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1.
Genet Mol Res ; 10(3): 2223-9, 2011 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-21968729

RESUMO

We developed 12 microsatellite loci for the endangered minnow species, Tanichthys albonubes, using PCR-based isolation of microsatellite arrays. These new markers were tested in 26 individuals from a wild population collected from Guangzhou in China and 26 individuals from a cultured strain. The number of alleles ranged from two to nine and the expected heterozygosity from 0.177 to 0.853. The wild population had significantly higher allelic richness than the cultured strain, with a mean allelic richness of 5.52 (range = 3.69-8.64) and 3.13 (range = 1.99-5.73) for the wild population and the cultured strain, respectively. No evidence of a recent bottleneck was detected in the wild population, but it was found in the cultured strain based on the BOTTLENECK test. These primers can be used to understand the demography and to examine genetic differences between the cultured T. albonubes strains and wild populations to help determine conservation and reintroduction strategies.


Assuntos
Cyprinidae/genética , Repetições de Microssatélites , Alelos , Animais , Sequência de Bases , Primers do DNA/genética , Espécies em Perigo de Extinção , Marcadores Genéticos , Variação Genética , Técnica de Amplificação ao Acaso de DNA Polimórfico , Análise de Sequência de DNA
2.
Appl Opt ; 15(6): 1411-7, 1976 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-20165199

RESUMO

Polarization Reference Imaging (PRIM) systems utilize the polarized and coherent output characteristics of lasers to eliminate turbulence and/or optical figure errors. Computer simulation studies of the PRIM system are presented. The simulation scheme, PRIM reconstructed images, and their image quality dependence on system parameters are shown and discussed.

3.
Appl Opt ; 12(9): 2050-3, 1973 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-20125666

RESUMO

An equivalent network representation is derived for a rectangular corrugation profile grating that has been shown recently to exhibit surprisingly large blaze effect. Under proper conditions, up to 100% power conversion takes place between the incident wave and a single diffracted spectral order. The results herein show that this blaze effect can be attributed to a half-wavelength resonance in the corrugation region. Based on the equivalent network representation, a design procedure has been derived that yields the grating profile parameters (d, h) necessary to achieve the 100% conversion effect.

4.
J Biomed Mater Res ; 42(2): 188-98, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9773815

RESUMO

We sought to examine whether surface modification of expanded polytetrafluoroethylene (ePTFE) vascular grafts might extend graft patency without modifying the graft structure. Amide and amine plasma (butylamine) were applied to graft surfaces using radio frequency glow discharge. Surface analyses by Fourier transform infrared spectroscopy-attenuated total reflectance, X-ray photoelectron spectroscopy, and dynamic contact angle measurements revealed the presence of nitrogen-containing functional groups on the plasma modified graft surfaces, along with an increased surface hydrophilicity. Bovine aortic endothelial cells were seeded on amide and amine plasma coated ePTFE vascular grafts and placed inside an artificial circulatory system under well-defined flow conditions. The seeded endothelial cells were exposed to either constant or pulsatile flow condition for 5 days. Their corresponding maximum wall shear stresses were 1 dyn/cm2 under constant flow and 65, 108, and 259 dyn/cm2 under various pulsatile flows. Plasma modified ePTFE vascular grafts enhanced the endothelial cell lining under constant and pulsatile flow conditions. Fluorescence nuclear staining, scanning electron microscopy, and histological staining indicated the formation of an endothelial cell monolayer on the plasma coated graft surfaces.


Assuntos
Amidas , Materiais Biocompatíveis , Bioprótese , Vasos Sanguíneos , Politetrafluoretileno , Animais , Bovinos , Endotélio Vascular , Circulação Extracorpórea/instrumentação , Circulação Extracorpórea/métodos
5.
Biotechnol Bioeng ; 52(6): 661-71, 1996 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-18629945

RESUMO

The degradation of organic matter was evaluated by a quantitative Fourier transform infrared spectroscopy (FTIR) analysis technique. The degradation process was conducted in a bench-scale reactor under controlled operational conditions of 50 degrees C, with 50-60% moisture content, and subjected to uniform aeration for 325 h. During the composting process, ATP concentration increased from 0.1 to 8 mug/g and the maximum CO(2) evolution and O(2) consumption rates reached 0.04 and 0.085 mmol/g-h, respectively. Polysaccharide content decreased approximately 50% while lignin content remained unchanged. Three regions of the FTIR spectra were used for quantification: 1070-974, 1705-1614, and 2995-2887 cm(-1), which correspond to polysaccharides and aromatic and aliphatic compounds, respectively. The actual spectra quantification consisted of peak identification using a second derivative and curve fitting technique, followed by normalization using the internal standard CaCO(3). The results obtained with the spectra quantification technique was then compared to commonly used wet chemistry extraction procedures. Reasonable correlation between the two techniques was obtained. (c) 1996 John Wiley & Sons, Inc.

6.
Mol Reprod Dev ; 54(3): 215-22, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10497343

RESUMO

Vitellogenesis is an important part of reproductive process in crustaceans, and the process is characterized by the synthesis and accumulation of yolk protein in the developing oocytes. The yolk proteins in crustaceans mainly consist of vitellogenin (Vg) and vitellin (Vn), which are respectively present in extra-oocyte tissues and intra-oocytes. The site and the process of yolk protein synthesis in crustaceans are still controversial. The synthesis site of Vg in a crustacean species, Macrobrachium rosenbergii, is determined by immunological and immunohistochemical techniques, and molecular cloning of a cDNA encoding the primary structure of Vn in this study. The hepatopancrease is clearly shown to be the synthesis site of Vg in this species. The length of Vg mRNA was estimated as about 6 kb from Northern blotting analysis. The partial primary structure of Vg gene is presented, and the post-translational processing are further discussed. For the first time, the partial primary structure of Vg gene and the synthesis site of Vg approached by molecular cloning in crustaceans are presented.


Assuntos
DNA Complementar/análise , Palaemonidae/genética , Vitelogeninas/biossíntese , Sequência de Aminoácidos , Animais , Sequência de Bases , Northern Blotting , Sistema Digestório/metabolismo , Proteínas do Ovo/genética , Feminino , Imuno-Histoquímica , Masculino , Dados de Sequência Molecular , Palaemonidae/anatomia & histologia , Testes de Precipitina , RNA Mensageiro/análise , Vitelogeninas/análise , Vitelogeninas/metabolismo
7.
Circ Res ; 84(4): 378-83, 1999 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-10066671

RESUMO

Endovascular stents expand the arterial lumen more than balloon angioplasty and reduce rates of restenosis after coronary angioplasty in selected patients. Understanding the factors involved in vascular injury imposed during stent deployment may allow optimization of stent design and stent-placement protocols so as to limit vascular injury and perhaps reduce restenosis. Addressing the hypothesis that a previously undescribed mechanism of vascular injury during stent deployment is balloon-artery interaction, we have used finite element analysis to model how balloon-artery contact stress and area depend on stent-strut geometry, balloon compliance, and inflation pressure. We also examined superficial injury during deployment of stents of varied design in vivo and in a phantom model ex vivo to show that balloon-induced damage can be modulated by altering stent design. Our results show that higher inflation pressures, wider stent-strut openings, and more compliant balloon materials cause markedly larger surface-contact areas and contact stresses between stent struts. Appreciating that the contact stress and contact area are functions of placement pressure, stent geometry, and balloon compliance may help direct development of novel stent designs and stent-deployment protocols so as to minimize vascular injury during stenting and perhaps to optimize long-term outcomes.


Assuntos
Artérias/patologia , Cateterismo/efeitos adversos , Stents/efeitos adversos , Animais , Artérias/fisiopatologia , Complacência (Medida de Distensibilidade) , Endotélio Vascular/patologia , Desenho de Equipamento , Análise de Elementos Finitos , Inflação , Pressão , Coelhos
8.
Artigo em Inglês | MEDLINE | ID: mdl-11440876

RESUMO

The site of yolk protein synthesis in crustaceans has long been a subject of controversy. The vitellogenin gene structure was partially reported only very recently in Macrobrachium rosenbergii, after which the hepatopancreas was confirmed as the extraovarian site of vitellogenin synthesis in that species. Ovaries are the most frequently reported as the site of yolk protein synthesis in penaeid shrimp. Using cDNA reversed-transcribed from mRNA isolated from the hepatopancreas of vitellogenic female shrimp, Penaeus monodon, we found that its deduced amino acid sequence had high identity of 48% with that from M. rosenbergii vitellogenin. A similar location of the intron in the sequenced region of genomic DNA was also found between these two species. We therefore concluded that the hepatopancreas the extraovarian site of vitellogenin synthesis in P. monodon in vivo. The partial structure of vitellogenin gene is presented in this study.


Assuntos
Sistema Digestório/metabolismo , Penaeidae/metabolismo , Vitelogeninas/biossíntese , Sequência de Aminoácidos , Animais , Sequência de Bases , DNA Complementar , Feminino , Dados de Sequência Molecular , Ovário/metabolismo , Penaeidae/genética , Reação em Cadeia da Polimerase , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Alinhamento de Sequência , Vitelogeninas/química , Vitelogeninas/genética
9.
Appl Opt ; 11(12): 2998-3000, 1972 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-20119455
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