| rickettsial permeability. an adp-atp transport system. | the obligate intracellular parasitic bacterium, rickettsia prowazeki, has a carrier-mediated transport system for adp and atp. the transport of nucleotides was measured by membrane filtration assays; the assay was shown not to harm the relatively labile rickettsiae. the nucleotide transport system was shown to reside in the rickettsiae, not in the contaminating yolk sac mitochondria of the preparation. the influx of nucleotide had an activation energy of 12 to 13 kcal above 22 deg-rees (an appar ... | 1976 | 1389 |
| the micro-organisms of tsetse flies. | micro-organisms from tsetse fly mycetomes were maintained in culture, where they were more pleomorphic than in the mycetomes, but were in some cases very similar to those observed in ovaries by other authors. agglutination tests on the cultured forms indicated in affinity to rickettsia. they were sensitive to antibiotics introduced by feeding flies on hosts treated with ampicillin; this reduced the longevity and fecundity of the tsetse flies and appeared to disturb normal digestion of bloodmeals ... | 1975 | 1986 |
| enhancement of the antigenic activity and virulence of the vaccine strain e of rickettsia prow azeki by passages in cell culture. | changes in the biological properties of the vaccine strain e of rickettsia prowazeki occurred upon cultivation of a1 (human amnion) cells infected with this strain. in the course of passages of these cells the antigenic activity and virulence of the rickettsia increased. the changes were observed in 10 out of 22 cell cultures examined: in 6 cultures there was an increase in the antigenic activity and in 4 both in the antigenic activity and in virulence. the time of the occurrence of these change ... | 1975 | 1993 |
| periarteritis nodosa with rickettsia-positive serology. | | 1976 | 4769 |
| different allotypic susceptibility of mice to rickett-sia tsutsugamushi. | some lines of mice and random-bred mice show different susceptibility to infection with rickettsia tsutsugamushi, displayed mainly in the development of overt infection. the latter is most markedly manifested in random-bred and swiss mice, causing high death rates and massive accumulation of rickettsiae in the peritoneum. black mice respond to inoculation with asymptomatic infection with no microscopically detectable rickettsiae. the infection is accompanied in either case by immunological respo ... | 1976 | 5869 |
| cytological investigation of rickettsia tsutsugamushi infection of mice with different allotypic susceptibility to the agent. | cytological and cytochemical studies on swiss and random-bred white mice susceptible to rickettsia tsutsugamushi infection as well as resistant c57 black 6 and cba mice revealed a clear-cut relationship between the severity of infection and the pattern of macrophage reaction. in highly susceptible mice the fatal infection was accompanied by death of macrophages and necrotisation of the peritoneal exudate cells. the resistant mice showed no clinical signs but developed an intensive macrophage rea ... | 1976 | 5870 |
| isolation of a lipopoly saccharide antigen from rickettsia species. | | 1976 | 9815 |
| virus- and rickettsia-like structures in gut cells of dermacentor marginatus nymphs. | | 1976 | 11674 |
| the occurrence of an intraerythrocytic microorganism neitziella rezendei gen. nov. sp. nov. (microtatobiotes, rickettsiales) of poultry in brazil. | an extremely polymorphous intraerythrocytic microorganism occurring in naturally infected turkeys, ducks and fowls has been discovered in the states of minas gerais, rio de janeiro and espirito santo. 2. studies on the morphology and biology have shown that it is a hitherto undescribed heteroxenous parasite for which the name neitziella rezendei gen. nov., sp. nov. is proposed. 3. its morphological features permit its inclusion in the class microtatobiotes and order rickettsiales. 4. microscopic ... | 1976 | 13631 |
| antibacterial product of peritoneal exudate cell cultures from guinea pigs infected with mycobacteria, listeriae, and rickettsiae. | in an in vitro model of cellular immunity, the antibacterial product of immunologically mediated mononuclear cell activation was studied from guinea pigs infected with listeriae and rickettsiae and compared with the product previously described from animals infected with mycobacteria. we found that this product, active against gram-positive bacilli, appeared to be identical in the three different infections with regard to its heat stability, its chromatographic adsorption and elution pattern, i ... | 1977 | 15946 |
| enzymatic activity of blood lymphocytes experimental tsutsugamushi fever in mice. | the influence of tsutsugamushi fever infection on the metabolism of blood lymphocytes of mice differing in susceptibility to rickettsia tsutsugamushi and of rifampicine and tetracycline treatment was studied. in susceptible mice, the activity of oxidation-reduction processes in lymphocytes increased at 7--10 days of the disease and became normal upon recovery of the animals. in mice with low susceptibility this increase of the activity began and terminated much earlier, at 3--5 days. treatment o ... | 1977 | 17284 |
| scanning and transmission electron microscopy of rickettsia rickettsii propagated in cell culture. | scanning electron microscopy utilizing critical-point drying and transmission electron microscopy employing air-dried agar pseudoreplicas and critical-point dried carbon replicas were used to study the surface of rickettsia rickettsii propagated in cell culture. | 1977 | 18928 |
| tick-borne diseases in the united states: rocky mountain spotted fever and colorado tick fever. a review. | the historical, clinical, ecological, and epidemiological features of rocky mountain spotted fever and colorado tick fever, the two important tick-borne diseases in the united states, are reviewed. rocky mountain spotted fever, once considered a disease of the past, has again become a measurable public health problem. its nationwide incidence has steadily increased since 1960 and has reached record proportions in 1976. the various factors responsible for this trend as well as for the mortality r ... | 1977 | 19954 |
| transovarial transmission of rickettsia-like microorganisms in mosquitoes. | the wolbachiae found in culex pipiens and the tafahi strain of the a. scutellaris group are small rickettsia-like symbionts of the gonads. they are extrachromosomal self-replicating units that are vertically transmitted through the ovaries. their presence in the only two groups of mosquitoes known to exhibit incompatibility, the fact that they are found in only the tafahi strain, and the loss of incompatibility after removal of wolbachia in c. pipiens are compelling evidence for the role that wo ... | 1975 | 20018 |
| phagocyte lysosomes: interactions with infectious agents, phagosomes, and experimental perturbations in function. | | 1977 | 20833 |
| massive occurrence of rickettsiae of the spotted fever group in fowl tampan, argas persicus, in the armenian s.s.r. | fowl tampans (argas persicus) collected in oktemberyan in the armenian s.s.r. in 1974 were found to be massively infected with rickettsiae of the spotted fever (sf) group. one isolated rickettsial strain, designated armenia 9, is antigenically related to, and probably identical with, strain armenia 11 and strain b of rickettsia slovaca, isolated from dermacentor marginatus ticks. strain armenia 9 grows readily in chick embryo yolk sacs and in chick embryo cell (cec) and l-cell cultures. it cause ... | 1977 | 22239 |
| some biological properties of an endotoxic lipopolysaccharide from the typhus group rickettsiae. | a lipophilic thermostable lipopolysaccharide (lps) complex was isolated by phenol extraction from purified suspensions of the typhus group rickettsiae. the lps complex is antigenic and possesses some endotoxic properties such as toxicity for actinomycin d-treated mice, pyrogenicity for rabbits and guinea pigs, ability to elicit hypothermia in white rats and local schwartzman reaction and active cutaneous anaphylaxis in rabbits. | 1977 | 22240 |
| disease relationships of arthropods in africa with particular reference to mites and ticks. | | 1976 | 24331 |
| progresses in ecology and epidemiology of rickettsioses. | | 1978 | 24997 |
| korean hemorrhagic fever. | | 1978 | 28371 |
| seroepidemiological investigations in domestic ruminants from egypt, somalia and jordan for the demonstration of complement fixing antibodies against rickettsia and chlamydia (author's transl). | 1450 random serum samples of domestic ruminants from egypt, somalia and jordan were investigated for complement fixing antibodies against rickettsia and chlamydia. between 1.5 and 3.4% of the samples from the animals investigated had antibodies against the rmsf-group of rickettsia, with exception of the sera from somalian cattle and sheep from jordan. antibodies against rickettsia of the typhus-group were found in 4 cattle and 1 goat from jordan and 2 sheep from egypt; by agglutination test with ... | 1978 | 28651 |
| experimental infection of hare (lepus europaeus) with coxiella burnetii and rickettsia slovaca. | hares (lepus europaeus l.) infected subcutaneously (s.c.) or per os with coxiella burnetii and s.c. with rickettsia slovaca overcame an inapparent infection accompanied by irregular rickettsaemia and distribution of rickettsiae to different organs and variable antibody response. neither riskettsia could be detected in faeces of infected animals, but c. burnetii was found in the urine of one hare, which died on day 13 post infection (p.i.). antibodies against c. burnetii persisted for one year of ... | 1978 | 30267 |
| [imported diseases from the viewpoint of the microbiologist]. | | 1978 | 31553 |
| differences in the susceptibility of mouse lines to the rickettsial pox agent. | a definite correlation between the susceptibility of spleen macrophage cultures derived from a highly susceptible mouse line (c57bl/6) and a line with low susceptibility (dba/2) and the susceptibility of these mouse lines to infection with rickettsia acari was established. intensive replication of the rickettsiae in cultures from highly susceptible animals caused marked disorders in cell metabolism and eventually death of the culture. cell cultures derived from resistant mice gradually eliminate ... | 1978 | 35948 |
| the influence of temperature and ph on the growth of rickettsia conorii in irradiated mammalian cells. | the temperature range for optimum growth of rickettsia conorii in suspension culture of gamma-irradiated l cells was 32-38 degrees c, resulting in rickettsial doubling times between 4.1 and 6.0 hr. an asynchronous release of r. conorii from host cells was suggested by the constant increase in percent cells infected over a 36 hr period. rickettsial growth was optimal at neutral to slightly alkaline extracellular ph levels. a moderately acidic ph, however, resulted in an increase in doubling time ... | 1979 | 35961 |
| [new aspects of the part of the vector played by ixodes ricinus l. in switzerland. preliminary note (author's transl)]. | the authors, after having recalled their recent work on ixodes ricinus ecology, give the new results about the part played by this species in the transmission of different infectious agents in switzerland. i. ricinus was already known to be the most important vector of the tick borne encephalitis virus, and of protozoans of the babesia genus. in this article, we describe the existence in the hemolymphe of different i. ricinus populations, of a rickettsia species related to the rmst group (rocky- ... | 1979 | 41427 |
| quantitative study on the reproduction of virulent and vaccine rickettsia prow azeki strains in cells of different origin. | vaccine and virulent strains of rickettsia prowazeki differ by the degree of reproduction in mccoy, b, and chick embryo cells but replicate to similar levels in fl cells. as distinct from the virulent breinl strain, the vaccine e strain rickettsiae permanently lost their capacity for long-term reproduction in mccoy cell cultures but retained their capacity to adsorb on to and penetrate into these cells. consequently, the reproduction of rickettsiae is limited at later stages of intracellular inf ... | 1979 | 42302 |
| ixodes ricinus: vector of a hitherto undescribed spotted fever group agent in switzerland. | a tick/rickettsial survey in various parts of switzerland revealed the presence of a new, hitherto undescribed spotted fever group rickettsia ("swiss agent") in up to 11.7% of i. ricinus collected off vegetation. infection in ticks was found to be generalized with rickettsiae developing intracellularly and occasionally also intranuclearly. as a result of massive growth in ovarial tissues, including the germinative cells, the rate of transovarial and filial infection was 100%. the "swiss agent" a ... | 1979 | 44100 |
| serologic classification of scrub typhus isolates from pakistan. | detailed serologic characterization of 79 isolates of rickettsia tsutsugamushi from pakistan was performed by using complement fixation and direct immunofluorescence techniques for comparison with three prototype strains. seventy-one were of the karp serotype and one was of a gilliam serotype. seven isolates were multiply-reactive: one with karp and gilliam, 3 with karp and kato, and 3 with karp, gilliam and kato, no strain failed to react with at least 1 of the 3 prototype antisera. no correlat ... | 1975 | 46135 |
| electron microscopy studies of the limiting layers of the rickettsia coxiella burneti. | surface layers of coxiella burneti studied at a high resoulution reveal a plasma membrane and an outer surface membrane 6 to 7 nm thick, and a thin, moderately electron-dense intermediate layer associated with the inner surface of the outer membrane of many cells. this layer appears to be unaffected by lysozyme treatment. ruthenium red staining was used to delineate a layer of filamentous material external to the outer membrane; this fuzzy layer has a mean thickness of 20 nm and is not often see ... | 1975 | 47324 |
| [current significance of rickettsial diseases]. | | 1975 | 47603 |
| [immunofluorescence reaction of microagglutination of rickettsia]. | | 1975 | 50495 |
| the soluble antigens of rickettsia prowazeki, r. typhi and r. canada. investigation of their interrelationship by various serological methods. | the purpose of this research is the isolation of an eventual species-specific fraction from the "soluble antigen" of rickettsiae. the "soluble antigen" of r. prowazeki (breinl strain), r. typhi (wilmington strain) and r. canada were purified at 25% saturation with ammonium sulphate (psa). corresponding antisera were produced in rabbits. the serological methods used were the complement fixation, the micro-agglutination, the precipitation method in capillary tubes and the immuno-diffusion method c ... | 1975 | 52235 |
| [immunologic comparison between some wolbachiae and research of antigentic community with other members of the order of rickettsiales]. | the antigenic relationship between some rickettsiae of arthropods, which do not transmit germs pathogenic to vertebrates was investigated by agglutination and immunofluorescence techniques. the comparison of r. melolonthae, r. tipulae, r. cetonidarum, r. grylli and of the rickettsiae of the scorpion buthus occitanus shows that the wolbachiae are divided into three serological groups. the insect crystallogen rickettsiae belong to the first group, r. grylli and the scorpion rickettsia are antigeni ... | 1975 | 53109 |
| the practice laboratory: the interpretation of blood smears. | | 1975 | 53937 |
| editorial: chronic q fever or q fever endocarditis? | | 1976 | 58210 |
| [current data. 1. infectious diseases: number of reported cases and registered deaths in 1974 and in 1975]. | | 1976 | 59470 |
| [immunofluorescent test of rickettsia microagglutination. 3. isolation of antibodies to rickettsia quintana]. | | 1976 | 62095 |
| world health statistics report. | | 1976 | 62460 |
| rickettsia-like bodies and splenitis in kawasaki disease. | | 1976 | 63083 |
| electron microscopy of surface structures of rickettsia prowazeki stained with ruthenium red. | in studying surface structures of rickettsia prowazeki (e and breinl strains) by ruthenium red staining, a microcapsular layer 125-165 a thick, composed of subunits 85--100 a in diameter with a periodicity of 100--120 a as well as the inner layer of the cell wall 40--60 a thick were clearly revealed. in tangential sections of cells, subunits of the microcapsular layer were found in parallel striation arrays. these structures presumably contain acid mucopolysaccharides detectable by ruthenium red ... | 1976 | 63238 |
| a passive hemagglutination test for diagnosis of trench fever due to rochalimaea quintana. | a passive hemagglutination test devised for diagnosis of trench fever was easily performed and highly sensitive and specific. tanned sheep erythrocytes were sensitized with soluble antigen from rochalimaea quintana. the test detected antibody in six of seven cases of primary infection and in four cases of late, relapsed trench fever. titers of antibody ranged from 1:20 to 1:640. although both igm and igg antibody to r. quintana were detected by passive hemagglutination, igg appeared to be the ma ... | 1976 | 63526 |
| characterization of the madrid e strain of rickettsia prowazekii purified by renografin density gradient centrifugation. | the avirulent madrid e strain of rickettsia prowazekii cultivated in chicken yolk sacs could be purified successfully with a renografin density gradient method developed previously for rickettsia typhi. recovery during purification, viability, and lack of contamination with host cell components were similar for the two species, although yields of r. prowazekii per yolk sac were lower. purified typhus rickettsiae provided satisfactory antigens in the complement fixation, ouchterlony double-diffus ... | 1977 | 64456 |
| [effect of several long-acting broad spectrum antibiotics on prowazek rickettsia]. | | 1976 | 64918 |
| [experimental infection of domestic animals with r. prowazeki and r. canada]. | the authors infected lambs with r. prowazeki and r. canada to ascertain their possible role in the natural infection of the animals. the lambs were infected subcutaneously with increasing doses; rickettsiemia was recorded with the aid of tests on guinea pigs and ixodidae and argasidae ticks fed on the lambs. dynamics of antibody formation was ascertained in the infected animals in the agglutination reaction and in the complement fixation test. the antigenic affinity of r. canada and rickettsia o ... | 1976 | 65076 |
| plaque assay and cloning of scrub typhus rickettsiae in irradiated l-929 cells. | it was demonstrated that gamma-irradiated l-929 cells support plaque formation by three strains of rickettsia tsutsugamushi and representative species of the spotted fever and typhus group rickettsiae. sensitivity of the plaque assay for detection of viable scrub typhus rickettsiae was similar to that achieved with intraperitoneal inoculation of random-bred mice. the concentration of irradiated cells and the temperature and length of incubation were all found to affect plaque size. a technique c ... | 1977 | 69632 |
| staining of rickettsial antigens for microagglutination reaction. | staining of antigens of r. prowazeki, r. canada and r. conori with hematoxylin-harris for use in mar was developed. optimal results were obtained when rickettsial antigens were stained at 4 degrees c for 18 hours. comparison of mar with cfr has shown that mar using stained rickettsial antigens is specific and as sensitive as cfr. | 1977 | 69657 |
| infections diseases: monthly or four-weekly number of reported cases, 1976 and 1977. | | 1977 | 73263 |
| [detection of antigen of rickettsia of the tick group in bird droppings by antibody neutralization test]. | the author presents methodical materials pointing to a possibility of using a micromethod of the antibody neutralization test for detection in bird pellets of the antigen of rickettsia referred to the rocky mountains spotted fever tick group. specificity of the test, rickettsia antigen and sera was studied. the method is recommended for detection at the territory under study of circulation of the causative agent of tick-borne rickettsiosis by revealing the specific antigen in bird pellets. | 1978 | 79279 |
| external layers of rickettsia prowazekii and rickettsia rickettsii: occurrence of a slime layer. | using a simple specific-antibody stabilization procedure on organisms gently liberated from their host cells, we have demonstrated by electron microscopy that rickettsia prowazekii and rickettsia rickettsii possess a coat of variable thickness, external to the outer leaflet of the cell wall and the structure designated by others as a "microcapsule," which corresponds most closely to the slime layer of certain other bacteria. reactions in the methenamine silver and ruthenium red staining procedur ... | 1978 | 83297 |
| electrophoretic changes in serum transferrin and gammaglobulins following rickettsia mooseri infection in cyclophosphamide treated mice. | | 1978 | 83756 |
| [chronic bullous polymorphic erythema]. | | 1979 | 87350 |
| simple, differential staining technique for enumerating rickettsiae in yolk sac, tissue culture extracts, or purified suspensions. | a differential staining method employing acridine orange-stained rickettsiae and safranin-stained standardized suspensions of shigella dysenteriae is described for enumerating rickettsiae harvested during various stages of the growth cycle. | 1979 | 88460 |
| chronic cryptic q-fever infection of the heart. | evidence of chronic coxiella burneti infection of the heart, a disease previously considered peculiar to patients with valvular heart-disease, was found in a patient during routine serological tests before resection of a ventricular aneurysm and also by isolation of the rickettsia from the resected tissue. the patient had no symptoms or signs of q-fever endocarditis and none of the laboratory evidence usually associated with it. | 1979 | 88607 |
| [physiopathology of rickettsial and/or pararickettsial diseases of the eye]. | | 1979 | 88795 |
| [an experimental infection of hyalomma asiaticum and ornithodoros papillipes ticks with a single and combined infection with coxiella burnetii and dermacentroxenus sibericus]. | experimental infection of h. asiaticum and o. papillipes with coxiella burnetii and r. (d.) sibericus in different succession and individual study of these arthropods by means of the fluorescent antibodies method, ordinary microscopy and titration on laboratory animals have revealed an ambiguous outcome of the development of combined rickettsial infection in these ticks. the first agent obtained by the vector either prevents utterly the reproduction of the heterologous agent or inhibits its acti ... | 1979 | 95820 |
| energy metabolism of rickettsia typhi: pools of adenine nucleotides and energy charge in the presence and absence of glutamate. | the obligate intracellular bacterium rickettsia typhi was examined for its ability to generate and maintain an adenylate energy charge in an extracellular environment. freshly purified organisms were incubated, at 34 degrees c and ph 7.4, with or without glutamate and various other metabolites, and the levels of atp, adp, and amp were determined. of the metabolites tested, glutamate and glutamine were the most effective for the generation of atp. in the presence of glutamate, there was a rapid i ... | 1978 | 96104 |
| laboratory diagnosis of rocky mountain spotted fever by immunofluorescent demonstration of rickettsia in cutaneous lesions. | direct immunofluorescent staining for rickettsia rickettsii was performed on cryostat sections of skin biopsies from 27 patients suspected of having rocky mountain spotted fever. in nine of the 17 patients whose final diagnosis was rocky mountain spotted fever, coccobacillary forms of r. rickettsii were identified in endothelium and vascular walls within the dermis. facotrs recognized as contributing to false-negative results were prior treatment with tetracycline or chloramphenicol for 24--48 h ... | 1978 | 96691 |
| [serological survey of animal rickettsioses in cameroon. i. evaluation of the threshold of positivity and specificity of the micro-agglutination reaction as related to the size of the animal]. | | 1977 | 96947 |
| [serological survey of animal rickettsioses in cameroon. ii. results of the survey]. | | 1977 | 96948 |
| effect of immunosuppression on rickettsia rickettsii infection in guinea pigs. | the role of the immune response in the pathogenesis of rickettsia rickettsii infection in guinea pigs was investigated by immunosuppression, using antilymphocyte serum. twenty guinea pigs were inoculated with r. rickettsii, sheila smith strain, on day 0. fifteen animals received antilymphocyte serum on days --1, 0, 2, 4, and 6. five animals received normal rabbit serum on the same schedule. at necropsy, specimens were collected for histological examination, rickettsial immunofluorescence, ricket ... | 1978 | 97223 |
| detection of the rocky mountain spotted fever agent, rickettsia rickettsii, in dead ticks, dermacentor andersoni. | rickettsia rickettsii remained viable and retained chromophilic properties for not more than 24 h after dermacentor andersoni were killed by freezing. antigenic reactivity was detected for at least 71 days by direct immunofluorescence. however, rickettsiae in ticks suffocated with mineral oil remained pathogenic for at least 14 days. accordingly, ticks removed from a host by mineral oil or dying from desiccation in transit are still suitable for rickettsial examination. | 1978 | 97233 |
| prophylactic treatment of rocky mountain spotted fever. | prophylactic treatment of rocky mountain spotted fever with a single dose of oxytetracycline was investigated in guinea pigs. disease was prevented when treatment was administered shortly before expected onset. relapses occurred when treatment preceded expected onset by 48 h or more. | 1978 | 97307 |
| rickettsiae: a new vaccine for rocky mountain spotted fever. | | 1978 | 97783 |
| [the effect of various antibiotics on the formation of typhus antibodies following immunization with typhus vaccine]. | it was shown that administration in the course of one week, before or after a single use of killed or chemical typhoid vaccine of dibiomycin, biomycin, or biomycin in combination with erythromycin in comparatively high doses produced no negative effect of the production of typhus antibodies and the intensity of antitoxic immunity in albino mice. the same antibiotics failed to influence the antibody formation in guinea pigs if they produced no toxic effect on the animals; but in case of developme ... | 1978 | 97881 |
| alterations of body fluid compartments and distribution of tissue water and electrolytes in rhesus monkeys with rocky mountain spotted fever. | chair-restrained rhesus monkeys (macaca mulatta) were inoculated subcutaneously with 10(2)--10(3) plaque-forming units of virulent rickettsia rickettsii. the latent period for fever and rickettsemia was three to four days; death occurred six to eight days after infection. total circulatory electrolyte levels and fluid volumes, including plasma, red blood cell, true circulatory blood, and extracellular fluid, increased. the expansion of the extracellular and plasma volumes resembled findings repo ... | 1978 | 98595 |
| stylostome formation by leptotrombidium mites (acari: trombiculidae). | the modes of stylostome formation by larvae (chiggers) of leptotrombidium intermedium, l. fletcheri, l. arenicola, and l. deliense in parasitized mouse skin were studied histologically in relation to their capacity to transmit rickettsia tsutsugamushi. three types of stylostome formation were recognized among the different species: the epidermal stylostome formed by the larva of l. intermedium; the mesenchymal stylostome formed by the larva of l. fletcheri; and, the mixed stylostome formed by th ... | 1978 | 98623 |
| antigenic relationships between the typhus and spotted fever groups of rickettsiae. | paired sera from cases of epidemic typhus in ethiopia and from probable cases of rocky mountain spotted fever (rmsf) in the united states were examined by microagglutination (ma) and microimmunofluorescence (micro-if) tests for antibodies against rickettsia prowazekii, rickettsia typhi, rickettsia canada, rickettsia rickettsii, rickettsia conorii and ricksettsia akari. igg and igm antibodies against the various rickettsiae were titrated with specific fluorescein-conjugated anti-igg and anti-igm ... | 1978 | 99029 |
| mechanisms of immunity in typhus infection: some characteristics of rickettsia mooseri infection of guinea pigs. | rickettsia mooseri infection has been studied in syngeneic guinea pigs inoculated intradermally with the objective of developing a model for the study of immune mechanisms. characterization of infection included the following: a study of replication, dissemination, and clearance of rickettsiae; measurement of the antibody response with different rickettsial antigens and tests; and attempts to measure the cell-mediated immune response using the correlate of delayed-type hypersensitivity skin reac ... | 1978 | 99367 |
| some ultrastructural effects of persistent infections by the rickettsia coxiella burnetii in mouse l cells and green monkey kidney (vero) cells. | mouse fibroblasts (l-929) and vero (green monkey kidney) cells were infected with the rickettsia coxiella burnetti, and persistent infections developed and were studied over a 6- to 10-month period. ultrastructural comparisons were made between the two infected cell types, and both were tested cytochemically for the presence of acid phosphatase, a marker enzyme of lysozymes. rickettsiae were always observed within vacuoles, and some infected l cells showed flattened endoplasmic reticulum as comp ... | 1978 | 99368 |
| plaque formation by strains of spotted fever rickettsiae in monolayer cultures of various cell types. | some strains of spotted fever rickettsiae could be distinguished by their ability or inability to form plaques in monolayer cultures of various mammalian and avian cell types. | 1978 | 99454 |
| [indirect hemagglutination test at the ultrastructural level]. | a study on ultra-thin sections was made of the preparations of agglutinate produced during the reaction of the immunoglobulin erythrocytic diagnostic agent with dry corpuscular rickettsia prowazeki antigen, fluoresceine isothiocyanate labeled, and also srbc used for the preparation of the diagnostic agent after formalinization, tannin treatment, sensitization with hyperimmune horse serum immunoglobulins and lyophilization, respectively. formalin and tannin treatment of erythrocytes failed to be ... | 1978 | 99928 |
| an apparent outbreak of rickettsial illness in costa rica, 1974. | a focal outbreak of highly fatal disease occurred in eastern costa rica in 1974. no rickettsial spotted fevers have previously been reported in costa rica. nevertheless, the available evidence points to an unidentified rickettsial pathogen, probably of the spotted fever group, as the agent responsible for this outbreak. | 1978 | 100162 |
| identification of rickettsia rickettsii in formalin-fixed, paraffin-embedded tissues by immunofluorescence. | with slight modification of a trypsin digestion technique, rickettsia rickettsii were demonstrated specifically by immunofluorescence staining in formalin-fixed, paraffin-embedded tissue sections from a human, rhesus monkey, and guinea pig with rocky mountain spotted fever and in infected membranes from a chicken embryo. tissues were cut at 4 micron and, using geltain as a tissue adhesive, were hydrated in a routine manner. sections were then digested in refrigerated 0.1% trypsin for 16 h, washe ... | 1978 | 100509 |
| early detection of rickettsia tsutsugamushi in peripheral monocyte cultures derived from experimentally infected monkeys and dogs. | rickettsia tsutsugamushi organisms were identified in giemsa and fluorescent antibody stained monocyte cell cultures derived from experimentally infected monkeys and dogs. the identification of organisms in monocyte cell cultures compared favorably with the standard technique of mouse inoculation. | 1978 | 100887 |
| comparative ultrastructural study on the cell envelopes of rickettsia prowazekii, rickettsia rickettsii, and rickettsia tsutsugamushi. | rickettsia tsutsugamushi differs from other rickettsiae in its cell envelope organization. the differences were made evident through a comparative study of the outer envelope of r. tsutsugamushi, r. prowazekii, and r. rickettsii by electron microscopy. | 1978 | 101465 |
| surface proteins of typhus and spotted fever group rickettsiae. | six proteins, previously established as major constituents of intact organisms, were identified in cell envelopes obtained from intrinsically radiolabeled rickettsia prowazekii. extrinsic radioiodination of intact organisms conducted at 0.5 micronm iodide indicated that protein 4 was the most peripheral, although protein 1 also had reactive groups exposed on the surface of the organisms. a 10-fold increase in iodide concentration resulted in labeling of protein 2, and at 50 micronm iodide, all s ... | 1978 | 101466 |
| phospholipid composition of rickettsia prowazeki grown in chicken embryo yolk sacs. | the phospholipid composition and phospholipid fatty acid composition of purified rickettsia prowazeki were determined. the lipid phosphorous content was 6.8 +/- 1.3 microgram/mg of total rickettsial protein. the major phospholipid was phosphatidylethanolamine (60 to 70%); phosphatidylglycerol constituted 20%, and phosphatidylcholine constituted 15%. small amounts of phosphatidylserine and cardiolipin were detected. the principal fatty acids were 18:1, 16:1, and 16:0. the fatty acid composition o ... | 1978 | 101511 |
| absence of hydrogen peroxide production by or catalase action in rickettsia prowazeki. | glutamic acid oxidation by rickettsia prowazeki is not accompanied by hydrogen peroxide generation, nor is added hydrogen peroxide degraded, as measured by a manometric technique. | 1978 | 101521 |
| serologic typing of rickettsiae of the spotted fever group by microimmunofluorescence. | | 1978 | 101593 |
| [immunological study on rickettsia sennetsu by complement-fixation test (author's transl)]. | | 1978 | 101610 |
| [studies on the causative agent of hyuga-feveri; cultivation of rickettsia-like organisms isolated from metacercariae of stellantchasumus falcatus in tissue culture cell and their antigenic relation to rickettsia sennetsu (author's transl)]. | | 1978 | 102710 |
| [effect of antibiotics and combined preparations on the toxic properties of rickettsia prowazekii]. | | 1978 | 102906 |
| [effect of prodigiozan on the course of experimental rickettsial intoxication]. | | 1978 | 102909 |
| [detection of antibodies to rickketsia prowazekii by using the antigen neutralization test]. | the authors studied a possibility of using the antigen neutralization test with dry immunoglobulin typhus erythrocytic diagnostic agent for the purpose of detection of rickettsia prowazeki antibodies. blood sera of 315 healthy persons, 24 patients with sporadic typhus, and 18 laboratory animals immunized with r. sibirica and r. burneti, as well as with proteus ox19 were examined. the results obtained pointed to the high specificity and sensitivity of the given serological test. a possibility of ... | 1978 | 103341 |
| distribution and prevalence of spotted fever group rickettsiae in ticks from south carolina, with an epidemiological survey of persons bitten by infected ticks. | live ticks removed from human hosts were tested for the presence of spotted fever group rickettsiae from 1974 through 1976. spotted fever group rickettsiae were detected in dermacentor variabilis, amblyomma americanum, amblyomma maculatum, and ixodes scapularis. persons from whom positive ticks were removed in 1974 and 1975 were questioned about ensuing illness. eleven of 51 persons from whom rickettsia-positive d. variabilis were removed reported some unexplained combination of symptoms compati ... | 1978 | 103448 |
| identification and antigenic typing of rickettsia tsutsugamushi in naturally infected chiggers (acarina: trombiculidae) by direct immunofluorescence. | rickettsia tsutsugamushi organisms were detected and typed antigenically by direct immunofluorescence in mites from laboratory-maintained infected colonies of leptotrombidium (leptotrombidium) fletcheri and l. (l.) arenicola. rickettsiae were identified most readily in unengorged larvae, but were also discernable in engorged larvae and all post-larval stages of the vectors. | 1978 | 103449 |
| effects of temperature on the stability of rickettsia tsutsugamushi and gamma-irradiated scrub typhus immunogens. | unirradiated rickettsia tsutsugamushi and a component of gamma-irradiated karp immunogen required for homologous immunity were more stable than the immunogen component that elicited heterologous (kato strain) protection. | 1978 | 103827 |
| gamma-irradiated scrub typhus immunogens: development and duration of immunity. | the development and duration of immunity to lethal scrub typhus infection was studied in balb/c mice vaccinated with gamma-irradiated rickettsia tsutsugamushi, strain karp. one intraperitoneal injection containing approximately 10(8) 50% mouse lethal doses (mld(50)) of irradiated organisms elicited an immune response protective against challenge with 10(5) mld(50) of viable karp. the same mass of immunogen given in three injections at 5-day intervals increased homologous (karp strain) protection ... | 1978 | 103828 |
| [antigen for the indirect hemagglutination reaction from rickettsia prowazekii cultured in the body of the carrier]. | | 1978 | 104130 |
| [boutonneuse fever in tourists as a model for clinical diagnosis of rickettsioses (author's transl)]. | case histories of boutonneuse fever are described in order to exemplify major characteristics of most rickettsioses: recent travel history, feverish illness with severe headache, skin eruptions and histological findings. up-to-date informations concerning the epidemiologic situation of typhus, scrub typhus and rocky mountain spotted fever are given. the characteristics of q fever and the possibility of rickettsial laboratory infections are pointed out. | 1979 | 104166 |
| growth of rickettsia typhi in irradiated l cells enhanced by lysosomal stabilization. | the growth of some obligate intracellular parasites is contingent upon avoidance of lysosomal activation during growth in their host cells. this is accomplished by the various parasites by different mechanisms and with different degrees of efficiency. the possibility was tested that the lysosomal stabilizer cortisone acetate might protect and thus enhance the growth of rickettsia typhi in mouse l cells irradiated 6 days earlier. beginning 2 days before infection of the l cells with a multiplicit ... | 1979 | 106007 |
| separation of inner and outer membranes of rickettsia prowazeki and characterization of their polypeptide compositions. | rickettsia prowazeki were disrupted in a french pressure cell and fractionated into soluble (cytoplasm) and envelope fractions. the envelope contained 25% of the cell protein, with the cytoplasm containing 75%. upon density gradient centrifugation, the envelope fraction separated into a heavy band (1.23 g/cm3) and a lighter band (1.19 g/cm3). the heavy band had a high content of 2-keto-3-deoxyoctulosonic acid, a marker for bacterial lipopolysaccharide, but had no succinic dehydrogenase, a marker ... | 1979 | 106046 |
| sensitive microplate enzyme-linked immunosorbent assay for detection of antibodies against the scrub typhus rickettsia, rickettsia tsutsugamushi. | a microtiter enzyme-linked immunosorbent assay (elisa) has been developed for the titration of antibodies against scrub typhus in human and animal sera. scrub typhus rickettsiae were grown in monolayers of irradiated mouse lm3 cells and separated from host cell materials by differential centrifugation, filtration through a glass filter (ap-20, millipore corp.), and isopycnic banding in renografin density gradients. the scrub typhus elisa antigens were obtained from the purified viable rickettsia ... | 1979 | 107185 |
| discrepancies in weil-felix and microimmunofluorescence test results for rocky mountain spotted fever. | only 4.2% of 284 single specimens and 17.6% of 51 pairs of sera reactive in weil-felix agglutination tests for rocky mountain spotted fever were confirmed by a specific rickettsia rickettsii microimmunofluorescence test. | 1979 | 107194 |
| rickettsia tsutsugamushi infections in chiggers and small mammals on a mature oil palm estate. | an epidemiological study in a mature oil palm estate in peninsular malaysia has demonstrated a low prevalence of r. tsutsugamushi infection in small mammals. the direct fluorescent antibody technique for assaying infections in chiggers proved more sensitive than mouse inoculation. most infections in both chiggers and rodents were caused by the karp strain. | 1978 | 107596 |
| [importance of humoral immunity indices in determining the rickettsia prowazekii carrier state]. | experiments showed the possibility of making indirect conclusions concerning rickettsial carrier state by the method of determination of complement-fixing antibodies to r. prowazeki in the blood serum. though not indicative of carrier state in individual animals, these antibodies, their dynamics and titers gave the evidence of group carrier state in cotton rats in respect of the causative agent of typhus. the number of animals carrying r. prowazeki increased with the rise of antibody titers. neg ... | 1979 | 110016 |
| mechanisms of immunity in typhus infection: adoptive transfer of immunity to rickettsia mooseri. | when nonimmune guinea pigs are inoculated intradermally (i.d.) with rickettsia mooseri (r. typhi), the rickettsiae replicate at the site of inoculation, leading to the development of a grossly observable lesion. in contrast, guinea pigs which have recovered from r. mooseri infection are resistant to challenge and prevent both rickettsial growth and the formation of lesions. to study the mechanisms of this immunity, sera or splenic cells collected from nonimmune or immune guinea pigs were inocula ... | 1979 | 110699 |
| rocky mountain spotted fever in connecticut: human cases, spotted-fever group rickettsiae in ticks, and antibodies in mammals. | three parameters were used in 1976 and 1977 to assess the status of rocky mountain spotted fever (rmsf) in connecticut--compilation and review of clinical data on suspected human cases for the 13-year period 1965--1977, examination of tick tissues for spotted fever-group rickettsiae by the hemolymph test and direct immunofluorescence, and analyses of mammalian sera for antibodies against rickettsia rickettsii. there were six presumptive rmsf cases which probably originated in connecticut. four o ... | 1979 | 111543 |
| rickettsial hemolysis: rapid method for enumeration of metabolically active typhus rickettsiae. | a new assay is described for enumerating biologically active typhus rickettsiae (madrid e strain), based on adsorption of rickettsiae to erythrocytes in the presence of naf (which allows adsorption but not lysis) and lysis in the presence of anti-rickettsia prowazeki immune serum (which allows only a single round of lysis). the number of lysed erythrocytes is then used to estimate the number of active rickettsiae. | 1979 | 113426 |