Testing for Partial RhD with a D-Screen Diagast Kit in Moroccan Blood Donors with Weak D Expression.

The aim of this study was to search for the partial D phenotype in Moroccan blood donors with weak D expression. The study included 32 samples with weak D phenotype, and partial D category red blood cells were detected with the D-Screen Diagast kit, which consists in 9 monoclonal anti-D antibodies specific for the most common categories of partial D. Among the 32 samples studied, we identified 13 specific reactions to a partial D antigen (3 DVI, 2 DVa, 2 DIII((a,b,c)), and 6 DVII), with 8 reactions suggesting a weak D and 11 reactions providing no formal argument in favor of a partial D antigen. This work can be used to validate the performance of the anti-D reagent and to improve the safety of transfusion of red blood cells from donors expressing the partial D antigen by integrating the finding into the recipient file with a recommendation concerning the appropriate care.

Molecular defects in Moroccan patients with ataxia-telangiectasia.

Ataxia-telangiectasia (AT) is a rare autosomal recessive disease, affecting neurologic and immune system. Numerous mutations are described in the ATM gene in several populations. However, in Morocco, few data are available concerning this condition. Our main goal is to determine clinical, immunological, and molecular presentation of Moroccan patients with AT. We screened 27 patients, out of 22 unrelated families, for ATM gene mutations. All our patients showed ataxia, ocular telangiectasia, and immunodeficiency, as well as elevated serum alphafetoprotein levels. Mean age at diagnosis was 5.51 years, and consanguinity rate was 81.8 %. Mean age at onset was 2.02 years, and mean time to diagnosis was 3.68 years. We found 14 different mutations in 19 unrelated families, of which 7 were not reported. Our results showed that c.5644C>T mutation was the most common in our series. However, further studies are required to demonstrate a founder effects on ATM gene in Moroccan patients, who showed mutational heterogeneity otherwise. Our data indicate that direct sequencing of coding exons is sufficient for a high detection rate in ATM in Moroccan population.

[Flow cytometric DNA analysis and cytology in diagnosis and prognosis of bladder tumors: preliminary results of a comparative study of bladder lavage]. / Contenu en ADN par cytométrie en flux et cytologie dans le diagnostic et le pronostic des tumeurs vésicales: résultats préliminaires d'une étude comparative sur lavage de la vessie.

OBJECTIVE: To compare flow cytometric data (ploidy and proliferative activity or percentage SG2M-phase cells) to cytologic and histologic data of the bladder carcinomas. MATERIALS AND METHODS: Cytologic and flow cytometric analysis of DNA content were performed on 48 bladder washings: 28 bladder washings from patients being followed for urothelial carcinomas and 20 control washings from individuals undergoing cytoscopy for other reasons. RESULTS: Cytological sensitivity and specificity of bladder washing were 75% and 91% respectively. Specificity was increased to 94% using flow cytometric DNA analysis whereas sensibility was moderately decreased to 68%. Combination of flow cytometry and cytology increased the diagnostic yield to 100%. The study of the patient group showed an increased abnormalities (aneuploidy and/or proliferate activity SG2M > 10%) according to the tumor grading and tumor staging. A cytometric test was positive in 80% for G3 tumours and in 68% for G2 tumours. The staging tumor was positive in 46%, 89% and 100% of the pTa-pT1, pT2 and pT4 tumours respectively. Otherwise the comparison of control group with patients showed a statistical correlation between cytometric test, staging tumour and tumoral grading as showed in the following groups: control/G1-G2 (p < 0.05), control/G3 (p < 0.001), control/pTa-pT (p < 0.05), control/pT2-pT4 (p < 0.001). CONCLUSION: We confirmed through this study the interest of the flow cytometric DNA analysis in the diagnosis and prognosis of bladder carcinomas, and we showed the importance of the histogram classification in order to facilitate their interpretation and to avoid the trap of false aneuploidy.

Discrepancies of DNA content of various solid tumours before and after culture measured by image analysis. Comparison of cytogenetical data.

Parallel cytophotometric ploidy studies and cytogenetic analysis were performed on 15 various human solid tumours. The quantification of DNA by image analysis was carried out on cytological imprints of fresh tumours and on smears obtained after cell culture. The results obtained by both sets of calculations were compared with each other and with the cytogenetic results. 6 cases (40%) showed concordance between the 3 techniques. One case was aneuploid for both DNA image analysis measurements but the cytogenetic data showed only a diploid stem line. In 3 cases out of 15 (20%), smears DNA analysis and cytogenetic results were concordant: in 2 tumours, the culture step failed to preserve aneuploid stem lines that were present in the imprint analysis. In the third one, a minority tetraploid peak observed after culture was absent on the imprint slide. Concordance between imprints and cytogenetic data and discordance with smears' analysis was observed in 3 cases (20%). These 3 cases were diploid or near diploid but the DNA analysis on the smears after culture showed an aneuploid stem line in each case. The last 2 cases showed a total disagreement between the 3 techniques. By measuring the DNA content with an image analyser, the observer can ensure that only tumoral cells are taken into account. The present study revealed that cytogenetic data represent only about 60% of the population that is effectively present in the culture dish and that the cultured population represents only 47% of the population present on the fresh tumour imprint.