| [experimental infection of soft ticks with dipetalonema witei (author's transl)]. | the intermediate host of dipetalonema witei, the soft tick ornithodoros moubata, can be infected experimentally with microfilariae. microfilariae isolated from the blood of infected donor animals were injected into the dorsal haemocoel of the ticks where they developed to infectious filariae within approx. 50 days. the rate of infection of ticks was 100% when more than 100 microfilariae were injected. an average of 23% was recovered as infectious filariae. up to 450 ticks can be infected with 10 ... | 1979 | 573516 |
| african swine fever: an epizootiological review with special reference to the south african situation. | the most important characteristics and the distribution of the viruses of african swine fever and hog cholera are reviewed. both viruses were probably present simultaneously in south africa in the first two decades of the century. while hog cholera was eradicated by 1918, african swine fever persists to the present day because it has a different epizootiology. the role played by wild pigs and the argasid tick (ornithodoros moubata porcinus) in the epizootiology of african swine fever is discusse ... | 1975 | 768472 |
| ornithodoros moubata: breeding in vitro. | | 1977 | 885208 |
| the maintenance of the argasid tick ornithodoros moubata (murray) on embryonated hen eggs. | a laboratory colony of o. moubata was maintained entirely by feeding on the exposed membranes of embryonated hen eggs at the 17-19th day stage of incubation at 37 degrees c. there was no loss of either vigour or fecundity. the method gave markedly superior results to those obtained by feeding on rabbits, rats, mice and guinea-pigs. more convenient and economical than any alternative, the method has valuable advantages in its applicability to a wide range of pathogens. | 1976 | 968952 |
| [observations on the behaviour of coxiella burneti in the argasid tick ornithodoros moubata (author's transl)]. | based on a long-term study of many years, a report is given on the behaviour of coxiella burneti in the argasid tick, ornithodoros moubata. recent observations were made on ticks infected on mice and subsequently maintained separately. particular emphasis was placed upon the localization of the ricksettsiae in certain organs of the ticks, its excretion -also with regard to routes of transmission - and transovarial passage. c. burneti invade primarily the gut epithelial cells of the tick and thes ... | 1975 | 1172309 |
| an assembly pheromone and its perception in the tick ornithodoros moubata (murray) (acari: argasidae). | | 1975 | 1181431 |
| the effect of erythromycin on the growth of rickettsia prowazekii in the body louse (pediculus humanus corporis l) and the tick (ornithodoros moubata murray). | body lice (pediculus humanus corporis l) and ticks (ornithodoros moubata) that had been infected with rickettsia prowazekii received varying doses of erythromycin. the anti-rickettsial activity of this drug was evaluated with regard to the determination of the numbers of surviving microorganism (lid100) and the in vivo concentration of erythromycin in both arthropod hosts. erythromycin was found to exert a rickettsiostatic effect in lice, whereas in ticks the drug at concentrations of 0.3--0.04 ... | 1976 | 1253630 |
| the identification of a shared immunogen present in the salivary glands and gut of ixodid and argasid ticks. | the identification of a 70-kda immunogen present in salivary gland extracts of several ixodid species, namely hyalomma truncatum (sweating-sickness-inducing (ss+) and non-inducing (ss-) strains), hyalomma marginatum rufipes and rhipicephalus evertsi evertsi, is reported. the immunogen was identified by western blots using a monoclonal antibody of the igm isotype directed against a 70-kda immunogen present in the salivary glands of (ss-) female h. truncatum ticks. cross-reactivity with the gut of ... | 1992 | 1446571 |
| [the use of cryopreserved swine blood for in vitro feeding of the soft tick ornithodoros moubata]. | porcine stored blood has been used in the in vitro feeding of the soft tick ornithodoros moubata through a parafilm membrane. the efficiency of the feeding decreased after storage of 5 weeks by -20 degrees c. through addition of 10(-3) m atp/l the feeding results with frozen blood for duration of storage up to 200 days well agreed with the results of feeding tests with fresh porcine blood: the nymphs (n)1-3 fed the 4-5fold, the n4-6 the 2.7fold and the adults (a) the 1.9fold of their body weight ... | 1992 | 1456462 |
| effects of precocenes on vitellogenesis in the adult female tick, ornithodoros moubata (acari: argasidae). | vitellogenin (vg) concentrations in the hemolymph and ovarian development were studied in ornithodoros moubata after treatment with precocenes 1 (p1) and 2 (p2). precocene was dissolved in acetone or dmso and topically applied to the dorsal surface of ticks: (1) at adult ecdysis; (2) 24 h before engorgement; (3) immediately after engorgement; and (4) 24 h after engorgement. subsequently, p1 and p2 were dissolved in olive oil and injected through the gonopore into the body cavity 24 h after engor ... | 1992 | 1638926 |
| saliva of the soft tick, ornithodoros moubata, contains anti-platelet and apyrase activities. | 1. pilocarpine-induced saliva of the soft tick ornithodoros moubata inhibits platelet aggregation induced by adp or collagen, even when diluted 2000 times into platelet rich plasma. 2. saliva contains apyrase (atp-diphosphohydrolase) activity, which has an optimal ph of 7.0 for adp and of 8.0 for atp hydrolysis, respectively. both ca2+ and mg2+ activate the reactions. 3. the mean specific activities for atp and adp hydrolysis at ph 7.5 were 0.97 and 0.74 mumoles orthophosphate/min/mg protein. 4. ... | 1991 | 1682082 |
| artificial feeding and successful reproduction in ornithodoros moubata moubata (murray, 1877) (acarina: argasidae). | the increasing demand for laboratory-reared argasid and ixodid ticks for research and control purposes makes it necessary to develop effective and standardized tick feeding methods without using live animals as hosts. the in vitro maintenance technique, described in this paper, has been used successfully for rearing ornithodoros moubata moubata by feeding all nymphal and adult instars through parafilm 'm' sealing film on heparinized bovine blood (fresh standard). the technique is based on a spec ... | 1991 | 1786742 |
| stimulation of vitellogenesis by pyrethroids in mated and virgin female adults, male adults, and fourth instar females of ornithodoros moubata (acari: argasidae). | the effects of several pyrethroids on vitellogenesis, i.e., vitellogenin (vg) synthesis and ovarian development in unfed mated female adults of ornithodoros moubata were investigated. survival of ticks treated with pyrethrin, resmethrin, and etophenprox was very low. ticks treated with cypermethrin (cym), fenvalerate (fev), and flucythrinate (flu) survived even when high concentrations were used. vg titer in the hemolymph of unfed mated females was the same level on day 5 and about three times h ... | 1991 | 1875360 |
| cuticle deposition and ecdysteroid titers during embryonic and larval development of the argasid tick ornithodoros moubata (murray, 1877, sensu walton, 1962) (ixodoidea:argasidae). | timing of embryonic and larval molts at the ultrastructural level and presence of ecdysteroids (es) during embryonic and larval development of the argasid tick ornithodoros moubata were studied. embryonic "cuticles" a, b, and c were deposited 24-30 hr, 48-56 hr, and 6 days after oviposition, respectively. deposition of the larval cuticulin layer started on day 8 of embryonic development and procuticle deposition continued after hatching until apolysis of the larval cuticle 40 hr posthatch. plaqu ... | 1991 | 1879655 |
| demonstration of regurgitation of gut content during blood meals of the tick ornithodoros moubata. possible role in the transmission of pathogenic agents. | nymphs of ornithodoros moubata were fed tritiated ecdysteroid. these ingested hormones are conjugated to fatty acyl esters that accumulate in the midgut (connat et al. 1988). a few months later, the same ticks which had molted, were fed on physiological medium without radiolabel. at the issue of the blood meal, the nutritive medium contained an amount of radiolabel corresponding to 0.5% of the total labelling in the animal before the blood meal; this corresponded to 1.3% of the midgut content. t ... | 1991 | 1891454 |
| effects of juvenile hormone and its analogs on vitellogenin synthesis and ovarian development in ornithodoros moubata (acari: argasidae). | effects of juvenile hormones (jh) and jh analogs on the release of vitellogenin (vg) into the hemolymph and ovarian development in unfed adult female ticks, ornithodoros moubata (murray), were investigated. topical application of acetone solvent and injection of acetone or oils showed some increase in vg titer in the hemolymph. topical application of jh (jh i, jh ii, jh iii) and jh analogs (methoprene, s21149, s21150, and s31183) dissolved in acetone to unengorged adult females elevated vg titer ... | 1991 | 1941910 |
| attempts to transmit hepatitis b virus to chimpanzees by arthropods. | bedbugs (cimex lectularius l.) were fed on an infective blood-hepatitis b virus (hbv) mixture. further bedbugs and tampan ticks (ornithodoros moubata [murray]) were fed on hbv-carrier chimpanzees. after a 10-13 day interval for oviposition, tests done on samples of individual arthropods showed that 53-85% of the bugs were hbsag-positive and none hbeag-positive, while 100% of the ticks were hbsag-positive and 88% hbeag-positive. the remaining arthropods were fed on 3 susceptible chimpanzees, whic ... | 1991 | 2017742 |
| serological markers of hepatitis b virus and certain other viruses in the population of eastern caprivi, namibia. | serum samples from 475 male and 420 female subjects from the population of eastern caprivi, the north-easternmost territory in northern namibia, were examined for the presence of hepatitis b surface antigen (hbsag), antibodies to hbsag (anti-hbs) and hepatitis b core antigen (anti-hbc). there appeared to be a rapid acquisition of antibodies to the different markers in childhood, reaching maximum values in the 20-24 year age group. the prevalence rate for all markers was lower in eastern caprivi ... | 1991 | 2068734 |
| [focus of borreliosis in gisenyi (rwanda)]. | as a result of the increase of relapsing fever cases in a rural area of west-rwanda, a study of ticks collected in the houses has been performed. ornithodoros moubata specimens were found in large amount. in patients, fever is the most frequent symptom. serological tests performed in the surrounding area of patients with borrelia in the blood are often positive, this confirming the ancient existence of the disease among inhabitants. | 1991 | 2072849 |
| yolk degradation in tick eggs: i. occurrence of a cathepsin l-like acid proteinase in yolk spheres. | in crude extracts of eggs of the soft tick ornithodoros moubata, maximum degradation of vitellin is at ph 3-3.5, whereas no proteolysis is detected at neutral or weakly acidic phs. acidic proteolysis is maintained at high level throughout embryonic development, and rapidly decreases in the larva, during the high phase of yolk degradation. proteinase, acid phosphatase, and n-acetylglucosaminidase are localized within the yolk spheres; these can be considered as lysosomal-like organelles containin ... | 1990 | 2134178 |
| yolk degradation in tick eggs: ii. evidence that cathepsin l-like proteinase is stored as a latent, acid-activable proenzyme. | cathepsin l-like proteinase found in the eggs of the tick ornithodoros moubata is latent during embryogenesis, but can be activated by acid treatment. in crude extracts as well as in partially purified fractions, activation requires reducing conditions and is inhibited by leupeptin, which indicates that it is mediated by a thiol proteinase, probably by the cathepsin l itself. latency disappears in vivo at the time of the acute phase of yolk digestion, which takes place during late embryonic deve ... | 1990 | 2134179 |
| tick anticoagulant peptide: kinetic analysis of the recombinant inhibitor with blood coagulation factor xa. | tick anticoagulant peptide (tap) is a 60 amino acid protein which is a highly specific inhibitor of human blood coagulation factor xa (fxa) isolated from the tick ornithodoros moubata [waxman, l., smith, d. e., arcuri, k. e., & vlasuk, g. p. (1990) science 248, 593-596]. due to the limited quantities of native tap, a recombinant version of tap produced in saccharomyces cerevisiae was used for a detailed kinetic analysis of the inhibition interaction with human fxa. rtap was determined to be a re ... | 1990 | 2271697 |
| tick anticoagulant peptide (tap) is a novel inhibitor of blood coagulation factor xa. | a low molecular weight serine protease inhibitor (tap) was purified from extracts of the soft tick, ornithodoros moubata. the peptide is a slow, tight-binding inhibitor, specific for factor xa (ki = 0.588 +/- 0.054 nm). the inhibitor also acts as an anticoagulant in several human plasma clotting assays in vitro. its amino acid sequence (60 residues) has limited homology to the kunitz-type inhibitors. however, unlike other inhibitors of this class, tap inhibits only factor xa. it had no effect at ... | 1990 | 2333510 |
| absence of ornithodoros moubata, the vector of african swine fever virus, from the main pig producing area of cameroon. | no evidence for the presence of soft ticks of the ornithodoros moubata complex was found during a survey of african swine fever carried out between 1985 and 1988 in the west province and southern parts of the north west and south west provinces of cameroon. the survey consisted of interviews of veterinary assistants and farmers, distribution of a questionnaire and tick searches both manually and with carbon dioxide traps. the absence of warthogs (phacochoerus aethiopicus) from these areas was al ... | 1990 | 2371751 |
| a study of african swine fever virus infected ticks (ornithodoros moubata) collected from three villages in the asf enzootic area of malawi following an outbreak of the disease in domestic pigs. | a detailed study was made in 1983-5 in three villages in mchinji district in the african swine fever (asf) enzootic area of malawi, following an outbreak of asf which affected all three villages. ticks of the ornithodoros moubata complex were collected from both pig sties and houses shortly after the outbreak, and approximately 24% contained asf virus. the proportion of ticks infected did not differ significantly in the three villages, or more surprisingly in different types of premises, and was ... | 1989 | 2737257 |
| [tick-borne relapsing fever in madagascar: an eradicated disease?]. | since about thirty years, no relapsing fever due to borrelia duttoni is recorded from madagascar. a survey was conducted in the formerly endemic area, between soalala and majunga, in order to collect data on possible cases and to look if the vector, ornithodoros moubata is still present. no mention of the disease was recorded; all ornithodoros seem to have completely disappeared in the area, without any clear reason. however, a few o. moubata specimens were recorded from piggeries in mahasolo, 1 ... | 1989 | 2743524 |
| an experimental assessment of the tampan tick ornithodoros moubata as vector of hepatitis b virus. | wild-caught and colonized tampan ticks, ornithodoros moubata (murray), were fed on hepatitis b virus (hbv)-positive blood-means in a series of four experiments. hepatitis b surface antigen (hbsag) persisted in nymphal and adult ticks for up to 779 days, while the epsmark antigen (hbeag) persisted in mature nymphs up to 13 days, in adult males up to 11 days and in adult females up to 16 days. hbsag was transmitted trans-stadially through two moults during the life cycle but transovarial transmiss ... | 1987 | 2979553 |
| host immunoglobulin g titre and antibody activity in haemolymph of the tick, ornithodoros moubata. | immunoglobulin g (igg) in tick haemolymph was analysed immunochemically and biochemically for its antigenicity, antibody activity and relative concentration in a soft tick, ornithodoros moubata (murray) sensu walton 1962 (acari: argasidae). ouchterlony immunodiffusion tests showed that haemolymph from a tick engorged on rabbit igg (or human igg) through an artificial membrane, reacted with anti-rabbit igg (anti-human igg) but not with anti-human igg (anti-rabbit igg). this indicates that haemoly ... | 1987 | 2979557 |
| potential for mechanical transmission of human immunodeficiency virus by the hut tampan, ornithodoros moubata. | | 1988 | 3185346 |
| genetic diversity of african swine fever virus isolates from soft ticks (ornithodoros moubata) inhabiting warthog burrows in zambia. | the genomes of african swine fever virus isolates collected from soft ticks (ornithodoros moubata) inhabiting warthog burrows in four areas of zambia were compared by restriction enzyme site mapping. isolates from different areas showed considerable diversity. the regions of genomes that differed between isolates were distributed throughout the virus genome, although some more conserved regions were identified, such as the right-hand third of the genome. the genomes of seven isolates from neighb ... | 1988 | 3199101 |
| a new method for determining vitellogenin in hemolymph of female ornithodoros moubata (acari: argasidae). | | 1988 | 3204631 |
| the distribution of african swine fever virus isolated from ornithodoros moubata in zambia. | african swine fever (asf) has been reported in the eastern province of zambia since 1912 and is now considered to be enzootic there. a survey of the distribution of asf virus in zambia was carried out by virus isolation from ornithodoros moubata ticks collected from animal burrows in national parks and game management areas in northern, eastern, central and southern zambia. asf virus was isolated from ticks in all areas examined. the prevalence of infection in o. moubata was between 0.4% in sout ... | 1988 | 3215286 |
| studies on susceptibility of ornithodoros moubata as vector of dipetalonema viteae (filariodea). | | 1988 | 3256567 |
| reduced oviposition in ornithodoros moubata (acari: argasidae) fed on tick-sensitized and vitellin-immunized rabbits. | | 1988 | 3357172 |
| isolation of african swine fever virus from ticks of the ornithodoros moubata complex (ixodoidea: argasidae) collected within the african swine fever enzootic area of malawi. | ticks of the ornithodoros moubata complex were collected from domestic pig sties and dwelling houses, and from a warthog habitat, and tested for the presence of african swine fever (asf) virus. collections were made in 9 of the 24 districts of malawi, these being primarily the districts in which o. moubata is most numerous. asf virus was isolated from ticks collected in both domestic pig sties and houses in certain villages in mchinji district where asf outbreaks had recently occurred. mchinji d ... | 1988 | 3402546 |
| metabolism of ecdysteroids in the female tick amblyomma hebraeum (ixodoidea, ixodidae): accumulation of free ecdysone and 20-hydroxyecdysone in the eggs. | [3h]-20-hydroxyecdysone ([3h]-20e) injected into amblyomma hebraeum females 7 days before the beginning of oviposition, viz. at the beginning of vitellogenesis, was converted to 3 polar peaks of unknown nature called 1, 2 and 3, and to apolar conjugates ap1, ap2 and ap3. ap2 have the same retention times as the esters of 20e with long chain fatty acids described in ornithodoros moubata (diehl et al. 1985). however, principally unmetabolized 20e was incorporated into the ovaries, and 16% of the i ... | 1987 | 3693624 |
| development and mortality of ornithodoros moubata after feeding through an artificial membrane. | high mortality rates have often been observed when artificial feeding techniques are used for colony maintenance of ornithodoros moubata. such fatalities can be readily controlled by addition of antibiotics to the feeding medium without apparent toxicity to ticks. comparative results show that for maintaining colonies of o. moubata artificial feeding techniques can be as efficient as direct feeding on swine--the primary hosts of these argasids. | 1986 | 3705178 |
| the distribution of ticks of the ornithodoros moubata complex (ixodoidea: argasidae) in malawi, and its relation to african swine fever epizootiology. | the distribution of ticks of the ornithodoros moubata complex in different habitats in malawi, particularly pigsties and houses, was established from a four-phase survey undertaken between 1982 and 1985. the first phase consisted of preliminary interviews, the second phase consisted of a questionnaire to veterinary assistants (vas) in rural areas, the third involved tick collections by vas and the fourth involved both interviews and tick collections by members of the central veterinary laborator ... | 1986 | 3734435 |
| metabolism of [3h]ecdysone by isolated tissues of the female ixodid tick amblyomma hebraeum (ixodoidea; ixodidae). | malpighian tubules, gut, ovaries and carcasses of the adult female tick amblyomma hebraeum were incubated in vitro in the presence of 2 microm [3h]ecdysone. organs and media were separately extracted after 6, 24 and 48 h incubations and the patterns of ecdysone metabolites were analyzed by hplc. esterase-susceptible apolar metabolites similar to the ap2 already described in the soft tick ornithodoros moubata and thus presumably corresponding to the same conjugates (c-22 esters with fatty acids) ... | 1986 | 3758475 |
| ornithodoros moubata: spermateleosis and secretory activity of the sperm. | cytological aspects of spermateleosis in the tick ornithodoros moubata were studied by electron microscopy. during spermateleosis, detachment of the operculum from the outer sheath of the prospermium results from the fusion of the plasma and the cisternal membranes. the fusion occurs between the shoulder of the acrosomal vesicle and the electron-dense layer of the operculum. a factor inducing vitellogenesis and egg-laying is secreted by the sperm cell after spermateleosis, and begins after the c ... | 1985 | 3908135 |
| ornithodoros moubata: host immunoglobulin g in tick hemolymph. | hemolymph proteins of a soft tick, ornithodoros moubata, were analyzed immunochemically and biochemically. the components of tick hemolymph proteins were shown to be totally different from the host (rabbit) serum proteins by polyacrylamide gel electrophoresis with sodium dodecyl sulfate and coomassie blue or silver stain. however, in the hemolymph of ticks engorged from rabbits immunoglobulin g was detected by immunoblotting analysis with goat anti-rabbit immunoglobulin g. the concentration of r ... | 1985 | 3935474 |
| use of a silicone membrane feeding technique in the laboratory maintenance of a colony of ornithodoros moubata. | adult ornithodoros moubata from a laboratory colony were fed on mice or through natural or artificial membranes on pig blood. the rate of feeding and its efficiency as assessed by fecundity were markedly superior when membranes rather than live mice were used. artificial silicone membranes offer major advantages of both convenience and economy over alternative membranes in the maintenance of soft tick colonies. | 1985 | 3992670 |
| effect of oxytetracycline on the growth curve of rickettsia prowazekii in the organism of the body louse (pediculus humanus corporis l.) and ornithodoros moubata tick (murray). | | 1974 | 4216445 |
| sexual transmission of african swine fever virus in the tick, ornithodoros moubata porcinus, walton. | | 1974 | 4417657 |
| the localization of african swine fever virus in the tick ornithodoros moubata porcinus. | | 1972 | 4564455 |
| intrahemocoelic infection of ticks ornithodoros moubata (murray) due to rickettsia prowazeki and the influence of some antibiotics on growth curve of this bacteria. | | 1972 | 4634100 |
| the influence of temperature on the course of experimental infection of ornithodoros moubata (murray) due to yersinia pseudotuberculosis. | | 1972 | 4660762 |
| the growth of yersinia pseudotuberculosis in artificially infected ornithodoros moubata (murray) ticks in dependence on their developmental stage. | | 1972 | 4660763 |
| [experiments on the transmission of toxoplasma gondii in various developing stages of ornithodoros moubata]. | | 1970 | 5426824 |
| experimental infection of the argasid tick, ornithodoros moubata porcinus, with african swine fever virus. | | 1970 | 5475061 |
| transovarial infection with african swine fever virus in the argasid tick, ornithodoros moubata porcinus, walton. | | 1970 | 5532269 |
| african swine fever virus in ticks (ornithodoros moubata, murray) collected from animal burrows in tanzania. | | 1969 | 5813153 |
| the sex chromatin body and its importance for the demonstration of heterochromosomal conditions in ornithodoros moubata (murray, 1877). | | 1966 | 5967509 |
| [immune response of rabbit to repeated infestations by ornithodoros moubata murray females: its influence on the biology of tick (author's transl)]. | antibodies against salivary gland tissues of the argasid tick, ornithodoros moubata, were detected by indirect immunofluorescence in rabbits repeatedly fed on by ticks. this immune response appears to have little adverse affects on the biology of the tick; blood intake was found to be sometimes smaller and the feeding period somewhat longer. attachment to the host and oviposition were not adversely affected. there exists a linear relationship between a) the weight of unfed and engorged females, ... | 1981 | 6111918 |
| arthropod studies with rabies-related mokola virus. | a cell culture-adapted variant of the rabies-related mokola virus was demonstrated to replicate in inoculated aedes aegypti mosquitoes. replication was slow compared to many arboviruses in their vectors. maximum titers were not obtained until after approximately 6 weeks of extrinsic incubation. mokola virus underwent nine mosquito-mosquito passages at approximately monthly intervals and was thus maintained in insects for 340 days before terminating the study. virus antigen was detected by immuno ... | 1984 | 6385743 |
| [processes of bacterial l transformation and l form reversion in the body of argasid ticks]. | the experimental infection of tampan ticks (ornithodoros moubata) with the bacterial cultures of listeria monocytogenes and salmonella typhimurium, as well as with their l-forms, was carried out. these experiments demonstrated that both the l-transformation of bacteria and the reversion of their l-forms into the initial bacterial culture could occur in the body of the ticks. | 1983 | 6414200 |
| metabolism of ecdysteroids during the vitellogenesis of the tick ornithodoros moubata (ixodoidea, argasidae): accumulation of apolar metabolites in the eggs. | the fate of injected [3h]ecdysone [( 3h]e) and 20-hydroxy-[3h]ecdysone [( 3h]20e) has been investigated in the female tick ornithodoros moubata (murray, 1877; sensu walton, 1962). when injected into fed mated vitellogenic females, [3h]e is converted into [3h]20e and two apolar classes of metabolites, ap1 and ap2. injected [3h]20e is directly converted into ap1 and ap2. ap2 is incorporated into the ovaries in a high proportion and at the end of the vitellogenic cycle represents about 25% of the t ... | 1984 | 6489734 |
| correlations between integument structure and ecdysteroid titers in fifth-stage nymphs of the tick, ornithodoros moubata (murray, 1877; sensu walton, 1962). | | 1982 | 7106547 |
| scanning electron microscopy of post-ejaculatory spermiogenesis in the tick ornithodoros moubata. | the final stages of spermiogenesis in ticks occur in the female genital tract. scanning electron microscopy was used to follow the morphologic changes that occur in the sperm during this post-ejaculatory spermiogenesis in the african soft tick, ornithodoros moubata, and to determine a time sequence for its occurrence in vivo. characteristic features of the maturing and mature cell described include (1) differentiation and detachment of the operculum, (2) changes in cell shape corresponding to di ... | 1982 | 7170714 |
| [effect of the lysozyme from ornithodoros moubata (argasidae) ticks on halprowia (chlamydia)]. | | 1981 | 7220082 |
| [immunobiological studies of the host-parasite relationship between rabbits and the tick ornithodoros moubata]. | | 1981 | 7271734 |
| [development of african ticks ornithodoros moubata during in vitro rearing]. | the suitability of in vitro-feeding for the laboratory rearing of ornithodoros moubata murray was tested by the development of about 3,000 first-stage nymphs to the adult stage. at intervals of 3 to 4 weeks defibrinated blood of sheep was fed to the ticks through a parafilm "m" membrane on an electric hot plate. on average 61% of the ticks were found engorged after the feeding. the highest rate of about 78% in the first nymphal stage decreased to about 45% in the fifth. the increase was highest ... | 1981 | 7305069 |
| [ultrastructural studies of haller's organ in the argasid ticks, ornithodoros moubata and alvenonasus lahorensis (argasidae)]. | the paper completes the series of morphological investigations of the main distant receptor organ in the ticks of the family argasidae by scanning and transmitting electron microscopy (balashov a. leonovich, 1977; leonovich, 1979) and considers descriptions of the fine structure of haller's organs of ornithodoid (o. moubata) and otobiinoid (a. lahorensis) types. the summarising of the data on haller's organ in argasids has enabled the author to suggest possible ways of evolution of this organ. a ... | 1980 | 7422346 |
| evidence of common and genus-specific epitopes on ornithodoros spp. tick (acari: argasidae) salivary proteins. | new zealand white rabbits were repeatedly infested with ornithodoros turicata (duges), ornithodoros talaje (guérin-méneville), and ornithodoros coriaceus (koch) at 2-wk intervals. blood samples were taken from each animal 10 d after each infestation and the titer of anti-tick antibody was determined by enzyme-linked immunosorbent assay. subsequent cross-reactivity studies demonstrated that the antitick antisera nonspecifically bound to salivary gland extract proteins prepared from several other ... | 1995 | 7544412 |
| effects of ingested phytoecdysteroids in the female soft tick ornithodoros moubata. | the effects of the ingestion of some phytoecdysteroids were studied in the soft tick ornithodoros moubata. supernumerary moulting and malformations of first leg pairs were obtained with 22-oxo-20-hydroxy-ecdysone, 20-hydroxyecdysone-22-acetate, and 20-hydroxyecdysone-22-benzoate. egg-yield was reduced with 20-hydroxyecdysone-22-acetate and carthamosterone. finally, drying-out of eggs was observed with carthamosterone and 22-deoxy-20,26-dihydroxyecdysone. in addition, we demonstrated that there i ... | 1995 | 7607304 |
| an inhibitor from the argasid tick ornithodoros moubata of cell adhesion to collagen. | an inhibitor of the adhesion of human platelets to collagen was identified in soluble extracts of the soft tick ornithodoros moubata and purified by four chromatographic steps. the isolated inhibitor, tai (tick adhesion inhibitor), is a approximately 15-kda protein that completely blocks the adhesion of platelets to collagen-coated microtiter plates with an ic50 of 8 nm. in the same concentration range it does not inhibit collagen-induced platelet aggregation or platelet adhesion to fibrinogen a ... | 1995 | 7695604 |
| acanthocheilonema viteae: rational design of the life cycle to increase production of parasite material using less experimental animals. | the maintenance of the life cycle of acanthocheilonema viteae is described with the aim to increase the production of parasite material using less experimental animals. the filaria was maintained in jirds (meriones unguiculatus) and in soft ticks (ornithodoros moubata). the optimal infection dosis for jirds was 80 infective larvae (l3). the mean worm number in groups of animals varied between 18 and 30 adult worms. a stable microfilaremia developed and only few animals developed pathological alt ... | 1995 | 7780447 |
| nmr solution structure of the recombinant tick anticoagulant protein (rtap), a factor xa inhibitor from the tick ornithodoros moubata. | the solution structure of the recombinant tick anticoagulant protein (rtap) was determined by 1h nuclear magnetic resonance (nmr) spectroscopy in aqueous solution at ph 3.6 and 36 degrees c. rtap is a 60-residue protein functioning as a highly specific inhibitor of the coagulation protease factor xa, which was originally isolated from the tick ornithodoros moubata. its regular secondary structure consists of a two-stranded antiparallel beta-sheet with residues 22-28 and 32-38, and an alpha-helix ... | 1994 | 7925983 |
| disagregin is a fibrinogen receptor antagonist lacking the arg-gly-asp sequence from the tick, ornithodoros moubata. | a platelet aggregation inhibitor was identified in the salivary gland of the tick ornithodoros moubata and isolated by gel filtration and reverse phase high pressure liquid chromatography. the purified inhibitor is a approximately 6-kda protein, which we have named disagregin. it inhibits adp-stimulated platelet aggregation in plasma with an ic50 = 104 +/- 17 nm. disagregin also inhibits platelet aggregation induced by other agonists, including collagen, epinephrine, platelet-activating factor, ... | 1994 | 8120028 |
| metabolism of [3h]-ecdysone in embryos and larvae of the tick ornithodoros moubata. | the fate of [3h]-ecdysone ([3h]-e) was investigated in hanging drop cultures of embryos and larvae of the tick ornithodoros moubata using hplc. the hormone was metabolized more slowly during described periods of increasing endogenous ecdysteroid (es) titers than during periods of low titers except for young embryos. three different classes of metabolites were produced: 1) apolar products (ap) corresponding to c-22 fatty acid ester conjugates of e and, in some cases, of 20-hydroxyecdysone (20e), ... | 1993 | 8318702 |
| isolation of an inhibitor selective for collagen-stimulated platelet aggregation from the soft tick ornithodoros moubata. | soluble extracts from the soft tick ornithodoros moubata were found to inhibit collagen-, adp-, and thrombin-stimulated platelet aggregation. one inhibitory component was purified to homogeneity by a combination of gel filtration, ion-exchange, and reverse phase high pressure liquid chromatography. the purified activity, named moubatin, is a protein of molecular weight 17,000 and it inhibits the aggregation of washed human platelets stimulated by collagen with an ic50 of approximately 50 nm in t ... | 1993 | 8449906 |
| cloning of the cdna and expression of moubatin, an inhibitor of platelet aggregation. | moubatin, a new type of specific inhibitor of collagen-induced platelet aggregation, has been isolated from the soft tick ornithodoros moubata (waxman, l., and connolly, t. m. (1993) j. biol. chem. 268, 5445-5449). a polymerase chain reaction-generated hybridization probe, produced using primers based on moubatin protein sequence, identified phage containing the entire cdna sequence of moubatin. analysis of the predicted amino acid sequence yielded a mature protein of 156 amino acids with a puta ... | 1993 | 8449907 |
| evaluation of mechanical transmission of hiv by the african soft tick, ornithodoros moubata. | to assess the ability of the african hut tampan, ornithodoros moubata, to mechanically transmit hiv-1 and to re-appraise hiv-1 infectivity in an arthropod cell line at 28 and 35 degrees c. | 1993 | 8471196 |
| a study of the vaccinal value of various extracts of concealed antigens and salivary gland extracts against ornithodoros erraticus and ornithodoros moubata. | on pig farms, elimination of the argasid ticks acting as reservoirs and vectors for african swine fever greatly favours the eradication of this disease. the elimination of ornithodoros erraticus involves many problems, most of which could be easily solved by the development of an anti-o. erraticus vaccine. with a view to developing this vaccine, we have tested the protective value of the immune response induced in swine by seven 'concealed' antigens and one soluble salivary gland extract. the la ... | 1995 | 8644449 |
| the ornithodorin-thrombin crystal structure, a key to the tap enigma? | ornithodorin, isolated from the blood sucking soft tick ornithodoros moubata, is a potent (ki = 10(-12) m) and highly selective thrombin inhibitor. internal sequence homology indicates a two domain protein. each domain resembles the kunitz inhibitor basic pancreatic trypsin inhibitor (bpti) and also the tick anticoagulant peptide (tap) isolated from the same organism. the 3.1 a crystal structure of the ornithodorin-thrombin complex confirms that both domains of ornithodorin exhibit a distorted b ... | 1996 | 8947023 |
| endosymbionts of ticks and their relationship to wolbachia spp. and tick-borne pathogens of humans and animals. | the presence, internal distribution, and phylogenetic position of endosymbiotic bacteria from four species of specific-pathogen-free ticks were studied. these included the hard ticks ixodes scapularis (the black-legged tick), rhipicephalus sanguineus (the brown dog tick), and haemaphysalis longicornis and the african soft tick ornithodoros moubata. pcr assays for bacteria, using two sets of general primers for eubacterial 16s and 23s rrna genes (rdnas) and seven sets of specific primers for wolb ... | 1997 | 9327557 |
| antigens of interest for the diagnosis of parasitism in pigs by ornithodoros erraticus and ornithodoros moubata. | we show by sodium dodecyl sulfate polyacrylamide gel electrophoresis and western blot that the composition of the soluble extracts of salivary glands (sge-2) of ornithodoros erraticus and ornithodoros moubata is similar to that of the saliva (pilocarpine-induced), and that the extracts are a valid source of antigens for the detection of anti-argasid antibodies. it is also shown that the sge-2s do not vary qualitatively with the developmental stage, physiological status, or sex of the ticks. the ... | 1997 | 9379286 |
| the interaction of disagregin with the platelet fibrinogen receptor, glycoprotein iib-iiia. | disagregin, a 6 kda protein isolated from salivary glands of the tick ornithodoros moubata, is a potent and selective inhibitor of fibrinogen dependent platelet aggregation and of the adhesion of platelets to fibrinogen (karczewski et al. (1994) j. biol. chem. 269, 6702-6708). in the current study the interaction of disagregin with purified glycoprotein iib-iiia (gpiib-iiia) was examined. biotin-labeled disagregin (b-disagregin) bound to gpiib-iiia immobilized on the surface of the elisa plate. ... | 1997 | 9434779 |
| a nonessential african swine fever virus gene uk is a significant virulence determinant in domestic swine. | sequence analysis of the right variable genomic region of the pathogenic african swine fever virus (asfv) isolate e70 revealed a novel gene, uk, that is immediately upstream from the previously described asfv virulence-associated gene nl-s (l. zsak, z. lu, g. f. kutish, j. g. neilan, and d. l. rock, j. virol. 70:8865-8871, 1996). uk, transcriptionally oriented toward the right end of the genome, predicts a protein of 96 amino acids with a molecular mass of 10.7 kda. searches of genetic databases ... | 1998 | 9444996 |
| african swine fever virus infection in the argasid host, ornithodoros porcinus porcinus. | the pathogenesis of african swine fever virus (asfv) infection in ornithodoros porcinus porcinus was examined in nymphal ticks infected with the asfv isolate chiredzi/83/1. at times postinfection (p.i.) ranging from 6 h to 290 days, ticks or dissected tick tissues were titrated for virus and examined ultrastructurally for evidence of virus replication. the asfv infection rate in ticks was 100% in these experiments, and virus infection was not associated with a significant increase in tick mortal ... | 1998 | 9499019 |
| deletion of a cd2-like gene, 8-dr, from african swine fever virus affects viral infection in domestic swine. | an african swine fever virus (asfv) gene with similarity to the t-lymphocyte surface antigen cd2 has been found in the pathogenic african isolate malawi lil-20/1 (open reading frame [orf] 8-dr) and a cell culture-adapted european virus, ba71v (orf ep402r) and has been shown to be responsible for the hemadsorption phenomenon observed for asfv-infected cells. the structural and functional similarities of the asfv gene product to cd2, a cellular protein involved in cell-cell adhesion and t-cell-med ... | 1998 | 9525608 |
| [new studies on natural inhibitors of proteolytic enzymes]. | new data on proteolytic enzyme inhibitors and mechanisms of their interaction with the enzymes are reviewed. in recent years, a number of new inhibitors comprising families earlier unknown have been described such as proteins from the parasitic nematode ascaris lumbricoides, ecotin from the periplasm of escherichia coli, proteins pmp-c and pmp-d from locust locusta migratoria, and hirustasin from the medicinal leech hirudo medicinalis. at the same time, some proteins that may be assigned to inhi ... | 1998 | 9661786 |
| the genome of melanoplus sanguinipes entomopoxvirus. | the family poxviridae contains two subfamilies: the entomopoxvirinae (poxviruses of insects) and the chordopoxvirinae (poxviruses of vertebrates). here we present the first characterization of the genome of an entomopoxvirus (epv) which infects the north american migratory grasshopper melanoplus sanguinipes and other important orthopteran pests. the 236-kbp m. sanguinipes epv (msepv) genome consists of a central coding region bounded by 7-kbp inverted terminal repeats and contains 267 open readi ... | 1999 | 9847359 |
| tetracycline therapy targets intracellular bacteria in the filarial nematode litomosoides sigmodontis and results in filarial infertility. | intracellular bacteria have been described in several species of filarial nematodes, but their relationships with, and effects on, their nematode hosts have not previously been elucidated. in this study, intracellular bacteria were observed in tissues of the rodent parasite litomosoides sigmodontis by transmission electron microscopy and by immunohistochemistry using antiendobacterial heat shock protein-60 antisera. molecular phylogenetic analysis of the bacterial 16s ribosomal rna gene, isolate ... | 1999 | 9884329 |
| cloning, nucleotide sequence and expression of the gene encoding factor xa inhibitor from the salivary glands of the tick, ornithodoros savignyi. | the n-terminal sequence of the competitive and slow tight-binding factor xa inhibitor (fxai; ki = 0.83 +/- 0.10 nm) isolated from the salivary glands of ornithodoros savignyi ticks (acari: argasidae) was employed to design a degenerate gene-specific primer (gsp) for 3'-rapid amplification of cdna ends (3'-race). the primer consisted of a sequence encoding for amino acid residues 5-11. a full-length gene was next constructed from the 3'-race product in a two-step pcr procedure and successfully ex ... | 1998 | 9890144 |
| invertebrate compounds acting on the hemostatic mechanism. | physiological secretions from some invertebrates have toxic effects on mammalian blood coagulation and fibrinolytic systems. some of these effects occur because the substances contained in the secretions resemble the components of the hemostatic system. some of the substances have been characterized, and have been found to have similar molecular weights or sequences, which may indicate a common ancestry. the components can be divided into five groups: antithrombic agents (group i); inhibitors an ... | 1999 | 10192653 |
| bacterioferritin a modulates catalase a (kata) activity and resistance to hydrogen peroxide in pseudomonas aeruginosa. | we have cloned a 3.6-kb genomic dna fragment from pseudomonas aeruginosa harboring the rpoa, rplq, kata, and bfra genes. these loci are predicted to encode, respectively, (i) the alpha subunit of rna polymerase; (ii) the l17 ribosomal protein; (iii) the major catalase, kata; and (iv) one of two iron storage proteins called bacterioferritin a (bfra; cytochrome b1 or b557). our goal was to determine the contributions of kata and bfra to the resistance of p. aeruginosa to hydrogen peroxide (h2o2). ... | 1999 | 10368148 |
| [peptides as inhibitors of thrombin coagulation activity and of thrombocyte aggregation]. | the analysis of literature and our own data of regulatory peptides influence on the blood coagulation system is presenting. various natural and synthetic peptides inhibit the activity of thrombin and platelet aggregation. direct specific inhibitors of thrombin are peptides developed on the base of d-phe-pro-arg sequence. strong specific inhibitors of the prothrombinase complex factor xa were isolated from tissues and saliva of the blood-sucking organisms. these inhibitors decrease thrombin gener ... | 1999 | 10420478 |
| african swine fever virus replication in the midgut epithelium is required for infection of ornithodoros ticks. | although the malawi lil20/1 (mal) strain of african swine fever virus (asfv) was isolated from ornithodoros sp. ticks, our attempts to experimentally infect ticks by feeding them this strain failed. ten different collections of ornithodorus porcinus porcinus ticks and one collection of o. porcinus domesticus ticks were orally exposed to a high titer of mal. at 3 weeks postinoculation (p.i.), <25% of the ticks contained detectable virus, with viral titers of <4 log(10) 50% hemadsorbing doses/ml. ... | 1999 | 10482612 |
| purification and characterization of the lysozyme from the gut of the soft tick ornithodoros moubata. | the gut of the adult soft ticks ornithodoros moubata displays high lytic activity against the bacteria micrococcus luteus. the activity differed in the range of two orders of magnitude among individual animals and increased on average 4 fold during the first week following ingestion. in homogenates of first instar nymphs the activity was much lower increasing exponentially as nymphs neared the first molt. the protein responsible for this activity was purified out of gut contents of adult ticks b ... | 1999 | 10560138 |
| an african swine fever virus erv1-alr homologue, 9gl, affects virion maturation and viral growth in macrophages and viral virulence in swine. | the african swine fever virus (asfv) genome contains a gene, 9gl, with similarity to yeast erv1 and alr genes. erv1 has been shown to function in oxidative phosphorylation and in cell growth, while alr has hepatotrophic activity. 9gl encodes a protein of 119 amino acids and was highly conserved at both nucleotide and amino acid levels among all asfv field isolates examined. monospecific rabbit polyclonal antibody produced to a glutathione s-transferase-9gl fusion protein specifically immunopreci ... | 2000 | 10627538 |
| characterization of an alpha-macroglobulin-like glycoprotein isolated from the plasma of the soft tick ornithodoros moubata. | we report the identification of the first representative of the alpha-2-macroglobulin family identified in terrestrial invertebrates. an abundant acidic glycoprotein was isolated from the plasma of the soft tick ornithodoros moubata. its molecular mass is about 420 kda in the native state, whereas in sds/page it migrates as one band of 190 kda under nonreducing conditions and a band of 92 kda when reduced. chemical deglycosylation reveals that it is composed of two different subunits, designated ... | 2000 | 10632716 |
| immunity reduces reservoir host competence of peromyscus leucopus for ehrlichia phagocytophila. | infection with ehrlichia phagocytophila in white-footed mice is transient and followed by a strong immune response. we investigated whether the presence of acquired immunity against e. phagocytophila precludes white-footed mice from further maintenance of this agent in nature. mice were infected with e. phagocytophila via tick bite and challenged either 12 or 16 weeks later by ixodes scapularis nymphs infected with the same agent. xenodiagnostic larvae fed upon each mouse simultaneously with cha ... | 2000 | 10678968 |
| isolation and characterization of dorin m, a lectin from plasma of the soft tick ornithodoros moubata. | a lectin with high hemagglutinating activity, which we have named dorin m, was identified in the plasma of the soft tick ornithodoros moubata. the activity of the plasma lectin could be efficiently inhibited by sialic acid, n-acetyl-d-hexosamines and sialoglycoproteins. dorin m was purified to homogeneity using two different isolation systems: affinity chromatography on a column of bovine submaxillary mucin conjugated to sepharose 4b with specific elution by n-acetyl-d-glucosamine and chromatogr ... | 2000 | 10732987 |
| immune responses of the argasid tick ornithodoros moubata moubata induced by infection with the filarial worm acanthocheilonema viteae. | investigations were undertaken to determine whether the tick ornithodoros moubata moubata mounted a detectable immune response to primary and secondary infections with acanthocheilonema viteae. uninfected control tick survival rate was 70%, but only 45% in the primary infection group. post-secondary infection survival rate (82%) was comparable to controls, indicating that these selected ticks had some protective advantage. mean a. viteae infective larvae recovery from ticks with secondary infect ... | 2000 | 10953223 |
| serodiagnosis of louse-borne relapsing fever with glycerophosphodiester phosphodiesterase (glpq) from borrelia recurrentis. | human louse-borne relapsing fever occurs in sporadic outbreaks in central and eastern africa that are characterized by significant morbidity and mortality. isolates of the causative agent, borrelia recurrentis, were obtained from the blood of four patients during a recent epidemic of the disease in southern sudan. the glpq gene, encoding glycerophosphodiester phosphodiesterase, from these isolates was sequenced and compared with the glpq sequences obtained from other relapsing-fever spirochetes. ... | 2000 | 11015364 |
| nitrophorins and related antihemostatic lipocalins from rhodnius prolixus and other blood-sucking arthropods. | recent gene sequence and crystal structure determinations of salivary proteins from several blood-sucking arthropods have revealed an unusual evolutionary relationship: many such proteins derive their functions from lipocalin protein folds. many blood-sucking arthropods have independently evolved the ability to overcome a host organism's means of preventing blood loss (called hemostasis). most blood feeders have proteins that induce vasodilation, inhibit blood coagulation, and reduce inflammatio ... | 2000 | 11058753 |
| effects of infection of the tick ornithodoros moubata with african swine fever virus. | the effects of infection with african swine fever virus (asfv) on adult and nymphal ornithodoros moubata murray (ixodoidea, argasidae) ticks were examined. three groups of ticks were used, an uninfected control group, one group infected with the vic t90/1 isolate of asfv and another group infected with the liv 13/33 isolate of asfv. infection with asfv did not affect the oviposition rates of infected ticks when compared with uninfected ticks. there was no difference between infected and uninfect ... | 2000 | 11129698 |
| african swine fever virus multigene family 360 and 530 genes are novel macrophage host range determinants. | pathogenic african swine fever virus (asfv) isolates primarily target cells of the mononuclear-phagocytic system in infected swine and replicate efficiently in primary macrophage cell cultures in vitro. asfvs can, however, be adapted to grow in monkey cell lines. characterization of two cell culture-adapted viruses, ms16 and ba71v, revealed that neither virus replicated in macrophage cell cultures. cell viability experiments and ultrastructural analysis showed that infection with these viruses r ... | 2001 | 11238833 |
| two isoforms of a member of the arthropod defensin family from the soft tick, ornithodoros moubata (acari: argasidae). | we previously purified and determined the partial amino acid sequence of a 4 kda peptide having high homology with scorpion defensin from the hemolymph of adult fed female soft ticks, ornithodoros moubata. in this study, the full length sequences of two defensin isoforms were obtained. deduced amino acid sequences reveal a precursor protein of 73 amino acid residues with a mature portion consisting of 37 amino acid residues. this mature peptide contains six cysteine residues conserved in the sam ... | 2001 | 11378409 |