A defined roadmap of radial glia and astrocyte differentiation from human pluripotent stem cells.

Human gliogenesis remains poorly understood, and derivation of astrocytes from human pluripotent stem cells (hPSCs) is inefficient and cumbersome. Here, we report controlled glial differentiation from hPSCs that bypasses neurogenesis, which otherwise precedes astrogliogenesis during brain development and in vitro differentiation. hPSCs were first differentiated into radial glial cells (RGCs) resembling resident RGCs of the fetal telencephalon, and modulation of specific cell signaling pathways resulted in direct and stepwise induction of key astroglial markers (NFIA, NFIB, SOX9, CD44, S100B, glial fibrillary acidic protein [GFAP]). Transcriptomic and genome-wide epigenetic mapping and single-cell analysis confirmed RGC-to-astrocyte differentiation, obviating neurogenesis and the gliogenic switch. Detailed molecular and cellular characterization experiments uncovered new mechanisms and markers for human RGCs and astrocytes. In summary, establishment of a glia-exclusive neural lineage progression model serves as a unique serum-free platform of manufacturing large numbers of RGCs and astrocytes for neuroscience, disease modeling (e.g., Alexander disease), and regenerative medicine.

Scalable generation of sensory neurons from human pluripotent stem cells.

Development of new non-addictive analgesics requires advanced strategies to differentiate human pluripotent stem cells (hPSCs) into relevant cell types. Following principles of developmental biology and translational applicability, here we developed an efficient stepwise differentiation method for peptidergic and non-peptidergic nociceptors. By modulating specific cell signaling pathways, hPSCs were first converted into SOX10+ neural crest, followed by differentiation into sensory neurons. Detailed characterization, including ultrastructural analysis, confirmed that the hPSC-derived nociceptors displayed cellular and molecular features comparable to native dorsal root ganglion (DRG) neurons, and expressed high-threshold primary sensory neuron markers, transcription factors, neuropeptides, and over 150 ion channels and receptors relevant for pain research and axonal growth/regeneration studies (e.g., TRPV1, NAV1.7, NAV1.8, TAC1, CALCA, GAP43, DPYSL2, NMNAT2). Moreover, after confirming robust functional activities and differential response to noxious stimuli and specific drugs, a robotic cell culture system was employed to produce large quantities of human sensory neurons, which can be used to develop nociceptor-selective analgesics.

Evaluation of Mitral-Aortic Flow Velocity Integral Ratio as a Tool to Differentiate Between Severe and Nonsevere Mitral Regurgitation.

OBJECTIVES: To evaluate mitral-aortic flow velocity integral ratio (MAVIR) as an echocardiographic tool to differentiate between severe and nonsevere mitral regurgitation (MR), compared with regurgitant volume (RVol) and effective regurgitant orifice area (EROA), with subgroup analysis in patients with calcific mitral valve, both by transthoracic (TTE) and transesophageal (TEE) echocardiography. Also, whether MAVIR can be used as a screening tool for severe MR. DESIGN: Prospective, cross-sectional, observational. SETTING: Cardiac operating room of a tertiary-care hospital. PARTICIPANTS: One hundred adult patients with chronic mitral regurgitation with at least mild MR by two-dimensional Doppler and with absence of mitral stenosis, aortic valve disease, and rhythm other than sinus scheduled for cardiac surgery. The subgroup (n = 24) consisted specifically of patients with a calcific mitral valve. INTERVENTIONS: Preinduction TTE and postinduction TEE in the operating room. MEASUREMENTS AND RESULTS: MAVIR, RVol, and EROA were measured in all patients both by TTE and TEE. Cohen's kappa statistics was employed to quantify concordance among RVol, EROA, and MAVIR. Diagnostic indices of MAVIR toward diagnosis of severe MR also were quantified. The results showed a strong agreement, in differentiating severe from nonsevere MR, between MAVIR and both RVol and EROA in the whole cohort (n = 100) and the subgroup (n = 24), both by TTE and TEE. Diagnostic indices were high for MAVIR compared with RVol and EROA in detecting severe MR, both by TTE and TEE. CONCLUSION: MAVIR may be used as an echocardiographic tool to differentiate between severe and nonsevere MR, even in patients with calcific valves. It also can be used to screen patients for severe MR.

Comparison Among Ultrasound-Guided Thoracic Paravertebral Block, Erector Spinae Plane Block and Serratus Anterior Plane Block for Analgesia in Thoracotomy for Lung Surgery.

BACKGROUND: To compare the analgesic efficacy and safety of preoperative, single-shot ultrasound-guided thoracic paravertebral block (TPVB), erector spinae plane block (ESB), and serratus anterior plane block (SAPB) in thoracotomy pain. DESIGN: A prospective, randomized study. SETTING: The cardiothoracic operating room and intensive care unit of a tertiary-care hospital in India. PARTICIPANTS: Ninety adult patients scheduled to undergo posterolateral thoracotomy for lung surgery under general anesthesia were recruited and randomized into 3 equal groups. INTERVENTIONS: Preoperatively, the patients received ultrasound-guided, single-shot nerve blocks within their respective groups, as follows: Erector spinae plane block in the ESB group, Thoracic paravertebral block in the TPVB group, and Serratus anterior plane block in the SAPB group. MEASUREMENTS AND RESULTS: The primary outcome measure, the visual analog scale (VAS) score, was recorded postoperatively in the intensive care unit at 0, 3, 6, 12, and 24 hours. The secondary outcome measures were the time to first rescue analgesic, total rescue opioid dose used, patient satisfaction at 24 hours, success of one-time attempt, and occurrence of adverse events. Data were statistically analyzed and a significant difference was found in the VAS score at all time points, the time to rescue analgesic and total opioid dosage, and patient satisfaction level (p < 0.05) among the groups with only 1 incidence of hypotension in the TPVB group. From post hoc analysis, ESB was found to have better analgesic efficacy compared with TPVB and SAPB. Serratus anterior plane block was found to be least efficacious and shortest acting among the three. CONCLUSION: The nerve blocks in decreasing order of analgesic efficacy in relieving post-thoracotomy pain would be ESB, TPVB, and SAPB.

SFPQ rescues F508del-CFTR expression and function in cystic fibrosis bronchial epithelial cells.

Cystic fibrosis (CF) occurs as a result of mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene, which lead to misfolding, trafficking defects, and impaired function of the CFTR protein. Splicing factor proline/glutamine-rich (SFPQ) is a multifunctional nuclear RNA-binding protein (RBP) implicated in the regulation of gene expression pathways and intracellular trafficking. Here, we investigated the role of SFPQ in the regulation of the expression and function of F508del-CFTR in CF lung epithelial cells. We find that the expression of SFPQ is reduced in F508del-CFTR CF epithelial cells compared to WT-CFTR control cells. Interestingly, the overexpression of SFPQ in CF cells increases the expression as well as rescues the function of F508del-CFTR. Further, comprehensive transcriptome analyses indicate that SFPQ plays a key role in activating the mutant F508del-CFTR by modulating several cellular signaling pathways. This is the first report on the role of SFPQ in the regulation of expression and function of F508del-CFTR in CF lung disease. Our findings provide new insights into SFPQ-mediated molecular mechanisms and point to possible novel epigenetic therapeutic targets for CF and related pulmonary diseases.

Comparative analyses of long non-coding RNA profiles in vivo in cystic fibrosis lung airway and parenchyma tissues.

BACKGROUND: Recent advances in the functional analyses of endogenous non-coding RNA (ncRNA) molecules, including long non-coding RNAs (LncRNAs), have provided a new perspective on the crucial roles of RNA in gene regulation. Consequently, LncRNA deregulation is a key factor in various diseases, including pulmonary disorders like Cystic Fibrosis (CF). CF is the most common life limiting recessive disease in the U.S., and is due to mutations in the CFTR gene. CF mutations, of which the most common is F508del-CFTR, prevents correct folding, trafficking and function of the mutant CFTR protein and is further manifested by the hyper-expression of pro-inflammatory cytokines and chemokines into the airway lumen leading to bronchiectasis and culminating in lung destruction. METHODS: Here we report a distinct LncRNA signature and corresponding mRNAs that distinguishes CF lung (airway and parenchyma) tissues from matched non-CF controls (n = 4 each group), generated by microarray specific for LncRNAs which includes corresponding mRNA expressions. In silico analyses of the cellular processes that are impacted by these LncRNAs was performed using Gene Ontology (GO). A selected subset of LncRNAs were validated by quantitative real-time PCR. RESULTS: We have identified 636 LncRNAs differentially expressed in CF airway epithelium and 1974 in CF lung parenchyma compared to matched non-CF controls (fold change ≥2, p < 0.05), majority of which (> 50%) are intergenic. Interestingly, 15 of these differentially expressed LncRNAs and 9 coding mRNAs are common to airway and parenchyma tissues. GO analyses indicates that signaling pathways and cell membrane functions are significantly affected by the alteration in LncRNA expressions in CF lung tissues. Seven of the differentially expressed LncRNAs, exhibit similar expression trends in CFBE41o- compared to control cells. CONCLUSION: Understanding the mechanisms by which these LncRNAs regulate CF disease phenotype will help develop novel therapeutic targets for CF and related pulmonary diseases, such as COPD and Asthma.

Is elevated blood glucose a marker of occult tissue hypoperfusion in off-pump coronary artery bypass grafting?

CONTEXT: Hyperglycemia has been found to occur during myocardial infarction and cardiac surgery even in nondiabetic patients. These being essentially stressful processes associated with hypoperfusion, we decided to find a possible relationship between the occurrence of global tissue hypoperfusion (GTH) and elevated blood glucose level in adult nondiabetic patients undergoing elective off-pump coronary artery bypass grafting (CABG). AIMS: This study aims to observe for the occurrence of global tissue hypoperfusion and its effect on blood glucose level and whether raised blood glucose level can be used as a marker for GTH. DESIGN: Prospective, observational study. SETTINGS: Cardiothoracic operation theater and intensive care unit of a tertiary care teaching hospital. MATERIALS AND METHODS: The occurrence of global tissue hypoperfusion were detected with the help of combined markers of mixed venous oxygen saturation and arterial lactate level at various perioperative study points together with arterial blood glucose level. Blood glucose level compared between the patients with and without GTH. STATISTICAL ANALYSIS USED: Numerical variables were compared between groups by Student's t-test and categorical variables by Fisher's exact test. Two-tailed P ≤ 0.05 was considered for statistically significant. RESULTS: The incidence of GTH was 67%. Blood glucose level was raised in patients with GTH at some study time points but with poor sensitivity and specificity values. CONCLUSIONS: Global tissue hypoperfusion is a common occurrence in even nondiabetic patients undergoing elective off-pump CABG. A relationship exists between rise in blood glucose level and global tissue hypoperfusion in such patients, although it cannot be viewed as marker of the same.

Prophylactic amiodarone vs dronedarone for prevention of perioperative arrhythmias in offpump coronary artery bypass grafting: A pilot randomized controlled trial.

The aim of this study was to compare the effects of prophylactic dronedarone and amiodarone in prevention of arrhythmias during and following off-pump coronary artery bypass grafting (OPCAB). This randomized, controlled, double-blinded, parallel-group study was carried out on 36 adult male patients aged 30-70 years, with modified Parsonnet score 0-10 undergoing offpump coronary artery bypass grafting. After obtaining approval from the institutional ethics committee and informed consent, the patients were randomly allocated to two equal groups (n=18). In one group, patients were given inj. amiodarone 3mg/kg in 100ml of normal saline prior to skin incision intravenously over 20 minutes. In the second group patients received tablet dronedarone 400mg orally twice daily, commencing three days prior to the date of surgery. Patients in the amiodarone group received placebo tablet while patients in the dronedarone group received placebo infusion for the sake of blinding. The frequency and profile of arrhythmias intraoperatively and 24 hours postoperatively were studied. Intraoperative arrhythmias occurred in 50% of patients receiving amiodarone and 16.67% of patients receiving dronedarone. Maximum ventricular rate during atrial fibrillation was significantly lower in the dronedarone group (121 beats per min) than in the amiodarone group (168 beats per min). The study concludes that dronedarone appears to be at least as effective as amiodarone in prophylaxis of intraoperative and postoperative arrhythmias in patients undergoing OPCAB, with a better control of ventricular response.

Effect of Vitamin C on adrenal suppression by etomidate induction in patients undergoing cardiac surgery: A randomized controlled trial.

INTRODUCTION: Etomidate is usually preferred in the induction of cardiac compromised patients due to its relative cardiovascular stability. However, the use of this drug has been limited as etomidate induces suppression of cortisol biosynthesis as a result of blockade of 11-beta-hydroxylation in the adrenal gland, mediated by the imidazole radical of etomidate. This study was carried out to observe the effect of Vitamin C on adrenal suppression after etomidate induction in patients undergoing cardiac surgery. MATERIALS AND METHODS: A total of 78 patients were randomly distributed into two groups. Group-I received oral Vitamin C (500 mg) twice daily and Group-II received antacid tablet as placebo twice daily instead of Vitamin C for 7 consecutive days prior to surgery till morning of surgery. Patients of both the groups induced with etomidate (0.1-0.3 mg/kg). Blood cortisol was estimated at different points of time till 24 th postinduction hour/blood lactate, glucose, hemodynamic parameters, and perioperative outcomes were assessed. RESULTS: Data of seventy patients (n = 35 in each group) were finally analyzed. Cortisol level is statistically significantly higher in Group-I (69.51 ± 7.65) as compared to Group-II (27.74 ± 4.72) (P < 0.05) in the 1 st postinduction hour. In Group-II, cortisol was consistently lower for 1 st 24 postinduction hour. Total adrenaline requirement was statistically significantly high in Group-II. Time of extubation, length of Intensive Care Unit stay arrhythmia was similar in both the groups. CONCLUSION: Vitamin C effectively inhibits etomidate-induced adrenal suppression in cardiac patients, thereby etomidate can be used as a safe alternative for induction in cardiac surgery under cardiopulmonary bypass when pretreated with Vitamin C.