immunological relationships of long island isolates of babesia microti.studies to detect strain differences among two rodent-derived and one human-derived babesia microti isolates from long island were undertaken, using various methods. superinfection experiments using the homologous and heterologous isolates showed cross-protection. all hamsters were resistant to superinfection challenges of increasing dosages of both the homologous and heterologous isolates. attempts to infect other laboratory animals with the long island isolates of b. microti were successful in ...197988904
resistance of mice suppressed for igm production to babesia microti infection.the immunological mechanisms responsible for overcoming infections with babesia, an intra-erythrocytic protozoan, are not fully understood. although high titres of specific anti-babesial antibodies have been observed in several species of animals, and protection has been obtained by transfer of large volumes of recovery serum, the role of antibody in the immune response to an infection is uncertain. the present study investigates the nature of b-cell participation during babesia microti infectio ...1979317837
babesia microti: morphology, distribution and host relationship in germany.a short review has been given about recent studies on babesia microti in natural animal host's near munich (southern germany). an infected area has been studied in order to elucidate the outdoor relationship between the local strains and their preferred hosts, the european field vole microtus agrestis. the seasonal variation of the parasites prevalence in voles shows a rise in the early summertime (71% of the catches infected). roundish forms predominate in the erythrocytes. multiplication never ...1979388948
immunity to plasmodium yoelii and babesia microti: modulation by the cba/n mice carry an x-linked recessive defect expressed in cells of the b cell lineage. the major deficiency in these mice is an almost complete inability to respond to certain thymus-independent antigens, such as pneumococcal polysaccharide type iii (s iii). we have examined the responses of mice carrying the cba/n x-chromosome to the malaria parasite plasmodium yoelii and the piroplasm babesia microti. we have found that the duration and severity of these infections is increased in mice carryi ...1979317444
protection of mice against haemoprotozoan babesia microti with brucella abortus strain 19.when brucella abortus strain 19 is given intraperitoneally to mice it protects them against subsequent infection with large doses of babesia microti. the protection obtained was more effective when b. abortus was given intraperitoneally than when it was injected subcutaneously. this non-specific protection seems to be best explained by the stimulation of macrophages so as to release a mediator which limits the intracellular replication of the parasites.197895914
susceptibility of five strains of mice to babesia microti of human outbred (cf1) and four inbred (balb/c, c57, cba and c3h) strains of mice were tested for susceptibility to babesia microti of human origin. of these, intact c3h mice developed higher parasitemia than all other intact mice, while balb/c mice developed the highest parasitemia among splenectomized mice. susceptibility was not related to h-2 haplotype in any obvious way. because c3h and balb/c mice developed relatively high initial peak parasitemias, the parasite was serially passaged in both of ...1979480073
protection of mice against babesia microti with cord factor, coam, zymosan, glucan, salmonella and listeria.cord factor (trehalose 6-6' dimycolate). coam (chlorite-oxidized oxyamylose), zymosan, glucan, salmonella enteritidis 11rx and listeria monocytogenes were found to protect mice against subsequent infection with babesia microti, an intra-erythrocytic protozoan parasite. this protection was not observed after injection of staphylococcus epidermidis, a viridans group streptococcus, thioglycollate, or colloidal carbon. all the agents which protect against b. microti have also been reported to induce ...1979121772
resistance to babesia spp. and plasmodium sp. in mice pretreated with an extract of coxiella burnetii.mice injected intravenously with a commercially available extract of coxiella burnetii prepared for use as the antigen in the complement fixation diagnostic test for q fever were subsequently resistant to infection with babesia microti, babesia rodhaini, and plasmodium vinckei petteri. the parasites appeared to die inside circulating erythrocytes. protection was unaffected by exposing the pretreated mice to 900 rads on the day before they were infected. to explain these findings, it is postulate ...1979378850
role of deer in the epizootiology of babesia microti in massachusetts, usa. 1979544828
biochemistry of intraerythrocytic parasites. ii. comparative studies in carbohydrate metabolism.comparative studies were carried out on the glucose catabolism of mouse erythrocytes infected with plasmodium berghei, plasmodium yoelii, babesia rodhaini, babesia microti and anthemosoma garnhami, as well as on uninfected erythrocytes and reticulocytes. the results showed that there was little qualitative difference between the glucose utilization and lactate production of the parasites although quantitative differences between malaria parasites and piroplasms were observed. the rate of glucose ...1979386968
experimental babesia microti infections in non-splenectomized macaca mulatta.eight non-splenectomized macaca mulatta were inoculated intravenously with strains of babesia microti that originally were isolated from 2 human cases of babesiosis and then were maintained in hamsters in the laboratory. patent infections developed in 7 animals with peak parasitemias of 496 to 3,906 organisms/mm3 blood. prepatent periods ranged from 15 to 46 days. parasitemia persisted for at least 90 days in all animals and in one, organisms were still present 559 days after inoculation.1979109604
failure of chloroquine in human babesiosis (babesia microti): case report and chemotherapeutic trials in hamsters.the failure of a 3-week course of chloroquine to eliminate an infection of babesia microti acquired on martha's vineyard led to tests of selected drugs in hamsters infected with the strain from this patient. the results showed response to several antitrypanosomal drugs (pentamidine and 4,4'-diazoaminobenzamidine) but not to antimalarial drugs (chloroquine, sulfadiazine, and pyrimethamine).1978626449
babesia microti infection in man: evaluation of an indirect immunofluorescent antibody indirect immunofluorescent antibody test was used to detect antibody to babesia microti in human sera. nine patients from nantucket island, massachusetts infected with b. microti had serum titers greater than or equal to 1,024. of 84 control sera from new york city residents, 246 sera from patients with possible exposure to ticks, and 36 sera from patients with suspected or confirmed tick bites, none was reactive at titers of 1:16 or above. the within-test reproducibility was within one fourf ...1978343608
babesiosis in long island. host-parasite relationships of rodent- and human-derived babesia microti isolates in hamsters.the effects of splenectomy and size of inoculum on response of hamsters to three isolates of babesia microti (two rodent- and one human-derived) from long island were studied. splenectomy of hamsters did not enhance susceptibility to the rodent isolates of b. microti at a dosage of 5 x 10(7) parasites. larger parasite inocula produced shorter prepatent periods and slightly shorter duration of infection in intact hamsters. inoculum size was not contributory to mortality of hamsters or to pathogen ...1978365005
heterologous immunity between piroplasms and malaria parasites: the simultaneous elimination of plasmodium vinckei and babesia microti from the blood of doubly infected mice.mice which have recovered from infections with the avirulent piroplasm babesia microti are also resistant to challenge with the virulent malaria parasite plasmodium vinckei. in mice infected with p. vinckei before the peak of the b. microti infection the numbers of malaria parasites in the blood increase until that peak and are then eliminated at the same time as the piroplasms. in mice infected with p. vinckei at or after the peak there is no apparent multiplication and the malaria parasites be ...1978622306
effect of immune serum on the growth of babesia microti in hamster erythrocytes in short-term culture.short-term in vitro culture of babesia microti was obtained. immune hamster serum had an inhibitory effect on the growth of b. microti in vitro. it is suggested that these antibodies act by preventing penetration of erythrocytes by the parasite.1979573243
babesia microti and babesia hylomysci: spleen and phagocytosis in infected mice. 1979421763
babesia microti infection in man. 1977578184
the occurrence of babesiasis affecting small terrestrial mammals and the importance of this zoonosis in europe.a short survey is given of the occurrence of babesiasis affecting small terrestrial mammals in some parts of europe. results obtained in studies of 7,038 small terrestrial mammals (42 species) from czechoslovakia, austria, hungary, yugoslavia and bulgaria, show the distribution of babesia microti in these countries. the authors found babesias in the following host species: neomys anomalus, clethrionomys glareolus. microtus arvalis, m. agrestis, apodemus agratius, a. flavicollis, a. sylvaticus an ...1977903030
fatal experimental babesia microti infections in the norwegian lemming, lemmus lemmus (l.).experimental infections of babesia microti in laboratory-reared clethrionomys glareolus revealed that approximately 15% of the erythrocytes were infected with single ring forms during peak parasitemia. infected erythrocytes could be detected in blood smears up to one month post infection. c. glareolus treated with a single injection of depo-medrol i.m. two days prior to infection displayed a four-fold increase in number of infected erythrocytes at peak parasitemia, 35% of which contained more th ...1978357267
immunodepression in babesia microti infections.infection with the avirulent piroplasm babesia microti in mice is accompanied by a marked depression in the ability of the mice to mount an immune response to sheep red blood cells. the period of immunodepression begins 3 days after peak parasitaemia and is maximal 4 days later. thereafter, there is a slow return to normal immune responsiveness, correlated with the gradual disappearance of the parasites from the blood. both igm and igg responses are depressed. cell-mediated responses as determin ...1977337221
protection of mice against babesia spp. and plasmodium spp. with killed corynebacterium parvum.mice which had been pre-treated with killed corynebacterium parvum given intravenously or intraperitoneally, but not subcutaneously, were completely resistant to infection with babesia microti or b. rodhaini, and were protected from death caused by plasmodium vinckei or p. chabaudi infection. there is evidence that the parasites died within circulating erythrocytes. this occurred much too soon for a specific antibody response to be evoked, and no antibody could be detected by the indirect fluore ...1977320544
babesia microti: pathogenesis of parasite of human origin in the hamster. 1975805058
ribosomal dna probe for differentiation of babesia microti and b. gibsoni isolates.the objective of this study was to determine whether different isolates of babesia microti could be distinguished from morphologically similar isolates of b. gibsoni by using a ribosomal dna (rdna) probe. a babesia-specific rdna probe was obtained by polymerase chain reaction amplification of sequences from b. microti dna using universal primers directed against highly conserved portions of the eukaryotic 16s-like rrna gene. the chemiluminescent rdna probe hybridized to southern blots of restric ...19921349901
an electron microscopic study of babesia microti invading erythrocytes.intracellular sporozoan parasites invade the host cell through the invagination of the plasma membrane of the host and a vacuole is formed which accommodates the entering parasite. the vacuole may disappear and the invaginated membrane of the host then becomes closely apposed to that of the parasite's own membrane. as a result the parasite is covered by two membranes. members of the class piroplasmea differ from other sporozoa in that their trophozoites are covered by a single membrane. by scree ...1976820430
neurologic complications following the treatment of human babesia microti infection with diminazene aceturate.a 65-year-old man infected with babesia microti failed to respond to therapy with oral chloroquine phosphate. he was then successfully dreated with diminazene aceturate, an experimental anti-protozoal agent. after his recovery from babesiosis, the patient developed acute idiopathic polyneuritis (landry-guillain-barré syndrome), which was probably related to his diminazene therapy.1979572145
human babesiosis on nantucket island. clinical features.between 20 july and 15 octoboer 1975, five cases of human infection with babesia microti were diagnosed on nantucket island, massachusetts. the illness was characterized by fever, drenching sweats, shaking chills, myalgia, arthralgia, extreme fatigue, and a mild-to-moderate hemolytic anemia. none of the patients had a history of splenetomy. although all patients responded symptomatically to treatment with oral chloroquine phosphate, parasitemia and fatigue frequently persisted for several weeks ...1977556920
detection of babesia microti by polymerase chain reaction.human babesiosis, which is caused by infection with the intraerythrocytic malarialike protozoan babesia microti, has recently been diagnosed with increasing frequency in residents of new england. diagnosis is difficult because of the small size of the parasite and the sparse parasitemia that is characteristic of most infections with this pathogen. we generated b. microti-specific dna sequence information by universal primer amplification of a portion of the eukaryotic 16s-like gene; this was fol ...19921500517
human babesiosis: the isolation of babesia microti in golden hamsters. 1977915626
immunity to intra-erythrocytic protoza.intra-erythrocytic inclusion bodies were seen in giemsa-stained smears of peripheral blood from mice infected with babesia microti. these bodies, which were probably the pyknotic remnants of dead protozoa, increased as parasitaemia fell and the animal recovered. it is suggested that a soluble mediator liberated by cells of the host during infection penetrates the red blood-cell and leads to degeneration of the parasite.197553606
[ultrastructure of intraerythrocyte forms of babesia microti (strain munich and thun) with reference to reproduction and nutrition of the parasite]. 1978747626
intraerythrocytic 'gametocytes' of babesia microti and their maturation in ticks. 1979540277
transmission of babesia microti using various species of ticks as vectors. 1979512774
human babesiosis: reservoir in infection on nantucket island.examination of blood films from six species of rodents and lagomorphs on nantucket island disclosed infections with babesia microti in all of five microtus pennsylvanicus (field mice) and 31 of 39 peromyscus leucopus (white-footed or deer mice). six human cases of clinical babesiosis have recently been diagnosed on the island.1976769166
formation of merozoites in intraerythrocytic babesia microti: an ultrastructural study. 1977884632
changes of splenic lymphocyte subpopulation in mice inoculated with babesia microti and babesia rodhaini.changes of splenic lymphocyte subpopulation after babesia microti and babesia rodhaini inoculation in mice were examined by flow cytometric analysis. the b. microti inoculated mice showed a longer period of time from inoculation to the onset of increase or decrease parasitaemia (%), packed cell volume, total spleen cell numbers and surface immunoglobulin positive splenic cell numbers than respective periods in b. rodhaini inoculated mice. the thy-1 positive cell numbers in b. microti inoculated ...19921477155
[occurrence, host range and seasonal prevalence of babesia microti (frança, 1912) in rodents of southern germany (author's transl)]. 1978741855
babesiosis: an underdiagnosed disease of children.babesiosis is a malaria-like illness caused by the intraerythrocytic parasite babesia microti and is transmitted by the same tick that transmits borrelia burgdorferi, the causative agent of lyme disease. babesiosis is well recognized in adult residents of southern new england and new york but has been described in only five children. to determine whether children are infected with b microti less often than are adults, a prospective serosurvey was carried out on block island, ri, where babesiosis ...19921594345
the nature of immunity against babesia hylomysci and b. microti infections in mice.mice which have recovered from babesia microti infection lose their parasitaemia as soon as three weeks after recovery and become solidly immune. this sterile immunity is not affected by splenectomy and may last for the life of the mouse. mice which have recovered from b. hylomysci infection continue to harbour parasites at a subpatent level and spontaneous relapses were common after recovery. hence the type of immunity which developed against this parasite is premunition and may last for life. ...1977921361
splenomegaly and reticulocytosis caused by babesia microti infections in natural populations of the montane vole, microtus montanus.a survey for babesia microti in rodents was conducted at six sites within grand teton national park, wyoming. blood and spleen smears, hematocrits, and reticulocyte counts were made on all of the animals to evaluate parameters for the diagnosis of babesiosis. ticks were removed for identification. of 257 microtus montanus, 103 were infected with b. microti. in addition, five of 12 microtus pennsylvanicus and one of three arvicola richardsoni were parasitized by b. microti. peromyscus maniculatus ...19911818201
babesia bovis, babesia bigemina, babesia canis, babesia microti and babesia rodhaini: comparison of ribosomal rna gene organization.the three ribosomal dna (rdna) units have been cloned from an australian isolate of babesia bigemina. the organization of the units is very similar to that reported for a mexican isolate of b. bigemina. in babesia canis four rdna units have been identified. both babesia rodhaini and babesia microti contain two different rdna units. a small number of different rdna units appears to be a common feature of this group of protozoa. restriction enzyme analysis of the rdna units form these species and ...19921428519
babesia microti, human babesiosis, and borrelia burgdorferi in connecticut.babesia microti was isolated from a white-footed mouse (peromyscus leucopus) that was captured in southeastern connecticut in 1988, when the first human case of babesiosis acquired in connecticut was recognized. to date, 13 cases of babesiosis have been reported in connecticut, the largest number of human cases reported on the mainland united states. two of nine patients quiried remembered a prior tick bite. since babesia parasites are known to be vectored only by ticks, we surmise that 12 of th ...19911757548
babesiosis in a connecticut resident.fewer than 200 confirmed cases of babesiosis have been reported in the last decade. most cases in the united states have occurred on cape cod, nantucket island, and long island. babesia microti, a malaria-like protozoan that parasitizes erythrocytes, is responsible for this illness in the united states. infection is often subclinical but may be fulminant, especially in infants, the elderly, and in asplenic patients. symptoms are nonspecific, usually consisting of fever and myalgias. common labor ...19902225809
feeding mechanisms in extracellular babesia microti and plasmodium lophurae.although large hemoglobin inclusions are observed in intraerythrocytic babesia microti parasites, they are absent from parasites freed of hamster red cells by immune lysis with anti-hamster erythrocyte serum. babesia microti has no cytostome. this parasite, therefore, does not appear to feed by phagocytosis of large boluses of hemoglobin, as does plasmodium. to determine whether babesia can pinocytose protein, free parasites were fed ferritin in an in vitro system. ferritin was taken up from the ...1976933077
ultrastructure of intraerythrocytic babesia microti with emphasis on the feeding mechanism.babesia microti is a highly polymorphic organism. to unravel its fine structure and the function of organelles it was necessary to resort often to serial sections. a single plasma membrane covers the organism. in trophozoites approaching reproduction, segments of double membranes can be found below the plasma membrane. in electron micrographs of poor resolution these segments of double membranes look like pieces of thick membranes and they were often thought to be a thick 2nd membrane. before th ...1976933078
microwave fixation: in situ tick (acari: ixodidae) histoanatomy, thin sectioning of tick tissues, and antigen preservation in mouse spleen.microwave irradiation was used for the fixation of eggs, nymphs, and adult boophilus spp. ticks. although optimal temperatures for fixation of the different tick stages varied, heating to 58 degrees c of adult ticks submerged in either pbs or fixative was found to be sufficient. after microwave fixation, whole adult ticks, hand held, were sectioned with a sharp razor blade. the resulting sections revealed the in situ histoanatomy of the tick. thin sections of ticks were obtained after either par ...19902280393
peromyscus leucopus and microtus pennsylvanicus simultaneously infected with borrelia burgdorferi and babesia microti.borrelia burgdorferi, the etiologic agent of lyme disease, and babesia microti, the causative agent of human babesiosis, were isolated from 71 and 57%, respectively, of 14 specimens of peromyscus leucopus and microtus pennsylvanicus collected from prudence and patience islands, r.i. both pathogens were isolated from five individual rodents. the presence of these two infectious organisms in the same mammal suggests that individual larval ixodes dammini may ingest both pathogens and subsequently t ...19863517038
intra-erythrocytic death of the parasite in mice recovering from infection with babesia mice recover from infection with babesia microti, abnormal forms of the parasite are present in some red cells. these forms are non-infective, indistinguishable by light microscopy from those present after treatment with amicarbalide, a babesicidal drug, and persist in splenectomized mice. electron microscopy confirmed that these abnormal forms are degenerating intra-erythrocytic parasites. in the absence of evidence for death of b. microti elsewhere in the body, it appears that infections of ...1977927888
absence of spirochaetes (borrelia burgdorferi) and piroplasms (babesia microti) in deer ticks (ixodes dammini) parasitized by chalcid wasps (hunterellus hookeri).an entomophagous wasp (hunterellus hookeri howard) parasitizes about a third of the host-seeking nymphal ixodes dammini spielman et al. ticks on naushon island in massachusetts (u.s.a.) where the agents of lyme disease (borrelia burgdorferi johnson et al.) and human babesiosis (babesia microti franca) are enzootic. following blood-feeding, wasp-parasitized ticks are destroyed by the developing wasp. the prevalence of either human pathogen in host-seeking ticks collected in wasp-infested sites is ...19872979518
piroplasms from taiwanese rodents.piroplasms from naturally infected bandicoot rats, bandicota indica (hodgson), and spiny rats, rattus coxinga (swinhoe), from taiwan caused parasitemias in a wide range of laboratory animals after syringe passage in laboratory rats. bandicoot and spiny rats could be infected with heterologous piroplasms, but neither species was susceptible to infection with the gray strain of babesia microti (frança). nevertheless, the taiwan piroplasms are probably a geographic strain of b. microti.1977881655
antibody levels in adoptively immunized mice after infection with babesia microti or injection with antigen fractions.specific igg anti-babesia antibodies could be detected by an elisa test in the serum of adoptively immunized mice which subsequently were infected with babesia microti. initially, higher igg antibody levels were present in the recipients of either untreated immune spleen cells or mitomycin c-treated immune spleen cells compared with the values in control mice which received the infection alone. subsequently, a marked anamnestic response occurred only in mice which received untreated immune splee ...19852415100
the effect of babesia microti on feeding and survival in its tick vector, ixodes trianguliceps.evidence is presented that babesia microti may promote its transmission amongst rodents by enhancing the feeding success and survival of its tick vector, ixodes trianguliceps. both the mean engorged weight of larval ticks and the percentage moult of larvae to nymphs increased as larvae fed on naive hosts later in the parasitaemic cycle up to a point a few days beyond the loss of a patent infection. this increased feeding success and survival was not dependent on the level of infection by b. micr ...19912038503
increase in micronucleated erythrocytes associated with babesiosis in syrian golden hamsters.the effect of infection by babesia microti, a tick-borne piroplasm endemic to the northeastern united states, on the temporal pattern of micronucleated erythrocyte frequencies in peripheral blood was investigated in male syrian golden hamsters. significantly greater frequencies of micronucleated erythrocytes occurred in the blood of infected hamsters from 26 to 46 days after injection with b. microti, the magnitude of which within individual hamsters correlated highly with the percentage of poly ...19892811934
geographical and temporal distribution of babesial infection in connecticut.human babesiosis was first recognized in connecticut in 1989, nearly 15 years after lyme disease, a similarly transmitted spirochetosis, was detected in the state. to determine the seroprevalence for the babesial pathogen and whether it was recently introduced, we used an indirect immunofluorescence assay to test for babesia microti antibody in 1,285 connecticut residents. four groups were studied: i, people seropositive for lyme disease, tested from 1986 to 1989; ii, randomly selected outpatien ...19911993742
short-tailed shrews as reservoirs of the agents of lyme disease and human determine whether short-tailed shrews (blarina brevicauda) serve as reservoir hosts for the lyme disease spirochete (borrelia burgdorferi) and the agent of human babesiosis (babesia microti), we examined nymphal ticks that had fed as larvae on shrews collected from 3 enzootic sites in coastal massachusetts for evidence of infection by either or both of these agents. xenodiagnosis indicated that 11 of 14 shrews were infected by b. burgdorferi. one of 3 piroplasm-infected shrews also infected t ...19902213411
resolution of acute malarial infections by t cell-dependent non-antibody-mediated mechanisms of immunity.while it is generally accepted that acute blood stage malarial infections are resolved through the actions of protective antibodies, we observed that resistance to acute infection with plasmodium chabaudi adami was mediated by t cell-dependent cellular immune mechanisms independent of antibody. we now report that acute blood stage infections caused by three additional murine hemoprotozoan parasites, plasmodium vinckei petteri, plasmodium chabaudi chabaudi, and babesia microti, appear to be contr ...19902387628
prostaglandin-mediated suppression of delayed-type hypersensitivity to infected erythrocytes during babesia microti infection in mice.the mechanism of suppression of delayed-type hypersensitivity (dth) to intraerythrocytic babesia microti which occurs during infection in mice was examined. the suppression was not specific for anti-parasite dth; infected mice immunized and challenged with sheep red blood cells had a similar depression of anti-sheep red blood cell dth. sublethal or lethal irradiation did not significantly alter the suppression of the dth response, and cyclophosphamide pretreatment of infected mice also had no ef ...19862944617
reduced dietary protein content suppresses infection with babesia microti.the influence of acute dietary protein restriction on the development of babesia microti infection in the mouse model was investigated. female mice consuming a diet either devoid of protein or adequate with respect to protein were infected with b. microti-parasitized erythrocytes and sacrificed 7 days later. absence of dietary protein resulted in a delay in the onset of infection and a significantly reduced peak parasitemia. non-specific antibody responses to heterologous erythrocytes and specif ...19883216813
detection of babesia bovis using dna hybridization.plasmids containing inserts of babesia bovis dna were prepared and clones suitable for use in the diagnosis of b. bovis infections were isolated. dot blot hybridization with dna from these plasmids, which probably contain repetitive sequences, can detect after an overnight exposure 100 pg of b. bovis dna, which corresponds to the amount of dna present in 50 microliters of 0.01% parasitemic erythrocytes. no detectable cross-hybridization was observed with babesia microti, plasmodium falciparum, p ...19863007751
effects of trypanosoma brucei and babesia microti infections on the primary granulomatous reaction to schistosoma eggs in mice.mouse infection with the blood protozoa trypanosoma brucei suppressed significantly the frequency and intensity of the primary granulomatous inflammatory response to eggs of the blood flukes schistosoma mansoni and s. bovis injected into the pulmonary microvasculature. in addition, the dynamics of the cellular infiltrate of the egg granuloma were strongly affected. it is suggested that the modulation of the granulomatous response is a result of impairment of the cell-mediated immunological respo ...19873110500
intraerythrocytic parasites and red cell deformability: plasmodium berghei and babesia the studies reported here, we examined the effects of two intraerythrocytic parasites (plasmodium berghei and babesia microti) on the deformability of their host red cells. red cell deformability was assessed by three criteria: 1) the prevalence of tank-treading (the tank-tread-like movement of the red cell membrane around its cytoplasmic contents), 2) elongation under fluid shear stress (the steady-state length: width ratio), and 3) the time required for the red cell to reduce its steady-sta ...19912018857
comparison of the effect of t-2 toxin with that of dexamethasone or cyclophosphamide on resistance to babesia microti infection in mice.the effect of t-2 toxin on host resistance to acute and latent babesia microti infections was evaluated in mice and was compared with the effects of the immunosuppressive drugs dexamethasone and cyclophosphamide. mice with acute or latent b microti infection were treated with 2 mg of t-2 toxin/kg of body weight, 0.2 mg of dexamethasone/kg, or 30 mg of cyclophosphamide/kg daily for 5 days. treatment with dexamethasone or cyclophosphamide caused significant (p less than 0.05) increases in babesia ...19883247926
the peritrophic membrane as a barrier: its penetration by plasmodium gallinaceum and the effect of a monoclonal antibody to ookinetes.we studied the point at which a monoclonal antibody (mab c5) to a surface protein (pgs25) on plasmodium gallinaceum ookinetes blocked the infection of aedes aegypti mosquitoes. the antibody did not block the development of zygotes to ookinetes in vitro. development of ookinetes to oocysts in the mosquito was blocked to the same extent whether zygotes grew to ookinetes in the presence of mab c5 or the antibody was added after the ookinetes had reached full development. when ookinetes developed in ...19912009919
prevalence of babesia antibody in a selected blood donor population.human babesiosis, a parasitic disease transmitted by the tick, ixodes dammini, was confined previously to limited areas of the northeastern united states. it is a rare but potentially life-threatening complication of transfusion. red cells and platelets prepared from asymptomatic donors have been implicated in transfusion-transmitted cases. more cases of babesiosis are being reported as the range of the vector expands in the united states. blood donors from an endemic area were tested for antibo ...19883341068
effects on in vitro growth of babesia microti by cells and serum from b. microti and schistosoma mansoni infected mice. 19883151427
effect of carrier erythrocytes containing inositol hexaphosphate on babesia microti infection.erythrocytes containing inositol hexaphosphate (ihp) were administered to mice. mice were then challenged with babesia microti. mice receiving ihp carrier erythrocytes had significantly lower percentages of parasitaemias on days 3, 5 and 7 after infection. carrier erythrocytes containing ihp have altered p50 oxygen values. thus, carrier erythrocytes containing ihp may be useful in treating naive animals before transporting into areas endemic for babesiosis.19883194600
the prevalence and significance of borrelia burgdorferi in the urine of feral reservoir borrelia burgdorferi were isolated from the blood and/or urine of white-footed mice (peromyscus leucopus) collected on shelter island, new york, in 1984 and 1985. prevalence of spirochetes in urine was consistently higher than in blood or both fluids simultaneously. spirochetes remained viable for 18-24 hours in urine and were maintained in culture for one week. mice removed from the field were spirocheturic for at least 13 months. one spirocheturic mouse developed spirochetemia one month a ...19863577491
isolation and characterization of a gene associated with a virulent strain of babesia microti.babesia microti genomic dna was purified from parasitized murine erythrocytes, digested with mung bean nuclease and used to construct an expression library in lambda gt11. polyspecific antisera from mice infected with virulent b. microti organisms (atcc30221) were used to screen the genomic library for genes encoding major immunogens. high titer antisera selected a recombinant phage, bm13, containing 3.3 kb of b. microti dna. hybridization analysis confirmed the parasite origin of the clone; aff ...19902362602
reduced parasitemia observed with erythrocytes containing inositol hexaphosphate.chemicals entrapped in erythrocytes by hypotonic hemolysis can be assessed for possible antiparasitic activity both in vivo and in vitro, regardless of whether they are able to diffuse into erythrocytes readily. inositol hexaphosphate, a highly charged compound, produced a dramatic lowering of the percentage of cells infected by babesia microti in vivo and both b. microti and plasmodium falciparum in vitro. several possible mechanisms for this observation are discussed.19883364957
the contribution of b-cell proliferation to spleen enlargement in babesia microti-infected mice.flow cytofluorimetric analysis showed that b-cell proliferation makes a major contribution to the enlargement and increased cellularity of the spleen, which are characteristic of babesia microti infections in mice. expansion of the b-cell population was accompanied by modulation of the cell surface, which affected most b lymphocytes, and which was detected as a reduction in the density of surface immunoglobulin. this effect was noted as early as day 7, shortly after the appearance of parasites i ...19873493207
transfusion-transmitted babesiosis: a case report from a new endemic area.the seventh documented case of babesiosis transmitted by transfusion is reported. both the donor and the recipient are residents of connecticut, where the presence of endemic babesiosis has only recently been established. as the range of babesia microti, and its vector the ixodes dammini tick, continues to expand, clinicians and blood bank directors should be aware that cases of transfusion-transmitted babesiosis may occur in newly endemic areas.19912021001
immunity to babesia microti in male mice selected as resistant or susceptible to nematospiroides dubius. 19883417381
comparative prevalence of babesia microti and borrelia burgdorferi in four populations of ixodes dammini in eastern massachusetts.we determined the prevalence of babesia microti and borrelia burgdorferi in four populations of ixodes dammini in eastern massachusetts. the feulgen's reaction was more sensitive than the giemsa method for detecting salivarian babesia. a combination of darkfield and direct-fluorescent-antibody examination proved more sensitive than either method alone for detecting spirochetal infection. the prevalence of spirochetes was greater than the prevalence of babesia in each of the tick populations stud ...19862430433
heterologous synergistic interactions in concurrent experimental infection in the mouse with schistosoma mansoni, echinostoma revolutum, plasmodium yoelii, babesia microti, and trypanosoma brucei.primary infections with plasmodium yoelii and echinostoma revolutum in the mouse induced a significant increase in the heterologous schistosoma mansoni challenge worm establishment, whereas s. mansoni worm establishment remained unaffected by primary infections with trypanosoma brucei and babesia microti. concurrent infection in the mouse with p. yoelii or t. brucei, but not with b. microti, blocked the resistance to homologous e. revolutum challenge infection, and primary p. yoelii and t. bruce ...19883143108
indirect immunofluorescence test for human babesia microti infection: antigenic indirect immunofluorescence (iif) test was performed with human sera to detect cross-reactivity of babesia microti antibodies with other species of babesia parasites, with other blood and tissue parasites, and with various tick-borne organisms. antisera to b. microti cross reacted with other babesia species, but at lower dilutions than with the homologous antigens, and occurred most often during the acute phase of the disease. cross-reactions with antibodies to malaria, colorado tick fever, a ...19862429568
the proliferative response of mouse lymphoid tissues during infections with babesia microti or babesia rodhaini. 19873583545
intensity and duration of borrelia burgdorferi and babesia microti infectivity in rodent hosts. 19883170076
babesia microti: prolonged survival of salavarian piroplasms in nymphal ixodes dammini.we determined how long babesia microti survive in the salivary glands of nymphal ixodes dammini. of those ticks held at 21 c, the proportion with demonstrable piroplasms decreased from 95%, prior to 20 weeks post-larval-feeding (p-l-f), to less than 80% at 42 weeks p-l-f. similarly, the number of infected acini decreased significantly. nymphal i. dammini were kept alive for as long as 1 year, by transferring them to 4 c, at 20 weeks p-l-f. the proportion of infected ticks at 52 weeks p-l-f was l ...19873678441
borrelia burgdorferi and babesia microti: efficiency of transmission from reservoirs to vector ticks (ixodes dammini).in endemic regions, peromyscus leucopus, the mouse reservoir of the lyme disease spirochete (borrelia burgdorferi) and the piroplasm causing human babesiosis (babesia microti), is nearly universally infected with both agents. paradoxically, spirochetal infection is nearly twice as prevalent as is babesial infection in populations of field-collected nymphal ixodes dammini, the tick vector. in the laboratory, a similarly disproportionate rate of infection was observed among nymphal ticks, feeding ...19902295326
suppression of babesia microti infection in mice concurrently infected with fasciola hepatica.blood cell parasitaemia of babesia microti and the associated haematological changes were examined in mice harbouring patent fasciola hepatica infections and in fluke-free control mice. b. microti parasitaemia was markedly suppressed in mice harbouring primary 7-week f. hepatica infections, as reflected in a reduction in the percentage of erythrocytes parasitised and in the incidence of multiple b. microti infections in the red cells. this suppression was accompanied by an annulment of b. microt ...19853992864
simultaneous transmission of borrelia burgdorferi and babesia microti by individual nymphal ixodes dammini ticks.nymphal ixodes dammini ticks, selected from a group of ticks in which 22 of 31 (71%) contained dual borrelia burgdorferi and babesia microti infections, simultaneously transmitted b. burgdorferi and b. microti to 4 of 7 (57%) hamsters exposed to individual ticks.19873667924
seasonal variation of transmission risk of lyme disease and human babesiosis.the seasonal host-seeking pattern of nymphal ixodes dammini infected with babesia microti or borrelia burgdorferi was determined on nantucket island, massachusetts, during 1985. the peak period of host-seeking by infected nymphal i. dammini occurred in may and june. on a per person-hour basis, the number of infected ticks collected reached a maximum in may (babesia = 17.3; borrelia = 16.2). the number of infected ticks remained high in june, but decreased notably in july, august, and september. ...19873687924
pathology of experimental babesia microti infection in the syrian hamster.pathologic changes produced after 4 weeks of infection by babesia microti in syrian hamsters are described and compared to babesiosis of humans. following intraperitoneal inoculation, both intravascular and extravascular hemolysis developed. up to 70% of red blood cells were parasitized. the principal morphologic abnormalities were an increase in extramedullary hematopoiesis and hyperplasia of the mononuclear phagocytic cells of the red pulp manifested grossly as splenomegaly, marked renal tubul ...19873695401
antibody levels in mice infected with babesia microti. 19704099405
ixodes dammini (acari: ixodidae) in maryland, usa, and a preliminary survey for babesia microti. 19863735353
lymphocyte migration in murine malaria during the primary patent parasitaemia of plasmodium chabaudi infections.inoculation of adult c57/bc mice with 10(6) red cells infected with plasmodium chabaudi induces an acute primary parasitaemia peaking around the 8th or 9th day and lasting 10-14 days. concomitantly, the spleen enlarges to reach 6-7 times its normal weight by the 11th day. the major component of this increase is between day 9 and 11, due primarily to an increase in erythropoietic cells in the red pulp. although initially the white pulp increases in size, by day 11 it shows partial lymphocyte depl ...19873498567
prevalence of borrelia burgdorferi and babesia microti in mice on islands inhabited by white-tailed deer.borrelia burgdorferi and babesia microti were isolated from 35 of 51 white-footed mice (peromyscus leucopus) and meadow voles (microtus pennsylvanicus) captured on two narragansett bay, r.i., islands inhabited by deer, the principal host for the adult stages of the vector tick, ixodes dammini. immature ticks parasitized mice from both islands. from 105 mice captured on four other islands not inhabited by deer neither pathogen was isolated, nor were i. dammini found.19873555339
isoenzyme analysis of babesia microti infections in humans.we used high-resolution polyacrylamide gradient gel electrophoresis (pgge) to separate four babesial enzymes to aid in the identification of two babesia microti isolates established in hamsters. the isolates were compared to two different hamsters passages of the "gray" strain. all isoenzymes patterns from the two isolates and the "gray" strain were similar except glucose phosphate isomerase (gpi) from one of the "gray" strain passages. it showed a polymorphic gpi pattern as opposed to a monomor ...19863735151
[light and electron microscopy studies of the developmental cycle and effect of pentamidine on the morphology of intra-erythrocyte stages of babesia microti]. 19863536409
babesiosis in wisconsin. a new focus of disease transmission.a confirmed case of human babesiosis was identified in august 1983 in a 54-year-old asplenic wisconsin resident. babesia microti was identified as the causative agent by blood smear morphology and hamster inoculation techniques. the patient's wife had clinically confirmed lyme disease in 1981 and had serologic evidence (immunofluorescent antibody to a b microti titer of 1:1,024) of recent babesia infection in august 1983. mice (peromyscus species) trapped on the patients' property and elsewhere ...19853886942
serological evidence for simultaneous occurrences of lyme disease and babesiosis.babesia microti and borrelia burgdorferi, the spirochetal agent of lyme disease, are both transmitted by the tick ixodes dammini. serological evidence has shown that 54% of the patients with babesiosis tested have igg and igm antibodies to the spirochete causing lyme disease. likewise, 66% of randomly selected patients with lyme disease from geographic areas endemic for both diseases, but not from areas where babesiosis does not occur, also have igm and igg antibodies to b. microti. antigenic cr ...19854031555
development of babesia microti sporozoites in adult ixodes dammini. 19863744675
the stability of babesia microti infections after prolonged passage, a comparison with a recently isolated strain. 19853914864
concurrent borrelia burgdorferi and babesia microti infection in nymphal ixodes dammini.ixodes dammini nymphs were examined for evidence of concurrent infection with borrelia burgdorferi and babesia microti. a total of 19 nymphs (18.6%) from nantucket island were simultaneously infected, as were 24 nymphs (8.2%) from naushon island. these observations are consistent with a common reservoir host for both i. dammini-transmitted pathogens.19863760136
the effect of mitomycin c treatment of infected erythrocytes on infection with babesia microti and babesia rodhaini in mice. 19853920167
suppression of babesia microti infection in mice concurrently infected with schistosoma mansoni. 19853933288
enhancement and prolongation of babesia microti infections in mice infected with oncogenic viruses. 19724627209
the "gray" strain of babesia microti from a human case established in laboratory animals. 19704994129
fatal pancarditis in a patient with coexistent lyme disease and babesiosis. demonstration of spirochetes in the myocardium.a 66-year-old man developed fever, chills, myalgias, three erythematous skin lesions, and transient left eyelid lag. because of persistent fever, he was hospitalized 4 weeks after the onset of disease; a peripheral blood smear showed babesia microti in 3% of his erythrocytes. eighteen hours later, he died unexpectedly. autopsy showed pancarditis with a diffuse lymphoplasmacytic infiltrate, and spirochetes were found in the myocardium. antibody titers to both the lyme disease spirochete borrelia ...19854040723
delayed-type hypersensitivity to babesia microti-infected erythrocytes in mice.strong delayed-type hypersensitivity (dth) to babesia microti was elicited when intraerythrocytic parasites (iep) were inoculated subcutaneously into the flank of normal mice 6 to 14 days before challenge in the ipsilateral footpad with 10(8) iep. intraperitoneal or intravenous administration of antigen did not sensitize mice for dth. when challenge was given 21 days after immunization, the response was approximately half of the maximum and then rose again slowly over the next 3 weeks to levels ...19863757050
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