The anterior cingulate cortex (ACC) has recently been proposed as a key player in the representation of itch stimuli. However, to date, little is known about the contribution of specific ACC interneuron populations to itch processing. Using c-Fos immunolabeling and in vivo Ca²⁺ imaging, we reported that both histamine and chloroquine stimuli-induced acute itch caused a marked enhancement of vasoactive intestinal peptide (VIP)-expressing interneuron activity in the ACC. Behavioral data indicated that optogenetic and chemogenetic activation of these neurons reduced scratching responses related to histaminergic and non-histaminergic acute itch. Similar neural activity and modulatory role of these neurons were seen in mice with chronic itch induced by contact dermatitis. Together, this study highlights the importance of ACC VIP⁺ neurons in modulating itch-related affect and behavior, which may help us to develop novel mechanism-based strategies to treat refractory chronic itch in the clinic.
Animals ; Pruritus/physiopathology* ; Vasoactive Intestinal Peptide/metabolism* ; Interneurons/metabolism* ; Gyrus Cinguli/metabolism* ; Mice ; Male ; Mice, Inbred C57BL ; Histamine ; Chloroquine ; Optogenetics ; Mice, Transgenic

Objective To investigate the effect of ultrasound-guided quadratus lumborum block on cognitive function after laparoscopic colorectal surgery.Methods Seventy-six patients, there is no restriction on gender, aged 50-75 years, falling into ASA physical statusⅡorⅢ, who provided informed consent for their participation in this study and underwent colorectal surgery under general anesthesia were divided into two groups (groups Q and C).Induction of anesthesia was induced by intravenous midazolam 0.03 mg/kg, sufentanil 0.5μg/kg, etomidate 0.3 mg/kg and rocuronium 1 mg/kg in the two groups.Remifentanil 0.2-0.3μg·kg-1·min-1 and propofol 0.10-0.15 mg·kg-1·min-1 were maintained intravenously during anesthesia.0.375％ropivacaine 20 ml was injected between the psoas quadratus muscle and psoas major muscle under ultrasound guidance before extubation in group Q, only equal volume saline was given in group C.Neuropsychological tests were performed preoperatively as well as postoperative day 7.The postoperative pain was evaluated by VAS after surgery.The postoperative sleep quality was measured using a BIS-vista monitor.The changes of serum IL-6, IL-1β, TNF-αand CGRP levels were detected by ELISA at immediately after operation (T0), 1 hour (T1), 2 days (T2), 4 days (T3) and 7 days (T4) after operation.Results Seventy-six patients finished cognitive function tests (38 cases in group Q and 38 cases in group C), 12 cases (31.6％) were diagnosed as POCD in group C, 4 cases (10.5％) in group Q.Compared with group C, the incidence of POCD, VAS scores at 24 and 48 hours after operation in group Q were significantly lower (P<0.05), the sleeping time at night was longer, the serum levels of IL-6, IL-1βand TNF-αwere significantly lower at T2 and T3, and the serum levels of CGRP were significantly higher at T2-T4 (P<0.05 or P<0.01).Conclusion QLB treatment repaired the surgery induced early cognitive dysfunction by inhibiting the postoperative pain, excessive inflammatory response and improving the quality of sleep.

Objective To explore the predictive capability of different methods for difficult la-ryngoscopy and analyze its optimal cutoff value.Methods Three hundred consecutive patients (aged 18-65 years,weighing 42-88 kg,ASA physical status Ⅰ or Ⅱ)scheduled to undergo general anesthe-sia and surgery were invited to participate.Difficult airway assessments were performed by thyromen-tal height (TMH),thyromental distance (TMD),sternomental distance (SMD),modified Mallam-pati test (MMT)and ratio of height and TMD (RHTMD)before anesthetic induction.Cormack-Le-hane (C-L)grade of laryngoscopy view was assessed after induction.Sensitivity,specificity,positive predictive value (PPV),negative predictive value (NPV)and accuracy of these tests were calculated. Receiver operator characteristic (ROC)curve of TMH was performed to determine the optimal cutoff value of TMH.Results There were 22 patients diagnosed as difficult airway.Sensitivity,specificity, PPV,NPV and accuracy of TMH were higher than those of TMD,SMD and MMT tests.Sensitivity of RHTMD was lower than that of TMH test,and specificity,PPV,NPV and accuracy of RHTMD were similar to that of TMH.The optimal cutoff value of TMH was 4.9 cm through ROC curve. Conclusion The optimal cutoff value of TMH detecting difficult laryngoscopy was 4.9 cm.Similar to RHTMD,TMH appears to be more effective for prediction of difficult laryngoscopy than TMD, SMD and MMT.

Objective To investigate the influence of low-dose ketamine and dexmedetomidine on cardiovascular response during. sedative amnesia fiberoptic nasotracheal intubation. Methods Ninety ASA Ⅰ or Ⅱ patients scheduled to recerve general anesthesia were evenly random-ized to dexmedetomidine and ketamine (group DK),dexmedetomidine and propofol (group DP)and dexmedetomidine and remifentanil (group DR).Ten minutes before intubation,the patients in group DK received intravenously dexmedetomidine 1.0 μg/kg plus ketamine 0.5 mg·kg-1 ·h-1 ;those in group DP received intravenously dexmedetomidine 1.0 μg/kg plus propofol 2.0 mg · kg-1 · h-1 ;those in group DR received intravenously dexmedetomidine 1.0 μg/kg plus remifentanil 5.0μg·kg-1 ·h-1 .Nasotracheal intubation was performed with fiberoptic bronchoscopy after dexemeto-midine injection and complete topical anesthesia.HR,MAP,SpO 2 and Ramsay sedation score were re-corded before anesthesia (T0 ,baseline),before intubation (T1 ),immediately intubated (T2 )and five minutes after intubation (T3 ).Side effects such as restlessness,bucking,respiratory depression and cardiovascular event during intubation and awareness of intubation were also recorded.Results All pa-tients in three groups were performed successfully.HR and MAP were significantly decreased in groups DP and DR at T1 (P <0.05),SpO 2 was significantly decreased in group DP at T1 (P <0.05);MAP in group DR were higher than those in group DP,HR in groups DP and DR were significantly increased than those in group DK at T3 (P < 0.05 );Ramsay score were significantly decreased in groups DP and DR at T2 ,significantly lower in group DR at T3 than those in groups DK and DP (P<0.05).The incidences of bradycardia and respriatory depression were significantly higher in group DP than those in group DK,and bucking,restlessness,tachycardia incidence rate in group DR were significantly higher than those in groups DK and DP (P <0.05).Conclusion Dexmedetomidine com-bined with low dose ketamine together with topical anesthesia is an ideal method for sedative amnesia fiberoptic nasotracheal intubation with slighter cardiovascular response and less side effects.