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1.
Chemosphere ; 268: 128858, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33187661

RESUMEN

Heterogeneous photocatalysis was used for the degradation and mineralization of erythromycin (ERY), with a consequent production of carboxylic acids. For that, a series of TiO2 and Ti1-xSnxO2 structured catalysts, namely M1 to M5, was prepared using the washcoating method, with the catalytic coatings being deposited onto stainless steel meshes. Besides, the catalytic activity of the prepared systems was compared to that of the commercial mesh (CM). The results showed that the prepared TiO2 structured catalyst (M1) presented better ERY oxidation than the CM one, what was associated to the higher catalyst load and to the anatase/rutile ratio. Considering the Sn-doped structured catalysts, for M2, M4 and M5 catalysts, lower ERY mineralization and high formation of carboxylic acids were found, when compared to the M3 catalyst. The improved M3 activity was attributed to the formation of a staggered gap (type II heterojunction), providing better charge separation. In this situation, a high generation of hydroxyl radicals is obtained, resulting on a higher ERY mineralization. By the obtained results it is possible to determine that the addition order and the type of Sn compound added in the washcoating process, affects the catalytic activity due to the formation of a solid solution and to the type of produced heterostructures. The M3 catalyst also showed high stability in long-term tests up to 44 h of reaction. The results provide insights into the development of an inexpensive structured catalyst production method and its influence in the stability of the photocatalyst, as well as in its applicability on water/wastewater treatment.


Asunto(s)
Eritromicina , Titanio , Catálisis , Compuestos de Estaño
2.
Cytogenet Genome Res ; 124(2): 151-7, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19420928

RESUMEN

Interspecific hybrids of fish can offer important advances in the zootechnical exploration of this animal group. However, hybrids can pose serious biological risks to the environment and natural populations, making genetic characterization and monitoring of hybrids produced in fish culture important concerns. In the present study, individuals of the hybrid 'Piaupara' were characterized by fluorescence in situ hybridization (FISH) using sex-specific probes to differentiate the respective parental contributions from female Leporinus macrocephalus (Piauçu) and male Leporinus elongatus (Piapara). The application of this technique demonstrated a difference in hybridization patterns between males and females of L. elongatus and L. macrocephalus, mainly due to the fact that the NOR-bearing chromosomes of L. elongatus contain some homology with the probe. This allowed us to detect a clear sex-specific distinction of the hybrid 'Piaupara', demonstrating that this technique is well-suited for the characterization of these hybrids. Moreover, this technique offers an important methodological advance for the study of diverse sex chromosome systems of Leporinus, supplying valuable information about the origin and establishment of a recently described sexual system in this genus.


Asunto(s)
Sondas de ADN/metabolismo , Peces/genética , Hibridación Genética , Secuencias Repetitivas de Ácidos Nucleicos/genética , Cromosomas Sexuales/genética , Clima Tropical , Animales , Femenino , Masculino , Metafase , Región Organizadora del Nucléolo
3.
Braz. j. biol ; 67(4,supl): 805-811, Dec. 2007. ilus, tab
Artículo en Inglés | LILACS | ID: lil-474218

RESUMEN

The Pampas deer (Ozotoceros bezoarticus) is one of the most endangered Neotropical cervid with populations that have been drastically reduced to small and isolated ones, mainly because of its habitat destruction. Random amplified polymorphic DNA (RAPD) markers were used to analyze population divergence and genetic variation within and between two populations corresponding to distinct subspecies. The RAPD markers displayed substantial genetic variation with all animals possessing unique RAPD phenotypes over 105 polymorphic bands produced by 15 primers. An analysis of molecular variance (AMOVA) and a neighbor-joining cluster analysis were performed to assess levels of differentiation between populations. No differentiation was recorded and about 96.0 percent (P < 0.00001) of the total variance was attributable to variation within populations. This result is quite distinct from data obtained by the analysis of the mtDNA control region, and is discussed on the basis of genetic differences between the different markers and the male-biased dispersal patterns generally observed in the mammal species. The data presented herein are potentially useful for future taxonomic and genetic studies in this species, for the monitoring of the genetic variation observed within these populations, and for the development of management guidelines for its conservation.


O Veado-campeiro (Ozotoceros bezoarticus) é uma das espécies de cervídeos neotropical mais ameaçadas devido à destruição de seu hábitat e conseqüente redução e isolamento de suas populações. Marcadores do tipo RAPD (Random amplified polymorphic DNA) foram utilizados na análise da divergência populacional e estimativa da variação genética dentro e entre duas populações correspondentes a diferentes subespécies. Os marcadores RAPD mostraram uma variação genética substancial, sendo que as 105 bandas polimórficas obtidas pelo uso de 15 primers produziram fenótipos únicos para todos os indivíduos analisados. Para avaliar o nível de diferenciação entre as populações, foi realizada uma análise da variância molecular (AMOVA) e uma análise de agrupamento utilizando o método de neighbor-joining. Nenhuma diferenciação foi observada, sendo aproximadamente 96,0 por cento da variação encontrada atribuída à variação dentro das populações estudadas. Este resultado difere do obtido através da análise da região controle do mtDNA, e é discutido levando-se em consideração as diferenças genéticas entre os diferentes marcadores utilizados e o padrão de dispersão geralmente observado nas espécies de mamíferos (realizada principalmente pelos machos). Os dados aqui apresentados poderão ser úteis para futuros estudos taxonômicos e genéticos desta espécie, para o monitoramento da variação genética observada em suas populações e para o desenvolvimento de estratégias de manejo para sua conservação.


Asunto(s)
Animales , Ciervos/genética , Variación Genética , Brasil , ADN Mitocondrial/genética , Técnica del ADN Polimorfo Amplificado Aleatorio
4.
Braz. j. biol ; 67(4)Nov. 2007.
Artículo en Inglés | LILACS-Express | LILACS, VETINDEX | ID: biblio-1467900

RESUMEN

The Pampas deer (Ozotoceros bezoarticus) is one of the most endangered Neotropical cervid with populations that have been drastically reduced to small and isolated ones, mainly because of its habitat destruction. Random amplified polymorphic DNA (RAPD) markers were used to analyze population divergence and genetic variation within and between two populations corresponding to distinct subspecies. The RAPD markers displayed substantial genetic variation with all animals possessing unique RAPD phenotypes over 105 polymorphic bands produced by 15 primers. An analysis of molecular variance (AMOVA) and a neighbor-joining cluster analysis were performed to assess levels of differentiation between populations. No differentiation was recorded and about 96.0% (P 0.00001) of the total variance was attributable to variation within populations. This result is quite distinct from data obtained by the analysis of the mtDNA control region, and is discussed on the basis of genetic differences between the different markers and the male-biased dispersal patterns generally observed in the mammal species. The data presented herein are potentially useful for future taxonomic and genetic studies in this species, for the monitoring of the genetic variation observed within these populations, and for the development of management guidelines for its conservation.


O Veado-campeiro (Ozotoceros bezoarticus) é uma das espécies de cervídeos neotropical mais ameaçadas devido à destruição de seu hábitat e conseqüente redução e isolamento de suas populações. Marcadores do tipo RAPD (Random amplified polymorphic DNA) foram utilizados na análise da divergência populacional e estimativa da variação genética dentro e entre duas populações correspondentes a diferentes subespécies. Os marcadores RAPD mostraram uma variação genética substancial, sendo que as 105 bandas polimórficas obtidas pelo uso de 15 primers produziram fenótipos únicos para todos os indivíduos analisados. Para avaliar o nível de diferenciação entre as populações, foi realizada uma análise da variância molecular (AMOVA) e uma análise de agrupamento utilizando o método de neighbor-joining. Nenhuma diferenciação foi observada, sendo aproximadamente 96,0% da variação encontrada atribuída à variação dentro das populações estudadas. Este resultado difere do obtido através da análise da região controle do mtDNA, e é discutido levando-se em consideração as diferenças genéticas entre os diferentes marcadores utilizados e o padrão de dispersão geralmente observado nas espécies de mamíferos (realizada principalmente pelos machos). Os dados aqui apresentados poderão ser úteis para futuros estudos taxonômicos e genéticos desta espécie, para o monitoramento da variação genética observada em suas populações e para o desenvolvimento de estratégias de manejo para sua conservação.

5.
Braz J Biol ; 67(4 Suppl): 805-11, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18278346

RESUMEN

The Pampas deer (Ozotoceros bezoarticus) is one of the most endangered Neotropical cervid with populations that have been drastically reduced to small and isolated ones, mainly because of its habitat destruction. Random amplified polymorphic DNA (RAPD) markers were used to analyze population divergence and genetic variation within and between two populations corresponding to distinct subspecies. The RAPD markers displayed substantial genetic variation with all animals possessing unique RAPD phenotypes over 105 polymorphic bands produced by 15 primers. An analysis of molecular variance (AMOVA) and a neighbor-joining cluster analysis were performed to assess levels of differentiation between populations. No differentiation was recorded and about 96.0% (P<0.00001) of the total variance was attributable to variation within populations. This result is quite distinct from data obtained by the analysis of the mtDNA control region, and is discussed on the basis of genetic differences between the different markers and the male-biased dispersal patterns generally observed in the mammal species. The data presented herein are potentially useful for future taxonomic and genetic studies in this species, for the monitoring of the genetic variation observed within these populations, and for the development of management guidelines for its conservation.


Asunto(s)
Ciervos/genética , Variación Genética/genética , Animales , Brasil , ADN Mitocondrial/genética , Técnica del ADN Polimorfo Amplificado Aleatorio
6.
Braz. j. vet. res. anim. sci ; 34(2): 85-9, 1997. ilus, tab
Artículo en Inglés | LILACS | ID: lil-246045

RESUMEN

No presente trabalho foi estudado o polimorfismo bioquímico das hemoglobinas de 96 búfalos indianos de diferentes cruzamentos envolvendo as raças Murrah, Jafarabadi e Mediterrâneo, criados na Fazenda Experimental Lageado - UNESP - Botucatu, Estado de Säo Paulo. As variantes de hemoglobinas foram identificadas através de eletroforese em gel de Agar-Amido em sistema de tampäo descontínuo, pH 8,6. Animais portando uma banda rápida (A1) foram considerados AA (4,4 por cento); búfalos com duas bandas (A1 e A2) foram considerados AB (31,87 por cento) quando A2 era mais fraca e BB (31,87 por cento) quando A2 era mais forte. Uma terceira banda foi encontrada, chamada N. Fenótipos com três bandas foram encontrados com as respectivas frequências; ABN (3,3 por cento) e BBN (30,77 por cento). Análises densitométricas e a falta de animais AAN levaram à conclusäo que, de alguma forma, a síntese da cadeia Beta mutante que origina a banda N esteja relacionada provavelmente ao alelo AlfaII. Provavelmente, a alta frequência de animais com banda N seja devida ao uso intenso de poucos reprodutores


Asunto(s)
Animales , Búfalos/sangre , Hemoglobinas Anormales/genética , Polimorfismo Genético , Electroforesis en Gel de Agar/veterinaria
7.
Braz. j. vet. res. anim. sci ; 33(3): 176-80, 1996. ilus, tab
Artículo en Inglés | LILACS | ID: lil-246029

RESUMEN

Foram estudadas as hemoglobinas de 100 éguas da raça Mangalarga, em idade de reproduçäo, provenientes da Fazenda Santa Fé, situada na regiäo de Botucatu. Esses animais foram divididos em 2 grupos, de acordo com o histórico reprodutivo de cada animal, sendo um formado por éguas reprodutivamente normais e o segundo por éguas portadoras de problemas reprodutivos. Foram colhidas amostras de 15 ml de sangue com anticoagulante. As hemoglobinas foram identificadas por meio de eletroforese em gel de poliacrilamida em placa vertical, a 7 por cento em pH 8.6, segundo Davis11 (1964). Quanto ao sistema de hemoglobinas, foram encontrados os seguinte fenótipos para o grupo de éguas reprodutivamente normais: A1--- (2,0 por cento), A1A2m+m+ (21,0 por cento) e A1A2m+m- (27,0 por cento); para o grupo de éguas com problemas reprodutivos: A1--- (10,0 por cento), A1A2m+m+ (12,0 por cento) e A1A2m+m- (28,0 por cento). A diferença na frequência do fenótipo A1--- entre os grupos pode ter ocorrido devido à existência da ligaçäo do loco hemoglobina a outro que controlaria características de produçäo. Além disso, pode estar ocorrendo influência do tipo de clima existente nos trópicos


Asunto(s)
Animales , Femenino , Electroforesis de las Proteínas Sanguíneas/veterinaria , Hemoglobinas/análisis , Caballos/sangre , Reproducción/fisiología
8.
Anat Histol Embryol ; 23(4): 343-51, 1994 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7887486

RESUMEN

The gonads and the germinative cells of 3 male hinnies were studied with light and transmission electron microscopy with the aim to observe the development of germ cells and verify the morphological modifications due to the hybridization. The hinny seminiferous epithelium presented Sertoli cells and spermatogonia with normal features and anomalous spermatocytes I. The other cells from the spermatogenic sequence were not seen. Most of the alterations began to occur in the cytes I, which presented nuclear vacuolization and deposits of amorphous material between the carioteca and the nuclear lamina, forming vesicles, or exaggerated chromatin condensation, resulting in pyknosis. In the cytoplasm vacuolization was also observed, besides organelle destruction. The arrest of meiosis due to lock of chromosome homologies leads to germinative cell degeneration and, therefore, the spermatogenesis arrest. This fact causes a profound alteration in the seminiferous epithelium morphology in comparison with the parental species.


Asunto(s)
Equidae/anatomía & histología , Túbulos Seminíferos/ultraestructura , Animales , Cruzamientos Genéticos , Epitelio/ultraestructura , Hibridación Genética , Masculino , Microscopía Electrónica/veterinaria , Túbulos Seminíferos/citología , Células de Sertoli/citología , Espermatocitos/ultraestructura , Espermatogonias/ultraestructura
9.
Braz J Med Biol Res ; 25(11): 1107-12, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1342590

RESUMEN

Milk serum proteins such as alpha-lactalbumin (ALA) and beta-lactoglobulin (BLG) present biochemical polymorphism which is under the control of codominant autosomal alleles. In the present report, we propose modifications of traditional electrophoretic techniques such as increasing the running gel concentration from 5 to 10% and the addition of 5 M urea to the stacking gel, which permitted the detection of two variants (A and B) at the ALA and BLG loci. About 8 microliters of milk serum (6 mg/ml protein) and 10 microliters of total fresh milk were applied. Bovine serum albumin (BSA) and immunolactoglobulins (ILG) could also be discriminated. Total fresh milk was as useful as the purified serum milk proteins for the discrimination of ALA and BLG serum milk protein polymorphism by alkaline vertical slab polyacrylamide gel electrophoresis. However, BSA and ILG ran with caseins, which prevented their characterization in this system.


Asunto(s)
Electroforesis Discontinua/métodos , Electroforesis en Gel de Poliacrilamida/métodos , Variación Genética , Proteínas de la Leche/análisis , Animales , Bovinos , Femenino , Lactalbúmina/análisis , Lactoglobulinas/análisis , Proteínas de la Leche/genética
10.
Braz. j. med. biol. res ; 25(11): 1107-12, 1992. ilus
Artículo en Inglés | LILACS | ID: lil-134606

RESUMEN

Milk serum proteins such as alpha-lactalbumin (ALA) and beta-lactoglobulin (BLG) present biochemical polymorphism which is under the control of codominant autosomal alleles. In the present report, we propose modifications of traditional electrophoretic techniques such as increasing the running gel concentration from 5 to 10% and the addition of 5 M urea to the stacking gel, which permitted the detection of two variants (A and B) at the ALA and BLG loci. About 8 microliters of milk serum (6 mg/ml protein) and 10 microliters of total fresh milk were applied. Bovine serum albumin (BSA) and immunolactoglobulins (ILG) could also be discriminated. Total fresh milk was as useful as the purified serum milk proteins for the discrimination of ALA and BLG serum milk protein polymorphism by alkaline vertical slab polyacrylamide gel electrophoresis. However, BSA and ILG ran with caseins, which prevented their characterization in this system


Asunto(s)
Animales , Femenino , Electroforesis Discontinua/métodos , Electroforesis en Gel de Poliacrilamida/métodos , Variación Genética , Proteínas de la Leche/análisis , Bovinos , Lactalbúmina/análisis , Lactoglobulinas/análisis , Proteínas de la Leche/genética
11.
J Hered ; 70(1): 67-9, 1979.
Artículo en Inglés | MEDLINE | ID: mdl-469227

RESUMEN

During 1977--78, 715 unmarried college students at the Universidade Estadual Paulista, Botucatu, Brazil, were surveyed for their preferences for family sizes and combinations and permutations of sexes of children. The most preferred family size by both male and female respondents was two children. A slightly lower proportion of respondents preferred a family size of three children. Average size of the desired families was approximately 2.76 children. The most preferred combinations of sexes were one male, one female; one female, two males; and two females, two males, respectively, in families of two, three, and four children. Preferred permutations of sexes were those in which the first child was male and subsequent children resulted in an alternation of sexes.


Asunto(s)
Familia , Brasil , Femenino , Humanos , Masculino , Sexo , Condiciones Sociales , Estudiantes , Encuestas y Cuestionarios
12.
J Hered ; 68(4): 241-4, 1977.
Artículo en Inglés | MEDLINE | ID: mdl-925337

RESUMEN

During 1974--75, data on sex and family size were obtained from approximately 500 Brazilian college students and their parents. Sex ratios for the immediate and parental generations were 107:100 and 106:100, respectively. Correlation coefficients were calculated between sexes of various children in families of the immediate generation. A significant positive relationship was found between sexes of the first two children in families of two or more children. The overall correlation between sexes of successive births was positive but not significant. Correlation coefficients between sexes separated by one or more births were not significant. The observed frequencies of combinations of sexes within the various family sizes did not differ from expected frequencies. Average numbers of children per family were 4.39 and 6.80 for the immediate and parental generations, respectively. Average family sizes decreased as the formal educational level of the parents increased. If the parents' desired both sexes of children, such preferences had no measurable influence on family size.


Asunto(s)
Composición Familiar , Razón de Masculinidad , Brasil , Femenino , Humanos , Italia/etnología , Japón/etnología , Masculino , Portugal/etnología , España/etnología , Estadística como Asunto
13.
Heredity (Edinb) ; 37(2): 295-8, 1976 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-1068114

RESUMEN

Spontaneous recombination in males of Drosophila simulans is reported for the first time. Both second-chromosome and third-chromosome male recombination was observed in lines that had been captured from natural populations.


Asunto(s)
Drosophila , Recombinación Genética , Animales , Cromosomas , Masculino , Factores Sexuales
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