Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0024530 (malaria)
 44,886 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

It has been claimed that vitamin A deficiency increases the severity of malarial infection in rats. We measured parasitemia, mortality, serum retinol, liver retinol, spleen weight, and degree of xerophthalmia in vitamin A-deficient rats (A-), pair-fed control rats (A+PF), and ad libitum-fed control rats (A+AL) infected with Plasmodium berghei, a rodent malarial parasite. In experiments 1 and 2 vitamin A deprivation began at weaning. Parasitemia and mortality among mildly deficient (expt. 1, mean serum retinol 19 micrograms/dl) or acutely deficient rats (expt. 2, mean serum retinol less than 5 micrograms/dl) infected with P. berghei were not significantly different from those of infected A+AL or A+PF rats. Furthermore, when the mildly deficient rats were given a second, larger dose of P. berghei, all demonstrated complete immunity to the parasite. However, when vitamin A was withdrawn midway through pregnancy (expt. 3), the A- rats experienced significantly higher parasitemia and mortality during infection with P. berghei. Malaria caused a significant decrease in the serum retinol but not liver retinol of the A+PF and A+AL rats. Among the acutely deficient rats, xerophthalmia was significantly more prevalent and more severe among those infected with malaria than among those not infected with malaria. Malaria and vitamin A deficiency acted synergistically to increase spleen weight, and this interaction was highly significant. In these experiments, vitamin A deficiency decreased the rats' ability to recover from malaria, but only when the deficiency began early in life, was very severe, and the rats were young when infected.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Interactions between vitamin A deficiency and Plasmodium berghei infection in the rat. 269 6

Surveillance of drug consumption and disease incidence from medical relief missions in two locations--southeast Asia and eastern Africa--revealed close similarities. Analgesics, antibiotics, antimalarials, antihistamine or decongestant preparations (or both), bronchodilators, and scabicides were the 10 most commonly used drugs. Orthopedic, respiratory, gastrointestinal, dermatologic, and ophthalmic conditions, malaria, sexually transmitted diseases, and parasitic infestations were encountered most frequently. Recognition and early treatment of xerophthalmia, trachoma, and onchocerciasis, which are rare in more developed countries but common at tropical latitudes, can prevent the blindness that results from untreated disease progression. Pulse-temperature relationships and fever patterns may offer diagnostic clues to physicians deprived of laboratory support. Important logistic considerations, disease incidences, and selected topics and idiosyncrasies of humanitarian aid missions to tropical communities are discussed in hopes of aiding providers who are planning future relief missions.
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PMID:Planning a medical relief mission. 786 Mar 67

Although most studies on the effect of vitamin A supplementation have reported reductions in childhood mortality, the effects on morbidity are less clear. We have carried out two double-blind, randomised, placebo-controlled trials of vitamin A supplementation in adjacent populations in northern Ghana to assess the impact on childhood morbidity and mortality. The Survival Study included 21,906 children aged 6-90 months in 185 geographical clusters, who were followed for up to 26 months. The Health Study included 1455 children aged 6-59 months, who were monitored weekly for a year. Children were randomly assigned either 200,000 IU retinol equivalent (100,000 IU under 12 months) or placebo every 4 months; randomisation was by individual in the Health Study and by cluster in the Survival Study. There were no significant differences in the Health Study between the vitamin A and placebo groups in the prevalence of diarrhoea or acute respiratory infections; of the symptoms and conditions specifically asked about, only vomiting and anorexia were significantly less frequent in the supplemented children. Vitamin-A-supplemented children had significantly fewer attendances at clinics (rate ratio 0.88 [95% CI 0.81-0.95], p = 0.001), hospital admissions (0.62 [0.42-0.93], p = 0.02), and deaths (0.81 [0.68-0.98], p = 0.03) than children who received placebo. The extent of the effect on morbidity and mortality did not vary significantly with age or sex. However, the mortality rate due to acute gastroenteritis was lower in vitamin-A-supplemented than in placebo clusters (0.66 [0.47-0.92], p = 0.02); mortality rates for all other causes except acute lower respiratory infections and malaria were also lower in vitamin A clusters, but not significantly so. Improving the vitamin A intake of young children in populations where xerophthalmia exists, even at relatively low prevalence, should be a high priority for health and agricultural services in Africa and elsewhere.
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PMID:Vitamin A supplementation in northern Ghana: effects on clinic attendances, hospital admissions, and child mortality. Ghana VAST Study Team. 810 78

Onchocerciasis is commonly known as River Blindness and affects about 18 million people around the world. It is transmitted by black flies that breed in river and stream rapids and transmit the parasitic microfilariae, Onchocerca volvulus, to people who live and work near such rivers. Infection with the microfilariae results in blindness or visual impairment for 1 or 2 million people. The microfilariae migrate to superficial tissues and may invade any part of the eye and ocular structure. Living worms cause little damage, however, their death triggers a localized inflammation which can lead to blindness. Sclerosing keratitis, a severe corneal involvement, is the major cause of blindness from the disease. The World Health Organization (WHO) Expert Committee on Onchocerciasis has estimated that 9% of the disease is found in Africa, the rest occur in Yemen and Latin America. Treatment with ivermectin is contraindicated for pregnant and lactating women, children under 5 years of age, asthmatics, and people with other diseases. The WHO Onchocerciasis Control Program in 11 countries of West Africa has eliminated the risk of onchocerciasis by aerial spraying of black fly breeding sites only from 1 country. A single annual oral dose (150 mg/kg) of ivermectin can reverse early lesions in the cornea. Ivermectin must be taken annually to sustain protection against blindness, thus its incorporation into primary health care along with malaria, AIDS, trachoma, xerophthalmia, and cataract is most cost effective. Nigeria and Tanzania have optometry schools, and optometrists can play a significant role in onchocerciasis control and blindness prevention programs by training local health care workers to distribute invermectin in vision screening programs.
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PMID:Onchocerciasis and other eye problems in developing countries: a challenge for optometrists. 824 90

A total of 14,740 schoolchildren in seven provinces of Shoa Administrative Region in Central Ethiopia were surveyed for the prevalence of goitre, xerophthalmia and anaemia. Haemoglobin and packed cell volume were assessed in 966 children in one province while an in-depth study was conducted on 344 children in the same province and two others. Goitre, xerophthalmia (Bitot's spots) and clinical anaemia were observed in 34.2, 0.91 and 18.6% respectively of the children. Most biochemical variables were within the normal range while those of haemoglobin (Hb), mean corpuscular Hb concentration (MCHC) and urinary I excretion were lower, and mean corpuscular volume, mean corpuscular Hb (MCH), and immunoglobulins G and M were higher. Hb was strongly correlated with retinol, ferritin, MCHC, MCH, packed cell volume and erythrocyte count while retinol formed a triad with transthyretin (TTR) and retinol-binding protein (RBP) which were all correlated with one another. Total and free thyroxin and total and free triiodothyronine were positively correlated as were the concentrations of the total and free hormones. Thyrotropin (TSH) was negatively correlated with total and free thyroxin and positively correlated with free triiodothyronine. Thyroxin and triiodothyronine in both free and combined forms were all correlated with thyroxin-binding globulin which in turn was negatively correlated with the triad retinol, RBP and TTR. The triad was also negatively correlated with C-reactive protein. Urinary I excretion was positively associated with total thyroxin and negatively associated with TSH. The anaemia found was not nutritional in origin but due to the effect of infestation with intestinal parasites and malaria.
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PMID:Interrelationship between vitamin A, iodine and iron status in schoolchildren in Shoa Region, central Ethiopia. 826 Apr 84

Research is one of the four main activities of AITO. It is vital for the determination of health care priorities, and for the design, implementation, and evaluation of programs and projects in OCCCMED countries. Most of the research is surgical and focused on the diseases which cause blindness. Cataracts are the principal cause of blindness and have been the focus of many studies aimed at making surgery more accessible in terms of both geographical availability and cost. Trachoma is a major public health priority in the countries of the Sahel and a survey of its prevalence is underway in several countries. This study should lead to the development of preventive and curative treatments aimed at controlling blindness caused by trachoma by the year, 2020. Vitamin A deficiency, the cause of xerophthalmia and high mortality rates in infants, has been surveyed in several countries. A survey of glaucoma, another major cause of blindness which is often not recognized or treated, will be carried out in Bamako. Other studies focus on leprosy, malaria and the effects of visual disability on the quality of everyday life. It will be a major challenge over the next five years to develop the capacity within local populations to identify, design and implement research programs in community health aspects of ophthalmology that will take into account the needs and constraints of sub-Saharan Africa.
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PMID:[Research at the African Institute of Tropical Ophthalmology]. 964 37

Vitamin A status in a sample of pregnant and lactating women living in several representative regions of Congo was assessed and compared between August and September 2004. This survey was conducted using a randomized two-stage cluster-sampling method with stratification on 90 clusters, each consisting of at least 15 women. Vitamin A status was determined in a total of 1,054 individuals, using the impression cytology with transfer (ICT) test, the modified relative dose response test (MRDR test) on dried blood spots (DBS), and clinical examination to detect signs of xerophthalmia. The clinical criterion defining vitamin A deficiency was the presence of active xerophthalmia (Bitot's spots [X1B]), active corneal disease), and/or night blindness (XN stage). The prevalence of clinical signs of stage XN and X1B xerophthalmia in the Republic of Congo was found to be 16% and 19% respectively. The prevalence of clinical signs (X1B) was greater in the rural north than in urban areas, with a gradient running from urban (5%) to rural area (33%); 27% of all the ICT tests showed that the subjects were suffering from vitamin A deficiency. The deficiency rates were significantly higher (p < 0.001) in urban surroundings (Brazzaville) than in the rural northern regions. The biochemical MRDR test showed the presence of vitamin A deficiency (> or = 0.06) in 26% of the mothers in Brazzaville compared to 6% in the town of Kouilou; 44% of the women had retinol levels of < 10 microg/dL in the rural north whereas these percentages were significantly lower in the urban areas surveyed (chi-square = 62.30, p < 0.001). A significant correlation was found to exist (p < 0.001) between the ICT test and the MRDR test on DBS. In the population as a whole, 30% of the mothers suffering from malarial attack had abnormally low MRDR levels (> or = 0.06) compared to no malaria. The results of the present study confirm that vitamin A deficiency is a serious public-health issue in pregnant and lactating mothers in the Republic of Congo.
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PMID:Prevalence of vitamin A deficiency in pregnant and lactating women in the Republic of Congo. 2361 2