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Identical classifications of RTX-toxins of Actinobacillus pleuropneumoniae and their genes were proposed after studying three diverse pore-forming RTX-toxins of this organism. The RTX-toxin derived from the reference strains for serotypes 1, 5a, 5b, 9, 10 and 11 were termed Apxl. This protein was found to be highly haemolytic and reveals increased cytotoxic activity toward pig alveolar macrophages and neutrophils, and has a molecular mass between 105 and 110kDa.

Objectives: This study provides a direct comparison between two registration systems used in quantifying mandibular opening movements: two-dimensional videography and electronic axiography, which is used as a reference.Method: A total of 32 volunteers (age: 27.2 ± 6.8 - gender: 17 F - 15 M) participated in the study and repeated a characteristic movement, the frontal Posselt, used in the clinical evaluation of the temporomandibular joint.Results: Frontal Posselt diagrams were reconstructed with the data gathered from both systems, which yielded acceptably similar data. Three commonly assessed parameters were obtained from each diagram and compared. These parameters were: maximum opening, right laterotrusion and left laterotrusion. Both descriptive statistics and the ANOVA test suggested that there was no significant difference between the estimated maximum opening parameter and the reference system (p = 0.217, 95% confidence). Laterotrusion values, on the other hand, appear to be overestimated by videography system and to show greater variability.Discussion: Two-dimensional videography appears to be a suitable tool with resolution that is adequate for tracing mandibular movements - and opening values, in particular - for screening purposes, long-term observation, and as a quick check for dysfunction as far as frontal plane trajectories are concerned.Conclusion: Reliability and acceptable quality of 2D videography data, acquired in this work, show that it has clear advantages for its wide application in the dental office due to simplicity and low cost for maximum opening measurement given the usefulness of this parameter in the detection of temporomandibular disorders. [ABSTRACT FROM AUTHOR]

In 1998, a survey was conducted by postal questionnaire to gather basic knowledge about the management, health and productivity of captive deer in Switzerland. In addition, lymph nodes were collected from slaughtered deer from 124 of the 262 holdings surveyed, and tested for and . The total farmed deer population was 8389 animals kept on 485 holdings; 87 per cent were fallow deer, 8 per cent red deer, 4 per cent sika deer, and there were small numbers of other species. The median herd sizes were 12 for fallow deer and eight for red deer. Few owners had handling facilities or crushes. In none of the lymph nodes examined were lesions typical of bovine tuberculosis observed, and neither nor was cultivated from any of the samples. [ABSTRACT FROM PUBLISHER]

A specific PCR assay based on unique sequences of the rrs genes (16S rRNA) of Mycoplasma conjunctivae was developed for direct detection and identification of this pathogen from clinical material. DNA from eye swabs was amplified after a simple lysis step by either a single PCR with the M. conjunctivae specific primer pair McoR1 and McoF1, or by a nested PCR with the Mycoplasma genus specific primer pair MOLIGEN1-L and 16UNI-R in the first step and McoR1 and McoF1 in the second step. The specificity of the primer pair McoR1 and McoF1 was verified with purified DNA from the type strain, from 17 field isolates of M. conjunctivae and from several Mollicutes which are phylogenetically related to M. conjunctivae or which can be isolated from the same host animals. This method identified mycoplasma isolates from goat, sheep, ibex and chamois originating from different countries as M. conjunctivae. No cross amplifications with other mycoplasmas which are related to M. conjunctivae were observed. Eye swab samples containing known numbers of M. conjunctivae cells were analysed after direct lysis of the material. The detection level was estimated to be 20 cells per swab when the nested PCR procedure was used and 2 × 105 by the single PCR method. In an experimental infection model of sheep, the nested PCR method for detection of M. conjunctivae gave results which were comparable to mycoplasmal culture. These are the implications for diagnostic purposes: M. conjunctivae isolates can be identified by the one-step PCR method, whereas for detection and identification of M. conjunctivae in clinical material the two-step method should be used (higher sensitivity). [ABSTRACT FROM AUTHOR]

Potent immunogenicity of certain extracellular `chymotrypsin-like' enzymes of Micropolyspora faeni are demonstrated. One of them, Enzyme 1 seems particularly active in stimulating the formation of precipitins after intratracheal exposure in rabbits. Man or cattle exposed naturally to mouldy hay, either with or without clinical farmer's lung symptoms show a rather constant immunological reaction against Enzyme 1 and partly also against others of the same group. The detection of specific precipitins against these enzymes is not likely to improve the diagnostic value of the standard farmer's lung serology. Possible implications of these proteolytic enzymes in the pathogenesis of farmer's lung are discussed. [ABSTRACT FROM AUTHOR]

The diagnosis of Q fever endocarditis cannot be made by bacterial cultures and necessitates serological identification of specific antibodies to Coxiella burnetii which stimulates mainly the production of anti-phase II antibodies during the acute diséase, but primarily anti-phase I antibodies in endocarditis. Indirect micro-immunofluorescence allows rapid detection of specific IgA, IgG and IgM. The results of serological analyses of 191 acute cases of Q fever were compared with those of 8 cases of Coxiella burnetii endocarditis. All sera were evaluated by complement fixation and microimmunofluorescence tests. The highest titre differences between primary Q fever and Q fever endocarditis were observed with anti-phase IIgA and IgG antibodies measured by microimmunofluorescence followed by anti-phase I antibodies measured by complement fixation tests. Anti-phase IIgG and IgM titres were consistently higher than anti-phase II titres in endocarditis. The reverse is true in acute Q fever. In addition, anti-phase I Ig A appeared to be diagnostic for Coxiella burnetii endocarditis. Accordingly we recommend the testing of these specific IgA, IgG, and IgM by microimmunofluorescence in cases of culture-negative endocarditis. These tests could also prove useful for following the development of Coxiella burnetii endocarditis in patients under treatment. [ABSTRACT FROM PUBLISHER]

Five verotoxin producing Escherichia coli strains were detected in 405 patients with infectious gastroenteritis and 3 such strains were detected in 11 patients with the hemolytic uremic syndrome in Switzerland. Production of verotoxin 2 was associated with the latter three strains. Four strains reacted with the probe for the virulence plasmid of Escherichia coli O157:H7, and six reacted with a recently described probe for the eae gene of enteropathogenic Escherichia coli. None of the strains was of serotype O157:H7. The methods available at present for detecting toxins or toxin genes will reliably detect all such verotoxin producing strains. [ABSTRACT FROM AUTHOR]

Rabbits were exposed intratracheally to enzyme 1, a highly immunogenic esterase isolated from Micropolyspora faeni. A single exposure to active enzyme 1 induced no histologically or immuno-histochemically detectable changes in the lungs of experimental animals, while signs of focal interstitial and perivascular inflammatory reactions were evident following a course of three exposures to the enzyme. Interstitial pneumonia with characteristic generalized vasculitis and perivasculitis was produced following seven or nine inoculations. An enzymatically inactive preparation of enzyme 1, even by repeated administration, proved ineffective in eliciting pneumonia. Intracellular antigen within macrophages/histiocytes was demonstrated in the lungs of all experimental animals, including those which had been exposed to inhibited enzyme. Repeated exposure to the enzymatically active preparation resulted in the deposition of immunoglobulin and complement in association with vascular endothelia and in the walls of small- and medium- sized blood vessels; both immunoglobulin and complement could also he demonstrated within macrophages/histiocytes. On the basis of these findings it is concluded that (1) Farmer's lung- like interstitial pneumonia may be produced in rabbits by exposure to a purified, enzymatically active derivative of M. facni, (2) an important pathogenic principle of the disease may consist in the rapid vascular deposition of immune complexes (type III reaction), and (3) damage by direct enzyme action may prove to contribute significantly in eliciting tissue damage by (an) ancillary mechanism(s) not yet understood. [ABSTRACT FROM AUTHOR]

The gene encoding the c. 105kD secreted haemolysin protein of the porcine pathogen Actinobacillus pleuropneumoniae serotype 1 has been isolated by screening a lambda gt11 expression library in Escherichia coli with antiserum raised against the wild-type protein. A derivative recombinant DNA pJFF702 expressed the hlylA haemolysin gene from the pUC19 lac promoter but the resulting haemolysin I protein remained within the E. coli cell and was haemolytically inactive. Export of the intracellular A. pleuropneumoniae prohaemolysin out into the medium was achieved by the presence in trans of the E. coli haemolysin secretion genes hlyB and hlyD, and high levels of intracellular haemotytic activity were attained similarly by the E. coli post-translational haemolysin activator gene, hlyC. Southern hybridization of A. pleuropneumoniae parental DNA nevertheless indicated only a low degree of nucteotide sequence identity to the haemolysin structural and secretion genes hlyA and hlyB of E. coli. The data show that despite substantial nucleotide sequence divergence the A. pleuropneumoniae sero-type 1 haemolysin determinant is closely related to that which is dispersed throughout other Gram-negative human and animal pathogens. [ABSTRACT FROM AUTHOR]

Mycoplasma conjunctivae was isolated four times from the eyes of nine Alpine ibex ( Capra ibex ibex) suffering from keratoconjunctivitis. The animals examined were affected in two different outbreaks in the Swiss Alps. Parasitological and bacteriological studies, including investigations for chlamydia and mycoplasmas, were performed. The results indicate that M. conjunctivae is the primary pathogenic agent causing infectious keratoconjunctivitis in this species. [ABSTRACT FROM AUTHOR]

To determine the clinical significance and prevalence of Vero cytotoxin (VT)-producing E. coli (VTEC) in Swiss cattle, faecal swabs and milk samples of 93 cattle from two farms with calf diarrhoea, and of 54 cattle from two similar farms without clinical problems, were screened for VTEC by PCR and colony-blot hybridization. On average, 21% of all cows were positive for VTEC by PCR, without differences between farms with and without diarrhoea problems. By contrast, VTEC were detected by PCR in 60% of animals younger than 2 years from farms with diarrhoea problems, whereas only 32% of comparable control animals from farms without clinical problems had VTEC. No VTEC were detected in the milk samples. A variety of toxin types, antimicrobial-susceptibility patterns and serotypes were found by colony-blot hybridization, among the VTEC in individual herds. However, there was a significant relationship between the VT1-only toxin type and the presence of antimicrobial resistance and clinical disease in calves. No association could be found between levels of VTEC excretion and the presence of diarrhoea. This is the first study to report systematic quantitative data on numbers of VTEC in faecal samples of cattle positive for VT genes by PCR. [ABSTRACT FROM AUTHOR]

Clostridium perfringens type C, which produces α- and β-toxin, causes severe haemorrhagic and necrotic enteritis in animals and humans. A polymerase-chain-reaction (PCR) assay was developed for the specific detection of the genes encoding α-, β-, ε- and enterotoxin of C. perfringens for rapid typing of C. perfringens strains, and especially for the identification of type C strains. Both the α- and β-toxin genes were detected directly in porcine C. perfringens type C cultures and also in type B and type C collection strains to a sensitivity of 103 cells without purification of the DNA. The α-toxin gene was detected in all types of C. perfringens. The ε-toxin gene was found in type B and type D, and the enterotoxin gene in some type A strains. Nine other species of Clostridium and a variety of intestinal pathogenic bacteria showed no signal for these toxin genes in this PCR assay. The α- and β-toxin genes PCR assay were used to identify C. perfringens strains isolated from intestinal contents of 36 necropsied piglets that had suddenly died or died after premonitory signs of diarrhoea. At necropsy, 20 piglets showed necrotizing enteritis (15 acute and 5 chronic cases) and were suspected to have suffered from a C. perfringens type C infection. All of them had C. perfringens which gave a positive PCR signal for α- and β-toxin genes, and, hence, were identified as type C strains. From the 16 other piglets with lesions other than necrotizing enteritis, C. perfringens strains with the α-toxin gene, but no β-toxin gene, were isolated. The necropsy findings and the anamnesis showed a very good correlation with the PCR identification of toxin genes. It was therefore concluded that the PCR-based toxin gene examination is a good alternative to the time-consuming, less specific, and more expensive mouse neutralization test in the routine diagnostic laboratory. [ABSTRACT FROM AUTHOR]

A total of 70 puppies and their dams, distributed in 14 litters, were submitted to weekly fecal examinations for C. difficile during the first 10 weeks after birth. During the study, 94.3% of the puppies and 42.9% of the dams harboured C. difficile at least once in their feces. We calculated that 58% of the puppies carried toxigenic C. difficile at least once during the survey. In the puppies, C. difficile carriage rates ranging from 3.1% to 67.1% were observed at different moments of the observation period. In comparison, C. difficile carriage rate was 1.4% in a control group of healthy dogs more than 3 months old. Discrepancies in the toxigenic phenotype of the C. difficile strains isolated in the same litter showed that the neonate dogs were transiently infected with different strains, and that the dam is often not the source of infection with C. difficile. We could not demonstrate any pathogenicity of C. difficile for neonate dogs. [ABSTRACT FROM AUTHOR]

A sterile plastic tube, a boric acid-glycerol-sodium formate tube and a dip-slide tube were compared for transport of dog urine for bacteriological examination under practice conditions, at ambient temperature. In a first part, 50 dog urine samples were cultured on agar plates and on a dip-slide kit within 2 h after collection and after storage at 20°C in a sterile tube and in a boric acid tube for 24 h and 48 h. Culture of the samples stored in the boric acid tube and culture on the dip-slide yielded results which correlated very well with those of the culture of fresh urine. However, culture of the samples stored in the sterile tube yielded up to 65 % false positive results. In a second part, a comparison was drawn with culture results of 100 dog urine specimens collected by different practitioners and simultaneously mailed to our laboratory in a sterile tube, in a boric acid tube and in a dip-slide kit. Samples sent in the boric acid and in the dip-slide tube showed comparable culture results. Culture of the samples sent in the plastic tube yielded 53 % false positive results in comparison with those of the samples preserved in boric acid. [ABSTRACT FROM AUTHOR]

The scope of current diagnostic methods for Q fever endocarditis includes serology, direct demonstration of Coxiella burnetii in the resected heart valve tissue, and animal inoculation studies. Illustrated by a clinical case report, the different methods are presented and discussed. Serology represents the primary method, using the techniques of complement fixation, indirect immunofluorescence, and enzyme-linked immunosorbent assay (ELISA). The latter two techniques allow the detection of immunoglobulins G, M, and A to the phase I and II antigens of C. burnetii. After cardiac surgery, we visualized C. burnetii on smears and specifically stained it on histologic sections of the resected heart valve by light and electron microscopic immunohistochemistry. In addition, seroconversion in animals after inoculation with valve specimens confirmed the presence of C. burnetii in the heart valve. The antibody titers determined by ELISA correlated well with the patient's clinical course during the treatment period. Therefore it is suggested that its usefulness for monitoring the efficacy of antimicrobial agents in patients with Q fever endocarditis should be further evaluated. [ABSTRACT FROM AUTHOR]

Abstract: The present study aimed to improve the microbiological quality of the milk, from the cow’s udder to the selling point by container washing and disinfecting. The total counts (TC), Enterobacteriaceae counts (EBC) were used as quality indicators. The results showed a significant decrease of milk flora at the selling point, from 1.6×107 ±1.3×107 (control) to 4.8×105 ±0,8×107 (intervention) colony forming units per ml (cfu ml−1) for TC and 1.2×106 ±1.1×106 (control) to 0.9×104 ±1.1×104 (intervention) cfu ml−1 for EBC. The study suggests that in milk production area, besides udder infection and water quality, hygiene behaviour with respect to hand washing, container’s cleaning and disinfection are the key areas that remain of relevance to milk hygiene intervention. [Copyright &y& Elsevier]

The microbiological quality of raw cows’ milk, taken at different intervals from the udder to the selling point in Bamako was studied. Prior to taking the milk samples, each container and all the related material used were flushed with sterile water and bacteriological determination were made. A strong increase in the total count (TC) of bacteria was observed during transport from the farm to the market (107 colony forming unit per ml (CFU ml−1)). The main indicators considered were TC, Enterobacteriaceae and Staphylococcus aureus. The milk containers of the farmer and the milk vendor played a major role in the increase in the milk flora that occurred during transport from the farm to the selling points. [Copyright &y& Elsevier]