Atlantic Salmon Pre-smolt Survivors of Renibacterium salmoninarum Infection Show Inhibited Cell-Mediated Adaptive Immune Response and a Higher Risk of Death During the Late Stage of Infection at Lower Water Temperatures.

Bacterial kidney disease (BKD) is widespread in many areas of the world and can cause substantial economic losses for the salmon aquaculture industry. The objective of this study was to investigate the pathophysiological response and gene expression profiles related to the immune response at different water temperatures and to identify the best immunopathological biomarkers to define a phenotype of resistance to BKD. The abundance of msa transcripts of R. salmoninarum in the head kidney was significantly higher in infected fish at 11°C. R. salmoninarum induced significantly more severe kidney lesions, anemia and impaired renal function at 11°C. In addition, the expression pattern of the genes related to humoral and cell-mediated immune responses in infected fish at 11 and 15°C was very similar, although R. salmoninarum induced a significantly greater downregulation of the adaptive immune response genes at the lower water temperature. These results could be due to a suppressed host response directly related to the lowest water temperature and/or associated with a delayed host response related to the lowest water temperature. Although no significant differences in survival rate were observed, fish infected at the lowest temperature showed a higher probability of death and delayed the mortality curve during the late stage of infection (35 days after infection). Thirty-three immunopathological biomarkers were identified for potential use in the search for a resistance phenotype for BKD, and eight were genes related specifically to the adaptive cell-mediated immune response.

Single-Dose Bioavailability for Prophylactic Coverage in Patients Undergoing Dental Implant Surgery.

PURPOSE: The use of antibiotic prophylaxis in dental implant surgery is a routine dental practice to prevent implant failure. Current systematic reviews have yet to confirm the effectiveness of antibiotic treatment at reducing postoperative infection rates in implant procedures. The aim of this study was to quantify amoxicillin plasma levels at the peripheral venous blood and at the surgical implant site in patients undergoing dental treatment. MATERIALS AND METHODS: A prospective study was conducted. Patients undergoing dental implant surgery were selected, and preoperative doses of 1 g of amoxicillin, in the form of an oral tablet, were administered 1 hour prior to implant surgery. The blood samples (1.5 mL) were collected from both the venous and implant sites. Data on the antibiotics were measured using high-pressure liquid chromatography. The quantification method was validated for linearity, selectivity, and detection limits. Statistical analysis of plasma antibiotic was performed, comparing both samples and the age, height, weight, and body mass index (BMI) (Wilcoxon test, P < .05; STATA v.10.0). RESULTS: Thirty-two patients (mean age: 56.28 ± 12.2 years; range: 31 to 79 years; 20 men) were selected. Both blood samples were taken at a mean 1.16 ± 0.37 hours after antibiotic intake. The mean amoxicillin concentration at the implant site reached 5 ± 2.63 µg/mL (range: 2.04 to 11.18 µg/mL), while the venous blood level was 4.21 ± 2.12 µg/mL (range: 1.6 to 9.98 µg/mL) (P = .33). No correlations were observed between age, height, weight, and BMI with antibiotic plasma levels. CONCLUSION: These findings demonstrate that plasma concentrations of a prophylactic dose of amoxicillin are higher than the minimum inhibitory concentration needed to prevent the common dental bacteria involved in peri-implantitis and periodontal diseases.