BoviPure® density-gradient centrifugation procedure enhances the quality of fresh and cryopreserved dog epididymal spermatozoa.

BoviPure® is a salt solution containing colloidal silica particles coated with silane used to select sperm (e.g., ruminants) by density-gradient centrifugation (DGC). This research assessed the suitability of the BoviPure-DGC and swim-up methods for selecting dog epididymal sperm in fresh, chilled and frozen-thawed samples on post-treatment sperm quality. Sperm samples (n = 60 epididymides) were recovered by retrograde flushing from thirty orchiectomized adult dogs. Thereafter, 20 sperm pools, containing sperm aliquots of three randomly selected animals, were used for chilling (at 5 ºC for 24 h) and freezing (in liquid nitrogen vapors). Sperm selection by BoviPure-DCG and swim-up was performed in both individual and pooled samples, including non-selected samples as controls. Overall, after BoviPure-DGC selection a higher sperm retrieval rate was obtained than the swim-up selection in both individual (P < 0.05) and pooled (P < 0.01) samples. BoviPure-DGC improved (P < 0.05) the total (TM) and progressive (PSM) sperm motilities, curvilinear (VCL) and straight-line (VSL) velocities, linearity (LIN), wobble (WOB), beat-cross frequency (BCF), and integrity of plasmatic (IPM) and acrosomal (IAM) membranes of individual samples in comparison with non-selected samples. In pooled samples, however, the BoviPure-DGC improved (P < 0.05) the PSM, VCL, WOB, and IPM of chilled and frozen-thawed samples. The swim-up method improved (P < 0.05) only some kinematic variables of the individual (VCL, WOB and BCF) and cryopreserved pooled samples (VCL and ALH) in comparison with non-selected samples. In conclusion, BoviPure-DGC was more effective for recovering and selecting both fresh and cryopreserved dog epididymal sperm than the swim-up procedure improving the kinematic variables, and membranes intactness.

High HCV subtype heterogeneity in a chronically infected general population revealed by high-resolution hepatitis C virus subtyping.

OBJECTIVES: This study aimed to characterize the chronically infected general hepatitis C virus (HCV) population in Barcelona using a highly sensitive subtyping method that can identify the 67 recognized HCV subtypes and diagnose mixed infection by various genotypes/subtypes in a single individual. The resulting information has implications for selecting optimal direct-acting antiviral (DAA) treatment for each patient and establishing public healthcare policies in our setting. METHODS: Consecutive HCV patients (treatment-naïve or interferon-based failures) attending Vall d'Hebron Hospital outpatient clinics from February 2015 to May 2016 (N=1473) were included in the study. Patient samples were characterized using HCV subtyping by next-generation ultra-deep pyrosequencing. RESULTS: The following genotypes (G) were found: G1 (1126/1473 (76.4%)), G4 (145/1473 (9.8%)), G3 (135/1473 (9.2%)), G2 (51/1473 (3.5%)), and G5 (1/1473 (0.1%)). Twenty-two subtypes were seen: 1b (790/1473 (53.6%)), 1a (332/1473 (22.5%)), 3a (133/1473 (9.0%)), 4d (105/1473 (7.1%)), 4a (29/1473 (2.0%)), and 2c (25/1473 (1.7%)), with 16 low-prevalence subtypes accounting for the remaining 3.0% (44/1473). There was a worrisome 1.0% (15/1473) of mixed infections. G2 (51/1473 (3.5%)) showed a high level of heterogeneity. Analyses by age groups showed a predominance of G1b over G1a (428/506 (84.6%) vs. 24/506 (4.7%)) in patients born before 1950 (N=506/1473), and similar percentages of these subtypes in those born between 1951 and 1975 (N=834/1473) (315/834, 37.8% vs. 266/834, 31.9%) and after 1976 (N=133/1473) (47/133, 35.3% vs. 42/133, 31.6%). CONCLUSIONS: Subtype distribution showed a higher level of heterogeneity than was expected, particularly for G2. Prevalence of mixed infections was around 1%. HCV subtype distribution related to patient age group suggested that patients born from 1936 to 1975 in our setting should undergo screening for the infection. Next-generation sequencing enabled better classification of candidates for DAA-based treatment.