Genetics of resistance to soybean cyst nematode, Heterodera glycines ichione (Race 3), in a brazilian soybean population

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

Genetics of anthracnose panel canker disease resistance and its relationship with yield and growth characters in half-sib progenies of rubber tree (Hevea brasiliensis)

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

CLASSICAL DISTRIBUTION-FUNCTIONS DERIVED FROM WIGNER DISTRIBUTION-FUNCTIONS

A mapping which relates the Wigner phase-space distribution function associated with a given stationary quantum-mechanical wavefunction to a specific solution of the time-independent Liouville transport equation is obtained. Two examples are studied.

Hemoglobin and HFE gene polymorphisms in Brazilian populations in regions endemic for malaria

Our objective was to determine how the distribution of red blood cell diseases is related to malaria occurrence in north Brazil, a region endemic for malaria. We evaluated the incidence of two mutations in the HFE gene, H63D and C282Y, in two study groups: a control blood donor group, with no indication of malaria infection, and a group constituted of malaria patients of four states of the Amazonian region. The hemoglobin polymorphisms were obtained by HPLC and classical laboratory methodologies, and the two mutations in the HFE gene were assayed by PCR-RFLP. We found a high frequency of alpha thalassemia, but there were no significant differences between blood donors and malaria patients. There were also no significant differences in the frequencies of HbA(2); however, the frequency of HbF was significantly different in individuals with malaria from Para and Rondonia. The mean number of reticulocytes was significantly reduced in the blood donors from the northern region, suggesting an adaptive strategy of these populations to parasitic attack by Plasmodium. Most individuals were heterozygous for the H63D allele of the HFE gene in both study groups. In the blood donors group, the greatest frequency of the H63D allele was found in Caucasians of all the states. In the malaria patients group in Rondonia, there was a high frequency of the H63D allele among the non-Caucasians. In the other states, and in the malaria patients group, the H63D allele was the most frequent among the Caucasians. Based on our results, we suggest that the maintenance of polymorphism of the mutations in the gene HFE can be explained by selective factors other than malaria, or it is due to simple allelic oscillation and by the constant gene flow among the populations in Brazil.

NUCLEAR ALIGNMENT - CLASSICAL DYNAMIC-MODEL FOR THE U-238 U-238 SYSTEM

Dynamical properties of the U-238-U-238 system at the classical turning point, specifically the distance of closest approach, the relative orientations of the nuclei, and deformations have been studied at the sub-Coulomb energy of E(lab) = 6.07 MeV/nucleon using a classical dynamical model with a variable moment of inertia. Probability of favorable alignment for anomalous positron-electron pair emission through vacuum decay is calculated. The calculated small favorable alignment probability value of 0.116 is found to be enhanced by about 16% in comparison with the results of a similar study using a fixed moment of inertia as well as the results from a semiquantal calculation reported earlier.

CLASSICAL EQUIVALENCE OF LAMBDA-R-PHI-2 THEORIES

It is shown that the action functional S[g, phi] = integral d4 x square-root -g[R/k(1 + klambdaphi2) + partial derivative(mu)phi partial derivative(mu)phi] describes, in general, one and the same classical theory whatever may be the value of the coupling constant lambda.

Electrophoretic and chromatographic profile for S-like hemoglobin

Hemoglobin variants originate mainly by simple amino acid substitutions, the result of nucleotide sequence changes. Recently, the number of known abnormal hemoglobins has increased due to improvement in analysis methodologies; however, many laboratories are not prepared to correctly identify mutants. Hb S is a very well-characterized hemoglobin variant that varies in prevalence in different regions of Brazil. However, there is a type of Hb that presents electrophoretic migration in alkaline pH similar to Hb S, named S-like Hb, which can be incorrectly diagnosed; therefore, its frequency is underestimated. We obtained reference ranges for Hb S by HPLC, and we examined the electrophoretic and chromatographic profiles of S-like Hb. Hb Hasharon, Hb D-Los Angeles, Hb Korle-Bu, Hb Lepore, Hb D-Iran, Hb G-like, Hb Queens, Hb Montgomery, and Hb Q-India were found. Cases of association between two beta chain mutants were also found. Electrophoresis in alkaline and acid pH was utilized to initially screen these Hb variants, and globin chain electrophoresis at both high and low pH was performed to identify the globin chain mutant. Chromatographic analysis permitted the identification of the hemoglobin variant and also facilitated the quantification of these variants. Therefore, an association of classical laboratory diagnostic methodologies is fundamental for the correct identification of suspect Hb variants. The S and S-like hemoglobin profiles determined in this study will help in the diagnosis of these variants in health care services.