The effect of sevoflurane exposure on cell-type-specific changes in the prefrontal cortex in young mice.

Sevoflurane, the predominant pediatric anesthetic, has been linked to neurotoxicity in young mice, although the underlying mechanisms remain unclear. This study focuses on investigating the impact of neonatal sevoflurane exposure on cell-type-specific alterations in the prefrontal cortex (PFC) of young mice. Neonatal mice were subjected to either control treatment (60% oxygen balanced with nitrogen) or sevoflurane anesthesia (3% sevoflurane in 60% oxygen balanced with nitrogen) for 2 hours on postnatal days (PNDs) 6, 8, and 10. Behavioral tests and single-nucleus RNA sequencing (snRNA-seq) of the PFC were conducted from PNDs 31 to 37. Mechanistic exploration included clustering analysis, identification of differentially expressed genes (DEGs), enrichment analyses, single-cell trajectory analysis, and genome-wide association studies (GWAS). Sevoflurane anesthesia resulted in sociability and cognition impairments in mice. Novel specific marker genes identified 8 distinct cell types in the PFC. Most DEGs between the control and sevoflurane groups were unique to specific cell types. Re-defining 15 glutamatergic neuron subclusters based on layer identity revealed their altered expression profiles. Notably, sevoflurane disrupted the trajectory from oligodendrocyte precursor cells (OPCs) to oligodendrocytes (OLs). Validation of disease-relevant candidate genes across the main cell types demonstrated their association with social dysfunction and working memory impairment. Behavioral results and snRNA-seq collectively elucidated the cellular atlas in the PFC of young male mice, providing a foundation for further mechanistic studies on developmental neurotoxicity induced by anesthesia.

For nasotracheal intubation, which nostril results in less epistaxis: right or left?: A systematic review and meta-analysis.

BACKGROUND: Nasotracheal intubation is usually required in patients undergoing oromaxillofacial, otolaryngological or plastic surgery to prevent the airway encroaching into the operating field. Epistaxis is the most common complication, but which nostril is associated with a lower incidence and severity of epistaxis is still unclear. OBJECTIVE: When both nostrils are patent, to determine the preferred nostril for nasotracheal intubation under general anaesthesia. DESIGN: A systematic review and meta-analysis of randomised controlled trials (RCTs). The primary outcome was the incidence of epistaxis and the secondary outcomes included the incidence of severe epistaxis, the time required to pass the tube through the nasal passage and total intubation time. DATA SOURCES: PubMed, Embase and the Cochrane Register of Controlled Trials were searched from database inception to 1 March 2020. ELIGIBILITY CRITERIA: The only studies included were RCTs comparing epistaxis related to nasotracheal intubation via right or left nostril, in adult surgery patients undergoing general anaesthesia. RESULTS: Ten RCTs with 1658 patients were included. Compared with the left nostril, intubation via the right nostril was associated with a significantly lower incidence of epistaxis: risk ratio (RR) and 95% confidence intervals (CI) were 0.78 (0.62 to 0.99), P = 0.04: a lower incidence of severe epistaxis (five studies, n=923), RR 0.40 (0.22 to 0.75), P = 0.004: and a shorter intubation time (three studies, n=345), mean difference -7.28 (-14.40 to -0.16) seconds, P = 0.05. In two studies (n=310), no significant difference between the right and left nostril was observed in the time to pass the tube through the nasal passages, mean difference -0.59 (-1.95 to 0.77) s, P = 0.40. CONCLUSION: On the basis of the current available evidence, when both nostrils are patent, the right nostril is more appropriate for nasotracheal intubation, with a lower incidence and severity of epistaxis and faster intubation time. TRIAL REGISTRATION: The study protocol has been registered in PROSPERO (CRD42020169949).

[Mutation analysis and prenatal diagnosis of FBN1 gene mutations for four patients with Marfan syndrome].

OBJECTIVE: To screen for mutations of fibrillin-1 (FBN1) gene in 4 patients with Marfan syndrome in order to provide prenatal diagnosis and genetic counseling. METHODS: Potential mutations of the FBN1 gene in the probands were detected with PCR and DNA sequencing. Subsequently, genomic DNA was extracted from amniotic fluid sampled between 18 to 20 weeks gestation. The mutations were confirmed with denaturing high-performance liquid chromatography - robust microsatellite instability (DHPLC-MSI) analysis with maternal DNA as reference. The products were further analyzed by direct sequencing and BLAST search of NCBI database. RESULTS: An IVS46+1G>A substitution was identified in patient A at +1 position of intron 46 of the FBN1 gene. Two novel missense mutations were respectively discovered at positions +4453 of intron 35 in patient B (Cys1485Gly) and position +2585 of intron 21 in patient C (Cys862Tyr). In patient D, a novel deletion (c.3536 delA) was found at position +3536 of intron 28. In all of the 4 cases, the same mutations have been identified in the fetuses. CONCLUSION: FBN1 gene analysis can provide accurate diagnosis of Marfan syndrome, which can facilitate both prenatal diagnosis and genetic counseling.

[Denaturing high-performance liquid chromatography coupled with multiplex PCR for rapid detection of large duplications or deletions in patients with Duchenne muscular dystrophy and spinal muscular atrophy].

OBJECTIVE: To assess the value of multiplex PCR-denaturing high-performance liquid chromatography (PCR-DHPLC) method for screening large duplications or deletions in patients with Duchenne muscular dystrophy (DMD) and spinal muscular atrophy (SMA). METHODS: DNA was extracted from peripheral venous blood samples from 35 DMD and 6 SMA patients. Large duplications or deletions were screened with multiplex PCR coupled with DHPLC method. The results were validated with testing of positive and negative controls. RESULTS: Known duplications or deletions in all controls were reliably detected with multiple PCR coupled with DHPLC. Large duplications or deletions were found in 71.4% of 35 DMD patients, which included 5 large duplications and 20 large deletions. For SMA patients, deletions of SMN1 exon 7 were detected in 16 samples. CONCLUSION: Multiplex PCR coupled with DHPLC method is an effective and reliable method for detecting large genomic duplications or deletions in patients with DMD or SMA.