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1.
Genet Mol Res ; 16(3)2017 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-28973734

RESUMO

The aim of this study was to evaluate repeated measures over the years to estimate repeatability coefficient and the number of the optimum measure to select superior genotypes in Annona muricata L. The fruit production was evaluated over 16 years in 71 genotypes without an experimental design. The estimation of variance components and the prediction of the permanent phenotypic value were performed using REML/BLUP proceedings. The coefficient of determination, accuracy, and selective efficiency increased when measures increased. The coefficient of determination of 80% was reached beyond 8 crop seasons with high accuracy and selective efficiency. Thus, the evaluation of 8 crop seasons can be suitable to select superior genotypes in the A. muricata L. breeding program. Predicted selection gain had a high magnitude for fruit production indicating that it is possible to take a progressive genetic advance for this trait over cycle breeding.


Assuntos
Annona/genética , Genótipo , Melhoramento Vegetal/métodos , Seleção Genética , Melhoramento Vegetal/normas , Polimorfismo Genético , Seleção Artificial
2.
Genet Mol Res ; 16(2)2017 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-28613374

RESUMO

Repeatability studies on fruit species are of great importance to identify the minimum number of measurements necessary to accurately select superior genotypes. This study aimed to identify the most efficient method to estimate the repeatability coefficient (r) and predict the minimum number of measurements needed for a more accurate evaluation of soursop (Annona muricata L.) genotypes based on fruit yield. Sixteen measurements of fruit yield from 71 soursop genotypes were carried out between 2000 and 2016. In order to estimate r with the best accuracy, four procedures were used: analysis of variance, principal component analysis based on the correlation matrix, principal component analysis based on the phenotypic variance and covariance matrix, and structural analysis based on the correlation matrix. The minimum number of measurements needed to predict the actual value of individuals was estimated. Principal component analysis using the phenotypic variance and covariance matrix provided the most accurate estimates of both r and the number of measurements required for accurate evaluation of fruit yield in soursop. Our results indicate that selection of soursop genotypes with high fruit yield can be performed based on the third and fourth measurements in the early years and/or based on the eighth and ninth measurements at more advanced stages.


Assuntos
Annona/genética , Frutas/anatomia & histologia , Fenótipo , Melhoramento Vegetal/métodos , Análise de Variância , Annona/anatomia & histologia , Interpretação Estatística de Dados , Frutas/genética , Variação Genética , Característica Quantitativa Herdável
3.
Genet Mol Res ; 15(4)2016 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-27886330

RESUMO

Brazil is among the five largest producers of cotton in the world, cultivating the species Gossypium hirsutum L. r. latifolium Hutch. The cultivars should have good fiber quality as well as yield. Genetic improvement of fiber traits requires the study of the genetic structure of the populations under improvement, leading to the identification of promising parent plants. To this end, it is important to acquire some information, such as estimates of genetic variance components and heritability coefficients, which will support the appropriate choice of the breeding strategy to be employed as well as enable the estimation of gains from selection. This study aimed to evaluate some agronomic characteristics, such as fiber quality and yield, estimating genetic parameters for the purpose of predicting earnings. Twelve cultivars of cotton, including four male progenitors (CNPA 01-42, BRS Verde, Glandless, and Okra leaf) and eight female progenitors (Delta opal, CNPA 7H, Aroeira, Antares, Sucupira, Facual, Precoce 3, and CNPA 8H), were used in performing crosses according to design I, proposed by Comstock and Robinson (1948). The experimental design was a randomized block with four replications. We observed genetic variability among all traits as well as higher efficiency of selection for the gains related to traits. Our results showed that the combined selection presented the highest genetic gains for all traits. For fiber length, the female/male selection and the combined selection resulted in the highest genetic gain.


Assuntos
Variação Genética , Gossypium/genética , Locos de Características Quantitativas , Brasil , Fibra de Algodão , Fenótipo , Melhoramento Vegetal
4.
Endocrinol. nutr. (Ed. impr.) ; 51(9): 497-505, nov. 2004. ilus
Artigo em Es | IBECS | ID: ibc-35931

RESUMO

Las complicaciones vasculares son la primera causa de morbimortalidad en la diabetes mellitus. La disfunción endotelial es el primer eslabón en la cadena de mecanismos fisiopatológicos que conducen a la vasculopatía diabética, tanto en vasos de conductancia (macroangiopatía) como de resistencia (microangiopatía). La disfunción endotelial (la reducción de las respuestas vasodilatadoras dependientes de endotelio, con o sin aumento de las respuestas vasoconstrictoras) es un fenómeno que se asocia con el mantenimiento de hiperglucemias sostenidas y el incremento del estrés oxidativo de la diabetes. Se han estudiado múltiples mecanismos que pueden aumentar los valores de especies reactivas de oxígeno y producir alteraciones de la función endotelial. En este sentido, se ha propuesto que la propia hiperglucemia per se es capaz de producir este efecto. Sin embargo, la mayor parte de los investigadores manifiesta que el aumento sostenido de los valores plasmáticos de glucosa modifica diferentes vías enzimáticas que, a su vez, originan un incremento del estrés oxidativo y eventualmente disfunción endotelial. Así, se han implicado enzimas como la aldosa-reductasa, la proteincinasa C, la polimerasa poli(ADP-ribosa), así como los receptores de endotelina, entre otros mecanismos. También se han propuesto mecanismos no enzimáticos, como la glucosilación de proteínas, como fuente de especies reactivas de oxígeno, con especial atención a los productos finales del proceso de glucosilación, los denominados productos terminales de glucosilación avanzada. Sin embargo, nuestro grupo mantiene desde hace años la hipótesis de que los productos tempranos e intermedios del proceso de glucosilación proteínica (los productos de Amadori) son capaces de liberar especies reactivas de oxígeno y pueden tener un papel relevante en el desarrollo de la disfunción endotelial y, eventualmente, de la vasculopatía diabética (AU)


Assuntos
Humanos , Diabetes Mellitus/complicações , Angiopatias Diabéticas/etiologia , Produtos Finais de Glicação Avançada/metabolismo , Fatores de Crescimento Endotelial/deficiência , Endotelinas/metabolismo , Radicais Livres/metabolismo , Proteínas Quinases/metabolismo
5.
Alcohol Clin Exp Res ; 17(4): 887-93, 1993 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8214431

RESUMO

Prenatal ethanol exposure reduces the density of the N-methyl-D-aspartate (NMDA) receptor agonist binding sites and decreases the capacity to elicit long-term potentiation (LTP) in hippocampal formation of 45-day-old rat offspring. We hypothesized that prenatal ethanol exposure would reduce metabotropic-glutamate receptor (mGluR)-activated phosphoinositide hydrolysis also. Sprague-Dawley rat dams were fed a liquid diet containing either 3.35% (v/v) ethanol or 5.0% ethanol throughout gestation. Control groups were pair-fed either isocalorically matched 0% ethanol liquid diets or lab chow ad libitum. (1S,3R)-1-aminocyclopentane-1,3-dicarboxylic acid (trans-ACPD) stimulated inositol-1-phosphate (IP1) accumulation via activation of the mGluR in offspring whose mothers consumed the 3.35% ethanol liquid diet was not different compared with the control groups. Furthermore, trans-ACPD stimulated IP1 accumulation in 10- to 13-day-old offspring of the 5.0% ethanol diet group was not different compared with the control groups. However, trans-ACPD stimulated IP1 accumulation was reduced significantly in 56- to 82-day-old offspring of dams fed the 5.0% ethanol liquid diet compared with the control groups. In contrast, bethanechol stimulated IP1 accumulation, mediated via activation of muscarinic cholinergic receptors, was not affected by maternal consumption of either ethanol liquid diet. These results suggest both dose- and age-dependent effects of prenatal ethanol exposure on hippocampal responsiveness to trans-ACPD-activated phosphoinositide hydrolysis. Furthermore, the ability of the 3.35% ethanol diet to alter hippocampal NMDA receptors without altering the mGluR response suggests a differential sensitivity to the effects of ethanol exposure in utero among hippocampal glutamate receptor subtypes.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Etanol/toxicidade , Transtornos do Espectro Alcoólico Fetal/fisiopatologia , Hipocampo/efeitos dos fármacos , Potenciação de Longa Duração/efeitos dos fármacos , Fosfatidilinositóis/metabolismo , Receptores de Glutamato/efeitos dos fármacos , Receptores de N-Metil-D-Aspartato/efeitos dos fármacos , Animais , Técnicas de Cultura , Relação Dose-Resposta a Droga , Etanol/farmacocinética , Feminino , Hipocampo/fisiopatologia , Hidrólise , Potenciação de Longa Duração/fisiologia , Gravidez , Ratos , Receptores de Glutamato/fisiologia , Receptores de N-Metil-D-Aspartato/fisiologia
6.
Alcohol ; 9(1): 37-41, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1346364

RESUMO

The effect of ethanol exposure during different periods of prenatal or postnatal development on hippocampal N-methyl-D-aspartate (NMDA) receptor binding was studied in rat. Fetal rat pups were exposed to ethanol for different periods of time during gestation via maternal consumption of a 3.35% ethanol liquid diet. In a separate experiment, neonatal pups were fed 2.51 g ethanol/kg body weight/day from Postnatal Day (PD) 4 to PD 10 via intragastric feeding tube. These two ethanol administration paradigms produced average peak maternal and pup blood ethanol concentrations of 39 mg/dl and 57 mg/dl, respectively. At 45 days of age, offspring from each treatment group were sacrificed for measurements of hippocampal NMDA-sensitive [3H]-glutamate binding site density using in vitro radiohistochemical techniques. As observed previously, prenatal ethanol exposure throughout gestation resulted in NMDA-sensitive [3H]-glutamate binding site reductions in the apical dendritic field regions of dentate gyrus, hippocampal CA1 and subiculum of dorsal hippocampal formation compared to the ad lib or pair-fed control groups. NMDA-sensitive [3H]-glutamate binding was not different than control in rats exposed to ethanol during the first half of gestation only. Prenatal ethanol exposure during the last half or the last third of gestation resulted in NMDA-sensitive [3H]-glutamate binding site reductions comparable to the binding site reductions observed in rats exposed to ethanol throughout gestation. Hippocampal NMDA-sensitive [3H]-glutamate binding site density in postnatal ethanol-exposed rats was not different than the suckling or gastrostomy control groups.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Etanol/farmacologia , Idade Gestacional , Hipocampo/metabolismo , Efeitos Tardios da Exposição Pré-Natal , Receptores de N-Metil-D-Aspartato/metabolismo , Envelhecimento , Animais , Animais Recém-Nascidos/metabolismo , Etanol/administração & dosagem , Feminino , Glutamatos/metabolismo , Ácido Glutâmico , N-Metilaspartato/farmacologia , Gravidez , Ratos
7.
Rev Gastroenterol Mex ; 56(2): 91-5, 1991.
Artigo em Espanhol | MEDLINE | ID: mdl-1947622

RESUMO

Between 1978-1990 three patients were surgically treated with different kinds of intestinal endometriosis at the Instituto Nacional de la Nutrición Salvador Zubirán in Mexico City. The first patient had acute appendicitis without dysmenorrhea or pelvic endometriosis detected during laparotomy. The second patient had incomplete intestinal obstruction related to ileo-cecal involvement. She clinically had dysmenorrhea and were found multiple endometriosis implants during operation. After the ileocecal excision suppressive hormonal therapy was given, the patient developed side effects, then surgical resection of the uterus and ovaries were performed. The third patient was a 48-year-old woman who developed a progressive lower intestinal obstruction. She underwent a three-time operative procedure. Lower sigmoid resection was performed and no endometriosis implants or metastatic disease were found. Postoperative course was uneventful in all patients, no mucosal involvement or associated carcinoma was found. Surgical resection of the affected portions of the bowel was highly effective in each case.


Assuntos
Endometriose/cirurgia , Neoplasias Intestinais/cirurgia , Adulto , Neoplasias do Apêndice/patologia , Neoplasias do Apêndice/cirurgia , Endometriose/patologia , Feminino , Humanos , Neoplasias do Íleo/patologia , Neoplasias do Íleo/cirurgia , Valva Ileocecal , Neoplasias Intestinais/patologia , Metástase Linfática , Pessoa de Meia-Idade , Neoplasias do Colo Sigmoide/patologia , Neoplasias do Colo Sigmoide/cirurgia
8.
Angiologia ; 43(1): 7-10, 1991.
Artigo em Espanhol | MEDLINE | ID: mdl-2035885

RESUMO

In this work we have tried to elucidate whether telangiectases are dilatations of the arteriolar or the venular sections of the circulation system. To this end, we have made use of resources which have allowed us to study in the first place, the wall of these small vascular dilatations and, in the second place, their content. Through our studies we could determine that telangiectases are originated by dilatation of the venular sector of the circulatory system.


Assuntos
Telangiectasia/etiologia , Arteríolas/patologia , Tecido Conjuntivo/patologia , Dilatação Patológica/patologia , Humanos , Microscopia Eletrônica , Telangiectasia/patologia , Vênulas/patologia
11.
Gen Pharmacol ; 13(2): 117-23, 1982.
Artigo em Inglês | MEDLINE | ID: mdl-7095390

RESUMO

1. 5-Hydroxytryptamine (5-HT) induced dose-dependent contractions in the isolated cat femoral artery, which were reduced by LSD, methysergide, phentolamine and reserpine pretreatment (only at low doses). 2. Pentobarbital (PB) and Mn/+ relaxed the arteries previously contracted with 5-HT. These drugs reduced the contraction evoked by this amine as it was Ca2+-suppression. 3. High concentrations of 5-HT and K+ induced tritium release from vessels prelabelled with 3H-noradrenaline. Ca2+-deprivation and PB unmodified the release caused by 5-HT, but that elicited by K+ was abolished. 4. These data indicate that 5-HT-induced contraction is essentially due to direct interaction of this agent with 5-HT-receptors, and that PB interferes with Ca2+ entry to the cell.


Assuntos
Vasos Sanguíneos/metabolismo , Norepinefrina/metabolismo , Pentobarbital/farmacologia , Serotonina/farmacologia , Vasoconstrição/efeitos dos fármacos , Animais , Vasos Sanguíneos/efeitos dos fármacos , Cálcio/fisiologia , Bloqueadores dos Canais de Cálcio/farmacologia , Gatos , Artéria Femoral/efeitos dos fármacos , Técnicas In Vitro , Manganês/farmacologia , Receptores Adrenérgicos/efeitos dos fármacos , Receptores de Serotonina/efeitos dos fármacos , Serotonina/fisiologia
12.
Gen Pharmacol ; 13(2): 125-32, 1982.
Artigo em Inglês | MEDLINE | ID: mdl-6807742

RESUMO

1. Tyramine and noradrenaline (NA) caused dose-dependent contractions in middle cerebral and femoral arteries of cat, which were decreased by phentolamine. 2. Gangliectomy increased the contraction evoked by NA in brain arteries. 3. Reserpine pretreatment and/or gangliectomy reduced the contraction caused by tyramine, the maximal responses being unmodified in the cerebral vessels. 4. Tyramine induced Ca2+-dependent tritium release from brain and femoral arteries, which was reduced by reserpine pretreatment and/or gangliectomy. 5. These data suggest that tyramine has a direct component, apart from an indirect one, in brain arteries. The mechanisms by which NA induces slight contraction in them, including the role of Ca2+, are postulated.


Assuntos
Norepinefrina/farmacologia , Tiramina/farmacologia , Vasoconstrição/efeitos dos fármacos , Animais , Cálcio/fisiologia , Gatos , Artérias Cerebrais/efeitos dos fármacos , Artérias Cerebrais/metabolismo , Ácido Egtázico/farmacologia , Feminino , Artéria Femoral/efeitos dos fármacos , Artéria Femoral/metabolismo , Técnicas In Vitro , Masculino , Norepinefrina/metabolismo , Especificidade de Órgãos , Fentolamina/farmacologia
13.
J Neurosurg ; 55(4): 543-9, 1981 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7277003

RESUMO

This study analyzes the changes induced by subarachnoid hemorrhage (SAH) on the contractile responses and the noradrenaline release evoked in cat cerebral arteries by histamine. The dose-dependent vasoconstriction induced by histamine on the cerebral arteries of normal cats was significantly reduced by diphenhydramine and phentolamine. When SAH was produced 3 and 7 days before the experiment, the histamine-induced vasoconstriction also decreased. Thereafter, a tendency to normalization in the contractile vascular responses was observed such that in 15 days after the hemorrhage it was not significantly different from that found in controls animals. The decrease in the contractile responses to histamine provoked by SAH was similar to that seen after pretreatment with intracisternal injections of 6-hydroxydopamine. The amount of radioactivity released by histamine following preincubation with 3H-noradrenaline from the cerebral arteries of cats exposed to SAH 3, 7, and 15 days before the experiment was significantly reduced when compared with controls. Moreover, the basal level of tritium release and the radioactivity retained at the end of the experiment were also decreased after SAH. These decreases were less marked 15 days after SAH. Intracisternal injections of 6-hydroxydopamine 3, 7, and 15 days prior to the assay, and the removal of both superior cervical ganglia 15 days before the experiment, also markedly reduced these three parameters. These results indicate that histamine releases noradrenaline from cat cerebral arteries, and SAH produces a transient denervation of the perivascular adrenergic nerve endings. The inhibition of the histamine-induced vasoconstriction observed after SAH might be explained by the impairment of the indirect adrenergic mechanism involved in the overall contractile response elicited by this amine in cerebral arteries. According to the present findings, histamine does not seem to play a significant role in the production of the cerebral vasospasm occurring after SAH.


Assuntos
Artérias Cerebrais/fisiopatologia , Histamina/farmacologia , Norepinefrina/metabolismo , Hemorragia Subaracnóidea/fisiopatologia , Vasoconstrição/efeitos dos fármacos , Animais , Gatos , Artérias Cerebrais/efeitos dos fármacos , Artérias Cerebrais/inervação , Feminino , Hidroxidopaminas/farmacologia , Técnicas In Vitro , Ataque Isquêmico Transitório/fisiopatologia , Masculino , Trítio/metabolismo
16.
J Pharm Pharmacol ; 32(9): 643-6, 1980 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-6107366

RESUMO

The release of tritium (3H) evoked by tyramine, potassium (K+) and 5-hydroxytryptamine (5-HT) from goat pial arteries preloaded with [3H]noradrenaline (3H-NA) was studied. In normal Krebs-bicarbonate solution (KBS) all these agents caused a transient increase in radioactivity release over the basal spontaneous outflow. The pattern of release evoked by 5-HT was similar to that induced by tyramine with a slow onset and decline, but different from that induced by K+ which produced a rapid peak of 3H release followed by a quick fall. The removal of Ca2+ from the medium did not modify the efflux of radioactivity caused by tyramine, but the 3H efflux produced by K+ was markedly reduced. Nevertheless, in this Ca2+-free medium the 3H release evoked by 5-HT was partially, but significantly, decreased. These results indicate that K+ evokes NA release by a Ca/+-dependent process, probably of an exocytotic nature, while tyramine mediates NA release by means of a Ca2+-independent mechanism. However, 5-HT possesses a Ca2+-dependent and a tyramine-like component.


Assuntos
Cálcio/farmacologia , Norepinefrina/metabolismo , Pia-Máter/irrigação sanguínea , Potássio/farmacologia , Serotonina/farmacologia , Tiramina/farmacologia , Animais , Artérias/efeitos dos fármacos , Artérias/metabolismo , Interações Medicamentosas , Cabras , Técnicas In Vitro
18.
J Pharm Pharmacol ; 31(12): 818-21, 1979 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-43365

RESUMO

Pial arteries of cats were used to analyse the effects of 5-hydroxytryptamine (5-HT) on the release of [3H]noradrenaline. To achieve this the vessels were preincubated with [3H]noradrenaline and the effect of different concentrations of 5-HT (10(-6), 10(-5), 10(-4) M) on the release of tritium was studied. 5-HT elicited release of radioactivity in a dose-dependent manner. Removal of both superior cervical sympathetic ganglia 15 days before the experiment of pretreatment of the animals with reserpine (3 mg kg-1, total dose) produced a significant decrease in the outflow of tritium induced by 5-HT. In these arteries, the amount of radioactivity retained at the end of the experiment was much diminished. Cocaine (10(-6) M) caused a significant decrease in the tritium efflux induced by 5-HT (1"0(-5) M). These results show that 5-HT has an indirect adrenergic effect in the pial arteries of the cat only at high doses of 5-HT, and confirm that sympathetic innervation of these vessels mainly comes from the superior cervical ganglia.


Assuntos
Norepinefrina/metabolismo , Pia-Máter/irrigação sanguínea , Serotonina/farmacologia , Animais , Artérias/efeitos dos fármacos , Artérias/inervação , Artérias/metabolismo , Atropina/farmacologia , Gatos , Denervação , Feminino , Masculino , Pentobarbital/farmacologia , Reserpina/farmacologia , Fatores de Tempo
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