PubMed Health⌕ Search

Biomedical subjects

R D Semba

Publications and source records attributed to R D Semba.

At least 73 records · Page 4Linked to original sources
PubMed1998

Serum vitamin A levels during tuberculosis and human immunodeficiency virus infection.

Vitamin A deficiency during tuberculosis and human immunodeficiency virus (HIV) infection has not been characterized. A cross-sectional study was conducted among HIV-infected adults with tuberculosis in Butare, Rwanda, in which 29% of the subjects had serum vitamin A levels consistent with deficiency (<1.05 micromol/L). Women had mean serum vitamin A levels of 1.22+/-0.45, compared with 1.47+/-0.68 in men (P < 0.07). A total of 37% of subjects with recent weight loss had vitamin A levels consistent with deficiency, compared with 14% of subjects without weight loss (P < 0.02). This study suggests that vitamin A deficiency is common among adults with tuberculosis and HIV infection in Rwanda.

Adult↗
PubMed1997

Ethics of HIV trials.

Explore the source record for details and available documents.

Africa South of the Sahara↗
PubMed1997

Maternal vitamin A deficiency and child growth failure during human immunodeficiency virus infection.

Although vitamin A is thought to influence growth, the relationship between maternal vitamin A deficiency during pregnancy and child growth is unknown. A longitudinal cohort study of 467 HIV-infected women and their children was conducted in Blantyre, Malawi. The children's weight and height were measured every 3 months until they were 24 months old. Maternal vitamin A deficiency was independently related to both linear and ponderal growth after adjustment for effects of body mass index, child gender, and child HIV status. By 12 months of age, infants born to mothers who were vitamin A-deficient during pregnancy weighed approximately 8% less (p < 0.001) and were approximately 2% shorter (p < 0.001) than infants born to mothers who were not deficient. This study suggests children born to HIV-infected women who are vitamin A-deficient during pregnancy are more likely to have growth failure.

Age Factors↗
PubMed1997

Syphilitic uveitis in human immunodeficiency virus-infected patients.

OBJECTIVE: To document the incidence and clinical features of syphilitic uveitis in patients coinfected with human immunodeficiency virus (HIV). DESIGN: Retrospective chart review. SETTINGS: Single tertiary uveitis referral center. PATIENTS: The charts of HIV-infected patients with uveitis and a reactive fluorescent treponemal antibody absorption test seen between November 1983 and June 1995 were reviewed. RESULTS: Syphilis was the most common bacterial cause of uveitis in this group. Thirteen patients (0.6% of the 2085 HIV-positive patients seen in the clinic during the study period) were dually infected. Twelve patients were male. Six patients (46%) had previously been treated for syphilis, 4 with intramuscular penicillin G benzathine only. Four patients (31%) had isolated anterior uveitis, 3 patients (23%) had anterior and intermediate uveitis, and 5 patients (38%) had panuveitis. One patient (8%) presented with optic nerve and retinal atrophy. Eight patients were treated with intravenous penicillin, 3 with intravenous and intramuscular penicillin, and 1 with intravenous ceftriaxone sodium. Of the 12 patients for whom follow-up examinations were available after treatment, ocular inflammation decreased in 11 (92%) and visual acuity improved in 8 (67%). Rapid plasma reagin titers decreased a median of 64-fold compared with pretreatment levels, and all patients with reactive cerebrospinal fluid who underwent pretreatment and posttreatment lumbar punctures normalized following therapy with intravenous antibiotics. CONCLUSIONS: Syphilis is an uncommon cause of uveitis in HIV-infected patients. Anterior uveitis is the most common ocular manifestation, but panuveitis is more common than isolated anterior uveitis. Intravenous penicillin is effective therapy.

Adult↗
PubMed1997

T cell subsets and cytomegalovirus retinitis in human immunodeficiency virus-infected patients.

A case-control study was done to investigate the relationship between T cell subsets and cytomegalovirus (CMV) retinitis in human immunodeficiency virus (HIV)-infected subjects with or without CMV retinitis and CD4+ cell counts of <0.050 x 10(9)/L. Cell surface markers on peripheral blood lymphocytes were evaluated using flow cytometry. Patients with CMV retinitis had significantly lower levels of CD8+ cells (median: 0.152 x 10(9)/L) compared with levels for controls (median: 0.296 x 10(9)/L, P < .001). Significant down-regulation of costimulatory molecule CD28+ and lymphocyte function-associated antigen-1 (LFA-1) expression was observed in patients versus controls (CD28+: 0.048 x 10(9)/L vs. 0.143 x 10(9)/L, P < .001; LFA-1: 0.238 x 10(9)/L vs. 0.400 x 10(9)/L, P < .001), but no significant differences were noted for NK cells. We propose that progressive loss of the CD3+ CD8+ cell subset and down-regulation of CD28 and LFA-1 accessory molecules are associated with an increased risk of CMV retinitis in HIV-infected patients.

AIDS-Related Opportunistic Infections↗
PubMed1997

Infant survival is improved by oral iodine supplementation.

Although reports suggest that infant mortality is increased during iodine deficiency, the effect of iodine supplementation on infant mortality is unknown. A double-masked, randomized, placebo-controlled, clinical trial of oral iodized oil was conducted in Subang, West Java, Indonesia to evaluate the effect of iodine supplementation on infant mortality. Infants were allocated to receive placebo or oral iodized oil (100 mg) at about 6 wk of age and were followed to 6 mo of age. Six hundred seventeen infants were enrolled in the study. Infant survival was apparently improved, as indicated by a 72% reduction in the risk of death during the first 2 mo of follow-up (P < 0.05) and a delay in the mean time to death among infants who died in the iodized oil group compared with infants who died in the placebo group (48 days vs. 17.5 d, P = 0.06). Other infant characteristics associated with reduced risk of death included weight-for-age at base line, consumption of solid foods, female gender and recent history of maternal iodine supplementation. Oral iodized oil supplementation had a stronger effect on the mortality of males compared with females. This study suggests that oral iodized oil supplementation of infants may reduce infant mortality in populations at risk for iodine deficiency.

Administration, Oral↗
PubMed1997

Vitamin A deficiency and maternal-infant transmissions of HIV in two metropolitan areas in the United States.

OBJECTIVE: To determine whether vitamin A deficiency is associated with maternal-infant HIV transmission among HIV-infected pregnant women in two United States cities. METHODS: Third trimester serum vitamin A levels were evaluated using high-performance liquid chromatography in 133 HIV-infected women who delivered livebirths during May 1986 to May 1994 and whose infants had known HIV infection status. RESULTS: Sixteen per cent (seven out of 44) of the transmitting mothers and 6% (five out of 89) of the non-transmitting mothers had severe vitamin A deficiency (< 0.70 mumol/l; P = 0.05). Maternal-infant transmission was also associated with prematurity < 37 weeks gestation (P = 0.02), and Cesarean section delivery (P = 0.04), CD4 percentage (P = 0.03) and marginally associated with duration of membrane rupture of > or = 4 h (P = 0.06) by univariate analysis. In a multivariate logistic regression model, severe vitamin A deficiency [adjusted odds ratio (AOR), 5.05; 95% confidence interval (CI), 1.20-21.24], Cesarean section delivery (AOR, 3.75; 95% CI, 1.10-12.87), and prematurity (AOR, 2.25; 95% CI, 1.22-4.13) were associated with transmission after adjusting for CD4+ percentage, and duration of membrane rupture. CONCLUSION: Increased risk of maternal-infant transmission was associated with severe vitamin A deficiency among non-breastfeeding women in these cohorts from the United States.

Adult↗
PubMed1997

Association between serum vitamin A and E levels and HIV-1 disease progression.

OBJECTIVE: To examine the associations between serum vitamin A and E levels and risk of progression to three key outcomes in HIV-1 infection: first AIDS diagnosis, CD4+ cell decline to < 200 cells x 10(6)/l, and mortality. DESIGN: Non-concurrent prospective study. METHODS: Serum levels of vitamins A and E were measured at the enrollment visit of 311 HIV-seroprevalent homo-/bisexual men participating in the Baltimore/ Washington DC site of the Multicenter AIDS Cohort Study. Cox proportional hazards models were used to estimate the relative hazard of progression to each outcome over the subsequent 9 years, adjusting for several independent covariates. RESULTS: Men in the highest quartile of serum vitamin E levels (> or = 23.5 mumol/l) showed a 34% decrease in risk of progression to AIDS compared with those in the lowest quartile [relative hazard (RH), 0.66; 95% confidence interval (CI), 0.41-1.06)]. This effect was statistically significant when comparing the highest quartile of serum vitamin E to the remainder of the cohort (RH, 0.67; 95% CI, 0.45-0.98). Associations between serum vitamin A levels and risk of progression to AIDS were less clear, but vitamin A levels were uniformly in the normal to high range (median = 2.44 mumol/l). Similar trends were observed for each vitamin with mortality as the outcome, but neither vitamin was associated with CD4+ cell decline to < 200 cells x 10(6)/l. Men who reported current use of multivitamin or single vitamin E supplements had significantly higher serum tocopherol levels than those who were not taking supplements (P = 0.0001). Serum retinol levels were unrelated to intake of multivitamin or single vitamin A supplements. CONCLUSIONS: These data suggest that high serum levels of vitamin E may be associated with slower HIV-1 disease progression, but no relationship was observed between retinol levels and disease progression in this vitamin A-replete population.

Acquired Immunodeficiency Syndrome↗
PubMed1997

Overview of the potential role of vitamin A in mother-to-child transmission of HIV-1.

Vitamin A is an essential micronutrient for normal immune function. Vitamin A deficiency is common among human immunodeficiency virus (HIV)-infected pregnant women and is associated with higher mother-to-child transmission of HIV-1 and increased infant mortality. The biological mechanisms by which vitamin A deficiency could influence mother-to-child transmission of HIV-1 include impairment of immune responses in both mother and infant, abnormal placental and vaginal pathology and increased HIV viral burden in breastmilk and blood. Clinical trials are currently in progress to determine whether daily micronutrient supplementation, including vitamin A, during pregnancy can reduce mother-to-child transmission of HIV-1.

Developing Countries↗
PubMed1997

Vitamin A levels and human immunodeficiency virus load in injection drug users.

Although low plasma vitamin A levels are associated with increased mortality and higher vertical transmission during human immunodeficiency virus (HIV) infection, it is unknown whether plasma low vitamin A levels are a marker for circulating HIV load. We conducted a cross-sectional study within a prospective cohort study of injection drug users in order to evaluate the relationship between plasma vitamin A levels and HIV viral load. Plasma vitamin A level was measured by high-performance liquid chromatography. Infectious viral load was measured by quantitative microculture of serial fivefold dilutions of 10(6) peripheral blood mononuclear cells. A total of 284 HIV-infected adults (79 women, 205 men) were studied. Plasma vitamin A levels consistent with deficiency were found in 28.9% of adults. A total of 38.0% of women and 25.3% of men had vitamin A deficiency (P < 0.04). The median infectious viral load for the entire study population was 8 infectious units per million cells. No significant relationship between plasma vitamin A levels and infectious viral load was observed in these injection drug users. This study suggests that there is no correlation between HIV viral load and plasma vitamin A levels in injection drug users, and these variables may represent independent risk factors during HIV infection. HIV-infected adult women appear to be at higher risk of developing vitamin A deficiency.

Adult↗
PubMed1997

Effect of vitamin A supplementation on measles vaccination in nine-month-old infants.

OBJECTIVE: Childhood immunization programs have been suggested as an infrastructure to deliver vitamin A supplements to children in developing countries. The effects of giving vitamin A, a potent immune enhancer, with measles immunization to nine-month-old infants is unknown. METHODS: A randomized, double-masked, placebo-controlled clinical trial of vitamin A, 100,000 IU at the time of standard titer Schwarz measles immunization was conducted with nine-month-old infants in Bogor District, West Java, Indonesia. Antibody titers to measles were measured at baseline and one and six months following immunization. RESULTS: 394 infants received measles immunization, and 37 infants (9.4%) had baseline antibody titers > 1:120, which is consistent with previous natural measles infection. Of the remaining infants, 98.8% seroconverted to measles, and 99.3% had titers consistent with protection against measles six months postimmunization. Seroconversion rates were similar in vitamin A and placebo treatment groups. CONCLUSION: High dose vitamin A supplementation can be given without reducing seroconversion to standard titer Schwatz measles immunization in nine-month-old infants.

Antibodies, Viral↗
PubMed1996

Vitamin A deficiency and T-cell subpopulations in children with meningococcal disease.

Although group A meningococcal disease is a major cause of child morbidity and mortality in sub-Saharan Africa, little is known about vitamin A status and T-cell subpopulations in affected children. A prospective study of vitamin A levels and T-cell subpopulations was conducted in 41 children hospitalized for meningococcal meningitis in Butare, Rwanda, during an epidemic from September through November, 1992. The mean age of cases was 3.6 +/- 2.7 years (range 0.5-16 years). The case-fatality rate was 20 per cent; 73 per cent of the children had serum vitamin A levels consistent with subclinical deficiency (< 0.7 mumol/l), and 27 per cent had levels consistent with severe deficiency (< 0.35 mumol/l). Mean CD4 per cent was higher and CD8 per cent was lower among children with meningitis compared with known reference populations. These results suggest that meningococcal disease is characterized by T-cell subpopulation alterations and vitamin A deficiency.

Adolescent↗
PubMed1996

Risk factors for xerophthalmia in the Republic of Kiribati.

OBJECTIVES: To identify risk factors for xerophthalmia in the Republic of Kiribati. DESIGN: Case-control study. SETTING: The Republic of Kiribati. SUBJECTS: 666 xerophthalmic preschool children (cases) and 816 children without xerophthalmia (controls) from a population-based sample of 4619 children who participated in a xerophthalmia prevalence survey. MAIN OUTCOME MEASURES: Clinical signs of xerophthalmia (night blindness, Bitot's spots, corneal xerophthalmia and keratomalacia). RESULTS: Multivariable logistic regression models showed older age [1.35(1.24, 1.47)] [odds ratio (95% confidence interval)]; male sex [1.32(1.05, 1.67)]; recent diarrhea [1.45(1.10, 1.89)]; severe [3.82(2.73, 5.35)], moderate [3.55(2.04, 6.18)], and mild [3.07(2.33, 4.04)] protein-energy malnutrition; current breast-feeding [0.30(0.19, 0.46)]; higher frequency of consumption of carotenoid-containing fruits and vegetables [0.93(0.80, 0.96)]; and the presence of a Foundation for the Peoples of the South Pacific garden project [0.70(0.52, 0.93)] were each independently associated with xerophthalmia. A recent history of measles was associated with corneal xerophthalmia [7.73(1.78, 33.65)]. CONCLUSIONS: These data provide further evidence of the relationship between xerophthalmia and factors that may be amenable to intervention, and suggest that greater availability and consumption of provitamin A carotenoids is associated with decreased risk of xerophthalmia among preschool children.

Breast Feeding↗
PubMed1995

Reduced seroconversion to measles in infants given vitamin A with measles vaccination.

Administration of 100,000 IU vitamin A at the time of measles immunisation is currently recommended for infants in developing countries. However, the safety and value of giving vitamin A, a potent immune enhancer, with live measles virus vaccines are unknown. We conducted a randomised, double-blind, placebo-controlled clinical trial in Indonesia to evaluate the effect of simultaneous vitamin A supplementation on the immune response to measles immunisation at six months of age. 336 infants received either vitamin A (100,000 IU) or placebo when immunised with standard-titre Schwarz measles vaccine. 82% of infants seroconverted to measles. In a multiple logistic regression model adjusting for maternal antibody titres, vitamin A supplementation was associated with a lower likelihood of seroconversion to measles (odds ratio 0.40, 95% CI 0.19-0.88), and girls were less likely to seroconvert than boys (0.34, 0.15-0.76). Immunisation with standard-titre Schwarz vaccine at six months of age in this study population is characterised by high seroconversion rates. However, simultaneous high-dose vitamin A may interfere with seroconversion to live measles vaccine in infants with maternal antibody.

Antibodies, Viral↗
PubMed1995

The decline of admissions for xerophthalmia at Cicendo Eye Hospital, Indonesia, 1981-1992.

Xerophthalmia due to vitamin A deficiency is a leading cause of blindness in children and has been a serious problem in Indonesia. To determine whether progress has been made in the eradication of xerophthalmia, we assessed hospital admissions for xerophthalmia at Cicendo Eye Hospital, Bandung, Indonesia. The hospital admission registry from 1981 to 1992 was reviewed. Between January 1981 and December 1992, there were 117 admissions for xerophthalmia, and of these, 63 were boys and 54 were girls, with an average age of 3.9 +/- 0.3 years. Hospital admissions for xerophthalmia declined steeply from 1981 to 1985, with a few rare cases from 1985 through 1992. During the same period from 1981 through 1992, there were no overall changes in total hospital admissions or total pediatric admissions. These results suggest that xerophthalmia is becoming less common in Indonesia.

Age Distribution↗
PubMed1995

Vitamin A deficiency in the South Pacific.

UNLABELLED: Vitamin A deficiency is a major cause of morbidity, mortality and blindness among children. Although vitamin A deficiency is known to affect many children in developing countries, the magnitude of the problem in the South Pacific region is unclear. METHODS: Five cross-sectional surveys for vitamin A deficiency were conducted between 1989 and 1992 in the Republic of Kiribati, Tuvalu, the Republic of Vanuatu, Solomon Islands and the Cook Islands. RESULTS: In total, 10,673 children between the ages of 6 and 72 months were examined for clinical signs of vitamin A deficiency (nightblindness and xerophthalmia). The prevalence of xerophthalmia was 14.76% in the Republic of Kiribati, 1.55% in Solomon Islands, 0.59% in the Cook Islands, 0.28% in Tuvalu, and 0.11% in Vanuatu. The most common clinical findings were Bitot's spots followed by nightblindness. Xerophthalmia were more common among boys (Kiribati P < 0.001, Solomon Islands P = 0.03) and tended to occur in older preschool children (P < 0.0001). CONCLUSIONS: These studies suggest that vitamin A deficiency is a public health problem in the Republic of Kiribati and Solomon Islands.

Child↗