In vitro cell compatibility and antibacterial activity of microencapsulated doxycycline designed for improved localized therapy of septic arthritis

OBJECTIVES: For the treatment of septic arthritis in large animals, the local application of antibiotics as a slow release system may be an appropriate means to reach high local bioactivity and low systemic side effects and drug residues. In this study, doxycycline microspheres were developed and tested in vitro for their drug-release properties, suitability for intra-articular application and antimicrobial activity. METHODS: The development of a slow release system was achieved by microencapsulation of the drug into poly(lactide-co-glycolide) microspheres by a novel ultrasonic atomization method. Drug elution was evaluated from microspheres dispersed in elution medium at pre-defined time points by HPLC. Joint-tissue compatibility was tested on cultured bovine synoviocytes by evaluating the expression of pro-inflammatory cytokine mRNA and the production of nitric oxide (NO). Finally, the antimicrobial activity of the released antibiotic was assessed with gram-negative and gram-positive bacteria exposed to release medium sampled at days 1, 7 and 12 after microsphere suspension. RESULTS: An adequate size of the microspheres, sufficient stabilization of doxycycline in aqueous environment and drug release (25 mg microspheres in 4 mL medium) above MIC for bacteria usually isolated in bovine and equine joints were obtained over 15 days. Although the cytokine mRNA expression reflected the excellent tissue compatibility, the results with NO yielded contradictory results. Antimicrobial tests of the release medium proved to match perfectly the activity of non-encapsulated, free doxycycline as reported in the literature. CONCLUSIONS: The newly developed doxycycline delivery system achieved the target specifications and is ready for in vivo testin

Detection of Borrelia-specific 16S rRNA sequence in total RNA extracted from Ixodes ricinus ticks

A reverse transcriptase - polymerase chain reaction based assay for Borrelia species detection in ticks was developed. The method was based on amplification of 552 nucleotide bases long sequence of 16S rRNA, targeted by Borrelia specific primers. In the present study, total RNA extracted from Ixodes ricinus ticks was used as template. The results showed higher sensitivity for Borrelia detection as compared to standard dark-field microscopy. Method specificity was confirmed by cloning and sequencing of obtained 552 base pairs long amplicons. Phylogenetic analysis of obtained sequences showed that they belong to B. lusitaniae and B. afzelii genospecies. RT-PCR based method presented in this paper could be very useful as a screening test for detecting pathogen presence, especially when in investigations is required extraction of total RNA from ticks

Investigation of Chlamydophila spp. in dairy cows with reproductive disorders

<p>Abstract</p> <p>Background</p> <p>Reports worldwide indicate high prevalence of <it>Chlamydophila </it>spp. infection in cattle. To assess the prevalence in Sweden, 525 cows in 70 dairy herds with reproductive disorders was investigated.</p> <p>Methods</p> <p>To detect antibodies two commercially available kits were used. Moreover, 107 specimens, including vaginal swabs, organ tissues and milk were analysed by Polymerase Chain Reaction (PCR).</p> <p>Results</p> <p>Two (0.4%) cows were seropositive in the Pourquier <it>Cp. abortus </it>ELISA. The seroprevalence with the Chekit ELISA was 28% with no difference between cases and controls. Five specimens were positive in real-time PCR and further analysed by nested PCR. <it>Cp. pecorum </it>was confirmed by partial <it>omp1 </it>DNA sequencing of the nested PCR product of vaginal swabs from control cows.</p> <p>Conclusion</p> <p>The results suggest that <it>Cp. abortus </it>infection is absent or rare in Swedish cows whereas <it>Cp. pecorum </it>is probably more spread. They also suggest that <it>Chlamydophila </it>spp. are not related to reproduction disorders in Swedish cattle.</p

Parts of Me : Identity-Relevance Moderates Self-Prioritization

Recent research has revealed a pervasive bias for self-relevant information during decision-making, a phenomenon termed the self-prioritization effect. Focusing almost exclusively on between-target (e.g., self vs. friend) differences in task performance, however, this work has overlooked the influence stimulus factors potentially exert during decisional processing. Accordingly, based on pertinent socialpsychological theorizing (i.e., Identity-Based Motivation Theory), here we explored the possibility that self-prioritization is sensitive to the identity-based relevance of stimuli. The results of three experiments supported this hypothesis. In a perceptual-matching task, stimulus enhancement was greatest when geometric shapes were associated with identity-related information that was important (vs. unimportant) to participants. In addition, hierarchical drift-diffusion modeling revealed this effect was underpinned by differences in the efficiency of visual processing. Specifically, evidence was extracted more rapidly from stimuli paired with consequential compared to inconsequential identityrelated components. These findings demonstrate how identity-relevance moderates self-prioritization