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
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
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
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
Mucosa-associated lymphoid tissue (MALT) lymphoma generally occurs in the context of chronic inflammation or autoimmune disorders. The most common infections linked to MALT lymphomas include <em>Helicobacter pyl...Mucosa-associated lymphoid tissue (MALT) lymphoma generally occurs in the context of chronic inflammation or autoimmune disorders. The most common infections linked to MALT lymphomas include <em>Helicobacter pylori </em>(<em>Hp</em>)-associated gastritis, <em>Chlamydophila psittacii</em> and hepatitis C infection. Although <em>Borrelia burgdorferi </em>infection has been linked to primary cutaneous B-cell lymphoma (PCBCL), there is no known link between <em>Borrelia burgdorferi</em> infection and MALT lymphomas in the US. We report a patient who developed mucosa-associated lymphoid tissue (MALT) lymphoma of the colon in the context of untreated Lyme arthritis, and no other autoimmune disorders or infections known to be associated with MALT lymphoma. We recommend that Lyme disease due to <em>Borrelia burgdorferi</em> be considered as a possible underlying infection potentially contributing to the emergence of extranodal lymphoma.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
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
Lyme disease(LD),caused by Borrelia burgdorferi,is themost common vector-borne disease in the United States and Europe.Despite the standard 2–4 weeks'antibiotic treatment,approximately 10%–20%of patients will de...Lyme disease(LD),caused by Borrelia burgdorferi,is themost common vector-borne disease in the United States and Europe.Despite the standard 2–4 weeks'antibiotic treatment,approximately 10%–20%of patients will develop posttreatment LD syndrome,a condition that is poorly understood.One of the probable causes is thought to be the presence of B.burgdorferi persister forms that are not effectively killed by the current LD antibiotics.In this study,we evaluated nitroxoline,an antibiotic used to treat urinary tract infections,for its activity against a stationary-phase culture enriched with persister forms of B.burgdorferi.Nitroxoline was found to be more active than doxycycline and equally active as cefuroxime(standard LD antibiotics)against B.burgdorferi.Importantly,the nitroxoline two-drug combinations nitroxoline+cefuroxime and nitroxoline+clarithromycin,as well as the nitroxoline three-drug combination nitroxoline+cefuroxime+clarithromycin,were as effective as the persister drug daptomycin-based positive control three-drug combination cefuroxime+doxycycline+daptomycin,completely eradicating stationary-phase B.burgdorferi in the drug-exposure experiments and preventing regrowth in the subculture study.Future studies should evaluate these promising drug combinations in a persistent LD mouse model.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
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
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
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.
文摘Mucosa-associated lymphoid tissue (MALT) lymphoma generally occurs in the context of chronic inflammation or autoimmune disorders. The most common infections linked to MALT lymphomas include <em>Helicobacter pylori </em>(<em>Hp</em>)-associated gastritis, <em>Chlamydophila psittacii</em> and hepatitis C infection. Although <em>Borrelia burgdorferi </em>infection has been linked to primary cutaneous B-cell lymphoma (PCBCL), there is no known link between <em>Borrelia burgdorferi</em> infection and MALT lymphomas in the US. We report a patient who developed mucosa-associated lymphoid tissue (MALT) lymphoma of the colon in the context of untreated Lyme arthritis, and no other autoimmune disorders or infections known to be associated with MALT lymphoma. We recommend that Lyme disease due to <em>Borrelia burgdorferi</em> be considered as a possible underlying infection potentially contributing to the emergence of extranodal lymphoma.
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supported by the Global Lyme Alliance,the Steven and Alexandra Cohen Foundation,the LivLyme Foundation,NatCapLyme,and the Einstein-Sim Family Charitable Fund.
文摘Lyme disease(LD),caused by Borrelia burgdorferi,is themost common vector-borne disease in the United States and Europe.Despite the standard 2–4 weeks'antibiotic treatment,approximately 10%–20%of patients will develop posttreatment LD syndrome,a condition that is poorly understood.One of the probable causes is thought to be the presence of B.burgdorferi persister forms that are not effectively killed by the current LD antibiotics.In this study,we evaluated nitroxoline,an antibiotic used to treat urinary tract infections,for its activity against a stationary-phase culture enriched with persister forms of B.burgdorferi.Nitroxoline was found to be more active than doxycycline and equally active as cefuroxime(standard LD antibiotics)against B.burgdorferi.Importantly,the nitroxoline two-drug combinations nitroxoline+cefuroxime and nitroxoline+clarithromycin,as well as the nitroxoline three-drug combination nitroxoline+cefuroxime+clarithromycin,were as effective as the persister drug daptomycin-based positive control three-drug combination cefuroxime+doxycycline+daptomycin,completely eradicating stationary-phase B.burgdorferi in the drug-exposure experiments and preventing regrowth in the subculture study.Future studies should evaluate these promising drug combinations in a persistent LD mouse model.
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.