| identification of a putative plasmodium berghei (a rodent malaria parasite) reticulocyte receptor. | | 1990 | 2199274 |
| antibody-independent inhibition of plasmodium falciparum in vitro cultures. | the sera of 100 colombian individuals of african origin living in a malaria-endemic area of the pacific coast were studied with regard to their capacity to inhibit plasmodium falciparum cultures in vitro. antimalarial antibody levels determined by indirect immunofluorescence were higher in the group of infected individuals than in the noninfected individuals, and inhibitory activity assessed by the inhibition of parasite incorporation of 3h-hypoxanthine in vitro was present in the sera of both t ... | 1990 | 2199491 |
| longitudinal survey in an endemic region of plasma soluble interleukin-2 receptor and antibody levels in plasmodium falciparum malaria. | a survey involving 81 individuals living in dafinso and vallée du kou no. 4 (near bobo-dioulasso), burkina faso, was performed in june 1987, august to september 1987, and january 1988, respectively, at the beginning of, during, and after the transmission season of malaria. the clinical longitudinal study during the transmission period allowed us to define three different groups in terms of both age and occurrence of malaria attack (5,000 plasmodium falciparum per mm3 of blood and axillary fever ... | 1990 | 2199518 |
| congenital malaria in one identical twin. | | 1990 | 2199541 |
| [imported malaria. the description of a rare clinical case]. | | 1990 | 2199854 |
| permethrin-impregnated curtains and bed-nets prevent malaria in western kenya. | the effectiveness of permethrin-impregnated (0.5 g/m2) bed-nets and curtains as malaria control measures was evaluated in uriri, kenya in 1988. one hundred five families were randomly assigned to 1 of 3 study groups (control, bed-net, or curtain). all participants were cured of parasitemia with pyrimethamine/sulfadoxine. selective epidemiologic and entomologic parameters were measured weekly, while knowledge, attitude, and practices surveys were conducted at the beginning and end of the 15 week ... | 1990 | 2200287 |
| typing of southern african isolates of plasmodium falciparum using monoclonal antibodies. | antigenic diversity among 19 southern african isolates of plasmodium falciparum was demonstrated using a panel of 9 monoclonal antibodies. parasites obtained from single patients were heterogeneous. the antigen composition of 9 isolates was not stable with time in culture, particularly not with respect to 4 of the monoclonal antibodies. by the end of the investigation, 70% of isolates displayed an identical antigen pattern which was markedly different to any obtained in other parts of the world. ... | 1990 | 2200288 |
| natural malaria infections in anophelines in rondonia state, brazilian amazon. | the use of an immunoassay for the detection of plasmodium falciparum and p. vivax circumsporozoite (cs) antigens in anophelines has recently incriminated other malaria vectors besides anopheles darlingi in the brazilian amazon. in this study we analyzed 12,336 field-collected anophelines from endemic areas in rondonia for plasmodial infection. sixty-one specimens from 6 species were positive: 47 an. darlingi, 5 an. triannulatus, 4 an. albitarsis, 2 an. braziliensis, 2 an. strodei, and 1 an. oswa ... | 1990 | 2200290 |
| antimalarial activity of a 4',5'-unsaturated 5'-fluoroadenosine mechanism-based inhibitor of s-adenosyl-l-homocysteine hydrolase. | a 4',5'-unsaturated 5'-fluoroadenosine inhibitor of s-adenosyl-l-homocysteine hydrolase (sah hydrolase; ec 3.3.1.1), mdl 28842, was found to inhibit markedly the growth of plasmodium falciparum in vitro and plasmodium berghei in mice. inhibition of p. berghei growth was associated with a large increase in the concentration of s-adenosyl-l-homocysteine (sah) in the erythrocytes of the mice treated with mdl 28842. this increase in sah was due apparently to inhibition of the mouse erythrocyte sah h ... | 1990 | 2200410 |
| protein phosphorylation during the asexual life cycle of the human malarial parasite plasmodium falciparum. | recent evidence has suggested that extensive changes in the phosphorylation profile of red cell membrane proteins are associated with the invasion and development of the malarial parasite. in order to further define the role of parasite protein phosphorylation in these events we have looked at this phosphorylation using: (1) continuous metabolic labelling with [32p]orthophosphate, (2) pulse-labelling with [32p]orthophosphate and [35s]methionine, (3) autophosphorylation of infected cells using [g ... | 1990 | 2200523 |
| ultrastructural study on the erythrocytic schizogony of plasmodium vivax. | erythrocytic schizogony is initiated by repeated division of the nucleus in rapid sequence. another important feature of the developing schizont is the reappearance of segments of thick inner membrane and formation of lobes around these segments. these bulbous protuberances signal the start of budding process which ends in complete segmentation of the cell. the cytoplasmic organelles which de-differentiate at the beginning of trophozoite stage are formed again. asynchrony during merozoite format ... | 1990 | 2200724 |
| micro in vitro assessment of plasmodium falciparum sensitivity to chloroquine and mefloquine in gujarat. | micro in vitro tests conducted in 1987 in surat district of gujarat on sensitivity status of p. falciparum to chloroquine and mefloquine revealed that the parasite has developed resistance to chloroquine upto 32 pmol. the ed 99 in hazira, gothan and umra areas of the district was found to be 17.3, 18.5 and 8.7 pmol/well for chloroquine and for mefloquine it was 14.5, 4.8 and 6.8 pmol/well respectively. monitoring of p. falciparum resistance is indicated under national malaria eradication program ... | 1990 | 2200725 |
| radical treatment of vivax malaria in madhya pradesh, india. | | 1990 | 2200726 |
| evidence for a switching mechanism in the invasion of erythrocytes by plasmodium falciparum. | the human malaria parasite plasmodium falciparum demonstrates variability in its dependence upon erythrocyte sialic acid residues for invasion. some lines of p. falciparum invade neuraminidase-treated or glycophorin-deficient red blood cells poorly, or not at all, while other lines invade such cells at substantial rates. to explore the molecular basis of non-sialic acid dependent invasion, we selected parasite lines from a clone (dd2) that initially exhibited low invasion of neuraminidase-treate ... | 1990 | 2200806 |
| role of delayed type hypersensitivity responses in protection during chronic plasmodium berghei infection as evidenced by homing of radiolabelled bone marrow cells and contact sensitivity. | a comparative study of specific and non-specific immunosuppression has been carried out in acute and chronic plasmodium berghei infected mice in an in vivo system. in our previous studies, immunosuppression during acute p. berghei infection was attributed to t lymphocytes when we studied modulation of blastogenic response of lymphocytes in an in vitro system. in the present study, delayed type hypersensitivity (dth) was evident from the homing of radiolabelled bone marrow cells into the delayed ... | 1990 | 2200902 |
| [malaria and retinal hemorrhages]. | a 24-year-old woman presented with retinal hemorrhages, back from a travel in cameroon. she took a chloroquine chemoprophylaxis. we diagnosed a malaria due to plasmodium falciparum with anemia, splenomegaly and low parasitemia. a speedy clinical and ophthalmological recovery was obtained with mefloquine therapy. we discuss physiopathology of such uncommon retinal damage during malaria. | 1990 | 2200939 |
| characterisation and sequence of a protective rhoptry antigen from plasmodium falciparum. | we have recently demonstrated that a non-polymorphic rhoptry antigen, rap-1 (rhoptry associated protein-1), which is recognised by human immune serum, can successfully protect saimiri monkeys from a lethal infection of plasmodium falciparum malaria. in this report we further characterise the antigen, which consists of four major proteins of 80, 65, 42 and 40 kda and two minor proteins of 77 and 70 kda, and present the antigen's gene sequence. monoclonal antibody evidence, autocatalytic processin ... | 1990 | 2200961 |
| expression and characterization of glucose-6-phosphate dehydrogenase of plasmodium falciparum. | glucose-6-phosphate dehydrogenase (g6pd) from plasmodium falciparum has been detected previously in cultures of parasites grown in g6pd-deficient red blood cells. using polyacrylamide gel electrophoresis, a semi-quantitative assay has been developed to compare the level of the parasite enzyme activity in g6pd normal and in g6pd-deficient host cells. the results do not support the previous contention that the host cell g6pd-deficiency necessarily affects the level of expression of the parasite en ... | 1990 | 2200964 |
| [tropical malaria; does prophylaxis become simpler?]. | | 1990 | 2200971 |
| hypoglycaemia in sudanese children with cerebral malaria. | | 1990 | 2201015 |
| missing infections in aids. | in north america and europe, the opportunistic infections from which patients with acquired immune deficiency syndrome (aids) frequently suffer are pneumocystis carinii pneumonia and mycobacterium avium-intracellulare: in central africa these infections are uncommon or non-existent. serious infections with entamoeba histolytica and strongyloides stercoralis would be expected to occur in aids patients: they do not. falciparum malaria might be expected to interact with hiv infection: it does not. ... | 1990 | 2201111 |
| structure-activity relationships of analogs of pentamidine against plasmodium falciparum and leishmania mexicana amazonensis. | the antiprotozoal compound 1,5-di(4-amidinophenoxy)pentane (pentamidine) and 36 of its analogs were screened for in vitro activity against leishmania mexicana amazonensis clone 669 c4s (mhom/br/73/m2269) and plasmodium falciparum clones w2 (indochina iii/cdc) and d6 (sierra leone i/cdc). pentamidine and each of the analogs tested exhibited activity in vitro against l. m. amazonensis and p. falciparum. the pentamidine analogs were more effective against the p. falciparum clones than against l. m. ... | 1990 | 2201254 |
| in vitro susceptibilities of plasmodium falciparum to compounds which inhibit nucleotide metabolism. | a unique metabolic feature of malaria parasites is their restricted ability to synthesize nucleotides. these parasites are unable to synthesize the purine ring and must therefore obtain preformed purine bases and nucleosides from the host cell, the erythrocyte. on the other hand, pyrimidines must be synthesized de novo because of the inability of the parasites to salvage preformed pyrimidines. thus, one would anticipate that the blockage of purine salvage or pyrimidine de novo synthesis should a ... | 1990 | 2201255 |
| glucose-6-phosphate dehydrogenase from plasmodium berghei: kinetic and electrophoretic characterization. | evidence is given for the existence of a parasite-specific glucose-6-phosphate dehydrogenase in plasmodium berghei by characterization of its kinetic and electrophoretic properties. after separating the parasites from infected rbc the g6pd was purified by affinity chromatography with 2'5'-adp-sepharose 4b. in cellulose acetate electrophoresis malarial g6pd significantly differs from the red cell enzyme. the subunits of the parasite-specific g6pd have a molecular weight of 55 kd in contrast to 59 ... | 1990 | 2201291 |
| nucleotide status in erythrocytes of rats infected with pl. berghei. | nucleotide concentrations in erythrocytes of rats infected with plasmodium berghei were measured by ion-pair reversed-phase hplc. utp and gtp levels were higher in highly infected red blood cells obtained after density separation. the infected red blood cells possess higher hypoxanthine, adenine, and adenosine levels. | 1990 | 2201292 |
| kinetic modelling of the response of plasmodium falciparum to chloroquine and its experimental testing in vitro. implications for mechanism of action of and resistance to the drug. | the antimalarial mode of action of chloroquine (cq) has been investigated in great detail in recent years, but the overall mechanism is still controversial. instead of further probing the molecular aspects of partial reactions, a model based on the weak base properties of cq and its delta ph-driven accumulation in acid parasite compartments has been devised, and the integrated response of the parasite to the drug under different experimental conditions has been assayed to verify the validity of ... | 1990 | 2201299 |
| malaria. deaths from malaria acquired in africa. | | 1990 | 2201391 |
| world malaria situation 1988. part i. overview. | | 1990 | 2201393 |
| world malaria situation 1988. part ii. asia. | | 1990 | 2201394 |
| airport malaria. | | 1990 | 2201395 |
| guidelines for malaria prevention revised to include primary role for mefloquine. | | 1990 | 2201477 |
| a malaria heat-shock-like determinant expressed on the infected hepatocyte surface is the target of antibody-dependent cell-mediated cytotoxic mechanisms by nonparenchymal liver cells. | cultured hepatic stages of plasmodium falciparum and p. yoelii and with a monoclonal antibody recognizing a c-terminal fragment of the p. falciparum heat-shock-like protein (pfhsp70) revealed that synthesis of this antigen first occurs during intrahepatic development of the parasite, at the two nuclei stage. using a variety of techniques, including scanning electron microscopy, we observed that this antigenic determinant was expressed on the infected hepatocyte membrane. its participation in ant ... | 1990 | 2201546 |
| a multiple antigen peptide from the repetitive sequence of the plasmodium malariae circumsporozoite protein induces a specific antibody response in mice of various h-2 haplotypes. | the major repetitive epitopes of the surface circumsporozoite (cs) protein of malaria sporozoites represent candidates for the development of subunit vaccines against malaria. however, previous experimental work has shown that repetitive peptides from the cs proteins of plasmodium falciparum, p. vivax, p. yoelii and p. berghei are immunogenic only in mice with the h-2b or h-2k haplotype. this led to the conclusion that strong t helper epitopes from the non-repetitive cs sequences were required i ... | 1990 | 2201549 |
| two soluble antigens of plasmodium falciparum induce tumor necrosis factor release from macrophages. | the production of cytokines such as tumor necrosis factor (tnf) may contribute to the pathology of malaria. we showed previously that crude preparations of heat-stable exoantigens from parasite cultures induce the release of tnf in vitro and in vivo. when separated from the culture medium by affinity chromatography, in which immune immunoglobulin g was used as ligand, the mixture of exoantigens of plasmodium falciparum retained the capacity to induce the secretion of tnf, both by human monocytes ... | 1990 | 2201638 |
| effect of plasmodium falciparum on the survival of naturally infected afrotropical anopheles (diptera: culicidae). | the effect of the malarial parasite, plasmodium falciparum welch, on the daily survival rates and longevity of anopheles gambiae giles sensu lato and anopheles funestus giles was determined for wild-caught, naturally infected females from western kenya. mosquitoes were collected inside houses and held in cages until death, after which they were assayed for p. falciparum circumsporozoite protein by an enzyme-linked immunosorbent assay (elisa). survival rates of field populations determined by par ... | 1990 | 2201768 |
| interpretation of low-level plasmodium infection rates determined by elisa for anophelines (diptera: culicidae) from egyptian oases. | plasmodium infection rates determined by enzyme-linked immunosorbent assay (elisa) were compared for anopheles sergentii (theobald) and an. multicolor cambouliu in siwa oasis, egypt, an area with low-level plasmodium vivax transmission, and in bahariya and farafra, two other egyptian oases which appear to be free of malaria. initial testing indicated that 4.4% (23 of 518) and 0.8% (4 of 518) of the an. sergentii were positive for p. vivax and p. falciparum, respectively, and that 1.4% (1 of 71) ... | 1990 | 2201771 |
| plasmodium falciparum hyperparasitaemia: use of exchange transfusion in seven patients and a review of the literature. | during the last 15 years, at least 35 patients with severe falciparum malaria or babesiosis have recovered following treatment by exchange of up to 10 l of blood. in a patient treated in manchester, a parasitaemia of 2.10 x 10(6) microliters (42 per cent) was virtually eliminated over eight hours by a 3.5 litre exchange blood transfusion. however, the equipment and amounts of compatible blood required for total exchange are rarely available in areas endemic for malaria and the risks of the proce ... | 1990 | 2201995 |
| the epidemiology of drug-resistant malaria. | | 1990 | 2202097 |
| antibodies to the ring-infected erythrocyte surface antigen and the circumsporozoite protein of plasmodium falciparum in a rural community from burkina faso. | a population-based study in burkina faso was conducted to determine, under conditions of natural exposure to malaria parasites, the prevalence rate and seasonal variation of antibodies to the repeated amino acid sequences of the plasmodium falciparum ring-infected erythrocyte antigen (resa) and the circumsporozoite (cs) protein, and the relationship of the presence of malaria parasites in the blood with the level of these antibodies. a random sample of households was selected and visited twice d ... | 1990 | 2202098 |
| a comparison of two dna probes, one specific for plasmodium falciparum and one with wider reactivity, in the diagnosis of malaria. | the sensitivity and specificity of 2 probes for the detection of malarial infection was studied. 399 blood samples from gambian children were tested in a deoxyribonucleic acid (dna) hybridization assay, and the results compared with the microscopical findings from thick blood films. 8 additional pure plasmodium malariae and 14 pure p. vivax samples were also assayed. one probe, containing a 21 base pair tandem repeat and highly specific for p. falciparum, detected this species in all except 2 of ... | 1990 | 2202099 |
| intrinsic individual differences in circumsporozoite antibody response at a hyperendemic malaria focus. | antibody to the repetitive domain of the plasmodium falciparum circumsporozoite (cs) protein was measured in blood collected over 3 consecutive months from 224 residents of a hyperendemic focus in thailand. an enzyme-linked immunosorbent assay incorporating the protein ([nanp]15 + nvdp)2 was used. more than 22% of adults produced high antibody titres in all 3 months, even though transmission had stopped. malaria prevalence in these high-responders was the same as in the rest of the population an ... | 1990 | 2202100 |
| an estimation of the number of malaria sporozoites ejected by a feeding mosquito. | restrained anopheles stephensi mosquitoes infected with plasmodium falciparum were made to produce time-dependent series of saliva droplets in mineral oil. the relative volume of each droplet and the number of sporozoites each contained were determined microscopically; gland sporozoites were estimated with an enzyme-linked immunosorbent assay. median gland infection was 8170 and median number of sporozoites ejected was 15 (range, 0-978). inoculum size was positively correlated to the number of s ... | 1990 | 2202101 |
| inhibition of plasmodium falciparum growth by a synthetic iron chelator. | the susceptibility of the chloroquine-resistant malaria parasite plasmodium falciparum (fcr-3) to a pyridoxal-based iron chelator was tested. 10 microm of the chelator 1[n-ethoxycarbonylmethyl-pyridoxy-lidenium]-2-[2'-pyri dyl] hydrazine bromide (code name l2-9) effectively inhibited growth in vitro of the parasites. presaturation of the chelator with either ferric or ferrous iron partially blocked the inhibitory effect. two hours' exposure of parasites to 20 microm l2-9 was sufficient to inhibi ... | 1990 | 2202102 |
| cluster of chloroquine-resistant plasmodium falciparum malaria cases among short-term travellers to sierra leone. | | 1990 | 2202103 |
| sensitivity of plasmodium falciparum to chlorproguanil in gambian children after five years of continuous chemoprophylaxis. | | 1990 | 2202104 |
| malaria transmission and vector biology in manarintsoa, high plateaux of madagascar. | to evaluate the factors which determine the transmission level of falciparum malaria, entomological and parasitological surveys were conducted from october 1988 to february 1990 in manarintsoa in the central highland plateaux of madagascar. mosquitoes were collected for 928 man-nights in pit shelters and indoor resting sites. malaria vectors were anopheles arabiensis and an. funestus, with no evidence of the presence of an. gambiae sensu stricto. vectors were mainly exophilic and zoophilic. the ... | 1990 | 2202220 |
| enzyme immunoassays for detection of malarial antigens in human plasmas by plasmodium falciparum monoclonal antibodies. | the screening of blood donors for the detection of dangerous disease carriers is a mandatory requirement for blood transfusion centers. enzyme immunoassay (eia) is a suitable method for the examination of large populations. we describe a sandwich eia allowing the detection of soluble malarial antigens in plasma using 11 mouse monoclonal antibodies. among the 121 combinations tested, 2 were selected for their sensitivity and specificity. both were applied to plasmas of (a) acute patients, (b) peo ... | 1990 | 2202221 |
| plasmodium falciparum infection rates in anopheles gambiae, an. arabiensis, and an. funestus in western kenya. | mosquitoes collected monthly for 1 year from human habitations in the kisumu area of western kenya were identified by morphological characters as anopheles gambiae giles sensu lato (an. gambiae s.l.) or an. funestus. of the mosquitoes collected, 7,244 (67%) of the an. gambiae s.l. and 8,511 (87%) of the an. funestus were tested by enzyme-linked immunosorbent assay (elisa) for the presence of plasmodium falciparum circumsporozoite (cs) protein. elisa positivity rates were 8.2% for an. gambiae s.l ... | 1990 | 2202222 |
| renal pathology in owl monkeys in plasmodium falciparum vaccine trials. | renal specimens of 16 owl monkeys (aotus vociferans) were studied by light microscopy and immunohistochemistry during a vaccine trial with recombinant proteins of the ring-infected erythrocyte surface antigen (resa) of plasmodium falciparum. deposition of igg, c3, and p. falciparum antigens in the mesangium was demonstrated by the peroxidase anti-peroxidase (pap) method. a relationship between the severity of parasitemia at the time of death and the presence of nephropathy was not apparent. | 1990 | 2202223 |
| surface molecules on plasmodium falciparum-infected erythrocytes involved in adherence. | the identity of cell surface receptor molecules on plasmodium falciparum-infected erythrocytes is of great interest since the functional sites involved in attachment to endothelial cells may be structurally conserved in wild isolates. such conserved sites may represent suitable antigenic targets for a vaccine-induced immune response that would block or reverse infected cell sequestration in vivo. identification of the infected cell receptor sites may also lead to novel methods for treatment of a ... | 1990 | 2202225 |
| in vitro and ex-vivo models of sequestration in plasmodium falciparum infection. | sequestration is the process by which erythrocytes infected with the mature forms of the malarial parasite plasmodium falciparum disappear from circulation and accumulate within venules and capillaries of various organs and tissues. several laboratory models of this phenomena are briefly described with a discussion of their values and shortcomings. | 1990 | 2202226 |
| the pathology of human cerebral malaria. | blockage of the cerebral microvasculature by plasmodium falciparum-infected erythrocytes appears to be the principal cause of human cerebral malaria. knobs which appear on the membrane of the infected erythrocytes adhere to the endothelium, causing the obstruction of cerebral microvessels. protein molecules such as cd36, thrombospondin, and intercellular adhesion molecule-1, which are present on the membrane of endothelial cells, may act as receptors for the attachment of knobs of p. falciparum- ... | 1990 | 2202227 |
| cerebral malaria in children: clinical implications of cytoadherence. | in endemic areas, most of the people who die from falciparum malaria are young children. death is commonly preceded by coma (cerebral malaria). the possible role of cytoadherence in this clinical picture is considered. | 1990 | 2202228 |
| efficacies of chloroquine and pyrimethamine-sulphadoxine in a nigerian population with chloroquine resistant p. falciparum malaria. | a modification of the standard world health organisation 7--day in vivo test was used to assess the parasitologic and, to limited extent, the clinical response of children less than 5 years of age to defined oral dosages of chloroquine and pyrimethamine-sulphadoxine during the 14 days following the initiation of treatment. the study took place in jato-aka, a rural community in benue state of nigeria. 471 children were screened and 271 (59%) of these had plasmodium parasites thus showing a high t ... | 1990 | 2202586 |
| the in vitro response of plasmodium falciparum to amodiaquine, quinine and quinidine in tanga region, tanzania. | the in vitro response of p. falciparum to amodiaquine, quinine and quinidine was assessed in tanga region where chloroquine resistance is established, to determine baseline susceptibility levels which could guide health care deliverers on the suitability of these drugs for the treatment of falciparum malaria in the areas studied. amodiaquine resistance was observed in all of the three areas. 16.7%, 24.0% and 14.7% of successful in vitro tests showed resistance to amodiaquine in korogwe, muheza a ... | 1990 | 2202587 |
| effect of polyamines on the activity of malarial alpha-like dna polymerase. | dna polymerase from the malarial parasite plasmodium falciparum required mg2+ for activity, putrescine (1 mm) caused a twofold increase in enzyme activity in the presence of a suboptimal concentration of mgcl2 (2 mm). spermidine (1.5-2.0 mm) or spermine (0.1-0.3 mm) increased the activity of malarial dna polymerase, in the presence of 2 mm mgcl2, by factors of 6 and 3-5, respectively. the activity of dna polymerase from calf thymus or from nih 3t3 cells transformed by the ras oncogene were not s ... | 1990 | 2202598 |
| control of actin filament length by phosphorylation of fragmin-actin complex. | fragmin is a ca2(+)-sensitive f-actin-severing protein purified from a slime mold, physarum polycephalum (hasegawa, t., s. takahashi, h. hayashi, and s. hatano. 1980. biochemistry. 19:2677-2683). it binds to g-actin to form a 1:1 fragmin/actin complex in the presence of micromolar free ca2+. the complex nucleates actin polymerization and caps the barbed end of the short f-actin (sugino, h., and s. hatano. 1982. cell motil. 2:457-470). subsequent removal of ca2+, however, hardly dissociates the c ... | 1990 | 2202733 |
| antimalarial activity of new water-soluble dihydroartemisinin derivatives. 3. aromatic amine analogues. | a series of artemisinin (1) derivatives containing bromo and heterocyclic or aromatic amine functions was prepared in the search for analogues with good water solubility and high antimalarial activity. treatment of dihydroartemisinin (2a) with boron trifluoride etherate at room temperature gave the key intermediate, 9,10-dehydrodihydroartemisinin (3), which, on reaction with bromine, gave the dibromide 4. the latter was condensed with amines in anhydrous ch2cl2 at less than -10 degrees c to give ... | 1990 | 2202831 |
| isolated malaria outbreak in somalia: role of chloroquine-resistant plasmodium falciparum demonstrated in balcad epidemic. | a study was conducted in balcad in december 1988 during a reported outbreak of malaria in order to investigate possible factors contributing to the outbreak. the slide positivity rate of 71% among fever patients, which was significantly higher than the usual rate, suggests the existence of a fresh malaria outbreak in the area. high parasite densities together with the pronounced malaria symptoms among both resident children and adult immigrants indicated little, if any, malaria experience in the ... | 1990 | 2202841 |
| processing and microfiltration of mosquitoes for malaria antigen detection in a rapid dot immunobinding assay. | data on a technique for the detection of antigen from arthropod vectors in a dot immunobinding assay are presented. in this system, antigen present in the vector was first solubilized in sodium dodecyl sulfate. the homogenate from this process was microfiltered through a two-membrane sandwich; target antigen molecules passed through the first membrane and were immobilized on the second one. the first membrane was nonbinding and served to impinge debris. the second membrane was a high-protein-bin ... | 1990 | 2203808 |
| erythrocyte sequestration and anemia in severe falciparum malaria. analysis of acute changes in venous hematocrit using a simple mathematical model. | microvascular erythrocyte sequestration, the characteristic pathological feature of falciparum malaria, was evaluated using a mathematical model in 46 patients with severe infections. from admission radioisotopic circulating red cell volumes and simultaneous venous hematocrits, the model-derived sequestrum hematocrit (mean [95% confidence limits]: 0.70 [0.43-0.97], n = 29) was twice that of peripheral blood (0.33 [0.30-0.36]). serial reticulocyte and radiolabeled erythrocyte counts indicated tha ... | 1990 | 2203822 |
| malaria parasitization and hormonal imbalance in virgin mice. | the effect of the malaria parasite plasmodium berghei berghei on the estrus cycle was studied in rodents. it was observed that there was a delay at the proestrus phase of the estrus cycle. endocrinological evidence for lack of ovulation at estrus during infection was presented. although there was an elevation in the level of immune complexes and white blood cell counts, the red blood cell counts decreased as infection progressed. anal temperature recordings showed pyrexia. there was a wide diffe ... | 1990 | 2203871 |
| chloroquine-resistant plasmodium falciparum malaria in the kavango region of namibia. | the sensitivity to chloroquine of plasmodium falciparum from the kavango region of namibia was determined by a 24-hour test in vitro. twenty-six isolates were successfully tested, of which 11 were resistant to a low degree, schizogony being inhibited at 8 pmol/well. the results of the dill-glazko test for the presence of 4-aminoquinolines in urine indicate that chloroquine is not widely used in the area. | 1990 | 2204121 |
| cell-mediated immune responses to soluble plasmodium falciparum antigens in residents from an area of unstable malaria transmission in the sudan. | this paper describes immune responses to p. falciparum infection in individuals living in an area of highly seasonal, unstable malaria transmission. the in vitro cellular immune responses of peripheral blood mononuclear cells (pbmc) from 36 sudanese donors to a complex of affinity purified soluble p. falciparum antigens (spag) and two components thereof (ag1 and ag7) were examined and compared to humoral immune parameters. in 29/36 sudanese donors, spag induced a significant lymphoproliferative ... | 1990 | 2204363 |
| cytochrome p-450 activity in malarial parasites and its possible relationship to chloroquine resistance. | cytochrome p-450-dependent enzyme activities have been determined in malarial parasites. both plasmodium berghei and plasmodium falciparum parasites exhibited activity and these activities were greater in chloroquine resistant parasites than in sensitive strains. this enzyme activity could be induced by phenobarbitone and inhibited by specific inhibitors of the cytochrome p-450 family of enzymes. the significance of these observations in parasite drug resistance is discussed. | 1990 | 2204831 |
| expression, purification, biochemical characterization and inhibition of recombinant plasmodium falciparum aldolase. | the energy metabolism of the blood stage form of the human malaria parasite plasmodium falciparum is adapted to the host cell. like erythrocytes, p. falciparum merozoites lack a functional citric acid cycle. generation of atp depends therefore fully on the glycolytic pathway. aldolase is a key enzyme of this pathway and a high degree of sequence diversity between parasite and host makes it a potential drug target. we have expressed the enzyme in its tetrameric form in escherichia coli and the ca ... | 1990 | 2204832 |
| regions of an eimeria tenella antigen contain sequences which are conserved in circumsporozoite proteins from plasmodium spp. and which are related to the thrombospondin gene family. | coccidiosis, caused by eimeria spp., is a major disease of economic importance to the poultry industry. the cloning and characterisation of genes coding for antigens of those species infecting chickens is an initial step in the identification of protective antigens suitable for the development of a genetically engineered vaccine. this report describes the molecular characterisation of an antigen of e. tenella produced by the recombinant lambda amp3 bacteriophage ethl6. three native polypeptides ... | 1990 | 2204833 |
| the gene for hypoxanthine phosphoribosyl transferase of plasmodium falciparum complements a bacterial hpt mutation. | the enzyme hypoxanthine phosphoribosyl transferase of plasmodium falciparum has been overexpressed in escherichia coli. the protein was found to be active enzymatically. when the recombinant expression vector (ppfprt2) was transformed and expressed in a salmonella typhimurium mutant kp1684 (pure deod hpt gpt), the active expressed protein complemented the hpt mutation in the bacteria. we discuss the practical value of this strain. assays of the expressed protein in the mutant extract showed that ... | 1990 | 2204834 |
| sequence conservation of a functional domain of erythrocyte binding antigen 175 in plasmodium falciparum. | | 1990 | 2204835 |
| [malaria vaccines, a necessity for future control of malaria. status and future perspectives]. | traditional malaria control is in a crisis on account of chemo-resistance of plasmodium falciparum and insecticide-resistance of the malaria mosquito. new ways to control malaria have been opened by the possibility of producing a vaccine. several malaria proteins (e.g. csp, gp195, pf155/resa, glurp) have been sequenced and it has been shown that most of the proteins have repetitive units. analyses of t- and b-cell epitopes show that t-cell epitopes are mainly localized to the non-conserved parts ... | 1990 | 2205029 |
| influence of malaria infection on peroxyl-radical trapping capacity in plasma from rural and urban thai adults. | measurement of peroxyl-radical trapping capacity (trap) were made in plasma from patients with malaria from a rural and an urban thai community. the results were compared with those from control subjects living in the same areas and chosen to match the patients closely. measurements were also made of various antioxidants including nutritional indices vitamin c and alpha-tocopherol and the non-nutritional indices urate and protein-sulphydryl. parasite counts, temperature on examination and the du ... | 1990 | 2205293 |
| stage-dependent effect of deferoxamine on growth of plasmodium falciparum in vitro. | deferoxamine (df) has antimalarial activity that can be demonstrated in vitro and in vivo. this study is designed to examine the speed of onset and stage dependency of growth inhibition by df and to determine whether its antimalarial activity is cytostatic or cytocidal. growth inhibition was assessed by suppression of hypoxanthine incorporation and differences in morphologic appearance between treated and control parasites. using synchronized in vitro cultures of plasmodium falciparum, growth in ... | 1990 | 2205310 |
| genetic diversity in the major merozoite surface antigen of plasmodium falciparum: high prevalence of a third polymorphic form detected in strains derived from malaria patients. | we studied the diversity of the polymorphic 195-kda antigen (p190) of plasmodium from infected individuals. genomic parasite dna was extracted from the blood of 30 donors from different endemic areas of brazil. the 5' region, encoding the polymorphic n-terminal part of p190 was analysed following polymerase chain reaction (pcr). multiple infections of genetically distinct parasites could be detected within infected malaria patients. sequence analysis and oligodeoxyribonucleotide typing of the pc ... | 1990 | 2205540 |
| cloning and expression in escherichia coli of a hypoxanthine-guanine phosphoribosyltransferase-encoding cdna from plasmodium falciparum. | the enzyme hypoxanthine-guanine phosphoribosyltransferase (hgprt) of plasmodium falciparum plays a key role in the salvage of preformed purine nucleotides from parasite-infected erythrocytes. since p. falciparum cannot synthesize purines de novo, development of inhibitors specific for the parasite hgprt should be an effective method of chemotherapy. to provide sufficient amounts of hgprt for biochemical and crystallographic analysis, we have isolated the p. falciparum hprt cdna sequence and expr ... | 1990 | 2205541 |
| [clinical evaluation of antimalarial drugs]. | we have analyzed the clinical data of 189 patients with malaria to establish antimalarial regimens in japan. the causative parasite species were plasmodium falciparum in 56 cases (30%), p. vivax in 132 (70%) and p. malariae in 1 (1%). the outcomes f malaria cases are as follows: cure rats in falciparum and vivax malaria are 86% and 91%, respectively. two patients died of falciparum malaria and recurrence occurred in 6 cases (11%) of falciparum malaria. relapse was seen in 12 (9%) of vivax malari ... | 1990 | 2205671 |
| growth of plasmodium falciparum in human erythrocytes containing abnormal membrane proteins. | to evaluate the role of erythrocyte (rbc) membrane proteins in the invasion and maturation of plasmodium falciparum, we have studied, in culture, abnormal rbcs containing quantitative or qualitative membrane protein defects. these defects included hereditary spherocytosis (hs) due to decreases in the content of spectrin [hs(sp+)], hereditary elliptocytosis (he) due to protein 4.1 deficiency [he(4.1(0))], he due to a spectrin alpha i domain structural variant that results in increased content of ... | 1990 | 2205856 |
| in vitro sensitivity of multiresistant plasmodium falciparum to new candidate antimalarial drugs in western thailand. | the present study, carried out in 1987 in thailand, has been designed to validate the in vitro microtest system, standardized by the world health organization (who), for the new antimalarials pyronaridine and halofantrine. the sensitivity of naturally acquired, multiresistant populations of plasmodium falciparum has been assessed in order to develop a data base for further longitudinal investigations. for both drugs the in vitro microtest system seems to be suitable. the concentration range of p ... | 1990 | 2205926 |
| new developments in malaria diagnostic techniques. | | 1990 | 2205927 |
| [combined action of pyronaridine and sulfadoxine/pyrimethamine against plasmodium berghei anka strain in mice]. | pyronaridine, a highly effective antimalarial drug, was synthesized and developed by this institute. in order to test whether the joint blood schizontocidal action of pyronaridine (pnd) and 2:1 mixture of sulfadoxine/pyrimethamine (sp) resulted in a potentiation or an additive effect, groups of p berghei anka strain-infected mice were treated with various single oral doses of pnd and sp. thin blood smears were made after 72 h and the parasitemia-negative rates were calculated. the ed50 values ob ... | 1990 | 2206014 |
| multiple-dose pharmacokinetics and in vitro antimalarial activity of dapsone plus pyrimethamine (maloprim) in man. | 1. the multiple-dose kinetics of dapsone (dds), its major metabolite monoacetyldapsone (madds) and pyrimethamine (pyr) were studied in six healthy adult male volunteers following weekly administration of maloprim (100 mg dds plus 12.5 mg pyr). 2. after the last maintenance dose of maloprim, the following kinetic parameters (mean values) were determined for dds and pyr, respectively: maximum plasma concentration (cmax) = 1,134 and 116 ng ml-1; elimination half-life (t1/2) = 23 and 105 h; plasma c ... | 1990 | 2206787 |
| comparison of chloroquine, pyrimethamine and sulfadoxine, and chlorproguanil and dapsone as treatment for falciparum malaria in pregnant and non-pregnant women, kakamega district, kenya. | to compare treatment and protection against falciparum malaria in pregnant and non-pregnant women with three drug regimens. | 1990 | 2207399 |
| [epidemiology of malaria in french guiana]. | a malaria investigation in the 1970-1986 period in french guiana shows an increased plasmodium index (4.6%) when compared with the data of the 1970-1979 decade (2.7%), an incidence rate of 8.6 per 1,000 inhabitants (against 6.4 previously) and always a high frequency of p. falciparum (85%). the principal vector, a. darlingi, still remains sensitive to ddt but the authors recommend an updating of the anti-vectorial program control. a longitudinal serologic survey, on the school children during tw ... | 1990 | 2208450 |
| [plasmodium falciparum drug resistance in the congo. evaluation of surveys carried out from 1985 to 1989]. | surveys on drug sensitivity of plasmodium falciparum carried out between 1985 and 1989 included 7-day in vitro tests and in vivo tests. 485 in vivo tests were carried out in eight surveys conducted in brazzaville and in several inland regions. the subjects were congolese children aged between 3 months and 15 years old. they were recruited in hospital, mother-child clinics or at school. the drugs studied were chloroquine, amodiaquine and the sulfadoxine-pyrimethamine combination. 182 strains were ... | 1990 | 2208453 |
| [development of chemoresistance of plasmodium falciparum to chloroquine and mefloquine in benin between 1980 and 1989]. | resistance of p. falciparum to chloroquine has been notified in 1986 in non-immune visitors. authors organized surveys of in vivo and in vitro tests to follow evolution of the phenomena. the increase in number of p. falciparum strains resistant to chloroquine was sudden in 1986 but stopped to rise from this date, and even seemed to decrease gently. the geographical distribution of the resistance, restricted to the region of cotonou, could be explained by illegitimate chloroquine distribution. bu ... | 1990 | 2208463 |
| [ecological factors in the renewed outbreak of malaria in madagascar]. | the new epidemic of malaria which spread on the madagascar high plateau in 1986-1987 is due to the combination of several factors (some of which are analysed by the authors, especially those related to anopheles, parasite and man). the authors compare the situations on the high plateau and on st mary island, on the east madagascar coast, where the malaria is stable. concerning the vector, the most interesting fact is the come-back of anopheles funestus on the high plateau from which it had disap ... | 1990 | 2208464 |
| [soluble protein and esterase isozyme analysis of adult female anopheles stephensi after plasmodium yoelii yoelii-infected blood meal]. | in this paper, the system of anopheles stephensi and plasmodium yoelii yoelii was used as animal model. the soluble protein and esterase isozymes of adult female mosquitoes at various times after taking noninfected and plasmodia-infected blood meal were investigated. the result shows that the amount of soluble protein in plasmodia-infected mosquitoes was lower than that in noninfected ones (p less than 0.01); the activity and electrophoretic patterns of est in infected mosquitoes being also diff ... | 1990 | 2208623 |
| [in vitro cultivation and scanning electron microscopic observation of plasmodium berghei]. | to compare the effects of sera on the growth of plasmodium berghei, the erythrocytic stages were cultured with rat serum, human umbilical cord serum, human b-type serum, rabbit serum, calf serum and calf serum with hypoxanthine respectively. the topography of the erythrocyte and parasite cultured with calf serum were observed before and 12, 20 and 28 hours after cultivation. all of the sera used did not effectively improve the long-term culture of p. berghei, regardless of some differences in sh ... | 1990 | 2208625 |
| [preliminary study on the surface antigen gene of plasmodium malariae]. | the genomic hind iii lambda gt1149 library from plasmodium malariae was screened with two types of oligonucleotides, both of which were from the p190 gene of p. falciparum. one, mad20 type, was made from spanning nucleotides 4488-4562 in the p190 gene of mad20 strain and another, k1 type, was made from spanning nucleotides 3652-3692 in the p190 of k1 strain. both were end-labelled with 32p-atp as probes before hybridization. two clones were selected. one clone, designated lambda msa-1, was speci ... | 1990 | 2208630 |
| clinical pharmacokinetics of mefloquine. | mefloquine, a quinoline-methanol antimalarial, is effective single dose therapy for all species of malaria infecting humans, including multi-drug-resistant plasmodium falciparum. it is used both in prophylaxis and treatment. mefloquine is available either as the hydrochloride salt alone, or in a combined preparation with sulfadoxine and pyrimethamine. there is no parenteral formulation. several assay methodologies have been developed, but high performance liquid chromatography has been the most ... | 1990 | 2208897 |
| primary structure of profilins from two species of echinoidea and physarum polycephalum. | profilin is a small g-actin-binding protein, the amino acid sequence of which was previously reported for calf, human, acanthamoeba and yeast. here the amino acid sequences of three profilins obtained from eggs of two species of echinoidea, clypeaster japonicus (order, clypeasteroida) and anthocidaris crassispina (order, echinoida), and plasmodium of physarum polycephalum were determined. two echinoid profilins were composed of 139 amino acid residues, n-termini were acylated and the molecular m ... | 1990 | 2209623 |
| structural diversity of plasmodium falciparum gp200 is detected by t cells. | t lymphocyte clones (tlc) specific for p. falciparum gp200 (a glycoprotein precursor of the main merozoite surface component) were obtained from two individuals with past exposure to malaria. the 25 established tlc carried the cd4 antigen and proliferated in the presence of immunopurified gp200, crude lysate of the parasite and intact infected red blood cells. they were further tested in proliferation assays for their capacity to recognize the structural diversity displayed by gp200. the stimula ... | 1990 | 2209687 |
| plasmodium cynomolgi: serum-mediated blocking and enhancement of infectivity to mosquitoes during infections in the natural host, macaca sinica. | the infectivity of plasmodium cynomolgi in its natural host, the toque monkey, macaca sinica, to anopheles tessellatus mosquitoes was studied in relation to the evolution of anti-sexual-stage immunity in the host during the course of a blood-induced infection. the effects of serum on the infectivity of gametocytes and the intrinsic infectivity of gametocytes to mosquitoes on each day were assessed in membrane feeding experiments. mosquitoes were also directly fed on the animal on each day. our r ... | 1990 | 2209788 |
| plasmodium falciparum: differential parasite reactivity of rabbit antibodies to repeated sequences in the antigen pf155/resa. | for selection of immunogens capable of inducing high levels of antibodies reactive with the plasmodium falciparum antigen pf155/resa, rabbits were immunized with synthetic peptides corresponding to sequences based on the repeat subunits eenvehda and (eenv)2 from the c-terminus of this antigen. the antibodies obtained were analyzed with regard to binding to synthetic peptides in elisa and to reactivity with parasite antigens by immunofluorescence or immunoblotting. all antisera reacted with both ... | 1990 | 2209789 |
| pf155/resa antigen is localized in dense granules of plasmodium falciparum merozoites. | immunoelectron microscopy demonstrated the presence of pf155/resa in dense granules of plasmodium falciparum merozoites rather than in micronemes as previously suggested. since the dense granules are released after the merozoite enters the parasitophorous vacuole, the role of pf155/resa in invasion and subsequent steps of parasite development may differ from that of a molecule located in the micronemes. | 1990 | 2209790 |
| plasmodium falciparum: a rapid assay for cytoadherence of [3h]hypoxanthine-labeled infected erythrocytes to human melanoma cells. | | 1990 | 2209792 |
| status of plasmodium falciparum resistance to chloroquine in gujarat, rajasthan and maharashtra states of india. | an extended study from 1978-88 revealed that in the western states of india i.e., rajasthan, gujarat and maharashtra; p. falciparum resistance to chloroquine has a scattered pattern in its distribution. however in gujarat, r-iii level of resistance is established in southern districts showing four fold increase from 1.79% in 1985 to 8.2% in 1988. in this area use of some alternate drug is indicated. | 1990 | 2209926 |
| active malaria transmission in south mizoram. | anopheles dirus was incriminated as malaria vector with 1.12% sporozoite rate in tlabong (demagiri) subdivision, mizoram. high parity rate of a. dirus (33.69%) and a. minimus (52.87%) further confirmed their vectorial status. both the vectors were found highly susceptible to 4% ddt. | 1990 | 2209927 |
| fine structure of the erythrocytic stages of plasmodium vivax and the host cell alterations. | fine structural analysis of the trophic and sexual stages of plasmodium vivax obtained from naturally infected humans revealed that in general, the structural features as well as certain specialized functions such as haemoglobin ingestion and utilization etc., are similar to those described for other malaria parasites. young trophozoite is characterised by less condense cytoplasm with scattering of free ribosomes and minimum amount of endoplasmic reticulum. the trophozoite grows by feeding on th ... | 1990 | 2209930 |
| chloroquine sensitivity of plasmodium falciparum in shankargarh block of allahabad district (u.p.). | chloroquine sensitivity of plasmodium falciparum was carried out in shankargarh block of allahabad district, u.p. to confirm the presence of resistant strain in the area. a total of 47 cases were subjected to in vivo extended test, of which resistance was detected in 11 cases at r-ii/r-iii level and in 9 cases at r-i level. one case out of 18 subjected to standard 7-day in vivo test showed resistance at r-iii level. micro in vitro test was done for 24 cases, of which growth was seen in 21 contro ... | 1990 | 2209931 |
| quartan malaria--an investigation on the incidence of plasmodium malariae in bisra phc, district sundargarh, orissa. | a longitudinal study on the incidence of p. malariae was taken up from september 1988 to december 1989 in bisra block, district sundargarh, orissa covering 38,615 population, which is mainly tribal. the area is a known hard-core malarious region in the garhjat hill range in eastern india. in this study, out of 22,217 blood smears examined through weekly active surveillance, 7362 (33.1%) were found malaria parasite positive. out of the total positive cases, 82 (1.1%) were p. malariae. these occur ... | 1990 | 2209932 |