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)

Malnutrition interacting with infectious and parasitic diseases are the main causes of the appalling mortality in childhood in the tropics. The most important single safeguard against these in infancy is breast feeding and the trend now evident to abandon this is a disaster which demands urgent attention. Reasons for this trend are discussed. Efforts to control infectious diseases, other than smallpox, have had little success and the emergence and spread of dengue haemorrhagic fever in S.E. Asia have added new dimensions to the problem. Malaria is still widely prevalent in the tropics and falciparum malaria, holoendemic in much of Africa, remains a major cause of death with its most serious impact on pregnant women and children. The emergence and spread of drug resistant strains of this parasite in parts of the world is a cause for serious concern. Quartan malaria is also an insidious corruptor of health in childhood and commonly causes the nephrotic syndrome. Neonatal jaundice, often associated with G6PD deficiency, is increasing in frequency in urban areas of Africa and now constitutes a significant hazard to the newborn and requires urgent investigation. These problems in tropical paediatrics indicate the need for urgent reappraisal of our role as a profession in the affairs of the tropical developing world.
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PMID:Aspects of tropical paediatrics. 79 3

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common human enzymopathy. Because its gene locus is on the X-chromosome it is more common in males than females in all populations. Prevalence rates vary from 62% among Kurdish Jews to the very low rates (0.1% or less in Japan, for example), which are compatible with sporadic cases arising from spontaneous mutations. However, there is at least one population in which G6PD deficiency has not been found, namely the indigenous (Amerindian) population of America. Approximately 400 variants have been described. Despite the clinical burden imposed by this enzymopathy, polymorphic frequencies have been reached in many populations. There is abundant epidemiological evidence that this has happened because of a biological advantage conferred on heterozygotes in falciparum malaria endemic areas. This advantage may apply to quartan malaria as well. Clinical severity varies, from the rare chronic nonspherocytic haemolytic anaemia to progressively milder forms like the Mediterranean and A- types. The other clinical syndromes, i.e. neonatal jaundice and haemolysis caused by infections, foods, drugs and chemicals, are not always predictable. This is because only a fraction of such enzymopathic persons develop these syndromes after exposure to the relevant stimulus. Modern techniques of molecular biology may elucidate why this is so. There is some emerging evidence that the genetic burden or survival value associated with G6PD deficiency may be relevant not only in tropical and infectious diseases, but also in their chemotherapy (e.g. malaria) as well as in the control of a long-recognized environmental pollutant such as lead.
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PMID:Glucose-6-phosphate dehydrogenase deficiency. 151 Nov 80

Mortality of infants aged 0-30 months was studied in a subdistrict of the eastern Ivory Coast with a population of 240,000 inhabitants. A cluster sample of the type recommended by the World Health Organization for evaluating progress of the expanded program of immunizations consisted of 2 samples with 30 clusters of 70 children each, 1 taken in urban Abengourou and the other in rural cantons of the subprefecture of Abengourou. A standardized questionnaire was administered to all the mothers about their births within the last 3 years. Supplementary questionnaires concerning all deaths of children of the sample mothers were interpreted by 3 physicians who agreed on a probably diagnosis in each case. The survey covered 2375 infants under 1 year and 1825 aged 12-30 months. The total mortality was 103 deaths in the total sample and 70 for infants aged 0-11 months, for a rate of 29.4%. The difference between the urban rate (31.7%) and the rural rate (26.8%) was not significant. The rate varied significantly by sex for deaths due to malnutrition (11 boys, 1 girl), and pneumopathies (6 girls, 1 boy). Mortality varied significantly according to treatment received and place of death. 55% received traditional treatment and 45% modern treatment. 53% died at home, 36% at a health center, and 9% at the home of a healer. Among infants aged 0-27 days, the cause of death was tetanus for 8, prematurity for 12, neonatal distress for 5, neonatal jaundice for 5, and infection for 2. Among infants aged 1-11 months the cause of death was malaria for 10, meningitis for 7, tetanus for 2, diarrhea for 9, pneumopathy for 3, measles for 4, whooping cough for 2, and unknown for 1. Among infants aged 12-30 months the cause of death was malaria for 11, malnutrition for 12, meningitis for 3, pneumopathy for 4, measles for 1, and sickle cell anemia for 2. Malaria was the single most important cause of death followed by malnutrition for the overall sample. In urban and rural areas respectively, the proportions of infants correctly vaccinated for their age groups were 78.1% and 76.0% for those under 11 months; 92.3% and 80.6% for those 12-17 months; 78.3% and 76.6% for those 18-23 months; and 66.5% and 71.4% for those 24 months and over. Mortality rates varied very significantly by vaccination status. 70 of the children dying had not been vaccinated. Their mortality rate was 19.6%, compared to .5% for children in process of vaccination, 1.1% for children incompletely vaccinated, and .9% for children correctly vaccinated.
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PMID:[Infant mortality and its causes in a sub-district of the Ivory Coast]. 196 15

In studying the relationship between genetic abnormalities of red blood cells and malaria endemicity in the Vanuatu archipelago in the southwestern Pacific, we have found that of 1,442 males tested, 98 (6.8%) were G6PD deficient. The prevalence of GdPD deficiency varied widely (0%-39%), both from one island to another and in different parts of the same island, and generally correlated positively with the degree of malaria transmission. The properties of G6PD from GdPD-deficient subjects were analyzed in a subset of 53 samples. In all cases the residual red-blood-cell activity was < 10%. There were three phenotypic patterns. PCR amplification and sequencing of the entire coding region of the G6PD gene showed that the first of these patterns corresponded to G6PD Union (nucleotide 1360C-->T; amino acid 454Arg-->Cys), previously encountered elsewhere. Analysis of samples exhibiting the second pattern revealed two new mutants: G6PD Vanua Lava (nucleotide 383T-->C; amino acid 128Leu-->Pro) and G6PD Namoru (nucleotide 208T-->C; amino acid 70Tyr-->His); in three samples, the underlying mutation has not yet been identified. Analysis of the sample exhibiting the third pattern revealed another new mutant: G6PD Naone (nucleotide 497G-->A; amino acid 166Arg-->His). Of the four mutations, G6PD Union and G6PD Vanua Lava have a polymorphic frequency in more than one island; and G6PD Vanua Lava has also been detected in a sample from Papua New Guinea. G6PD deficiency is of clinical importance in Vanuatu because it is a cause of neonatal jaundice and is responsible for numerous episodes of drug-induced acute hemolytic anemia.
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PMID:Multiple glucose 6-phosphate dehydrogenase-deficient variants correlate with malaria endemicity in the Vanuatu archipelago (southwestern Pacific). 782 90

The glucose-6-phosphate dehydrogenase (G6PD) gene is X-linked. There are numerous mutations that cause a deficiency of this enzyme in erythrocytes. G6PD deficiency can produce anemia, both when drugs are administered and under the stress induced by infection. Functionally severe variants cause hereditary non-spherocytic hemolytic anemia, i.e. anemia even in the absence of stress. Neonatal jaundice occurs in G6PD deficiency, but it is likely that it is largely due to impairment of liver function, rather than to hemolysis. It has been suggested that there are clinical manifestations of G6PD deficiency that are related to other tissues, but the existence of these is not well documented. Some mutations that produce G6PD deficiency in red cells exist at polymorphic frequencies. Individuals with such mutations seem to have enjoyed a selective advantage because of resistance to falciparum malaria. Different mutations, each characteristic of certain populations, are found, and have been characterized at the deoxyribonucleic acid (DNA) level. G6PD A-(202A376G) is the most common African mutation. G6PD Mediterranean(563T) is found in Southern Europe, the Middle East and in the Indian subcontinent. Several other mutations are common in Asia. Genetic variability of G6PD has played an important role in the understanding of a variety of developmental processes.
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PMID:G6PD: population genetics and clinical manifestations. 886 Dec 78

Glucose-6-phosphate dehydrogenase (G6PD) is expressed in all tissues, where it catalyses the first step in the pentose phosphate pathway. G6PD deficiency is prevalent throughout tropical and subtropical regions of the world because of the protection it affords during malaria infection. Although most affected individuals are asymptomatic, there is a risk of neonatal jaundice and acute haemolytic anaemia, triggered by infection and the ingestion of certain drugs and broad beans (favism). A rare but more severe form of G6PD deficiency is found throughout the world and is associated with chronic non-spherocytic haemolytic anaemia. Many deficient variants of G6PD have been described. DNA sequence analysis has shown that the vast majority of these are caused by single amino acid substitutions. The three-dimensional structure of G6PD shows a classical dinucleotide binding domain and a novel beta + alpha domain involved in dimerization.
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PMID:Glucose-6-phosphate dehydrogenase deficiency. 1091 76

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the commonest red cell enzymopathy in humans and has an X-linked inheritance. It has been reported from India more than 30 years ago and the prevalence varies from 0-27% in different caste, ethnic and linguistic groups. The major clinical manifestations are drug induced hemolytic anemia, neonatal jaundice and chronic non-spherocytic hemolytic anemia. Individuals with G6PD deficiency have a selective advantage against falciparum malaria. Thirteen biochemically characterized variants have been reported from India. At the molecular level, G6PD Mediterranean is the most common deficient variant in the caste groups whereas, G6PD Orissa is more prevalent among the tribal of India. The third common variant seen in India is G6PD Kerala-Kalyan.
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PMID:Glucose-6-phosphate dehydrogenase deficiency in India. 1522 63

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is common in malaria endemic regions and is estimated to affect more than 400 million people worldwide. Deficient subjects are mostly asymptomatic but clinical manifestations range from neonatal jaundice due to acute hemolytic anemia to chronic non-spherocytic hemolytic anemia. To date, biochemical parameters allowed more than 400 different G6PD variants to be distinguished thereby suggesting a vast genetic heterogeneity. So far, only a small portion of this heterogeneity has been confirmed at the DNA level with the identification of about 90 different point mutations in the G6PD coding sequence. To determine the molecular background of G6PD deficiency in Southeast Asian countries, we conducted molecular analyses of G6PD patients from the Philippines, Malaysia, Singapore, Vietnam and Indonesia. The most prevalent mutation identified differs from country to country, thus suggesting independent mutational events of the G6PD gene.
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PMID:Glucose-6-phosphate dehydrogenase deficiency: molecular heterogeneity in southeast Asian countries. 1590 15

Deficiency of glucose-6-phosphate dehydrogenase is a very common X-linked genetic disorder though most deficient people are asymptomatic. A number of different G6PD variants have reached polymorphic frequencies in different parts of the world due to the relative protection they confer against malaria infection. People, usually males, with deficient alleles are susceptible to neonatal jaundice, and acute hemolytic anemia, usually during infection, after treatment with certain drugs or after eating fava beans. Very rarely de novo mutations can arise causing the more severe condition of chronic nonspherocytic hemolytic anemia. Altogether 160 different mutations have been described. The majority of mutations cause red cell enzyme deficiency by decreasing enzyme stability. The polymorphic mutations affect amino acid residues throughout the enzyme and decrease the stability of the enzyme in the red cell, possibly by disturbing protein folding. The severe mutations mostly affect residues at the dimer interface or those that interact with a structural NADP molecule that stabilizes the enzyme.
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PMID:G6PD deficiency: the genotype-phenotype association. 1761 Oct 6

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common human enzyme defect, being present in more than 400 million people worldwide. The global distribution of this disorder is remarkably similar to that of malaria, lending support to the so-called malaria protection hypothesis. G6PD deficiency is an X-linked, hereditary genetic defect due to mutations in the G6PD gene, which cause functional variants with many biochemical and clinical phenotypes. About 140 mutations have been described: most are single base changes, leading to aminoacid substitutions. The most frequent clinical manifestations of G6PD deficiency are neonatal jaundice, and acute haemolytic anaemia, which is usually triggered by an exogenous agent. Some G6PD variants cause chronic haemolysis, leading to congenital non-spherocytic haemolytic anaemia. The most effective management of G6PD deficiency is to prevent haemolysis by avoiding oxidative stress. Screening programmes for the disorder are undertaken, depending on the prevalence of G6PD deficiency in a particular community.
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PMID:Glucose-6-phosphate dehydrogenase deficiency. 1875 69


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