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Biomedical subjects

P Colonna

Publications and source records attributed to P Colonna.

At least 109 records · Page 6Linked to original sources
PubMed1984

Indirect evaluation of a gene frequency: calculation of beta-thalassemia frequency in Algeria based on associated hemoglobin variants frequency.

The gene frequency (q) of beta-thalassemia (T) is more difficult to evaluate directly than the frequency of hemoglobin variants (V), Hb S and Hb C being the most frequent ones in Algeria. Among 150 subjects with a phenotype V, we identified 76 compound heterozygotes VT(0) (T(0) = beta(0)-thalassemia) and 74 homozygotes VV: qT(0) is therefore practically equal to qV. Calculation based on the investigation of 54 subjects detected during the same period (33 VT among which 23 VT(0) and 21 TT among which 9 T(0) T(0) yields qT = 1.43 qT(0) = 1.43 qV. According to Cabannes [1965], qV is equal to 0.0113, qT is 1.43 X 0.0113 = 0.0162. This indirect method, based on investigation of patients, gives a less precise evaluation of gene frequency than a direct method based on large population screening. This evaluation, however, is sufficient to estimate the incidence of beta-thalassemia and its impact from a public health point of view.

Algeria↗
PubMed1983

[Comparative double-blind study of Bi-Profenid and oxyphenbutazone in sports pathology].

Effectiveness and tolerance of ketoprofen in sustained-release tablets (Bi-Profenid 150 mg) were investigated in a double blind trial in 44 athletes who had recently sprained an ankle. Patients were given either 300 mg Bi-Profenid or 400 mg oxyphenbutazone daily for seven days. Treatment regimens were assigned at random. Results were assessed as excellent or good in 85% of patients given Bi-Profenid and 50% of those given oxyphenbutazone. Spontaneous pain resolved in 19 patients receiving Bi-Profenid and in 6 under oxyphenbutazone. Decrease in pain upon physical examination and in articular circumference was significantly greater with Bi-Profenid as compared with oxyphenbutazone. The chance of rapidly resuming sport was better with Bi-Profenid. Tolerance was excellent in 68.2% of patients with Bi-Profenid and 59% of those with oxyphenbutazone. This investigation thus emphasizes the value of Bi-Profenid in sport pathology.

Adolescent↗
PubMed1983

Chronic lymphocytic leukemia in Maghreb and Europe. A comparison between Algiers and Amiens from 1966 to 1976.

The frequency of chronic lymphocytic leukemia (CLL) varies a great deal from one population to another. We have undertaken to compare the aspects of CLL in Maghreb and Europe through two series of comparable importance, studied during the same period and under similar conditions in Algiers and Amiens. This comparison shows, in Algeria, a lower frequency, a very marked male predominance, a high proportion of patients with a normal or high rate of gammaglobulins and an almost complete lack of hypogammaglobulinemia. Demographic (compared structure of populations), technical (medical density, availability of laboratory examinations), and ethnic (rarity of CLL in some populations) factors are to be taken into consideration in explaining these differences.

Adult↗
PubMed1983

[Multiple lentiginosis and hypertrophic obstructive cardiomyopathy].

Two patients with Multiple Lentiginosis (ML) had hypertrophic cardiomyopathy with severe obstruction of the right and left ventricular outflow tracts. ML is a rare syndrome in which there is a typical skin pigmentation disorder together with various other abnormalities like slight mental retardation, sensorineural deafness, genital and skeletal anomalies and sometimes a characteristic facies. Obstruction of the right ventricular outflow tract is frequent in such patients. The association of ML and obstructive hypertrophic cardiomyopathy has been recently reported. A critical examination of the literature in addition to our clinical observations suggests that the biventricular obstructive hypertrophic cardiomyopathy may play a major role in the clinical feature of ML syndrome.

Cardiomegaly↗
PubMed1982

Kinetic alterations of the red cell membrane phosphatase in alpha- and beta-thalassemia.

We studied the red cell membrane neutral phosphatase, which is part of the Na+K+ ATPase, in several types of oxidative hemolytic anemias. We used an artificial substrate, the p-nitrophenylphosphate. In controls and in patients heterozygous for various unstable hemoglobins (Hb Hope, Hb Köln, or Hb Hammersmith), the kinetics were of the Michaelis-Menten type. On the contrary, in nearly all patients with alpha- or beta-thalassemia, the kinetics displayed an abnormally biphasic character. The apparent Michaelis constant (KMapp) was significantly decreased. The biphasic character correlated with the imbalance of globin chain synthesis. The beta-mercaptoethanol markedly increased Vmax in controls, but had little effect on the biphasic kinetics. Omission of K+ abolished the biphasic kinetics. The abnormal kinetics failed to appear with another artificial substrate, the 4-methylumbelliferylphosphate, nor did it appear with ATP, the natural substrate. In vitro, H2O2 treatment of normal and thalassemic red cells was unable to induce or exaggerate, respectively, the biphasic kinetics, but generated alterations of a different nature. We suggest that the various kinetic alterations of the phosphatase in thalassemic syndromes originate from the imbalance of globin chain synthesis. However, the involvement of an oxidative process remains to be demonstrated.

Erythrocyte Membrane↗
PubMed1981

Hemoglobin H disease from Algeria: genetic and molecular characterization.

A case of Hb H disease from Algeria was studied at the genetic and molecular level in order to delineate the pattern of alpha-thalassemia in the Mediterranean population. The family study indicated that both parents had the hematological and clinical manifestation of alpha-thalassemia trait and that the affected sibling had homozygous alpha-thalassemia with 5.6% Hb H, microcytosis and an alpha-/non-alpha-biosynthetic ratio of 0.64. Hybridization in globin cDNA alpha excess suggested that the molecular defect responsible for this form of alpha-thalassemia is a partial deletion of the haploid stock of alpha-globin genes. The Algerian case of Hb H disease studied thus differs from Asian and Negro cases by the mode of inheritance of the alpha-thalassemia mutation involved.

Adult↗
PubMed1981

Hemoglobin Bart's in Northern Algeria.

The hemoglobin patterns of 293 cord bloods from Northern Algeria were examined by electrophoresis on cellulose-acetate strips. A fast-moving component, identified as Hb Bart's, was found in about 10% of the cases. The levels of Hb Bart's ranged from 0.1 to 10% of the total hemoglobin. There was a significant correlation between the Hb Bart's levels and the decrease in MCV. The relative rates of globin chain synthesis measured by 3H-leucine incorporation was estimated in 15 cord bloods. It was found imbalanced in the 5 cord bloods which contained more than 0.5% Hb Bart's. These findings suggest that elevated Hb Bart's levels in the Algerian population are due to the presence of alpha-thalassemia.

Algeria↗
PubMed1980

Heterogeneity in beta 0 thalassemia from Algeria: genetic, clinical and molecular studies.

Six Algerian patients with beta 0 thalassemia are presented, in addition to the two patients already reported (Godet et al., 1977). Family studies indicate that all the patients had homozygous beta thalassemia characterized by absence of beta globin chain synthesis in peripheral blood. The clinical severity varies from one family to the other and within the same family, from typical Cooley's anemia to thalassemia intermedia and appears to be related to the child death rate observed in each family. The gamma/alpha biosynthetic ratio was 0.36-0.40 in seven patients and 0.2 in the most seriously affected patient. The mRNA beta content in peripheral reticulocytes was less than 1.5% of mRNA alpha in seven patients and 13.3% in one patient. These results indicate that Algerians homozygous for beta 0 thalassemia are heterozygous at the clinical, biochemical and molecular levels.

Adolescent↗
PubMed1980

Significance of bone-marrow scintigraphy in aplastic anemia: concise communication.

Tc-99m colloid and In-111 transferrin were used in a semiquantitative scintigraphic study of bone-marrow activity in 76 patients with aplastic anemia, the majority of which were severe cases. The results are compared with other known prognostic parameters and with a predictive index formulated from a prior multi-parametric analysis performed in 352 cases. In 47 cases parallel abnormality of Tc and In uptakes was noted and was well correlated with other prognostic factors. Indium uptake is apparently a good indicator of the severity of aplasia; extension of active erythroid tissue, demonstrated with this method, is correlated with prognosis. In nine cases, excessive In uptake is explained by dyserythropoiesis associated with granulo- and thrombocytopenia (Fanconi's anemia in most cases). In 20 of our patients, TcSC uptake was excessive compared with that of In and with other prognostic factors. Statistically, this phenomenon carries an unfavorable prognosis but its physiological meaning remains to be defined.

Anemia, Aplastic↗
PubMed1978

[Double medular scintigraphy using 99mTc-colloids and 111In-transferrin in myeloid splenomegaly (author's transl)].

Simultaneously with bone marrow biopsy and 59Fe kinetic study, bone marrow scintigraphy using 99mTc-colloids and 111In-transferrin was performed in 15 patients with a documented diagnosis of agnogenic myeloid metaplasia. This rapid, simple and non-traumatic method permits visualization of changes in the reticular and the erythropoietic marrow which are not always the same. The technique can demonstrate diminution of active marrow in the axial skeleton, peripheral extension of bone marrow and its heterogeneity from site to site. These abnormalities, which vary from case to case, correlated well with the results of 59Fe external countings. The degree of splenic myeloid metaplasia, as judged by 111In uptake, is also well correlated with 59Fe uptake into the spleen. There was poor correlation between scintigraphic and iron kinetic data on the hand, and bone marrow cellularity assessed by marrow biopsy on the other. While scintigraphic studies are chiefly qualitative, they appear to provide useful information for diagnosis, and possibly for prognostic and therapeutic decision.

Aged↗
PubMed1978

[Recording of the right atrial monophasic action potential in humans. I. Subjects not affected by arrhythmia].

Using a bipolar suction electrode technique, right atrial monophasic action potential (RA MAP) was recorded in 18 patients surely free from any kind of arrhythmia. Two morphologically different kinds of RA AMP were obtained: the former exhibiting an evident transition between phase 1-2 (plateau) and phase 3 of repolarization (FP), the latter without any appreciable palteau (FL). Electrophysiological properties of human myocardial atrial tissue have been investigated by microelectrode technique. The two types of MAP recorded by us resemble the former the action potential obtained from conducting specialized fiber, the latter the action potential of contractile fibers. A statistically significant difference in RA MAP duration measured at 90% level of repolarization (D 90%) was found between the two kinds of MAP: therefore we suggest to perform quantitative evaluations and pharmaco-ogical investigations only including MAPs of similar morphology. The intraindividual variation coefficient of D 90% may be considered an expression of the range of variability of repolarization duration in man; we suggest that only MAPs of similar configuration should be accepted for its calculation in order to avoid errors of evaluation.

Action Potentials↗