天山不同海拔高度下长鳞红景天种群遗传多样性分析

长鳞红景天（Rhodiola gelida）属景天科红景天属，多年生草本。主要分布在我国新疆中部天山。在天山一号冰川观测试验站附近的高寒草甸上，从海拔3850m~4010m均有长鳞红景天分布。长鳞红景天是一种重要的药用植物，但目前尚未见到有关其遗传多样性方面的研究报道。本文利用相关序列扩增多态性（sequence-related amplified polymorphism，SRAP）分子标记技术，对新疆天山不同海拔高度3个长鳞红景天种群的遗传多样性，种群内及种群间的遗传变异进行研究，为有效保护和合理利用长鳞红景天物种资源提供理论依据。主要结果如下： （1）基于CTAB法，建立了适合长鳞红景天的DNA提取方法，获得的DNA经琼脂糖电泳和紫外分析仪检测，浓度和质量均较高。该法有利于去除长鳞红景天植物材料中多糖、多酚类等物质，获得的高质量基因组DNA能够满足后续的PCR实验要求。 （2）采用正交实验对影响长鳞红景天SRAP-PCR反应的4个主要因素（Taq酶用量、Mg2+浓度、dNTP浓度、引物浓度）进行优化试验，选出这4个因素的最佳水平组合，建立了长鳞红景天SRAP-PCR最佳反应体系。同时，根据最佳体系筛选出扩增稳定、多态性丰富的SRAP引物。通过梯度PCR确定引物的最佳退火温度，得到了适合长鳞红景天SRAP-PCR反应的最佳扩增程序。 （3）对20对SRAP引物的扩增结果进行统计分析显示：长鳞红景天物种水平的多态位点百分率(P)为96.00 %，Shannon信息指数(I)为0.4484、基因多样性指数(H)为0.2922，表现出较高的遗传多样性水平；在海拔梯度上，长鳞红景天各种群间的遗传多样性水平有一定差异，但没有呈现规律性的变化；AMOVA分子变异分析显示，在总遗传变异中24.76 % 的变异存在于种群间，75.24 % 的变异存在于种群内，种群间的基因分化系数(Gst)为0.1749，表明3个长鳞红景天种群的变异主要存在于种群内，但种群间也出现了一定程度的遗传分化；长鳞红景天3个种群间的基因流为2.3595，遗传距离平均值为0.0981（变化范围：0.0768 ～0.1196），遗传距离较近，说明海拔高度对长鳞红景天的地理隔离较小；相关性分析表明长鳞红景天种群的遗传多样性与各生态因子的相关性均不显著。

Temporal and geographical distribution of measles virus genotypes

The nucleotide sequence encoding the C terminus of the nucleocapsid protein of measles virus (MV) is the most variable in the genome. The sequence of this region is reported for 21 new MV strains and for virus RNA obtained from cases of subacute panencephalitis (SSPE) tissue. The nucleotide sequence of a total of 65 MV strains has been analysed using the CLUSTAL program to determine the relationships between the strains. An unrooted tree shows that eight different genotypes can be discerned amongst the sequences analysed so far. The data show that the C-terminal coding sequence of the nucleocapsid gene, although highly variable between strains, is stable in a given strain and does not appear to diverge in tissue culture. It therefore provides a good 'signature' sequence for specific genotypes. The sequence of this region can be used to discriminate new imported viruses from old 'endemic' strains of MV in a geographical area. The different genotypes are not geographically restricted although some appear to be the mainly 'endemic' types in large areas of the world. In global terms there appears to be at least four co-circulating genotypes of MV. The low level of divergence in the Edmonston lineage group isolated before 1970 indicates that some isolates are probably laboratory contaminants. This applies to some SSPE isolates such as the Halle, Mantooth and Horta-Barbosa strains as well as some wild-type isolates from that period.

Further evidence consistent with Yqh as an indicator of risk of gonadal blastoma in Y-bearing mosaic Turner syndrome

An 8-year-old girl with some features of Turner syndrome and karyotype 45X/46XY had developed a bilateral gonadoblastoma in her rudimentary ovaries. Her normal Y chromosome showed the characteristic distal fluorescence, as seen in her father's. Another mosaic, this time 45X/46XidicY, and also with some Turner features had rudimentary ovaries, but no gonadoblastoma had developed at age 14. The nature of her idicY, which showed no fluorescent distal Yq and had one of the centromeres inactivated, was confirmed by in situ hybridisation with a Yp-specific probe. Using primers from a human Yp-specific sequence, we amplified DNA extracted from paraffin-embedded ovarian tissue from both cases, and from a normal testicle and a normal ovary as controls. The finding of the expected Y-derived PCR product in the rudimentary gonads from these mosaic patients indicates the presence of their Y chromosome in both. We discuss the validity of the findings, and the possible role of sequences in or near the fluorescent part of Yq in the origin of gonadoblastoma in Y-bearing mosaic Turner syndrome.

Locating and sequencing of the E3 and neighbouring regions in bovine advenovirus type 2

Adenoviruses are nonenveloped icosahedral shaped particles. The double stranded DNA viral genome is divided into 5 major early transcription units, designated E1 A, E1 B, and E2 to E4, which are expressed in a regulated manner soon after infection. The gene products of the early region 3 (E3), shown to be nonessential for viral replication in vitro, are believed to be involved in counteracting host immunosurveillance. In order to sequence the E3 region of Bovine adenovirus type 2 (BAV2) it was necessary to determine the restriction map for the plasmid pEA48. A physical restriction endonuclease map for BamHl, Clal, Eco RI, Hindlll, Kpnl, Pstt, Sail, and Xbal was constructed. The DNA insert in pEA48 was determined to be viral in origin using Southern hybridization. A human adenovirus type 5 recombinant plasmid, containing partial DNA fragments of the two transcription units L4 and L5 that lie just outside the E3, was used to localize this region. The recombinant plasmid pEA was subcloned to facilitate sequencing. The DNA sequences between 74.8 and 90.5 map units containing the E3, the hexon associated protein (pVIII), and the fibre gene were determined. Homology comparison revealed that the genes for the hexon associated pV11I and the fibre protein are conserved. The last 70 amino acids of the BAV2 pV11I were the most conserved, showing a similarity of 87 percent with Ad2 pV1I1. A comparison between the predicted amino acid sequences of BAV2 and Ad40, Ad41 , Ad2 and AdS, revealed that they have an identical secondary structure consisting of a tail, a shaft and a knob. The shaft is composed of 22, 15 amino acid motifs, with periodic glycines and hydrophobic residues. The E3 region was found to consist of about 2.3 Kbp and to encode four proteins that were greater than 60 amino acids. However, these four open reading frames did not show significant homology to any other known adenovirus DNA or protein sequence.

Integration of retrotransposons-based markers in a linkage map of barley

A deeper understanding of random markers is important if they are to be employed for a range of objectives. The sequence specific amplified polymorphism (S-SAP) technique is a powerful genetic analysis tool which exploits the high copy number of retrotransposon long terminal repeats (LTRs) in the plant genome. The distribution and inheritance of S-SAP bands in the barley genome was studied using the Steptoe × Morex (S × M) double haploid (DH) population. Six S-SAP primer combinations generated 98 polymorphic bands, and map positions were assigned to all but one band. Eight putative co-dominant loci were detected, representing 16 of the mapped markers. Thus at least 81 of the mapped S-SAP loci were dominant. The markers were distributed along all of the seven chromosomes and a tendency to cluster was observed. The distribution of S-SAP markers over the barley genome concurred with the knowledge of the high copy number of retrotransposons in plants. This experiment has demonstrated the potential for the S-SAP technique to be applied in a range of analyses such as genetic fingerprinting, marker assisted breeding, biodiversity assessment and phylogenetic analyses.

Clinical correlations of human cytomegalovirus strains and viral load in kidney transplant recipients

Little is known about clinical differences associated with cytomegalovirus (CMV) infection by distinct strains in renal transplant patients. Different clinical pictures may be associated with specific viral genotypes. viral load, as well as host factors. The objective of this study was to identify CMV strains to determine viral load (antigenemia), and their correlation with clinical data in renal transplant recipients. Seventy-one patients were enrolled, comprising 91 samples. After selection, polymorphonuclear cells were used to amplify and sequence the gB region of CMV DNA. The sequences were analyzed to ascertain the frequency of different genotypes. Additionally, the results of this Study showed that the gB coding gene presents a great variability, revealing a variety of patterns: classical gB (1.4%), gB1V (46.4%), classical gB2 (35.2%), gB2V (2.8%), gB3 (1.4%), classical gB4 (4.9%) and gB4V (4.9%). The mean viral load in kidney transplant patient was 75.1 positive cells (1-1000). A higher viral load was observed in patients with genotype 4 infection. Statistically significant differences were detected between gB1 and gB4 (p=0.010), and between gB2 and gB4 (p=0.021). The average numbers of positive cells in relation to clinical presentation were: 34.5 in asymptomatic, 49.5 in CMV associated syndrome and 120.7 in patients with invasive disease (p=0.048). As a group, gB1 was the most frequent strain and revealed a potential risk for developing invasive disease. Viral load also seemed to be important as a marker associated with clinical presentation of the disease. (C) 2008 Elsevier B.V. All rights reserved.

Plant or fungal sequences? An alternative optimized PCR protocol to avoid ITS (nrDNA) misamplification

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Evaluation of an ELISA for detection of antibodies to Babesia bigemina in cattle and it's application in an epidemiological survey in Brazil

Um ensaio de imunoadsorção enzimática (ELISA) baseado em antígeno bruto foi avaliado na detecção de anticorpos contra Babesia bigemina. A sensibilidade e a especificidade do teste foram de 98,0% e 99,0%, respectivamente. Concordando com a alta especificidade do teste, não foram verificadas reações cruzadas com soros de bezerros inoculados três vezes com 10(7) merozoítos de Babesia bovis. Com relação à comparação do ELISA com a imunofluorescência indireta (IFAT) na detecção de anticorpos contra B. bigemina em bezerros experimentalmente infectados com cinco isolados brasileiros geograficamente distintos deste hemoparasito, o IFAT foi capaz de detectar anticorpos um dia antes do ELISA na maioria dos soros dos animais. Houve uma boa concordância entre os resultados encontrados no ELISA e no IFAT com soros de bovinos de região de estabilidade enzoótica (k=0.61). No entanto, não houve concordância entre os testes sorológicos com soros de animais de área de instabilidade enzoótica (k=0.33). O ELISA foi empregado em um inquérito epidemiológico com 1.367 soros de quatro municípios do Pantanal de Mato Grosso do Sul e caracterizou esta região como uma área de estabilidade enzoótica, uma vez que as prevalências variaram de 87,7 a 98,9%. Dessa forma, este ELISA, que apresentou alta sensibilidade, especificidade e desempenho similar ao IFAT, pode ser utilizado no diagnóstico sorológico de B. bigemina.

Structural biology of membrane-acting peptides: Conformational plasticity of anticoccidial peptide PW2 probed by solution NMR

The bottleneck for the complete understanding of the structure-function relationship of flexible membrane-acting peptides is its dynamics. At the same time, not only the structure but also the dynamics are the key points for their mechanism of action. Our model is PW2, a TRP-rich, cationic peptide selected from phage display libraries that shows anticoccidial activity against Eimeria acervulina. In this manuscript we used a combination of several NMR techniques to tackle these difficulties. The structural features of the membrane-acting peptide PW2 was studied in several membrane mimetic environments: we compared the structural features of PW2 in SDS and DPC micelles, that were reported earlier, with the structure properties in different lipid vesicles and the peptide free in water. We were able to unify the structural information obtained in each of these systems. The structural constraints of the peptide free in water were fundamental for the understanding of plasticity necessary for the membrane interaction. Our data suggested that the WWR sequence is the region responsible for anchoring the peptide to the interfaces, and that this same region displays some degree of conformational order in solution. For PW2, we found that affinity is related to the aromatic region, by anchoring the peptide to the membrane, and specificity is related to the N- and C-termini, which are able to accommodate in the membrane due to its plasticity. (C) 2007 Elsevier B.V. All rights reserved.

Structural change and productivity growth, 20 years later: old problems, new opportunities

Includes bibliography

Overcoming the empty box syndrome": eterminants of income distribution in Latin America"

Includes bibliography

Structural change and productivity growth 20 years later: old problems, new opportunities. Summary

Includes bibliography

Caracterização morfométrica, patogênica e genética de isolados de Colletrotrichum gloeosporioides, agente causal da antracnose em manga (Mangifera indica L.)

Pós-graduação em Agronomia (Produção Vegetal) - FCAV

Caracterização molecular de acessos de capim-colchão (Digitaria nuda) e resposta à ametrina

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Amazônia, projeto desenvolvimentista, dissimulação e barbárie

O texto aborda o Projeto Desenvolvimentista da Ditadura Militar de 1964 na Amazônia, especificamente no período da Nova República (1986-1989), estabelecendo relação entre o seu fundamento dissimulador e a barbárie que marcou a vida da região a partir da implantação dos Grandes Projetos, especificamente da Hidrelétrica de Tucuruí, e seu reflexo no período em discussão.