| duration of immunity following a single vaccination with irradiated sporozoites of plasmodium berghei. | a rodent model of sporozoite immunization against malaria based on a single immunizing dose is described. the duration of protective immunity was measured as a function of dose, and the results suggest that the percentage of protection follows a bimodal distribution. the first peak occurs between days 7-12 after immunization, while the second peak occurs at approximately 28 days. although the percentage of protection declines steadily after the second peak, some immunity was detectable as long a ... | 1979 | 120765 |
| preliminary studies on vaccination of rhesus monkeys with irradiated sporozoites of plasmodium knowlesi and characterization of surface antigens of these parasites. | studies were conducted to develop an effective method of inducing protection against sporozoite-induced malaria in a primate system and to obtain information regarding the surface membrane antigens of sporozoites. immunization of rhesus monkeys was performed with gamma-irradiated sporozoites of plasmodium knowlesi. levels of antisporozoite antibodies were monitored by immunofluorescence, sporozoite neutralization, and the circumsporozoite precipitate reaction, and appeared to correlate well with ... | 1979 | 120766 |
| factors affecting the in vitro culture of plasmodium falciparum and plasmodium knowlesi. | plasmodium falciparum and plasmodium knowlesi have been established in continuous culture using the basic method of trager & jensen. various parameters of the culture system have been examined, namely, the gas requirements, serum and red cell requirements, frequency of medium replacement, and a comparison of static and agitated cultures made. the most important factors affecting growth in vitro seem to be the oxygen tension, red cell concentration, the frequency with which old medium is replaced ... | 1979 | 120767 |
| immunization of experimental monkeys against plasmodium falciparum: use of synthetic adjuvants. | the replacement of freund's adjuvant by a possible safe adjuvant for effective immunization of owl monkeys (aotus trivirgatus griseimembra) against a human malaria parasite, plasmodium falciparum, has been investigated. experiments involved the use of two synthetic adjuvants: mdp (n-acetylmuramyl-l-alanyl-d-isoglutamine) and stearoyl-mdp (6-o-stearoyl-n-acetylmuramyl-l-alanyl-d-isoglutamine). in both cases, p. falciparum merozoites obtained through short-term in vitro cultivation were used as an ... | 1979 | 120768 |
| malaria vaccination with irradiated sporozoites: serological evaluation of the antigen and antibody responses. | vaccination against plasmodium falciparum with attenuated sporozoites is the goal of the us navy's malaria vaccine program. one requirement in the development of this vaccine is an immunological test to study the sporozoite antigen and immune responses it induces. using an indirect fluorescent antibody test (ifat) and p. berghei in the mouse or rat as a model, we have made significant progress toward this goal. four antigens were detected in vaccine preparations: sporozoite-specific antigens, mo ... | 1979 | 120769 |
| characterization of sporozoite surface antigens by indirect immunofluorescence: detection of stage- and species-specific antimalarial antibodies. | indirect immunofluorescence (if) was used to localize stage-specific antigen(s) on the surface of the sporozoite membrane. the authors examined the feasibility of using an if assay to determine whether an antisporozoite response is developed by individuals living in endemic areas. the specificity and sensitivity of the if assay were first defined by using hyperimmune sera of sporozoite-immunized hosts protected against rodent (p. berghei), simian (p. knowlesi), and human (p. falciparum, p. vivax ... | 1979 | 120770 |
| in vitro inhibition of the growth of plasmodium falciparum by aotus serum. | an in vitro assay for measuring growth and reinvasion inhibition of plasmodium falciparum was developed from a microculture system. inhibition of growth was observed after parasites had been incubated with aotus serum obtained from monkeys that had become immune to malaria after repeated exposure to p. falciparum. immune aotus serum (ias), at concentrations as low as 1.25%, showed a marked inhibitory effect upon parasites cultured in 10% normal human serum (nhs). growth was also inhibited when 5 ... | 1979 | 120771 |
| a study of cellular and humoral immune responses in owl monkeys (aotus trivirgatus) following vaccination against plasmodium falciparum. | vaccination of animals against malaria parasites is thought to induce two basic immunological responses: (i) specific recognition of parasite antigens by the host, and (ii) a generalized immune enhancement due to the presence of adjuvant. immunological techniques were used in this study to monitor cellular and humoral immune changes in owl monkeys prior to and following immunization with a vaccine consisting of merozoite-enriched schizonts of plasmodium falciparum and one of three adjuvants: n-a ... | 1979 | 120772 |
| use of attenuated sporozoites in the immunization of human volunteers against falciparum malaria. | three human volunteers were successfully protected against sporozoite challenge by immunization with attenuated sporozoites of the tamenie strain of plasmodium falciparum from ethiopia. the immunizing sporozoites were attenuated by exposing infected anopheles stephensi mosquitos to x-rays at a dose of at least 120 gy (12 000 rad). these irradiated, infected mosquitos were allowed to feed upon volunteers, thereby inoculating sporozoites into their blood stream. during the 10- to 38-week period of ... | 1979 | 120773 |
| isolation of stages of the human parasite plasmodium falciparum from culture and from animal blood. | procedures for isolation of various forms of the asexual erythrocytic stages of the human parasite plasmodium falciparum are outlined. the procedures employ the plasma expander physiogel, which is composed of a chemically modified, partially hydrolysed gelatin dissolved in ringer's lactate. based on the observation that parasitized cells which are easily separable by this technique differ appreciably at the ultrastructural level, a mechanism by which separation occurs is proposed. | 1979 | 120774 |
| the use of membrane screen filters in the isolation of plasmodium berghei sporozoites from mosquitos. | an improved procedure is presented for the isolation of plasmodium berghei sporozoites from host mosquitos. the method employs filtration through a series of nuclepore membranes followed by two consecutive centrifugations of the filtrate layered over renografin-60 solutions of different densities. a coulter counter was used to compare isolations prepared by this technique with those prepared by a routinely employed discontinuous gradient method. when the sporozoite concentration in each preparat ... | 1979 | 120775 |
| low-temperature preservation of sporozoites of plasmodium berghei. | large numbers of biologically active sporozoites are needed as a source of potential antigen in the development of a malaria vaccine and the most practical method of accumulating sufficient numbers of these forms would be to freeze and store them at low temperature. the purpose of this work was to determine the feasibility of preserving the infectivity of frozen and thawed sporozoites. the results indicate that sporozoites of plasmodium berghei exhibit a typical response to freezing over a wide ... | 1979 | 120776 |
| localization and chemical characterization of plasmodium knowlesi schizont antigens. | the identification of malarial antigens that induce protective immunity could provide a rational basis for developing an effective antimalarial vaccine as well as specific serodiagnostic tests indicative of clinical immune status. since protective immunity is probably induced by stage-dependent rather than stage-independent antigens, the antigenic composition of different stages of plasmodium knowlesi has been compared, and a limited chemical characterization undertaken. this information should ... | 1979 | 120777 |
| particulate beta 1-3 glucan and casual prophylaxis of mouse malaria (plasmodium berghei). | | 1979 | 121199 |
| blood schizontocidal activity of some antibiotics against plasmodium knowlesi infection in assamese monkey. | | 1979 | 121297 |
| chemotherapeutic studies with mefloquine and selection of a mefloquine resistant strain of plasmodium berghei. | | 1979 | 121298 |
| parasitic infections and the genitourinary tract. | | 1975 | 124862 |
| pathogenesis of acute avian malaria. iii. antigen and antibody complexes as a mediator of anemia in acute plasmodium gallinaceum infections of chickens. | in a study of antigens and antibodies found in malarious chicken blood, antigen activity was found in plasma, and in hypertonic saline eluates of blood cells. a soluble antigen was extracted from parasites liberated from erythrocytes. two classes of antigen were differentiated, one a globulin associated "serum antigen" which was found to show identity with a serum antigen from blood of rats with acute babesia rodhaini infection, and another that was associated with the plasmodium gallinaceum par ... | 1975 | 125550 |
| [chemotherapy in areas of persistent malaria transmission and resistence of plasmodium falciparum to chloroquine in panama]. | | 1975 | 125597 |
| [introduction of malaria into the rsfsr]. | | 1975 | 126355 |
| chloroquine-resistant malaria in burma. | two field trials to detect chloroquine-resistant malaria were conducted according to who recommendations in a malaria free area near rangoon. peripheral blood smears were examined for asexual forms of p. falciparum on day one through to day seven, on day 14, 21, and 28 after a standard dose of 1500 mg. of chloroquine base. haskins test to detect chloroquine in urine was done on all cases and plasma chloroquine levels were measured in some. out of 105 patients tested ri resistance was detected in ... | 1975 | 128638 |
| [strategy for worldwide eradication of malaria]. | | 1976 | 129142 |
| [gel diffusion tests in malaria. validity according to different techniques of extracting soluble antigens. sensitivity compared with indirect immunofluorescence]. | the value of the gel diffusion test in human malaria varied considerably, depending on the different methods tested to obtain soluble antigens. with one of these antigens, a saponin lysate of plasmodium falciparum infected erythrocytes, the test proved as sensitive and specific as the ifa test with the homologous antigen. | 1975 | 129243 |
| the kidney in infectious diseases. | | 1976 | 129758 |
| [world-wide studies on malaria]. | | 1976 | 130141 |
| ca2+-sensitivity of actomyosin atpase purified from physarum polycephalum. | a contractile protein closely resembling natural actomyosin (myosin b) of rabbit skeletal muscle was extracted from plasmodia of the slime mold, physarum polycephalum, by protecting the sh-groups with beta-mercaptoethanol or dithiothreitol. superprecipitation of the protein induced by mg2+-atp at low ionic strength was observed only in the presence of very low concentrations of free ca2+ ions, and the mg2+-atpase [ec 3.6.1.3] reaction was activated 2- to 6-fold by 1 mum of free ca2+ ions. crude ... | 1975 | 131790 |
| physarum tropomyosin-troponin complex. isolation and properties. | the relaxing protein (tm-tn complex) was isolated from plasmodia of physarum. sds-gel electrophoresis revealed that the relaxing protein consists of tropomyosin subunits with a molecular weight of 35,000 troponin subunits with molecular weights of 38,000 (t) and 24,000 (i) and several other components. no component corresponding to muscle troponinc (mw-18,000) was detected in the plasmodium relaxing protein. the relaxing protein combined with muscle f-actin, and inhibited the atpase [ec 3.6.1.3] ... | 1975 | 131791 |
| clinical and experimental investigation of immune complexes in malaria. | | 1976 | 133011 |
| a calcium-sensitive preparation from physarum polycephalum. | differential ultracentrifugation of an extract of the plasmodium of physarum polycephalum yields a high-speed fraction which exhibits calcium-sensitive adenosine triphosphate activity at low ionic strength. the rate of inorganic phosphate production increased from 2- to 25-fold in different preparations when the calcium concentration was increased from about 10(-8) to 10(-5) m. complement fixation using specific antibody to physarum myosin showed the fraction to contain 3% myosin. by electron mi ... | 1976 | 134744 |
| [attempt to obtain in vitro pre-erythrocyte forms of plasmodium vivax in human liver cell cultures inoculated with sporozoites]. | using sporozoites of a strain of plasmodium vivax of north korean origin maintained in human subjects and in anopheles atroparvus, the authors inoculated human liver cell cultures (primary cultures and ist subcultures). the appearance of some rare intracytoplasmic forms is described, which are thought to be very likely connected with the pre-erythrocytic cycle of p. vivax. further attempts are nevertheless necessary to confirm, or invalidate, the obtained results. | 1976 | 135630 |
| [renal involvement in malaria (author's transl)]. | malaria infection leads to renal involvement. reversible proteinuria accompanies many plasmodial infections. chronic malarial nephrotic syndrome is specifically associated with quartan malaria. acute renal failure is restricted to infections with plasmodium falciparum. the pathogenesis of renal involvement during malarial infections includes immunological mechanisms. it is now realized that there exist at least two types of immunological processes: acute transient immune-complex glomerulonephrit ... | 1976 | 135874 |
| immunity to plasmodium berghei yoelii in mice. i. the course of infection in t cell and b cell deficient mice. | the course of infection with 17x nonlethal plasmodium berghei yoelii was examined in balb/c mice which were deficient in either t cells or b cells. markedly increased parasitemia and mortality were observed in athymic (nude) mice which had been backcrossed on a balb/c background (t cell deficient) compared to similar mice which had been grafted with neonatal balb/c thymus, and were also observed in balb/c mice suppressed from birth with goat antiserum to mouse mu-chain (b cell deficient) compare ... | 1976 | 136472 |
| antifolate studies. activities of 40 potential antimalarial compounds against sensitive and chlorguanide triazine resistant strains of folate-requiring bacteria and escherichia coli. | as part of the search for new antimalarial drugs, a screening program was developed using sensitive and chlorguanide triazine (cgt, cycloguanil) resistant strains of the folate-requiring bacteria, streptococcus faecium durans, lactobacillus casei, and pediococcus cerevisiae. the activities of 40 compounds have been studied against these strains and escherichia coli. observations have been made on the points of 50% growth inhibition, the fold increase of resistance shown to each compound by the r ... | 1977 | 137981 |
| exotic diseases. ounce of prevention or pound of cure? | with the growth of international travel, exotic diseases have assumed increasing importance to the physician. they can be effectively prevented by the use of commonsense measures. the physician should be prepared to offer advice on food, drink, and use of prophylactid drugs and to give needed immunizations to patients planning to travel. the biggest pitfall in diagnosis of exotic disease is failure to connect a history of travel with the signs and symptoms. an answer to the simple question, "whe ... | 1977 | 142245 |
| resistance to antimalarials by plasmodium falciparum in burma. | | 1977 | 142304 |
| a simple method for the isolation of actin from myxomycete plasmodia. | a new, simple method for the isolation of actin from myxomycete plasmodia has been developed. plasmodium myosin b was incubated at 55 degrees c for 15 min in the presence of atp or was treated with 90% acetone. by this treatment myosin was denatured completely. actin was then extracted with a dilute atp and cysteine solution from the heat- or acetone-treated myosin b. the method is simple and almost pure actin was obtained in high yield. the purified g-actin polymerized to f-actin on addition of ... | 1977 | 142766 |
| physarum action. observations on its presence, stability, and assembly in plasmodial extracts and development of an improved purification procedure. | actin is readily extracted from plasmodia of physarum polycephalum by low ionic strength solutions which do not solubilize the plasmodial myosin. the actin in such extracts exists predominantly as a monomer which slowly denatures, apparently via removal of bound nucleotide, and is subsequently proteolyzed. however, the native monomeric actin can be induced to assemble into polymeric arrays under appropriate solvent conditions. actin assembly is dependent on the addition of atp and is a function ... | 1977 | 143958 |
| [susceptibility of anopheles maculipennis atroparvus v. thiel to infection with the azerbaijan strains of plasmodium of tertian malaria (plasmodium vivax)]. | | 1977 | 144846 |
| electron microscope cytochemistry of host-parasite membrane interactions in malaria. | two membrane-bound enzymes were localized by electron microscope cytochemical techniques in plasmodium lophurae and its host erythrocyte. parasites were prepared by saponin lysis, french pressure cell lysis, or anti-red blood cell serum lysis; infected and uninfected erythrocyte ghosts were prepared by saponin or french pressure cell lysis. enzyme incubations were performed on unfixed cells. adenosinetriphosphatase (ec 3.6.1.3) activity was found on the inside of the ghost membrane and on the in ... | 1977 | 145326 |
| reversible superprecipitation and bundle formation of plasmodium actomyosin. | synthetic actomyosin from plasmodium was found to undergo reversible superprecipitation upon addition of atp. according to electronmicroscopic investigation upon clearing, short myosin filaments of about 0.2 micron in length appeared predominantly coexisting with actin filaments, and after superprecipitation, bundles of actin filaments were formed where short myosin filaments or myosin molecules were bound to the side of the bundle, making a whisk-like structure. the turbidity and the atpase act ... | 1978 | 148295 |
| serological responses to plasmodium and toxoplasma in school children from two areas in burma. | | 1977 | 149374 |
| [results of an immunological examination of the population of the moldavian ssr in connection with cases of inoculation quartan malarian]. | | 1978 | 149903 |
| [susceptibility of anopheles maculipennis sacharovi and anopheles maculipennis subalpinus mosquitoes to infection with the causative agents of tropical malaria brought in from africa]. | | 1978 | 149904 |
| [immunization against malaria and its possible effects on the control of the disease]. | | 1978 | 153759 |
| [imported malaria in leningrad in 1975-1977]. | | 1979 | 154588 |
| malaria infection in mice. plasmodium berghei infection in mice: a model for immune complex disease and autoimmunity. | | 1979 | 157057 |
| immunologic aspects of renal lesions associated with malaria. | studies on experimental models of infections and observations in man indicate that immune complexes (ic) play an important role in the pathogenesis of nephropathies associated with malaria. all present evidence suggests that ic preformed in circulation localize in the glomeruli and initiate the lesions. in acute lesions, typical of falciparum infections in man, the depositions of ic are found quite soon after infection; glomerular injury is reversible, and these cases respond well to antimalaria ... | 1979 | 160963 |
| [evaluation of the repercussions on parasitic endemias (malaria, bilharziasis, onchocerciasis, dracunculosis) of the construction of 57 dams in the mandara mountains (north cameroun)]. | | 1979 | 161205 |
| [chemotherapy of infections in the third world]. | | 1979 | 162323 |
| threshold phenomena in chemoreception and taxis in slime mold physarum polycephalum. | the plasmodium of physarum polycephalum reacts to various kinds of chemicals substances and moves towards or away from them. threshold concentration of recognition of chemicals was examined in terms of membrane potential and of the averaged motive force of tactic movement by using a double-chamber method, i.e., a single plasmodium was placed between two compartments through a narrow ditch, and differences in membrane potential and in pressure between two compartments were measured. results are s ... | 1975 | 163890 |
| erythrocyte membrane alterations induced by plasmodium simium infection in saimiri sciureus: relation to schüffner's dots. | the nature of erythrocyte membrane alterations in plasmodium simium infections was determined employing light microscopy, carbon replication and transmission electron microscopy. light microscopy of giemsa stained preparations shows that infected cells initially acquire a faint stippling (schuffnerization) which becomes pronouced with subsequent parasite development. enlargement of the host cell usually accompanied stippling. both phenomena appear to depend on host cell age since infected mature ... | 1975 | 165280 |
| coenzyme a requirement of malaria parasites: enzymes of coenzyme a biosynthesis in normal duck erythrocytes and erythrocytes infected with plasmodium lophurae. | normal duck erythrocytes and erythrocytes infected with plasmodium lopharae have all of the enzymes for coenzyme a biosynthesis, whereas parasites freed from their host cells have non. since erythrocytefree cultivation of p. lophurae requires an exogenous source of coenzyme a, this parasite must obtain its coenzyme a entirely from the host cell during infection. | 1975 | 166388 |
| parasitology survey and seroepidemiology of amoebiasis in south kalimantan (borneo), indonesia. | a parasitology surevy was conducted among inhabitants of 7 villages in 3 regencies in south kalimantan province, indonesia. a total of 2,169 stool specimens, 2,756 blood smears and 1,027 serum specimens were obtained, representing samples from approximately 10%, 12% and 5% of the population, respectively. one to 8 different intestinal parasitic infections were detected in 97% of the people. those parasites most frequently found were trichuris trichiura (83%), ascaris lumbricoides (79%), and hook ... | 1975 | 167454 |
| [dna-, rna-, lipidsynthesis and the specific activity of the glucose-6-phosphate dehydrogenase and glucose-6-phosphatase in the different morphologic stages of plasmodium vinckei]. | dna-, rna-, and lipidsynthesis, glucose-6-phosphate-dehydrogenase, glucose-6-phosphatase and succinate-dehydrogenase were studied in the different morphologic stages of blood schizogony of plasmodium vinckei. for the separation of these stages of the maturation cycle a discontinuous ficoll-density gradient was developed. by this method the morphologic stages were separated and obtained in sufficient amounts. dna-, rna- and lipidsynthesis was not continuous in the intraerythrocytic cycle of the p ... | 1975 | 167481 |
| enhanced cytotoxicity in mice of combinations of concanavalin a and selected antitumor drugs. | concanavalin a (con a) injected intraperitoneally at a dose of 50 mg per kg was not lethal for male balb/c mice. six hours after administration of 5 mg con a/kg, the proportioy 24 hr, the proportion of granulocytes had decreased to 56%. adiministration of 5 mg con a/kg 24 hr before 200 mg of 5[3,3-bis(2-chloroethyl)-triazeno]-imidazole-4-carboxamide per kg, or 100 mg of 5-fluorouracil per kg resulted in a significant enhancement of lethality. simulatenous administration of 5 mg con a/gm and 10 m ... | 1975 | 168746 |
| nutritional control of differentiation (sclerotization) of the myxomycete physarum flavicomum. | during differentiation (sclerotization) of the myxomycete physarum flavicomum, the acellular phasmodium converts into numerous dormant cells surrounded by cell walls. this work establishes that a condition of nutrient imbalance triggers the differentiation process. specifically, the unavailability of an adequate spectrum of amino acids in the medium initiates the metabolic and morphological alterations characteristic of the sclerotizing plasmodium. in the absence of extracellular amino acids, th ... | 1975 | 168949 |
| protozoal viruses. | | 1976 | 179308 |
| tumorigenicity of epstein-barr virus (ebv)-transformed lymphoid line cells in autologous squirrel monkeys. | eight squirrel monkeys (saimiri sciureus) challenged with ebv or ebv-transformed slcl were naturally or experimentally infected with plasmodium knowlesi or pl. brasilianum. most of the animals had been splenectomized and unilaterally nephrectomized. three of these monkeys received one dose of 6 to 12 x 10(8) autologous slcl. these lines were derived from saimiri lymphoid cells permanently transformed by b-ebv in vitro. all three animals developed multiple undifferentiated malignant lymphomas and ... | 1976 | 179960 |
| from sharks to coenzyme q10. | | 1976 | 187031 |
| subcellular distribution of serine hydroxymethyltransferase in plasmodium lophurae. | | 1977 | 192978 |
| plasmodium chabaudi-infection of mice: specific activities of erythrocyte membrane-associated enzymes and patterns of proteins and glycoproteins of erythrocyte membrane preparations. | membrane preparations of erythrocytes from normal and p. chabaudi-infected mice and membrane preparations of p. chabaudi-infected and uninfected erythrocytes from infected mice and separated by zonal centrifugation were characterized by the pattern of proteins and extracted glycoproteins obtained by sds-polyacrylamide gel electrophoresis and by the specific activities of membrane associated enzymes. the protein pattern of the membrane preparation of infected erythrocytes showed similar differenc ... | 1977 | 193221 |
| plasmodium berghei: high pressure liquid chromatographic analysis of nucleotides from erythrocyte-free malarial parasites. | | 1977 | 195832 |
| [malarial hepatitis. apropos of a case]. | | 1977 | 206971 |
| biomedical survey in irian jaya (west irian), indonesia. | a biomedical survey was conducted in several areas of irian jaya, indonesia in july 1972 in association with an investigation of reports of a cholera outbreak. stool specimens, blood smears and sera were collected and examined for evidence of parasitic as well as other infectious diseases. a total of 114 stools were examined and the most commonly found intestinal parasites were trichuris trichiura (94%), ascaris lumbricoides (74%), hookworm (58%), entamoeba coli (15%), endolimax nana (8%), entam ... | 1977 | 208184 |
| [relations between malaria and burkitt's lymphoma]. | malaria, especially forest malaria, is the environmental factor which creates endemic conditions for the esptein-barr virus related burkitt's lymphoma. the plasmodium seems active through a mitogenic factor rather than through the so often invoked immunological depresssion. | 1977 | 208788 |
| ultrastructural and cytochemical observations on sporogenesis of myxobolus sp. (myxosporida: myxobolidae) from the common shiner notropis cornutus. | the structure and cytochemistry of spores of myxobolus sp. from plasmodia which occur in the gill filaments of the common shiner notropis cornutus were studied by light microscopy and by scanning and transmission electron microscopy. the thin-walled valves of the pyriform spores are thickened in the lateral sutural and apical regions. mucous material is associated predominantly with the posterior end of many spores. the plasmodium is surrounded by a syncytial wall bounded by 2 membranes. pinocyt ... | 1978 | 214551 |
| pyridoxine kinase in plasmodium lophurae and duckling erythrocytes. | pyridoxine kinase enzyme activity was greatly increased in duckling erythrocytes infected with plasmodium lophurae. pyridoxine kinase activity in parasites freed from erythrocytes was much greater than that of uninfected erythrocytes. the apparent km for pyridoxine of the parasite enzyme was 6.6 times 10(-5) m whereas the host red cell enzyme km was 1.9 times 10(-6) m. deoxypyridoxine inhibited host and parasite pyridoxine kinase activity with an apparent ki of 1.5 times 10(-6) and 8.6 times 10( ... | 1978 | 216802 |
| conversion of dihydroorotate to orotate in parasitic protozoa. | the conversion of dihydroorotate to orotate, one of the key reactions in the de novo pyrimidine biosynthetic pathway, has been studied in a number of parasitic protozoa. enzyme activities capable of carrying out this reaction were detected in six members of the kinetoplastida (trypanosoma brucei, trypanosoma congolense, trypanosoma vivax, trypanosoma lewisi, trypanosoma cruzi, leishmania enriettii) and three members of the genus plasmodium (p. knowlesi, p. berghei, p. gallinaceum). the mechanism ... | 1979 | 217438 |
| some infectious diseases of wild vervet monkeys (cercopithecus aethiops pygerythrus) in south africa. | our surveys indicate that nearly all batches of vervet monkeys arriving at the national institute for virology from various areas of south africa, are infected with foamy viruses and there is evidence that intra-urterine infection also occurs. monkeys from certain areas of south africa are apparently infected with the protozoal parasite entopolypoides macaci in a sub-clinical state which becomes active when the monkeys are splenectomised. serological studies indicate that infections with schisto ... | 1978 | 218005 |
| sarcomas induced by injection of simian virus 40 into neonatal cfw mice. | sarcomas were induced in cfw mice by the iv inoculation of simian virus 40 (sv40) in neonatal animals. infection with murine malaria parasites, plasmodium berghei yoelli, decreased the latency and increased the incidence and invasiveness of the tumors. all mice given both sv40 and p. berghei yoelli had sarcomas of the liver and spleen at 9 months of age. at 11 months of age, 70% of the sv40-inoculated mice had sarcomas of the liver indistinguishable from those in the group given both pathogens. ... | 1979 | 225503 |
| malaria enhances cyclic amp production by immature erythrocytes in vitro. | | 1979 | 225632 |
| [severe forms of imported malaria concerning three pernicious attacks and a black water fever (hemoglobinuria) (author's transl)]. | four severe cases of imported malaria are reported here. three of them are pernicious and the fourth is a black water fever (hemoglobinuria). the difficulties of initial diagnosis are exposed. there was no mortality in these four cases which represent the annual recruiting of a multipurpose intensive care unit. but the complications are severe in contradiction with easy effective chemoprophylaxis. the principles of treatment and prophylaxis are resumed in the light of these four observations. | 1979 | 230588 |
| [antimalaria fluorescent antibodies evolution in young children living in a stable malaria area (author's transl)]. | the detection of malarial fluorescent antibodies have been performed in an abidjan dispensary on 30 newborn babies with their mothers, 30 children 3 months old and 120 children from 6 to 24 months. this survey took place during the small rainy season and it demonstrates that: --synthesis of specific antibodies is significantly starting after the 3rd month; --the rise, after six months, of the malarial antibodies is parallel to the plasmodic index checked during the same period in the same area; ... | 1979 | 231178 |
| nor-mdp, saponin, corynebacteria, and pertussis organisms as immunological adjuvants in experimental malaria vaccination of macaques. | vaccination of primates against malaria using antigen derived from erythrocytic parasite stages has been most successful where freund's complete adjuvant has been employed. since this adjuvant is clinically unacceptable its replacement is a matter of urgency.in the present work a muramyldipeptide derivative (nor-mdp) given in mineral oil has proved to be partially effective as an adjuvant for merozoite vaccination of macaca mulatta against plasmodium knowlesi, and saponin has proved to be effect ... | 1979 | 232428 |
| development and suppression of a population of late-adhering macrophages in mouse malaria. | changes in phagocytic and adherent cell numbers were compared during the course of infections of mice with plasmodium yoelii (py) and p. berghei (pb) and in vaccinated mice challenged with homologous parasites. nucleated cells in the spleen increased in number in py-infected mice and were maximal at the time of recovery. the number of phagocytic cells increased in parallel, as did the number of blood leucocytes. rates of increase were accelerated in vaccinated mice. changes in pb-infected mice r ... | 1979 | 233150 |
| [radioisotope labeling of mosquitoes]. | | 1975 | 235819 |
| letter: latency in plasmodium vivax infection. | | 1975 | 238313 |
| a calcium ion-dependent atp pyrophosphohydrolase in physarum polycephalum. | an activity of atp pyrophosphohydrolase (ec 3.6.1.8) was found in the soluble fraction of the plasmodium of physarum polycephalum. the products of the enzyme reaction were inorganic pyrophosphate and 5'-amp in equimolar quantities. the enzyme had a pronounced requirement for ca2+ with high specificity. mg-2+ was not an essential cofactor but stimulated the enzyme activity about 2.5-fold of the control. the enzyme hydrolyzed itp, gtp and beta,gamma-methylene atp at a limited rate. among inhibitor ... | 1975 | 238634 |
| patterns of plasmodium vivax recurrence in a high-incidence coastal area of el salvador, c. a. | during field studies carried out in 1971, 1972 and 1973 in a highly malarious coastal area of el salvador, it was possible to collect information on the patterns of plasmodium vivax parasite occurrence in a large number of infected individuals. in most of the persons who had experienced a malaria attack during the high transmission period in june, july, august and september, renewed activity occurred 5 to 8 months later, during the low transmission season the next year. subsequent activity in th ... | 1975 | 239603 |
| malaria studies in vitro. iv: chloroquine resistance and the intracellular ph of erythrocytes parasitised with plasmodium berghei. | the erythrocytic stages of strains of plasmodia sensitive to chloroquine (cq) concentrate some three to six times more drug than cq-resistant strains. a simple, but so far untested hypothesis is that the intracellular ph of drug resistant strains is higher than that for sensitive strains. this would result in a reduced accumulation of any weakly basic drug molecule (e.g. cq) which is capable of passive diffusion through the cellular membran. the mean intracellular ph of erythrocytes parasitised ... | 1975 | 239645 |
| observations on natural plasmodial infections in mosquitoes and a brief survey of mosquito fauna in belu regency, indonesian timor. | | 1975 | 241851 |
| an extracellular inducer of asexual plasmodium formation in physarum polycephalum. | asexual conversion of amoebae to plasmodia was studied in the colonia isolate of the myxomycete, physarum polycephalum. when a culture of colonia amoebae is grown on a bacterial lawn, a period of amoebic growth precedes the appearance of cells committed to the plasmodial state. the onset of plasmodium production appears to be related to amoebic nutrition since cultures supplied with fewer bacteria display earlier differentiation. for a period of time after differentiation is initiated, conversio ... | 1977 | 265558 |
| the nephrotic syndrome in papua new guinea: aetiological, pathological and immunological findings. | | 1977 | 269685 |
| isolation of malaria merozoites: release of plasmodium chabaudi merozoites from schizonts bound to immobilized concanavalin a. | the ability of concanavalin a to bind erythrocytes but not malarial parasites was used for the development of a method of merozoite isolation: cells from infected blood were allowed to bind to a column of concanavalin a linked to sepharose beads and merozoites naturally released by maturation of the schizonts bound to the gel were collected. the principle of this method allows its application to several plasmodium species. the kinetics of merozoite production and the quality of the preparations ... | 1978 | 283417 |
| the relevance of research to the global antimalaria programme. | | 1977 | 303946 |
| recent advances in understanding the invasion of erythrocytes by merozoites of plasmodium knowlesi. | previous observations on the process of invasion by p. knowlesi are briefly reviewed and new findings concerning the adhesion of parasites to erythrocytes and their intracellular passage are reported. merozoites adhere to erythrocytes by means of a well-defined coat with the cytochemical characteristics of glycoprotein. this coat has receptors that engage in at least three distinct types of attachment. the ensuing invagination of the erythrocyte surface has two phases, the first consisting of an ... | 1977 | 303947 |
| transport of carbohydrates by malarial parasites. | the red cells of malaria-infected mice and ducks have an increased permeability to glucose. | 1977 | 303948 |
| salvage syntheses and their relationship to nucleic acid metabolism. | the intraerythrocytic stages of plasmodia are capable of synthesizing purine nucleotides and apparently deoxycytidylate by salvage syntheses. data obtained by studying the incorporation of radioactive precursor molecules into intact cells and kinetic experiments on purified enzyme preparations suggest biosynthetic routes which, generally, are similar to those of the host's cell metabolism. however, details on the regulation of both the uptake of nucleosides and bases into the intraerythrocytic s ... | 1977 | 303949 |
| a quantitative long-term cryobiological study of malarial parasites. | a study spanning 10 years indicates that the erythrocytic stages of malarial parasites can be stored indefinitely in the vapour phase of liquid nitrogen without significant loss of infectivity. the results also suggest that loss due to the recovery procedures exceeds any loss that may have occurred during freezing and thawing. when feasible, large pools of material should be divided into smaller aliquots before storing the organisms at a low temperature, since freezing a second time produces sig ... | 1977 | 303950 |
| purification of intracellular forms of plasmodium chabaudi and their interactions with the erythrocyte membrane and with serum albumin. | a procedure using bovine serum albumin gradients was developed for the separation of p. chabaudi-infected mouse erythrocytes from uninfected cells. this procedure can be used for the purification of erythrocytes containing different developmental stages of the parasite. the purified parasites were able to synthesize in vitro all the proteins that they are capable of synthesizing in vivo. the intracellular forms of p. chabaudi were found to be associated with erythrocyte membrane components and t ... | 1977 | 303951 |
| biochemical markers for strain differentiation in malarial parasites. | genetic differences between micro-organisms can be identified by studying variations in enzyme forms and dna characteristics. enzyme electrophoresis has revealed considerable genetic diversity in populations of malarial parasites and has enabled populations reproductively isolated from one another to be identified. studies on rodent malarial parasites from four regions of africa have shown that each species and subspecies can be distinguished by its pattern of enzyme forms. in subspecies in whic ... | 1977 | 303952 |
| summary of discussions on the biology of the malaria parasite. | | 1977 | 303953 |
| interactions of rodent malarial parasites with friend erythroleukemia cells in vitro. | the ability of plasmodium chabaudi and p. yoelii to bind to friend erythroleukemia cells in vitro was examined. extensive binding of p. yoelii and weaker binding of p. chabaudi was observed. binding to mouse fibroblasts was not seen, although there was some binding to cells of a mouse mastocytoma. the binding of p. yoelii to friend cells was sensitive to specific antiserum. the development of p. berghei and p. yoelii in friend cells was followed by microscopic examination and measurement of the ... | 1977 | 303954 |
| should cultivated exoerythrocytic parasites be considered as a source of antigen for a malaria vaccine? | routine procedures for growing exoerythrocytic stages of avian malaria parasites in continuous culture have been available for many years. this system, adapted for the cultivation of mammalian forms, would have certain advantages in vaccine production, the great advantage being the potential for self-replication by both the host cell and the parasite. many obstacles must be overcome, however, before efforts in this direction can be successful. the recent demonstration that merozoites of the exoe ... | 1977 | 303955 |
| future orientation of research. | | 1977 | 303957 |
| plasmodium chabaudi in mice. adoptive transfer of immunity with enriched populations of spleen t and b lymphocytes. | thymectomized nih and c57bl mice were more susceptible to plasmodium chabaudi than controls, indicating a role for t cells in acquired immunity to the parasite. enriched populations of t and b cells were prepared from the spleens of immune mice using nylon-wool columns, and were adoptively transferred to syngeneic non-irradiated mice or mice irradiated with 600 or 800 rad. some immunity could usually be transferred with immune t, b and glass-wool (g.w.) filtered spleen cell populations. in the h ... | 1978 | 306962 |
| cell-mediated immunity in mice vaccinated against malaria. | mice vaccinated with a formalin-fixed preparation of either plasmodium berghei or p. yoelli exhibited delayed type hypersensitivity (dth) to the homologous antigen. this manifested itself in increased delayed thickening of antigen-challenged pinnae of the vaccinated mice as compared to the non-vaccinated controls. dth was also evident in the vaccinated mice using the homing of radio-labelled bone marrow cells (bmc) to the delayed lesion as a criterion of reactivity. when p. yoelii vaccinated mic ... | 1978 | 310745 |
| t-cell immunity to malaria in the b-cell deficient mouse. | some b-cell deficient mice drug-rescued with clindamycin hcl from otherwise lethal infections with plasmodium yoelii resisted subsequent challenge with the same parasite despite the fact that they lacked detectable antibody to plasmodia. parasitemias remained patent but at low levels (less than or equal to 5%) in these mice for prolonged periods of time, suggesting that some t-cell function independent of antibody formation can in part mediate immunity to malaria. | 1979 | 312025 |
| abnormal haemoglobins in the sudan savanna of nigeria. i. prevalence of haemoglobins and relationships between sickle cell trait, malaria and survival. | the prevalence of different haemoglobins and their interaction with malaria have been studied in garki, kano state, nigeria. sickle cell trait was present in 24% of newborn and 29% of those aged over five years. hb.ac was present in 0.7%. frequency of both haemoglobin variants was greater in hausa than fulani. sickle cell anaemia was almost invariably fatal in early childhood. the distribution curve of percentage of hb.s in sickle cell trait subjects was normal, and did not demonstrate any high ... | 1979 | 315211 |
| abnormal haemoglobins in the sudan savanna of nigeria. iii. malaria, immunoglobulins and antimalarial antibodies in sickle cell disease. | subjects with sickle cell disease were identified in (i) a whole population sample (2742) garki district, kano state, nigeria, and in (ii) the 534 infants born into the population during five years. eleven (2.1%) newborn had hb.ss, as was expected from gene frequency (0.146). prevalence was maintained in the first year of life, but fell to 0.4% at one to four years and to 0.05% (one person) over the age of nine years. antimalarial intervention for two transmission seasons was followed by an appa ... | 1979 | 315213 |