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T Henni

Publications and source records attributed to T Henni.

30 records · Page 2Linked to original sources
PubMed1987

Alpha-thalassemia haplotypes in the Algerian population.

DNA mapping was performed in seven unrelated Hb H patients and nine carriers for alpha-thalassemia trait originating from Algeria. This study has allowed us to identify four alpha-thalassemia haplotypes: the (-alpha 3.7) haplotype, which is the most frequent (18 of 23 alpha-thalassemic chromosomes), the (-(alpha)20.5) haplotype, a (--) haplotype, and an (alpha alpha)T haplotype. Our results also show that the (-alpha 3.7) haplotypes encountered in the Algerian population are heterogeneous and differ by the site of the unequal crossover responsible for the 3.7-kb deletion and the size of the interzeta fragment. In addition, during this survey we observed that normal chromosomes bearing a polymorphic BglII site are associated with different interzeta fragments.

Algeria↗
PubMed1987

Mixed blood chimerism in T cell-depleted bone marrow transplant recipients: evaluation using DNA polymorphisms.

We have used DNA sequence polymorphism analysis to document engraftment after T cell-depleted bone marrow transplantation (BMT), with a selected panel of four DNA probes. In contrast to nondepleted BMT recipients, the patients who received T cell-depleted marrow exhibited a mixed blood chimerism. This mosaicism was observed before graft failure or relapse in six patients. However, in five other patients, this mixed chimerism was not followed by these complications with a follow-up of 9 to 31 months after transplantation. Our results support the hypothesis that transplanted bone marrow T cells may help to maintain engraftment by eliminating host cells that can cause graft failure.

Adult↗
PubMed1985

alpha-Thalassaemia associated with the deletion of two nucleotides at position -2 and -3 preceding the AUG codon.

The nucleotide sequence of three single alpha-globin genes resulting from a rightward 3.7-kb deletion is described. The alpha genes were isolated from the DNA of three subjects homozygous for this deletion, the first being in addition homozygous for the structural mutation alpha G Philadelphia (genotype -alpha G/-alpha G), the second, heterozygous for this structural mutation (genotype -alpha A/-alpha G) and the third homozygous for an alpha + -thalassaemic gene (genotype -alpha +thal/-alpha +thal). The latter subject produced HbH in contrast to the two others. Whereas the two alpha A and alpha G genes are identical to the normal alpha 1-globin gene (except for the alpha G point mutation), the alpha +thal gene has (i) a deletion of the two nucleotides at position -2 and -3 preceding the ATG codon, and (ii) a fusion between the 5' part of the normal alpha 2 gene and the 3' part of the normal alpha 1 gene. Using a dot-blot assay, we show that reticulocytes from the HbH subject contain at least as much alpha mRNA as reticulocytes from the two other subjects. In a transient expression system, the alpha +thal gene leads to normally spliced transcripts. We conclude from these data that the defective output of alpha chains by the alpha +thal gene, as evidenced by HbH production, results from a decreased efficiency of alpha-mRNA translation due to the two nucleotides deletion preceding the AUG codon.

Base Sequence↗
PubMed1985

Red cell kinetics in thalassaemia intermedia: its use for a prospective prognosis.

A kinetic study of erythroid cell production and destruction (radioactive iron incorporation, red blood cell survival time, bone marrow scintigraphy) was performed in 12 cases of thalassaemia intermedia (six adults and six children), classified retrospectively, and compared to that performed in 17 cases of Cooley's anaemia. Our results confirm the genetic heterogeneity of these cases, the level of Hb F varies from 30% to 100% and the non alpha/alpha chain synthesis is only statistically superior to that seen in Cooley's disease. On the other hand, the kinetic study clearly separates the cases who are, or will be, clinically intermediate, showing a higher radioactive iron medullary uptake, a less ineffective erythropoiesis than that seen in Cooley's disease, and a greater peripheral haemolysis. In our study, no overlap was seen between the two groups. Iron kinetic study is then of prognostic interest and may help in therapy decisions, transfusion regimen and iron chelation, and splenectomy.

Adolescent↗
PubMed1985

Alpha globin gene triplication in severe heterozygous beta thalassemia.

In an Algerian family, three sibs with an unusually severe heterozygous beta-thalassemia and two sibs with a typical heterozygous beta-thalassemia were found. Both conditions were transmitted vertically. Globin chain synthesis and DNA restriction enzyme analysis showed that the unusual severity of heterozygous beta-thalassemia observed in this family is related to an overproduction of alpha-globin chains originating from an alpha-globin gene triplication.

Adolescent↗
PubMed1984

Sickle cell beta-thalassaemia compared with sickle cell anaemia in Algeria.

Clinical, haematological and biochemical features in 42 subjects with S-beta thalassaemia (31 subjects with S-beta thalassaemia and 11 subjects with S-beta+ thalassaemia); and in 42 with homozygous sickle cell disease were compared. Persistent splenomegaly was more common and painful crises less common in the S-beta thalassaemia group. Total Hb was higher and reticulocyte count lower in S-beta+ thalassaemia than in S-beta thalassaemia or SS disease. Microcytosis was marked in the S-beta thalassaemia group while the MCV was normal in sickle cell anaemia. Hb F was significantly higher in the S-beta thalassaemia group, without any influence on the severity of the disease. Many features suggest that sickle cell thalassaemia is more severe in Algeria than in Negro subjects and similar to the disease in Italian patients.

Adolescent↗
PubMed1983

Beta thalassemic mutations recognized by DNA mapping with Hph I and Rsa I in the Algerian population.

By using Hph I and Rsa I restriction enzymes and beta globin large intervening sequence as a probe, we have investigated the DNA of 20 Algerian patients with beta(0) or beta(+) thalassemia. In any of them, we detected the nucleotide change which is known to generate an additional Hph I site at the 5' splice junction of the beta globin large intervening sequence and which yields a beta(0) phenotype. In one of them, we detected the nucleotide change which is known to generate an additional Rsa I site within the beta globin large intervening sequence and which is supposed to yield a beta(+) phenotype. These results indicate that these two types of mutation are relatively rare in the Algerian population.

Base Sequence↗
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

Mapping the alpha-globin genes in an Algerian HbH patient and his family.

The organization of alpha-globin genes in normal white European, normal Algerian, and alpha-thalassemic Algerian DNA was examined by restriction endonuclease mapping using HindIII, HpaI, Bamhi, EcoRI, BgIII, and PstI. The results for normal DNA confirm and add to the findings of Surrey et al. and Orkin; the two alpha-genes are approximately 3.0 kb apart. The restriction enzymes BgIII and HpaL cut between the two alpha-genes. Four PstL sites are located: two surrounding each alpha-gene. The physical maps for a number of Algerian controls (normal alpha- and beta-globin biosynthesis profiles) are identical to that of the European controls. The Algerian alpha-thalassemic presenting with HbH disease was found to be homozygous for a 3.5-3.7 kb deletion at the alpha-gene locus, leaving one alpha-gene per chromosome. The patient's mother and father are both found to be heterozygous for this deletion. An unaffected sibling carries both normal chromosomes. The deletion could be the result of a Lepore-like crossover fusion event between the two alpha-globin genes, or of a 3.7 kb deletion of either the entire 5' alpha-gene or the entire 3' alpha-gene. The Algerian case of HbH disease studied differs from Asian cases in both the mode of inheritance and the molecular pathology of the alpha-thalassemia mutation. If this type of deletion is the major cause of Algerian alpha-thalassemia, it would explain the apparent absence of Hydrops fetalis in this geographical area.

Algeria↗