One of the mechanisms by which epithelial cells regulate intracellular pH is exchanging bicarbonate for Cl − . We tested the hypothesis that in ameloblasts the anion exchanger-2 (Ae2) is involved in pH regulation during maturation stage amelogenesis. Quantitative X-ray microprobe mineral content analysis, scanning electron microscopy, histology, micro-computed tomography and Ae2 immunolocalisation analyses were applied to Ae2-deficient and wild-type mouse mandibles. Immunolocalisation of Ae2 in wild-type mouse incisors showed a very strong expression of Ae2 in the basolateral membranes of the maturation stage ameloblasts. Strikingly, zones of contiguous ameloblasts were found within the maturation stage in which Ae2 expression was extremely low as opposed to neighbouring cells. Maturation stage ameloblasts of the Ae2 a,b −/− mice failed to stain for Ae2 and showed progressive disorganisation as enamel development advanced. Maturation stage enamel of the Ae2 a,b −/− mice contained substantially less mineral and more protein than wild-type enamel as determined by quantitative X-ray microanalysis. Incisor enamel was more severely affected than molar enamel. Scanning electron microscopy revealed that the rod-inter-rod structures of the Ae2 a,b −/− mice incisor enamel were absent. Mineral content of dentine and bone of Ae2 a,b −/− mice was not significantly different from wild-type mice. The enamel from knockout mouse teeth wore down much faster than that from wild-type litter mates. Basolateral bicarbonate secretion via the anionic exchanger Ae2 is essential for mineral growth in the maturation stage enamel. The observed zonal expression of Ae2 in the maturation stage ameloblasts is in line with a model for cyclic proton secretion during maturation stage amelogenesis.

Phospholipase A2, group XVI (PLA2G16) is a thiol hydrolase from the HRASLS family that regulates lipolysis in adipose tissue and has been identified as a host factor enabling the cellular entry of picornaviruses. Chemical tools are essential to visualize and control PLA2G16 activity, but they have not been reported to date. Here, we show that MB064, which is a fluorescent lipase probe, also labels recombinant and endogenously expressed PLA2G16. Competitive activity-based protein profiling (ABPP) using MB064 enabled the discovery of α-ketoamides as the first selective PLA2G16 inhibitors. LEI110 was identified as a potent PLA2G16 inhibitor (Ki = 20 nM) that reduces cellular arachidonic acid levels and oleic acid-induced lipolysis in human HepG2 cells. Gel-based ABPP and chemical proteomics showed that LEI110 is a selective pan-inhibitor of the HRASLS family of thiol hydrolases (i.e., PLA2G16, HRASLS2, RARRES3 and iNAT). Molecular dynamic simulations of LEI110 in the reported crystal structure of PLA2G16 provided insight in the potential ligand–protein interactions to explain its binding mode. In conclusion, we have developed the first selective inhibitor that can be used to study the cellular role of PLA2G16.

Purpose: To provide a nationally representative description on the prevalences of policies, practices, programs, and supports relating to worksite wellness in US hospitals. Design: Cross-sectional, self-report of hospitals participating in Workplace Health in America (WHA) survey from November 2016 through September 2017. Setting: Hospitals across the United States. Participants: Random sample of 338 eligible hospitals participating in the WHA survey. Measures: We used previous items from the 2004 National Worksite Health Promotion survey. Key measures included presence of Worksite Health Promotion programs, evidence-based strategies, health screenings, disease management programs, incentives, work-life policies, barriers to health promotion program implementation, and occupational safety and health. Analysis: Independent variables included hospital characteristics (eg, size). Dependent characteristics included worksite health promotion components. Descriptive statistics and χ2 analyses were used. Results: Eighty-two percent of hospitals offered a wellness programs during the previous year with larger hospitals more likely than smaller hospitals to offer programs ( P < .01). Among hospitals with wellness programs, 69% offered nutrition programs, 74% offered physical activity (PA) programs, and 84% had a policy to restrict all tobacco use. Among those with cafeterias or vending machines, 40% had a policy for healthier foods. Only 47% and 25% of hospitals offered lactation support or healthy sleep programs, respectively. Conclusion: Most hospitals offer wellness programs. However, there remain hospitals that do not offer wellness programs. Among those that have wellness programs, most offer supports for nutrition, PA, and tobacco control. Few hospitals offered programs on healthy sleep or lactation support.