Características espectrais da soja ao longo do ciclo vegetativo com imagens landsat 5/TM em área agrícola no oeste do Paraná

The objective of this study was to analyze changes in the spectral behavior of the soybean crop through spectral profiles of the vegetation indexes NDVI and GVI, expressed by different physical values such as apparent bi-directional reflectance factor (BRF), surface BRF, and normalized BRF derived from images of the Landsat 5/TM. A soybean area located in Cascavel, Paraná, was monitored by using five images of Landsat 5/TM during the 2004/2005 harvesting season. The images were submitted to radiometric transformation, atmospheric correction and normalization, determining physical values of apparent BRF, surface BRF and normalized BRF. NDVI and GVI images were generated in order to distinguish the soybean biomass spectral response. The treatments showed different results for apparent, surface and normalized BRF. Through the profiles of average NDVI and GVI, it was possible to monitor the entire soybean cycle, characterizing its development. It was also observed that the data from normalized BRF negatively affected the spectral curve of soybean crop, mainly, during the phase of vegetative growth, in the 12-9-2004 image.

Modelos de regressão lineares para estimativa de produtividade da soja no oeste do Paraná, utilizando dados espectrais

The main objective of this work was to evaluate the linear regression between spectral response and soybean yield in regional scale. In this study were monitored 36 municipalities from the west region of the states of Parana using five images of Landsat 5/TM during 2004/05 season. The spectral response was converted in physical values, apparent and surface reflectances, by radiometric transformation and atmospheric corrections and both used to calculate NDVI and GVI vegetation indices. Those ones were compared by multiple and simple regression with government official yield values (IBGE). Diagnostic processing method to identify influents values or collinearity was applied to the data too. The results showed that the mean surface reflectance value from all images was more correlated with yield than individual dates. Further, the multiple regressions using all dates and both vegetation indices gave better results than simple regression.

46,XX Male - Testicular Disorder of Sexual Differentiation (DSD): hormonal, molecular and cytogenetic studies

The XX male syndrome - Testicular Disorder of Sexual Differentiation (DSD) is a rare condition characterized by a spectrum of clinical presentations, ranging from ambiguous to normal male genitalia. We report hormonal, molecular and cytogenetic evaluations of a boy presenting with this syndrome. Examination of the genitalia at age of 16 months, showed: penis of 3.5 cm, proximal hypospadia and scrotal testes. Pelvic ultrasound did not demonstrate Mullerian duct structures. Karyotype was 46,XX. Gonadotrophin stimulation test yielded insufficient testosterone production. Gonadal biopsy showed seminiferous tubules without evidence of Leydig cells. Molecular studies revealed that SRY and TSPY genes and also DYZ3 sequences were absent. In addition, the lack of deletions or duplications of SOX9, NR5A1, WNT4 and NROB1 regions was verified. The infant was heterozygous for all microsatellites at the 9p region, including DMRT1 gene, investigated. Only 10% of the patients are SRY-negative and usually they have ambiguous genitalia, as the aforementioned patient. The incomplete masculinization suggests gain of function mutation in one or more genes downstream to SRY gene.

Six new cases confirm the clinical molecular profile of complete combined 17α-hydroxylase/ 17,20-lyase deficiency in Brazil

In 2004, Costa-Santos and cols. reported 24 patients from 19 Brazilian families with 17α-hydroxylase deficiency and showed that p.W406R and p.R362C corresponded to 50% and 32% of CYP17A1 mutant alleles, respectively. The present report describes clinical and molecular data of six patients from three inbred Brazilian families with 17α-hydroxlyse deficiency. All patients had hypogonadism, amenorrhea and hypertension at diagnosis. Two sisters were found to be 46,XY with both gonads palpable in the inguinal region. All patients presented hypergonadotrophic hypogonadism, with high levels of ACTH (> 104 ng/mL), suppressed plasmatic renin activity, low levels of potassium (< 2.8 mEq/L) and elevated progesterone levels (> 4.4 ng/mL). Three of them, including two sisters, were homozygous for p.W406R mutation and the other three (two sisters and one cousin) were homozygous for p.R362C. The finding of p.W406R and p.R362C in the CYP17A1 gene here reported in additional families, confirms them as the most frequent mutations causing complete combined 17α-hydroxylase/17,20-lyase deficiency in Brazilian patients.

Phenotypic variability in a family with x-linked adrenoleukodystrophy caused by the p.Trp132Ter mutation

X-linked adrenoleukodystrophy (X-ALD) is an inherited disease with clinical heterogeneity varying from presymptomatic individuals to rapidly progressive cerebral ALD forms. This disease is characterized by increased concentration of very long chain fatty acids (VLCFAs) in plasma and in adrenal, testicular and nervous tissues. Affected individuals can be classified in different clinical settings, according to phenotypic expression and age at onset of initial symptoms. Molecular defects in X-ALD individuals usually result from ABCD1 gene mutations. In the present report we describe clinical data and the ABCD1 gene study in two boys affected with the childhood cerebral form that presented with different symptomatic manifestations at diagnosis. In addition, their maternal grandfather had been diagnosed with Addison's disease indicating phenotypic variation for X-ALD within this family. The mutation p.Trp132Ter was identified in both male patients; additionally, three females, out of eleven family members, were found to be heterozygous after screening for this mutation. In the present report, the molecular analysis was especially important since one of the heterozygous females was in first stages of pregnancy. Therefore, depending on the fetus outcome, if male and p.Trp132Ter carrier, storage of the umbilical cord blood should be recommended as hematopoietic stem cell transplantation could be considered as an option for treatment in the future.

Medida da capacidade antioxidante de fluidos biologicos por voltametria de pulso diferencial associada ao uso de surfactante como resposta as adaptações geradas pelo exercicio

Universidade Estadual de Campinas . Faculdade de Educação Física

Manipulação do genoma humano: ética e direito

A biologia molecular tem fornecido as ferramentas básicas para os geneticistas se aprofundarem nos mecanismos moleculares que influem na variação das doenças. Deve-se destacar a responsabilidade científica e moral dos pesquisadores, uma vez que os cientistas devem imaginar as consequências morais da aplicação comercial de testes genéticos, já que esse fato envolve não só o indivíduo e suas famílias, mas toda a população. Além de ser preciso, também, fazer uma reflexão sobre como essas informações do genoma humano serão utilizadas, para o bem ou mal. O objetivo desta revisão foi trazer à luz do conhecimento dados sobre características éticas da aplicação da biologia molecular, relacionando-a com os direitos do ser humano. Após análise bibliográfica, pôde-se observar que o Projeto Genoma Humano gerou várias possibilidades, como identificação de genes associados a doenças com propriedades sinergísticas, mas modificando às vezes comportamentos ao intervir geneticamente no ser humano, trazendo benefícios ou malefícios sociais. O grande desafio é decidir o que a humanidade pretende em relação a este gigantesco salto.

Imunofenótipo e evolução de câncer de mama: comparação entre mulheres muito jovens e mulheres na pós-menopausa

OBJETIVO: avaliar características clínicas, patológicas e moleculares de carcinomas mamários em mulheres muito jovens em comparação a tumores de mulheres na pós-menopausa. MÉTODOS: foram selecionados 106 casos de câncer de mama de mulheres jovens e 130 casos de mulheres pós-menopausa. Foram analisados dados clínicos (idade ao diagnóstico, estadiamento, ocorrência de metástases, tempo de sobrevida global e livre de doença), anátomo-patológicos (tamanho do tumor, tipo e grau histológico do tumor primário) e marcadores moleculares (receptores de estrógeno e progesterona, HER2, p53, p63, citoqueratinas 5 e 14 e EGFR) com uso da imunoistoquímica empregando microarranjo de tecido. Foi analisada a relação entre as características clínico-patológicas, imunoistoquímicas e de sobrevidas global e livre de doença. RESULTADOS: as pacientes muito jovens apresentaram maior frequência de nuliparidade (p=0,03), maior diâmetro dos tumores (p<0,000), estadiamento clínico mais avançado (p=0,01), maior número de linfonodos positivos (p=0,001) e tumores pouco diferenciados (p=0,004). A maioria das pacientes jovens recebeu tratamento com quimioterapia (90,8%) e radioterapia (85,2%) e em menor proporção com tamoxifeno (31,5%), comparado às mulheres na pós-menopausa. Observamos baixa positividade para o receptor de estrógeno (49,1%; p=0,01) e alta positividade para a proteína HER2 (28,7%; p=0,03) nas mulheres jovens. O fenótipo triplo-negativo foi observado em 29,6% no grupo jovem e em 20% nas mulheres na pós-menopausa. Os tumores de fenótipo basal foram mais frequentes nas mulheres jovens (50%). As metástases sistêmicas ocorreram em 55,3% dos casos nas jovens e em 39,2% nas idosas. As sobrevidas global e livre de doença em cinco anos foram, respectivamente, 63 e 39% para as mulheres jovens e 75 e 67% para o grupo de mulheres na pós-menopausa. CONCLUSÕES: carcinomas mamários de mulheres muito jovens têm características clínicas, patológicas e moleculares mais agressivas quando comparadas às mulheres acima de 50 anos.

Albedo à superfície a partir de imagens Landsat 5 em áreas de cana-de-açúcar e cerrado

Propôs-se, neste trabalho, estimar dados de albedo à superfície terrestre usando-se o sensor Thematic Mapper (TM) do satélite LANDSAT 5 e compará-lo com dados de duas estações agrometeorológicas localizadas em região de Cerrado e a outra em cultivo da cana-de-açúcar. A região de estudo está localizada no município de Santa Rita do Passa Quatro, SP, Brasil. Para a realização do estudo obtiveram-se seis imagens orbitais do satélite Landsat 5 sensores TM, na órbita 220 e ponto 75, nas datas de 22/02, 11/04, 29/05, 01/08, 17/08 e 21/11, todas do ano de 2005, a que correspondem os dias juliano de 53, 101, 149, 213, 229 e 325, respectivamente. As correções geométricas para as imagens foram realizadas e geradas as cartas de albedo. O algoritmo SEBAL estimou satisfatoriamente os valores de albedo de superfícies sobre áreas de cerrado e de cana-de-açúcar, na região de Santa Rita do Passa Quatro, SP, consistentes com observações realizadas do albedo à superfície.

Molecular systematics of Thorea (Rhodophyta, Thoreales) species in Brazil

This study aimed to evaluate species level taxonomy and phylogenetic relationship among Thorea species in Brazil and other regions of the world using two molecular markers - RUBISCO large subunit plastid gene (rbcL) and nuclear small-subunit ribosomal DNA (SSU rDNA). Three samples of Thorea from Brazil (states of Mato Grosso do Sul and São Paulo) and one sample from Dominican Republic (DR) were sequenced. Analyses based on partial sequences of rbcL (1,282 bp) and complete sequences of SSU (1,752 bp) were essentially congruent and revealed that Thoreales formed a distinct monophyletic clade, which had two major branches with high support, representing the genera Thorea and Nemalionopsis. Thorea clade had four main branches with high support for all analyses, each one representing the species: 1) T. gaudichaudii C. Agardh from Asia (Japan and Philippines) - this clade occurred only in the rbcL analyses; 2) T. violacea Bory from Asia (Japan) and North America (U.S.A. and DR); 3) T. hispida (Thore) Desvaux from Europe (England) and Asia (Japan); 4) a distinct group with the three Brazilian samples (sequence identity: rbcL 97.2%, 1,246 bp; SSU 96.0-98.1%, 1,699-1,720 bp). The Brazilian samples clearly formed a monophyletic clade based on both molecular markers and was interpreted as a separate species, for which we resurrected the name T. bachmannii Pujals. Morphological and molecular evidences indicate that the Thoreales is well-resolved at ordinal and generic levels. In contrast, Thorea species recognized by molecular data require additional characters (e.g. reproductive and chromosome numbers) to allow consistent and reliable taxonomic circumscription aiming at a world revision based on molecular and morphological evidences.

Revisão taxonômica de Croton sect. Lamprocroton (Müll. Arg.) Pax (Euphorbiaceae s.s.)

Croton is the second bigger and more diverse genus in the family Euphorbiaceae, with about 1,200 species distributed in 40 sections, occurring in all tropical areas, most of them in Americas. In South America, Brazil is the country in which a larger number of taxa are found, ca. 356. According to recent classification, the genus belongs to the tribe Crotoneae, and despite the wide and morphological diversity, it would be a monophyletic taxon. However, a phylogenetic analysis using markers of ITS region from nuclear ribosomal DNA, and of trnL-F from plastidial DNA, showed that Croton, like traditionally circumscribed, is not a monophyletic taxon. A taxonomic revision of Croton section Lamprocroton (Müll. Arg.) Pax is presented here. It is a Neotropical group with most of its species occurring from Southeast and South Brazil to southern South America (Uruguay and Argentina). Morphologically, the members of Lamprocroton are characterized as monoecious or dioecious shrubs or subshrubs, with a lepidote indumentum at least in part of foliage, entire leaves with no glands. The staminate flowers have 9 to 16 stamens and the pistillate flowers may have equal or unequal sepals, reduced to absent petals, and styles once or twice bifid. Overall, are recognized 26 species in the group, three of them new to the science. Identification key, morphological descriptions, illustrations, phenological period, as well as data on geographic distribution and general comments of each species are presented. Four taxa were excluded from C. sect. Lamprocroton because they do not show the morphological features that are diagnostics of the section. Four species that are poorly known were not included in the taxonomic treatment.

Medidas de audição de pais de indivíduos com deficiência auditiva de herança autossômica recessiva

TEMA: avaliação audiológica de pais de indivíduos com perda auditiva de herança autossômica recessiva. OBJETIVO: estudar o perfil audiológico de pais de indivíduos com perda auditiva, de herança autossômica recessiva, inferida pela história familial ou por testes moleculares que detectaram mutação no gene GJB2, responsável por codificar a Conexina 26. MÉTODO: 36 indivíduos entre 30 e 60 anos foram avaliados e divididos em dois grupos: grupo controle, sem queixas auditivas e sem história familiar de deficiência auditiva, e grupo de estudos composto por pais heterozigotos em relação a genes de surdez de herança autossômica recessiva inespecífica ou portadores heterozigotos de mutação no gene da Conexina 26. Todos foram submetidos à audiometria tonal liminar (0,25kHz a 8), audiometria de altas freqüências (9kHz a 20) e emissões otoacústicas produtos de distorção (EOAPD). RESULTADOS: houve diferenças significativas na amplitude das EOAPD nas freqüências 1001 e 1501Hz entre os grupos, sendo maior a amplitude no grupo controle. Não houve diferença significativa entre os grupos para os limiares tonais de 0,25 a 20KHz. CONCLUSÃO: as EOAPD foram mais eficazes, em comparação com a audiometria tonal liminar, para detectar diferenças auditivas entre os grupos. Mais pesquisas são necessárias para verificar a confiabilidade destes dados.

Sex ratio and morphological characteristics of rufous gnateaters, Conopophaga lineata (Aves, Passeriformes) in Atlantic forest fragments

Unequal sex ratios lead to the loss of genetic variability, decreasing the viability of populations in the long term. Anthropogenic activities often disturb the natural habitats and can cause alterations in sex ratio and morphological characteristics of several species. Forest fragmentation is a major conservation concern, so that understanding its effects in natural populations is essential. In this study, we evaluated the sex ratio and the morphological characteristics of Rufous Gnateaters (Conopophaga lineata (Wied, 1831)) in small and large forest fragments in Minas Gerais, Brazil. Birds (n = 89) were sexed by plumage characteristics and molecular markers. The molecular analysis showed that plumage is not a totally reliable method for sexing Rufous Gnateaters. We observed that sex ratio did not differ between large and small forest fragments, but birds in small fragments had larger wings and tarsus. Wing and tarsus changes may affect the movement ability of individuals within and among forest fragments. In conclusion, Rufous Gnateaters have been able to survive in both small and large Atlantic rain forest fragments without altering their sex ratio, but morphological changes can be prejudicial to their long term survival.

Controle da adipogênese por ácidos graxos

A obesidade é um dos principais problemas de saúde pública. Indivíduos obesos são mais suscetíveis a desenvolver doenças cardiovasculares e diabetes melito tipo 2. A obesidade resulta do aumento no tamanho e no número de adipócitos. O balanço entre adipogênese e adiposidade determina o grau de obesidade do indivíduo. Adipócitos maduros secretam adipocinas, tais como TNFα, IL-6, leptina e adiponectina, e lipocina, o ácido palmitoleico ω-7. A produção de adipocinas é maior na obesidade, o que contribui para o estabelecimento de resistência periférica à insulina. O conhecimento dos eventos moleculares que regulam a diferenciação dos pré-adipócitos e de células-tronco mesenquimais em adipócitos (adipogênese) é importante para o entendimento da gênese da obesidade. A ativação do fator de transcrição PPARγ é essencial na adipogênese. Certos ácidos graxos são ligantes de PPARγ e podem, assim, controlar a adipogênese. Além disso, alguns ácidos graxos atuam como moléculas sinalizadoras em adipócitos, regulando sua diferenciação ou morte. Dessa forma, a composição lipídica da dieta e os agonistas de PPARγ podem regular o balanço entre adipogênese e morte de adipócitos e, portanto, a obesidade.

Enzyme kinetics, structural analysis and molecular modeling studies on a series of Schistosoma mansoni PNP inhibitors

The enzyme purine nucleoside phosphorylase from Schistosoma mansoni (SmPNP) is an attractive molecular target for the development of novel drugs against schistosomiasis, a neglected tropical disease that affects about 200 million people worldwide. In the present work, enzyme kinetic studies were carried out in order to determine the potency and mechanism of inhibition of a series of SmPNP inhibitors. In addition to the biochemical investigations, crystallographic and molecular modeling studies revealed important molecular features for binding affinity towards the target enzyme, leading to the development of structure-activity relationships (SAR).