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

Fifty-four cases of malaria in children seen during an 11-year period are described. There have been more cases seen in recent years, and the proportion of Plasmodium falciparum malaria has increased. Compliance with chemoprophylaxis is poor, but compliance does not guarantee protection. Malaria is the primary diagnostic consideration in any child recently returning from an endemic area who presents with fever. Two cases are described.
 ...
PMID:Malaria in children. 218 13

Proguanil and pyrimethamine are antifolate drugs with distinct chemical structures that are used commonly in the prophylaxis and treatment of Plasmodium falciparum malaria. Clinical reports and field studies have suggested that some parasites refractory to proguanil can be treated with pyrimethamine, and vice versa. Analysis of the P. falciparum dihydrofolate reductase (DHFR) from different parasites reveals the structural basis for differential susceptibility to these antifolate drugs. Parasites harboring a pair of point mutations from Ala-16 to Val-16 and from Ser-108 to Thr-108 are resistant to cycloguanil (the active metabolite of proguanil) but not to pyrimethamine. A single Asn-108 mutation, on the other hand, confers resistance to pyrimethamine with only a moderate decrease in susceptibility to cycloguanil. Significant cross-resistance to both drugs occurs in parasites having mutations that include Ser-108----Asn-108 and Ile-164----Leu-164. These results reflect the distinct structures of pyrimethamine and cycloguanil and suggest fine differences in binding within the active site cavity of DHFR. Alternative inhibitors, used alone or in combination, may be effective against some strains of cycloguanil- or pyrimethamine-resistant malaria.
 ...
PMID:Molecular basis of differential resistance to cycloguanil and pyrimethamine in Plasmodium falciparum malaria. 218 22

With the increased spread of chloroquine-resistant Plasmodium falciparum malaria and mounting evidence of lack of efficacy and toxicity of alternative drugs, it has become extremely difficult to propose simple, widely applicable and uniformly acceptable recommendations for malaria chemoprophylaxis. With regard to specific drugs, it is clear that because of its toxicity amodiaquine should no longer be used for chemoprophylaxis, and that pyrimethamine/sulfadoxine should, for the most part, be used only as a presumptive therapy. The pyrimethamine/dapsone combination is promising, but data on its efficacy are limited. Although proguanil (chloroguanide) is recommended by several sources because of its safety, disturbing reports of chemoprophylaxis failure in Africa and a well-documented lack of efficacy in South East Asia would suggest that its usefulness may be limited. However, a recent study has documented the efficacy of a proguanil-sulphonamide combination in Thailand, an area of high grade chloroquine resistance. Although long term studies of drug safety are not yet available, doxycycline and mefloquine appear to be the drugs of choice in areas where P. falciparum shows multidrug resistance. Regardless of the drug regimen recommended for chemoprophylaxis, travellers must be informed that no present-day antimalarial agent guarantees protection against malaria.
 ...
PMID:Prevention of malaria. 218 5

Chloroquine is currently the drug of choice for treatment of acute attacks of Plasmodium falciparum malaria in chloroquine-sensitive areas. In areas of low level resistance, this drug may still be used (25 mg/kg of body weight in three days) in semi-immune patients. In case of failure, or in areas of high level resistance, quinine (25 mg/kg/day for 3 to 5 days) or, in spite of increasing resistance, Fansidar should be prescribed. Mefloquine, Fansimef and Halofantrine ought to be strictly prescribed to delay occurrence of resistance. Severe attacks require quinine by continuous intravenous infusion. Spleen enlargement does not usually require specific treatment unless poor tolerance is observed. Blood transfusions present a considerable risk of HIV transmission. Appropriate malaria treatment may avoid blood transfusions thus preventing HIV dissemination in Africa.
 ...
PMID:[Treatment of Plasmodium falciparum malaria in Africa (except cerebral malaria)]. 219 75

The authors compare the respective therapeutic efficiency of chloroquine and amodiaquine in the treatment of Plasmodium falciparum malaria fever in urban dispensaries. Chloroquine has a constant rate of efficiency, whatever dosage and duration of treatment be and should be saved for home presumptive treatment of malaria fever. Amodiaquine at a dose of 35 mg/kg in 3 days leads to a noticeable clinical success (96.5 p.c.). It should be selected as drug of first to treat any malaria fever case biologically confirmed, in urban dispensaries.
 ...
PMID:[Evaluation of the efficacy of amino 4-quinolones in a chemoresistant zone. Proposals for new therapeutic schemes]. 219 76

The review deals with analysis of the literature data concerning the importance of valine substitution in certain proteins, namely p21 ras and hemoglobin. A model of the active site of p21 protein is discussed in the light of GTPase activities alterations as a result of monoaminoacid substitution in conservative sites of p21 protein. The established relationship between some forms of transformation and Plasmodium falciparum malaria on the molecular level is shown in a new aspect. The widespread opinion that Hb S is valid as the means of malaria resistance is questioned in terms of new molecular data.
 ...
PMID:[Valine substitution]. 219 88

The esters of cephalotaxine-harringtonine, homoharringtonine and deoxyharringtonine--have been reported by both Chinese and American oncologists as useful in the treatment of human nonlymphoblastic leukaemias and selected solid tumours of the head and neck. We report our results with homoharringtonine, currently a Phase II clinical trial drug with the National Cancer Institute, in the treatment of malaria. Homoharringtonine, 2.7-3.4 nM, was effective in causing 50% growth inhibition of two strains of chloroquine-resistant Plasmodium falciparum malaria in vitro. In vivo tests in mice infected with P. yoelii showed that this drug was effective in inhibiting parasite growth in this system as well. Histologically, the drug was associated with karyorrhexis. Drug-exposed cells showed decreased levels of putrescine and spermidine and increased spermine levels. Our findings not only demonstrate the potential usefulness of homoharringtonine in the treatment of chloroquine-resistant malaria, but also demonstrate the advantage of applying comparative biochemistry and an understanding of biological mechanisms in a rational approach to the development and treatment of diseases including malaria.
 ...
PMID:Treatment of chloroquine-resistant malaria with esters of cephalotaxine: homoharringtonine. 222 25

In sub-Saharian Africa, most HIV seropositive subjects carry either haematozoa (especially children) or antimalarial antibodies. Despite a transient decrease in cell-mediated immunity during malarial paroxysms, Plasmodium falciparum malaria does not seem to influence the course of the HIV infection. Paroxysms may be slightly more frequent or slightly more severe in HIV seropositive subjects, but they raise no diagnostic or therapeutic problem. Some cases of HIV contamination have been attributed to the blood transfusions required by malaria-induced anaemia. Prophylactic measures include early chemotherapy of malaria and detection of dangerous blood donors, if necessary by quick tests. Modern HIV tests avoid most of the false-positive reactions sometimes observed during malaria.
 ...
PMID:[HIV infection and malaria]. 223 21

The frequency of asymptomatic malaria parasitaemia was investigated in rural and urban school-children aged six to 12 years in southwestern Nigeria between January 1987 and October 1988. Asymptomatic parasitaemia was detected in the rural school-children all year round with the lowest parasite rate in January and the highest in July, corresponding to the mid-dry and wet seasons respectively. Asymptomatic parasitaemia was also common amongst urban school-children, but the frequency was lower than in the rural children. Parasite density was less than or equal to 1000 microliters-1 in 42% of parasite-positive asymptomatic children and was greater than 10,000 microliters-1 in only 20% of them. Mass treatment with chloroquine, to which the parasites were fully sensitive, was followed by the same rate of re-infection in the parasite-positive and parasite-negative groups. Of 7713 patients clinically diagnosed as having malaria 4425 were found to have parasitologically-proven malaria, and of these 4239 had pure Plasmodium falciparum malaria. Of the patients with falciparum malaria only 4.6% were below the age of one year. In 47% the parasite count was less than or equal to 1000 microliters-1, and it was over 10,000 microliters-1 in 37% and over 250,000 microliters-1 in 16%. There was no significant difference between the asymptomatic children and the acutely ill patients in the percentage with parasite densities less than or equal to 1000 microliters-1, but the percentage with parasite densities greater than 10,000 microliters-1 was significantly greater in the acute malaria patients than in those with asymptomatic parasitaemia.
 ...
PMID:Malaria in Nigeria: a revisit. 225 67

The relation between Plasmodium falciparum malaria and symptomatic human immunodeficiency virus 1 (HIV-1) infection was investigated in paediatric and adult patients in Kampala, Uganda, from 1987 to 1989. Both infections contributed largely to hospital morbidity. Of 1527 clinically suspicious in-patients, 61% were positive for HIV-1 infection. 52% of patients with positive HIV-1 serology fulfilled the World Health Organization clinical case definition for acquired immune deficiency syndrome (AIDS) in Africa. No association could be found between HIV-1 infection and malaria either in paediatrics or in adults. P. falciparum parasitaemia was present in 18% of all patients and no differences in prevalence of malaria infection or in parasite density could be demonstrated between HIV-1 positive and HIV-1 negative patients. The comparison of clinical symptoms showed typical differences in AIDS-related morbidity but no difference in malaria-specific morbidity. Also, the response to malaria treatment was the same in HIV-1 positive and HIV-1 negative patients. P. falciparum malaria does not appear to act as an opportunistic agent in AIDS patients in Uganda.
 ...
PMID:The clinical and parasitological presentation of Plasmodium falciparum malaria in Uganda is unaffected by HIV-1 infection. 226 Jan 60


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>