a large amount of chemical fertilizers and pesticides have been gradually used to increase short-term economic benefits. The unreasonable use of chemical fertilizers and pesticides has neglected the output, quality, safety, environmental pollution and environmental protection of medicinal materials. The impact of continuous development. Therefore, from the perspective of research on cultivation of Chinese medicinal materials, this article briefly describes the role and measures of scientific fertilization in ecological planting of Chinese medicinal materials. The roles of scientific fertilization in solving soil pollution and soil quality deterioration of Chinese herbal medicine cultivation, sustainable deve-lopment of Chinese herbal medicine production, unstable production quality of Chinese herbal medicine products, and quality safety are summarized separately. It is proposed measures based on the characteristics of soil fertilization, the growth and development characteristics of Chinese medicinal materials as the core, and the industrial planting model as the carrier to promote scientific fertilization in the cultivation of Chinese medicinal materials. Finally, the development direction of scientific fertilization and ecological plan-ting of traditional Chinese medicine is prospected, in order to provide support and reference for the development of ecological planting of traditional Chinese medicine.


Assuntos
Medicamentos de Ervas Chinesas , Plantas Medicinais , Grupo com Ancestrais do Continente Asiático , China , Fertilização , Humanos , Medicina Tradicional Chinesa
11.
Ying Yong Sheng Tai Xue Bao ; 31(10): 3445-3452, 2020 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-33314834

RESUMO

Two-year field experiments were conducted in 2017-2018 to examine the effects of wheat straw returning and fertilization on soil fertility and enzyme activities, as well as the yield and qua-lity of edible sweetpoato. There were five treatments, including conventional fertilization+zero straw (CK), conventional fertilization+50% straw returning (50%S), zero fertilization+100% straw returning (100%S-F), conventional fertilization+100% straw returning (100%S), conventional fertilization+100% straw retuning+150 kg N·hm-2 (100%S+N). The treatments of straw returning and fertilization significantly increased the contents of available phosphorus (P), hydroly-zable nitrogen (N), total N, and organic matter in soils, and increased the activities of soil catalase, alkaline phosphorylase, urease, and invertase. The storage root yield, single root fresh weight and commodity potato rate were significantly increased under the treatments of straw returning and fertilization. The storage root yield was the lowest under the treatment of 50%S. After two years of straw returning, storage root yield and commodity potato rate were the highest under the treatment of 100%S. In general, the contents of starch and protein in sweetpotato were increased after two years of straw returning and fertilization, but the contents of reducing sugar and soluble sugar were decreased under 100%S and 100%S+N treatments. Our results suggested that straw returning in full quantity was better than straw returning in half quantity. The storage root yield and commodity potato rate was the highest under the combination of full quantity straw returning and conventional fertilization, with the taste of sweetpotato being changed. Thus, the amount of nitrogen fertilizer should be appropriately reduced in actual practice.


Assuntos
Ipomoea batatas , Solo , Agricultura , Fertilização , Fertilizantes , Nitrogênio/análise
12.
Zhonghua Nan Ke Xue ; 26(9): 803-806, 2020 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-33377703

RESUMO

Objective: To explore the application value of sperm-hyaluronan binding (SHB) assay in in vitro fertilization and embryo transfer (IVF-ET). METHODS: This retrospective study included 163 cases of IVF-ET performed in our hospital from January to August 2019 due to female fallopian tube abnormality-induced infertility. The men were found with normal seminal parameters at semen analysis. According to the SHB rate, we divided the patients into a normal group (n = 126) and an abnormal group (n = 37) and analyzed the general conditions and the rates of normal fertilization, cleavage, available embryos, embryo implantation and clinical pregnancy. RESULTS: Statistically significant differences were observed between the normal and abnormal groups in the rates of SHB, normal fertilization and available embryos (P < 0.01 or P < 0.05), but not in the general conditions or the rates of cleavage, embryo implantation and clinical pregnancy. CONCLUSIONS: The SHB rate is not correlated with sperm concentration or the percentages of progressively motile sperm and morphologically normal sperm. Sperm-hyaluronan binding assay helps predict the outcomes of IVF-ET and embryo quality. An SHB rate of <58.5% indicates low rates of normal fertilization and available embryos, but has no significant correlation with the rates of embryo implantation and clinical pregnancy.


Assuntos
Transferência Embrionária , Fertilização In Vitro , Ácido Hialurônico/metabolismo , Espermatozoides/metabolismo , Feminino , Fertilização , Humanos , Masculino , Gravidez , Estudos Retrospectivos
13.
Rev. SPAGESP ; 21(2): 97-110, jul.-dez. 2020. tab
Artigo em Português | LILACS, Index Psicologia - Periódicos técnico-científicos | ID: biblio-1125734

RESUMO

A literatura menciona a importância do lazer na vida em família, ressaltando as interações significativas que promove e suas contribuições ao bem-estar da família. Buscou-se compreender a vivência do lazer a partir da perspectiva do grupo familiar, descrevendo as possíveis influências da experiência do lazer na dinâmica das mesmas. Participaram três famílias, que responderam a um questionário sociodemográfico e a uma entrevista do grupo familiar, além de terem produzido registros fotográficos de momentos de lazer. Para análise das entrevistas, incluindo os relatos acerca das fotografias, utilizou-se a Análise de Conteúdo. Verificou-se que as famílias descreveram atividades e concepções de lazer diversas e que todas mencionaram os efeitos positivos que a vivência coletiva do lazer gera às suas dinâmicas, favorecendo a convivência, o diálogo e a alegria. No entanto, as limitações de tempo, dinheiro, de acesso a opções de lazer e de conciliação das demandas de gerações diferentes foram descritos como empecilhos para a vivência familiar do lazer. Conclui-se refletindo acerca das implicações dos achados para políticas públicas de lazer e para uma educação para o lazer.


The literature mentions the importance of leisure in family life, highlighting the significant interactions it promotes and its contributions to family well-being. It sought to understand the experience of leisure from the perspective of the family group, describing the possible influences of the experience of leisure on their dynamics. Three families participated, who answered a sociodemographic questionnaire and an interview of the family group, besides having produced photographic records of leisure moments. For the analysis of the interviews, including the reports about the photographs, the Content Analysis was used. It was verified that the families described various leisure activities and conceptions and that all mentioned the positive effects that the collective experience of leisure generates to their dynamics, favoring the coexistence, the dialogue, and the joy. However, the limitations of time, money, access to leisure options, and the conciliation of the demands of different generations were described as impediments to the family experience of leisure. We conclude by reflecting on the implications of the findings for leisure public policies and leisure education.


En la literatura se menciona la importancia de la recreación en la vida familiar, destacando las importantes interacciones que promueve y sus contribuciones al bienestar de la familia. Trató de comprender la experiencia de recreación desde la perspectiva del grupo familiar, describiendo las posibles influencias de la experiencia de recreación en su dinámica. Participaron tres familias que respondieron a un cuestionario sociodemográfico y a una entrevista del grupo familiar, además de haber producido registros fotográficos de los momentos de recreación. Para el análisis de las entrevistas, incluyendo los informes sobre las fotografías, se utilizó el Análisis de Contenido. Se comprobó que las familias describían diversas actividades y concepciones de recreación y que todas mencionaban los efectos positivos que la experiencia colectiva de recreación genera a sus dinámicas, favoreciendo la convivencia, el diálogo y la alegría. Sin embargo, las limitaciones de tiempo, dinero, acceso a opciones de recreación y la conciliación de las demandas en las diferentes generaciones se describieron como impedimentos para la experiencia familiar de recreación. Concluimos reflexionando sobre las implicaciones de los hallazgos para las políticas públicas de recreación y para la educación del recreación.


Assuntos
Humanos , Masculino , Feminino , Qualidade de Vida , Recreação , Família , Características da Família , Relações Familiares , Fertilização , Atividades de Lazer
14.
Nat Commun ; 11(1): 5375, 2020 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-33097736

RESUMO

Eutrophication is a widespread environmental change that usually reduces the stabilizing effect of plant diversity on productivity in local communities. Whether this effect is scale dependent remains to be elucidated. Here, we determine the relationship between plant diversity and temporal stability of productivity for 243 plant communities from 42 grasslands across the globe and quantify the effect of chronic fertilization on these relationships. Unfertilized local communities with more plant species exhibit greater asynchronous dynamics among species in response to natural environmental fluctuations, resulting in greater local stability (alpha stability). Moreover, neighborhood communities that have greater spatial variation in plant species composition within sites (higher beta diversity) have greater spatial asynchrony of productivity among communities, resulting in greater stability at the larger scale (gamma stability). Importantly, fertilization consistently weakens the contribution of plant diversity to both of these stabilizing mechanisms, thus diminishing the positive effect of biodiversity on stability at differing spatial scales. Our findings suggest that preserving grassland functional stability requires conservation of plant diversity within and among ecological communities.


Assuntos
Biota , Ecossistema , Eutrofização , Pradaria , Biodiversidade , Biomassa , Fertilização , Modelos Biológicos , Plantas
15.
Anim Sci J ; 91(1): e13467, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33043536

RESUMO

The objective of this study was to estimate genetic parameters for first calving reproductive traits and growth curve characteristics in Japanese Black cattle. The Gompertz growth function was fitted to body weight-age data to obtain the mature weight (MWT) and rate of maturing (ROM) of cows. Data of reproductive traits including the first service conception rate (CR) for heifers, age at the first calving (AFC), and gestation length for the first calving were collected. Records of 3,204 animals were used for analysis. Genetic parameters were estimated using a linear uni- and bivariate animal model. The heritability estimates were moderate (0.29 for ROM) and high (0.57 for MWT) for growth curve parameters and low (0.03-0.11) for reproductive traits. There was a negative genetic correlation between MWT and ROM (-0.26), suggesting that an animal with a faster ROM would show a lower MWT. CR was negatively correlated with MWT (-0.42) but significantly and positively correlated with ROM (0.91). There was a negative genetic correlation between AFC and MWT (-0.49). These results suggest that a heifer with a faster ROM and lower MWT would show a higher CR. Meanwhile, a heifer with a lower MWT would show a higher AFC.


Assuntos
Bovinos/crescimento & desenvolvimento , Bovinos/genética , Bovinos/fisiologia , Estudos de Associação Genética/veterinária , Característica Quantitativa Herdável , Reprodução/genética , Animais , Feminino , Fertilização/genética , Gravidez/genética
16.
Nat Commun ; 11(1): 4654, 2020 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-32943640

RESUMO

The shift from maternal to embryonic control is a critical developmental milestone in preimplantation development. Widespread transcriptomic and epigenetic remodeling facilitate this transition from terminally differentiated gametes to totipotent blastomeres, but the identity of transcription factors (TF) and genomic elements regulating embryonic genome activation (EGA) are poorly defined. The timing of EGA is species-specific, e.g., the timing of murine and human EGA differ significantly. To deepen our understanding of mammalian EGA, here we profile changes in open chromatin during bovine preimplantation development. Before EGA, open chromatin is enriched for maternal TF binding, similar to that observed in humans and mice. During EGA, homeobox factor binding becomes more prevalent and requires embryonic transcription. A cross-species comparison of open chromatin during preimplantation development reveals strong similarity in the regulatory circuitry underlying bovine and human EGA compared to mouse. Moreover, TFs associated with murine EGA are not enriched in cattle or humans, indicating that cattle may be a more informative model for human preimplantation development than mice.


Assuntos
Montagem e Desmontagem da Cromatina/fisiologia , Embrião de Mamíferos/metabolismo , Desenvolvimento Embrionário/genética , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Genoma , Animais , Blastômeros , Bovinos/embriologia , Cromatina/metabolismo , Fertilização , Humanos , Camundongos , Oócitos , Especificidade da Espécie , Fatores de Transcrição/metabolismo
18.
Obstet Gynecol ; 136(4): 782-791, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32925631

RESUMO

OBJECTIVE: To investigate whether the addition of embryo biopsy performed during preimplantation genetic testing for monogenic diseases is associated with a higher risk of obstetric and neonatal complications compared with in vitro fertilization (IVF) without preimplantation genetic testing or spontaneously conceived pregnancies. METHODS: This is a cohort study of all pregnancies conceived after preimplantation genetic testing for monogenic diseases (PGT-M group) from 2006 to 2018 at Sheba Medical Center, Israel. The control groups included patients who had conceived spontaneously (spontaneous conception group) or by IVF without preimplantation genetic testing (IVF group) and delivered at Sheba Medical Center. The obstetrics outcomes were compared among the groups. Multivariable regression modeling was performed, focusing on the relationship between preimplantation genetic testing and adverse outcomes. RESULTS: Final analysis included 345 singleton and 76 twin deliveries in the PGT-M group. The spontaneous conception group included 5,290 singleton and 92 twin deliveries. The IVF group included 422 singleton and 101 twin deliveries. Among singleton pregnancies, patients in the PGT-M group had a higher rate of hypertensive disorders (6.9%) compared with those in the spontaneous conception group (2.3%; odds ratio [OR] 3.3; 95% CI 1.9-4.8; adjusted odds ratio [aOR] 14.8; 95% CI 7.4-29.8) and the IVF group (4.7%; OR 1.5; 95% CI 0.8-2.7; aOR 5.9; 95% CI 1.9-18.2). Likewise, patients in the PGT-M group had a higher rate of small-for-gestational age neonates (12.4%) compared with those in the spontaneous conception group (3.9%; OR 3.4; 95% CI 2.4-4.9; aOR 2.3; 95% CI 1.5-3.4) and the IVF group (4.5%; OR 3; 95% CI 1.7-5.2; aOR 2.5; 95% CI 1.7-5.2). Among twin pregnancies, patients in the PGT-M group also had an increased rate of hypertensive disorders compared with those in the spontaneous conception group (4.3%; OR 4.1; 95% CI 1.2-13.3; aOR 10.9; 95% CI 2.3-50) and the IVF group (4%; OR 4.5; 95% CI 1.4-14.7; aOR 3.7; 95% CI 1.1-12.8). CONCLUSION: Pregnancies conceived after preimplantation genetic testing for monogenic disorders were associated with an increased risk of obstetric complications compared with pregnancies conceived spontaneously or by IVF without preimplantation genetic testing.


Assuntos
Biópsia , Fertilização In Vitro , Doenças Genéticas Inatas/diagnóstico , Testes Genéticos/métodos , Complicações do Trabalho de Parto , Diagnóstico Pré-Implantação , Adulto , Biópsia/métodos , Biópsia/estatística & dados numéricos , Feminino , Fertilização , Fertilização In Vitro/métodos , Fertilização In Vitro/estatística & dados numéricos , Humanos , Recém-Nascido , Israel/epidemiologia , Masculino , Complicações do Trabalho de Parto/diagnóstico , Complicações do Trabalho de Parto/epidemiologia , Gravidez , Resultado da Gravidez/epidemiologia , Diagnóstico Pré-Implantação/métodos , Diagnóstico Pré-Implantação/estatística & dados numéricos , Medição de Risco , Fatores de Risco
19.
PLoS Biol ; 18(7): e3000811, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32735558

RESUMO

One of the earliest and most prevalent barriers to successful reproduction is polyspermy, or fertilization of an egg by multiple sperm. To prevent these supernumerary fertilizations, eggs have evolved multiple mechanisms. It has recently been proposed that zinc released by mammalian eggs at fertilization may block additional sperm from entering. Here, we demonstrate that eggs from amphibia and teleost fish also release zinc. Using Xenopus laevis as a model, we document that zinc reversibly blocks fertilization. Finally, we demonstrate that extracellular zinc similarly disrupts early embryonic development in eggs from diverse phyla, including Cnidaria, Echinodermata, and Chordata. Our study reveals that a fundamental strategy protecting human eggs from fertilization by multiple sperm may have evolved more than 650 million years ago.


Assuntos
Fertilização , Oócitos/metabolismo , Zinco/metabolismo , Ambystoma mexicanum , Animais , Feminino , Hidrozoários , Masculino , Strongylocentrotus purpuratus , Xenopus laevis , Peixe-Zebra
20.
Proc Biol Sci ; 287(1932): 20201286, 2020 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-32752988

RESUMO

Spermatozoa are the most morphologically diverse cell type, leading to the widespread assumption that they evolve rapidly. However, there is no direct evidence that sperm evolve faster than other male traits. Such a test requires comparing male traits that operate in the same selective environment, ideally produced from the same tissue, yet vary in function. Here, we examine rates of phenotypic evolution in sperm morphology using two insect groups where males produce fertile and non-fertile sperm types (Drosophila species from the obscura group and a subset of Lepidoptera species), where these constraints are solved. Moreover, in Drosophila we test the relationship between rates of sperm evolution and the link with the putative selective pressures of fertilization function and postcopulatory sexual selection exerted by female reproductive organs. We find repeated evolutionary patterns across these insect groups-lengths of fertile sperm evolve faster than non-fertile sperm. In Drosophila, fertile sperm length evolved faster than body size, but at the same rate as female reproductive organ length. We also compare rates of evolution of different sperm components, showing that head length evolves faster in fertile sperm while flagellum length evolves faster in non-fertile sperm. Our study provides direct evidence that sperm length evolves more rapidly in fertile sperm, probably because of their functional role in securing male fertility and in response to selection imposed by female reproductive organs.


Assuntos
Evolução Biológica , Espermatozoides/fisiologia , Animais , Drosophila/fisiologia , Feminino , Fertilização , Masculino
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