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1.
Fine binding specificities to Ascaris suum and A. lumbricoides antigens of the sera from patients with probable visceral larva migrans (VLM) due to A. suum infection were examined. Although multiple-dot enzyme-linked immunosorbent assay (ELISA) was found to be useful for the primary screening of patients, identification of the responsible species was sometimes difficult due to extensive cross reactions with other ascarid parasite antigens. Fine resolution to determine the causative pathogen was obtained by a rather classical Ouchterlony's double immunodiffusion test. The difference in the binding of the patients' sera to A. suum and A. lumbricoides antigens was also demonstrated by an inhibition ELISA. The patients' antibodies bound with higher avidity to the A. suum antigen than to the A. lumbricoides and Toxocara canis antigens. Combination of at least two different immunological assay methods is recommended for the diagnosis of VLM due to ascarid parasites.  相似文献   

2.
A colony of Japanese macaques (Macaca fuscata fuscata) kept by a safari-style zoo in Japan experienced 9 sporadic cases of fatal neurological diseases, such as epilepsy and posterior paralysis, during the 12 yr from 1989 to 2001. This macaque colony consisted of approximately 30 animals, on average, during this period, and the macaques shared their living space with II American black bears (Ursus americanus) harboring zoonotic roundworms (Baylisascaris transfuga). Close to this enclosure, a cote for 2-3 raccoons (Procyon lotor) was placed, and raw sewage from this cote ran into a shallow drain in the area for macaques and bears. However, fecal examinations in recent years did not detect the infection of raccoons with zoonotic roundworms (Baylisascaris procyonis). Postmortem histological examination of the latest 2 ill macaques detected multifocal malacia in the brain; 2 ascarid larvae of 60 microm maximum width were encapsulated in the cerebrum and lungs of 1 of the animals. To determine the causative ascarid species of the fatal larva migrans, we analyzed 2 additional encapsulated Baylisascaris larvae collected from formalin-fixed lungs by morphological and molecular approaches. This sporadic outbreak is the second record of Baylisascaris larva migrans in animals in Japan.  相似文献   

3.
The giant panda is a global symbol of wildlife conservation that is threatened by historic and current habitat loss. Despite a great deal of research on the physiology, reproductive biology, and diet of pandas in the wild and in captivity, there is little information on wild panda mortality. Here we integrate previously unavailable data on the mortality of wild pandas. We report on three recent phases of panda mortality: deaths due to bamboo flowering in the 1970s and 1980s, surprisingly extensive poaching in the 1980s and 1990s, and a parasitic infection over the past few years. Our analyses suggest that the current most significant threat to wild panda survival is disease due to extraintestinal migration (visceral larval migrans) by an ascarid nematode. We demonstrate that the probability of death of wild pandas being caused by this disease increased significantly between 1971 and 2005 and discuss the possible factors leading to the emergence of this disease. Electronic Supplementary Material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

4.
A syndrome of progressive neurological signs was noticed in rabbits (Oryctolagus cuniculus) kept in a small wildlife park in mid-July 2000. Three out of 12 common raccoons (Procyon lotor) kept in this park were infected with Baylisascaris procyonis, and the larvae were found from affected rabbits. This outbreak is the first proven B. procyonis larva migrans in Japan, and the potential risk of serious zoonosis by this ascarid species should be considered by pet owners, veterinarians, physicians and public health authorities in this country as in North America where raccoons are endemic.  相似文献   

5.
Chickens are considered to act as paratenic hosts for agents, Toxocara canis, T. cati and Ascaris suum; which cause ascarid larva migrans syndrome (ascarid LMS) in humans. In addition, they are the definitive host for Ascaridia galli, considered not to be infective for humans. All ascarid parasites can have a high homology of antigenicity, leading to cross-reactivity in serodiagnostic assays. This study was conducted to establish a procedure for the serological detection of those roundworm infections in chickens.Twenty-five male Julia chickens were divided into five groups (n = 5); T. canis-, T. cati-, Ascaris suum- and Ascaridia galli-infected, and an uninfected control group. In Ascaris suum-soluble worm antigen preparation (As-SWAP) ELISA, all infected groups showed an elevation of anti-ascarid antibodies, indicating the usefulness of As-SWAP as a screening antigen for the detection of ascarid infections. For infecting species identification, T. canis-excretory/secretory (Tc-ES) and Ascaris suum-ES (As-ES) antigen ELISA were conducted by serial dilution sera. Toxocara spp.-infected sera showed stronger binding to Tc-ES than As-ES, while Ascaris suum and Ascaridia galli-infected sera bound to As-ES more strongly than Tc-ES. To discriminate between Ascaris suum and Ascaridia galli infection, sera were pre-incubated with Ascaridia galli-SWAP antigen and applied to Tc-ES and As-ES ELISAs. In this pre-adsorbed ES antigen ELISAs, only the Ascaris suum infected group showed positive binding to As-ES, resulting from the adsorption of cross-reactive antibodies in Ascaridia galli-infected sera. Finally, anti-Toxocara specific antibodies were confirmed by Tc-ES western blot (WB). Toxocara spp.-infected sera showed toxocariasis-specific band pattern in Tc-ES WB, while no specific band appeared on any strip incubated with Ascaris suum, Ascaridia galli-infected and uninfected sera.In conclusion, the serodiagnostic assays evaluated in this study are useful for the detection of ascarid infections in chickens.  相似文献   

6.
A fructose diphosphate aldolase has been isolated from ascarid muscle and crystallized by simple column chromatography and an ammonium sulfate fractionation procedure. It was found to be homogeneous on electrophoresis and Sephadex G-200 gel filtration. This enzyme has a fructose diphosphate/fructose 1-phosphate activity ratio close to 40 and specific activity for fructose diphosphate cleavage close to 11. Km values of ascarid aldolase are 1 × 10−6m and 2 × 10−3m for fructose diphosphate and fructose 1-phosphate, respectively. The enzyme reveals a number of catalytic and molecular properties similar to those found for class I fructose diphosphate aldolases. It has C-terminal functional tyrosine residues, a molecular weight of 155,000, and is inactivated by NaBH4 in presence of substrate. Data show the presence of two types of subunits in ascarid aldolase; the subunits have different electrophoretic mobilities but similar molecular weights of 40,000. Immunological studies indicate that the antibody-binding sites of the molecules of the rabbit muscle aldolase A or rabbit liver aldolase B are structurally different from those of ascarid aldolase. Hybridization studies show the formation of one middle hybrid form from a binary mixture of the subunits of ascarid and rabbit muscle aldolases. Hybridization between rabbit liver aldolase and ascarid aldolase was not observed. The results indicate that ascarid aldolase is structurally more related to the mammalian aldolase A than to the aldolase B.  相似文献   

7.
Baylisascaris procyonis is a large ascarid nematode found in the small intestine of raccoons (Procyon lotor). Infection with larvae of B. procyonis can produce visceral, ocular, and neural larval migrans in humans. Infected raccoons can shed millions of eggs a day in their feces. However, it is unknown whether eggs are consistently shed or whether eggs occur at irregular intervals by the population of female nematodes within a host. We trapped, infected, and collected daily fecal samples from 11 raccoons maintained in captivity. Eggs from B. procyonis were obtained from anterior, central, and posterior sections of raccoon feces, isolated by flotation, and quantified under 100× magnification. Naturally infected raccoons were collected and used as a comparison with the experimentally infected group. All raccoons in the experimental group (n=11) became infected with B. procyonis after consuming one infected mouse. Additionally, differential egg deposition rates were observed among individual raccoons from the experimental and naturally infected groups. Mean number of eggs per gram of feces (means±SE) was 16,563±4,321, which was less than previously reported for the species. However, no differences (F(2,30)=0.84, P=0.45) were noted in mean number of eggs per gram of feces among fecal sections. Wildlife biologists, veterinarians, health officials, and researchers of B. procyonis should collect daily fecal samples for a minimum of 3 days before identifying a raccoon as negative for B. procyonis infection. However, it does not matter where within the fecal matter the sample is obtained.  相似文献   

8.
The pyruvate dehydrogenase complex (PDC) from muscle of the adult parasitic nematode Ascaris suum plays a unique role in its anaerobic mitochondrial metabolism. Resolution of the intact complex in high salt dissociates the pyruvate dehydrogenase subunit but leaves the dihydrolipoyl dehydrogenase subunit (E3) and two other proteins with apparent M(r)s of 45 and 43 kDa bound to the dihydrolipoyl transacetylase (E2) core. These proteins are not observable on Coomassie brilliant blue-stained gels of other eukaryotic PDCs, but the 45-kDa protein is similar in apparent M(r), pI, and sensitivity to trypsin to the Kb subunit of the bovine kidney PDH alpha kinase. Acetylation of the ascarid PDC with [2-14C]pyruvate under conditions designed to maximize the incorporation of label into protein yielded only a single radiolabeled subunit, E2. These results confirm earlier reports that the ascarid PDC lacks protein X, an integral component recently identified in other eukaryotic PDCs. About 1.6 to 1.8 mol of 14C was incorporated/mole of E2, suggesting that the ascarid E2 contained two lipoly-bearing domains. Domain mapping of the 14C-acetylated ascarid E2 by limited tryptic digestion identified two lipoyl-bearing fragments with apparent M(r)s of 50 and 34 kDa and two core fragments with apparent M(r)s of 46 and 30 kDa. The ascarid E2 domain structure appears to be similar to that of other E2s. However, it appears that the subunit-binding domain (E2B) of the ascarid E2 may be significantly larger or be flanked by larger than normal interdomain regions. An enlarged E2B domain may be necessary to accommodate the additional binding of E3 to the E2 subunit in the ascarid complex, in the absence of protein X.  相似文献   

9.
The effects of 6 months' combined therapy with phenformin and an anabolic steroid were compared in patients with thrombophlebitis migrans (12 patients) and those with superficial thrombophlebitis (15 patients). In both groups of patients an increase in blood fibrinolytic activity, and "capacity" decrease in platelet adhesiveness, plasma fibrinogen, blood lipids, beta lipoproteins as well as serum cholesterol level were found. A statistically significant decrease in frequency of inflammations in patients with thrombophlebitis migrans occurred. In these patients a return of the previously low "fibrinolytic capacity" to normal values was observed. It seems that prolonged activation of fibrinolysis by means of phenformin and an anabolic steriod may be of value in the prophylaxis of venous thrombosis especially thrombophlebitis migrans.  相似文献   

10.
Raccoon roundworms (Baylisascaris procyonis) and other Baylisascaris species cause patent or latent larva migrans (LM) in a variety of mammals and birds, including humans. It is not clear whether LM by Baylisascaris transfuga, roundworms of bears, is associated with clinical neurological disorders. To clarify this issue, ICR and BALB/c mice as well as Mongolian jirds (Meriones unguiculatus) were orally inoculated with 2,000-5,000 embryonated eggs of B. transfuga. In mice, the ascarid caused symptomatic LM of limited extent and duration, whereas the infection was fatal in jirds; i.e., they exhibited general signs such as severe depression and emaciation on days 8-11 postinfection (PI) and died, or they developed progressive and fatal neurological disorders after day 14 PI. Histological examination showed B. transfuga larvae in the brain of all mice and jirds examined, and the larvae collected from them developed to a size comparable with that of B. procyonis. There existed, however, critical differences in host reactions against larvae localized in the brain of mice and jirds; B. transfuga larvae found in mice were surrounded by granulomatous reactions and immobilized, whereas larvae found in jirds were free from any host reaction and mobile, causing extensive malacia.  相似文献   

11.
European erythema migrans disease and related disorders   总被引:5,自引:0,他引:5  
European erythema migrans disease, lymphocytoma, and acrodermatitis chronica are a group of disorders associated with the bite of ixodid ticks. These disorders are now thought to be due to a single, or closely related, ixodid tick spirochetes. European erythema migrans disease closely resembles Lyme disease. Serological evaluation may help to separate spirochetal lymphocytoma from other pseudolymphomas of nonspirochetal origin and from lymphoma. Acrodermatitis chronica atrophicans, so far observed mainly in Europe, is presumably a late manifestation of this group of spirochetal disorders.  相似文献   

12.
To determine the incidence of physician-diagnosed Lyme disease in an endemic area of California, an active surveillance program was implemented in Lake, Mendocino, Sonoma, and southern Humboldt counties. More than 200 medical care providers were called monthly for their list of suspected cases of Lyme disease. Pertinent information was abstracted from the medical record of each patient. Of 153 cases of possible early Lyme disease ascertained from July 1991 to December 1992, 37% consisted of physician-diagnosed erythema migrans. Only 58% of erythema migrans rashes were at least 5 cm in diameter. An additional 43 patients had suspicious rashes not classified as erythema migrans. Of 166 patients with possible late-stage Lyme disease, 31% had specific clinical symptoms and 75% had a positive serologic test. With an incident case defined as physician-diagnosed erythema migrans of at least 5 cm in diameter, the annual incidence of Lyme disease in northwestern coastal California according to active surveillance only was 5.5 per 100,000. The rate of Lyme disease in California is substantially lower than that in the Atlantic northeastern United States. Many suspected cases of Lyme disease in this endemic area do not meet surveillance criteria, which are intentionally restrictive. Although some of the illnesses not meeting surveillance criteria may be due to infection with Borrelia burgdorferi, it appears that Lyme disease is being overdiagnosed in this area.  相似文献   

13.
Baylisascaris procyonis is well recognized as a cause of visceral (VLM), ocular, and neural (NLM) larva migrans in birds and mammals, including man. A study of the prevalence of larva migrans in free-ranging wildlife associated with raccoon latrines as well as a retrospective study of wildlife mortalities with neurological disease was conducted in 2000 in Orange County, California. Eighty-seven birds of 18 species and 64 mammals of 8 species were found to have NLM or VLM or both. NLM clinical signs included convulsions, torticollis, opisthotonus, head-tilts, circling, ataxia, paralysis, and visual defects. NLM lesions were characterized by focally disseminated, frequently linear, "tracklike" areas of parenchymal degeneration with varying degrees of astrocytosis in the white matter of the cerebrum, cerebellum, brain stem, and spinal cord. Larvae were rarely found in these lesions but were rather isolated in the brain-spinal cord parenchyma. At least 1 larva was isolated by digestion from each case of NLM and identified as Baylisascaris sp., most likely B. procyonis. VLM lesions consisted of granulomatous reactions surrounding intact or degenerative larvae in the parenchyma of the liver, kidney, diaphragm, and, occasionally, the lymph nodes. This report broadens the range of species of wild birds and mammals that have been found to be susceptible to larva migrans caused by B. procyonis and reaffirms the importance of raccoon latrine sites as contaminative foci for wildlife.  相似文献   

14.
Recombinant Fasciola cathepsin L-1 (rCatL1) was evaluated in enzyme-linked immunosorbent assay (ELISA) for the serodiagnosis of human fasciolosis in Japan. Quality characteristics of the test were accessed by receiver operating characteristic (ROC) analysis, with sera from fasciolosis patients (n = 10), patients with no evidence of parasitic infections (n = 29), and patients with other helminth infections (n = 119). Both the sensitivity and specificity of the test achieved 100% with the control samples. To test the performance of the assay in an authentic situation, 311 serum samples, which had been sent to our laboratory for the diagnosis of parasitic infections from January 2018 to February 2019, were re-assessed using the rCatL1 ELISA. In this case, the sensitivity of the rCatL1 ELISA was 100%, giving positive results to all fasciolosis sera (n = 7), and the specificity was 99.0%, in which three of the 304 non-fasciolosis samples were judged positive. Careful re-examination of the laboratory data and medical imaging of these three patients revealed that one of the patients, who had been diagnosed as having larva migrans syndrome, was judged to be infected with Fasciola, in addition to ascarid nematodes. Thus the true specificity of the assay in the authentic reached 99.3% (302/304). As the rCatL1 ELISA exhibited a highly significant positive likelihood ratio (152.0) and negative likelihood ratio (0.0), calculated from the 311 sample data, this rCatL1 ELISA can be used for routine screening and definitive diagnosis test for fasciolosis in reference laboratories.  相似文献   

15.
Acyl CoA dehydrogenase and electron-transfer flavoprotein have been isolated and partially purified from mitochondria of the anaerobic nematode, Ascarissuum. Dehydrogenase activity was greatest with 2-methylbutyryl CoA and the relative substrate specificities of the ascarid dehydrogenase(s) differ greatly from their mammalian counterparts. It appears that the ascarid dehydrogenase functions physiologically as a reductase, catalyzing the final step in the synthesis of branched-chain fatty acids. In fact, incubations of A. suum mitochondrial membranes with electron-transfer flavoprotein, 2-methylbutyryl CoA dehydrogenase, 2-methylcrotonyl CoA and NADH resulted in a substantial, rotenone-sensitive, 2-methylbutyrate synthesis. These results suggest that the ascarid electron-transport chain and at least two soluble mitochondrial proteins are involved in the NADH-dependent reduction of 2-methylcrotonyl CoA.  相似文献   

16.
Human toxocariasis is a helminthozoonosis due to the migration of Toxocara species larvae through human organism. Humans become infected by ingesting either embryonated eggs from soil (geophagia, pica), dirty hands or raw vegetables, or larvae from undercooked giblets. The diagnosis relies upon sensitive immunological methods (ELISA or western-blot) which use Toxocara excretory-secretory antigens. Seroprevalence is high in developed countries, especially in rural areas, and also in some tropical islands. The clinical spectrum of the disease comprises four syndromes, namely visceral larva migrans, ocular larva migrans, and the more recently recognized "common" (in adults) and "covert" (in children) pictures. Therapy of ocular toxocariasis is primarily based upon corticosteroids use, when visceral larva migrans and few cases of common or covert toxocariasis can be treated by anthelmintics whose the most efficient appeared to be diethylcarbamazine. When diagnosed, all of these syndromes require thorough prevention of recontamination (especially by deworming pets) and sanitary education.  相似文献   

17.
An enzyme-linked immunosorbent assay is described for the detection of serum antibodies to visceral larva migrans (Toxocariasis). Excretory-secretory antigens of the second-stage larvae of Toxocara canis were used as antigen to coat the polystyrene plates. With sera from patients high antibody titers were observed in both ocular and visceral disorders. Cross-reactions due to other parasitic infections could be excluded, including other migrating larval infections such as ascariasis, trichinellosis, strongyloidiasis, filariasis, and anisakiasis. In a small seroepidemiologic survey of healthy primary schoolchildren, a remarkably high percentage (7.1) reacted positively to this method. These children showed eosinophilia as compared to the seronegative group. The data were compared with those observed in other countries and the results prompt reconsideration of the significance of T. canis for public health.  相似文献   

18.
Laboratory-based surveillance of Lyme disease in Connecticut during 1984 and 1985 identified 3,098 persons with suspected Lyme disease; 1,149 were defined as cases. Lyme disease incidence in Connecticut towns ranged from none to 1,407 cases per 100,000 population in 1985. A comparison of 1985 data with data from 1977 epidemiologic studies indicated that incidence increased by 129 percent to 453 percent in towns previously known to be endemic for Lyme disease and that Lyme disease had spread northward into towns thought to be free of Lyme disease in 1977. Children aged five to 14 years had the highest incidence. Of persons with Lyme disease, 83 percent had erythema migrans, 24 percent had arthritis, 8 percent had neurologic sequelae, and 2 percent had cardiac sequelae. The distribution of symptoms was age-dependent: case-persons less than 20 years old were almost twice as likely to have arthritis than older case-persons (35 percent versus 18 percent). Of persons with arthritis, 92 percent of those less than 20 years of age, compared to 68 percent of older persons, did not have antecedent erythema migrans. We conclude that Lyme disease is increasing in incidence and geographic distribution in Connecticut. Of those with Lyme disease, children may be more likely than adults to develop arthritis and have it as their first major disease manifestation.  相似文献   

19.
Thick-shelled eggs of animal-parasitic ascarid nematodes can survive and remain infective in the environment for years. The present study evaluated a simple in vitro method and evaluation scheme to assess the relative effect of two species of soil microfungi, Pochonia chlamydosporia Biotype 10 and Purpureocillium lilacinum Strain 251 (Ascomycota: Hypocreales), on the development and survival of eggs of faecal origin of three ascarid species, Ascaridia galli (chicken roundworm), Toxocara canis (canine roundworm) and Ascaris suum (pig roundworm). Ascarid eggs were embryonated on water agar with or without a fungus, and the resulting viability of the eggs was evaluated on days 7, 14, 21, 28, 35 and 42 post exposure (pe) by observing eggs in situ. On days 7–42 pe, P. chlamydosporia had reduced the viability of A. galli and T. canis eggs by 64–86% and 26–67%. Corresponding reductions for P. lilacinum Strain 251 were only 15–29% and 4–28%. In contrast, A. suum eggs were extremely resistant to both fungi (2–4% reduction). The differences in results are likely due to different morphologies and chemistry of the egg shell of the three ascarid species. The current in vitro method and evaluation criteria allow for a simple, repeatable and non-invasive evaluation of the ovicidal effects of microfungi. This study demonstrates that P. chlamydosporia Biotype 10 may be utilised as a biocontrol agent to reduce A. galli and T. canis egg contamination of the environment.  相似文献   

20.
From three endemic locations of erythema chronicum migrans disease in North Rhine-Westphalia, Germany, we recovered 19 isolates of a spirochete from Ixodes ricinus ticks. The infection rate in adult ticks was 16 percent. The isolated spirochete is immunologically related to the Ixodes dammini spirochete, Borrelia duttoni, and Treponema pallidum. Using indirect immunofluorescence, the sera of 90 patients with erythema chronicum migrans disease showed antibody titers against the isolated spirochete, which correlated with the clinical course. Similarly, antibodies were demonstrated in the sera of 21 patients with acrodermatitis chronica atrophicans. These results suggest an etiologic role for the Ixodes ricinus spriochete in European erythema chronicum migrans disease.  相似文献   

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