Hamana, K; Nakata, K
Cellular levels of diaminopropane, putrescine and cadaverine, and decarboxylase activities to produce these diamines in six species (16 strains) of Haemophilus and four species (5 strains) of Actinobacillus belonging to the family Pasteurellaceae of the gamma subclass of the class Proteobacteria, were determined by high performance liquid chromatography (HPLC). Diaminopropane was ubiquitously distributed within all Haemophilus and Actinobacillus species, and L-2,4-diaminobutyric acid decarboxylase activity was detected in them. Putrescine and ornithine decarboxylase activity were found in H. aphrophilus, H. parainfluenzae and H. influenzae (type a, b, d, e and f except for type c) but not detected in H. aegyptius, H. parahaemolyticus, H. ducreyi and Actinobacillus species. Cadaverine occurred in H. aphrophilus, H. aegyptius, H. influenzae, H. parainfluenzae, A. actinomycetemcomitans, A. equuli and A. lignieresii, whereas their lysine decarboxylase activity was scarcely detected. Cadaverine was not found in H. parahaemolyticus, H. ducreyi and A. suis. The diamine profile serves as a phenotypic marker for the chemotaxonomic classification of the family Pasteurellaceae.
Calcutt, Michael J; Foecking, Mark F; Mhlanga-Mutangadura, Tendai; Reilly, Thomas J
The assembled and annotated genome of Actinobacillus suis ATCC 33415(T) is reported here. The 2,501,598-bp genome encodes 2,246 open reading frames (ORFs) with strain variable incursion of an integrative conjugative element into a tRNA locus. Comparative analysis of the deduced gene set should inform our understanding of pathogenesis, genomic plasticity, and serotype variation.
Daignault, D.; Chouinard, L.; Møller, Kristian
Actinobacillus suis has been isolated from the lungs of a 9-month-old cat. The bacterium was characterized biochemically as well as genetically, and its sensitivity profile to different antimicrobial agents was established. The role of this isolate in the cat's condition is discussed....
Jantzen, E; Berdal, B P; Omland, T
The fatty acid composition of 35 Haemophilus influenzae strains was found to be grossly similar and characterized by relatively large amounts of 14:0, 3-OH-14:0, 16:1 and 16:0. The three C18 fatty acids 18:2, 18:1 and 18:0 were also present, but in much lower concentrations. This general pattern was also found for most of the other species of Haemophilus examined (H. aegyptius, H. aphrophilus, H. canis, H. gallinarum, H. haemolyticus, and H. parainfluenzae). Small but distinct quantitative discrepancies were detected for H. ducreyi and the haemin-independent species H. paraphrohaemolyticus, H. paraphrophilus and H. suis. Actinobacillus actinomycetemcomitans was found to be indistinguishable from H. influenzae. Pasteurella multocida also exhibited a fatty acid pattern closely related to that of Haemophilus, but could be distinguished by its higher concentration levels of the C18 fatty acids. The fatty acid pattern of H. vaginalis was considerably different from those of the other species examined. This species lacked 3-OH-14:0 and 18:2 and contained small amounts of 14:0 and 16:0, whereas 18:1 and 18:0 were the major constituents.
Actinobacillus suis and Actinobacillus equuli, emergent pathogens of septic embolic nephritis, a new challenge for the swine industry Actinobacillus suis y Actinobacillus equuli, patógenos emergentes de nefritis embólica séptica, un nuevo desafío para la industria porcina
Full Text Available Kidney lesions are an important cause of tissue condemnation in slaughterhouses. In addition to the potential public health implications, organ condemnations have a significant economic impact on the food animal industry. The condition classified broadly as "nephritis" is one of the main causes of tissue condemnation. Embolic nephritis resembling Actinobacillus equuli infection in foals has been recently detected in sows and market hogs. Actinobacillus suis is phenotypically and phylogenetically closely related to A. equuli. Both are Gram-negative bacteria, not easy to detect in routine exams. A. suis is an opportunistic pathogen that can produce fatal septicaemia in pigs, pneumonia, polyarthritis, septic embolic nephritis, abortion and mummified foetuses. Outbreaks of clinical disease appear to occur more frequently in high-health-status herds. In adult pigs the skin lesions may be confused with porcine erysipelas. A. suis and A. equuli are emerging opportunistic pathogens in the porcine industry and both have potential public health consequences to people that handles meat products. The objective of this paper is to present a literature review regarding the role of A. suis and A. equuli in the pathogenesis of nephritis in swine.Las lesiones renales son una causa importante de decomiso en los mataderos. Además de las posibles consecuencias en salud pública, el decomiso de órganos tiene un gran impacto económico en la industria de alimento animal. Recientemente, nefritis embólica séptica con lesiones semejantes a infecciones con Actinobacillus equuli en potrillos ha sido detectada en reproductoras y cerdos con peso de mercado. Actinobacillus equuli es fenotípica y genéticamente similar a Actinobacillus suis. Ambas son bacterias Gram-negativas difíciles de diagnosticar en exámenes de rutina. A. suis es un patógeno oportunista capaz de producir septicemia en cerdos, neumonía, poliartritis, nefritis embólica séptica, aborto y fetos
Rafael Silveira Carreon
Full Text Available Actinobacillus suis (A.suis surgiu como uma grande ameaça aos plantéis suínos norte-americanos. Os sinais clínicos e as lesões são particularmente variáveis e podem lembrar aquelas causadas por outros organismos, como o Actinobacillus pleuropneumoniae (App, podendo ter como causa a similaridade na produção das toxinas ApxI e ApxII. Os objetivos do estudo foram confirmar a produção das toxinas ApxI e ApxII, investigar a produção de toxina geneticamente semelhante à Apx III e analisar as proteínas totais, verificando se existe similaridade entre os isolados provenientes de diferentes plantéis de suínos norte-americanos. Neste estudo, todas as cepas de A. suis foram positivas para os genes codificadores das toxinas ApxI e ApxII, usando o método de reação em cadeia de polimerase - multiplex (PCR-multiplex; e as proteínas totais de 70 amostras de A. suis, oriundos de diferentes plantéis suínos norte-americanos, foram analisadas por meio de eletroforese em gel de poliacrilaminda desnaturante (SDS-PAGE e foram idênticas. A similaridade eletroforética observada entre as proteínas totais das bactérias analisadas indica a possibilidade de haver uma proteção cruzada a partir de uma provável vacina universal desenvolvida com esses antígenos para A. suis.Actinobacillus suis (A. suis has arisen as a great threat to the North American hog herds. The clinical symptoms and lesions are particularly variable and may resemble the same caused by other pathogenic organisms, such as Actinobacillus pleuropneumoniae (App, which can similarly lead to the production of the toxins ApxI and ApxII. This study aimed to confirm the production of the toxins ApxI and ApxII, as well as, to investigate the production of toxins that are genetically similar to ApxIII, and analyze total protein to verify whether there is any similarity among the isolated samples obtained from different North American hog herds. In this study, all the strains of A. suis
Vilalta Sans, Carles
La marbofloxacina (MB) és una fluoroquinolona de tercera generació àmpliament usada en diferents espècies per tractar sobretot infeccions respiratòries. Aquest antibiòtic posseeix un ampli espectre d’activitat que inclou dos dels principals patògens associats al complexe respiratori porcí (CRP), Actinobacillus pleuropneumoniae (APP) i Haemophilus parasuis (HP). APP és l’agent etiològic de la pleuropneumònia porcina i pot romandre a les tonsil·les dels porcs sense mostrar cap mena de símptoma ...
Vilalta Sans, Carles; Cristòfol Adell, Carles
La marbofloxacina (MB) és una fluoroquinolona de tercera generació àmpliament usada en diferents espècies per tractar sobretot infeccions respiratòries. Aquest antibiòtic posseeix un ampli espectre d'activitat que inclou dos dels principals patògens associats al complexe respiratori porcí (CRP), Actinobacillus pleuropneumoniae (APP) i Haemophilus parasuis (HP). APP és l'agent etiològic de la pleuropneumònia porcina i pot romandre a les tonsil·les dels porcs sense mostrar cap mena de símptoma ...
Evaluation of the RapID NH system for identification of Haemophilus somnus, Pasteurella multocida, Pasteurella haemolytica, and Actinobacillus pleuropneumoniae isolated from cattle and pigs with respiratory disease.
Salmon, S A; Watts, J L; Yancey, R J
Haemophilus somnus, Pasteurella haemolytica, Pasteurella multocida, and Actinobacillus pleuropneumoniae from cattle and pigs with respiratory disease were used to evaluate the RapID NH system (Innovative Diagnostics, Atlanta, Ga.). Minor modifications of the RapID NH system to include animal source and growth requirements would permit the identification of all isolates tested.
Dayao, Dae; Gibson, J S; Blackall, P J; Turni, C
To identify genes associated with the observed antimicrobial resistance in Actinobacillus pleuropneumoniae, Haemophilus parasuis and Pasteurella multocida isolated from Australian pigs. Isolates with known phenotypic resistance to β-lactams, macrolides and tetracycline were screened for the presence of antimicrobial resistance genes. A total of 68 A. pleuropneumoniae, 62 H. parasuis and 20 P. multocida isolates exhibiting phenotypic antimicrobial resistance (A. pleuropneumoniae and P. multocida) or elevated minimal inhibitory concentrations (MICs) (H. parasuis) to any of the following antimicrobial agents - ampicillin, erythromycin, penicillin, tetracycline, tilmicosin and tulathromycin - were screened for a total of 19 associated antimicrobial resistance genes (ARGs) by PCR. The gene bla ROB-1 was found in all ampicillin- and penicillin-resistant isolates, but none harboured the bla TEM-1 gene. The tetB gene was found in 76% (74/97) of tetracycline-resistant isolates, 49/53 A. pleuropneumoniae, 17/30 H. parasuis and 8/14 P. multocida. One A. pleuropneumoniae isolate harboured the tetH gene, but none of the 97 isolates had tetA, tetC, tetD, tetE, tetL, tetM or tetO. A total of 92 isolates were screened for the presence of macrolide resistance genes. None was found to have ermA, ermB, ermC, erm42, mphE, mefA, msrA or msrE. The current study has provided a genetic explanation for the resistance or elevated MIC of the majority of isolates of Australian porcine respiratory pathogens to ampicillin, penicillin and tetracycline. However, the macrolide resistance observed by phenotypic testing remains genetically unexplained and further studies are required. © 2016 Australian Veterinary Association.
. and Aggregatibacter segnis comb. nov., and emended description of Aggregatibacter aphrophilus to include V factor-dependent and V factor-independent isolates, Reclassification of Actinobacillus actinomycetemcomitans, Haemophilus aphrophilus, Haemophilus paraphrophilus and Haemophilus segnis as Aggregatibacter actinomycetemcomitans gen. nvo., comb. nov., Aggregatibacter aphrophilus comb. nov
Nørskov-Lauritsen, N.; Kilian, Mogens
The aim of this study was to reinvestigate the relationships and the generic affiliations of the species Actinobacillus actinomycetemcomitans, Haemophilus aphrophilus, Haemophilus paraphrophilus and Haemophilus segnis. The nicotinamide phosphoribosyltransferase gene (nadV) conferring V factor-ind......)=NCTC 5906(T)) and Aggregatibacter segnis comb. nov. (type strain HK316(T)=ATCC 33393(T)=CCUG 10787(T)=CCUG 12838(T)=CIP 103292(T)=NCTC 10977(T)). The species of the genus Aggregatibacter are independent of X factor and variably dependent on V factor for growth in vitro......The aim of this study was to reinvestigate the relationships and the generic affiliations of the species Actinobacillus actinomycetemcomitans, Haemophilus aphrophilus, Haemophilus paraphrophilus and Haemophilus segnis. The nicotinamide phosphoribosyltransferase gene (nadV) conferring V factor......-independent growth was identified in Haemophilus aphrophilus. The gene encodes a polypeptide of 462 amino acids that shows 74.5 % amino acid sequence identity to the corresponding enzyme from Actinobacillus actinomycetemcomitans. Ten isolates of Haemophilus paraphrophilus all carried a nadV pseudogene. DNA from...
Kamp, E M; van Leengoed, L A
Reference strains of serotypes 1 to 12 of Actinobacillus (Haemophilus) pleuropneumoniae were cultured in Eagle minimal essential medium with 10% Serum Plus. Culture supernatants were examined for cytotoxicity to alveolar macrophages and for the ability to hemolyze sheep erythrocytes. All strains except the reference strain of serotype 6 produced cytotoxin, whereas only serotypes 1, 5, 9, 10, and 11 produced hemolysin. Both cytotoxin and hemolysin appeared to be heat labile. Antisera were rais...
Wallgren, Per; Nörregård, Erik; Molander, Benedicta; Persson, Maria; Ehlorsson, Carl-Johan
Respiratory illness is traditionally regarded as the disease of the growing pig, and has historically mainly been associated to bacterial infections with focus on Mycoplasma hyopneumoniae and Actinobacillus pleuropneumoniae. These bacteria still are of great importance, but continuously increasing herd sizes have complicated the scenario and the influence of secondary invaders may have been increased. The aim of this study was to evaluate the presence of A. pleuropneumoniae and M. hyopneumoniae, as well as that of the secondary invaders Pasteurella multocida and Streptococcus suis by serology in four pig herds (A-D) using age segregated rearing systems with high incidences of pleuritic lesions at slaughter. Pleuritic lesions registered at slaughter ranged from 20.5 to 33.1 % in the four herds. In herd A, the levels of serum antibodies to A. pleuropneumoniae exceeded A450 > 1.5, but not to any other microbe searched for. The seroconversion took place early during the fattening period. Similar levels of serum antibodies to A. pleuropneumoniae were also recorded in herd B, with a subsequent increase in levels of antibodies to P. multocida. Pigs seroconverted to both agents during the early phase of the fattening period. In herd C, pigs seroconverted to P. multocida during the early phase of the fattening period and thereafter to A. pleuropneumoniae. In herd D, the levels of antibodies to P. multocida exceeded A450 > 1.0 in absence (A450 pleuropneumoniae. The levels of serum antibodies to M. hyopneumoniae and to S. suis remained below A450 pleuropneumoniae and P. multocida, either alone or in combination with each other. Seroconversion to M. hyopneumoniae late during the rearing period or not at all, confirmed the positive effect of age segregated rearing in preventing or delaying infections with M. hyopneumoniae. The results obtained highlight the necessity of diagnostic investigations to define the true disease pattern in herds with a high incidence
Full Text Available The apxIC genes of the Actinobacillus pleuropneumoniae serovar 5 (SC-1, encoding the ApxIactivating proteins, was deleted by a method involving sucrose counter-selection. In this study, a mutant strain of A. pleuropneumoniae (SC-1 was constructed and named DapxIC/ ompP2. The mutant strain contained foreign DNA in the deletion site of ompP2 gene of Haemophilus parasuis. It showed no haemolytic activity and lower virulence of cytotoxicity in mice compared with the parent strain, and its safety and immunogenicity were also evaluated in mice. The LD50 data shown that the mutant strain was attenuated 30-fold, compared with the parent strain (LD50 of the mutant strain and parent strain in mice were determined to be 1.0 × 107 CFU and 3.5 × 105 CFU respectively. The mutant strain that was attenuated could secrete inactivated ApxIA RTX toxins with complete antigenicity and could be used as a candidate live vaccine strain against infections of A. pleuropneumoniae and H. parasuis.
Liu, Qiong; Gong, Yuheng; Cao, Yuqin; Wen, Xintian; Huang, Xiaobo; Yan, Qigui; Huang, Yong; Cao, Sanjie
The apxIC genes of the Actinobacillus pleuropneumoniae serovar 5 (SC-1), encoding the ApxIactivating proteins, was deleted by a method involving sucrose counter-selection. In this study, a mutant strain of A. pleuropneumoniae (SC-1) was constructed and named DapxIC/ ompP2. The mutant strain contained foreign DNA in the deletion site of ompP2 gene of Haemophilus parasuis. It showed no haemolytic activity and lower virulence of cytotoxicity in mice compared with the parent strain, and its safety and immunogenicity were also evaluated in mice. The LD50 data shown that the mutant strain was attenuated 30-fold, compared with the parent strain (LD50 of the mutant strain and parent strain in mice were determined to be 1.0 × 10(7) CFU and 3.5 × 10(5) CFU respectively). The mutant strain that was attenuated could secrete inactivated ApxIA RTX toxins with complete antigenicity and could be used as a candidate live vaccine strain against infections of A. pleuropneumoniae and H. parasuis.
Kiorpes, A L; Bäckström, L R; Collins, M T; Kruse, G O
These experiments tested the hypothesis that long-acting oxytetracycline (oxytetracycline-LA) was more effective than regular oxytetracycline in preventing porcine pleuropneumonia when administered either 24 or 48 h prior to experimental challenge with virulent strains of Actinobacillus pleuropneumoniae. Two experiments (1 and 2) were conducted using growing pigs (average weight 12-15 kg). Antibiotic treatments were administered once intramuscularly at 20 mg/kg body weight; controls received ...
Full Text Available The Haemophilus influenzae HMW1 adhesin is an important virulence exoprotein that is secreted via the two-partner secretion pathway and is glycosylated at multiple asparagine residues in consensus N-linked sequons. Unlike the heavily branched glycans found in eukaryotic N-linked glycoproteins, the modifying glycan structures in HMW1 are mono-hexoses or di-hexoses. Recent work demonstrated that the H. influenzae HMW1C protein is the glycosyltransferase responsible for transferring glucose and galactose to the acceptor sites of HMW1. An Actinobacillus pleuropneumoniae protein designated ApHMW1C shares high-level homology with HMW1C and has been assigned to the GT41 family, which otherwise contains only O-glycosyltransferases. In this study, we demonstrated that ApHMW1C has N-glycosyltransferase activity and is able to transfer glucose and galactose to known asparagine sites in HMW1. In addition, we found that ApHMW1C is able to complement a deficiency of HMW1C and mediate HMW1 glycosylation and adhesive activity in whole bacteria. Initial structure-function studies suggested that ApHMW1C consists of two domains, including a 15-kDa N-terminal domain and a 55-kDa C-terminal domain harboring glycosyltransferase activity. These findings suggest a new subfamily of HMW1C-like glycosyltransferases distinct from other GT41 family O-glycosyltransferases.
Pharmacokinetic/pharmacodynamic evaluation of marbofloxacin in the treatment of Haemophilus parasuis and Actinobacillus pleuropneumoniae infections in nursery and fattener pigs using Monte Carlo simulations.
Vilalta, C; Giboin, H; Schneider, M; El Garch, F; Fraile, L
This study evaluated the theoretical clinical outcome of three marbofloxacin posology regimens in two groups of pigs (weaners and fatteners) for the treatment of Actinobacillus pleuropneumoniae (App) and Haemophilus parasuis (Hp) infection and the appearance of resistant bacteria due to the antibiotic treatment. The probability of target attainment (PTA) for pharmacokinetic/pharmacodynamics (PK/PD) ratios associated with clinical efficacy and with the appearance of antimicrobial resistance for fluoroquinolones at each minimum inhibitory concentration (MIC) or mutant prevention concentration (MPC) were calculated, respectively. The cumulative fraction of response (CFR) was calculated for the three posology regimens against App and they ranged from 91.12% to 96.37% in weaners and from 93% to 97.43% in fatteners, respectively. In the case of Hp, they ranged from 80.52% to 85.14% in weaners and from 82.01% to 88.49% in fatteners, respectively. Regarding the PTA of the PK/PD threshold associated with the appearance of antimicrobial resistance, results showed that marbofloxacin would prevent resistances in most of the animals up to the MPC value of 1 μg/mL.
Bøg, Yang S.; Andresen, Lars Ole; Bastholm, L.;
antigens were detected with the Mab in iron-starved Actinobacillus lignieresii, Actinobacillus porcinus, Actinobacillus minor Haemophilus influenzae. and Haemophilus parasuis. Using an enzyme-linked immunosorbent assay (ELISA) based on the Mab 1.48, Tbp2 could be detected in both recombinant E. coli...
Choi, Kyoung-Jae; Grass, Susan; Paek, Seonghee; St Geme, 3rd, Joseph W; Yeo, Hye-Jeong
The Haemophilus influenzae HMW1 adhesin is an important virulence exoprotein that is secreted via the two-partner secretion pathway and is glycosylated at multiple asparagine residues in consensus N-linked sequons...
Fu, Shulin; Ou, Jiwen; Zhang, Minmin; Xu, Juan; Liu, Huazhen; Liu, Jinlin; Yuan, Fangyan; Chen, Huanchun; Bei, Weicheng
Haemophilus parasuis and Actinobacillus pleuropneumoniae both belong to the family Pasteurellaceae and are major respiratory pathogens that cause large economic losses in the pig industry worldwide. We previously constructed an attenuated A. pleuropneumoniae serovar 1 live vaccine prototype, SLW05 (ΔapxIC ΔapxIIC ΔapxIV-ORF1), which is able to produce nontoxic but immunogenic ApxIA, ApxIIA, and ApxIVA. This triple-deletion mutant strain was shown to elicit protective immunity against virulent A. pleuropneumoniae. In the present study, we investigated whether immunization with SLW05 could also protect against lethal challenge with virulent H. parasuis SH0165 (serovar 5) or MD0322 (serovar 4). The SLW05 strain was found to elicit a strong humoral antibody response in pigs and to confer significant protection against challenge with a lethal dose of H. parasuis SH0165 or MD0322. IgG subtype analysis revealed that SLW05 induces a bias toward a Th1-type immune response and stimulates interleukin 2 (IL-2) and gamma interferon (IFN-γ) production. Moreover, antisera from SLW05-vaccinated pigs efficiently inhibited both A. pleuropneumoniae and H. parasuis growth in a whole-blood assay. This is the first report that a live attenuated A. pleuropneumoniae vaccine with SLW05 can protect against lethal H. parasuis infection, which provides a novel approach for developing an attenuated H. parasuis vaccine.
Differentiation of Actinobacillus pleuropneumoniae strains by sequence analysis of 16S rDNA and ribosomal intergenic regions, and development of a species specific oligonucleotide for in situ detection
Fussing, Vivian; Paster, Bruce J.; Dewhirst, Floyd E.;
The aims of this study were to characterize and determine intraspecies and interspecies relatedness of Actinobacillus pleuropneumoniae to Actinobacillus lignieresii and Actinobacillus suis by sequence analysis of the ribosomal operon and to find a species-specific area for in situ detection of A...
Poggenborg, René; Gaïni, Shahin; Kjaeldgaard, Poul
Meningitis and spondylodiscitis caused by Streptococcus suis is a rare disease which is contracted by occupational exposure to pigs. We report a 54-y-old pig-farm worker with S. suis meningitis and septicaemia complicated with thoracal and lumbar spine spondylodiscitis. The S. suis strain involve...... in this case report was identified as serotype 14, which has only been described in 2 previous cases. It is important to report infection with S. suis as a work accident for compensation if the patient has been occupationally exposed to pigs....
胡军勇; 汤细彪; 汤电; 刘望宏; 倪德斌; 吴斌
为了解我国规模化猪场链球菌和副猪嗜血杆菌的耐药情况,用纸片扩散法对临床分离的112株猪链球菌和92株副猪嗜血杆菌进行23种药物的敏感性试验.结果表明,猪链球菌对林可胺类、大环内酯类、硝基呋喃类药物的耐药率均在90％以上,对链霉素、庆大霉素、卡那霉素、阿米卡星、多西环素的耐药率在60％～90％之间,而对β-内酰胺类和氟喹诺酮类的耐药率相对较低.副猪嗜血杆菌对四环素耐药率最高(78.3％),对螺旋霉素、复方磺胺甲(嗯)唑、克林霉素、阿米卡星、林可霉素、新霉素的耐药率在50％～70％之间,对头孢类和氟喹诺酮类耐药率相对较低.2种细菌对不同种类药物的敏感性各异,并且多重耐药性严重,主要耐药谱具有多样性.%One hundred and twelve Streptococcus suis and 92 Haemophilus parasuis were isolated from pig farm to investigate susceptibility of the two bacteria strains to 23 antimicrobials by using disk diffusion method. Results showed that for the S. Suis strain,the resistance rates of lincosamtde,macroli-des and nitrofurans were all above 90%,followed by streptomycin,gentamicin,kanamycin,amikacin and doxycycline with the resistance rates ranged from 60% to 90% and resistance rates of β-lactams and quinolones were relatively lower. For the H. Parasuis strain, the resistance rate of tetracycline was the highest (78. 3%), followed by spiramycin, sulfamethoxazole/TMP, clindymycin, lincomycin, amikacin and neomycin varied from 50% to 70% and resistance rates of cephalosporins and quinolones were relatively lower. The susceptibility of the two kinds of bacteria to the antimicrobials were different, multiple resistance was severe and the resistance profiles were various.
A collection of 426 Haemophilus strains isolated from people with infectious diseases and from the normal flora of mucous membranes in humans and various animal species was studied in an attempt to revise and improve the taxonomy of the genus Haemophilus. The examinations included the determination of a number of biochemical and physiological properties, of which several had not previously been applied to the taxonomy of haemophili. The resulting data reavealed many hitherto unrecognized characters of taxonomic significance and several of the species can now be more accurately defined. The classification presented is supported by the DNA base composition of a large number of representative strains. A diagnostic key to the different taxa is presented. Haemophilus influenzae and H. parainfluenzae have been subdivided into a number of biotypes. It is possible to demonstrate a relationship between the individual biotypes of H. influenzae and the origin of the strains assigned to them. The results indicate that H. aegyptius, H. parahaemolyticus and H. paraphrohaemolyticus do not merit specific status. Four unnamed taxa of V-factor-dependent haemophili have been recognized. The name Haemophilus segnis is proposed for one of these taxa, which consists mainly of strains isolated from the human oral cavity. It is demonstrated that the name H. Ducreyi has been used for different groups of bacteria, and that only one of these groups can legitimately be assigned to the genus Haemophilus. Haemolytic V-factor-dependent strains from swine, previously included in H. parahaemolyticus, are significantly different from strains of human origin and should be named H. pleuropneumoniae. None of the strains from swine and fowls were haemin-dependent. The relationships of these strains to the species H. suis and H. gallinarum, and to H. parasuis and H. paragallinarum are discussed. Haemophilus piscium is shown not to belong to the genus Haemophilus. The taxonomic position of H. aphrophilus
García-Cuéllar, C; Montañez, C; Tenorio, V; Reyes-Esparza, J; Durán, M J; Negrete, E; Guerrero, A; de la Garza, M
Actinobacillus pleuropneumoniae causes pleuropneumonia in swine. This bacterium secretes proteases that degrade porcine hemoglobin and IgA in vitro. To further characterize A. pleuropneumoniae proteases, we constructed a genomic library expressed in Escherichia coli DH5alpha, and selected a clone that showed proteolytic activity. The recombinant plasmid carries an 800-base pair A. pleuropneumoniae gene sequence that.codes for a 24-kDa polypeptide. A 350-base pair PstI fragment from the sequence hybridized at high stringency with DNA from 12 serotypes of A. pleuropneumoniae, but not with DNA from Actinobacillus suis, Haemophilus parasuis, Pasteurella haemolytica, Pasteurella multocida A or D, or E. coli DH5alpha, thus showing specificity for A. pleuropneumoniae. The expressed polypeptide was recognized as an antigen by convalescent-phase pig sera. Furthermore, a polyclonal antiserum developed against the purified polypeptide recognized an A. pleuropneumoniae oligomeric protein in both crude-extract and cell-free culture media. This recombinant polypeptide cleaved azocoll, gelatin, and actin. Inhibition of the proteolytic activity by diethylpyrocarbonate suggests that this polypeptide is a zinc metalloprotease. Images Figure 1. Figure 2. Figure 3. Figure 4. Figure 6. Figure 7. PMID:10805246
.... For the treatment and control of swine respiratory disease (SRD) associated with Actinobacillus pleuropneumoniae, Pasteurella multocida, Haemophilus parasuis, and Streptococcus suis. (iii) Limitations. Animals...
Full Text Available This paper reports on the development and validation of a loop-mediated isothermal amplification assay (LAMP for the rapid and specific detection of Actinobacillus pleuropneumoniae (A. pleuropneumoniae. A set of six primers were designed derived from the dsbE-like gene of A.pleuropneumoniae and validate the assay using 9 A. pleuropneumoniae reference/field strains, 132 clinical isolates and 9 other pathogens. The results indicated that positive reactions were confirmed for all A. pleuropneumoniae strains and specimens by LAMP at 63ºC for 60 min and no cross-reactivity were observed from other non-A.pleuropneumoniae including Haemophilus parasuis, Escherichia coli, Pasteurella multocida, Bordetella bronchiseptica, Streptococcus suis, Salmonella enterica, Staphylococcus, porcine reproductive and respiratory syndrome virus (PRRSV, and Pseudorabies virus. The detection limit of the conventional PCR was 10² CFU per PCR test tube, while that of the LAMP was 5 copies per tube. Therefore, the sensitivity of LAMP was higher than that of PCR. Moreover, the LAMP assay provided a rapid yet simple test of A. pleuropneumoniae suitable for laboratory diagnosis and pen-side detection due to ease of operation and the requirement of only a regular water bath or heat block for the reaction.
Menegueti, Mayra Goncalves; Machado-Viana, Jaciara; Gaspar, Gilberto Gambero; Nicolini, Edson Antonio; Basile-Filho, Anibal; Auxiliadora-Martins, Maria
Haemophilus parainfluenzae, which belongs to the HACEK (Haemophilus ssp, Actinobacillus actinomycetemcomitans, Cardiobacterium hominis, Eikenella corrodens, and Kingella kingae) group, is a rare cause of subacute endocarditis and may lead to ischemic stroke. A 65-year-old female patient previously diagnosed with rheumatic valve disease was submitted to surgical mitral valve repair in 1996. Physical examination did not reveal any murmurs; physical examination of the lungs and abdomen was norma...
... Hib Vaccination Hib Vaccination Meningitis Pneumonia Sepsis About Haemophilus influenzae Disease Recommend on Facebook Tweet Share Compartir H. ... severe, such as a bloodstream infection. Types of Haemophilus influenzae Infections Infections caused by these bacteria... Causes, How ...
... Actinobacillus pleuropneumoniae, Pasteurella multocida, Haemophilus parasuis, and Streptococcus suis. (iii... fever, pneumonia) associated with Mannheimia haemolytica, Pasteurella multocida, and Histophilus somni.... (2) Cattle. The formulation described in paragraph (a)(2) of this section is used as follows:...
Hedegaard, J; Okkels, H; Bruun, B;
A 453 bp fragment of infB, the gene encoding translation initiation factor 2, was sequenced and compared from 66 clinical isolates and type strains of Haemophilus species and related bacteria. Analysis of the partial infB sequences obtained suggested that the human isolates dependent on X and V...... factor, H. influenzae, H. haemolyticus, H. aegyptius and some cryptic genospecies of H. influenzae, were closely related to each other. H. parainfluenzae constituted a heterogeneous group within the boundaries of the genus, whereas H. aphrophilus/paraphrophilus and Actinobacillus actinomycetemcomitans...... were only remotely related to the type species of the genus Haemophilus H. parahaemolyticus and H. paraphrohaemolyticus took up an intermediary position and may not belong in the genus Haemophilus sensu stricto. Ambiguous results were obtained with seven isolates tentatively identified as H. segnis...
Mazloum, H A; Kilian, M; Mohamed, Z M; Said, M D
This study aimed at clarifying the relationship of Haemophilus aegyptius and Haemophilus influenzae isolated from acute conjunctivitis in Egypt. Twenty-nine freshly isolated strains selected from a large clinical material were examined for morphological and growth characteristics, biochemical properties and susceptibility to selected antibiotics. H. aegyptius strains were clearly differentiated from strains of H. influenzae by their inability to grow on tryptic soy agar containing X + V factors, by their susceptibility to trooleandomycin, by a distinct bacillary morphology, and, in part, by not fermenting xylose. The results confirm that H. aegyptius is distinct from H. influenzae and provides reproducible means of differentiating the two species.
Li, Lu; Sun, Lili; Song, Yunfeng; Wu, Xinjuan; Zhou, Xuan; Liu, Ziduo; Zhou, Rui
LuxS, a conserved bacterial enzyme involved in the activated methyl cycle, catalyzes S-ribosylhomocysteine (SRH) into homocysteine and AI-2 (the inter-species quorum-sensing signal molecule). This enzyme has been reported to be essential for the survival of Actinobacillus pleuropneumoniae in its natural host. Therefore, it is a potential drug target against A. pleuropneumoniae, an important swine respiratory pathogen causing great economic losses in the pig industry worldwide. In this study, the enzymatic activity determination method was established using the recombinant LuxS of A. pleuropneumoniae. Thirty-five compounds similar to the shape of SRH were screened from the Specs compound library by the software vROCS and were evaluated for LuxS inhibition. Three compounds could inhibit LuxS activity. Two of them were confirmed to be competitive inhibitors and the third one was uncompetitive. All the three compounds displayed inhibitory effects on the growth of A. pleuropneumoniae and two other important swine pathogens, Haemophilis parasuis and Streptococcus suis, with MIC50 values ranging from 11 to 51 μg/ml. No significant cytotoxic effect of the compounds was detected on porcine PK-15 cells at the concentration which showed inhibitory effect on bacterial growth. These results suggest that LuxS is an ideal target to develop antimicrobials for porcine bacterial pathogens. The three LuxS inhibitors identified in this study can be used as lead compounds for drug design.
Friis-Møller, Alice; Christensen, J J; Fussing, V;
Clinical findings in 36 immunosuppressed patients with lower respiratory tract infection or bacteremia with Actinobacillus hominis are described. Animal contact was only recorded for three patients; nine patients died despite appropriate antimicrobial treatment. Although infections with this micr...
Cara sui (care of the self) is a guiding thread in Foucault's later writings on ethics. Following Foucault in that inquiry, we are urged beyond our fairly superficial conceptions of consequences, harms, benefits, and the rights of persons, and led to examine ourselves and try to articulate the sense of life that animates ethical reasoning. The result is a nuanced understanding with links to virtue ethics and post-modern approaches to ethics and subjectivity. The approach I have articulated draws on the phenomenology of Levinas and Heidegger, the Virtue ethics of Baier, and the post-structuralist writing of Michel Foucault. The subject is seen as negotiable, embodied, provisional and able to be transformed in a way that denies essentialism about human beings, their moral status, and the idea of the good. The human being emerges as responsible because, properly, responsive to the context of discourse in which morality becomes articulated. When we import this style of thinking into bioethics we find that it reaches beyond issues of policy or right conduct and allows us to use the biomedical sciences and the clinical world to revise and interrogate our understanding of ourselves and the theoretical foundations of health care ethics.
Bangsborg, Jette Marie; Tvede, M; Skinhøj, P
Haemophilus segnis is a rarely recognised commensal in the oropharynx. We wish to report the first published case of endocarditis caused by H. segnis. The patient, a 76-year-old female did not recover until after 2 courses of ampicillin given for a total of 57 days. In the second course of treatm......Haemophilus segnis is a rarely recognised commensal in the oropharynx. We wish to report the first published case of endocarditis caused by H. segnis. The patient, a 76-year-old female did not recover until after 2 courses of ampicillin given for a total of 57 days. In the second course...
The genetic organization of the gene involved in the capsular polysaccharide (CPS) biosynthesis of Actinobacillus pleuropneumoniae serotype 14 has been determined. The DNA region for the CPS biosynthesis of serotype 14 (cps14) comprised 9 open reading frames, designated as cps14AB1B2B3CDEFG genes, encoding Cps14A to Cps14G protein, respectively. Cps14A was similar to CpsA of A. pleuropneumoniae serotypes 1, 4 and 12; the Cps14B1 and Cps14B2 were similar to CpsB of A. pleuropneumoniae serotypes 1, 4 and 12, suggesting that CPS structure of A. pleuropneumoniae serotype 14 would belong to Group I including A. pleuropneumoniae serotypes 1, 4, 12 and 15. Surprisingly, the overall nucleotide sequence, deduced amino acid sequence, and the genetic organization of the cps14 were nearly identical to those of Actinobacillus suis. This study will provide the molecular basic knowledge for development of diagnostics and vaccine of A. pleuropneumoniae serotype 14.
Hedegaard, J; Okkels, H; Bruun, B; Kilian, M; Mortensen, K K; Nørskov-Lauritsen, N
A 453 bp fragment of infB, the gene encoding translation initiation factor 2, was sequenced and compared from 66 clinical isolates and type strains of Haemophilus species and related bacteria. Analysis of the partial infB sequences obtained suggested that the human isolates dependent on X and V factor, H. influenzae, H. haemolyticus, H. aegyptius and some cryptic genospecies of H. influenzae, were closely related to each other. H. parainfluenzae constituted a heterogeneous group within the boundaries of the genus, whereas H. aphrophilus/paraphrophilus and Actinobacillus actinomycetemcomitans were only remotely related to the type species of the genus Haemophilus H. parahaemolyticus and H. paraphrohaemolyticus took up an intermediary position and may not belong in the genus Haemophilus sensu stricto. Ambiguous results were obtained with seven isolates tentatively identified as H. segnis, which fell into two discrete clusters. The delineation of 'Haemophilus sensu stricto' as suggested by infB analysis supports previous results obtained by DNA hybridization, in contrast to the delineation inferred from 16S rRNA sequence comparison.
Menegueti, Mayra Goncalves; Machado-Viana, Jaciara; Gaspar, Gilberto Gambero; Nicolini, Edson Antonio; Basile-Filho, Anibal; Auxiliadora-Martins, Maria
Haemophilus parainfluenzae, which belongs to the HACEK (Haemophilus ssp, Actinobacillus actinomycetemcomitans, Cardiobacterium hominis, Eikenella corrodens, and Kingella kingae) group, is a rare cause of subacute endocarditis and may lead to ischemic stroke. A 65-year-old female patient previously diagnosed with rheumatic valve disease was submitted to surgical mitral valve repair in 1996. Physical examination did not reveal any murmurs; physical examination of the lungs and abdomen was normal. The patient was admitted to hospital with progressive dyspnea, dry cough, and fever. Transesophageal echocardiogram revealed an approximately 8-mm filamentous image with chaotic motion in the ventricular face of the anterior mitral valve leaflet compatible with vegetation. Treatment with ceftriaxone and gentamicin was initiated. Haemophilus parainfluenzae grew in five blood culture samples. Along the hospital stay, the patient’s level of consciousness decreased, and she was diagnosed with ischemic stroke of cardioembolic etiology. The patient developed septic shock refractory to the prescribed treatment and died 12 days after admission. Even though the patient started being treated for endocarditis before the infectious agent was identified, the prompt use of antimicrobials hindered the growth of Haemophilus parainfluenzae and made its isolation difficult. PMID:27924179
Casin, I; Grimont, F; Grimont, P A
Haemophilus aegyptius should be considered a junior subjective synonym of Haemophilus influenzae. Both nomenspecies are indistinguishable by DNA/DNA hybridization (S1 nuclease method). No single phenotypic test can unambigously separate H. aegyptius from the other biotypes of H. influenzae.
Porath, A; Wanderman, K; Simu, A; Vidne, B; Alkan, M
Endocarditis due to Haemophilus is uncommon. This is the first reported case caused by Haemophilus aegyptius. The course of the disease was complicated by pericarditis, congestive heart failure, and myocardial abscess formation. Surgical removal of the damaged aortic valve was not beneficial. The biologic properties of the organism included urea degradation, absence of indole metabolism, and absence of the enzyme ornithine decarboxylase.
Cristina Román Amigo
Full Text Available Actinobaculum suis is an important agent related to urinary infection in swine females. Due to its fastidious growth characteristics, the isolation of this anaerobic bacterium is difficult, thus impairing the estimation of its prevalence. The purpose of this study was to develop and test a polymerase chain reaction (PCR for the detection and identification of A. suis and then compare these results with traditional isolation methods. Bacterial isolation and PCR were performed on one hundred and ninety-two urine samples from sows and forty-five preputial swabs from boars. The results indicate that this PCR was specific for A. suis, presenting a detection limit between 1.0×101 CFU/mL and 1.0×102 CFU/mL. A. suis frequencies, as measured by PCR, were 8.9% (17/192 in sow urine samples and 82.2% (37/45 in preputial swabs. Assessed using conventional culturing techniques, none of the urine samples were positive for A. suis; however, A. suis was detected in 31.1% (14/45 of the swabs. This PCR technique was shown to be an efficient method for the detection of A. suis in urine and preputial swabs.
Oliveira, S; Galina, L; Pijoan, C
A polymerase chain reaction (PCR) test was developed in order to improve the accuracy and speed of diagnosis of Haemophilus parasuis, an economically important respiratory pathogen that affects swine. The gene sequence of the 16S small subunit ribosomal RNA of H. parasuis (GenBank M75065) was compared with 56 16S sequences of related bacteria, including those frequently isolated from pig tissues. Two species-specific primers were designed: HPS forward and HPS reverse. The predicted size of the amplified PCR product was 821 bp. The PCR test could detect a minimum of 102 bacteria and 0.69 pg of DNA. Thirty-one H. parasuis isolates, including 12 different serovars and 19 field isolates, were positive using the PCR test. No amplification was observed when the test was run using DNA from 15 other bacterial species commonly isolated from swine tissues. A weak band was observed when the PCR test was performed using Actinobacillus indolicus DNA as template. Clinical samples tested by PCR included tissues and swabs from 5 animals naturally infected with H. parasuis and 1 experimentally infected animal. The PCR was positive in 26 of 30 clinical samples. Four samples showed weak bands, and these results were not considered positive. Haemophilus parasuis was isolated from 18 of 30 of these samples. Tissues from specific pathogen-free (SPF) pigs and from unrelated species were negative for H. parasuis isolation and PCR. The developed PCR was successfully used in the diagnosis of H. parasuis infection, especially when compared with traditional microbiology techniques.
Full Text Available The aims of the present study were to assess the prevalence of Chlamydia suis in an Italian pig herd, determine the tetracycline susceptibility of C. suis isolates, and evaluate tet(C and tetR(C gene expression. Conjunctival swabs from 20 pigs were tested for C. suis by real-time polymerase chain reaction, and 55% (11 were positive. C. suis was then isolated from 11 conjunctival swabs resampled from the same herd. All positive samples and isolates were positive for the tet(C resistance gene. The in vitro susceptibility to tetracycline of the C. suis isolates showed MIC values ranging from 0.5 to 4 μg/mL. Tet(C and tetR(C transcripts were found in all the isolates, cultured both in the absence and presence of tetracycline. This contrasts with other Gram-negative bacteria in which both genes are repressed in the absence of the drug. Further investigation into tet gene regulation in C. suis is needed.
Donati, Manuela; Balboni, Andrea; Laroucau, Karine; Aaziz, Rachid; Vorimore, Fabien; Borel, Nicole; Morandi, Federico; Vecchio Nepita, Edoardo; Di Francesco, Antonietta
The aims of the present study were to assess the prevalence of Chlamydia suis in an Italian pig herd, determine the tetracycline susceptibility of C. suis isolates, and evaluate tet(C) and tetR(C) gene expression. Conjunctival swabs from 20 pigs were tested for C. suis by real-time polymerase chain reaction, and 55% (11) were positive. C. suis was then isolated from 11 conjunctival swabs resampled from the same herd. All positive samples and isolates were positive for the tet(C) resistance gene. The in vitro susceptibility to tetracycline of the C. suis isolates showed MIC values ranging from 0.5 to 4 μg/mL. Tet(C) and tetR(C) transcripts were found in all the isolates, cultured both in the absence and presence of tetracycline. This contrasts with other Gram-negative bacteria in which both genes are repressed in the absence of the drug. Further investigation into tet gene regulation in C. suis is needed.
Zhou, L.; Jones, S.C.P.; Angen, Øystein
Serotypes 3 and 8 of Actinobacillus pleuropneumoniae, the aetiological agent of porcine pleuropneumonia, have been reported to predominate in the UK. Direct serotyping of isolates of the organism is typically determined by the immunological reactivity of rabbit serum to its surface polisaccharides...... of A pleuropneumoniae and 121 strains of other organisms, including all the major respiratory bacterial pathogens of pigs. The test was highly specific and sensitive and should be useful for differentiating strains of serotypes 3, 6, and 8, and in seroprevalence and epidemiological surveys in regions where serotype 3...
Kleinfelder, JW; Mueller, RF; Lange, DE
Background: Periodontitis patients harboring Actinobacillus actinmycetemcomitans (Aa) are prime candidates for systemic antibiotic therapy. Besides tetracycline and the combination of metronidazole and amoxicillin the fluoroquinolones are also believed to have antibacterial activity against Aa. The
Kleinfelder, JW; Mueller, RF; Lange, DE
Background: Periodontitis patients harboring Actinobacillus actinmycetemcomitans (Aa) are prime candidates for systemic antibiotic therapy. Besides tetracycline and the combination of metronidazole and amoxicillin the fluoroquinolones are also believed to have antibacterial activity against Aa. The
Rossi, Ciro C; Pereira, Monalessa F; Langford, Paul R; Bazzolli, Denise M S
Bacterial respiratory diseases are responsible for considerable mortality, morbidity and economic losses in the swine industry. Actinobacillus pleuropneumoniae, the causative agent of porcine pleuropneumonia, is one of the most important disease agents, but its identification and surveillance can be impaired by the existence of many other related bacteria in normal swine microbiota. In this work, we have evaluated a BOX-A1R-based repetitive extragenic palindromic-PCR (BOX-PCR) sequence characterised amplified region (SCAR) marker for the specific identification of A. pleuropneumoniae and its use in a multiplex PCR to detect additionally Haemophilus parasuis and Pasteurella multocida, two other major respiratory pathogens of pigs that are members of the family Pasteurellaceae. PCRs based on the BOX-SCAR fragment developed were rapid, sensitive and differentiated A. pleuropneumoniae from all swine-related members of the Pasteurellaceae family tested. Single and multiplex BOX-SCAR fragment-based PCRs can be used to identify A. pleuropneumoniae from other bacterial swine pathogens and will be useful in surveillance and epidemiological studies. © 2014 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.
Gould, L; Gopalaswamy, C; Kim, B S; Patel, C; Freiberg, K
Actinobacillus actinomycetemcomitans is a very uncommon cause of infectious endocarditis. The organism was first described in 1912. Thjotta and Sydnes reported its isolation in pure culture from a long standing abscess which had developed after tooth extraction. Subsequently this organism was found to be part of the normal flora, and the organism was defined as a slow growing, fastidious gram negative bacillus. Carbon dioxide is essential for the growth of A. actinomycetemcomitans. Approximately 50 cases of endocarditis due to A. actinomycetemcomitans have been reported since the first case reported in 1964. The purpose of this report is to document a case of endocarditis due to A. actinomycetemcomitans and to stress the value of the echocardiogram in the assessment of patients with endocarditis.
Carmalt, J L; Baptiste, K E; Chirino-Trejo, J M
A 10-year-old pregnant Norwegian Fjord horse was examined for gross swelling of the muzzle of 2 years' duration. Examination of biopsy specimens revealed diffuse dermal fibrosis, micropustule formation, and vascular thrombosis; large numbers of Actinobacillus lignieresii were isolated in pure culture. Prolonged treatment with i.v. administration of sodium iodide and oral administration of trimethoprim-sulfamethoxazole caused regression of the swelling and did not induce abortion. A 5-month-old American Paint filly was examined for swelling in the udder region. Bacteriologic culture of purulent material obtained from the left teat revealed A lignieresii. Treatment with oral administration of rifampin and trimethoprim-sulfamethoxazole resulted in complete resolution of clinical signs. To the authors' knowledge, these findings represent the first report of mastitis and chronic nasal cellulitis caused by A lignieresii infection in horses.
Chabot-Roy, Geneviève; Willson, Philip; Segura, Mariela; Lacouture, Sonia; Gottschalk, Marcelo
Streptococcus suis serotype 2 is an important swine pathogen responsible for diverse infections, mainly meningitis. Virulence factors and the pathogenesis of infection are not well understood. Neutrophils may play an important role in the pathogenesis of infection given that infiltration by neutrophils and mononuclear cells are frequently observed in lesions caused by S. suis. The objective of this work was to study the interactions between S. suis serotype 2 and porcine neutrophils. Results showed that suilysin is toxic to neutrophils and this could help S. suis evade innate immunity. Moreover, suilysin appears to affect complement-dependent killing by decreasing the opsonization of S. suis and the bactericidal capacity of neutrophils. Our results confirm that capsule polysaccharide protects S. suis against killing and phagocytosis by neutrophils. We also showed that the presence of specific IgG against S. suis serotype 2 promoted killing by neutrophils, indicating that the induction of a strong humoral response is beneficial for clearance of this pathogen.
O. De Smidt
Full Text Available The region involved in export of the capsule polysaccharides to the cell surface of Haemophilus paragallinarum was cloned and the genetic organisation determined. Degenerate primers designed from sequence alignment of the capsule transport genes of Haemophilus influenzae, Pasteurella multocida and Actinobacillus pleuropneumoniae were used to amplify a 2.6 kb fragment containing a segment of the H. paragallinarum capsule transport gene locus. This fragment was used as a digoxigenin labelled probe to isolate the complete H. paragallinarum capsule transport gene locus from genomic DNA. The sequence of the cloned DNA was determined and analysis revealed the presence of four genes, each showing high homology with known capsule transport genes. The four genes were designated hctA, B, C and D (for H. paragallinarum capsule transport genes and the predicted products of these genes likely encode an ATP-dependent export system responsible for transport of the capsule polysaccharides to the cell surface, possibly a member of a super family designated ABC (ATP-binding cassette transporters.
Bonifait, Laetitia; Veillette, Marc; Létourneau, Valérie; Grenier, Daniel; Duchaine, Caroline
Streptococcus suis is an important swine pathogen that can cause septicemia, meningitis, and pneumonia. Also recognized as an emerging zoonotic agent, it is responsible for outbreaks of human infections in Asian countries. Serotype 2 is the predominant isolate from diseased animals and humans. The aerosolization of S. suis in the air of swine confinement buildings (SCB) was studied. The presence of S. suis in bioaerosols was monitored in SCB where cases of infection had been reported and in healthy SCB without reported infections. Using a quantitative-PCR (qPCR) method, we determined the total number of bacteria (1 × 10(8) to 2 × 10(8) airborne/m(3)), total number of S. suis bacteria (4 × 10(5) to 10 × 10(5) airborne/m(3)), and number of S. suis serotype 2 and 1/2 bacteria (1 × 10(3) to 30 × 10(3) airborne/m(3)) present in the air. S. suis serotypes 2 and 1/2 were detected in the air of all growing/finishing SCB that had documented cases of S. suis infection and in 50% of healthy SCB. The total number of bacteria and total numbers of S. suis and S. suis serotype 2 and 1/2 bacteria were monitored in one positive SCB during a 5-week period, and it was shown that the aerosolized S. suis serotypes 2 and 1/2 remain airborne for a prolonged period. When the effect of aerosolization on S. suis was observed, the percentage of intact S. suis bacteria (showing cell membrane integrity) in the air might have been up to 13%. Finally S. suis was found in nasal swabs from 14 out of 21 healthy finishing-SCB workers, suggesting significant exposure to the pathogen. This report provides a better understanding of the aerosolization, prevalence, and persistence of S. suis in SCB.
Ricardo M. Pereira
Full Text Available OBJETIVO: Descrever o caso de uma criança com endocardite infecciosa causada por Haemophilus aphrophilus. DESCRIÇÃO: Menino com febre e calafrios há 20 dias. À internação, apresentava-se febril, descorado e sem sinais de instabilidade hemodinâmica; à ausculta cardíaca, tinha sopro holosistólico em foco mitral. Os exames laboratoriais identificaram anemia (hemoglobina = 9,14 g/dL, leucócitos totais de 11.920 mm³, plaquetas de 250.000 mm³, velocidade de sedimentação das hemácias e proteína C reativa elevadas. O ecocardiograma revelou imagem em válvula mitral, sugestiva de vegetação. Com a hipótese de endocardite, foi iniciada antibioticoterapia com penicilina cristalina (200.000 UI/kg/dia associada à gentamicina (4 mg/kg/dia. No terceiro dia de tratamento, foi identificado Haemophilus aphrophilus em hemoculturas, sendo então trocado o esquema antibiótico para ceftriaxona (100 mg/kg/dia. No 20º dia de internação, encontrava-se pálido, mas sem febre e sem outras queixas. Os exames mostravam hemoglobina = 7,0 g/dL, leucócitos = 2.190 mm³, plaquetas = 98.000 mm³, razão normatizada internacional = 1,95 e R = 1,89. Foi feita hipótese de reação adversa ao ceftriaxona, que foi substituído por ciprofloxacina, 20 mg/kg/dia, até completar 6 semanas de tratamento. Após 72 horas da troca, houve normalização dos exames. Durante seguimento ambulatorial, apresentou insuficiência mitral grave, sendo submetido a troca de válvula por prótese metálica 9 meses após quadro agudo. Há 3 anos encontra-se bem, em acompanhamento ambulatorial. COMENTÁRIOS: É rara a identificação de agentes do grupo HACEK (Haemophilus ssp, Actinobacillus actinomycetemcomitans, Cardiobacterium hominis, Eikenella corrodens e Kingella kingae em crianças com endocardite infecciosa. O caso apresentado, sem fatores de risco relacionados a esses agentes, reafirma a necessidade de tentar sempre identificar o agente etiológico das endocardites para
Opriessnig, Tanja; Hemann, Michelle; Johnson, John K; Heinen, Sheila; Giménez-Lirola, Luis G; O'Neill, Kevin C; Hoang, Hai; Yoon, Kyoung-Jin; Gottschalk, Marcelo; Halbur, Patrick G
Accurate diagnosis of exposure to Actinobacillus pleuropneumoniae is important for maintaining negative farms. In the present study, the ability of a dual-plate complement fixation (CF) assay and 3 commercially available enzyme-linked immunosorbent assays (ELISAs; quad-plate ELISA-1, single-plate ELISA-2, and single-plate ELISA-3) in detecting serological evidence of A. pleuropneumoniae exposure was compared using serum samples of experimentally infected or vaccinated pigs, or field samples from the United States. Forty-two pigs were divided into groups of 2 pigs and were inoculated with 1 of 15 A. pleuropneumoniae strains representing all known serovars of A. pleuropneumoniae, or with Actinobacillus suis, or were vaccinated with a bacterin containing A. pleuropneumoniae serovar 1, 3, 5, or 7. Serum samples collected at the day of inoculation or vaccination and 7, 14, 21, and 28 days later were used to compare the assays. On samples from experimentally infected pigs, the dual-plate CF assay, quad-plate ELISA-1, single-plate ELISA-2, and single-plate ELISA-3 had sensitivities of 0.46, 0.74, 0.13, and 0.13 and specificities of 0.90, 1.0, 1.0, and 1.0, respectively. Vaccinated pigs were identified only by the dual-plate CF assay and the quad-plate ELISA-1. In addition, 90 serum samples with unknown A. pleuropneumoniae exposure collected under field conditions were tested with all assays. The agreement of the 4 assays on field samples was slight to fair. While several assays are available for demonstration of A. pleuropneumoniae exposure, differences in assay targets complicate test choices. Decisions on which assay or combination of assays to use depend on the specific reasons for running the assays.
Merino, M; Biberstein, E L
The growth factor needs of Haemophilus somnus, which have not been defined to date, were found to be provided by 1% IsoVitaleX (IVX; BBL Microbiology Systems) in tryptose broth. Some growth, however, occurred in unsupplemented tryptose broth. Of the ingredients of IVX, cocarboxylase was found to stimulate growth to about the same degree as the total supplement. Cocarboxylase was without direct effect in 2% peptone broth, which supported no growth of 25 H. somnus strains until supplemented wit...
Full Text Available Abstract Helicobacter (H. suis is a porcine and human gastric pathogen. Previous studies in mice showed that an H. suis infection does not result in protective immunity, whereas immunization with H. suis whole-cell lysate (lysate protects against a subsequent experimental infection. Therefore, two-dimensional gel electrophoresis of H. suis proteins was performed followed by immunoblotting with pooled sera from H. suis- infected mice or mice immunized with lysate. Weak reactivity against H. suis proteins was observed in post-infection sera. Sera from lysate-immunized mice, however, showed immunoreactivity against a total of 19 protein spots which were identified using LC-MS/MS. The H. suis urease subunit B (UreB showed most pronounced reactivity against sera from lysate-immunized mice and was not detected with sera from infected mice. None of the pooled sera detected H. suis neutrophil-activating protein A (NapA. The protective efficacy of intranasal vaccination of BALB/c mice with H. suis UreB and NapA, both recombinantly expressed in Escherichia coli (rUreB and rNapA, respectively, was compared with that of H. suis lysate. All vaccines contained choleratoxin as adjuvant. Immunization of mice with rUreB and lysate induced a significant reduction of H. suis colonization compared to non-vaccinated H. suis-infected controls, whereas rNapA had no significant protective effect. Probably, a combination of local Th1 and Th17 responses, complemented by antibody responses play a role in the protective immunity against H. suis infections.
acquired after brucellosis is characterized by fever, chills, malaise, ingestion of foodstuffs, especially unpasteurized dairy and a chronic course...synthesis of OMP genes of B. suis. Seven OMP genes of the samples were incubated with 1:2000 secondary goat B, suis were PCR synthesized using...antibody and protects rhesus macaques from infectious brucellosis induced by subsequent aerosolFig. 3. PCR detection of pET-DEST42-B, suis OMP genes
Martel, A Y; Sottnek, F O; Thomas, M L; Albritton, W L
Two hundred and nine strains of Haemophilus influenzae and Haemophilus aegyptius were screened for trooleandomycin susceptibility. Four strains were shown to be sensitive to the drug. Of these four, two were Haemophilus aegyptius (ATCC 11116, NCTC 8134), and the other two were Haemophilus influenzae biotype I (1-605) and IV (80-212. One strain of Haemophilus aegyptius (NCTC 8135) was resistant to trooleandomycin. Restriction enzyme assays and DNA homology were carried out to establish relationships between the strains. It is concluded that trooleandomycin susceptibility has no taxonomic value to differentiate between Haemophilus aegyptius and biotype III Haemophilus influenzae.
James N. Stanford
Full Text Available Sui, an indigenous minority language of southwest China, has an elaborate system of adjective intensification. Adjectives are intensified with word-specific, bound morphemes that usually either rhyme with the base or alliterate with the base. Stanford (2007 notes morpho-phonological patterns that suggest reduplication, rhyme, alliteration, The Emergence of the Unmarked (McCarthy & Prince 1994, Yip 2001, identity avoidance, and “Copy But Don’t Repeat” (Kennard 2004. However, the adjective intensifiers defy a simple, fully predictable explanation in such terms; the intensifier lexicon may be best described as “patterned variety,” a case of lexicalized poetry or a poeticized lexicon. Word formation is guided by general patterns, but each specific intensifier may vary within those overall guidelines. Many adjectives have multiple intensifiers that bear subtle semantic and pragmatic distinctions. The current paper serves as a complement to Stanford (2007 by providing a detailed lexicon of the Sui adjective intensifiers for future reference and further analysis. This lexicon is based on the author’s fieldwork and represents the first detailed account of Sui adjective intensifiers for the wider linguistic community.
Donati, Manuela; Di Paolo, Maria; Favaroni, Alison; Aldini, Rita; Di Francesco, Antonietta; Ostanello, Fabio; Biondi, Roberta; Cremonini, Eleonora; Ginocchietti, Laura; Cevenini, Roberto
A mouse model for Chlamydia suis genital infection was developed. Ninety-nine mice were randomly divided into three groups and intravaginally inoculated with chlamydia: 45 mice (group 1) received C. suis purified elementary bodies (EBs), 27 (group 2) were inoculated with C. trachomatis genotype E EBs and 27 mice (group 3) with C. trachomatis genotype F EBs. Additionally, 10 mice were used as a negative control. At seven days post-infection (dpi) secretory anti-C. suis IgA were recovered from vaginal swabs of all C. suis inoculated mice. Chlamydia suis was isolated from 93, 84, 71 and 33% vaginal swabs at 3, 5, 7 and 12 dpi. Chlamydia trachomatis genotype E and F were isolated from 100% vaginal swabs up to 7 dpi and from 61 and 72%, respectively, at 12 dpi. Viable C. suis and C. trachomatis organisms were isolated from uterus and tubes up to 16 and 28 dpi, respectively. The results of the present study show the susceptibility of mice to intravaginal inoculation with C. suis. A more rapid course and resolution of C. suis infection, in comparison to C. trachomatis, was highlighted. The mouse model could be useful for comparative investigations involving C. suis and C. trachomatis species.
Giglio, C; Aránguiz, V; Giglio, M S; Fernández, A
Actinobacillus actinomycetemcomitans (AA), is a cocobacillus thin and small, non motile, uncapsulate and capnophilic. AA, is: one of the species encountered in the mouth's comensal flora being able to be isolated in gingival crevices culture and oral mucosa in a 20% of the healthy population. An important number of pathogenic factors make it well equipped, to protect itself from host's defense mechanisms, and to destroy the periodontal tissue. Between the most important we find lipopolisacarides and leucotoxines which promote tisular invasion and destructive qualities of this microorganism. Since 1912, there are numerous reports of infectious process associated to it, between which we find: endocarditis in native and prothesic valve, soft tissues abscess, pneumonia, brain's abscess, urethritis, vertebral osteomielitis, thyroid's abscess, pericarditis and periodontal juvenile illness, being this one in which its isolation is more frequent. In vitro, AA is very susceptible to tetracicline. This antibiotic reaches high concentrations in gingival crevices, has significant affinity to the alveolar bone and contributes to protect the collagen. These special feature make them the election drug in periodontal disease produced by this microorganism.
Casin, I.M.; Sanson-Le Pors, M.J.; Gorce, M.F.; Ortenberg, M.; Perol, Y. (Universite Paris - 7, Hopital Saint-Louis, 75 - Paris (France))
The enzymatic activities of two reference strains of Haemophilus ducreyi and thirty clinical isolates were investigated by conventional biochemical tests and the API-ZYM test kit system which included 97 synthetic substrates. No strains converted ..delta..-aminolevulinic acid to porphyrins, but they all reduced nitrates to nitrites. All strains possessed aminopeptidase activity against ..beta..-naphthylamide derivatives of L-alanine, L-arginine, L-glutamine, glycine, L-leucine, L-lysine and L-serine. No trypsin or chymotrypsin-like activities were detected. All strains had phosphatase activity with broad pH range, and phosphoamidase activity. No glycosidase was detected by the substrates tested.
Mann, J M; Rheins, M S
Extracts possessing the capacity to hemagglutinate normal human erythrocytes were recovered from Haemophilus aegyptius by treatment with either diethylene glycol or acetone. Antisera prepared against these extracts or the unextracted bacterial cell inhibited hemagglutination by homologous and heterologous antigens. Microgel diffusions indicated the presence of identical components in each extract as expressed by lines of identity between antisera to each fraction. The hemagglutinin was identified as a lipopolysaccharide, 42% lipid and 57% carbohydrate. The determination of 6% phosphorus in the lipid fraction identified it as containing phospholipid.
Núbia Resende de Macêdo
Full Text Available A maioria dos estudos epidemiológicos envolvendo Haemophilus parasuis isolados de rebanhos suínos brasileiros se baseia em sorotipagem. Entretanto, uma alta porcentagem de amostras não é sorotipável. Técnicas moleculares têm sido utilizadas com sucesso para caracterizar a diversidade dos isolados de H. parasuis e a epidemiologia das infecções por esse agente dentro e entre rebanhos. Esta revisão enfoca aspectos gerais da infecção por H. parasuis, principalmente em relação às técnicas de epidemiologia molecular.The majority of epidemiological studies involving Haemophilus parasuis from Brazilian herds are based on serotyping. However, a high percentage of isolates are non-typable. Recently, molecular-based techniques were successfully used to characterize the diversity of H. parasuis isolates and the epidemiology of H. parasuis infections within and among herds. This review tackles general aspects of H. parasuis infection, mainly regarding to techniques of molecular epidemiology.
Boekema, B.K.H.L. (Bouke Karel Hendrik Laurentius)
Actinobacillus pleuropneumoniae causes porcine pleuropneumonia, a disease that occurs world-wide and affects growing pigs of all ages. Infection of pigs with A. pleuropneumoniae can result in high morbidity and mortality. The present work contributes to the understanding of the pathogenesis of A.
Carlone, G M; Sottnek, F O; Plikaytis, B. D.
Haemophilus aegyptius and Haemophilus influenzae biotype III are morphologically and biochemically similar; however, their outer membrane protein (Sarkosyl insoluble) profiles are distinct. Of 18 strains of H. aegyptius examined, 15 had a type 1 protein profile, and 3 had a type 2 profile, whereas the 5 strains of H. influenzae biotype III examined had three other protein profile types. All Haemophilus strains examined had 31- and 76-kilodalton (kDa) proteins and minor proteins with molecular...
Wichgers, P.J.; Weeghel, van C.; Rebel, J.M.J.; Smits, M.A.; Putten, van J.P.M.; Smith, H.E.
Background Streptococcus suis is an important infectious agent for pigs and occasionally for humans. The host innate immune system plays a key role in preventing and eliminating S. suis infections. One important constituent of the innate immune system is the protein lysozyme, which is present in a v
Cardoso, Marta Pessoa; Pasternak, Jacyr; Giglio, Alfredo Elias; Casagrande, Rejane Rimazza Dalberto; Troster, Eduardo Juan
With the decline in the rate of infections caused by Haemophilus influenzae serotype b since the widespread vaccination, non-b serotypes should be considered as potential pathogenic agents in children with invasive disease younger than 5 years old. We report the case of an immunocompetent 1-year-old boy with Haemophilus influenzae type f meningitis. The agent was identified in cerebrospinal fluid and blood cultures. Serotyping was performed by tests using polyclonal sera and confirmed by polymerase chain reaction. All Haemophilus influenzae isolates associated with invasive disease should be serotyped and notified as a way to evaluate the changes and trends in serotype distribution of this disease.
Mori A., Lorena; Calle E., Sonia; Pinto J., Chris; Torres A., Marlon; Falcon P., Nestor; Morales C., Siever
El objetivo del estudio fue determinar la frecuencia de anticuerpos contra la toxina ApxIV de Actinobacillus pleuropneumoniae, causante de pleuroneumonia porcina en 10 granjas porcinas tecnificadas...
Bossé, Janine T.; Li, Yanwen; Fernandez Crespo, Roberto; Chaudhuri, Roy R.; Rogers, Jon; Holden, Matthew T. G.; Maskell, Duncan J.; Tucker, Alexander W.; Wren, Brendan W.; Rycroft, Andrew N.; Langford, Paul R.
ICEApl1 was identified in the whole genome sequence of MIDG2331, a tetracycline-resistant (MIC = 8 mg/L) serovar 8 clinical isolate of Actinobacillus pleuropneumoniae, the causative agent of porcine pleuropneumonia. PCR amplification of virB4, one of the core genes involved in conjugation, was used to identify other A. pleuropneumoniae isolates potentially carrying ICEApl1. MICs for tetracycline were determined for virB4 positive isolates, and shotgun whole genome sequence analysis was used to confirm presence of the complete ICEApl1. The sequence of ICEApl1 is 56083 bp long and contains 67 genes including a Tn10 element encoding tetracycline resistance. Comparative sequence analysis was performed with similar integrative conjugative elements (ICEs) found in other members of the Pasteurellaceae. ICEApl1 is most similar to the 59393 bp ICEHin1056, from Haemophilus influenzae strain 1056. Although initially identified only in serovar 8 isolates of A. pleuropneumoniae (31 from the UK and 1 from Cyprus), conjugal transfer of ICEApl1 to representative isolates of other serovars was confirmed. All isolates carrying ICEApl1 had a MIC for tetracycline of 8 mg/L. This is, to our knowledge, the first description of an ICE in A. pleuropneumoniae, and the first report of a member of the ICEHin1056 subfamily in a non-human pathogen. ICEApl1 confers resistance to tetracycline, currently one of the more commonly used antibiotics for treatment and control of porcine pleuropneumonia. PMID:27379024
Janine T Bosse
Full Text Available ICEApl1 was identified in the whole genome sequence of MIDG2331, a tetracycline-resistant (MIC = 8 mg/L serovar 8 clinical isolate of Actinobacillus pleuropneumoniae, the causative agent of porcine pleuropneumonia. PCR amplification of virB4, one of the core genes involved in conjugation, was used to identify other A. pleuropneumoniae isolates potentially carrying ICEApl1. MICs for tetracycline were determined for virB4 positive isolates, and shotgun whole genome sequence analysis was used to confirm presence of the complete ICEApl1. The sequence of ICEApl1 is 56083 bp long and contains 67 genes including a Tn10 element encoding tetracycline resistance. Comparative sequence analysis was performed with similar integrative conjugative elements (ICEs found in other members of the Pasteurellaceae. ICEApl1 is most similar to the 59393 bp ICEHin1056, from Haemophilus influenzae strain 1056. Although initially identified only in serovar 8 isolates of A. pleuropneumoniae (31 from the UK and 1 from Cyprus, conjugal transfer of ICEApl1 to representative isolates of other serovars was confirmed. All isolates carrying ICEApl1 had a MIC for tetracycline of 8 mg/L. This is, to our knowledge, the first description of an ICE in A. pleuropneumoniae, and the first report of a member of the ICEHin1056 subfamily in a non-human pathogen. ICEApl1 confers resistance to tetracycline, currently one of the more commonly used antibiotics for treatment and control of porcine pleuropneumonia.
U.S. Department of Health & Human Services — NNDSS - Table II. Giardiasis to Haemophilus influenza - 2017. In this Table, provisional cases of selected notifiable diseases (â¥1,000 cases reported during the...
U.S. Department of Health & Human Services — NNDSS - Table II. Giardiasis to Haemophilus influenza - 2014. In this Table, all conditions with a 5-year average annual national total of more than or equals 1,000...
U.S. Department of Health & Human Services — NNDSS - Table II. Giardiasis to Haemophilus influenza - 2015.In this Table, provisional cases of selected notifiable diseases (â¥1,000 cases reported during the...
U.S. Department of Health & Human Services — NNDSS - Table II. Giardiasis to Haemophilus influenza - 2016. In this Table, provisional* cases of selectedâ notifiable diseases (â¥1,000 cases reported during the...
DETECTION AND TRANSMISSION OF EXTRACELLULAR FACTOR PRODUCING STREPTOCOCCUS SUIS SEROTYPE 2 STRAINS IN PIGS INTRODUCTION Streptococcus suis (S.suis) has been implicated in the etiology of many diseases among which meningitis in pigs. The virulent extracellular factor-positive strains of S.suis
DETECTION AND TRANSMISSION OF EXTRACELLULAR FACTOR PRODUCING STREPTOCOCCUS SUIS SEROTYPE 2 STRAINS IN PIGS INTRODUCTION Streptococcus suis (S.suis) has been implicated in the etiology of many diseases among which meningitis in pigs. The virulent extracellular factor-positive strains of S.suis seroty
Pablo Guadarrama González
Full Text Available El positivismo fue asumido y cultivado en Latinoamérica de forma sui generis como una filosofía optimista llena de confianza en el hombre, en la capacidad creativa de su pensamiento, en la cultura, la educación, la ciencia, el progreso y el desarrollo industrial. Aliado al liberalismo y a la defensa de la democracia sus ideas resultaban muy avanzadas para los países latinoamericanos, recién liberados en su mayoría del colonialismo español y enfrascados entonces en profundas luchas entre las oligarquías retrogradas y la naciente burguesía nacional. Las ideas filosóficas y educativas de Hostos ponen de manifiesto la riqueza alcanzada por el pensamiento latinoamericano en el siglo XIX que aunque compartió algunas posiciones con el krausismo y el positivismo no se dejó arrastrar de forma unilateral por estas corrientes y supo aprovechar los elementos de valor contenidos especialmente en el positivismo que supo asumir de modo sui generis como la mayoría de los intelectuales latinoamericanos de esa época que se identificaron con él en correspondencia con una praxis educativa y política beneficiosa a los pueblos de América Latina.
Zhang, Bowen; Kunde, Dale; Tristram, Stephen
The commensal Haemophilus haemolyticus is difficult to differentiate from the respiratory pathogen Haemophilus influenzae using phenotypic tests. In a study that used molecular tests to retrospectively identify 447 phenotypically identified H. influenzae isolates from diagnostic specimens in Australia, only 7 (1.5%) H. haemolyticus were identified.
González-Beiras, Camila; Marks, Michael; Chen, Cheng Y; Roberts, Sally; Mitjà, Oriol
The global epidemiology of Haemophilus ducreyi infections is poorly documented because of difficulties in confirming microbiological diagnoses. We evaluated published data on the proportion of genital and nongenital skin ulcers caused by H. ducreyi before and after introduction of syndromic management for genital ulcer disease (GUD). Before 2000, the proportion of GUD caused by H. ducreyi ranged from 0.0% to 69.0% (35 studies in 25 countries). After 2000, the proportion ranged from 0.0% to 15.0% (14 studies in 13 countries). In contrast, H. ducreyi has been recently identified as a causative agent of skin ulcers in children in the tropical regions; proportions ranged from 9.0% to 60.0% (6 studies in 4 countries). We conclude that, although there has been a sustained reduction in the proportion of GUD caused by H. ducreyi, this bacterium is increasingly recognized as a major cause of nongenital cutaneous ulcers.
Gomez-Lus, R; Vergara, Y
From September 1, 1990 to December 31, 1993 a total of 425 Haemophilus influenzae strains from clinical specimens were isolated in the Microbiology Laboratory of the Zaragoza University Hospital. Of these strains, 16 (33.33%) were resistant to kanamycin, neomycin, paromomycin, lividomycin and streptomycin. Demonstration of APH (3')-I activity by the phosphocellulose paper binding assay, based on the incorporation of radiolabel into lividomycin was sixfold greater than into butirosin. Two DNA probes were prepared to screen for the genes encoding APH(3') activity in kanamycin-resistant H. influenzae. Homology was observed between the aphA1 DNA probe and total cellular DNA from all 16 APH(3')-I producers. On the other hand, streptomycin-resistance was not through metabolic modification of the antibiotic.
Full Text Available Streptococcus suis is an important swine pathogen and an emerging zoonotic agent of septicemia and meningitis. Knowledge on host immune responses towards S. suis, and strategies used by this pathogen for subversion of these responses is scarce. The objective of this study was to identify the immune receptors involved in S. suis recognition by dendritic cells (DCs. Production of cytokines and expression of co-stimulatory molecules by DCs were shown to strongly rely on MyD88-dependent signaling pathways, suggesting that DCs recognize S. suis and become activated mostly through Toll-like receptor (TLR signaling. Supporting this fact, TLR2(-/- DCs were severely impaired in the release of several cytokines and the surface expression of CD86 and MHC-II. The release of IL-12p70 and CXC10, and the expression of CD40 were found to depend on signaling by both TLR2 and TLR9. The release of IL-23 and CXCL1 were partially dependent on NOD2. Finally, despite the fact that MyD88 signaling was crucial for DC activation and maturation, MyD88-dependent pathways were not implicated in S. suis internalization by DCs. This first study on receptors involved in DC activation by S. suis suggests a major involvement of MyD88 signaling pathways, mainly (but not exclusively through TLR2. A multimodal recognition involving a combination of different receptors seems essential for DC effective response to S. suis.
... derived from clinical specimens. The identification aids in the diagnosis of diseases caused by bacteria belonging to the genus Haemophilus and provides epidemiological information on diseases cause by these microorganisms. Diseases most often caused by Haemophilus spp. include pneumonia, pharyngitis,...
The whipworm of swine, Trichuris suis, is a gastrointestinal nematode that lives attached to the large intestinal mucosa of its host. Except for when infection levels are high, this parasite rarely causes disease in pigs. Nevertheless, increased interest in T. suis has arisen from studies...... demonstrating the potential use of its eggs as immunomodulators, treating patients suffering from inflammatory bowel disease and possibly other autoimmune diseases. The immune response induced by T. suis in its host and particularly, the resulting expulsion of worms is the focus of this thesis. Whipworms...
Stenbaek, E.I.; HovindHaugen, K.
Until now 12 serotypes of Actinobacillus pleuropneumoniae have been recognized. The specificity of the serotypes reside in the carbohydrate composition of the capsular polysaccharides and lipopolysaccharides (LPS). The LPS of A. pleuropneumoniae serotype 2 is a smooth type LPS with O-chains of li......Until now 12 serotypes of Actinobacillus pleuropneumoniae have been recognized. The specificity of the serotypes reside in the carbohydrate composition of the capsular polysaccharides and lipopolysaccharides (LPS). The LPS of A. pleuropneumoniae serotype 2 is a smooth type LPS with O......-chains of linear repeating pentasaccharide units with an O-acetyl group linked to a glucose unit. A monoclonal antibody (MAb 102-G02) directed against A. pleuropneumoniae serotype 2 was characterized in enzyme linked immunosorbent assay (ELISA) and in sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS...
Zhan, Bujie; Angen, Øystein; Hedegaard, Jakob
Actinobacillus pleuropneumoniae is a bacterial pathogen that causes highly contagious respiratory infection in pigs and has a serious impact on the production economy and animal welfare. As clear differences in virulence between serotypes have been observed, the genetic basis should be investigated...... at the genomic level. Here, we present the draft genome sequences of the A. pleuropneumoniae serotypes 2 (strain 4226) and 6 (strain Femo)....
Full Text Available Aggregatibacter (Actinobacillus actinomycetemcomitans is a capnoic gram negative coccobacilli known to produce juvenile periodontitis. This organism was isolated in pure culture from an unusual case of osteomyelitis of the mandible. The patient was treated with tetracycline, which is the drug of choice for A. actinomycetemcomitans and the clinical response improved. From our limited review of the literature, it appears that this is the first case of osteomyelitis due to A.actinomycetemcomitans reported in India.
Miyasaki, K T; Wilson, M E; Brunetti, A J; Genco, R J
Actinobacillus actinomycetemcomitans is a facultative gram-negative microorganism which has been implicated as an etiologic agent in localized juvenile periodontitis and in subacute bacterial endocarditis and abscesses. Although resistant to serum bactericidal action and to oxidant injury mediated by superoxide anion (O2-) and hydrogen peroxide (H2O2), this organism is sensitive to killing by the myeloperoxidase-hydrogen peroxide-chloride system (K.T. Miyasaki, M.E. Wilson, and R.J. Genco, In...
Aalbæk, Bent; Østergaard, Stine; Buhl, Rikke;
Microbiological and pathological data from a case of equine valvular endocarditis are reported. Limited information is available on the pathogenic potential of equine Actinobacillus species as several strains originate from apparently healthy horses. After the establishment of two subspecies within...... this species, this seems to be the first report of an etiological association between A. equuli subsp. equuli and equine endocarditis. Furthermore, new information on some phenotypical characteristics of this subspecies are reported, compared to previous findings...
Angen, Øystein; Heegaard, Peter M. H.; Lavritsen, D.T.
In Denmark porcine pleuropneumonia is most frequently caused by Actinobacillus pleuropneumoniae serotype 2 (60%). Isolation of A. pleuropneumoniae from nasal cavities or tonsils from carrier animals is complicated due to the mixed bacterial flora present. An immunomagnetic separation technique (IMS...... the nasal cavity or tonsils by cultivation or PCR 6 weeks later. By using IMS A. pleuropneumoniae serotype 2 could be reisolated from the tonsils of three pigs. The LMS method represents a valuable tool for isolation of A. pleuropneumoniae from tissue samples....
Simultaneous detection of antibodies against Apx toxins ApxI, ApxII, ApxIII, and ApxIV in pigs with known and unknown Actinobacillus pleuropneumoniae exposure using a multiplexing liquid array platform.
Giménez-Lirola, Luis G; Jiang, Yong-Hou; Sun, Dong; Hoang, Hai; Yoon, Kyoung-Jin; Halbur, Patrick G; Opriessnig, Tanja
Surveillance for the presence of Actinobacillus pleuropneumoniae infection in a population plays a central role in controlling the disease. In this study, a 4-plex fluorescent microbead-based immunoassay (FMIA), developed for the simultaneous detection of IgG antibodies to repeat-in-toxin (RTX) toxins (ApxI, ApxII, ApxIII, and ApxIV) of A. pleuropneumoniae, was evaluated using (i) blood serum samples from pigs experimentally infected with each of the 15 known A. pleuropneumoniae serovars or with Actinobacillus suis, (ii) blood serum samples from pigs vaccinated with a bacterin containing A. pleuropneumoniae serovar 1, 3, 5, or 7, and (iii) blood serum samples from pigs with an unknown A. pleuropneumoniae exposure status. The results were compared to those obtained in a previous study where a dual-plate complement fixation test (CFT) and three commercially available enzyme-linked immunosorbent assays (ELISAs) were conducted on the same sample set. On samples from experimentally infected pigs, the 4-plex Apx FMIA detected specific seroconversion to Apx toxins as early as 7 days postinfection in a total of 29 pigs inoculated with 14 of the 15 A. pleuropneumoniae serovars. Seroconversion to ApxII and ApxIII was detected by FMIA in pigs inoculated with A. suis. The vaccinated pigs showed poor humoral responses against ApxI, ApxII, ApxIII, and ApxIV. In the field samples, the humoral response to ApxIV and the A. pleuropneumoniae seroprevalence increased with age. This novel FMIA (with a sensitivity of 82.7% and a specificity of 100% for the anti-ApxIV antibody) was found to be more sensitive and accurate than current tests (sensitivities, 9.5 to 56%; specificity, 100%) and is potentially an improved tool for the surveillance of disease and for monitoring vaccination compliance.
Hsu, C-K; Zink, A; Wei, K-J; Dzika, E; Plewig, G; Chen, W
Human Demodex mites (Demodex folliculorum and Demodex brevis) are unique in that they are an obligate human ectoparasite that can inhabit the pilosebaceous unit lifelong without causing obvious host immune response in most cases. The mode of symbiosis between humans and human Demodex mites is unclear, while the pathogenicity of human Demodex mites in many inflammatory skin diseases is now better understood. Primary human demodicosis is a skin disease sui generis not associated with local or systemic immunosuppression. Diagnosis is often underestimated and differentiation from folliculitis, papulopustular rosacea and perioral dermatitis is not always straightforward. Dependent on the morphology and degree of inflammation, the clinical manifestations can be classified into spinulate, papulopustular, nodulocystic, crustic and fulminant demodicosis. Therapy success can be achieved only with acaricides/arachidicides. The effective doses, optimal regimen and antimicrobial resistance remain to be determined.
Successful innovative 'leaps' in surgical technique have the potential to contribute exponentially to surgical advancement, and thereby to improved health outcomes for patients. Such innovative leaps often occur relatively spontaneously, without substantial forethought, planning, or preparation. This feature of surgical innovation raises special challenges for ensuring sufficient evaluation and regulatory oversight of new interventions that have not been the subject of controlled investigatory exploration and review. It is this feature in particular that makes early-stage surgical innovation especially resistant to classification as 'research', with all of the attendant methodological and ethical obligations--of planning, regulation, monitoring, reporting, and publication--associated with such a classification. This paper proposes conceptual and ethical grounds for a restricted definition according to which innovation in surgical technique is classified as a form of sui generis surgical 'research', where the explicit goal of adopting such a definition is to bring about needed improvements in knowledge transfer and thereby benefit current and future patients.
Sauer, Elizabeta; Merdanovic, Melisa; Mortimer, Anne Price; Bringmann, Gerhard; Reidl, Joachim
The utilization pathway for the uptake of NAD and nicotinamide riboside was previously characterized for Haemophilus influenzae. We now report on the cellular location, topology, and substrate specificity of PnuC. pnuC of H. influenzae is only distantly related to pnuC of Escherichia coli and Salmonella enterica serovar Typhimurium. When E. coli PnuC was expressed in an H. influenzae pnuC mutant, it was able to take up only nicotinamide riboside and not nicotinamide mononucleotide. Therefore, we postulated that PnuC transporters in general possess specificity for nicotinamide riboside. Earlier studies showed that 3-aminopyridine derivatives (e.g., 3-aminopyridine adenine dinucleotide) are inhibitory for H. influenzae growth. By testing characterized strains with mutations in the NAD utilization pathway, we show that 3-aminopyridine riboside is inhibitory to H. influenzae and is taken up by the NAD-processing and nicotinamide riboside route. 3-Aminopyridine riboside is utilized effectively in a pnuC+ background. In addition, we demonstrate that 3-aminopyridine adenine dinucleotide resynthesis is produced by NadR. 3-Aminopyridine riboside-resistant H. influenzae isolates were characterized, and mutations in nadR could be detected. We also tested other species of the family Pasteurellaceae, Pasteurella multocida and Actinobacillus actinomycetemcomitans, and found that 3-aminopyridine riboside does not act as a growth inhibitor; hence, 3-aminopyridine riboside represents an anti-infective agent with a very narrow host range.
de Ceuster, Laura M E; van Dillen, Jeroen J; Wever, Peter C; Rozemeijer, Wouter; Louwerse, Elisabeth S
In the Netherlands, Streptococcus suis is a rare cause of meningitis. Over the past few years, the number of reported cases worldwide has increased. The bacterium is mainly isolated in pigs, but humans can also become infected. At the Emergency Department, a 60-year-old man presented with headache, confusion, fever and nuchal rigidity. He worked at a meat factory. Laboratory testing showed abnormalities linked to bacterial meningitis. S. suis was cultured from blood and cerebrospinal fluid. The patient was treated with dexamethasone, ceftriaxone and later benzylpenicillin intravenously. He recovered well, but had bilateral perceptive hearing loss as a sequela. Particularly people who are in close contact with pigs have an increased risk of S. suis infection. S. suis meningitis can be very severe and lead to serious complications and even death. Rapid diagnosis and adequate treatment are critical. Permanent hearing loss is the most frequent sequela.
Peet-Schwering, van der C.M.C.; Binnendijk, G.P.; Dirx-Kuijken, N.C.P.M.M.; Raymakers, R.; Lamers, J.
Via een vragenlijst, die ingevuld is door 50 varkenshouders, is inzicht verkregen in risicofactoren ten aanzien van Streptococcus suis bij gespeende biggen en in managementmaatregelen die varkenshouders kunnen nemen om de streptococcenproblematiek op hun bedrijf te verminderen
Wisselink, H.J.; Reek, F.H.; Vecht, U.; Stockhofe-Zurwieden, N.; Smits, M.A.; Smith, H.E.
We developed a PCR assay for the rapid and sensitive detection of virulent Streptococcus suis type 2 and highly virulent S. suis type 1 in tonsillar specimens from pigs. The PCR primers were based on the sequence of the gene encoding the EF-protein of virulent S. suis type 2 strains (MRP EF ) and hi
Cutillas, C; Callejón, R; de Rojas, M; Tewes, B; Ubeda, J M; Ariza, C; Guevara, D C
In this paper, a morphological and biometrical study by optical microscopy and scanning electronic microscopy (SEM) of Trichuris suis isolated from different hosts (Sus scrofa domestica and Sus scrofa scrofa) and Trichuris trichiura isolated from chimpanzee, has been carried out. Our results demonstrate the existence of typical pericloacal papillae in both species. Biometrical parameters of T. suis and T. trichiura overlapped but males and females of T. trichiura tended to be shorter and thinner than those of T. suis. Our results suggest that T. suis and T. trichiura cannot be differentiated using standard procedures as morphological and biometrical determinations. Thus, the ITS1-5.8S-ITS2 region of the ribosomal DNA was sequenced to allow a differentiation between T. suis and T. trichiura on genetic level. The ITS1 and ITS2 sequences derived from T. trichiura eggs isolated from feces of primates (Colobus guereza kikuyensis and Nomascus gabriellae) showed clear differences to the respective sequences of T. suis derived from eggs of different porcine hosts. The 5.8S gene was similar between the two species. Sequences obtained from different populations of the same species showed no significant differences indicating that the ITS1-5.8S-ITS2 sequences reported in this study are representative for T. trichiura and T. suis, respectively. Phylogenetic relationships have been determined attending to the ITS1 and ITS2 sequences from different species of the genus Trichuris. In conclusion, T. trichiura and T. suis are considered to be closely related but genetically different species. Both species can be easily and reliably distinguished by a PCR-RFLP analysis of the ITS1 and ITS2 sequences with different restriction enzymes.
Ji, Wenhui; Huang, Qingqing; Sun, Liang; Wang, Hengan; Yan, Yaxian; Sun, Jianhe
Streptococcus suis serotype 2 (S. suis 2) is a zoonotic pathogen that exhibits high-level resistance and multi-drug resistance to classic antibiotics and causes serious human casualties and heavy economic losses in the swine industry worldwide. Therefore, alternative therapies or novel antibacterial agents need to be developed to combat this pathogen. A novel endolysin derived from the S. suis temperate phage phi7917, termed Ly7917, was identified, which had broad lytic activity against S. suis type 1, 2, 7 and 9. Ly7917 consisted of an N-terminal cysteine, histidine-dependent amidohydrolases/peptidase catalytic domain and C-terminal SH3b cell wall binding domain. The endolysin maintained activity at high pH and its catalytic activity could be improved by addition of 10 μM 1.5 mM Ca(2+). In animal studies, 90% of BALB/c mice challenged with typical virulent strain HA9801 of S. suis 2 were protected by Ly7917 treatment. The bacterial load in the blood of HA9801-challenged mice was efficiently reduced almost 50% by Ly7917 while that of penicillin-G-treated mice kept almost unchanged. Our data suggest that Ly7917 may be an alternative therapeutic agent for infections caused by virulent S. suis strains.
Nan, Wenlong; Tan, Pengfei; Wang, Yong; Xu, Zouliang; Mao, Kairong; Peng, Daxin; Chen, Yiping
Immunisation with attenuated Brucella spp. vaccines prevents brucellosis, but may also interfere with diagnosis. In this study, a duplex PCR was developed to distinguish Brucella suis vaccine strain S2 from field strains of B. suis biovar 1 and other Brucella spp. The PCR detected 60 fg genomic DNA of B. suis S2 or biovar 1 field strains and was able to distinguish B. suis S2 and wild-type strains of B. suis biovar 1 among 76 field isolates representing all the common species and biovars, as well as four vaccine strains, of Brucella.
Hare, K M; Binks, M J; Grimwood, K; Chang, A B; Leach, A J; Smith-Vaughan, H
A PCR for protein D (hpd#3) was used to differentiate nontypeable Haemophilus influenzae (NTHI) from Haemophilus haemolyticus. While 90% of nasopharyngeal specimens and 100% of lower-airway specimens from 84 Indigenous Australian children with bronchiectasis had phenotypic NTHI isolates confirmed as H. influenzae, only 39% of oropharyngeal specimens with phenotypic NTHI had H. influenzae. The nasopharynx is therefore the preferred site for NTHI colonization studies, and NTHI is confirmed as an important lower-airway pathogen.
Nasimi, Elnara [Faculty of Energy Systems and Nuclear Science, University of Ontario Institute of Technology, 2000 Simcoe St. N., Oshawa, L1H 7K4 ON (Canada); Gabbar, Hossam A., E-mail: email@example.com [Faculty of Energy Systems and Nuclear Science, University of Ontario Institute of Technology, 2000 Simcoe St. N., Oshawa, L1H 7K4 ON (Canada)
Highlights: Black-Right-Pointing-Pointer Review of current SUI technologies and challenges. Black-Right-Pointing-Pointer Propose a new type of SUI detectors. Black-Right-Pointing-Pointer Propose a new SUI system architecture and layout. Black-Right-Pointing-Pointer Propose implementation procedure for SUI with reduced risks. - Abstract: Due to the age and operating experience of Nuclear Power Plants, equipment ageing and obsolescence has become one of the main challenges that need to be resolved for all systems, structures and components in order to ensure a safe and reliable production of energy. This paper summarizes the research into a methodology for modernization of Start-Up Instrumentation (SUI), both in-core and Control Room equipment, using a new generation of detectors and cables in order to manage obsolescence. The main objective of this research is to develop a new systematic approach to SUI installation/replacement procedure development and optimization. Although some additional features, such as real-time data monitoring and storage/archiving solutions for SUI systems are also examined to take full advantage of today's digital technology, the objectives of this study do not include detailed parametrical studies of detector or system performance. Instead, a number of technological, operational and maintenance issues associated with Start-Up Instrumentation systems at Nuclear Power Plants (NPPs) will be identified and a structured approach for developing a replacement/installation procedure that can be standardized and used across all of the domestic CANDU (Canadian Deuterium Uranium) stations is proposed.
Hansen, Tina V.A.; Friis, Christian; Nejsum, Peter; Olsen, Annette; Thamsborg, Stig Milan
It is recognized that the clinical efficacy of single dose benzimidazoles (BZs) against the nematode, Trichuris suis of pigs and the closely related Trichuris trichiura in humans is only poor to moderate. Recent in vitro studies have indicated that a low uptake of fenbendazole (FBZ) in T. suis may be responsible for its poor efficacy. The aim of this study was to investigate this hypothesis by measuring the concentrations of FBZ and its metabolites, oxfendazole (OXF) and FBZ sulphone (FBZSO2), in T. suis isolated from FBZ treated pigs and in plasma of the pigs. The highest concentration of FBZ measured in T. suis was 66.6 pmol/mg dry worm tissue which was approximately half of what was measured in a previous in vitro study. The correlation between drug concentrations in plasma and in T. suis worms was highly positive for OXF (r = 0.93, P = 0.0007) and FBZSO2 (r = 0.85, P = 0.007), but no correlation was found for FBZ. This study shows that the low uptake of FBZ observed for T. suis in vitro, also takes place in vivo. The high and significant correlations between OXF and FBZSO2 concentrations in plasma of the pigs and T. suis (and the lack of this correlation for FBZ) suggests that the metabolites reach the worms via the blood–enterocyte interface while FBZ primarily reaches the worms via the intestinal lumen of the host. PMID:25057460
DNA recombination in exponential phase and competent Haemophilus influenzae was measured by an electron microscopic assay that relies on the conversion of plasmid RSF0885 monomers into multimeric forms. Dimer circles were present at a frequency of 2% in plasmid preparations from competent Rd (wild-type) cells; multimers were present at a frequency of 0.2% in preparations from exponential phase cells. Thus, plasmid recombination was stimulated in competent cells. Multimer formation occurred efficiently in cells of the transformation defective mutant rec2, implying that the rec2 gene product is not required for plasmid recombination. However, the absence of multimer plasmids in preparations from competent cells of the transformation defective mutant rec1 suggests that the rec1 gene product is required. Digestion of purified plasmids with restriction endonuclease PvuII, which makes a single cut in the monomer, revealed the presence of recombination intermediates composed of two linear plasmids joined to form two pairs of arms resembling the Greek letter chi. Length measurements of these arms taken from a population of recombination intermediates gave evidence that the plasmids were joined at sites of homology. The distributions of individual DNA strands, at the intersections of the four arms, could be resolved in some recombination intermediates and were of two types. The first type of junction appeared as a single-stranded arm appended to each corner. The second type of junction consisted of a single strand of DNA linking the two linear plasmids at a site of homology. The single-stranded linker was frequently situated at the edge of a short gap on one of the plasmids in the pair. The fine structures of the recombinational joints have been interpreted in terms of previously proposed models of recombination.
Full Text Available Abstract Background In pigs little is known about the role of innate immune defence in bacterial infections of the respiratory tract, despite their major role in pig production. In the present study we characterized and compared in vitro and in vivo activation of immune markers of different pig breeds 7 days before, and 4 and 21 days after an experimental aerosol infection with Actinobacillus (A. pleuropneumoniae. Results In vitro stimulation of bronchoalveolar lavage fluid (BALF and blood leukocytes with A. pleuropneumoniae, Streptococcus suis, PMA and LPS led to production of different amounts of H2O2, NO and TNF-α, depending on the stimulus, individual, breed and time of infection. Generally, significant responses to in vitro stimulation were observed only in blood leukocytes, whereas the alveolar macrophages showed a high basal activation. In addition, the production of haptoglobin and cytokines (TNF-α, IFN-γ and IL-10 in vivo was measured in plasma and BALF. Plasma haptoglobin levels mirrored the clinical manifestations at 4 days post-infection. In plasma and BALF TNF-α could not be detected, whereas variable levels of IFN-γ were found at pre- and post-infection times. IL-10 was found in some plasma but in none of the BALF samples. The different expression levels in individuals within the breeds correlated for some markers with the severity of clinical manifestations, e.g. H2O2, plasma haptoglobin and BALF IFN-γ for German Landrace pigs. Conclusion Our findings revealed differences in the activation of the immune markers with respect to infection time, individuals and breeds. Moreover, results showed different correlation grades between the immune markers produced in vitro or in vivo and the clinical manifestations. Further analyses will have to show whether these markers may serve as correlates of protection against porcine respiratory infections.
Vigre, Håkan; Sørensen, Vibeke; Ersbøll, Annette Kjær
The main objective of this study was to estimate the decay of acquired colostral antibodies to Actinobacillus pleuropneumoniae serotype 2 in pigs. Data were obtained from pigs in an isolated cohort of 47 pigs born to five sows seropositive to A. pleuropneumoniae serotype 2. The pigs were examined...... serologically at 18 different times from birth until an age of about 22 weeks, using an A. pleuropneumoniae serotype 2-specific blocking enzyme-linked immunosorbent assay. Antibody concentration was expressed as an OD% derived from the optical density of the sample and the median from eight wells without serum...... on the initial level of acquired colostral antibodies to A. pleuropneumoniae serotype 2....
Dr. Elizabeth Briere discusses Nontypeable Haemophilus influenzae which causes a variety of infections in children and adults. Created: 11/12/2015 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID). Date Released: 11/17/2015.
Herbert, Mark; Sauer, Elizabeta; Smethurst, Graeme; Kraiss, Anita; Hilpert, Anna-Karina; Reidl, Joachim
The gene for the nicotinamide riboside (NR) transporter (pnuC) was identified in Haemophilus influenzae. A pnuC mutant had only residual NR uptake and could survive in vitro with high concentrations of NR, but could not survive in vivo. PnuC may represent a target for the development of inhibitors for preventing H. influenzae disease.
Full Text Available Blood platelets play important roles during pathological thrombocytopenia in streptococcal toxic shock syndrome (STSS. Streptococcus suis (S. suis an emerging human pathogen, can cause STSS similarly to S. pyogenes. However, S. suis interactions with platelets are poorly understood. Here, we found that suilysin (SLY, different from other bacterial cholesterol-dependent cytolysins (CDCs, was the sole stimulus that induced platelet aggregation. Furthermore, the inside-out activation of GPIIb/IIIa of platelets mediated SLY-induced platelet aggregation. This process was triggered by Ca2+ influx that depend on the pore forming on platelets by SLY. Additionally, although SLY induced α-granule release occurred via the MLCK-dependent pathway, PLC-β-IP3/DAG-MLCK and Rho-ROCK-MLCK signaling were not involved in SLY-induced platelet aggregation. Interestingly, the pore dependent Ca2+ influx was also found to participate in the induction of platelet aggregation with pneumolysin (PLY and streptolysin O (SLO, two other CDCs. It is possible that the CDC-mediated platelet aggregation we observed in S. suis is a similar response mechanism to that used by a wide range of bacteria. These findings might lead to the discovery of potential therapeutic targets for S. suis-associated STSS.
Zhang, Shengwei; Wang, Junping; Chen, Shaolong; Yin, Jiye; Pan, Zhiyuan; Liu, Keke; Li, Lin; Zheng, Yuling; Yuan, Yuan; Jiang, Yongqiang
Blood platelets play important roles during pathological thrombocytopenia in streptococcal toxic shock syndrome (STSS). Streptococcus suis (S. suis) an emerging human pathogen, can cause STSS similarly to S. pyogenes. However, S. suis interactions with platelets are poorly understood. Here, we found that suilysin (SLY), different from other bacterial cholesterol-dependent cytolysins (CDCs), was the sole stimulus that induced platelet aggregation. Furthermore, the inside-out activation of GPIIb/IIIa of platelets mediated SLY-induced platelet aggregation. This process was triggered by Ca2+ influx that depend on the pore forming on platelets by SLY. Additionally, although SLY induced α-granule release occurred via the MLCK-dependent pathway, PLC-β-IP3/DAG-MLCK and Rho-ROCK-MLCK signaling were not involved in SLY-induced platelet aggregation. Interestingly, the pore dependent Ca2+ influx was also found to participate in the induction of platelet aggregation with pneumolysin (PLY) and streptolysin O (SLO), two other CDCs. It is possible that the CDC-mediated platelet aggregation we observed in S. suis is a similar response mechanism to that used by a wide range of bacteria. These findings might lead to the discovery of potential therapeutic targets for S. suis-associated STSS. PMID:27800304
Ferrando, Maria Laura; de Greeff, Astrid; van Rooijen, Willemien J. M.;
of SS2 infection. Methods. We developed a noninvasive in vivo model to study oral SS2 infection in piglets. We compared in vitro interaction of S. suis with human and porcine intestinal epithelial cells (IEC). Results. Two out of 15 piglets showed clinical symptoms compatible with S. suis infection 24...... be considered a food-borne pathogen. S. suis interaction with human and pig IEC correlates with S. suis serotype and genotype, which can explain the zoonotic potential of SS2....
Yuan, Fangyan; Liao, Yonghong; You, Wujin; Liu, Zewen; Tan, Yongqiang; Zheng, Chengkun; BinWang; Zhou, Danna; Tian, Yongxiang; Bei, Weicheng
The znuA gene is known to be important for growth and survival in Escherichia coli, Haemophilus spp., Neisseria gonorrhoeae, and Pasteurella multocida under low Zn(2+) conditions. This gene is also present in Actinobacillus pleuropneumoniae serotype 1; therefore, the aim of this study was to investigate the existence of a similar role for the znuA gene in the growth and virulence of this organism. A precisely defined ΔznuA deletion mutant of A. pleuropneumoniae was constructed based on the sequence of the wild-type SLW01 using transconjugation and counterselection. This mutation was found to be lethal in low-Zn(2+) medium. Furthermore, the ΔznuA mutant strain exhibited attenuated virulence (≥22-fold) as well as reduced mortality and morbidity in a murine (Balb/C) model of infection. The majority of the bacteria were cleared from the lungs within 2 weeks. The ΔznuA mutant strain caused no adverse effects in pigs at doses of up to 1.0×10(9) CFU/mL. The ΔznuA mutant strain induced a significant immune response and conferred 80% and 100% protection on immunised pigs against challenge with A. pleuropneumoniae strains belonging to homologous or heterologous serovars, respectively, compared to the blank controls. The data obtained in this study indicate the potential of the mutant ΔznuA strain for development as a live vaccine capable of inducing reliable cross-serovar protection following intratracheal immunisation. Copyright © 2014 Elsevier B.V. All rights reserved.
Joosten, Myrthe; Flahou, Bram; Meyns, Tom; Smet, Annemieke; Arts, Joris; De Cooman, Lien; Pasmans, Frank; Ducatelle, Richard; Haesebrouck, Freddy
This study describes a non-Helicobacter (H.) pylori Helicobacter (NHPH) infection in a pig veterinarian. The patient suffered from reflux esophagitis and general dyspeptic symptoms and was referred to the hospital for upper gastrointestinal endoscopy. Histologic examination of corpus and antrum biopsies revealed a chronic gastritis. Large spiral-shaped non-H. pylori helicobacters could be visualized and were identified as H. suis by PCR. The patient was treated with a triple therapy, consisting of amoxicillin, clarithromycin, and pantoprazole for 10 days. Successful eradication was confirmed after a follow-up gastrointestinal endoscopy and PCR 10 weeks after treatment. A mild chronic gastritis was, however, still observed at this point in time. This case report associates porcine H. suis strains with gastric disease in humans, thus emphasizing the zoonotic importance of H. suis bacteria from pigs. © 2013 John Wiley & Sons Ltd.
Full Text Available Streptococcus suis is a facultative anaerobic, Gram-positive coccus that can cause severe disease to both pigs and humans. Its zoonotic potential was first recognized in 1968 when the first human case of meningitis was reported in Denmark. Since then, over 1600 human cases have been reported worldwide, the vast majority of which originated in Southeast Asia, and, thus, S. suis has been fairly characterized as an emerging pathogen. Infection in humans presents most commonly as bacteremia and/or meningitis while less common clinical manifestations such as endocarditis and septic arthritis can occur. S. suis infection is extremely uncommon in Greece and this is the third human case to be reported. Correct identification is of importance for optimization of antimicrobial treatment and epidemiological monitoring.
Full Text Available En la literatura científica existen varias líneas de evidencia que relacionan directamente al Actinobacillus actinomycetemcomitans con lesiones de Periodontitis juvenil localizada y aunque existe evidencia de transmisión familiar de este patógeno periodontal, no existe constancia de que la enfermedad periodontal sea contagiosa. Las bacterias responsables de la enfermedad periodontal parecen ser transmisibles, pero sólo después de un periodo largo de exposición. La vía de transmisión tampoco está clara. Por el momento no es posible sacar ninguna conclusión al respecto.In scientific literature several lines of evidence exist and link Actinobacillus actinomycetemcomitans with localized juvenile periodontitis lesions directly. Although evidence of familial transmission exist, it doesn't prove periodontal disease is contagious. Bacteria responsible for periodontal disease seem to be transmissible, but only after a long exposure period. No clear transmission paths were observed in the population yet. Up to now drawing conclusions about it is not possible.
Nielsen, R.; Andresen, Lars Ole; Plambeck, Tamara
Nine Danish Actinobacillus pleuropneumoniae biotype 1 isolates were shown by latex agglutination and indirect haemagglutination to possess capsular polysaccharide epitopes identical to those of serotype 2 strain 1536 (reference strain of serotype 2) and strain 4226 (Danish serotype 2 strain...
Schou, Kirstine Klitgaard; Angen, Øystein; Boye, Mette
Until now, 15 different serotypes of Actinobacillus pleuropneumoniae (Ap) have been described based upon differences in the capsular polysaccharides of the bacterium. The virulence of different serotypes of Ap has been experimentally determined and the differences in mortality and morbidity...
Morter Flores, José Luis
La presente tesis investiga la incidencia de la Pleuroneumonía porcina, ocasionada por Actinobacillus pleuropneumoniae, en ciertos roedores como ratas y ratones, estimando su índice de infección en un 33,6 %.
Garcia P., Omar; Calle E., Sonia; Falcon P., Nestor; Torres A., Marlon; Pinto J., Chris
En el presente estudio se, observo la persistencia de la inmunidad pasiva en porcinos procedentes de madres seropositivas a Actinobacillus pleuropneumoniae desde el destete hasta el final del periodo...
Aalbæk, Bent; Østergaard, Stine; Buhl, Rikke
Microbiological and pathological data from a case of equine valvular endocarditis are reported. Limited information is available on the pathogenic potential of equine Actinobacillus species as several strains originate from apparently healthy horses. After the establishment of two subspecies within...
Anusha van Samkar
Full Text Available Streptococcus suis is the most common cause of meningitis in pork consuming and pig rearing countries in South-East Asia. We performed a systematic review of studies on S. suis meningitis to define the clinical characteristics, predisposing factors and outcome.Studies published between January 1, 1980 and August 1, 2015 were identified from main literature databases and reference lists. Studies were included if they were written in West-European languages and described at least 5 adult patients with S. suis meningitis in whom at least one clinical characteristic was described.We identified 913 patients with S. suis meningitis included in 24 studies between 1980 and 2015. The mean age was 49 years and 581 of 711 patients were male (82%. Exposure to pigs or pork was present in 395 of 648 patients (61% while other predisposing factors were less common. 514 of 528 patients presented with fever (97%, 429 of 451 with headache (95%, 462 of 496 with neck stiffness (93% and 78 of 384 patients (20% had a skin injury in the presence of pig/pork contact. The case fatality rate was 2.9% and hearing loss was a common sequel occurring in 259 of 489 patients (53%. Treatment included dexamethasone in 157 of 300 (52% of patients and was associated with reduced hearing loss in S. suis meningitis patients included in a randomized controlled trial.S. suis meningitis has a clear association with pig and pork contact. Mortality is low, but hearing loss occurs frequently. Dexamethasone was shown to reduce hearing loss.
Full Text Available Very few Streptococcus suis infections in humans have been reported in Canada, although the condition is frequent in pigs. Meningitis, often accompanied by severe hearing loss, is the most common clinical manifestation. The disease is an occupational illness affecting persons in contact with pigs and may be underdiagnosed because of misidentification of the responsible bacterium. Since Quebec is the leading province for swine production in Canada, physicians and microbiologists should be aware of this infection, especially when a streptococcal meningitis is diagnosed in swine workers. The first case of S suis type 2 meningitis reported in Quebec is described.
Stuart, B P; Gosser, H S; Allen, C B; Bedell, D M
Coccidiosis is a disease of the young piglet due to infection with Isospora suis and is characterized by diarrhea which is nonresponsive to antibacterial therapy. There is variable morbidity and mortality. Piglets develop a more severe clinical illness and enteritis when infected with I. suis at one to three days of age than when infected at two weeks of age. Microscopic lesions range from villous atrophy and mild erosion to severe fibrinonecrotic enteritis. Images Fig. 1. Fig. 2. Fig. 3. Fig. 4. Fig. 5. PMID:6889908
Padronização de três ELISAs polivalentes com lipopolissacarídeos de cadeia longa dos sorotipos 1 e 5, 2, 3 e 7 ou 10 e 12 de Actinobacillus pleuropneumoniae Standardization of three polyvalent ELISA based on long chain lipopolysaccharides of serotypes 1 and 5, 2, 3 and 7, or 10 and 12 of Actinobacillus pleuropneumoniae
Full Text Available Três ELISAs polivalentes baseados em lipopolissacarídeos de cadeia longa (LPS-CL foram estabelecidos para detectar anticorpos para todos os sorotipos prevalentes de Actinobacillus pleuropneumoniae. Foram testadas amostras provenientes do banco de soros de suínos experimentalmente inoculados com todos os sorotipos de A. pleuropneumoniae. Os ELISAs foram sensíveis à detecção de anticorpos contra todos os LPS-CL. Foram observadas reações cruzadas no ELISA polivalente produzido com os sorotipos 1 e 5, com anti-soros específicos para os sorotipos 9 e 11, pois os sorotipos 1, 9 e 11 apresentaram antígenos somáticos comuns. No polivalente com os sorotipos 2, 3 e 7, observaram-se reações com anti-soros dos sorotipos 4, 6 e 8, devido à presença de antígenos somáticos entre os sorotipos 3, 6 e 8 e entre os sorotipos 4 e 7. Amostras de soros de animais infectados com Mycoplasma hyopneumoniae, Mycoplasma flocculare e Haemophilus parasuis, agentes que acometem o sistema respiratório dos suínos, não apresentaram reações cruzadas com os antígenos baseados em LPS-CL.Three polyvalent ELISA based on long chain lipopolysaccharides (LC-LPS were established to detect all prevalent serotypes of Actinobacillus pleuropneumoniae. Samples from a serum bank of experimentally inoculated animals with all serotypes of A. pleuropneumoniae were tested. Antibodies specific to LC-LPS of each serotype were detected. Cross-reactions were observed in the polyvalent ELISA produced with serotypes 1 and 5, with specific antisera to serotypes 9 and 11 due to common somatic antigens presence in serotypes 1, 9, and 11. In the polyvalent with serotypes 2, 3 and 7 reactions were observed with antisera of serotypes 4, 6, and 8, due to the presence of somatic antigens in serotypes 3, 6, and 8 and serotypes 4 and 7. Experimentally infected animals with respiratory agents of swine Mycoplasma hyopneumoniae, Mycoplasma flocculare, and Haemophilus parasuis did not present
Albritton, W L; Maclean, I W; Slaney, L A; Ronald, A. R.; Deneer, H G
Clinical isolates of Haemophilus ducreyi were shown to be resistant to tetracycline. Resistance was associated in some strains with a 30-megadalton plasmid capable of transferring resistance in conjugative matings with other strains of H. ducreyi and other species of Haemophilus. Restriction endonuclease digestion patterns suggest a relationship between H. ducreyi plasmids and other tetracycline resistance plasmids in Haemophilus. The presence of plasmid-mediated resistance to the tetracyclin...
Full Text Available S. suis (Streptococcus suis caused serious disease symptoms in humans and pigs. S. suis is able to form thick biofilms and this increases the difficulty of treatment. After growth with 1/2 MIC of azithromycin, 1/4 MIC of azithromycin, or 1/8 MIC of azithromycin, biofilm formation of S. suis dose-dependently decreased in the present study. Furthermore, scanning electron microscopy analysis revealed the obvious effect of azithromycin against biofilm formation of S. suis. Especially, at two different conditions (1/2 MIC of azithromycin nontreated cells and treated cells, we carried out comparative proteomic analyses of cells by using iTRAQ technology. Finally, the results revealed the existence of 19 proteins of varying amounts. Interestingly, several cell surface proteins (such as ABC superfamily ATP binding cassette transporter (G7SD52, CpsR (K0FG35, Cps1/2H (G8DTL7, CPS16F (E9NQ13, Putative uncharacterized protein (G7SER0, NADP-dependent glyceraldehyde-3-phosphate dehydrogenase (G5L259, Putative uncharacterized protein (G7S2D6, Amino acid permease (B0M0G6 and NsuB (G5L351 were found to be implicated in biofilm formation. More importantly, we also found that azithromycin affected expression of the genes cps1/2H, cpsR and cps16F. Especially, after growth with 1/2 MIC of azithromycin and 1/4 MIC of azithromycin, the capsular polysaccharide (CP content of S. suis was significantly higher.
Yang, Yan-Bei; Chen, Jian-Qing; Zhao, Yu-Lin; Bai, Jing-Wen; Ding, Wen-Ya; Zhou, Yong-Hui; Chen, Xue-Ying; Liu, Di; Li, Yan-Hua
Streptococcus suis (S. suis) caused serious disease symptoms in humans and pigs. S. suis is able to form thick biofilms and this increases the difficulty of treatment. After growth with 1/2 minimal inhibitory concentration (MIC) of azithromycin, 1/4 MIC of azithromycin, or 1/8 MIC of azithromycin, biofilm formation of S. suis dose-dependently decreased in the present study. Furthermore, scanning electron microscopy analysis revealed the obvious effect of azithromycin against biofilm formation of S. suis. Especially, at two different conditions (1/2 MIC of azithromycin non-treated cells and treated cells), we carried out comparative proteomic analyses of cells by using iTRAQ technology. Finally, the results revealed the existence of 19 proteins of varying amounts. Interestingly, several cell surface proteins (such as ATP-binding cassette superfamily ATP-binding cassette transporter (G7SD52), CpsR (K0FG35), Cps1/2H (G8DTL7), CPS16F (E9NQ13), putative uncharacterized protein (G7SER0), NADP-dependent glyceraldehyde-3-phosphate dehydrogenase (G5L259), putative uncharacterized protein (G7S2D6), amino acid permease (B0M0G6), and NsuB (G5L351)) were found to be implicated in biofilm formation. More importantly, we also found that azithromycin affected expression of the genes cps1/2H, cpsR and cps16F. Especially, after growth with 1/2 MIC of azithromycin and 1/4 MIC of azithromycin, the capsular polysaccharide content of S. suis was significantly higher. PMID:27812354
Heiman F L Wertheim
Full Text Available BACKGROUND: Streptococcus suis can cause severe systemic infection in adults exposed to infected pigs or after consumption of undercooked pig products. S. suis is often misdiagnosed, due to lack of awareness and improper testing. Here we report the first fifty cases diagnosed with S. suis infection in northern Viet Nam. METHODOLOGY/PRINCIPAL FINDINGS: In 2007, diagnostics for S. suis were set up at a national hospital in Hanoi. That year there were 43 S. suis positive cerebrospinal fluid samples, of which S. suis could be cultured in 32 cases and 11 cases were only positive by PCR. Seven patients were blood culture positive for S. suis but CSF culture and PCR negative; making a total of 50 patients with laboratory confirmed S. suis infection in 2007. The number of S. suis cases peaked during the warmer months. CONCLUSIONS/SIGNIFICANCE: S. suis was commonly diagnosed as a cause of bacterial meningitis in adults in northern Viet Nam. In countries where there is intense and widespread exposure of humans to pigs, S. suis can be an important human pathogen.
Lagergård, T; Purvén, M
Neutralizing antibodies against cytotoxin produced by Haemophilus ducreyi bacteria were studied in rabbits by an assay employing HEp-2 cells and diluted crude cytotoxin preparations from the organism. Antisera to 12 different H. ducreyi strains were prepared by immunization of rabbits with bacterial sonicates combined with Freund's adjuvant. The antibody response during infection with H. ducreyi was studied in two groups of rabbits which were infected with five live strains by either single o...
de Jonge, Marien I.
The incidence of severe Haemophilus influenza infections, such as sepsis and meningitis, has declined substantially since the introduction of the H. influenzae serotype b vaccine. However, the H. influenzae type b vaccine fails to protect against nontypeable H. influenzae strains, which have become increasingly frequent causes of invasive disease, especially among children and the elderly. We summarize recent literature supporting the emergence of invasive nontypeable H. influenzae and describe mechanisms that may explain its increasing prevalence over the past 2 decades. PMID:26407156
Swildens, B.; Stockhofe-Zurwieden, N.; Meulen, van der J.; Wisselink, H.J.; Nielen, M.; Niewold, T.A.
Sepsis with subsequent multisystem organ failure after translocation of bacteria from the gut is a serious risk associated with stress situations. We showed that intestinal bacterial translocation could be one of the pathways for pathogenic Streptococcus suis infections in the pig. In 24 piglets wei
Tarradas, C; Luque, I; de Andrés, D; Abdel-Aziz Shahein, Y E; Pons, P; González, F; Borge, C; Perea, A
Two cases of meningitis due to Streptococcus suis in humans are reported here. A butcher and an abattoir worker were referred to a health centre in Castellón (Spain) with fever and symptoms of meningitis. After adequate treatment, a slight hipoacusia persisted as sequelae in both cases. Colonies of S. suis group R, serotype 2 and phenotype MRP+EF+ were isolated from cerebroespinal fluid. Epidemiological studies showed that both workers had in common the handling of pork meat of slaughtered healthy pigs from three closed farms. A study of the tonsils from apparently healthy, slaughtered pigs was carried out. A total of 234 tonsillar samples were obtained and 81 strains of S. suis were isolated from them. Serotype 2 appeared to be the most frequent (50.6%), and the analysis for phenotype showed a high percentage of tonsillar strains with the phenotype MRP+EF+ (35.9%). The humans and 28 tonsillar swine strains showed a similar profile (S. suis group R, serotype 2 and phenotype MRP+EF+). A total of 26 of the swine isolates were analysed by ribotyping using EcoRI. The human strains showed the same six-band hybridization pattern that shared five bands with the pattern most frequently shown by most of the tonsillar N. suis group R, serotype 2 and phenotype MRP+EF+ strains, differing only in the lightest, faintest band which was slightly less anodical in human (> or = 1.8 kb) than in swine (approximately 1.8 kb). From these results, both groups of strains, humans and porcine, showed differences; how can these differences in the pattern of ribotyping be explained if they should have the same origin? Is it possible that they have undergone an adaptation to the new host or perhaps the modification is due to other unknown causes? Further studies in this area are required in order to answer these questions.
Angen, Øystein; Jensen, J.; Lavritsen, D. T.
Sequence detection by the 5' nuclease TaqMan assay uses online detection of internal fluorogenic probes in closed PCR tubes. Primers and probe were chosen from a part of the omlA gene common to all serotypes of Actinobacillus pleuropneumoniae, which gave an amplicon of 92 bp, The test was evaluated...... with 73 lung isolates and 120 tonsil isolates of A. pleuropneumoniae as well as with a collection of reference strains. By using a C-t value (cycle number in which the fluorescence exceeds the threshold defined by the software) of 30 as the cutoff limit, the 5' nuclease assay represents a test with 100......, nonspecific reactions appeared when testing dilutions of DNA templates or pure cultures of A. pleuropneumoniae, as well as when testing tonsil scrapings from specific-pathogen-free herds. The diagnostic sensitivity, as evaluated with 586 tonsil scrapings from animals infected with A. pleuropneumoniae...
Kang, Shuai; Li, Zhengwen; Yin, Zhongqiong; Jia, Renyong; Song, Xu; Li, Li; Chen, Zhenzhen; Peng, Lianci; Qu, Jing; Hu, Zhiqiang; Lai, Xin; Wang, Guangxi; Liang, Xiaoxia; He, Changliang; Yin, Lizi
This study demonstrated berberine to be a potential natural compound against Actinobacillus pleuropneumoniae. Liquid doubling dilution, transmission electron microscopy (TEM), SDS-PAGE and 4',6-diamidino-2-phenylindole (DAPI) staining were employed to elucidate the antibacterial activity and mechanism of berberine. The minimal inhibitory concentration of berberine was 0.3125 mg/mL, and time-kill curves showed concentration and time dependence. The TEM micrographs displayed damaged cell wall, concentrated cytoplasm, cytoplasmic content leakage and cell death. SDS-PAGE and DAPI assays revealed that berberine can restrain DNA and protein syntheses. Berberine inhibited the synthesis of proteins associated with the growth and cleavage of bacteria and then blocked the division and development of bacteria. The compound ultimately induced cytoplasm pyknosis and bacterial death.
Lima, Francisca Lúcia; de Carvalho, Maria Auxiliadora Roque; Apolônio, Ana Carolina Morais; Bemquerer, Marcelo Porto; Santoro, Marcelo Matos; Oliveira, Jamil Silvano; Alviano, Celuta Sales; Farias, Luiz de Macêdo
Aggregatibacter (Actinobacillus) actinomycetemcomitans P(7-20) strain isolated from a periodontally diseased patient has produced a bacteriocin (named as actinomycetemcomitin) that is active against Peptostreptococcus anaerobius ATCC 27337. Actinomycetemcomitin was produced during exponential and stationary growth phases, and its amount decreased until it disappeared during the decline growth phase. It was purified by ammonium sulphate precipitation (30-60% saturation), and further by FPLC (mono-Q ionic exchange and Phenyl Superose hydrophobic interaction) and HPLC (C-18 reversed-phase). This bacteriocin loses its activity after incubation at a pH below 7.0 or above 8.0, following heating for 30 min at 45 degrees C, and after treatment with proteolytic enzymes such as trypsin, alpha-chymotrypsin, and papain. Actinomycetemcomitin has a molecular mass of 20.3 KDa and it represents a new bacteriocin from A. actinomycetemcomitans.
Thønnings, Sara; Andersen, Christian Østergaard
Optimal antibiotic treatment strategies of Haemophilus infections are still needed. Therefore, 30-day case fatality rate (CFR) of Haemophilus bacteremia and efficacy of various antibiotic treatment regimes were studied.......Optimal antibiotic treatment strategies of Haemophilus infections are still needed. Therefore, 30-day case fatality rate (CFR) of Haemophilus bacteremia and efficacy of various antibiotic treatment regimes were studied....
Full Text Available Se describe un caso de meningitis por Streptococcus suis en un paciente inmunocompetente. Presentaba astenia, debilidad generalizada, fiebre (39 °C, vómitos, deterioro del sensorio y desorientación témporo-espacial. Los cultivos de sangre (2/2 y de líquido cefalorraquídeo fueron positivos. La identificación preliminar se realizó utilizando las pruebas bioquímicas convencionales y fue completada en el Servicio Bacteriología Especial del INEI-ANLIS "Dr. Carlos G. Malbrán". Se comenzó el tratamiento con ampicilina y ceftriaxona. El microorganismo aislado demostró sensibilidad a ampicilina, cefotaxima y vancomicina. El paciente evolucionó favorablemente, pero se comprobó leve hipoacusia. Reingresó a los 4 meses con marcha atáxica, anacusia en oído izquierdo e hipoacusia en oído derecho. Continúa con seguimiento neurológico y audiométrico. Retrospectivamente se constató el contacto del paciente con cerdos. Se destaca la importancia de la anamnesis para alertar la sospecha de este agente etiológico en meningitis y bacteriemias.A case of Streptococcus suis meningitis is described in an immunocompetent patient presenting asthenia, general weakness, fever, vomiting, sensory deterioration and temporospatial disorder. The cerebrospinal fluid and two blood cultures (2/2 bottles were positive. The isolate was preliminary identified by conventional biochemical tests, and the identification was completed at the Special Bacteriology Service of INEI-ANLIS "Dr. Carlos G. Malbrán". Ampicillin and ceftriaxone treatment was initiated. The isolate was susceptible to ampicillin, cefotaxime and vancomycin. The patient experienced a good outcome but suffered hearing loss. However, after four months he returned with walking ataxia, deafness in his left ear, and hearing loss in the right ear. The patient’s retrospective exposure to pigs had been verified. It is important to evaluate predisposing and epidemiologic factors in order to alert about
Gilmer, Daniel B.; Schmitz, Jonathan E.; Thandar, Mya; Euler, Chad W.; Fischetti, Vincent A.
Streptococcus suis infects pigs worldwide and may be zoonotically transmitted to humans with a mortality rate of up to 20%. S. suis has been shown to develop in vitro resistance to the two leading drugs of choice, penicillin and gentamicin. Because of this, we have pursued an alternative therapy to treat these pathogens using bacteriophage lysins. The bacteriophage lysin PlySs2 is derived from an S. suis phage and displays potent lytic activity against most strains of that species including serotypes 2 and 9. At 64 μg/ml, PlySs2 reduced multiple serotypes of S. suis by 5 to 6-logs within 1 hour in vitro and exhibited a minimum inhibitory concentration (MIC) of 32 μg/ml for a S. suis serotype 2 strain and 64 μg/ml for a serotype 9 strain. Using a single 0.1-mg dose, the colonizing S. suis serotype 9 strain was reduced from the murine intranasal mucosa by >4 logs; a 0.1-mg dose of gentamicin reduced S. suis by 5-logs. While resistance to gentamicin was induced after systematically increasing levels of gentamicin in an S. suis culture, the same protocol resulted in no observable resistance to PlySs2. Thus, PlySs2 has both broad and high killing activity against multiple serotypes and strains of S. suis, making it a possible tool in the control and prevention of S. suis infections in pigs and humans. PMID:28046082
Full Text Available Streptococcus suis is a major porcine and zoonotic pathogen responsible for significant economic losses in the pig industry and an increasing number of human cases. Multiple isolates of S. suis show marked genomic diversity. Here we report the analysis of whole genome sequences of nine pig isolates that caused disease typical of S. suis and had phenotypic characteristics of S. suis, but their genomes were divergent from those of many other S. suis isolates. Comparison of protein sequences predicted from divergent genomes with those from normal S. suis reduced the size of core genome from 793 to only 397 genes. Divergence was clear if phylogenetic analysis was performed on reduced core genes and MLST alleles. Phylogenies based on certain other genes (16S rRNA, sodA, recN and cpn60 did not show divergence for all isolates, suggesting recombination between some divergent isolates with normal S. suis for these genes. Indeed, there is evidence of recent recombination between the divergent and normal S. suis genomes for 249 of 397 core genes. In addition, phylogenetic analysis based on the 16S rRNA gene and 132 genes that were conserved between the divergent isolates and representatives of the broader Streptococcus genus showed that divergent isolates were more closely related to S. suis. Six out of nine divergent isolates possessed a S. suis-like capsule region with variation in capsular gene sequences but the remaining three did not have a discrete capsule locus. The majority (40/70, of virulence-associated genes in normal S. suis were present in the divergent genomes. Overall, the divergent isolates extend the current diversity of S. suis species but the phenotypic similarities and the large amount of gene exchange with normal S. suis gives insufficient evidence to assign these isolates to a new species or subspecies. Further sampling and whole genome analysis of more isolates is warranted to understand the diversity of the species.
Latham, Roger; Zhang, Bowen; Tristram, Stephen
SYBR Green real time PCR assays for protein D (hpd), fuculose kinase (fucK) and [Cu, Zn]-superoxide dismutase (sodC) were designed for use in an algorithm for the identification of Haemophilus influenzae and H. haemolyticus. When tested on 127 H. influenzae and 60 H. haemolyticus all isolates were identified correctly.
Pickering, Janessa; Binks, Michael J; Beissbarth, Jemima; Hare, Kim M; Kirkham, Lea-Ann S; Smith-Vaughan, Heidi
We have developed a PCR-high-resolution melt (PCR-HRM) assay to discriminate nontypeable Haemophilus influenzae (NTHi) colonies from Haemophilus haemolyticus. This method is rapid and robust, with 96% sensitivity and 92% specificity compared to the hpd#3 assay. PCR-HRM is ideal for high-throughput screening for NTHi surveillance and clinical trials.
Yang, Jianhua; Li, Wei; Wang, Dezheng; Wu, Hui; Li, Zhimin; Ye, Qin
Glutathione (GSH), an important bioactive substance, is widely applied in pharmaceutical and food industries. In this work, two bifunctional L-glutathione synthetases (GshF) from Actinobacillus pleuropneumoniae (GshFAp) and Actinobacillus succinogenes (GshFAs) were successfully expressed in Escherichia coli BL-21(DE3). Similar to the GshF from Streptococcus thermophilus (GshFSt), GshFAp and GshFAs can be applied for high titer GSH production because they are less sensitive to end-product inhibition (Ki values 33 and 43 mM, respectively). The active catalytic forms of GshFAs and GshFAp are dimers, consistent with those of GshFPm (GshF from Pasteurella multocida) and GshFSa (GshF from Streptococcus agalactiae), but are different from GshFSt (GshF from S. thermophilus) which is an active monomer. The analysis of the protein sequences and three dimensional structures of GshFs suggested that the binding sites of GshFs for substrates, L-cysteine, L-glutamate, γ-glutamylcysteine, adenosine-triphosphate, and glycine are highly conserved with only very few differences. With sufficient supply of the precursors, the recombinant strains BL-21(DE3)/pET28a-gshFas and BL-21(DE3)/pET28a-gshFap were able to produce 36.6 and 34.1 mM GSH, with the molar yield of 0.92 and 0.85 mol/mol, respectively, based on the added L-cysteine. The results showed that GshFAp and GshFAs are potentially good candidates for industrial GSH production.
Fernanda Akemi Nakanishi
Full Text Available Actinobacillus actinomycetemcomitans produces a protease to human immunoglobulin G that is an important evasion mechanism. In this study, the proteolytic activity of A. actinomycetemcomitans strain ATCC 43718 on human immunoglobulin G associated with culture supernatant concentrations, the growth period and the period of incubation with immunoglobulin G were evaluated by an enzyme linked immunosorbent assay. The protease fraction was detected by Sephadex G 150 chromatography. The results showed that A. actinomycetemcomitans produced a protease to human immunoglobulin G in the culture supernatant, and the highest activity was achieved witen the concentration was 27.5 mug protein/mL, after culturing for 72 hours and incubating with IgG for 24 hours. The molecular mass of the protease active fraction was from 43 to 150 kDa.Actinobacillus actinomycetemcomitans produz protease ativa sobre imunoglobulina G humana, sendo um dos mecanismos importantes de escape do microrganismo. No presente trabalho, foi analisada a atividade proteolítica de sobrenadante de cultivo de A. actinomycetemcomitans ATCC 43718 sobre imunoglobulina G humana em função de concentração, tempo de cultivo do microrganismo e tempo de incubação com IgG, por ensaio imunoenzimático. Adicionalmente, foi determinada a fração com atividade de protease por meio de análise de eluatos de cromatografia em coluna de Sephadex G 150. Os resultados obtidos demonstraram que A. actinomycetemcomitans liberou protease ativa sobre imunoglobulina G humana em sobrenadante de cultivo, sendo a sua maior atividade evidenciada na concentração de 27,5 mig proteína/mL, com tempo de cultivo de 72 horas e com 24 horas de incubação com IgG. A massa molecular da fração ativa de protease foi compreendida entre 43 a 150 kDa.
Wang, Shuai; Yang, Yanbei; Zhao, Yulin; Zhao, Honghai; Bai, Jingwen; Chen, Jianqing; Zhou, Yonghui; Wang, Chang; Li, Yanhua
Streptococcus suis (S.suis) is an important zoonotic pathogen that causes severe diseases in humans and pigs. Biofilms of S. suis can induce persistent infections that are difficult to treat. In this study, the effect of tylosin on biofilm formation of S. suis was investigated. 1/2 minimal inhibitory concentration (MIC) and 1/4 MIC of tylosin were shown to inhibit S. suis biofilm formation in vitro. By using the iTRAQ strategy, we compared the protein expression profiles of S. suis grown with sub-MIC tylosin treatment and with no treatment. A total of 1501 proteins were identified by iTRAQ. Ninety-six differentially expressed proteins were identified (Ratio > ±1.5, p MIC tylosin treatment. Thus, our data revealed the rough regulation of biofilm formation that may provide a foundation for future research into mechanisms and targets.
Full Text Available Brucella species are the most important zoonotic pathogens worldwide and cause considerable harm to humans and animals. In this study, we presented the complete genome of B. suis 019 isolated from sheep (ovine with epididymitis. B. suis 019 has a rough phenotype and can infect sheep, rhesus monkeys and possibly humans. The comparative genome analysis demonstrated that B. suis 019 is closest to the vaccine strain B. suis bv. 1 str. S2. Further analysis associated the rsh gene to the pathogenicity of B. suis 019, and the WbkA gene to the rough phenotype of B. suis 019. The 019 complete genome data was deposited in the GenBank database with ID PRJNA308608.
Sheinman, B D; Devalia, J L; Davies, R J; Crook, S J; Tabaqchali, S
Recent findings suggest that bacteria might contribute to histamine concentrations in the sputum of patients with infective lung disease. Ten isolates of Haemophilus influenzae from patients with acute exacerbation of chronic bronchitis and emphysema, together with two reference strains, were incubated at 37 degrees C for 72 hours. Serial estimations of histamine concentrations by high pressure liquid chromatography showed significant increases at 24 and 48 hours; no increases were evident in the control samples. These findings suggest that H influenzae might contribute to inflammation and limited airflow in infective lung disease by producing histamine.
Hsu, Meng-Shiuan; Wu, Mei-Yu; Lin, Tsui-Hsien; Liao, Chun-Hsing
Haemophilus parainfluenzae is a common inhabitant of the human upper respiratory tract of the normal oral microflora. We report three men who had been having unprotected sex with men (MSM) and subsequently acquired H. parainfluenzae urethritis, which was confirmed by 16S rRNA gene sequencing analysis. Two men were treated with ceftriaxone and doxycycline, and the third man was treated with clarithromycin. All three patients responded to treatment. This case series highlights the potential role of H. parainfluenzae as a sexually transmitted genitourinary pathogen.
Setlow, J.K.; McCarthy, D.R.; Clayton, N.L.
A gene library of Haemophilus influenzae DNA has been constructed by ligating chromosomal DNA from cells resistant to a number of antibiotics, together with DNA of the H. influenzae plasmid RSF0885. Before ligation both DNAs were cut with the enzyme PvuII. The ligated DNA was allowed to enter competent H. influenzae sensitive to the antibiotics and selection was made for resistance to ampicillin, conferred by the plasmid RSF0885 DNA. Plasmids conferring resistance to various other antibiotics, as well as to ampicillin, have been obtained by this procedure and subsequent selection for chromosomal markers.
Schnell, Martin W
Self care is an answer to the response of finiteness, which is given through the fact of the human body. The article demonstrates in reference to the Selfcaredeficit-Theory (Orem, 2006) how self care in everyday life, ancient roman called it cura sui, is related to nursing practice, specially to acutecare. Self care turns out as an category of ambivalence between ethics and power.
LI Pengli; WEI Wu; LI Yixue; MA Yuanyuan; DING Guohui; LI Xiaoping; WANG Xiaojing; ZHANG Liwen; SUN Jingchun; WANG Yong; TU Kang; WANG Ningning; HAO Pei; WANG Chuan; CAO Zhiwei; SHI Tieliu
The outbreak of Streptococcus suis recently in some districts of Sichuan Province in China has caused over 30 deaths and over 200 infections in human beings. In order to study the pathogenicity mechanism and to prevent the bacteria from spreading and infecting human beings and swine, we have annotated and analyzed the genomes of two strains, Streptococcus suis P1/7 and 89-1591 respectively. The whole length of P1/7 is 2.007 Mb,and has 1969 ORFs. In contrast, the partial genome sequence of 89-1591 is 1.98 Mb in length and exists in 177 contigs with 1918 ORFs. Analysis shows that the average lengths of CDSs in two genomes are very close, and the numbers of the homolog ORFs are 1306 between those two strains. Most of the toxicity factors of the two strains are homologeous, but there are still some significant differences between those two strains. For example, among the 11 genes (cps2A-cps2K) encoding for the capsules in P1/7, 4(cps2A, 2B, 2I, 2J) are not detected in strain 89-1591.At the same time, the genes encoding EF and Haemolysin in P1/7 are also not found in strain 89-1591. Besides, the genes related to DNA replication, repair and recombination differ from each other significantly and there also exist certain differences among the surface proteins. Those characteristics indicate that those two strains have evolved their own specific functions to adapt to the different environments and that the pathogenesis of the two strains is different. We have accumulated comprehensive genomics information for future systematic studies of S.sui. Our results are helpful for disease prevention,vaccine development, as well as drug design for S.suis.
Full Text Available The existence of the Geographical Indication (GI was estabilished at the same time as the TRIPs Agreement in 1994. In the TRIPs Agreement, GI is Intellectual Property Rights (hereafter IPR regime that is typical of sui generis due to its distinctive features. It is reflected in the elements that are in the definition of GI. Basically, GI has set the use of Geographical names to recognise an object. Previously, the IPR regime had also set them, namely: Indication of Source (IS and Apellation of Origin (AO, that were set in the Paris Convention in 1883, Madrid Agreement in 1891, and the Lisbon Agreement in 1958. Instead, the geographical names are also used as brands. The paper is a theoretical study towards two problems. First, the elements that become the characteristics of GI so that it is typical of sui generis. Second, the similiarities and the differences amongst GI and IS, AO and other trademarks. The findings of the study reveal that GI is typical of sui generis, reflected in the elements that are in the GI definition as it has already been agreed upon in the TRIPs Agreement. There are similiarities amongst GI and AS, AO and other trademarks, namely they can use the geographical names as a label on objects. Meanwhile, the differences are in the elements themselves. IS has the simplest element, followed by GI and the trademark is in ownership system that is individual in the trademark and communal in GI.
Full Text Available It’s cannot deny that intellectual property right laws, in certain aspects are possible for using to protect traditional knowledge from their utilization. However, in the same time, intelectuual property rezim also become “a tool” to legitimate of biopiracy practices. Due to the massive of international pressure, mostly developing countries, and the awereness that intellectual property regimes doesn’t optimal to protect traditional knowledge, it develops a discourse to develop a sui generis law outside of intellectual property right regimes. By using the normative method and qualitative approach, this research shows that in order to develop the sui generis law in Indonesia, there are several minimum elements that shall be contained in it, inter alia: the purposes of protection; scope of protection; creteria of protection; the beneficiaries of protection: the holder of traditional knowledge; the kind of rights to be granted; how does the rights acquired; how to enforce it; how does the rights lost or expired; and dispute resolution.Keywords: protection, traditional knowledge, sui generis law
Sánchez, J M; Zurro, F J; Ferreiro, D; Llana, R; Uría, D F
We present 2 cases of Haemophilus influenzae meningitis. The first is a patient with atypical simptomatology: abdominal pain, fever and two days later pain in the back of his legs. Abdominal pathology was not found. The cerebrospinal fluid (CSF) showed polymorphonuclear cells, hyperproteinorachia and lowered glucose. CSF culture revealed Haemophilus influenzae, blood culture was sterile. The second had suffered surgery at maxilar and ethmoid sinuses four years before, and unknown germ meningitis 6 months before. Haemophilus influenzae was isolated from CSF cultures and CSF rhinorrhea was detected by isotopic cisternography.
Full Text Available Entre las bacterias relacionadas con la enfermedad periodontal, existen dos especies más claramente asociadas a esta enfermedad: Actinobacillus actinomycetemcomitans y Porphyromonas gingivalis. Este trabajo es una revisión bibliográfica sobre estos dos patógenos periodontales, mostrando su origen, prevalencia, distribución, transmisión y respuesta al tratamiento periodontal.Among the bacteria related to periodontal disease, there are two species clearly associated to this disease: Actinobacillus actinomycetemcomitans and Porphyromonas gingiva lis. This paper presents a review of the literature regarding this two periodontal pathogens, and showing their origin, prevalence, distribution, transmission and response to periodontal treatment.
Leaves, N I; Anderson, E C; Toy, S J
Outer membrane protein profiling was used to assist in determining the identity of an isolate of Haemophilus spp. that was presumptively identified as non-capsulate Haemophilus influenzae biotype III. The possibility that this strain was in fact Haemophilus aegyptius was queried because of clinical information and the source of the isolate. Sodium dodecyl-sulphate polyacrylamide gel electrophoresis was used to establish the identity of the isolate as non-capsulate H. influenzae biotype III and no H. aegyptius. Generally, protein profiling compared very favourably with other standard tests for identifying H. aegyptius: the method was easily and rapidly performed and gave an unequivocal result.
Karwacki, Michael T.; Kadouri, Daniel E.; Bendaoud, Meriem; Izano, Era A.; Sampathkumar, Vandana; Inzana, Thomas J.; Kaplan, Jeffrey B.
Cell-free extracts isolated from colony biofilms of Actinobacillus pleuropneumoniae serotype 5 were found to inhibit biofilm formation by Staphylococcus aureus, S. epidermidis and Aggregatibacter actinomycetemcomitans, but not by A. pleuropneumoniae serotype 5 itself, in a 96-well microtiter plate assay. Physical and chemical analyses indicated that the antibiofilm activity in the extract was due to high-molecular-weight polysaccharide. Extracts isolated from a mutant strain deficient in the production of serotype 5 capsular polysaccharide did not exhibit antibiofilm activity. A plasmid harboring the serotype 5 capsule genes restored the antibiofilm activity in the mutant extract. Purified serotype 5 capsular polysaccharide also exhibited antibiofilm activity against S. aureus. A. pleuropneumoniae wild-type extracts did not inhibit S. aureus growth, but did inhibit S. aureus intercellular adhesion and binding of S. aureus cells to stainless steel surfaces. Furthermore, polystyrene surfaces coated with A. pleuropneumoniae wild-type extracts, but not with capsule-mutant extracts, resisted S. aureus biofilm formation. Our findings suggest that the A. pleuropneumoniae serotype 5 capsule inhibits cell-to-cell and cell-to-surface interactions of other bacteria. A. pleuropneumoniae serotype 5 capsular polysaccharide is one of a growing number of bacterial polysaccharides that exhibit broad-spectrum, nonbiocidal antibiofilm activity. Future studies on these antibiofilm polysaccharides may uncover novel functions for bacterial polysaccharides in nature, and may lead to the development of new classes of antibiofilm agents for industrial and clinical applications. PMID:23691104
Michael T Karwacki
Full Text Available Cell-free extracts isolated from colony biofilms of Actinobacillus pleuropneumoniae serotype 5 were found to inhibit biofilm formation by Staphylococcus aureus, S. epidermidis and Aggregatibacter actinomycetemcomitans, but not by A. pleuropneumoniae serotype 5 itself, in a 96-well microtiter plate assay. Physical and chemical analyses indicated that the antibiofilm activity in the extract was due to high-molecular-weight polysaccharide. Extracts isolated from a mutant strain deficient in the production of serotype 5 capsular polysaccharide did not exhibit antibiofilm activity. A plasmid harboring the serotype 5 capsule genes restored the antibiofilm activity in the mutant extract. Purified serotype 5 capsular polysaccharide also exhibited antibiofilm activity against S. aureus. A. pleuropneumoniae wild-type extracts did not inhibit S. aureus growth, but did inhibit S. aureus intercellular adhesion and binding of S. aureus cells to stainless steel surfaces. Furthermore, polystyrene surfaces coated with A. pleuropneumoniae wild-type extracts, but not with capsule-mutant extracts, resisted S. aureus biofilm formation. Our findings suggest that the A. pleuropneumoniae serotype 5 capsule inhibits cell-to-cell and cell-to-surface interactions of other bacteria. A. pleuropneumoniae serotype 5 capsular polysaccharide is one of a growing number of bacterial polysaccharides that exhibit broad-spectrum, nonbiocidal antibiofilm activity. Future studies on these antibiofilm polysaccharides may uncover novel functions for bacterial polysaccharides in nature, and may lead to the development of new classes of antibiofilm agents for industrial and clinical applications.
Vanni, Michele; Merenda, Marianna; Barigazzi, Giuseppe; Garbarino, Chiara; Luppi, Andrea; Tognetti, Rosalba; Intorre, Luigi
The aim of this retrospective study was to evaluate the antimicrobial resistance rates and the trend in resistance of Actinobacillus pleuropneumoniae isolated from pigs in Italy from 1994 to 2009. A total of 992 A. pleuropneumoniae isolates were tested for their susceptibility to a panel of antimicrobial agents in a disk diffusion method. Resistance to 7 drugs (amoxicillin, amoxicillin/clavulanic acid, ampicillin, cefquinome, cotrimoxazole, penicillin G and tilmicosin) showed a significant increasing trend over the time, while for 2 drugs (gentamycin and marbofloxacin) a significant decrease was observed. Resistance to the remaining 14 antimicrobial agents tested did not change significantly over the study period. Most of the isolates retained high susceptibility to antimicrobials usually effective against A. pleuropneumoniae such as amphenicols, fluoroquinolones and ceftiofur. However, high rates of resistance were observed for potentiated sulfa drugs, tetracyclines and penicillins which are currently recommended antimicrobials for pig pleuropneumonia therapy. Our results suggest the importance of continued monitoring of A. pleuropneumoniae clinical isolates in order to choose the most appropriate treatment of infections and to control the increase of resistance to currently used antimicrobials. Copyright Â© 2011 Elsevier B.V. All rights reserved.
Loera-Muro, Victor M; Jacques, Mario; Tremblay, Yannick D N; Avelar-González, Francisco J; Loera Muro, Abraham; Ramírez-López, Elsa M; Medina-Figueroa, Alejandra; González-Reynaga, Higinio M; Guerrero-Barrera, Alma L
Actinobacillus pleuropneumoniae is the aetiological agent of porcine pleuropneumonia and is normally transmitted by aerosols and direct contact between animals. A. pleuropneumoniae has traditionally been considered an obligate pathogen of pigs and its presence in the environment has yet to be investigated. Here, the presence of A. pleuropneumoniae was detected in drinking water of pig farms in Mexico using a PCR specific for the RTX toxin gene, apxIV. The presence of A. pleuropneumoniae in farm drinking water was confirmed by indirect immunofluorescence using an A. pleuropneumoniae-specific polyclonal antibody and by fluorescent in situ hybridization. Viable bacteria from the farm drinking water were detected using the Live/Dead BacLight stain. Additionally, viable A. pleuropneumoniae was selected and isolated using the cAMP test and the identity of the isolated bacteria were confirmed by Gram staining, a specific polyclonal antibody and an A. pleuropneumoniae-specific PCR. Furthermore, biofilms were observed by scanning electron microscopy in A. pleuropneumoniae-positive samples. In conclusion, our data suggest that viable A. pleuropneumoniae is present in the drinking water of swine farms and may use biofilm as a strategy to survive in the environment.
Full Text Available Abstract Background Actinobacillus pleuropneumoniae (APP is one of the most important swine pathogens worldwide. Identification and characterization of novel antigenic APP vaccine candidates are underway. In the present study, we use an immunoproteomic approach to identify APP protein antigens that may elicit an immune response in serotype 1 naturally infected swine and serotype 1 virulent strain S259-immunized rabbits. Results Proteins from total cell lysates of serotype 1 APP were separated by two-dimensional electrophoresis (2DE. Western blot analysis revealed 21 immunoreactive protein spots separated in the pH 4-7 range and 4 spots in the pH 7-11 range with the convalescent sera from swine; we found 5 immunoreactive protein spots that separated in the pH 4-7 range and 2 in the pH 7-11 range with hyperimmune sera from S259-immunized rabbits. The proteins included the known antigens ApxIIA, protective surface antigen D15, outer membrane proteins P5, subunit NqrA. The remaining antigens are being reported as immunoreactive proteins in APP for the first time, to our knowledge. Conclusions We identified a total of 42 immunoreactive proteins of the APP serotype 1 virulent strain S259 which represented 32 different proteins, including some novel immunoreactive factors which could be researched as vaccine candidates.
Alsina, M; Olle, E; Frias, J
Actinobacillus actinomycetemcomitans is considered to be one of the major oral putative pathogens, especially in cases of juvenile periodontitis. This microorganism requires nutritionally complex media for growth, and therefore the media for its primary isolation usually include blood agar or serum in their base. In this study we present a new medium, Dentaid-1, which improves the detection of A. actinomycetemcomitans in periodontal samples. In its composition, blood and serum have been omitted, hence reducing its cost and making it a more restrictive medium against the growth of other microorganisms with high nutritional requirements. The growth yields of pure cultures of the bacteria on Dentaid-1 were comparable to those on nonselective blood agar. Moreover, clinical efficacy was evaluated in subgingival samples from 77 subjects with adult periodontitis. Dentaid-1 detected A. actinomycetemcomitans in 24 subjects, while a previously described tryptic soy-serum-bacitracin-vancomycin agar detected the microorganism in only 19 subjects (79.1%). Dentaid-1 is a low-cost, noninhibitory formula for the improved diagnosis and monitoring of patients subgingivally infected by this important oral putative pathogen.
Miyasaki, K T; Wilson, M E; Brunetti, A J; Genco, R J
Actinobacillus actinomycetemcomitans is a facultative gram-negative microorganism which has been implicated as an etiologic agent in localized juvenile periodontitis and in subacute bacterial endocarditis and abscesses. Although resistant to serum bactericidal action and to oxidant injury mediated by superoxide anion (O2-) and hydrogen peroxide (H2O2), this organism is sensitive to killing by the myeloperoxidase-hydrogen peroxide-chloride system (K.T. Miyasaki, M.E. Wilson, and R.J. Genco, Infect. Immun. 53:161-165, 1986). In this study, we examined the sensitivity of A. actinomycetemcomitans to killing by intact neutrophils under aerobic conditions, under anaerobic conditions, and under aerobic conditions in the presence of the heme-protein inhibitor sodium cyanide. Intact neutrophils killed opsonized A. actinomycetemcomitans under aerobic and anaerobic conditions, and the kinetics of these reactions indicated that both oxidative and nonoxidative mechanisms were operative. Oxidative mechanisms contributed significantly, and most of the killing attributable to oxidative mechanisms was inhibited by sodium cyanide, which suggested that the myeloperoxidase-hydrogen peroxide-chloride system participated in the oxidative process. We conclude that human neutrophils are capable of killing A. actinomycetemcomitans by both oxygen-dependent and oxygen-independent pathways, and that most oxygen-dependent killing requires myeloperoxidase activity.
Full Text Available Catecholamines are host stress hormones that can induce the growth of many bacteria by facilitating iron utilization and/or regulate the expression of virulence genes through specific hormone receptors. Whether these two responsive pathways are interconnected is unknown. In our previous study, it was found that catecholamines can regulate the expression of a great number of genes of Actinobacillus pleuropneumoniae, an important swine respiratory pathogen. However, bacterial growth was not affected by catecholamines in rich medium. In this study, it was discovered that catecholamines affected A. pleuropneumoniae growth in chemically defined medium (CDM. We found that serum inhibited A. pleuropneumoniae growth in CDM, while epinephrine, norepinephrine and dopamine promoted A. pleuropneumoniae growth in the CDM containing serum. The known bacterial hormone receptor QseC didn't play roles in this process. Ion-supplementation and transcriptome analysis indicated that serum addition resulted in iron-restricted conditions which were alleviated by the addition of catecholamines. Transferrin, one of the components in serum, inhibited the growth of A. pleuropneumoniae in CDM, an effect reversed by addition of catecholamines in a TonB2-dependent manner. Our data demonstrate that catecholamines promote A. pleuropneumoniae growth by regulating iron-acquisition and metabolism, which is independent of the adrenergic receptor QseC.
Li, Lu; Chen, Zhaohui; Bei, Weicheng; Su, Zhipeng; Huang, Qi; Zhang, Liang; Chen, Huanchun; Zhou, Rui
Catecholamines are host stress hormones that can induce the growth of many bacteria by facilitating iron utilization and/or regulate the expression of virulence genes through specific hormone receptors. Whether these two responsive pathways are interconnected is unknown. In our previous study, it was found that catecholamines can regulate the expression of a great number of genes of Actinobacillus pleuropneumoniae, an important swine respiratory pathogen. However, bacterial growth was not affected by catecholamines in rich medium. In this study, it was discovered that catecholamines affected A. pleuropneumoniae growth in chemically defined medium (CDM). We found that serum inhibited A. pleuropneumoniae growth in CDM, while epinephrine, norepinephrine and dopamine promoted A. pleuropneumoniae growth in the CDM containing serum. The known bacterial hormone receptor QseC didn't play roles in this process. Ion-supplementation and transcriptome analysis indicated that serum addition resulted in iron-restricted conditions which were alleviated by the addition of catecholamines. Transferrin, one of the components in serum, inhibited the growth of A. pleuropneumoniae in CDM, an effect reversed by addition of catecholamines in a TonB2-dependent manner. Our data demonstrate that catecholamines promote A. pleuropneumoniae growth by regulating iron-acquisition and metabolism, which is independent of the adrenergic receptor QseC.
Murphy, T.F.; Brauer, A.L.; Sethi, S.
Background. Haemophilus influenzae is a common pathogen in adults with chronic obstructive pulmonary disease (COPD). In a prospective study, selected isolates of apparent H. influenzae had an altered phenotype. We tested the hypothesis that these variant strains were genetically different from ty...... distinguish H. haemolyticus from H. influenzae. H. haemolyticus is a respiratory tract commensal. The recognition that some strains of apparent H. influenzae are H. haemolyticus substantially strengthens the association of true H. influenzae with clinical infection....
Carlone, G M; Sottnek, F O; Plikaytis, B D
Haemophilus aegyptius and Haemophilus influenzae biotype III are morphologically and biochemically similar; however, their outer membrane protein (Sarkosyl insoluble) profiles are distinct. Of 18 strains of H. aegyptius examined, 15 had a type 1 protein profile, and 3 had a type 2 profile, whereas the 5 strains of H. influenzae biotype III examined had three other protein profile types. All Haemophilus strains examined had 31- and 76-kilodalton (kDa) proteins and minor proteins with molecular masses between 20 and 100 kDa. H. aegyptius, with a type 1 protein profile, had major outer membrane proteins with apparent molecular masses of 27, 35.5, and 41.5 kDa, and H. aegyptius, with a type 2 protein profile, had 26-, 29-, 39.5-, and 41-kDa proteins. The type strain of H. influenzae biotype III had three major outer membrane proteins with apparent molecular masses of 29, 38.5 and 40 kDa. Four other strains designated as H. influenzae biotype III had major outer membrane proteins between 27 and 41.5 kDa representing two additional protein profiles.
Marraro, R V; McCleskey, F K; Mitchell, J L
Haemophilus influenzae (H. aegyptius) biotype 3 was isolated from eye, nasopharyngeal, and sputum cultures of a 23-month-old male and from sputum and transtracheal aspirate cultures of his 39-year-old mother, both with diffuse bronchopneumonia.
Baums, C G; Da Silva, L M; Goethe, R; Valentin-Weigand, P
Streptococcus suis (Sc. suis) can cause very different clinical entities. In contrast to Sc. suis-associated pneumonia, the induction of meningitis, septicemia, and polyarthritis by certain Sc. suis strains requires the expression of virulence factors that contribute to the invasiveness of the pathogen. In the presented study, we examined the occurrence of known virulence-associated factors in Sc. suis isolates from samples sent to the Institute of Microbiology, School of Veterinary Medicine Hannover, in order to evaluate their significance as potential virulence factors in different disease complexes in Northern Germany. The results show that (i) MRP + EF + serotype 2 and MRP* EF-serotype 9 strains are statistically significant associated with the disease complex meningitis/septicemia/arthritis and, thus, have to be considered invasive strains, (ii) serotyping alone is not sufficient for identification of virulent strains, (iii) there is a remarkable heterogeneity among pneumonia-associated Sc. suis strains and (iv) activity of haemolysin or suilysin appears to be not appropriate as virulence marker. Finally, it has to be noted that at present only half of the Sc. suis isolates from pigs with meningitis/septicemia/poyarthritis can be characterised by the detection of virulence-associated factors. Thus, the identification and characterisation of additional, serotype independent virulence factors of Sc. suis is a very important issue in future studies.
Koczula, A; Willenborg, J; Bertram, R; Takamatsu, D; Valentin-Weigand, P; Goethe, R
The lack of knowledge about pathogenicity mechanisms of Streptococcus (S.) suis is, at least partially, attributed to limited methods for its genetic manipulation. Here, we established a Cre-lox based recombination system for markerless gene deletions in S. suis serotype 2 with high selective pressure and without undesired side effects.
Full Text Available Streptococcus suis is a swine pathogen and also a zoonotic agent. The formation of bioﬁlms allows S. suis to become persistent colonizers and resist clearance by the host immune system and antibiotics. In this study, biofilm forming potentials of various S. suis strains were characterized by confocal laser scanning microscopy (CLSM, scanning electron microscopy (SEM and tissue culture plates stained with crystal violet. In addition, the effects of five antimicrobial agents on biofilm formation were assayed in this study. S. suis produced biofilms on smooth and rough surface. The nutritional contents including glucose and NaCl in the growth medium modulated biofilm formation. There was a significant difference in their biofilm-forming ability among all 46 S. suis strains. The biofilm-forming potential of S. suis serotype 9 was stronger than type 2 and all other types. However, biofilm formation was inhibited by five commonly used antimicrobial agents, penicillin, erythromycin, azithromycin, ciprofloxacin, and ofloxacin at subinhibitory concentrations, among which inhibition of ciprofloxacin and ofloxacin was stronger than that of other three antimicrobial agents.Our study provides a detailed analysis of biofilm formation potential in S. suis, which is a step towards understanding its role in pathogenesis, and eventually lead to a better understanding of how to eradicate S. suis growing as biofilms with antibiotic therapy.
Wang, K.; Weixing, Fan; Wisselink, H.J.; Chengping, Lu
Streptococcus suis serotype 16 can infect pigs and humans. We describe the identification and the characterization of the capsular polysaccharides synthesis locus of S. suis serotype 16. Using PCR primers flanking the capsular polysaccharides synthesis locus, a 30,101-bp fragment was amplified. Twen
Ferrando, Maria Laura; de Greeff, Astrid; van Rooijen, Willemien J. M.;
Background. Streptococcus suis has emerged as an important cause of bacterial meningitis in adults. The ingestion of undercooked pork is a risk factor for human S. suis serotype 2 (SS2) infection. Here we provide experimental evidence indicating that the gastrointestinal tract is an entry site of...
Segura, M.; Zheng, H.; Greeff, de A.; Gao, G.F.; Gremier, D.; Jiang, Y.; Chengping, L.; Maskell, D.; Oishi, K.; Okura, M.; Osawa, R.; Schultsz, C.; Schwerk, C.; Sekizaki, T.; Smith, H.; Srimanote, P.; Takamatsu, D.; Tang, J.; Tenenbaum, T.; Tharavichitkul, P.; Hoa, N.T.; Valentin-Weigand, P.; Wells, J.M.; Wertheim, H.; Zhu, B.; Xu, J.; Gottschalk, M.
This second and final chapter of the report on the First International Workshop on Streptococcus suis follows on from Part 1, published in the April 2014, volume 9, issue 4 of Future Microbiology. S. suis is a swine pathogen and a zoonotic agent afflicting people in close contact with infected pigs
Streptococcus suis is Gram-positive bacterium and its natural habitat is the upper respiratory tract of pigs, and in particular the tonsils and nasal cavity. Although it is considered to be a normal member of the adult pig microbiome, it can cause serious diseases in pigs and humans. S. suis is in f
Andreasen, Annette; Petersen, Heidi Huus; Kringel, Helene;
The aim of the present study was to investigate parasite induced immune responses in pigs co-infected with Trichuris suis and Oesophagostomum dentatum as compared to mono-species infected pigs. T. suis is known to elicit a strong immune response leading to rapid expulsion, and a strong antagonist...
Ferrando, Maria Laura; Willemse, Niels; Zaccaria, Edoardo; Pannekoek, Yvonne; Ende, van der Arie; Schultsz, Constance
Background Streptococcus suis is a zoonotic pathogen, causing meningitis and septicemia. We previously demonstrated that the gastrointestinal tract (GIT) is an entry site for zoonotic S. suis infection. Here we studied the contribution of Streptococcal adhesin Protein (SadP) to hostpathogen
Hansen, Tina Vicky Alstrup; Friis, Christian; Nejsum, Peter;
It is recognized that the clinical efficacy of single dose benzimidazoles (BZs) against the nematode, Trichuris suis of pigs and the closely related Trichuris trichiura in humans is only poor to moderate. Recent in vitro studies have indicated that a low uptake of fenbendazole (FBZ) in T. suis may...
Wichgers Schreur, P.J.; Rebel, J.M.J.; Smits, M.A.; Putten, van J.P.M.; Smith, H.E.
Streptococcus suis causes infections in pigs and occasionally in humans resulting in 23 manifestations as meningitis, sepsis, arthritis and septic shock. For survival within the 24 host, S. suis requires numerous nutrients including trace metals. Little is known about 25 the specific proteins involv
ZHANG Chun-ping; NING Yi-bao; ZHANG Zhong-qiu; SONG Li; QIU Hui-shen; GAO He-yi; FAN Xue-zheng
Streptococcus suis is an important pathogen in pigs.Transmission of this pathogen is generally believed to occur between healthy carrier sows and their offspring,so the carrier status orS.suis in healthy sows is important for the control of S.suis infections in pigs,especially in suckling and growing pigs.In this study,the prevalence orS.suis isolated from clinically healthy sows in China was studied for the first time.A total of 1043 tonsil samples were collected from clinically healthy sows from 10 regions in China from 2005 to 2007.Among the 421 S.suis isolates,31 strains were identified as capsular type 2.The results showed that S.suis was widespread in swine herds in China with the carrier rates in different herds ranging from 19.5 to 93.9%.Overall,40.4 and 3.0% of clinically healthy sows harbored S.suis and capsular type 2 in their palatine tonsils,respectively.Statistically significant differences of carrier rates of S.suis and capsular type 2 between the different farms were observed,which was independent of herd sizes and geographic distributions of different herds.
Full Text Available Streptococcus suis, more particularly serotype 2, is a major swine pathogen and an emerging zoonotic agent worldwide that mainly causes meningitis, septicemia, endocarditis, and pneumonia. Although several potential virulence factors produced by S. suis have been identified in the last decade, the pathogenesis of S. suis infections is still not fully understood. In the present study, we showed that S. suis produces membrane vesicles (MVs that range in diameter from 13 to 130 nm and that appear to be coated by capsular material. A proteomic analysis of the MVs revealed that they contain 46 proteins, 9 of which are considered as proven or suspected virulence factors. Biological assays confirmed that S. suis MVs possess active subtilisin-like protease (SspA and DNase (SsnA. S. suis MVs degraded neutrophil extracellular traps, a property that may contribute to the ability of the bacterium to escape the host defense response. MVs also activated the nuclear factor-kappa B (NF-κB signaling pathway in both monocytes and macrophages, inducing the secretion of pro-inflammatory cytokines, which may in turn contribute to increase the permeability of the blood brain barrier. The present study brought evidence that S. suis MVs may play a role as a virulence factor in the pathogenesis of S. suis infections, and given their composition be an excellent candidate for vaccine development.
Zhang, Rui-xian; Lu, Qin; Zhang, Wei; Zhang, Mu-qun
Although there were changes in measuring system of Sui dynasty, the measuring units of medicine, astronomy and music still remained unchanged. So there appeared two systems of measuring units. For medicine, the government of Tang dynasty followed the regulations of Sui dynasty in measuring system. Besides this, the measuring units of Qian and Fen also were also related to medicine.
Aksoycan, N; Sağanak, I; Wells, G
The immune sera for Brettanomyces lambicus, B. claussenii, Debaryomyces hansenii and D. marama agglutinated Salmonella cholerae-suis (0:6(2), 7). The immune serum for S. cholerae-suis agglutinated B. lambicus, B. clausenni, D. hansenii and D. marama. Absorption and agglutination cross-tested demonstrated common antigen factor(s) in the tested yeasts and Salmonella 0:7 antigen.
Holden, M.T.G.; Hauser, H.; Sanders, M.; Hoa Ngo, Thi; Cherevach, I.; Cronin, A.; Goodhead, I.; Mungall, K.; Quail, M.A.; Price, C.; Rabbinowitsch, E.; Sharp, S.; Croucher, N.; Chieu, Tran Bich; Nguyen, Thi Hoang Mai; To, Song Diep; Nguyen, Tran Chinh; Kehoe, M.; Leigh, J.A.; Ward, P.N.; Dowson, C.G.; Whatmore, A.M.; Chanter, N.; Iversen, P.; Gottschalk, M.; Slater, J.D.; Smith, H.E.; Spratt, B.G.; Jianguo, Xu; Changyun, Ye; Bentley, S.; Barrell, B.G.; Schultsz, C.; Maskell, D.J.; Parkhill, J.
Background - Streptococcus suis is a zoonotic pathogen that infects pigs and can occasionally cause serious infections in humans. S. suis infections occur sporadically in human Europe and North America, but a recent major outbreak has been described in China with high levels of mortality. The mechan
Madsen, L.W.; Boye, Mette; Jensen, Henrik E
A method for enzyme-based in situ hybridisation of Streptococcus suis was developed. It enables the light microscopic localization of bacterial ribosomal RNA (rRNA) in formalin-fixed paraffin-embedded tissues. A unique sequence in the 16S rRNA of S. suis was targeted. Different pretreatment...
Full Text Available Chancroid is a sexually transmitted infection caused by Haemophilus ducreyi. This fastidious, Gram-negative coccobacilli dies rapidly outside the human host, making diagnostic testing using culture methods difficult. This genital ulcer infection is not common in Canada and, therefore, can often be misdiagnosed. The objective of the present paper is to provide practical approaches for the diagnosis of chancroid in Canadian patients where the prevalence of this infection is low. Issues related to sample collection, sample transport and available diagnostic tests are reviewed, and several alternative approaches are outlined. Although antigen detection, serology and genetic amplification methods have all been reported for H ducreyi, none are commercially available. Culture is still the primary method available to most laboratories. However, the special media necessary for direct bedside inoculation is often not available; therefore, communication with the diagnostic laboratory and rapid specimen transport are essential when chancroid is suspected
Tobias, T.J.; Bouma, A.; Broek, van den J.; Nes, van A.; Daemen, A.J.J.M.; Wagenaar, J.A.; Stegeman, J.A.; Klinkenberg, D.
Clinical outbreaks due to Actinobacillus pleuropneumoniae occur recurrently, despite the wide-scale use of antimicrobials or vaccination. Therefore, new approaches for the prevention and control of these outbreaks are necessary. For the development of alternative measures, more insight into the tran
Lauritzen, B.; Lykkesfeldt, J.; Skaanild, M.T.
Biomarkers of infection were screened for their possible role as evaluators of antibiotic treatment in an aerosol infection model of porcine pneumonia caused by Actinobacillus pleuropneumoniae (Ap). Following infection of 12 pigs, clinical signs of pneumonia developed within 20 h, whereafter...
Schuchert, J.A.; Inzana, T.J.; Angen, Øystein
Multiplex PCR assays were developed to identify Actinobacillus pleuropneumoniae serotypes 1, 2, and 8. Primers designed for the conserved capsular polysaccharide (CP) export region amplified a 489-bp DNA fragment from all serotypes. Primers specific to the CP biosynthesis regions of serotypes 1, 2...
Jirawattanapong, P.; Stockhofe-Zurwieden, N.; Leengoed, van L.A.M.G.; Binnendijk, G.P.; Wisselink, H.J.; Raymakers, R.; Cruijsen, T.; Peet-Schwering, van der C.M.C.; Nes, van A.; Nielen, M.
Objective: To evaluate lung lesions at slaughter after three-dose vaccination with a subunit Actinobacillus pleuropneumoniae vaccine containing ApxI, ApxII, ApxIII, and an outer membrane protein. Materials and methods: A total of 430 newborn piglets in a herd endemically infected with A
Nielsen, R.; Andresen, Lars Ole; Plambeck, Tamara
Eight Actinobacillus pleuropneumoniae biotype 2 strains were isolated in pure culture from lungs of pigs originating from two Danish herds with growing and finishing pigs. The antigenic properties were studied by indirect haemagglutination (IHA) and immunodiffusion (ID) tests using soluble surface...
Boekema, B.K.H.L.; Stockhofe, N.; Smith, H.E.; Kamp, E.M.; Putten, van J.P.; Verheijden, J.H.
To study adherence of Actinobacillus pleuropneumoniae to porcine lower respiratory epithelium, a cell culture model was developed using primary cultures of porcine lung epithelial cells (LEC). Adherence assays were performed and results were compared with data obtained with swine kidney cells (SK6).
Velthuis, A.G.J.; Jong, de M.C.M.; Stockhofe, N.; Vermeulen, T.M.M.; Kamp, E.M.
Ten transmission trials with Actinobacillus pleuropneumoniae were carried out. The observed transmission was highly variable, which was surprising since the design of the trials was very similar. We investigated whether the variable transmission could be explained by variation in infectivity of A.
Haubek, Dorte; Ennibi, O.-K.; Poulsen, Knud
A particular clone (JP2) of Actinobacillus actinomycetemcomitans with increased leukotoxin production has been isolated from individuals with early-onset periodontitis (EOP). The aim of this study was to determine the frequency of carriers of this clone and its association with EOP in Moroccan...
Groenink, J; Walgreen-Weterings, E; Nazmi, K; Bolscher, JGM; Veerman, ECI; van Winkelhoff, AJ; Amerongen, AVH
Concentrations and output of lactoferrin and of low-M-r mucin MG2 were determined in saliva of subjects suffering from Actinobacillus actinomycetem-comitans-associated periodontal disease and healthy subjects. Periodontal patients were clinically examined and a microbiological sample was taken from
Groenink, J; Walgreen-Weterings, E; Nazmi, K; Bolscher, JGM; Veerman, ECI; van Winkelhoff, AJ; Amerongen, AVH
Concentrations and output of lactoferrin and of low-M-r mucin MG2 were determined in saliva of subjects suffering from Actinobacillus actinomycetem-comitans-associated periodontal disease and healthy subjects. Periodontal patients were clinically examined and a microbiological sample was taken from
Andresen, Lars Ole; Jacobsen, M.J.; Nielsen, J.P.
The protective efficacy of an Actinobacillus pleuropneumoniae serotype 5b capsular polysaccharide-tetanus toroid conjugate (Ap5bCP-TT) against homologous challenge of pigs was investigated. Four pigs were non-vaccinated controls (group A), 4 pigs were injected with adjuvant without antigen (group B...
Haubek, Dorte; Ennibi, O.-K.; Poulsen, Knud
A particular clone (JP2) of Actinobacillus actinomycetemcomitans with increased leukotoxin production has been isolated from individuals with early-onset periodontitis (EOP). The aim of this study was to determine the frequency of carriers of this clone and its association with EOP in Moroccan...
Groenink, J; Veerman, ECI; Zandvoort, MS; Van der Mei, HC; Busscher, HJ; Amerongen, AVN
The adhesion of Actinobacillus actinomycetemcomitans is a virulence factor in the aetiology of periodontitis and is determined by physico-chemical properties, e.g. surface charge and hydrophobicity, of the bacterial cell surface. Although oral surfaces are constantly coated with saliva, few studies
Pol, J.M.A.; Leengoed, van L.A.M.G.; Stockhofe, N.; Kok, G.; Wensvoort, G.
To study the effect of a previous porcine respiratory and reproductive syndrome-infection (PRRS) of the respiratory tract on influenza virus and Actinobacillus pleuropneumoniae (App) infections, 3-week-old specific-pathogen-free (spf) piglets were intranasally infected with PRRS virus. One week
Seitz, M; Baums, C G; Neis, C; Benga, L; Fulde, M; Rohde, M; Goethe, R; Valentin-Weigand, P
Suilysin is a pore-forming cholesterol-dependent cytolysin secreted by Streptococcus suis (S. suis), an important swine and zoonotic pathogen. The role of suilysin in S. suis host-cell interaction is still unclear. We found a higher adherence and invasion rate of an unencapsulated sly-positive strain in comparison to its isogenic sly-negative mutant. Electron microscopy revealed that formation of membrane ruffles accompanying invasion of the sly-positive strain was abolished in the sly-negative mutant. Inhibition experiments showed that the actin cytoskeleton was involved in suilysin-mediated effects. Point-mutation of the domain putatively responsible for macropore-formation resulted in abolished hemolytic and cytolysin activity, but had no effect on S. suis host cell association. Concluding, our results indicate that subcytolytic suilysin promotes S. suis association with epithelial cells.
Full Text Available The impact of age-related resistance on the regulation of population dynamics of adult Trichuris suis was investigated in an experimental pig model. Helminth-naive pigs varying in age from five weeks to four years were infected with T. suis to determine susceptibility to infection. Sows had a significantly lower establishment of adult T. suis worms compared with weaner pigs. Adult worm populations were highly overdispersed in both sows and grower pigs contrasted by a more even distribution among weaner pigs. Sows had significantly lower worm fecundities compared to weaner and grower pigs; T. suis from grower pigs, in turn, had reduced fecundity compared to worms in weaner pigs. In conclusion, we provide the first controlled experimental evidence that age-related resistance to T. suis occurs in pigs.
Nelis, Sabine; Holmes, Emily A.; Griffith, James W.; Raes, Filip
The Spontaneous Use of Imagery Scale (SUIS) is used to measure the tendency to use visual mental imagery in daily life. Its psychometric properties were evaluated in three independent samples (total N = 1297). We evaluated the internal consistency and test-retest reliability of the questionnaire. We also examined the structure of the items using exploratory and confirmatory factor analysis. Moreover, correlations with other imagery questionnaires provided evidence about convergent validity. The SUIS had acceptable reliability and convergent validity. Exploratory and confirmatory factor analysis revealed that a unidimensional structure fit the data, suggesting that the SUIS indeed measures a general use of mental imagery in daily life. Future research can further investigate and improve the psychometric properties of the SUIS. Moreover, the SUIS could be useful to determine how imagery relates to e.g. psychopathology. PMID:26290615
Full Text Available Abstract Background The sequenced genomes of the Brucella spp. have two urease operons, ure-1 and ure-2, but there is evidence that only one is responsible for encoding an active urease. The present work describes the purification and the enzymatic and phylogenomic characterization of urease from Brucella suis strain 1330. Additionally, the urease reactivity of sera from patients diagnosed with brucellosis was examined. Results Urease encoded by the ure-1 operon of Brucella suis strain 1330 was purified to homogeneity using ion exchange and hydrophobic interaction chromatographies. The urease was purified 51-fold with a recovery of 12% of the enzyme activity and 0.24% of the total protein. The enzyme had an isoelectric point of 5, and showed optimal activity at pH 7.0 and 28–35°C. The purified enzyme exhibited a Michaelis-Menten saturation kinetics with a Km of 5.60 ± 0.69 mM. Hydroxyurea and thiourea are competitive inhibitors of the enzyme with Ki of 1.04 ± 0.31 mM and 26.12 ± 2.30 mM, respectively. Acetohydroxamic acid also inhibits the enzyme in a competitive way. The molecular weight estimated for the native enzyme was between 130–135 kDa by gel filtration chromatography and 157 ± 7 kDa using 5–10% polyacrylamide gradient non-denaturing gel. Only three subunits in SDS-PAGE were identified: two small subunits of 14,000 Da and 15,500 Da, and a major subunit of 66,000 Da. The amino terminal sequence of the purified large subunit corresponded to the predicted amino acid sequence encoded by ureC1. The UreC1 subunit was recognized by sera from patients with acute and chronic brucellosis. By phylogenetic and cluster structure analyses, ureC1 was related to the ureC typically present in the Rhizobiales; in contrast, the ureC2 encoded in the ure-2 operon is more related to distant species. Conclusion We have for the first time purified and characterized an active urease from B. suis. The enzyme was characterized at the kinetic
Full Text Available The Holy See is different from the Vatican. The Vatican is a state, whereas the Holy See is the central governing institution of the Catholic Church. The position of the Holy See is in the Vatican State. The international status of the Holy See is very unique. It is a sui generis subject of international law. Although it is not a state, it enjoys international recognition. Its diplomacy consists of intern and extern aspect. The intern aspect of its diplomacy is that of church interest. The extern aspect is that of diplomacy itself. It is neutral in internationally political interests. It focuses on humanitarian and moral diplomacy.
Full Text Available Streptococcus suis (S.suis is an important emerging worldwide pig pathogen and zoonotic agent with rapid evolution of virulence and drug resistance. In this study, we wanted to investigate the effect of licochalcone A on growth and properties of Streptococcus suis. The antimicrobial activity of licochalcone A was tested by growth inhibition assay and the minimal inhibitory concentrations (MICs also were determined. The effect of licochalcone A on S.suis biofilm formation was characterized by crystal violet staining. The effect of licochalcone A on suilysin secretion was evaluated by titration of hemolytic activity. To understand the antimicrobial effect, gene expression profile of S.suis treated by licochalcone A was analyzed by DNA microarray. Our results demonstrated that licochalcone A showed antimicrobial activity on S.suis with MICs of 4 µg/ml for S.suis serotype 2 strains and 8 µg/ml for S.suis serotype 7 strains. Biofilm formation was inhibited by 30-40% in the presence of licochalcone A (3 µg/ml and suilysin secretion was also significantly inhibited in the presence of licochalcone A (1.5 µg/ml. The gene expression profile of S.suis in the presence of licochalcone A showed that 132 genes were differentially regulated, and we analyzed the regulated genes in the aspect of the bacterial cell cycle control. Among the deregulated genes, the genes responsible for the mass doubling was increased expression, but the genes responsible for DNA replication and cell division were inhibited the expression. So, we think the regulation of the cell cycle genes might provide a mechanistic understanding of licochalcone A mediated antimicrobial effect against S.suis.
Li, Lu; Xu, Zhuofei; Zhou, Yang; Sun, Lili; Liu, Ziduo; Chen, Huanchun; Zhou, Rui
Bacteria can use mammalian hormones to modulate pathogenic processes that play essential roles in disease development. Actinobacillus pleuropneumoniae is an important porcine respiratory pathogen causing great economic losses in the pig industry globally. Stress is known to contribute to the outcome of A. pleuropneumoniae infection. To test whether A. pleuropneumoniae could respond to stress hormone catecholamines, gene expression profiles after epinephrine (Epi) and norepinephrine (NE) treatment were compared with those from untreated bacteria. The microarray results showed that 158 and 105 genes were differentially expressed in the presence of Epi and NE, respectively. These genes were assigned to various functional categories including many virulence factors. Only 18 genes were regulated by both hormones. These genes included apxIA (the ApxI toxin structural gene), pgaB (involved in biofilm formation), APL_0443 (an autotransporter adhesin) and genes encoding potential hormone receptors such as tyrP2, the ygiY-ygiX (qseC-qseB) operon and narQ-narP (involved in nitrate metabolism). Further investigations demonstrated that cytotoxic activity was enhanced by Epi but repressed by NE in accordance with apxIA gene expression changes. Biofilm formation was not affected by either of the two hormones despite pgaB expression being affected. Adhesion to host cells was induced by NE but not by Epi, suggesting that the hormones affect other putative adhesins in addition to APL_0443. This study revealed that A. pleuropneumoniae gene expression, including those encoding virulence factors, was altered in response to both catecholamines. The differential regulation of A. pleuropneumoniae gene expression by the two hormones suggests that this pathogen may have multiple responsive systems for the two catecholamines. PMID:22347439
Tobias, T J; Klinkenberg, D; Bouma, A; van den Broek, J; Daemen, A J J M; Wagenaar, J A; Stegeman, J A
Actinobacillus pleuropneumoniae causes respiratory disease in pigs and despite the use of preventive measures such as vaccination and antimicrobials clinical outbreaks still occur. At weaning often many piglets are not colonised. If differences in prevalence between litters are large and if factors were known that could explain these differences, this may provide an opportunity to raise groups of A. pleuropneumoniae free piglets. To this end, a cohort study was performed on two endemically infected farrow-to-finish farms. Seventy-six of 133 sows were selected using stratified random selection by parity. Farmers complied with a strict hygiene and animal management protocol to prevent transmission between litters. Tonsil brush and serum samples taken three weeks before parturition were tested for antigen with an apxIVA qPCR and antibodies with Apx and Omp ELISAs, respectively. Three days before weaning tonsil brush samples from all piglets (n=871) were collected and tested for antigen. Whereas all sows tested positive both in serology tests as well as qPCR, 0.41 of the litters tested fully negative and 0.73 of all piglets tested negative. The proportion of positively tested piglets in positive litters ranged from 0.08-1.0 (median=0.36). A grouped logistic regression model with a beta binomial distribution of the probability for piglets to become infected was fitted to the data and associations with explanatory variables were explored. To test the possibility that alternatively the clustering was caused by onwards transmission among the piglets, a transmission model was fitted to the data incorporating sow-piglet and piglet-piglet transmission, but this model did not fit better. The results of this study showed that the number of colonised suckling piglets was highly clustered and mainly attributable to the variability of infectiousness of the dam, but no dam related risk factor for colonisation status of litter or piglets within litters could be identified. Copyright
Tremblay, Yannick D N; Lévesque, Cynthia; Segers, Ruud P A M; Jacques, Mario
Actinobacillus pleuropneumoniae is a Gram-negative bacterium and a member of the Pasteurellaceae family. This bacterium is the causative agent of porcine pleuropneumonia, which is a highly contagious respiratory disease causing important economical losses to the worldwide pig industry. It has been shown that A. pleuropneumoniae can form biofilms on abiotic surfaces (plastic and glass). Although in vitro models are extremely useful to gain information on biofilm formation, these models may not be representative of the conditions found at the mucosal surface of the host, which is the natural niche of A. pleuropneumoniae. In this paper, we describe a method to grow A. pleuropneumoniae biofilms on the SJPL cell line, which represents a biotic surface. A non-hemolytic, non-cytotoxic mutant of A. pleuropneumoniae was used in our assays and this allowed the SJPL cell monolayers to be exposed to A. pleuropneumoniae for longer periods. This resulted in the formation of biofilms on the cell monolayer after incubations of 24 and 48 h. The biofilms can be stained with fluorescent probes, such as a lectin against the polymer of N-acetyl-D-glucosamine present in the biofilm matrix, and easily observed by confocal laser scanning microscopy. This is the first protocol that describes the formation of an A. pleuropneumoniae biofilm on a biotic surface. The advantage of this protocol is that it can be used to study biofilm formation in a context of host-pathogen interactions. The protocol could also be adapted to evaluate biofilm inhibitors or the efficacy of antibiotics in the presence of biofilms.
Full Text Available Abstract Background To better understand effects of iron restriction on Actinobacillus pleuropneumoniae and to identify new potential vaccine targets, we conducted transcript profiling studies using a DNA microarray containing all 2025 ORFs of the genome of A. pleuropneumoniae serotype 5b strain L20. This is the first study involving the use of microarray technology to monitor the transcriptome of A. pleuropneumoniae grown under iron restriction. Results Upon comparing growth of this pathogen in iron-sufficient versus iron-depleted medium, 210 genes were identified as being differentially expressed. Some genes (92 were identified as being up-regulated; many have confirmed or putative roles in iron acquisition, such as the genes coding for two TonB energy-transducing proteins and the hemoglobin receptor HgbA. Transcript profiling also led to identification of some new iron acquisition systems of A. pleuropneumoniae. Genes coding for a possible Yfe system (yfeABCD, implicated in the acquisition of chelated iron, were detected, as well as genes coding for a putative enterobactin-type siderophore receptor system. ORFs for homologs of the HmbR system of Neisseria meningitidis involved in iron acquisition from hemoglobin were significantly up-regulated. Down-regulated genes included many that encode proteins containing Fe-S clusters or that use heme as a cofactor. Supplementation of the culture medium with exogenous iron re-established the expression level of these genes. Conclusion We have used transcriptional profiling to generate a list of genes showing differential expression during iron restriction. This strategy enabled us to gain a better understanding of the metabolic changes occurring in response to this stress. Many new potential iron acquisition systems were identified, and further studies will have to be conducted to establish their role during iron restriction.
Full Text Available Bacteria can use mammalian hormones to modulate pathogenic processes that play essential roles in disease development. Actinobacillus pleuropneumoniae is an important porcine respiratory pathogen causing great economic losses in the pig industry globally. Stress is known to contribute to the outcome of A. pleuropneumoniae infection. To test whether A. pleuropneumoniae could respond to stress hormone catecholamines, gene expression profiles after epinephrine (Epi and norepinephrine (NE treatment were compared with those from untreated bacteria. The microarray results showed that 158 and 105 genes were differentially expressed in the presence of Epi and NE, respectively. These genes were assigned to various functional categories including many virulence factors. Only 18 genes were regulated by both hormones. These genes included apxIA (the ApxI toxin structural gene, pgaB (involved in biofilm formation, APL_0443 (an autotransporter adhesin and genes encoding potential hormone receptors such as tyrP2, the ygiY-ygiX (qseC-qseB operon and narQ-narP (involved in nitrate metabolism. Further investigations demonstrated that cytotoxic activity was enhanced by Epi but repressed by NE in accordance with apxIA gene expression changes. Biofilm formation was not affected by either of the two hormones despite pgaB expression being affected. Adhesion to host cells was induced by NE but not by Epi, suggesting that the hormones affect other putative adhesins in addition to APL_0443. This study revealed that A. pleuropneumoniae gene expression, including those encoding virulence factors, was altered in response to both catecholamines. The differential regulation of A. pleuropneumoniae gene expression by the two hormones suggests that this pathogen may have multiple responsive systems for the two catecholamines.
Cao, Sam Linsen; Progulske-Fox, Ann; Hillman, Jeffrey D; Handfield, Martin
Actinobacillus actinomycetemcomitans is a Gram-negative capnophilic rod and the etiological agent of localized aggressive periodontitis. The genome-wide survey of A. actinomycetemcomitans using in vivo induced antigen technology (IVIAT) has previously resulted in the discovery of antigenic determinants expressed specifically in diseased patients. The present study evaluated the potential of these antigens as putative disease markers, and investigating their contribution to the pathogenesis of the microorganism. Sera from patients had a significantly greater antibody titer than sera from healthy controls against six antigens, which supports the in vivo expression of these antigens, and suggests their usefulness as disease markers. A. actinomycetemcomitans invasion of epithelium-derived HeLa cells resulted in the induction of all three genes tested, as evidenced by real-time PCR. Isogenic mutants of these three genes were constructed and the adhesion and intracellular survival of the mutants was assayed in a competition assay with the wild-type strain. A significant defect in the intracellular survival of two of these mutant strains (orf1402 and orf859) was found. This defect could not be attributed to an adhesion defect. In contrast, a mutation in vapA, a homologue of a novel putative transcriptional regulator, out-competed the wild-type strain in the same assay. The virulent phenotype was restored for a mutant strain in orf859 upon complementation. This data provided new insight into the pathogenic personality of A. actinomycetemcomitans in vivo and supported the use of HeLa cells as a valid in vitro host-pathogen interactions model for that microorganism. IVIAT is applicable to most pathogens and will undoubtedly lead to the discovery of novel therapies, antibiotics and diagnostic tools.
Roed, Casper; Engsig, Frederik Neess; Omland, Lars Haukali;
The long-term mortality in children diagnosed with Haemophilus influenzae meningitis is poorly documented.......The long-term mortality in children diagnosed with Haemophilus influenzae meningitis is poorly documented....
Nørskov-Lauritsen, Niels; Overballe, MD; Kilian, Mogens
To obtain more information on the much-debated definition of prokaryotic species, we investigated the borders of Haemophilus influenzae by comparative analysis of H. influenzae reference strains with closely related bacteria including strains assigned to Haemophilus haemolyticus, cryptic...
... taken in its entirety from the CDC Hib (Haemophilus Influenzae Type b) Vaccine Information Statement (VIS): www.cdc. ... statements/hib.pdf . CDC review information for Hib (Haemophilus Influenzae Type b) VIS: Page last reviewed: April 2, ...
Klinkenberg, D|info:eu-repo/dai/nl/248331485; Tobias, T J|info:eu-repo/dai/nl/323926789; Bouma, A|info:eu-repo/dai/nl/156999080; van Leengoed, L A M G|info:eu-repo/dai/nl/073994979; Stegeman, J A|info:eu-repo/dai/nl/137144040
Actinobacillus pleuropneumoniae is a major cause of respiratory disease in pigs. Many farms are endemically infected without apparent disease, but occasionally severe outbreaks of pleuropneumonia occur. To prevent and control these outbreaks without antibiotics, the underlying mechanisms of these
Angen, Øystein; Jessing, Stine Graakjær; Ahrens, Peter;
Based on differences in the capsular polysaccharides, 15 serotypes have until now been described for Actinobacillus pleuropneumoniae, the etiological agent of swine pleuropneumonia. Identification of the causative serotype is important both as a virulence marker and for epidemiological purposes. ...
Hedegaard, Jakob; Skovgaard, Kerstin; Mortensen, Shila;
Background: The bacterium Actinobacillus pleuropneumoniae is responsible for porcine pleuropneumonia, a widespread, highly contagious and often fatal respiratory disease of pigs. The general porcine innate immune response after A. pleuropneumoniae infection is still not clarified. The objective o...
Zhou, L.; Jones, S.C.P.; Angen, Øystein
We describe a highly sensitive and specific multiplex PCR, based on capsular loci and the species specific apxIV gene, that unequivocally differentiates serovar 3, 6, and 8 Actinobacillus pleuropneumoniae strains that are cross-reactive in conventional immunological tests.......We describe a highly sensitive and specific multiplex PCR, based on capsular loci and the species specific apxIV gene, that unequivocally differentiates serovar 3, 6, and 8 Actinobacillus pleuropneumoniae strains that are cross-reactive in conventional immunological tests....
Wittenbrink Max M
Full Text Available Abstract Background Mycoplasma suis belongs to a group of highly specialized hemotrophic bacteria that attach to the surface of host erythrocytes. Hemotrophic mycoplasmas are uncultivable and the genomes are not sequenced so far. Therefore, there is a need for the clarification of essential metabolic pathways which could be crucial barriers for the establishment of an in vitro cultivation system for these veterinary significant bacteria. Inorganic pyrophosphatases (PPase are important enzymes that catalyze the hydrolysis of inorganic pyrophosphate PPi to inorganic phosphate Pi. PPases are essential and ubiquitous metal-dependent enzymes providing a thermodynamic pull for many biosynthetic reactions. Here, we describe the identification, recombinant production and characterization of the soluble (sPPase of Mycoplasma suis. Results Screening of genomic M. suis libraries was used to identify a gene encoding the M. suis inorganic pyrophosphatase (sPPase. The M. suis sPPase consists of 164 amino acids with a molecular mass of 20 kDa. The highest identity of 63.7% was found to the M. penetrans sPPase. The typical 13 active site residues as well as the cation binding signature could be also identified in the M. suis sPPase. The activity of the M. suis enzyme was strongly dependent on Mg2+ and significantly lower in the presence of Mn2+ and Zn2+. Addition of Ca2+ and EDTA inhibited the M. suis sPPase activity. These characteristics confirmed the affiliation of the M. suis PPase to family I soluble PPases. The highest activity was determined at pH 9.0. In M. suis the sPPase builds tetramers of 80 kDa which were detected by convalescent sera from experimentally M. suis infected pigs. Conclusion The identification and characterization of the sPPase of M. suis is an additional step towards the clarification of the metabolism of hemotrophic mycoplasmas and, thus, important for the establishment of an in vitro cultivation system. As an antigenic and conserved
Full Text Available Haemophilus parasuis can be either a commensal bacterium of the porcine respiratory tract or an opportunistic pathogen causing Glässer's disease, a severe systemic disease that has led to significant economical losses in the pig industry worldwide. We determined the complete genomic sequence of H. parasuis SH0165, a highly virulent strain of serovar 5, which was isolated from a hog pen in North China. The single circular chromosome was 2,269,156 base pairs in length and contained 2,031 protein-coding genes. Together with the full spectrum of genes detected by the analysis of metabolic pathways, we confirmed that H. parasuis generates ATP via both fermentation and respiration, and possesses an intact TCA cycle for anabolism. In addition to possessing the complete pathway essential for the biosynthesis of heme, this pathogen was also found to be well-equipped with different iron acquisition systems, such as the TonB system and ABC-type transport complexes, to overcome iron limitation during infection and persistence. We identified a number of genes encoding potential virulence factors, such as type IV fimbriae and surface polysaccharides. Analysis of the genome confirmed that H. parasuis is naturally competent, as genes related to DNA uptake are present. A nine-mer DNA uptake signal sequence (ACAAGCGGT, identical to that found in Actinobacillus pleuropneumoniae and Mannheimia haemolytica, followed by similar downstream motifs, was identified in the SH0165 genome. Genomic and phylogenetic comparisons with other Pasteurellaceae species further indicated that H. parasuis was closely related to another swine pathogenic bacteria A. pleuropneumoniae. The comprehensive genetic analysis presented here provides a foundation for future research on the metabolism, natural competence and virulence of H. parasuis.
Full Text Available Streptococcus (S. suis translocates across the intestinal barrier of piglets after intraintestinal application. Based on these findings, an oro-gastrointestinal infection route has been proposed. Thus, the objective of this study was to investigate the survival of S. suis in the porcine stomach. Whereas surviving bacteria of S. suis serotypes 2 and 9 were not detectable after 60 min of incubation in stomach contents with a comparatively high gastric pH of 5 due to feeding of fine pellets, the number of Salmonella Derby bacteria increased under these conditions. Further experiments confirmed the clearance of S. suis serotypes 2 and 9 within 30 min in stomach contents with a pH of 4.7 independently of the bacterial growth phase. Finally, an oral infection experiment was conducted, feeding each of 18 piglets a diet mixed with 1010 CFU of S. suis serotype 2 or 9. Thorough bacteriological screenings of various mesenteric-intestinal lymph nodes and internal organs after different times of exposure did not lead to any detection of the orally applied challenge strains. In conclusion, the porcine stomach constitutes a very efficient barrier against oro-gastrointenstinal S. suis infections. Conditions leading to the passage of S. suis through the stomach remain to be identified.
Warneboldt, Franziska; Sander, Saara J; Beineke, Andreas; Valentin-Weigand, Peter; Kamphues, Josef; Baums, Christoph Georg
Streptococcus (S.) suis translocates across the intestinal barrier of piglets after intraintestinal application. Based on these findings, an oro-gastrointestinal infection route has been proposed. Thus, the objective of this study was to investigate the survival of S. suis in the porcine stomach. Whereas surviving bacteria of S. suis serotypes 2 and 9 were not detectable after 60 min of incubation in stomach contents with a comparatively high gastric pH of 5 due to feeding of fine pellets, the number of Salmonella Derby bacteria increased under these conditions. Further experiments confirmed the clearance of S. suis serotypes 2 and 9 within 30 min in stomach contents with a pH of 4.7 independently of the bacterial growth phase. Finally, an oral infection experiment was conducted, feeding each of 18 piglets a diet mixed with 10(10) CFU of S. suis serotype 2 or 9. Thorough bacteriological screenings of various mesenteric-intestinal lymph nodes and internal organs after different times of exposure did not lead to any detection of the orally applied challenge strains. In conclusion, the porcine stomach constitutes a very efficient barrier against oro-gastrointenstinal S. suis infections. Conditions leading to the passage of S. suis through the stomach remain to be identified.
Helicobacter (H.) suis has been associated with chronic gastritis and ulcers of the pars oesophagea in pigs, and with gastritis, peptic ulcer disease and gastric mucosa-associated lymphoid tissue lymphoma in humans. In order to obtain better insight into the genes involved in pathogenicity and in the specific adaptation to the gastric environment of H. suis, a genome analysis was performed of two H. suis strains isolated from the gastric mucosa of swine. Homologs of the vast majority of genes shown to be important for gastric colonization of the human pathogen H. pylori were detected in the H. suis genome. H. suis encodes several putative outer membrane proteins, of which two similar to the H. pylori adhesins HpaA and HorB. H. suis harbours an almost complete comB type IV secretion system and members of the type IV secretion system 3, but lacks most of the genes present in the cag pathogenicity island of H. pylori. Homologs of genes encoding the H. pylori neutrophil-activating protein and γ-glutamyl transpeptidase were identified in H. suis. H. suis also possesses several other presumptive virulence-associated genes, including homologs for mviN, the H. pylori flavodoxin gene, and a homolog of the H. pylori vacuolating cytotoxin A gene. It was concluded that although genes coding for some important virulence factors in H. pylori, such as the cytotoxin-associated protein (CagA), are not detected in the H. suis genome, homologs of other genes associated with colonization and virulence of H. pylori and other bacteria are present. PMID:21414191
Full Text Available Abstract Helicobacter (H. suis has been associated with chronic gastritis and ulcers of the pars oesophagea in pigs, and with gastritis, peptic ulcer disease and gastric mucosa-associated lymphoid tissue lymphoma in humans. In order to obtain better insight into the genes involved in pathogenicity and in the specific adaptation to the gastric environment of H. suis, a genome analysis was performed of two H. suis strains isolated from the gastric mucosa of swine. Homologs of the vast majority of genes shown to be important for gastric colonization of the human pathogen H. pylori were detected in the H. suis genome. H. suis encodes several putative outer membrane proteins, of which two similar to the H. pylori adhesins HpaA and HorB. H. suis harbours an almost complete comB type IV secretion system and members of the type IV secretion system 3, but lacks most of the genes present in the cag pathogenicity island of H. pylori. Homologs of genes encoding the H. pylori neutrophil-activating protein and γ-glutamyl transpeptidase were identified in H. suis. H. suis also possesses several other presumptive virulence-associated genes, including homologs for mviN, the H. pylori flavodoxin gene, and a homolog of the H. pylori vacuolating cytotoxin A gene. It was concluded that although genes coding for some important virulence factors in H. pylori, such as the cytotoxin-associated protein (CagA, are not detected in the H. suis genome, homologs of other genes associated with colonization and virulence of H. pylori and other bacteria are present.
Full Text Available Abstract Background Streptococcus suis serotype 2 (S. suis 2 is an important pathogen of pigs. S suis 2 infections have high mortality rates and are characterized by meningitis, septicemia and pneumonia. S. suis 2 is also an emerging zoonotic agent and can infect humans that are exposed to pigs or their by-products. To increase our knowledge of the pathogenesis of meningitis, septicemia and pneumonia in pigs caused by S. suis 2, we profiled the response of peripheral blood mononuclear cells (PBMC, brain and lung tissues to infection with S. suis 2 strain SC19 using the Affymetrix Porcine Genome Array. Results A total of 3,002 differentially expressed transcripts were identified in the three tissues, including 417 unique genes in brain, 210 in lung and 213 in PBMC. These genes showed differential expression (DE patterns on analysis by visualization and integrated discovery (DAVID. The DE genes involved in the immune response included genes related to the inflammatory response (CD163, the innate immune response (TLR2, TLR4, MYD88, TIRAP, cell adhesion (CD34, SELE, SELL, SELP, ICAM-1, ICAM-2, VCAM-1, antigen processing and presentation (MHC protein complex and angiogenesis (VEGF, together with genes encoding cytokines (interleukins. Five selected genes were validated by qRT-PCR analysis. Conclusions We studied the response to infection with S. suis 2 strain SC19 by microarray analysis. Our findings confirmed some genes identified in previous studies and discovered numerous additional genes that potentially function in S. suis 2 infections in vivo. This new information will form the foundation of future investigations into the pathogenesis of S. suis.
Full Text Available Abstract Background Porcine contagious pleuropneumonia (PCP is a highly contagious disease that is caused by Actinobacillus pleuropneumoniae (APP and characterized by severe fibrinous necrotizing hemorrhagic pleuropneumonia, which is a severe threat to the swine industry. In addition to APP RTX-toxins I (ApxI, APP RTX-toxin II (ApxII, APP RTX-toxin III (ApxIII and Outer membrane protein (OMP, there may be other useful antigens that can contribute to protection. In the development of an efficacious vaccine against APP, the immunogenicities of multicomponent recombinant subunit vaccines were evaluated. Methods Six major virulent factor genes of APP, i.e., apxI, apxII, apxIII, APP RTX-toxins IV (apxIV, omp and type 4 fimbrial structural (apfa were expressed. BALB/c mice were immunized with recombinant ApxI ( rApxI, recombinant ApxII (rApxII, recombinant ApxIII (rApxIII and recombinant OMP (rOMP (Group I; rApxI, rApxII, rApxIII, recombinant ApxIV (rApxIV, recombinant Apfa (rApfa and rOMP (Group II; APP serotype 1 (APP1 inactivated vaccine (Group III; or phosphate-buffered saline (PBS (Control group, respectively. After the first immunization, mice were subjected to two booster immunizations at 2-week intervals, followed by challenge with APP1 Shope 4074 and APP2 S1536. Results The efficacy of the multicomponent recombinant subunit vaccines was evaluated on the basis of antibody titers, survival rates, lung lesions and indirect immunofluorescence (IIF detection of APP. The antibody level of Group I was significantly higher than those of the other three groups (P P P Conclusion The result indicates that the multicomponent recombinant subunit vaccine composed of rApxI, rApxII, rApxIII and rOMP can provide effective cross-protection against homologous and heterologous APP challenge.
Zhu, Bingqing; Xiao, Di; Zhang, Huifang; Zhang, Yongchan; Gao, Yuan; Xu, Li; Lv, Jing; Wang, Yingtong; Zhang, Jianzhong; Shao, Zhujun
Nontypable Haemophilus influenzae (NTHi) and Haemophilus haemolyticus exhibit different pathogenicities, but to date, there remains no definitive and reliable strategy for differentiating these strains. In this study, we evaluated matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) as a potential method for differentiating NTHi and H. haemolyticus. The phylogenetic analysis of concatenated 16S rRNA and recombinase A (recA) gene sequences, outer membrane protein P6 gene sequencing and single-gene PCR were used as reference methods. The original reference database (ORD, provided with the Biotyper software) and new reference database (NRD, extended with Chinese strains) were compared for the evaluation of MALDI-TOF MS. Through a search of the ORD, 76.9% of the NTHi (40/52) and none of the H. haemolyticus (0/20) strains were identified at the species level. However, all NTHi and H. haemolyticus strains used for identification were accurately recognized at the species level when searching the NRD. From the dendrogram clustering of the main spectra projections, the Chinese and foreign H. influenzae reference strains were categorized into two distinct groups, and H. influenzae and H. haemolyticus were also separated into two categories. Compared to the existing methods, MALDI-TOF MS has the advantage of integrating high throughput, accuracy and speed. In conclusion, MALDI-TOF MS is an excellent method for differentiating NTHi and H. haemolyticus. This method can be recommended for use in appropriately equipped laboratories.
Xu, Lingfeng; Huang, Bo; Du, Huamao; Zhang, Xuejun C; Xu, Jianguo; Li, Xuemei; Rao, Zihe
Cholesterol-dependent cytolysins (CDC) are pore forming toxins. A prototype of the CDC family members is perfringolysin O (PFO), which directly binds to the cell membrane enriched in cholesterol, causing cell lysis. However, an exception of this general observation is intermedilysin (ILY) of Streptococcus intermedius, which requires human CD59 as a receptor in addition to cholesterol for its hemolytic activity. A possible explanation of this functional difference is the conformational variation between the C-terminal domains of the two toxins, particularly in the highly conserved undecapeptide termed tryptophan rich motif. Here, we present the crystal structure of suilysin, a CDC toxin from the infectious swine pathogen Streptococcus suis. Like PFO, suilysin does not require a host receptor for hemolytic activity; yet the crystal structure of suilysin exhibits a similar conformation in the tryptophan rich motif to ILY. This observation suggests that the current view of the structure-function relationship between CDC proteins and membrane association is far from complete.
Hsueh, Kai-Jen; Cheng, Li-Ting; Lee, Jai-Wei; Chung, Yao-Chi; Chung, Wen-Bin; Chu, Chun-Yen
Streptococcus suis (S. suis) causes arthritis, meningitis, septicemia, and sudden death in pigs and is also an zoonotic agent for humans. The present study demonstrated that immunization with recombinant Sao-L (surface antigen one-L, rSao-L) protein from a strain of S. suis serotype 2 in pigs was able to increase cross-serotype protection against S. suis serotype 1 and 2 challenge. Since weaning piglets are more susceptible to S. suis infections due to the stresses associated with weaning, prepartum immunization in sows may convey passive immunity to piglets and provide protection. Pregnant sows were immunized with a vaccine containing inactivated S. suis serotype 2 plus rSao as the antigens. Blood samples were collected from their piglets after birth for analysis of antigen-specific antibody titers and levels of various cytokines. Results demonstrated that the titers of S. suis and rSao-specific antibodies were significantly (p sows when compared to piglets from unvaccinated sows. In addition, piglets were challenged by heterologous and homologous S. suis. All piglets from unvaccinated sows developed severe symptoms of bacteremia, fever, anorexia, depression, and arthritis. On the other hand, piglets from vaccinated sows had significantly (p sows with the vaccine containing inactivated S. suis bacterin plus rSao as the antigens is able to enhance passive immunity against heterologous and homologous S. suis challenge in their piglets.
Angen, Øystein; Ahrens, Peter; Jessing, Stine Graakjær
A PCR assay for simultaneous species identification and separation of Actinobacillus pleuropneumoniae serovars 1, 7 and 12 was developed. Primers specific for genes involved in biosynthesis of the capsular polysaccharides (cps genes) of serovars 1, 7,and 12 were combined with a species-specific PCR...... test based on the omlA gene. The PCR test was evaluated with the serovar reference strains of A. pleuropneumoniae as well as 183 Danish field isolates. For all typable strains, a complete correspondence was found between results obtained with the multiplex PCR test and results from the traditional...... representing 25 different species within the family Pasteurellaceae including 45 field strains of the phylogenetically affiliated species Actinobacillus lignieresii. All these isolates tested negative for the cps genes by the multiplex PCR test except for 6 isolates of A. lignieresii. Five of these isolates...
Kokotovic, Branko; Angen, Øystein
Amplified fragment length polymorphism (AFLP) was evaluated as a method for genotypic characterization and subtyping within the bacterial species Actinobacillus pleuropneumoniae. A total of 155 isolates of A. pleuropneumoniae, representing the serotypic variation described to occur within...... this species, were analyzed. In order to elucidate the species boundaries, six strains of the phylogenetically closely related species Actinobacillus lignieresii were also included. Furthermore, the ability of AFLP to subtype was studied using 42 isolates of serovar 2 and the performance compared...... to that obtained by pulsed-field gel electrophoresis (PFGE). AFLP analysis provided a clear separation of A. lignieresii and A. pleuropneumoniae and divided the isolates of A. pleuropneumoniae into 20 clusters. Most of the serovars of A. pleuropneumoniae were represented by single and quite homogeneous clusters...
Fontanals, D; Bou, R; Pons, I; Sanfeliu, I; Domínguez, A; Pineda, V; Renau, J; Muñoz, C; Latorre, C; Sanchez, F
This study was designed to determine the prevalence of healthy Haemophilus influenzae carriers in a random sample of the preschool population in Catalonia. Oropharyngeal swabs were collected and cultured on chocolate agar supplemented with 260 microg/ml of bacitracin. Four hundred two of the 734 (54.8%) children studied were detected as Haemophilus influenzae carriers: 7 (0.9%) carried serotype b, 14 (1.9%) serotype e, 6 (0.8%) serotype f, and 375 (51%) carried nontypable strains. The results show that, although the prevalence of Haemophilus influenzae carriers is similar to figures reported from other countries, the prevalence of Haemophillus influenzae serotype b carriers is lower and corresponds with the low incidence of invasive disease observed in the Catalan community.
Risco, David; Fernández-Llario, Pedro; Cuesta, Jesús M; García-Jiménez, Waldo L; Gonçalves, Pilar; Martínez, Remigio; García, Alfredo; Rosales, Rubén; Gómez, Luis; de Mendoza, Javier Hermoso
Streptococcus suis is a recognized pathogen that may cause important diseases in pigs and humans. This microorganism has been repeatedly isolated from wild boar (Sus scrofa). However, its health implications for this wild species are still unknown. This article reports a detailed description of a fatal case of septicemia by S. suis affecting a young wild boar. The affected animal, about 15 days old, was found near death and exhibiting neurologic signs at a wild boar estate in southwestern Spain. Postmortem examination showed generalized congestion, brain hemorrhages and lobular pneumonia. Histopathological evaluation demonstrated the presence of meningitis and encephalitis with marked congestion and suppurative bronchopneumonia. Streptococcus suis serotype 2 isolates exhibiting important virulence factors (extracellular factor, muramidase-released protein, and suylisin) were isolated from the affected animal. This study confirms the presence of potentially virulent and zoonotic strains of S. suis in wild boar from Spain.
Silva, L.M.G.; Baums, C.G.; Rehm, T.; Wisselink, H.J.; Goethe, R.; Valentin-Weigand, P.
Definition of virulent Streptococcus suis strains is controversial. One successful approach for identification of virulent European strains is differentiation of capsular serotypes (or the corresponding cps types) and subsequent detection of virulence-associated factors, namely the extracellular fac
Franco F. Calderaro
Full Text Available Abstract: Streptococcus suis is one of most important pathogens in the swine industry worldwide. Despite its importance, studies of S. suis characterization in South America are still rare. This study evaluates S. suis isolates from distinct Brazilian states, from 1999 to 2004, and its molecular and serological characterization. A total of 174 isolates were studied. S. suis identification was confirmed by PCR and isolates were further serotyped and genotyped by SE-AFLP and amplification of virulence markers. Serotype 1, 2, 3, 4, 7, 18, 22 and 32 were identified among the studied isolates, and only 4% were characterized as non-typeable. The mrp+/epf+/sly+ genotype was the most frequent. The SE-AFLP analysis resulted in 29 patterns distributed in three main clusters with over 65% of genetic similarity. Isolates presented a slight tendency to cluster according to serotype and origin; however, no further correlation with virulence genotypes was observed.
Ian T. Paulsen; Rekha Seshadri; Karen E. Nelson; Jonathan A. Eisen; John F. Heidelberg; Timothy D. Read; Robert J. Dodson; Lowell Umayam; Lauren M. Brinkac; Maureen J. Beanan; Sean C. Daugherty; Robert T. Deboy; A. Scott Durkin; James F. Kolonay; Ramana Madupu; William C. Nelson; Bola Ayodeji; Margaret Kraul; Jyoti Shetty; Joel Malek; Susan E. van Aken; Steven Riedmuller; Herve Tettelin; Steven R. Gill; Owen White; Steven L. Salzberg; David L. Hoover; Luther E. Lindler; Shirley M. Halling; Stephen M. Boyle; Claire M. Fraser
.... Extensive gene synteny between B. suis chromosome 1 and the genome of the plant symbiont Mesorhizobium loti emphasizes the similarity between this animal pathogen and plant pathogens and symbionts...
Diarra, M. S.; Dolence, J A; Dolence, E K; Darwish, I; Miller, M.J.; Malouin, F; Jacques, M.
Siderophores bind ferric ions and are involved in receptor-specific iron transport into bacteria. Six types of siderophores were tested against strains representing the 12 different serotypes of Actinobacillus pleuropneumoniae. Ferrichrome and bis-catechol-based siderophores showed strong growth-promoting activities for A. pleuropneumoniae in a disk diffusion assay. Most strains of A. pleuropneumoniae tested were able to use ferrichrome (21 of 22 or 95%), ferrichrome A (20 of 22 or 90%), and ...
Shea, Robin J.; Mulks, Martha H.
Actinobacillus pleuropneumoniae is the causative agent of porcine pleuropneumonia, a disease characterized by pulmonary necrosis and hemorrhage caused in part by neutrophil degranulation. In an effort to understand the pathogenesis of this disease, we have developed an in vivo expression technology (IVET) system to identify genes that are specifically up-regulated during infection. One of the genes that we have identified as being induced in vivo is ohr, encoding organic hydroperoxide reducta...
Despite its typically gram-negative cell envelope ultrastructure, Pasteurella multocida is susceptible to the hydrophobic antibiotic novobiocin and is unable to initiate growth on MacConkey agar, a parameter often used to effect is differentiation from other members of the family Pasteurellaceae such as Actinobacillus lignieresii. However, growth on basal medium supplemented with individual selective factors and an agar diffusion assay revealed the bile salts contained in MacConkey agar to be...
Chung, W. B.; Bäckström, L R; Collins, M T
This study was designed to develop and characterize a swine pneumonic pasteurellosis model by concurrent introduction of Pasteurella multocida type A and Actinobacillus pleuropneumoniae crude cytotoxin. After a series of preliminary experiments, a combination of 4 x 10(9) P. multocida and 4,000 toxic units of A. pleuropneumoniae crude cytotoxin was determined to produce optimal results. A total of 48 pigs were divided into four groups of 12 pigs each. The control group received buffered salin...
Chung, W. B.; Bäckström, L; McDonald, J.; Collins, M T
The effect of Actinobacillus pleuropneumoniae culture supernatant on swine pulmonary alveolar macrophage (PAM) functions was studied. The A. pleuropneumoniae culture supernatant was toxic to PAMs when tested by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) and lactate dehydrogenase (LDH) release assays. Biological activity of the supernatant was ascribed to cytotoxins. Both the LDH and MTT assays were used for measurement of crude A. pleuropneumoniae cytotoxin concentrati...
Martin Sager; Benten, W. Peter M.; Eva Engelhardt; Christina Gougoula; Laurentiu Benga
[Pasteurella] pneumotropica biotypes Jawetz and Heyl and [Actinobacillus] muris are the most prevalent Pasteurellaceae species isolated from laboratory mouse. However, mechanisms contributing to their high prevalence such as the ability to form biofilms have not been studied yet. In the present investigation we analyze if these bacterial species can produce biofilms in vitro and investigate whether proteins, extracellular DNA and polysaccharides are involved in the biofilm formation and struc...
Actinobacillus actinomycetemcomitans is present in elevated proportions and numbers in dental bacterial biofilms of patients with localized aggressive periodontitis. This variant of periodontal disease, occurring in adolescents and young adults, is characterized by rapid and severe destruction of the connective tissues and bone supporting the teeth, eventually culminating in tooth loss. The cytolethal distending toxin (Cdt) is a newly discovered bacterial protein toxin, uniquely present in A....
Seitz, Maren; Beineke, Andreas; Singpiel, Alena; Willenborg, Jörg; Dutow, Pavel; Goethe, Ralph; Valentin-Weigand, Peter; Klos, Andreas; Baums, Christoph G
Virulent Streptococcus suis serotype 2 strains are invasive extracellular bacteria causing septicemia and meningitis in piglets and humans. One objective of this study was to elucidate the function of complement in innate immune defense against S. suis. Experimental infection of wild-type (WT) and C3(-/-) mice demonstrated for the first time that the complement system protects naive mice against invasive mucosal S. suis infection. S. suis WT but not an unencapsulated mutant caused mortality associated with meningitis and other pathologies in C3(-/-) mice. The capsule contributed also substantially to colonization of the upper respiratory tract. Experimental infection of C3(-/-) mice with a suilysin mutant indicated that suilysin expression facilitated an early disease onset and the pathogenesis of meningitis. Flow cytometric analysis revealed C3 antigen deposition on the surface of ca. 40% of S. suis WT bacteria after opsonization with naive WT mouse serum, although to a significantly lower intensity than on the unencapsulated mutant. Ex vivo multiplication in murine WT and C3(-/-) blood depended on capsule but not suilysin expression. Interestingly, S. suis invasion of inner organs was also detectable in C5aR(-/-) mice, suggesting that chemotaxis and activation of immune cells via the anaphylatoxin receptor C5aR is, in addition to opsonization, a further important function of the complement system in defense against mucosal S. suis infection. In conclusion, we unequivocally demonstrate here the importance of complement against mucosal S. suis serotype 2 infection and that the capsule of this pathogen is also involved in escape from complement-independent immunity.
Lebel, Geneviève; Piché, Fanny; Frenette, Michel; Gottschalk, Marcelo; Grenier, Daniel
Streptococcus suis serotype 2 is known to cause severe infections in pigs, including meningitis, endocarditis and pneumonia. Furthermore, this bacterium is considered an emerging zoonotic agent. Recently, increased antibiotic resistance in S. suis has been reported worldwide. The objective of this study was to evaluate the potential of nisin, a bacteriocin of the lantibiotic class, as an antibacterial agent against the pathogen S. suis serotype 2. In addition, the synergistic activity of nisin in combination with conventional antibiotics was assessed. Using a plate assay, the nisin-producing strain Lactococcus lactis ATCC 11454 proved to be capable of inhibiting the growth of S. suis (n=18) belonging to either sequence type (ST)1, ST25, or ST28. In a microdilution broth assay, the minimum inhibitory concentration (MIC) of purified nisin ranged between 1.25 and 5 μg/mL while the minimum bactericidal concentration (MBC) was between 5 and 10 μg/mL toward S. suis. The use of a capsule-deficient mutant of S. suis indicated that the presence of this polysaccharidic structure has no marked impact on susceptibility to nisin. Following treatment of S. suis with nisin, transmission electron microscopy observations revealed lysis of bacteria resulting from breakdown of the cell membrane. A time-killing curve showed a rapid bactericidal activity of nisin. Lastly, synergistic effects of nisin were observed in combination with several antibiotics, including penicillin, amoxicillin, tetracycline, streptomycin and ceftiofur. This study brought clear evidence supporting the potential of nisin for the prevention and treatment of S. suis infections in pigs.
Full Text Available Streptococcus suis is a Gram-positive bacterium, which causes sepsis and meningitis in pigs and humans. This review examines the role of known S. suis virulence factors in adhesion and S. suis carbohydrate-based adhesion mechanisms, as well as the inhibition of S. suis adhesion by anti-adhesion compounds in in vitro assays. Carbohydrate-binding specificities of S. suis have been identified, and these studies have shown that many strains recognize Galα1-4Gal-containing oligosaccharides present in host glycolipids. In the era of increasing antibiotic resistance, new means to treat infections are needed. Since microbial adhesion to carbohydrates is important to establish disease, compounds blocking adhesion could be an alternative to antibiotics. The use of oligosaccharides as drugs is generally hampered by their relatively low affinity (micromolar to compete with multivalent binding to host receptors. However, screening of a library of chemically modified Galα1-4Gal derivatives has identified compounds that inhibit S. suis adhesion in nanomolar range. Also, design of multivalent Galα1-4Gal-containing dendrimers has resulted in a significant increase of the inhibitory potency of the disaccharide. The S. suis adhesin binding to Galα1-4Gal-oligosaccharides, Streptococcal adhesin P (SadP, was recently identified. It has a Galα1-4Gal-binding N-terminal domain and a C-terminal LPNTG-motif for cell wall anchoring. The carbohydrate-binding domain has no homology to E. coli P fimbrial adhesin, which suggests that these Gram-positive and Gram-negative bacterial adhesins recognizing the same receptor have evolved by convergent evolution. SadP adhesin may represent a promising target for the design of anti-adhesion ligands for the prevention and treatment of S. suis infections.
Andresen, Lars Ole; Tegtmeier, Conny
The safety and protective efficacy of a horse antiserum raised against inactivated whole cell preparations of Streptococcus suis serotype 2 was investigated in pigs by experimental challenge. The antiserum was evaluated in two similar experiments each comprising 12 4-week-old pigs treated with 6 ...... indicate that passive immunization of pigs may be a way to reduce or control S. suis serotype 2 infections in pigs....
Full Text Available Introduction: The bacteria that cause the occurrence of pathogens of periodontal disease are gram negative anaerobes. These bacteria include Pophyromonas Gingivalis and Actinobacillus Actinomycetemcomitans. Mangosteen skin extract is known to have anti-inflammatory, anti microbial, and anti oxidant properties. The extract of the mangosteen peel is altered in gel preparation in order to streamline its clinical application in periodontal disease. The purpose of this study was to examine the antibacterial power of the ginger mangosteen tree extract gel against Pophyromonas gingivalis and Actinobacillus Actinomycetemcomitans (Aggregatibacter Actinomycetemcomitans. Methods: This research was conducted by experimental laboratory. Mangosteen fruit extract gel with concentration of 100%, 50%, 25%, 12,5%, 6,25%, 3,125% and 0,78% were tested against Pophyromonas Gingivalis and Aggregatibacter Actinomycetemcomitans with agar diffusion method. Results and Discussion: The results of this study indicate that for Actinobacilus Aggregatibacter bacteria minimal inhibitory concentration at a concentration of 6.25% with a diameter of 13,5mm inhibition. Minimal bactericidal concentration at 12,5% concentration with 14,7mm inhibitory diameter. In the test of Pophyromonas Gingivalis bacteria, minimal inhibitory concentrations were obtained at a concentration of 1.56% and a minimum bactericidal concentration was obtained at a concentration of 3.125%. Conclusion: The conclusion that mangosteen peel skin gel extract can inhibit bacterial growth and is bactericidal against Pophyromonas Gingivalis and Actinobacillus Actinomycetemcomitans (Aggregatibacter Actinomycetecomitans.
Ward, Alton C S; Weiser, Glen C; Anderson, Bruce C; Cummings, Patrick J; Arnold, Karen F; Corbeil, Lynette B
Respiratory disease and poor lamb recruitment have been identified as limiting factors for bighorn-sheep populations. Haemophilus somnus (recently reclassified as Histophilus somni) is associated with respiratory disease in American bison, domestic sheep, and cattle. It is also harbored in their reproductive tracts and has been associated with reproductive failure in domestic sheep and cattle. Therefore, reproductive tract and lung samples from bighorn sheep were evaluated for the presence of this organism. Organisms identified as H. somnus were isolated from 6 of 62 vaginal but none of 12 preputial swab samples. Antigen specific to H. somnus was detected by immunohistochemical study in 4 of 12 formalin-fixed lung tissue samples of bighorn sheep that died with evidence of pneumonia. Notably, H. somnus was found in alveolar debris in areas of inflammation. The 6 vaginal isolates and 2 H. somnus isolates previously cultured from pneumonic lungs of bighorn sheep were compared with 3 representative isolates from domestic sheep and 2 from cattle. The profiles of major outer membrane proteins and antigens for all of the isolates were predominantly similar, although differences that may be associated with the host-parasite relationship and virulence were detected. The DNA restriction fragment length profiles of the bighorn-sheep isolates had similarities not shared with the other isolates, suggesting distinct phylogenetic lines. All of the isolates had similar antimicrobial profiles, but the isolates from the bighorn sheep produced less pigment than those from the domestic livestock, and growth of the former was not enhanced by CO2. Wildlife biologists and diagnosticians should be aware of the potential of these organisms to cause disease in bighorn sheep and of growth characteristics that may hinder laboratory detection.
Pérez-Sancho, Marta; Vela, Ana Isabel; García-Seco, Teresa; Gottschalk, Marcelo; Domínguez, Lucas; Fernández-Garayzábal, José Francisco
The accuracy of matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) for identifying Streptococcus suis isolates obtained from pigs, wild animals, and humans was evaluated using a PCR-based identification assay as the gold standard. In addition, MALDI-TOF MS was compared with the commercial multi-tests Rapid ID 32 STREP system. From the 129 S. suis isolates included in the study and identified by the molecular method, only 31 isolates (24.03%) had score values ≥2.300 and 79 isolates (61.24%) gave score values between 2.299 and 2.000. After updating the currently available S. suis MALDI Biotyper database with the spectra of three additional clinical isolates of serotypes 2, 7, and 9, most isolates had statistically significant higher score values (mean score: 2.65) than those obtained using the original database (mean score: 2.182). Considering the results of the present study, we suggest using a less restrictive threshold score of ≥2.000 for reliable species identification of S. suis. According to this cut-off value, a total of 125 S. suis isolates (96.9%) were correctly identified using the updated database. These data indicate an excellent performance of MALDI-TOF MS for the identification of S. suis. PMID:26347858
Full Text Available Muramidase-released protein (MRP is as an important virulence marker of Streptococcus suis (S. suis serotype 2. Our previous works have shown that MRP can bind human fibrinogen (hFg; however, the function of this interaction in S.suis meningitis is not known. In this study, we found that the deletion of mrp significantly impairs the hFg-mediated adherence and traversal ability of S. suis across human cerebral microvascular endothelial cells (hCMEC/D3. Measurement of the permeability to Lucifer yellow in vitro and Evans blue extravasation in vivo show that the MRP-hFg interaction significantly increases the permeability of the blood-brain barrier (BBB. In the mouse meningitis model, wild type S. suis caused higher bacterial loads in the brain and more severe histopathological signs of meningitis than the mrp mutant at day 3 post-infection. Western blot analysis and immunofluorescence observations reveal that the MRP-hFg interaction can destroy the cell adherens junction protein p120-catenin of hCMEC/D3. These results indicate that the MRP-hFg interaction is important in the development of S. suis meningitis.
Søndergaard, Annette; Lund, Marianne; Nørskov-Lauritsen, Niels
Only two beta-lactamases, TEM-1 and ROB-1, have been observed in Haemophilus influenzae, while four different TEM but no ROB enzymes have been found in Haemophilus parainfluenzae. In order to investigate the mechanisms behind the dissemination of small beta-lactamase-encoding plasmids in H. influenzae and H. parainfluenzae, we assessed the fitness cost of three TEM-1- (pPN223, pA1209, pA1606), one TEM-15- (pSF3) and one ROB-1-bearing (pB1000) plasmid when expressed in either bacterial species. All plasmids were stable in H. influenzae and H. parainfluenzae except pB1000, which showed on average (sample mean) 76% curing in H. parainfluenzae after 5 days of subculture. Competition assays between isogenic strains with and without plasmid showed no competitive disadvantage of pPN223 and pA1606 in H. influenzae, or of pA1209 in H. parainfluenzae. In contrast, pSF3 and pB1000 were associated with significant competitive disadvantages in both species. Some of the competitive disadvantages may be related to differences in plasmid copy number and mRNA expression of the beta-lactamase genes, as revealed by quantitative PCR analysis. In conclusion, plasmids encoding TEM beta-lactamases isolated from H. influenzae and H. parainfluenzae can be stably transferred between species. The fast curing of pB1000 in H. parainfluenzae observed in this study correlates to the fact that ROB-1 has never been reported for this species. TEM-1-encoding plasmids are associated with the lowest level of fitness cost, but different TEM-1 plasmids confer different levels of fitness cost on the two hosts.
Mount, Kristy L. B.; Townsend, Carisa A.; Bauer, Margaret E.
We examined the susceptibility of Haemophilus ducreyi to antimicrobial peptides likely to be encountered in vivo during human infection. H. ducreyi was significantly more resistant than Escherichia coli to the bactericidal effects of all peptides tested. Class I and II H. ducreyi strains exhibited similar levels of resistance to antimicrobial peptides.
Peel, Trisha N; Bhatti, Deepak; De Boer, Jim C; Stratov, Ivan; Spelman, Denis W
Haemophilus ducreyi is a well recognised causative agent of genital ulcers and chancroid. We report two unusual cases of non-sexually transmitted H. ducreyi infection leading to chronic lower limb ulcers. Both patients were Australian expatriates visiting Australia from the Pacific Islands--one from Papua New Guinea and the other from Vanuatu.
Mount, Kristy L B; Townsend, Carisa A; Bauer, Margaret E
We examined the susceptibility of Haemophilus ducreyi to antimicrobial peptides likely to be encountered in vivo during human infection. H. ducreyi was significantly more resistant than Escherichia coli to the bactericidal effects of all peptides tested. Class I and II H. ducreyi strains exhibited similar levels of resistance to antimicrobial peptides.
Ussher, James E; Wilson, Elizabeth; Campanella, Silvana; Taylor, Susan L; Roberts, Sally A
Chancroid is a sexually transmitted infection associated with genital ulceration and lymphadenopathy caused by Haemophilus ducreyi. Localized skin infections, in the absence of genital lesions, have not been previously reported. We report 3 cases of lower limb ulceration in children caused by H. ducreyi and postulate that H. ducreyi may be a previously unrecognized cause of chronic skin ulceration.
Marks, Michael; Chi, Kai-Hua; Vahi, Ventis; Pillay, Allan; Sokana, Oliver; Pavluck, Alex; Mabey, David C; Chen, Cheng Y; Solomon, Anthony W
During a survey of yaws prevalence in the Solomon Islands, we collected samples from skin ulcers of 41 children. Using PCR, we identified Haemophilus ducreyi infection in 13 (32%) children. PCR-positive and PCR-negative ulcers were phenotypically indistinguishable. Emergence of H. ducreyi as a cause of nongenital ulcers may affect the World Health Organization's yaws eradication program.
Marks, M; Chi, KH; Vahi, V; Pillay, A.; Sokana, O; Pavluck, A; Mabey, DC; Chen, CY; Solomon, AW
During a survey of yaws prevalence in the Solomon Islands, we collected samples from skin ulcers of 41 children. Using PCR, we identified Haemophilus ducreyi infection in 13 (32%) children. PCR-positive and PCR-negative ulcers were phenotypically indistinguishable. Emergence of H. ducreyi as a cause of nongenital ulcers may affect the World Health Organization's yaws eradication program.
Nielsen, Jette Dettmann; Lind, Jens Wentzel; Bruun, Britta;
Two cases of invasive Haemophilus influenzae type f infection are presented: a three-week-old boy with meningitis and a 62-year-old woman with arthritis and bacteremia. Since 1993 vaccination against H. influenzae type b (Hib) has been offered to Danish children. The result has been a remarkable...
Vilmar, A.C.; Gjorup, I.; David, Kim Peter
Haemophilus influenzae b (Hib) can be the cause of serious infections, and is mainly observed affecting children and immuno-compromised patients. We report a case of a healthy 49-year old male with a severe Hib infection complicated by septicaemia, meningitis and anuria. The risk of invasive Hib...
Ronit, Andreas; Berg, Ronan M G; Bruunsgaard, Helle;
Non-serotype b strains of Haemophilus influenzae are extremely rare causes of acute bacterial meningitis in immunocompetent individuals. We report a case of acute bacterial meningitis in a 14-year-old boy, who was previously healthy and had been immunised against H influenzae serotype b (Hib...
Nielsen, J.D.; Lind, J.W.; Bruun, B.
Two cases of invasive Haemophilus influenzae type f infection are presented: a three-week-old boy with meningitis and a 62-year-old woman with arthritis and bacteremia. Since 1993 vaccination against H. influenzae type b (Hib) has been offered to Danish children. The result has been a remarkable...
Kuo, Shu-Chen; Chen, Pei-Chen; Shiau, Yih-Ru; Wang, Hui-Ying; Lai, Jui-Fen; Huang, Wen; Lauderdale, Tsai-Ling Yang
Levofloxacin resistance in Haemophilus influenzae has increased significantly in Taiwan, from 2.0% in 2004 to 24.3% in 2010 (p<0.001). Clinical and molecular investigations of 182 levofloxacin-resistant isolates revealed that the increase was mainly the result of the spread of several clones in the elderly population in different regions.
Nielsen, Jette Dettmann; Lind, Jens; Bruun, Brita
Two cases of invasive Haemophilus influenzae type f infection are presented: a three-week-old boy with meningitis and a 62-year-old woman with arthritis and bacteremia. Since 1993 vaccination against H. influenzae type b (Hib) has been offered to Danish children. The result has been a remarkable...
Nielsen, J.D.; Lind, J.W.; Bruun, B.
McCarthy, D.; Griffin, K.; Setlow, J.K.
A ligase gene from Haemophilus influenzae was cloned into the shuttle vector pDM2. Although the plasmid did not affect X-ray sensitivity, it caused an increase in UV sensitivity of the wild-type but not excision-defective H. influenzae and a decrease in UV sensitivity of the rec-1 mutant. 14 references, 2 figures.
Strains of Haemophilus influenzae that carry a defective prophage are more sensitive to heat than is a strain that does not, even in the presence of a rec-I mutation, which normally renders prophage noninducible. The prophage of HPlcl, a nondefective phage, does not affect the heat sensitivity.
McCarthy, D.; Clayton, N.L.; Setlow, J.K.
A new plasmid cloning vehicle (pDM2) was used to introduce a library of Haemophilus influenzae chromosomal fragments into H. influenzae. Transformants of the higly recombination-defective rec-1 mutant were more likely to contain exclusively recombinant plasmids after exposure to ligated DNA mixtures than was the wild type. pDM2 could replicate in Escherichia coli K-12.
Haemophilus parasuis is a small, pleomorphic Gram-negative bacterium that colonizes the upper respiratory tract of swine. Numerous strains of this organism are capable of causing systemic disease, resulting in high morbidity and mortality in the host. H. parasuis isolates display a wide range of vir...
Haemophilus parasuis is the causative agent of Glässers disease in swine, which is characterized by systemic invasion of the bacteria to serosal surfaces, resulting in inflammation and induction of pleuritis, peritonitis, and arthritis. In addition, certain strains of H. parasuis cause pneumonia wh...
ABSTRACT Haemophilus influenzae is an important human pathogen that primarily infects small children. In recent years, H. influenzae serotype a has emerged as a significant cause of invasive disease among indigenous populations. Here, we present the first complete whole-genome sequence of H. influenzae serotype a. PMID:28104664
Challacombe, Jean F; Duncan, A J; Brettin, Thomas S; Bruce, David; Chertkov, Olga; Detter, J Chris; Han, Cliff S; Misra, Monica; Richardson, Paul; Tapia, Roxanne; Thayer, Nina; Xie, Gary; Inzana, Thomas J
Haemophilus somnus can be either a commensal of bovine mucosal surfaces or an opportunistic pathogen. Pathogenic strains of H. somnus are a significant cause of systemic disease in cattle. We report the genome sequence of H. somnus 129Pt, a nonpathogenic commensal preputial isolate, and the results of a genome-wide comparative analysis of H. somnus 129Pt, Haemophilus influenzae Rd, and Haemophilus ducreyi 35000HP. We found unique genes in H. somnus 129Pt involved in lipooligosaccharide biosynthesis, carbohydrate uptake and metabolism, cation transport, amino acid metabolism, ubiquinone and menaquinone biosynthesis, cell surface adhesion, biosynthesis of cofactors, energy metabolism, and electron transport. There were also many genes in common among the three organisms. Our comparative analyses of H. somnus 129Pt, H. influenzae Rd, and H. ducreyi 35000HP revealed similarities and differences in the numbers and compositions of genes involved in metabolism, host colonization, and persistence. These results lay a foundation for research on the host specificities and niche preferences of these organisms. Future comparisons between H. somnus 129Pt and virulent strains will aid in the development of protective strategies and vaccines to protect cattle against H. somnus disease.
Full Text Available Questo lavoro si propone di analizzare le scelte linguistiche dei soggetti politici che utilizzano Facebook e Twitter per rivolgersi al sempre più frammentato panorama dei potenziali elettori. In particolare, analizza le tendenze linguistiche comuni che questi social network hanno fatto emergere nel rapporto tra politica, web e lettori. Cominciando dall’analisi della presenza di parlamentari e senatori su Facebook e Twitter, si cerca di riassumere le principali caratteristiche delle due piattaforme, per giungere ad una classificazione dei testi prodotti attraverso di esse; si analizza la scrittura di post e tweet, sottolineando la presenza di espedienti tipici del mezzo e valutando il loro effetto sui lettori, e si studiano le scelte sintattiche e morfosintattiche in relazione alla struttura e alle possibilità dei due social network. In ultima analisi si osservano le scelte lessicali dei soggetti politici, studiandone i campi semantici e la quantità di tecnicismi. Infine, si cerca di compiere una valutazione delle due differenti tipologie di trasmesso scritto rinvenute nei campioni, osservando come ognuna di esse abbia uno scopo ben preciso nell’economia della comunicazione politica sui social network. Political communication policy in social networks: a language analysis Daniele Spoladore This paper aims to analyze the linguistic choices of politicians who use Facebook and Twitter to address the increasingly fragmented landscape of potential voters. In particular, it analyzes the common language trends that these social networks have revealed in the relationship between politics, the web and readers. Starting from the analysis of the presence of MPs and senators on Facebook and Twitter, we try to summarize the key features of the two platforms, in order to arrive at a classification of the texts produced using them. We analyzed posts and tweets, emphasizing the typical characteristics of these means and evaluating their effect on
Jubier-Maurin, Véronique; Rodrigue, Agnès; Ouahrani-Bettache, Safia; Layssac, Marion; Mandrand-Berthelot, Marie-Andrée; Köhler, Stephan; Liautard, Jean-Pierre
Analysis of a Brucella suis 1330 gene fused to a gfp reporter, and identified as being induced in J774 murine macrophage-like cells, allowed the isolation of a gene homologous to nikA, the first gene of the Escherichia coli operon encoding the specific transport system for nickel. DNA sequence analysis of the corresponding B. suis nik locus showed that it was highly similar to that of E. coli except for localization of the nikR regulatory gene, which lies upstream from the structural nikABCDE genes and in the opposite orientation. Protein sequence comparisons suggested that the deduced nikABCDE gene products belong to a periplasmic binding protein-dependent transport system. The nikA promoter-gfp fusion was activated in vitro by low oxygen tension and metal ion deficiency and was repressed by NiCl2 excess. Insertional inactivation of nikA strongly reduced the activity of the nickel metalloenzyme urease, which was restored by addition of a nickel excess. Moreover, the nikA mutant of B. suis was functionally complemented with the E. coli nik gene cluster, leading to the recovery of urease activity. Reciprocally, an E. coli strain harboring a deleted nik operon recovered hydrogenase activity by heterologous complementation with the B. suis nik locus. Taking into account these results, we propose that the nik locus of B. suis encodes a nickel transport system. The results further suggest that nickel could enter B. suis via other transport systems. Intracellular growth rates of the B. suis wild-type and nikA mutant strains in human monocytes were similar, indicating that nikA was not essential for this step of infection. We discuss a possible role of nickel transport in maintaining enzymatic activities which could be crucial for survival of the bacteria under the environmental conditions encountered within the host. PMID:11133934
Liang, Jungang; De Bruyne, Ellen; Ducatelle, Richard; Smet, Annemieke; Haesebrouck, Freddy; Flahou, Bram
Helicobacter (H.) suis causes gastritis and decreased weight gain in pigs. It is also the most prevalent non-Helicobacter pylori Helicobacter species in humans with gastric disease. H. suis is extremely fastidious, and so far, biphasic culture conditions were essential for isolation and culture, making it impossible to obtain single colonies. Hence, cultures obtained from an individual animal may contain multiple H. suis strains, which is undesirable for experiments aiming for instance at investigating H. suis strain differences. Pure cultures of H. suis were established by growing bacteria as colonies on 1% brucella agar plates, followed by purification and enrichment by biphasic subculture. Characteristics of these single colony-derived strains were compared with those of their parent strains using multilocus sequence typing (MLST) and by studying bacterium-host interactions using a gastric epithelial cell line and Mongolian gerbil model. The purification/enrichment procedure required a nonstop culture of several weeks. For 4 of 17 H. suis strains, MLST revealed differences between parental and single colony-derived strains. For three of four single colony-derived strains tested, the cell death-inducing capacity was higher than for the parental strain. One single colony-derived strain lost its capacity to colonize Mongolian gerbils. For the four other strains tested, colonization capacity and histopathologic changes were similar to what has been described when using strains with only a history of limited biphasic culture. A method was developed to obtain single colony-derived H. suis strains, but this procedure may affect the bacterial genotype and phenotype. © 2015 John Wiley & Sons Ltd.
Full Text Available Abstract Background Streptococcus suis is a zoonotic pathogen that causes infections in young piglets. S. suis is a heterogeneous species. Thirty-three different capsular serotypes have been described, that differ in virulence between as well as within serotypes. Results In this study, the correlation between gene content, serotype, phenotype and virulence among 55 S. suis strains was studied using Comparative Genome Hybridization (CGH. Clustering of CGH data divided S. suis isolates into two clusters, A and B. Cluster A isolates could be discriminated from cluster B isolates based on the protein expression of extracellular factor (EF. Cluster A contained serotype 1 and 2 isolates that were correlated with virulence. Cluster B mainly contained serotype 7 and 9 isolates. Genetic similarity was observed between serotype 7 and serotype 2 isolates that do not express muramidase released protein (MRP and EF (MRP-EF-, suggesting these isolates originated from a common founder. Profiles of 25 putative virulence-associated genes of S. suis were determined among the 55 isolates. Presence of all 25 genes was shown for cluster A isolates, whereas cluster B isolates lacked one or more putative virulence genes. Divergence of S. suis isolates was further studied based on the presence of 39 regions of difference. Conservation of genes was evaluated by the definition of a core genome that contained 78% of all ORFs in P1/7. Conclusions In conclusion, we show that CGH is a valuable method to study distribution of genes or gene clusters among isolates in detail, yielding information on genetic similarity, and virulence traits of S. suis isolates.
Nomoto, R; Maruyama, F; Ishida, S; Tohya, M; Sekizaki, T; Osawa, Ro
In order to clarify the taxonomic position of serotypes 20, 22 and 26 of Streptococcus suis, biochemical and molecular genetic studies were performed on isolates (SUT-7, SUT-286(T), SUT-319, SUT-328 and SUT-380) reacted with specific antisera of serotypes 20, 22 or 26 from the saliva of healthy pigs as well as reference strains of serotypes 20, 22 and 26. Comparative recN gene sequencing showed high genetic relatedness among our isolates, but marked differences from the type strain S. suis NCTC 10234(T), i.e. 74.8-75.7 % sequence similarity. The genomic relatedness between the isolates and other strains of species of the genus Streptococcus, including S. suis, was calculated using the average nucleotide identity values of whole genome sequences, which indicated that serotypes 20, 22 and 26 should be removed taxonomically from S. suis and treated as a novel genomic species. Comparative sequence analysis revealed 99.0-100 % sequence similarities for the 16S rRNA genes between the reference strains of serotypes 20, 22 and 26, and our isolates. Isolate STU-286(T) had relatively high 16S rRNA gene sequence similarity with S. suis NCTC 10234(T) (98.8 %). SUT-286(T) could be distinguished from S. suis and other closely related species of the genus Streptococcus using biochemical tests. Due to its phylogenetic and phenotypic similarities to S. suis we propose naming the novel species Streptococcus parasuis sp. nov., with SUT-286(T) ( = JCM 30273(T) = DSM 29126(T)) as the type strain.
郑和平; SylviaBruisten; 何玉山; 黄进梅; 吴兴中
Objectives: To develop a multi-nested polymerase chain reaction in an assay to detect early Treponema pallidum and Haemophilus ducreyi DNA in the swabs of genital ulcers. Methods: Four pairs of outer and inner primers, specific to the basic membrane protein gene of Treponema pallidum and to the 16s rRNA gene of H ducreyi were synthesized. The multi-nested PCR was developed and applied to detect Treponema pallidum and Haemophilus dicreyi in clinical swabs. Result: The two samples of standard strains of Haemophilus ducreyi and one Treponema pallidum were amplified and showed 309-bp rRNA gene of Haemophilus ducreyi and 506-bp DNA of Treponema palidum, respectively. Out of 51 samples of genital ulcer detected, 29 showed Treponemapallidum positive product and noHaemophilus ducreyi DNA was found. Conclusion: The multi-nested PCR for Treponema pallidum and Haemophilus ducreyi could be useful for early detection and distinguishing diagnosis between syphilis and chancroid.
Full Text Available The epidemic aspects of swine infections caused by Streptococcus suis were studied, focusing mainly on the occurrence of several serotypes. A total of 323 samples of S. suis were isolated from clinically ill animals, serotyped according to the co-agglutination procedure, and analyzed. The serotyping revealed that S. suis was present in several Brazilian states. The largest number was isolated from the states of Minas Gerais (62.5%, São Paulo (10.8%, and Paraná (9.3%. Serotype 2 was the most frequent (61.0%, followed by the serotypes 1, 3, 4, 7, and 8. The largest number of isolations was obtained from the brain (60.1%, followed by the lungs (10.4%. About 9.4% of the cases were due to septicemia.Estudaram-se os aspectos epidêmicos das infecções de suínos causadas por Streptococcus suis, enfocando, principalmente, a ocorrência de diferentes sorotipos. Foram analisadas 323 amostras isoladas de animais clinicamente doentes, as quais foram sorotipadas de acordo com o procedimento de co-aglutinação. Foi verificado que S. suis está presente em vários estados brasileiros e o maior número de isolados originou-se dos estados de Minas Gerais (62,5%, São Paulo (10,8% e Paraná (9,3%. O sorotipo 2 foi o mais freqüente (61.0%, seguido pelos sorotipos 1, 3, 4, 7 e 8. Os isolamentos foram obtidos principalmente de cérebro (60,1% e pulmões (10,4%. Os casos de septicemia representaram 9,4%.
Marrs Carl F
Full Text Available Abstract Background Although non-typeable (NT Haemophilus influenzae and Haemophilus haemolyticus are closely related human commensals, H. haemolyticus is non-pathogenic while NT H. influenzae is an important cause of respiratory tract infections. Phase-variable phosphorylcholine (ChoP modification of lipooligosaccharide (LOS is a NT H. influenzae virulence factor that, paradoxically, may also promote complement activation by binding C-reactive protein (CRP. CRP is known to bind more to ChoP positioned distally than proximally in LOS, and the position of ChoP within LOS is dictated by specific licD alleles (designated here as licDI, licDIII, and licDIV that are present in a lic1 locus. The lic1 locus contains the licA-licD genes, and ChoP-host interactions may also be influenced by a second lic1 locus that allows for dual ChoP substitutions in the same strain, or by the number of licA gene tetranucleotide repeats (5'-CAAT-3' that reflect phase-variation mutation rates. Results Using dot-blot hybridization, 92% of 88 NT H. influenzae and 42.6% of 109 H. haemolyticus strains possessed a lic1 locus. Eight percent of NT H. influenzae and none of the H. haemolyticus strains possessed dual copies of lic1. The licDIII and licDIV gene alleles were distributed similarly (18-22% among the NT H. influenzae and H. haemolyticus strains while licDI alleles were present in 45.5% of NT H. influenzae but in less than 1% of H. haemolyticus strains (P H. influenzae had an average of 26.8 tetranucleotide repeats in licA compared to14.8 repeats in H. haemolyticus (P H. influenzae strains that possessed a licDIII allele had increased numbers of repeats compared to NT H. influenzae with other licD alleles (P Conclusions These data demonstrate that genetic similarities and differences of ChoP expression exist between NT H. influenzae and H. haemolyticus and strengthen the hypothesis that, at the population level, these differences may, in part, provide an advantage in
VACCINE INFORMATION STATEMENT Hib Vaccine ( Haemophilus Influenzae Type b) What You Need to Know Many Vaccine Information Statements are available in Spanish and other languages. See www. immunize. ...
Sánchez, L; Leranoz, S; Puig, M; Lorén, J G; Nikaido, H; Viñas, M
Strains of the facultative anaerobe Haemophilus influenzae, both type b and non typable strains, are frequently multiresistant. The measurement of the antibiotic permeability of Haemophilus influenzae outer membrane (OM) shows that antibiotics can cross through the OM easily. Thus, enzymatic activity or efflux pumps could be responsible for multiresistance. An efflux system closely related to AcrAB of Escherichia coli is present in Haemophilus influenzae. However, their role in multiresistance seems irrelevant. Classical mechanisms such as plasmid exchange seems to be playing a major role in the multidrug resistance in Haemophilus influenzae.
Winterhoff, Nora; Goethe, Ralph; Gruening, Petra; Valentin-Weigand, Peter
Streptococcus suis (S. suis) is an important pathogen in pigs and has to overcome strict iron limitations in its host environment. Here, we studied iron-restricted growth of a highly virulent S. suis strain in vitro at aerobic and CO2-enriched growth conditions. At both conditions, depleting of iron in the culture medium with nitrilotriacetic acid (NTA) resulted in decreased growth rates and down regulation of several proteins. Sensitivity to NTA was significantly higher at aerobic versus CO2-enriched conditions. Growth could not be restored by addition of host iron sources such as ferritin, hemin, hemoglobin, lactoferrin or transferrin. Accordingly, S. suis was not able to produce detectable amounts of siderophores. On the other hand, growth at iron-restricted conditions was fully restored by addition of Mn2+ (at aerobic and CO2-enriched conditions) or Mg2+ (only at CO2-enriched conditions). In conclusion our results suggest that, unlike many other bacteria, S. suis adapts to iron restricted conditions by a change in its metabolism in order to replace Fe2+ by Mn2+ or Mg2+ rather than by expressing specific iron uptake systems.
Full Text Available Streptococcus suis (S. suis is a crucial zoonotic pathogen which causes severe diseases in humans and pigs. Biofilms of S. suis can induce persistent infections which are harder to treat. Sub-minimal inhibitory concentration (sub-MIC of tylosin can inhibit biofilm formation in bacteria. By using iTRAQ strategy, we compared the protein expression profiles of S. suis grown with sub-MIC tylosin treatment or no treatement. The result showed that 96 proteins expression were changed with 77 up-regulated and 19 down-regulated proteins. Several metabolism proteins (such as phosphoglycerate kinase, as well as cell surface proteins (such as ABC transporter proteins, were found to be involved in biofilm formation. Overall, our results indicated that S. suis metabolic regulation, cell surface proteins, and virulence proteins appear to be of importance in biofilm growth by sub-MIC tylosin treated. Thus, our data analyzed rough regulation of biofilm formation that lay the foundation for the future research of mechanism and targets.
Full Text Available Streptococcus suis is an important bacterial swine pathogen and a zoonotic agent. Recently, two surface proteins of S. suis, Fhb and Fhbp, have been described for their capacity to bind factor H—a soluble complement regulatory protein that protects host cells from complement-mediated damages. Results obtained in this study showed an important role of host factor H in the adhesion of S. suis to epithelial and endothelial cells. Both Fhb and Fhbp play, to a certain extent, a role in such increased factor H-dependent adhesion. The capsular polysaccharide (CPS of S. suis, independently of the presence of its sialic acid moiety, was also shown to be involved in the recruitment of factor H. However, a triple mutant lacking Fhb, Fhbp and CPS was still able to recruit factor H resulting in the degradation of C3b in the presence of factor I. In the presence of complement factors, the double mutant lacking Fhb and Fhbp was similarly phagocytosed by human macrophages and killed by pig blood when compared to the wild-type strain. In conclusion, this study suggests that recruitment of factor H to the S. suis cell surface is multifactorial and redundant.
Roy, David; Grenier, Daniel; Segura, Mariela; Mathieu-Denoncourt, Annabelle; Gottschalk, Marcelo
Streptococcus suis is an important bacterial swine pathogen and a zoonotic agent. Recently, two surface proteins of S. suis, Fhb and Fhbp, have been described for their capacity to bind factor H-a soluble complement regulatory protein that protects host cells from complement-mediated damages. Results obtained in this study showed an important role of host factor H in the adhesion of S. suis to epithelial and endothelial cells. Both Fhb and Fhbp play, to a certain extent, a role in such increased factor H-dependent adhesion. The capsular polysaccharide (CPS) of S. suis, independently of the presence of its sialic acid moiety, was also shown to be involved in the recruitment of factor H. However, a triple mutant lacking Fhb, Fhbp and CPS was still able to recruit factor H resulting in the degradation of C3b in the presence of factor I. In the presence of complement factors, the double mutant lacking Fhb and Fhbp was similarly phagocytosed by human macrophages and killed by pig blood when compared to the wild-type strain. In conclusion, this study suggests that recruitment of factor H to the S. suis cell surface is multifactorial and redundant.
Koczula, Anna; Jarek, Michael; Visscher, Christian; Valentin-Weigand, Peter; Goethe, Ralph; Willenborg, Jörg
Streptococcus suis is a zoonotic pathogen that can cause severe pathologies such as septicemia and meningitis in its natural porcine host as well as in humans. Establishment of disease requires not only virulence of the infecting strain but also an appropriate metabolic activity of the pathogen in its host environment. However, it is yet largely unknown how the streptococcal metabolism adapts to the different host niches encountered during infection. Our previous isotopologue profiling studies on S. suis grown in porcine blood and cerebrospinal fluid (CSF) revealed conserved activities of central carbon metabolism in both body fluids. On the other hand, they suggested differences in the de novo amino acid biosynthesis. This prompted us to further dissect S. suis adaptation to porcine blood and CSF by RNA deep sequencing (RNA-seq). In blood, the majority of differentially expressed genes were associated with transport of alternative carbohydrate sources and the carbohydrate metabolism (pentose phosphate pathway, glycogen metabolism). In CSF, predominantly genes involved in the biosynthesis of branched-chain and aromatic amino acids were differentially expressed. Especially, isoleucine biosynthesis seems to be of major importance for S. suis in CSF because several related biosynthetic genes were more highly expressed. In conclusion, our data revealed niche-specific metabolic gene activity which emphasizes a selective adaptation of S. suis to host environments.
Bai, Jingwen; Yang, Yanbei; Wang, Shuai; Gao, Lingfei; Chen, Jianqing; Ren, Yongzhi; Ding, Wenya; Muhammad, Ishfaq; Li, Yanhua
Streptococcus suis (S. suis) is a zoonotic pathogen that causes severe disease symptoms in pigs and humans. Syringa oblata Lindl. distributed in the middle latitudes of Eurasia and North America were proved as the most development potential of Chinese Medicine. In this study, biofilm formation by S. suis decreased after growth with 1/2 MIC, 1/4 MIC, or 1/8 MIC of Syringa oblata Lindl. aqueous extract and rutin. Scanning electron microscopy analysis revealed the potential effect of Syringa oblata Lindl. aqueous extract and rutin against biofilm formation by S. suis. Using iTRAQ technology, comparative proteomic analyses was performed at two conditions: 1/2 MIC of Syringa oblata Lindl. aqueous extract treated and non-treated cells. The results revealed the existence of 28 proteins of varying amounts. We found that the majority of the proteins were related to cell growth and metabolism. We also found that Syringa oblata Lindl. Aqueous extract affected the synthesis enzymes. In summary, Syringa oblata Lindl. aqueous extract might be used to inhibit the biofilm formation effectively by S. suis, and the active ingredients of the Syringa oblate Lindl. aqueous extract is rutin. The content of rutin is 9.9 ± 0.089 mg/g dry weight. PMID:28194111
Fabisiak, M; Kita, J; Jedryczko, R; Binek, M
Knowledge of virulence factors of Streptococcus suis is limited. Several virulence factor candidates have been proposed, among them suilysin, which is responsible for a toxic effect on epithelial cells. The aim of this study was to detect the suilysin gene sequence in Streptococcus suis strains of various origin. In total 63 Streptococcus suis isolates were investigated. Forty four of them originated from tissues of streptococcosis affected animals. The remaining 19 strains were isolated from tonsils of healthy carrier pigs. Suilysin gene specific sequence was detected in 79% of the strains tested. In isolates obtained from pigs with signs of streptococcosis this gene sequence was recorded in 85% of cases. In Streptococcus suis strains isolated from healthy carrier pigs the suilysin gene was detected in 63% of the isolates. It seems that suilysin toxic activity is only one of the many steps involved in the pathogenesis of Streptococcus suis infection and that strain's virulence cannot be stated only on the basis of suilysin gene sequence presence.
Giacometti, Federica; Salas-Massó, Nuria; Serraino, Andrea; Figueras, Maria José
During a survey in a dairy plant in Italy, the second strain (strain FG 206) of Arcobacter suis described in the literature was isolated from raw water buffalo milk. The objective of this study was to confirm the species identification, better define the species by comparing its characteristics with those of the reference strain (F41(T) = CECT 7833(T) = LMG 26152(T)) and to investigate its potential clinical relevance by detecting the virulence gene pattern of the new strain. Phenotypical characterization and 16S rRNA-RFLP gave a complete overlap of results for the two strains. As expected, an RFLP pattern common to A. suis and Arcobacter defluvii was obtained by MseI endonuclease digestion, and a pattern specific for A. suis was obtained by BfaI endonuclease digestion. 16S rRNA sequencing and multilocus phylogenetic analysis (MLPA) showed a robust relatedness of strain FG 206 to the A. suis type strain F41(T). The recovery of strain FG 206 from a dairy plant shows that this species of Arcobacter is present in the food chain. Like the type strain recovered from pig meat, the species A. suis may not be confined to a single type of food.
Käser, Tobias; Cnudde, Thomas; Hamonic, Glenn; Rieder, Meghanne; Pasternak, J Alex; Lai, Ken; Tikoo, Suresh K; Wilson, Heather L; Meurens, François
Human ocular Chlamydia trachomatis infections can lead to trachoma, the major cause of infectious blindness worldwide. Trachoma control strategies are very helpful but logistically challenging, and a trachoma vaccine is needed but not available. Pigs are a valuable large animal model for various immunological questions and could facilitate the study of human ocular chlamydial infections. In addition, a recent study identified the zoonotic potential of Chlamydia suis, the natural pathogen of pigs. In terms of the One Health Initiative, understanding the host-pathogen-interactions and finding a vaccine for porcine chlamydia infections would also benefit human health. Thus, we infected the porcine retinal cell line VIDO R1 with C. suis and analyzed the chlamydial life cycle and the innate immune response of the infected cells. Our results indicate that C. suis completes its life cycle in VIDO R1 cells within 48 h, comparable to C. trachomatis in humans. C. suis infection of VIDO R1 cells led to increased levels of various innate immune mediators like pathogen recognition receptors, cytokines and chemokines including IL6, TNFα, and MMP9, also most relevant in human C. trachomatis infections. These results illustrate the first steps in the host-pathogen-interactions of ocular C. suis infections in pigs and show their similarity to C. trachomatis infections in humans, justifying further testing of pigs as an animal model for human trachoma.
Full Text Available Streptococcus suis is a zoonotic pathogen that can cause severe pathologies such as septicemia and meningitis in its natural porcine host as well as in humans. Establishment of disease requires not only virulence of the infecting strain but also an appropriate metabolic activity of the pathogen in its host environment. However, it is yet largely unknown how the streptococcal metabolism adapts to the different host niches encountered during infection. Our previous isotopologue profiling studies on S. suis grown in porcine blood and cerebrospinal fluid (CSF revealed conserved activities of central carbon metabolism in both body fluids. On the other hand, they suggested differences in the de novo amino acid biosynthesis. This prompted us to further dissect S. suis adaptation to porcine blood and CSF by RNA deep sequencing (RNA-seq. In blood, the majority of differentially expressed genes were associated with transport of alternative carbohydrate sources and the carbohydrate metabolism (pentose phosphate pathway, glycogen metabolism. In CSF, predominantly genes involved in the biosynthesis of branched-chain and aromatic amino acids were differentially expressed. Especially, isoleucine biosynthesis seems to be of major importance for S. suis in CSF because several related biosynthetic genes were more highly expressed. In conclusion, our data revealed niche-specific metabolic gene activity which emphasizes a selective adaptation of S. suis to host environments.
Hayashida, H.; Poulsen, Knud; Kilian, Mogens
. actinomycetemcomitans strains examined harboured a single genomic sequence with homology to the hgpA gene encoding haemoglobin-binding protein A in Haemophilus influenzae. However, in all three strains belonging to the JP2 clone and in one serotype e strain hgpA was a pseudogene. Seven other strains possessed...
Christensen, Henrik; Bisgaard, Magne; Angen, Øystein;
Phenotypic characterization of bacteria from diseased and healthy horses identified 18 isolates as Bisgaard taxon 9 and 11 isolates as Actinobacillus lignieresii. All strains of taxon 9 were alpha-galactosidase- and raffinose-positive and showed variable fermentation of (+)L-arabinose and (-)D-sorbitol....... Strains of A. lignieresii were negative for these characteristics, with the exception of raffinose. Two strains from the (-)D-sorbitol-negative group of taxon 9 showed a 16S rRNA similarity of 99.6%, while 99.5% similarity was found between two strains of the (-)D-sorbitol-positive group. DNA......-DNA hybridization between the two strains representing the (-)D-sorbitol-negative group showed 98% binding, and their closest relationship was to a strain of A. lignieresii (64%). The two strains of the (-)D-sorbitol-positive group showed 83% binding and were related to the (-)D-sorbitol-negative group at a 76% DNA...
Espinoza-Mellado, María del Rosario; Reyes-Picaso, Carolina; Garcés-Pérez, Miriam S; Jardón-Serrano, Cynthia V; López-Villegas, Edgar O; Giono-Cerezo, Silvia
The MAP-LC3 system regulates the intracellular formation of autophagy-associated vacuoles. These vacuoles contain the LC3 protein; thus it has been utilized as a marker to identify autophagosomes. The aim of our study was to investigate whether Haemophilus influenzae strains and their supernatants could activate autophagy in human larynx carcinoma cell line (HEp-2). We demonstrate that higher expression of the LC3B-II protein was induced, particularly by nontypeable Haemophilus influenzae (NTHi) 49766 and by supernatants, containing <50 kDa proteins, of both strains. Ultrastructural studies demonstrate vacuoles with a double membrane and/or membrane material inside, showing similar features to those of autophagic vacuoles. Together, our findings demonstrate that H. influenzae strains and their supernatants trigger an autophagic process.
Abeck, D; Freinkel, A L; Korting, H C; Szeimis, R M; Ballard, R C
To gain information on the specific composition of the inflammatory infiltrate of genital ulcers caused by Haemophilus ducreyi, biopsies of 6 genital ulcers which were diagnosed as chancroid on clinical and microbiological grounds were subjected to immunohistochemical investigations after conventional haematoxylineosin staining. A variety of antibodies reactive against B- and T-cells, plasma cells and granulocytes were used with each tissue sections. The lymphocytic infiltrate of chancroid ulcers consisted of both B- and T-lymphocytes and showed a cluster-like formation. B-lymphocytes were preferentially localized perivascularly in the middle layer, T-lymphocytes mainly in the deep layer of the inflamed oedematous tissue. Results stress the importance of both B- and T-cell mediated immune responses in Haemophilus ducreyi infection.
Laan, Lisa C; Williams, Andrew R; Stavenhagen, Kathrin
Clinical trials have shown that administration of the nematode Trichuris suis can be beneficial in treating various immune disorders. To provide insight into the mechanisms by which this worm suppresses inflammatory responses, an active component was purified from T. suis soluble products (TsSPs)...
Willemse, N.; Howell, K.J.; Weinert, L.A.; Heuvelink, A.; Pannekoek, Y.; Wagenaar, J.A.; Smith, H.E.; Ende, Van Der A.; Schultsz, C.
Streptococcus suis is a zoonotic swine pathogen and a major public health concern in Asia, where it emerged as an important cause of bacterial meningitis in adults. While associated with food-borne transmission in Asia, zoonotic S. suis infections are mainly occupational hazards elsewhere. To ide
Hsueh, K-J; Lee, J-W; Hou, S-M; Chen, H-S; Chang, T-C; Chu, C-Y
Streptococcus suis (S. suis) can be classified into 33 serotypes based on the structure of capsular polysaccharides. Recent research indicated that a new surface protein designated as Sao (surface antigen one) reacts with 30 serotypes of convalescent-phase sera during S. suis infections, which makes Sao a good potential antigen for developing S. suis vaccines. The objectives of this study were to produce recombinant Sao-L protein (rSao-L) from a strain of S. suis serotype 2 by a prokaryotic expression system in bioreactors and to use rSao-L as the antigen for a S. suis vaccine in mouse and swine models. The antibody titres in mice and pigs immunized with rSao-L were significantly (P bacteria, the anatomical lesions in pigs immunized with rSao-L were reduced by 60%. These data indicated that immunization with rSao-L can confer cross-serotype protection against S. suis. Moreover, percentages of CD8(+) and CD4(+) /CD8(+) double-positive T cells in immunized pigs were significantly higher than those of the control group (P < 0.01). Using bioreactors to produce rSao-L as the antigen for S. suis vaccines may broaden protective efficacy and reduce production costs.
Full Text Available Streptococcus suis is an important swine pathogen and emerging zoonotic agent worldwide causing meningitis, endocarditis, arthritis and septicemia. Among the 29 serotypes identified to date, serotype 2 is mostly isolated from diseased pigs. Although several virulence mechanisms have been characterized in S. suis, the pathogenesis of S. suis infections remains only partially understood. This study focuses on the response of S. suis P1/7 to sub-inhibitory concentrations of amoxicillin. First, capsule expression was monitored by qRT-PCR when S. suis was cultivated in the presence of amoxicillin. Then, the pro-inflammatory potential of S. suis P1/7 culture supernatants or whole cells conditioned with amoxicillin was evaluated by monitoring the activation of the NF-κB pathway in monocytes and quantifying pro-inflammatory cytokines secreted by macrophages. It was found that amoxicillin decreased capsule expression in S. suis. Moreover, conditioning the bacterium with sub-inhibitory concentrations of amoxicillin caused an increased activation of the NF-κB pathway in monocytes following exposure to bacterial culture supernatants and to a lesser extent to whole bacterial cells. This was associated with an increased secretion of pro-inflammatory cytokines (CXCL8, IL-6, IL-1β by macrophages. This study identified a new mechanism by which S. suis may increase its inflammatory potential in the presence of sub-inhibitory concentrations of amoxicillin, a cell wall-active antibiotic, thus challenging its use for preventive treatments or as growth factor.
Ngo, T.H; Tran, T.B.C.; Tran, T.T.N.; Nguyen, V.D.; Campbell, J.; Pham, H.A.; Huynh, H.T.; Nguyen, V.V.C.; Bryant, J.E.; Tran, T.H.; Farrar, J.; Schultsz, C.
Streptococcus suis is a pathogen of major economic significance to the swine industry and is increasingly recognized as an emerging zoonotic agent in Asia. In Vietnam, S. suis is the leading cause of bacterial meningitis in adult humans. Zoonotic transmission is most frequently associated with serot
Greeff, de A.; Benga, A.; Wichgers, P.J.; Valentin-Weigand, P.; Rebel, J.M.J.; Smith, H.E.
Interaction of Streptococcus suis with primary porcine alveolar macrophages was Studied using transcriptomics. Transcriptional response of macrophages to two different S. suis strains was studied: wild-type S10 that is resistant to phagocytosis, and its non-encapsulated mutant that is phagocytosed e
Jungersen, Gregers; Sørensen, Vibeke; Giese, Steen Bjørck
with responses of B. suis biovar 2-inoculated pigs. FPSR were limited to 2-9 weeks post-YeO:9 inoculation, while B. suis-infected pigs were test-positive throughout the 21-week period of investigation. Although YeO:9-inoculated pigs exhibited FPSR in Brucella tests for a limited period of time, the serological...
Kristien De Puysseleyr
Full Text Available Pigs are the natural host for Chlamydia suis, a pathogen which is phylogenetically highly related to the human pathogen C. trachomatis. Chlamydia suis infections are generally treated with tetracyclines. In 1998, tetracyline resistant C. suis strains emerged on U.S. pig farms and they are currently present in the Belgian, Cypriote, German, Israeli, Italian and Swiss pig industry. Infections with tetracycline resistant C. suis strains are mainly associated with severe reproductive failure leading to marked economical loss. We developed a sensitive and specific TaqMan probe-based C. suis real-time PCR for examining clinical samples of both pigs and humans. The analytical sensitivity of the real-time PCR is 10 rDNA copies/reaction without cross-amplifying DNA of other Chlamydia species. The PCR was successfully validated using conjunctival, pharyngeal and stool samples of slaughterhouse employees, as well as porcine samples from two farms with evidence of reproductive failure and one farm without clinical disease. Chlamydia suis was only detected in diseased pigs and in the eyes of humans. Positive humans had no clinical complaints. PCR results were confirmed by culture in McCoy cells. In addition, Chlamydia suis isolates were also examined by the tet(C PCR, designed for demonstrating the tetracycline resistance gene tet(C. The tet(C gene was only present in porcine C. suis isolates.
De Puysseleyr, Kristien; De Puysseleyr, Leentje; Geldhof, Julie; Cox, Eric; Vanrompay, Daisy
Pigs are the natural host for Chlamydia suis, a pathogen which is phylogenetically highly related to the human pathogen C. trachomatis. Chlamydia suis infections are generally treated with tetracyclines. In 1998, tetracyline resistant C. suis strains emerged on U.S. pig farms and they are currently present in the Belgian, Cypriote, German, Israeli, Italian and Swiss pig industry. Infections with tetracycline resistant C. suis strains are mainly associated with severe reproductive failure leading to marked economical loss. We developed a sensitive and specific TaqMan probe-based C. suis real-time PCR for examining clinical samples of both pigs and humans. The analytical sensitivity of the real-time PCR is 10 rDNA copies/reaction without cross-amplifying DNA of other Chlamydia species. The PCR was successfully validated using conjunctival, pharyngeal and stool samples of slaughterhouse employees, as well as porcine samples from two farms with evidence of reproductive failure and one farm without clinical disease. Chlamydia suis was only detected in diseased pigs and in the eyes of humans. Positive humans had no clinical complaints. PCR results were confirmed by culture in McCoy cells. In addition, Chlamydia suis isolates were also examined by the tet(C) PCR, designed for demonstrating the tetracycline resistance gene tet(C). The tet(C) gene was only present in porcine C. suis isolates.
Mario Julio Avila-Campos
Full Text Available Haemolytic activity of sixty nine Actinobacillus actinomycetemcomitans strains on different animal and human blood types was examined by using a trypticase soy agar supplemented with yeast extract (0.5%. Blood types used were: rabbit, sheep and human (A, Rh+; A, Rh-; B, Rh+; B, Rh-; O, Rh+; O, Rh-; AB, Rh+; AB, Rh- groups. Plates were inoculated and, incubated in microaerophilic conditions, at 37ºC, for 48 h. The haemolytic activity of the tested strains was characterized as alpha-haemolysis. Only two isolates were not haemolytic on all blood types (2.9%, two strains were haemolytic only on human blood (one strain on AB, Rh+ group and another one on A, Rh+ and AB, Rh+ groups. No specificity between haemolysin produced by the tested strains and blood type was observed.A atividade hemolítica de 69 cepas de Actinobacillus actinomycetemcomitans foi determinada em diferentes tipos de sangue animal e humano, usando como meio base ágar de soja tripticaseina, suplementado com extrato de levedura (0,5%. Foram utilizados sangue de coelho, carneiro e humano (grupos A, Rh+; A, Rh-; B, Rh+; B, Rh-; O, Rh+; O, Rh-; AB, Rh+ e AB, Rh-. As placas foram inoculadas e, incubadas em condições de microaerofilia, a 37ºC, por 48 h. A atividade hemolítica das cepas testadas foi caracterizada como alfa-hemólise. Somente dois (2,9% isolados não hemolisaram todos os tipos sanguíneos, duas cepas hemolisaram somente sangue humano (uma o grupo AB, Rh+ e outra os grupos A, Rh+ e AB, Rh+. Não foi observada alguma especificidade entre as hemolisinas produzidas e os tipos de sangue utilizados.
Perry, Malcolm B.; Angen, Øystein; MacLean, Leann L.
Atypical Actinobacillus pleuropneumoniae serotype 13 strains present in North America are described here for the first time. Different from serotype 13 strains described in Europe, North America strains are biotype I and antigenically related to both, serotypes 13 and 10. Chemical and structural...... and structurally identical with that of the reference strain of A. pleuropneumoniae serotype 10. The O-PS was characterized as a homopolymer of 1,2 linked β-d-galactofuranosyl residues, a structure unrelated to that of the O-PS produced by the reference strain of serotype 13. Strains from Canada and United States....... pleuropneumoniae serotype 10....
Fussing, V.; Barfod, Kristen; Nielsen, R.
The aim of the present study was to evaluate ribotyping as an epidemiological tool for Actinobacillus pleuropneumoniae and apply the method in studies of A. pleuropneumoniae infections in Danish pig herds. The evaluation of ribotyping was based on the 13 international reference strains and 106......, and the discriminatory power was between 0.85-0.89. The relatively low discriminatory power was caused by four predominant types, containing 61% of the isolates. The typing system was applied in studies of routes of infection of specific pathogen-free (SPF) pig herds and included 112 strains of A. pleuropneumoniae...
Jensen, Tim Kåre; Boye, Mette; Hagedorn-Olsen, T.
Necrotizing osteomyelitis and fibrinopurulent arthritis with isolation of Actinobacillus pleuropneumoniae serotype 2 is reported in two pigs from a herd with lameness and mild coughing problems among 8 to 12-week-old pigs. Application of fluorescent in situ hybridization targeting 16S ribosomal RNA...... of A. pleuropneumoniae in formalin-fixed tissue was performed to verify the association of A. pleuropneumoniae with the bone and joint lesions. By in situ hybridization A. pleuropneumoniae was demonstrated as multiple microcolonies or single cells dispersed in focal fibrinonecrotizing pleuropneumonia...
Berger, Sanne Schou; Lauritsen, Klara Tølbøl; Boas, Ulrik
We have developed and made a preliminary validation of a bead-based multiplexed immunoassay for simultaneous detection of porcine serum antibodies to Actinobacillus pleuropneumoniae serovars 1, 2, 6, 7, and 12. Magnetic fluorescent beads were coupled with A. pleuropneumoniae antigens and tested...... Pathogen Free system. Assay specificities and sensitivities as well as the corresponding cutoff values were determined using receiver operating characteristic (ROC) curve analysis, and the A. pleuropneumoniae multiplex assay showed good correlation with the in-house ELISAs and CF tests with areas under ROC...
Pinto J., Chris; Laboratorio de Microbiología y Parasitología Veterinaria, Facultad de Medicina Veterinaria, Universidad Nacional Mayor de San Marcos, Lima-Perú.; Torres A., Marlon; Laboratorio de Zootecnia y Producción Agropecuaria, Facultad de Medicina Veterinaria, Universidad Nacional Mayor de San Marcos, Lima-Perú.; Falcón P., Néstor; Laboratorio de Medicina Veterinaria Preventiva, Facultad de Medicina Veterinaria, Universidad Nacional Mayor de San Marcos, Lima; Morales C., Siever; Laboratorio de Microbiología y Parasitología Veterinaria, Facultad de Medicina Veterinaria, Universidad Nacional Mayor de San Marcos, Lima
El objetivo del estudio fue determinar la frecuencia de anticuerpos contra la toxina ApxIV de Actinobacillus pleuropneumoniae, causante de pleuroneumonía porcina en 10 granjas porcinas tecnificadas de los departamentos de Arequipa, Lima, Ica y La Libertad. Se colectaron muestras de sangre de porcinos de las etapas de crecimiento y acabado (30 por granja) y se analizaron mediante la prueba de ELISA indirecta con un kit comercial. El 23.7% (71/300) de los animales presentaron anticuerpos contra...
KASUYA, Kazufumi; MANCHANAYAKE, Tilusha; UENOYAMA, Kei; KAWA, Sayaka; TAKAYAMA, Kou; IMAI, Naoto; SHIBAHARA, Tomoyuki
An imported crossbred Angus beef steer aged eight to twelve months died suddenly on the eighth day of a quarantine period in Japan. Gross examination showed the peritoneum and mesentery consisted of numerous nodules of various sizes. Histological examination revealed chronic suppurative granulomatous peritonitis with eosinophilic rosettes surrounding colonies of Gram-negative bacilli. The bacteria isolated from the nodules were confirmed to be Actinobacillus lignieresii based on the results of 16S rRNA gene sequencing and immunohistochemistry. Antibiotic sensitivity testing showed that the isolate was resistant to penicillin. Thus, a diagnosis of atypical actinobacillosis caused by A. lignieresii was made. PMID:27773882
Lindeman, Zachary; Waggoner, Molly; Batdorff, Audra; Tricia L Humphreys
Background Haemophilus ducreyi is the bacterium responsible for the genital ulcer disease chancroid, a cofactor for the transmission of HIV, and it is resistant to many antibiotics. With the goal of exploring possible alternative treatments, we tested essential oils (EOs) for their efficacy as antimicrobial agents against H. ducreyi. Methods We determine the minimum inhibitory concentration (MIC) of Cinnamomum verum (cinnamon), Eugenia caryophyllus (clove) and Thymus satureioides (thyme) oil ...
Quorum signals are diffusible factors produced by bacteria that coordinate communal responses. For nontypeable Haemophilus influenzae (NTHi), a series of recent papers indicate that production and sensing of quorum signals are determinants of biofilm formation/maturation and persistence in vivo. In this mini-review I will summarize the current knowledge about quorum signaling/sensing by this organism, and identify specific topics for additional study.
Inzana, T J; Hensley, J; McQuiston, J; Lesse, A J; Campagnari, A A; Boyle, S M; Apicella, M A
The bovine-specific pathogen Haemophilus somnus is capable of undergoing structural and antigenic phase variation in its lipooligosaccharide (LOS) components after in vivo and in vitro passage. However, commensal isolates from the reproductive tract have not been observed to vary in phase (T. J. Inzana, R. P. Gogolewski, and L. B. Corbeil, Infect. Immun. 60:2943-2951, 1992). We now report that specific monoclonal antibodies (MAbs) to the LOSs of Haemophilus aegyptius, Neisseria gonorrhoeae, and Haemophilus influenzae, as well as H. somnus, reacted with some phase-variable epitopes in H. somnus LOS. All reactive MAbs bound to LOS components of about 4.3 kDa in the same H. somnus isolates, including a non-phase-varying strain. Following in vitro passage of a clonal variant of strain 738 that was nonreactive with the MAbs, 11.8% of young colonies shifted to a reactive phenotype. A digoxigenin-labelled 5'-CAATCAATCAATCAATCAATCAATCAAT-3' oligonucleotide probe hybridized to genomic DNA from strain 738 but did not react with DNA from a non-phase-varying strain. Sequence analysis of the gene containing 5'-CAAT-3' tandem sequences revealed 48% amino acid homology with the lex-2B gene-encoded protein of H. influenzae type b. Our results indicate that some LOS epitopes are conserved between H. somnus and other Haemophilus and Neisseria species, that LOS phase variation may occur at a high rate in some strains of H. somnus, and that phase variation may, in part, be due to 5'-CAAT-3' tandem sequences present in H. somnus genes.
WHITE, D C
White, D. C. (Rockefeller Institute, New York, N.Y.). Respiratory systems in hemin-requiring Haemophilus species. J. Bacteriol. 85:84-96. 1963.-If grown in Levinthal's medium or in proteose peptone medium with excess hemin, Haemophilus influenzae, H. aegyptius, and H. canis (H. haemoglobinophilus) form an electron-transport system consisting of six cytochromes and two respiratory flavoproteins. In proteose peptone, these species can greatly modify the composition of their electron-transport complex. With anaerobic incubation in the presence of nitrate, they produce increased amounts of cytochrome c(1) and the cytochrome oxidases a(1) and o. This anaerobic pattern is greatly exaggerated by growth under carbon monoxide, in which case large concentrations of cytochrome oxidase are produced. In the presence of the inhibitor secobarbital or of growth-limiting amounts of hemin, intermediate amounts of cytochromes and respiratory flavoproteins are formed. When only small amounts of hemin are present, these species grow but form no detectable cytochrome system. Catalase is the only hemoprotein found. Under these conditions, the addition of glucose induces the formation of a lactate oxidase flavoprotein if the system is incubated aerobically. This cytochromeless state also occurs when these species are grown in KCN or anaerobically without nitrate and with excess hemin. The ability of these species to modify the composition of the electron-transport system strongly suggests that this function unit is formed from individual components. Hemin-requiring Haemophilus species have a hemin-sparing compensatory mechanism that allows growth under conditions under which hemin-independent Haemophilus species will not grow.
Full Text Available Tradicionalmente el Haemophilus influenzae ha sido considerado un germen causante de infecciones en niños; en adultos se lo ha relacionado con Infecciones respiratorias, pero en los últimos tiempos se han descrito en ellos infecciones severas cuando hay algunos factores predisponentes. Se describe un paciente drogadicto de 30 años con cuadro de meningitis y artritis y prueba de látex y cultivo de LCR positivos para HaemophiIus influenzae, quien recibió tratamiento con ampicilina, 2 gramos Intravenosos cada 4 horas y evolucionó a la mejoría sin secuelas. Se plantea la necesidad de tener en cuenta al Haemophilus influenzae como patógeno del adulto y más en aquellas personas con factores predisponentes.
Haemophilus influenzae has traditionally been considered as an infectious agent that predominantly affects children; instead, in adults It has been Linked either to respiratory infections or to gevere infections occurring when predisposing factors are present. We describe a 30 year-old drug adict patient that presented with meningitis and arthritis; both latex test and cerebrospinal fluid culture were positive for Haemophilus influenzae. He was treated with ampicilin 2 gm, I. V. every four hours and improved without sequelae. This microorganism must be considered among those affecting adult patients specially when predisposing factors for infection are present.
Godek, C P; Cynamon, M H
Exogenous NAD, nicotinamide mononucleotide, or nicotinamide riboside is required for the growth of Haemophilus influenzae. These compounds have been defined as the V-factor growth requirement. We have previously shown that the internalization of nicotinamide riboside is energy dependent and carrier mediated with saturation kinetics. Thionicotinamide riboside, 3-pyridinealdehyde riboside, 3-acetylpyridine riboside, and 3-aminopyridine riboside were prepared from their corresponding NAD analogs...
Whitby, Paul W; Vanwagoner, Timothy M; Seale, Thomas W; Morton, Daniel J; Stull, Terrence L
Haemophilus influenzae requires either heme or a porphyrin and iron source for growth. Microarray studies of H. influenzae strain Rd KW20 identified 162 iron/heme-regulated genes, representing approximately 10% of the genome, with > or =1.5-fold changes in transcription in response to iron/heme availability in vitro. Eighty genes were preferentially expressed under iron/heme restriction; 82 genes were preferentially expressed under iron/heme-replete conditions.
Notani, N. K.; Setlow, J K
Weigle reactivation of ultraviolet-irradiated HPlc1 phage was observed after ultraviolet or mitomycin C treatment of Haemophilus influenzae cells. The amount of reactivation was considerably increased when the treated cells were incubated in growth medium before infection. The presence of chloramphenicol during this incubation abolished the reactivation. No mutation of this phage accompanied the reactivation. When cells were treated so as to produce a maximal reactivation of phage, neither re...
Mendoza, Alfredo; Laboratorio de Biología Molecular, Facultad de Farmacia y Bioquímica de la Universidad Nacional Mayor de San Marcos, Lima, Perú. Departamento de Investigación y Desarrollo, Bioservice SRL.; Koga, Ysabel; Departamento de Investigación y Desarrollo, Bioservice SRL.; Zavaleta, Amparo l.; Laboratorio de Biología Molecular, Facultad de Farmacia y Bioquímica de la Universidad Nacional Mayor de San Marcos, Lima, Perú.
Infectious Coriza (IC) is a disease of the upper respiratory tract of commerdal birds, is caused by Haemophilus paragallinarum, prevented through vaccines and treated by several antimicrobials. With the objective of determining the sensitivity of most used-anti Infectious Coriza antimicrobials, nineteen strains of H. paragallinarum isolated from beeders layer hens and broiler chickens with typical symptoms of IC, from different avian regions of Peru were used. The minimal inhibitory concentra...
Juul, Marie Louise; Johansen, Helle Krogh; Homøe, Preben
A healthy 23-year-old man was admitted under the diagnosis of acute epiglottitis. Flexible fiber laryngoscopic examination showed a swollen epiglottis with an abscess. Microbiologic swab showed Haemophilus parainfluenzae, non-haemolytic Streptococcus and non-haemolytic Streptococcus salivarius....... Only in 1984 a case of acute epiglottitis due to H. parainfluenzae has been described in the literature. Still, in this case we think that H. parainfluenzae was the most likely pathogen causing the abscess....
Weinert, Lucy A; Chaudhuri, Roy R; Wang, Jinhong; Peters, Sarah E; Corander, Jukka; Jombart, Thibaut; Baig, Abiyad; Howell, Kate J; Vehkala, Minna; Välimäki, Niko; Harris, David; Chieu, Tran Thi Bich; Van Vinh Chau, Nguyen; Campbell, James; Schultsz, Constance; Parkhill, Julian; Bentley, Stephen D; Langford, Paul R; Rycroft, Andrew N; Wren, Brendan W; Farrar, Jeremy; Baker, Stephen; Hoa, Ngo Thi; Holden, Matthew T G; Tucker, Alexander W; Maskell, Duncan J
Streptococcus suis causes disease in pigs worldwide and is increasingly implicated in zoonotic disease in East and South-East Asia. To understand the genetic basis of disease in S. suis, we study the genomes of 375 isolates with detailed clinical phenotypes from pigs and humans from the United Kingdom and Vietnam. Here, we show that isolates associated with disease contain substantially fewer genes than non-clinical isolates, but are more likely to encode virulence factors. Human disease isolates are limited to a single-virulent population, originating in the 1920, s when pig production was intensified, but no consistent genomic differences between pig and human isolates are observed. There is little geographical clustering of different S. suis subpopulations, and the bacterium undergoes high rates of recombination, implying that an increase in virulence anywhere in the world could have a global impact over a short timescale.
Deza, Gustavo; Martin-Ezquerra, Gemma; Gómez, Julià; Villar-García, Judit; Supervia, August; Pujol, Ramon M
To describe the clinical characteristics and therapeutic outcomes from male patients diagnosed of Haemophilus spp urethritis. A chart review of patients who presented to our hospital from January 2013 to December 2014 with symptoms of acute urethritis in which Haemophilus spp was isolated in their urethral samples was performed. Haemophilus spp was isolated in 52 out of 413 urethral samples (12.6%) received in our laboratory from patients with symptoms of acute urethritis during the study period. Seven cases corresponded to Haemophilus influenzae and 45 cases to Haemophilus parainfluenzae. The most common clinical presentation was mucopurulent urethral discharge (71%). Eight per cent were HIV-infected patients, and 60% were men who have sex with men. Haemophilus spp was isolated as a single pathogen in 6.8% (28 of 413) of cases. Seventeen per cent of Haemophilus spp were β-lactamase producers. All patients reported having practiced unprotected insertive oral sex the month before consultation, and five of them denied having had another sexual contact apart from this exposure. In all cases in which follow-up was available, empirical treatment achieved a complete clinical resolution. Haemophilus spp was considered a pathogen in at least 6.8% of the patients from the evaluated area. It affected men regardless their sexual orientation or HIV status. Unprotected oral sex could play a role in its transmission. The limitations of the study (small sample size and lack of a representative control group) do not allow to prove the true pathogenic role of Haemophilus spp in acute urethritis. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/
Yang, L; Yamamoto, K; Nishiumi, S; Nakamura, M; Matsui, H; Takahashi, S; Dohi, T; Okada, T; Kakimoto, K; Hoshi, N; Yoshida, M; Azuma, T
Helicobacter (H.) suis is capable of infecting various animals including humans, and H. suis infections can lead to gastric mucosa-associated lymphoid tissue (MALT) lymphoma. Recently, we reported that interferon-γ (IFN-γ) was highly expressed in the stomachs of H. suis-infected mice, but the direct relationship between the upregulation of IFN-γ expression and the formation of gastric lymphoid follicles after H. suis infection remains unclear. Here, we demonstrated that the IFN-γ produced by B cells plays an important role in the formation of gastric lymphoid follicles after H. suis infection. In addition, IFN-γ-producing B cells evoked gastric lymphoid follicle formation independent of T-cell help, suggesting that they are crucial for the development of gastric MALT induced by Helicobacter infection.
Nga, Tran Vu Thieu; Nghia, Ho Dang Trung; Tu, Le Thi Phuong; Diep, To Song; Mai, Nguyen Thi Hoang; Chau, Tran Thi Hong; Sinh, Dinh Xuan; Phu, Nguyen Hoan; Nga, Tran Thi Thu; Chau, Nguyen Van Vinh; Campbell, James; Hoa, Ngo Thi; Chinh, Nguyen Tran; Hien, Tran Tinh; Farrar, Jeremy; Schultsz, Constance
Streptococcus suis serotype 2 is an emerging zoonotic pathogen and is the main cause of acute bacterial meningitis in adult patients in Vietnam. We developed an internally controlled real-time PCR for detection of S. suis serotype 2 in cerebrospinal fluid (CSF) samples targeted at the cps2J gene. Sensitivity and specificity in culture-confirmed clinical samples were 100%. The PCR detected S. suis serotype 2 infection in 101 of 238 (42.4%) prospectively collected CSF samples, of which 55 (23%) were culture positive. Culture-negative but PCR-positive CSF samples were significantly associated with the use of antimicrobial agents before admission. S. suis serotype 2 infection was more common than infections with Streptococcus pneumoniae and Neisseria meningitidis combined. Our results strikingly illustrate the additional diagnostic value of PCR in patients who are pretreated with antimicrobial agents and demonstrate the extremely high prevalence of S. suis infections among Vietnamese adult patients with bacterial meningitis. PMID:21767702
Willemse, N; Howell, K J; Weinert, L A; Heuvelink, A; Pannekoek, Y; Wagenaar, J A; Smith, H E; van der Ende, A; Schultsz, C
Streptococcus suis is a zoonotic swine pathogen and a major public health concern in Asia, where it emerged as an important cause of bacterial meningitis in adults. While associated with food-borne transmission in Asia, zoonotic S. suis infections are mainly occupational hazards elsewhere. To identify genomic differences that can explain zoonotic potential, we compared whole genomes of 98 S. suis isolates from human patients and pigs with invasive disease in the Netherlands, and validated our observations with 18 complete and publicly available sequences. Zoonotic isolates have smaller genomes than non-zoonotic isolates, but contain more virulence factors. We identified a zoonotic S. suis clone that diverged from a non-zoonotic clone by means of gene loss, a capsule switch, and acquisition of a two-component signalling system in the late 19th century, when foreign pig breeds were introduced. Our results indicate that zoonotic potential of S. suis results from gene loss, recombination and horizontal gene transfer events.
Full Text Available Haemophilus vaginalis infection is a sexual transmitted disease in women. In the public health services, the proportional rate was 40% (Klein, 1994. Preliminary study in the one of the cancer clinic in Surabaya showed that 1.544 women (6.2% infected by Haemophilus vaginalis. So, need a study to assess the risk factor of Haemophylus vaginalis infection.This was a case control study. The case was all of the women who had Pap's smear examination in the one of cancer clinic in Surabaya at 2001 with Haemophillus vaginalis infection (47 women. Ratio case and control was 1:1. Control was conducted with matching in age and parity, used simple random sampling. Independent variables were woman characteristic (age, education level, income, job status, parity, and IUD client, level of knowledge and personal hygiene. Collecting data used intenview and tracer of the secondary data. To analyzed used OR with 95% CI.The risk factors of Haemophylus vaginalis infection were junior high school education level or lower (OR = 2.88, low income (OR = 17.32 and IUD client (OR = 4.29. The age above > 40 years old, job status, parity (> 3 children, the low level of knowledge and personal hygiene had no statistically significant.Knowledge about the risk factors can used to control the disease. Need the early detection in women with risk factors such as lower education level, low income and IUD Client. Key words: Risk factors, Haemophilus vaginalis infection
Silva, Luciana M G; Baums, Christoph G; Rehm, Thomas; Wisselink, Henk J; Goethe, Ralph; Valentin-Weigand, Peter
Definition of virulent Streptococcus suis strains is controversial. One successful approach for identification of virulent European strains is differentiation of capsular serotypes (or the corresponding cps types) and subsequent detection of virulence-associated factors, namely the extracellular factor (EF, epf), the muramidase-released protein (MRP, mrp) and the hemolysin suilysin (SLY, sly). In this work we present a novel multiplex PCR (MP-PCR) and an mrp variant PCR for identification and characterization of virulent S. suis strains. These new methods were used to identify association of disease with particular profiles of virulence-associated genes. The MP-PCR allowed identification of S. suis through detection of the housekeeping gene gdh, differentiation of four cps types (1, 2, 7 and 9), and detection of epf, mrp, sly and arcA (arginine deiminase from S. suis). Furthermore, this study describes the first PCR assay for differentiation of at least six mrp variants. Expression of the corresponding size variants of MRP was shown for four of the six mrp variants, but was undetectable for the two larger mrp variants in the particular strains investigated. The results of this study suggest that cps7 strains are associated with pneumonia and that variation of mrp is very pronounced among these strains. Gene profiles of invasive, pneumonia and carrier S. suis isolates by combination of PCR assays allowed differentiation of 24 different genotypes among cps1, 2, 7 and 9 strains. Forty-five percent of the invasive S. suis diseases investigated in this study were caused by only two of these genotypes, namely cps2/mrp+/epf+/sly+ and cps9/mrp(*)/epf-/sly+. Thus, this study demonstrates for the first time a uniform profile of the particular virulence-associated genes for the vast majority of the investigated invasive cps9 strains.
Bruin, J P; Kostrzewa, M; van der Ende, A; Badoux, P; Jansen, R; Boers, S A; Diederen, B M W
Generally accepted laboratory methods that have been used for decades do not reliably distinguish between H. influenzae and H. haemolyticus isolates. H. haemolyticus strains are often incorrectly identified as nontypeable Haemophilus influenzae (NTHi). To distinguish H. influenzae from H. haemolyticus we have created a new database on the matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) bio-typer 2 and compared the results with routine determination of Haemophilus (growth requirement for X and V factor), and multilocus sequence typing (MLST). In total we have tested 277 isolates, 244 H. influenzae and 33 H. haemolyticus. Using MLST as the gold standard, the agreement of MALDI-TOF MS was 99.6 %. MALDI-TOF MS allows reliable and rapid discrimination between H. influenzae and H. haemolyticus.
Angen, Øystein; Andreasen, M.; Nielsen, E.O.
The effect of a single or double dose of tulathromycin was evaluated in pigs carrying Actinobacillus pleuropneumoniae serotype 2 in their tonsils. Twenty-nine pigs from a reinfected specific pathogen-free-herd were selected from animals testing positive in an A pleuropneumoniae serotype 2-specific...
Tobias, T.J.; Bouma, A.; Klinkenberg, D.; Daemen, A.J.J.M.; Stegeman, J.A.; Wagenaar, J.A.; Duim, B.
A real-time quantitative PCR (qPCR) for detection of the apxIVA gene of Actinobacillus pleuropneumoniae was validated using pure cultures of A. pleuropneumoniae and tonsillar and nasal swabs from experimentally inoculated Caesarean-derived/colostrum-deprived piglets and naturally infected
Klausen, Joan; Andresen, Lars Ole; Barfod, Kristen
A blocking enzyme-linked immunosorbent assay (ELISA) detecting antibodies against Actinobacillus pleuropneumoniae (Ap) serotype 6 was developed. The blocking ELISA was based on the inhibition of a polyclonal antibody raised against Ap serotype 6. Purified lipopolysaccharide from Ap serotype 6...
Tobias, T.J.; Bouma, A.; Klinkenberg, D.; Daemen, A.J.J.M.; Stegeman, J.A.; Wagenaar, J.A.; Duim, B.
A real-time quantitative PCR (qPCR) for detection of the apxIVA gene of Actinobacillus pleuropneumoniae was validated using pure cultures of A. pleuropneumoniae and tonsillar and nasal swabs from experimentally inoculated Caesarean-derived/colostrum-deprived piglets and naturally infected convention
Vigre, Håkan; Angen, Øystein; Barfod, K.
The objectives of this study were to elucidate at which age tonsillar colonisation by Actinobacillus pleuropneumoniae occurs in pigs and relate this occurrence to the presence of colostral antibodies to A. pleuropneumoniae. The infection patterns were studied in an isolated cohort of pigs, which...
Soares, Taíssa Cook Siqueira; Paes, Antonio Carlos
Streptococcus suis é mundialmente considerado um dos patógenos de maior impacto sanitário e econômico na indústria suinícola. Dentre os sorotipos descritos como zoonóticos, o sorotipoÂ 2 é o mais frequentemente isolado de animais e humanos doentes na maioria dos países. O estudo da epidemiologia das infecções por S.Â suis no Brasil é importante para a implantação de medidas efetivas de controle. O objetivo do presente trabalho foi realizar uma revisão crítica da literatura brasileira, com sup...
Petersen, Heidi Huus; Andreasen, Annette; Kringel, Helene
The aim of the present study was to investigate the population dynamics and potential interactions between Trichuris suis and Oesophagostomum dentatum in experimentally co-infected pigs, by quantification of parasite parameters such as egg excretion, worm recovery and worm location. Forty...... that O. dentatum was located more posteriorly in the gut. The changes in the Trichuris population were less prominent, but faecal egg counts, worm counts 5 wpi (57% recovered vs. 39%) and the proportion of infected animals at 10 wpi were higher in group OT compared to group T. The location of T. suis...
Nghia, Ho Dang Trung; Ho, Dang Trung Nghia; Tu, Le Thi Phuong; Le, Thi Phuong Tu; Wolbers, Marcel; Thai, Cao Quang; Cao, Quang Thai; Hoang, Nguyen Van Minh; Nguyen, Van Minh Hoang; Nga, Tran Vu Thieu; Tran, Vu Thieu Nga; Thao, Le Thi Phuong; Le, Thi Phuong Thao; Phu, Nguyen Hoan; Nguyen, Hoan Phu; Chau, Tran Thi Hong; Tran, Thi Hong Chau; Sinh, Dinh Xuan; Dinh, Xuan Sinh; Diep, To Song; To, Song Diep; Hang, Hoang Thi Thanh; Hoang, Thi Thanh Hang; Truong, Hoang; Campbell, James; Chau, Nguyen Van Vinh; Nguyen, Van Vinh Chau; Chinh, Nguyen Tran; Nguyen, Tran Chinh; Dung, Nguyen Van; Nguyen, Van Dung; Hoa, Ngo Thi; Ngo, Thi Hoa; Spratt, Brian G; Hien, Tran Tinh; Tran, Tinh Hien; Farrar, Jeremy; Schultsz, Constance
Streptococcus suis infection, an emerging zoonosis, is an increasing public health problem across South East Asia and the most common cause of acute bacterial meningitis in adults in Vietnam. Little is known of the risk factors underlying the disease. A case-control study with appropriate hospital and matched community controls for each patient was conducted between May 2006 and June 2009. Potential risk factors were assessed using a standardized questionnaire and investigation of throat and rectal S. suis carriage in cases, controls and their pigs, using real-time PCR and culture of swab samples. We recruited 101 cases of S. suis meningitis, 303 hospital controls and 300 community controls. By multivariate analysis, risk factors identified for S. suis infection as compared to either control group included eating "high risk" dishes, including such dishes as undercooked pig blood and pig intestine (OR(1) = 2.22; 95%CI = [1.15-4.28] and OR(2) = 4.44; 95%CI = [2.15-9.15]), occupations related to pigs (OR(1) = 3.84; 95%CI = [1.32-11.11] and OR(2) = 5.52; 95%CI = [1.49-20.39]), and exposures to pigs or pork in the presence of skin injuries (OR(1) = 7.48; 95%CI = [1.97-28.44] and OR(2) = 15.96; 95%CI = [2.97-85.72]). S. suis specific DNA was detected in rectal and throat swabs of 6 patients and was cultured from 2 rectal samples, but was not detected in such samples of 1522 healthy individuals or patients without S. suis infection. This case control study, the largest prospective epidemiological assessment of this disease, has identified the most important risk factors associated with S. suis bacterial meningitis to be eating 'high risk' dishes popular in parts of Asia, occupational exposure to pigs and pig products, and preparation of pork in the presence of skin lesions. These risk factors can be addressed in public health campaigns aimed at preventing S. suis infection.
Díaz Aparicio, E
Brucellosis is a disease that causes severe economic losses for livestock farms worldwide. Brucella melitensis, B. abortus and B. suis, which are transmitted between animals both vertically and horizontally, cause abortion and infertility in their primary natural hosts - goats and sheep (B. melitensis), cows (B. abortus) and sows (B. suis). Brucella spp. infect not only their preferred hosts but also other domestic and wild animal species, which in turn can act as reservoirs of the disease for other animal species and humans. Brucellosis is therefore considered to be a major zoonosis transmitted by direct contact with animals and/or their secretions, or by consuming milk and dairy products.
Zaccaria, Edoardo; Wels, Michiel; van Baarlen, Peter; Wells, Jerry M.
In S. suis the ComX-inducing peptide (XIP) pheromone regulates ComR-dependent transcriptional activation of comX (or sigX) the regulator of the late competence regulon. The aims of this study were to identify the ComR-regulated genes and in S. suis using genome-wide transcriptomics and identify their function based on orthology and the construction of specific knockout mutants. The ComX regulon we identified, includes all homologs of the “transformasome” a type 4-like pilus DNA binding and transport apparatus identified in Streptococcus pneumoniae, Streptococcus mutans, and Streptococcus thermophilus. A conserved CIN-box (YTACGAAYW), predicted to be bound by ComX, was found in the promoters of operons encoding genes involved in expression of the transformasome. Mutants lacking the major pilin gene comYC were not transformable demonstrating that the DNA uptake pilus is indeed required for competence development in S. suis. Competence was a transient state with the comX regulon shut down after ~15 min even when transcription of comX had not returned to basal levels, indicating other mechanisms control the exit from competence. The ComX regulon also included genes involved in DNA repair including cinA which we showed to be required for high efficiency transformation. In contrast to S. pneumoniae and S. mutans the ComX regulon of S. suis did not include endA which converts the transforming DNA into ssDNA, or ssbA, which protects the transforming ssDNA from degradation. EndA appeared to be essential in S. suis so we could not generate mutants and confirm its role in DNA transformation. Finally, we identified a putative homolog of fratricin, and a putative bacteriocin gene cluster, that were also part of the CIN-box regulon and thus may play a role in DNA release from non-competent cells, enabling gene transfer between S. suis pherotypes or S. suis and other species. S. suis mutants of oppA, the binding subunit of the general oligopeptide transporter were not
Rasmussen, S. R.; Aarestrup, Frank Møller; Jensen, N. E.
A total of 122 Streptococcus suis serotype 2 strains were characterized thoroughly by comparing clinical and pathological observations, ribotype profiles, and antimicrobial resistance. Twenty-one different ribotype profiles were found and compared by cluster analysis, resulting in the identificat......A total of 122 Streptococcus suis serotype 2 strains were characterized thoroughly by comparing clinical and pathological observations, ribotype profiles, and antimicrobial resistance. Twenty-one different ribotype profiles were found and compared by cluster analysis, resulting...... of resistance to antibiotics because strains isolated from pigs with meningitis were resistant to sulfamethazoxazole and strains isolated from pigs with pneumonia, endocarditis, pericarditis, or septicemia were resist-ant to tetracycline....
Brenner, D J; Mayer, L W; Carlone, G M; Harrison, L. H.; Bibb, W F; Brandileone, M. C.; Sottnek, F O; K. Irino; Reeves, M W; Swenson, J M
Brazilian purpuric fever (BPF) is a recently recognized fulminant pediatric disease characterized by fever, with rapid progression to purpura, hypotensive shock, and death. BPF is usually preceded by purulent conjunctivitis that has resolved before the onset of fever. Both the conjunctivitis and BPF are caused by Haemophilus influenzae biogroup aegyptius (formerly called H. aegyptius). Isolates from 15 BPF cases, mainly from blood or hemorrhagic cerebrospinal fluid, case-associated isolates f...
An agar disc diffusion method was used to examine the sensitivity of 27 Haemophilus paragallinarum (Hpg) isolates consisted of 23 local isolates, 4 standard isolates (serotype A) and Escherichia coli ATCC 24922 as a control to eight antimicrobial drugs (ampicillin, erythromycin, oxytetracycline, doxycycline, neomycin, streptomycin, colistine and sulphanlethoxazole-trimethoprim) . Twenty one out of 23 local isolates of Hpg were sensitive to doxycycline, 19 isolates to ampsllin, 18 isolates to ...
Full Text Available Haemophilus influenzae is a Gram-negative bacillus commonly known to cause upper respiratory tract infections. Skin and soft tissue infections are very uncommon. Of these, the majority were associated with necrotizing fasciitis requiring emergent debridement. We report a case of pyomyositis caused by Haemophilus influenzae in an adult with diabetes.
Akpavie, S O; Ajuwape, A T; Ikheloa, J O
An outbreak of Haemophilus aegyptius infection in a livestock farm located in Maya, Oyo State, Nigeria is reported. Diagnosis was based on clinical signs of central nervous system disturbance, histopathological findings of meningoencephalomyelitis, acute multifocal necrotising purulent hepatitis and the isolation of Haemophilus aegyptius from the spinal cord. Other diseases that can cause nervous disturbance are discussed.
Boukadida, Jalel; Hannachi, Neila
We bring back an adult case of purulent meningitis to Haemophilus influenzae. We insist on the particular aspects of the host of this meningitis type at the adult. These aspects must be searched every time that Haemophilus influenzae is isolated in cerebrospinal fluid in adult's meningitis.
Sandstedt, Sara A.; Zhang, Lixin; Patel, Mayurika; McCrea, Kirk W.; Qin, Zhaohui; Marrs, Carl F.; Gilsdorf, Janet R.
Summary New methods to distinguish between nontypeable Haemophilus influenzae and nonhemolytic Haemophilus haemolyticus were compared. The results of iga variable region hybridization to dotblots and library-on-a-slide microarrays were more similar to a “gold standard” multigene phylogenetic tree than iga conserved region hybridization or P6 7F3 epitope immunoblots. PMID:18652852
George, Gemlyn; Climaco, Antoinette
Haemophilus influenzae is a Gram-negative bacillus commonly known to cause upper respiratory tract infections. Skin and soft tissue infections are very uncommon. Of these, the majority were associated with necrotizing fasciitis requiring emergent debridement. We report a case of pyomyositis caused by Haemophilus influenzae in an adult with diabetes. PMID:28352482
Chien, Maw-Sheng; Chan, You-Yu; Chen, Zeng-Weng; Wu, Chi-Ming; Liao, Jiunn-Wang; Chen, Ter-Hsin; Lee, Wei-Cheng; Yeh, Kuang-Sheng; Hsuan, Shih-Ling
Actinobacillus pleuropneumoniae (AP) is the causative agent of swine pleuropneumonia, a fibrinous, exudative, hemorrhagic, necrotizing pleuropneumonia affecting all ages of pigs. Actinobacillus pleuropneumoniae exotoxins (Apx) are one of the major virulence factors of AP. Due to the complex nature of Apx toxins produced by AP, little is known regarding the interactions of individual species of Apx toxin with target cells. The objective of this study was to examine whether AP serotype 10-derived exotoxin, ApxI, caused apoptosis in porcine alveolar macrophages (PAMs) and to delineate the underlying signaling pathways. Isolated PAMs were stimulated with different concentrations of native ApxI and monitored for apoptosis using Hoechst staining, TUNEL, and DNA laddering assays. The ApxI-stimulated PAMs exhibited typical morphological features of apoptosis, including condensation of chromatin, formation of apoptotic bodies and DNA laddering. ApxI-induced apoptosis in a concentration- and time-dependent manner. Furthermore, to delineate the signaling events involved in ApxI-induced apoptosis, it was observed that caspase 3 was activated in ApxI-stimulated PAMs. Ablation of caspase 3 activity via specific inhibitors protected PAMs from apoptosis by ApxI. This study is the first to demonstrate that native ApxI causes apoptosis in PAMs at low concentrations and that these apoptotic events are mediated via a caspase 3-dependent pathway. These findings suggest a role of ApxI in AP infection as it might impair the host defense system through the induction of apoptosis in PAMs.
Gutiérrez-Martín, César B; del Blanco, Noemí García; Blanco, Mónica; Navas, Jesús; Rodríguez-Ferri, Elías F
A total of 229 Spanish Actinobacillus pleuropneumoniae isolates recovered from diseased pigs with pleuropneumonia from 1997 to 2004 was tested for their susceptibility to 11 antimicrobials in a broth microdilution method. All the isolates were susceptible to florfenicol and most of them to cephalothin; however, a high rate of resistance was observed to tetracycline. A bimodal or multimodal distribution of isolates over the MIC range were observed for penicillins, tetracycline, trimethoprim, sulfisoxazole and nalidixic acid, suggesting the development of acquired resistance. Eight resistance patterns were established, and 21.1% of the isolates were resistant to at least two antimicrobials. In addition, a considerable increase in the resistance to tetracyclines was observed during the last decade in Spain, when compared with other A. pleuropneumoniae strains isolated during 1987-1988 (Gutiérrez, C.B., Píriz, S., Vadillo, S., Rodríguez Ferri, E.F., 1993. In vitro susceptibility of Actinobacillus pleuropneumoniae strains to 42 antimicrobial agents. Am. J. Vet. Res. 54, 546-550); this finding was also observed for gentamicin in minor percentage.
Pasma, Satriani Aga; Daik, Rusli; Maskat, Mohamad Yusof
Succinic acid is a common metabolite in plants, animals and microorganisms. It has been used widely in agricultural, food and pharmaceutical industries. Enzymatic hydrolysate glucose from oil palm empty fruit bunch (OPEFB) cellulose was used as a substrate for succinic acid production using Actinobacillus succinogenes. Using cellulose extraction from OPEFB can enhance the production of glucose as a main substrate for succinic acid production. The highest concentration of glucose produced from enzymatic hydrolysis is 167 mg/mL and the sugar recovery is 0.73 g/g of OPEFB. By optimizing the culture medium for succinic acid fermentation with enzymatic hydrolysate of OPEFB cellulose, the nitrogen sources could be reduced to just only 2.5 g yeast extract and 2.5 g corn step liquor. Batch fermentation was carried out using enzymatic hydrolysate of OPEFB cellulose with yeast extract, corn steep liquor and the salts mixture, 23.5 g/L succinic acid was obtained with consumption of 72 g/L glucose in enzymatic hydrolysate of OPEFB cellulose at 38 hours and 37°C. This study suggests that enzymatic hydrolysate of OPEFB cellulose maybe an alternative substrate for the efficient production of succinic acid by Actinobacillus succinogenes.
Full Text Available Problem statement: Plant variety protection relates to intellectual property rights over plant varieties which guarantee rights-holders exclusive commercial rights for a specific period of time. Article 27 (3(b of the TRIPS Agreement, compulsorily mandates that every member-state of the WTO must introduce such protection through domestic legislation by certain set time frames. These rights are one form of IPR being aggressively imposed on developing countries and are often touted as a 'soft' patent regime. Plant variety laws are just as threatening as industrial patents on biodiversity and also represent an attack on the rights of farming an other communities at the local level. From a legal perspective, the protection of plant varieties in India remains an issue which is far from settled even though the Protection of Plant Varieties and Farmers' Rights Act was adopted in 2001 in compliance with the TRIPS Agreement. This study argued that the goal of the IP regime should be to balance the competing needs of maximizing societal innovation while appropriately rewarding the individuals that contribute to that innovation. Towards this end, the study seeks to analyze the issues related to the protection of plant varieties with reference to the TRIPS agreement along with the biodiversity treaty and the PGRFA Treaty. One of the chief distinguishing features of the PGRFA Treaty is its emphasis on farmers' rights. This characteristic is analyzed further in the Indian context. Conclusion: Plant variety protection is linked to both agricultural innovation and the conservation of biological resources, although on different levels. The present international legal framework remains partly inconclusive with regard to they type of agricultural management that it seeks to encourage. Though the development of sui generis programs for plant variety protection is still in a nascent stage, this paper analyses the advantages and disadvantages of the Farmers' Rights
Ye, Huiyan; Cai, Mingzhu; Zhang, Huimin; Li, Zhencui; Wen, Ronghui; Feng, Youjun
Biotin protein ligase is universal in three domains of life. The paradigm version of BPL is the Escherichia coli BirA that is also a repressor for the biotin biosynthesis pathway. Streptococcus suis, a leading bacterial agent for swine diseases, seems to be an increasingly-important opportunistic human pathogen. Unlike the scenario in E. coli, S. suis lacks the de novo biotin biosynthesis pathway. In contrast, it retains a bioY, a biotin transporter-encoding gene, indicating an alternative survival strategy for S. suis to scavenge biotin from its inhabiting niche. Here we report functional definition of S. suis birA homologue. The in vivo functions of the birA paralogue with only 23.6% identity to the counterpart of E. coli, was judged by its ability to complement the conditional lethal mutants of E. coli birA. The recombinant BirA protein of S. suis was overexpressed in E. coli, purified to homogeneity and verified with MS. Both cellulose TLC and MALDI-TOFF-MS assays demonstrated that the S. suis BirA protein catalyzed the biotinylation reaction of its acceptor biotin carboxyl carrier protein. EMSA assays confirmed binding of the bioY gene to the S. suis BirA. The data defined the first example of the bifunctional BirA ligase/repressor in Streptococcus.
Hansen, Christine Soholm; Hasseldam, Henrik; Bacher, Idahella Hyldgaard
of excretory/secretory products before disease onset, resulted in a significant decrease in disease severity as well as markedly reduced TH1 and TH17 T-cell responses, centrally in the spinal cord as well as in the periphery, i.e. the spleen. Thus, parenteral administration of T. suis-derived products results...
Full Text Available Streptococcus suis serotype 2 is an important zoonotic pathogen causing severe infections in pigs and humans. The pathogenesis of S. suis 2 infections, however, is still poorly understood. Spx proteins are a group of global regulators involved in stress tolerance and virulence. In this study, we characterized two orthologs of the Spx regulator, SpxA1 and SpxA2 in S. suis 2. Two mutant strains (ΔspxA1 and ΔspxA2 lacking the spx genes were constructed. The ΔspxA1 and ΔspxA2 mutants displayed different phenotypes. ΔspxA1 exhibited impaired growth in the presence of hydrogen peroxide, while ΔspxA2 exhibited impaired growth in the presence of SDS and NaCl. Both mutants were defective in medium lacking newborn bovine serum. Using a murine infection model, we demonstrated that the abilities of the mutant strains to colonize the tissues were significantly reduced compared to that of the wild-type strain. The mutant strains also showed a decreased level of survival in pig blood. Microarray analysis revealed a global regulatory role for SpxA1 and SpxA2. Furthermore, we demonstrated for the first time that Spx is involved in triggering the host inflammatory response. Collectively, our data suggest that SpxA1 and SpxA2 are global regulators that are implicated in stress tolerance and virulence in S. suis 2.
Wisselink, Hendrikus Jan
Streptococcus suis is an important pig pathogen which is mainly associated with meningitis, arthritis and septicaemia. Control of the disease is hampered by the lack of effective vaccines and the lack of reliable diagnostic tests with high specificity and sensitivity. The development of these tools
Zaccaria, Edoardo; Cao, Rui; Wells, Jerry M.; Baarlen, Van Peter
Streptococcus suis is an encapsulated Gram-positive bacterium, and the leading cause of sepsis and meningitis in young pigs resulting in considerable economic losses in the porcine industry. It is also considered an emerging zoonotic agent. In the environment, both avirulent and virulent strains
@@ In treating Meniere's disease, author has found that the compatible use of heavy dosage of Gu Sui Bu (骨碎补 Rhizoma Drynariae) can produce very good effect for relieving dizziness, vertigo and tinnitus. Some of the sample cases are cited in the following.
Zaccaria, E.; Baarlen, van P.; Greeff, de A.; Morrison, D.A.; Smith, H.; Wells, J.M.
Here we show that S. suis, a major bacterial pathogen of pigs and emerging pathogen in humans responds to a peptide pheromone by developing competence for DNA transformation. This species does not fall within any of the phylogenetic clusters of streptococci previously shown to regulate competence vi
Dake Zhang; Nan Du; Sufang Ma; Qingtao Hu; Guangwen Lu; Wei Chen; Changqing Zeng
The Streptococcus suis serotype 2 (S. suis 2) isolates 05ZYH33 and 98HAH33 have caused severe human infections in China. Using a strand-specific RNA-seq analysis, we compared the in vitro transcriptomes of these two Chinese isolates with that of a reference strain (P1/7). In the 89K genomic island that is specific to these Chinese isolates, a toxin–antitoxin system showed relatively high levels of transcription among the S. suis. The known virulence factors with high transcriptional activity in these two highly-pathogenic strains are mainly involved in adhesion, biofilm formation, hemolysis and the synthesis and transport of the outer membrane protein. Furthermore, our analysis of novel transcripts identified over 50 protein-coding genes with one of them encoding a toxin protein. We also predicted over 30 small RNAs (sRNAs) in each strain, and most of them are involved in riboswitches. We found that six sRNA candidates that are related to bacterial virulence, including cspA and rli38, are specific to Chinese isolates. These results provide insight into the factors responsible for the difference in virulence among the different S. suis 2 isolates.
The objective of the current study was to evaluate the safety, immunogenicity and clearance of the natural rough mutant of Brucella suis strain 353-1 (353-1) as a vaccine in domestic swine. In three studies encompassing 155 animals, pigs were inoculated with 353-1 by conjunctival (5 x 10**7 CFU), p...
Brucella suis strain 353-1 is a stable vaccine strain that is clinically safe, does not cause positive serologic responses on conventional brucellosis surveillance tests, and induces humoral and cellular immunity in swine after vaccination. In this study, we evaluated tissue clearance and immunologi...
Dang, T.N.H.; Thi, P.T.L.; Wolbers, M.; Quang, T.C.; van, M.H.N.; Vu, T.N.T.; Hoan, P.N.; Thi, H.C.T.; Xuan, S.D.; Song, D.T.; Thi, T.H.H.; Truong, H.; Campbell, J.; van, V.C.N.; Tran, C.N.; van, D.N.; Thi, H.N.; Spratt, B.G.; Tinh, H.T.; Farrar, J.; Schultsz, C.
Background: Streptococcus suis infection, an emerging zoonosis, is an increasing public health problem across South East Asia and the most common cause of acute bacterial meningitis in adults in Vietnam. Little is known of the risk factors underlying the disease. Methods and Findings: A case-control
Full Text Available Streptococcus suis, a major porcine pathogen, has been receiving growing attention not only for its role in severe and increasingly reported infections in humans, but also for its involvement in drug resistance. Recent studies and the analysis of sequenced genomes have been providing important insights into the S. suis resistome, and have resulted in the identification of resistance determinants for tetracyclines, macrolides, aminoglycosides, chloramphenicol, antifolate drugs, streptothricin, and cadmium salts. Resistance gene-carrying genetic elements described so far include integrative and conjugative elements, transposons, genomic islands, phages, and chimeric elements. Some of these elements are similar to those reported in major streptococcal pathogens such as Streptococcus pyogenes, Streptococcus pneumoniae, and Streptococcus agalactiae and share the same chromosomal insertion sites. The available information strongly suggests that S. suis is an important antibiotic resistance reservoir that can contribute to the spread of resistance genes to the above-mentioned streptococci. S. suis is thus a paradigmatic example of possible intersections between animal and human resistomes.
Takeuchi, Dan; Kerdsin, Anusak; Akeda, Yukihiro; Chiranairadul, Piphat; Loetthong, Phacharaphan; Tanburawong, Nutchada; Areeratana, Prasanee; Puangmali, Panarat; Khamisara, Kasean; Pinyo, Wirasinee; Anukul, Rapeepun; Samerchea, Sutit; Lekhalula, Punpong; Nakayama, Tatsuya; Yamamoto, Kouji; Hirose, Masayo; Hamada, Shigeyuki; Dejsirilert, Surang; Oishi, Kazunori
AbstractStreptococcus suis is an important zoonotic pathogen in swine and humans that causes sepsis and meningitis. Our previous study in Thailand showed that the prevalence of S. suis infection in humans, especially in northern areas of Thailand, and the transmission of the pathogen occurred mainly through the consumption of traditional raw pork products. Considering the high incidence proportion and mortality rate of the disease as an important public health problem, we implemented a food safety campaign in the Phayao Province in northern Thailand in 2011. We evaluated the effects of a food safety campaign by comparing the sociodemographic, clinical, and bacteriological characteristics of cases before and after the campaign. The follow-up study showed a marked decrease of the incidence proportion in the first 2 years, indicating the effectiveness of the campaign. In the third year, however, the incidence proportion slightly increased again, indicating the existence of deep-rooted cultural behaviors and the necessity of continuous public health intervention. Furthermore, epidemiological analysis of the cases made it possible to estimate the infectivity of the pathogen via the oral route of infection. In the present study, we showed the effectiveness of the food safety campaign for controlling the S. suis infection, and we present a role model public health intervention for prevalent areas affected by S. suis infection in humans.
Streptococcus suis is a swine pathogen responsible for economic losses to the pig industry worldwide. Additionally, it is a zoonotic agent that can cause severe infections in those in close contact with infected pigs and/or who consume uncooked or undercooked pork products. Here, we report nine draf...
Full Text Available Este estudio se propuso estimar la distribución de la infección por Mycoplasma suis en poblaciones de cerdos de Argentina e identificar factores de riesgo asociados. Se recolectaron 284 muestras de sangre de cerdos de diferentes categorías productivas en frigoríficos y granjas de las provincias de Santa Fe, Córdoba y Buenos Aires. Amplificando el gen del ARNr 16S de M. suis a través de la reacción en cadena de la polimerasa (PCR, se calculó un porcentaje de infectados del 64%. Se estimó además que no existía asociación estadísticamente significativa (p>0,1 entre un resultado positivo a la PCR y el sexo del animal muestreado, los antecedentes de anemia en la granja y las condiciones de alojamiento. Contrariamente se encontró asociación significativa (pThe objective of this study was to estimate the distribution of Mycoplasma suis infection in pig populations of Argentina and identify associated risk factors. Blood samples were collected from 284 pigs, including different productive categories of animals, in abattoirs and herds from Santa Fe, Córdoba and Buenos Aires provinces. Based on the polymerase chain reaction (PCR amplification of the M. suis 16S rRNA gene, it was estimated a proportion of infected animals of 0.64. Non-statistically significant (P>0.1 associations were found between gender, anemia herd history, and breeding conditions with PCR results. On the other hand, significant associations (P<0.1 were found between sanitary status to the infection and geographic origin and productive categories. It was estimated that pigs from Buenos Aires and Córdoba provinces were at higher risk of being PCR-positive than pigs from Santa Fe, while piglets and post-weaning pigs were at lower risk of being PCR-positive than other categories. This study suggests that M. suis infection is widespread in the studied pig populations of Argentina.
Hansen, Tina V. A.; Nejsum, Peter; Friis, Christian; Olsen, Annette; Thamsborg, Stig Milan
Background The single-dose benzimidazoles used against Trichuris trichiura infections in humans are not satisfactory. Likewise, the benzimidazole, fenbendazole, has varied efficacy against Trichuris suis whereas Oesophagostomum dentatum is highly sensitive to the drug. The reasons for low treatment efficacy of Trichuris spp. infections are not known. Methodology We studied the effect of fenbendazole, albendazole and levamisole on the motility of T. suis and O. dentatum and measured concentrations of the parent drug compounds and metabolites of the benzimidazoles within worms in vitro. The motility and concentrations of drug compounds within worms were compared between species and the maximum specific binding capacity (Bmax) of T. suis and O. dentatum towards the benzimidazoles was estimated. Comparisons of drug uptake in living and killed worms were made for both species. Principal findings The motility of T. suis was generally less decreased than the motility of O. dentatum when incubated in benzimidazoles, but was more decreased when incubated in levamisole. The Bmax were significantly lower for T. suis (106.6, and 612.7 pmol/mg dry worm tissue) than O. dentatum (395.2, 958.1 pmol/mg dry worm tissue) when incubated for 72 hours in fenbendazole and albendazole respectively. The total drug concentrations (pmol/mg dry worm tissue) were significantly lower within T. suis than O. dentatum whether killed or alive when incubated in all tested drugs (except in living worms exposed to fenbendazole). Relatively high proportions of the anthelmintic inactive metabolite fenbendazole sulphone was measured within T. suis (6–17.2%) as compared to O. dentatum (0.8–0.9%). Conclusion/Significance The general lower sensitivity of T. suis towards BZs in vitro seems to be related to a lower drug uptake. Furthermore, the relatively high occurrence of fenbendazole sulphone suggests a higher detoxifying capacity of T. suis as compared to O. dentatum. PMID:24699263
Tina V A Hansen
Full Text Available BACKGROUND: The single-dose benzimidazoles used against Trichuris trichiura infections in humans are not satisfactory. Likewise, the benzimidazole, fenbendazole, has varied efficacy against Trichuris suis whereas Oesophagostomum dentatum is highly sensitive to the drug. The reasons for low treatment efficacy of Trichuris spp. infections are not known. METHODOLOGY: We studied the effect of fenbendazole, albendazole and levamisole on the motility of T. suis and O. dentatum and measured concentrations of the parent drug compounds and metabolites of the benzimidazoles within worms in vitro. The motility and concentrations of drug compounds within worms were compared between species and the maximum specific binding capacity (Bmax of T. suis and O. dentatum towards the benzimidazoles was estimated. Comparisons of drug uptake in living and killed worms were made for both species. PRINCIPAL FINDINGS: The motility of T. suis was generally less decreased than the motility of O. dentatum when incubated in benzimidazoles, but was more decreased when incubated in levamisole. The Bmax were significantly lower for T. suis (106.6, and 612.7 pmol/mg dry worm tissue than O. dentatum (395.2, 958.1 pmol/mg dry worm tissue when incubated for 72 hours in fenbendazole and albendazole respectively. The total drug concentrations (pmol/mg dry worm tissue were significantly lower within T. suis than O. dentatum whether killed or alive when incubated in all tested drugs (except in living worms exposed to fenbendazole. Relatively high proportions of the anthelmintic inactive metabolite fenbendazole sulphone was measured within T. suis (6-17.2% as compared to O. dentatum (0.8-0.9%. CONCLUSION/SIGNIFICANCE: The general lower sensitivity of T. suis towards BZs in vitro seems to be related to a lower drug uptake. Furthermore, the relatively high occurrence of fenbendazole sulphone suggests a higher detoxifying capacity of T. suis as compared to O. dentatum.
Ana M S Guimaraes
Full Text Available Mycoplasma suis, the causative agent of porcine infectious anemia, has never been cultured in vitro and mechanisms by which it causes disease are poorly understood. Thus, the objective herein was to use whole genome sequencing and analysis of M. suis to define pathogenicity mechanisms and biochemical pathways. M. suis was harvested from the blood of an experimentally infected pig. Following DNA extraction and construction of a paired end library, whole-genome sequencing was performed using GS-FLX (454 and Titanium chemistry. Reads on paired-end constructs were assembled using GS De Novo Assembler and gaps closed by primer walking; assembly was validated by PFGE. Glimmer and Manatee Annotation Engine were used to predict and annotate protein-coding sequences (CDS. The M. suis genome consists of a single, 742,431 bp chromosome with low G+C content of 31.1%. A total of 844 CDS, 3 single copies, unlinked rRNA genes and 32 tRNAs were identified. Gene homologies and GC skew graph show that M. suis has a typical Mollicutes oriC. The predicted metabolic pathway is concise, showing evidence of adaptation to blood environment. M. suis is a glycolytic species, obtaining energy through sugars fermentation and ATP-synthase. The pentose-phosphate pathway, metabolism of cofactors and vitamins, pyruvate dehydrogenase and NAD(+ kinase are missing. Thus, ribose, NADH, NADPH and coenzyme A are possibly essential for its growth. M. suis can generate purines from hypoxanthine, which is secreted by RBCs, and cytidine nucleotides from uracil. Toxins orthologs were not identified. We suggest that M. suis may cause disease by scavenging and competing for host' nutrients, leading to decreased life-span of RBCs. In summary, genome analysis shows that M. suis is dependent on host cell metabolism and this characteristic is likely to be linked to its pathogenicity. The prediction of essential nutrients will aid the development of in vitro cultivation systems.
Seele, Jana; Nau, Roland; Prajeeth, Chittappen K; Stangel, Martin; Valentin-Weigand, Peter; Seitz, Maren
Streptococcus (S.) suis infections are the most common cause of meningitis in pigs. Moreover, S. suis is a zoonotic pathogen, which can lead to meningitis in humans, mainly in adults. We assume that glial cells may play a crucial role in host-pathogen interactions during S. suis infection of the central nervous system. Glial cells are considered to possess important functions during inflammation and injury of the brain in bacterial meningitis. In the present study, we established primary astrocyte-microglial cell co-cultures to investigate interactions of S. suis with glial cells. For this purpose, microglial cells and astrocytes were isolated from new-born mouse brains and characterized by flow cytometry, followed by the establishment of astrocyte and microglial cell mono-cultures as well as astrocyte-microglial cell co-cultures. In addition, we prepared microglial cell mono-cultures co-incubated with uninfected astrocyte mono-culture supernatants and astrocyte mono-cultures co-incubated with uninfected microglial cell mono-culture supernatants. After infection of the different cell cultures with S. suis, bacteria-cell association was mainly observed with microglial cells and most prominently with a non-encapsulated mutant of S. suis. A time-dependent induction of NO release was found only in the co-cultures and after co-incubation of microglial cells with uninfected supernatants of astrocyte mono-cultures mainly after infection with the capsular mutant. Only moderate cytotoxic effects were found in co-cultured glial cells after infection with S. suis. Taken together, astrocytes and astrocyte supernatants increased interaction of microglial cells with S. suis. Astrocyte-microglial cell co-cultures are suitable to study S. suis infections and bacteria-cell association as well as NO release by microglial cells was enhanced in the presence of astrocytes.
Gruening, Petra; Fulde, Marcus; Valentin-Weigand, Peter; Goethe, Ralph
Streptococcus suis is an important cause of infectious diseases in young pigs. Little is known about the virulence factors or protective antigens of S. suis. Recently, we have identified two proteins of the arginine deiminase system (ADS) of S. suis, which were temperature induced and expressed on the streptococcal surface (N. Winterhoff, R. Goethe, P. Gruening, M. Rohde, H. Kalisz, H. E. Smith, and P. Valentin-Weigand, J. Bacteriol. 184:6768-6776, 2002). In the present study, we analyzed the complete ADS of S. suis. Due to their homologies to the recently published S. gordonii ADS genes, the genes for arginine deiminase, ornithine carbamoyl-transferase, and carbamate kinase, which were previously designated adiS, octS, and ckS, respectively, were renamed arcA, arcB, and arcC, respectively. Our data revealed that arcA, arcB, and arcC of the S. suis ADS are transcribed from an operon (arcABC operon). Additionally, putative ADS-associated genes were cloned and sequenced which, however, did not belong to the arcABC operon. These were the flpS gene upstream of the arcABC operon with homology to the flp transcription regulator of S. gordonii and the arcD, arcT, arcH, and argR genes downstream of the arcABC operon with high homologies to a putative arginine-ornithine antiporter, a putative dipeptidase of S. gordonii, a putative beta-N-acetylhexosaminidase of S. pneumoniae, and a putative arginine repressor of S. gordonii, respectively. The transcriptional start point of the arcABC operon was determined, and promoter analysis provided evidence that multiple factors contribute to the regulation of the ADS. Thus, a putative binding site for a transcription regulator of the Crp/Fnr family, an ArgR-binding site, and two cis-acting catabolite response elements were identified in the promoter-operator region of the operon. Consistent with this, we could demonstrate that the ADS of S. suis is inducible by arginine and reduced O2 tension and subject to carbon catabolite
Danilo Carloto Gomes
Full Text Available Neste trabalho, são descritos dois casos fatais de septicemia com lesões embólicas causadas por Actinobacillus equuli subsp. haemolyticus em potros recém-nascidos. Em um dos animais, foram observados, na necropsia, pequenos nódulos esbranquiçados de aproximadamente 0,2cm de diâmetro na cortical dos rins e no outro havia uma área de coloração acinzentada no lobo diafragmático esquerdo do pulmão. As principais alterações microscópicas observadas no primeiro animal foram rins com infiltrado inflamatório multifocal a coalescente acentuado, com predomínio de neutrófilos, associado com áreas basofílicas levemente granulares compostas por grumos bacterianos. No segundo animal, o pulmão apresentava infiltrado inflamatório neutrofílico, edema, congestão e colônias bacterianas intravasculares. Em ambos os casos, colônias bacterianas foram encontradas disseminadas por vários órgãos incluindo capilares cerebrais. Nos dois casos foi isolado e identificado A. equuli subsp. haemolyticus.This paper describes two fatal cases of embolic and septicaemic lesions caused by Actinobacillus equuli subsp. haemolyticus in two newborn foals. In one foal was observed at necropsy small whitish nodules of approximately 0,2cm in diameter on the renal cortex and the other foal had an area of gray color in the left diaphragmatic lobe of the lung. The main histologic changes were observed in the first foal kidneys with multifocal to coalescing inflammatory suppurative infiltrates associated with slightly granular basophilic bacterial colonies. In the second animal the lung showed neutrophilic inflammatory infiltrate, edema, congestion and presence of intravascular bacterial colonies. In both cases, the bacteria were disseminated by several organs including cerebral capillary cerebral. In both cases A. equuli subsp. haemolyticus was isolated and identified.
Mario Julio AVILA-CAMPOS
Full Text Available Actinobacillus actinomycetemcomitans is implicated as the causative agent of localized juvenile periodontitis. This organism possesses a large number of virulence factors with a wide range of activities and also interfere with tissue repair. Fifty isolates of A. actinomycetemcomitans from 20 periodontal patients were examined to evaluate other putative virulence factors. In this study, the capsule, DNase, coagulase, fibrinolysin, proteolytic, haemolysin and bacteriocin production, haemagglutination, serum sensitivity, epithelial cells attachment, hydrophobicity and virulence of the A. actinomycetemcomitans isolates were evaluated. All the isolates were resistant to the different tested sera. 70% to 94% were alpha-haemolytics and agglutinated all blood types. Most of isolates produced antagonistic substances and they had a low hydrophobicity. None of the isolates was pathogenic for mice. Little is known as to wether these factors may act in the development of periodontal disease, and further studies are required for an application in pathogenic and systematic terms.Actinobacillus actinomycetemcomitans está implicado como o agente etiológico da periodontite juvenil localizada. Este organismo possui inúmeros fatores de virulência que podem interferir no reparo tissular. 50 isolados de A. actinomycetemcomitans de pacientes com periodontite foram examinados para avaliar outros possíveis fatores de virulência. Neste estudo, foi avaliada a produção de cápsula, DNase, coagulase, fibrinolisina, atividade proteolítica, hemolisina e bacteriocina, assim como hemaglutinação, sensibilidade ao soro, aderência às células epiteliais, hidrofobicidade e virulência de A. actinomycetemcomitans. Todos os isolados foram resistentes para todos os tipos de soro utilizados. 70% a 94% dos isolados foram alfa-hemolíticos e aglutinaram todos os tipos sanguíneos. A maioria dos isolados produziu substâncias antagonistas e apresentaram baixa hidrofobicidade
Skallerup, Per; Thamsborg, Stig Milan; Jørgensen, Claus Bøttcher;
Whipworms (Trichuris spp.) infect a variety of hosts, including domestic animals and humans. Of considerable interest is the porcine whipworm, T. suis, which is particularly prevalent in outdoor production systems. High infection levels may cause growth retardation, anaemia and haemorrhagic...... a whole-genome scan of an F1 resource population (n=195) trickle-infected with T. suis. A measured genotype analysis revealed a putative quantitative trait locus (QTL) for T. suis FEC on chromosome 13 covering ∼4.5Mbp, although none of the SNPs reached genome-wide significance. We tested the hypothesis...
Bager, Peter; Kapel, Christian Moliin Outzen; Roepstorff, Allan Knud;
Symptoms after human infection with the helminth Trichuris suis have not previously been described. Exposure to helminths has been suggested as immune therapy against allergy and autoimmune diseases. We randomized adults with allergic rhinitis to ingest a dose of 2500 T. suis eggs or placebo every...... by a fluoroenzymeimmunoassay (Phadia ApS). During 163 days complete follow-up, subjects ingesting T. suis eggs (N = 49) had a three to 19-fold higher rate of events (median duration, 2 days) with gastrointestinal reactions (moderate to severe flatulence, diarrhea, and upper abdominal pain) compared with placebo subjects (N...
Baums, Christoph G; Kaim, Ute; Fulde, Marcus; Ramachandran, Girish; Goethe, Ralph; Valentin-Weigand, Peter
Streptococcus suis serotype 2 is a porcine and human pathogen with adhesive and invasive properties. In other streptococci, large surface-associated proteins (>100 kDa) of the MSCRAMM family (microbial surface components recognizing adhesive matrix molecules) are key players in interactions with host tissue. In this study, we identified a novel opacity factor of S. suis (OFS) with structural homology to members of the MSCRAMM family. The N-terminal region of OFS is homologous to the respective regions of fibronectin-binding protein A (FnBA) of Streptococcus dysgalactiae and the serum opacity factor (SOF) of Streptococcus pyogenes. Similar to these two proteins, the N-terminal domain of OFS opacified horse serum. Serum opacification activity was detectable in sodium dodecyl sulfate extracts of wild-type S. suis but not in extracts of isogenic ofs knockout mutants. Heterologous expression of OFS in Lactococcus lactis demonstrated that a high level of expression of OFS is sufficient to provide surface-associated serum opacification activity. Furthermore, serum opacification could be inhibited by an antiserum against recombinant OFS. The C-terminal repetitive sequence elements of OFS differed significantly from the respective repeat regions of FnBA and SOF as well as from the consensus sequence of the fibronectin-binding repeats of MSCRAMMs. Accordingly, fibronectin binding was not detectable in recombinant OFS. To investigate the putative function of OFS in the pathogenesis of invasive S. suis diseases, piglets were experimentally infected with an isogenic mutant strain in which the ofs gene had been knocked out by an in-frame deletion. The mutant was severely attenuated in virulence but not in colonization, demonstrating that OFS represents a novel virulence determinant of S. suis.
Kreizinger, Zsuzsa; Foster, Jeffrey T; Rónai, Zsuzsanna; Sulyok, Kinga M; Wehmann, Enikő; Jánosi, Szilárd; Gyuranecz, Miklós
Porcine brucellosis generally manifests as disorders in reproductive organs potentially leading to serious losses in the swine industry. Brucella suis biovar 2 is endemic in European wild boar (Sus scrofa) and hare (Lepus europeus, Lepus capensis) populations, thus these species may play a significant role in disease spread and serve as potential sources of infection for domestic pigs. The aim of this study was an epidemiologic analysis of porcine brucellosis in Hungary and a comparative analysis of B. suis bv. 2 strains from Europe using multiple-locus variable-number tandem repeat analysis (MLVA). MLVA-16 and its MLVA-11 subset were used to determine the genotypes of 68 B. suis bv. 2 isolates from Hungary and results were then compared to European MLVA genotypes. The analyses indicated relatively high genetic diversity of B. suis bv. 2 in Hungary. Strains isolated from hares and wild boars from Hungary showed substantial genetic divergence, suggesting separate lineages in each host and no instances of cross species infections. The closest relatives of strains from Hungarian wild boars and domestic pigs were mainly in the isolates from German and Croatian boars and pigs. The assessment of the European MLVA genotypes of wild boar isolates generally showed clustering based on geographic origin. The hare strains were relatively closely related to one another and did not cluster based on geographic origin. The limited relationships between geographic origin and genotype in isolates from hares might be the result of cross-border live animal translocation. The results could also suggest that certain B. suis strains are more adapted to hares. Across Europe, isolates from domestic pigs were closely related to isolates originating from both hares and wild boars, supporting the idea that wild animals are a source of brucellosis in domestic pigs.
Wanninger, Sabrina; Donati, Manuela; Di Francesco, Antonietta; Hässig, Michael; Hoffmann, Karolin; Seth-Smith, Helena M B; Marti, Hanna; Borel, Nicole
In pigs, Chlamydia suis has been associated with respiratory disease, diarrhea and conjunctivitis, but there is a high rate of inapparent C. suis infection found in the gastrointestinal tract of pigs. Tetracycline resistance in C. suis has been described in the USA, Italy, Switzerland, Belgium, Cyprus and Israel. Tetracyclines are commonly used in pig production due to their broad-spectrum activity and relatively low cost. The aim of this study was to isolate clinical C. suis samples in cell culture and to evaluate their antibiotic susceptibility in vitro under consideration of antibiotic treatment on herd level. Swab samples (n = 158) identified as C. suis originating from 24 farms were further processed for isolation, which was successful in 71% of attempts with a significantly higher success rate from fecal swabs compared to conjunctival swabs. The farms were divided into three treatment groups: A) farms without antibiotic treatment, B) farms with prophylactic oral antibiotic treatment of the whole herd consisting of trimethoprime, sulfadimidin and sulfathiazole (TSS), or C) farms giving herd treatment with chlortetracycline with or without tylosin and sulfadimidin (CTS). 59 isolates and their corresponding clinical samples were selected and tested for the presence or absence of the tetracycline resistance class C gene [tet(C)] by conventional PCR and isolates were further investigated for their antibiotic susceptibility in vitro. The phenotype of the investigated isolates was either classified as tetracycline sensitive (Minimum inhibitory concentration [MIC] MIC MIC ≥ 4 μg/ml). Results of groups and individual pigs were correlated with antibiotic treatment and time of sampling (beginning/end of the fattening period). We found clear evidence for selective pressure as absence of antibiotics led to isolation of only tetracycline sensitive or intermediate strains whereas tetracycline treatment resulted in a greater number of tetracycline resistant isolates.
Full Text Available Helminth infection in pigs serves as an excellent model for the study of the interaction between human malnutrition and parasitic infection and could have important implications in human health. We had observed that pigs infected with Trichuris suis for 21 days showed significant changes in the proximal colon microbiota. In this study, interactions between worm burden and severity of disruptions to the microbial composition and metabolic potentials in the porcine proximal colon microbiota were investigated using metagenomic tools. Pigs were infected by a single dose of T. suis eggs for 53 days. Among infected pigs, two cohorts were differentiated that either had adult worms or were worm-free. Infection resulted in a significant change in the abundance of approximately 13% of genera detected in the proximal colon microbiota regardless of worm status, suggesting a relatively persistent change over time in the microbiota due to the initial infection. A significant reduction in the abundance of Fibrobacter and Ruminococcus indicated a change in the fibrolytic capacity of the colon microbiota in T. suis infected pigs. In addition, ∼10% of identified KEGG pathways were affected by infection, including ABC transporters, peptidoglycan biosynthesis, and lipopolysaccharide biosynthesis as well as α-linolenic acid metabolism. Trichuris suis infection modulated host immunity to Campylobacter because there was a 3-fold increase in the relative abundance in the colon microbiota of infected pigs with worms compared to naïve controls, but a 3-fold reduction in worm-free infected pigs compared to controls. The level of pathology observed in infected pigs with worms compared to worm-free infected pigs may relate to the local host response because expression of several Th2-related genes were enhanced in infected pigs with worms versus those worm-free. Our findings provided insight into the dynamics of the proximal colon microbiota in pigs in response to T
Wanninger, Sabrina; Donati, Manuela; Di Francesco, Antonietta; Hässig, Michael; Hoffmann, Karolin; Seth-Smith, Helena M. B.; Marti, Hanna; Borel, Nicole
In pigs, Chlamydia suis has been associated with respiratory disease, diarrhea and conjunctivitis, but there is a high rate of inapparent C. suis infection found in the gastrointestinal tract of pigs. Tetracycline resistance in C. suis has been described in the USA, Italy, Switzerland, Belgium, Cyprus and Israel. Tetracyclines are commonly used in pig production due to their broad-spectrum activity and relatively low cost. The aim of this study was to isolate clinical C. suis samples in cell culture and to evaluate their antibiotic susceptibility in vitro under consideration of antibiotic treatment on herd level. Swab samples (n = 158) identified as C. suis originating from 24 farms were further processed for isolation, which was successful in 71% of attempts with a significantly higher success rate from fecal swabs compared to conjunctival swabs. The farms were divided into three treatment groups: A) farms without antibiotic treatment, B) farms with prophylactic oral antibiotic treatment of the whole herd consisting of trimethoprime, sulfadimidin and sulfathiazole (TSS), or C) farms giving herd treatment with chlortetracycline with or without tylosin and sulfadimidin (CTS). 59 isolates and their corresponding clinical samples were selected and tested for the presence or absence of the tetracycline resistance class C gene [tet(C)] by conventional PCR and isolates were further investigated for their antibiotic susceptibility in vitro. The phenotype of the investigated isolates was either classified as tetracycline sensitive (Minimum inhibitory concentration [MIC] < 2 μg/ml), intermediate (2 μg/ml ≤ MIC < 4 μg/ml) or resistant (MIC ≥ 4 μg/ml). Results of groups and individual pigs were correlated with antibiotic treatment and time of sampling (beginning/end of the fattening period). We found clear evidence for selective pressure as absence of antibiotics led to isolation of only tetracycline sensitive or intermediate strains whereas tetracycline treatment
Dobbelaere, A; Jeannin, P; Bovyn, T; Ide, L
Due to the introduction of the conjugate vaccine against serotype b, neonatal sepsis caused by Haemophilus influenzae became very rare. There is little data in Belgium concerning the prevalence of H. influenzae early onset neonatal sepsis and articles about neonatal sepsis and H. influenzae published in the last decade are scarce. We report two invasive infections with a non-typeable H. influenzae. These cases show that neonatal sepsis caused by non-typeable H. influenzae may be underestimated and we believe that there is need for a better registration of this kind of infection.
Full Text Available Infective endocarditis is a common clinical problem in industrialized countries. Risk factors include abnormal cardiac valves, a history of endocarditis, intracardiac devices, prosthetic valves and intravenous drug use. We report a case of polymicrobial infective endocarditis in a 33 year-old female with a history chronic heroin use caused by Neisseria sicca and Haemophilus parainfluenzae. We believe the patient was exposed to these microbes by cleansing her skin with saliva prior to injection. Pairing a detailed history with the consideration of atypical agents is crucial in the proper diagnosis and management of endocarditis in patients with high-risk injection behaviors.
Asmussen, M D; Baugh, C. L.
The effect of a commercially available, chemically defined enrichment (Iso-VitaleX; BBL Microbiology Systems, Cockeysville, Md.) on the growth of 10 strains of Haemophilus somnus was studied. A 6- to 10-fold increase in growth, as measured turbidimetrically, was observed when Iso VitaleX was added to a basal medium of brain heart infusion broth to a final concentration of 1% (vol/vol). Thiamine pyrophosphate (cocarboxylase), a constituent component of Iso VitaleX, was found to be the only gro...
Pereira,Ricardo M.; Bucaretchi,Fabio; Tresoldi,Antonia T.
Objective: To report the case of a child with infective endocarditis caused by Haemophilus aphrophilus. Description: Boy with 20 days of fever and chills. On admission, he was febrile, pale and with no signs of hemodynamic instability; on cardiac auscultation, a mitral-related holosystolic murmur was observed. Laboratory examination identified anemia (hemoglobin = 9.14 g/dL), total leukocytes of 11,920 mm3, platelets of 250,000 mm3, elevated sedimentation velocity of red cells and elevated C-...
Edgardo Soriano Vargas; Horacio Raúl Terzolo
La bacteria Haemophilus paragallinarum es el agente causal de la coriza infecciosa, enfermedad que afecta el tracto respiratorio superior de los pollos. Ésta tiene impacto considerable en la avicultura, principalmente en granjas con edades múltiples. En este trabajo, se revisan las características bacteriológicas que establecen esta bacteria en la familia Pasteurellaceae y relacionarla con otros agentes potencialmente patógenos para las aves. Se da énfasis al conocimiento más reciente en cuan...
Notani, N.K.; Setlow, J.K.
Weigle reactivation of ultraviolet-irradiated HPlc1 phage was observed after ultraviolet or mitomycin C treatment of Haemophilus influenzae cells. The amount of reactivation was considerably increased when the treated cells were incubated in growth medium before infection. The presence of chloramphenicol during this incubation abolished the reactivation. No mutation of this phage accompanied the reactivation. When cells were treated so as to produce a maximal reactivation of phage, neither reactivation nor mutation of cells was observed. It is concluded that H. influenzae has an inducible repair system that is not accompanied by mutation.
Pickering, Janessa L; Prosser, Amy; Corscadden, Karli J; de Gier, Camilla; Richmond, Peter C; Zhang, Guicheng; Thornton, Ruth B; Kirkham, Lea-Ann S
Nontypeable Haemophilus influenzae (NTHi) is an opportunistic pathogen that resides in the upper respiratory tract and contributes to a significant burden of respiratory related diseases in children and adults. Haemophilus haemolyticus is a respiratory tract commensal that can be misidentified as NTHi due to high levels of genetic relatedness. There are reports of invasive disease from H. haemolyticus, which further blurs the species boundary with NTHi. To investigate differences in pathogenicity between these species, we optimized an in vitro epithelial cell model to compare the interaction of 10 H. haemolyticus strains with 4 NTHi and 4 H. influenzae-like haemophili. There was inter- and intra-species variability but overall, H. haemolyticus had reduced capacity to attach to and invade nasopharyngeal and bronchoalveolar epithelial cell lines (D562 and A549) within 3 h when compared with NTHi. H. haemolyticus was cytotoxic to both cell lines at 24 h, whereas NTHi was not. Nasopharyngeal epithelium challenged with some H. haemolyticus strains released high levels of inflammatory mediators IL-6 and IL-8, whereas NTHi did not elicit an inflammatory response despite higher levels of cell association and invasion. Furthermore, peripheral blood mononuclear cells stimulated with H. haemolyticus or NTHi released similar and high levels of IL-6, IL-8, IL-10, IL-1β, and TNFα when compared with unstimulated cells but only NTHi elicited an IFNγ response. Due to the relatedness of H. haemolyticus and NTHi, we hypothesized that H. haemolyticus may compete with NTHi for colonization of the respiratory tract. We observed that in vitro pre-treatment of epithelial cells with H. haemolyticus significantly reduced NTHi attachment, suggesting interference or competition between the two species is possible and warrants further investigation. In conclusion, H. haemolyticus interacts differently with host cells compared to NTHi, with different immunostimulatory and cytotoxic
Full Text Available An agar disc diffusion method was used to examine the sensitivity of 27 Haemophilus paragallinarum (Hpg isolates consisted of 23 local isolates, 4 standard isolates (serotype A and Escherichia coli ATCC 24922 as a control to eight antimicrobial drugs (ampicillin, erythromycin, oxytetracycline, doxycycline, neomycin, streptomycin, colistine and sulphanlethoxazole-trimethoprim . Twenty one out of 23 local isolates of Hpg were sensitive to doxycycline, 19 isolates to ampsllin, 18 isolates to oxytetracycline, 17 isolates to sulphametoxazole-trimethoprim, 16 isolates to erythromycin, and 13 isolates to neomycin, while 13 isolates were resistance to colistine and 11 isolates were also resistance to streptomycin .
Zheng, Pu; Fang, Lin; Xu, Yan; Dong, Jin-Jun; Ni, Ye; Sun, Zhi-Hao
Simultaneous saccharification and fermentation (SSF) technique was applied for succinic acid production by Actinobacillus succinogenes in a 5-l stirred bioreactor with corn stover as the raw material. The process parameters of SSF, including corn stover pretreatment condition, substrate concentration, enzyme loading and fermentation temperature were investigated. Results indicated that pretreating corn stover with diluted alkaline was beneficial for the succinic acid production, and succinic acid yield could be significantly increased when adding the cellulase supplemented with cellobiase. The maximal succinic acid concentration and yield could reach 47.4 g/l and 0.72 g/g-substrate, respectively. The corresponding operation conditions were summarized as follows: SSF operation at 38 °C for 48 h, diluted alkaline pretreated corn stover as substrate with concentration of 70 g/l, enzyme loading of 20FPU cellulase and 10 U cellobiase per gram substrate. This result suggested an industrial potential of succinic acid production by using SSF and corn stover.
The introduction into a naïve herd of animals sub-clinically infected with Actinobacillus pleuropneumoniae (App) is frequently the cause of clinical pleuropneumonia and the identification of such infected herds is a priority in the control of disease. Different serological tests for App have been developed and a number of these are routinely used. Some are species-specific whereas others identify more specifically the serotype/serogroup involved which requires updated information about important serotypes recovered from diseased pigs in a given area/country. Serotyping methods based on molecular techniques have been developed lately and are ready to be used by most diagnostic laboratories. When non-conclusive serological results are obtained, direct detection of App from tonsils is sometimes attempted. This review addresses different techniques and approaches used to monitor herds sub-clinically infected by this important pathogen. Copyright © 2015 Elsevier Ltd. All rights reserved.
Pérez Márquez, V M; Ochoa, J López; Cruz, C Vázquez; Alonso, P Sánchez; Olmedo-Alvarez, G; Vaca, S; Abascal, E Negrete
Actinobacillus pleuropneumoniae is the causal agent of porcine pleuropneumonia, which is a highly contagious respiratory disease that affects swine nearly exclusively. An isolate with characteristics of some Pasteurellaceae family members (Gram-negative bacterium, pleomorphic, and NAD-dependent) was isolated from layer hens showing clinical signs of infectious coryza. This bacterium presented hemolysis on rabbit red blood cell agar plates, and PCR amplification and sequencing of its 16S rDNA gene indicated 99% identity with A. pleuropneumoniae serotypes 3 and 7. The presence of a putative apxIIA gene was also determined by PCR. A single, smooth colony of this bacterium inoculated in five, 7-day-old chicken embryos via the yolk sac route induced 100% mortality. However, inoculation into 10-wk-old, specific-pathogen-free chickens induced only light facial swelling, and reisolation of the inoculated bacterium was negative.
Morioka, Ayako; Shimazaki, Yoko; Uchiyama, Mariko; Suzuki, Shoko
We observed increasing unserotypable (UT) Actinobacillus pleuropneumoniae isolates using agar gel diffusion (AGD) test. To reanalyze their serovar, we performed rapid slide agglutination (RSA) test and multiplex PCR for 47 UT isolates. Of these, 25 were serovar 1 (UT-serovar 1), 20 were serovar 2 (UT-serovar 2) and 2 were serovar 15 (UT-serovar 15). We examined serotyping antigen extraction temperature to determine heat influence. UT-serovar 1 and 15 were influenced by heat, because their precipitation lines were observed in the case of low antigen extraction temperature. To investigate the relationship between antigenicity and genotype, we performed pulsed-field gel electrophoresis (PFGE) analysis using UT-serovar 2 and 15. The predominant PFGE pattern of UT-serovar 2 was identical to that of serovar 2.
Yuan, Fangyan; Liu, Jinlin; Guo, Yi; Tan, Chen; Fu, Shulin; Zhao, Jin; Chen, Huanchun; Bei, Weicheng
Actinobacillus pleuropneumoniae is a Gram-negative pathogen that causes porcine pleuropneumonia. The pathogenicity of A. pleuropneumoniae is strongly correlated with the production of active repeat-in-toxin (RTX) proteins such as ApxIVA. We evaluated the contribution of a potential ApxIVA activator, ORF1, to the virulence and immunogenicity of A. pleuropneumoniae in pigs. The orf1 gene in A. pleuropneumoniae SLW03 (serovar 1, ΔapxICΔapxIIC) was deleted, producing strain SLW05 (ΔapxICΔapxIICΔorf1). The virulence of strains SLW03 and SLW05 was compared in pigs. Clinical signs and pulmonary lesions induced by strain SLW05 were slighter than that of strain SLW03 (P pleuropneumoniae serovar 1 or serovar 3 strain. Vaccination with strains SLW03 or SLW05 provided significantly greater protection compared to the negative control (P pleuropneumoniae infection.
Cişmileanu, Ana; Sima, Cornelia; Grigoriu, Constantin
A quantum dot - immunoglobulin conjugate specific for pig IgG, was obtained by carbodiimide chemistry. We used a Western blot technique for detecting specific antibodies against Actinobacillus pleuropneumoniae (A. pp), which cause porcine pleuropneumonia. The antigen used in this technique was Apx haemolysin which is an important virulence factor of A. pp and it induces protective immunity in vaccined pigs. The detection on Western blot membrane was possible at 1/50 dilution of quantum dot conjugate at a dilution of pig serum till 1/6400. The results for pig serum demonstrated a higher sensitivity of QD-based Western blot technique for the presence of antibodies specific for Apx haemolysin in comparison with similar classical techniques (with coloured substrate for enzyme present in secondary antibody conjugate).
Ito, Hiroya; Sueyoshi, Masuo
Nucleotide sequence determination and analysis of the cps gene involved in the capsular polysaccharide biosynthesis of Actinobacillus pleuropneumoniae serotype 15 revealed the presence of three open reading frames, designated as cps15ABC genes. At the protein level, Cps15A and Cps15B showed considerably high homology to CpsA (67.0 to 68.7%) and CpsB (31.7 to 36.8%), respectively, of A. pleuropneumoniae serotypes 1, 4 and 12, revealing the common genetic organization of the cps among serotypes 1, 4, 12 and 15. However, Cps15C showed no homology to any proteins of A. pleuropneumoniae serotypes, indicating that cps15C may be specific to serotype 15. This study will provide the basic molecular knowledge necessary for the development of diagnostics and a vaccine for A. pleuropneumoniae serotype 15.
Jacobsen, Mariann Juul; Nielsen, Jens Peter; Nielsen, Ragnhild
An aerosol infection model for inoculation of pigs with Actinobacillus pleuropneumoniae is described, With this model the virulence of three A. pleuropneumoniae biotype 1 strains representing serotypes 2, 5b and 6, and one Danish biotype 2 were compared using 13-week-old pigs for inoculation...... lesions was 10(9) CFU/ml. Repeated experiments confirmed these results showing similar virulence of serotypes 2, 5b and 6 whereas the biotype 2 strain proved less virulent, The aerosol infection model allowed a comparison of the number of A. pleuropneumoniae CFU/liter air which were necessary to induce...... lung lesions in susceptible pigs, This indicates that the model will be well suited for virulence studies of A. pleuropneumoniae serotypes in pigs....
Gram, T.; Ahrens, Peter; Nielsen, J.P.
A PCR for the detection of Actinobacillus pleuropneumoniae was evaluated. All of 102 field isolates of A. pleuropneumoniae reacted in the PCR by amplification of a 985 bp product. No PCR amplification product was observed when examining strains of A. ureae, A. capsulatus, A. hominis, A. equuli, A...... strains of A. lignieresii. The lower detection limit of the PCR test was 10(3) A. pleuropneumoniae CFU/PCR test tube and was not affected by addition of 10(6) E. coli CFU/PCR test tube. Mixed bacterial cultures from tonsils of 101 pigs from 9 different herds were tested by culture and by PCR using four...... mixed bacterial cultures. Tonsil cultures from 50 pigs from an A. pleuropneumoniae-negative herd did not react in the PCR. The results show that PCR on mixed bacterial cultures from tonsils may be a highly sensitive method for the detection of A. pleuropneumoniae in pig herds....
Full Text Available Abstract Background Actinobacillus pleuropneumoniae is the causative agent of porcine contagious pleuropneumonia, a highly contagious respiratory infection in pigs, and all the 15 serotypes are able to cause disease. Current vaccines including subunit vaccines could not provide satisfactory protection against A. pleuropneumoniae. In this study, the immunoproteomic approach was applied to the analysis of extracellular and outer membrane proteins of A. pleuropneumoniae JL03 serotype 3 for the identification of novel immunogenic proteins for A. pleuropneumoniae. Results A total of 30 immunogenic proteins were identified from outer membrane and extracellular proteins of JL03 serotype 3, of which 6 were known antigens and 24 were novel immunogenic proteins for A. pleuropneumoniae. Conclusion These data provide information about novel immunogenic proteins for A. pleuropneumoniae serotype 3, and are expected to aid in development of novel vaccines against A. pleuropneumoniae.
Andresen, Lars Ole; Jacobsen, M.J.; Nielsen, J.P.
The protective efficacy of an Actinobacillus pleuropneumoniae serotype 5b capsular polysaccharide-tetanus toroid conjugate (Ap5bCP-TT) against homologous challenge of pigs was investigated. Four pigs were non-vaccinated controls (group A), 4 pigs were injected with adjuvant without antigen (group B......) and 8 pigs were vaccinated with Ap5bCP-TT and adjuvant (group 0). Pigs vaccinated with Ap5bCP-TT developed antibody responses to the capsular polysaccharide from A. pleuropneumoniae serotype 5b (Ap5bCP). After challenge, all pigs in groups A and B had severe clinical signs of disease and were euthanized...... and pulmonary lesions caused by experimental infection with A. pleuropneumoniae serotype 5b....
Dubreuil, J.D.; Letellier, A.; Stenbæk, Eva
A polystyrene agglutination test has been developed for serotyping Actinobacillus pleuropneumoniae serotype 5a and 5b strains. Protein A-coated polystyrene microparticles were sensitized with a murine monoclonal antibody recognizing an epitope on serotype 5 LPS-O chain as shown by SDS......-PAGE and Western blotting, A total of 205 A. pleuropneumoniae, strains including all 12 serotype reference strains and 13 strains representing 8 common bacterial species associated with swine or related to A, pleuropneumoniae, were tested by mixing 25 mu L of polystyrene reagent with the same volume of a dense...... suspension of bacterial cells grown for 18 h. All A, pleuropneumoniae strains had been previously serotyped using standard procedures, The polystyrene agglutination test was rapid (less than 3 min) and easy to perform. Overall a very good correlation (97.3%) with the standard techniques was found...
LIU Jian-jie; HE Qi-gai; CHEN Huan-chun; WU Bin; XU Xiao-juan; LIU Jun-fa; TANG Xian-chun; BEI Wei-cheng
Based on the published nucleotide sequence of the apxICA of Actinobacillus pleuropneumoniaein Genbank(S4074), a pair of primers were designed. A 3 640 bp(4 687 -8 326 bp)gene fragment was ampli-fied by PCR from the isolated strain of A. pleuropneumoniae serovar 1. Then, it was cloned into pMD18-T,identified by both restriction endonuclease and sequence analysis, and inserted into pET-28a expression vectorto yield the expression plasmid. SDS-PAGE result indicated expression of apxICA in BL21 (DE3), Westernblot analysis showed the protein's immunogenicity. Using the expressed protein, ELISA was established to de-tect serum antibody against ApxI. The feature of ELISA to detect highly virulent A. pleuropneumoniae strainsinfection was proved by primary clinical application.
Podolska, Agnieszka; Anthon, Christian; Bak, Mads
Background: MicroRNAs (miRNAs) are a class of non-protein-coding genes that play a crucial regulatory role in mammalian development and disease. Whereas a large number of miRNAs have been annotated at the structural level during the latest years, functional annotation is sparse. Actinobacillus...... pleuropneumoniae (APP) causes serious lung infections in pigs. Severe damage to the lungs, in many cases deadly, is caused by toxins released by the bacterium and to some degree by host mediated tissue damage. However, understanding of the role of microRNAs in the course of this infectious disease in porcine......R-451 and miR-15a appear as very promising candidates for microRNAs involved in response to pathogen infection. Conclusions: This is the first study revealing significant differences in composition and expression profiles of miRNAs in lungs infected with a bacterial pathogen. Our results extend...
dos Santos, Fabrine Alexandre; de Azevedo, Edísio Oliveira; de Azevedo, Sérgio Santos; Garino Júnior, Felício; Mota, Rinaldo Aparecido; de Cássia Peixoto Kim, Pomy; Gomes, Ana Lisa Vale; Alves, Clebert José
The present study reports the first isolation of Actinobacillus seminis from a goat in Brazil. A four-year-old Moxotó breeding goat in a flock of 70 goats and 65 sheep reared together in the county of Patos, semiarid region of Northeastern Brazil, showed clinical signs of unilateral orchitis and epididymitis. Diagnosis of A. seminis infection was confirmed by association of clinical findings, bacterial isolation and 16S rRNA gene sequencing. This result suggests that A. seminis may be an additional cause of infertility in goats, and that sheep may be the source of infection because the mixed farming system allows the contact between sheep and goats in the semiarid region of Northeastern Brazil.
Fabrine Alexandre dos Santos
Full Text Available The present study reports the first isolation of Actinobacillus seminis from a goat in Brazil. A four-year-old Moxotó breeding goat in a flock of 70 goats and 65 sheep reared together in the county of Patos, semiarid region of Northeastern Brazil, showed clinical signs of unilateral orchitis and epididymitis. Diagnosis of A. seminis infection was confirmed by association of clinical findings, bacterial isolation and 16S rRNA gene sequencing. This result suggests that A. seminis may be an additional cause of infertility in goats, and that sheep may be the source of infection because the mixed farming system allows the contact between sheep and goats in the semiarid region of Northeastern Brazil.
Dubreuil, J.D.; Letellier, A.; Stenbæk, Eva;
A polystyrene agglutination test has been developed for serotyping Actinobacillus pleuropneumoniae serotype 5a and 5b strains. Protein A-coated polystyrene microparticles were sensitized with a murine monoclonal antibody recognizing an epitope on serotype 5 LPS-O chain as shown by SDS......-PAGE and Western blotting, A total of 205 A. pleuropneumoniae, strains including all 12 serotype reference strains and 13 strains representing 8 common bacterial species associated with swine or related to A, pleuropneumoniae, were tested by mixing 25 mu L of polystyrene reagent with the same volume of a dense...... suspension of bacterial cells grown for 18 h. All A, pleuropneumoniae strains had been previously serotyped using standard procedures, The polystyrene agglutination test was rapid (less than 3 min) and easy to perform. Overall a very good correlation (97.3%) with the standard techniques was found...
Prevalence of leukotoxic genotypes of Actinobacillus actinomycetemcomitans in Brazilians with chronic periodontitis Prevalência do genotipo leucotóxico de Actinobacillus actinomycetemcomitans em indivíduos brasileiros com periodontite crônica
Wilson Rosalem Junior; Arnaldo Feitosa Braga de Andrade; Ana Paula Vieira Colombo
Actinobacillus actinomycetemcomitans is considered a major etiologic agent of aggressive periodontitis but this species has also been associated with other forms of periodontal disease. Further, highly leukotoxic strains are related to severity of disease. This investigation determined the prevalence of A. actinomycetemcomitans and the occurrence of the leukotoxin gene 530-bp deletion in Brazilian subjects with chronic periodontitis. Twenty periodontally healthy and 20 chronic periodontitis s...
Laupland, Kevin B; Schønheyder, Henrik C; Østergaard, Christian
independently associated with death at 30-days in logistic regression analysis included male gender, hospital-onset disease, older age, and lower respiratory tract, central nervous system, or unknown focus of infection. CONCLUSIONS: Haemophilus influenzae is an important cause of morbidity and mortality......OBJECTIVES: Haemophilus influenzae is an important cause of invasive infection but contemporary data in non-selected populations is limited. METHODS: Population-based surveillance for Haemophilus influenzae bacteremia was conducted in seven regions in Australia, Canada, and Denmark during 2000...
Vieira, Rafael Felipe da Costa; Molento, Marcelo Beltrão; Guimarães, Ana Marcia Sa; Santos, Andrea Pires Dos; Bonat, Marcelo; Javorouski, Manoel Lucas; Popp, Luciene; Santos, Leonilda Correia Dos; Moraes, Wanderlei; Cubas, Zalmir Silvino; Vieira, Thállitha Samih Wischral Jayme; Vidotto, Odilon; Filho, Ivan Roque Barros; Biondo, Alexander Welker; Messick, Joanne Belle
Mycoplasma suis is a hemotropic bacteria of red blood cells and the causative agent of swine eperythrozoonosis. Diagnosis of infection may be reached by direct examination of blood smears; however, the use of polymerase chain reaction (PCR) of the 16S RNA gene of M. suis improves the sensitivity and specificity of detection. The aim of this study was to screen peccaries (Tayassu tajacu and T. pecari) for M. suis infection using a specific conventional PCR. A total of 28 blood samples from captive collared and white-lipped peccaries were collected, DNA extracted and a specific M. suis PCR assay performed. All samples were negatives by both blood smear examination and PCR testing. To verify the presence of amplifiable DNA, PCR for beta-actin gene was performed in all samples. This study was part of an active surveillance program, which is crucial for monitoring animal health status, particularly in wildlife species.
Studio osservazionale condotto presso la Dermatologia dell'Università di Bologna atto a valutare l'efficacia di methotrexate e, in particolare, la sua influenza sui titoli degli autoanticorpi patogeni nei pazienti affetti dalla malattia rara Pemfigoide Bolloso
Full Text Available Porcine pleuropneumonia is a highly contagious respiratory disease that causes great economic losses worldwide. In this study, we aimed to explore the underlying relationship between infection and injury by investigation of the whole porcine genome expression profiles of swine lung tissues post-inoculated with experimentally Actinobacillus pleuropneumoniae. Expression profiling experiments of the control group and the treatment group were conducted using a commercially available Agilent Porcine Genechip including 43,603 probe sets. Microarray analysis was conducted on profiles of lung from challenged versus non-challenged swine. We found 11,929 transcripts, identified as differentially expressed at the p ≤0.01 level. There were 1188 genes annotated as swine genes in the GenBank Data Base. GO term analysis identified a total of 89 biological process categories, 82 cellular components and 182 molecular functions that were significantly affected, and at least 27 biological process categories that were related to the host immune response. Gene set enrichment analysis identified 13 pathways that were significantly associated with host response. Many proinflammatory-inflammatory cytokines were activated and involved in the regulation of the host defense response at the site of inflammation; while the cytokines involved in regulation of the host immune response were suppressed. All changes of genes and pathways of induced or repressed expression not only led to a decrease in antigenic peptides presented to T lymphocytes by APCs via the MHC and alleviated immune response injury induced by infection, but also stimulated stem cells to produce granulocytes (neutrophils, eosinophils, and basophils and monocyte, and promote neutrophils and macrophages to phagocytose bacterial and foreign antigen at the site of inflammation. The defense function of swine infection with Actinobacillus pleuropneumoniae was improved, while its immune function was decreased.
Full Text Available Abstract Background MicroRNAs (miRNAs are a class of non-protein-coding genes that play a crucial regulatory role in mammalian development and disease. Whereas a large number of miRNAs have been annotated at the structural level during the latest years, functional annotation is sparse. Actinobacillus pleuropneumoniae (APP causes serious lung infections in pigs. Severe damage to the lungs, in many cases deadly, is caused by toxins released by the bacterium and to some degree by host mediated tissue damage. However, understanding of the role of microRNAs in the course of this infectious disease in porcine is still very limited. Results In this study, the RNA extracted from visually unaffected and necrotic tissue from pigs infected with Actinobacillus pleuropneumoniae was subjected to small RNA deep sequencing. We identified 169 conserved and 11 candidate novel microRNAs in the pig. Of these, 17 were significantly up-regulated in the necrotic sample and 12 were down-regulated. The expression analysis of a number of candidates revealed microRNAs of potential importance in the innate immune response. MiR-155, a known key player in inflammation, was found expressed in both samples. Moreover, miR-664-5p, miR-451 and miR-15a appear as very promising candidates for microRNAs involved in response to pathogen infection. Conclusions This is the first study revealing significant differences in composition and expression profiles of miRNAs in lungs infected with a bacterial pathogen. Our results extend annotation of microRNA in pig and provide insight into the role of a number of microRNAs in regulation of bacteria induced immune and inflammatory response in porcine lung.
Alrousan, Enas; Fan, Xin
An important virulence strategy adopted by Haemophilus influenzae to establish a niche on the mucosal surface of the host is the phosphorylcholine (ChoP) decoration of its lipopolysaccharides, which promotes adherence to the host cells. Haemophilus influenzae is able to use glycerophosphorylcholine (GPC) from host for ChoP synthesis. Utilization of GPC requires glpQ, which encodes a glycerophosphodiester phosphodiesterase enzyme. In this study, we investigate the transcriptional regulation of glpQ gene using real-time PCR and transcriptional fusion of H. influenzae glpQ promoter to the Escherichia coli lacZ reporter gene. The glpQ promoter activities were examined under environmental conditions including changes in temperature, oxygen, high salt and minimal growth medium. Our data showed that under room temperature and anaerobic conditions, the glpQ gene expression levels were significantly higher than under other growth conditions. In addition, the glpQ gene expression levels were upregulated in the presence of GPC. These results suggest that H. influenzae may upregulate glpQ expression in response to different environments it encounters during infection, from the airway surfaces (room temperature) to deep tissues (anaerobic). Upregulation of glpQ by GPC may allow efficient use of abundant GPC from mammalian cells by H. influenzae as a source of nutrient and for ChoP decoration of lipopolysaccharide that facilitates bacterial adhesion to host cells and growth during infection.
Singh, Vivek; Nanjappa, Sowmya; Pabbathi, Smitha; Greene, John N
A major cause of morbidity and mortality in patients with cancer is infection. Since the introduction of the Haemophilus influenzae type b (Hib) vaccine in the United States in the 1990s, invasive H influenzae infection has become less common. We report on 5 patients with cancer and invasive H influenzae infection. A literature review was also performed of the dominant Haemophilus subtype and the clinical features associated with the infection and concomitant cancer. Of the 17 cases found in the literature, had hematological malignancies and 1 case each had thymoma, schwannoma, teratoma, and pancreatic, Merkel cell, pharyngeal, laryngeal, and rectal carcinomas. Two cases occurred with AIDS and Kaposi sarcoma. Pneumonia with bacteremia was seen in 8 cases, whereas pleuritis, neck cellulitis, septic arthritis, meningitis, and mediastinitis were diagnosed in the others. No focus of infection was identified in 2 cases. Nontypable H influenzae (NTHi) occurred in 4 cases, and Hib was isolated in 2 cases; serotyping was not reported in the others. Leukocytosis occurred in 7 cases and lymphopenia in 3; no cases presented with neutropenia. Four isolates were positive for beta-lactamase. Susceptibility data were unavailable in 5 case patients. Among serotyped cases, 67% were of the NTHi strain - a finding consistent with the change in the epidemiology of H influenzae since the introduction of the Hib vaccine.
Simpson, Jodie L; Daly, Joshua; Baines, Katherine J; Yang, Ian A; Upham, John W; Reynolds, Paul N; Hodge, Sandra; James, Alan L; Hugenholtz, Philip; Willner, Dana; Gibson, Peter G
Asthma is a chronic inflammatory disorder of the airways where bacteria may act as protagonists of chronic inflammation. Little is known about the relation of airway inflammation to the presence of specific bacterial taxa. We sought to describe the sputum microbiome in adults with poorly controlled asthma.DNA was extracted from induced sputum and microbial communities were profiled using 16S rRNA pyrosequencing. Bacterial species were characterised, and the relationship between microbial populations, asthma inflammatory subtypes and other covariates was explored. Real-time PCR was used to identify Tropheryma whipplei and Haemophilus influenzae in sputum.Adults with neutrophilic asthma had reduced bacterial diversity and species richness. Tropheryma was identified and confirmed with real-time PCR in 12 (40%) participants. Haemophilus occurred most often in a group of younger atopic males with an increased proportion of neutrophils. PCR confirmed the presence of H. influenzae in 35 (76%) participants with poorly controlled asthma.There are phenotype-specific alterations to the airway microbiome in asthma. Reduced bacterial diversity combined with a high prevalence of H. influenzae was observed in neutrophilic asthma, whereas eosinophilic asthma had abundant T. whipplei.
Benga, Laurentiu; Fulde, Marcus; Neis, Christina; Goethe, Ralph; Valentin-Weigand, Peter
Streptococcus suis is a major cause of meningitis, sepsis and arthritis in piglets and a zoonotic agent. Survival in the blood circulation system represents a major step in pathogenesis of S. suis infections. To get further insights into the mechanisms of S. suis survival in the host, we compared a highly virulent S. suis serotype 2 strain with its non-encapsulated and suilysin-deficient mutants in their abilities to resist phagocytosis and killing by polymorphonuclear neutrophils (PMNs) and mononuclear cells. PMNs displayed a higher capacity to take up encapsulated bacteria than mononuclear cells, whereas both cell types internalized efficiently non-encapsulated S. suis. Differentiation of extracellular and intracellular survival of the WT strain revealed that in PMNs the majority of the cell-associated streptococci were intracellular, whereas in mononuclear cells the majority remained attached to the cell surface. S. suis survived mainly extracellularly, since both cells killed intracellular bacteria to a similar extent. As a consequence of different resistance to phagocytosis, only the encapsulated S. suis strains survived co-cultivation with PMNs. Comparison of the WT strain with its encapsulated suilysin-deficient mutant revealed reduced survival of the mutant after co-cultivation with PMNs. Involvement of suilysin in inhibition of phagocytosis was further confirmed by the use of anti-suilysin antibodies and recombinant suilysin. Kinetic experiments with PMNs suggested that reduced survival of the mutant strain was mainly associated with an increased uptake, whilst both strains adhered similarly. Concluding, our results indicate that the capsule and the suilysin play important roles in S. suis survival in the host by interfering with phagocytic uptake.
Wang, Xiangguo; Lin, Pengfei; Li, Yang; Xiang, Caixia; Yin, Yanlong; Chen, Zhi; Du, Yue; Zhou, Dong; Jin, Yaping; Wang, Aihua
Brucella has been reported to impair placental trophoblasts, a cellular target where Brucella efficiently replicates in association with the endoplasmic reticulum (ER), and ultimately trigger abortion in pregnant animals. However, the precise effects of Brucella on trophoblast cells remain unclear. Here, we describe the infection and replication of Brucella suis vaccine strain 2 (B.suis.S2) in goat trophoblast cells (GTCs) and the cellular and molecular responses induced in vitro. Our studies demonstrated that B.suis.S2 was able to infect and proliferate to high titers, hamper the proliferation of GTCs and induce apoptosis due to ER stress. Tunicamycin (Tm), a pharmacological chaperone that strongly mounts ER stress-induced apoptosis, inhibited B.suis.S2 replication in GTCs. In addition, 4 phenyl butyric acid (4-PBA), a pharmacological chaperone that alleviates ER stress-induced apoptosis, significantly enhanced B.suis.S2 replication in GTCs. The Unfolded Protein Response (UPR) chaperone molecule GRP78 also promoted B.suis.S2 proliferation in GTCs by inhibiting ER stress-induced apoptosis. We also discovered that the IRE1 pathway, but not the PERK or ATF6 pathway, was activated in the process. However, decreasing the expression of phosphoIRE1α and IRE1α proteins with Irestatin 9389 (IRE1 antagonist) in GTCs did not affect the proliferation of B.suis.S2. Although GTC implantation was not affected upon B.suis.S2 infection, progesterone secretion was suppressed, and prolactin and estrogen secretion increased; these effects were accompanied by changes in the expression of genes encoding key steroidogenic enzymes. This study systematically explored the mechanisms of abortion in Brucella infection from the viewpoint of pathogen invasion, ER stress and reproductive endocrinology. Our findings may provide new insight for understanding the mechanisms involved in goat abortions caused by Brucella infection.
Full Text Available Brucella has been reported to impair placental trophoblasts, a cellular target where Brucella efficiently replicates in association with the endoplasmic reticulum (ER, and ultimately trigger abortion in pregnant animals. However, the precise effects of Brucella on trophoblast cells remain unclear. Here, we describe the infection and replication of Brucella suis vaccine strain 2 (B.suis.S2 in goat trophoblast cells (GTCs and the cellular and molecular responses induced in vitro. Our studies demonstrated that B.suis.S2 was able to infect and proliferate to high titers, hamper the proliferation of GTCs and induce apoptosis due to ER stress. Tunicamycin (Tm, a pharmacological chaperone that strongly mounts ER stress-induced apoptosis, inhibited B.suis.S2 replication in GTCs. In addition, 4 phenyl butyric acid (4-PBA, a pharmacological chaperone that alleviates ER stress-induced apoptosis, significantly enhanced B.suis.S2 replication in GTCs. The Unfolded Protein Response (UPR chaperone molecule GRP78 also promoted B.suis.S2 proliferation in GTCs by inhibiting ER stress-induced apoptosis. We also discovered that the IRE1 pathway, but not the PERK or ATF6 pathway, was activated in the process. However, decreasing the expression of phosphoIRE1α and IRE1α proteins with Irestatin 9389 (IRE1 antagonist in GTCs did not affect the proliferation of B.suis.S2. Although GTC implantation was not affected upon B.suis.S2 infection, progesterone secretion was suppressed, and prolactin and estrogen secretion increased; these effects were accompanied by changes in the expression of genes encoding key steroidogenic enzymes. This study systematically explored the mechanisms of abortion in Brucella infection from the viewpoint of pathogen invasion, ER stress and reproductive endocrinology. Our findings may provide new insight for understanding the mechanisms involved in goat abortions caused by Brucella infection.
Jungersen, Gregers; Sørensen, Vibeke; Giese, Steen Bjørck
responses in a YeO:9-purified O-antigen indirect ELISA did not decrease accordingly. Analysis of available cross-sectional serum samples from pig herds naturally infected with YeO: 9 or B. suis biovar 2 confirmed that the observed difference in the duration of the serological responses between the two...... infections could be used to discriminate between herds infected with B. suis biovar 2 and YeO:9....
Full Text Available Abstract Hemotrophic mycoplasmas (HM are highly specialized red blood cell parasites that cause infectious anemia in a variety of mammals, including humans. To date, no in vitro cultivation systems for HM have been available, resulting in relatively little information about the pathogenesis of HM infection. In pigs, Mycoplasma suis-induced infectious anemia is associated with hemorrhagic diathesis, and coagulation dysfunction. However, intravasal coagulation and subsequent consumption coagulopathy can only partly explain the sequence of events leading to hemorrhagic diathesis manifesting as cyanosis, petechial bleeding, and ecchymosis, and to disseminated coagulation. The involvement of endothelial activation and damage in M. suis-associated pathogenesis was investigated using light and electron microscopy, immunohistochemistry, and cell sorting. M. suis interacted directly with endothelial cells in vitro and in vivo. Endothelial activation, widespread endothelial damage, and adherence of red blood cells to the endothelium were evident in M. suis-infected pigs. These alterations of the endothelium were accompanied by hemorrhage, intravascular coagulation, vascular occlusion, and massive morphological changes within the parenchyma. M. suis biofilm-like microcolonies formed on the surface of endothelial cells, and may represent a putative persistence mechanism of M. suis. In vitro analysis demonstrated that M. suis interacted with the endothelial cytoskeletal protein actin, and induced actin condensation and activation of endothelial cells, as determined by the up-regulation of ICAM, PECAM, E-selectin, and P-selectin. These findings demonstrate an additional cell tropism of HM for endothelial cells and suggest that M. suis interferes with the protective function of the endothelium, resulting in hemorrhagic diathesis.
Nutravong, Thitima; Angkititrakul, Sunpetch; Jiwakanon, Netchanok; Wongchanthong, Wanlaya; Dejsirilerts, Surang; Nawa, Yukifumi
Streptococcus suis serotype 2 infections occur in many provinces of north-eastern Thailand, knowledge concerning the prevalence of the common S. suis serotypes (1, 1/2, 2, 5, 7, 8, 9, 14 and 16) among healthy and diseased pigs in upper northeastern Thailand remains limited. This study investigated S. suis isolates from pigs (healthy and diseased) and also from humans using 11 conventional biochemical tests, 16S rDNA PCR and sequence analysis and multiplex PCR genotyping of porcine cps and gdh. Thirty-three isolates were obtained between 2009 and 2012 from blood or cerebrospinal fluid of patients from northeastern Thailand previously diagnosed with S. suis infection, based on clinical symptoms and laboratory diagnosis using 11 biochemical tests and PCR detection of 16S rDNA and cps. Eleven S. suis isolates were obtained between 2006 and 2009 from diseased pigs with clinical signs and laboratory diagnoses. In addition, 43 isolates obtained from 741 nasal swab cultures of slaughtered pigs between 2011 and 2012 were included. All three methods showed similar sensitivity in detection of S. suis from clinical and diseased pig specimens, although in healthy pigs, the 11 conventional biochemical methods yielded 2.3% false positives, and the gdh PCR detection method exhibited 31% false negatives. S. suis was present among healthy pigs in 8 of 10 provinces in upper northeastern Thailand, giving an average prevalence of 5.7% (range 1%-17%) using conventional methods together with 16S rDNA PCR assay. False positives by conventional methods were due to species with similar phenotypes, such as viridian streptococci, and are not statistically different from those obtained with the 16S rDNA PCR method, and the false negatives using gdh PCR assay will require further investigation. As S. suis was recovered from both diseased and healthy pigs, raw or undercooked pork products should be considered unsafe for handling or consumption in these regions of Thailand.
Subashchandrabose, Sargurunathan; LeVeque, Rhiannon M.; Wagner, Trevor K.; Kirkwood, Roy N; Kiupel, Matti; Mulks, Martha H.
In Actinobacillus pleuropneumoniae, which causes porcine pleuropneumonia, ilvI was identified as an in vivo-induced (ivi) gene and encodes the enzyme acetohydroxyacid synthase (AHAS) required for branched-chain amino acid (BCAA) biosynthesis. ilvI and 7 of 32 additional ivi promoters were upregulated in vitro when grown in chemically defined medium (CDM) lacking BCAA. Based on these observations, we hypothesized that BCAA would be found at limiting concentrations in pulmonary secretions and t...
Kang, Philip; Korostoff, Jonathan; Volgina, Alla; Grzesik, Wojciech; DiRienzo, Joseph M.
The periodontal pathogen Actinobacillus actinomycetemcomitans expresses a cytolethal distending toxin (CDT) that typically arrests the growth of eukaryotic cells at either the G0/G1 or G2/M phase of the cell cycle. It was previously found that CDT failed to arrest the growth of human periodontal ligament fibroblasts (HPLFs) when grown in pure culture. In contrast, proliferation of an oral epithelial cell line was rapidly inhibited by the toxin. In this study, the feasibility of using mixed-ce...
Stenbæk, Eva I.; DeLaSalle, F.; Gottschalk, M.
inhibition of the MAb 210-F11. Pig serum from specific pathogen free (SPF) herds, from experimentally infected animals, and from acutely and chronically infected herds were tested, A serum dilution of 1/30 was found to be optimal, when using 50% inhibition as the discriminating inhibition percentage....... No cross-reactivity was observed with serum from pigs infected with other App serotypes or bacteria isolated from the respiratory tract, such as A. suis and H. parasuis. The inhibition EIA will be used for surviellance of App-5 antibodies in SPF and conventional herds....
Xiao, Genhui; Wu, Zongfu; Zhang, Shouming; Tang, Huanyu; Wang, Fengqiu; Lu, Chengping
Streptococcus suis is a major pathogen of pigs and also an important zoonotic agent for humans. A S. suis protein containing Mac-1 domain (designated Mac) is a protective antigen, exclusively cleaves porcine IgM, and contributes to complement evasion with the presence of high titers of specific porcine anti-S. suis IgM, but its role in S. suis virulence has not been investigated in natural healthy host without specific IgM. In this study, a mac deletion mutant was constructed by homologous recombination in S. suis serotype 2 virulent reference strain P1/7. Deletion of mac did not significantly influence phagocytosis or intracellular survival within murine macrophages RAW264.7, or the oxidative-burst induction of RAW264.7 and murine neutrophils. Furthermore, the mutant is as virulent as the wild-type strain in pig, mouse, and zebrafish infection models. Our data suggest that Mac is not essential for S. suis virulence in strain P1/7 in natural healthy host without specific IgM, and the immunogenicity of Mac does not appear to correlate with its significance for virulence.
Post, Deborah M B; Ketterer, Margaret R; Coffin, Jeremy E; Reinders, Lorri M; Munson, Robert S; Bair, Thomas; Murphy, Timothy F; Foster, Eric D; Gibson, Bradford W; Apicella, Michael A
Haemophilus haemolyticus and nontypeable Haemophilus influenzae (NTHi) are closely related upper airway commensal bacteria that are difficult to distinguish phenotypically. NTHi causes upper and lower airway tract infections in individuals with compromised airways, while H. haemolyticus rarely causes such infections. The lipooligosaccharide (LOS) is an outer membrane component of both species and plays a role in NTHi pathogenesis. In this study, comparative analyses of the LOS structures and corresponding biosynthesis genes were performed. Mass spectrometric and immunochemical analyses showed that NTHi LOS contained terminal sialic acid more frequently and to a higher extent than H. haemolyticus LOS did. Genomic analyses of 10 strains demonstrated that H. haemolyticus lacked the sialyltransferase genes lic3A and lic3B (9/10) and siaA (10/10), but all strains contained the sialic acid uptake genes siaP and siaT (10/10). However, isothermal titration calorimetry analyses of SiaP from two H. haemolyticus strains showed a 3.4- to 7.3-fold lower affinity for sialic acid compared to that of NTHi SiaP. Additionally, mass spectrometric and immunochemical analyses showed that the LOS from H. haemolyticus contained phosphorylcholine (ChoP) less frequently than the LOS from NTHi strains. These differences observed in the levels of sialic acid and ChoP incorporation in the LOS structures from H. haemolyticus and NTHi may explain some of the differences in their propensities to cause disease.
Post, Deborah M. B.; Ketterer, Margaret R.; Coffin, Jeremy E.; Reinders, Lorri M.; Munson, Robert S.; Bair, Thomas; Murphy, Timothy F.; Foster, Eric D.; Gibson, Bradford W.
Haemophilus haemolyticus and nontypeable Haemophilus influenzae (NTHi) are closely related upper airway commensal bacteria that are difficult to distinguish phenotypically. NTHi causes upper and lower airway tract infections in individuals with compromised airways, while H. haemolyticus rarely causes such infections. The lipooligosaccharide (LOS) is an outer membrane component of both species and plays a role in NTHi pathogenesis. In this study, comparative analyses of the LOS structures and corresponding biosynthesis genes were performed. Mass spectrometric and immunochemical analyses showed that NTHi LOS contained terminal sialic acid more frequently and to a higher extent than H. haemolyticus LOS did. Genomic analyses of 10 strains demonstrated that H. haemolyticus lacked the sialyltransferase genes lic3A and lic3B (9/10) and siaA (10/10), but all strains contained the sialic acid uptake genes siaP and siaT (10/10). However, isothermal titration calorimetry analyses of SiaP from two H. haemolyticus strains showed a 3.4- to 7.3-fold lower affinity for sialic acid compared to that of NTHi SiaP. Additionally, mass spectrometric and immunochemical analyses showed that the LOS from H. haemolyticus contained phosphorylcholine (ChoP) less frequently than the LOS from NTHi strains. These differences observed in the levels of sialic acid and ChoP incorporation in the LOS structures from H. haemolyticus and NTHi may explain some of the differences in their propensities to cause disease. PMID:26729761
Full Text Available Streptococcus suis (S. suis infection is considered to be a major problem in the swine industry worldwide. Based on the capsular type, 33 serotypes of S. suis have been described, with serotype 2 (SS2 being the most frequently isolated from diseased piglets. Little is known, however, about the pathogenesis and virulence factors of S. suis. Research on bacteriophages highlights a new area in S. suis research. A S. suis serotype 2 bacteriophage, designated SMP, has been previously isolated in our laboratory. Here, we selected a lysogenic isolate in which the SMP phage was integrated into the chromosome of strain SS2-4. Compared to the wild-type isolate, the lysogenic strain showed increased mortality in zebra fish. Moreover the sensitivity of the lysogenic strain to lysozyme was seven times higher than that of the wild-type.
Tang, Fang; Zhang, Wei; Lu, Chengping
Streptococcus suis (S. suis) infection is considered to be a major problem in the swine industry worldwide. Based on the capsular type, 33 serotypes of S. suis have been described, with serotype 2 (SS2) being the most frequently isolated from diseased piglets. Little is known, however, about the pathogenesis and virulence factors of S. suis. Research on bacteriophages highlights a new area in S. suis research. A S. suis serotype 2 bacteriophage, designated SMP, has been previously isolated in our laboratory. Here, we selected a lysogenic isolate in which the SMP phage was integrated into the chromosome of strain SS2-4. Compared to the wild-type isolate, the lysogenic strain showed increased mortality in zebra fish. Moreover the sensitivity of the lysogenic strain to lysozyme was seven times higher than that of the wild-type.
Meekums, Hayley; Hawash, Mohamed B F; Sparks, Alexandra M;
BACKGROUND: Since the nematodes Trichuris trichiura and T. suis are morphologically indistinguishable, genetic analysis is required to assess epidemiological cross-over between people and pigs. This study aimed to clarify the transmission biology of trichuriasis in Ecuador. FINDINGS: Adult...... Trichuris worms were collected during a parasitological survey of 132 people and 46 pigs in Esmeraldas Province, Ecuador. Morphometric analysis of 49 pig worms and 64 human worms revealed significant variation. In discriminant analysis morphometric characteristics correctly classified male worms according...... to genetically analyse Trichuris parasites. Although T. trichiura does not appear to be zoonotic in Ecuador, there is evidence of genetic exchange between T. trichiura and T. suis warranting more detailed genetic sampling....
Ottow, M. K.; Klaver, E. J.; van der Pouw Kraan, T. C. T. M.
-CSF)-differentiated) macrophages. Interestingly, we here show that T. suis SPs potently skew inflammatory macrophages into a more anti-inflammatory state in a Toll-like receptor 4 (TLR4)-dependent manner, and less effects are seen when stimulating macrophages with TLR2 or -3 ligands. Gene microarray analysis of GM......Recent clinical trials in patients with inflammatory diseases like multiple sclerosis (MS) or inflammatory bowel disease (IBD) have shown the beneficial effects of probiotic helminth administration, although the underlying mechanism of action remains largely unknown. Potential cellular targets may...... include innate immune cells that propagate inflammation in these diseases, like pro-inflammatory macrophages. We here investigated the effects of the helminth Trichuris suis soluble products (SPs) on the phenotype and function of human inflammatory (granulocyte-macrophage colony-stimulating factor (GM...
Qiong-Ying DENG; Chuan-Chao WANG; Xiao-Qing WANG; Ling-Xiang WANG; Zhong-Yan WANG; Wen-Jun WU; Hui LI
The origins of Kam-Sui speaking Chadong and Mulam people have been controversial subjects in ethnic history studies and other related fields.Here,we studied Y chromosome (40 informative single nucleotide polymorphisms and 17 short tandem repeats in a non-recombining region) and mtDNA (hypervariable segment I and coding region single nucleotide polymorphisms) diversities in 50 Chadong and 93 Mulam individuals.The Y chromosome and mtDNA haplogroup components and network analyses indicated that both Chadong and Mulam originated from the admixture between surrounding populations and the indigenous Kam-Sui populations.The newly found Chadong is more closely related to Mulam than to Maonan,especially in the matemal lineages.
Hansen, Eline Palm; Kringel, Helene; Thamsborg, Stig Milan;
microRNAs (miRNAs) are recently discovered as key regulators of gene translation and are becoming increasingly recognized for their involvement in various diseases. This study investigates the miRNA profile in pig serum during the course of an infection with the gastrointestinal parasite, Trichuris...... for asthma and we hypothesize possible interactions between these host- and parasite-derived miRNAs and their immunomodulating roles....... suis. Of this panel, the expression of selected miRNAs in serum from T. suis infected and uninfected pigs were determined by quantitative real time PCR using Exiqon Human Panel assays at 0, 2, 4, 6, 8 and 10 weeks post first infection (wpi). One miRNA, ssc-let-7d-3p, was significantly up...
As the capital of the Sui and Tang dynasties,Chang'an brought together large numbers of high-ranking officials,aristocrats,local residents,and sojourners.The promise of profits caused by the high demand for consumer goods attracted merchants.Chang'an was also the starting point of the renowned Silk Road.For all these reasons,Chang'an became a gathering point for Small and medium-scale merchants,rich merchants,ethnic-minority merchants,and foreign merchants.All these merchants engaged in a wide variety of business activities and made money by surprisingly diverse means.Those with great economic power were quite active politically.The activities of these merchants symbolize the unprecedented growth of commerce in Chang'an and reveal the high level of development of urban trade in the Sui and the Tang dynasties.
Mejer, Helena; Roepstorff, Allan Knud
Transmission of Oesophagostomum dentatum and Trichuris suis was studied in outdoor reared pigs. Six farrowing paddocks were naturally contaminated in May to mid-June 2001 by experimentally infected seeder pigs. Early July, 1 sow farrowed on each paddock and starting week 3 post partum (p.......p.) the offspring was slaughtered serially every 2 weeks for parasite recovery. Faeces were collected regularly for parasite egg counts and acid-insoluble ash (AIA) content as an indicator of geophagy. Weaning took place week 7 p.p. by removing the sow. Paddock infection levels were estimated in mid-June (O....... dentatum) and late November (O. dentatum and T. suis) using helminth naïve tracer pigs. Soil and vegetation samples were collected regularly. Despite a high initial contamination by the seeder pigs, O. dentatum paddock infectivity was negligible to low throughout the raising of the experimental piglets...
de Neeling AJ; Overbeek BP; Timmerman CP; de Jong J; Dessens-Kroon M; van Klingeren B
The susceptibility to antibiotics of three respiratory pathogens, Haemophilus influenzae, Streptococcus pneumoniae and Moraxella catarrhalis, was determined. The isolates were obtainied in three regional laboratories in the Netherlands and tested using the microdilution method. After incubation th
McNicol, P J; Albritton, W L; Ronald, A R
Haemophilus species have been implicated as the source of plasmid-mediated ampicillin resistance in Neisseria gonorrhoeae. Previous attempts to transfer conjugally the resistance plasmids from Haemophilus species to N. gonorrhoeae have met with limited success. Using both biparental and triparental mating systems, it was found that transfer will occur if the commensal Neisseria species, Neisseria cinerea, is used as a transfer intermediate. This organism stably maintains resistance plasmids of Haemophilus and facilitates transfer of these plasmids to N. gonorrhoeae, in a triparental mating system, at a transfer frequency of 10(-8). Both Haemophilus ducreyi and N. gonorrhoeae carry mobilizing plasmids capable of mediating conjugal transfer of the same resistance plasmids. However, restriction endonuclease mapping and DNA hybridization studies indicate that the mobilizing plasmids are distinctly different molecules. Limited homology is present within the transfer region of these plasmids.
Mussa, Huda J; VanWagoner, Timothy M; Morton, Daniel J; Seale, Thomas W; Whitby, Paul W; Stull, Terrence L
Nontypeable Haemophilus influenzae is an important cause of human disease. Strains were selected for genome sequencing to represent the breadth of nontypeable strains within the species, as previously defined by the electrophoretic mobility of 16 metabolic enzymes.
A.F. van Belkum (Alex); S. Scherer; D. Willemse; L. van Alphen (Loek); H.A. Verbrugh (Henri); W.B. van Leeuwen (Willem)
textabstractAn algorithm capable of identifying short repeat motifs was developed and used to screen the whole genome sequence available for Haemophilus influenzae, since some of these repeats have been shown to affect bacterial virulence. Various di- to hexanucleotide
Full Text Available Helicobacter (H. suis colonizes the stomach of the majority of pigs as well as a minority of humans worldwide. Infection causes chronic inflammation in the stomach of the host, however without an effective clearance of the bacteria. Currently, no information is available about possible mechanisms H. suis utilizes to interfere with the host immune response. This study describes the effect on various lymphocytes of the γ-glutamyl transpeptidase (GGT from H. suis. Compared to whole cell lysate from wild-type H. suis, lysate from a H. suis ggt mutant strain showed a decrease of the capacity to inhibit Jurkat T cell proliferation. Incubation of Jurkat T cells with recombinantly expressed H. suis GGT resulted in an impaired proliferation, and cell death was shown to be involved. A similar but more pronounced inhibitory effect was also seen on primary murine CD4(+ T cells, CD8(+ T cells, and CD19(+ B cells. Supplementation with known GGT substrates was able to modulate the observed effects. Glutamine restored normal proliferation of the cells, whereas supplementation with reduced glutathione strengthened the H. suis GGT-mediated inhibition of proliferation. H. suis GGT treatment abolished secretion of IL-4 and IL-17 by CD4(+ T cells, without affecting secretion of IFN-γ. Finally, H. suis outer membrane vesicles (OMV were identified as a possible delivery route of H. suis GGT to lymphocytes residing in the deeper mucosal layers. Thus far, this study is the first to report that the effects on lymphocytes of this enzyme, not only important for H. suis metabolism but also for that of other Helicobacter species, depend on the degradation of two specific substrates: glutamine and reduced glutatione. This will provide new insights into the pathogenic mechanisms of H. suis infection in particular and infection with gastric helicobacters in general.
Willenborg, J; Fulde, M; de Greeff, A; Rohde, M; Smith, H E; Valentin-Weigand, P; Goethe, R
Streptococcus suis is one of the most important pathogens in pigs and is also an emerging zoonotic agent. After crossing the epithelial barrier, S. suis causes bacteraemia, resulting in meningitis, endocarditis and bronchopneumonia. Since the host environment seems to be an important regulatory component for virulence, we related expression of virulence determinants of S. suis to glucose availability during growth and to the sugar metabolism regulator catabolite control protein A (CcpA). We found that expression of the virulence-associated genes arcB, representing arcABC operon expression, cps2A, representing capsular locus expression, as well as sly, ofs, sao and epf, differed significantly between exponential and early stationary growth of a highly virulent serotype 2 strain. Deletion of ccpA altered the expression of the surface-associated virulence factors arcB, sao and eno, as well as the two currently proven virulence factors in pigs, ofs and cps2A, in early exponential growth. Global expression analysis using a cDNA expression array revealed 259 differentially expressed genes in early exponential growth, of which 141 were more highly expressed in the CcpA mutant strain 10ΔccpA and 118 were expressed to a lower extent. Interestingly, among the latter genes, 18 could be related to capsule and cell wall synthesis. Correspondingly, electron microscopy characterization of strain 10ΔccpA revealed a markedly reduced thickness of the capsule. This phenotype correlated with enhanced binding to porcine plasma proteins and a reduced resistance to killing by porcine neutrophils. Taken together, our data demonstrate that CcpA has a significant effect on the capsule synthesis and virulence properties of S. suis.
Fulde, Marcus; Willenborg, Joerg; Huber, Claudia; Hitzmann, Angela; Willms, Daniela; Seitz, Maren; Eisenreich, Wolfgang; Valentin-Weigand, Peter; Goethe, Ralph
The arginine-ornithine antiporter (ArcD) is part of the Arginine Deiminase System (ADS), a catabolic, energy-providing pathway found in a variety of different bacterial species, including the porcine zoonotic pathogen Streptococcus suis. The ADS has recently been shown to play a role in the pathogenicity of S. suis, in particular in its survival in host cells. The contribution of arginine and arginine transport mediated by ArcD, however, has yet to be clarified. In the present study, we showed by experiments using [U-(13)C6]arginine as a tracer molecule that S. suis is auxotrophic for arginine and that bacterial growth depends on the uptake of extracellular arginine. To further study the role of ArcD in arginine metabolism, we generated an arcD-specific mutant strain and characterized its growth compared to the wild-type (WT) strain, a virulent serotype 2 strain. The mutant strain showed a markedly reduced growth in chemically defined media supplemented with arginine when compared to the WT strain, suggesting that ArcD promotes arginine uptake. To further evaluate the in vivo relevance of ArcD, we studied the intracellular bacterial survival of the arcD mutant strain in an epithelial cell culture infection model. The mutant strain was substantially attenuated, and its reduced intracellular survival rate correlated with a lower ability to neutralize the acidified environment. Based on these results, we propose that ArcD, by its function as an arginine-ornithine antiporter, is important for supplying arginine as substrate of the ADS and, thereby, contributes to biological fitness and virulence of S. suis in the host.
Köhler, Stephan; Ouahrani-Bettache, Safia; Layssac, Marion; Teyssier, Jacques; Liautard, Jean-Pierre
A gene fusion system based on plasmid pBBR1MCS and the expression of green fluorescent protein was developed for Brucella suis, allowing isolation of constitutive and inducible genes. Bacteria containing promoter fusions of chromosomal DNA to gfp were visualized by fluorescence microscopy and examined by flow cytometry. Twelve clones containing gene fragments induced inside J774 murine macrophages were isolated and further characterized. PMID:10569794
Köhler, Stephan; Ouahrani-Bettache, Safia; Layssac, Marion; Teyssier, Jacques; Liautard, Jean-Pierre
A gene fusion system based on plasmid pBBR1MCS and the expression of green fluorescent protein was developed for Brucella suis, allowing isolation of constitutive and inducible genes. Bacteria containing promoter fusions of chromosomal DNA to gfp were visualized by fluorescence microscopy and examined by flow cytometry. Twelve clones containing gene fragments induced inside J774 murine macrophages were isolated and further characterized.
Callens, Bénédicte F; Haesebrouck, Freddy; Maes, Dominiek; Butaye, Patrick; Dewulf, Jeroen; Boyen, Filip
Streptococcus suis (S. suis) has often been reported as an important swine pathogen and is considered as a new emerging zoonotic agent. Consequently, it is important to be informed on its susceptibility to antimicrobial agents. In the current study, the Minimum Inhibitory Concentration (MIC) population distribution of nine antimicrobial agents has been determined for nasal S. suis strains, isolated from healthy pigs at the end of the fattening period from 50 closed or semiclosed pig herds. The aim of the study was to report resistance based on both clinical breakpoints (clinical resistance percentage) and epidemiological cutoff values (non-wild-type percentage). Non-wild-type percentages were high for tetracycline (98%), lincomycin (92%), tilmicosin (72%), erythromycin (70%), tylosin (66%), and low for florfenicol (0%) and enrofloxacin (0.3%). Clinical resistance percentages were high for tetracycline (95%), erythromycin (66%), tylosin (66%), and low for florfenicol (0.3%) and enrofloxacin (0.3%). For tiamulin, for which no clinical breakpoint is available, 57% of the isolates did not belong to the wild-type population. Clinical resistance and non-wild-type percentages differed substantially for penicillin. Only 1% of the tested S. suis strains was considered as clinically resistant, whereas 47% of the strains showed acquired resistance when epidemiological cutoff values were used. In conclusion, MIC values for penicillin are gradually increasing, compared to previous reports, although pigs infected with strains showing higher MICs may still respond to treatment with penicillin. The high rate of acquired resistance against tiamulin has not been reported before. Results from this study clearly demonstrate that the use of different interpretive criteria contributes to the extent of differences in reported antimicrobial resistance results. The early detection of small changes in the MIC population distribution of isolates, while clinical failure may not yet be
van Hout, Jobke; Heuvelink, Annet; Gonggrijp, Maaike
The objective of the present study was to analyse the in vitro antimicrobial susceptibility of Streptococcus suis isolates from post-mortem samples from pigs in the Netherlands. S. suis isolates originated from diagnostic submissions of pigs sent to the Pathology Department of GD Animal Health, from April 2013 till June 2015. Minimal inhibitory concentrations (MICs) of in total 15 antimicrobials were assessed by broth microdilution following CLSI recommendations. MIC50 and MIC90 values were determined and MICs were interpreted as susceptible, intermediate and resistant using CLSI veterinary breakpoints (when available). Emergence of resistance among S. suis (n=1163) derived from clinical submissions of pigs appeared to be limited. Resistance to ampicillin, ceftiofur, clindamycin, enrofloxacin, florfenicol, penicillin, trimethoprim/sulfamethoxazole and tetracycline was 0.3%, 0.5%, 48.1%, 0.6%, 0.1%, 0.5%, 3.0%, and 78.4%, respectively. Cross-resistance between penicillin and ampicillin appeared to be incomplete. MIC values of erythromycin, clindamycin, neomycin, penicillin and tilmicosin for isolates originating from grower/finisher pigs were significantly more often lower than the MIC values of isolates from suckling/weaned piglets. It has to be kept in mind that these results represent only part of the Dutch pig population and it can be discussed whether this is a representative sample. Interpretation of the MIC results of (clinically relevant) antimicrobials tested for treatment of S. suis infection is strongly hampered by the lack of CLSI-defined veterinary clinical breakpoints that are animal species- and body site-specific. Therefore, and to conduct a clinically reliable monitoring of antimicrobial susceptibility of veterinary pathogens, more species- and organ-specific veterinary breakpoints are urgently needed.
Due to the age and operating experience of Bruce Power units, equipment ageing and obsolescence has become one of the main challenges that need to be resolved for all systems, structures and components in order to ensure a safe and reliable production of energy. The research objectives of this thesis will focus on methodology for modernization of Start-Up Instrumentation (SUI), both in-core and Control Room equipment, using a new generation of detectors and cables in order to manage obsolescence. The main objective of this thesis is to develop a new systematic approach to SUI installation/replacement procedure development and optimization. Although some additional features, such as real-time data monitoring and storage/archiving solutions for SUI systems are also examined to take full advantage of today's digital technology, the objective of this thesis does not include detailed parametrical studies of detector or system performance. Instead, a number of technological, operational and maintenance issues associated with Start-Up Instrumentation systems at Bruce Power will be identified in this project and a structured approach to developing a replacement/installation procedure that can be standardized and used across all of the domestic CANDU stations is proposed. Finally, benefits of Hierarchical Control Chart (HCC) methodology for all stages of plant life management, such as system design, development, operation and maintenance are demonstrated. Keywords: Task Breakdown and Analysis methodology, installation/removal procedure development and optimization, risk-based analysis and optimization, Hierarchical Control Chart (HCC) methodology for system maintenance and troubleshooting, Start-Up Instrumentation (SUI), Ion Chambers, Fission Chambers, proportional counters, Shutdown System 1 (SDS1), Shutdown System 2 (SDS2).
Fabrizio De Massis
Full Text Available Un cinghiale selvatico femmina, di circa due anni di età, è stato trovato morto dai Servizi Veterinari a Pianola di Roio a L'Aquila, Provincia situata nella Regione Abruzzo nell'Italia centrale. La carcassa è stata conferita all'Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise "G. Caporale" di Teramo per l'esecuzione dell'esame autoptico. Dai linfonodi sotto-mandibolari di questo esemplare è stato isolato un ceppo di Brucella suis biovariante 2. Questa è la prima segnalazione d'isolamento di B. suis nella Regione Abruzzo. Diversi autori hanno accettato, in passato, l'ipotesi che B. suis biovariante 2 sia stata introdotta in Italia attraverso l'importazione di lepri provenienti dai paesi europei in cui l'infezione è endemica nelle popolazioni selvatiche. Questa considerazione ha portato le autorità italiane a rafforzare i controlli esistenti sulle lepri selvatiche importate a scopo di ripopolamento. Tuttavia, attualmente, non è in vigore alcuna disposizione (né lo è stata in passato per il controllo della brucellosi nei cinghiali movimentati, sia a livello nazionale che europeo. L'isolamento di B. suis biovariante 2 da cinghiali in altre Regioni italiane geograficamente distanti potrebbe suggerire che questa specie, piuttosto che le lepri importate, possa essere stata la fonte d'introduzione dell'infezione in tali aree. Le norme nazionali ed europee di gestione della brucellosi nella fauna selvatica dovrebbero essere indirizzate al controllo dello stato di salute dei cinghiali negli allevamenti prima delle movimentazioni o del rilascio, con l'obiettivo di prevenire la diffusione di questo patogeno in territori indenni.
Full Text Available The arginine-ornithine antiporter (ArcD is part of the Arginine Deiminase System (ADS, a catabolic, energy-providing pathway found in a variety of different bacterial species, including the porcine zoonotic pathogen Streptococcus suis. The ADS has recently been shown to play a role in the pathogenicity of S. suis, in particular in its survival in host cells. The contribution of arginine and arginine transport mediated by ArcD, however, has yet to be clarified. In the present study, we showed by experiments using [U-13C6]arginine as a tracer molecule that S. suis is auxotrophic for arginine and that bacterial growth depends on the uptake of extracellular arginine. To further study the role of ArcD in arginine metabolism, we generated an arcD-specific mutant strain and characterized its growth compared to the wild-type (WT strain, a virulent serotype 2 strain. The mutant strain showed a markedly reduced growth rate in chemically defined media supplemented with arginine when compared to the WT strain, indicating that ArcD promotes arginine uptake. To further evaluate the in vivo relevance of ArcD, we studied the intracellular bacterial survival of the arcD mutant strain in an epithelial cell culture infection model. The mutant strain was substantially attenuated, and its reduced intracellular survival rate correlated with a lower ability to neutralize the acidified environment. Based on these results, we propose that ArcD, by its function as an arginine-ornithine antiporter, is important for supplying arginine as substrate of the ADS and, thereby, contributes to biological fitness and virulence of S. suis in the host.
Zhao, Wenqiang; Liu, Xing; Huang, Qiaoyun; Cai, Peng
Understanding pathogen sorption on natural soil particles is crucial to protect public health from soilborne and waterborne diseases. Sorption of pathogen Streptococcus suis on 10 agricultural soils was examined, and its correlations with soil physico-chemical properties were also elucidated. S. suis sorption isotherms conformed to the linear equation, with partition coefficients (Ks) ranging from 12.7 mL g(-1) to 100.1 mL g(-1). Bacteria were observed to sorb on the external surfaces of soil aggregates by scanning electron microscopy. Using Pearson correlation and linear regression analysis, solution pH was found to have significant negative correlations with Ks. Stepwise multiple regression and path analysis revealed that pH and cation exchange capacity (CEC) were the main factors influencing sorption behaviors. The obtained overall model (Ks=389.6-45.9×pH-1.3×CEC, R(2)=0.943, PKs values. However, the variability in Ks was less dependent on soil organic matter, specific surface area, soil texture and zeta potential, probably due to the internal-surface shielding phenomenon of soil aggregates. Additionally, the sorption trends cannot be interpreted by interaction energy barriers calculated using the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory, suggesting the limits of DLVO theory in describing pathogen sorption on natural soils. Our results also indicated soil pH and CEC should be preferentially considered when modeling S. suis sorption process.
Naroeni, Aroem; Jouy, Nicolas; Ouahrani-Bettache, Safia; Liautard, Jean-Pierre; Porte, Françoise
Brucella species are gram-negative, facultatively intracellular bacteria that infect humans and animals. These organisms can survive and replicate within a membrane-bound compartment in phagocytic and nonprofessional phagocytic cells. Inhibition of phagosome-lysosome fusion has been proposed as a mechanism for intracellular survival in both types of cells. However, the biochemical mechanisms and microbial factors implicated in Brucella maturation are still completely unknown. We developed two different approaches in an attempt to gain further insight into these mechanisms: (i) a fluorescence microscopy analysis of general intracellular trafficking on whole cells in the presence of Brucella and (ii) a flow cytometry analysis of in vitro reconstitution assays showing the interaction between Brucella suis-containing phagosomes and lysosomes. The fluorescence microscopy results revealed that fusion properties of latex bead-containing phagosomes with lysosomes were not modified in the presence of live Brucella suis in the cells. We concluded that fusion inhibition was restricted to the pathogen phagosome and that the host cell fusion machinery was not altered by the presence of live Brucella in the cell. By in vitro reconstitution experiments, we observed a specific association between killed B. suis-containing phagosomes and lysosomes, which was dependent on exogenously supplied cytosol, energy, and temperature. This association was observed with killed bacteria but not with live bacteria. Hence, this specific recognition inhibition seemed to be restricted to the pathogen phagosomal membrane, as noted in the in vivo experiments. PMID:11119541
Ferrando, Maria Laura; Willemse, Niels; Zaccaria, Edoardo; Pannekoek, Yvonne; van der Ende, Arie; Schultsz, Constance
Background Streptococcus suis is a zoonotic pathogen, causing meningitis and septicemia. We previously demonstrated that the gastrointestinal tract (GIT) is an entry site for zoonotic S. suis infection. Here we studied the contribution of Streptococcal adhesin Protein (SadP) to host-pathogen interaction at GIT level. Methods SadP expression in presence of Intestinal Epithelial Cells (IEC) was compared with expression of other virulence factors by measuring transcript levels using quantitative Real Time PCR (qRT-PCR). SadP variants were identified by phylogenetic analysis of complete DNA sequences. The interaction of SadP knockout and complementation mutants with IEC was tested in vitro. Results Expression of sadP was significantly increased in presence of IEC. Sequence analysis of 116 invasive strains revealed five SadP sequence variants, correlating with genotype. SadP1, present in zoonotic isolates of clonal complex 1, contributed to binding to both human and porcine IEC and translocation across human IEC. Antibodies against the globotriaosylceramide Gb3/CD77 receptor significantly inhibited adhesion to human IEC. Conclusion SadP is involved in the host-pathogen interaction in the GIT. Differences between SadP variants may determine different affinities to the Gb3/CD77 host-receptor, contributing to variation in adhesion capacity to host IEC and thus to S. suis zoonotic potential. PMID:28407026
Hansen, Eline Palm; Kringel, Helene; Williams, Andrew R; Nejsum, Peter
Trichuris suis is a common parasitic helminth of pigs. As with many other parasites, T. suis ensures its own survival by evading host immune responses, but little is known about how this is achieved. MicroRNAs (miRNA) have been shown to be involved in various immunological processes by post-transcriptional regulation of specific genes, and the potential of using these molecules as biomarkers of disease is currently being examined. It has recently been shown that parasites may secrete extracellular structures such as exosomes and microvesicles, containing proteins and miRNA. The fusion of these structures with host cells has been demonstrated, and a role of exosome-derived miRNA in host gene regulation has been suggested. In the present study, we show that exosome- and microvesicular-like structures are secreted by T. suis L1 larvae and also demonstrate the presence of miRNA-sized RNA inside these structures. A potential role of these molecules in host-parasite interactions is suggested. In addition, an electron-dense layer covering the surface of the larvae was observed, which may play a function in host immune evasion.
Full Text Available Streptococcus suis serotype 2 (SS2 is a zoonotic pathogen that can cause infections in pigs and humans. Bacterial surface proteins are often investigated as potential vaccine candidates and biomarkers of virulence. In this study, a novel method for identifying bacterial surface proteins is presented, which combines immunoproteomic and immunoserologic techniques. Critical to the success of this new method is an improved procedure for generating two-dimensional electrophoresis gel profiles of S. suis proteins. The S. suis surface proteins identified in this study include muramidase-released protein precursor (MRP and an ABC transporter protein, while MRP is thought to be one of the main virulence factors in SS2 located on the bacterial surface. Herein, we demonstrate that the ABC transporter protein can bind to HEp-2 cells, which strongly suggests that this protein is located on the bacterial cell surface and may be involved in pathogenesis. An immunofluorescence assay confirmed that the ABC transporter is localized to the bacterial outer surface. This new method may prove to be a useful tool for identifying surface proteins, and aid in the development of new vaccine subunits and disease diagnostics.
Czibener, Cecilia; Del Giudice, Mariela Giselda; Spera, Juan Manuel; Fulgenzi, Fabiana Rosa; Ugalde, Juan Esteban
Brucellosis is one of the most widespread zoonosis in the world affecting many domestic and wild animals including bovines, goats, pigs and dogs. Each species of the Brucella genus has a particular tropism toward different mammals being the most relevant for human health Brucella abortus, Brucella melitensis and Brucella suis that infect bovines, goats/camelids and swine respectively. Although for B. abortus and B. melitensis there are vaccines available, there is no efficient vaccine to protect swine from B. suis infection so far. We describe here the construction of a novel vaccine strain that confers excellent protection against B. suis in a mouse model of infection. This strain is a clean deletion of the phosphoglucomutase (pgm) gene that codes for a protein that catalyzes the conversion of glucose-6-P to glucose-1-P, which is used as a precursor for the biosynthesis of many polysaccharides. The Delta-pgm strain lacks a complete lipopolysaccharide, is unable to synthesize cyclic beta glucans and is sensitive to several detergents and Polymyxin B. We show that this strain replicates in cultured cells, is completely avirulent in the mouse model of infection but protects against a challenge of the virulent strain inducing the production of pro-inflammatory cytokines. This novel strain could be an excellent candidate for the control of swine brucellosis, a disease of emerging concern in many parts of the world.
Huong, Vu Thi Lan; Ha, Ngo; Huy, Nguyen Tien; Horby, Peter; Nghia, Ho Dang Trung; Thiem, Vu Dinh; Zhu, Xiaotong; Hoa, Ngo Thi; Hien, Tran Tinh; Zamora, Javier; Schultsz, Constance; Wertheim, Heiman Frank Louis; Hirayama, Kenji
Streptococcus suis, a bacterium that affects pigs, is a neglected pathogen that causes systemic disease in humans. We conducted a systematic review and meta-analysis to summarize global estimates of the epidemiology, clinical characteristics, and outcomes of this zoonosis. We searched main literature databases for all studies through December 2012 using the search term "streptococcus suis." The prevalence of S. suis infection is highest in Asia; the primary risk factors are occupational exposure and eating of contaminated food. The pooled proportions of case-patients with pig-related occupations and history of eating high-risk food were 38.1% and 37.3%, respectively. The main clinical syndrome was meningitis (pooled rate 68.0%), followed by sepsis, arthritis, endocarditis, and endophthalmitis. The pooled case-fatality rate was 12.8%. Sequelae included hearing loss (39.1%) and vestibular dysfunction (22.7%). Our analysis identified gaps in the literature, particularly in assessing risk factors and sequelae of this infection.
Hutchinson, Rachel; Gibson, Wendy
The African tsetse-transmitted trypanosomes are considered to be a well-known group of parasitic protozoa, but in 2008 a novel and distinctive trypanosome related to Trypanosoma brucei was discovered among tsetse isolates from Msubugwe in Tanzania. The host range, distribution and potential pathogenicity of this new trypanosome remain to be elucidated; such studies would be facilitated by a sensitive and specific identification method. Here, we identified two highly repetitive elements in the genome of the new trypanosome: a 177 bp repeat, which was located predominantly on the highly abundant minichromosomes, and a 138 bp repeat, which was widely dispersed in the genome. A PCR test based on each repeat was specific for the new trypanosome and sensitive to Trypanosoma (Pycnomonas) suis. We also present data on the molecular karyotype and spliced leader (SL, miniexon) repeat of the new trypanosome, both of which distinguish T. suis from other, better-known African tsetse-transmitted trypanosomes. The rediscovery of T. suis opens new lines of research into the evolution and biology of the African trypanosomes.
De Clercq, Evelien; Devriendt, Bert; Yin, Lizi; Chiers, Koen; Cox, Eric; Vanrompay, Daisy
The aim of the present study was to reveal the characteristic features of genital Chlamydia suis infection and re-infection in female pigs by studying the immune response, pathological changes, replication of chlamydial bacteria in the genital tract and excretion of viable bacteria. Pigs were intravaginally infected and re-infected with C. suis strain S45, the type strain of this species. We demonstrated that S45 is pathogenic for the female urogenital tract. Chlamydia replication occurred throughout the urogenital tract, causing inflammation and pathology. Furthermore, genital infection elicited both cellular and humoral immune responses. Compared to the primo-infection of pigs with C. suis, re-infection was characterized by less severe macroscopic lesions and less chlamydial elementary bodies and inclusions in the urogenital tract. This indicates the development of a certain level of protection following the initial infection. Protective immunity against re-infection coincided with higher Chlamydia-specific IgG and IgA antibody titers in sera and vaginal secretions, higher proliferative responses of peripheral blood mononuclear cells (PBMC), higher percentages of blood B lymphocytes, monocytes and CD8⁺ T cells and upregulated production of IFN-γ and IL-10 by PBMC.
Huong, V T L; Thanh, L V; Phu, V D; Trinh, D T; Inui, K; Tung, N; Oanh, N T K; Trung, N V; Hoa, N T; Bryant, J E; Horby, P W; Kinh, N V; Wertheim, H F L
Porcine reproductive and respiratory syndrome (PRRS) outbreaks in pigs are associated with increased susceptibility of pigs to secondary bacterial infections, including Streptococcus suis - an important zoonotic pathogen causing bacterial meningitis in humans. This case-control study examined the association between human S. suis infection and PRRS outbreaks in pigs in northern Vietnam. We included 90 S. suis case-patients and 183 non-S. suis sepsis controls from a referral hospital in Hanoi in 2010, a period of major PRRS epizootics in Vietnam. PRRS exposure was determined using data from the National Centre of Veterinary Diagnosis. By univariate analysis, significantly more S. suis patients were reported residing in or adjacent to a PRRS district compared to controls [odds ratio (OR) 2·82, 95% confidence interval (CI) 1·35-5·89 and OR 3·15, 95% CI 1·62-6·15, respectively]. Only residency in adjacent districts remained significantly associated with risk of S. suis infection after adjusting for sex, occupation, and eating practices. SaTScan analysis showed a possible cluster of S. suis infection in humans around PRRS confirmed locations during the March-August period. The findings indicate an epidemiological association between PRRS in pigs and S. suis infections in humans. Effective strategies to strengthen control of PRRS in pigs may help reduce transmission of S. suis infection to humans.
Low occurrence of 'non-haemolytic Haemophilus haemolyticus' misidentified as Haemophilus influenzae in cystic fibrosis respiratory specimens, and frequent recurrence of persistent H. influenzae clones despite antimicrobial treatment.
Fenger, Mette G; Ridderberg, Winnie; Olesen, Hanne V; Nørskov-Lauritsen, Niels
Non-influenzae commensal Haemophilus species of low pathogenicity may be difficult to discriminate from Haemophilus influenzae. We investigated the level of misidentifications in respiratory specimens from cystic fibrosis patients and evaluated the colonisation dynamics of genuine H. influenzae isolates. One hundred and ninety-two presumptive H. influenzae isolates were re-examined by assessment of marker genes sodC and fucK, and isolates with aberrant genotypes were subjected to multilocus sequence typing. Misidentifications (3%) were mainly caused by failure to identify porphyrin-synthesising strains, and only a single strain (0.5%) could be classified as 'non-haemolytic Haemophilus haemolyticus'. Sequential isolates of confirmed H. influenzae isolates from individual patients were typed by pulsed-field gel electrophoresis. Despite the routine prescription of antimicrobial therapy, the majority of H. influenzae isolates were identical with at least one of the strains cultured from the two preceding positive samples from the same patient.
Nawrocki, Erin M; Bedell, Hillary W; Humphreys, Tricia L
Resveratrol, a polyphenolic phytoalexin, is produced by plants in response to infection and has antibacterial activity. Haemophilus ducreyi is a Gram-negative bacterium that is the causative agent of the sexually transmitted disease chancroid. This study employed minimum cidal concentration (MCC) assays to evaluate the potential of resveratrol as a microbicide against H. ducreyi. Five class I and four class II strains of H. ducreyi tested had MCCs ≤500 μg/mL. Resveratrol was also tested against Lactobacillus spp., part of the natural vaginal flora. Representative strains of Lactobacillus were co-cultured with H. ducreyi and 500 μg/mL resveratrol; in all cases, Lactobacillus was recovered in greater numbers than H. ducreyi. These results show that resveratrol is not only bacteriostatic but is bactericidal to H. ducreyi, confirming the compound's potential for use as a topical microbicide to prevent chancroid.
Strouts, Fiona R; Power, Peter; Croucher, Nicholas J; Corton, Nicola; van Tonder, Andries; Quail, Michael A; Langford, Paul R; Hudson, Michael J; Parkhill, Julian; Kroll, J Simon; Bentley, Stephen D
An emergent clone of Haemophilus influenzae biogroup aegyptius (Hae) is responsible for outbreaks of Brazilian purpuric fever (BPF). First recorded in Brazil in 1984, the so-called BPF clone of Hae caused a fulminant disease that started with conjunctivitis but developed into septicemic shock; mortality rates were as high as 70%. To identify virulence determinants, we conducted a pan-genomic analysis. Sequencing of the genomes of the BPF clone strain F3031 and a noninvasive conjunctivitis strain, F3047, and comparison of these sequences with 5 other complete H. influenzae genomes showed that >77% of the F3031 genome is shared among all H. influenzae strains. Delineation of the Hae accessory genome enabled characterization of 163 predicted protein-coding genes; identified differences in established autotransporter adhesins; and revealed a suite of novel adhesins unique to Hae, including novel trimeric autotransporter adhesins and 4 new fimbrial operons. These novel adhesins might play a critical role in host-pathogen interactions.
Fatma Deniz Aygun
Full Text Available Haemophilus influenza is one of the most common cause of bacterial meningitis in children. H.influenzae, especially type b (Hib serotype causes invasive infections in children under five years of age. The widespread use of Hib conjugate vaccines has led to a dramatic decline in the incidence of invasive Hib infections. But, the invasive diseases are still reported, particularly nontypeable H. influenzae (noncapsulated remain as an important pathogen. However, there is no evidence that nontypeable H. influenzae infections have increased in frequency. Nontypeable H. Influenzae serotype is encountered as a cause of acute bacterial meningitis among all ages. In this paper, we present to draw attention to the causative bacterium, in a case of bacterial meningitis caused by nontypeable H. influenzae infection in a child immunized with Hib vaccine.
Olga C Aulet de Saab
Full Text Available The aim of this study was to compare the efficacy of conservation by freezing the strains of Haemophilus influenzae at -20ºC and -70ºC. Skim milk supplemented with glucose, yeast extract and glycerol allowed highest viability of H. influenzae both at -20ºC and -70ºC from the media analyzed. Trypticase soy broth and brain heart infusion broth supplemented with glycerol, allowed excellent recovery. Use of cotton swaps as supporting material, with or without addition of cryoprotective agents, did not modify H. influenzae viability after six months of storage. Concentration of the initial inoculum positively affected viability when stored at -20ºC. Initial concentration did not influence survival after storage at -70ºC. Thawing at room temperature should not exceed 3 h as to get highest survival percentage.
Barnhart, B.J.; Cox, S.H.; Jett, J.H.
Analysis of the induction curves for uv light-irradiated Haemophilus influenzae lysogens and the distribution of pyrimidine dimers in a repair-deficient lysogen suggests that one dimer per prophage-size segment of the host bacterial chromosome is necessary as a preinduction event. The close correlations obtained prompted a renewed consideration of the possibility that direct prophage induction occurs when one dimer is stabilized within the prophage genome. The host excision-repair system apparently functions to reduce the probability of stabilizing within the prophage those dimers that are necessary for induction and inactivation. The presence of the inducible defective prophage in strain Rd depresses the inducibility of prophage HP1c1.
Notani, N.K.; Setlow, J.K.; McCarthy, D.; Clayton, N.L.
Plasmid RSF0885, which conferred ampicillin resistance, transformed competent Haemophilus influenzae cells with low efficiency (maximun, less than 0.01%). As judged by competition experiments and uptake of radioactivity, plasmid RSF0885 deoxyribonucleic acid was taken up into competent H. influenzae cells several orders of magnitude less efficiently than H. influenzae chromosomal deoxyribonucleic acid. Plasmid RSF0885 transformed cells with even lower efficiency than could be accounted for by the low uptake. Transformation was not affected by rec-1 and rec-2 mutations in the recipient, and strains cured of the plasmid did not show increased transformation. Plasmid molecules cut once with a restriction enzyme that made blunt ends did not transform. Transformation was favored by the closed circular form of the plasmid.
Janessa Lea Pickering
Full Text Available Nontypeable Haemophilus influenzae (NTHi is an opportunistic pathogen that resides in the upper respiratory tract and contributes to a significant burden of respiratory related diseases in children and adults. Haemophilus haemolyticus is a respiratory tract commensal that can be misidentified as NTHi due to high levels of genetic relatedness. There are reports of invasive disease from H. haemolyticus, which further blurs the species boundary with NTHi. To investigate differences in pathogenicity between these species, we optimized an in vitro epithelial cell model to compare the interaction of 10 H. haemolyticus strains with 4 NTHi and 4 H. influenzae-like haemophili. There was inter- and intra-strain variability but overall, H. haemolyticus had reduced capacity to attach to and invade nasopharyngeal and bronchoalveolar epithelial cell lines (D562 and A549 within 3h when compared with NTHi. H. haemolyticus was cytotoxic to both cell lines at 24h, whereas NTHi was not. Nasopharyngeal epithelium challenged with some H. haemolyticus strains released high levels of inflammatory mediators IL-6 and IL-8, whereas NTHi did not elicit an inflammatory response despite higher levels of cell association and invasion. Furthermore, peripheral blood mononuclear cells stimulated with H. haemolyticus or NTHi released similar and high levels of IL-6, IL-8, IL-10, IL-1β and TNFα when compared with unstimulated cells but only NTHi elicited an IFNγ response.Due to the relatedness of H. haemolyticus and NTHi, we hypothesized that H. haemolyticus may compete with NTHi for colonization of the respiratory tract. We observed that in vitro pre-treatment of epithelial cells with H. haemolyticus significantly reduced NTHi attachment, suggesting interference or competition between the two species is possible and warrants further investigation. In conclusion, H. haemolyticus interacts differently with host cells compared to NTHi, with different immunostimulatory and
Angen, Øystein; Ahrens, Peter; Kuhnert, P.
Earlier investigations have shown that 'Haemophilus somnus','Haemophilus agni' and' Histophilus ovis' represent the same species. In the present investigation, the taxonomic position of this species is explored further by sequencing the 16S rRNA and rpoB genes of strains that were investigated pr...... similarity to any other taxon within the family is 93.4%. The type strain, 8025(T) = ATCC 43625(T) CCUG 36157(T), was isolated in the USA from a bovine brain with lesions of thromboembolic meningoencephalitis....
Benga, L; Goethe, R; Rohde, M; Valentin-Weigand, P
Streptococcus suis is a porcine and human pathogen causing invasive diseases, such as meningitis or septicaemia. Host cell interactions of S. suis have been studied mainly with serotype 2 strains, but multiple capsular serotypes as well as non-typeable strains exist with diverse virulence features. At present, S. suis is considered an extracellular pathogen. However, whether or not it can also invade host cells is a matter of controversial discussions. We have assessed adherence and invasion of S. suis for HEp-2 epithelial cells by comparing 10 serotype 2 strains and four non-typeable (NT) strains. Only the NT strains and a non-encapsulated serotype 2 mutant strain, but none of the serotype 2 strains, adhered strongly and were invasive. Invasion seemed to be affected by environmental signals, as suggested from comparison of strains grown in different media. Further phenotypic and genotypic characterization revealed a high diversity among the different strains. Electron microscopic analysis of invasion of selected invasive NT strains indicated different uptake mechanisms. One strain induced large invaginations comparable to those seen in 'caveolae' mediated uptake, whereas invasion of the other strains was accompanied by formation of filipodia-like membrane protrusions. Invasion of all strains, however, was similarly susceptible to hypertonic sucrose, which inhibits receptor-mediated endocytosis. Irrespective of the uptake pathway, streptococci resided in acidified phago-lysosome like vacuoles. All strains, except one, survived intracellularly as well as extracellular acidic conditions. Survival seemed to be associated with the AdiS protein, an environmentally regulated arginine deiminase of S. suis. Concluding, invasion and survival of NT strains of S. suis in epithelial cells revealed novel evidence that S. suis exhibits a broad variety of virulence-associated features depending on genetic variation and regulation.
Bosschem, Iris; Bayry, Jagadeesh; De Bruyne, Ellen; Van Deun, Kim; Smet, Annemieke; Vercauteren, Griet; Ducatelle, Richard; Haesebrouck, Freddy; Flahou, Bram
Helicobacter suis (H. suis) is a widespread porcine gastric pathogen, which is also of zoonotic importance. The first goal of this study was to investigate the efficacy of several vaccine adjuvants (CpG-DNA, Curdlan, Freund's Complete and Incomplete, Cholera toxin), administered either subcutaneously or intranasally along with H. suis whole-cell lysate, to protect against subsequent H. suis challenge in a BALB/c infection model. Subcutaneous immunization with Freund's complete (FC)/lysate and intranasal immunization with Cholera toxin (CT)/lysate were shown to be the best options for vaccination against H. suis, as determined by the amount of colonizing H. suis bacteria in the stomach, although adverse effects such as post-immunization gastritis/pseudo-pyloric metaplasia and increased mortality were observed, respectively. Therefore, we decided to test alternative strategies, including sublingual vaccine administration, to reduce the unwanted side-effects. A CCR4 antagonist that transiently inhibits the migration of regulatory T cells was also included as a new adjuvant in this second study. Results confirmed that immunization with CT (intranasally or sublingually) is among the most effective vaccination protocols, but increased mortality was still observed. In the groups immunized subcutaneously with FC/lysate and CCR4 antagonist/lysate, a significant protection was observed. Compared to the FC/lysate immunized group, gastric pseudo-pyloric metaplasia was less severe or even absent in the CCR4 antagonist/lysate immunized group. In general, an inverse correlation was observed between IFN-γ, IL-4, IL-17, KC, MIP-2 and LIX mRNA expression and H. suis colonization density, whereas lower IL-10 expression levels were observed in partially protected animals.
Thi Hoa Ngo
Full Text Available Streptococcus suis is a pathogen of major economic significance to the swine industry and is increasingly recognized as an emerging zoonotic agent in Asia. In Vietnam, S. suis is the leading cause of bacterial meningitis in adult humans. Zoonotic transmission is most frequently associated with serotype 2 strains and occupational exposure to pigs or consumption of infected pork. To gain insight into the role of pigs for human consumption as a reservoir for zoonotic infection in southern Vietnam, we determined the prevalence and diversity of S. suis carriage in healthy slaughterhouse pigs. Nasopharyngeal tonsils were sampled from pigs at slaughterhouses serving six provinces in southern Vietnam and Ho Chi Minh City area from September 2006 to November 2007. Samples were screened by bacterial culture. Isolates of S. suis were serotyped and characterized by multi locus sequence typing (MLST and pulse field gel electrophoresis (PFGE. Antibiotic susceptibility profiles and associated genetic resistance determinants, and the presence of putative virulence factors were determined. 41% (222/542 of pigs carried S. suis of one or multiple serotypes. 8% (45/542 carried S. suis serotype 2 which was the most common serotype found (45/317 strains, 14%. 80% of serotype 2 strains belonged to the MLST clonal complex 1,which was previously associated with meningitis cases in Vietnam and outbreaks of severe disease in China in 1998 and 2005. These strains clustered with representative strains isolated from patients with meningitis in PFGE analysis, and showed similar antimicrobial resistance and virulence factor profiles. Slaughterhouse pigs are a major reservoir of S. suis serotype 2 capable of causing human infection in southern Vietnam. Strict hygiene at processing facilities, and health education programs addressing food safety and proper handling of pork should be encouraged.
Full Text Available Helicobacter suis (H. suis is a widespread porcine gastric pathogen, which is also of zoonotic importance. The first goal of this study was to investigate the efficacy of several vaccine adjuvants (CpG-DNA, Curdlan, Freund's Complete and Incomplete, Cholera toxin, administered either subcutaneously or intranasally along with H. suis whole-cell lysate, to protect against subsequent H. suis challenge in a BALB/c infection model. Subcutaneous immunization with Freund's complete (FC/lysate and intranasal immunization with Cholera toxin (CT/lysate were shown to be the best options for vaccination against H. suis, as determined by the amount of colonizing H. suis bacteria in the stomach, although adverse effects such as post-immunization gastritis/pseudo-pyloric metaplasia and increased mortality were observed, respectively. Therefore, we decided to test alternative strategies, including sublingual vaccine administration, to reduce the unwanted side-effects. A CCR4 antagonist that transiently inhibits the migration of regulatory T cells was also included as a new adjuvant in this second study. Results confirmed that immunization with CT (intranasally or sublingually is among the most effective vaccination protocols, but increased mortality was still observed. In the groups immunized subcutaneously with FC/lysate and CCR4 antagonist/lysate, a significant protection was observed. Compared to the FC/lysate immunized group, gastric pseudo-pyloric metaplasia was less severe or even absent in the CCR4 antagonist/lysate immunized group. In general, an inverse correlation was observed between IFN-γ, IL-4, IL-17, KC, MIP-2 and LIX mRNA expression and H. suis colonization density, whereas lower IL-10 expression levels were observed in partially protected animals.
Nielsen, Ragnhild; van den Bosch, Johannes F.; Plambeck, Tamara
The reference strains of the 12 serotypes of Actinobacillus pleuropneumoniae express one or two of three different RTX exotoxins designated Apr I, Apr II and Apr III. The toxins are important virulence factors. In the present study, ELISAs with purified Apr I, Apr II and Apr III, respectively......, as antigen were evaluated as candidates for serological diagnosis of Actinobacillus pleuropneumoniae infection in pigs, The pigs were inoculated with biotype 1, serotypes 1-12, and biotype 2, serotype 14, respectively. A strong humoral antibody response was seen to all the three antigens in most pigs...... irrespective of the serotype used for inoculation. However, titers to the exotoxins secreted by the serotype used for inoculation were generally highest. The results show that toxin proteins of Actinobacillus pleuropneumoniae line are antigenically related and that a correlation between serotype and secretion...
Full Text Available The gram-negative bacterium Actinobacillus pleuropneumoniae (APP is an inhabitant of the porcine upper respiratory tract and the causative agent of porcine pleuropneumonia (PP. In recent years, knowledge about the proinflammatory cytokine and chemokine gene expression that occurs in lung and lymph node of the APP-infected swine has been advanced. However, systematic gene expression profiles on hilar nodes from pigs after infection with Actinobacillus pleuropneumoniae have not yet been reported. The transcriptional responses were studied in hilar nodes (HN from swine experimentally infected with APP and the control groupusing Agilent Porcine Genechip, including 43,603 probe sets. 9,517 transcripts were identified as differentially expressed (DE at the p ≤ 0.01 level by comparing the log2 (normalized signal of the two groups named treatment group (TG and controls (CG. Eight hundred and fifteen of these DE transcripts were annotated as pig genes in the GenBank database (DB. Two hundred and seventy-two biological process categories (BP, 75 cellular components and 171 molecular functions were substantially altered in the TG compared to CG. Many BP were involved in host immune responses (i.e., signaling, signal transmission, signal transduction, response to stimulus, oxidation reduction, response to stress, immune system process, signaling pathway, immune response, cell surface receptor linked signaling pathway. Seven DE gene pathways (VEGF signaling pathway, Long-term potentiation, Ribosome, Asthma, Allograft rejection, Type I diabetes mellitus and Cardiac muscle contraction and statistically significant associations with host responses were affected. Many cytokines (including NRAS, PI3K, MAPK14, CaM, HSP27, protein phosphatase 3, catalytic subunit and alpha isoform, mediating the proliferation and migration of endothelial cells and promoting survival and vascular permeability, were activated in TG, whilst many immunomodulatory cytokines were
Yu, Shumin; Zuo, Zhicai; Cui, Hengmin; Li, Mingzhou; Peng, Xi; Zhu, Ling; Zhang, Ming; Li, Xuewei; Xu, Zhiwen; Gan, Meng; Deng, Junliang; Fang, Jing; Ma, Jideng; Su, Shengqun; Wang, Ya; Shen, Liuhong; Ma, Xiaoping; Ren, Zhihua; Wu, Bangyuan; Hu, Yanchun
The gram-negative bacterium Actinobacillus pleuropneumoniae (APP) is an inhabitant of the porcine upper respiratory tract and the causative agent of porcine pleuropneumonia (PP). In recent years, knowledge about the proinflammatory cytokine and chemokine gene expression that occurs in lung and lymph node of the APP-infected swine has been advanced. However, systematic gene expression profiles on hilar nodes from pigs after infection with Actinobacillus pleuropneumoniae have not yet been reported. The transcriptional responses were studied in hilar nodes (HN) from swine experimentally infected with APP and the control groupusing Agilent Porcine Genechip, including 43,603 probe sets. 9,517 transcripts were identified as differentially expressed (DE) at the p ≤ 0.01 level by comparing the log2 (normalized signal) of the two groups named treatment group (TG) and controls (CG). Eight hundred and fifteen of these DE transcripts were annotated as pig genes in the GenBank database (DB). Two hundred and seventy-two biological process categories (BP), 75 cellular components and 171 molecular functions were substantially altered in the TG compared to CG. Many BP were involved in host immune responses (i.e., signaling, signal transmission, signal transduction, response to stimulus, oxidation reduction, response to stress, immune system process, signaling pathway, immune response, cell surface receptor linked signaling pathway). Seven DE gene pathways (VEGF signaling pathway, Long-term potentiation, Ribosome, Asthma, Allograft rejection, Type I diabetes mellitus and Cardiac muscle contraction) and statistically significant associations with host responses were affected. Many cytokines (including NRAS, PI3K, MAPK14, CaM, HSP27, protein phosphatase 3, catalytic subunit and alpha isoform), mediating the proliferation and migration of endothelial cells and promoting survival and vascular permeability, were activated in TG, whilst many immunomodulatory cytokines were suppressed
Background Succinic acid is a building-block chemical which could be used as the precursor of many industrial products. The dissolved CO2 concentration in the fermentation broth could strongly regulate the metabolic flux of carbon and the activity of phosphoenolpyruvate (PEP) carboxykinase, which are the important committed steps for the biosynthesis of succinic acid by Actinobacillus succinogenes. Previous reports showed that succinic acid production could be promoted by regulating the supply of CO2 donor in the fermentation broth. Therefore, the effects of dissolved CO2 concentration and MgCO3 on the fermentation process should be investigated. In this article, we studied the impacts of gaseous CO2 partial pressure, dissolved CO2 concentration, and the addition amount of MgCO3 on succinic acid production by Actinobacillus succinogenes ATCC 55618. We also demonstrated that gaseous CO2 could be removed when MgCO3 was fully supplied. Results An effective CO2 quantitative mathematical model was developed to calculate the dissolved CO2 concentration in the fermentation broth. The highest succinic acid production of 61.92 g/L was obtained at 159.22 mM dissolved CO2 concentration, which was supplied by 40 g/L MgCO3 at the CO2 partial pressure of 101.33 kPa. When MgCO3 was used as the only CO2 donor, a maximal succinic acid production of 56.1 g/L was obtained, which was just decreased by 7.03% compared with that obtained under the supply of gaseous CO2 and MgCO3. Conclusions Besides the high dissolved CO2 concentration, the excessive addition of MgCO3 was beneficial to promote the succinic acid synthesis. This was the first report investigating the replaceable of gaseous CO2 in the fermentation of succinic acid. The results obtained in this study may be useful for reducing the cost of succinic acid fermentation process. PMID:22040346
Hariadi, Nurul I; Zhang, Lixin; Patel, Mayuri; Sandstedt, Sara A; Davis, Gregg S; Marrs, Carl F; Gilsdorf, Janet R
Nontypeable Haemophilus influenzae (NTHI) are Gram-negative bacteria that colonize the human pharynx and can cause respiratory tract infections, such as acute otitis media (AOM). Since NTHI require iron from their hosts for aerobic growth, the heme acquisition genes may play a significant role in avoiding host nutritional immunity and determining virulence. Therefore, we employed a hybridization-based technique to compare the prevalence of five heme acquisition genes (hxuA, hxuB, hxuC, hemR, and hup) between 514 middle ear strains from children with AOM and 235 throat strains from healthy children. We also investigated their prevalences in 148 Haemophilus haemolyticus strains, a closely related species that colonizes the human pharynx and is considered to be nonpathogenic. Four out of five genes (hxuA, hxuB, hxuC, and hemR) were significantly more prevalent in the middle ear strains (96%, 100%, 100%, and 97%, respectively) than in throat strains (80%, 92%, 93%, and 85%, respectively) of NTHI, suggesting that strains possessing these genes have a virulence advantage over those lacking them. All five genes were dramatically more prevalent in NTHI strains than in H. haemolyticus, with 91% versus 9% hxuA, 98% versus 11% hxuB, 98% versus 11% hxuC, 93% versus 20% hemR, and 97% versus 34% hup, supporting their potential role in virulence and highlighting their possibility to serve as biomarkers to distinguish H. influenzae from H. haemolyticus. In summary, this study demonstrates that heme acquisition genes are more prevalent in disease-causing NTHI strains isolated from the middle ear than in colonizing NTHI strains and H. haemolyticus isolated from the pharynx.
李鹏; 何永聚; 冯书章
猪链球菌2 W(Streptococcus suis serotype 2,S.suis 2)是一种重要的人兽共患病原菌,其毒力因子在S.suis 2致病中的作用机制仍不明确,越来越多的学者开始寻找其他相关的毒力基因.本文对近几年来S.suis 2S.suis新毒力基因的研究进展作一综述.%Streptococcus suis serotype 2 (S. suis 2) is an important pathogen of zoonoses. However, the role of virulence factor in pathogenesis of S. suis 2 is still uncertain. More and more attentions are paid in investigating other virulence-related genes in recent years. This paper reviews the progress in research on novel virulence-related gene of S. suis 2.
Ekaza, Euloge; Teyssier, Jacques; Ouahrani-Bettache, Safia; Liautard, Jean-Pierre; Köhler, Stephan
Pathogens often encounter stressful conditions inside their hosts. In the attempt to characterize the stress response in Brucella suis, a gene highly homologous to Escherichia coli clpB was isolated from Brucella suis, and the deduced amino acid sequence showed features typical of the ClpB ATPase family of stress response proteins. Under high-temperature stress conditions, ClpB of B. suis was induced, and an isogenic B. suis clpB mutant showed increased sensitivity to high temperature, but also to ethanol stress and acid pH. The effects were reversible by complementation. Simultaneous inactivation of clpA and clpB resulted in a mutant that was sensitive to oxidative stress. In B. suis expressing gfp, ClpA but not ClpB participated in degradation of the green fluorescent protein at 42°C. We concluded that ClpB was responsible for tolerance to several stresses and that the lethality caused by harsh environmental conditions may have similar molecular origins. PMID:11274130
Groves, Mitchell D; Jordan, David; Chapman, Toni A; Jassim, Rafat Al
Streptococcus suis serotype 2 is a ubiquitous pathogen of swine and is known to cause severe disease in humans. Multilocus sequence typing (MLST) is ideal for characterising this organism because it permits isolates to be compared on a national and international scale. A novel approach to MLST using matrix-assisted laser desorption ionisation-time of flight mass spectrometry (MS-MLST) provides a more rapid alternative to dideoxy sequencing. This study used MS-MLST to define the multilocus sequence types (STs) present among a collection of Australian S. suis type 2, and thus, delivered a basis for comparison of Australian isolates with international strains already well characterised for virulence attributes. A collection of 45 isolates recovered from infected humans (n=3) and diseased pigs (n=42) was genotyped using MS-MLST and conventional MLST. Both methods were 100% concordant in their classification of sequence types (STs), although MS-MLST permitted much quicker analysis of sequence data. The collection contained ST25 (n=31), ST1 (n=10), ST28 (n=3) and ST369 (n=1). These results are consistent with the population structure of S. suis type 2 observed in diseased pigs and humans in Canada and the United Kingdom. MS-MLST may have utility for studying the population structure and epidemiology of S. suis in countries where the diversity of S. suis is greater and human disease is more common.
Haemophilus parasuis, the bacterium responsible for Glasser's disease, is a pathogen of significant concern in modern high-health swine production systems but there is little information regarding the identity or function of its virulence factors. Several important human mucosal pathogens, including...
Dorey, L; Hobson, S; Lees, P
Four indices of antimicrobial potency were determined for florfenicol and the pig pneumonia pathogens, Actinobacillus pleuropneumoniae and Pasteurella multocida. Minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), mutant prevention concentration (MPC) and time-kill curves were determined in two matrices, broth and pig serum. Five overlapping sets of two-fold dilutions were used to increase accuracy of the measurements. MIC and MBC serum:broth ratios for A. pleuropneumoniae were 0.96:1 and 1.07:1, respectively, and corresponding values for P. multocida were 0.72:1 and 0.50:1. The percentage binding of florfenicol to serum protein was 65.4%, and fraction unbound (fu) serum MICs were significantly lower, by 2.71-fold and 3.82-fold, respectively, than predicted for free serum concentrations for A. pleuropneumoniae and P. multocida. Similar culture medium differences were obtained for MBC and MPC. MICs in serum and broth were increased significantly and progressively for high, medium and low initial inoculum counts. Serum MPC:MIC ratios for A. pleuropneumoniae and P. multocida were 12.5:1 and 13.6:1, respectively; ratios for broth were similar. The killing action of florfenicol had the characteristics of concentration dependency for both species in both growth media. These data indicate the value of using a biological medium, when determining microbiological potency indices, to predict dosage for clinical use. Copyright © 2016 Elsevier Ltd. All rights reserved.
Yang, Feng; Ma, Qiuyue; Lei, Liancheng; Huang, Jing; Ji, Qun; Zhai, Ruidong; Wang, Lei; Wang, Yu; Li, Linxi; Sun, Changjiang; Feng, Xin; Han, Wenyu
Porcine contagious pleuropneumonia, caused by Actinobacillus pleuropneumoniae, has a major impact on economics, ecology, and animal welfare in the pig-rearing industry. Propionibacterium acnes, a facultative anaerobic Gram-positive corynebacterium, exists widely in normal healthy adult animals. We have shown previously that P. acnes can prevent A. pleuropneumoniae infections in mice and pigs. To elucidate the mechanism of this effect and to identify novel A. pleuropneumoniae vaccines, the role of anti-P. acnes antibodies in preventing infection was analyzed by indirect immunofluorescence and opsonophagocytosis assays in vitro. The role of the specific humoral immune response induced by P. acnes was confirmed in a B cell depletion mouse model. The survival rates of mice challenged with A. pleuropneumoniae exhibited a highly significant positive rank correlation with the levels of anti-P. acnes antibodies. The specific antibodies induced by P. acnes had the ability to combine with A. pleuropneumoniae and increase opsonization of A. pleuropneumoniae for phagocytosis. Furthermore, analysis in the murine B cell depletion model confirmed that the humoral immune response induced by P. acnes played an important role in resistance to A. pleuropneumoniae infection. In this study, we further elucidated the reasons that P. acnes can prevent A. pleuropneumoniae infection, which provides useful evidence for the development of heterologous vaccines for the control of porcine contagious pleuropneumonia.
Full Text Available Actinobacillus pleuropneumoniae is the etiologic agent of porcine contagious pleuropneumonia, a cause of considerable world wide economic losses in the swine industry. We sequenced the complete genome of A. pleuropneumoniae, JL03, an isolate of serotype 3 prevalent in China. Its genome is a single chromosome of 2,242,062 base pairs containing 2,097 predicted protein-coding sequences, six ribosomal rRNA operons, and 63 tRNA genes. Preliminary analysis of the genomic sequence and the functions of the encoded proteins not only confirmed the present physiological and pathological knowledge but also offered new insights into the metabolic and virulence characteristics of this important pathogen. We identified a full spectrum of genes related to its characteristic chemoheterotrophic catabolism of fermentation and respiration with an incomplete TCA system for anabolism. In addition to confirming the lack of ApxI toxin, identification of a nonsense mutation in apxIVA and a 5'-proximal truncation of the flp operon deleting both its promoter and the flp1flp2tadV genes have provided convincing scenarios for the low virulence property of JL03. Comparative genomic analysis using the available sequences of other serotypes, probable strain (serotype-specific genomic islands related to capsular polysaccharides and lipopolysaccharide O-antigen biosyntheses were identified in JL03, which provides a foundation for future research into the mechanisms of serotypic diversity of A. pleuropneumoniae.
Pereira, Monalessa Fábia; Rossi, Ciro César; de Queiroz, Marisa Vieira; Martins, Gustavo Ferreira; Isaac, Clement; Bossé, Janine T; Li, Yanwen; Wren, Brendan W; Terra, Vanessa Sofia; Cuccui, Jon; Langford, Paul R; Bazzolli, Denise Mara Soares
Actinobacillus pleuropneumoniae is responsible for swine pleuropneumonia, a respiratory disease that causes significant global economic loss. Its virulence depends on many factors, such as capsular polysaccharides, RTX toxins and iron-acquisition systems. Analysis of virulence may require easy-to-use models that approximate mammalian infection and avoid ethical issues. Here, we investigate the potential use of the wax moth Galleria mellonella as an informative model for A. pleuropneumoniae infection. Genotypically distinct A. pleuropneumoniae clinical isolates were able to kill larvae at 37 °C but had different LD50 values, ranging from 10(4) to 10(7) c.f.u. per larva. The most virulent isolate (1022) was able to persist and replicate within the insect, while the least virulent (780) was rapidly cleared. We observed a decrease in haemocyte concentration, aggregation and DNA damage post-infection with isolate 1022. Melanization points around bacterial cells were observed in the fat body and pericardial tissues of infected G. mellonella, indicating vigorous cell and humoral immune responses close to the larval dorsal vessel. As found in pigs, an A. pleuropneumoniae hfq mutant was significantly attenuated for infection in the G. mellonella model. Additionally, the model could be used to assess the effectiveness of several antimicrobial agents against A. pleuropneumoniae in vivo. G. mellonella is a suitable inexpensive alternative infection model that can be used to study the virulence of A. pleuropneumoniae, as well as assess the effectiveness of antimicrobial agents against this pathogen. © 2015 The Authors.
Dorey, L; Hobson, S; Lees, P
Pharmacodynamic properties of marbofloxacin were established for six isolates each of the pig respiratory tract pathogens, Actinobacillus pleuropneumoniae and Pasteurella multocida. Three in vitro indices of potency were determined; Minimum Inhibitory Concentration (MIC), Minimum Bactericidal Concentration (MBC) and Mutant Prevention Concentration (MPC). For MIC determination Clinical Laboratory Standards Institute guidelines were modified in three respects: (1) comparison was made between two growth media, an artificial broth and pig serum; (2) a high inoculum count was used to simulate heavy clinical bacteriological loads; and (3) five overlapping sets of two-fold dilutions were used to improve accuracy of determinations. Similar methods were used for MBC and MPC estimations. MIC and MPC serum:broth ratios for A. pleuropneumoniae were 0.79:1 and 0.99:1, respectively, and corresponding values for P. multocida were 1.12:1 and 1.32:1. Serum protein binding of marbofloxacin was 49%, so that fraction unbound (fu) serum MIC values were significantly lower than those predicted by correction for protein binding; fu serum:broth MIC ratios were 0.40:1 (A. pleuropneumoniae) and 0.50:1 (P. multocida). For broth, MPC:MIC ratios were 13.7:1 (A. pleuropneumoniae) and 14.2:1 (P. multocida). Corresponding ratios for serum were similar, 17.2:1 and 18.8:1, respectively. It is suggested that, for dose prediction purposes, serum data might be preferable to potency indices measured in broths. Copyright © 2016 Elsevier Ltd. All rights reserved.
Kim, Boram; Hur, Jin; Lee, Ji Yeong; Choi, Yoonyoung; Lee, John Hwa
Actinobacillus pleuropneumoniae (APP) causes porcine pleuropneumonia (PP). Serotypes and antimicrobial resistance patterns in APP isolates from pigs in Korea were examined. Sixty-five APP isolates were genetically serotyped using standard and multiplex PCR (polymerase chain reaction). Antimicrobial susceptibilities were tested using the standardized disk-agar method. PCR was used to detect β-lactam, gentamicin and tetracycline-resistance genes. The random amplified polymorphic DNA (RAPD) patterns were determined by PCR. Korean pigs predominantly carried APP serotypes 1 and 5. Among 65 isolates, one isolate was sensitive to all 12 antimicrobials tested in this study. Sixty-two isolates was resistant to tetracycline and 53 isolates carried one or five genes including tet(B), tet(A), tet(H), tet(M)/tet(O), tet(C), tet(G) and/or tet(L)-1 markers. Among 64 strains, 9% and 26.6% were resistance to 10 and three or more antimicrobials, respectively. Thirteen different antimicrobial resistance patterns were observed and RAPD analysis revealed a separation of the isolates into two clusters: cluster II (6 strains resistant to 10 antimicrobials) and cluster I (the other 59 strains). Results show that APP serotypes 1 and 5 are the most common in Korea, and multi-drug resistant strains are prevalent. RAPD analysis demonstrated that six isolates resistant to 10 antimicrobials belonged to the same cluster.
Dorey, L; Hobson, S; Lees, P
For the pig respiratory tract pathogens, Actinobacillus pleuropneumoniae and Pasteurella multocida, Minimum Inhibitory Concentration (MIC) of marbofloxacin was determined in recommended broths and pig serum at three inoculum strengths. MICs in both growth matrices increased progressively from low, through medium to high starting inoculum counts, 10(4), 10(6) and 10(8)CFU/mL, respectively. P. multocida MIC ratios for high:low inocula were 14:4:1 for broth and 28.2:1 for serum. Corresponding MIC ratios for A. pleuropneumoniae were lower, 4.1:1 (broth) and 9.2:1 (serum). MIC high:low ratios were therefore both growth matrix and bacterial species dependent. The effect of alterations to the chemical composition of broths and serum on MIC were also investigated. Neither adjusting broth or serum pH in six increments over the range 7.0 to 8.0 nor increasing calcium and magnesium concentrations of broth in seven incremental steps significantly affected MICs for either organism. In time-kill studies, the killing action of marbofloxacin had the characteristics of concentration dependency against both organisms in both growth matrices. It is concluded that MIC and time-kill data for marbofloxacin, generated in serum, might be preferable to broth data, for predicting dosages of marbofloxacin for clinical use. Copyright © 2016 Elsevier Ltd. All rights reserved.
Chen, Xiabing; Xu, Zhuofei; Li, Lu; Chen, Huanchun; Zhou, Rui
Actinobacillus pleuropneumoniae is an important swine respiratory pathogen causing great economic losses worldwide. Identification of conserved surface antigenic proteins is helpful for developing effective vaccines. In this study, a genome-wide strategy combined with bioinformatic and experimental approaches, was applied to discover and characterize surface-associated immunogenic proteins of A. pleuropneumoniae. Thirty nine genes encoding outer membrane proteins (OMPs) and lipoproteins were identified by comparative genomics and gene expression profiling as being-highly conserved and stably transcribed in the different serotypes of A. pleuropneumoniae reference strains. Twelve of these conserved proteins were successfully expressed in Escherichia coli and their immunogenicity was estimated by homologous challenge in the mouse model, and then three of these proteins (APJL_0126, HbpA and OmpW) were further tested in the natural host (swine) by homologous and heterologous challenges. The results showed that these proteins could induce high titers of antibodies, but vaccination with each protein individually elicited low protective immunity against A. pleuropneumoniae. This study gives novel insights into immunogenicity of the conserved OMPs and lipoproteins of A. pleuropneumoniae. Although none of the surface proteins characterized in this study could individually induce effective protective immunity against A. pleuropneumoniae, they are potential candidates for subunit vaccines in combination with Apx toxins.
Reiner, Gerald; Bertsch, Natalie; Hoeltig, Doris; Selke, Martin; Willems, Hermann; Gerlach, Gerald Friedrich; Tuemmler, Burkhard; Probst, Inga; Herwig, Ralf; Drungowski, Mario; Waldmann, Karl Heinz
Actinobacillus pleuropneumoniae is among the most important pathogens worldwide in pig production. The agent can cause severe economic losses due to decreased performance, acute or chronic pleuropneumonia and an increased incidence of death. Therapeutics cannot be used in a sustainable manner, and vaccination is not always available, but discovering more about host defence and disease mechanisms might lead to new methods of prophylaxis. The aim of the present study was to detect quantitative trait loci (QTL) associated with resistance/susceptibility to A. pleuropneumoniae. Under controlled conditions, 170 F2 animals of a Hampshire/Landrace family, with known differences in founder populations regarding A. pleuropneumoniae resistance, were challenged with an A. pleuropneumoniae serotype 7 aerosol followed by a detailed clinical, radiographic, ultrasonographic, pathological and bacteriological examination. F2 pigs were genotyped with 159 microsatellite markers. Significant QTL were identified on Sus scrofa chromosomes (SSC) 2, 6, 12, 13, 16, 17 and 18. They explained 6-22% of phenotypic variance. One QTL on SSC2 reached significance on a genome-wide level for five associated phenotypic traits. A multiple regression analysis revealed a combinatory effect of markers SWR345 (SSC2) and S0143 (SSC12) on Respiratory Health Score, Clinical Score and the occurrence of death. The results indicate the genetic background of A. pleuropneumoniae resistance in swine and provide new insights into the genetic architecture of resistance/susceptibility to porcine pleuropneumonia. The results will be helpful in identifying the underlying genes and mechanisms.
Maldonado, Jaime; Blanco, Mónica; Martínez, Eva; Navas, Jesús
Three tests for typing clinical isolates of Actinobacillus pleuropneumoniae biovar 2 were compared: 1) standard coagglutination with type-specific antisera against serovars 1-12 of biovar 1 of A. pleuropneumoniae; 2) a previously described polymerase chain reaction system for detecting the apx genes encoding the ApxI, ApxII, and ApxIII toxins in A. pleuropneumoniae; and 3) a restriction fragment length polymorphism analysis of the transferrin-binding protein B gene. The panel of strains tested included 112 field isolates of biovar 2 recovered from pigs between 1979 and 2007 in Italy and Spain, and reference strains for all described serovars of both biovars. The values of Simpson index of diversity obtained for the 3 methods were 0.68, 0.20, and 0.60, respectively. Coagglutination assays identified the field isolates as belonging to serovars 2 (9 strains), 4 (13 strains), 7 (61 strains), 9 (17 strains), and 11 (1 strain). Eleven strains were not typeable, and cross-reactivity was observed between serovars 2 and 4, 4 and 7, and 9 and 11. Isolates of A. pleuropneumoniae biovar 2 displayed 2 apx patterns: ApxII(+) (94 strains) and ApxI(+)/ApxII(+) (18 strains). The restriction fragment length polymorphism analysis assigned the strains tested to 3 different patterns. This method distinguished between biovar 2 reference strains and field strains that could not be identified by other methods, thus constituting a useful complementary test for the typing of A. pleuropneumoniae biovar 2.
Kim, Mi-Young; Kim, Tae-Geum; Yang, Moon-Sik
Actinobacillus pleuropneumoniae is a major etiological agent that is responsible for swine pleuropneumonia, a highly contagious respiratory infection that causes severe economic losses in the swine production industry. ApxIIA is one of the virulence factors in A. pleuropneumoniae and has been considered as a candidate for developing a vaccine against the bacterial infection. A gene encoding an ApxIIA fragment (amino acids 439-801) was modified based on a plant-optimized codon and constructed into a plant expression vector under the control of a promoter and the 3' UTR of the rice amylase 3D gene. The plant expression vector was introduced into rice embryogenic callus (Oryza sativa L. cv. Dongjin) via particle bombardment-mediated transformation. The integration and transcription of the ApxIIA439-801 gene were confirmed by using genomic DNA PCR amplification and Northern blot analysis, respectively. The synthesis of ApxIIA439-801 antigen protein in transgenic rice callus was confirmed by western blot analysis. The concentration of antigen protein in lyophilized samples of transgenic rice callus was 250 μg/g. Immunizing mice with protein extracts from transgenic plants intranasally elicited secretory IgA. These results demonstrate the feasibility of using a transgenic plant to elicit immune responses against A. pleuropneumoniae. Copyright © 2017 Elsevier Inc. All rights reserved.
Full Text Available Cytotoxins produced by Actinobacillus pleuropneumoniae are supposed to play major roles in bacterial pathogenicity and virulence. To gain better understanding in the mechanism of the pathogenicity, cytotoxic activities of the toxins on porcine neutrophils were investigated in vitro. Changes in cell size, granularity and viability were examined with a flow cytometer. Cell size and granularity correlate with forward light scatter and right angle light scatter, respectively; whereas, cell viability corresponds with fluorescent intensity of cells stained with propidium iodide . At low concentrations (dilutions between 1/10 and 1/100 of bacterial culture supernatants, the cytotoxins induced severe swelling and degranulation of neutrophils; whereas, at higher concentrations (dilutions of 51/10 bacterial culture supernatants, the cytotoxins caused rapid cell death. There was no significant difference in cytotoxic activities of Cyooxins derived from various serotypes (serotypes 1, 2, 3, 5 and 7 of A. pleuropneumoniae . Morphologically, the cytotoxin-treated neutrophils stained with Giemsa showed profound changes. Neutrophils treated with low dosages of Cyooxins became swollen with spherical nuclei . Higher concentration of cytotoxins study indicates strongly that important mechanism in the caused vactiolation of cytoplasts, enlargement or disintegration of nuclei . This in vitro intoxication of neutrophils by cytotoxins produced by A. pleuropneumoniae comprises anpathogenicity of the bacteria.
Full Text Available Abstract Background Actinobacillus pleuropneumoniae is an economically important animal pathogen that causes contagious pleuropneumonia in pigs. Currently, the molecular evolutionary trajectories for this pathogenic bacterium remain to require a better elucidation under the help of comparative genomics data. For this reason, we employed a comparative phylogenomic approach to obtain a comprehensive understanding of roles of natural selective pressure and homologous recombination during adaptation of this pathogen to its swine host. Results In this study, 12 A. pleuropneumoniae genomes were used to carry out a phylogenomic analyses. We identified 1,587 orthologous core genes as an initial data set for the estimation of genetic recombination and positive selection. Based on the analyses of four recombination tests, 23% of the core genome of A. pleuropneumoniae showed strong signals for intragenic homologous recombination. Furthermore, the selection analyses indicated that 57 genes were undergoing significant positive selection. Extensive function properties underlying these positively selected genes demonstrated that genes coding for products relevant to bacterial surface structures and pathogenesis are prone to natural selective pressure, presumably due to their potential roles in the avoidance of the porcine immune system. Conclusions Overall, substantial genetic evidence was shown to indicate that recombination and positive selection indeed play a crucial role in the adaptive evolution of A. pleuropneumoniae. The genome-wide profile of positively selected genes and/or amino acid residues will provide valuable targets for further research into the mechanisms of immune evasion and host-pathogen interactions for this serious swine pathogen.
Wyns, H; Croubels, S; Vandekerckhove, M; Demeyere, K; De Backer, P; Goddeeris, B M; Meyer, E
Porcine pleuropneumonia is a severe respiratory disease caused by Actinobacillus (A.) pleuropneumoniae. The aim of the present study was to analyze serum samples of A. pleuropneumoniae-infected pigs for TNF-α, IL-1β and IL-6 using a cytometric bead array (CBA) 3-plex assay and additionally for IL-6 using ELISA. The CBA 3-plex assay was successfully validated for use in serum. The limits of detection varied between 0.012 and 0.333 ng/mL, and the inter- and inter-assay coefficients of variation were pleuropneumoniae. Mean peak concentrations of TNF-α and IL-6 were recorded at 12h and at 10h p.i., respectively. For IL-6, similar concentration-time profiles were observed with CBA and ELISA. It is proposed that this immuno-assay can be applied for the screening of immunomodulatory properties of drugs and vaccine adjuvants in infection, inflammation and vaccination. Copyright © 2015 Elsevier Ltd. All rights reserved.