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M Alkan

Publications and source records attributed to M Alkan.

At least 73 records · Page 4Linked to original sources
PubMed1990

Haplotype analysis for CF-linked DNA polymorphisms in Switzerland.

A total of 295 patients, parents and unaffected sibs from 106 CF-families in central and northeastern Switzerland were investigated with probes 7C22(D7S16), metH, metD, pKM19, pXV-2c and pJ3.11(D7S8) for eight DNA polymorphisms (RFLP's). Linkage disequilibrium to the CF locus and haplotype frequencies were compared to those in other populations. They are comparable to other Caucasian populations and, for pKM 19 and pXV-2c, very close to the findings in Italy. The prevalence of certain haplotypes among the CF and the normal allele-bearing chromosomes indicate that the majority of the CF cases are probably the result of one ancient mutation in a common ancestor, but that there may be allelic heterogeneity accounting for an important proportion of patients, that may differ between countries or regions. Informative family constellations for the different polymorphisms in Switzerland and strategies for carrier detection and prenatal diagnosis are discussed. Haplotype analyses for each country and its ethnic subgroups are recommended.

Chromosome Mapping↗
PubMed1990

Stimulation of oxidative burst in human monocytes by lipoteichoic acids.

Lipoteichoic acid isolated from Streptococcus faecalis or Streptococcus pyogenes caused direct activation of the respiratory burst in human peripheral blood monocytes. This activity appears to be related to the ability of lipoteichoic acid to bind to the monocyte membrane and trigger the polarization of receptors (capping).

Adult↗
PubMed1990

Host defense during pregnancy: monocyte adherence and killing.

Pregnant women are more susceptible to candida infections than nonpregnant women. Since monocytes play a major role in host defense against candida, their association with radiolabeled candida and their capacity for killing candida were compared in sera of pregnant and nonpregnant women. While the basal rate of these monocyte functions was similar in both groups of women, candida opsonized with serum from pregnant women was less effective in enhancing these monocyte activities. Serum from nonpregnant women increased the association about twofold, whereas serum from pregnant women increased it only by about one and a half times in the two groups of women. Pretreatment of candida with serum from pregnant women increased the killing to 28%, whereas the serum from nonpregnant women was more effective, increasing the killing to 40%. The difference between the effect of the sera could not be attributed to the level of serum complement or IgG.

Adult↗
PubMed1990

Doxycycline prophylaxis for shigellosis.

The efficacy of oral doxycycline, 100 mg/d for 14 days, in reducing the incidence of shigellosis in newcomers to an area hyperendemic for the disease was examined in a double-blind, placebo-controlled trial. Of 107 entrants, 100 completed the study; 50 received the drug and 50 received a placebo. Diarrheal disease and associated symptoms were monitored for 8 weeks. Starting on the 3rd day of the trial, an outbreak was observed, and Shigella flexneri type 2a was isolated from 6 subjects. Eight of the subjects in the treatment group had diarrhea (16%) compared with 37 in the placebo group (74%), providing a 79% protection rate. There was no significant difference in the occurrence of accompanying symptoms between the subjects suffering from diarrhea in both groups, but the duration of disease was shorter in the treatment group. Serologic study of the outbreak showed no significant difference in antibody response to S flexneri between the treatment (14 of 43) and placebo (18 of 39) groups. Doxycycline prophylaxis apparently is effective and probably does not prevent subclinical infection.

Adult↗
PubMed1989

[DNA diagnostics in hemophilia A and B].

Carrier detection and prenatal diagnosis of hemophilia A and B are possible with cloned factor-VIII:C- and factor-IX-gene-specific or linked probes which detect restriction fragment length polymorphisms (RFLPs). In this study, 12 hemophilia-A- and 5 hemophilia-B-families were studied to identify carriers and provide adequate genetic counselling to women who were heterozygous for one or more of the intragenic or linked DNA probes with respect to future pregnancies.

Adult↗
PubMed1989

Human peritoneal macrophage activity is increased by tuftsin.

Peritonitis caused by Candida albicans is a major complication of continuous ambulatory peritoneal dialysis (CAPD). Increasing the activity of the peritoneal macrophages--the predominant cell type found in the peritoneal cavity--may be of great importance in the prevention and therapy of peritonitis. Therefore, the activating effect of tuftsin was studied on human peritoneal macrophages from CAPD patients. Tuftsin induced a biphasic effect on macrophage activity within a range of 2 X 10(-9)-2 X 10(-6) M, with a maximal activity of 2 X 10(-7) M. At this concentration, tuftsin enhanced by twofold cell association with radiolabelled candida (from 2 +/- 0.2 to 4 +/- 0.2 candida per macrophage) and superoxide anion production in response to exposure to candida (from 150 +/- 20 to 300 +/- 20 nmoles/mg). These results suggest the potential use of tuftsin as a therapeutic drug.

Adult↗
PubMed1989

Detection of polymorphisms at cytosine phosphoguanadine dinucleotides and diagnosis of haemophilia B carriers.

The polymerase chain reaction procedure (PCR) was used to detect a polymorphic Hha I site adjacent to the factor IX locus in a panel of 33 phenotypically normal caucasian individuals. This technique was also applied to a haemophilia B family pedigree. The Hha I polymorphic site was located 8 kb 3' to the factor IX gene, and the proportion of female subjects expected to be heterozygous at this site was 0.48. The Hha I locus was in linkage equilibrium with the other polymorphic loci on the factor IX gene. These findings, besides increasing the proportion of caucasian individuals whose haemophilia B carrier state can be diagnosed from 79% to 89%, demonstrate this widely applicable use of PCR for the detection of DNA polymorphism at cytosine phosphoguanadine dinucleotides irrespective of the methylation status.

Alleles↗
PubMed1987

Linkage relationships and allelic associations of the cystic fibrosis locus and four marker loci.

The linkage relationships between the cystic fibrosis (CF) locus and four marker loci (MET-H, MET-D, D7S8 and D7S16), allelic associations between these loci and the extent of informativity at these marker loci were investigated in a sample of 206 families with at least one child affected by CF. The data were contributed by 11 laboratories from Europe and Israel. The maximum lod scores and recombination frequency estimates (luminal diameter) (and confidence limits of luminal diameter) were: 18.3 at luminal diameter = 0.007 (0.001-0.038) for CF vs. MET, 11.0 at luminal diameter = 0.016 (0.001-0.068) for CF vs. D7S8, and 5.7 at luminal diameter = 0.0 (0.0-0.064) for CF vs. D7S16. A gene order of CF-MET-D7S8 was best supported by the data, but its preference to the order D7S8-CF-MET is mainly based on one single family. There are significant allelic associations between CF, MET, D7S8 and D7S16; these allelic associations affect the risk of random individuals to be carriers of CF.

Alleles↗
PubMed1987

Comparison of two dosage schedules of doxycycline in children with rickettsial spotted fever.

We carried out a randomized clinical trial with oral doxycycline in children with Israel rickettsial spotted fever. Our purpose was to investigate whether an abbreviated course of therapy with this drug (until the patient was afebrile plus one day) would be as effective as a one-week regimen of therapy. Results with 50 pediatric patients during this three-year study indicated that the abbreviated treatment regimen was as effective. This clinical trial may serve as a model for determining shorter durations of therapy for other diseases.

Child↗