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).

EGFR mutation status in plasma and tumor tissues in non-small cell lung cancer serves as a predictor of response to EGFR-TKI treatment.

OBJECTIVE: Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) can effectively control non-small cell lung cancer (NSCLC). Therefore, EGFR mutations should be detected before lung cancer patients undergo EGFR-TKI therapy. This study assessed the feasibility and predictive value of EGFR mutations in peripheral blood samples. METHODS: EGFR mutations in exons 19 and 21 were analyzed in tumor tissue and plasma DNA samples from 121 NSCLC patients using amplification refractory mutation system (ARMS) and the integrated technique of mutant enriched PCR (me-PCR) and denaturing high performance liquid chromatography (DHPLC), respectively. RESULTS: EGFR mutations were detected in 36.4% of tumor tissues and 34.7% of the plasma at a concordance rate of 85.1% (103/121). The sensitivity and specificity of plasma EGFR mutations were 77.3% and 89.6%, respectively. The gender and tumor histology of patients served as independent predictors of EGFR mutations in both tumor tissues and plasma, while CEA level was an independent predictor of EGFR mutations in the plasma. Furthermore, EGFR-TKI treatment showed a significantly higher objective response rate (ORR), median progression-free survival (mPFS), and overall survival (mOS) in patients harboring EGFR mutation than those that did not exhibit EGFR mutation (ORR: 69.4% versus 13.0% in tissues, P < 0.001; 64.5 % vs. 28.6% in the plasma, P = 0.006. mPFS: 10.4 months versus 4.1 months in tissues, P<0.001; 10.5 months vs. 5.2 months in the plasma, P=0.001. mOS: 25.7 months versus 8.3 months in tissues, P=0.005; 25.7 months vs. 13.5 months in the plasma, P=0.038). CONCLUSIONS: EGFR mutations can be detected in the plasma using the integrated technique of me-PCR and DHPLC, which enables us to predict patient response to EGFR-TKI therapy. High serum CEA levels served as an independent predictor for plasma EGFR mutations.

DNA repair gene ERCC1 C118T polymorphism predicts sensitivity of recurrent esophageal cancer to radiochemotherapy in a Chinese population.

BACKGROUND: DNA repair gene polymorphisms could alter DNA repair capacity and therefore associate with tumor sensitivity to radiochemotherapy. This study assessed excision repair cross-complementing group 1 (ERCC1) C118T and X-ray cross-complementing group 1 (XRCC1) G399A single-nucleotide polymorphisms in esophageal patients for an association with sensitivity to radiation and chemotherapy. METHODS: Esophageal squamous cell carcinoma patients (n = 118) who relapsed after surgery were enrolled for assessment of ERCC1 C118T and XRCC1 G399A polymorphisms by direct DNA sequencing. RESULTS: The response rate of treatments was 48.30%: 14 complete response (CR, 11.86%), 43 partial response (PR, 36.44%), 49 stable disease (SD, 41.53%), and 12 progressive disease (PD, 10.17%). ERCC1 C118T was significantly associated with treatment response (C/T vs. C/C + T/T, odds ratio [OR] = 6.035, 95% confidence interval [CI]: 2.114-17.226, P = 0.001) after adjusting for other clinicopathological factors. Patients carrying the C/T genotype had significantly prolonged overall survival (OS) compared with C/C and T/T (median OS 43.00 vs. 27.00, P = 0.027). Multivariate Cox regression showed that a response was only an independent prognostic factor for OS (CR + PR vs. SD+PD, HR = 0.471 95% CI 0.269-0.826, P = 0.009). Grade III and IV adverse events occurred in 12 of 118 patients (10.17%). Only concurrent radiochemotherapy significantly increased these adverse events (OR = 26.529, 95% CI 2.312-304.389, P = 0.008). CONCLUSION: ERCC1 C118T could be a predictive factor for the response to radiotherapy and chemotherapy, but not a prognostic factor for OS in esophageal cancer patients after surgery.

[Establishment of an allele-specific PCR method for direct screening of CYP21A2 gene mutation].

OBJECTIVE: To establish an allele-specific PCR method for detect screening of CYP21A2 gene mutation. METHODS: Allele-specific PCR primers and analogy primers were designed based on the sequence alignment of CYP21A2 and CYP21AP genes. Genomic DNA was extracted from blood specimens of 4 patients with 21-hydroxylase deficiency and 5 healthy controls and respectively amplified with allele-specific PCR primers and analogy primers and sequenced. RESULTS: Mutations of CYP21A2 including IVS2-13A/C>G, Arg356Trp and Arg149Pro were found with the established method in all of the 4 patients but not in the healthy controls. When detected with the analogy primers set, IVS2-13A/C>G and Arg356Trp were observed in both patients and healthy controls. CONCLUSION: The allele-specific PCR-based method is a simple, effective and reliable method for the detection of CYP21A2 gene mutation.

Prognostic value of the BRAF V600E mutation in papillary thyroid carcinoma.

The aim of the present study was to investigate the prevalence of the BRAF V600E mutation in papillary thyroid carcinoma (PTC) and to determine the correlation between this mutation and indicators of poor prognosis and outcome in patients with PTC. The BRAF V600E mutation status was analyzed in 187 tumor samples using the multiplex allele-specific PCR method. Univariate and multivariate analyses were performed to investigate the association of the BRAF V600E mutation with clinical features and patient outcome. The sensitivity of the multiplex allele-specific PCR combined with denaturing high-performance liquid chromatography reached ~1%. The BRAF V600E mutation was observed in 63.6% (119/187) of tumor tissues, predominantly in PTC specimens, and no BRAF mutation was identified in other benign-type thyroid diseases. The univariate analysis indicated that the BRAF V600E mutation was associated with age, tumor stage and prognosis (P<0.05). In addition, the frequency of the BRAF V600E mutation was significantly different in the central (75.3%) and lateral neck (49.3%) lymph nodes of patients with lymph node metastasis. Multivariate logistic regression analysis showed that the BRAF V600E mutation (HR, 2.471; 95% CI, 1.149-5.312) and lymph node metastasis (HR, 3.003; 95% CI, 1.027-8.771) are independent factors that predict tumor prognosis. Thus, the BRAF V600E mutation is an independent risk factor that may be used to predict thyroid cancer persistence/recurrence.

Identification of exon 19 and 21 mutations of EGFR gene in Chinese patients with esophageal squamous cell carcinoma.

BACKGROUND: Although epidermal growth factor receptor (EGFR) inhibitor treatment showed modest response in several clinical trials in esophageal squamous cell carcinoma (ESCC) patients, it has been reported that the frequency of EGFR mutations varied largely. The aim of this study was to investigate the existence of EGFR mutations in Chinese esophageal squamous cell carcinomas. METHODS: Formalin-fixed paraffin-embedded surgically resected tumor samples were obtained from 127 randomly selected Chinese patients with ESCC. The most common EGFR mutations, including in-frame deletions in exon 19 and base substitutions in exon 21, were detected by denaturing high performance liquid chromatography (DHPLC) and direct sequencing simultaneously. K-RAS mutations in codons 12 and 13 were detected by direct sequencing. RESULTS: In this study, L858R missense mutations of the EGFR gene were found in 8 out of 127 patients (6.3%) by DHPLC but no mutation was observed by direct sequencing. In addition, K-RAS mutation was detected in 2 out of 127 (1.6%) patients by direct sequencing. CONCLUSIONS: The incidence of EGFR mutations was relatively high using DHPLC method but no mutation with direct sequencing in Chinese ESCC patients.

[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.

Expressional and epigenetic alterations of placental matrix metalloproteinase 9 in preeclampsia.

Preeclampsia is classically defined by the presence of hypertension and proteinuria after 20 weeks gestation and, thus, affects multiple body systems. The etiology of the disease remains poorly understood but it is known that the expression profile of placental genes is modified, including that of several matrix metalloproteinases (MMPs). The objective of this study was to perform a systematic expression analysis of MMP9 genes in normal and pathological placentas, and to pinpoint epigenetic alterations inside the MMP9 promoter region. Placentas were obtained from 20 patients with preeclampsia and 18 normal pregnancies in the third trimester. The methylation status of the promoter regions of MMP9 was analyzed with methylation-sensitive restriction enzymes, followed by polymerase chain reaction amplification. Our study found significantly higher expression levels of MMP9 in placental sections from preeclampsia tissue and this increased expression was well correlated to promoter demethylation. The percentage of unmethylated -712 sites were higher in preeclampsia patients (90%) compared with controls (44%). In conclusion, this study provides evidence that altered synthesis of MMP9 in preeclampsia placentas may result from epigenetic changes of the methylation status of CpG sites in the promoter region.

Quercetin is able to demethylate the p16INK4a gene promoter.

BACKGROUND: Quercetin is a flavonoid found ubiquitously in nature. Studies in vitro and in vivo have suggested that quercetin may have a protective role against colon cancer. METHODS: We selected the human colon cancer cell line RKO to investigate the effects of quercetin in vitro. RKO cells were treated with different concentrations of quercetin. RESULTS: In comparison to the control, quercetin was able to inhibit the growth of RKO cells, as measured using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Untreated RKO cells demonstrated almost complete methylation of the p16INK4a gene. Hypermethylation of the p16INK4a gene was successfully reversed after 120 h of treatment with quercetin. Expression of the p16INK4a gene was restored in a concentration-dependent manner. CONCLUSION: All these data suggest that quercetin has antitumor properties, probably via demethylation of the p16INK4a gene promoter.

A novel mutation in AlphaA-crystallin (CRYAA) caused autosomal dominant congenital cataract in a large Chinese family.

Hereditary cataract is a phenotypically and genetically heterogeneous lens disease that is responsible for a significant proportion of the visual impairment and blindness that occurs in children. In a five-generation Chinese family with autosomal dominant inherited congenital cataract, clinical examination showed three cataract phenotypes: punctuate, nuclear, and total cataracts. Linkage analysis was performed and positive two-point LOD scores (with maximum of 4.43 and 4.27 at theta=0) were obtained for markers D21S1411 and D21S1890 on chromosome 21q22.3, flanking the CRYAA (alphaA-crystallin-encoding gene) locus. Sequencing of CRYAA revealed a novel heterozygous G>A transition (c.346G>A) in exon 3 that cosegregated with the disease phenotype and results in a conservative substitution of Arg to His at codon 116 (p.R116H). To understand the molecular basis of cataract formation, mutant and wild-type alphaA-crystallins were expressed in E. coli. RP-HPLC (reverse phase-high-performance liquid chromatography) suggested an increased hydrophobicity of the mutant recombinant protein, compared to that of wild-type alphaA-crystallins. Furthermore, loss of chaperone activity of the mutant was seen in DTT (DL-dithiothreitol)-induced insulin aggregation assay. FPLC (fast protein liquid chromatography) purification showed that the His-116 mutant protein had increased binding affinity to lysozyme. Gain of activated lysozyme binding, elevation of hydrophobicity and loss of chaperone activity of the mutant protein may be some of the molecular mechanisms underlying cataract in this large family.

Mutation G61C in the CRYGD gene causing autosomal dominant congenital coralliform cataracts.

PURPOSE: We sought to identify the genetic defect in a four-generation Chinese family with autosomal dominant congenital coralliform cataracts and demonstrate the functional analysis of a candidate gene in the family. METHODS: Family history data were recorded. Clinical and ophthalmologic examinations were performed on affected and unaffected family members. All the members were genotyped with microsatellite markers at loci considered to be associated with cataracts. Two-point LOD scores were calculated using the Linkage software after genotyping. A mutation was detected by direct sequencing, using gene-specific primers. Wild-type and mutant proteins were analyzed with online software. RESULTS: Affected members of this family had coralliform cataracts. Linkage analysis was obtained at markers, D2S72 (LOD score [Z]=3.31, recombination fraction [theta]=0.0) and D2S1782 (Z=3.01, theta=0.0). Haplotype analysis indicated that the cataract gene was closely linked to these two markers. Sequencing the gammaD-crystallin gene (CRYGD) revealed a G>T transversion in exon 2, which caused a conservative substitution of Gly to Cys at codon 61 (P.G61C). This mutation co-segregated with the disease phenotype in all affected individuals and was not observed in any of the unaffected or 100 normal, unrelated individuals. Bioinformatic analyses showed that a highly conserved region was located around Gly61. Data generated with online software revealed that the mutation altered the protein's stability, solvent-accessibility, and interactions with other proteins. CONCLUSIONS: This is the first reported case of a congenital coralliform cataract phenotype associated with the mutation of Gly61Cys (P.G61C) in the CRYGD gene; it demonstrates a possible mechanism of action for the mutant gene.