BACKGROUND Diffuse large B-cell lymphoma(DLBCL)is a common non-Hodgkin's lymphoma.R-CHOP is a protocol for long-term chemotherapy for DLBCL patients.Longterm chemotherapy can lead to low immunity and increase the ...BACKGROUND Diffuse large B-cell lymphoma(DLBCL)is a common non-Hodgkin's lymphoma.R-CHOP is a protocol for long-term chemotherapy for DLBCL patients.Longterm chemotherapy can lead to low immunity and increase the risk of opportunistic pathogen infections in immunocompromised patients.CASE SUMMARY We report a case of coinfection with Pneumocystis jirovecii(P.jirovecii)and Legionella pneumophila(L.pneumophila)in a patient with DLBCL.The patient was a 40-year-old female who was diagnosed with DLBCL and was admitted due to pulmonary infection.P.jirovecii and L.pneumophila were detected in her bronchoalveolar lavage fluid by hexamine silver staining,isothermal amplification and metagenomic sequencing.CONCLUSION To the best of our knowledge,this is the first case of P.jirovecii and L.pneumophila coinfection found in a DLBCL patient.Clinicians should be aware of the risk of complicated infection in patients undergoing long-term chemotherapy.展开更多
Legionella pneumophila infection can cause Legionnaires’disease,a severe form of pneumonia.Extrapulmonary manifestations of Legionella infections include myocarditis,pericarditis,and endocarditis.We present a rare ca...Legionella pneumophila infection can cause Legionnaires’disease,a severe form of pneumonia.Extrapulmonary manifestations of Legionella infections include myocarditis,pericarditis,and endocarditis.We present a rare case of pneumonia caused by Legionella pneumophila with a possible etiologic link to a recently recovered culture-negative infective endocarditis.展开更多
Objective:To investigate the prevalence,isolation,identification,characterization,antibiotic profile and pathogenicity of Legionellae isolated from various set of waters.Methods:A total of 400 water samples were colle...Objective:To investigate the prevalence,isolation,identification,characterization,antibiotic profile and pathogenicity of Legionellae isolated from various set of waters.Methods:A total of 400 water samples were collected from different water sources.Water samples were pretreated using acid treatment followed by concentration and culture on buffered charcoal yeast extract agar.Parameters like ability of Legionella isolates to grow in various p H range,effect of different concentrations of chlorine and effect of different temperature optima were set up.Biochemical tests were performed to separate Legionellae into species.Antibiotic sensitivity tests and test for pathogenicity were also conducted on isolated strains.Results:The rates of isolation of Legionella pneumophila(L.pneumophila) in different water sources were found to be 20%(lakes),10%(ponds),8%(water-tanks) and 1%(rivers).Most of the isolates could grow in variable p H 6–8 and it could also survive the normal level of chlorination and even at temperature of 42 C.Isolated species of Legionellae resulted in identification of 5 different species,L.pneumophila being the dominant one.Strains of L.pneumophila were resistant to many antibiotics.Inoculation of Legionellae into intracerebral route of suckling mice revealed that L.pneumophila was the most virulent.Conclusions:Serious and fatal L.pneumophila infections may be transmitted through water.Legionella can survive under various conditions in various water sources.L.pneumophila is the important pathogen causing human disease.Great challenge prevails to health care professionals because these Legionellae acquired antibiotic resistance to many routinely prescribed antibiotics.展开更多
Legionellae are found in freshwater environments or wet soil, but the major reservoirs are man-made aquatic environments, particularly warm water systems. Our aim was to study the occurrence of Legionella contaminatio...Legionellae are found in freshwater environments or wet soil, but the major reservoirs are man-made aquatic environments, particularly warm water systems. Our aim was to study the occurrence of Legionella contamination in hot potable water supply systems in apartment and public buildings. Correlations between Legionella spp. positive cases and water source, sampling point and temperature of hot water at the point of consumption were studied. A total of 149 hot water samples were collected in 16 cities and districts of Latvia. Only Legionella pneumophila was isolated. L. pneumophila was found in 63 out of 149 （42%） hot water samples. From all Legionella spp. positive samples, 17% represented L. pneumophila serogroup 1 and 78% L. pneumophila serogroups 2-14 （15）. In 5% of Legionella spp. positive samples, both serogroups 1 and 2-14（15） were isolated. Statistically significant differences were observed in the distribution of L. pneumophila serogroup 1 in samples from various water sources. L. pneumophila was found in 45% of samples from private apartments and in 27% of samples from public buildings. Data analysis confirmed that the temperature of hot water significantly affects the frequency of L. pneumophila positive cases （p 〈 0.05）. Data showed that 85% of consumers received hot water at a temperature below 50°C.展开更多
BACKGROUND Legionella pneumophila(L.pneumophila)is a gram-negative intracellular bacillus composed of sixteen different serogroups.It is mostly known to cause pneumonia in individuals with known risk factors as immuno...BACKGROUND Legionella pneumophila(L.pneumophila)is a gram-negative intracellular bacillus composed of sixteen different serogroups.It is mostly known to cause pneumonia in individuals with known risk factors as immunocompromised status,tobacco use,chronic organ failure or age older than 50 years.Although parapneumonic pleural effusion is frequent in legionellosis,pleural empyema is very uncommon.In this study,we report a case of fatal pleural empyema caused by L.pneumophila serogroup 1 in an 81-year-old man with multiple risk factors.CASE SUMMARY An 81-year-old man presented to the emergency with a 3 wk dyspnea,fever and left chest pain.His previous medical conditions were chronic lymphocytic leukemia,diabetes mellitus,chronic kidney failure,hypertension and hyperlipidemia,without tobacco use.Chest X-ray and comouted tomographyscan confirmed a large left pleural effusion,which puncture showed a citrine exudate with negative standard bacterial cultures.Despite intravenous cefotaxime antibiotherapy,patient’s worsening condition after 10 d led to thoracocentesis and evacuation of 2 liters of pus.The patient progressively developed severe hypoxemia and multiorgan failure occurred.The patient was treated by antibiotherapy with cefepime and amikacin and with adequate symptomatic shock treatment,but died of uncontrolled sepsis.The next day,cultures of the surgical pleural liquid samples yielded L.pneumophila serogroup 1,consistent with the diagnosis of pleural legionellosis.CONCLUSION L.pneumophila should be considered in patients with multiple risk factors and undiagnosed pleural empyema unresponsive to conventional antibiotherapy.展开更多
Legionella pneumophila is a Gram-negative bacterium ubiquitously present in freshwater environments and causes a serious type of pneumonia called Legionnaires’disease.During infections,L.pneumophila releases over 300...Legionella pneumophila is a Gram-negative bacterium ubiquitously present in freshwater environments and causes a serious type of pneumonia called Legionnaires’disease.During infections,L.pneumophila releases over 300 effector proteins into host cells through an Icm/Dot type IV secretion system to manipulate the host defense system for survival within the host.Notably,certain effector proteins mediate posttranslational modifications(PTMs),serving as useful approaches exploited by L.pneumophila to modify host proteins.Some effectors catalyze the addition of host protein PTMs,while others mediate the removal of PTMs from host proteins.In this review,we summarize L.pneumophila effector-mediated PTMs of host proteins,including phosphorylation,ubiquitination,glycosylation,AMPylation,phosphocholination,methylation,and ADP-ribosylation,as well as dephosphorylation,deubiquitination,deAMPylation,deADP-ribosylation,dephosphocholination,and delipidation.We describe their molecular mechanisms and biological functions in the regulation of bacterial growth and Legionella-containing vacuole biosynthesis and in the disruption of host immune and defense machinery.展开更多
Objective:To investigate the presence of Legionella pneumophila(L.pneumophila)in domestic water in Bitlis province and to determine the in vitro susceptibility of the isolates against several antibiotics.Methods:A tot...Objective:To investigate the presence of Legionella pneumophila(L.pneumophila)in domestic water in Bitlis province and to determine the in vitro susceptibility of the isolates against several antibiotics.Methods:A total of 320 tap water samples were collected from the urban areas and villages of Bitlis province during the period from May to December 2010.All samples were cultured on plates of buffered charcoal yeast extract agar.L.pneumophila strains were tested for antimicrobial susceptibility by the disk diffusion method.Results:L.pneumophila strains were isolated from six(1.9%)domestic water samples.All isolates were typed as L.pneumophila serogroup 1 by latex agglutination test.Four of strains were isolated in July and two of them were detected in August.Antibiotic susceptibility testing was carried out on six L.pneumophila serogroup 1 isolates.Of the six strains,two was resistant to erythromycin and streptomycin,four were resistant to ampicillin and gentamicin,but all were sensitive to chloramphenicol and doxycycline.Conclusions:Our results indicate that L.pneumophila serogroup 1 is the most common type in the domestic water samples and threats public health.This is the first report of L.pneumophila in domestic water samples from Bitlis province.展开更多
<i>Legionella pneumophila</i> (<i>L. pneumophila</i>) is the most common causative agents for all outbreaks of Legionnaires’ disease. Prevention and control of Legionellosis requires surveying...<i>Legionella pneumophila</i> (<i>L. pneumophila</i>) is the most common causative agents for all outbreaks of Legionnaires’ disease. Prevention and control of Legionellosis requires surveying and monitoring of <i>Legionella</i> in the environment using conventional and modern technologies. The present study aims to compare detection of <i>L. pneumophila</i> in water samples using both culture and PCR techniques. A pre-enriched contaminated water sample was split into 13 subsamples. Culture and PCR tests were done from the subsamples after different intervals. The results showed a positive PCR result for <i>L. pneumophila</i> after 8 h of incubation. Also, <i>L. pneumophila</i> was detected by culture on non-selective BCYNE agar and selective GPVC agar after 5 and 6 days of incubation respectively. There was no significant difference between the non-selective BCYE- and the selective GVPC method. The PCR procedure was found more sensitive and differed significantly from the conventional selective GVPC method in isolation of <i>L. pneumophila</i> from water samples. It was concluded that pre-enrichment incubation allows the detection of <i>L. pneumophila</i> by PCR within a maximum of 12 h from the collection of water samples.展开更多
Objective To establish Surface-enhanced Raman Spectroscopy（SERS） can be used as a rapid and reliable method to distinguish virulent strain and mild strain of L. pneumophila. Methods We isolated and characterized of ...Objective To establish Surface-enhanced Raman Spectroscopy（SERS） can be used as a rapid and reliable method to distinguish virulent strain and mild strain of L. pneumophila. Methods We isolated and characterized of bacterial strains from ATCC and water samples strains, while we analyzed data from SERS technology using gold nanoparticles as a base and cell infections were employed to rapidly detect L. pneumophila strains. Origin 8.0 was used to collect Raman spectra, smooth and homogenize data, and to contrast spectra. Principal component analysis（PCA） was conducted to discriminate differences between groups using the multivariate analysis package Py Chem 3.0.5. Results Our results indicated that the peaks of high virulence strains reached ≥4000. This criterion was verified by subsequent cell experiments. In addition, we also conducted SERS rapid identification on the virulence of several collected clinical strains and obtained accurate results. Conclusion The present study indicates that the established SERS protocol can be used as a rapid and reliable method to distinguish virulent and mildly virulent strains of L. pneumophila, which can be further used in clinical samples.展开更多
污水中普遍存在大量病原菌,污水处理厂作为接收和处理污水的主要场所,在控制病原菌污染和保障再生水安全中发挥重要作用。研究利用16S r RNA测序技术和实时荧光定量PCR技术对中国北方一座污水处理厂夏、冬两季的细菌群落结构和病原细菌...污水中普遍存在大量病原菌,污水处理厂作为接收和处理污水的主要场所,在控制病原菌污染和保障再生水安全中发挥重要作用。研究利用16S r RNA测序技术和实时荧光定量PCR技术对中国北方一座污水处理厂夏、冬两季的细菌群落结构和病原细菌存在情况进行分析。研究结果表明,共检出27个病原菌菌属,其中假单胞菌属(Pseudomonas)、不动杆菌属(Acinetobacter)是主要病原菌属。经过一系列工艺处理,出水中含有病原菌属数目和含量明显降低,但发现常规出水检测指标大肠杆菌不能指示其他病原菌的存在情况和风险水平,提示仍需引入新的检测指标减少再生水回用的病原菌风险。展开更多
In this study the authors compared the sequence types （STs） designed by sequence based typing （SBT） of 4 clinical and 12 environmental strains of Legionella pneumophila serogroup 1 （LP1） which were isolated from...In this study the authors compared the sequence types （STs） designed by sequence based typing （SBT） of 4 clinical and 12 environmental strains of Legionella pneumophila serogroup 1 （LP1） which were isolated from hospital facilities for the mentally disabled. The strains were selected after a retrospective surveillance of 565 clinical records （2002-2009） and investigations of water circuit. It was possible to correlate two clinical strains with the corresponding environment, which were collected from showers that had exposed the patients （ST685, ST16） and two clinical strains present in the same structure （STI）. The other environmental strains were isolated from water in the department with confirmed or suspected clinical cases. All the strains （seven） from the first structure had ST188; two from the second structure had ST34; and the last from the third structure, gave an ST694. The results were compared with the European Working Group for Legionella Infections （EWGLI） database： the ST 1, 16, 34 and 188 were already known in literature, among clinical and nosocomial cases, especially for ST 1, the most distributed worldwide. Two STs were new to the database. ST685 was isolated both from a patient and from the water; ST694, which was found exclusively in the environmental compartment of a control structure （no cases of legionellosis and low number of nosocomial pneumonia）, was unknown in the literature and the authors could only speculate on its possible minor virulence and/or distribution. The implementation of SBT and international comparisons may be useful to gain genotypic knowledge of circulating environmental strains, also verifying their presence in the clinical setting.展开更多
We present the case of a 42-year-old man affected by psoriasis with Staphylococcus Haemolyticus superin-fection of Legionella pneumonia during infliximab therapy. The introduction of compounds that block TNF-α has yi...We present the case of a 42-year-old man affected by psoriasis with Staphylococcus Haemolyticus superin-fection of Legionella pneumonia during infliximab therapy. The introduction of compounds that block TNF-α has yielded great benefits for patients affected by selected autoimmune diseases that fail to respond to classic anti-inflammatory agents, but, on the other hand, has led to an increased susceptibility to infec-tions, in particular of those caused by intracellular pathogens, such as L. Pneumophila. Emerging evi-dence suggests that legionellosis can be complicated by superinfection with other agents, including sap-rophytic microorganisms, among which coagulase- negative staphylococci. To our knowledge, this is the first report of systemic legionellosis with superinfec-tion by S. Haemolyticus, an emerging nosocomial multi-resistant pathogen that commonly causes sep-ticemia, osteomyelitis or endocarditis, but has not so far been associated with necrotizing pneumonia. De-spite the optimal antimicrobial therapy for Staphylo-coccus spp. pneumonia is still controversial, evidence suggests that in patients with confirmed positivity for methicillin resistant strains, particularly if sensitivity to vancomycin is suboptimal, linezolid should be the first choice therapy, being superior to vancomycin and teicoplanin.展开更多
目的观察组蛋白去乙酰化酶6(HDAC6)调控嗜肺军团菌鞭毛重组蛋白A(rflaA)对小鼠巨噬细胞自噬相关因子表达的影响,分析其可能的作用机制。方法采用支气管肺泡灌洗法提取C57BL/6J与HDAC6-/-C57BL/6J两种小鼠巨噬细胞,用小鼠巨噬细胞表面标...目的观察组蛋白去乙酰化酶6(HDAC6)调控嗜肺军团菌鞭毛重组蛋白A(rflaA)对小鼠巨噬细胞自噬相关因子表达的影响,分析其可能的作用机制。方法采用支气管肺泡灌洗法提取C57BL/6J与HDAC6-/-C57BL/6J两种小鼠巨噬细胞,用小鼠巨噬细胞表面标记物F4/80鉴定;纯化rflaA,CCK-8法检测其对小鼠巨噬细胞半数抑制浓度(IC50),筛选最佳作用浓度用于后续实验;rflaA分别干预C57BL/6J及HDAC6-/-C57BL/6J小鼠巨噬细胞6、12和24 h,RT-qPCR、Western blot及免疫荧光检测各组自噬相关因子自噬效应蛋白1(Beclin1)、自噬相关蛋白5(ATG5)、自噬微管相关蛋白轻链3(LC3)、SQSTM1蛋白(P62)的表达水平。结果根据CCK-8结果计算,IC50为0.41μg·μL^(-1),最佳作用浓度为0.041μg·μL^(-1)用于后续实验;RT-qPCR、Western blot、免疫荧光结果显示,rflaA干预C57BL/6J小鼠巨噬细胞后,与0 h相比,6、12、24 h HDAC6的表达水平升高,LC3、ATG5表达水平均降低,P62的表达水平升高,Beclin1的表达水平先降低后升高(P均<0.05);rflaA干预HDAC6-/-C57BL/6J小鼠巨噬细胞后,与0 h相比,6、12、24 h LC3、ATG5、Beclin1表达水平均升高,P62的表达水平降低(P均<0.05);在相同的时间点,与C57BL/6J小鼠巨噬细胞各组相比,HDAC6敲除后各组细胞ATG5、LC3表达水平升高,Beclin1先升高后降低,P62降低(P均<0.05)。结论HDAC6促进rflaA抑制小鼠巨噬细胞自噬,HDAC6可能通过影响微管蛋白乙酰化干扰巨噬细胞自噬。展开更多
文摘BACKGROUND Diffuse large B-cell lymphoma(DLBCL)is a common non-Hodgkin's lymphoma.R-CHOP is a protocol for long-term chemotherapy for DLBCL patients.Longterm chemotherapy can lead to low immunity and increase the risk of opportunistic pathogen infections in immunocompromised patients.CASE SUMMARY We report a case of coinfection with Pneumocystis jirovecii(P.jirovecii)and Legionella pneumophila(L.pneumophila)in a patient with DLBCL.The patient was a 40-year-old female who was diagnosed with DLBCL and was admitted due to pulmonary infection.P.jirovecii and L.pneumophila were detected in her bronchoalveolar lavage fluid by hexamine silver staining,isothermal amplification and metagenomic sequencing.CONCLUSION To the best of our knowledge,this is the first case of P.jirovecii and L.pneumophila coinfection found in a DLBCL patient.Clinicians should be aware of the risk of complicated infection in patients undergoing long-term chemotherapy.
文摘Legionella pneumophila infection can cause Legionnaires’disease,a severe form of pneumonia.Extrapulmonary manifestations of Legionella infections include myocarditis,pericarditis,and endocarditis.We present a rare case of pneumonia caused by Legionella pneumophila with a possible etiologic link to a recently recovered culture-negative infective endocarditis.
基金Supported by Rockefeller Foundation,USA(Grant No.External-R.F-2396725281-2015-16)
文摘Objective:To investigate the prevalence,isolation,identification,characterization,antibiotic profile and pathogenicity of Legionellae isolated from various set of waters.Methods:A total of 400 water samples were collected from different water sources.Water samples were pretreated using acid treatment followed by concentration and culture on buffered charcoal yeast extract agar.Parameters like ability of Legionella isolates to grow in various p H range,effect of different concentrations of chlorine and effect of different temperature optima were set up.Biochemical tests were performed to separate Legionellae into species.Antibiotic sensitivity tests and test for pathogenicity were also conducted on isolated strains.Results:The rates of isolation of Legionella pneumophila(L.pneumophila) in different water sources were found to be 20%(lakes),10%(ponds),8%(water-tanks) and 1%(rivers).Most of the isolates could grow in variable p H 6–8 and it could also survive the normal level of chlorination and even at temperature of 42 C.Isolated species of Legionellae resulted in identification of 5 different species,L.pneumophila being the dominant one.Strains of L.pneumophila were resistant to many antibiotics.Inoculation of Legionellae into intracerebral route of suckling mice revealed that L.pneumophila was the most virulent.Conclusions:Serious and fatal L.pneumophila infections may be transmitted through water.Legionella can survive under various conditions in various water sources.L.pneumophila is the important pathogen causing human disease.Great challenge prevails to health care professionals because these Legionellae acquired antibiotic resistance to many routinely prescribed antibiotics.
文摘Legionellae are found in freshwater environments or wet soil, but the major reservoirs are man-made aquatic environments, particularly warm water systems. Our aim was to study the occurrence of Legionella contamination in hot potable water supply systems in apartment and public buildings. Correlations between Legionella spp. positive cases and water source, sampling point and temperature of hot water at the point of consumption were studied. A total of 149 hot water samples were collected in 16 cities and districts of Latvia. Only Legionella pneumophila was isolated. L. pneumophila was found in 63 out of 149 （42%） hot water samples. From all Legionella spp. positive samples, 17% represented L. pneumophila serogroup 1 and 78% L. pneumophila serogroups 2-14 （15）. In 5% of Legionella spp. positive samples, both serogroups 1 and 2-14（15） were isolated. Statistically significant differences were observed in the distribution of L. pneumophila serogroup 1 in samples from various water sources. L. pneumophila was found in 45% of samples from private apartments and in 27% of samples from public buildings. Data analysis confirmed that the temperature of hot water significantly affects the frequency of L. pneumophila positive cases （p 〈 0.05）. Data showed that 85% of consumers received hot water at a temperature below 50°C.
文摘BACKGROUND Legionella pneumophila(L.pneumophila)is a gram-negative intracellular bacillus composed of sixteen different serogroups.It is mostly known to cause pneumonia in individuals with known risk factors as immunocompromised status,tobacco use,chronic organ failure or age older than 50 years.Although parapneumonic pleural effusion is frequent in legionellosis,pleural empyema is very uncommon.In this study,we report a case of fatal pleural empyema caused by L.pneumophila serogroup 1 in an 81-year-old man with multiple risk factors.CASE SUMMARY An 81-year-old man presented to the emergency with a 3 wk dyspnea,fever and left chest pain.His previous medical conditions were chronic lymphocytic leukemia,diabetes mellitus,chronic kidney failure,hypertension and hyperlipidemia,without tobacco use.Chest X-ray and comouted tomographyscan confirmed a large left pleural effusion,which puncture showed a citrine exudate with negative standard bacterial cultures.Despite intravenous cefotaxime antibiotherapy,patient’s worsening condition after 10 d led to thoracocentesis and evacuation of 2 liters of pus.The patient progressively developed severe hypoxemia and multiorgan failure occurred.The patient was treated by antibiotherapy with cefepime and amikacin and with adequate symptomatic shock treatment,but died of uncontrolled sepsis.The next day,cultures of the surgical pleural liquid samples yielded L.pneumophila serogroup 1,consistent with the diagnosis of pleural legionellosis.CONCLUSION L.pneumophila should be considered in patients with multiple risk factors and undiagnosed pleural empyema unresponsive to conventional antibiotherapy.
基金funded by the National Natural Science Foundation of China(32170185,22011530161,31801166,and 91854101)the Natural Science Foundation of Chongqing,China(cstc2021jcyj-msxmX0030 and CSTB2022NSCQ-MSX0463)+2 种基金the Venture Innovation Support Program for Chongqing Overseas Returnees(cx2022066)the Fundamental Research Funds for the Central Universities(2022CDJYGRH-002)the National Training Program of Innovation and Entrepreneurship for Undergraduates(202210611088).
文摘Legionella pneumophila is a Gram-negative bacterium ubiquitously present in freshwater environments and causes a serious type of pneumonia called Legionnaires’disease.During infections,L.pneumophila releases over 300 effector proteins into host cells through an Icm/Dot type IV secretion system to manipulate the host defense system for survival within the host.Notably,certain effector proteins mediate posttranslational modifications(PTMs),serving as useful approaches exploited by L.pneumophila to modify host proteins.Some effectors catalyze the addition of host protein PTMs,while others mediate the removal of PTMs from host proteins.In this review,we summarize L.pneumophila effector-mediated PTMs of host proteins,including phosphorylation,ubiquitination,glycosylation,AMPylation,phosphocholination,methylation,and ADP-ribosylation,as well as dephosphorylation,deubiquitination,deAMPylation,deADP-ribosylation,dephosphocholination,and delipidation.We describe their molecular mechanisms and biological functions in the regulation of bacterial growth and Legionella-containing vacuole biosynthesis and in the disruption of host immune and defense machinery.
文摘Objective:To investigate the presence of Legionella pneumophila(L.pneumophila)in domestic water in Bitlis province and to determine the in vitro susceptibility of the isolates against several antibiotics.Methods:A total of 320 tap water samples were collected from the urban areas and villages of Bitlis province during the period from May to December 2010.All samples were cultured on plates of buffered charcoal yeast extract agar.L.pneumophila strains were tested for antimicrobial susceptibility by the disk diffusion method.Results:L.pneumophila strains were isolated from six(1.9%)domestic water samples.All isolates were typed as L.pneumophila serogroup 1 by latex agglutination test.Four of strains were isolated in July and two of them were detected in August.Antibiotic susceptibility testing was carried out on six L.pneumophila serogroup 1 isolates.Of the six strains,two was resistant to erythromycin and streptomycin,four were resistant to ampicillin and gentamicin,but all were sensitive to chloramphenicol and doxycycline.Conclusions:Our results indicate that L.pneumophila serogroup 1 is the most common type in the domestic water samples and threats public health.This is the first report of L.pneumophila in domestic water samples from Bitlis province.
文摘<i>Legionella pneumophila</i> (<i>L. pneumophila</i>) is the most common causative agents for all outbreaks of Legionnaires’ disease. Prevention and control of Legionellosis requires surveying and monitoring of <i>Legionella</i> in the environment using conventional and modern technologies. The present study aims to compare detection of <i>L. pneumophila</i> in water samples using both culture and PCR techniques. A pre-enriched contaminated water sample was split into 13 subsamples. Culture and PCR tests were done from the subsamples after different intervals. The results showed a positive PCR result for <i>L. pneumophila</i> after 8 h of incubation. Also, <i>L. pneumophila</i> was detected by culture on non-selective BCYNE agar and selective GPVC agar after 5 and 6 days of incubation respectively. There was no significant difference between the non-selective BCYE- and the selective GVPC method. The PCR procedure was found more sensitive and differed significantly from the conventional selective GVPC method in isolation of <i>L. pneumophila</i> from water samples. It was concluded that pre-enrichment incubation allows the detection of <i>L. pneumophila</i> by PCR within a maximum of 12 h from the collection of water samples.
基金supported by National Key Technologies Research and Development Program of China(2013ZX10004-610)China Ministry of Science and Technology(MOST)Project 973(2012CB955501)WL is a principal investigator of the NSFC Innovative Research Group(Grant No.81321063)
文摘Objective To establish Surface-enhanced Raman Spectroscopy（SERS） can be used as a rapid and reliable method to distinguish virulent strain and mild strain of L. pneumophila. Methods We isolated and characterized of bacterial strains from ATCC and water samples strains, while we analyzed data from SERS technology using gold nanoparticles as a base and cell infections were employed to rapidly detect L. pneumophila strains. Origin 8.0 was used to collect Raman spectra, smooth and homogenize data, and to contrast spectra. Principal component analysis（PCA） was conducted to discriminate differences between groups using the multivariate analysis package Py Chem 3.0.5. Results Our results indicated that the peaks of high virulence strains reached ≥4000. This criterion was verified by subsequent cell experiments. In addition, we also conducted SERS rapid identification on the virulence of several collected clinical strains and obtained accurate results. Conclusion The present study indicates that the established SERS protocol can be used as a rapid and reliable method to distinguish virulent and mildly virulent strains of L. pneumophila, which can be further used in clinical samples.
文摘污水中普遍存在大量病原菌,污水处理厂作为接收和处理污水的主要场所,在控制病原菌污染和保障再生水安全中发挥重要作用。研究利用16S r RNA测序技术和实时荧光定量PCR技术对中国北方一座污水处理厂夏、冬两季的细菌群落结构和病原细菌存在情况进行分析。研究结果表明,共检出27个病原菌菌属,其中假单胞菌属(Pseudomonas)、不动杆菌属(Acinetobacter)是主要病原菌属。经过一系列工艺处理,出水中含有病原菌属数目和含量明显降低,但发现常规出水检测指标大肠杆菌不能指示其他病原菌的存在情况和风险水平,提示仍需引入新的检测指标减少再生水回用的病原菌风险。
文摘In this study the authors compared the sequence types （STs） designed by sequence based typing （SBT） of 4 clinical and 12 environmental strains of Legionella pneumophila serogroup 1 （LP1） which were isolated from hospital facilities for the mentally disabled. The strains were selected after a retrospective surveillance of 565 clinical records （2002-2009） and investigations of water circuit. It was possible to correlate two clinical strains with the corresponding environment, which were collected from showers that had exposed the patients （ST685, ST16） and two clinical strains present in the same structure （STI）. The other environmental strains were isolated from water in the department with confirmed or suspected clinical cases. All the strains （seven） from the first structure had ST188; two from the second structure had ST34; and the last from the third structure, gave an ST694. The results were compared with the European Working Group for Legionella Infections （EWGLI） database： the ST 1, 16, 34 and 188 were already known in literature, among clinical and nosocomial cases, especially for ST 1, the most distributed worldwide. Two STs were new to the database. ST685 was isolated both from a patient and from the water; ST694, which was found exclusively in the environmental compartment of a control structure （no cases of legionellosis and low number of nosocomial pneumonia）, was unknown in the literature and the authors could only speculate on its possible minor virulence and/or distribution. The implementation of SBT and international comparisons may be useful to gain genotypic knowledge of circulating environmental strains, also verifying their presence in the clinical setting.
文摘We present the case of a 42-year-old man affected by psoriasis with Staphylococcus Haemolyticus superin-fection of Legionella pneumonia during infliximab therapy. The introduction of compounds that block TNF-α has yielded great benefits for patients affected by selected autoimmune diseases that fail to respond to classic anti-inflammatory agents, but, on the other hand, has led to an increased susceptibility to infec-tions, in particular of those caused by intracellular pathogens, such as L. Pneumophila. Emerging evi-dence suggests that legionellosis can be complicated by superinfection with other agents, including sap-rophytic microorganisms, among which coagulase- negative staphylococci. To our knowledge, this is the first report of systemic legionellosis with superinfec-tion by S. Haemolyticus, an emerging nosocomial multi-resistant pathogen that commonly causes sep-ticemia, osteomyelitis or endocarditis, but has not so far been associated with necrotizing pneumonia. De-spite the optimal antimicrobial therapy for Staphylo-coccus spp. pneumonia is still controversial, evidence suggests that in patients with confirmed positivity for methicillin resistant strains, particularly if sensitivity to vancomycin is suboptimal, linezolid should be the first choice therapy, being superior to vancomycin and teicoplanin.
文摘目的观察组蛋白去乙酰化酶6(HDAC6)调控嗜肺军团菌鞭毛重组蛋白A(rflaA)对小鼠巨噬细胞自噬相关因子表达的影响,分析其可能的作用机制。方法采用支气管肺泡灌洗法提取C57BL/6J与HDAC6-/-C57BL/6J两种小鼠巨噬细胞,用小鼠巨噬细胞表面标记物F4/80鉴定;纯化rflaA,CCK-8法检测其对小鼠巨噬细胞半数抑制浓度(IC50),筛选最佳作用浓度用于后续实验;rflaA分别干预C57BL/6J及HDAC6-/-C57BL/6J小鼠巨噬细胞6、12和24 h,RT-qPCR、Western blot及免疫荧光检测各组自噬相关因子自噬效应蛋白1(Beclin1)、自噬相关蛋白5(ATG5)、自噬微管相关蛋白轻链3(LC3)、SQSTM1蛋白(P62)的表达水平。结果根据CCK-8结果计算,IC50为0.41μg·μL^(-1),最佳作用浓度为0.041μg·μL^(-1)用于后续实验;RT-qPCR、Western blot、免疫荧光结果显示,rflaA干预C57BL/6J小鼠巨噬细胞后,与0 h相比,6、12、24 h HDAC6的表达水平升高,LC3、ATG5表达水平均降低,P62的表达水平升高,Beclin1的表达水平先降低后升高(P均<0.05);rflaA干预HDAC6-/-C57BL/6J小鼠巨噬细胞后,与0 h相比,6、12、24 h LC3、ATG5、Beclin1表达水平均升高,P62的表达水平降低(P均<0.05);在相同的时间点,与C57BL/6J小鼠巨噬细胞各组相比,HDAC6敲除后各组细胞ATG5、LC3表达水平升高,Beclin1先升高后降低,P62降低(P均<0.05)。结论HDAC6促进rflaA抑制小鼠巨噬细胞自噬,HDAC6可能通过影响微管蛋白乙酰化干扰巨噬细胞自噬。
