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F Poumarat - One of the best experts on this subject based on the ideXlab platform.
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Comparison of isolates of Mycoplasma mycoides subspecies capri from asymptomatic and septicaemic goats.
Journal of Comparative Pathology, 2010Co-Authors: Florence Tardy, F Poumarat, Albert Tricot, Laure Maigre, L. Nguyen, D. Le GrandAbstract:Summary Strains of Mycoplasma mycoides subspecies capri ( Mmc ) are frequently isolated from goats with contagious agalactia, but they can also be recovered from herds that have shown no clinical signs of Mycoplasmosis for several years. The present study was conducted in order to explore the potential genetic and antigenic differences existing between an Mmc strain isolated from an outbreak (septicaemic) and a strain isolated from the ear canal of a goat belonging to a herd with no recent episode of Mycoplasmosis (carriage strain). The genomes of the two strains, compared by suppression subtractive hybridization, were shown to be poorly divergent. The two strains were inoculated into goats to produce specific antisera, but both induced fatal Mycoplasmosis. These results indicate that septicaemic and carriage strains cannot be distinguished by their genetic background or by their pathogenic capacity under experimental conditions.
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Mycoplasmoses of ruminants in France: recent data from the national surveillance network
BMC Veterinary Research, 2010Co-Authors: Myriam Chazel, Dominique Le Grand, Florence Tardy, Didier Calavas, F PoumaratAbstract:Background Ruminant mycoplasmoses are important diseases worldwide and several are listed by the World Organization for Animal Health to be of major economic significance. In France the distribution of mycoplasmal species isolated from clinical samples collected from diseased animals upon veterinary request, is monitored by a network known as VIGIMYC (for VIGIlance to MYCoplasmoses of ruminants). The veterinary diagnostic laboratories collaborating with VIGIMYC are responsible for isolating the mycoplasmas while identification of the isolates is centralized by the French Food Safety Agency (AFSSA) in Lyon. The VIGIMYC framework can also be used for specific surveys and one example, on the prevalence of M. bovis in bovine respiratory diseases, is presented here. Results Between 2003 and 2008, 34 laboratories were involved in the network and 1904 mycoplasma isolates, originating from the main ruminant-breeding areas, were identified. For cattle, the high prevalence of M. bovis in bronchopneumonia, notably in young animals, was confirmed by VIGIMYC and an associated specific survey, whereas the non-emergence of species such as M. alkalescens and M. canis was also demonstrated. The etiological agent of bovine contagious pleuropneumonia was never isolated. The principal Mycoplasmosis in goats was contagious agalactia with M. mycoides subsp. capri as main agent. Ovine mycoplasmoses, most of which were associated with pneumonia in lambs, were infrequently reported. One exception was ovine contagious agalactia (due to M. agalactiae ) that has recently re-emerged in the Pyrénées where it had been endemic for years and was also reported in Corsica, which was previously considered free. Conclusions Although VIGIMYC is a passive network and somewhat biased as regards sample collection and processing, it has provided, in this study, an overview of the main mycoplasmoses of ruminants in France. The French epidemiological situation is compared to those existing elsewhere in the world.
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mycoplasma mycoides subsp mycoides biotype large colony isolates from healthy and diseased goats prevalence and typing
Veterinary Microbiology, 2007Co-Authors: Florence Tardy, Pascale Mercier, Michel Solsona, E Saras, F PoumaratAbstract:Most severe goat Mycoplasmosis outbreaks in France are caused by Mycoplasma mycoides subsp. mycoides biotype LC (MmmLC). However, MmmLC can also be recovered from ear canals of healthy goats or from bulk milk collected in herds showing no clinical signs of Mycoplasmosis. To improve our understanding of how MmmLC strains are balanced between pathogenic ones and asymptomatically carried ones, descriptive epidemiological data were analysed, together with the genomic fingerprints of isolates generated using pulsed-field gel electrophoresis (PFGE). PGFE analyses were performed with isolates collected from the ear canals of goats or bulk milk in healthy herds, from individual clinical cases in different diseased herds at different times, and within a single herd during a severe outbreak, from various body sites including the ear canals at autopsy. Results showed that each isolate collected in healthy herds yielded a unique and characteristic PFGE profile. Isolates from diseased herds had profiles that were distinct for each outbreak and the group of 41 isolates from a single severe outbreak had 2 predominant PFGE profiles that persisted throughout the outbreak. These data suggest that while several distinct isolates are carried by healthy animals, only a few are responsible for the clinical signs observed within one herd during an outbreak. Whether this reflects differences in virulence between different field strains of MmmLC remains to be demonstrated.
Florence Tardy - One of the best experts on this subject based on the ideXlab platform.
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Comparison of isolates of Mycoplasma mycoides subspecies capri from asymptomatic and septicaemic goats.
Journal of Comparative Pathology, 2010Co-Authors: Florence Tardy, F Poumarat, Albert Tricot, Laure Maigre, L. Nguyen, D. Le GrandAbstract:Summary Strains of Mycoplasma mycoides subspecies capri ( Mmc ) are frequently isolated from goats with contagious agalactia, but they can also be recovered from herds that have shown no clinical signs of Mycoplasmosis for several years. The present study was conducted in order to explore the potential genetic and antigenic differences existing between an Mmc strain isolated from an outbreak (septicaemic) and a strain isolated from the ear canal of a goat belonging to a herd with no recent episode of Mycoplasmosis (carriage strain). The genomes of the two strains, compared by suppression subtractive hybridization, were shown to be poorly divergent. The two strains were inoculated into goats to produce specific antisera, but both induced fatal Mycoplasmosis. These results indicate that septicaemic and carriage strains cannot be distinguished by their genetic background or by their pathogenic capacity under experimental conditions.
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Mycoplasmoses of ruminants in France: recent data from the national surveillance network
BMC Veterinary Research, 2010Co-Authors: Myriam Chazel, Dominique Le Grand, Florence Tardy, Didier Calavas, F PoumaratAbstract:Background Ruminant mycoplasmoses are important diseases worldwide and several are listed by the World Organization for Animal Health to be of major economic significance. In France the distribution of mycoplasmal species isolated from clinical samples collected from diseased animals upon veterinary request, is monitored by a network known as VIGIMYC (for VIGIlance to MYCoplasmoses of ruminants). The veterinary diagnostic laboratories collaborating with VIGIMYC are responsible for isolating the mycoplasmas while identification of the isolates is centralized by the French Food Safety Agency (AFSSA) in Lyon. The VIGIMYC framework can also be used for specific surveys and one example, on the prevalence of M. bovis in bovine respiratory diseases, is presented here. Results Between 2003 and 2008, 34 laboratories were involved in the network and 1904 mycoplasma isolates, originating from the main ruminant-breeding areas, were identified. For cattle, the high prevalence of M. bovis in bronchopneumonia, notably in young animals, was confirmed by VIGIMYC and an associated specific survey, whereas the non-emergence of species such as M. alkalescens and M. canis was also demonstrated. The etiological agent of bovine contagious pleuropneumonia was never isolated. The principal Mycoplasmosis in goats was contagious agalactia with M. mycoides subsp. capri as main agent. Ovine mycoplasmoses, most of which were associated with pneumonia in lambs, were infrequently reported. One exception was ovine contagious agalactia (due to M. agalactiae ) that has recently re-emerged in the Pyrénées where it had been endemic for years and was also reported in Corsica, which was previously considered free. Conclusions Although VIGIMYC is a passive network and somewhat biased as regards sample collection and processing, it has provided, in this study, an overview of the main mycoplasmoses of ruminants in France. The French epidemiological situation is compared to those existing elsewhere in the world.
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mycoplasma mycoides subsp mycoides biotype large colony isolates from healthy and diseased goats prevalence and typing
Veterinary Microbiology, 2007Co-Authors: Florence Tardy, Pascale Mercier, Michel Solsona, E Saras, F PoumaratAbstract:Most severe goat Mycoplasmosis outbreaks in France are caused by Mycoplasma mycoides subsp. mycoides biotype LC (MmmLC). However, MmmLC can also be recovered from ear canals of healthy goats or from bulk milk collected in herds showing no clinical signs of Mycoplasmosis. To improve our understanding of how MmmLC strains are balanced between pathogenic ones and asymptomatically carried ones, descriptive epidemiological data were analysed, together with the genomic fingerprints of isolates generated using pulsed-field gel electrophoresis (PFGE). PGFE analyses were performed with isolates collected from the ear canals of goats or bulk milk in healthy herds, from individual clinical cases in different diseased herds at different times, and within a single herd during a severe outbreak, from various body sites including the ear canals at autopsy. Results showed that each isolate collected in healthy herds yielded a unique and characteristic PFGE profile. Isolates from diseased herds had profiles that were distinct for each outbreak and the group of 41 isolates from a single severe outbreak had 2 predominant PFGE profiles that persisted throughout the outbreak. These data suggest that while several distinct isolates are carried by healthy animals, only a few are responsible for the clinical signs observed within one herd during an outbreak. Whether this reflects differences in virulence between different field strains of MmmLC remains to be demonstrated.
Waldemar Rastawicki - One of the best experts on this subject based on the ideXlab platform.
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Use of recombinant P1 protein of Mycoplasma pneumoniae for the serodiagnosis of Mycoplasmosis
Medycyna doswiadczalna i mikrobiologia, 2012Co-Authors: Waldemar Rastawicki, Natalia Rokosz, Rafał Gierczyński, Marek JagielskiAbstract:INTRODUCTION Mycoplasma pneumoniae is a common etiologic agent of community-acquired respiratory infection. In serological diagnosis of M. pneumoniae infections tests have been described based on the purified P1 protein, which is the most important virulence factor of this pathogen, as antigen. The aim of his study was to express and purify a recombinant protein P1 M. pneumoniae and next evaluate this protein as high specific antigen in serodiagnosis of Mycoplasmosis. METHODS Protein P1 M pneumoniae was expressing in E. coli BL21 (DE3) using the pET-30 Ek/LIC expression vector. Based on published literature, we decided to express C-terminal region [P1-C1] encompassing amino acid residues 1160 to 1521. Purification was accomplished by immobilized metal (Ni2+) affinity column chromatography (His-trap). Serum samples collected from 221 patients with Mycoplasmosis, positive in complement fixation test (CFT), 87 patients with other then Mycoplasmosis bacterial infections and 80 blood donors were screened for anti-P1 recombinant protein IgA, IgG and IgM antibodies by using the home-made ELISA. RESULTS SDS-PAGE and Coomassie brilliant blue staining confirmed a high purity of the recombinant P1 protein preparation with an expected molecular mass of 39,7 kDa. The specificity of the recombinant protein was confirmed by western blot analysis using serum samples from rabbits immunized by M pneumoniae. The results of ELISA revealed that more then 70.0% of patients with Mycoplasmosis confirmed by CFT, had antibodies to recombinant P1 protein in diagnostically significant level (x + 2SD). The antibodies were found only sporadically in sera obtained from patients with other then Mycoplasmosis bacterial infections and clinically healthy persons. A comparison of results obtained in home-made ELISA with results of commercial western blot (Virotech) showed similar, ranged from 84.2% to 97.4%, compatible of results. The IgM antibodies to recombinant P1 protein were found in 87.2% sera obtained in acute phase of disease, in 80.0% sera obtained 2-4 weeks after onset of clinical symptoms and only in 43.8% sera obtained in chronic Mycoplasmosis. CONCLUSIONS The present study confirmed the earlier observations of the high usefulness of recombinant P1 protein for reliable serologic diagnosis of M. pneumoniae infection.
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Serodiagnosis of clinical infections caused by Mycoplasma pneumoniae in Poland in 1970-2010
Medycyna doswiadczalna i mikrobiologia, 2011Co-Authors: Stanisław Kałuzewski, Waldemar RastawickiAbstract:The aim of the study was evaluation of the reliability of serodiagnosis of Mycoplasmosis in Poland after replaced of classical assays, as complement fixation test (CFT) and immunoelectroprecipitation test (IEPT), by the ELISA method. The data were obtained from National Public Health Institute in Warsaw (NPHI), which receives quarterly reports of serologically confirmed infection from Sanitary and Epidemiological Stations through the country. Previously, from the 1970 to 1999 the serodiagnosis in Poland was performed only by uniform CFT using the same M. pneumoniae FH antigen prepared at the Mycoplasma Laboratory of NPHI. The first data of M. pneumoniae serological investigation performed by commercial ELISA, mainly Virotech, which gradually replaced the CFT, were obtained in 2000. In the studied period 1970-2010 a total of over 300 thousand patients with respiratory tract infections (85% were children below 18 years old) were tested. During these studies five epidemics of Mycoplasmosis were noted in Poland before 2000. However, after introduction of ELISA for serodiagnosis this characteristic distinct difference in epidemic and endemic occurrence of M pneumoniae infections have not been seen. In our opinion it may be caused by changes in the epidemiological pattern of M. pneumoniae infections in Poland as well as, paradoxical, by the decrease of sensitivity and specificity of serological investigation performed by ELISA since 2000. First of all, for the economical reasons 98% of the patients were tested by ELISA only once, secondly, the Mycoplasmosis in many laboratories was confirmed only on the basis of the presence of IgG antibodies. The results of our analysis showed also usefulness in the serodiagnosis of Mycoplasmosis, mainly during the first 2 weeks of the disease, of IEPT, which detect only specific IgM antibodies to M pneumoniae antigens.
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Evaluation of the usefulness of selected antigens of Mycoplasma pneumoniae for the serodiagnosis of Mycoplasmosis
Medycyna doswiadczalna i mikrobiologia, 2009Co-Authors: Waldemar Rastawicki, Natalia Rokosz, Marek JagielskiAbstract:Abstract A panel of 33 different antigens, among them lipoproteins, glicolipids and proteins, of Mycoplasma pneumoniae used in commercial western-blotting (Virotech) were assessed for reactivity with sera of patients with Mycoplasmosis and other bacterial infections of variable etiology. In addition, commercial ELISA (Virotech) with recombinant proteins as antigen and complement fixation test (CFT) with in-house prepared glicolipid-protein antigen were also assessed for comparison. The proteins with molecular weight of 170 kDa (P1) and 90 kDa (P90) were most recognized by the serum samples of patients with Mycoplasmosis. The reactions of proteins P50, P47 and Fts monomer with positive sera were not such often and the response was usually weak. The other proteins of M. pneumoniae, particularly P88, Repet. Prot. or P20, were recognized occasionally or at all. We observed also the often reactions ofglicolipids of M. pneumoniae with IgM antibodies. The result of the study showed that the commercial ELISA (Virotech) was equivalent in sensitivity and specificity to the CFT in the case of sera obtained in the acute phase of Mycoplasmosis (90.7% of agreement of results in the class IgA, 85.6% in the class IgG and 100% in the class IgM). Analytical specificity studied by screening serum samples from patients with different bacterial infections and blood donors have shown lower specificity of ELISA in compared to western-blotting. The present study confirmed the earlier observations of the high usefulness of P1 protein and P90 protein for reliable serologic diagnosis of acute M. pneumoniae infection.
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Occurrence of serologically verified Mycoplasma pneumoniae infections in Poland in 1970–1995
European Journal of Epidemiology, 1998Co-Authors: Waldemar Rastawicki, Stanisław Kałużewski, Marek JagielskiAbstract:This study analyses the numbers of serologically verified Mycoplasma pneumoniae infections in Poland in 1970–1995. The investigations were performed using the complement fixation test (CFT) with sonicated antigen in National Institute of Hygiene in Warsaw and since 1985 in 33 laboratories throughout the country. The result was accepted as positive when antibody titre was 60 or higher, or at least a four-fold increase in titre occured during the illness. During these studies five epidemics of Mycoplasmosis were noted in Poland. They occurred regularly every 5 years during the autumn-winter season in 1970/1971, 1975/1976, 1980/1981 and 1985/1986. The last epidemic, which started in 1991 and culminated in 1992–1993, seems to have inaugurated a change from epidemic to endemic occurrence of M. pneumoniae infection in Poland. At the peak of the epidemic, depending on the region of country, in 20–38% of patients with respiratory tract infection serological confirmation of Mycoplasmosis was obtained.
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Evaluation of occurrence of infections caused by Mycoplasma pneumoniae during 1970-1973 based on serological investigations
Przeglad epidemiologiczny, 1994Co-Authors: Stanisław Kałuzewski, Waldemar Rastawicki, Marek Jagielski, Kochman MAbstract:Abstract During the years 1970-1993 diagnostic serological tests directed against infection with M. pneumoniae were performed in 89,155 persons, mostly children at the preschool and school age with clinical symptoms of respiratory tract infections. Investigations were performed by application of the complement fixation test with cellular antigen of M. pneumoniae. Positive result was established when antibody titer was 60 or higher, or at least four-fold increase o titer occurred during the illness. During performance of these studies five epidemics of Mycoplasmosis were noted in Poland. They occurred during the autumn-winter season in 1970/71, 1975/76, 1980/81, 1985/86 and 1991-1993. At the peak of the epidemic depending of the region of country, in 25-38% of patients with pneumonia serological confirmation of Mycoplasmosis was established. In selected group of 251 persons which consisted in 87% of hospitalized patients with pneumonia, serological test was repeated at least twice during 7-10 days confirming mycoplasmal etiology of illness in 48.6% of cases. It was found that performance of serological test only once during first week of clinical symptoms of the disease decreases chances of Mycoplasmosis diagnosis by 53%.
Marek Jagielski - One of the best experts on this subject based on the ideXlab platform.
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Use of recombinant P1 protein of Mycoplasma pneumoniae for the serodiagnosis of Mycoplasmosis
Medycyna doswiadczalna i mikrobiologia, 2012Co-Authors: Waldemar Rastawicki, Natalia Rokosz, Rafał Gierczyński, Marek JagielskiAbstract:INTRODUCTION Mycoplasma pneumoniae is a common etiologic agent of community-acquired respiratory infection. In serological diagnosis of M. pneumoniae infections tests have been described based on the purified P1 protein, which is the most important virulence factor of this pathogen, as antigen. The aim of his study was to express and purify a recombinant protein P1 M. pneumoniae and next evaluate this protein as high specific antigen in serodiagnosis of Mycoplasmosis. METHODS Protein P1 M pneumoniae was expressing in E. coli BL21 (DE3) using the pET-30 Ek/LIC expression vector. Based on published literature, we decided to express C-terminal region [P1-C1] encompassing amino acid residues 1160 to 1521. Purification was accomplished by immobilized metal (Ni2+) affinity column chromatography (His-trap). Serum samples collected from 221 patients with Mycoplasmosis, positive in complement fixation test (CFT), 87 patients with other then Mycoplasmosis bacterial infections and 80 blood donors were screened for anti-P1 recombinant protein IgA, IgG and IgM antibodies by using the home-made ELISA. RESULTS SDS-PAGE and Coomassie brilliant blue staining confirmed a high purity of the recombinant P1 protein preparation with an expected molecular mass of 39,7 kDa. The specificity of the recombinant protein was confirmed by western blot analysis using serum samples from rabbits immunized by M pneumoniae. The results of ELISA revealed that more then 70.0% of patients with Mycoplasmosis confirmed by CFT, had antibodies to recombinant P1 protein in diagnostically significant level (x + 2SD). The antibodies were found only sporadically in sera obtained from patients with other then Mycoplasmosis bacterial infections and clinically healthy persons. A comparison of results obtained in home-made ELISA with results of commercial western blot (Virotech) showed similar, ranged from 84.2% to 97.4%, compatible of results. The IgM antibodies to recombinant P1 protein were found in 87.2% sera obtained in acute phase of disease, in 80.0% sera obtained 2-4 weeks after onset of clinical symptoms and only in 43.8% sera obtained in chronic Mycoplasmosis. CONCLUSIONS The present study confirmed the earlier observations of the high usefulness of recombinant P1 protein for reliable serologic diagnosis of M. pneumoniae infection.
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Evaluation of the usefulness of selected antigens of Mycoplasma pneumoniae for the serodiagnosis of Mycoplasmosis
Medycyna doswiadczalna i mikrobiologia, 2009Co-Authors: Waldemar Rastawicki, Natalia Rokosz, Marek JagielskiAbstract:Abstract A panel of 33 different antigens, among them lipoproteins, glicolipids and proteins, of Mycoplasma pneumoniae used in commercial western-blotting (Virotech) were assessed for reactivity with sera of patients with Mycoplasmosis and other bacterial infections of variable etiology. In addition, commercial ELISA (Virotech) with recombinant proteins as antigen and complement fixation test (CFT) with in-house prepared glicolipid-protein antigen were also assessed for comparison. The proteins with molecular weight of 170 kDa (P1) and 90 kDa (P90) were most recognized by the serum samples of patients with Mycoplasmosis. The reactions of proteins P50, P47 and Fts monomer with positive sera were not such often and the response was usually weak. The other proteins of M. pneumoniae, particularly P88, Repet. Prot. or P20, were recognized occasionally or at all. We observed also the often reactions ofglicolipids of M. pneumoniae with IgM antibodies. The result of the study showed that the commercial ELISA (Virotech) was equivalent in sensitivity and specificity to the CFT in the case of sera obtained in the acute phase of Mycoplasmosis (90.7% of agreement of results in the class IgA, 85.6% in the class IgG and 100% in the class IgM). Analytical specificity studied by screening serum samples from patients with different bacterial infections and blood donors have shown lower specificity of ELISA in compared to western-blotting. The present study confirmed the earlier observations of the high usefulness of P1 protein and P90 protein for reliable serologic diagnosis of acute M. pneumoniae infection.
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Occurrence of serologically verified Mycoplasma pneumoniae infections in Poland in 1970–1995
European Journal of Epidemiology, 1998Co-Authors: Waldemar Rastawicki, Stanisław Kałużewski, Marek JagielskiAbstract:This study analyses the numbers of serologically verified Mycoplasma pneumoniae infections in Poland in 1970–1995. The investigations were performed using the complement fixation test (CFT) with sonicated antigen in National Institute of Hygiene in Warsaw and since 1985 in 33 laboratories throughout the country. The result was accepted as positive when antibody titre was 60 or higher, or at least a four-fold increase in titre occured during the illness. During these studies five epidemics of Mycoplasmosis were noted in Poland. They occurred regularly every 5 years during the autumn-winter season in 1970/1971, 1975/1976, 1980/1981 and 1985/1986. The last epidemic, which started in 1991 and culminated in 1992–1993, seems to have inaugurated a change from epidemic to endemic occurrence of M. pneumoniae infection in Poland. At the peak of the epidemic, depending on the region of country, in 20–38% of patients with respiratory tract infection serological confirmation of Mycoplasmosis was obtained.
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Evaluation of occurrence of infections caused by Mycoplasma pneumoniae during 1970-1973 based on serological investigations
Przeglad epidemiologiczny, 1994Co-Authors: Stanisław Kałuzewski, Waldemar Rastawicki, Marek Jagielski, Kochman MAbstract:Abstract During the years 1970-1993 diagnostic serological tests directed against infection with M. pneumoniae were performed in 89,155 persons, mostly children at the preschool and school age with clinical symptoms of respiratory tract infections. Investigations were performed by application of the complement fixation test with cellular antigen of M. pneumoniae. Positive result was established when antibody titer was 60 or higher, or at least four-fold increase o titer occurred during the illness. During performance of these studies five epidemics of Mycoplasmosis were noted in Poland. They occurred during the autumn-winter season in 1970/71, 1975/76, 1980/81, 1985/86 and 1991-1993. At the peak of the epidemic depending of the region of country, in 25-38% of patients with pneumonia serological confirmation of Mycoplasmosis was established. In selected group of 251 persons which consisted in 87% of hospitalized patients with pneumonia, serological test was repeated at least twice during 7-10 days confirming mycoplasmal etiology of illness in 48.6% of cases. It was found that performance of serological test only once during first week of clinical symptoms of the disease decreases chances of Mycoplasmosis diagnosis by 53%.
Glenn F Browning - One of the best experts on this subject based on the ideXlab platform.
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Genetic diversity of Mycoplasma arginini isolates based on multilocus sequence typing.
Veterinary Microbiology, 2015Co-Authors: Olusola M Olaogun, Anna Kanci, Stuart R Barber, Kelly A Tivendale, Philip F Markham, Marc S Marenda, Glenn F BrowningAbstract:The contribution of Mycoplasma arginini to Mycoplasmosis in small ruminants remains unclear because it is recovered from both healthy and diseased animals. In order to gain a better understanding of any relationships between isolates from different sites and different geographical locations, we developed a method for genotyping M. arginini using multilocus sequence typing (MLST). A MLST scheme based on five housekeeping genes was used to characterize M. arginini isolates from flocks of sheep and goats. A high level of genetic variability was detected between strains and within herds.
