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1.
J Hum Genet ; 55(2): 71-6, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19942933

RESUMO

The goal of the present study was to provide a complete and updated spectrum of cystic fibrosis (CF) transmembrane conductance regulator (CFTR) gene mutations in the Brazilian population combining all available in silico data for patients with CF in Brazil, including founder background and migration flow that consisted of the actual genetic pool of the Brazilian population. Information sources in international databases (PUBMED and SCIELO) were searched. The Brazilian population shows a wide variation in the frequency of CFTR mutations in states Rio Grande do Sul (RS), Santa Catarina (SC), Paraná (PR), São Paulo (SP), Rio de Janeiro (RJ), Minas Gerais (MG), Pará (PA) and Bahia (BA); this variation includes the most common mutation p.F508del. Apparently, this frequency variation is because of the different ethnic compositions. States such as SC and PR have a greater European admixture with almost 90% of CF alleles identified. In other states, such as BA, higher frequency of alleles that are common among African populations is seen. Overall, the CFTR mutational spectrum indicates the presence of European, African and Amerindian ethnic groups in the contemporary Brazilian CF patients. Here, we present an analysis of the CFTR allelic heterogeneity and discuss the origin of its genetic composition, in an attempt to provide improved perspective for the CF population screening in Brazil and genetic counseling.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/genética , Fibrose Cística/epidemiologia , Fibrose Cística/genética , Heterogeneidade Genética , Mutação/genética , População Negra/genética , Brasil/epidemiologia , Biologia Computacional , Fibrose Cística/etnologia , Emigração e Imigração , Testes Genéticos/estatística & dados numéricos , Humanos , Indígenas Sul-Americanos/genética , População Branca/genética
2.
Dalton Trans ; (34): 6816-24, 2009 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-19690694

RESUMO

The novel chain compound [Cu(Phtfac)(2)(NITpPy)](n) (where NITpPy = 4-pyridyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide and Phtfac = 4,4,4-trifluoro-1-phenylbutane-1,3-dione) was synthesized and characterized structurally, magnetically and by EPR. The compound contains two non equivalent Cu(II) ions, Cu1 and Cu2, located at inversion centers and bridged by a NITpPy ligand coordinating Cu1 through the pyridine donor atom, and Cu2 through a N-O group, resulting in a head-to-head chain structure. The chain exhibits an unusual spin topology with two alternating pairs of magnetic coupling constants. The magnetic behavior was modeled considering a 16-membered ring with alternating exchange couplings. The best fit parameters indicate a ferromagnetic (J(1) = 29.4 cm(-1)), and antiferromagnetic (J(2) = -4.6 cm(-1)) couplings and an average g = 2.05, corresponding to a ground state with three parallel and one anti-parallel spin for each Cu(2)NITpPy(2) unit. DFT calculations allowed assigning the ferromagnetic coupling to Cu-O-NITpPy and the antiferromagnetic coupling to Cu-N(Py)-NITpPy. Single crystal EPR spectra display only one resonance for most field orientations, as a consequence of the collapse of the signals of the different spins produced by the exchange interactions. The observed g-tensor of this resonance is related to those expected for the Cu(II) and radical ions. Comparison of this compound with other Cu-NIT radicals chains bearing different substituents in the organic radicals, highlights that the beta-diketonate ligand plays an important role in determining the final architecture. Moreover, we show how a knowledge of the spin density distribution in the initial building blocks is essential to rationalize the magnetic behavior of the resulting product.


Assuntos
Cobre/química , Compostos Organometálicos/síntese química , Polímeros/síntese química , Algoritmos , Cristalografia por Raios X , Espectroscopia de Ressonância de Spin Eletrônica , Magnetismo , Conformação Molecular , Compostos Organometálicos/química , Polímeros/química
3.
Inorg Chem ; 48(11): 4737-42, 2009 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-19466800

RESUMO

A structural and magnetic characterization of a trinuclear chiral Mn(II) formate three-dimensional framework exhibiting a triangular arrangement is presented. Compound Na(3)[Mn(3)(HCOO)(9)] was obtained by solvothermal synthesis and crystallizes in the chiral cubic space group P2(1)3 and is well described by a Delta conformation. The structure displays triangular Mn(3) building blocks, in which the metal centers are bonded by formate ligands in a syn-anti mode (Mn-Mn 5.697(1) A). The coordination sphere of manganese(II) is completed by six oxygen atoms from six formate ligands, resulting in an octahedral geometry. Magnetic susceptibility measurements showed antiferromagnetic interactions at high temperature and a strongly field dependent magnetic behavior below 40 K. At fields higher than 1.0 kOe only the antiferromagnetic interactions can be observed. At applied fields lower than 1.0 kOe magnetic susceptibility becomes irreversible with maxima observed at 22 and 34 K. These maxima suggest a weak ferromagnetic behavior because of spin canting, allowed by the presence of the noncentrosymmetric syn-anti HCOO bridges linking the Mn sites. This non-collinear antiferromagnetism and irreversible behavior can be due to the existence of a high degree of frustration in this unique lattice composed of linked triangular arrangements of interacting magnetic centers.


Assuntos
Magnetismo , Manganês/química , Compostos Organometálicos/química , Compostos de Organossilício/química , Cristalografia por Raios X , Modelos Moleculares , Compostos Organometálicos/síntese química , Temperatura
4.
Estud. psicol. (Campinas) ; 5(1): 5-38, jan./jul. 1988.
Artigo | Index Psicologia - Periódicos | ID: psi-6408

RESUMO

O presente trabalho teve por objetivos: (1) levantar as forcas motivacionais que levam os Professores de Pos-Graduacao em Psicologia, no Brasil, a pesquisarem e publicarem; (2) analisar o que contribui para que alguns docentes nao publiquem e (3) caracterizar o docente nos nossos cursos de Pos-Graduacao em termos de idade, sexo, estado civil, numero de filhos, local de formacao etc. Quartoze dos 18 cursos contactados responderam ao questionario num total de 102 respostas. Verificou-se que 86 por cento deles publicaram no Brasil e pelo menos 35 por cento publicaram tambem no Exterior. Os fatores que, no geral, mais servem de incentivo para a publicacao de artigos sao: desejo de contribuir para o desenvolvimento da ciencia e de obter realizacao pessoal. Os professores que nao publicaram citaram falta de tempo e dificuldade de acesso a orgaos de publicacao, como as principais razoes.


Assuntos
Docentes , Psicologia , Pesquisa , Publicações , Motivação , Brasil , Psicologia , Pesquisa , Publicações , Motivação , Brasil
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