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S Moses

Publications and source records attributed to S Moses.

At least 37 records · Page 2Linked to original sources
PubMed1996

Prenatal diagnosis of glycogen storage disease type 1a by single stranded conformation polymorphism (SSCP).

Glycogen storage disease type 1a (GSD 1a), a severe metabolic disorder, is caused by the absence of glucose-6-phosphatase (G6Pase) activity. Diagnosis is currently established by demonstrating the lack of G6Pase activity in the patient's liver specimen. Enzymatic diagnosis cannot be performed in chorionic villi or amniocytes as G6Pase is active only in the liver, kidney, and intestinal mucosa. Recent cloning of the G6Pase gene and subsequent identification of the mutations causing GSD 1a have led to the possibility of performing DNA-based diagnosis in chorionic villus samples (CVS) or amniocytes. Here we report the first DNA-based prenatal diagnosis in two families in whom GSD 1a patients were diagnosed. In one Jewish family with a previously identified R83C mutation, single-stranded conformation polymorphism (SSCP) analysis of the DNA extracted from CVS showed a homozygous R83C mutant pattern. As a result, the pregnancy was terminated and the diagnosis was confirmed on DNA analysis of the aborted fetus. In another family of Arabic extraction in which a V166G mutation has been identified in one of the siblings, SSCP analysis performed on DNA extracted from CVS presented the pattern of a normal control. The pregnancy was carried to term and a healthy baby was born. Thus, once mutations causing the disease are identified, prenatal diagnosis of GSD 1a is possible. SSCP analysis of DNA prepared from CVS is reliable, simple and fast, making it a suitable method for prenatal diagnosis.

Chorionic Villi Sampling↗
PubMed1996

Ataxia with isolated vitamin E deficiency in four siblings.

We describe 4 siblings of a consanguineous Bedouin family with Friedreich ataxia phenotype in whom low serum vitamin E levels without other indicators of fat malabsorption were detected. Although age of onset and some of the clinical features were alike in all 4 patients, the electrophysiological parameters were markedly abnormal in 2, but normal in the other 2. Erythrocytes revealed both membranous and intracellular evidence of oxidative damage. The mutations described in other families with ataxia with isolated vitamin E deficiency were not detectable, nor was an abnormal single-stranded conformation polymorphism pattern apparent in the three exons at the 3' region of the gene. Vitamin E administration in pharmacological doses improved the neurological condition in 2 patients and also corrected some of the patients' erythrocyte cell abnormalities. The finding of vitamin E deficiency in other cases of Friedreich ataxia phenotype may allow treatment at an early stage of the disease, when large dose Vitamin E therapy may reverse the neurological lesions.

Adult↗
PubMed1996

Increased risk of infection with human immunodeficiency virus type 1 among uncircumcised men presenting with genital ulcer disease in Kenya.

The factors responsible for the explosive spread of human immunodeficiency virus type 1 (HIV-1) in sub-Saharan Africa continue to be identified and debated. One of the most controversial factors has been male circumcision. This cross-sectional study was conducted to measure the association between circumcision status and infection with HIV-1 among men with genital ulcer disease. Eight hundred and ten men participated in the study, of whom 190 (23%) were HIV-1-positive. A logistic regression model adjusted for behavioral and historical showed that HIV-1 positivity was independently associated with being uncircumcised (adjusted odds ratio [OR], 4.8; 95% confidence interval [CI], 3.3-7.2) and with a history of urethral discharge (adjusted OR, 2.0; 95% CI, 1.4-2.8). This association could not be explained by measures of sexual exposure to HIV-1 among this population. Male circumcision should be considered as an intervention strategy for AIDS control.

Adolescent↗
PubMed1996

Focused peer-mediated educational programs among female sex workers to reduce sexually transmitted disease and human immunodeficiency virus transmission in Kenya and Zimbabwe.

Peer-mediated education programs in Kenya and Zimbabwe focusing on female sex workers for the control of human immunodeficiency virus (HIV) infection and other sexually transmitted diseases (STDs) have led to increased condom use and increased adoption of other safer sex practices, as well as declines in STD and HIV incidence among female sex workers. It is likely that similar declines have occurred among their clients and possibly in the general community, although supporting data are limited. These results are encouraging. However, progress in increasing the scale and coverage of intervention programs among female sex workers has been slow. Constraints to expanding program coverage include inadequate political commitment; deficiencies in program planning, management, and human resources; and insufficient funding. The challenges currently are to show that behavioral change can be sustained and to scale up activities from small demonstration projects to district, provincial, and national levels.

Catchment Area, Health↗
PubMed1996

Identifying cervical infection among pregnant women in Nairobi, Kenya: limitations of risk assessment and symptom-based approaches.

OBJECTIVES: To examine characteristics of pregnant women associated with cervical infection, and to evaluate the accuracy of symptom-based and risk assessment systems which have been developed for identifying cervical infection in antenatal women. METHODS: Interviews were conducted and physical examinations performed on 291 consecutive antenatal clinic attenders in nairobi, Kenya. Vaginal, cervical, urine and blood specimens were also obtained for analysis. RESULTS: The following disease prevalences were observed: candidiasis 26.2%; trichomoniasis 19.9%; bacterial vaginosis 20.6%; any vaginal infection 53.8%; chlamydial cervicitis (CT) 8.8%; gonococcal cervicitis (GC) 2.4%; any cervical infection 10.8%. The only statistically significant association with GC and/or CT cervical infection was the presence of cervical friability (OR = 2.1, P = 0.05). There were trends towards associations with the presence of endocervical mucopus (OR = 2.6, P = 0.06), reporting a new sex partner in the past 3 months (OR = 2.2, P = 0.16) and reporting that a sex partner had an STD-related symptom (OR = 4.4, P = 0.13). There were no associations with other demographic, behavioural or medical characteristics. Risk scores previously developed for detecting GC/CT cervicitis in developing country antenatal populations generally performed poorly. CONCLUSIONS: The prevalences of vaginal and cervical infection observed were extremely high among these "low risk" women. Owing probably to high levels of vaginal infection and to behavioural characteristics of this urban population, factors which elsewhere have been associated with cervical infection were not found to be so in this setting. Further work on symptom-based approaches and risk assessment for STD case detection in pregnant women is required before STD management recommendations can be generalised.

Adult↗
PubMed1996

Genital ulcer disease among STD clinic attenders in Nairobi: association with HIV-1 and circumcision status.

In previous studies, genital ulcers in men have been found to be associated with increased risk of HIV-1 seroconversion. To further explore this association male patients attending a sexually transmitted disease (STD) clinic in Nairobi for either urethritis (controls, n = 276) or a genital ulcer (cases, n = 607) were compared with respect to sexual behaviour, presence of HIV-1 antibody and circumcision status. Patients were followed to study risk factors for incident genital ulcers and HIV-1 seroconversion. At entry, being married was associated with higher prevalence of HIV-1 (OR = 1.76) and genital ulcers (OR = 1.42). Lack of circumcision was associated with both HIV-1 infection (OR = 4.67) and the presence of a genital ulcer (OR = 2.23). Genital ulcers were also associated with HIV-1 infection (OR = 1.87) independent of circumcision status. On follow-up, HIV-1 seropositivity was associated with incident genital ulcers. It is argued that the association between genital ulcers and HIV-1 infection may be more complex than ulcers simply being a risk factor for HIV-1 infection, and that HIV-1 infection may either increase the risk of acquiring a genital ulcer, or HIV-1 infection and genital ulcers may have some unknown risk factor in common.

Adult↗
PubMed1995

Comparison of the declines in CD4 counts in HIV-1-seropositive female sex workers and women from the general population in Nairobi, Kenya.

Studies from Kenya have reported rapid clinical disease progression among HIV-infected professional sex workers. The reasons for this rapid decline are unknown. To better understand factors influencing the course of disease, HIV-1 disease progression was explored in terms of declines in CD4 counts. Two samples from Nairobi, Kenya, were studied, one from a cohort of female sex workers and another, as a comparison group, from mothers enrolled in an HIV-1 vertical-transmission study. A Markov model was used to analyze transitions between HIV-1 disease stages as defined by CD4 counts. It appears that sex workers experience a rapid decline in CD4 counts, consistent with earlier findings of rapid clinical disease progression among individuals in this group. The rate of decline in CD4 counts among the mothers appears to be lower. It is speculated that either intensive exposure to sexually transmitted pathogens or infection with several strains of HIV-1 may account for the rapid disease progression among female sex workers.

Adult↗
PubMed1995

Logistic regression in case-control studies: the effect of using independent as dependent variables.

In case-control studies, cases are sampled separately from controls. In such studies the primary analysis concerns the estimation of the effect of covariables on being a case or a control. To explore causal pathways, further secondary analysis could concern the relationships among the covariables. In this paper the validity of such secondary analysis is addressed. In particular, the use of multiple logistic regression in case-control studies where the dependent variable is not the case/control indicator is explored. It is shown that only under very restrictive conditions will sample regression coefficients correctly estimate their true value. In many situations, it may be valid to regress one covariable on others in the control group, but not in the case group or the combined sample. This principle is illustrated by a study of sexually transmitted disease in Kenya.

Case-Control Studies↗
PubMed1995

The duration of breastfeeding by HIV-1-infected mothers in developing countries: balancing benefits and risks.

How best to advise mothers infected with human immunodeficiency virus type 1 (HIV-1) in developing countries regarding breastfeeding is an important issue that has generated considerable debate. Previous studies have addressed this problem by means of mathematical models, but without considering the issue of the duration of breastfeeding. A mathematical model was developed to compare the age-specific risks of mother-to-child HIV transmission versus the excess mortality due to not breastfeeding. In this model it is assumed that both the risk of mother-to-child transmission of HIV through breast milk and the relative risk of not breastfeeding do not vary with age. The model indicates that, in HIV-1-seropositive mothers, the decrease in child mortality afforded by breastfeeding may exceed the risk of mother-to-child HIV-1 transmission only during the first 3-7 months of life. Thereafter the risk of HIV-1 transmission probably exceeds the mortality benefit of breastfeeding. Experimental studies of counselling HIV-1-infected mothers to limit their duration of breastfeeding should be considered in the setting of developing countries.

Breast Feeding↗
PubMed1995

Characterization of the mutations in the glucose-6-phosphatase gene in Israeli patients with glycogen storage disease type 1a: R83C in six Jews and a novel V166G mutation in a Muslim Arab.

Glycogen storage disease type 1a (GSD 1a), an autosomal recessive disease, is caused by the inactivity of glucose-6-phosphatase, the gene of which has been recently cloned. We report on the missense mutation C-->T at nucleotide 326 of the G6Pase gene, causing the change of the Arg codon at position 83 into a Cys codon, as the single mutation detected in six Jewish patients. This finding suggests that this mutation might be prevalent among the Jewish population. A new missense mutation T-->G at nucleotide 576 resulting in V166G was found in an Arab Muslim patient. These families may benefit now from pre- and postnatal diagnosis by analysis of DNA from blood and amniotic fluid or chorionic villus cells rather than liver biopsy. No mutations in the G6Pase gene were detected in two GSD 1b patients.

Arab World↗
PubMed1995

Syphilis control in pregnancy: decentralization of screening facilities to primary care level, a demonstration project in Nairobi, Kenya.

A decentralized syphilis control program in pregnant women was implemented in nine Nairobi City Council antenatal clinics between July 1992 and August 1993, whereby pregnant women were screened for syphilis, treated before leaving the clinic if RPR seroreactive, and counselled on the importance of partner treatment and sexual abstinence during treatment in order to protect their unborn babies from getting congenital syphilis. A total of 13,131 pregnant women were screened for syphilis (RPR test), 87.3% of seroreactive women were treated on site and 50% of partners returned to the clinic and were treated. The prevalence of RPR reactivity was 6.5%. Based on other data the program could theoretically have prevented 413 cases of congenital syphilis at a cost of approximately 50 USD per prevented case. This demonstration project shows that decentralized prevention of congenital syphilis in antenatal clinics by nurses is feasible and inexpensive and should receive priority in resource allocation in reproductive health and child survival programs.

Female↗
PubMed1995

Rapid progression to disease in African sex workers with human immunodeficiency virus type 1 infection.

From a cohort of female sex workers in Nairobi, Kenya, 163 women were observed to seroconvert to human immunodeficiency virus type 1 (HIV-1) and followed to study progression to HIV-1-related disease. The effect of several covariables on disease progression was studied using a Weibull proportional hazards model. The Weibull survival model was fitted to the observed incubation times. Estimates of the median duration to CDC stage IV-A and IV-C disease were 3.5 and 4.4 years, respectively. Condom use before seroconversion was associated with a reduced risk of CDC stage IV-A disease (relative risk = .64, P < .05). The incubation time of HIV-1-related disease is extremely short in this population.

Acquired Immunodeficiency Syndrome↗
PubMed1995

Human immunodeficiency virus type 1-infected cells in breast milk: association with immunosuppression and vitamin A deficiency.

Breast milk samples from human immunodeficiency virus type 1 (HIV-1)-seropositive women were analyzed by polymerase chain reaction to determine the prevalence and determinants of HIV-1-infected cells in breast milk. Breast milk samples (212) were collected from 107 women, and 58% of the samples had detectable HIV-1 DNA. The proportion of HIV-1-infected cells in the milk samples ranged from 1 to 3255/10(4) cells. Breast milk samples with detectable HIV-1 DNA were more likely to be from women with absolute CD4 cell counts of < 400 (odds ratio, 3.1; 95% confidence interval [CI], 1.5-7.0). Severe vitamin A deficiency (< 20 micrograms/dL) was associated with a 20-fold increased risk of having HIV-1 DNA in breast milk among women with < 400 CD4 cells/mm3 (95% CI, 2.1-188.5). Women with CD4 cell depletion, especially those with vitamin A deficiency, may be at increased risk of transmitting HIV-1 to their infants through breast milk.

Adolescent↗