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61.
全沟硬蜱在黑龙江小兴安岭莱姆病螺旋体传播中的作用   总被引:2,自引:0,他引:2  
目的:探讨全沟硬蜱在莱姆病螺旋体传播中的作用。方法:用布旗法在林区草地采蜱,并分类鉴定;用直接荧光抗体法检查蜱类中肠带菌情况,并分离菌株。结果:全沟硬蜱为当地优势蜱种,人群发病与该蜱叮咬率密切相关;该蜱中肠带菌率为40%,并从14组(70只)蜱中分离出2株莱姆病螺旋体;新分离株的单克隆抗体反应与国内分离株M7相同,而与美国菌株B31有区别。结论:当地全沟硬蜱是莱姆病螺旋体的主要生物媒介。  相似文献   
62.
中国莱姆病螺旋体PD91重组OspC的鉴定和抗原性检测   总被引:3,自引:0,他引:3       下载免费PDF全文
目的 重组中国莱姆病螺旋体PD91外膜蛋白C(OspC)并在大肠埃希菌中表达,用于早期莱姆病诊断的研究。方法 用聚合酶链反应(PCR)扩增出PD91外膜蛋白C基因,定向克隆到表达载体PET-llD,构建重组质粒PET-llD-ospC。用PCR、限制性内切酶分析及序列测定等方法鉴定重组质粒。用Western Blot检测其抗原性。结果 OspC基因被正确克隆到表达载体PET-llD中。序列测定结果证实与国外已报道的序列存在一定的差异。OspC具有强抗原性。结论 该项研究为国内莱姆病的早期特异性诊断的研究奠定了基础。  相似文献   
63.
从四川白腹鼠体内分离出莱姆病螺旋体   总被引:10,自引:3,他引:7  
1991年5~6月,我们在四川省南川县调查莱姆病动物宿主,从白腹鼠肾脏分离出1株螺旋体(SR1)。用种和属单克隆抗体对SR1菌株进行间接免疫荧光抗体试验,该菌株与美国B_(31)菌株的单克隆反应基本相似,但外表蛋白抗原并不完全一致,表明该鼠可能是我田南方莱姆病螺旋体的重要动物宿主。从白腹鼠分离出莱姆病螺旋体,在国内外属首次报告。  相似文献   
64.
65.
Bird-facilitated introduction of ticks and associated pathogens is postulated to promote invasion of tick-borne zoonotic diseases into urban areas. Results of a longitudinal study conducted in suburban Chicago, Illinois, USA, during 2005–2010 show that 1.6% of 6,180 wild birds captured in mist nets harbored ticks. Tick species in order of abundance were Haemaphysalis leporispalustris, Ixodes dentatus, and I. scapularis, but 2 neotropical tick species of the genus Amblyomma were sampled during the spring migration. I. scapularis ticks were absent at the beginning of the study but constituted the majority of ticks by study end and were found predominantly on birds captured in areas designated as urban green spaces. Of 120 ticks, 5 were infected with Borrelia burgdorferi, spanning 3 ribotypes, but none were infected with Anaplasma phagocytophilum. Results allow inferences about propagule pressure for introduction of tick-borne diseases and emphasize the large sample sizes required to estimate this pressure.  相似文献   
66.
Ehrlichia minasensis is a new pathogenic bacterial species that infects cattle, and Borrelia theileri causes bovine borreliosis. We detected E. minasensis and B. theileri DNA in cattle from southwestern Colombia by using PCR. E. minasensis and B. theileri should be considered potential etiologies of febrile syndrome in cattle from Colombia.  相似文献   
67.
Previous studies have shown that monocytes can be ‘trained’ or tolerized by certain stimuli to respond stronger or weaker to a secondary stimulation. Rewiring of glucose metabolism was found to be important in inducing this phenotype. As we previously found that Borrelia burgdorferi (B. burgdorferi), the causative agent of Lyme borreliosis (LB), alters glucose metabolism in monocytes, we hypothesized that this may also induce long-term changes in innate immune responses. We found that exposure to B. burgdorferi decreased cytokine production in response to the TLR4-ligand lipopolysaccharide (LPS). In addition, B. burgdorferi exposure decreased baseline levels of glycolysis, as assessed by lactate production. Using GWAS analysis, we identified a gene, microfibril-associated protein 3-like (MFAP3L) as a factor influencing lactate production after B. burgdorferi exposure. Validation experiments proved that MFAP3L affects lactate- and cytokine production following B. burgdorferi stimulation. This is mediated by functions of MFAP3L, which includes activating ERK2 and through activation of platelet degranulation. Moreover, we showed that platelets and platelet-derived factors play important roles in B. burgdorferi-induced cytokine production. Certain platelet-derived factors, such chemokine C-X-C motif ligand 7 (CXCL7) and (C-C motif) ligand 5 (CCL5), were elevated in the circulation of LB patients in comparison to healthy individuals.  相似文献   
68.
Borreliosis is an endemic infection in Denmark. Recent serosurveys have indicated that human anaplasmosis may be equally common. The aim of this study was to look for Anaplasma phagocytophilum and related pathogens in Ixodes ricinus ticks and estimate their prevalence, compared to Borrelia, using PCR. Ticks were collected from three locations in Denmark: Jutland, Funen, and Bornholm. Ticks from Jutland and Funen were analysed individually, ticks from Bornholm were analysed in pools of 20. A. phagocytophilum was found in ticks from all areas. A. phagocytophilum was found in 23.6% of ticks from Jutland and Funen, while 11% were positive for Borrelia burgdorferi. The Borrelia genotype B. afzelii was most prevalent, followed by B. valaisiana, B. burgdorferi s.s. and B. garinii.A. phagocytophilum was found in 14.5% of nymphs and 40.5% of adult ticks, while Borrelia was found in 13% of nymphs and 8% of adult ticks. The difference in prevalence between Anaplasma and Borrelia in adult ticks supports the idea that their maintenance cycles in nature may be different. Ticks were also infected with Rickettsia helvetica. Our study indicates that A. phagocytophilum prevalence in ticks in Denmark is as high as Borrelia prevalence and that human anaplasmosis may be unrecognized.  相似文献   
69.
广东首次分离到莱姆病螺旋体   总被引:3,自引:0,他引:3  
目的:分离莱姆病螺旋体。方法:鼠、蜱标本接种BSK培养基,分离病原体与单克隆抗体进行间接免疫荧光试验。结果:用BSK培养基分离49只野鼠和250匹蜱,从1只白腹巨鼠胚胎分离到1株螺旋体(LPR30)。结论:鉴定为莱姆病螺旋体  相似文献   
70.
Neuroborreliosis   总被引:1,自引:0,他引:1  
Neuroborreliosis, a manifestation of infection with the spirochete Borellia burgdorferi, has become the most frequently recognised arthropod-borne infection of the nervous system in Europe and the USA. The best criterion of an early infection with B. burgdorferi is erythema migrans (EM), but this is present in only about 40–60 % of patients with validated borreliosis. Therefore use of the duration of the disease as a classification criterion for neuroborreliosis is increasing, the chronic form being distinguished from the acute when symptoms persist for more than 6 months. The diverse manifestations of neuroborreliosis require that it be included in the differential diagnosis of many neurological disorders. In Europe, meningopolyradiculoneuritis (Bannwarth’s syndrome) represents the most common manifestation of acute neuroborreliosis, with the facial nerve being affected much more frequently than the other cranial nerves. Clinical symptoms affecting the central nervous system are rarely observed and then mostly in chronic courses. By far the most common manifestation of chronic neuroborreliosis is encephalomyelitis with spastic-ataxic disturbances and a disturbance of micturition. The current diagnosis of neuroborreliosis is a clinical one, which has to be confirmed by laboratory testing. In most patients, examination of the cerebrospinal fluid (CSF) reveals lymphocytic pleocytosis, damage to the blood-CSF-barrier and an intrathecal synthesis immunoglobulin (Ig) M, IgG, and sometimes IgA. Confirmation of a borrelial infection of the nervous system requires demonstration of an intrathecal synthesis of borrelial-specific antibodies in the CSF or detection of borrelial DNA in the CSF by polymerase chain reaction (PCR). There is no generally accepted therapeutic regime for the treatment of neuroborreliosis, but recent studies have shown ceftriaxone 2 g/day and cefotaxime 6 g/day to be effective in acute and chronic courses. Penicillin G 20 mega units/day and doxycycline 200 mg/day may be suitable for uncomplicated meningopolyneuritis, without involvement of the central nervous system. The duration of treatment – at least 2 weeks in the acute forms and 3 weeks in the chronic forms of neuroborreliosis – is very important for successful treatment. Corticosteroids are recommended only for patients with severe pain that does not respond to antibiotics an analgesics. Received: 24 December 1997 Accepted: 6 January 1998  相似文献   
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