Differential regulation of bladder pain and voiding function by sensory afferent populations revealed by selective optogenetic activation

Bladder-innervating primary sensory neurons mediate reflex-driven bladder function under normal conditions, and contribute to debilitating bladder pain and/or overactivity in pathological states. The goal of this study was to examine the respective roles of defined subtypes of afferent neurons in bladder sensation and function in vivo via direct optogenetic activation. To accomplish this goal, we generated transgenic lines that express a Channelrhodopsin-2-eYFP fusion protein (ChR2-eYFP) in two distinct populations of sensory neurons: TRPV1-lineage neurons (Trpv1Cre;Ai32, the majority of nociceptors) and Nav1.8+ neurons (Scn10aCre;Ai32, nociceptors and some mechanosensitive fibers). In spinal cord, eYFP+ fibers in Trpv1Cre;Ai32 mice were observed predominantly in dorsal horn (DH) laminae I-II, while in Scn10aCre;Ai32 mice they extended throughout the DH, including a dense projection to lamina X. Fiber density correlated with number of retrogradely-labeled eYFP+ dorsal root ganglion neurons (82.2% Scn10aCre;Ai32 vs. 62% Trpv1Cre;Ai32) and degree of DH excitatory synaptic transmission. Photostimulation of peripheral afferent terminals significantly increased visceromotor responses to noxious bladder distension (30–50 mmHg) in both transgenic lines, and to non-noxious distension (20 mmHg) in Scn10aCre;Ai32 mice. Depolarization of ChR2+ afferents in Scn10aCre;Ai32 mice produced low- and high-amplitude bladder contractions respectively in 53% and 27% of stimulation trials, and frequency of high-amplitude contractions increased to 60% after engagement of low threshold (LT) mechanoreceptors by bladder filling. In Trpv1Cre;Ai32 mice, low-amplitude contractions occurred in 27% of trials before bladder filling, which was pre-requisite for light-evoked high-amplitude contractions (observed in 53.3% of trials). Potential explanations for these observations include physiological differences in the thresholds of stimulated fibers and their connectivity to spinal circuits

The factors associated with high-quality communication for critically ill children

OBJECTIVE: Timely, high quality communication with families is essential to family-centered decision-making. Quality communication is represented by widespread documentation of prognostic, goals-of-care conversations (PGOCC) in the pediatric intensive care unit (PICU) and should occur without variation by patient characteristics. METHODS: Cohort included 645 PICU admissions in the top decile of risk of mortality on admission over six years. Electronic medical records were used to determine PGOCC, diagnosis on admission and complex chronic condition (CCC) status. Multivariate logistic regression and time-to-event analyses were used. RESULTS: Overall, 31% had a documented PGOCC. 51% had CCC status. 11% had an oncologic, 13% had a cardiovascular diagnosis on admission. 94% of patients who died in the PICU had PGOCC documented, but among the 200 patients with documented PGOCC, 78% did not die in the PICU. Oncologic diagnosis on admission was associated with a higher likelihood of PGOCC compared to non-CCC patients (ARR=1.86; SE=0.26) whereas no other diagnosis category reached the level of statistical significance. Median time from admission to PGOCC was 2 days. Age, gender and CCC status were not associated with whether a PGOCC was documented or with time from admission to PGOCC documentation. 45% of PGOCC in the cohort and 50% of conversations in patients with CCC were documented by PICU physicians. CONCLUSIONS: This study reveals the opportunity for improvement in documentation of PGOCC for critically ill children. It raises the questions of why there is variation of PGOCC across disease categories and whether PGOCC should be considered a quality measure for family-centered care

DRUG-NEM: Optimizing drug combinations using single-cell perturbation response to account for intratumoral heterogeneity.

An individual malignant tumor is composed of a heterogeneous collection of single cells with distinct molecular and phenotypic features, a phenomenon termed intratumoral heterogeneity. Intratumoral heterogeneity poses challenges for cancer treatment, motivating the need for combination therapies. Single-cell technologies are now available to guide effective drug combinations by accounting for intratumoral heterogeneity through the analysis of the signaling perturbations of an individual tumor sample screened by a drug panel. In particular, Mass Cytometry Time-of-Flight (CyTOF) is a high-throughput single-cell technology that enables the simultaneous measurements of multiple ([Formula: see text]40) intracellular and surface markers at the level of single cells for hundreds of thousands of cells in a sample. We developed a computational framework, entitled Drug Nested Effects Models (DRUG-NEM), to analyze CyTOF single-drug perturbation data for the purpose of individualizing drug combinations. DRUG-NEM optimizes drug combinations by choosing the minimum number of drugs that produce the maximal desired intracellular effects based on nested effects modeling. We demonstrate the performance of DRUG-NEM using single-cell drug perturbation data from tumor cell lines and primary leukemia samples