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In Italy, the use of autogenous inactivated vaccines prepared with the bacterial strains isolated from affected animals is authorized by the Ministry of Health in farms where bacterial diseases occur frequently. The autogenous vaccine performed using Pasteurella multocida is frequently used in rabbit farms, but the feedback of its application is not available. Therefore, the aim of this study is to give information about the impact on the clinical signs of a bivalent autogenous vaccine in rabbits of a genetic centre. The vaccine was prepared using two P. multocida strains belonging to serogroups A and F, equipped with virulence genes and responsible for cyclical outbreak of pasteurellosis in the farm. The vaccine was administered with a first injection, followed by another one after 15 days, then another one four months after the first injection, and then continuing with a further injection every six months to all rabbits. Clinical conditions and mortality rates were monitored for two years after the first vaccination. The improvement in clinical condition and the decrease of the mortality rate were significant especially in the first year post-vaccine. In addition, the number of animals removed due to the disease decreased greatly. Based on the finding of P. multocida strains belonging to serogroup D and serogroup A equipped with different virulence-gene patterns from those previously found, we suggest that the vaccine was unable to prevent the introduction and spreading of new strains among the rabbits.

Many Mycoplasma species are involved in caprine and ovine pneumonia all over the world causing serious economic losses. These species have been reported to cause pneumonia, mastitis, arthritis, conjunctivitis and genital infection. The objective of the present study was to detect Mycoplasma species in the respiratory system of sheep and goats. So, a total of 400 samples (250 from sheep and 150 from goat) were examined bacteriologically, biochemically, by PCR, sequencing, in addition to the antibiotic susceptibility profiles screening. Only 13 isolates could be identified as Mycoplasma species. One of these sequences was submitted to the Genbank taking the accession number MK910041; Mycoplasma species 'ovine/caprine serogroup 11'. Only 7 isolates were weak biofilm producers and the other 6 isolates were non biofilm producers; 8 isolates were positive for the catalase test and 5 were negative. H2S production was recorded in 10 isolates; haemolysis was detected in only 6 isolates. In addition, the minimum inhibitory concentrations (MICs) for seven antimicrobial agents, including danofloxacin, tulathromycin, tylosin, streptomycin, lincomycin, florfenicol and oxytetracycline, were determined. All the isolates (100%) were sensitive to tulathromycin and tylosin, streptomycin and oxytetracycline; 38.5% were sensitive to danofloxacin, 69.2% were sensitive to florfenicol, while 69.2% of isolates were resistant to lincomycin. As all the isolates were recovered from apparently healthy and clinically diseased animals and identified as untyped Mycoplasma species, more investigations will be done to identify these isolates and discover their roles in infection.

In Italy, the use of autogenous inactivated vaccines prepared with the bacterial strains isolated from affected animals is authorized by the Ministry of Health in farms where bacterial diseases occur frequently. The autogenous vaccine performed using Pasteurella multocida is frequently used in rabbit farms, but the feedback of its application is not available. Therefore, the aim of this study is to give information about the impact on the clinical signs of a bivalent autogenous vaccine in rabbits of a genetic centre. The vaccine was prepared using two P. multocida strains belonging to serogroups A and F, equipped with virulence genes and responsible for cyclical outbreak of pasteurellosis in the farm. The vaccine was administered with a first injection, followed by another one after 15 days, then another one four months after the first injection, and then continuing with a further injection every six months to all rabbits. Clinical conditions and mortality rates were monitored for two years after the first vaccination. The improvement in clinical condition and the decrease of the mortality rate were significant especially in the first year post-vaccine. In addition, the number of animals removed due to the disease decreased greatly. Based on the finding of P. multocida strains belonging to serogroup D and serogroup A equipped with different virulence-gene patterns from those previously found, we suggest that the vaccine was unable to prevent the introduction and spreading of new strains among the rabbits., Competing Interests: No potential conflict of interest was reported by the author(s)., (© 2024 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.)

Abstract Background Staphylococcus epidermidis has emerged as an often encountered pathogen responsible for hospital-acquired infections. The aim of present study is to investigate the microbiological characteristic of S. epidermidis isolates isolated from sterile specimens and skin in a Chinese tertiary hospital. Methods A total of 223 non-duplicate S. epidermidis were collected from various sterile specimens of inpatients among 10 years in Wenzhou, China. 106 S. epidermidis obtained from the skin (urethral orifices) of healthy volunteers. All isolates were tested for antimicrobial susceptibility. PCR was used to detect the virulence- and resistance-associated genes and 7 housekeeping genes to determine the sequence types (STs) of selected isolates. Results The resistance rates to antimicrobials tested except linezolid and vancomycin and the prevalence of methicillin-resistant S. epidermidis (MRSE) of S. epidermidis clinical isolates were significantly higher than those among colonized isolates (P 90%), which was similar to the characteristics of ST59 clone with one locus difference from ST466. ST466 clone competence with Staphylococcus aureus was relatively stronger, relative to ST2, ST20, ST130 and ST59 clones. Conclusion Taken together, a high-level of genetic diversity was found between clinical and colonized S. epidermidis isolates. A novel ST466 clone with distinct and similar characteristics relative to other prevalent clones, emerging as a prevalent clone in China, should be of major concern.

Background Helicobacter pylori, a gram negative bacterium, colonizes the stomach in a majority of the world population. The two major virulence factors of H. pylori Vac A and Cag A, thought to be associated with chronic inflammation and disease, have been extensively studied, but the regulation of the expression of these virulence genes in H. pylori remains poorly understood. Methods qRT-PCR was performed to quantify gene expression in unadhered and AGS-adhered H. pylori. Δ fur mutant was constructed by splicing by overlap extension PCR and allelic exchange. Results Adherence of H. pylori to the gastric epithelial cell line AGS strongly induces the expression of both cagA and vacA. Induction of cagA and vacA in the AGS cell-adhered H. pylori Δ fur mutant strain was consistently lower than in the adhered parent strain. However, expression of the genes was similar between the wild-type and Δ fur mutant strains in the unadhered state, suggesting that Fur has a role in the upregulation of cagA and vacA expression, especially in AGS-adhered H. pylori. Consistent with these results, microscopic observations revealed that infection of AGS cells with H. pylori Δ fur mutant strain produced much less damage as compared to that produced by the wild-type H. pylori strain. Conclusions These results suggested that cagA and vacA gene expression is upregulated in H. pylori, especially by host cell contact, and Fur has a role in the upregulation. [ABSTRACT FROM AUTHOR]

Background: The detection of the putative disease-specific Helicobacter pylori marker duodenal ulcer promoting gene A ( dupA) is currently based on PCR detection of jhp0917 and jhp0918 that form the gene. However, mutations that lead to premature stop codons that split off the dupA leading to truncated products cannot be evaluated by PCR. Methods: We directly sequence the complete dupA of 75 dupA-positive strains of H. pylori isolated from patients with gastritis (n = 26), duodenal ulcer (n = 29), and gastric carcinoma (n = 20), to search for frame-shifting mutations that lead to stop codon. Results: Thirty-four strains had single nucleotide mutations in dupA that lead to premature stop codon creating smaller products than the predicted 1839 bp product and, for this reason, were considered as dupA-negative. Intact dupA was more frequently observed in strains isolated from duodenal ulcer patients (65.5%) than in patients with gastritis only (46.2%) or with gastric carcinoma (50%). In logistic analysis, the presence of the intact dupA independently associated with duodenal ulcer (OR = 5.06; 95% CI = 1.22-20.96, p = .02). Conclusion: We propose the primer walking methodology as a simple technique to sequence the gene. When we considered as dupA-positive only those strains that carry dupA gene without premature stop codons, the gene was associated with duodenal ulcer and, therefore, can be used as a marker for this disease in our population. [ABSTRACT FROM AUTHOR]

Abstract Background. In recent years, numerous PCR amplification typing methods have been developed for the identification of H. pylori specific virulence genes. To reduce the number of PCR amplifications needed we have previously developed virulence gene based multiplex PCR and RT-PCR assays. Aim. The aim of the present study was to characterise Helicobacter pylori strains by means of virulence-gene based multiplex PCR and reverse-transcription PCR. Subjects. Helicobacter pylori clinical reference strains HP-HJM 1–25 originally obtained from routine cultures of clinical gastric biopsy specimens from dyspeptic patients were used in the present study. Methods. Helicobacter pylori multiplex PCR and RT-PCR assays were carried out using primer pairs targeting the cagA , vacA , ureA , ureI , hspA (hsp60 ), and sodB genes and their cDNA. Results. Unexpected multiplex PCR and RT-PCR patterns were observed by ethidium bromide staining of agarose gels and Southern blot hybridisation analysis. DNA sequence analysis revealed a complex pattern of point mutations, deletions and insertions in the sodB , cagA and vacA genes, respectively. Mutations occurring in the PCR and hybridisation primer binding sites might explain some of the discrepancies previously observed in the expression of these genes. Furthermore, the present data show that coexpression of cagA and vacA transcripts of different sizes may take place in the same strain. Conclusions. The multiplex PCR and RT-PCR assay described allows rapid characterisation of H. pylori virulence genes at the DNA and RNA (cDNA) levels. However, extensive DNA sequence analysis seems necessary if one wants to reveal details of mutations occurring in the cagA and vacA genes. [ABSTRACT FROM AUTHOR]