Objective Western blotting （WB;immunoblotting） is a widely used tool for the serodiagnosis of Lyme borreliosis （LB）,but so far,no generally accepted criteria for its performance and interpretation have been establ...Objective Western blotting （WB;immunoblotting） is a widely used tool for the serodiagnosis of Lyme borreliosis （LB）,but so far,no generally accepted criteria for its performance and interpretation have been established in China.The present study was designed to determine the criteria for standardized Western blot for the predominant species of Borrelia burgdorferi sensu lato in China,in which WB was produced with strain PD91 as the representative strain attributed to predominant genospecies Borrelia garinii of Borrelia burgdorferi sensu lato.Methods Approximately 13 bands between 14 and 100 kD were differentiated for strain PD91 by using Gel-Pro analysis software.In a study with 631 serum samples （taken from 127 patients with Lyme borreliosis and 504 controls）,all observed bands were documented.To establish criteria for a positive WB result for strain PD91,receiver operating characteristic （ROC） curves were used.Results The following interpretation criteria were recommended：for IgG,at least one band of P83/100,P58,P39,P30,OspC,P17,P66,and OspA;for IgM,at least one band of P83/100,P58,OspA,P30,OspC,P17 or P41.In addition,syphilis,leptospirosis and other related diseases should be excluded when the positive band is P41 in IgM.For IgG criteria,the sensitivity is 73.2%,the specificity is 99.4% and Youden index is 0.726;for IgM criteria,the sensitivity is 50.6%,the specificity is 93.1% and Youden index is 0.437.Conclusion Standardization of WB assays is necessary for comparison of results from different laboratories.Moreover,the criteria of other genospecies of Borrelia burgdorferi sensu lato should be determined in the future to complete the criteria of WB for the diagnosis of the Lyme disease in China.展开更多
Objective To study the technique of Western blot for the diagnosis of Lyme disease caused by Borrelia afzelii in China and to establish the standard criteria by operational procedure. Methods FP1, which is the represe...Objective To study the technique of Western blot for the diagnosis of Lyme disease caused by Borrelia afzelii in China and to establish the standard criteria by operational procedure. Methods FP1, which is the representative strain of B. afzelii in China, was analyzed by SDS-PAGE, electro transfer and irnmunoblotting assays. The molecular weights of the protein bands of FP1 were analyzed by Gel-Pro analysis software. In a study using 451 serum samples （159 patients with Lyme disease and 292 controls）, all observed bands were recorded. The accuracy of the WB as a diagnostic test was established by using the ROC curve and Youden index. Results Criteria for a positive diagnosis of Lyme disease were established as at least one band of P83/100, P58, P39, OspB, OspA, P30, P28, OspC, P17, and P14 in the IgG test and at least one band of P83/100, P58, P39, OspA, P30, P28, OspC, P17, and P41 in the IgM test. For IgG criteria, the sensitivity, specificity and Youden index were 69.8%, 98.3%, and 0.681, respectively; for IgM criteria, the sensitivity, specificity and Youden index were 47%, 94.2%, and 0.412, respectively.展开更多
Objective To optimize the performance of Pulsed-Field Gel Electrophoresis （PFGE） for the comparison of inter-laboratory results and information exchange of Borrelia burgdorferi subtypingo Methods A panel of 34 strai...Objective To optimize the performance of Pulsed-Field Gel Electrophoresis （PFGE） for the comparison of inter-laboratory results and information exchange of Borrelia burgdorferi subtypingo Methods A panel of 34 strains of B. burgdorferi were used to optimize PFGE for subtyping. In order to optimize the electrophoretic parameters （EPs）, all 34 strains of B. burgdorferi were analyzed using four EPs, yielding different Simpson diversity index （D） values and the epidemiological concordance was also evaluated. Results The EP of a switch time of l s to 25 s for13 h and l s to10 s for 6 h produced the highest D value and was declared to be optimal for Mlul and 5mal PFGE of B. burgdorferi. Mlul and Smal were selected as the first and second restriction enzymes for PFGE subtyping of B. burgdorferi according to discrimination and consistency with epidemiological data. Conclusion PFGE can be used as a valuable test for routine genospecies identification of B burgdorferi.展开更多
Objective Human Lyme Borreliosis （LB）, which is caused by Borrefia burgdorferi sensu lato （B. burgdorferi）, has been identified as a major arthropod-borne infectious disease in China. We aimed to develop a multipl...Objective Human Lyme Borreliosis （LB）, which is caused by Borrefia burgdorferi sensu lato （B. burgdorferi）, has been identified as a major arthropod-borne infectious disease in China. We aimed to develop a multiple locus variable-number tandem repeat （VNTR） analysis （MLVA） assay for the genotyping of Borrelia burgdorJ：eri strains detected in China. Methods B. garinii PBi complete 904.246 kb chromosome and two plasmids （cp26 and Ip54） were screened by using Tandem Repeats Finder program for getting potential VNTR loci, the potential VNTR loci were analyzed and identified with PCR and the VNTR loci data were analyzed and MLVA clustering tree were constrcted by using the categorical coefficient and the unweighted pair-group method with arithmetic means （UPGMA）. Results We identified 5 new VNTR loci through analyzing 47 potential VNTR loci. We used the MLVA protocol to analyse 101 B. burgdorferi strains detected in China and finally identified 51 unique genotypes in 4 major clusters including B. burgdorferi sensu stricto （B.b.s.s）, B. garinii, B. a[zelii, and B. valaisiana, consistent with the current MLSA phylogeny studies. The allele numbers of VNTR-1, VNTR-2, VNTR-3, VNTR-4, and VNTR-5 were 7, 3, 9, 7, and 6. The Hunter-Gaston index （HGI） of five VNTR loci were 0.79, 0.22, 0.77, 0.71, and 0.67, respectively. The combined HGI of five VNTR loci was 0.96. Clustering of the strains of Xinjiang, Inner Mongolia and Heilongjiang was confirmed, and this situation was consistent with the close geographical distribution of those provinces. Conclusion The MLVA protocol esytablished in this study is easy and can show strains＇ phylogenetic relationships to distinguish the strains of Borrelia species. It is useful for further phylogenetic and epidemiological analyses of Borrelia strains.展开更多
AIM： To evaluate the production of reactive oxygen species （ROS） and the expression of inducible nitric oxide synthase （iNOS） in rat isolated Kupffer cells （KCs） stimulated by Leptospira interrogans and Borreli...AIM： To evaluate the production of reactive oxygen species （ROS） and the expression of inducible nitric oxide synthase （iNOS） in rat isolated Kupffer cells （KCs） stimulated by Leptospira interrogans and Borrelia burgdorferi. METHODS： Rat Kupffer cells were separated by perfusion of the liver with 0.05% collagenase, and purified by Percoll gradients. Pudfied Kupffer cells were tested in vitro with alive L.interogans and B. burgdorferi preparations. The production of ROS was determined by chemiluminescence, whereas iNOS protein expression was evaluated by Western blot assay using anti-iNOS antibodies. RESULTS： B. burgdorferi and to a less extent L. interrogans induced ROS production with a peak 35 min after infection. The chemiluminescence signal progressively diminished and was undetectable by 180 min of incubation. Leptospirae and borreliae induced an increased iNOS expression in Kupffer cells that peaked at 6 hours and was still evident 22 h after infection. CONCLUSION： Both genera of spirochetes induced ROS and iNOS production in rat Kupffer cells. Since the cause of liver damage both in leptospiral as well as in borrelial infections are still unknown, we suggest that leptospira and borrelia damage of the liver can be initially mediated by oxygen radicals, and is then maintained at least in part by nitric oxide.展开更多
Polymerase chain reaction (PCR) was used to detect the presence of Barrelia burgdoferi DNA in biological samples from patients with sarcoidosis. The target DNA sequence was of chromosomal origin. The amplified DNA seq...Polymerase chain reaction (PCR) was used to detect the presence of Barrelia burgdoferi DNA in biological samples from patients with sarcoidosis. The target DNA sequence was of chromosomal origin. The amplified DNA sequence was analyzed by agarose gel electrophoresis, PAGE with silver staining, and the identity of amplified DNA was confirmed by restriction enzyme cleavage and DNA-DNA hybridization with a 32P-labelled probe. The assay was sensitive to fewer than two copies of B. burgdorferi genome, even in the presence of a 104-fold excess of human eukaryotic DNA , and was also specific to different B. burgdorferi strains tested. Sera serologically positive to B. burgdcrferi (n=26), bronchoalveolar lavage fluid and supernatant of BALF (n=26) and peripheral blood (n=9) from sarcoidosis patients were tested. The positive rate was low (4/26, 2/26. and 0/9, respectively). It was considered that DNA from B. burgdor ferimay be identified in a minority of patients with sarcoidosis, and it may play a pathogenetic role in such cases. More studies need to be done before advancing the hypothesis of an etiologic role of B. burgdorferi in sarcoidosis.展开更多
A set of universal loop-mediated isothermal amplification （LAMP） primers targeting the flo gene was designed to detect Borrelia burgdorferi sensu lato （B. burgdorferi s.I.） in human samples. The sensitivity of LAM...A set of universal loop-mediated isothermal amplification （LAMP） primers targeting the flo gene was designed to detect Borrelia burgdorferi sensu lato （B. burgdorferi s.I.） in human samples. The sensitivity of LAMP was 20 copies/reaction, and the assay did not detect false positives among 11 other related bacteria. A positive LAMP result was obtained for 9 of the 24 confirmed cases and for 12 of 94 suspected cases. The positive rate of LAMP was the same as that of nested PCR. The LAMP is a useful diagnostic method that can be developed for rapid detection of B. burgdorferi s.I. in human sera. Combination of the LAMP and nested PCR was more sensitive for detecting B. burgdorferi s.I. in human serum samples.展开更多
Objective:To investigate the precise species of tick vector and the Borrelia spirochete pathogen at the Heilongjiang Province international border with Russia.Methods:In dus study,ticks were collected from 12 Heilongj...Objective:To investigate the precise species of tick vector and the Borrelia spirochete pathogen at the Heilongjiang Province international border with Russia.Methods:In dus study,ticks were collected from 12 Heilongjiang border crossings(including grasslands,shrublands,forests,and plantantions) to determine the rate and species type of spirochete-infected ticks and the most prevalent spirochete genotypes.Results:The ticks represented three genera and four species of the Ixodidae family[Ixodes persidcatus,Dermacentor silvarum,Haemapkysalis concinna and Haemaphysalis japonica].Ixodes persulcatus had the highest amount of Borrelia burgdorferi sensu lata infection of 25.6%and the most common species of Borrelia isolated from Ixodes persulcatus mas Borrelia garinii,strain PD91.Conclusions:Our results suggest that Borrelia garinii PD91- infected Ixodes persulcatus may be the principal cause of Lyme disease in the border crossing areas of Heilongjiang Province.展开更多
Objective To study the polymorphism in P66 and its human B-cell epitopes of Borrelia burgdorferi strains in China.Methods Polymerase chain reaction(PCR)and sequencing were used to obtain the P66 sequences of59 Chinese...Objective To study the polymorphism in P66 and its human B-cell epitopes of Borrelia burgdorferi strains in China.Methods Polymerase chain reaction(PCR)and sequencing were used to obtain the P66 sequences of59 Chinese B.burgdorferi.Then the sequences were analyzed by MEGA 5.10 software and compared with the human B-cell epitope sequences from the Immune Epitope Database(IEDB)based on the reference strain of each genotype.Results Results showed that genetic and amino acid diversity presented in the 66 kD protein of all 59 Chinese strains,especially in Borrelia garinii(B.g)and Borrelia afzelii(B.a)strains.B.g strains were divided into three subclusters and two scattered strains JC1-7 and JC2-2 according to the amino acid sequences of P66.The P66 sequences of 15 Xinjiang strains represented by XI91-12 in the B.g subcluster1,changed from CAA to TAA codon at 508 aa position,resulting in early termination.Bases A and C were inserted at sequence position 1523 bp of strains FP1,LB20,LB21,and SZ21 in the B.a genotype,which resulted to early termination at position 511 aa.G base was inserted at 438 bp of LIP94-11 strain,which led to early termination at position 172 aa.Conclusion In P66 of 59 Chinese strains,polymorphisms were widely distributed.More importantly,the P66 amino acid sequences of B.g strains had a certain regional character.One of the characteristics of Xinjiang B.g isolates might be the variation at the 508 aa location in 15 Xinjiang B.g strains,which may be related to the strains’pathogenicity in this area.展开更多
Worldwide, wild birds play a vital role in the dispersal of ticks that harbour tick-borne pathogens, including Borrelia burgdorferi, the Lyme disease bacterium. Using PCR testing, we found 124 (31%) of 405 ticks (4 sp...Worldwide, wild birds play a vital role in the dispersal of ticks that harbour tick-borne pathogens, including Borrelia burgdorferi, the Lyme disease bacterium. Using PCR testing, we found 124 (31%) of 405 ticks (4 species), which were collected from 21 species of birds in far-western Canada, to be infected with B. burgdorferi. Transstadial transmission of B. burgdorferi occurred from larva to nymph, plus nymph to adult, in the avian coastal tick, Ixodes auritulus, collected from songbirds in British Columbia (B.C). Collectively, all 3 motile life stages (larva, nymph, adult) of this tick had an infection prevalence of 31% for B. burgdorferi, which suggests vector competency. A Pacific Wren was highly infested with I. auritulus immatures, and 20 (44%) of 45 ticks (2 nymphs, 43 larvae) were infected with B. burgdorferi. This heavy infestation shows the high potential to initiate a new population of ticks and to disseminate Lyme spirochetes. Epidemiologically, B. burgdorferi-infected I. auritulus larvae collected from the Spotted Towhee, Swainson’s Thrush, Pacific Wren, and Fox Sparrow suggest that these avian hosts act as reservoirs for B. burgdorferi. In this study, the western blacklegged tick, Ixodes pacificus, and Ixodes spinipalpis played a limited role in the enzootic transmission cycle of B. burgdorferi along coastal B.C. We document the first record of I. spinipalpis on a bird in Alberta. Because songbirds widely disperse Lyme disease vector ticks, primary health providers and the general public must be vigilant that outdoors people may be bitten by B. burgdorferi-infected ticks throughout far-western Canada.展开更多
There are several factors involved in the ability of Borrelia burgdorferi to retain a persistent infection within a mammalian host. These factors of immune evasion include regulation of membrane proteins, variable epi...There are several factors involved in the ability of Borrelia burgdorferi to retain a persistent infection within a mammalian host. These factors of immune evasion include regulation of membrane proteins, variable epitopes of surface proteins, protection against the immune system through tick saliva, the ability to migrate to regions where it is not exposed to the immune system or antibiotics, invagination or invasion within various cells, pleomorphic forms, and the potential to produce biofilms. The window of conventional treatment for Lyme disease is short and has the potential to display different symptoms depending on the strain of Borrelia bugdorferi. These symptoms are dependent on the localization of Borrelia burgdorferi which correlates to the significance of diagnosing Lyme disease early to prevent such a spread throughout the body. Such complications of Borrelia burgdorferi may demand new clinical treatment discoveries for patient fighting the chronic form.展开更多
Chronic Lyme disease is predicated by an infection with Borrelia burgdorferi via tick vector. B. burgdorferi has been extensively researched with regard to its genome and cell biology. There are many unique characteri...Chronic Lyme disease is predicated by an infection with Borrelia burgdorferi via tick vector. B. burgdorferi has been extensively researched with regard to its genome and cell biology. There are many unique characteristics to the bacteria itself;however, serological diagnostics and diagnosis based on symptoms can be complicated and potentially misleading. Other promising diagnostics were also evaluated in this review. Treatment of the chronic Lyme disease can be complicated and at times ineffective. The purpose of this review is to examine B. burgdorferi from a biological and clinical perspective.展开更多
To investigate the correlation between sarcoidosis and Borrelia burgdorferi (Bb ) infection , flagella DNA of Bb were detected in 23 granulomatous tissue specimens from patients with confirmed sarcoidosis using polym...To investigate the correlation between sarcoidosis and Borrelia burgdorferi (Bb ) infection , flagella DNA of Bb were detected in 23 granulomatous tissue specimens from patients with confirmed sarcoidosis using polymerase chain reaction in siju technique (in situ PCR) and the antibodies to Bb were examined in 55 serum samples obtained from the patients by indirect immunoflurescence assays. Our data presented that:(1) None of granulomatous tissues was found to have Bb DNA in 23 tissue samples. (2) Thirty of 55 (54. 6% ) patients with sarcoidosis were found antibodies to Bb positive ,in contrast ,six of 60 (10%) normal subjects had antibodies against Bb ,the positive rate was remarkably higher in patient group than that in healthy group (P<0. 005) . The results suggest that Bb might not be the causative agent of sarcoidosis.the elevated titres of serum antibodies against Bb in patients with sarcoidosis is a nonspecific response.展开更多
The sera of 180 human samples were tested for the presence of antibodies against Borrelia burgdorferi using the ELISA （enzyme-linked immunosorbent assay） technique. Out of 180 sero-samples, 46 （25.55%） were positi...The sera of 180 human samples were tested for the presence of antibodies against Borrelia burgdorferi using the ELISA （enzyme-linked immunosorbent assay） technique. Out of 180 sero-samples, 46 （25.55%） were positive. Females of the age range 18-35 years had the highest rate of sero-positive samples 14 （38.88%）, while the highest percentage of sero-negative samples was found in males of the age range 50-80 years. The other sero-positive samples were： 6 （26.08%）, 6 （25%） and 3 （11.53%） in males of ages between 18-35, 35-50 and 50-80 years, respectively, and 11 （29.72%） and 6 （17.64%） in females in the age ranges 35-50 and 50-80 years, respectively. The mean concentration of Anti- B. burgdorferi antibody was higher （16.7 U/mL） when compared with mean concentration of normal value （5.5 U/mL）, P 〈 0.001.展开更多
We document the first record of Borrelia americana in Canada. This Borrelia was detected in an avian coast tick, Ixodes auritulus (Acari: Ixodidae), collected from a Varied Thrush, Ixoreus naevius, along coastal Briti...We document the first record of Borrelia americana in Canada. This Borrelia was detected in an avian coast tick, Ixodes auritulus (Acari: Ixodidae), collected from a Varied Thrush, Ixoreus naevius, along coastal British Columbia. Using real-time PCR and DNA sequencing of the flagellin gene, we determined that the borrelial amplicon from the I. auritulus nymph was 99% homologous with B. americana type strain SCW-41. Because patients infected with B. americana can be seronegative for Lyme disease, medical professionals should be willing to pursue molecular analyses and consider treatment for patients with Lyme disease-like symptoms.展开更多
God has created many miraculous creature;ticks are one of them. Borrelia burgdorferi is a bacterium that lives into the gut of ticks. When such ticks feed upon the blood of Ticks and other livestock, bacteria are tran...God has created many miraculous creature;ticks are one of them. Borrelia burgdorferi is a bacterium that lives into the gut of ticks. When such ticks feed upon the blood of Ticks and other livestock, bacteria are transferred into their blood stream of these hosts. A disease is caused into human beings if such infected tick bites humans that are called as Lyme disease. This review will help to have a keen study on the cause, sign, symptoms, prevention and management of this disease.展开更多
To study the genetic characterization of four strains of Borrelia burgdorferi isolated in China. PCR technique was used to amplify the 5S-23S rRNA intergenic spacer DNA from the whole cellular DNA of isolated GXLD-4, ...To study the genetic characterization of four strains of Borrelia burgdorferi isolated in China. PCR technique was used to amplify the 5S-23S rRNA intergenic spacer DNA from the whole cellular DNA of isolated GXLD-4, 9, 18 and Chang 14, and then the amplified products were cloned into plasmid pGEM-T Easy and sequenced. It was found that the 5S-23S rRNA intergenic spacer DNA of the four isolates was 242?bp, revealing the nucleotide sequence identity of more than 99%. The four isolates had higher sequence identify with Borrelia valaisiana than with other genetic groups. These four isolates most likely belong to Borrelia valaisiana genomic group.展开更多
基金supported by the "Tenth Five-Year Plan" project of research on the specific diagnosis method for the Lyme disease. 2001BA705B07
文摘Objective Western blotting （WB;immunoblotting） is a widely used tool for the serodiagnosis of Lyme borreliosis （LB）,but so far,no generally accepted criteria for its performance and interpretation have been established in China.The present study was designed to determine the criteria for standardized Western blot for the predominant species of Borrelia burgdorferi sensu lato in China,in which WB was produced with strain PD91 as the representative strain attributed to predominant genospecies Borrelia garinii of Borrelia burgdorferi sensu lato.Methods Approximately 13 bands between 14 and 100 kD were differentiated for strain PD91 by using Gel-Pro analysis software.In a study with 631 serum samples （taken from 127 patients with Lyme borreliosis and 504 controls）,all observed bands were documented.To establish criteria for a positive WB result for strain PD91,receiver operating characteristic （ROC） curves were used.Results The following interpretation criteria were recommended：for IgG,at least one band of P83/100,P58,P39,P30,OspC,P17,P66,and OspA;for IgM,at least one band of P83/100,P58,OspA,P30,OspC,P17 or P41.In addition,syphilis,leptospirosis and other related diseases should be excluded when the positive band is P41 in IgM.For IgG criteria,the sensitivity is 73.2%,the specificity is 99.4% and Youden index is 0.726;for IgM criteria,the sensitivity is 50.6%,the specificity is 93.1% and Youden index is 0.437.Conclusion Standardization of WB assays is necessary for comparison of results from different laboratories.Moreover,the criteria of other genospecies of Borrelia burgdorferi sensu lato should be determined in the future to complete the criteria of WB for the diagnosis of the Lyme disease in China.
基金supported by the 12th Five-Year Major National Science and Technology Projects of China (No.2011ZX10004-001)Natural Science Foundation of China (31100105)
文摘Objective To study the technique of Western blot for the diagnosis of Lyme disease caused by Borrelia afzelii in China and to establish the standard criteria by operational procedure. Methods FP1, which is the representative strain of B. afzelii in China, was analyzed by SDS-PAGE, electro transfer and irnmunoblotting assays. The molecular weights of the protein bands of FP1 were analyzed by Gel-Pro analysis software. In a study using 451 serum samples （159 patients with Lyme disease and 292 controls）, all observed bands were recorded. The accuracy of the WB as a diagnostic test was established by using the ROC curve and Youden index. Results Criteria for a positive diagnosis of Lyme disease were established as at least one band of P83/100, P58, P39, OspB, OspA, P30, P28, OspC, P17, and P14 in the IgG test and at least one band of P83/100, P58, P39, OspA, P30, P28, OspC, P17, and P41 in the IgM test. For IgG criteria, the sensitivity, specificity and Youden index were 69.8%, 98.3%, and 0.681, respectively; for IgM criteria, the sensitivity, specificity and Youden index were 47%, 94.2%, and 0.412, respectively.
基金supported by the National Natural Science Foundation of China (NSFC)(31100105)the 12th Five-Year Major National Science and Technology Projects of China(No.2012ZX10004219-007)
文摘Objective To optimize the performance of Pulsed-Field Gel Electrophoresis （PFGE） for the comparison of inter-laboratory results and information exchange of Borrelia burgdorferi subtypingo Methods A panel of 34 strains of B. burgdorferi were used to optimize PFGE for subtyping. In order to optimize the electrophoretic parameters （EPs）, all 34 strains of B. burgdorferi were analyzed using four EPs, yielding different Simpson diversity index （D） values and the epidemiological concordance was also evaluated. Results The EP of a switch time of l s to 25 s for13 h and l s to10 s for 6 h produced the highest D value and was declared to be optimal for Mlul and 5mal PFGE of B. burgdorferi. Mlul and Smal were selected as the first and second restriction enzymes for PFGE subtyping of B. burgdorferi according to discrimination and consistency with epidemiological data. Conclusion PFGE can be used as a valuable test for routine genospecies identification of B burgdorferi.
基金supported by Natural Science foundation(Grant No.31100105)China Mega-Project for Infectious Disease(2012ZX10004-215 and 2013ZX10004221)
文摘Objective Human Lyme Borreliosis （LB）, which is caused by Borrefia burgdorferi sensu lato （B. burgdorferi）, has been identified as a major arthropod-borne infectious disease in China. We aimed to develop a multiple locus variable-number tandem repeat （VNTR） analysis （MLVA） assay for the genotyping of Borrelia burgdorJ：eri strains detected in China. Methods B. garinii PBi complete 904.246 kb chromosome and two plasmids （cp26 and Ip54） were screened by using Tandem Repeats Finder program for getting potential VNTR loci, the potential VNTR loci were analyzed and identified with PCR and the VNTR loci data were analyzed and MLVA clustering tree were constrcted by using the categorical coefficient and the unweighted pair-group method with arithmetic means （UPGMA）. Results We identified 5 new VNTR loci through analyzing 47 potential VNTR loci. We used the MLVA protocol to analyse 101 B. burgdorferi strains detected in China and finally identified 51 unique genotypes in 4 major clusters including B. burgdorferi sensu stricto （B.b.s.s）, B. garinii, B. a[zelii, and B. valaisiana, consistent with the current MLSA phylogeny studies. The allele numbers of VNTR-1, VNTR-2, VNTR-3, VNTR-4, and VNTR-5 were 7, 3, 9, 7, and 6. The Hunter-Gaston index （HGI） of five VNTR loci were 0.79, 0.22, 0.77, 0.71, and 0.67, respectively. The combined HGI of five VNTR loci was 0.96. Clustering of the strains of Xinjiang, Inner Mongolia and Heilongjiang was confirmed, and this situation was consistent with the close geographical distribution of those provinces. Conclusion The MLVA protocol esytablished in this study is easy and can show strains＇ phylogenetic relationships to distinguish the strains of Borrelia species. It is useful for further phylogenetic and epidemiological analyses of Borrelia strains.
文摘AIM： To evaluate the production of reactive oxygen species （ROS） and the expression of inducible nitric oxide synthase （iNOS） in rat isolated Kupffer cells （KCs） stimulated by Leptospira interrogans and Borrelia burgdorferi. METHODS： Rat Kupffer cells were separated by perfusion of the liver with 0.05% collagenase, and purified by Percoll gradients. Pudfied Kupffer cells were tested in vitro with alive L.interogans and B. burgdorferi preparations. The production of ROS was determined by chemiluminescence, whereas iNOS protein expression was evaluated by Western blot assay using anti-iNOS antibodies. RESULTS： B. burgdorferi and to a less extent L. interrogans induced ROS production with a peak 35 min after infection. The chemiluminescence signal progressively diminished and was undetectable by 180 min of incubation. Leptospirae and borreliae induced an increased iNOS expression in Kupffer cells that peaked at 6 hours and was still evident 22 h after infection. CONCLUSION： Both genera of spirochetes induced ROS and iNOS production in rat Kupffer cells. Since the cause of liver damage both in leptospiral as well as in borrelial infections are still unknown, we suggest that leptospira and borrelia damage of the liver can be initially mediated by oxygen radicals, and is then maintained at least in part by nitric oxide.
文摘Polymerase chain reaction (PCR) was used to detect the presence of Barrelia burgdoferi DNA in biological samples from patients with sarcoidosis. The target DNA sequence was of chromosomal origin. The amplified DNA sequence was analyzed by agarose gel electrophoresis, PAGE with silver staining, and the identity of amplified DNA was confirmed by restriction enzyme cleavage and DNA-DNA hybridization with a 32P-labelled probe. The assay was sensitive to fewer than two copies of B. burgdorferi genome, even in the presence of a 104-fold excess of human eukaryotic DNA , and was also specific to different B. burgdorferi strains tested. Sera serologically positive to B. burgdcrferi (n=26), bronchoalveolar lavage fluid and supernatant of BALF (n=26) and peripheral blood (n=9) from sarcoidosis patients were tested. The positive rate was low (4/26, 2/26. and 0/9, respectively). It was considered that DNA from B. burgdor ferimay be identified in a minority of patients with sarcoidosis, and it may play a pathogenetic role in such cases. More studies need to be done before advancing the hypothesis of an etiologic role of B. burgdorferi in sarcoidosis.
基金funded by the National Key Science and Technology Projects of China(2012ZX10004219 and 2013ZX10004001)
文摘A set of universal loop-mediated isothermal amplification （LAMP） primers targeting the flo gene was designed to detect Borrelia burgdorferi sensu lato （B. burgdorferi s.I.） in human samples. The sensitivity of LAMP was 20 copies/reaction, and the assay did not detect false positives among 11 other related bacteria. A positive LAMP result was obtained for 9 of the 24 confirmed cases and for 12 of 94 suspected cases. The positive rate of LAMP was the same as that of nested PCR. The LAMP is a useful diagnostic method that can be developed for rapid detection of B. burgdorferi s.I. in human sera. Combination of the LAMP and nested PCR was more sensitive for detecting B. burgdorferi s.I. in human serum samples.
文摘Objective:To investigate the precise species of tick vector and the Borrelia spirochete pathogen at the Heilongjiang Province international border with Russia.Methods:In dus study,ticks were collected from 12 Heilongjiang border crossings(including grasslands,shrublands,forests,and plantantions) to determine the rate and species type of spirochete-infected ticks and the most prevalent spirochete genotypes.Results:The ticks represented three genera and four species of the Ixodidae family[Ixodes persidcatus,Dermacentor silvarum,Haemapkysalis concinna and Haemaphysalis japonica].Ixodes persulcatus had the highest amount of Borrelia burgdorferi sensu lata infection of 25.6%and the most common species of Borrelia isolated from Ixodes persulcatus mas Borrelia garinii,strain PD91.Conclusions:Our results suggest that Borrelia garinii PD91- infected Ixodes persulcatus may be the principal cause of Lyme disease in the border crossing areas of Heilongjiang Province.
基金supported by Major Projects of the thirteenth Five Year Special for infectious diseases[2016ZX10004001-004 and 2018ZX10714002]。
文摘Objective To study the polymorphism in P66 and its human B-cell epitopes of Borrelia burgdorferi strains in China.Methods Polymerase chain reaction(PCR)and sequencing were used to obtain the P66 sequences of59 Chinese B.burgdorferi.Then the sequences were analyzed by MEGA 5.10 software and compared with the human B-cell epitope sequences from the Immune Epitope Database(IEDB)based on the reference strain of each genotype.Results Results showed that genetic and amino acid diversity presented in the 66 kD protein of all 59 Chinese strains,especially in Borrelia garinii(B.g)and Borrelia afzelii(B.a)strains.B.g strains were divided into three subclusters and two scattered strains JC1-7 and JC2-2 according to the amino acid sequences of P66.The P66 sequences of 15 Xinjiang strains represented by XI91-12 in the B.g subcluster1,changed from CAA to TAA codon at 508 aa position,resulting in early termination.Bases A and C were inserted at sequence position 1523 bp of strains FP1,LB20,LB21,and SZ21 in the B.a genotype,which resulted to early termination at position 511 aa.G base was inserted at 438 bp of LIP94-11 strain,which led to early termination at position 172 aa.Conclusion In P66 of 59 Chinese strains,polymorphisms were widely distributed.More importantly,the P66 amino acid sequences of B.g strains had a certain regional character.One of the characteristics of Xinjiang B.g isolates might be the variation at the 508 aa location in 15 Xinjiang B.g strains,which may be related to the strains’pathogenicity in this area.
文摘Worldwide, wild birds play a vital role in the dispersal of ticks that harbour tick-borne pathogens, including Borrelia burgdorferi, the Lyme disease bacterium. Using PCR testing, we found 124 (31%) of 405 ticks (4 species), which were collected from 21 species of birds in far-western Canada, to be infected with B. burgdorferi. Transstadial transmission of B. burgdorferi occurred from larva to nymph, plus nymph to adult, in the avian coastal tick, Ixodes auritulus, collected from songbirds in British Columbia (B.C). Collectively, all 3 motile life stages (larva, nymph, adult) of this tick had an infection prevalence of 31% for B. burgdorferi, which suggests vector competency. A Pacific Wren was highly infested with I. auritulus immatures, and 20 (44%) of 45 ticks (2 nymphs, 43 larvae) were infected with B. burgdorferi. This heavy infestation shows the high potential to initiate a new population of ticks and to disseminate Lyme spirochetes. Epidemiologically, B. burgdorferi-infected I. auritulus larvae collected from the Spotted Towhee, Swainson’s Thrush, Pacific Wren, and Fox Sparrow suggest that these avian hosts act as reservoirs for B. burgdorferi. In this study, the western blacklegged tick, Ixodes pacificus, and Ixodes spinipalpis played a limited role in the enzootic transmission cycle of B. burgdorferi along coastal B.C. We document the first record of I. spinipalpis on a bird in Alberta. Because songbirds widely disperse Lyme disease vector ticks, primary health providers and the general public must be vigilant that outdoors people may be bitten by B. burgdorferi-infected ticks throughout far-western Canada.
文摘There are several factors involved in the ability of Borrelia burgdorferi to retain a persistent infection within a mammalian host. These factors of immune evasion include regulation of membrane proteins, variable epitopes of surface proteins, protection against the immune system through tick saliva, the ability to migrate to regions where it is not exposed to the immune system or antibiotics, invagination or invasion within various cells, pleomorphic forms, and the potential to produce biofilms. The window of conventional treatment for Lyme disease is short and has the potential to display different symptoms depending on the strain of Borrelia bugdorferi. These symptoms are dependent on the localization of Borrelia burgdorferi which correlates to the significance of diagnosing Lyme disease early to prevent such a spread throughout the body. Such complications of Borrelia burgdorferi may demand new clinical treatment discoveries for patient fighting the chronic form.
文摘Chronic Lyme disease is predicated by an infection with Borrelia burgdorferi via tick vector. B. burgdorferi has been extensively researched with regard to its genome and cell biology. There are many unique characteristics to the bacteria itself;however, serological diagnostics and diagnosis based on symptoms can be complicated and potentially misleading. Other promising diagnostics were also evaluated in this review. Treatment of the chronic Lyme disease can be complicated and at times ineffective. The purpose of this review is to examine B. burgdorferi from a biological and clinical perspective.
文摘To investigate the correlation between sarcoidosis and Borrelia burgdorferi (Bb ) infection , flagella DNA of Bb were detected in 23 granulomatous tissue specimens from patients with confirmed sarcoidosis using polymerase chain reaction in siju technique (in situ PCR) and the antibodies to Bb were examined in 55 serum samples obtained from the patients by indirect immunoflurescence assays. Our data presented that:(1) None of granulomatous tissues was found to have Bb DNA in 23 tissue samples. (2) Thirty of 55 (54. 6% ) patients with sarcoidosis were found antibodies to Bb positive ,in contrast ,six of 60 (10%) normal subjects had antibodies against Bb ,the positive rate was remarkably higher in patient group than that in healthy group (P<0. 005) . The results suggest that Bb might not be the causative agent of sarcoidosis.the elevated titres of serum antibodies against Bb in patients with sarcoidosis is a nonspecific response.
文摘The sera of 180 human samples were tested for the presence of antibodies against Borrelia burgdorferi using the ELISA （enzyme-linked immunosorbent assay） technique. Out of 180 sero-samples, 46 （25.55%） were positive. Females of the age range 18-35 years had the highest rate of sero-positive samples 14 （38.88%）, while the highest percentage of sero-negative samples was found in males of the age range 50-80 years. The other sero-positive samples were： 6 （26.08%）, 6 （25%） and 3 （11.53%） in males of ages between 18-35, 35-50 and 50-80 years, respectively, and 11 （29.72%） and 6 （17.64%） in females in the age ranges 35-50 and 50-80 years, respectively. The mean concentration of Anti- B. burgdorferi antibody was higher （16.7 U/mL） when compared with mean concentration of normal value （5.5 U/mL）, P 〈 0.001.
文摘We document the first record of Borrelia americana in Canada. This Borrelia was detected in an avian coast tick, Ixodes auritulus (Acari: Ixodidae), collected from a Varied Thrush, Ixoreus naevius, along coastal British Columbia. Using real-time PCR and DNA sequencing of the flagellin gene, we determined that the borrelial amplicon from the I. auritulus nymph was 99% homologous with B. americana type strain SCW-41. Because patients infected with B. americana can be seronegative for Lyme disease, medical professionals should be willing to pursue molecular analyses and consider treatment for patients with Lyme disease-like symptoms.
文摘God has created many miraculous creature;ticks are one of them. Borrelia burgdorferi is a bacterium that lives into the gut of ticks. When such ticks feed upon the blood of Ticks and other livestock, bacteria are transferred into their blood stream of these hosts. A disease is caused into human beings if such infected tick bites humans that are called as Lyme disease. This review will help to have a keen study on the cause, sign, symptoms, prevention and management of this disease.
文摘To study the genetic characterization of four strains of Borrelia burgdorferi isolated in China. PCR technique was used to amplify the 5S-23S rRNA intergenic spacer DNA from the whole cellular DNA of isolated GXLD-4, 9, 18 and Chang 14, and then the amplified products were cloned into plasmid pGEM-T Easy and sequenced. It was found that the 5S-23S rRNA intergenic spacer DNA of the four isolates was 242?bp, revealing the nucleotide sequence identity of more than 99%. The four isolates had higher sequence identify with Borrelia valaisiana than with other genetic groups. These four isolates most likely belong to Borrelia valaisiana genomic group.
