Publications

Pulmonary neuroendocrine cells (PNECs) are rare airway epithelial cells whose function is poorly understood. Here we show that -mutant mice that have no PNECs exhibit severely blunted mucosal type 2 response in models of allergic asthma. PNECs reside in close proximity to group 2 innate lymphoid cells (ILC2s) near airway branch points. PNECs act through calcitonin gene-related peptide (CGRP) to stimulate ILC2s and elicit downstream immune responses. In addition, PNECs act through the neurotransmitter γ-aminobutyric acid (GABA) to induce goblet cell hyperplasia. The instillation of a mixture of CGRP and GABA in -mutant airways restores both immune and goblet cell responses. In accordance, lungs from human asthmatics show increased PNECs. These findings demonstrate that the PNEC-ILC2 neuroimmunological modules function at airway branch points to amplify allergic asthma responses.

OBJECTIVE

Fibroblast growth factor 23 (FGF-23) may be involved in signaling between bone and adipose tissue in dialysis patients, but its role is uncertain. We sought to examine the association between FGF-23 and adiposity and whether this association is mediated in part by leptin.

DESIGN/SETTING

We performed univariate and multivariate linear regression analyses using data from 611 participants in a cohort of prevalent hemodialysis patients recruited from dialysis centers in Atlanta, GA and San Francisco, CA from 2009 to 2011. We also investigated the role of leptin in these relationships.

SUBJECTS

Participants were aged ≥18 years, English or Spanish speaking, and receiving hemodialysis for at least 3 months.

MAIN OUTCOME MEASURES

Outcome measures of adiposity included body mass index, waist circumference, and body fat measured by bioelectrical impedance spectroscopy.

RESULTS

Mean age was 56 ± 14 years, 39.8% were female, and median serum FGF-23 was 807 pg/mL. In fully adjusted models, FGF-23 was inversely associated with body mass index (-0.24 kg/m per 50% higher FGF-23, 95% confidence interval [CI]: -0.38 to -0.10), waist circumference (-0.44 cm per 50% higher FGF-23, 95% CI: -0.79 to -0.08), and percent body fat (-0.58% per 50% higher FGF-23, 95% CI: -0.79 to -0.37). Leptin was inversely associated with FGF-23. Addition of leptin to body composition models attenuated the associations between FGF-23 and measures of adiposity, but FGF-23 remained significantly associated with percent body fat (-0.17% per 50% higher FGF-23, 95% CI: -0.32 to -0.02).

CONCLUSION

We found a negative association between FGF-23 and adiposity that appears to be mediated in part by leptin. As adipose tissue provides a "protective energy depot" for patients with chronic illness, a decrease in adipose tissue may be one mechanism in which higher FGF-23 levels may contribute to increased mortality in dialysis patients.

BACKGROUND

Indwelling urethral catheters (IUC) are routinely inserted for the purpose of monitoring urine output in patients with acute heart failure (AHF). The benefit of IUC in patients capable of complying with urine collection protocols is unclear, and IUC carry multiple risks. This study describes the impact of IUC on AHF treatment.Methods and Results:A total of 540 records were retrospectively analyzed. After exclusion criteria were applied, 316 patients were propensity matched to establish groups of 100 AHF patients who either did (IUC(+)) or did not receive an IUC (IUC(-)) upon admission. Hospital length of stay (9 vs. 7 days), in-hospital urinary complications (24 vs. 5%), and 1-year urinary tract infection rate (17 vs. 6%; HR, 3.145; 95% CI: 1.240-7.978) were significantly higher in the IUC(+) group (P<0.05 for all). There were no differences in 30-day rehospitalization (6 vs. 6%; HR, 0.981; 95% CI: 0.318-3.058; P=0.986) or major adverse cardiac/cerebrovascular events at 1 year (37 vs. 32%, HR, 1.070; 95% CI: 0.636-1.799; P=0.798).

CONCLUSIONS

Based on this retrospective analysis, the routine use of IUC may increase length of stay and UTI complications in AHF patients without reducing the risk for major cardiovascular and cerebrovascular events or 30-day rehospitalization rate.

This month: protein-complex dynamics (Tan), how noise promotes cell survival (Goulian), multiplex cell-surface-protein detection (Wells), single-cell sequencing (Klein/Socolovsky, Ye), social networks of honeybees (Robinson), new synthetic devices (Liu, Cai), and controlling segmentation clock dynamics (Aulehla).