Our previous studies showed that cysteinyl leukotriene receptor-1 (CysLT₁) antagonist pranlukast has a neuroprotective effect on cerebral ischemia in rats and mice. However, whether the neuroprotective effect of pranlukast is its special action or a common action of CysLT₁ receptor antagonists remains to be clarified. This study was performed to determine whether montelukast, another CysLT₁ receptor antagonist, has the neuroprotective effect on focal cerebral ischemia in mice, and to observe its dose- and time-dependent properties. Permanent focal cerebral ischemia was induced by middle cerebral artery occlusion (MCAO). Montelukast was injected intraperitoneally either as multiple doses (once a day for 3 days and 30 min before MCAO) or as a single dose (at 30 min before, 30 min after, or 1 h after MCAO), respectively, and pranlukast and edaravone were used as controls. The neurological deficits, infarct volumes, brain edema, neuron density, and Evans blue extravasation in the brain were determined 24 h after MCAO. Pretreatments with multiple doses or a single dose of montelukast (0.1 and 1.0 mg/kg) before MCAO significantly attenuated all the ischemic insults. Post-treatment with a single dose of montelukast (0.1 and 1.0 mg/kg) at 30 min after MCAO also significantly decreased brain edema and infarct volume, but not neurological deficits. However, post-treatment with a single dose of montelukast at 1 h after MCAO had no significant effect. Pranlukast showed the same effects as montelukast, but edaravone attenuated the ischemic insults only with multiple doses before MCAO. Thus, montelukast has a dose- and time-dependent neuroprotective effect on permanent focal cerebral ischemia in mice, with an effective dose range of 0.1–1.0 mg/kg and a therapeutic window of 30 min. These findings further support the therapeutic potential of CysLT₁ receptor antagonists in the treatment of cerebral ischemia at earlier phases.

Salidroside (p-hydroxyphenethyl-beta-d-glucoside), which is present in all species of the genus Rhodiola, has been reported to have a broad spectrum of pharmacological properties. The present study, for the first time, focused on evaluating the effects of the purified salidroside on the proliferation of various human cancer cell lines derived from different tissues, and further investigating its possible molecular mechanisms. Cell viability assay and [(3)H] thymidine incorporation were used to evaluate the cytotoxic effects of salidroside on cancer cell lines, and flow cytometry analyzed the change of cell cycle distribution induced by salidroside. Western immunoblotting further studied the expression changes of cyclins (cyclin D1 and cyclin B1), cyclin-dependent kinases (CDK4 and Cdc2), and cyclin-dependent kinase inhibitors (p21(Cip1) and p27(Kip1)). The results showed that salidroside inhibited the growth of various human cancer cell lines in concentration- and time-dependent manners, and the sensitivity to salidroside was different in those cancer cell lines. Salidroside could cause G1-phase or G2-phase arrest in different cancer cell lines, meanwhile, salidroside resulted in a decrease of CDK4, cyclin D1, cyclin B1 and Cdc2, and upregulated the levels of p27(Kip1) and p21(Cip1). Taken together, salidroside could inhibit the growth of cancer cells by modulating CDK4-cyclin D1 pathway for G1-phase arrest and/or modulating the Cdc2-cyclin B1 pathway for G2-phase arrest.

Epidermolytic palmoplantar keratoderma (EPPK) is a relatively common autosomal-dominant skin disorder caused by mutations in the keratin 9 gene (KRT9), with few therapeutic options for the affected so far. Here, we report a knock-in transgenic mouse model that carried a small insertion–deletion (indel) mutant of Krt9, c.434delAinsGGCT (p.Tyr144delinsTrpLeu), corresponding to the human mutation KRT9/c.500delAinsGGCT (p.Tyr167delinsTrpLeu), which resulted in a human EPPK-like phenotype in the weight-stress areas of the fore- and hind-paws of both Krt9+/mut and Krt9mut/mut mice. The phenotype confirmed that EPPK is a dominant-negative condition, such that mice heterozygotic for the K9-mutant allele (Krt9+/mut) showed a clear EPPK-like phenotype. Then, we developed a mutant-specific short hairpin RNA (shRNA) therapy for EPPK mice. Mutant-specific shRNAs were systematically identified in vitro using a luciferase reporter gene assay and delivered into Krt9+/mut mice. shRNA-mediated knockdown of mutant protein resulted in almost normal morphology and functions of the skin, whereas the same shRNA had a negligible effect in wild-type K9 mice. Our results suggest that EPPK can be treated by gene therapy, and this has significant implications for future clinical application.

1. The aim of the present study was to investigate the mechanism underlying biochanin A-induced relaxation of the aorta in spontaneously hypertensive rats (SHR). 2. The tension in isolated ring preparations of thoracic aortas from normotensive (Wistar-Kyoto (WKY) rats) and SHR at 5 and 10 weeks of age was measured isometrically. 3. Biochanin A (10(-7) to 10(-4) mol/L) induced a concentration-dependent relaxation in aortic rings from both strains at the age of 5 and 10 weeks and the relaxation was greater in rings from 10-week-old SHR compared with age-matched WKY rats. The vasorelaxation induced by biochanin A was significantly reduced by denudation of the endothelium in aortic rings from SHR, but not WKY rats. Treatment with either indomethacin, a cyclo-oxygenase inhibitor, or N(omega)-nitro-L-arginine methyl ester, a nitric oxide synthase inhibitor, had little effect on the relaxation induced by biochanin A in aortic rings from either strain. Glibenclamide, a selective inhibitor of ATP-sensitive potassium channels, significantly attenuated the relaxation induced by biochanin A in aortic rings from both strains, although the extent of reduction was greater in WKY rats than SHR. Conversely, treatment with 4-aminopyridine, a selective inhibitor of voltage-dependent potassium channels, or tetraethylammonium, an inhibitor of calcium-activated potassium channels, significantly reduced the vasorelaxation induced by biochanin A in rings from SHR but not WKY rats. 4. The greater vasorelaxation produced by biochanin A in aortic rings from 10-week-old SHR is endothelium dependent. Different mechanisms underlie the relaxant effects of biochanin A in aorta from SHR and WKY rats. The mechanisms of biochanin A-induced vasorelaxation in thoracic aortas from both normotensive and hypertensive rats involve ATP-sensitive potassium channels and, in addition, in rings from the hypertensive strain at 10 weeks of age, an endothelium-derived activation of smooth muscle cell potassium channels contributes to the vasorelaxation observed.

Background Basic medical laboratory courses (BMLCs) play an essential role in medical education and offer several benefits to students. Although various student-centered and active learning strategies have been increasingly incorporated into medical education, their applications in BMLCs are limited. This paper aimed to explore the educational effects of a flipped classroom (FC) combined with team-based learning (TBL) strategy in BMLCs at Zhejiang University School of Medicine. Methods Four hundred eight 3rd-Year medical students were assigned to either the FC-TBL group (n = 235) or the FC group (n = 173) to complete three experiments on the respiration block of BMLCs. The two groups’ immediate and long-term academic performance were compared, and the FC-TBL students’ perceptions of different instructional strategies were surveyed. Results Students in the FC-TBL group scored higher on the immediate post-tests after class and higher on the final exams in two of the three experiment sessions. They preferred FC-TBL to FC for its higher engagement, more feedback, and better learning environment. Students felt the FC with TBL blended instructional strategy stimulated their interest in learning and deep thinking. Conclusions Compared with the FC group, students in the FC-TBL group improved academic performance and had a more positive experience overall. Our findings support the feasibility and advantage of the flipped classroom with team-based learning as a blended learning strategy in the BMLC curriculum.