Full length MHC IIβ exon 2 primers for salmonids: a new resource for next generation sequencing

Major histocompatibility complex (MHC) genes are often implicated in disease resistance, sexual selection and local adaptation in salmonids, a highly studied and socio-economically important taxa. However, genotyping highly polymorphic genes is difficult, expensive, and prone to PCR and cloning artifacts that can result in false alleles. With the advent of next generation sequencing, it is possible to effectively “clone” PCR products in a massively parallel fashion with the use of individually-tagged fusion primers. Primers that amplify a gene of interest across a variety of taxa, a single set of 50–150 primers can facilitate cost efficient genotyping and become a common lab resource. Here we developed MHC IIβ exon 2 primers for full-length amplification, including an additional PBR region, and demonstrate effectiveness with representatives from five genera of salmonids. These primers may facilitate parallel next generation sequencing for efficient, cost effective, and accurate genotyping of this complex locus.     

Efficacy and safety of deferasirox at low and high iron burdens: results from the EPIC magnetic resonance imaging substudy

The effect of deferasirox dosing tailored for iron burden and iron loading based on liver iron concentration (LIC) was assessed over 1 year in less versus more heavily iron-overloaded patients in a substudy of the Evaluation of Patients’ Iron Chelation with Exjade®. Deferasirox starting dose was 10–30 mg/kg/day, depending on blood transfusion frequency, with recommended dose adjustments every 3 months. Therapeutic goals were LIC maintenance or reduction in patients with baseline LIC <7 or ≥7 mg Fe/g dry weight (dw), respectively. Changes in LIC (R2-magnetic resonance imaging) and serum ferritin after 1 year were assessed. Adverse events (AEs) and laboratory parameters were monitored throughout. Of 374 patients, 71 and 303 had baseline LIC <7 and ≥7 mg Fe/g dw, respectively; mean deferasirox doses were 20.7 and 27.1 mg/kg/day (overall average time to dose increase, 24 weeks). At 1 year, mean LIC and median serum ferritin levels were maintained in the low-iron cohort (?0.02?±?2.4 mg Fe/g dw, ?57 ng/mL; P?=?not significant) and significantly decreased in the high-iron cohort (?6.1?±?9.1 mg Fe/g dw, ?830 ng/mL; P?<?0.0001). Drug-related gastrointestinal AEs, mostly mild to moderate, were more frequently reported in the <7 versus ≥7 mg Fe/g dw cohort (39.4 versus 20.8 %; P?=?0.001) and were not confounded by diagnosis, dosing, ethnicity, or hepatitis B and/or C history. Reported serum creatinine increases did not increase in low- versus high-iron cohort patients. Deferasirox doses of 20 mg/kg/day maintained LIC <7 mg Fe/g dw and doses of 30 mg/kg/day were required for net iron reduction in the high-iron cohort, with clinically manageable safety profiles. The higher incidence of gastrointestinal AEs at lower iron burdens requires further investigation.     

Efficacy and safety of lowering immunosuppression to treat CMV infection in renal transplant recipients on valaciclovir prophylaxis: a pilot study.

BACKGROUND: Routine cytomegalovirus (CMV)-pp65 antigenaemia monitoring shows that some patients will develop pp65 antigenaemia during valaciclovir prophylaxis or after cessation of treatment. The aim of this pilot study was to evaluate the safety and efficacy of lowering immunosuppression in kidney transplant recipients who exhibit mildly symptomatic CMV infections while on valaciclovir prophylaxis. METHODS: We selected 12 patients who experienced mildly symptomatic CMV infections defined as a positive CMV-pp65 antigenaemia test associated with either neutropenia, asthenia or arthralgia, but no fever. All of them received prophylaxis with valaciclovir for at least 3 months. Testing for CMV-pp65 antigenaemia was performed weekly for 6 months. RESULTS: The mildly symptomatic infections occurred at a median interval of 69 days after transplantation-during prophylaxis in eight cases and after valaciclovir discontinuation in the other four cases. All of them were effectively managed by lowering immunosuppressive therapy, leading to the disappearance of symptoms and CMV antigenaemia reduction. No immunological complication or recurrence of CMV infection or disease was noted. I.v. ganciclovir never became necessary. CONCLUSION: The mildly symptomatic CMV infections occurring in valaciclovir-treated patients may be managed efficiently and without immunologic complication by lowering immunosuppressive therapy.     

Understanding breastfeeding behavior: rates and shifts in patterns in Québec.

The study objective was to measure breastfeeding rates and patterns in the Montérégie region of Québec. A survey of 632 mothers of 6-month-old infants was performed, of which 80% initiated breastfeeding, and 68% exclusively breastfed at birth. Breastfeeding rates progressively decreased with time: 63%, 56%, 51%, 44%, 39%, and 32% of mothers breastfed at 1, 2, 3, 4, 5, and 6 months, respectively. Among mothers breastfeeding at a given period, 62%, 57%, 48%, 35%, and 10% of women exclusively breastfed since birth for 1, 2, 3, 4, and 5 months, respectively. Exclusive breastfeeding for 6 months among the 200 women still breastfeeding was practically nonexistent. Introduction of nonhuman milk or solids was primarily responsible for the shift in patterns from exclusive to complementary feeding without passing through predominant breastfeeding. These findings confirm the need to prioritize effective hospital-based and community-based interventions to increase breastfeeding duration and exclusivity in the region.     

Effect of an Enterococcus faecium probiotic on specific IgA following live Salmonella Enteritidis vaccination of layer chickens

Probiotics and immunization are being widely adopted by the poultry industry with the goal of controlling Salmonella enterica. However, the interaction between these two management protocols has been sparsely studied. The present study aimed to understand the role of an Enterococcus faecium probiotic in the production of salmonella-specific IgA in layers immunized with a live vaccine. Four groups were used: “Control” (no vaccine or probiotic); “Probiotic” (which received an E. faecium product); “Vaccine” (immunized with two doses of a live attenuated S. Enteritidis vaccine); and “Vaccine?+?probiotic”. Faecal salmonella-specific IgA was analysed 7 and 20 days post-vaccination (dpv) boost. At 7 dpv, the “Vaccine” and “Vaccine?+?probiotic” groups had similar IgA levels. However, at 20 dpv, IgA levels were two times higher in the “Vaccine?+?probiotic” group compared to the “Vaccine” group. To understand the role of the intestinal microbiota in this finding, bacterial diversity in faeces was analysed by 16S rRNA gene sequencing. The improvement in IgA production in probiotic-treated birds was accompanied by marked changes in the faecal microbiome. Some of the main differences between the “Vaccine” and “Vaccine?+?probiotic” groups included reduction of Escherichia-Shigella and increases in Blautia, Anaerotruncus and Lactobacillus in the latter group. Although no direct causal link can be established from this study design, it is possible that the E. faecium probiotic induces improved antibody production following vaccination via modulation of the intestinal microbiota.     

Diabetes was the only comorbid condition associated with mortality of invasive pneumococcal infection in ICU patients: a multicenter observational study from the Outcomerea research group

Purposes

Streptococcus pneumoniae is a leading pathogen of severe community, hospital or nursing facility infections. We sought to describe characteristics of invasive pneumococcal infection (IPI) and pneumonia (due to the high mortality of intensive care-associated pneumonia) and to report outcomes according to various types of comorbidity.

Methods

Multicenter observational cohort study on the prospective Outcomerea database, including adult patients, with a hospital stay?<?48 h before ICU admission and a documented IPI within the first 72 h of ICU admission. Comorbid conditions were defined according to the Knaus and Charlson classification.

Results

Of the 20,235 patients, 5310 (26.4%) had an invasive infection, including 560/5,310 (10.6%) who had an IPI. The ICU 28-day mortality was 109/560 (19.8%). Four factors were independently associated with mortality: SOFA day 1–2: [hazard ratio (HR) 1.21; 95% confidence interval (95% CI) 1.15–1.27, p?<?0.001]; maximum lactate level day 1–2: (HR 1.07, 95% CI 1.02–1.12, p?=?0.006); diabetes mellitus: (HR 1.91, 95% CI 1.23–3.03, p?=?0.006) and appropriate antibiotics (HR 0.28, 95% CI 0.15–0.50, p?<?0.001). Comparable results were obtained when other comorbid conditions were forced into the model. Diabetes impact was more pronounced in case of micro- or macro-angiopathy (HR 4.17, 95%CI 1.68–10.54, p?=?0.003), in patients?≥?65 years old (HR 2.59, 95% CI 1.56–4.28, <?0.001) and in those with body mass index (BMI)?<?25 kg/m² (HR 2.11, 95% CI 1.10–4.06, p?=?0.025).

Conclusions

Diabetes mellitus was the only comorbid condition which independently influenced mortality in patients with IPI. Its impact was more pronounced in patients with complications, aged?≥?65 years and with BMI?<?25 kg/m².