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1.
Zygote ; 26(4): 333-335, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30277454

RESUMO

SummaryThe aim of this study was to evaluate the effect of incubating semen for different periods (90, 270 or 450 min) with or without Trolox® (100 or 150 µM) on the quality of sperm from Saimiri collinsi. Sperm motility, vigour, and plasma membrane integrity (PMI) were evaluated in both fresh semen and semen incubated for different time periods, i.e. 90, 270 or 450 min of incubation. Supplementation of semen extender with Trolox® 100 µM improved sperm motility, vigour and PMI for up to 270 min of incubation.


Assuntos
Cromanos/farmacologia , Criopreservação/veterinária , Crioprotetores/farmacologia , Saimiri/fisiologia , Preservação do Sêmen/veterinária , Espermatozoides/fisiologia , Animais , Antioxidantes/farmacologia , Membrana Celular , Masculino , Análise do Sêmen , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos
2.
Genet Mol Res ; 14(3): 7274-8, 2015 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-26214405

RESUMO

Herein, we describe 34 microsatellite loci developed using an enrichment genomic library for the tree species Hancornia speciosa Gomes (Apocynaceae). Thirty-five individuals were genotyped using 34 primers to analyze the polymorphisms at each locus. The number of alleles per locus ranged from 4 to 20. The average number of alleles was 8.11, and the expected heterozygosity ranged from 0.62 to 0.94. These microsatellite primers will be useful in population genetics studies for this species.


Assuntos
Apocynaceae/genética , Repetições de Microssatélites/genética , Genética Populacional , Genótipo , Polimorfismo Genético , Árvores/genética
3.
Braz J Biol ; 84: e281286, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38629678

RESUMO

Salinity reduces feijão-caupi production, and the search for tolerant varieties becomes important within the agricultural context, as, in addition to being used in the field, they can be used in genetic improvement. The objective was to for a identify variety that is tolerant to salinity considering the physiological quality of seeds and seedling growth. A 2 × 4 factorial scheme was used, referring to the varieties Pingo-de-ouro and Coruja, and four electrical conductivities of water (0; 3.3; 6.6 and 9.9 dS m-1). The physiological quality of seeds and the growth of seedlings were analyzed, in addition to the cumulative germination. The Pingo-de-ouro variety showed no germination, length of the shoot and root, dry mass of the shoot and root compromised up to electrical conductivity of 6 dS m-1 in relation to 0.0 dS m-1. On the other hand, the Coruja variety showed reduced germination, increased shoot and root length. The creole variety Pingo-de-ouro proved to be tolerant to salinity.


Assuntos
Vigna , Vigna/genética , Salinidade , Cloreto de Sódio , Plântula , Germinação/fisiologia , Sementes/fisiologia
4.
Zygote ; 21(2): 167-71, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-22475447

RESUMO

There is no tradition in studies reporting the effect of exposure to cryoprotectants or simply hypoxia and hypothermia on gene expression in the ovarian tissue and there has been only one study on reference or target genes quantification, and comparisons of normoxic with hypoxic, hypothermic and toxic conditions. Our aim in the present study was to investigate the stability of three reference genes in the ovarian tissue of capuchin monkeys (Cebus apella). To this end, fresh and cryoprotectant-exposed ovarian biopsies were used. Both fresh and exposed ovarian tissues were subjected to total RNA extraction and synthesis of cDNA. cDNA was amplified by real-time polymerase chain reaction (PCR), and GeNorm, BestKeeper and NormFinder software were used to evaluate the stability of glyceraldehyde-2-phosphate dehydrogenase (GAPDH), hypoxanthine phosphoribosyltransferase 1 (HPRT1) and TATA-binding protein (TBP). Results demonstrated that, in the ovarian tissue from capuchin monkeys, HPRT1 and TBP were the most suitable reference genes and thus could be used as parameters to normalize data in future studies. In contrast, GAPDH appeared as the least stable gene among the tested reference genes. In conclusion, HPRT1 and TBP were the most stable reference genes in fresh and cryoprotectant-exposed ovarian tissue from capuchin monkeys.


Assuntos
Gliceraldeído-3-Fosfato Desidrogenases/genética , Hipoxantina Fosforribosiltransferase/genética , Ovário/efeitos dos fármacos , Padrões de Referência , Proteína de Ligação a TATA-Box/genética , Animais , Cebus , Crioprotetores/farmacologia , Feminino , Hipotermia , Ovário/citologia , Ovário/metabolismo , Oxigênio/farmacologia , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa
5.
Genet Mol Res ; 11(2): 1618-26, 2012 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-22782581

RESUMO

Many species are expected to suffer strong shifts in their geographic ranges due to climate changes in the next 50 years, with severe consequences for biodiversity patterns and population structure. We used here an ensemble forecast approach for obtaining species' range in which multiple species distribution models and climatic models were combined to model loss of genetic variability in Baru, Dipteryx alata (Fabaceae), an economically important Neotropical tree native to the Cerrado of Brazil. We estimated a series of genetic parameters (number of alleles per locus, expected heterozygosity under Hardy-Weinberg equilibrium and mutation-drift equilibrium) for this species based on eight microsatellite loci. We then recalculated these parameters assuming that local populations in areas of low future environmental suitability will go extinct. All genetic parameters remained approximately constant up to a 50% threshold of climatic suitability in the future; after this critical threshold there is an abrupt reduction in all parameters, although the magnitude of shift is only about 10% of current values, on average. Thus, despite the shifts in geographic range and climatically suitable areas towards southeastern Brazil, our analyses do not predict a strong loss of genetic diversity in D. alata because of the broad tolerance of this species, which ensures large future ranges, contrasting with other Cerrado species that have been analyzed in a similar manner.


Assuntos
Dipteryx/genética , Dipteryx/classificação , Variação Genética/genética , Geografia , Repetições de Microssatélites/genética
6.
Genet Mol Res ; 10(1): 321-5, 2011 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-21365547

RESUMO

We isolated and characterized 12 microsatellite loci for Tibouchina papyrus (Melastomataceae), an endangered species with narrow and disjunct range, endemics to a few localities in "cerrado rupestre" from Central Brazil. These microsatellites were obtained by sequencing of a genomic shotgun library for primer design. Leaves from 96 individuals collected in the three known local populations were genotyped using the 12 primers designed to analyze the polymorphisms at each locus. The number of alleles per locus ranged from one to six; two loci were monomorphic. Among the polymorphic loci, expected heterozygosities ranged from 0.161 to 0.714. Combined paternity exclusion probability was 0.957 and combined genetic identity (0.051) was high for studies on parentage. Tibouchina papyrus is a rare and endemic tree species of outcrop quartzite and sandstone soils, with highly isolated populations, which may have lead to the low degree of polymorphism that we detected. Also, motifs of most loci are larger than dinucleotide, which typically display lower levels of polymorphism.


Assuntos
Melastomataceae/genética , Repetições de Microssatélites/genética , Espécies em Perigo de Extinção , Polimorfismo Genético/genética
7.
RSC Adv ; 11(21): 12595-12606, 2021 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-35423788

RESUMO

We combine Density Functional Theory (DFT) and classical Molecular Dynamics (MD) simulations to study graphene-boron nitride (BN) hybrid monolayers spanning a wide range of sizes (from 2 nm to 100 nm). Our simulations show that the elastic properties depend on the fraction of BN contained in the monolayer, with Young's modulus values decreasing as the BN concentration increases. Furthermore, our calculations reveal that the mechanical properties are weakly anisotropic. We also analyze the evolution of the stress distribution during our MD simulations. Curiously, we find that stress does not concentrate on the graphene-BN interface, even though fracture always starts in this region. Hence, we find that fracture is caused by the lower strength of C-N and C-B bonds, rather than by high local stress values. Still, in spite of the fact that the weaker bonds in the interface region become a lower fraction of the total as size increases, we find that the mechanical properties of the hybrid monolayers do not depend on the size of the structure, for constant graphene/BN concentrations. Our results indicate that the mechanical properties of the hybrid monolayers are independent of scale, so long as the graphene sheet and the h-BN nanodomain decrease or increase proportionately.

8.
RSC Adv ; 11(56): 35127-35140, 2021 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-35493153

RESUMO

Hybrid structures comprised of graphene domains embedded in larger hexagonal boron nitride (h-BN) nanosheets were first synthesized in 2013. However, the existing theoretical investigations on them have only considered relaxed structures. In this work, we use Density Functional Theory (DFT) and Molecular Dynamics (MD) simulations to investigate the mechanical and electronic properties of this type of nanosheet under strain. Our results reveal that the Young's modulus of the hybrid sheets depends only on the relative concentration of graphene and h-BN in the structure, showing little dependence on the shape of the domain or the size of the structure for a given concentration. Regarding the tensile strength, we obtained higher values using triangular graphene domains. We find that the studied systems can withstand large strain values (between 15% and 22%) before fracture, which always begins at the weaker C-B bonds located at the interface between the two materials. Concerning the electronic properties, we find that by combining composition and strain, we can produce hybrid sheets with band gaps spanning an extensive range of values (between 1.0 eV and 3.5 eV). Our results also show that the band gap depends more on the composition than on the external strain, particularly for structures with low carbon concentration. The combination of atomic-scale thickness, high ultimate strain, and adjustable band gap suggests applications of h-BN nanosheets with graphene domains in wearable electronics.

9.
Braz J Biol ; 84: e252088, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34755814

RESUMO

Acacia mangium is a pioneer species with fast growth and frequently used in the recovery of degraded areas. The objectives were to evaluate insects and spiders, their ecological indices and interactions on A. mangium saplings in a tropical degraded area in recovering process. The experimental design was completely randomized with 24 replications, with treatments represented by the first and second years after A. mangium seedling planted. Numbers of leaves/branch, branches/sapling, and ground cover by A. mangium saplings, Hemiptera: Phenacoccus sp. and Pachycoris torridus; Hymenoptera: Tetragonisca angustula and Trigona spinipes, Brachymyrmex sp., Camponotus sp. and Cephalotes sp.; Blattodea: Nasutitermes sp. and Neuroptera: Chrysoperla sp.; abundance, species richness of pollinating insects, tending ants, and the abundance of Sternorrhyncha predators were greatest in the second year after planting. Numbers of Hemiptera: Aethalium reticulatum, Hymenoptera: Camponotus sp., Cephalotes sp., Polybia sp., T. angustula, T. spinipes, tending ants, pollinating insects, Sternorrhyncha predators and species richness of tending ants were highest on A. mangium saplings with greatest numbers of leaves or branches. The increase in the population of arthropods with ground cover by A. mangium saplings age increase indicates the positive impact by this plant on the recovery process of degraded areas.


Assuntos
Acacia , Insetos , Aranhas , Animais , Biomarcadores Ambientais , Recuperação e Remediação Ambiental
10.
Braz. j. biol ; 842024.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469259

RESUMO

Abstract Acacia mangium is a pioneer species with fast growth and frequently used in the recovery of degraded areas. The objectives were to evaluate insects and spiders, their ecological indices and interactions on A. mangium saplings in a tropical degraded area in recovering process. The experimental design was completely randomized with 24 replications, with treatments represented by the first and second years after A. mangium seedling planted. Numbers of leaves/branch, branches/sapling, and ground cover by A. mangium saplings, Hemiptera: Phenacoccus sp. and Pachycoris torridus; Hymenoptera: Tetragonisca angustula and Trigona spinipes, Brachymyrmex sp., Camponotus sp. and Cephalotes sp.; Blattodea: Nasutitermes sp. and Neuroptera: Chrysoperla sp.; abundance, species richness of pollinating insects, tending ants, and the abundance of Sternorrhyncha predators were greatest in the second year after planting. Numbers of Hemiptera: Aethalium reticulatum, Hymenoptera: Camponotus sp., Cephalotes sp., Polybia sp., T. angustula, T. spinipes, tending ants, pollinating insects, Sternorrhyncha predators and species richness of tending ants were highest on A. mangium saplings with greatest numbers of leaves or branches. The increase in the population of arthropods with ground cover by A. mangium saplings age increase indicates the positive impact by this plant on the recovery process of degraded areas.


Resumo Acacia mangium é uma espécie pioneira, de rápido crescimento e utilizada na recuperação de áreas degradadas. Os objetivos foram avaliar insetos e aranhas, seus índices ecológicos e interações com plantas de A. mangium em área tropical degradada em processo de recuperação. O delineamento experimental foi inteiramente casualizado com 24 repetições, com os tratamentos representados pelos primeiro e segundo anos após a plantio de A. mangium. Os números de folhas/galhos, galhos/plantas e cobertura do solo por plantas de A. mangium, de Hemiptera: Phenacoccus sp. e Pachycoris torridus; Hymenoptera: Tetragonisca angustula e Trigona spinipes, Brachymyrmex sp., Camponotus sp. e Cephalotes sp.; Blattodea: Nasutitermes sp. e Neuroptera: Chrysoperla sp.; a abundância, riqueza de espécies de insetos polinizadores, formigas cuidadoras e a abundância de predadores de Sternorrhyncha foram maiores no segundo ano após o plantio. Os números de Hemiptera: Aethalium reticulatum, Hymenoptera: Camponotus sp., Cephalotes sp., Polybia sp., T. angustula, T. spinipes, formigas cuidadoras, insetos polinizadores, predadores de Sternorrhyncha e a riqueza de espécies de formigas cuidadoras foram maiores em plantas de A. mangium com maior altura e número de folhas ou galhos. O aumento populacional de artrópodes e da cobertura do solo com o processo de envelhecimento das plantas de A. mangium indicam impacto positivo dessa planta na recuperação de áreas degradadas.

11.
Braz. j. biol ; 84: e252088, 2024. tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1345543

RESUMO

Abstract Acacia mangium is a pioneer species with fast growth and frequently used in the recovery of degraded areas. The objectives were to evaluate insects and spiders, their ecological indices and interactions on A. mangium saplings in a tropical degraded area in recovering process. The experimental design was completely randomized with 24 replications, with treatments represented by the first and second years after A. mangium seedling planted. Numbers of leaves/branch, branches/sapling, and ground cover by A. mangium saplings, Hemiptera: Phenacoccus sp. and Pachycoris torridus; Hymenoptera: Tetragonisca angustula and Trigona spinipes, Brachymyrmex sp., Camponotus sp. and Cephalotes sp.; Blattodea: Nasutitermes sp. and Neuroptera: Chrysoperla sp.; abundance, species richness of pollinating insects, tending ants, and the abundance of Sternorrhyncha predators were greatest in the second year after planting. Numbers of Hemiptera: Aethalium reticulatum, Hymenoptera: Camponotus sp., Cephalotes sp., Polybia sp., T. angustula, T. spinipes, tending ants, pollinating insects, Sternorrhyncha predators and species richness of tending ants were highest on A. mangium saplings with greatest numbers of leaves or branches. The increase in the population of arthropods with ground cover by A. mangium saplings age increase indicates the positive impact by this plant on the recovery process of degraded areas.


Resumo Acacia mangium é uma espécie pioneira, de rápido crescimento e utilizada na recuperação de áreas degradadas. Os objetivos foram avaliar insetos e aranhas, seus índices ecológicos e interações com plantas de A. mangium em área tropical degradada em processo de recuperação. O delineamento experimental foi inteiramente casualizado com 24 repetições, com os tratamentos representados pelos primeiro e segundo anos após a plantio de A. mangium. Os números de folhas/galhos, galhos/plantas e cobertura do solo por plantas de A. mangium, de Hemiptera: Phenacoccus sp. e Pachycoris torridus; Hymenoptera: Tetragonisca angustula e Trigona spinipes, Brachymyrmex sp., Camponotus sp. e Cephalotes sp.; Blattodea: Nasutitermes sp. e Neuroptera: Chrysoperla sp.; a abundância, riqueza de espécies de insetos polinizadores, formigas cuidadoras e a abundância de predadores de Sternorrhyncha foram maiores no segundo ano após o plantio. Os números de Hemiptera: Aethalium reticulatum, Hymenoptera: Camponotus sp., Cephalotes sp., Polybia sp., T. angustula, T. spinipes, formigas cuidadoras, insetos polinizadores, predadores de Sternorrhyncha e a riqueza de espécies de formigas cuidadoras foram maiores em plantas de A. mangium com maior altura e número de folhas ou galhos. O aumento populacional de artrópodes e da cobertura do solo com o processo de envelhecimento das plantas de A. mangium indicam impacto positivo dessa planta na recuperação de áreas degradadas.


Assuntos
Animais , Aranhas , Acacia , Insetos , Biomarcadores Ambientais , Recuperação e Remediação Ambiental
12.
Braz J Biol ; 78(2): 296-305, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29069161

RESUMO

In Brazil, the expansion of agricultural activity and the associated indiscriminate use of herbicides such as glyphosate is directly related to the loss of biodiversity in the Cerrado. The identification of plant species as bioindicators of herbicide action, especially species native to the area, can help in monitoring the impacts of xenobiotics in the remaining Cerrado. Thus, this study was designed to evaluate the possible use of the native Cerrado species Pouteria torta as a bioindicator of glyphosate action via changes in physiological performance. At 16 months after sowing, the effect of glyphosate was evaluated by applying the following doses: 0 (control), 25, 50, 100, 200, 400, 800, and 1200 g a.e. ha-1. In response to glyphosate, P. torta exhibited reductions in photosynthesis and chloroplastid pigment content, as well as accumulation of shikimic acid and the occurrence of chlorosis and necrosis. These changes demonstrate the high sensitivity of P. torta to glyphosate and its potential for use as a bioindicator of this herbicide.


Assuntos
Glicina/análogos & derivados , Herbicidas/efeitos adversos , Fotossíntese/efeitos dos fármacos , Pouteria/efeitos dos fármacos , Espécies Sentinelas/metabolismo , Brasil , Relação Dose-Resposta a Droga , Glicina/efeitos adversos , Pradaria , Pouteria/metabolismo , Glifosato
13.
Arq. bras. med. vet. zootec. (Online) ; 73(4): 781-790, Jul.-Aug. 2021. tab, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1285278

RESUMO

The objective of the present study was to Standardize a Polymerase Chain Reaction (PCR) protocol for the authentication of bovine and buffalo milk, and to detect the presence of Salmonella spp. and Listeria monocytogenes. For this, the target DNA was extracted, mixed, and subjected to a PCR assay. Milk samples were defrauded and experimentally contaminated with microorganisms to assess the detection of target DNA at different times of cultivation, bacterial titers, and concentration of genetic material. In addition, the protocol was tested with DNA extracted directly from food, without a pre-enrichment step. The proposed quadruplex PCR showed good accuracy in identifying target DNA sequences. It was possible to simultaneously identify all DNA sequences at the time of inoculation (0h), when the samples were contaminated with 2 CFU/250mL and with 6h of culture when the initial inoculum was 1 CFU/250mL. It was also possible to directly detect DNA sequences from the food when it was inoculated with 3 CFU/mL bacteria. Thus, the proposed methodology showed satisfactory performance, optimization of the analysis time, and a potential for the detection of microorganisms at low titers, which can be used for the detection of fraud and contamination.


O objetivo do presente estudo foi padronizar um protocolo de reação em cadeia da polimerase (PCR) para a autenticação de leite bovino e bubalino e a detecção da presença de Salmonella spp. e Listeria monocytogenes. Para isso, o DNA-alvo foi extraído, misturado e submetido ao ensaio de PCR. Amostras de leite foram fraudadas e contaminadas experimentalmente com os micro-organismos, para se avaliar a detecção do DNA-alvo em diferentes tempos de cultivo, os títulos bacterianos e a concentração de material genético. Além disso, o protocolo foi testado com DNA extraído diretamente do alimento, sem a etapa de pré-enriquecimento. A PCR quadriplex proposta mostrou boa precisão na identificação de sequências de DNA-alvo. Foi possível identificar simultaneamente todas as sequências de DNA no momento da inoculação (0h), quando as amostras estavam contaminadas com 2 UFC/250mL, e com seis horas de cultura, quando o inóculo inicial foi de 1 UFC/250mL. Também foi possível detectar diretamente as sequências de DNA do alimento quando este foi inoculado com 3 UFC/mL de bactérias. Dessa forma, a metodologia proposta apresentou desempenho satisfatório, otimização do tempo de análise e potencial para detecção de micro-organismos em baixos títulos, podendo ser utilizada para detecção de fraude e contaminação.


Assuntos
Animais , Bovinos , Salmonella/isolamento & purificação , Búfalos , Leite/microbiologia , Fraude/prevenção & controle , Listeria monocytogenes/isolamento & purificação , Inocuidade dos Alimentos/métodos , Reação em Cadeia da Polimerase Multiplex/veterinária
14.
Anim Reprod Sci ; 159: 118-23, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26071650

RESUMO

The objectives of the present study were to test the effect of coconut water solution (CWS), TES-TRIS and ACP-118(®) on the seminal cooling and cryopreservation of semen from capuchin monkeys (Sapajus apella). Semen was collected from six males by electro-ejaculation, diluted in TES-TRIS, CWS or ACP-118(®), and maintained at 4°C for 28h. Semen was subsequently evaluated (Experiment I) or cryopreserved in the presence of different glycerol concentrations (3%, 5% or 7%) (Experiment II). ACP-118(®) was the preferred extender to preserve sperm motility and viability after 28h incubation at 4°C. Cooled sperm were successfully frozen-thawed in a medium containing 3% glycerol. After thawing, sperm retained the capacity to fertilize oocytes and zygotes were obtained. In conclusion, ACP-118(®) can be effectively and efficiently used as extender for the cooling of S. apella semen. Furthermore, cryopreservation using ACP-118(®) by adding 3% glycerol is suitable to maintain sperm morphology and the capacity of these cells to fertilize in vitro.


Assuntos
Crioprotetores/farmacologia , Congelamento , Sêmen , Animais , Cebus , Cocos , Criopreservação/métodos , Masculino , Sêmen/efeitos dos fármacos
15.
Br J Pharmacol ; 77(4): 597-604, 1982 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-6129910

RESUMO

1 Contractile responses produced by the alpha 1-adrenoceptor selective agonist, phenylephrine, and the alpha 2-adrenoceptor selective agonists, oxymetazoline and clonidine, have been compared to those produced by noradrenaline (non selective) in the rat aorta. 2 The relative order of potency of the agonists was noradrenaline greater than phenylephrine greater than clonidine greater than oxymetazoline. Noradrenaline and phenylephrine produced similar maximal responses. The maximal responses produced by oxymetazoline and clonidine were about 59% and 24% respectively of those produced by noradrenaline. 3 Concentrations of agonists producing maximal contractions exhibited different response-time relationships. Responses to noradrenaline and phenylephrine were biphasic while responses induced by oxymetazoline and clonidine were monophasic. 4 In calcium-free solution, contractions stimulated by oxymetazoline and clonidine were almost abolished while those stimulated by noradrenaline and phenylephrine were reduced by about 60-70%. The calcium entry blocker, cinnarizine, almost completely inhibited responses to oxymetazoline and clonidine and reduced noradrenaline- and phenylephrine-stimulated responses by about 60%. 5 All the agonists stimulated the uptake of 45Ca into the La3+-resistant Ca2+ fraction of the artery but only noradrenaline and phenylephrine stimulated the efflux of 45Ca into calcium-free solution. The 45Ca uptake stimulated by oxymetazoline and clonidine was abolished by cinnarizine and that stimulated by noradrenaline and phenylephrine was reduced by about 85%. 6 It is concluded that clonidine and oxymetazoline stimulate contractions that are totally dependent on extracellular calcium. Noradrenaline and phenylephrine stimulate contractions that are partly dependent on extracellular calcium and partly dependent on intracellular calcium stores.


Assuntos
Agonistas alfa-Adrenérgicos/farmacologia , Cálcio/metabolismo , Músculo Liso Vascular/efeitos dos fármacos , Animais , Aorta Torácica/efeitos dos fármacos , Radioisótopos de Cálcio , Cinarizina/farmacologia , Feminino , Técnicas In Vitro , Contração Muscular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Cloreto de Potássio/farmacologia , Ratos , Ratos Endogâmicos , Fatores de Tempo
16.
Br J Pharmacol ; 78(3): 449-51, 1983 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-6132638

RESUMO

Disopyramide produces a contraction of the isolated aortic ring of the rat which is graded, develops slowly, and has a time course similar to the tonic phase of the noradrenaline response. This effect is not modified by alpha-adrenoceptor blockade (yohimbine) but is completely abolished by a Ca2+ antagonist (verapamil) or by removal of Ca2+ from the bathing solution. These results indicate that, in the rat aorta, disopyramide has a vasoconstrictor effect dependent on Ca2+ influx across the vascular smooth muscle membrane.


Assuntos
Disopiramida/farmacologia , Músculo Liso Vascular/efeitos dos fármacos , Piridinas/farmacologia , Antagonistas Adrenérgicos alfa/farmacologia , Animais , Aorta/efeitos dos fármacos , Cálcio/fisiologia , Técnicas In Vitro , Masculino , Norepinefrina/farmacologia , Ratos , Ratos Endogâmicos , Verapamil/farmacologia
17.
Urology ; 41(3): 225-30, 1993 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8442302

RESUMO

The causes and treatment of venogenic impotence are still controversial. From September 1989 to April 1991, 317 men complaining of impotence were evaluated in our Erectile Dysfunction Clinic. Seventy patients were suspected of having venous leakage, and all men had dynamic cavernosography performed. Forty-seven of these 70 men (67%) had venous leakage, and a vacuum tumescence device was recommended as initial treatment for all of them. A questionnaire was later mailed to all 47 patients. A response to the questionnaire was obtained from 45 men (96%). Twenty-nine patients had purchased a vacuum tumescence device (Osbon ErecAid). A satisfactory result was obtained in 20 patients (69%) with venous leakage. Since the use of the vacuum tumescence device is relatively safe and noninvasive, and the results are as good as or better than venous ligation, we recommend its use as the initial treatment of venogenic impotence until a consistently reliable treatment for this condition is found.


Assuntos
Disfunção Erétil/etiologia , Disfunção Erétil/reabilitação , Ereção Peniana/fisiologia , Pênis/irrigação sanguínea , Humanos , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Fluxo Sanguíneo Regional/fisiologia , Vácuo
18.
Toxicol Lett ; 87(1): 53-60, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8701445

RESUMO

Organophosphorus pesticides are one of the most commonly used insecticide classes. They act through a potent inhibition of acetylcholinesterase (AChE). Many of them must undergo transformation into the corresponding oxon analogs to inhibit AChE. This study showed that a brain tissue subfraction transformed methyl parathion (O,O-dimethyl O-p-nitrophenyl phosphorothioate) in vitro. Methyl parathion activation was assayed by solvent extraction of the products followed by HPLC and GC-MS analyses and, indirectly, by the inhibition of AChE present in the incubation mixture. The lack of impairment of AChE after 2 h of incubation of the brain subfraction with methyl parathion and, alternatively, with NADPH, CO, SKF 525-A, piperonyl butoxide or nitrogen indicated that this brain subfraction transformed methyl parathion without the involvement of a mixed-function oxidative pathway. The results from HPLC analysis did not show a peak corresponding to methyl paraoxon (O,O-dimethyl O-p-nitrophenylphosphate), but showed the production of an unidentified peak which eluted nearby standard methyl parathion (retention times of 10.65 and 8.86 min, respectively). GC-MS analysis suggested that the unidentified product could be a methyl parathion isomer.


Assuntos
Encéfalo/metabolismo , Inibidores da Colinesterase/metabolismo , Inseticidas/farmacocinética , Metil Paration/farmacocinética , Acetilcolinesterase/análise , Animais , Biotransformação , Cromatografia Gasosa , Cromatografia Líquida de Alta Pressão , Inibidores das Enzimas do Citocromo P-450 , Sistema Enzimático do Citocromo P-450/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Técnicas In Vitro , Espectrometria de Massas , Ratos
19.
Cad Saude Publica ; 14 Suppl 3: 161-72, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9819474

RESUMO

A case study was carried out to explore the occurrence of a cancer cluster in 1992 among young indian adults adults living in an Amazonian village near two 500 kV power transmission lines that began operating a decade ago. Current blood levels of DDT and organophosphorus pesticides and metal levels in hair samples were measured. Extremely low magnetic field exposure was determined during current daily activities carried out by the Indian villagers. Taking into account the cancer incidence rates in different Brazilian cities, the probability of the occurrence of this cluster by chance was considered remote (p< 0.003, Poisson distribution). High blood levels of p,p'-DDT (median levels ranging from 26 to 58 ppb) were observed. As a whole, this community showed a pattern of low exposure to organophosphorus pesticides, and high recent exposure was only observed in a few blood samples. Continuous exposure to extremely low electromagnetic fields originated in the power transmission lines (which reached 95.0 mG under the lines) was observed on several opportunities during daily activities carried out by Indian villagers. Further observational studies should evaluate the interaction between exposure to extremely low electromagnetic fields and prior exposure to tumor initiators in cancer development.


Assuntos
Campos Eletromagnéticos/efeitos adversos , Exposição Ambiental/efeitos adversos , Indígenas Sul-Americanos , Neoplasias/etiologia , Adolescente , Adulto , Brasil/epidemiologia , Análise por Conglomerados , Exposição Ambiental/estatística & dados numéricos , Feminino , Humanos , Incidência , Indígenas Sul-Americanos/estatística & dados numéricos , Masculino , Neoplasias/etnologia , Praguicidas/efeitos adversos , Distribuição de Poisson , População Rural/estatística & dados numéricos , População Urbana/estatística & dados numéricos
20.
Reprod Sci ; 20(8): 990-7, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23314959

RESUMO

The aim of this study was to evaluate whether an in vitro culture (IVC) medium containing either or not ß-mercaptoethanol (BME), bone morphogenetic protein 4 (BMP4), or pregnant mare serum gonadotrophin (PMSG) could be able to promote the development of capuchin monkeys' preantral follicles enclosed in ovarian cortical strips. Follicular viability after IVC was similar to control (89.32%). Primordial follicle recruitment to primary stage was not reached with IVC, but the rate of secondary follicle formation was increased in the medium supplemented with BME, BMP4, and PMSG (44.86%) when compared to IVC control (9.20%). In the medium supplemented with BME, BMP4, and PMSG, contrary to other media, anti-müllerian hormone-messenger RNA (mRNA) expression in ovarian tissue was upregulated (3.4-fold), while that of growth differentiation factor-9 was maintained. The BMP4-mRNA expression, however, appeared downregulated in all cultured tissues. Our findings show a favorable effect of BME, BMP4, and PMSG on the in vitro development of secondary follicles from capuchin monkeys.


Assuntos
Cebus/fisiologia , Técnicas de Maturação in Vitro de Oócitos , Folículo Ovariano/fisiologia , Ovário/fisiologia , Animais , Hormônio Antimülleriano/genética , Hormônio Antimülleriano/metabolismo , Proteína Morfogenética Óssea 4/genética , Proteína Morfogenética Óssea 4/metabolismo , Proteína Morfogenética Óssea 4/farmacologia , Cebus/metabolismo , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Gonadotropinas Equinas/farmacologia , Fator 9 de Diferenciação de Crescimento/genética , Fator 9 de Diferenciação de Crescimento/metabolismo , Técnicas de Maturação in Vitro de Oócitos/métodos , Mercaptoetanol/farmacologia , Folículo Ovariano/metabolismo , Ovário/metabolismo , RNA Mensageiro/metabolismo , Fatores de Tempo , Técnicas de Cultura de Tecidos , Sobrevivência de Tecidos
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