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Loss-of-function sequence variants in KCNA1, which encodes the voltage-gated potassium channel Kv1.1, cause Episodic Ataxia Type 1 (EA1) and epilepsy. Due to a paucity of drugs that directly rescue mutant Kv1.1 channel function, current therapeutic strategies for KCNA1-linked disorders involve indirect modulation of neuronal excitability. Native Americans have traditionally used conifer extracts to treat paralysis, weakness, and pain, all of which may involve altered electrical activity and/or Kv1.1 dysfunction specifically. Here, screening conifer extracts, we found that Chamaecyparis pisifera increases wild-type (WT) Kv1.1 activity, as does its prominent metabolite, the abietane diterpenoid pisiferic acid. Uniquely, pisiferic acid also restored function in 12/12 EA1-linked mutant Kv1.1 channels tested in vitro. Crucially, pisiferic acid (1 mg/kg) restored WT function in Kv1.1E283K/+ mice, a model of human EA1. Experimentally validated all-atom molecular dynamics simulations in a neuron-like membrane revealed that the Kv1.1 voltage-sensing domain (VSD) also acts as a ligand-binding domain akin to those of classic ligand-gated channels; binding of pisiferic acid induces a conformational shift in the VSD that ligand-dependently opens the pore. Conifer metabolite pisiferic acid is a promising and versatile therapeutic lead for EA1 and other Kv1.1-linked disorders.

Animals requiring purposeful movement for survival are endowed with mechanoreceptors, called proprioceptors, that provide essential sensory feedback from muscles and joints to spinal cord circuits, which modulates motor output. Despite the essential nature of proprioceptive signaling in daily life, the mechanisms governing proprioceptor activity are poorly understood. Here, we identified nonredundant roles for two voltage-gated sodium channels (NaVs), NaV1.1 and NaV1.6, in mammalian proprioception. Deletion of NaV1.6 in somatosensory neurons (NaV1.6cKO mice) causes severe motor deficits accompanied by loss of proprioceptive transmission, which contrasts with our previous findings using similar mouse models to target NaV1.1 (NaV1.1cKO). In NaV1.6cKO animals, we observed impairments in proprioceptor end-organ structure and a marked reduction in skeletal muscle myofiber size that were absent in NaV1.1cKO mice. We attribute the differential contributions of NaV1.1 and NaV1.6 to distinct cellular localization patterns. Collectively, we provide evidence that NaVs uniquely shape neural signaling within a somatosensory modality.

BackgroundClinical determination of patients at high risk of poor surgical outcomes is complex and may be supported by clinical tools to summarize the patient's own personalized electronic health record (EHR) history and vitals data through predictive risk models. Since prior models were not readily available for EHR-integration, our objective was to develop and validate a risk stratification tool, named the Assessment of Geriatric Emergency Surgery (AGES) score, predicting risk of 30-day major postoperative complications in geriatric patients under consideration for urgent and emergency surgery using pre-surgical existing electronic health record (EHR) data.MethodsPatients 65-years and older undergoing urgent or emergency non-cardiac surgery within 21 hospitals 2017-2021 were used to develop the model (randomly split: 80% training, 20% test). The primary outcome was a 30-day composite outcome including several postoperative major complications and mortality; secondary outcomes included common individual complications included in the primary composite outcome (sepsis, progressive renal insufficiency or renal failure, and mortality). Patients' EHR-based clinical history, vital signs, labs, and demographics were included in logistic regression, LASSO, decision tree, Random Forest, and XGBoost models. Area under the receiver operating characteristics curve (AUCROC) was used to compare model performance.ResultsOverall, 66,262 patients (median [IQR] age 78 [(70.9-84.0], female 53.9%, White race 68.5%) received urgent or emergency non-cardiac surgery (25.7% orthopedic cases, 21.9% general surgery cases). AUCROC ranged from 0.655 (Decision Tree) - 0.804 (XGBoost) for the primary composite outcome. XGBoost AUCROC was 0.823, 0.781, and 0.839 in predicting outcomes of sepsis, progressive renal insufficiency or renal failure, and mortality, respectively.ConclusionsWe developed a model to accurately predict major postoperative complications in geriatric patients undergoing urgent or emergency surgery using the patient's own existing EHR data. EHR implementation of this model could efficiently support clinicians' surgical risk assessment and perioperative decision-making discussions in this vulnerable patient population.

Stellate ganglion blockade (SGB) is a practical approach to managing many clinical disorders. Ultrasound-guided SGB is currently adopted as a more effective and safer method in humans. Developing this technique in rats would facilitate further study of SGB application. The present study examined physiological responses following ultrasound-guided SGB in Sprague-Dawley rats. Under general anesthesia, lidocaine containing Chicago blue dye (1.0%-1.5% in 40-60 µL) was injected into the unilateral stellate ganglion (SG). Ptosis was observed on the ipsilateral right (n = 8) or left (n = 7) side of lidocaine administration. No ptosis was noted in any controls by 0.9% normal saline injection into the right (n = 6) or left (n = 6) SG. Heart rate (HR) was significantly decreased after administration of lidocaine (344 ± 32 to 289 ± 47 bpm; p = 0.015, pre-vs. after-injection), but not after normal saline, into the right SG. HR was unaltered after injecting lidocaine or normal saline into the left SG. Heart rate variability analysis showed that SGB with lidocaine on the right or left side caused a decrease in the ratio of the power of low-frequency over high-frequency. Respiratory rate, body temperature, and general conditions were unchanged in all rats, regardless of left or right SGB. Chicago blue dye was confirmed to be distributed in the SG region. No bleeding or tissue damage was evident in the injected SG area. Our findings suggest that ultrasound-guided unilateral SGB effectively inhibits cervicothoracic sympathetic nerves in rats and enhances heart rate variability, and sympathetic nerves controlling HR are likely predominantly associated with the right SG in the rat.

Postoperative nausea and vomiting (PONV) are common complications following general anesthesia, particularly in gynecological laparoscopic surgeries. This study aims to evaluate the effect of intraoperative noise isolation on PONV incidence. This single-center, prospective, randomized controlled trial will enroll 192 adult patients undergoing laparoscopic gynecological surgery. Patients will be randomly assigned in a 1:1 ratio and stratified by age into either the control group (Group C), without noise-cancelling headphones, or a noise reduction group (Group NR), using noise-cancelling headphones from anesthesia induction until the end of surgery. All patients will receive intraoperative dexamethasone and ondansetron prophylaxis. The primary outcome is the incidence of PONV within 48 h post-surgery. Secondary outcomes include PONV severity at 24 and 48 h, antiemetic use, pain scores, need for rescue analgesia, Quality of Recovery-15 (QoR-15) scores, Richards-Campbell Sleep Questionnaire (RCSQ) scores, hemodynamic interventions, extubation time, length of stay in PACU and hospital, adverse events (hypertension, hypotension, bradycardia, tachycardia, desaturation after extubation, postoperative shivering, emergence agitation, allergic reactions, severe arrhythmias arrhythmia, cardiac arrest, hypothermia), patient satisfaction, and postoperative complications based on the Postoperative Morbidity Survey (POMS). Analyses will be conducted using modified intention-to-treat (mITT) and per-protocol (PP) populations. We hypothesize that intraoperative use of noise-cancelling headphones will reduce PONV incidence in patients undergoing gynecological laparoscopic surgery. The findings could enhance postoperative care protocols for thoracoscopic gynecological procedures. Chinese Clinical Trial Registry (ChiCTR2400087460).

The most severe form of α-thalassemia results from loss of all four copies of α-globin. Postnatally, patients face challenges similar to β-thalassemia, including severe anemia and erythrotoxicity due to the imbalance of β-globin and α-globin chains. Despite progress in genome editing treatments for β-thalassemia, there is no analogous curative option for α-thalassemia. To address this, we designed a Cas9/AAV6-mediated genome editing strategy that integrates a functional α-globin gene into the β-globin locus in α-thalassemia patient-derived hematopoietic stem and progenitor cells (HSPCs). Incorporation of a truncated erythropoietin receptor transgene into the α-globin integration cassette significantly increased erythropoietic output from edited HSPCs and led to the most robust production of α-globin, and consequently hemoglobin tetramers. By directing edited HSPCs toward increased production of clinically relevant erythroid cells, this approach has the potential to mitigate the limitations of current treatments for the hemoglobinopathies, including low genome editing and low engraftment rates.

SGLT2 inhibitors and GLP1 receptor agonists have kidney protective effects. By combining immunostaining-guided laser capture microdissection and RNA sequencing, the study established how the gene expression profile changes in SGLT2-positive proximal tubule cells in response to type 1 Akita diabetes and to pharmacological intervention by SGLT2 inhibition or GLP1R agonism and genetic deletion of SGLT1. The data also indicate genes unresponsive to those treatments that may include new therapeutical candidates.

BackgroundLong COVID patients present with a myriad of symptoms that can include fatigue, exercise intolerance and post exertional malaise (PEM). Long COVID has been compared to other post viral syndromes, including myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), where a reduction in day 2 cardiopulmonary exercise test (CPET) performance of a two-day CPET protocol is suggested to be a result of PEM. We investigated cardiopulmonary and perceptual responses to a two-day CPET protocol in Long COVID patients.Methods15 Long COVID patients [n=7 females; mean (SD) age: 53(11) yr; BMI = 32.2(8.5) kg/m2] performed a pulmonary function test and two ramp-incremental CPETs separated by 24 hr. CPET variables included gas exchange threshold (GET), peak oxygen uptake (V̇O2peak) and peak work rate (WRpeak). Ratings of perceived dyspnoea and leg effort were recorded at peak exercise using the modified 0-10 Borg Scale. PEM (past six months) was assessed using the modified DePaul Symptom Questionnaire (mDSQ). One-sample t-tests were used to test significance of mean difference between days (p0.05).ConclusionPEM symptoms in Long COVID patients, in the absence of differences in two-day CPET responses separated by 24 hours, suggests that PEM is not due to impaired recovery of exercise capacity between days.

Corticotropin-releasing hormone (CRH) signaling through its cognate receptors, CRHR1 and CRHR2, contributes to diverse stress-related functions in the mammalian brain. Whereas CRHR2 is predominantly expressed in choroid plexus and blood vessels, CRHR1 is abundantly expressed in neurons in discrete brain regions, including the neocortex, hippocampus and nucleus accumbens. Activation of CRHR1 influences motivated behaviors, emotional states, and learning and memory. However, it is unknown whether alterations in CRHR1 signaling contribute to aberrant motivated behaviors observed, for example, in stressful contexts. These questions require tools to manipulate CRHR1 selectively. Here we describe and validate a novel Crhr1-FlpO mouse. Using bacterial artificial chromosome (BAC) transgenesis, we engineered a transgenic mouse that expresses FlpO recombinase in CRHR1-expressing cells. We used two independent methods to assess the specificity of FlpO to CRHR1-expressing cells. First, we injected Crhr1-FlpO mice with Flp-dependent viruses expressing fluorescent reporter molecules. Additionally, we crossed the Crhr1-FlpO mouse with a transgenic Flp-dependent reporter mouse. CRHR1 and reporter molecules were identified using immunocytochemistry and visualized via confocal microscopy in several brain regions in which CRHR1 expression and function is established. Expression of Flp-dependent viral constructs was highly specific to CRHR1-expressing cells in all regions examined (over 90% co-localization). In accord, robust and specific expression of the Flp-dependent transgenic reporter was observed in a reporter mouse, recapitulating endogenous CRHR1 expression. The Crhr1-FlpO mouse enables selective genetic access to CRHR1-expressing cells within the mouse brain. When combined with Cre-lox or site-specific recombinases, the mouse facilitates intersectional manipulations of CRHR1-expressing neurons.