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The aim of this study was to compare the effects of cigarette smoking on biologic and rheologic tests, chiefly on the red blood cells (RBC) in measuring the deformability by the Cell Transit Analyser (CTA) and their aggregation by using an ultrasonic interferometry method based on A-mode echography allowed for the measurement of the accumulation rate of particles in a solid plate which is related to their sedimentation rate (Echo-Cell). Nine male smoker subjects with a high nicotine addiction measured by Fagerström questionnaire (> 8) and level of carbon monoxide (CM) in the breathed out air (> 20 ppm), have been compared with ten healthy no-smoker volunteers (CM < 3 ppm). One smoker has been eliminated of statistic evaluations because his glucose level showed a diabetes (10.5 mmol/l). A nailfold capillaroscopy performed in all subjects has eliminated the patterns of latent vasculitis or scleroderma. RBC and platelets counts, hemoglobin, ionogram, gamma GT, ASAT, ALAT, uric acid, total cholesterol and glucose levels were not significantly different between the two groups. On the other hand, in the smoker group, white blood cells count, serum triglycerides and especially fibrinogen values were higher than in the non-smoker's group. RBC sedimentation rate was normal in the two groups but was higher in smoker's group too. Without consumption of alcohol, the mean RBC volume was more important in smokers (91.9 +/- 1.2 versus 87.5 +/- 0.4, p = 0.003). Rheologic tests were more pathologic in smokers. The transit time or RBC by CTA was longer than in control group (1.6 ms +/- 0.02 versus 1.2 +/- 0.05, p = 0.0003). Echo-Cell technic showed a number and size of RBC aggregates more important with a rate of speed of accumulation higher than in the control group. These results demonstrated the toxic effects of smoking alone on blood toward a propensity for thrombotic status.

The erythropoietin (Epo) is a model of proteins expressed upon hypoxia, regulated at the transcriptional and post transcriptional levels. The Hypoxia Induced Factor (HIF-I) activates the transcription of genes which exhibit the Hypoxia Regulatory Element (HRE). In addition the mRNA is stabilized upon hypoxia, increasing the hormone synthesis. The Epo gene is a convenient reporter gene to develop gene delivery systems and the in vivo regulation of the transgene. The beta thalassemia and acquired chronic anemias may benefit from the Epo gene transfer and expression, if it becomes safe, tunable and inexpensive.

Fetal red blood cells are necessary for the antenatal diagnosis of hemoglobinopathies. Fetal blood may be obtained in utero, by amniocentesis or fetoscopy, from the 17th to the 20th week of pregnancy. At this time, biochemical techniques may detect bêta-thalassemia major (fetal synthesis of hemoglobin btaA chain totally absent or less than 2% and sickle cell disease (fetal synthesis of btaS chain, without any production of bêtaA chain). When fetal blood has been severely contaminated by maternal blood, purification techniques allow enrichment of the sample in fetal red blood cells by the elimination of adult reticulocytes which may lead to errors in diagnosis.

The binding and specific elution of Hb peptides from Hp was studied. Our results were confirmed by the study of inhibition of binding of alpha chains to Hp. In conclusion, a model of contact areas of Hp-Hb complex is proposed.

From now on antenatal diagnosis of haemoglobinopathies is possible. Fetal blood can be taken from the uterus from the 17th to the 20th week of the pregnancy by direct puncture of the placenta or placentocentesis or by selective puncture of a straight vein close to its insertion in the cord on the fetal surface of the placenta, using a fetoscope. Biochemical techniques today allow us to detect beta thalassaemia major (with total absence of synthesis or with synthesis of less than 2 per cent of the beta A chain of haemoglobin by the fetus) and drepanocytosis (which is the synthesis of the chain beta S by the in the absence of production of the chain beta A). It is possible in cases where the fetal blood that has been taken is seriously contaminated by maternal blood (which is often the case with direct punctures) by using purification methods to increase the proportion of fetal red blood cells in the sample by eliminating adult reticulocytes which could cause errors in diagnosis. There are several centres where this type of diagnosis is being carried out. Some of them now have two years' experience and their results are encouraging. In spite of their difficulty these methods of investigation can allow couples at risk to have normal children or heterozygous infants. They can help them to avoid the need for termination of pregnancy or permanent contraception.

The filtration time of a small volume (0.1 ml) of red cell suspension from normal (AA), heterozygous (AS) and homozygous (SS) subjects for sickle cell disease was investigated as a function of PO2 The curve of filtration time of AS and SS red cell suspensions was biphasic. At high values of PO2, the progressive reduction of filtrability of sickle cell suspensions with decreasing PO2 occurred without new change in morphology of most of the cells. In contrast, at lower PO2 the apparent filtrability was improved and the cells were sickled." However the red blood cells were retained by the filter and the "solvent" filtrability was improved because rigid and highly deformed sickled cells did not clogged completely the pores of the filter. This study allowed to distinguish a new concept of apparent filtrability for red blood cells in sickle cell disease.

The incidence and nature of haemoglobinopathies were investigated at birth in Martinique, where 4635 samples of umbilical cord blood were examined. Conventional blood values were determined, and a new, extremely simple and highly selective test was performed: isoelectric focalization. Abnormalities were found in 14.3% of blood samples, viz: A/S 7.25%, A/C 3.17%, S/S 0.17%, S/C 0.24%, C/C 0.04%, other mutations 0.63% alpha-thalassaemia minor (alpha 1-thal) 1.72% and isolated microcytosis 1.01%. Unusual abnormalities included 7 different mutations of the 4a-chain, 3 of the beta-chain and 3 of the gamma-chain. The clinical and epidemiological importance of such investigations is emphasized.