Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
Annu Rev Microbiol ; 74: 455-475, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32905752

RESUMO

Mosquito-transmitted diseases, including malaria and dengue, are a major threat to human health around the globe, affecting millions each year. A diverse array of next-generation tools has been designed to eliminate mosquito populations or to replace them with mosquitoes that are less capable of transmitting key pathogens. Many of these new approaches have been built on recent advances in CRISPR/Cas9-based genome editing. These initiatives have driven the development of pathogen-resistant lines, new genetics-based sexing methods, and new methods of driving desirable genetic traits into mosquito populations. Many other emerging tools involve microorganisms, including two strategies involving Wolbachia that are achieving great success in the field. At the same time, other mosquito-associated bacteria, fungi, and even viruses represent untapped sources of new mosquitocidal or antipathogen compounds. Although there are still hurdles to be overcome, the prospect that such approaches will reduce the impact of these diseases is highly encouraging.


Assuntos
Agentes de Controle Biológico , Controle de Doenças Transmissíveis , Doenças Transmissíveis/parasitologia , Doenças Transmissíveis/virologia , Culicidae/genética , Controle de Mosquitos/métodos , Animais , Doenças Transmissíveis/transmissão , Culicidae/parasitologia , Culicidae/fisiologia , Culicidae/virologia , Humanos , Infertilidade , Malária , Wolbachia/genética
2.
Am J Hum Biol ; 13(5): 660-7, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11505474

RESUMO

New data on 17 blood group and protein genetic systems obtained among the Ayoreo and Lengua Indians of Paraguay are presented. They include the first report on the red cell band-3 protein investigated among South American Indians. This information was integrated with previous results available for these two and four other groups. Five of the six populations reside in the Chaco area, while the sixth was included as an outgroup living elsewhere in Paraguay. Four of the five Chaco tribes exhibit good genetic homogeneity, but the Ayoreo are somewhat different. The results confirm the Chaco as a distinct biological (as well as cultural and economic) region, which should be considered in evaluations of genetic variability among South American Indians.


Assuntos
Antígenos de Grupos Sanguíneos/genética , Proteínas Sanguíneas/genética , Variação Genética , Indígenas Sul-Americanos , Alelos , Distribuição de Qui-Quadrado , Frequência do Gene , Haplótipos , Humanos , Método de Monte Carlo , Paraguai , Fenótipo , Polimorfismo Genético
3.
Hernia ; 5(2): 59-64, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11505649

RESUMO

Two types of monofilament polypropylene meshes of markedly different construction, configuration and pore size were compared and used to repair full-thickness muscle defects in the abdominal wall of 22 mongrel dogs to assess their biocompatibility with host tissues. The defects were repaired with Prolene (Ethicon) woven mesh (pore size = 164 x 96 microns) and with an experimental, extruded mesh called T mesh (pore size = 3 mm x 4 mm). On the 30th postoperative day, the animals were sacrificed, and the segments of the abdominal wall containing the implanted meshes were excised. Although the Prolene mesh had greater tensile strength before implantation, 30 days after implantation, the T mesh showed similar tensile strength to Prolene mesh. The collagen densitometry showed a significant increase of total and mature collagen type I deposition in the T mesh. This suggests that the increased mature collagen type I deposition significantly increases the tensile strength of the reinforced mesh tissue and that the larger pore in the T mesh contributed to this finding by allowing increasing fibber orientation within the pores as a result of in vivo tension.


Assuntos
Músculos Abdominais/lesões , Músculos Abdominais/cirurgia , Materiais Biocompatíveis , Polipropilenos , Telas Cirúrgicas , Animais , Cães , Procedimentos de Cirurgia Plástica , Propriedades de Superfície
4.
Am J Phys Anthropol ; 115(2): 133-43, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11385600

RESUMO

A total of 495 individuals from five different Argentinian tribes was examined for variation in 23 blood group and protein genetic systems, and the results were integrated with previous data on some of these systems. These tribes generally present RH * R1, PGM1 * 1, and ACP * A frequencies lower and RH * R2, ESD * 1, and GLO * 1 prevalences higher than those observed in other South American Indian groups. Earlier studies with mitochondrial DNA showed that haplogroup A was present in low frequencies in these tribes, but haplogroup B showed a high prevalence among the Mataco. Average heterozygosities are very similar in the five tribes, while estimates of non-Indian ancestry are generally low. Both the blood group and protein, as well as the mtDNA data sets, divide the five tribes into two groups, and the relationships obtained with the blood group and protein systems are exactly those expected on the basis of geography and language. However, the topology obtained with the mtDNA results was different, possibly due to sampling effects or diverse patterns of exchange between the groups related to sex.


Assuntos
DNA Mitocondrial/genética , Frequência do Gene , Indígenas Norte-Americanos/genética , Argentina , Teste de Histocompatibilidade , Humanos , Proteínas/genética
5.
J. bras. ginecol ; 106(11/12): 435-8, nov.-dez. 1996. tab, graf
Artigo em Português | LILACS | ID: lil-189014

RESUMO

Com o objetivo de acompanhar os efeitos da sulpiride, droga neuroléptica derivada das benzaminas de açäo hiperprolactinêmica por bloqueio dos receptores da dopamina, nas mamas, no útero e nos ovários de ratas virgens. Utilizaram-se 40 ratas Wistar, virgens, com idade entre 70 a 100 dias e peso variando de 224 a 299 g aleatoriamente divididas em dois grupos de 20 ratas, SF e MED. Às ratas do grupo MED administrou-se 10 mg/100g de peso de sulpiride por sondagem orogástrica, diarimente e ao grupo SF, soluçäo fisiológica em igual volume. Cinco animais de cada grupo foram sorteados para sacrifício nos 7§, 14§, 21§ e 42§ dias após o início do tratamento. Ressecava-se 1 cm² de pele e tela subcutânea contendo o mamilo inguinal direito e por laparotomia, o útero e os ovários. No estudo histopatológico avaliava-se nas mamas: concentraçäo de alvélos por campo, o diâmetro dos ductos e a presença ou ausência de secreçäo no interior dos mesmos. No útero observa-se: a fase do endométrio e a sua espessura. As medidas foram feitas com ocular milimetrada. Nos ovários, verificava-se a predominância de folículos e a presença de corpos lúteos. Cinco animais foram excluídos do experimento. O estudo histológico das mamas mostrou aumento do número de folículos por campo à partir do 14§ dia (p<0,05). Estes mostrava-se dilatados em todos os tempos observados (p<0,05). Secreçäo esteve presente a partir do 14§ dia e em grande quantidade (p14=0,0397, p21=0,0079, p42=0,0397). Todos os endométrios do SF encontravam-se em fase proliferativa. No grupo MED cinco endométrios estavam em fase secretora e 14 em fase proliferativa. Näo se observou diferença significante quanto a espessura do endométrio. Os ovários exibiam folículos em diferentes fases de desenvolvimento e näo havia diferença entre os grupos. Conclui-se que a sulpiride atua sobre as glândulas mamárias de ratas estimulando seu desenvolvimento e galactogênese, sendo diretamente proporcional ao tempo de uso. Näo se observou influência sobre o endométrio e os ovários


Assuntos
Animais , Feminino , Ratos , Mama/efeitos dos fármacos , Hiperprolactinemia/induzido quimicamente , Ovário/efeitos dos fármacos , Sulpirida/farmacologia , Útero
6.
Gene Geogr ; 6(1-2): 17-20, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1299310

RESUMO

Limited proteolysis of intact red cells has been shown to yield peptides of 60 kDa and, in some individuals, 63 kDa, from the band-3 membrane protein. In a random population sample of 117 Brazilians of Japanese origin, the allele frequencies of the band-3 variants were p60 = 0.889 +/- 0.0205 and p63 = 0.111 +/- 0.0205. The phenotype frequencies fit the Hardy-Weinberg equilibrium for the hypothesis of three phenotypes controlled by two codominant alleles of a single autosomal locus. The frequencies of the alleles in this population of Japanese ancestry are highly different from those of Brazilian Caucasoid blood donors but rather similar to those of Brazilian Negroid donors.


Assuntos
Proteína 1 de Troca de Ânion do Eritrócito/genética , Povo Asiático/genética , Etnicidade/genética , Frequência do Gene , Adoção , Adulto , Alelos , População Negra/genética , Brasil , China/etnologia , Consanguinidade , Feminino , Marcadores Genéticos , Genótipo , Hong Kong/etnologia , Humanos , Japão/etnologia , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético , Taiwan/etnologia , População Branca/genética
7.
Hum Genet ; 86(2): 126-30, 1990 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2265824

RESUMO

Three phenotypes based on the polymorphism of band-3 protein from human red cells are described. Limited proteolysis of intact red cells from most individuals (homozygotes) yields a peptide of 60 kDa, but in some cases (heterozygotes), there is also a 63-kDa peptide, and rarely only the single peptide of 63 kDa is found. This is the first description of the 63-kDa homozygote. The interpretation that the three phenotypes are controlled by two alleles of a single autosomal locus, with no dominance, is supported by population and family studies. The frequencies of the allele, which we designate as p63, is 0.041 +/- 0.0068 in Caucasoids and 0.125 +/- 0.0121 in Negroids. The electrophoretic profiles and molecular weights of the peptides obtained with several commercial proteases from Streptomyces griseus are similar to those obtained with chymotrypsin. Whereas band-3 protein in two New-World monkeys (Saimiri and Cebus) resisted pronase attack, an Old-World monkey (Macaca mulatta) was monomorphic for a 63-kDa fragment, and in an ape (Pan troglodytes), a doublet of 62 kDa and 64 kDa was found. Band-3 protein polymorphism appears to be a good marker for genetic differentiation in human populations.


Assuntos
Proteína 1 de Troca de Ânion do Eritrócito/genética , Hominidae/genética , Peptídeos/sangue , Primatas/genética , Animais , Evolução Biológica , Endopeptidases , Membrana Eritrocítica/química , Hominidae/sangue , Humanos , Hidrólise , Peso Molecular , Peptídeos/genética , Primatas/sangue
11.
Talanta ; 28(4): 237-40, 1981 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18962906

RESUMO

Potentiometry with ion-selective electrodes and anodic stripping voltammetry were used to measure the stability constants for cadmium chloro-complexes at 20 +/- 0.1 degrees in synthetic sea-water and at an ionic strength of 0.700 (NaClO(4) + NaCl). The values of beta(ML) and beta(ML(2)) obtained by the two methods are in good agreement.

12.
Talanta ; 15(7): 609-22, 1968 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18960344

RESUMO

The uranyl complexes of EDTA have been studied by potentiometry ; stability constants of the 1:1 and 2:1 (metal to ligand) chelates have been determined, as well as the respective hydrolysis and polymerization constants. Possible structures for these species are discussed. To account for the abnormally high stability of UO(2)(H(2)O)HL-, hydrogen bonding between a protonated nitrogen atom of the ligand and one oxygen atom of UO(2)(2+) is suggested.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...