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P C Naoum

Publications and source records attributed to P C Naoum.

13 recordsLinked to original sources

[Age and racial geographic distribution of S hemoglobin in Brazil].

OBJECTIVES: This paper was meant to analyse distribution of HbS carriers in Brazil, comprising its regional prevalence and the relationship with racial settlement and age groups. MATERIAL AND METHODS: 67,667 blood samples from 48 Brazilian towns were analysed from 1976 to 1988. Such samples were classified as Caucasoid and Negroid. The diagnosis was defined by means of qualitative electrophoresis in alkaline and acid pH, quantification of haemoglobin fractions, cytological studies and some cases were confirmed after examination of the parents. RESULTS: The study of those 67,667 samples allowed us to detect 1,492 HbS carriers (2.2%). That frequency is higher among Negroids (5.16%) than among Caucasoids (1.22%): Z = 22.1397 (Zcritical; 0.05 = 1.9600). Taking the HbS carrier distribution into consideration, we noticed that it is relatively homogeneous among Negroids and higher than 5% in 9 out of the 16 areas involved in the study. By classifying the age group of the areas in the general sample and by comparing the proportions, we found out that there are significant differences (chi 2 = 50.88; chi 2 critical; 0.05; 5 gl = 11.070). CONCLUSIONS: Sickle-cell anaemia diseases play an important role among the pathologies found in several countries, including Brazil. This paper shows that the carriers prevalence varies in the several areas under study and is higher among Negroids in almost all of them. The decreasing frequency occurring from North to South in the general samples and among Caucasoids may be assigned to the contribution of the Negroes in the interracial crossing, particularly in the Northeast.

Age Distribution↗

Serum haptoglobin types in patients with hemoglobinopathies.

Haptoglobin types were determined in 626 individuals living in the State of São Paulo (Brazil). Of these, 484 had Hb AA, 31 major beta thalassemia, 43 minor beta thalassemia, 14 Hb SS, and 54 Hb AS. Frequency distribution of the three most common types observed among patients with type beta thalassemia differed significantly from that observed in the Caucasian group with Hb AA. There was a significant increase in Hp 1-1, which led us to assume that these disorders participate in a selective process acting on haptoglobins and altering the equilibrium of their frequencies. This relationship was not observed when we compared patients with Hb SS and Hb AS with Black patients with Hb AA, although the type most often observed among patients with Hb SS was Hp 1-1. The distributions of Hp groups observed among Caucasian and Black patients with Hb AA were similar to those obtained by other investigators for the South and Southeast regions of Brazil, with the exception of Rio de Janeiro.

Alleles↗

An improved electrophoretic method for a screening program for haemoglobinopathies.

A method for a screening program for haemoglobinopathies in a starch agar gel mixed with saponin is presented. Normal and abnormal blood containing haemoglobins S, C, I, M Boston, D Punjab, beta thalassaemia major and beta thalassaemia minor, were applied, in a tray with the capacity for 100 samples. The electrophoresis was performed in 45 min using 300 V. This method offers special advantages for the examination of a large number of samples, using a small amount of whole blood and without the previous preparation of haemoglobin solution.

Electrophoresis, Agar Gel↗

[Laboratory investigation of hemoglobinopathies (author's transl)].

The importance of the haemoglobinopathies, mainly thalassaemia, as a public health problem has been emphasized. The establishment of methods for detection and diagnosis of haemoglobinopathies is the major step in laboratories dedicated to screening anemias. Tables for the diagnosis of alpha and beta thalassaemia are proposed, the methods to identify abnormal haemoglobins are discussed and a map with the relative mobilities of 115 abnormal haemoglobins by electrophoresis in alkaline buffer is shown.

Blood Protein Electrophoresis↗

Simultaneous occurrence of Hb C trait and polycythaemia vera.

A slow abnormal haemoglobin was found in a 27 year-old Negro man who had polycythaemia vera. Chemical and structural analysis showed it to be Hb C. The oxygen affinity showed a normal P50 value. Clinical and haematological investigations are described and discussed.

Adult↗

The denaturation of human oxyhaemoglobin A, A2 and S by isopropanol/buffer method.

Human oxyhaemoglobin A and A2 from normal individuals and oxyhaemoglobin S from patients with sickle cell anaemia and sickle cell trait were studied using Isopropanol/buffer method at 37 degrees C and 40 degrees C. Hb S was less stable than Hb A, whereas Hb A2 was considerably more stable than either. Denaturation of Hb S was dependent on temperature and its concentration. Between the patients with sickle cell trait it was not possible to verify the influence of the concentration probably due to the small range used (from 38% to 44%).

1-Propanol↗

Detection of haemoglobin D Punjab in patient with Sydenham's chorea.

In the present report the authors identified a rare haemoglobin, Hb D Punjab, in association with Sydenham's Chorea. They emphasize the importance of characterizing unusual haemoglobins by peptide mapping, particularly when the electrophoretic pattern shows the characteristics of known haemoglobins and when associated with pathologic states.

Acute Disease↗

Oxygen toxicity and hemoglobinemia in subjects from a highly polluted town.

Red blood cell activities of superoxide dismutase and glutathione peroxidase, two key enzymes responsible for the control of the concentrations of activated oxygen species, were approximately two-fold higher in residents of Vila Parisi (Cubatão, Brazil)--a higher polluted neighborhood--than in a population sample from São Paulo City. The catalase levels were the same in both samples. A concurrent high concentration of methemoglobinemia and sulfhemoglobinemia was encountered in the blood of Vila Parisi residents. These data raise the possibility that the increased rate of oxyhemoglobin oxidation yielding O-.2 and H2O2 may be relevant to mutagenesis induced by HO. radicals.

Adolescent↗