Bufalin,a bufanolide steroid from the parotoid glands of the Chinese toad,suppresses hERG K+ currents expressed in HEK293 cells

In this study, we investigated the effect of bufalin on the human ether‐à‐go‐go‐related gene (hERG) K⁺ channels using the perforated patch recording technique. We measured a half‐maximal inhibitory concentration (IC₅₀) of 24.83 μM and maximal inhibitory effect of 39.45 ± 1.14% with bufalin. These findings suggest that bufalin is a potent hERG K⁺ channel blocker and may provide a new way for understanding Chan Su‐induced arrhythmia.     

日光温室作业对蔬菜种植人员眼健康的影响

目的探讨日光温室作业对蔬菜种植人员眼健康的影响。方法选取西北某地区739名温室蔬菜种植人员(温室组)和263名非温室蔬菜种植人员(非温室组)作为研究对象,采用问卷调查方式收集其一般人口学信息和眼异常症状情况,并测量双侧裸眼视力。结果温室组和非温室组人员左眼视力分别为4.89±0.33和4.91±0.25,差异无统计学意义(P>0.05);右眼视力分别为4.86±0.32和4.91±0.24,差异具有统计学意义(P<0.05)。男性温室组右眼视力(4.89±0.38)低于非温室组(4.98±0.22),差异具有统计学意义(P<0.05);女性温室组与非温室组右眼视力分别为4.84±0.28和4.89±0.24,差异无统计学意义(P>0.05)。温室组和非温室组眼痒、眼干等眼部异常症状发生率差异均无统计学意义(P>0.05)。多因素分析显示,年龄、性别和眼异常症状种类数是影响视力的重要因素(P<0.05);女性和温室作业人员更易出现眼异常症状(P<0.05)。结论日光温室作业可能引起蔬菜种植人员眼损伤风险升高,主视眼视力可能更易受损。     

缺氧条件下白花丹醌对肝癌HepG2细胞增殖、凋亡与侵袭及HIF-1α表达的影响

目的 研究白花丹醌在缺氧条件下对人肝癌细胞HepG2增殖、凋亡、侵袭和低氧诱导因子1α(hypoxia induced factor1α，HIF-1α)及其下游基因表达的影响。方法 采用二氯化钴(CoCl₂)化学诱导法建立HepG2细胞体外缺氧模型，经不同浓度(2，4，8 μmol·L^–1)白花丹醌处理24 h后，MTT、平板克隆形成试验观察HepG2细胞增殖水平变化；使用Annexin V/PI双染流式细胞术检测HepG2细胞凋亡情况；使用Transwell试验观察HepG2细胞侵袭能力的变化；使用qRT-PCR检测HepG2细胞内HIF-1A mRNA转录水平变化；使用Western blotting检测细胞内HIF-1α及其下游基因c-Myc、VEGFA、MMP9和TWIST1的蛋白表达水平。结果 当CoCl₂处理浓度为150 μmol·L^–1时，HepG2细胞增殖水平未见显著变化，而HIF-1α蛋白表达水平显著升高(P<0.01)，提示体外缺氧模型建立成功。与常氧对照组相比，MTT、平板克隆形成试验结果显示不同浓度白花丹醌作用HepG2细胞后，其增殖水平受到显著抑制(P<0.05或P<0.01)； Transwell试验结果显示白花丹醌可显著抑制HepG2细胞侵袭(P<0.05或P<0.01)；流式细胞术结果表明白花丹醌能显著诱导HepG2细胞凋亡(P<0.05或P<0.01)；Western blotting及qRT-PCR检测结果显示，白花丹醌能显著下调HIF-1α蛋白及HIF-1A mRNA表达水平(P<0.05或P<0.01)。Western blotting检测结果显示HIF-1α及其下游基因c-Myc、VEGFA、MMP9和TWIST1的蛋白表达水平均显著下调(P<0.05或P<0.01)。结论 CoCl₂体外模拟肝癌HepG2细胞缺氧的适宜浓度为150 μmol·L^–1；在缺氧条件下，白花丹醌可显著抑制肝癌HepG2细胞的增殖与侵袭，同时诱导细胞凋亡，其作用机制可能与下调HIF-1α蛋白及其下游靶基因蛋白表达有关。     

Substitutions of strontium in mesoporous calcium silicate and their physicochemical and biological properties

Calcium silicate (Ca–Si) based bioceramics have been regarded as a potential bioactive materials for bone tissue regeneration. In this study, we have successfully prepared ordered mesoporous strontium (Sr)-substituted CaSiO₃ (Sr–CaSiO₃) materials by using a triblock copolymer (P123) as a structure-directing agent. The microstructure and porosity of mesoporous Sr–CaSiO₃ materials were investigated by X-ray diffraction, scanning electron microscopy, transmission electron microscopy and the N₂ adsorption–desorption technique. The substitution of Sr for Ca in mesoporous CaSiO₃ did not change the mesoporous structure, but the surface area and pore volume decreased with increasing Sr substitution. The effects of the Sr substitution on the physiochemical and biological properties of mesoporous CaSiO₃ materials were evaluated by the ion dissolution, apatite-forming ability, proliferation and alkaline phosphatase (ALP) activity of osteoblast-like MC3T3-E1 cells. The results showed that the increasing Sr substitution decreased the dissolution rate of Ca and Si ions from mesoporous CaSiO₃ materials and enhanced the ability to stabilize the pH environment. Mesoporous Sr–CaSiO₃ materials have a similar apatite-forming ability to mesoporous CaSiO₃ material, and stimulated the proliferation and ALP activity of MC3T3-E1 cells. Furthermore, using gentamicin as a model drug, mesoporous Sr–CaSiO₃ materials exhibited a sustained drug release property which could be used in local drug delivery therapy. Furthermore, the drug release rate decreased to some extent with increasing Sr substitution in mesoporous CaSiO₃ materials. Therefore, mesoporous Sr–CaSiO₃ materials have more potential for application in bone tissue regeneration.     

积极稳妥地开展颈动脉内膜切除术，预防缺血性脑血管病

一次偶然的机会去参观一座城市中心医院的神经内科病房，科主任兴致勃勃地讲述新建病房的规模扩大为4个病区，床位是10年前的4倍，仔细看后发现住院患者绝大多数是缺血性脑血管病患者。在为当地医疗条件的改善感到欣慰的同时，我意识到，这个城市的人口10年间增长不到两成，而缺血性脑血管病却大幅度增长。而增长的原因除患者住院就医意识增强外，脑血管病患者似乎更多了!换言之，脑血管病的预防没有相应跟上，才是脑血管病患者增多的真正原因!     

红景天苷对HepG2细胞增殖、迁移、侵袭及凋亡的影响

目的 红景天苷是从红景天的根茎部中提取得到的，是红景天中含量最高的天然活性化合物。该实验旨在研究红景天苷对人源性肝癌细胞（HepG2细胞）增殖、迁移、侵袭和凋亡的影响。方法 选取未作任何处理的HepG2细胞作为空白组，以终浓度为20、40、80 μmol·L^-1红景天苷处理的HepG2细胞作为红景天苷组。采用多功能细胞分析仪测定红景天苷对HepG2细胞增殖的影响，划痕实验测定红景天苷对HepG2细胞迁移能力的影响，Transwell小室实验测定红景天苷对HepG2细胞侵袭能力的影响，倒置显微镜观察红景天苷对HepG2细胞形态的影响，透射电镜观察红景天苷对HepG2细胞中线粒体的影响，流式细胞术分析红景天苷对HepG2细胞凋亡及周期分布的影响，实时荧光定量聚合酶链式反应（Real-time PCR）测定红景天苷对HepG2细胞相关凋亡基因的影响，蛋白免疫印迹法测定红景天苷对HepG2细胞相关迁移、侵袭及凋亡蛋白的影响。结果 与空白组比较，红景天苷组（20、40、80 μmol·L^-1）细胞指数均明显下降（P<0.05），愈合面积均明显增加（P<0.05），且呈时间和浓度依赖性；红景天苷组（20、80 μmol·L^-1）中能够穿过Matrigel基质胶的HepG2细胞数量呈浓度依赖性减少；红景天苷组（20、40、80 μmol·L^-1）总凋亡率呈浓度依赖性升高，且阻滞细胞于G₂/M期（P<0.05）；红景天苷组（20、80 μmol·L^-1）上皮性钙黏附蛋白（E-cadherin）表达呈浓度依赖性升高（P<0.05），神经钙黏附蛋白（N-cadherin）表达呈浓度依赖性降低（P<0.05）。红景天苷组（20、40、80 μmol·L^-1）胱天蛋白酶-3（Caspase-3）mRNA表达、B细胞淋巴瘤-2（Bcl-2）相关X蛋白（Bax）、Caspase-3蛋白及胱天蛋白酶-9（Caspase-9）蛋白表达均呈浓度依赖性升高（P<0.05），肌动蛋白结合蛋白（Girdin）及Bcl-2表达均呈浓度依赖性降低（P<0.05）。结论 红景天苷对HepG2细胞的增殖、迁移及侵袭均具有抑制作用，且通过线粒体途径诱导HepG2细胞凋亡。表明红景天苷可作为一种潜在的肝癌化疗候选药物。     

青少年热线咨询中反移情现象和影响因素

青少年是热线咨询的一个主要群体，热线咨询有其情境特殊性，会经常唤起咨询师的内在冲突，产生反移情现象，文章从热线的未知性、沉默的处理、青少年的特点、咨询师自身的特点等几个影响因素探讨了这一现象；最后，进行了总结并提出未来的展望。     

Association of heart rate and diabetes among 0.5 million adults in the China Kadoorie biobank: Results from observational and Mendelian randomization analyses

Background and aimsObservational studies have associated resting heart rate with incident diabetes. Whether the associations are causal remains unclear. We aimed to examine the shape and strength of the associations and assessed the causal relevance of such associations in Chinese adults.Methods and resultsThe China Kadoorie Biobank enrolled 512,891 adults in China. Cox proportional hazard regression models was conducted to estimate hazard ratios (HRs) for the associations of resting heart rate with type 2 diabetes and total diabetes. Among 92,724 participants, 36 single-nucleotide polymorphisms (SNPs) related to resting heart rate were used to construct genetic risk score. We used Mendelian randomization analyses to make the causal inferences. During a median follow-up of 9 years, 7872 incident type 2 diabetes and 13,349 incident total diabetes were documented. After regression dilution bias adjustment, each 10 bpm higher heart rate was associated with about a 26% higher risk of type 2 diabetes (HR, 1.26 [95% CI, 1.23, 1.29]) and 23% higher risk of total diabetes (HR, 1.23 [95% CI, 1.20, 1.26]). Instrumental variable analyses showed participants at top quintile compared with those at bottom quintile had 30% higher risk for type 2 diabetes (HR, 1.30 [95% CI, 1.17, 1.43]), and 10% higher risk for total diabetes (HR, 1.10 [95% CI, 1.02, 1.20]).ConclusionsThis study provides evidence that resting heart rate is an important risk factor for diabetes risk. The results suggest that novel treatment approaches targeting reduction of high heart rate for incidence of diabetes may be worth further investigation.     

Generalized multinucleate cell angiohistiocytoma with possible origin from fibroblasts: A clinicopathological study of 15 cases

Multinucleate cell angiohistiocytoma (MCAH) is a vascular and fibrohistiocytic proliferation with unknown pathogenesis. Clinical lesions tend to be localized to an anatomical area. Exceptionally, the generalized variant is rare. This study reports three cases of generalized MCAH, and analyzes the clinicopathological features of 15 cases reviewed in the published work. Compared with the localized variant, generalized MCAH affected both sexes equally, had an earlier age of onset and a predilection for the trunk and extremities. Histopathologically, the most characteristic feature is the giant, bizarre multinucleate cells with angulated cytoplasm. Systemic diseases or abnormal immune conditions were revealed in six patients with generalized MCAH. For the first time, we found that the present cases showed increased elastic fibers in the affected areas, suggesting that the synthetic function of fibroblasts was active. This study suggested that MCAH originates from fibroblasts and is a distinct entity with potential correlation with abnormal immune states.