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1.
Invariable region (IR)(6), an immunodominant conserved region of VlsE, the antigenic variation protein of Borrelia burgdorferi, is currently used for the serologic diagnosis of Lyme disease in humans and canines. A longitudinal assessment of anti-IR(6) antibody levels in B. burgdorferi-infected rhesus monkeys revealed that this level diminished sharply after antibiotic treatment (within 25 weeks). In contrast, antibody levels to P39 and to whole-cell antigen extracts of B. burgdorferi either remained unchanged or diminished less. A longitudinal analysis in dogs yielded similar results. In humans, the anti-IR(6) antibody titer diminished by a factor of > or =4 in successfully treated patients and by a factor of <4 in treatment-resistant patients. This result suggests that the quantification of anti-IR(6) antibody titer as a function of time should be investigated further as a test to assess response to Lyme disease therapy or to determine whether a B. burgdorferi infection has been eliminated.  相似文献   

2.
In order to learn the heterogeneity of the DNA of B. burgdorferi s.l. and the prevalence of co-infections of B. burgdorferi s.l. genospecies in the populations of I. ricinus, collected in north-western Poland, the nested PCR method was applied, a fragment of the fla gene being used as a marker. Basing on the prevalence data of B. burgdorferi s.l. DNA in I. ricinus ticks in 8 sampling sites during 1998-2001, it may be stated that a risk of contracting Lyme disease exists in forested areas of north-western Poland, the highest in relation to B. burgdorferi s.s. (76.3% infected ticks), lower by B. garinii (2% infected ticks), and minimal threat being posed by B. afzelii (0.3%). I. ricinus ticks collected in north-western Poland pose a risk of contracting double infection by B. burgdorferi s.l. genospecies, i.e. B. burgdorferi s.s. with B. garinii, and B. burgdorferi s.s. with B. afzelii. The north-western part of Poland represents an endemic area for B. burgdorferi s.l.  相似文献   

3.
It has been suggested that a <4-fold decline in the immunoglobulin G (IgG) antibody response to the VlsE sixth invariant region peptide of Borrelia burgdorferi within 6 months after antibiotic treatment may indicate spirochetal persistence in Lyme disease. We studied the response to this peptide in 77 patients with early or late disease, for whom archival samples were available at the time of antibiotic treatment and approximately 6 months or years later. Eight (33%) of the 24 patients with early manifestations and 18 (86%) of the 21 patients with late manifestations had a <4-fold decline in IgG anti-VlsE titers approximately 6 months after successful antibiotic treatment. Of 32 additional patients, 13 (50%) with early manifestations and 5 (83%) with late manifestations still had positive anti-VlsE titers 8-15 years after successful antibiotic treatment. We conclude that persistence of the anti-VlsE antibody response for months or years after antibiotic treatment cannot be equated with spirochetal persistence in Lyme disease.  相似文献   

4.
Ticks are recently regarded as ones of the most important vectors of emerging diseases. One of these diseases is human granulocytic ehrlichiosis caused by obligatory intracellular microorganism recently named as Anaplasma phagocytophilum. 334 sera from forestry workers and 56 sera from blood donors (as a control group) were collected and examined for antibodies to A. phagocytophilum and B. burgdorferi. The antibodies were found statistically more frequently in sera from foresters compared to sera of the control group, both to A. phagocytophilum (19.8% vs. 5.4%, p < 0.001) and B. burgdorferi (32.0% vs. 7.1%, p < 0.01). Only 15 sera (4.5%) were found positive for both examined bacteria suggesting inhibition of coexistence although it was not statistically significant. No correlation was found between percentages of antibodies to A. phagocytophilum and to B. burgdorferi from different locations.  相似文献   

5.
No data are available on the role of badgers in the ecology of Lyme borreliosis spirochetes in Europe. In a recent study describing validation of a molecular method allowing host DNA identification and Borrelia burgdorferi sensu lato detection in Ixodes ricinus, the simultaneous presence of B. afzelii DNA and of European badger (Meles meles) DNA was detected in I. ricinus ticks in Switzerland. This suggested that badgers might be reservoir hosts for B. afzelii. Here, we present results obtained in a study on badgers conducted in 1996-1997. Thirty-one tissue samples (ear biopsy: n = 25, aspiration fluid: n = 6) from 8 badgers were placed in BSK medium to isolate B. burgdorferi sensu lato and were then examined by polymerase chain reaction/restriction fragment length polymorphism (PCR/RFLP). Globally, six Borrelia isolates (6/31, 19.4%) were obtained from 3/8 (37.5%) badgers. These isolates were identified as B. afzelii (n = 3) and B. valaisiana (n = 3).  相似文献   

6.
The European rodents Clethrionomys glareolus (bank vole) and Apodemus flavicollis (yellow-necked-mouse) are important hosts of the tick species Ixodes ricinus, the main European vector of Borrelia burgdorferi. We have addressed the question whether or not these tick hosts develop resistance to I. ricinus larvae. C. glareolus and A. flavicollis were exposed to 40 I. ricinus larvae for five consecutive times at two week intervals. Resistance was tested by the following parameters: percentage of ticks fully engorged, time of attachment, engorgement index, percentage of recovered ticks and proportion of larvae moulting to nymphs. Repeated infestation ofC. glareolus resulted in progressive and significant reductions in the percentage of fully engorged ticks, the time of attachment of partially engorged ticks, the scutal index of partially engorged ticks and the moulting success. In contrast, repeatedly infested A. flavicollis did not acquire resistance to larval I. ricinus. Effects of resistance in C glareolus could be partially disrupted by treatment with the immunosuppressive agent, cyclosporin A (CsA), indicating that T helper cells participate in the immune responses to tick bites. The data suggest that acquired immunity to I. ricinus larvae in C. glareolus is a density-dependent factor regulating natural tick burdens and that it may have an impact on the transmission cycle of B. burgdorferi in Central Europe.  相似文献   

7.
目的了解吉林珲春地区家畜中斑点热、莱姆病及其复合感染的情况。方法应用间接免疫荧光法检测家畜血清中斑点热群立克次体和伯氏疏螺旋体的IgG抗体。结果牛血清中斑点热感染率为18.0%,莱姆病感染率为27.5%,复合感染率为9.5%;羊血清中斑点热感染率为19.2%,莱姆病感染率为31.5%,复合感染率为12.8%。结论吉林珲春地区家畜中广泛存在斑点热和莱姆病的复合感染。  相似文献   

8.
To identify potential zoonotic reservoirs of pathogenic leptospires in the Peruvian Amazon basin, wild mammals were trapped from July 1997 to December 1998 near the city of Iquitos. After extraction of nucleic acids from animal kidneys, DNA of pathogenic leptospires was identified by polymerase chain reaction (PCR) assays using one of two primer sets, one amplifying a region of the 23S rRNA gene, and the other amplifying a gene fragment specific for Leptospira spp (G1/G2 primers). Overall, 29% (40 of 136) of the mammals tested showed evidence of renal infection by Leptospira spp., including 20% (13 of 64) of the rodents, 39% (20 of 51) of the marsupials, and 35% (7 of 20) of the chiropterans (bats). Marsupials and chiropterans were implicated as more significant reservoir hosts of leptospires pathogenic to humans than previously recognized.  相似文献   

9.
During the period 2001-2002, 1098 Ixodes ricinus ticks were collected at forest sampling sites and the degree of their infection with Borrelia burgdorferi spirochetes was determined by means of polimerase chain reaction (PCR). The presence of Borrelia burgdorferi genetic material was noted in 69 cases (6.3%). It was confirmed that the frequency of infection of adult forms of ticks (males and females) was nearly twice as high as nymphs. The highest degree of infection was observed in females--9.5%. The degree of infection among males and nymphs was smaller--5.9% and 4.4% respectively in individual provinces. The percentage of infected females ranged from 7.9% in the Zamo?? Province to 13.6% in the W?odawa Province. In males, the percentage of infected ticks remained within the range from 3.1% in the Lublin Province to 13.3% in the Lubartów Province.  相似文献   

10.
A highly immunogenic epitope from a conserved COOH-terminal region of the human immunodeficiency virus (HIV) gp120 envelope protein has been identified with antisera from HIV-seropositive subjects and a synthetic peptide (SP-22) containing 15 amino acids from this region (Ala-Pro-Thr-Lys-Ala-Lys-Arg-Arg-Val-Val-Gln-Arg-Glu-Lys-Arg). Peptide SP-22 absorbed up to 100% of anti-gp120 antibody reactivity from select HIV+ patient sera in immunoblot assays and up to 79% of serum anti-gp120 antibody reactivity in competition RIA. In RIA, 45% of HIV-seropositive subjects had antibodies that bound to peptide SP-22. Human anti-SP-22 antibodies that bound to and were eluted from an SP-22 affinity column reacted with gp120 in RIA and immunoblot assays but did not neutralize HIV or inhibit HIV-induced syncytium formation in vitro, even though these antibodies comprised 70% of all anti-gp120 antibodies in the test serum. In contrast, the remaining 30% of SP-22 nonreactive anti-gp120 antibodies did not react with gp120 in immunoblot assays but did not react in RIA and neutralized HIV in vitro. Thus, approximately 50% of HIV-seropositive patients make high titers of nonneutralizing antibodies to an immunodominant antigen on gp120 defined by SP-22. Moreover, the COOH terminus of gp120 contains the major antigen or antigens identified by human anti-gp120 antibodies in immunoblot assays.  相似文献   

11.
To address the issue of whether Borrelia infection can be asymptomatic, blood donors with no history of borreliosis (n = 408) were screened for antibodies against Borrelia burgdorferi. Seropositive individuals (n = 17) were further investigated with respect to Borrelia-specific T-cell reactivity, using an interferon-gamma ELISPOT assay. Anti-Borrelia antibodies as well as Borrelia-specific T-cell responses were evident in 9 asymptomatic donors, strongly supporting a current or previous asymptomatic Borrelia infection.  相似文献   

12.
目的 构建莱姆病螺旋体PD91菌株外膜蛋白C(OspC)的表达载体 ,克隆表达OspC以便用于莱姆病诊断研究。方法 设计引物 ,用PCR从PD91扩增出ospC基因 ,定向克隆到表达载体PGEX - 5X - 1,构建重组质粒。通过PCR、酶切分析及序列测定等方法鉴定重组质粒。结果 ospC基因被正确克隆到表达载体PGEX - 5X - 1中。序列测定结果证实与国外已报道的ospC基因序列同源性在 6 5 %~ 92 %。 结论 OspC的编码基因在不同菌株间的同源性存在较大的差异。PGEX -5X - 1-ospC重组质粒的成功构建 ,为我国莱姆病特异性诊断试剂的研究奠定了基础。  相似文献   

13.
Previous work described an enzootic cycle of Borrelia burgdorferi sensu lato (hereafter referred to as B. burgdorferi) maintained by the rodent Neotoma mexicana and the tick Ixodes spinipalpis in northern Colorado. We investigated the incidence of coinfection among rodents with the agent of human granulocytic ehrlichiosis (aoHGE). aoHGE was detected in 23.5% of 119 rodent spleens examined. Biopsy results indicated that 78 (65.5%) of the 119 rodents were positive for B. burgdorferi, whereas 22 (78.5%) of the 28 animals that harbored aoHGE were also infected with B. burgdorferi. In 14 of 25 I. spinipalpis tick pools, aoHGE was detected by amplifying both the 16s rRNA and p44 gene of aoHGE. The ability of I. spinipalpis to transmit aoHGE was examined in C3H/HeJ mice. aoHGE was detected in their blood 5 days after I. spinipalpis infestation. This study confirms that both B. burgdorferi and aoHGE can be transmitted by I. spinipalpis ticks and that there is a high incidence of coinfection in rodents, predominantly Peromyscus maniculatus and N. mexicana, that inhabit the foothills of northern Colorado.  相似文献   

14.
Previously we demonstrated that Borrelia burgdorferi transmission by Ixodes scapularis suppressed IL-2 and IFN gamma production and promoted IL-4 production in mice. The present studies were conducted to determine whether coinfection with the human granulocytic ehrlichiosis (HE) agent would promote a Th2 cytokine response in mice. Transmission to the spleen of the agent of human granulocytic ehrlichiosis (aoHGE) and B. burgdorferi occurred 4 and 7 days, respectively, after tick infestation. Coinfection synergized to suppress splenic IL-2 production 7-14 days after tick infestion. Transmission of B. burgdorferi or aoHGE alone significantly decreased splenic IFN gamma 4-7 days after tick infestation, while coinfection suppressed IFN gamma production 7-14 days after tick infestation. Splenic IL-4 production was significantly increased 4 days after coinfection, and by day 10, aoHGE plus B. burgdorferi induced greater splenic IL-4 (57.2 pg/ml, 348% of control values) than either organism transmitted alone (aoHGE, 22.7 pg/ml, B. burgdorferi, 25.1 pg/ml). Coinfection enhanced expansion of splenic T cells, CD4+ lymphocytes and B cells while decreasing CD8+ T cells. These data demonstrate that aoHGE and B. burgdorferi, when cotransmitted, suppress a systemic IL-2 and IFN gamma response, while strongly promoting systemic IL-4 production in the susceptible host. The antigen(s) responsible for this polarization are unknown and will be the subject of future studies.  相似文献   

15.
PURPOSE: There is a need for valid and reliable short scales that can be used to assess social networks and social supports and to screen for social isolation in older persons. DESIGN AND METHODS: The present study is a cross-national and cross-cultural evaluation of the performance of an abbreviated version of the Lubben Social Network Scale (LSNS-6), which was used to screen for social isolation among community-dwelling older adult populations in three European countries. Based on the concept of lack of redundancy of social ties we defined clinical cut-points of the LSNS-6 for identifying persons deemed at risk for social isolation. RESULTS: Among all three samples, the LSNS-6 and two subscales (Family and Friends) demonstrated high levels of internal consistency, stable factor structures, and high correlations with criterion variables. The proposed clinical cut-points showed good convergent validity, and classified 20% of the respondents in Hamburg, 11% of those in Solothurn (Switzerland), and 15% of those in London as at risk for social isolation. IMPLICATIONS: We conclude that abbreviated scales such as the LSNS-6 should be considered for inclusion in practice protocols of gerontological practitioners. Screening older persons based on the LSNS-6 provides quantitative information on their family and friendship ties, and identifies persons at increased risk for social isolation who might benefit from in-depth assessment and targeted interventions.  相似文献   

16.
The prevalence of asthma, allergic rhinitis, allergic conjunctivitis, and allergic skin disorders (urticaria and atopic dermatitis) was investigated between the years 1993 and 1994 in the Aegean region of Turkey and was found to be 3.8, 4.6, 12.6, and 19.4%, respectively (Tana? R, Kurug?l Z, Demir E, et al., Cocuk Sa?li?i ve Hast Derg 39:77-85, 1996). The aim of the present study was to determine whether there is a change in the prevalence of allergic diseases in the Aegean region in the last 8 years, based on the comparison of the results using the same method applied in the study mentioned above. Three thousand three hundred seventy children (48.6% male participants and 51.4% female participants) between the ages of 5 and 18 years (mean age, 11.55 +/- 3.34 years) were enrolled in the study. The participants were randomly chosen among children attending primary schools in the cities of the Aegean region. The children completed a questionnaire; and physical examinations, serum-specific immunoglobulin E antibody levels, and peak expiratory flow measurements were done for each of them. Of the children, 21.2% were found to have at least one attack of wheezing whereas the prevalence of asthma was 6.4%. The prevalence of allergic rhinitis, allergic conjunctivitis, and allergic skin disorders (urticaria and atopic dermatitis) were found to be 13.6, 13.2, and 23.7%, respectively. The increase of prevalence for asthma was 2.6%, for allergic rhinitis was 9%, and for allergic conjunctivitis was 0.6%. These data show that the prevalence of allergic diseases, especially respiratory allergy, has increased among schoolchildren from the Aegean region of Turkey.  相似文献   

17.
18.
OBJECTIVE: To determine how expert European thyroidologists assess and treat amiodarone-induced thyrotoxicosis (AIT). DESIGN: Members of the European Thyroid Association (ETA) with clinical interests were asked to answer a questionnaire on the diagnosis and management of AIT. A total of 124 responses were received: 116 from Europe, seven from USA and one from Brazil. After excluding responses coming from the same centre, 101 responses from 24 European countries were analysed, representing approximately 65% of clinically active European ETA members. RESULTS: The majority of respondents (68%) see 1-10 new cases of AIT/year, and AIT seems to be more frequent than amiodarone-induced hypothyroidism in Europe, where in many instances iodine intake is borderline or moderately deficient. A good collaboration with cardiologists exists in most centres, and patients receiving chronic amiodarone treatment are checked for thyroid function most commonly every 4-6 months. When AIT is suspected, a diffuse or nodular goitre is present or in the absence of apparent abnormalities of the thyroid, free thyroxine (FT4), free triiodothyronine (FT3) and TSH are assayed by almost 90% of respondents. Thyroid autoimmunity is evaluated in the initial assessment by > 80%, while evaluation of urinary iodine excretion is unhelpful for > 60%. Most commonly used additional diagnostic procedures include thyroid ultrasonography, particularly colour flow Doppler sonography, and, to a lesser extent, a thyroid uptake scan. If the thyroid gland is apparently normal, measurement of thyroidal radioactive iodine uptake is considered useful by a large proportion of respondents to establish the destructive nature of the process. Differentiation of type I and type II AIT is difficult and, possibly, not correct for 27% of respondents, who believe that mixed (or indefinite) forms are probably more frequent than previously recognized. Approximately 10-20% do not consider amiodarone withdrawal necessary in the therapeutic strategy of AIT, especially if the thyroid gland is apparently normal. Most respondents (82%) treat type I AIT with thionamides, either alone (51%) or in combination with potassium perchlorate (31%), while the preferred treatment for type II AIT is represented by glucocorticoids (46%). Some respondents, in view of diagnostic difficulties, initially treat all cases of AIT with a combination of thionamides and glucocorticoids. After restoration of euthyroidism, ablative therapy is recommended by 34% in type I and only 8% in type II AIT. If amiodarone therapy needs to be reinstituted, prophylactic thyroid ablation is recommended by 65% in type I AIT, while a wait-and-see strategy is adopted by 70% in type II AIT. CONCLUSION: Areas of certainty and uncertainty concerning AIT are present among expert European thyroidologists, both from a diagnostic and a therapeutic standpoint. Diagnostic criteria need to be refined in order to improve therapeutic outcome.  相似文献   

19.
This paper summarizes the opinions of 20 representatives of well-known European centers for adult and pediatric thoracic and cardiovascular surgery regarding the optimal structure and organization of such units. These opinions were collected by means of a questionnaire, and the answers were discussed by the members of the group. Statistical analysis showed a high degree of concordance on the following subjects: The population to be covered by a given center, the relationship between cardiac surgery and cardiology, the minimal number of operations to be performed, the surgical, anaesthesiological and nursing staff, the equipment level required, the surgical training and research, and the cooperation with other centers, Partial concordance of opinions was reached in other aspects, while on some topics widely divergent views were stated, depending, in part, upon regional differences. This material is discussed in detail and we hope it will serve as a guide for the future development in this field both within and outside of Europe.  相似文献   

20.
OBJECTIVES: Our aim was to examine whether circulating oxidized low-density lipoprotein (oxLDL) is a predictor of coronary heart disease (CHD) independent of lipid markers and to compare oxLDL, apolipoprotein B100 (apoB), and total cholesterol (TC)/high-density lipoprotein-cholesterol (HDL-C) ratio as predictors of CHD. BACKGROUND: Measurement of circulating oxLDL with antibody 4E6, has been widely used in many studies; however, few large prospective studies have examined whether this marker is a predictor of CHD independent of lipids and compared oxLDL with other important lipid predictors. METHODS: After 6 years of follow-up among 18,140 men from the HPFS (Health Professionals Follow-up Study) and 8 years among 32,826 women from the Nurses' Health Study who provided blood samples at baseline, we identified incident nonfatal myocardial infarction or fatal CHD in 266 men and 235 women. Each case was matched with two control subjects by age, smoking, and time of blood draw. The oxLDL was measured via enzyme-linked immunosorbent assay with antibody 4E6 against oxidized apoB. RESULTS: Among both men and women, oxLDL was significantly related to risk of CHD in multivariate analysis before adjustment for any lipid markers. However, when oxLDL, LDL cholesterol, HDL-C, and triglycerides were mutually adjusted, oxLDL was no longer predictive. When oxLDL and apoB were mutually adjusted, only apoB was predictive of CHD. Similar results were found when oxLDL and TC/HDL-C ratio were mutually adjusted. CONCLUSIONS: Our results suggest that circulating oxLDL, measured with antibody 4E6, is not an independent overall predictor of CHD after adjustment of lipid markers and is less predictive in development of CHD than apoB and TC/HDL-C ratio.  相似文献   

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