Effect of Prenatal Lifestyle Intervention on Maternal Postpartum Weight Retention and Child Body MassIndex z-score at 36 Months

Background/Objectives We previously reported results from a randomized trial showing that a behavioral intervention during pregnancy reduced excess gestational weight gain but did not impact maternal weight at 12 months. We now examine the longer-term effects of this prenatal intervention on maternal postpartum weight retention and toddler body-mass-index z scores (BMIz) over 36 months. Subjects/Methods Pregnant women (N = 264; 13.7 weeks’ gestation; 41.6% Hispanic) with overweight or obesity were randomized into usual care or prenatal intervention. Anthropometric assessments in mothers and toddlers occurred at baseline, 35 weeks’ gestation and after delivery at 6, 12, 18, 24, and 36 months. Results At 36 months, prenatal intervention vs. usual care had no significant effect on the proportion of participants who returned to their early pregnancy weight or below (33.3% vs. 39.5%; p = 0.12) and had no effect on the magnitude of weight retained (2.8 [0.8, 4.8] vs 3.0 kg [1.0, 4.9], respectively; mean difference = 0.14 [−3.0, 2.7]). There was also no statistically significant intervention vs. usual care effect on infant BMIz or skinfold changes over time; toddler BMIz increased by 1.4 [−1.7, 1.0] units in the intervention group and 1.6 [−1.2, 1.8] units in the usual care group from delivery to 36 months (difference = 0.16 [−0.32. 0.63]). The proportion of toddlers at risk for obesity at 36 months was similar in intervention and usual care groups (28/77 [36.4%] vs 30/80 [37.5%]; p = 0.77). Conclusions Compared with usual care, lifestyle intervention during pregnancy resulted in similar maternal and toddler anthropometric outcomes at 36-months postpartum in a diverse US sample of women with overweight and obesity. To sustain improved maternal weight management initiated during pregnancy, continued intervention during the postpartum years may be needed

Metabolic causes of liver disease among adults living with HIV from low- and middle-income countries: a cross-sectional study.

INTRODUCTION Liver disease is a leading cause of morbidity and mortality among persons living with HIV (PLHIV). While chronic viral hepatitis has been extensively studied in low- and middle-income countries (LMICs), there is limited information about the burden of metabolic disorders on liver disease in PLHIV. METHODS We conducted a cross-sectional analysis of baseline data collected between October 2020 and July 2022 from the IeDEA-Sentinel Research Network, a prospective cohort enrolling PLHIV ≥40 years on antiretroviral treatment (ART) for ≥6 months from eight clinics in Asia, Americas, and central, East, southern and West Africa. Clinical assessments, laboratory testing on fasting blood samples and liver stiffness measurement (LSM)/controlled attenuation parameter (CAP) by vibration-controlled transient elastography were performed. Multivariable logistic regression models assessed factors associated with liver fibrosis (LSM ≥7.1 kPa) and steatosis (CAP ≥248 dB/m). Population attributable fraction (PAF) of each variable associated with significant liver fibrosis was estimated using Levin's formula. RESULTS Overall, 2120 PLHIV (56% female, median age 50 [interquartile range: 45-56] years) were included. The prevalence of obesity was 19%, 12% had type 2 diabetes mellitus (T2DM), 29% had hypertension and 53% had dyslipidaemia. The overall prevalence of liver fibrosis and steatosis was 7.6% (95% confidence interval [CI] 6.1-8.4) and 28.4% (95% CI 26.5-30.7), respectively, with regional variability. Male sex at birth (odds ratio [OR] 1.62, CI 1.10-2.40), overweight/obesity (OR = 2.50, 95% CI 1.69-3.75), T2DM (OR 2.26, 95% CI 1.46-3.47) and prolonged exposure to didanosine (OR 3.13, 95% CI 1.46-6.49) were associated with liver fibrosis. Overweight/obesity and T2DM accounted for 42% and 11% of the PAF for liver fibrosis, while HBsAg and anti-HCV accounted for 3% and 1%, respectively. Factors associated with steatosis included overweight/obesity (OR 4.25, 95% CI 3.29-5.51), T2DM (OR 2.06, 95% CI 1.47-2.88), prolonged exposure to stavudine (OR 1.69, 95% CI 1.27-2.26) and dyslipidaemia (OR 1.68, 95% CI 1.31-2.16). CONCLUSIONS Metabolic disorders were significant risk factors for liver disease among PLHIV in LMICs. Early recognition of metabolic disorders risk factors might be helpful to guide clinical and lifestyle interventions. Further prospective studies are needed to determine the causative natures of these findings

High-Density SNP Screening of the Major Histocompatibility Complex in Systemic Lupus Erythematosus Demonstrates Strong Evidence for Independent Susceptibility Regions

A substantial genetic contribution to systemic lupus erythematosus (SLE) risk is conferred by major histocompatibility complex (MHC) gene(s) on chromosome 6p21. Previous studies in SLE have lacked statistical power and genetic resolution to fully define MHC influences. We characterized 1,610 Caucasian SLE cases and 1,470 parents for 1,974 MHC SNPs, the highly polymorphic HLA-DRB1 locus, and a panel of ancestry informative markers. Single-marker analyses revealed strong signals for SNPs within several MHC regions, as well as with HLA-DRB1 (global p = 9.99×10−16). The most strongly associated DRB1 alleles were: *0301 (odds ratio, OR = 2.21, p = 2.53×10−12), *1401 (OR = 0.50, p = 0.0002), and *1501 (OR = 1.39, p = 0.0032). The MHC region SNP demonstrating the strongest evidence of association with SLE was rs3117103, with OR = 2.44 and p = 2.80×10−13. Conditional haplotype and stepwise logistic regression analyses identified strong evidence for association between SLE and the extended class I, class I, class III, class II, and the extended class II MHC regions. Sequential removal of SLE–associated DRB1 haplotypes revealed independent effects due to variation within OR2H2 (extended class I, rs362521, p = 0.006), CREBL1 (class III, rs8283, p = 0.01), and DQB2 (class II, rs7769979, p = 0.003, and rs10947345, p = 0.0004). Further, conditional haplotype analyses demonstrated that variation within MICB (class I, rs3828903, p = 0.006) also contributes to SLE risk independent of HLA-DRB1*0301. Our results for the first time delineate with high resolution several MHC regions with independent contributions to SLE risk. We provide a list of candidate variants based on biologic and functional considerations that may be causally related to SLE risk and warrant further investigation

Probenecid Inhibits the Human Bitter Taste Receptor TAS2R16 and Suppresses Bitter Perception of Salicin

Bitter taste stimuli are detected by a diverse family of G protein-coupled receptors (GPCRs) expressed in gustatory cells. Each bitter taste receptor (TAS2R) responds to an array of compounds, many of which are toxic and can be found in nature. For example, human TAS2R16 (hTAS2R16) responds to β-glucosides such as salicin, and hTAS2R38 responds to thiourea-containing molecules such as glucosinolates and phenylthiocarbamide (PTC). While many substances are known to activate TAS2Rs, only one inhibitor that specifically blocks bitter receptor activation has been described. Here, we describe a new inhibitor of bitter taste receptors, p-(dipropylsulfamoyl)benzoic acid (probenecid), that acts on a subset of TAS2Rs and inhibits through a novel, allosteric mechanism of action. Probenecid is an FDA-approved inhibitor of the Multidrug Resistance Protein 1 (MRP1) transporter and is clinically used to treat gout in humans. Probenecid is also commonly used to enhance cellular signals in GPCR calcium mobilization assays. We show that probenecid specifically inhibits the cellular response mediated by the bitter taste receptor hTAS2R16 and provide molecular and pharmacological evidence for direct interaction with this GPCR using a non-competitive (allosteric) mechanism. Through a comprehensive analysis of hTAS2R16 point mutants, we define amino acid residues involved in the probenecid interaction that result in decreased sensitivity to probenecid while maintaining normal responses to salicin. Probenecid inhibits hTAS2R16, hTAS2R38, and hTAS2R43, but does not inhibit the bitter receptor hTAS2R31 or non-TAS2R GPCRs. Additionally, structurally unrelated MRP1 inhibitors, such as indomethacin, fail to inhibit hTAS2R16 function. Finally, we demonstrate that the inhibitory activity of probenecid in cellular experiments translates to inhibition of bitter taste perception of salicin in humans. This work identifies probenecid as a pharmacological tool for understanding the cell biology of bitter taste and as a lead for the development of broad specificity bitter blockers to improve nutrition and medical compliance

PDRs4All III: JWST's NIR spectroscopic view of the Orion Bar

(Abridged) We investigate the impact of radiative feedback from massive stars on their natal cloud and focus on the transition from the HII region to the atomic PDR (crossing the ionisation front (IF)), and the subsequent transition to the molecular PDR (crossing the dissociation front (DF)). We use high-resolution near-IR integral field spectroscopic data from NIRSpec on JWST to observe the Orion Bar PDR as part of the PDRs4All JWST Early Release Science Program. The NIRSpec data reveal a forest of lines including, but not limited to, HeI, HI, and CI recombination lines, ionic lines, OI and NI fluorescence lines, Aromatic Infrared Bands (AIBs including aromatic CH, aliphatic CH, and their CD counterparts), CO2 ice, pure rotational and ro-vibrational lines from H2, and ro-vibrational lines HD, CO, and CH+, most of them detected for the first time towards a PDR. Their spatial distribution resolves the H and He ionisation structure in the Huygens region, gives insight into the geometry of the Bar, and confirms the large-scale stratification of PDRs. We observe numerous smaller scale structures whose typical size decreases with distance from Ori C and IR lines from CI, if solely arising from radiative recombination and cascade, reveal very high gas temperatures consistent with the hot irradiated surface of small-scale dense clumps deep inside the PDR. The H2 lines reveal multiple, prominent filaments which exhibit different characteristics. This leaves the impression of a "terraced" transition from the predominantly atomic surface region to the CO-rich molecular zone deeper in. This study showcases the discovery space created by JWST to further our understanding of the impact radiation from young stars has on their natal molecular cloud and proto-planetary disk, which touches on star- and planet formation as well as galaxy evolution.Comment: 52 pages, 30 figures, submitted to A&

Role of the Corneal Epithelial Basement Membrane in Ocular Defense against Pseudomonas aeruginosa▿

Pseudomonas aeruginosa can invade corneal epithelial cells and translocates multilayered corneal epithelia in vitro, but it does not penetrate the intact corneal epithelium in vivo. In healthy corneas, the epithelium is separated from the underlying stroma by a basement membrane containing extracellular matrix proteins and pores smaller than bacteria. Here we used in vivo and in vitro models to investigate the potential of the basement membrane to defend against P. aeruginosa. Transmission electron microscopy of infected mouse corneas in vivo showed penetration of the stroma by P. aeruginosa only where the basement membrane was visibly disrupted by scratch injury, suggesting that the intact basement membrane prevented penetration. This hypothesis was explored using an in vitro Matrigel Transwell model to mimic the corneal basement membrane. P. aeruginosa translocation of multilayered corneal epithelia grown on Matrigel was ∼100-fold lower than that of cells grown without Matrigel (P < 0.005, t test). Matrigel did not increase transepithelial resistance. Matrigel-grown cells blocked translocation by a P. aeruginosa protease mutant. Without cells, Matrigel also reduced traversal of P. aeruginosa and the protease mutant. Fluorescence microscopy revealed a relative accumulation of bacteria at the superficial epithelium of cells grown on Matrigel at 3 h compared to cells grown on uncoated filters. By 5 h, bacteria accumulated beneath the cells, suggesting direct trapping by the Matrigel. These findings suggest that the basement membrane helps defend the cornea against infection via physical barrier effects and influences on the epithelium and that these roles could be compromised by P. aeruginosa proteases

Individual differences in AMY1 gene copy number, salivary α-amylase levels, and the perception of oral starch.

The digestion of dietary starch in humans is initiated by salivary α-amylase, an endo-enzyme that hydrolyzes starch into maltose, maltotriose and larger oligosaccharides. Salivary amylase accounts for 40 to 50% of protein in human saliva and rapidly alters the physical properties of starch. Importantly, the quantity and enzymatic activity of salivary amylase show significant individual variation. However, linking variation in salivary amylase levels with the oral perception of starch has proven difficult. Furthermore, the relationship between copy number variations (CNVs) in the AMY1 gene, which influence salivary amylase levels, and starch viscosity perception has not been explored.Here we demonstrate that saliva containing high levels of amylase has sufficient activity to rapidly hydrolyze a viscous starch solution in vitro. Furthermore, we show with time-intensity ratings, which track the digestion of starch during oral manipulation, that individuals with high amylase levels report faster and more significant decreases in perceived starch viscosity than people with low salivary amylase levels. Finally, we demonstrate that AMY1 CNVs predict an individual's amount and activity of salivary amylase and thereby, ultimately determine their perceived rate of oral starch viscosity thinning.By linking genetic variation and its consequent salivary enzymatic differences to the perceptual sequellae of these variations, we show that AMY1 copy number relates to salivary amylase concentration and enzymatic activity level, which, in turn, account for individual variation in the oral perception of starch viscosity. The profound individual differences in salivary amylase levels and salivary activity may contribute significantly to individual differences in dietary starch intake and, consequently, to overall nutritional status

Factors Impacting Corneal Epithelial Barrier Function against Pseudomonas aeruginosa Traversal

Factors protecting the corneal epithelium against bacterial penetration were explored using a murine model. EGTA-dependent factors and surfactant protein D prevented bacterial penetration even when bacterial adherence and fluorescein staining were enabled by tissue paper blotting