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1.
Ciênc. rural (Online) ; 52(3): e20201079, 2022. ilus, tab, graf
Article in English | LILACS-Express | LILACSEXPRESS, LILACS, VETINDEX | ID: biblio-1339668

ABSTRACT

Andropogon lateralis Nees is a native grass of southern Brazil and is one of the most frequent specie found in native grasslands. The species is widely distributed and has a high degree of phenotypic plasticity, which makes it highly adaptable to different edaphoclimatic conditions and management. This study aimed to evaluate the behavior of twelve ecotypes of A. lateralis, collected in different regions of the state of Rio Grande do Sul and cut to three different heights and subjected to two different defoliation frequencies. From September to February, the ecotypes were evaluated for total dry matter, leaf and stem yields. In addition, total, vegetative and reproductive tillers and plant height were measured. These characteristics are important for the selection of superior genotypes in terms of genetic variability and forage production. Total dry matter and leaf dry matter are characteristics with agronomic importance and they showed the highest correlation (r = 0.77), enabling an indirect selection for one of these characteristics. The natural selection of plants resulted in distinct structural, morphological and productive characteristics with heterogeneity that allows the selection and grouping according to the characteristics, ecotypes with superior agronomic characteristics can be included in breeding programs.


Andropogon lateralis Nees é uma gramínea nativa do sul do Brasil e uma das espécies mais frequentes na flora dos campos nativos da região. Possui ampla distribuição e alto grau de plasticidade fenotípica, tornando-o adaptável as condições edafoclimáticas e a práticas de desfolha. Este estudo teve como objetivo avaliar a dissimilaridade entre doze ecótipos de A. lateralis N., coletados em diferentes regiões do Rio Grande do Sul, submetidos a duas frequências de desfolha e três alturas de corte. No período de setembro a fevereiro, os ecótipos foram avaliados quanto à produção de matéria seca total, de lâminas foliares e de colmo. Além disso, foram medidos o número de perfilhos totais, vegetativos e reprodutivos e a altura das plantas. Essas características são importantes para a seleção de genótipos superiores em termos de variabilidade genética e produção de forragem. A matéria seca total e a matéria seca foliar são características com importância agronômica e apresentaram a maior correlação (r = 0,77), possibilitando uma seleção indireta para uma dessas características. A seleção natural das plantas resultou em características estruturais, morfológicas e produtivas distintas com uma heterogeneidade que permite a seleção e agrupamento de acordo com as características, ecótipos com características agronômicas superiores podem ser incluídos em programas de melhoramento.


Subject(s)
Selection, Genetic , Andropogon/growth & development , Andropogon/genetics , Ecotype
2.
Psicol. USP ; 32: e200003, 2021. tab
Article in Portuguese | LILACS, INDEXPSI | ID: biblio-1287649

ABSTRACT

Resumo A depressão tem alcançado níveis epidêmicos ao redor do mundo. Seria a depressão um distúrbio mental, como é consenso na saúde mental? Teóricos evolucionistas têm-se questionado quanto à função da depressão e proposto modelos específicos para explicá-la. O objetivo deste artigo é apresentar teorias evolucionistas da depressão, discutir as relações de complementariedade e contraposição entre elas e as implicações sociais e práticas para o tratamento da depressão. Essas reflexões e questionamentos no domínio da saúde mental podem influenciar novos estudos a partir de uma perspectiva não patológica da depressão. No âmbito da psicologia essa perspectiva fornece subsídios para repensar a psicoterapia com o deprimido, enfocando a análise causal e a resolução de problemas. Sugere-se a realização de estudos empíricos com a finalidade de testar e sistematizar as teorias evolucionistas da depressão.


Resumen La depresión ha alcanzado niveles epidemiológicos alrededor del mundo. ¿Será la depresión un trastorno mental como se cree en el dominio de la salud mental? Teóricos evolucionistas se cuestionan sobre la depresión y han propuesto modelos específicos para explicarla. El objetivo de este artículo fue presentar teorías evolutivas de la depresión, discutir las relaciones de complementariedad y contraposición entre ellas, así como las implicaciones sociales y prácticas para su tratamiento. Estas reflexiones y cuestionamientos, en el dominio de la salud mental, pueden influir en nuevos estudios a partir de una perspectiva no patológica de la depresión. En el ámbito de la psicología, esta perspectiva provee subsidios para repensar la psicoterapia con el deprimido enfocándose en el análisis causal y la resolución de problemas. Se sugiere la realización de estudios empíricos con la finalidad de probar y sistematizar las teorías evolucionistas de la depresión.


Résumé La dépression a atteint les proportions d'une épidémie mondiale. Les théoriciens évolutionnistes se sont interrogés sur la fonction de la dépression et ont proposé des modèles spécifiques pour l'expliquer. Cet article vise à présenter les différentes théories évolutionnistes de la dépression, discuter leurs relations de complémentarité et d'opposition, et débattre les possibles implications sociales et pratiques pour le traitement de la dépression. Ces réflexions dans le domaine de la santé mentale peuvent influencer de nouvelles études dans une perspective non pathologique de la dépression. Dans le domaine de la psychologie, cette perspective permet de repenser la psychothérapie avec les personnes déprimées, en se concentrant sur l'analyse causale et la résolution des problèmes. Des études empiriques sont proposées dans le but de tester et systématiser les théories évolutionnistes de la dépression.


Abstract Depression has reached epidemic levels worldwide. Would that be a mental disorder, as claimed by consensus on mental health? Evolutionary theorists have questioned the function of depression and proposed specific models to explain it. The aim of this paper is to present the evolutionary theories of depression, to discuss the complementarity and contradictions between these theories, and to present the social and practical implications for the treatment of depression. Those reflections and issues in the field of mental health may influence further studies from a non-pathological perspective of depression. In the field of psychology, this perspective provides insights to reevaluate psychotherapy to treat depression by focusing on causal analysis and problem solving. The study suggests that new empirical studies should be conducted to test and systematize evolutionary theories of depression.


Subject(s)
Selection, Genetic , Cost of Illness , Depression/etiology , Depression/psychology , Mental Health , Adaptation
3.
Hist. ciênc. saúde-Manguinhos ; 27(4): 1055-1075, Oct.-Dec. 2020.
Article in Portuguese | LILACS | ID: biblio-1142991

ABSTRACT

Resumo O artigo analisa as narrativas de viagem ao interior de Mato Grosso e Goiás publicadas em 1935 e 1936 pelo explorador paulista Hermano Ribeiro da Silva, que obtiveram considerável sucesso editorial e impacto no meio letrado brasileiro. Concentramo-nos em suas ideias sobre a relação entre o ambiente do Brasil Central e o homem sertanejo, sobre as potencialidades de exploração econômica da região e sobre o papel do Estado na condução de iniciativas capazes de promover sua incorporação efetiva à nacionalidade. Buscamos também compreender a fundamentação de seu discurso em conceitos e esquemas científicos genéricos dotados de poder retórico e argumentativo.


Abstract The article analyzes the travel narratives to the hinterlands of the states of Mato Grosso and Goiás published in 1935 and 1936 by the São Paulo-based explorer Hermano Ribeiro da Silva, which proved a great publishing success and had a considerable impact on lettered society in Brazil. The analysis focuses on his ideas about the relationship between the environment in Central Brazil and the man who inhabited it, the potential economic exploitation of the region, and the role of the State in orchestrating initiatives capable of promoting its effective incorporation into the nationhood. It also seeks to understand how he grounded his discourse on generic scientific concepts and schemas endowed with rhetorical and argumentative power.


Subject(s)
Humans , History, 20th Century , Travel/history , Indians, South American/history , Environment , Portugal/ethnology , Selection, Genetic , Brazil , Ecosystem , Colonialism/history , Federal Government/history , European Continental Ancestry Group/history , Famous Persons , Indigenous Peoples/history , Acclimatization
4.
Arq. bras. med. vet. zootec. (Online) ; 72(4): 1479-1486, July-Aug. 2020. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1131519

ABSTRACT

The aim of this study was to estimate genetic parameters and genetic trends for reproductive traits in Wistar rats. A total of 1,167 data records from 283 females over six generations of monogamous mating pairs was used. Heritability and genetic correlation were estimated through Bayesian inference and genetic trends were calculated by linear regression of breeding values over generations. Heritability estimates for litter size at birth (LS), calving interval (CI), pup mortality (PM) and maternal cannibalism (CAN) presented low magnitude, ranging from 0.01 to 0.13. CAN presented high and positive genetic correlation with LS and PM (0.77 and 0.78, respectively). On the other hand, all the other estimated genetic correlations were not significant. Genetic trend was positive for LS (+0.0900 pups per generation), and negative for PM and CAN (-1.0085 and -0.5217 pups per generation, respectively). For CI the genetic trend was not significant. It is recommended to increase selection intensity on dams in this Wistar rat population in order to accelerate the genetic progress.(AU)


O objetivo deste estudo foi estimar os parâmetros genéticos e as tendências genéticas de características reprodutivas em ratos Wistar. Foram analisados 1.167 registros coletados em 283 fêmeas ao longo de seis gerações de pares de acasalamentos monogâmicos. Herdabilidade e correlação genética foram estimadas por meio de inferência bayesiana, e as tendências genéticas foram calculadas pela regressão linear dos valores genéticos em função das gerações. As estimativas de herdabilidades para as características número de filhotes nascidos (LS), intervalo de parto (CI), mortalidade de filhotes (PM) e canibalismo materno (CAN) foram de baixa magnitude (0,01 a 0,13). CAN apresentou correlação genética alta e positiva com LS e PM, 0,77 e 0,78, respectivamente. As demais correlações genéticas estimadas foram não significativas. A tendência genética foi positiva para LS (+0,0900 filhote por geração) e negativa para PM e CAN (-1,0085 e -0,5217 filhote por geração, respectivamente). A tendência genética não foi significativa para CI. Recomenda-se aumentar a intensidade de seleção nas fêmeas nessa população de ratos Wistar, a,fim de acelerar o progresso genético.(AU)


Subject(s)
Animals , Female , Rats , Selection, Genetic , Rats, Wistar , Heredity , Bayes Theorem , Litter Size
5.
Fractal rev. psicol ; 32(2): 111-119, maio-ago. 2020. tab
Article in Portuguese | LILACS, INDEXPSI | ID: biblio-1133939

ABSTRACT

Este trabalho problematiza os pressupostos ontológicos assumidos no debate bioético sobre a seleção e edição do genoma humano. Com vistas ao manejo de desordens genéticas, diferentes terapêuticas têm sido empregadas clínica e experimentalmente, desde a década de 1990. Entre as estratégias de tratamento destacam-se a seleção de embriões (mediante diagnóstico genético pré-implantação) e a terapia gênica (mediante edição genética). O desenvolvimento destas técnicas suscita discussões acerca de suas implicações éticas. O presente artigo postula que distintas concepções de humanidade podem ser identificadas nas discussões, as quais fundamentam posicionamentos acerca de intervenções sobre o genoma da espécie. O artigo busca analisar essas concepções, percorrendo três passos. Primeiramente, apresenta-se o contexto biomédico de aplicação da seleção e edição do genoma humano. Em seguida, são evidenciadas discussões sobre os aspectos éticos de tais intervenções. Por fim, explicitam-se diferentes concepções de humanidade que fundamentam as referidas discussões, de maneira a problematizá-las, tendo em vista a noção de justiça distributiva.(AU)


This study discusses the ontological assumptions assumed in the bioethical debate about human genetic selection and gene editing. With a view to managing genetic disorders, different therapies have been employed clinically and experimentally, since the 1990s. Among the treatment strategies, we find embryo selection (by means of pre-implantation genetic diagnosis) and gene therapy (by means of gene editing). The development of these techniques raises discussions about their ethical implications. This article postulates that different conceptions of humanity can be identified in these discussions, grounding ethical positions regarding genome interventions. The article seeks to analyze these conceptions, following three steps. First, the biomedical context of genetic selection and gene editing is presented. Then, discussions on the ethical aspects of these interventions are highlighted. Finally, different conceptions of humanity grounding these discussions are identified and analyzed, considering the notion of distributive justice.(AU)


Subject(s)
Humans , Selection, Genetic , Genome, Human , Bioethical Issues
6.
Arq. bras. med. vet. zootec. (Online) ; 72(3): 955-960, May-June, 2020. tab
Article in English | LILACS, VETINDEX | ID: biblio-1129664

ABSTRACT

Body weight records of 231,416 Nellore females obtained from the Brazilian Association of Zebu Breeders were used to determine a linear combination between visual appraisal scores (body structure, precocity and muscling) using principal components analysis (PC), and to verify their genetic association with body weight at 12 months (BW) and age at first calving (AFC). The mixed linear model included the fixed effect of the contemporary group and the linear and quadratic effects of age at calving, random effects of genetic additive, maternal environment and temporary environment. Heritability estimates for BW, PC and AFC were 0.51, 0.30 and 0.17, respectively. Genetic additive correlations between BW and PC; BW and AFC, and PC and AFC were 0.48; -0.31 and -0.55; respectively. Spearman's correlations for the best-ranked bulls based on PC prediction were positive between BW and PC and negative among the other combinations. Heritability estimates and correlations indicate potential genetic gains for BW and CP with reduced AFC in cows. The use of PC allows positive responses on precocity and body weight development.(AU)


Utilizaram-se registros de pesos corporais de 231.416 fêmeas bovinas da raça Nelore, oriundos dos registros da Associação Brasileira de Criadores de Zebu-ABCZ, com o objetivo de estabelecer, por componentes principais, uma combinação linear (CP) das características de escores visuais de estrutura (E), precocidade (P) e musculosidade (M), bem como verificar sua associação genética com o peso corporal aos 12 meses (PC) e à idade ao primeiro parto (IPP). O modelo linear misto utilizado incluiu os efeitos fixos de grupo de contemporâneos e os efeitos linear e quadrático da idade da vaca ao parto, os efeitos aleatórios genético aditivo, ambiente materno e ambiente temporário. Estimativas de herdabilidade para PC, CP e IPP foram iguais a 0,51; 0,30 e 0,17, respectivamente. Correlações genéticas aditivas entre PC e CP; PC e IPP; e, ainda, CP e IPP foram iguais a 0,48; -0,31 e -0,55, respectivamente. As correlações de Spearman para os melhores reprodutores classificados em relação à predição de CP foram positivas entre PC e CP e negativas entre as demais combinações. Estimativas de herdabilidade e de correlações indicam possibilidade de ganhos genéticos expressivos para PC e CP com redução para IPP nas fêmeas. A utilização de CP possibilita respostas favoráveis para precocidade sexual e desenvolvimento ponderal.(AU)


Subject(s)
Animals , Female , Cattle , Selection, Genetic , Body Weight , Body Weights and Measures/veterinary , Heredity , Parturition
8.
Arq. bras. med. vet. zootec. (Online) ; 72(1): 33-39, Jan.-Feb. 2020. graf
Article in Portuguese | LILACS, VETINDEX | ID: biblio-1088915

ABSTRACT

A biópsia embrionária associada à genotipagem permite a obtenção de informações genômicas antes mesmo da transferência dos embriões. Neste estudo, foram avaliadas amostras biopsiadas de blastocistos bovinos transferidos para receptoras (n=47), sob a hipótese de que a raça (Gir ou Girolando), o estádio embrionário (blastocisto ou blastocisto expandido) e a competência para estabelecimento de prenhez (positiva ou negativa) afetariam a quantidade e a qualidade do DNA da amostra obtida. O DNA foi extraído, amplificado, quantificado por eletroferograma e genotipado. O parâmetro call rate (CR) foi adotado para mensurar a qualidade da genotipagem. Obteve-se concentração de DNA de 86,07±171,66ng/µL e CR 0,73±0,17. O CR não variou em função da quantidade de DNA nas amostras. As variáveis raça e estádio embrionário não influenciaram a concentração de DNA, nem o CR. Houve efeito da prenhez sobre o CR (P=0,0187), mas, como houve maior CR nas amostras provenientes do grupo prenhez negativa, não foi possível associar esse parâmetro à qualidade embrionária. Concluiu-se que a raça e a qualidade embrionária não afetam os parâmetros aqui estudados em amostras embrionárias, ou seja, embriões com maiores chances de implantação não refletem alta qualidade nas amostras de biópsia genotipadas.(AU)


Embryo biopsy associated with genotyping allows genomic information before embryo transfer. In this study, blastocyst biopsy samples from embryos transferred to recipients (n= 47) were evaluated, under the hypothesis that breed (Gyr or Girolando), embryonic stage (blastocyst or expanded blastocyst) and competence to establish pregnancy (positive or negative) would affect the quantity and DNA quality of samples. DNA was extracted, amplified, quantified by electropherogram and genotyped. The parameter call rate (CR) was used to measure the quality of genotyping. DNA concentration of 86.07±171.66ng/µl, and CR 0.73±0.17 was obtained. CR did not vary according to the amount of DNA in the samples. The variables breed and embryonic stage had no influence on DNA concentration or CR. There was pregnancy effect on the CR (P= 0.0187), but since there was a higher CR in the samples from the negative pregnancy group, it was not possible to associate this parameter with the embryonic quality. We conclude that the breed and embryo quality do not affect the evaluated parameters in embryonic samples. Embryos with higher chances of implantation do not reflect high quality in embryo biopsy genotyped samples.(AU)


Subject(s)
Animals , Cattle , Selection, Genetic , Biopsy/veterinary , Sequence Analysis, DNA/veterinary , Embryo, Mammalian , Genotyping Techniques/veterinary , In Vitro Techniques/veterinary
9.
Neotrop. ichthyol ; 18(2): e190093, 2020. tab, graf
Article in English | LILACS | ID: biblio-1135375

ABSTRACT

Several organisms match their skin color to the prevalent background color, granting crypsis against predators. The rate at which body color changes occur varies among organisms as a result of physiological constraints and adaptation to variation in contrasts between objects and the environmental background. Faster darkening of body color is favored in environments that show higher amounts of contrast between common objects and the prevailing background. Soil types in Amazon forest streams (igarapés) create distinct environments with respect to the amount of contrast, a result of the amount of sand and clay, which offers different contrasts against dead leaves. Here, we investigated differences in the rates of color change among populations of the sailfin tetra (Crenuchus spilurus) that represent lineages that live in regions of different soil types. Populations inserted into blackwaters (sandy soil) showed higher rates of color darkening in response to exposure to a dark environment composed by dead leaves. We propose that natural selection stemming from predation can favor faster color change rate in environments where there is higher variability of contrasts between leaf litter and soil, which is common in most blackwater streams.(AU)


Diversos organismos combinam sua coloração corporal com a cor de fundo predominante no ambiente, conferindo cripticidade contra predadores. A taxa na qual as mudanças de coloração corpórea ocorrem varia entre os organismos como resultado de restrições fisiológicas e adaptação à variação de contrastes entre objetos e o ambiente. O escurecimento mais rápido da cor do corpo é favorecido em ambientes que mostram maiores quantidades de contraste entre objetos comuns e o fundo predominante. Tipos de solo em igarapés da floresta amazônica criam ambientes distintos em relação à quantidade de contraste, resultado da quantidade de areia e argila, que oferece diferentes contrastes contra folhiço submerso. Nós investigamos as diferenças nas taxas de mudança de cor entre populações do tetra-colibri Crenuchus spilurus que representam linhagens que vivem em regiões de diferentes tipos de solo. Populações inseridas em águas pretas (solo arenoso) apresentaram maiores taxas de escurecimento da cor em resposta à exposição ao ambiente escuro de folhiço submerso. Nós propomos que a seleção natural decorrente da predação pode favorecer uma taxa de mudança de cor mais rápida em ambientes onde há maior variabilidade de contrastes entre o folhiço submerso e o solo, o que é comum na maioria dos igarapés de águas pretas.(AU)


Subject(s)
Animals , Selection, Genetic , Soil , Adaptation , Characidae/growth & development , Characidae/physiology
10.
Salud colect ; 16: e2615, 2020.
Article in Spanish | LILACS | ID: biblio-1101900

ABSTRACT

RESUMEN El objetivo de este texto es analizar la posibilidad futura de que el modelo médico hegemónico siga perpetuándose o se generen cambios significativos. Para ello, se parte de las características y funciones actuales del modelo médico hegemónico y se las observa a través de algunos de los aportes de la inteligencia artificial, de las investigaciones genéticas y de la robótica, referidas a procesos de salud-enfermedad-atención-prevención, entre los que se analizan las posibilidades de fuertes incrementos en la esperanza de vida, las necesidades de "curar la senectud", así como los procesos que están modificando la relación médico-paciente, llegando a la conclusión de que si bien se observan algunas modificaciones sustantivas, las características y funciones del modelo médico hegemónico siguen siendo las mismas.


ABSTRACT The purpose of this article is to analyze the possibilities that the hegemonic medical model will continue to prevail in the future or if significant changes will take place. The discussion will take as a starting point the characteristics and current functions of the hegemonic medical model, and reexamine them through a look at advancements in artificial intelligence, genetic research, and robotics in health-illness-care-prevention processes. The analysis takes on issues such as possible increases in life expectancy, what is needed to "cure old age," as well as processes that are modifying the doctor-patient relationship. It is concluded that although significant changes are taking place, the characteristics and functions of the hegemonic medical model remain unmoved.


Subject(s)
Humans , Medicine/trends , Physician-Patient Relations , Selection, Genetic , Robotics , Aging/physiology , Artificial Intelligence , Life Expectancy , Sexuality , Reconstructive Surgical Procedures/trends , Delivery of Health Care , Genetic Research , Forecasting , Longevity
11.
Electron. j. biotechnol ; 37: 11-17, Jan. 2019. tab, ilus
Article in English | LILACS | ID: biblio-1049063

ABSTRACT

BACKGROUND: Wheat is one of the most important crops cultivated all over the world. New high-yielding cultivars that are more resistant to fungal diseases have been permanently developed. The present study aimed at the possibility of accelerating the process of breeding new cultivars, resistant to eyespot, by using doubled haploids (DH) system supported by marker-assisted selection. RESULTS: Two highly resistant breeding lines (KBP 0916 and KBH 4942/05) carrying Pch1 gene were crossed with the elite wheat genotypes. Hybrid plants of early generations were analyzed using endopeptidase EpD1 and two SSR markers linked to the Pch1 locus. Selected homozygous and heterozygous genotypes for the Pch1-linked EpD1b allele were used to produce haploid plants. Molecular analyses were performed on haploids to identify plants possessing Pch1 gene. Chromosome doubling was performed only on haploid plants with Pch1 gene. Finally, 65 DH lines carrying eyespot resistance gene Pch1 and 30 lines without this gene were chosen for the eyespot resistance phenotyping in a field experiment. CONCLUSIONS: Results of the experiment confirmed higher resistance to eyespot of the genotypes with Pch1 in comparison to those without this gene. This indicates the efficiency of selection at the haploid level.


Subject(s)
Selection, Genetic , Triticum/genetics , Triticum/metabolism , Haploidy , Plant Diseases , Breeding/methods , Gene Expression , Microsatellite Repeats , Genotype
12.
Arq. bras. med. vet. zootec. (Online) ; 71(5): 1695-1702, set.-out. 2019. tab
Article in Portuguese | LILACS, VETINDEX | ID: biblio-1038648

ABSTRACT

Utilizaram-se registros de pesos corporais padronizados aos 120, 210, 365 e 450 dias de idade, provenientes de 30.481 animais da raça Nelore, progênies de 211 reprodutores acasalados com 19.229 matrizes, oriundos de rebanhos dos estados de Mato Grosso, Mato Grosso do Sul e Goiás, com o objetivo de avaliar a presença de interação genótipo x ambiente entre os estados. As estimativas de herdabilidade entre os estados variaram de 0,09 a 0,14; 0,11 a 0,17; 0,16 a 0,27 e 0,17 a 0,35, respectivamente, para os pesos 120, 210, 365 e 450 dias de idade. As estimativas de correlação genética aditiva entre a mesma característica para os diferentes estados apresentaram valores inferiores a 0,80. As correlações de Spearman entre os valores genéticos para os pesos corporais se reduziram à medida que se aumentou a intensidade de seleção sobre os reprodutores. A presença de interação genótipo x ambiente causa maior impacto sobre a avaliação genética dos reprodutores sob intensidade de seleção elevada, sendo interessante sua consideração no processo de avaliação genética. Estimativas de tendências genéticas para todos os pesos corporais apresentaram-se crescentes ao longo dos anos nos três estados.(AU)


Data of adjusted alive weights at 120, 210, 365 and 450 days of age of 30,481 records of animals of the Nellore beef cattle breed from herds of states of Mato Grosso, Mato Grosso do Sul, and Goiás were used to study the influence of environment genotype interaction on genetic evaluation of sires. Estimates of heritability between the states ranged from 0.09 to 0.14; 0.11 to 0.17; 0.16 to 0.27 and 0.17 to 0.35, respectively for live weights 120, 210, 365 and 450 days of age. The estimates of additive genetic correlation between the same characteristic for the different states presented values lower than 0.80. Spearman correlations between breeding values obtained from live weights of sires lowered as the intensity of selection on sires increased. The presence of environment genotype interaction has greater impact on the genetic evaluation of breeding under high intensity of selection, being an interesting consideration in the process of genetic evaluation. Estimates of genetic trends for all body weights have been increasing over the years in all three states.(AU)


Subject(s)
Animals , Cattle , Selection, Genetic , Cattle/growth & development , Cattle/genetics , Environment , Genotype , Animal Husbandry/statistics & numerical data
13.
Electron. j. biotechnol ; 41: 88-94, sept. 2019. tab, ilus, graf
Article in English | LILACS | ID: biblio-1087247

ABSTRACT

Background: In industrial yeasts, selection and breeding for resistance to multiple stresses is a focus of current research. The objective of this study was to investigate the tolerance to multiple stresses of Saccharomyces cerevisiae obtained through an adaptive laboratory evolution strategy involving a repeated liquid nitrogen freeze­thaw process coupled with multi-stress shock selection. We also assessed the related resistance mechanisms and very high-gravity (VHG) bioethanol production of this strain. Results: Elite S. cerevisiae strain YF10-5, exhibiting improved VHG fermentation capacity and stress resistance to osmotic pressure and ethanol, was isolated following ten consecutive rounds of liquid nitrogen freeze­thaw treatment followed by plate screening under osmotic and ethanol stress. The ethanol yield of YF10-5 was 16% higher than that of the parent strain during 35% (w/v) glucose fermentation. Furthermore, there was upregulation of three genes (HSP26, HSP30, and HSP104) encoding heat-shock proteins involved in the stress response, one gene (TPS1) involved in the synthesis of trehalose, and three genes (ADH1, HXK1, and PFK1) involved in ethanol metabolism and intracellular trehalose accumulation in YF10-5 yeast cells, indicating increased stress tolerance and fermentative capacity. YF10-5 also showed excellent fermentation performance during the simultaneous saccharification and fermentation of VHG sweet potato mash, producing 13.40% (w/ v) ethanol, which corresponded to 93.95% of the theoretical ethanol yield. Conclusions: A multiple-stress-tolerant yeast clone was obtained using adaptive evolution by a freeze­thaw method coupled with stress shock selection. The selected robust yeast strain exhibits potential for bioethanol production through VHG fermentation.


Subject(s)
Saccharomyces cerevisiae/physiology , Ethanol/chemical synthesis , Saccharomyces cerevisiae/genetics , Selection, Genetic , Stress, Physiological , Trehalose , Yeasts , Breeding , Adaptation, Physiological , Hypergravity , Fermentation , Real-Time Polymerase Chain Reaction , Freezing , Heat-Shock Proteins
14.
Article in Korean | WPRIM | ID: wpr-759905

ABSTRACT

The nineteenth century neuroscience studied the instinct of animal to understand the human mind. In particular, it has been found that the inheritance of unconscious behavior like instinct is mediated through ganglion chains, such as the spinal cord or sympathetic nervous system, which control unconscious reflexes. At the same time, the theory of Inheritance of Acquired Characteristics (hereafter ‘IAC’) widely known as Lamarck's evolutionary theory provided the theoretical frame on the origin of instinct and the heredity of action that the parental generation's habits were converted into the nature of the offspring generation. Contrary to conventional knowledge, this theory was not originally invented by Lamarck, and Darwin also did not discard this theory even after discovering the theory of natural selection in 1838 and maintained it throughout his intellectual life. Above all, in the field of epigenetics, the theory of ‘IAC’ has gained attention as a reliable scientific theory today. Darwin discovered crucial errors in the late 1830s that the Lamarck version's theory of ‘IAC’ did not adequately account for the principle of the inheritance of unconscious behavior like instinct. Lamarck's theory regarded habits as conscious and willful acts and saw that those habits are transmitted through the brain to control conscious actions. Lamarck's theory could not account for the complex and elaborate instincts of invertebrate animals, such as brainless ants. Contrary to Lamarck's view, Darwin established the new theory of ‘IAC’ that could be combined with contemporary neurological theory, which explains the heredity of unconscious behavior. Based on the knowledge of neurology, Darwin was able to translate the ‘principle of habit’ into a neurological term called ‘principle of reflex’. This article focuses on how Darwin join the theory of ‘IAC’ with nineteenth century neuroscience and how the neurological knowledge from the nineteenth century contributed to Darwin's overcoming of Lamarck's ‘IAC’. The significance of this study is to elucidate Darwin's notion of ‘IAC’ theory rather than natural selection theory as a principle of heredity of behavior. The theory of ‘IAC’ was able to account for the rapid variation of instincts in a relatively short period of time, unlike natural selection, which operates slowly in geological time spans of tens of millions of years. The nineteenth century neurological theory also provided neurological principles for ‘plasticity of instinct,’ empirically supporting the fact that all nervous systems responsible for reflexes respond sensitively to very fine stimuli. However, researchers of neo-Darwinian tendencies, such as Richard Dawkins and evolutionary psychologists advocating the ‘selfish gene’ hypothesis, which today claim to be Darwin's descendants, are characterized by human nature embedded in biological information, such as the brain and genes, so that it cannot change at all. This study aims to contribute to reconstructing the evolutionary discourse by illuminating Darwin's insights into the “plasticity of nature” that instincts can change relatively easily even at the level of invertebrates such as earthworms.


Subject(s)
Animals , Ants , Brain , Epigenomics , Ganglion Cysts , Heredity , Human Characteristics , Humans , Instinct , Invertebrates , Nervous System , Neurology , Neurosciences , Oligochaeta , Parents , Psychology , Reflex , Selection, Genetic , Spinal Cord , Sympathetic Nervous System , Transcutaneous Electric Nerve Stimulation , Wills
15.
Article in English | WPRIM | ID: wpr-761751

ABSTRACT

Human infections due to the monkey malaria parasite Plasmodium knowlesi is increasingly being reported from most Southeast Asian countries specifically Malaysia. The parasite causes severe and fatal malaria thus there is a need for urgent measures for its control. In this study, the level of polymorphisms, haplotypes and natural selection of full-length pkmsp8 in 37 clinical samples from Malaysian Borneo along with 6 lab-adapted strains were investigated. Low levels of polymorphism were observed across the full-length gene, the double epidermal growth factor (EGF) domains were mostly conserved, and non-synonymous substitutions were absent. Evidence of strong negative selection pressure in the non-EGF regions were found indicating functional constrains acting at different domains. Phylogenetic haplotype network analysis identified shared haplotypes and indicated geographical clustering of samples originating from Peninsular Malaysia and Malaysian Borneo. This is the first study to genetically characterize the full-length msp8 gene from clinical isolates of P. knowlesi from Malaysia; however, further functional characterization would be useful for future rational vaccine design.


Subject(s)
Asian Continental Ancestry Group , Borneo , Epidermal Growth Factor , Genetic Variation , Haplorhini , Haplotypes , Humans , Malaria , Malaysia , Merozoites , Parasites , Plasmodium knowlesi , Selection, Genetic
16.
Article in Korean | WPRIM | ID: wpr-787419

ABSTRACT

Like the body of Hominin, mind is the result of natural selection. Therefore, an evolutionary approach in the biological aspects is essential for an intrinsic understanding of mental disorders. However, the evolutionary medical approach to mental disordershas not been well researched because evolutionary psychiatry is not widely accepted, and the conceptual paradigm has not been unified. Nevertheless, some evolutionary hypotheses about some mental disorders have been proposed, including the following: 1) thesimple disease argument that mental disorder is a mere disease, 2) the genomic lag hypothesis that current genes are incompatible with evolutionary environmental changes, 3) the developmental mismatch hypothesis that brain development cannot reflect entire-information of surrounding environment, 4) the trade-off hypothesis that costs are offset by other adaptive benefits, 5) the by-product hypothesis that mental disorders are inevitable outcome of evolutionary design, 6) the cliff-edge model that the encephalizationin the Hominin caused mental disorders, 7) the inclusive fitness hypothesis that costs of individual are compensated by benefits of kinship, 8) the antagonistic polymorphism hypothesis that differential costs and benefits according to sex or age cause ofpolymorphic psychological traits 9) the heterozygote advantage hypothesis that the heterozygous genotypes have higher relative fitness, so they can persist even though homozygous genotypes cause mental disorders, and 10) a genomic imprinting hypothesis that conflicts between maternal genes and paternal genes cause mental disorders. I will summarize and compare the evolutionary hypotheses of mental disorders and present the lim itations of each hypothesis.


Subject(s)
Brain , Cost-Benefit Analysis , Genomic Imprinting , Genotype , Heterozygote , Hominidae , Humans , Mental Disorders , Selection, Genetic
17.
Electron. j. biotechnol ; 32: 35-40, Mar. 2018. ilus, tab
Article in English | LILACS | ID: biblio-1022620

ABSTRACT

Background: Poor reproductive efficiency of river buffalos hampers the production capabilities of animals. Buffalos are mainly considered poor breeders owing to the constrained expression of estrus behavior. Failure to display heat signs is an indication of improper functionality of signaling peptides to trigger on a series of behavioral changes, which can be detectable by breeders for timely insemination of females. This might cause an animal to be a repeat breeder. Genomic variations underlying synthesis of signaling peptides can be a useful marker to select superior animals with better reproductive efficiency. In this context, the current study was designed to analyze the CYP19A1 gene in Nili-Ravi buffalo. Results: A total of 97 animals were selected and were divided into two groups on the basis of their heat score. PCR amplification and sequencing of the amplicons were performed using the specific sets of primer, and then, sequences were analyzed for novel variants. A total of 11 polymorphic sites were identified illustrating phenotypic variation in the heat score. Most of the loci were found homologous. Single Nucleotide Polymorphisms (SNPs) were analyzed for association with silent estrus. A three-dimensional protein model was also generated to locate the position of exonic SNPs. Conclusion: This study illustrated that polymorphic sites in the CYP19A1 gene provided potential markers for selection of buffalos with better estrus behavior.


Subject(s)
Animals , Female , Pregnancy , Estrus/genetics , Buffaloes/genetics , Aromatase/genetics , Cytochrome P-450 Enzyme System/genetics , Pakistan , Selection, Genetic , Breeding , Polymerase Chain Reaction , Polymorphism, Single Nucleotide , Intracellular Signaling Peptides and Proteins , Insemination
18.
Electron. j. biotechnol ; 31: 1-9, Jan. 2018. ilus, graf, tab
Article in English | LILACS | ID: biblio-1022023

ABSTRACT

Background: Lettuce is a globally important leafy vegetable and a model plant for biotechnology due to its adaptability to tissue culture and stable genetic transformation. Lettuce is also crucial for functional genomics research in the Asteraceae which includes species of great agronomical importance. The development of transgenic events implies the production of a large number of shoots that must be differentiated between transgenic and non-transgenic through the activity of the selective agent, being kanamycin the most popular. Results: In this work we adjusted the selection conditions of transgenic seedlings to avoid any escapes, finding that threshold concentration of kanamycin was 75 mg/L. To monitor the selection system, we studied the morphological response of transgenic and non-transgenic seedlings in presence of kanamycin to look for a visual morphological marker. Several traits like shoot length, primary root length, number of leaves, fresh weight, and appearance of the aerial part and development of lateral roots were affected in non-transgenic seedlings after 30 d of culture in selective media. However, only lateral root development showed an early, qualitative and reliable association with nptII presence, as corroborated by PCR detection. Applied in successive transgenic progenies, this method of selection combined with morphological follow-up allowed selecting the homozygous presence of nptII gene in 100% of the analyzed plants from T2 to T5. Conclusions: This protocol allows a simplified scaling-up of the production of multiple homozygous transgenic progeny lines in the early generations avoiding expensive and time-consuming molecular assays.


Subject(s)
Plants, Genetically Modified/genetics , Lettuce/genetics , Selection, Genetic , Kanamycin/analysis , Polymerase Chain Reaction , Lettuce/chemistry , Seedlings , Homozygote
20.
Electron. j. biotechnol ; 30: 58-63, nov. 2017. ilus, tab, graf
Article in English | LILACS | ID: biblio-1021458

ABSTRACT

Background: Mutation breeding is one of the most important routes to achieving high docosahexaenoic acid (DHA) productivity using Schizochytrium. However, few selection strategies have been reported that aim to generate a high DHA content in Schizochytrium lipids. Results: First, culture temperature altered the butanol tolerance of Schizochytrium limacinum B4D1. Second, S. limacinum E8 was obtained by selecting mutants with high butanol tolerance. This mutant exhibited a 17.97% lower proportion of DHA than the parent strain S. limacinum B4D1. Third, a negative selection strategy was designed in which S. limacinum F6, a mutant with poor butanol tolerance, was obtained. The proportion of DHA in S. limacinum F6 was 11.22% higher than that of parent strain S. limacinum B4D1. Finally, the performances of S. limacinum B4D1, E8 and F6 were compared. These three strains had different fatty acid profiles, but there was no statistical difference in their biomasses and lipid yields. Conclusion: It was feasible to identified the relative DHA content of S. limacinum mutants based on their butanol tolerance.


Subject(s)
Docosahexaenoic Acids/biosynthesis , Butanols/metabolism , Stramenopiles/genetics , Stramenopiles/metabolism , Selection, Genetic , Temperature , Eicosapentaenoic Acid/metabolism , Biomass , Butanols/toxicity , Fatty Acids/metabolism , Fatty Acids/chemistry , Stramenopiles/drug effects , Fermentation , Mutation
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