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Effects of a single nucleotide polymorphism in the leptin gene on the productive traits of dairy buffaloes (Bubalus bubalis)

Zetouni, Larissa; De Camargo, Gregório Miguel Ferreira; Da Silva Fonseca, Patrícia Dias; Gil, Fernanda Maria Monsalves; Lugo, Naudin Alejandro Hurtado; Aspilcueta-Borquis, Rusbel Raul; Cervini, Marcelo; Tonhati, Humberto
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 5159-5163
ENG
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The gene responsible for coding the leptin hormone has been associated with productive and reproductive traits in cattle. In dairy cattle, different polymorphisms found in the leptin gene have been associated with several traits of economic interest, such as energy balance, milk yield and composition, live weight, fertility and dry matter consumption. The aim of this study was to detect genetic variability in the leptin gene of buffaloes and to test possible associations with milk yield, fat and protein percentages, age at first calving and first calving interval. Three genotypes (AA, AG and GG) were identified by polymerase chain reaction-restriction fragment length polymorphism, which presented genotypic frequencies of 0.30, 0.54 and 0.16, respectively. The allele frequencies were 0.57 for the A allele and 0.43 for the G allele. No significant effects were found in the present study, but there is an indicative that leptin gene affects lipid metabolism. © 2013 Springer Science+Business Media Dordrecht.

Molecular identification of similar species of the genus Biomphalaria (Mollusca: Planorbidae) determined by a polymerase chain reaction-restriction fragment length polymorphism

Caldeira,Roberta Lima; Vidigal,Teofânia HDA; Paulinelli,Sônia Torquato; Simpson,Andrew JG; Carvalho,Omar S
Fonte: Instituto Oswaldo Cruz, Ministério da Saúde Publicador: Instituto Oswaldo Cruz, Ministério da Saúde
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/1998 EN
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126.2%
The freshwater snails Biomphalaria straminea, B. intermedia, B. kuhniana and B. peregrina, are morphologically similar; based on this similarity the first three species were therefore grouped in the complex B. straminea. The morphological identification of these species is based on characters such as vaginal wrinkling, relation between prepuce: penial sheath:deferens vas and number of muscle layers in the penis wall. In this study the polymerase chain reaction restriction fragment length polymorphism technique was used for molecular identification of these molluscs. This technique is based on the amplification of the internal transcribed spacer regions ITS1 e ITS2 of the ribosomal RNA gene and subsequent digestion of these fragments by restriction enzymes. Six enzymes were tested: Dde I, Mnl I, Hae III, Rsa I, Hpa II e Alu I. The restriction patterns obtained with DdeI presented the best profile for separation of the four species of Biomphalaria. The profiles obtained with all the enzymes were used to estimate the genetic distances among the species through analysis of common banding patterns.

Morphological and polymerase chain reaction-restriction fragment lenght polymorphism characterization of Biomphalaria kuhniana and Biomphalaria amazonica from Colombia

Velásquez,Luz E; Caldeira,Roberta L; Estrada,Victoria; Carvalho,Omar S
Fonte: Instituto Oswaldo Cruz, Ministério da Saúde Publicador: Instituto Oswaldo Cruz, Ministério da Saúde
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/10/2002 EN
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106.12%
In Colombia, five Biomphalaria planorbid species are known: B. kuhniana, B. straminea, B. peregrina, B. canonica and B. oligoza(var. B. philippiana). Among them, B. straminea is intermediate host of Schistosoma mansoni and B. peregrina has been found to be experimentally susceptible to this parasite. B. straminea is commonly confused with B. kuhniana and they have been clustered together with B. intermedia in the complex named B. straminea. The difficulties involved in the specific identification, based on morphological data, have motivated the use of new techniques as auxiliary tools in cases of inconclusive morphological identification of such planorbid. In the present study, five Biomphalaria populations from the Colombian Amazon region and from Interandian Valleys were morphologically identified and characterized by polymerase chain reaction-restriction fragment lenght polymorphism directed at the internal transcribed spacer region of the rRNA gene, followed by digestion of the generated fragment with restriction enzymes (DdeI, AluI, RsaI, MvaI and HaeIII). Known profiles of the Brazilian species B. straminea, B. peregrina, B. kuhniana, B. intermedia and B. amazonica, besides B. kuhniana from Colombia, were used for comparison. The five populations under study were morphologically and molecularly identified as B. kuhniana and B. amazonica.

Polymerase chain reaction and restriction fragment length polymorphism of cytocrome oxidase subunit I used for differentiation of Brazilian Biomphalaria species intermediate host of Schistosoma mansoni

Vidigal,Teofânia HDA; Montresor,Lângia C; Simpson,Andrew JG; Carvalho,Omar S
Fonte: Instituto Oswaldo Cruz, Ministério da Saúde Publicador: Instituto Oswaldo Cruz, Ministério da Saúde
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/10/2002 EN
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126.16%
The intermediate hosts of Schistosoma mansoni, in Brazil, Biomphalaria glabrata, B. tenagophila and B. straminea, were identified by restriction fragment length polymorphism analysis of the mitochondrial gene cytochrome oxidase I (COI). We performed digestions with two enzymes (AluI and RsaI), previously selected, based on sequences available in Genbank. The profiles obtained with RsaI showed to be the most informative once they were polymorphic patterns, corroborating with much morphological data. In addition, we performed COI digestion of B. straminea snails from Uruguay and Argentina.

Molecular differentiation of Angiostrongylus costaricensis, A. cantonensis, and A. vasorum by polymerase chain reaction- restriction fragment length polymorphism

Caldeira,Roberta L; Carvalho,Omar S; Mendonça,Cristiane LFG; Graeff-Teixeira,Carlos; Silva,Márcia CF; Ben,Renata; Maurer,Rafael; Lima,Walter S; Lenzi,Henrique L
Fonte: Instituto Oswaldo Cruz, Ministério da Saúde Publicador: Instituto Oswaldo Cruz, Ministério da Saúde
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2003 EN
Relevância na Pesquisa
126.18%
Angiostrongylus cantonensis, A. costaricensis, and A. vasorum are etiologic agents of human parasitic diseases. Their identification, at present, is only possible by examining the adult worm after a 40-day period following infection of vertebrate hosts with the third-stage larvae. In order to obtain a diagnostic tool to differentiate larvae and adult worm from the three referred species, polymerase chain reaction-restriction fragment length polymorphism was carried out. The rDNA second internal transcribed spacer (ITS2) and mtDNA cytochrome oxidase I regions were amplified, followed by digestion of fragments with the restriction enzymes RsaI, HapII, AluI, HaeIII, DdeI and ClaI. The enzymes RsaI and ClaI exhibited the most discriminating profiles for the differentiation of the regions COI of mtDNA and ITS2 of rDNA respectively. The methodology using such regions proved to be efficient for the specific differentiation of the three species of Angiostrongylus under study.

The use of the polymerase chain reaction and restriction fragment length polymorphism technique associated with the classical morphology for characterization of Lymnaea columella, L. viatrix, and L. diaphana (Mollusca: Lymnaeidae)

Carvalho,Omar S; Cardoso,Paula CM; Lira,Pollanah M; Rumi,Alejandra; Roche,Andrea; Berne,Elizabeth; Müller,Gertrud; Caldeira,Roberta L
Fonte: Instituto Oswaldo Cruz, Ministério da Saúde Publicador: Instituto Oswaldo Cruz, Ministério da Saúde
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2004 EN
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116.16%
The specific identification of Lymnaeid snails is based on a comparison of morphological characters of the shell, radula, renal and reproductive organs. However, the identification is complicated by dissection process, intra and interspecific similarity and variability of morphological characters. In the present study, polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) techniques targeted to the first and second internal transcribed spacers (ITS1 and ITS2) rDNA and to the mitochondrial 16S ribosomal gene (16S rDNAmt) were used to differentiate the species Lymnaea columella, L. viatrix, and L. diaphana from some localities of Brazil, Argentina, and Uruguay as well as to verify whether the molecular results corroborates the classical morphological method.PCR-RFLP analysis of the ITS1, ITS2, and 16S using 12 restriction enzymes revealed characteristic patterns for L. columella and L. diaphana which were concordant with the classical morphology. On the other hand, for L. viatrix populations a number of 1 to 6 profiles were generated while morphology provided the species pattern results.

Mycobacterium tuberculosis complex differentiation using gyrB-restriction fragment length polymorphism analysis

Chimara,Erica; Ferrazoli,Lucilaine; Leão,Sylvia Cardoso
Fonte: Instituto Oswaldo Cruz, Ministério da Saúde Publicador: Instituto Oswaldo Cruz, Ministério da Saúde
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/11/2004 EN
Relevância na Pesquisa
126.18%
Mycobacterium tuberculosis complex (MTBC) members are causative agents of human and animal tuberculosis. Differentiation of MTBC members is required for appropriate treatment of individual patients and for epidemiological purposes. Strains from six MTBC species - M. tuberculosis, M. bovis subsp. bovis, M. bovis BCG, M. africanum, M. pinnipedii, and "M. canetti" - were studied using gyrB-restriction fragment length polymorphism (gyrB-RFLP) analysis. A table was elaborated, based on observed restriction patterns and published gyrB sequences. To evaluate applicability of gyrB-RFLP at Instituto Adolfo Lutz, São Paulo, Mycobacterial Reference Laboratory, 311 MTBC clinical isolates, previously identified using traditional methods as M. tuberculosis (306), M. bovis (3), and M. bovis BCG (2), were analyzed by gyrB-RFLP. All isolates were correctly identified by the molecular method, but no distinction between M. bovis and M. bovis BCG was obtained. Differentiation of M. tuberculosis and M. bovis is of utmost importance, because they require different treatment schedules. In conclusion, gyrB-RFLP is accurate and easy-to-perform, with potential to reduce time needed for conventional differentiation methods. However, application for epidemiological studies remains limited...

Mycobacterium avium restriction fragment lenght polymorphism-IS IS1245 and the simple double repetitive element polymerase chain reaction typing method to screen genetic diversity in Brazilian strains

Sequeira,Patrícia Carvalho de; Fonseca,Leila de Souza; Silva,Marlei Gomes da; Saad,Maria Helena Féres
Fonte: Instituto Oswaldo Cruz, Ministério da Saúde Publicador: Instituto Oswaldo Cruz, Ministério da Saúde
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/11/2005 EN
Relevância na Pesquisa
116.13%
Simple double repetitive element polymerase chain reaction (MaDRE-PCR) and Pvu II-IS1245 restriction fragment length polymorphism (RFLP) typing methods were used to type 41 Mycobacterium avium isolates obtained from 14 Aids inpatients and 10 environment and animals specimens identified among 53 mycobacteria isolated from 237 food, chicken, and pig. All environmental and animals strains showed orphan patterns by both methods. By MaDRE-PCR four patients, with multiple isolates, showed different patterns, suggesting polyclonal infection that was confirmed by RFLP in two of them. This first evaluation of MaDRE-PCR on Brazilian M. avium strains demonstrated that the method seems to be useful as simple and less expensive typing method for screening genetic diversity in M. avium strains on selected epidemiological studies, although with limitation on analysis identical patterns except for one band.

IS6110 restriction fragment length polymorphism typing of Mycobacterium tuberculosis isolates from East Azerbaijan Province of Iran

Asgharzadeh,Mohamad; Shahbabian,Karen; Majidi,Jafar; Aghazadeh,Ahmad Mirza; Amini,Cirus; Jahantabi,Ali Reza; Rafi,Abdolnaser
Fonte: Instituto Oswaldo Cruz, Ministério da Saúde Publicador: Instituto Oswaldo Cruz, Ministério da Saúde
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2006 EN
Relevância na Pesquisa
126.18%
To investigate the genetic variation among Mycobacterium tuberculosis isolates in the East Azerbaijan Province of Iran and to evaluate the level of and risk factors for recent transmission of tuberculosis (TB), we performed IS6110-based restriction fragment length polymorphism analysis of strains, isolated from 105 patients during the period of September 2002 to March 2003 in TB centers and university hospitals of the province. Among 105 isolates, 81 different IS6110 patterns were found, of which 70 were observed only once and 11 were shared by two to eight isolates. Ninety-six isolates (91.4%) were found to have more than five copies of IS6110 and together with high patterns polymorphism, shows that IS6110-RFLP typing could be useful for studying the epidemiology of TB in Azerbaijan. The minimum estimated rate of recent transmission was 23%, suggesting that the degree of recent transmission in East Azerbaijan Province is relatively low. Clustering was not associated with age, sex or site of infection of TB but drug-resistant isolates were less likely to be clustered than sensitive isolates (p < 0.05).

Characterization of six rat strains (Rattus norvegicus) by mitochondrial DNA restriction fragment length polymorphism

Hilsdorf,A.W.; Krieger,J.E.
Fonte: Associação Brasileira de Divulgação Científica Publicador: Associação Brasileira de Divulgação Científica
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/1999 EN
Relevância na Pesquisa
126.21%
Restriction fragment length polymorphism (RFLP) was used to examine the extent of mtDNA polymorphism among six strains of rats (Rattus norvegicus) - Wistar, Wistar Munich, Brown Norway, Wistar Kyoto, SHR and SHR-SP. A survey of 26 restriction enzymes has revealed a low level of genetic divergence among strains. The sites of cleavage by EcoRI, NcoI and XmnI were shown to be polymorphic. The use of these three enzymes allows the 6 strains to be classified into 4 haplotypes and identifies specific markers for each one. The percentage of sequence divergence among all pairs of haplotypes ranged from 0.035 to 0.33%, which is the result of a severe population constriction undergone by the strains. These haplotypes are easily demonstrable and therefore RFLP analysis can be employed for genetic monitoring of rats within animal facilities or among different laboratories.

Quantitative analysis of Terminal Restriction Fragment Length Polymorphism (T-RFLP) microbial community profiles: peak height data showed to be more reproducible than peak area

Caffaro-Filho,Roberto A.; Fantinatti-Garboggini,Fabiana; Durrant,Lucia R.
Fonte: Sociedade Brasileira de Microbiologia Publicador: Sociedade Brasileira de Microbiologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2007 EN
Relevância na Pesquisa
126.16%
Terminal Restriction Fragment Length Polymorphism (T-RFLP) is a culture-independent fingerprinting method for microbial community analysis. Profiles generated by an automated electrophoresis system can be analysed quantitatively using either peak height or peak area data. Statistical testing demontrated that peak height data showed to be more reproducible than peak area data.

A simple and reliable PCR-restriction fragment length polymorphism assay to identify Candida albicans and its closely related Candida dubliniensis

Ge,Yi Ping; Wang,Le; Lu,Gui Xia; Shen,Yong Nian; Liu,Wei Da
Fonte: Sociedade Brasileira de Microbiologia Publicador: Sociedade Brasileira de Microbiologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2012 EN
Relevância na Pesquisa
126.16%
Candida dubliniensis is an emerging pathogen capable of causing superficial as well as systemic infections. Due to its close similarity to C. albcians, conventional methods based on phenotypic traits are not always reliable in identification of C. dubliniensis. In this study, we developed a PCR-restriction fragment length polymorphism (RFLP) assay to identify and discriminate between the two closely related species. The D1/D2 region of 28S rDNA was amplified by PCR and enzymatically digested by ApaI and BsiEI respectively. PCR products of both species were digested into two fragments by ApaI, but those of other yeast species were undigested. BsiEI cut the PCR products of C. albicans into two fragments but not those of C. dubliniensis. Thus two species were differentiated. We evaluated 10 reference strains representing 10 yeast species, among which C. albicans and C. dubliniensis were successfully identified. A total of 56 phenotypically characterized clinical isolates (42 C. albicans isolates and 14 C. dubliniensis isolates) were also investigated for intra-species variability. All tested isolates produced identical RFLP patterns to their respective reference strains except one initially misidentified isolate. Our method offers a simple...

Evaluation of PCR-Restriction Profile Analysis and IS2404 Restriction Fragment Length Polymorphism and Amplified Fragment Length Polymorphism Fingerprinting for Identification and Typing of Mycobacterium ulcerans and M. marinum

Chemlal, K.; Huys, G.; Fonteyne, P.-A.; Vincent, V.; Lopez, A. G.; Rigouts, L.; Swings, J.; Meyers, W. M.; Portaels, F.
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /09/2001 EN
Relevância na Pesquisa
86.27%
Mycobacterium ulcerans and M. marinum are emerging necrotizing mycobacterial pathogens that reside in common reservoirs of infection and exhibit striking pathophysiological similarities. Furthermore, the interspecific taxonomic relationship between the two species is not clear as a result of the very high phylogenetic relatedness (i.e., >99.8% 16S rRNA sequence similarity), in contrast to only 25 to 47% DNA relatedness. To help understand the genotypic affiliation between these two closely related species, we performed a comparative analysis including PCR restriction profile analysis (PRPA), IS2404 restriction fragment length polymorphism (RFLP), and amplified fragment length polymorphism (AFLP) on a set of M. ulcerans (n = 29) and M. marinum (n = 28) strains recovered from different geographic origins. PRPA was based on a triple restriction of the 3′ end region of 16S rRNA, which differentiated M. ulcerans into three types; however, the technique could not distinguish M. marinum from M. ulcerans isolates originating from South America and Southeast Asia. RFLP based on IS2404 produced six M. ulcerans types related to six geographic regions and did not produce any band with M. marinum, confirming the previous findings of Chemlal et al. (K. Chemlal...

Restriction fragment length polymorphism linkage map for Arabidopsis thaliana.

Chang, C; Bowman, J L; DeJohn, A W; Lander, E S; Meyerowitz, E M
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /09/1988 EN
Relevância na Pesquisa
86.27%
We have constructed a restriction fragment length polymorphism linkage map for the nuclear genome of the flowering plant Arabidopsis thaliana. The map, containing 90 randomly distributed molecular markers, is physically very dense; greater than 50% of the genome is within 1.9 centimorgans, or approximately 270 kilobase pairs, of the mapped DNA fragments. The map was based on the meiotic segregation of markers in two different crosses. The restriction fragment length polymorphism linkage groups were integrated with the five classically mapped linkage groups by virtue of mapped mutations included in these crosses. Markers consist of both cloned Arabidopsis genes and random low-copy-number genomic DNA clones that are able to detect polymorphisms with the restriction enzymes EcoRI, Bgl II, and/or Xba I. These cloned markers can serve as starting points for chromosome walking, allowing for the isolation of Arabidopsis genes of known map location. The restriction fragment length polymorphism map also can associate clones of unknown gene function with mutant phenotypes, and vice versa.

Use of Multiplex Terminal Restriction Fragment Length Polymorphism for Rapid and Simultaneous Analysis of Different Components of the Soil Microbial Community▿

Singh, Brajesh K.; Nazaries, Loic; Munro, Stacey; Anderson, Ian C.; Campbell, Colin D.
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
86.28%
A multiplex terminal restriction fragment length polymorphism (M-TRFLP) fingerprinting method was developed and validated for simultaneous analysis of the diversity and community structure of two or more microbial taxa (up to four taxa). The reproducibility and robustness of the method were examined using soil samples collected from different habitats. DNA was PCR amplified separately from soil samples using individual taxon-specific primers for bacteria, archaea, and fungi. The same samples were also subjected to a multiplex PCR with the primers for all three taxa. The terminal restriction fragment length polymorphism profiles generated for the two sets of PCR products were almost identical not only in terms of the presence of peaks but also in terms of the relative peak intensity. The M-TRFLP method was then used to investigate rhizosphere bacterial, fungal, and rhizobial/agrobacterial communities associated with the dwarf shrub Calluna vulgaris growing in either open moorland, a mature pine forest, or a transition zone between these two habitats containing naturally regenerating pine trees. Rhizosphere microbial communities associated with Vaccinium myrtillus collected from the native pine forest were also investigated. In this study...

MiCA: A web-based tool for the analysis of microbial communities based on terminal-restriction fragment length polymorphisms of 16S and 18S rRNA genes

Shyu, C.; Soule, T.; Bent, S.; Foster, J.; Forney, L.
Fonte: Springer-Verlag Publicador: Springer-Verlag
Tipo: Artigo de Revista Científica
Publicado em //2007 EN
Relevância na Pesquisa
96.12%
A web-based resource, Microbial Community Analysis (MiCA), has been developed to facilitate studies on microbial community ecology that use analyses of terminal-restriction fragment length polymorphisms (T-RFLP) of 16S and 18S rRNA genes. MiCA provides an intuitive web interface to access two specialized programs and a specially formatted database of 16S ribosomal RNA sequences. The first program performs virtual polymerase chain reaction (PCR) amplification of rRNA genes and restriction of the amplicons using primer sequences and restriction enzymes chosen by the user. This program, in silico PCR and Restriction (ISPaR), uses a binary encoding of DNA sequences to rapidly scan large numbers of sequences in databases searching for primer annealing and restriction sites while permitting the user to specify the number of mismatches in primer sequences. ISPaR supports multiple digests with up to three enzymes. The number of base pairs between the 5′ and 3′ primers and the proximal restriction sites can be reported, printed, or exported in various formats. The second program, APLAUS, infers a plausible community structure(s) based on T-RFLP data supplied by a user. APLAUS estimates the relative abundances of populations and reports a listing of phylotypes that are consistent with the empirical data. MiCA is accessible at http://mica.ibest.uidaho.edu/.; Conrad Shyu...

Identification of Borrelia burgdorferi ospC Genotypes in Host Tissue and Feeding Ticks by Terminal Restriction Fragment Length Polymorphisms

Tsao, K.; Bent, S.; Fish, D.
Fonte: Amer Soc Microbiology Publicador: Amer Soc Microbiology
Tipo: Artigo de Revista Científica
Publicado em //2013 EN
Relevância na Pesquisa
96.04%
We developed a high-throughput method based on terminal restriction fragment length polymorphisms (T-RFLP) to identify ospC genotypes from field-collected samples of Borrelia burgdorferi. We first validated the method by analyzing B. burgdorferi ospC previously identified by sequencing. We then analyzed and compared ospC genotypes detected from ear biopsy tissue from natural populations of the white-footed mouse, a major B. burgdorferi reservoir host species in the eastern United States, and larval ticks feeding on those individual mice. The T-RFLP method enabled us to distinguish all 17 ospC genotypes tested, as well as mixed samples containing more than one genotype. Analysis costs compare favorably to those of alternative ospC identification methods. The T-RFLP method will facilitate large-scale field studies to advance our understanding of genotype-specific transmission patterns.; Kimberly Tsao, Stephen J. Bent and Durland Fish

Statistical methods for characterizing diversity of microbial communities by analysis of terminal restriction fragment length polymorphisms of 16S rRNA genes

Abdo, Z.; Schutte, U.; Bent, S.; Williams, C.; Forney, L.; Joyce, P.
Fonte: Blackwell Science Ltd Publicador: Blackwell Science Ltd
Tipo: Artigo de Revista Científica
Publicado em //2006 EN
Relevância na Pesquisa
96.04%
The analysis of terminal restriction fragment length polymorphisms (T-RFLP) of 16S rRNA genes has proven to be a facile means to compare microbial communities and presumptively identify abundant members. The method provides data that can be used to compare different communities based on similarity or distance measures. Once communities have been clustered into groups, clone libraries can be prepared from sample(s) that are representative of each group in order to determine the phylogeny of the numerically abundant populations in a community. In this paper methods are introduced for the statistical analysis of T-RFLP data that include objective methods for (i) determining a baseline so that 'true' peaks in electropherograms can be identified; (ii) a means to compare electropherograms and bin fragments of similar size; (iii) clustering algorithms that can be used to identify communities that are similar to one another; and (iv) a means to select samples that are representative of a cluster that can be used to construct 16S rRNA gene clone libraries. The methods for data analysis were tested using simulated data with assumptions and parameters that corresponded to actual data. The simulation results demonstrated the usefulness of these methods in their ability to recover the true microbial community structure generated under the assumptions made. Software for implementing these methods is available at http://www.ibest.uidaho.edu/tools/trflp_stats/index.php.; Zaid Abdo...

TIPIFICAÇÃO DAS ESPECIFICIDADES HLA-DR E HLA-DQ: ESTUDO COMPARATIVO UTILIZANDO SOROLOGIA, E AVALIAÇÃO DO POLIMORFISMO DO DNA GENÔMICO POR INTERMÉDIO DO TAMANHO DOS FRAGMENTOS GERADOS POR CLIVAGEM COM ENZIMAS DE RESTRIÇÃO; HLA-DR AND HLA-DQ TYPING: A COMPARATIVE STUDY USING SEROLOGY AND RESTRICTION FRAGMENT LENGTH POLYMORPHISM (RFLP) ANALYSIS

Donadi, Eduardo A.; Santos, Cássia M. Paula; Nepom, Gerald T.
Fonte: Universidade de São Paulo. Faculdade de Medicina de Ribeirão Preto Publicador: Universidade de São Paulo. Faculdade de Medicina de Ribeirão Preto
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; Formato: application/pdf
Publicado em 30/03/2000 ENG
Relevância na Pesquisa
116.16%
Embora as tipificações sorológicas dependam da expressão adequada de moléculas HLA de classe II, nas superfícies celulares, da viabilidade celular e da presença de um painel adequado de anti-soros, esse método tem sido utilizado há muitos anos e as tipificações por biologia molecular têm suplantado os problemas. A avaliação do polimorfismo dos genes HLA por intermédio da variação do tamanho dos fragmentos gerados pós digestão com enzimas de restrição (RFLP) foi o primeiro método molecular a ser utilizado para esse fim. A sorologia e o método utilizando RFLP definem os alelos HLA sem muita resolutividade, no entanto, o método utilizando RFLP tem sido considerado melhor do que a sorologia. Assim, neste estudo, fizemos análise das tipificações dos antígenos/alelos HLA de classe II (HLA-DR e HL-DQ), comparando os dois métodos.; Serology has been used for HLA typing for many decades; however, serological typing of histocompatibility class II molecules depends on the adequate expression of these molecules on the surface of B lymphocytes, the availability of viable cells and a complete set of antisera. HLA typing at the genomic level has supplanted these pitfalls. The utilization of restriction fragment length polymorphism (RFLP) was the first approach to the HLA typing at molecular level. Although serology and RFLP methods define HLA specificities at low resolution level...

Discovery of a functional polymorphism in human glutathione transferase Zeta by expressed sequence Tag database analysis

Blackburn, Anneke; Tzeng, Huey-Fen; Anders, Michael; Board, Philip
Fonte: Lippincott Williams & Wilkins Publicador: Lippincott Williams & Wilkins
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
96.08%
Analysis of the expressed sequence tag (EST) database by sequence alignment allows a rapid screen for polymorphisms in proteins of physiological interest. The human zeta class glutathione transferase GSTZ1 has recently been characterized and analysis of expressed sequence tag clones suggested that this gene may be polymorphic. This report identifies three GSTZ1 alleles resulting from A to G transitions at nucleotides 94 and 124 of the coding region, GSTZ1*A - A94A124; GSTZ1*B - A94G124; GSTZ1*C - G94G124. Polymerase chain reaction/restriction fragment length polymorphism analysis of a control Caucasian population (n = 141) showed that all three alleles were present, with frequencies of 0.09, 0.28 and 0.63 for Z1*A, Z1*B and Z1*C, respectively. These nucleotide substitutions are non-synonymous, with A to G at positions 94 and 124 encoding Lys32 to Glu and Arg42 to Gly substitutions, respectively. The variant proteins were expressed in Escherichia coli as 6X His-tagged proteins and purified by Ni-agarose column chromatography. Examination of the activities of recombinant proteins revealed that GSTZ1a-1a displayed differences in activity towards several substrates compared with GSTZ1b-1b and GSTZ1c-1c, including 3.6-fold higher activity towards dichloroacetate. This report demonstrates the discovery of a functional polymorphism by analysis of the EST database. (C) 2000 Lippincott Williams and Wilkins.