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)

The negative consequences of parasitic infection (virulence) were examined for two lizard malaria parasite-host associations: Plasmodium agamae and P. giganteum, parasites of the rainbow lizard, Agama agama, in Sierra Leone, West Africa; and P. mexicanum in the western fence lizard, Sceloporus occidentalis, in northern California. These malaria species vary greatly in their reproductive characteristics: P. agamae produces only 8 merozoites per schizont, P. giganteum yields over 100, and P. mexicanum an intermediate number. All three parasites appear to have had an ancient association with their host. In fence lizards, infection with malaria is associated with increased numbers of immature erythrocytes, decreased haemoglobin levels, decreased maximal oxygen consumption, and decreased running stamina. Not affected were numbers of erythrocytes, resting metabolic rate, and sprint running speed which is supported by anaerobic means in lizards. Infected male fence lizards had smaller testes, stored less fat in preparation for winter dormancy, were more often socially submissive and, unexpectedly, were more extravagantly coloured on the ventral surface (a sexually dimorphic trait) than non-infected males. Females also stored less fat and produced smaller clutches of eggs, a directly observed reduction in fitness. Infected fence lizards do not develop behavioural fevers. P. mexicanum appears to have broad thermal buffering abilities and thermal tolerance; the parasite's population growth was unaffected by experimental alterations in the lizard's body temperature. The data are less complete for A. agama, but infected lizards suffered similar haematological and physiological effects. Infected animals may be socially submissive because they appear to gather less insect prey, possibly a result of being forced into inferior territories. Infection does not reduce clutch size in rainbow lizards, but may lengthen the time between clutches. These results are compared with predictions emerging from several models of the evolution of parasite virulence. The lack of behavioural fevers in fence lizards may represent a physiological constraint by the lizards in evolving a thermal tolerance large enough to allow elimination of the parasite via fever. Such constraints may be important in determining the outcome of parasite-host coevolution. Some theory predicts low virulence in old parasite-host systems and higher virulence in parasites with greater reproductive output. However, in conflict with this argument, all three malarial species exhibited similar high costs to their hosts.
 ...
PMID:Virulence of lizard malaria: the evolutionary ecology of an ancient parasite-host association. 223 62

Two cases of cerebral malaria with hyperkinetic shock are reported. The first case concerned a 39-year-old european male who was not taking any prophylactic anti-malarial drugs. After having had headache and fever for a week, he was admitted to the intensive care unit (ICU) in coma and with jaundice. His initial systolic blood pressure was 60 mmg, with a central venous pressure (CVP) of -3 cmH2O. Five-hundred ml of modified fluid gelatin increased the CVP without raising the blood pressure. Haemodynamic investigations revealed a cardiac index (CI) = 5.2 l.min-1.m-2, peripheral arterial resistances (Rsa) = 290 dyn.s.cm-5, oxygen consumption (VO2) = 120 ml.min-1.m-2. Despite treatment with dopamine and dobutamine, the patient died 3 h after his admission, with a CI of 1.9 l.min-1.m-2. The second patient was a 14-year-old senegalese girl, admitted in circumstances similar to the first case. Initial haemodynamic investigations gave the following figures: CI 6.5 l.min-1.m-2, Rsa = 476 dyn.s.cm-5, VO2 = 174 ml.min-1.m-2. Recovery was obtained with fluid replacement therapy and dopamine. In the absence of another associated infectious disease, the plasmodial origin of the septic shock would seem to be the most likely in both cases. Pathophysiological mechanisms of these algid forms of malaria remain enigmatic. Various factors are discussed: cytoadherence of erythrocytes infected with Plasmodium falciparum, immunological disturbances, or a specific endotoxin.
 ...
PMID:[Hyperkinetic shock and cerebral malaria]. 224 Jul

Supervision of health care centers is needed to ensure quality health care. Visits to health centers by supervisors should consist of 6 primary components: communication, teaching, seeing patients, tour of the health center, assessing performance, and follow up. Effective communication skills between the supervisor and health care workers is needed. Suggestions for good communication include regular and frequent visits, the same supervisor to encourage relationships between the supervisor and health center staff, and few cancellation of visits. Good communication is also dependent on the supervisor's attitude; criticism should be constructive. In teaching, information should be based on standard protocols and treatments. Teaching methods such as tutorials and discussions encourage group participation and are effective in solving problems. Common problems which should be discussed are child health issues such as coughs, diarrhea, fever, immunization, and nutrition; maternal health problems such as antenatal care, contraception, and labor management; communicable disease problems such as water supply and disposal, tuberculosis, and malaria; and sexually transmitted diseases. Seeing patients is the 3rd component of health center visits; this allows the supervisor to observe daily problems encountered by the staff and to teach workers. A tour of the health center should be conducted for the purpose of improving the center and should focus on water supply and disposal. The objectives of assessing performance is to identify problem areas which can be improved. This visit component can be conducted throughout the visit. Areas of assessment include clinical skills, dispensary, and health education. Data from records can be collected and utilized to demonstrate the center's effectiveness. At the end of the visit, problems should be identified and actions of improvement should be proposed. Follow up is important to correct deficiencies and problems.
 ...
PMID:Visit a health centre in a developing country. 224 54

A variety of tubular marker proteins, as compared to healthy controls, are excreted at an increased rate in the urine of patients with renal damage. Beside cytoplasmic glutathione-S-transferase and lysosomal beta-N-acetyl-glucosaminidase (beta-NAG) the majority of kidney-related urine proteins derives from membrane surface components of the most vulnerable proximal tubule epithelia, among them ala-(leu-gly)-aminopeptidase, gamma-glutamyl transpeptidase (GGT), the tubular portion of angiotensinase A, the major brush border glycoprotein 'SGP-240' and adenosine-deaminase-binding protein. Urinary tissue proteins, e.g. brush border (BB) microvilli, are immunologically identical with those antigens prepared from cell membranes of the human kidney itself. BB antigens are shed into the urine of patients with glomerulonephritis, interstitial nephritis, systemic diseases, e.g. systemic lupus erythematosus (SLE), diabetes mellitus and multiple myeloma, arterial hypertension, infectious diseases (malaria, AIDS) and after operations, renal grafting and administration of X-ray contrast media, aminoglycosides or certain cytostatics (cis-platinum). Tissue proteinuria of tubular proteins is determined by enzyme-kinetic or quantitative immunological assays applying either poly- or monoclonal antikidney antibodies. Clinical, ultrastructural and histochemical studies support the idea that both 'soluble' and high-molecular-weight membrane particles (vacuolar blebs, greater than 10(6) dalton) as well as microfilamental components of the epithelial cytoskeleton contribute to tubular 'histuria' which appears as a sensitive parameter in monitoring tubular damage under clinical conditions at a very early phase.
 ...
PMID:Urinary proteins of tubular origin: basic immunochemical and clinical aspects. 225 76

During the last years, imported diseases have become more frequent in Switzerland. This is easily explained by the enormous increase of tourism to tropical and subtropical countries. Immigration from these countries has equally seen an important augmentation. The principal imported diseases are still malaria and gastrointestinal infections. Viral infections are rarely diagnosed, with the exception of hepatitis and HIV infection. The prevalence of sexually transmitted diseases is most certainly underestimated. The differential diagnosis of imported skin diseases is still difficult. Rare tropical diseases will probably become more frequent in the coming years as travellers leave more and more the traditional tourist paths. Practitioners have to look out for such problems, and continuous training programmes for them will have to take these new problems into account. Referral centres of infectious diseases should be established in all regions of Switzerland. High priority should be given to the prevention of imported diseases.
 ...
PMID:[Imported diseases in Switzerland: development and perspectives]. 226 17

Monoclonal IgM rheumatoid factor-like anti-globulins were produced by in vitro stimulation of naive BALB/c spleen cells with lipopolysaccharide, and by hyperimmunization of mice with merozoites of Plasmodium falciparum, followed by fusion of the spleen cells to mouse myelomas. In vitro, these anti-globulins augmented the inhibitory effects of P. falciparum-specific polyclonal mouse sera and monoclonal IgG1 and IgG2b antibodies by binding to Fc fragments of IgG molecules attached to blood-stage parasites. In some instances, the presence of anti-globulins correlated with an increase in the number of schizonts which failed to disperse merozoites. In other cases, parasitaemia remained low in the absence of the schizont inhibition phenomenon, suggesting that anti-globulins contribute to host cell protection not only by agglutinating merozoites, but also by increasing the density of the antibody coat surrounding the parasites, thus interfering with parasite receptor-erythrocyte ligand interactions. The anti-globulins were not inhibitory when added to parasite cultures containing IgG not specific for P. falciparum. These results may help explain the function of IgM anti-globulins found at elevated serum levels in some patients with malaria or other chronic infectious diseases.
 ...
PMID:Monoclonal IgM rheumatoid factor-like anti-globulins enhance the inhibitory effects of Plasmodium falciparum-specific monoclonal antibodies in vitro. 226 12

A double blind study of daily doxycycline (100 mg) vs. weekly mefloquine (250 mg) was performed on United States soldiers training in Thailand to assess the effect of doxycycline malaria prophylaxis on the incidence of gastrointestinal infections. During a 5 week period, 49% (58/119) of soldiers receiving doxycycline and 48% (64/134) of soldiers receiving mefloquine reported an episode of diarrhea. Infection with bacterial enteric pathogens was identified in 39% (47/119) of soldiers taking doxycycline and 46% (62/134) of soldiers taking mefloquine. Forty-four percent (59/134) of soldiers receiving mefloquine and 36% (43/119) of soldiers receiving doxycycline were infected with enterotoxigenic Escherichia coli (ETEC), while 9% (12/134) of soldiers receiving mefloquine and 4% of soldiers receiving doxycycline were infected with Campylobacter. Side effects from either medication were minimal. After 5 weeks in Thailand, the percent of non-ETEC strains resistant to greater than or equal to 2 antibiotics increased from 65% (77/119) to 86% (95/111) in soldiers on mefloquine and from 79% (84/106) to 93% (88/95) in soldiers on doxycycline. Doxycycline prophylaxis did not prevent or increase diarrheal disease in soldiers deployed to Thailand where ETEC and other bacterial pathogens are often resistant to tetracyclines.
 ...
PMID:A comparative study of gastrointestinal infections in United States soldiers receiving doxycycline or mefloquine for malaria prophylaxis. 226 64

The vitamin A status of 454 pre-school age Congolese children was evaluated by the impression cytology method with transfer (ICT) and by the determination of plasma retinol. The absence of goblet cells and the presence of enlarged epithelial cells indicate a peripheral deficit of vitamin A. A level of plasma retinol lower than 10 micrograms/dl is an indicator of vitamin A deficiency. The subjects were children in good health or suffering from malaria, measles or various infectious diseases. Advantages, disadvantages, sensitivity and specificity of the ICT are discussed. We suggest its use in a mass screening program for vitamin A deficiency in developing countries.
 ...
PMID:Vitamin A deficiency in pre-school age Congolese children during malarial attacks. Part 1: Utilisation of the impression cytology with transfer in an equatorial country. 227 77

Travelers to developing countries are at risk of contracting tropical infectious diseases that they or their physicians may be unfamiliar with. Proper pre-travel counsel should be given concerning general health risks that may be encountered abroad, immunizations, malaria prophylaxis and prevention and treatment of traveler's diarrhea. In Rhode Island, expert advice may be obtained at the Traveler's Clinics at the Miriam Hospital in Providence (401-274-3700 or 331-8500, ext. 4075) and the Memorial Hospital in Pawtucket (401-722-6000, ext. 2545). The Miriam Traveler's Clinic is open Wednesday (9-1) and all day Friday while the Memorial Traveler's Clinic is open Tuesday afternoon. These Traveler's Clinics are headed by Drs G.R. Olds and S.M. Opal, respectively.
 ...
PMID:Travel to developing countries: pre-departure medical advice. 234 32

Case-control studies have been evoked as important alternatives to randomized clinical trials in the evaluation of infectious disease interventions. Using computer simulations, we compare the behaviour of common measures of association derived from case-control studies in the context of a malaria vaccine programme administered under complex transmission conditions. Several simplifying assumptions of previous workers have been relaxed and the simulated conditions are endemic rather than epidemic. The common estimators of association used in case-control studies remain unbiased only in limited circumstances. The term dependent happenings, first defined by Ross in 1916, is resurrected. Since the number of people becoming infected is dependent on the number of people already infected, control programmes in infectious diseases produce direct as well as indirect effects. Three different study designs with different pairs of comparison populations are defined. The choice of comparison population can be used to differentiate direct from indirect effects. In order to clarify the direct effects of a vaccination programme the comparison groups must be subjected to identical transmission intensities. In contrast, the referent group must remain unaffected by consequences of the intervention to determine indirect effects.
 ...
PMID:The behaviour of common measures of association used to assess a vaccination programme under complex disease transmission patterns--a computer simulation study of malaria vaccines. 235 14


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