After many years of stagnant contraceptive prevalence intensive programming efforts appear to be paying off in Nigeria. The latest PMA2020 surveys based in 7 states estimate that modern method prevalence among married women increased nationally from 9.8% in 2013 (based on DHS data) to 16.0% in 2016. Such an increase of more than 2 percentage points per year is widely recognized as excellent performance. This is a two page snapshot of indicators from the first nationally representative survey sample in Nigeria. PMA / Nigeria is carried out in seven states: Anambra Kaduna Kano Lagos Nasarawa Rivers and Taraba. Two survey rounds have been completed in Lagos and Kaduna and one survey round has been completed in Nasarwa Rivers Taraba Kano and Anambra.

An actively cooled lower hybrid current drive (LHCD) launcher has been installed in 1999 in the Tore Supra tokamak. During the shots, the temperature of the antenna front part is measured with infrared cameras and on the back with thermocouples. The energy removed by the cooling water loop is also recorded. The infrared analysis and the calorimetric balance sheet for plasma indicates that the temperature increase and the absorbed energy are higher than expected. The thermal measurements have been compared to finite elements calculations with the Cast 3M code taking into account the RF losses, the plasma radiated heat flux and an additional heat flux on the antenna and guard limiter surface in front of the plasma. This additional source is most likely attributed to the interaction of fast ions.

We used a cloned human cDNA probe homologous to the placenta chorionic gonadotropin β subunit (CGB) and to the pituitary luteinizing hormone β subunit (LHB) and Southern blotting techniques to analyse DNA from a series of rodent x human somatic cell hybrids for the presence of specific gonadotropin β subunit related sequences. Our results provide evidence for the assignment and linkage of the eight genes (or pseudogenes) coding for the β subunit of these glycoprotein hormones to chromosome 19. Moreover, we observed a strict concordance between the permissivity of mouse x man hybrid cells to enteroviruses (which is linked to the presence of specific cell receptors encoded by human chromosome 19) and the presence of CGB and LHB related sequences, thus confirming the localization of the structural genes for the β subunits on chromosome 19.

The frequency of 12 different mutations of the steroid 21-hydroxylase gene (CYP21) was investigated in 129 French patients affected by congenital adrenal hyperplasia (CAH) due to steroid 21-hydroxylase deficiency. Eighty-nine percent of the CAH chromosomes were characterized. The most frequent mutations were a C-G substitution in intron 2, the deletion of the CYP21 gene and a T-A substitution in exon 4 in the severe form of the disease, and a G-T substitution in exon 7 in the nonclassic form. The correlation between the genotypes and the clinical forms of the disease showed marked variation in the phenotype from a single genotype, suggesting that individual variation and undetected additional mutations on the same CAH chromosome accounted for the phenotype. In 65 informative meioses of CAH families, no de novo mutation was found.

This paper concerns the prediction of fetal Down's syndrome in pregnant women. Down's syndrome is the most common congenital cause of severe mental retardation. We elaborate two predictive functions of trisomy 21, combining maternal age and a maternal serum marker. We evaluated them by means of receiver operating characteristic (ROC) curves which give a representation of sensitivity and specificity of a prediction model when varying the cutoff of the predictor on the whole spectrum. Since normal statistical methods for comparison of ROC curves rely on distributional assumptions which were not verified, we used bootstrapping of ROC curves as a check for the statistical significance of differences between the areas under the curves.

A prospective study of maternal serum human chorionic gonadotrophin (hCG) measurement for the selection of pregnancies with an increased risk of fetal trisomy 21 was undertaken in 24 000 pregnancies from 1 January 1989 to 31 December 1990. Maternal serum was sampled at 15-18 weeks of gestation. hCG was measured in one laboratory, with one technique. This 'hCG high level' technique was developed for this screening. Amniocentesis was offered to each woman with a maternal serum hCG level above the cut-off. The follow-up of the pregnancies is known in 92 per cent of cases. The combination of hCG values and maternal age gave a detection efficiency of 63 per cent for trisomy 21 with rates of amniocentesis of 30 per cent for patients aged 37 years, 20 per cent for patients aged 35 or 36 years, and 5 per cent for patients under 35 years of age. Based on this prospective study, an individual risk was calculated combining the serum hCG value and maternal age. Seventy-four per cent of trisomy 13, trisomy 18, triploidy, and 5p- deletion were detected either in the same selected group of women or in combination with ultrasonography performed when hCG values were very low. The follow-up study showed that women who had high or low hCG values represented a group at high risk for fetal or perinatal death.

In order to investigate the origin of mutations responsible for the fragile X syndrome, two polymorphic CA repeats, one at 10 kb (FRAXAC2) and the other at 150 kb (DXS548) from the mutation target, were analyzed in normal and fragile X chromosomes. Contrary to observations made in myotonic dystrophy, fragile X mutations were not strongly associated with a single allele at the marker loci. However, significant differences in allelic and haplotypic distributions were observed between normal and fragile X chromosomes, indicating that a limited number of primary events may have been at the origin of most present-day fragile X chromosomes in Caucasian populations. We propose a putative scheme with six founder chromosomes from which most of the observed fragile X-linked haplotypes can be derived directly or by a single event at one of the marker loci, either a change of one repeat unit or a recombination between DXS548 and the mutation target. Such founder chromosomes may have carried a number of CGG repeats in an upper-normal range, from which recurrent multistep expansion mutations have arisen.

Some 250 different mutations have so far been screened in the cystic fibrosis (CF) gene. The 50 nonsense, 33 splicing and 60 frameshift mutations are randomly distributed within the gene, unlike the 107 missense mutations or amino acid deletions. A large excess of missense mutations affects the exons encoding the first transmembrane (MS1) and first ATP-binding fold (NBF1) domains. Sixty-four of the 107 missense mutations may be classified as private, demic, local and general mutations on the basis of their geographic distribution in Europe. Private and demic mutations are randomly distributed within the gene; local and general mutations are not. It is well known that some RFLP markers are in linkage disequilibrium with some mutations. Private, demic and local mutations are randomly associated with each class of RFLP haplotypes. In contrast, general mutations, frequent and infrequent, are not randomly associated with RFLP markers. General mutations usually affect a specific part of the gene and are more likely to be associated with a specific RFLP marker. This suggests the existence of selective factors favoring these mutations, a hypothesis formerly postulated as a possible cause of the high frequency of the disease.

Maternal serum free beta (hCG) levels are elevated (median 2.20 MOM) in the first trimester of pregnancy in 38 Down syndrome cases as compared with appropriate controls. This observation may form the basis for its use as a marker in screening for Down syndrome in the first trimester. Altered levels of the free beta analyte are observed in pregnancy conditions or complications other than Down syndrome.

We have investigated the ultrasonographic signs that can help in the prenatal diagnosis of cystic fibrosis in 197 risk fetuses and compared them with 353 control fetuses. In 60 fetuses with a 1:4 risk for the disease, the gallbladder was also examined. All ultrasonograms were performed just before amniocentesis at 17-19 weeks of gestation. A previously described intra-abdominal hyperechogenic mass was found in 73% of the 48 affected fetuses, but 32 of the 149 unaffected fetuses also had this feature, giving a specificity of 77% and a sensitivity of 78%. When we investigated the gallbladder, we found 9 of the 12 affected fetuses to be without evidence of a gallbladder during the sonographic examination (none of the healthy or control fetuses had such a feature), giving a positive predictive value of 100%, a specificity of 100% and a sensitivity of 75%. The combined presence of an abnormal gallbladder and a hyperechogenic intra-abdominal mass yields the same positive predictive value and specificity, but does not improve the accuracy. Ultrasonography appears to be a good additional diagnostic tool for the prenatal diagnosis of cystic fibrosis, especially when the enzyme activities disagree. Furthermore, these results lead us to think that such a finding during routine ultrasonographic examination at 17-29 weeks could be a means of screening for cystic fibrosis. The absence of the gallbladder during the sonographic examination of fetuses at risk for cystic fibrosis at 17-19 weeks of gestation can help in the prenatal detection of the disease.

The sizes of the fragile X mutation in 33 sib pairs affected with fragile X syndrome were determined by Southern blot analysis. An age-dependent decrease in the size of the mutation was found, suggesting positive selection of blood cells carrying small mutations during life or maternal imprinting.

L'hCG est le meilleur marqueur sérique maternel permettant de définir un groupe de patientes présentant un risque accru de trisomie 21 fœtale. L'efficacité de ce dépistage dépend de plusieurs facteurs: 1) l'exacte détermination de l'âge gestationnel; 2) l'établissement des valeurs normales de l'hCG au cours du 2e trimestre de la grossesse; 3) la définition des valeurs seuils au-delà desquelles la réalisation du caryotype fœtal sera proposée à la patiente et 4) la technique de dosage de l'hCG. En nous basant sur une étude comparative portant sur neuf trousses de dosage d'hCG, nous étudions ce dernier point et montrons que certaines trousses de dosage mises au point pour le diagnostic précoce de grossesse (adaptées à la mesure des valeurs basses d'hCG) présentent une dispersion importante dans les valeurs hautes, rendant leur utilisation délicate pour le dépistage de la trisomie 21 fœtale.

Eleven complete Spanish pedigrees with fragile X syndrome were analysed by Southern blotting with the DNA probe StB12.3 previously isolated and described by Oberlé et al. [1991]. This probe allowed the direct detection of affected males and carrier females and was able to distinguish between normal males and normal transmitting males (NTMs). One hundred and twenty three individuals were analyzed, 115 from the pedigrees and 8 from the general population. Five mosaic cases were found (4 males and one female) showing both the premutation and the full mutation. One half of the females with the full mutation were mentally retarded but no female with mental retardation carried the premutated pattern, suggesting that the absence of the full mutation in females is a very good criterion for pre-or postnatal diagnosis of normal mental status.

Chromosomal mosaicism occurs more commonly in prenatal diagnosis in chorionic villus sampling than in liveborn individuals. A German collaborative study on 9 000 prenatal diagnosis affords precise data on the incidence of mosaicisms, their types and the mechanisms involved during the first mitosis of the blastocyst and especially the frequence of ana-phase lagging. These mosaicisms lead to confined placental mosaicism with consequences on the development of a diploid embryo, to uniparental disomy, illustrated by recent observations of Prader Willi syndrome. A careful study of similar observations will enlarge this new chapter on the consequences of chromosomal anomalies on fetal development.

Summary We previously suggested that an activation defect of pancreatic proteolytic zymogens in newborns suffering from cystic fibrosis (CF) might contribute (by an adaptative‐like process) to the significant increase of the serum trypsin level observed in the disease at birth. To give support to this hypothesis we studied two pancreatic enzymes: trypsin 1 (IRT) and chymotrypsin A (IRChT) by noncompetitive enzyme immunoassays in amniotic fluids taken at 17–18 weeks of pregnancy. In normal fluids (102), the levels of the two enzymes were widely dispersed between 5 and 100 μ,g/L. A similar pattern was observed for the fluids with a 1 in 4 risk of CF with a normal outcome (24). In contrast, the levels of pancreatic enzymes in the fluids with affected fetus (40) were always below 45 μg/L for IRT and 55 μg/L for IRChT and most of them were under 20 μg/L for both enzymes. The molecular forms of IRT and IRChT in amniotic fluids were studied by gel filtration. In amniotic fluids with affected fetus, a major form of IRT was eluted in a position consistent with the elution of proteins around 25 kDa and two peaks of IRChT were eluted at 75 kDa and 25 kDa. These patterns are similar to those observed in normal serum when zymogens are present and are quite different from the patterns obtained by gel filtration of amniotic fluids with normal outcome. In normal fluids, the major form of IRT was eluted with a protein of higher molecular weight (–76,000) consistent with a complex of trypsin with α1‐proteinase inhibitor and an additional peak of IRChT (–14 kDa) was present, possibly corresponding to a degraded form of chymotrypsin. These data shows the absence of active pancreatic proteases in the intestinal fluid of CF affected fetus in opposite to their presence in normal fetus. This absence could lead to an increased synthesis of proteolytic enzymes at birth.