Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
|---|
| surveillance of human ehrlichiosis in the united states: 1988. | 1990 | 2378462 | |
| characterization and antigenicity of recombinant major antigens of ehrlichia risticii. | 1990 | 2378467 | |
| gene amplification by polymerase chain reaction for detection of ehrlichia risticii dna in potomac horse fever. | 1990 | 2378479 | |
| simultaneous infection with an ehrlichia and borrelia burgdorferi in a child. | 1990 | 2378481 | |
| studies on experimental jembrana disease in bali cattle. ii. clinical signs and haematological changes. | the clinical and haematological changes which occurred in 18 bali cattle (bos javanicus) experimentally infected with jembrana disease are described. the major clinical signs were an elevated rectal body temperature persisting for 7 days (range 5 to 12 days), lethargy, anorexia, enlargement of the superficial lymph nodes, a mild ocular and nasal discharge, diarrhoea with blood in the faeces and pallor of the mucous membranes. not all of these changes occurred in all affected cattle. the major ha ... | 1990 | 2394847 |
| histologic and immunochemical study of the pathogenesis of heartwater (cowdria ruminantium infection) in goats and mice. | eleven adult goats and 32 adult outbred mice were inoculated iv with cowdria ruminantium-infected blood (kwanyanga isolate), monitored clinically, then serially euthanatized. predominant clinical signs of disease in goats were depression, head tremors, seizures, and dyspnea. in mice, dyspnea and depression were the only clinical signs of disease noticed. tissues were examined histologically and immunohistochemically for c ruminantium colonies or antigen. in goats, c ruminantium was detected only ... | 1990 | 2396797 |
| infection rates with cowdria ruminantium of nymphs and adults of the bont tick amblyomma hebraeum collected in the field in zimbabwe. | cowdria ruminantium (heatwater) infection rates of field populations of the bont tick, amblyomma hebraeum, were determined at two locations in the southern lowveld of zimbabwe. at mbizi quarantine station, unfed adult males and females, and nymphs were collected at intervals over a 2-year period using traps. at lemco ranch, engorged nymphs were collected on three occasions from weaner calves and allowed to moult to adults. the unfed ticks were fed in small pools on heartwater-susceptible sheep, ... | 1990 | 2399648 |
| ehrlichia of potomac horse fever identified with a silver stain. | 1986 | 2428158 | |
| heartwater. the morphology of cowdria ruminantium and its staining characteristics in the vertebrate host and in vitro. | the morphology of cowdria ruminantium is described and its staining characteristics in the vertebrate host and in vitro are summarized. morphologically, the organisms are characterized in the cytoplasm of endothelial cells, macrophages and reticulo-endothelial cells. based on the morphology of the internal structure of the organisms, elementary (electron-dense), intermediate and reticulate bodies are identified. each organism is surrounded by a double membrane and a "capsule" is evident around a ... | 1987 | 2452396 |
| distinctive staining of colonies of cowdria ruminantium in midguts of amblyomma hebraeum. | mallory's phloxine-methylene blue stain was used to differentiate colonies of cowdria ruminantium in midgut epithelial cells of nymphal amblyomma hebraeum that had been infected as larvae. gut tissues were collected from nymphs that had fed on a susceptible sheep and were fixed in formol-saline on the day of repletion. paraffin sections, 3-4 micron thick, were then stained and this rendered colonies and cell nuclei densely blue against a uniformly pink background of tick tissues. colonies were e ... | 1987 | 2452397 |
| detection of ehrlichia risticii using an avidin-biotin-immunoperoxidase staining system. | an indirect immunoperoxidase procedure using a specific anti-ehrlichia risticii monoclonal antibody and an avidin-biotin-peroxidase staining method was used to detect e. risticii antigen in infected p388d1 murine monocytes. several different methods of cytological fixation were used, including acetone (15 min), 95% ethanol (15 min), bouin's fixative (5 hr), and 10% buffered neutral formalin (24 hr). the e. risticii organisms were labeled effectively and identified in cells fixed with acetone and ... | 1989 | 2484933 |
| [ticks and hemoparasitoses of livestock in senegal. iii. the northern sudan area]. | the authors describe the results of a study on ticks and hemoparasitoses of cattle and small ruminants in the senegalese north-sudanian area. for 15 months, 40 bovine, 40 sheep and 40 goats received a routine dipping treatment, aimed at the determination of the tick population dynamics together with an accurate localization of the preferential sites for the different species. the following parasites were collected from the animals: hyalomma marginatum rufipes, h. truncatum, rhipicephalus lunulat ... | 1989 | 2485548 |
| effect of antibiotics on clinical, pathologic and immunologic responses in murine potomac horse fever: protective effects of doxycycline. | effects of three antibiotics on clinical, pathologic and immunologic responses in murine potomac horse fever caused by ehrlichia risticii infection were examined. when antibiotics were given after the development of clinical signs, antibiotics ranked in the order of reducing clinical signs and in preventing body weight loss and an intestinal enlargement were doxycycline, demeclocycline and rifampin. infected mice treated with doxycycline and demeclocycline developed greater splenomegaly than rif ... | 1989 | 2497577 |
| a serological survey of ehrlichia canis, ehrlichia equi, rickettsia rickettsii, and borrelia burgdorferi in dogs in oklahoma. | serum samples from 259 dogs were tested for antibodies to ehrlichia canis, ehrlichia equi, rickettsia rickettsii, and borrelia burgdorferi using the indirect fluorescent antibody test. the sera were obtained from submissions to the oklahoma animal disease diagnostic laboratory during a 14-month period from june 1986 through july 1987. the rate for positive antibody titers to e. canis was 53%, to e. equi was 33%, to r. rickettsii was 38%, and to b. burgdorferi was 18%. higher percentages of sera ... | 1989 | 2518693 |
| effect of tick-borne fever (ehrlichia phagocytophila) and trypanosomiasis (trypanosoma brucei 1066) on the pharmacokinetics of sulfadimidine and its metabolites in goats. | the effect of tick-borne fever (tbf) and trypanosomiasis (tbr) on the plasma disposition of sulfadimidine (sdd) in goats was studied after iv administration of 20 and 200 mg/kg of body weight. in each group of six goats, the plasma disappearance curves showed four animals with rapid and two with slow sdd elimination. it is likely that this difference is determined by oxidative rather than acetylation phenotype. in all goats administered 20 mg/kg, half-life increased with tbf but not with tbr. vd ... | 1989 | 2566460 |
| rocky mountain spotted fever. | 1989 | 2585382 | |
| focus of human parasitism by the brown dog tick, rhipicephalus sanguineus (acari: ixodidae). | throughout most of its range, the brown dog tick, rhipicephalus sanguineus (latreille), prefers dogs as a host, but human bites occasionally occur in the mediterranean region and central america; historically, this species has rarely bitten humans in the united states. a focus of 15 human bite cases by this tick is reported from four air force bases located within 200 miles of each other in north central texas and southwestern oklahoma. the sudden appearance of numerous documented bite cases ind ... | 1989 | 2585458 |
| feline anaemia associated with ehrlichia-like bodies in three domestic short-haired cats. | three domestic short-haired cats with a history of anorexia and loss of body condition had high rectal temperatures, and a normocytic, normochromic anaemia. two of them were also dyspnoeic, and thoracic radiographs revealed a diffuse, unstructured increase in radio-opacity involving all the lung lobes. examination of giemsa-stained blood smears and culture of blood monocytes revealed purplish-staining intracytoplasmic inclusions, in monocytes and lymphocytes, which occurred either singly or in a ... | 1989 | 2588453 |
| the role of males of the bont tick (amblyomma hebraeum) in the transmission of cowdria ruminantium (heartwater). | the role of males of the bont tick (amblyomma hebraeum) in the transmission of cowdria ruminantium (heartwater) was investigated. transstadial (nymph to adult) and intrastadial transmission were demonstrated. males transferred from live or dead hosts to live hosts were shown to transmit c. ruminantium repeatedly. it was concluded that male transmission is of importance in the epidemiology of heartwater. | 1989 | 2588467 |
| human ehrlichiosis associated with cerebrospinal fluid pleocytosis: a case report. | 1989 | 2589403 | |
| ehrlichiosis in a dog with seizures and nonregenerative anemia. | ehrlichia canis infection was diagnosed in a dog with a history of seizures and nonregenerative anemia. serologic titer to e canis was greater than 1:100. evaluation of csf revealed a high cell count, high protein concentration, and a positive pandy test result. several mononuclear leukocytes in the csf contained e canis morulae. central nervous system lesions are commonly found on postmortem examination of animals with ehrlichiosis, although clinical reports of neurologic signs attributable to ... | 1989 | 2599963 |
| the carrier status of sheep, cattle and african buffalo recovered from heartwater. | sheep, cattle and the african buffalo (syncerus caffer) were shown to remain carriers of heart-water (caused by cowdria ruminantium) for long periods after recovery; 223, 246 and 161 days, respectively. transmission was achieved using adults of the southern african bont tick (amblyomma hebraeum) that had fed as nymphs on recovered animals. our findings differ from those of other workers who attempted transmission using nymphs that had fed as larvae on recovered animals or with blood from recover ... | 1989 | 2617830 |
| monoclonal antibody-mediated, immunodiagnostic competitive enzyme-linked immunosorbent assay for equine monocytic ehrlichiosis. | competitive enzyme-linked immunosorbent assay (celisa), mediated by a monoclonal antibody designated hybi, was developed for the diagnosis of equine monocytic ehrlichiosis. inhibition of binding of hybi by the horse antibodies to ehrlichia risticii was optimum at dilutions of 1:20 for serum and 1:10,000 for hybi. mean optical densities (ods) of positive and negative sera were 0.158 and 0.855, respectively. a comparison of ods obtained by celisa and indirect enzyme-linked immunosorbent assay (eli ... | 1989 | 2643624 |
| ehrlichia canis: a tick-borne rickettsial-like infection in humans living in the southeastern united states. | during the past two years, sporadic cases of a rickettsial-like illness were reported in humans living in the southeastern united states. the illness was serologically similar to ehrlichia canis infections in dogs. it resembled spotless rocky mountain spotted fever but was differentiated from this infection serologically with acute and convalescent sera showing increasing titers to ehrlichia canis. e. canis infection should be suspected in patients with fever, headache, malaise, myalgia, gastroi ... | 1989 | 2643878 |
| protection of goats against caribbean and african heartwater isolates by the ball 3 heartwater vaccine. | two groups of castrated male adult goats (three goats/group) were infected intravenously with the ball 3 vaccine strain of cowdria ruminantium and treated with long-acting oxytetracycline at the onset of clinical disease 10 days later. five weeks post-vaccination one group was challenged with a caribbean isolate (gardel) and the other group with a west african isolate (mali) of c. ruminantium. non-vaccinated controls infected with either the gardel or mali isolate died. all of the vaccinated ani ... | 1989 | 2665252 |
| prevention of potomac horse fever. | 1989 | 2666021 | |
| ehrlichiosis--"spotless spotted fever". | ehrlichia canis, a canine rickettsia, produces an acute infection in humans characterized by thrombocytopenia, leukopenia, and anemia. patients should be closely questioned and examined for tick bites. rash is not prominent, leading to the interesting if somewhat inaccurate label of "spotless spotted fever." the diagnosis is made by clinical presentation, absence of positive lyme disease or rocky mounted spotted fever (rmsf) serology, and positive e. canis titers. tetracyclines are preferred tre ... | 1989 | 2668039 |
| white-footed mice: tick burdens and role in the epizootiology of potomac horse fever in maryland. | one hundred ten white-footed mice (peromyscus leucopus) were captured on horse farms in south-central maryland, examined for ticks, and tested for specific antibodies to ehrlichia risticii, the causative agent of potomac horse fever. peromyscus leucopus were consistently infested with immature american dog ticks (dermacentor variabilis), with monthly prevalences as high as 80%. sera from all 97 p. leucopus tested for antibodies to e. risticii were negative. this indicates that p. leucopus is not ... | 1989 | 2668569 |
| human ehrlichiosis. | ehrlichiosis is one of the latest tick-borne illnesses to be reported in humans. the authors describe two cases of this rickettsial disease that were apparently acquired in missouri. they discuss diagnosis and treatment. | 1989 | 2677657 |
| monthly prevalence (in 1986) of antibody titers against equine monocytic ehrlichiosis in apparently healthy horses in illinois. | the seroprevalence and seasonal trend of antibody titers against equine monocytic ehrlichiosis (potomac horse fever) were determined in apparently healthy horses in selected areas of illinois in 1986. sera from 1,367 horses (6 months to 29 years old) were evaluated for the presence of antibodies against ehrlichia risticii with indirect immunofluorescence. the majority (88%) of the horses were thoroughbred or standardbred racehorses. the number of horses with antibodies against e risticii was 229 ... | 1989 | 2694868 |
| serotypes in cowdria ruminantium and their relationship with ehrlichia phagocytophila determined by immunofluorescence. | two tick-borne rickettsial pathogens of ruminants, cowdria ruminantium (causative agent of heartwater disease) and ehrlichia phagocytophila (causative agent of tick-borne fever), were successfully cultivated in caprine or ovine neutrophilic granulocytes. infected cultures were subsequently used as antigens in the indirect fluorescent antibody test. low-level bilateral serological cross-reactions could be detected between cowdria and ehrlichia. in addition, comparison of five cowdria stocks using ... | 1989 | 2696198 |
| a mouse lethal dose assay for detection and titration of cowdria ruminantium (kwanyanga strain) in goats and ticks. | a mouse lethal dose assay was used to detect a mouse pathogenic strain (kwanyanga) of cowdria ruminantium, the etiological agent of heartwater in goats and ticks. the titer of the rickettsial organisms in goat blood was directly related to the febrile response of the goat and the rickettsia were undetectable after the fever subsided. the maximum rickettsial titer in goat blood was 10(3) mouse ld50 ml-1. cowdria-infected goat blood was shown to retain infectivity when held on ice for up to 2 h, b ... | 1989 | 2705290 |
| lack of co-transmission of rickettsia conorii and ehrlichia canis in human beings in the south of france. | ehrlichia canis is the agent of canine ehrlichiosis, commonly known as canine tropical pancytopenia. this canine disease is frequent in our area, as is mediterranean spotted fever in humans. recently a few cases of human ehrlichiosis have been described in the usa. the supposed vector of both diseases is rhipicephalus sanguineus. in order to evaluate the co-transmission of these two diseases, we selected 498 human sera positive for r. conorii and tested them for ehrlichia canis. none of them wer ... | 1989 | 2707389 |
| development of a prophylactic regime using long-acting tetracycline for the control of redwater and heartwater in susceptible cattle moved into an endemic area. | thirty young crossbred steers were purchased from a tick-borne disease-free farm in south africa, shown to be serologically negative to babesia bigemina/bovis and cowdria ruminantium, and moved to an experimental farm where babesiosis and heartwater were known to be endemic. the animals were allowed to graze as a herd on tick-infested areas of the farm for 90 days from the beginning of april but were separated into three groups of 10 for treatment. one group received a prophylactic regime of two ... | 1989 | 2711456 |
| infection with ehrlichia canis in a child. | 1989 | 2715894 | |
| ehrlichia in tennessee. | 1989 | 2717999 | |
| aseptic meningitis associated with ehrlichia canis infection. | 1989 | 2726324 | |
| the isolation of nucleic acid sequences specific for cowdria ruminantium. | screening of a genomic library of cowdria ruminantium has yielded twelve clones hybridizing to cowdria dna. these clones should be suitable for development into dna probes specific for this organism. | 1989 | 2748132 |
| transmission is unsolved mystery of equine monocytic ehrlichiosis. | 1989 | 2753790 | |
| phylogenetic diversity of the rickettsiae. | small subunit rrna sequences have been determined for representative strains of six species of the family rickettsiaceae: rickettsia rickettsii, rickettsia prowazekii, rickettsia typhi, coxiella burnetii, ehrlichia risticii, and wolbachia persica. the relationships among these sequences and those of other eubacteria show that all members of the family rickettsiaceae belong to the so-called purple bacterial phylum. the three representatives of the genus rickettsia form a tight monophyletic cluste ... | 1989 | 2753854 |
| ehrlichia canis infection in a child. | 1989 | 2771561 | |
| suspected ehrlichiosis in a gelding in wales. | 1989 | 2773204 | |
| presence of cytoecetes phagocytophila in an atypical disease of cattle in spain. | 1989 | 2773206 | |
| epidemiology of potomac horse fever: an investigation into the possible role of non-equine mammals. | a serological study of antibodies to ehrlichia risticii was carried out on 10 species of wild and domestic mammals found on or near 21 horse farms in an area of the usa in which potomac horse fever is endemic. no antibodies were found in 133 peridomestic rodents (norway rats and house mice), nor in 108 wild rodents (white-footed mice and meadow voles) captured on farms. three of the six domestic animal species examined, cats, pigs and a goat, showed serological evidence of exposure to e risticii ... | 1989 | 2773237 |
| production and characterization of monoclonal antibodies to ehrlichia risticii. | hybridomas producing monoclonal antibodies to ehrlichia risticii were developed to provide a means of molecular investigation of the biochemical and immunopathologic characteristics of the organism. all of 6 stable monoclonal antibodies obtained were igg isotypes. the ascitic fluid titers induced by the hybridomas ranged from 10(2) to 10(7). competitive binding experiments conducted by elisa and binding of labeled protein a to antigen-antibody complexes indicated competition among monoclonal ant ... | 1989 | 2774338 |
| antibody response to ehrlichia risticii and antibody reactivity to the component antigens in horses with induced potomac horse fever. | the antibody response and the antibody reactivity to component antigens of ehrlichia risticii were studied in horses with induced potomac horse fever. these horses had no detectable antibodies to e. risticii in their preinoculation (pri) sera by indirect fluorescent-antibody assay and enzyme-linked immunosorbent assay (elisa). all the horses exhibited typical disease features following experimental infection and responded with specific antibodies, as measured by elisa and indirect fluorescent-an ... | 1989 | 2777369 |
| identification of an immunodominant antigenically conserved 32-kilodalton protein from cowdria ruminantium. | western blotting (immunoblotting) of cowdria ruminantium antigens with goat or mouse antiserum identified a periodate-resistant, proteinase k-sensitive immunodominant antigen of 32,000 daltons. this protein, designated cr32, could be demonstrated in goat choroid plexus infected with one of two different cowdria stocks. antisera against nine different cowdria stocks from africa and the caribbean region recognized cr32, which indicates that this protein contains conserved antigenic determinants. | 1989 | 2777383 |
| concurrent positive serology for ehrlichiosis and lyme disease. | 1989 | 2794568 | |
| role of blackflies in the epidemiology of potomac horse fever. | 1989 | 2800259 | |
| human ehrlichiosis: prospective active surveillance in febrile hospitalized patients. | between 1 april 1987 and 30 september 1988 prospective active surveillance of human ehrlichiosis was conducted among febrile patients hospitalized in southeast georgia. if disease of the immune system, bacterial infection, pneumonia, or surgical illness was documented by the end of the first full day of hospitalization, the patient was excluded. of 75 patients enrolled in the study, 8 (10.7%) had a fourfold rise or fall in titer to ehrlichia canis (case-patients). the rate was 5.3 cases/100,000 ... | 1989 | 2809255 |
| immunity of tick-exposed seronegative and seropositive small stock challenged with two stocks of cowdria ruminantium. | nineteen per cent and 32% of serologically positive sheep and goats in heartwater endemic areas of the republic of south africa were susceptible to challenge with, respectively, the ball 3 and welgevonden stocks of cowdria ruminantium. there was good correlation between the results of the indirect fluorescent antibody test and immunity, since without exception all the seronegative animals reacted when they were challenged. the fact that only 74% of the seropositive sheep and goats were immune to ... | 1989 | 2812702 |
| the heterogenicity of cowdria ruminantium stocks: cross-immunity and serology in sheep and pathogenicity to mice. | ten stocks of cowdria ruminantium (ball 3, breed, comoro, germishuys, kümm, kwanyanga, mali, mara, nonile and welgevonden) were compared from a cross-immunity, serological and mouse pathogenicity point of view. they were found to differ in varying degrees. except for the ball 3, comoro and germishuys stocks that were similar but not identical, there was no pattern in the antigenic diversity of the 10 stocks. the welgevonden stock emerged as the stock that elicits an immunity against most of the ... | 1989 | 2812704 |
| horse-baited insect trap and mobile insect sorting table used in a disease vector identification study. | a horse-baited trap and a mobile insect sorting table were used to conduct an arthropod survey for potential vectors of potomac horse fever in southern maryland and northern virginia. the trap and table worked effectively for the live collection and sorting of haemophagous diptera such as: simulium spp., stomoxys calcitrans, musca autumnalis, tabanus spp. and chrysops spp. during the diurnal collections periods, and culicoides spp. during the crepuscular periods. the trap was not as convenient f ... | 1988 | 2906356 |
| pheromone-mediation of host-selection in bont ticks (amblyomma hebraeum koch). | the bont tick, amblyomma hebraeum, is the principal vector to southern african ruminants of heartwater (cowdria ruminantium infection). the role of feeding male ticks, which emit an aggregation-attachment pheromone, in attracting unfed ticks to cattle was investigated. calves infested with feeding male ticks were more attractive to unfed adult ticks than were uninfested calves. the presence of the pheromone on previously infested cattle apparently allows unfed ticks to discriminate between hosts ... | 1989 | 2911745 |
| an outbreak of ehrlichiosis in members of an army reserve unit exposed to ticks. | an outbreak of unexplained illness occurred in members of an army reserve unit after field training in an area of new jersey endemic for lyme disease. nine (12%) of the 74 who attended the exercise had serological evidence of ehrlichia infection, defined as a single rise in titer of antibody to ehrlichia canis greater than or equal to 1:160 four weeks after training. two reservists with early serum samples had documented seroconversion, defined by a four-fold or greater increase in titer of anti ... | 1989 | 2915168 |
| human ehrlichiosis in oklahoma. | 1989 | 2915171 | |
| ehrlichiosis. | 1989 | 2921197 | |
| energy metabolism of monocytic ehrlichia. | we investigated if the monocytic ehrlichia are totally dependent on their host cells for energy, or, as rickettsia, are capable of some atp synthesis in vitro. the miyayama strain of ehrlichia sennetsu and the maryland and illinois strains of ehrlichia risticii were cultivated in a mouse macrophage cell line, separated from host cell constituents by procedures that included renografin or percoll gradient centrifugation, and tested after cryopreservation. cells incubated without a metabolizing su ... | 1989 | 2922404 |
| [what is your diagnosis? which course of action do you propose?]. | 1989 | 2928751 | |
| ehrlichiosis: a cause of bone marrow hypoplasia in humans. | 1989 | 2929590 | |
| observations on mouse-infective stocks of cowdria ruminantium: attempts to demonstrate persistence of the organism in mice immune to the kwanyanga stock. | mice immunised against the kwanyanga stock of cowdria ruminantium by infection and treated with oxytetracycline proved immune to challenge on day 40 and also to a second challenge on day 125 after infection. treatment with the experimental dithiosemicarbazone gloxazone on days 59 and 73 did not abolish immunity to challenge on day 125. no persistence of the organism in immune mice that had been challenged on day 40 could be demonstrated by subinoculating blood and liver homogenate on day 126. th ... | 1987 | 2950579 |
| adaptation of ehrlichia sennetsu to canine blood monocytes: preliminary structural and serological studies with cell culture-derived ehrlichia sennetsu. | ehrlichia sennetsu, the causative agent of human sennetsu rickettsiosis, was successfully propagated in primary canine blood monocyte cultures. the growth cycle of this organism appears to be similar to that of ehrlichia canis. the antigen derived from our e. sennetsu cultures was used to develop an indirect fluorescent antibody test for detection and titration of serum antibodies to the organism. using this test system, we found that five human serum samples obtained from patients clinically di ... | 1985 | 2985504 |
| isolation of cowdria ruminantium by means of percoll density gradient centrifugation and detection by an enzyme-linked immunosorbent assay. | the isolation of cowdria ruminantium by means of percoll density gradient centrifugation permits the recovery of partially purified viable populations of the organism possessing distinctly different densities. these conclusions are based upon results of analyses of density fractions by intravenous inoculation into sheep, protein determination, electron microscopy and enzyme-linked immunosorbent assay. morphological differences were observed in the density fractions obtained from infected brain t ... | 1986 | 3014417 |
| human infection with ehrlichia canis, a leukocytic rickettsia. | 1987 | 3029590 | |
| colorado tick fever or ehrlichiosis. | 1987 | 3041059 | |
| [clinical and serological diagnosis of ehrlichiosis in dogs in switzerland]. | 1988 | 3047860 | |
| childhood infection caused by ehrlichia canis or a closely related organism. | 1988 | 3050859 | |
| susceptibility to heartwater of calves born to non-immune cows. | the resistance to artificial infection with cowdria ruminantium of calves born to cows fully susceptible to heartwater is no different from that of calves bred in heartwater endemic areas where the tick challenge is negligible to considerable. the sub-inoculation into mice of blood collected 14-26 days after infection proved the presence of the heartwater agent in the blood of 8 out of 10 calves with no other clinical signs than mild to moderate fever. the combined use of a mouse model and the i ... | 1988 | 3064021 |
| susceptibility of cats to infection with ehrlichia risticii, causative agent of equine monocytic ehrlichiosis. | eight adult cats were inoculated iv (n = 6) or sc (n = 2) with ehrlichia risticii-infected p388d1 (continuous murine macrophage) cells or with e risticii released from p388d1 cells. three additional cats were inoculated with organism-free p388d1 cultured monocytes, and 1 cat, which served as a medium control was inoculated with balanced salt solution. clinical signs of illness were observed in the iv inoculated cats from which e risticii was isolated. one cat developed intermittent diarrhea betw ... | 1988 | 3071194 |
| human ehrlichiosis--united states. | 1988 | 3129641 | |
| effect of equine ehrlichial colitis on the hemostatic system in ponies. | hemostatic function was determined in 10 ponies at various times after inoculation with ehrlichia risticii to determine whether equine ehrlichial colitis (eec) caused changes in the hemostatic system and to determine the prognostic value of hemostatic function tests during eec. mean platelet count; plasma fibrinogen, fibronectin, factor viii: coagulant, alpha 2-antiplasmin, and plasminogen values; and serum concentrations of fibrin/fibrinogen degradation products changed significantly (p less th ... | 1988 | 3138929 |
| in vitro susceptibilities of ehrlichia risticii to eight antibiotics. | inhibition of the proliferation of ehrlichia risticii cultured in murine macrophage p388d1 cells by eight antibiotics was evaluated by indirect fluorescent-antibody staining with an antiserum specific to e. risticii. there was a negative correlation between the percentage of infected cells and the log10 of the concentrations of all antibiotics examined. the ranks of the antibiotics in the order of 50% inhibitory concentrations (on a microgram-per-milliliter basis) after 48 h of exposure were as ... | 1988 | 3142345 |
| antibodies to ehrlichia canis, ehrlichia platys, and spotted fever group rickettsiae in louisiana dogs. | antibodies to ehrlichia canis, ehrlichia platys, and spotted fever group (sfg) rickettsiae were detected by indirect immunofluorescence in sera from 27 ill individually owned thrombocytopenic dogs (platelet concentrations less than 200,000 platelets/microliters) and 59 healthy kenneled dogs located in southern louisiana. platelet concentrations less than 100,000 platelets/microliters were detected in 63% of ill thrombocytopenic dogs and 6.8% of healthy kennel dogs. one ill thrombocytopenic dog h ... | 1988 | 3146636 |
| clinical, histopathological, and immunological responses of ponies to ehrlichia sennetsu and subsequent ehrlichia risticii challenge. | ehrlichia risticii has a close antigenic relationship to e. sennetsu. sera of ponies experimentally infected with e. risticii, the etiologic agent of potomac horse fever, consistently reacted with e. sennetsu, a human pathogen, in indirect fluorescent-antibody (ifa) testing, while human e. sennetsu convalescent serum reacted with e. risticii by ifa testing and immunoferritin labeling of cells infected in vitro. two ponies injected intravenously with live e. sennetsu did no develop clinical illne ... | 1988 | 3169993 |
| lack of lysosomal fusion with phagosomes containing ehrlichia risticii in p388d1 cells: abrogation of inhibition with oxytetracycline. | fusion of lysosomes with phagosomes containing ehrlichia risticii, an obligate intracellular parasite, was evaluated in p388d1 murine macrophagelike cells. lysosomes in cells ranging in infectivity from 30 to 70% were labeled cytochemically with acid phosphatase or via endocytosis of thorium dioxide or cationized ferritin to document phagosome-lysosome (p-l) fusion in untreated cells and cells treated with oxytetracycline. regardless of the marker used, p-l fusion was generally not observed in e ... | 1988 | 3182078 |
| substrate utilization by ehrlichia sennetsu and ehrlichia risticii separated from host constituents by renografin gradient centrifugation. | the in vitro metabolic activities of two monocytic species of ehrlichia were investigated. the miyayama strain of ehrlichia sennetsu and two strains of ehrlichia risticii, isolated in illinois and maryland, were cultivated in a p388d1 mouse macrophage cell line. the ehrlichia particles from heavily infected cultures were separated from host constituents by a renografin gradient centrifugation procedure modified from those employed for rickettsiae and chlamydiae. the metabolic activities of the i ... | 1988 | 3182726 |
| some pharmacokinetic data of aditoprim and trimethoprim in healthy and tick-borne fever infected dwarf goats. | aditoprim (ap) is a new dihydrofolate reductase inhibitor, which is structurally related to trimethoprim (tmp). the pharmacokinetics of ap (10 mg/kg) and tmp (20 mg/kg) were assessed in healthy dwarf goats. therapeutic efficacy against rickettsial infections was tested in tick-borne fever (tbf) infected goats. the animals were given tmp (n = 5) or ap (n = 5) by i.v. injection, and subsequently the drugs were administered orally (same groups, similar doses). finally, both groups were infected wit ... | 1988 | 3184252 |
| was bullis fever actually ehrlichiosis? | 1988 | 3184365 | |
| disease features in horses with induced equine monocytic ehrlichiosis (potomac horse fever). | fifty-five horses were inoculated iv and/or sc with materials containing ehrlichia risticii, ie, infected whole blood, buffy coat cells, or cell culture, to study clinical and hematologic features of equine monocytic ehrlichiosis (potomac horse fever). major clinical and hematologic features of induced e risticii infection were biphasic increase in rectal temperature with peak increases of 38.9 c and 39.3 c on postinoculation days (pid) 5 and 12, respectively; depression; anorexia; decreased wbc ... | 1988 | 3189992 |
| effect of tick-borne fever on liver and kidney function in dwarf-cross goats. | 1988 | 3203207 | |
| the significance of eperythrozoon ovis in ill-thrift in sheep in the eastern cape coastal areas of south africa. | ill-thrift in sheep in the coastal region of the eastern cape is described. it is shown to be a complex problem attributable to many causes, most of which can be eliminated by supplementary feeding, drenching, vaccination, dipping and management. however, studies on the aetiology of ill-thrift in young sheep indicate that arthropod-borne anaemia-producing pathogens are an important contributing factor, which cannot readily be diagnosed and controlled. experiments were conducted on various farms ... | 1988 | 3210217 |
| the presence of cowdria ruminantium antigen in various tissues of amblyomma hebraeum imagines as detected by an enzyme-linked immunosorbent assay. | investigation into the presence of c. ruminantium antigen, using an enzyme-linked immunosorbent assay (elisa) in various tick tissues and haemolymph of adult amblyomma hebraeum ticks revealed that the organism invades a number of body parts and can be demonstrated in a. hebraeum. in females, the gut, salivary glands, hypodermis and synganglion and in males, the salivary glands and gut showed the highest concentration. | 1988 | 3217097 |
| susceptibility of dogs to infection with ehrlichia risticii, causative agent of equine monocytic ehrlichiosis (potomac horse fever). | adult dogs 1 to 5 were inoculated iv and/or sc with 3, 5, or 6 ml of a suspension containing 1.2 x 10(4) ehrlichia risticii-infected cells (derived from primary canine monocyte cell cultures)/ml. dogs 6 to 8 were inoculated iv and/or sc with 3 or 6 ml of 1.2 x 10(5) organism-free cultured canine monocytes/ml. ehrlichia risticii was isolated in cultures from inoculated dogs 3, 4, and 5 on postinoculation days (pid) 10 to 16, but not from dogs 6 to 8. dogs inoculated with e risticii seroconverted ... | 1988 | 3223656 |
| an epidemiological investigation of farms with potomac horse fever (equine monocytic ehrlichiosis). | 1988 | 3232630 | |
| diphacinone toxicity, von willebrand's disease, and ehrlichia canis in a dog. | 1988 | 3258688 | |
| control of induced infestations of adult amblyomma hebraeum with sustained release ivermectin. | the efficacy of ivermectin, administered in a sustained release formulation by intraruminal pumps at approximate daily dose rates of 20, 40 and 60 micrograms/kg, was evaluated in 16 cattle against induced infestations of 3 strains of adult amblyomma hebraeum. engorged female ticks were mass-measured and incubated, and reproductive data recorded. there was an increase in mortality of male and female ticks compared to that of controls with increasing daily dose of ivermectin, and a decrease in the ... | 1987 | 3295646 |
| serodiagnosis of babesia motasi (wales), theileria recondita (wales) and cytoecetes phagocytophila infection in sheep. | the indirect fluorescent antibody test (ifat) was used to diagnose some tick-borne infections of sheep, babesia motasi (wales), theileria recondita (wales) and cytoecetes phagocytophila. antigen was prepared from blood derived from splenectomised sheep except for c phagocytophila which was derived from a normal animal. a field survey was made to assess the prevalence of b motasi and t recondita in north wales and a comparison made between the titres using the b motasi (wales) antigen with those ... | 1987 | 3306850 |
| heartwater. the development and life cycle of cowdria ruminantium in the vertebrate host, ticks and cultured endothelial cells. | various aspects of the development and life cycle of cowdria ruminantium are discussed. c. ruminantium is transmitted transstadially by certain amblyomma species. apparently organisms initially develop in the gut epithelial cells of ticks and subsequent stages of c. ruminantium invade and develop in the salivary gland acini cells of the vector. stages at which transmission to the final host are attained appear to be coordinated with the feeding cycle of the ticks and the vertebrate host is infec ... | 1987 | 3329309 |
| the present state of cowdria ruminantium cultivation in cell lines. | attempts were made to grow 4 isolates of cowdria ruminantium in cell lines. three of these isolates, viz. ball 3, welgevonden and kwanyanga, could be cultivated in a calf endothelial cell line, but experiments with the kümm isolate have so far failed. the successful in vitro cultivation of 2 isolates (welgevonden and kwanyanga), which are also pathogenic for mice, has great potential for future studies and these aspects are discussed in this review. | 1987 | 3329310 |
| metabolism and genetics of chlamydias and rickettsias. | chlamydial and rickettsial diseases pose a hazard to man and to domesticated and wild animals. the virulence mechanisms which aid the establishment of these obligate intracellular parasites in the eukaryotic host are still not within our grasp. recent knowledge of the biochemical stratagem, the metabolic capabilities and the genetic diversity of these microbes illustrate fundamental differences in ecology and evolutionary divergence. the preferred site of intracellular residence determines the s ... | 1987 | 3329311 |
| purification of cowdria ruminantium by density gradient centrifugation. | the isolation of cowdria ruminantium by differential and isopycnic density gradient centrifugation is reviewed with special reference to the suitability of percoll as density gradient medium. infected sheep brain, amblyomma hebraeum nymphae and various mouse organs were used as starting material. by these methods, partially purified viable populations of the organism with distinctly different densities were obtained. the conclusions are based upon results of analyses of density fractions by inoc ... | 1987 | 3329312 |
| purification of cowdria ruminantium by lectin cellular affinity chromatography. | this review covers the isolation of cowdria ruminantium by lectin cellular affinity chromatography from different amblyomma hebraeum sources. cellular affinity chromatography has been reviewed with special attention being given to the application of this technique in the isolation of rickettsiae. | 1987 | 3329313 |
| purification of cowdria ruminantium by immunoadsorbent affinity chromatography. | immunoselective methods with special reference to immunoadsorbent affinity chromatography as a means for the isolation of cowdria ruminantium are reviewed. attention is given to the source of the organism, immunization, purification of antibodies, coupling of antibodies to insoluble matrixes and desorption procedures. | 1987 | 3329314 |
| heartwater. an overview of the clinical signs, susceptibility and differential diagnoses of the disease in domestic ruminants. | heartwater is a frequently fatal tick-borne disease of ruminants caused by cowdria ruminantium. in domestic ruminants the incubation period varies considerably and depends on the route of infection, virulence of the isolate and amount of infective material administered. adult cattle of all breeds appear to be equally susceptible to heartwater. it is generally accepted that calves up to the age of 3 weeks have a high degree of natural resistance which is not related to the immune status of the da ... | 1987 | 3329315 |
| cowdria ruminantium infection in the mouse: a review. | the current knowledge of the pathogenicity, clinical signs and mortality of artificial infections by syringe inoculation of cowdria ruminantium in laboratory and wild strains of mice is reviewed. it is concluded that a wide spectrum of pathogenicity for mice exists in stocks of the organism. | 1987 | 3329316 |
| heartwater in hosts other than domestic ruminants. | the importance of further research on the susceptibility of wild hosts to cowdria ruminantium infection is discussed. the literature is surveyed and an attempt is made to divide the various species described into susceptible and refractory hosts. the reasons for the numerous apparently conflicting reports are considered and it is suggested that those making further inquiries in this field of work take these factors into account. | 1987 | 3329317 |
| heartwater. the artificial transmission of cowdria ruminantium in domestic ruminants and mice. | the artificial transmission of cowdria ruminantium with infected blood, organ homogenates, peritoneal macrophages, tick stabilate and tissue culture cells is discussed. organ homogenates prepared from the myocardium, spleen, kidneys and liver of diseased animals are commonly used to infect mice. the efficacy of organ homogenates as a source of c. ruminantium depends on factors such as the route of inoculation and the heartwater isolate used. heartwater is artificially transmitted with infected t ... | 1987 | 3329318 |
| the pathology of heartwater. iii. a review. | the pathological changes in cattle, sheep, goats, mice and various game species infected with cowdria ruminantium are summarized. macroscopical lesions in most animals include effusion of body cavities, oedema of the lungs and lymph nodes and splenomegaly. apart from the presence of heartwater organisms in most organs the histopathological lesions are not striking. the ultrastructural lesions in the lungs of sheep and goats infected with the ba11 3 strain of heartwater, and mice infected with th ... | 1987 | 3329319 |
| the pathogenesis of heartwater. | hypotheses on the pathogenesis of heartwater, which have been published so far, are briefly reviewed. attempts were made at counteracting the effects of vaso-active substances released by mast cells by treating mice infected with cowdria ruminantium with antagonists to histamin and serotonin on one hand, and with mast cell stabilizers on the other, but were not successful. preliminary findings suggest that a hypersensitive type of reaction, triggered by the release of pharmacologically active su ... | 1987 | 3329321 |
| the application of the indirect fluorescent antibody test in research on heartwater. | the preparation of the antigen, details of the reagents, the titration of the antispecies conjugates and the execution of the indirect fluorescent antibody test are described. the sensitivity and specificity of the test and its applicability to the detection of antibodies to cowdria ruminantium are recorded. the test is both highly specific and sensitive and can be applied to a wide range of studies on heartwater, including epidemiology, determination of the c. ruminantium infection rate of ambl ... | 1987 | 3329322 |