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Background@#Xylazole (Xyl) is a veterinary anesthetic that is structurally and functionally similar to xylazine. However, the effects of Xyl in vitro remain unknown. @*Objectives@#This study aimed to investigate the anesthetic mechanism of Xyl using fetal rat nerve cells treated with Xyl. @*Methods@#Fetal rat nerve cells cultured for seven days were treated with 10, 20, 30, and 40 μg/ mL Xyl for 0, 5, 10, 15, 20, 25, 30, 45, 60, 90, and 120 min. Variations of amino acid neurotransmitters (AANTs), Nitric oxide-Cyclic GMP (NO-cGMP) signaling pathway, and ATPase were evaluated. @*Results@#Xyl decreased the levels of cGMP and NO in nerve cells. Furthermore, Xyl affected the AANT content and Na+ -K+ -ATPase and Ca2+ -Mg2+ -ATPase activity in nerve cells. These findings suggested that Xyl inhibited the NO-cGMP signaling pathway in nerve cells in vitro. @*Conclusions@#This study provided new evidence that the anesthetic and analgesic effects of Xyl are related to the inhibition of the NO-cGMP signaling pathway.
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Purpose@#Fractionated radiotherapy as well as concomitant and adjuvant chemotherapy such astemozolomide for postoperative high-grade glioma (HGG) patients improves progressionfreesurvival and overall survival. Multiple factors such as chemotherapy, radiotherapy,tumor grade, residual tumor volume, and genetic modifications might play a role in the formationof cognitive impairment. The risk factors of cognitive impairment in postoperativepatients with HGG receiving radiotherapy and chemotherapy remains a concern in this population.The purpose of this study was to identify risk factors for cognitive impairment inpatients of postoperative HGG. @*Materials and Methods@#A total of 229 patients with HGG who underwent surgery were analyzed. Cognitive impairmentwas defined as a decrease of Cognitive Assessment Montreal (MoCA)’s score in atleast two cognitive domains or any MoCA’s score of less than 26 points at the time of studycompared with baseline level. Multiple potential risk factors including methylated status ofthe O6-methylguanine-DNA methyltransferase (MGMT) promoter, glioma World HealthOrganization (WHO) grade, residual tumor volume, education, and sex were analyzed. Coxunivariate and multivariate regression analysis was used to detect the significant risk factorsfor cognitive impairment. @*Results@#At the end of follow-up among the 229 patients, 147 patients (67%) developed cognitiveimpairment. 82 patients (36%) remained in normal cognitive condition. In multivariate analysis,unmethylated MGMT promoter (hazard ratio [HR], 1.679; 95% confidence interval [CI],1.212 to 2.326; p=0.002), glioblastoma (HR, 1.550; 95% CI, 1.117 to 2.149; p=0.009),and residual tumor volume > 5.58 cm3 (HR, 1.454; 95% CI, 1.047 to 2.020; p=0.026) wereindependent risk factors for cognitive impairment. @*Conclusion@#Methylated status of the MGMT promoter, glioma WHO grade, and residual tumor volumemight be risk factors for the cognitive impairment in postoperative patients with HGG.