Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0011570 (depression)
 172,036 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The present longitudinal study was designed to characterize immunosuppression during acute Plasmodium falciparum infection, during the treatment and up to 1 month after the acute stage. The proliferative responses of blood mononuclear cells (BMNC) isolated from non-immune and semi-immune malaria patients and controls to mitogens and two Plasmodium-derived stimulators (merozoites, Meroz, and soluble purified antigen, SPag) and non-related antigens were measured by [3H]thymidine incorporation. BMNC isolated before treatment (day 0) from the non-immune patients did not respond to Meroz, whereas those from controls showed a significantly higher response. The SPag responses were also low in BMNC isolated on day 0 and increased in both the non-immune and the semi-immune patients during the observation period. These findings indicate that during malaria there is a depression of the parasite-specific proliferative response. The subset composition of BMNC isolated from non-immune patients was studied in a FACS analyser. The mean cell volumes of both Leu 2+ and Leu 3+ cells were increased during the acute phase of the infection, indicating that malaria infection results in activation of both T-helper and T-suppressor cells. There was no overall reduction of the response to mitogens on day 0. However, 3 days after initiation of the treatment the mitogen response was decreased. This finding indicates that it is important to distinguish between the effects of malaria infection and of drug treatment.
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PMID:Suppression of parasite-specific response in Plasmodium falciparum malaria. A longitudinal study of blood mononuclear cell proliferation and subset composition. 242 16

Variation in susceptibility of the vector Anopheles stephensi Liston to the human malaria parasite Plasmodium falciparum (Welch) was demonstrated using twelve strains of mosquitoes and one strain of parasites cultured in vitro. The Beech strain of An. stephensi exhibited greatest natural refractoriness, but with high intrapopulation variability. By selection for the required characteristic, two refractory lines of the Punjab strain and one highly susceptible line of the Sind strain were obtained. The median number of oocysts in the two refractory lines was less than 4% of that in the unselected line, whilst the highly susceptible line yielded about twice as many oocysts as the unselected line. Selection progressed more by keeping the descendants of individual females separate and selecting between them (individual selection) rather than pooling the progeny of all selected mosquitoes (mass selection). Using the former procedure many lines were lost due to inbreeding depression, but the outcome was more successful.
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PMID:Selection of Anopheles stephensi for refractoriness and susceptibility to Plasmodium falciparum. 251 46

The Epstein-Barr virus (EBV), a B lymphotropic virus, is involved in a growing number of immunopathological disorders benign or malignant. The X-linked lymphoproliferative syndrome and its multifaceted clinical expression in a unique situation described in this issue by Purtilo. Among recent findings, the association between EBV and idiopathic interstitial pneumopathy (also named cryptogenic fibrosing alveolitis), is to be noted (6). From a molecular biology view-point, in vitro immortalization of B lymphocytes by EBV is under a pluri-genic (EBNA 2, EBNA 1, LYDMA) control. The role of EBV in oncogenesis appears different in Burkitt's Lymphoma (BL) and in nasopharyngeal carcinoma (NPC). In development of African BL, EBV appears to initiate the multistage carcinogenic event, through an early and massive infection. Other events include specific depression of T-cell immunity by hyperendemic malaria and c-myc onc-gene activation through chromosome translocation. In the genesis of NPC, the role of EBV still remain to be clarified although the strong and consistent association between EBV and the undifferentiated carcinoma of the nasopharyngeal (NPC) around the world favours an etiological relationship. The simple detection of IgA antibodies to VCA and EA allows early detection of the NPC, thus permitting a 95% cure rate at 5 years post-radiotherapy. Such an early diagnostic is of paramount public health importance. Furthermore, IgA/VCA and IgA/EA antibodies characterize precancerous conditions, giving the theoretical possibility of preventive interventions.
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PMID:The Epstein-Barr virus (EBV): a Rosetta Stone for understanding the role of viruses in immunopathological disorders and in human carcinogenesis. 299 May 89

Serum pools from mice undergoing lethal infection with Plasmodium berghei inhibit the growth of an IL2-dependent mouse cytotoxic T cell line (CTLL). A partially purified preparation of the inhibitory factor specifically inhibited IL2-mediated events such as IL2-dependent CTLL growth and the Con A mitogenic response of normal mouse spleen cells. Production of and response to IL1, as well as growth of myeloma lines, was not affected. Administration of the partially purified preparation to normal mice resulted in a significant depression in IL2 production, thereby indicating a role for the inhibitory factor in maintaining immune depression in malaria-infected mice.
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PMID:Characterization of a specific inhibitor of IL2-mediated proliferation from serum of Plasmodium berghei infected mice. 305 90

The toxicities of antimalarial drugs vary because of the differences in the chemical structures of these compounds. Quinine, the oldest antimalarial, has been used for 300 years. Of the 200 to 300 compounds synthesised since the first synthetic antimalarial, primaquine in 1926, 15 to 20 are currently used for malaria treatment, most of which are quinoline derivatives. Quinoline derivatives, particularly quinine and chloroquine, are highly toxic in overdose. The toxic effects are related to their quinidine-like actions on the heart and include circulatory arrest, cardiogenic shock, conduction disturbances and ventricular arrhythmias. Additional clinical features are obnubilation, coma, convulsions, respiratory depression. Blindness is a frequent complication in quinine overdose. Hypokalaemia is consistently present, although apparently self-correcting, in severe chloroquine poisoning and is a good index of severity. Recent toxicokinetic studies of quinine and chloroquine showed good correlations between dose ingested, serum concentrations and clinical features, and confirmed the inefficacy of haemodialysis, haemoperfusion and peritoneal dialysis for enhancing drug removal. The other quinoline derivatives appear to be less toxic. Amodiaquine may induce side effects such as gastrointestinal symptoms, agranulocytosis and hepatitis. The main feature of primaquine overdose is methaemoglobinaemia. No cases of mefloquine and piperaquine overdose have been reported. Overdose with quinacrine, an acridine derivative, may result in nausea, vomiting, confusion, convulsion and acute psychosis. The dehydrofolate reductase inhibitors used in malaria treatment are sulfadoxine, dapsone, proguanil (chloroguanide), trimethoprim and pyrimethamine. Most of these drugs are given in combination. Proguanil is one of the safest antimalarials. Convulsion, coma and blindness have been reported in pyrimethamine overdose. Sulfadoxine can induce Lyell and Stevens-Johnson syndromes. The main feature of dapsone poisoning is severe methaemoglobinaemia which is related to dapsone and to its metabolites. Recent toxicokinetic studies confirmed the efficacy of oral activated charcoal, haemodialysis and haemoperfusion in enhancing removal of dapsone and its metabolites. No overdose has been reported with artemesinine, a new antimalarial tested in the People's Republic of China. The general management of antimalarial overdose include gastric lavage and symptomatic treatment.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Clinical features and management of poisoning due to antimalarial drugs. 330 66

Climatic changes must have greatly affected the distribution of malaria in prehistoric times. Paleobotanical evidence, snowline depression studies and information obtained from deep sea sediment cores, indicate that southern Europe must have suffered a drop of summer temperatures of approximately 9 degrees C during the last glacial maximum, 18,000 years ago. Such a drop would have been decisive as regards the distribution of malaria and its vectors. If present at all, the disease would have been confined to the southernmost parts of the continent but P. falciparum and today's most effective vectors--A. labranchiae and A. sacharovi--would have been excluded from Europe. In western Asia, summer temperatures 6 degrees C lower than those of today would have had less effect on the malaria situation. The introduction of falciparum malaria in southern Europe is placed in Hellenistic and Early Imperial Roman times, based on paleoclimatological evidence and historical and medical data. In America P. falciparum is also considered a late entrant but vivax and quartan malaria may have been introduced in pre-Columbian times. In the Pacific, the disease is known to have been spread by man since the Age of Discovery until contemporary times.
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PMID:Changes in the geographical distribution of malaria throughout history. 333 82

Thirty children acutely infected by Plasmodium falciparum and suffering either benign uncomplicated malaria (17 cases), or cerebral malaria (13 cases), were investigated for T-cell number and subset distribution among peripheral blood mononuclear cells using OKT3, OKT4, and OKT8 monoclonal antibodies, and for natural killer (NK) activity using K562 cells as targets. They were compared to a group of 16 age- and sex-matched healthy Senegalese children. OKT8 cell percentage was found increased in both groups of patients with a decrease of OKT4 cell percentage in cerebral malaria patients only. Both groups thus exhibited a decreased OKT4/OKT8 ratio, which was slightly lower in cerebral malaria cases than in benign cases. NK activity was found elevated in uncomplicated cases of malaria, in contrast to patients suffering cerebral malaria, who exhibited a profound depression of NK activity.
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PMID:T-cell subsets and natural killer activity in Plasmodium falciparum-infected children. 351 Jan

Spleen cells from mice immune to Plasmodium berghei exhibited a significantly increased in vitro proliferative response to parasitized reticulocytes compared to spleen cells from normal mice. The specific response to malaria antigen was decreased in spleen cells from pregnant immune mice in contrast to the nonspecific response to the mitogen phytohemagglutinin. Addition of mouse serum to spleen cell cultures of immune mice depressed both the phytohemagglutinin and the specific proliferative response, whereas serum of pregnant mice exerted an even stronger inhibition than serum of nonpregnant mice. Charcoal adsorption of mouse sera for the elimination of steroid hormones removed the serum dependent immunosuppression from normal as well as pregnant serum. Corticosterone added to the spleen cell cultures depressed also the proliferative response. These findings demonstrate that the response to malaria antigen is decreased in immune mice during pregnancy. The possible effect of serum corticosterone on the depression of the immune response is discussed.
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PMID:Plasmodium berghei: reduction of the mouse's specific lymphoproliferative response in relation to corticosterone and pregnancy. 352 63

This paper reports the results of in vitro experiments which attempt to elucidate the mechanisms whereby Gambian children control acute infections of Plasmodium falciparum. It was shown initially that mononuclear cells from children with acute malaria, in the presence of specific antibody, caused a marked reduction in in vitro parasite growth. IgM antibodies appeared to be considerably more effective than IgG. T or B lymphocytes were ineffective in the system; adherent cells alone had some effect, but much less than the unfractionated cell population. Adherent cells were however fully effective after exposure to supernatants from T cells activated either non-specifically by phytohaemagglutinin (PHA), or specifically by P. falciparum antigens. Depression of parasite growth was also observed, independent of anti-malarial antibody. This was achieved when adherent cells from healthy Europeans, as well as those from infected children, were exposed to the supernatants from previously stimulated T cells before adding to the culture. Furthermore, intra-erythrocytic parasite death occurred after a short exposure to the supernatants of 'activated' adherent cells from both infected children and Europeans.
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PMID:Cellular mechanisms involved in recovery from acute malaria in Gambian children. 354 9

The host response to Plasmodia includes the production of enlarged populations of peripheral blood monocytes and tissue macrophages in the spleen and the liver. Since the hyperplasia of the mononuclear phagocyte system is believed to arise as a consequence of an enhanced blood monocyte influx, we tested monocyte chemotactic responsiveness in 19 patients with acute primary attack malaria. In addition, the neutrophil chemotaxis was measured in 12 patients. Before the initiation of antimalarial treatment a significant depression of monocyte chemotaxis was observed in approximately half of the patients when compared with healthy control subjects. The depression was found in Plasmodium falciparum malaria as well as in P. vivax or P. ovale malaria patients. The defective responsiveness was not receptor specific, since the responses towards casein and zymosan activated serum proved to be equally suppressed. The monocyte chemotaxis was followed in 14 of the patients, during treatment and after complete recovery. After 3 days of treatment the response had improved in most of the patients, and after 7 days all patients had a normal monocyte chemotaxis, which remained normal after one month. No significant differences between P. falciparum and P. vivax/ovale malaria was observed with respect to blood monocyte chemotactic responsiveness. Neutrophil chemotaxis in patients with P. falciparum infections was similarly suppressed before treatment (54% of controls), was still defective after 3 days of treatment, and nearly normalized after 7 days (87% of controls). Furthermore, monocyte phagocytic and candidacidal activities were assessed in the same patients on admission and during the follow-up. In contrast to chemotaxis, these functions were normal in all of the patients whenever measured. In conclusion, not all cell functions were altered in concert, and the previously unreported suppression of chemotactic migration might reflect a change in blood leucocyte subpopulations, deactivation in vivo or a direct suppressive effect of plasmodia induced products.
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PMID:Suppression of blood monocyte and neutrophil chemotaxis in acute human malaria. 380 53


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