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1.
Between 1988 and 1991, 644 serum samples were collected from 480 grizzly bears (Ursus arctos horribilis) and 40 black bears (Ursus americanus) from Alaska, United States of America, and were tested for selected canine viral infections and zoonoses. Antibody prevalence in grizzly bears was 0% for parvovirus, 8.3% (40/480) for distemper, 14% (68/480) for infectious hepatitis, 16.5% (79/480) for brucellosis, 19% (93/480) for tularaemia and 47% (225/478) for trichinellosis. In black bears, prevalence ranged from 0% for distemper and parvovirus to 27.5% for trichinellosis and 32% for tularaemia. Antibody prevalence for brucellosis (2.5%) and tularaemia (32%) were identical for grizzly bears and black bears from the geographical area of interior Alaska. Links between differences in prevalence and the origin of the grizzly bears were observed. Antibodies to canine distemper virus and infectious hepatitis virus were mainly detected in grizzly bears from Kodiak Island and the Alaskan Peninsula. Brucellosis antibodies were prevalent in grizzly bears from western and northern Alaska, whereas tularaemia antibodies were detected in grizzly bears from interior Alaska and the Arctic. There was a strong gradient for antibodies to Trichinella spp. from southern to northern Alaska. For most diseases, antibody prevalence increased with age. However, for several infections, no antibodies were detected in grizzly bears aged from 0 to 2 years, in contrast to the presence of those infections in black bears. Grizzly bears served as excellent sentinels for surveillance of zoonotic infections in wildlife in Alaska.  相似文献   

2.
Serum samples from 143 hunter-killed black bears were collected during the 1996 and 1997 black bear hunting seasons in eastern North Carolina. All samples were tested for antibodies to Toxoplasma gondii by the modified agglutination test. Antibodies to T. gondii were present in 120 of 143 (84%) bears. Females had significantly higher titers than males (Wilcoxon rank sums test, P = 0.045), and titers increased with age (Jonckheere test, P = 0.01). Samples collected during 1996 (n = 79) were tested for antibodies to Trichinella spiralis by enzyme-linked immunosorbent assay. No samples were positive for antibodies to T. spiralis.  相似文献   

3.
One hundred and twenty seven patients belonging to Neurosurgery (49), Neuromedicine (48), Cardiac medicine (30) wards and Blood donors (30) as healthy controls were investigated for the prevalence of Toxoplasmosis by means of detecting specific IgM antibody against Toxoplasma gondii (T. gondii) employing Enzyme Immuno Assay (EIA). The detection rate of specific IgM antibody against T.gondii was found to be 32.7% (16/49) among Neurosurgery patients, 20.8% (10/48) among Neuromedical patients and 20% (6/30) among Cardiac medical patients. None of the voluntary blood donors tested was found to have T. gondii IgM antibody. Maximum prevalence rate was found among female patients undergoing Neurosurgery (42.3%) followed by Neuromedical patients (40%). There is an increasing rate of prevalence of Toxoplasmosis from the lower age group upto thirty years and a declining prevalence rate among the higher age groups. The present study revealed high prevalence rate of Toxoplasmosis in Neurosurgery patients (32.7%) and in particular among female (35.2%) than male (17.8%) patients.  相似文献   

4.
An electroejaculation technique was applied to the Hokkaido brown bear (Ursus arctos yesoensis) for semen collection and characterization of their seminal traits. Ten captive sexually mature bears were anesthetized and subjected to 21 electroejaculation trials during their mating season in 1995 and 1996. Spermic electroejaculates were recovered from 6 of the 10 bears (14 of 21 trials). The semen was characterized by serous fluid of semitransparent white color and a neutral pH. The mean values of ejaculate volume, sperm concentration, percentage of sperm motility, percentage of live spermatozoa, and percentage of pleiomorphic forms were 2.7 ml, 471.6 x 10(6) cells/ml, 80.2%, 89.7% and 21.8%, respectively. Although there was considerable variation among the seminal traits of the individual bears, the electroejaculation technique was effective in obtaining ejaculates from captive bears.  相似文献   

5.
One hundred and thirty-four (26%) of 511 sera from 11 wild animal species in eight prefectures in Japan had antibody titers to Coxiella burnetii by the enzyme-linked immunosorbent assay. High prevalences were observed in Japanese black bears (Ursus thibetanus) (78%), Hokkaido deer (Cervus nippon yesoensis) (69%), Japanese hares (Lepus brachyurus) (63%), Japanese deer (Cervus nippon centralis) (56%), and to some extent in Japanese monkeys (Macaca fuscata) (28%). A low prevalence (13%) was observed in nutrias (Myocastor coypus). Japanese serows (Capricornis crispus), wild rats (Muroides sp.), raccoon dogs (Nyctereutes procyonoides viverrinus), wild pigs (Sus scrofa leucomystax), and masked palm civets (Paguma larvata) had no detectable antibodies to C. burnetii. Thus, six of 11 wild animal species in Japan were exposed to C. burnetii. Based on the high prevalences in some species, they may be a potential source of infection to both domestic animal and human populations.  相似文献   

6.
Bear bones and Paleolithic stone artefacts often co-occur in Pleistocene cave deposits of Eurasia, raising the question of how these associations come about and the need for effective methods with which to obtain a clear answer. Building upon knowledge of modern bears, I present a method for testing two competing hypotheses about the causes of bear mortality in hibernation contexts. The first hypothesis proposes that age-dependent deaths resulted from non-violent causes (principally starvation), implying that bears' presence in a cave was not linked in time to human activities there. The second hypothesis proposes that random bear deaths in caves resulted from hunting by humans or other large predators, implying a temporal link between them; the expectation of a nonselective age pattern in this circumstance arises from the fact that the individual characters of hibernating bears are hidden from predators. Three elements of the method and its development are presented: (1) a brief review of the biological bases of hibernation-related mortality in modern Ursus, its paleontological consequences, and test expectations drawn therefrom; (2) a detailed, illustrated technique for age-scoring isolated bear cheek teeth based on tooth eruption-wear sequences, developed primarily for cave and brown bears; and, (3) a simple, accurate way to evaluate real cases in terms of contrasting mortality models. The final step is demonstrated by application to a Middle Pleistocene cave bear assemblage (Ursus deningeri) from Yarimburgaz Cave in Turkey, a large collection found in general stratigraphic association with Paleolithic artefacts. The advantages of the method include its ability to (a) handle small samples, (b) use isolated tooth specimens, and (c) evaluate cases simultaneously in terms of idealized age structure models and the variation that normally is associated with each under natural conditions. While the more obvious benefit of bear mortality analysis may be to research on ancient bear demography, the principles and procedures offered here are equally pertinent to archaeological studies of carnivore-mediated formation processes in cave sites. As is generally true in taphonomic research, however, bear mortality patterns are most effective when used in combination with independent lines of evidence to address questions about assemblage formation.  相似文献   

7.
Sera from camels from Egypt were examined by the direct agglutination tests incorporating mercaptoethanol for antibodies to Neospora caninum and Toxoplasma gondii. Antibodies to N. caninum were found in 6 of 161 camels in titers of 1:40 (2 camels) and 1:80, 1:160, 1:640, and 1:1280 in 1 camel each, using N. caninum formalin preserved whole tachyzoites as antigen. Antibodies to T. gondii were found in 17.4% of 166 camels in titers of 1:25 (3 camels), 1:50 (18 camels). and > 1:500 (8 camels) using T. gondii tachyzoites. All 6 camels with N. caninum antibodies had no T. gondii antibodies in 1:4 dilution of serum, indicating specificity of the reaction. This is the first report of N. caninum prevalence in Egypt.  相似文献   

8.
Twelve of 3803 consecutive marrow allograft patients treated at this center over the past 20 years have had a post-transplant tissue diagnosis of toxoplasmosis: 10 at autopsy and 2 by brain biopsy. This infection was identified in none of 509 autologous marrow recipients. Occurrence of toxoplasmosis was 0.31 cases per 100 allogeneic transplants and 1.0 per 100 autopsies. An estimated 15% of allogeneic transplant recipients were seropositive for Toxoplasma gondii and 2% of seropositive patients developed toxoplasmosis. Pre-transplant serology was positive by both dye and agglutination tests in 11 infected patients tested. Sequential IgG, IgM, IgA, IgE antibody titers to T. gondii and the differential agglutination ratio were not helpful in diagnosing toxoplasmosis. Median day of clinical presentation was day 59 post-transplant (35-97 days) and of diagnosis, day 62 after transplant (37-143 days). Eleven patients had graft-versus-host disease (GVHD) of grades II-IV. All 12 patients died. Infection was diagnosed prior to death in only 16% of patients and contributed to death in at least 40%. Histopathology revealed tachyzoites of T. gondii most prevalent in brain (100%), heart (67%) and lungs (33%), and toxoplasma cysts alone in heart (33%) and lungs (22%). Toxoplasma infection was diagnosed in two patients receiving trimethoprim-sulfamethoxazole for Pneumocystis carinii pneumonia prophylaxis suggesting this was insufficient prophylaxis for toxoplasmosis. Toxoplasmosis appeared to occur by reactivation within the first 6 months after marrow transplant. Infection developed in patients who were seropositive for T. gondii pre-transplant, had received allogeneic marrow and had severe GVHD.  相似文献   

9.
Serum samples from 1,264 feral pigs from Ossabaw Island, Georgia were initially screened for antibodies to Toxoplasma gondii by the modified agglutination test (MAT) using whole-formalinized tachyzoites and mercaptoethanol. Seropositive samples were also tested by the Sabin-Feldman dye test, the latex agglutination test (LAT), and the indirect hemagglutination test (IHAT). Ossabaw Island is a remote, barrier island located southeast of Savannah, Georgia. Antibodies to T. gondii were found in 11 (0.9%) of 1,264 pigs. The antibody titers were 1:20 (1 pig), 1:80 (2 pigs), 1:160 (2 pigs), 1:320 (4 pigs), and 1:640 (2 pigs) by the MAT, and 1:8 (2 pigs), 1:16 (3 pigs), 1:32 (1 pig), 1:64 (2 pigs), 1:128 (1 pig), and > or = 1:256 (2 pigs) by the Sabin-Feldman dye test. By the LAT, 5 pigs had a titer of > or = 1:64 and by the IHAT all 11 pigs had a titer of < 1:64. Antibodies (MAT titer, > or = 1:25) were found in 31 (18.2%) of 170 feral pigs from mainland Georgia. This seroprevalence on the mainland was significantly higher (P < 0.0001) as compared on Ossabaw Island. The markedly low prevalence of T. gondii on Ossabaw Island was attributed to the virtual absence of cats on the Island; only 1 domestic cat was known to be present.  相似文献   

10.
Hepatitis C virus antibody (anti-HCV) was studied in 267 patients undergoing maintenance hemodialysis using an anti-HCV enzyme-linked immunosorbent assay. Furthermore, both hepatitis B virus core antibody (anti-HBc) and human T cell leukemia virus type 1 antibody (anti-HTLV-1) were determined in these patients to compare their prevalence rates. Seventy one patients (27%) had positive anti-HCV, 134 patients (50%) positive anti-HBc and 40 patients (15%) positive anti-HTVL-1. Among the 183 patients who had received blood transfusion, the prevalence of these antibodies was 34% for anti-HCV, 56% for anti-HBc and 17% for anti-HTLV-1, respectively. A significance between those with and without blood transfusion was recognized for anti-HCV (p < 0.001) and anti-HBc (p < 0.01). Of 56 patients who had received hemodialysis for over 15 years, the positive antibody was found in 63% for anti-HCV (p < 0.001), 73% for anti-HBc (p < 0.001) and 25% for anti-HTLV-1 (p < 0.05), which was significantly higher than that of patients receiving a less than 15 years hemodialysis. The prevalence rates of anti-HCV and anti-HTLV-1 did not increase with age, while that of anti-HBc increased. These findings suggest that blood transfusions during hemodialysis play a very important role in the infection of hepatitis C virus.  相似文献   

11.
Serum samples from 107 cervids were examined for Toxoplasma gondii antibodies using indirect hemagglutination (IHA), indirect immunofluorescence (IFA), enzyme linked immunosorbent assay (ELISA) and Dot-ELISA. Samples were obtained from 66 marsh deer (Blastocerus dichotomus) in the State of S?o Paulo (Brazil) and from 41 pampas deer (Ozotocerus bezoarticus) in the State of Goiás (Brazil). Antibodies to T. gondii were found in 23 (22%) of the deer, with 18 and 5 positive samples, respectively, for B. dichotomus and O. bezoarticus. The highest prevalence of T. gondii antibodies were young adults (32%), following by adults (27%) and fawns (13%). Only one serum sample (8%) from a newborn fawn was positive in the serological tests. The convenience of the Dot-ELISA test is obvious when compared with other serological tests for both laboratory or field surveys, mainly due to its features of practicability and reagent stability.  相似文献   

12.
The Toxoplasma gondii rhoptry protein Rop2 was expressed in Escherichia coli as a fusion protein containing 44 kDa of the 55-kDa mature Rop2, supplied with six histidyl residues at the N-terminal end (Rop2196-561). Humoral response during Toxoplasma infection of humans was analyzed by immunoglobulin G (IgG), IgA, and IgM enzyme-linked immunosorbent assay with Rop2196-561 as the antigen substrate. The analyzed sera were divided according to T. gondii-specific serological tests (IgG, IgA, or IgM indirect immunofluorescence and IgA or IgM immunosorbent agglutination assay) as group A (IgG+ IgA- IgM-; n = 35), group B (IgG+ IgA+ IgM+; n = 21), group C (IgG+ IgA+ IgM-; n = 5), and group D (IgG+ IgA- IgM+; n = 16). Twenty-six T. gondii-seronegative sera from individuals with other infections were also included (group E). Anti-Rop2 IgG antibodies were detected in 82.8% of group A sera and in 97.6% of the sera with acute-phase marker immunoglobulins (groups B, C, and D). The percentage of IgA antibody reactivity against Rop2196-561 was 17.1% in group A, 50% in group D, and 80.8% in groups B and C. The percentage of IgM antibody reactivity was 0% in groups A and C and 62% in groups B and D. Sera from group E failed to show IgA, IgM, or IgG antibody reactivity. Since T. gondii Rop2 elicits a strong humoral response from an early stage of infection, it is suggested that recombinant Rop2196-561 would be suitable for use in diagnostic systems, in combination with other T. gondii antigens, to detect specific IgG, IgA, and IgM antibodies.  相似文献   

13.
To determine the extent of phylogeographic structuring in North American black bear (Ursus americanus) populations, we examined mitochondrial DNA sequences (n = 118) and restriction fragment length polymorphism profiles (n = 258) in individuals from 16 localities. Among the bears examined, 19 lineages falling into two highly divergent clades were identified. The clades differ at 5.0% of nucleotide positions, a distance consistent with an origin 1.8 MYA, and have different but overlapping geographical distributions. Areas of clade cooccurrence show that eastern and western populations are currently mixing, but regional differences in lineage distribution suggest that mixing has begun only recently. The long-term population history of black bears appears to be characterized predominantly by long-term regional isolation followed by recent contact and hybridization. Congruence between the pattern of diversity observed in black bears and patterns of forest refuge formation during the Pleistocene supports earlier speculation that Pleistocene forest fragmentations underlie a common pattern in the phylogeography of North American forest taxa.  相似文献   

14.
Adipose tissue samples from polar bears (Ursus maritimus) were obtained by necropsy or biopsy between the spring of 1989 to the spring of 1993 from Wrangel Island in Russia, most of the range of the bear in North America, eastern Greenland, and Svalbard. Samples were divided into 16 regions corresponding as much as possible to known stocks or management zones. Concentrations of dieldrin (DIEL), 4,4'-DDE (DDE), sum of 16 polychlorinated biphenyl congeners (sigma PCB), and sum of 11 chlordane-related compounds and metabolites (sigma CHL) were determined. In order to minimize the effect of age, only data for adults (320 bears age 5 years and older) was used to compare concentrations among regions. Concentrations of sigma PCB were 46% higher in adult males than females, and there was no significant trend with age. Concentrations of sigma CHL were 30% lower in adult males than females. Concentrations of sigma PCB, sigma CHL, and DDE in individual adult female bears were standardized to adult males using factors derived from the least-square means of each sex category, and geometric means of the standardized concentrations on a lipid weight basis were compared among regions. Median geometric mean standardized concentrations (lipid weight basis) and ranges among regions were as follows: sigma PCB, 5,942 (2,763-24,316) micrograms/kg; sigma CHL, 1,952 (727-4,632) micrograms/kg; DDE, 219 (52-560) micrograms/kg; DIEL, 157 (31-335) micrograms/kg. Geometric mean sigma PCB concentrations in bears from Svalbard, East Greenland, and the Arctic Ocean near Prince Patrick Island in Canada were similar (20,256-24,316 micrograms/kg) and significantly higher than most other areas. Atmospheric, oceanic, and ice transport, as well as ecological factors may contribute to these high concentrations of sigma PCB. sigma CHL was more uniformly distributed among regions than the other CHCs. Highest sigma CHL concentrations were found in southeastern Hudson Bay, which also had the highest DDE and DIEL concentrations. In general, concentrations of sigma CHL, DDE, and DIEL were higher in eastern than western regions, suggesting an influence of North American sources. Average sigma PCB concentrations in bears from the Canadian Arctic were similar to those in 1982-84, while average sigma CHL and DDE concentrations were 35-44% lower and DIEL was 90% lower. However, the significance of these temporal trends during the 1980s is not conclusive because of the problems of comparability of data.  相似文献   

15.
Sera from randomly selected 49 professional blood donors, 617 pregnant women, 14 butchers, 528 slaughtered goats and 24 domestic cats in the district of Mymensingh were tested for the presence of T. gondii antibodies using a Latex agglutination test (LAT). Overall 12.4% blood donors, 11.18% pregnant women, 50.00% butchers, 12.88% slaughtered goats and 33.33% cats had diagnostically significant antibody titers (> or = 1:64) to T. gondii. Epidemiological studies on T. gondii infection with LAT were conducted in 25 family members with sero-positive cats and 9 family members with 2 sero-positive women without cats in the family. Significantly (p < 0.01) higher sero-positivity rate was recorded in the family members (24.00%) with positive cats in comparison to family members (11.11%) without cats. The epidemiologic study indicates that infected cats and goat meat might be significant sources of T. gondii infection for humans in Bangladesh.  相似文献   

16.
Seroprevalence of Bartonella henselae and Toxoplasma gondii was investigated among 471 pet cats obtained from seven private animal hospitals in Kanagawa and Saitama Prefectures during the period from May 1994 to June 1995. 'Furthermore, 67 randomly selected from the 471 serum samples were examined for the feline immunodeficiency virus (FIV) antibody and feline leukemia virus (FeLV) antigen. The antibody to B. henselae was examined by an indirect immunofluorescent antibody test. T. gondii, FIV and FeLV infections in cats were detected with respective commercial kits. Of the cat serum samples tested, 43 (9.1%) were found to be seropositive for B. henselae and 41 (8.7%) for T. gondii. The B. henselae-positive rate (12.9%) of male cats was significantly higher than that (5.2%) of female cats. On the other hand, T. gondii-positive rate was 9.1% in male and 8.7% in female cats and there was no significant difference in the positivity between sexes. The positive rate in each hospital varied from 0 to 19.5% for B. henselae and 4.9 to 18.8% for T. gondii. The ages of B. henselae- and T. gondii-positive cats were distributed from < 1-year-old to 14-year-old and the seropositivity increased with age of cats. Of the 67 cat serum samples, 16 and 6 cases were positive for FIV and FeLV, respectively. There was no relationship between these viral and B. henselae infections in cats.  相似文献   

17.
In a previous report, we showed that addition of colchicine to cultures of glial cells infected with Toxoplasma gondii decreased the number of parasites by up to 80%. To provide support for potential therapeutic use of colchicine in toxoplasmosis, a murine model of T. gondii infection was used. Mice infected with pure RH T. gondii tachyzoites (from 2,233 to 25,000 parasites) were treated daily with either pyrimethamine (80 or 51 mg/kg), colchicine (10 mg/kg), pyrimethamine-colchicine, or vehicle (controls). Survival rates were lower in animals treated with colchicine (from 40% to 27%) and pyrimethamine-colchicine (from 73% to 41%) than in animals treated with pyrimethamine alone (from 100% to 73%). There was no extension of mean survival time in animals treated with colchicine compared to controls. These results demonstrate that colchicine does not improve the course of acute toxoplasmosis in mice, and it is detrimental rather than beneficial at the regimen tested.  相似文献   

18.
We critically review and summarize information on the prevalence of Toxoplasma gondii infections in rats, mainly Rattus norvegicus, and their possible role as a source of infection for larger carnivores and omnivores. We also review information on immunology and natural resistance, contributing to the model value of rats in the analysis of human infection. Rats can be successfully infected with oocysts (sporozoites), tissue cysts (bradyzoites), and tachyzoites. Even adult rats, that are resistant to clinical toxoplasmosis, can be infected orally with a few oocysts or tissue cysts. Infections with tachyzoites of the RH strain are highly variable. Congenital transmission of T. gondii occurs at a high rate when rats are infected during pregnancy. Congenitally infected rats can harbor viable T. gondii in the absence of detectable antibodies to T. gondii and rats with low antibody titers may harbor few or no organisms. The isolation of viable T. gondii by bioassay is the only reliable means to determine persistence of chronic T. gondii infection in feral rats. No evidence was found for maintenance of T. gondii in rats by vertical transmission in the absence of cats.  相似文献   

19.
The prevalence of hepatitis B virus (HBV) infection in the South African urban obstetric population, which consists of white, black, coloured and Asian patients from different socio-economic, cultural and geographical backgrounds, is unknown. Routine screening performed in 3,469 urban pregnant women revealed that 42 patients were HBV surface antigen-positive (a prevalence of 1.21%). Only 2 patients (4.6%) were hepatitis B e antigen (HBeAg)-positive (0.06% of the entire cohort), whereas the remaining 40 were identified as hepatitis B e antibody-positive. Despite a significant increase in the numbers of black patients, there has not been an accompanying increase in the number of HBV carriers. Replicative infection was equally distributed among white and black pregnant women. Because the low prevalence of HBeAg results in lack of perinatal transmission and the prevention of a single case of neonatal hepatitis B infection is costly, we conclude that in South African urban hospitals, routine screening for hepatitis B is not cost-effective.  相似文献   

20.
BACKGROUND: Chlamydia pneumoniae has been identified in coronary atheroma, but concomitant serum antibody titers have been inconsistently positive and unavailable before the detection of early or advanced atherosclerotic lesions. METHODS AND RESULTS: This retrospective investigation was performed on premortem serum specimens and autopsy tissue from 60 indigenous Alaska Natives at low risk for coronary heart disease, selected by the potential availability of their stored specimens. Serum specimens were drawn a mean of 8.8 years (range, 0.7 to 26.2 years) before death, which occurred at a mean age of 34.1 years (range, 15 to 57 years), primarily from noncardiovascular causes (97%). Coronary artery tissues were independently examined histologically and, for C pneumoniae organism and DNA, by immunocytochemistry (ICC) and polymerase chain reaction (PCR) with species-specific monoclonal antibody and primers. Microimmunofluorescence detected species-specific IgG, IgA, and IgM antibody in stored serum. C pneumoniae, frequently within macrophage foam cells, was identified in coronary fibrolipid atheroma (raised lesions, Stary types II through V) in 15 subjects (25%) and early flat lesions in 7 (11%) either by PCR (14, 23%) or ICC (20, 33%). The OR for C pneumoniae in raised atheroma after a level of IgG antibody > or =1:256 >8 years earlier was 6.1 (95% CI, 1.1 to 36.6) and for all coronary tissues after adjustment for multiple potential confounding variables, including tobacco exposure, was 9.4 (95% CI, 2.6 to 33.8). CONCLUSIONS: Serological evidence for C pneumoniae infection frequently precedes both the earliest and more advanced lesions of coronary atherosclerosis that harbor this intracellular pathogen, suggesting a chronic infection and developmental role in coronary heart disease.  相似文献   

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