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1.
Two eland Anaplasma isolates, AnapE1, from Kenya, and AnapE2, from South Africa were characterised. Their characterization was based on their pathogenicity to intact and splenectomized cattle and sheep and also their DNA profiles. Their DNA profiles were analysed and compared to Anaplasma marginale, A. ovis and A. centrale after endonuclease restrictions and probing with Anaplasma DNA probes, AC5-12 and AC-1. The results of the pathogenicity trials showed AnapE1 to be similar to A. ovis and AnapE2 an isolate of A. marginale. On DNA profiles, AnapE1 was close to A. ovis, with differences that occur even in same Anaplasma species isolates from different locations. On the other hand, AnapE2, resembled one of the A. marginale isolates known to occur in South Africa. The DNA profiles correlated well with the pathogenicity results. It is concluded that elands are carriers of both A. marginale and A. ovis parasites and are therefore important reservoirs that need attention in epidemiology of anaplasmosis.  相似文献   

2.
Semen samples taken from 21 rams with pronounced pathologic changes were studied in a complex way to establish the etiology contributing to the deterioration of the semen quality. The complement-fixation test was applied with blood serum and semen plasma along with the microscopic study of the semen for the excretion of Brucella ovis organisms and a clinical examination. The following results were obtained: 1. The semen plasma of 90.5 per cent of the rams was positive for Brucella ovis. A total of 80.9 per cent were CFT-positive, and the same per cent of the animals were positive for the excretion of Brucella ovis organisms with the semen. The three diagnostic methods give equally positive results in 84.2 per cent of the cases. 2. The clinical examination revealed gross lesions in the genital apparatus in 33.3 per cent of the investigated animals, which coincided with the results obtained through the above-mentioned three methods in 85.9 per cent of the cases. 3. The simultaneous application of the blood serum and semen CFT, the bacteriologic investigation of the semen, and the clinical examination makes it possible to establish the etiology responsible for the defective spermogram of the rams studied.  相似文献   

3.
A trial was designed to test the efficacy of vaccination of lambs against field challenge with T. ovis eggs using 3 different levels of pasture contamination. Three concentric paddocks (1.62 hectares each) were used and the inner paddock was heavily contaminated with T. ovis eggs by tethering 2 dogs, experimentally infected with T. ovis, at 5 different points in the paddock over a period of 1 month. Four groups of lambs were used. Sixty lambs, from a property known to be free of T. ovis for 2 years previously, were divided into 2 groups of 30 each; one group was vaccinated with T. ovis culture antigen (vaccinated group=V) while the other was vaccinated with culture medium without antigen (sham-vaccinated group=SV). Thirty mature sheep were obtained from a property with a recent record of T. ovis infection (previous natural exposure to infection group=PNE) and 15 lambs were artificially reared from birth under cestode-egg-free conditions (artificially reared groups= AR). Ten animals from groups V, SV, and PNE, and 5 AR lambs were grazed on each of the 3 concentric paddocks for 6 weeks, and then all animals were slaughtered and their total muscle mass (including heart, diaphragm, tongue and masseters) examined, by slicing, for T. ovis cysticerci. The mean total numbers of T. ovis cysticerci recovered were as follows: Inner paddock, PNE 45.5, AR 47.6, SV 107.8, V 6.5; Middle paddock, PNE 5.2, AR 9.0, SV 8.2, V 0.3; Outer paddock, PNE 2.9, AR 2.8, SV 2.3, V 0.2. There were 4 major conclusions from this study. Firstly, vaccination was more effective than previous natural exposure to infection in preventing establishment of new cysticerci. Secondly, although vaccination effectively reduced the numbers of cysticerci, those that became established were mostly viable at the time of slaughter. In contrast, PNE sheep had greater numbers of cysticerci but the majority were degenerating. Vaccination, therefore, did not seem to stimulate a complete immunological response. Thirdly, the presence of T. hydatigena in lambs did not prevent subsequent infection with T. ovis. Fourthly, T. ovis eggs were dispersed from the inner paddock to the outer paddock.  相似文献   

4.
Investigations into the incidence of Salmonella abortus ovis (S. abortus ovis) infections should not be neglected in diagnosis of ovine abortion cases. For detection of this pathogen agent, direct cultivation, as well as pre-enrichment combined with enrichment procedures in tetrathionate or Rappaport-Vassiliadis medium, should be performed with respect to the features of S. abortus ovis. The detection limit of S. abortus ovis using pre-enrichment and enrichment media could be determined using 6.5 x 10(3)-6.5 x 10(4) bacteria. For subsequent cultivation of S. abortus ovis Gassner, XLD or Rambach agar are suitable. In infected sheep showing no excretion of S. abortus ovis, the pathogen can be detected by serological studies using microagglutination or the ELISA test. The ELISA test proved to be more sensitive than the microagglutination test, detecting antibodies against S. abortus ovis in 17% of the 814 sheep tested. The microagglutination test revealed positive results in only 2% of the sheep tested.  相似文献   

5.
The prevalence of actinomyces-like organisms in cervicovaginal smears of 2,327 Chinese women, including 1,279 intrauterine devices (IUD) wearers and 1,048 non wearers, was investigated. Cervical smears were stained by the Papanicolaou method for the microscopic examination of actinomyces-like organisms. The relationship between actinomyces-like organisms infection and occupations, age, duration of IUD wearing and clinical symptoms were analysis. The result showed that the overall detection rate of actinomyces-like organisms in 2,327 women was 0.69%. The detection rates in IUD wearers and non-wearers were 1.1% and 0.2%, respectively, which were significantly different (P < 0.01). The rate of actinomyces-like organisms infection was significantly higher in women wearing IUD for more than seven years. Whereas the occupation or age of women did not affect the detection rate significantly.  相似文献   

6.
7.
A filter immunobinding (FIB) method was developed for the detection and identification of mycoplasmas. Type strains of a total of 18 avian and bovine mycoplasma species propagated in broth media were diluted and immobilized on a nitrocellulose membrane as antigens for investigating the specificity with rabbit hyperimmune sera. Non-specific FIB reactions were easily eliminated by the procedure of absorbing rabbit hyperimmune sera in the broth. Absorbed rabbit hyperimmune sera exhibited clear species-specificity with mycoplasma antigens by the FIB. These specific reactions always agreed with the results of identification by tests of biochemical properties and growth inhibition for the isolates of M. bovirhinis, M. bovis, M. columbinum, M. columborale, M. gallisepticum and M. synoviae. Some bovine mycoplasma species, which were impossible to identify by growth inhibition test, because of their strong production of film and spots on the agar, specifically reacted with absorbed rabbit hyperimmune sera against M. bovis in the FIB. The detection limit of mycoplasmas by this method was about 10(4)-10(5) colony-forming units/ml, which is lower than that of colony determination on agar. The FIB seems to be a useful technique for rapid detection and simultaneous identification of mycoplasmas.  相似文献   

8.
Cytokine profiles were determined following intranasal infection of C57BL/6J mice with murine gammaherpesvirus 68 (MHV-68). Spleen, mediastinal, and cervical lymph node cells from infected mice produced high levels of interleukin 6 (IL-6) and gamma interferon (IFN-gamma) and lower levels of IL-2 and IL-10 following in vitro restimulation. Little or no IL-4 or IL-5 was detected. Cytokine production was generally maximal at 10 days after infection, correlating with viral clearance from the lung, although significant levels were seen as early as 3 days after administration of the virus. In vitro infection of naive splenocytes induced B-cell- dependent secretion of IL-6 and IL-10, whereas IFN-gamma and IL-2 were produced only by cells that had been primed in vivo. Depletion of B lymphocytes from primed splenocyte populations did not, however, abrogate IL-6 and IL-10 production. Highly purified immune T cells made IL-6, IL-10. and IFN-gamma following in vitro restimulation with MHV-68. Thus, IL-6 and IL-10 are components of both the acquired and the innate host response. These cytokines have potential roles in the establishment and maintenance of persistent infection.  相似文献   

9.
OBJECTIVE: To define chronic hepatitis C virus (HCV) infection among patients with persistently normal aminotransferase levels (PNAL). DESIGN: Retrospective chart review of all patients encountered during 1-yr with positive hepatitis C antibody (anti-C100-3 ELISA), no alternative cause for their liver disease and PNAL for 6 or more consecutive months prebiopsy. Blinded review of liver histology. SETTING: Outpatient hepatology clinics of two academic centers. PATIENTS: Fifty patients with PNAL among 303 with hepatitis C. MEASUREMENTS: Epidemiologic profiles, reasons for seroscreening and confirmatory analyses were tabulated. Histology was reviewed and grading of inflammatory activity and stage of fibrosis was determined by protocol. RESULTS: Among 50 patients with PNAL, 35 (70%) were female, 34 (68%) had parenterally acquired HCV, 44 (88%) abstained (> 2 yr) from ethanol, all were HIV-negative and none pharmacologically immunosuppressed. HCV infection was uniformly confirmed by RIBA II or HCV-RNA assay. The mean level of HCV-RNA by quantitative PCR was 3.79 x 10(5) copies/ml (range, 500 to 1.8 x 10(6) copies/ ml) and by B-DNA, 53 x 10(5) copies/ml (range, 3.5-230 x 10(5) copies/ml). Traditional histoevaluation yielded chronic hepatitis ("active", n = 15; "persistent", n = 25), cirrhosis (n = 7), and normal histology (n = 3). Blinded protocol review of histology (inflammatory grade/fibrotic stage) revealed 0/0 (n = 4), 1/0 (n = 6), 2/0 (n = 17), 2/1 (n = 3), 2/4 (n = 1), 3/0 (n = 2), 3/1 (n = 6), 3/2 (n = 2), and 3/3 (n = 9). CONCLUSIONS: In chronic HCV infection, active inflammation, fibrosis, and variable circulating HCV-RNA levels may coexist with PNAL, particularly among female nondrinkers. Asymptomatic carriers with normal histology comprise 6 to 8% of chronic hepatitis C with PNAL. Management guidelines for this group of patients need to be developed.  相似文献   

10.
A GLC method, based on flame-ionization detection, was developed for the assay of methotrimeprazine and its sulfoxide in plasma. For a 6-ml aliquot, the sensitivity was 2-3 ng/ml for the unchanged drug and 4-5 ng/ml for the sulfoxide. The coefficient of variation, calculated from duplicate analyses of plasma samples, was 8-15% for concentrations between 10 and 100 ng/ml. Patients treated with orally administered methotrimeprazine had higher plasma levels of the sulfoxide than of unmetabolized drug. The method also was applied to the analysis of promazine and chlorpromazine in patient plasma.  相似文献   

11.
Protective immunity against the ehrlichial pathogen Anaplasma marginale has been hypothesized to require induction of immunoglobulin G2 (IgG2) antibody against outer membrane protein epitopes and coordinated activation of macrophages for phagocytosis and killing. In the present study, cell-mediated immune responses, including induction of IgG isotype switching, were characterized in calves immunized with purified outer membranes of the Florida strain of A. marginale. Importantly, these calves were subsequently shown to be protected upon experimental challenge with the Florida strain, and calves which developed the highest IgG2 titers were completely protected against infection. Peripheral blood mononuclear cells (PBMC) obtained after immunization proliferated strongly in response to both whole A. marginale homogenates and purified outer membranes, and this responsiveness persisted until the time of challenge. Responding cells were shown to be CD4(+) T cells, and CD4(+) T-cell lines cultured for 2 to 4 weeks also proliferated specifically in response to A. marginale and produced high titers of gamma interferon. The helper T-cell response included recognition of conserved epitopes, as PBMC proliferation was stimulated by the homologous Florida strain, four genetically distinct A. marginale strains, and Anaplasma ovis. The outer membrane proteins stimulating the PBMC responses in protected calves included major surface proteins (MSPs) MSP-1, MSP-2, and MSP-3, which were previously shown to induce partial protection against infection. These studies demonstrate, for the first time, potent helper T-cell responses in cattle protectively immunized with outer membranes against A. marginale challenge and identify three MSPs that are recognized by immune T cells. These experiments provide the basis for subsequent identification of the helper T-cell epitopes on MSP-1, MSP-2, and MSP-3 that are needed to evoke anamnestic antibody and effector T-cell responses elicited by protein or nucleic acid immunization.  相似文献   

12.
A GLC method, based on flame-ionization detection, was developed for the assay of methotrimeprazine and its sulfoxide in plasma. For a 6-ml aliquot, the sensitivity was 2-3 ng/ml for the unchanged drug and 4-5 ng/ml for the sulfoxide. The coefficient of variation, calculated from duplicate analyses of plasma samples, was 8-15% for concentrations between 10 and 100 ng/ml. Patients treated with orally administered methotrimeprazine had higher plasma levels of the sulfoxide than of unmetabolized drug. The method also was applied to the analysis of promazine and chlorpromazine in patient plasma.  相似文献   

13.
The analysis of morphine in biological fluids is of vital interest in monitoring opiate abuse and in drug abuse research. Although methods for analysis of morphine and its metabolites are well established, studies are still being carried out to improve sample preparation procedures as well as detection levels of morphine in biological samples. In this study, morphine-specific immunosorbents were developed to concentrate morphine prior to HPLC analysis. Urine (0.1 ml) was diluted 10-fold with phosphate-buffered saline, pH 7.4 (PBS), loaded onto a solid-phase immunoextraction column and washed with 15 ml PBS followed by elution with 2 ml of elution buffer (40% ethanol in PBS, pH 4). The eluted fraction was analysed for morphine by HPLC-electrochemical detection using a cyanopropyl (CN) analytical column with 25% acetonitrile in phosphate buffer-sodium lauryl sulphate, pH 2.4 as the mobile phase. Duration of the extraction procedure was approximately 40 min. Calibration graphs were linear from 100 ng ml-1 to 500 ng ml-1 in urine. The inter-assay R.S.D. was < 10% and the recovery of morphine from urine was > 98%. Immunocolumns demonstrated remarkably high specificity towards morphine showing minimal binding with other opiate metabolites such as codeine, normorphine, norcodeine, morphine-3-glucuronide, morphine-6-glucuronide.  相似文献   

14.
Cytokines may have clinical utility as therapeutic agents for human immunodeficiency virus type 1 (HIV-1) infection and as an adjuvant for vaccines. The effect of interleukin-12 (IL-12) and IL-15 on in vitro HIV-1 replication was investigated. IL-12 and IL-15 at doses up to 10 ng/ml had little effect on basal HIV-1 p24 antigen production by chronically HIV-infected T (ACH-2) and monocytic (U1) cell lines. For ACH-2 cells stimulated with phorbol 12-myristate 13-acetate (PMA; 50 ng/ml), IL-12 and IL-15 significantly increased p24 antigen production by 20 and 30%, respectively (n = 6). In contrast, IL-12 and IL-15 (10 ng/ml) treatment of PMA-stimulated U1 cells decreased p24 antigen production by 16 and 15%, respectively (n = 6). We next studied the effect of IL-12 and IL-15 on HIV-infected peripheral blood mononuclear cells (PBMCs). In 10 HIV-seropositive patients' PBMCs cocultured with mitogen-activated HIV-seronegative donor cells, two patterns of p24 antigen production were observed in response to IL-2: low (p24 antigen production < 10(3) pg/ml; n = 8) and high (p24 antigen production > 10(3) pg/ml; n = 2) response. For the low-response pattern, IL-12 and IL-15 increased viral replication by 97-fold and 100-fold, respectively (P = 0.05 and 0.004, respectively). For the high-response pattern, both IL-12 and IL-15 suppressed HIV replication. The effect of IL-2, IL-12, and IL-15 on acute in vitro infection by HIV-1JRCSF was also examined. IL-12 did not increase p24 antigen production above basal levels while IL-2 and IL-15 significantly enhanced p24 antigen production (by approximately 2-fold). In conclusion, IL-12 and IL-15 may have differential effects on latent and acute HIV infection, and their ability to enhance HIV production may depend on cell activation. Thus, the use of these cytokines may be dictated by the clinical state of the patient.  相似文献   

15.
The concentrations of eight metals were determined by a nondestructive neutron activation technique for eleven species of fish and shellfish. The marine organisms were collected from ocean dump sites off New York City, off New Haven, Connecticut, and off Delaware Bay. Antimony was not detected in most of the organisms examined in thid study; the detection limit was about 0.02 to 0.05 ppm. Antimony levels ranged from 0.01 to 0.129 ppm in fish that had detectable levels. Cobalt levels were low in all samples with most levels in the range of 0.1 to 0.3 ppm. Chromium concentrations at 0.3 to 1.0 ppm were only roughly quantitated by the procedure employed. Most marine organisms examined had chromium levels at or below these values. Nickel was not detected in any of the organisms examined; the detection limit was in the 3 to 6 ppm range. Rubidium concentrations were 0.6 to 1.5 ppm for most organisms; only rough quantitative measurement was possible at these levels. Selenium levels ranged from about 0.3 to 3.8 ppm in all samples. Silver concentrations were below 0.3 ppm in most organisms. Silver concentrations as high as 10 to 30 ppm, however, were found in the digestive gland of rock crab. Zinc levels in windowpane flounder liver were about 6 to 9 times greater than the 4 to 10 ppm levels found in muscle. Zinc concentrations in rock crab muscle, on the other hand, were only slightly higher than the 15 to 32 ppm concentration found in the digestive gland. Fish other than windowpane flounder had zinc levels that ranged from 4 to 9 ppm in the muscle and 14 to 42 ppm in the liver. Shellfish other than rock crab had zinc levels of 15 to 30 ppm in muscle and 17 to 40 ppm in the digestive gland.  相似文献   

16.
17.
The aim of this study was to investigate the presence of hepatitis B virus occult infection in asymptomatic subjects with persistent anti-HBc reactivity but no other hepatitis B virus serological markers, including HBsAg, anti-HBs, IgM anti-HBc and HBV-DNA. For this purpose we used both polymerase chain reaction assays in sera and immunohistochemistry for HBsAg and HBcAg in liver biopsy specimens. Twenty-four cases were studied: 15 were drug abusers or homosexuals (eight with normal alanine aminotransferase levels) and nine were heterosexuals with raised alanine aminotransferase levels (> 45 U/l) but with no history of blood transfusion or ethanol intake (< 80 g daily). In all but five cases, liver biopsy was performed in subjects with persistent elevated alanine aminotransferase levels. In 10 out of 24 cases (41.66%) hepatitis B virus infection was demonstrated by polymerase chain reaction or immunohistochemistry, and when results from both procedures were available (n = 11) hepatitis B virus infection was detected in 63.63% of the subjects. The only clinical feature associated with HBV infection was the presence of persistent elevated alanine aminotransferase levels (p < 0.05). In conclusion, persistent isolated anti-HBc reactivity may be a relatively common serologic pattern for hepatitis B virus occult infection, at least in patients with chronic liver disease.  相似文献   

18.
19.
The roles of IgE in protective immunity and eosinophilia in Angiostrongylus costaricensis infection were examined by comparing IgE-deficient SJA/9 mice and IgE-producing SJL/J mice. In primary infection, mean total IgE levels increased to a maximum of 390 ng/ml, which was more than 10 times greater than the 29 ng/ml measured preinfection in SJL/J mice but less than the 10 ng/ml found in SJA/9 mice throughout the experiment. Immune defense as determined by recovery of adult worms and eosinophilia were similar in SJL/J and SJA/9 mice. Protective immunity was induced by infection with A. costaricensis followed by treatment with levamisole for 4-6 days postinfection. After the challenge infection, the numbers of adult worms and eosinophils in SJA/9 mice were not significantly different from those in SJL/J mice. Anti-A. costaricensis IgE antibody was not detected in either strain of mice during the experiment. These results indicate that A. costaricensis infection induced the production of IgE not specific for parasite antigens in IgE-producing mice. Potentiated nonspecific IgE played no significant role in immune defense and eosinophilia.  相似文献   

20.
The adsorption of (3)H-labeled Streptococcus mutans 6715 cells to disks of hydroxyapatite (HA) was studied. The number of streptococci that adsorbed was logarithmically related to the concentration of cells available up to at least 2 x 10(8) per ml; equilibrium occurred within 45 min. Assay reliability was verified by direct scanning electron microscopic counts. Untreated HA disks exposed to buffered saline (PBS)-suspended streptococci at a concentration of 1.1 x 10(8) per ml absorbed 3.2 x 10(6) cells per cm(2); approximately 3% of the surface area was, therefore, occupied by adsorbed organisms. The presence of adsorbed salivary components on HA reduced the number of attaching S. mutans cells by half. When S. mutans cells were suspended in saliva to mimic conditions existing in the mouth, the number of streptococci adsorbing to saliva-treated HA was reduced more than 30-fold compared to untreated HA. Approximately one-half of the streptococci adsorbed to untreated or to saliva-treated HA disks could be desorbed over a 4-h period with 0.067 M phosphate buffer. S. mutans cells exposed to sucrose to permit extracellular polysaccharide synthesis before or during adsorption attached in fewer numbers to both saliva-treated and untreated HA than PBS-treated organisms. When S. mutans cells adsorbed on untreated HA were exposed to sucrose, fewer organisms could be desorbed; thus, in situ polysaccharide synthesis promoted their more firm attachment to untreated HA. However, when saliva-suspended streptococci were adsorbed to saliva-treated HA surfaces, exposure to sucrose before or subsequent to adsorption did not promote more firm attachment. Evidently, the powerful adherence-inhibiting and desorptive effects of salivary components overshadowed any promoting effects attributable to glucan synthesis from sucrose. Similarly, no differences were noted in the desorption of S. mutans cells from human teeth after exposure to sucrose, glucose, or PBS relative to a strain of Streptococcus mitis (S. mitior). Thus, no evidence was obtained to support the hypothesis that glucan synthesis from sucrose was essential for, or promoted, the attachment of S. mutans cells to HA surfaces exposed to saliva or to the smooth surfaces of human teeth.  相似文献   

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