Dietary and species influence on potential of plasma to stimulate differentiation and lipid accumulation in cultured adipocyte precursors

Sera and plasma from different species and from rats of various dietary statuses were compared with regard to effects on proliferation, glycerophosphate dehydrogenase (GPDH) activity, and lipid-filing of rat adipocyte precursors converting to adipocytes in primary cell culture. All of the tested sera and plasma samples were comparably supportive of cell multiplication, but their effects on elevation of GPDH activity (a key event in adipocyte differentiation) and lipid-filling varied greatly. Plasma supported a much greater increase in GPDH activity than serum, while serum from cats supported a much lower increase than serum from humans, calves, goats, or rats. Dietary status of rats did not affect the potential of plasma to support GPDH activity, but did affect plasma support of lipid-filing. A higher than normal degree of lipid-filling was promoted by plasma from rats fed a high-fat, high-sugar diet, while a lower than normal degree was promoted by plasma from fasted rats. Lipid-filling was also found to vary in response to changes in content of very low density lipoprotein (VLDL) in human plasma. This suggests that the influence of diet on the potential of plasma to promote adipocyte lipid-filling may be mediated by the effect of diet on plasma VLDL. The absence of a diet-dependent effect of plasma either on multiplication of adipocyte precursors or on degree of elevation of GPDH activity leaves unresolved the mechanism by which diet affects adipocyte production in animals.     

Human papillomavirus seroprevalence in pregnant women following gender-neutral and girls-only vaccination programs in Finland: A cross-sectional cohort analysis following a cluster randomized trial

BackgroundCervical cancer elimination through human papillomavirus (HPV) vaccination programs requires the attainment of herd effect. Due to its uniquely high basic reproduction number, the vaccination coverage required to achieve herd effect against HPV type 16 exceeds what is attainable in most populations. We have compared how gender-neutral and girls-only vaccination strategies create herd effect against HPV16 under moderate vaccination coverage achieved in a population-based, community-randomized trial.Methods and findingsIn 2007–2010, the 1992–1995 birth cohorts of 33 Finnish communities were randomized to receive gender-neutral HPV vaccination (Arm A), girls-only HPV vaccination (Arm B), or no HPV vaccination (Arm C) (11 communities per trial arm). HPV16/18/31/33/35/45 seroprevalence differences between the pre-vaccination era (2005–2010) and post-vaccination era (2011–2016) were compared between all 8,022 unvaccinated women <23 years old and resident in the 33 communities during 2005–2016 (2,657, 2,691, and 2,674 in Arms A, B, and C, respectively). Post- versus pre-vaccination-era HPV seroprevalence ratios (PRs) were compared by arm. Possible outcome misclassification was quantified via probabilistic bias analysis. An HPV16 and HPV18 seroprevalence reduction was observed post-vaccination in the gender-neutral vaccination arm in the entire study population (PR₁₆ = 0.64, 95% CI 0.10–0.85; PR₁₈ = 0.72, 95% CI 0.22–0.96) and for HPV16 also in the herpes simplex virus type 2 seropositive core group (PR₁₆ = 0.64, 95% CI 0.50–0.81). Observed reductions in HPV31/33/35/45 seroprevalence (PR_31/33/35/45 = 0.88, 95% CI 0.81–0.97) were replicated in Arm C (PR_31/33/35/45 = 0.79, 95% CI 0.69–0.90).ConclusionsIn this study we only observed herd effect against HPV16/18 after gender-neutral vaccination with moderate vaccination coverage. With only moderate vaccination coverage, a gender-neutral vaccination strategy can facilitate the control of even HPV16. Our findings may have limited transportability to other vaccination coverage levels.Trial registrationClinicalTrials.gov number {"type":"clinical-trial","attrs":{"text":"NCT00534638","term_id":"NCT00534638"}}NCT00534638, https://clinicaltrials.gov/ct2/show/{"type":"clinical-trial","attrs":{"text":"NCT00534638","term_id":"NCT00534638"}}NCT00534638.