Second-harmonic imaging of cornea after intrastromal femtosecond laser ablation

Nonlinear laser scanning microscopy is widely used for noninvasive imaging in cell biology and tissue physiology. However, multiphoton fluorescence imaging of dense, transparent connective tissue (e.g., cornea) is challenging since sophisticated labeling or slicing is necessary. High-resolution, high-contrast second harmonic generation (SHG) imaging of corneal tissue based on the intrinsic structure of collagen is discussed. The three-dimensional corneal ultrastructure in depths up to hundreds of microns can be probed noninvasively, without any staining or mechanical slicing. As an important application of second harmonic imaging in ophthalmology, the modification of corneal ultrastructure using femtosecond laser intrastromal ablation is systematically investigated to evaluate next-generation refractive surgical approaches.     

视网膜母细胞瘤基因对人骨肉瘤细胞株OS732的影响

目的 观察外源性N端截短的视网膜母细胞瘤（Rb)基因对骨肉瘤细胞株OS732的生长和细胞间缝隙连接信息通讯能力的影响。方法 构建N端截短的长度为1.65kb Rb基因的真核表达质粒,并用DOTAP将其导入骨肉瘤细胞株OS732。应用逆转录－聚合酶链反应（RT－PCR）和Northern blot检测Rb基因的表达;用细胞计数,流式细胞仪分析和软琼脂克隆形成试验观察OS732细胞的生成状况;用半定量RT－PCR法和罗氏黄荧光传输法检测细胞间缝隙连接信息通讯的能力。结果 转染N端截短的Rb基因后,OS732细胞内可检测到内源性和外源性Rb基因的mRNA表达。OS732细胞的形态发生改变,其生长速度减慢,软琼脂形成集落能力降低,细胞周期阻滞于G0－G1期;缝隙连接蛋白基因Gonnexin43的表达和细胞信息通讯能力增强。结论 N端截短的Rb基因可抑制骨肉瘤细胞株OS732的恶性生长表型以及增强细胞间信息通讯能力。     

Properties of utricular-activated vestibular neurons that project to the contralateral vestibular nuclei in the cat

The properties of utricular (UT)-activated vestibular neurons that send axons to the contralateral vestibular nuclei (commissural neurons) were investigated intracellularly or extracellularly in decerebrate cats. A total of 27 vestibular neurons were orthodromically activated by stimulation of UT nerves and antidromically activated by stimulation of the contralateral vestibular nuclei. All neurons tested were classified as vestibulospinal (VS), vestibulooculospinal (VOS), vestibuloocular (VO), and unidentified vestibular neurons (V) after antidromic stimulation of the spinal cord and oculomotor/trochlear nuclei. Most UT-activated commissural neurons (20/27) received monosynaptic inputs. Twelve of 27 commissural neurons were located in the medial vestibular nucleus, 5 were in the lateral vestibular nucleus, 10 were in the descending vestibular nucleus, and no commissural neurons were recorded in the superior vestibular nucleus. Seven of 27 neurons were commissural VS neurons, 9 of 27 were commissural VOS neurons, and 11 of 27 were commissural V neurons. No commissural VO neurons were found. All VOS neurons and 3 VS neurons issued descending axons via the medial vestibulospinal tract. We also studied convergent inputs from the posterior semicircular canal (PC) nerve onto UT-activated commissural neurons. Five of 27 UT-activated commissural neurons received converging inputs from the PC nerves. Electronic Publication     

肠道淋巴瘤与EB病毒相关性研究

目的：探讨EB病毒（Epstein-Barr virus,EBV)感染在肠道淋巴瘤发病中的意义。方法：采用EBV的DNA原位杂交及S－P法免疫组化技术（第一抗体为EBV、CD3、CD20、CD43、CD45、CD45RO、CD74等），观察24例肠道淋巴瘤患者（8例肠病相关T细胞淋巴瘤、16例黏膜相关淋巴组织B细胞淋巴瘤）EBV感染情况。以20例慢性结肠炎作为对照。结果：患者年龄21－92岁（平均52．8岁），男女之比为3．8：1。临床上均以腹痛、腹胀或便血就诊。组织病理学：T细胞淋巴瘤细胞多形性、核大，不规则，嗜血管性及大片坏死；B细胞淋巴瘤细胞中等大小，多呈圆形、椭圆形、胞质较少淡染，核稍大，核分裂象多见，可见“淋巴上皮病变”。24例淋巴瘤中检出（原位杂交及免疫组化）EBV－DNA 14例（检出率为58．3％），其中T细胞淋巴瘤EBV的检出率为75％，B细胞淋巴瘤EBV的检出率为50％（P＜0．01）。结论：肠道淋巴瘤的发生与EBV的感染有明显的相关性。     

Symptom Interval and Patient Delay Affect Survival Outcomes in Adolescent Cancer Patients

PurposeUnique features of adolescent cancer patients include cancer types, developmental stages, and psychosocial issues. In this study, we evaluated the relationship between diagnostic delay and survival to improve adolescent cancer care.ResultsMean SI was significantly longer in adolescents than in children (66.4 days vs. 28.4 days; p<0.001), and OS rates were higher in patients with longer SIs (p=0.001). In children with long SIs, OS did not differ according to PDP (p=0.753). In adolescents with long SIs, OS was worse when PDP was ≥0.6 (67.2%) than <0.6 (95.5%, p=0.007). In a multivariate analysis, adolescents in the long SI/PDP ≥0.6 group tended to have a higher hazard ratio (HR, 6.483; p=0.069) than those in the long SI/PDP <0.6 group (HR=1, reference).ConclusionAdolescents with a long SI/PDP ≥0.6 had lower survival rates than those with a short SI/all PDP or a long SI/PDP <0.6. They should be encouraged to seek prompt medical assistance by a physician or oncologist to lessen PDs.     

人羊膜匀浆上清液对大鼠角朊细胞生长的影响

目的观察不同浓度人羊膜匀浆上清液(hAHS)对体外培养的SD大鼠角朊细胞生长的影响。 方法取SD大鼠背部皮肤,采用中性蛋白酶与胰蛋白酶复合消化的方法,分离第一代角朊细胞。将新鲜人羊膜制备成hAHS,采用考马斯亮蓝法、酶联免疫吸附试验分别测定hAHS中总蛋白含量和表皮生长因子(EGF)、碱性成纤维生长因子(bFGF)、血管内皮生长因子(VEGF)的浓度。用不同浓度hAHS对第一代角朊细胞进行体外培养：将细胞以2.5×10⁴个/mL密度接种于96孔板中(每孔100 μL),随机数字表法将其分为体积分数0(对照组)及10%、15%、20%、25% hAHS组,用含10%胎牛血清低糖培养基培养24 h后,根据hAHS在低糖DMEM培养基中的不同体积分数进行换液,分别于培养即刻和培养24、48、96 h,用噻唑兰法检测各孔的吸光度值并绘制角朊细胞的生长曲线和计算各组细胞增殖率。采用SPSS13.0统计软件进行分析,各不同体积分数hAHS组的数据与对照组比较采用Dunnett－t检验。 结果hAHS中总蛋白含量为(675.435±9.215)×10^－3 g/L,EGF、bFGF和VEGF的浓度分别为(470.625±2.546)×10^－6、(4.121±0.026)×10^－6和(0.172±0.002)×10^－6 g/L。与对照组比较,10% hAHS组培养48、96 h角朊细胞增殖率明显高于对照组,差异均有显著性统计学意义(t＝4.644、9.694,P值均小于0.01),15% hAHS组培养48、96 h角朊细胞增殖率均明显高于对照组,差异均有显著性统计学意义(t＝4.766、6.648,P值均小于0.01);20% hAHS组培养24 h角朊细胞增殖率高于对照组,差异有统计学意义(t＝2.272,P<0.05),培养48、96 h增殖率均明显高于对照组,差异有显著性统计学意义(t＝5.027、8.861,P值均小于0.01);25% hAHS组培养48 h增殖率低于对照组,差异有统计学意义(t＝2.188,P<0.05),培养96 h增殖率明显低于对照组,差异有显著性统计学意义(t＝5.147,P<0.01)。 结论体积分数10%、15%、20% hAHS对体外培养的角朊细胞增殖有明显促进作用,且促增殖的效果随hAHS体积分数的增加而增强,但hAHS的体积分数在25%时角朊细胞的增殖受到抑制,平稳期相对缩短。     

镍钛形状记忆合金的生物相容性研究进展

镍钛形状记忆合金(Nickel titanium shape memory alloys,Ni Ti-SMA)因具有良好的生物相容性、形状记忆效应以及超弹性等优异性能成为理想的体内固定材料,目前已广泛的应用于临床治疗。由于镍钛形状记忆合金的形状记忆效应和超弹性可以有效避免应力遮蔽引起的材料断裂,因而有望长期存于人体内,但是合金在人体内受腐蚀释放的镍离子存在生物毒性,对局部组织有致敏甚至是致癌作用,所以又限制了其在临床上的广泛应用。本文综述了镍钛形状记忆合金生物相容性相关的文献,总结镍钛形状记忆合金在体外、动物体内生物相容性以及临床应用的生物相容性方面的研究进展,并指出镍钛形状记忆合金的表面处理在提高其生物相容性方面的重要性。     

机器人辅助椎弓根螺钉置钉的准确性观察

目的 评估机器人辅助行椎弓根螺钉置钉的准确性并观察置钉并发症。方法 回顾性分析2014年12月—2015年5月苏州大学附属第一医院骨科行机器人辅助椎弓根螺钉置入的13例患者临床资料。其中男6例,女7例;年龄41~73岁,平均56.5岁;L₁爆裂性骨折2例,L₂压缩性骨折1例,L₄滑脱症4例,T₁₂爆裂性骨折伴截瘫1例,L₁陈旧性压缩性骨折伴后凸畸形1例,退行性侧弯1例,先天性脊柱侧弯术后翻修1例,腰椎间盘突出症伴椎管狭窄症1例,脊髓灰质炎后遗症性脊柱侧弯1例。采用Gertzbein和Robbins标准,CT定量分析椎弓根螺钉位置,并记录置钉所致并发症如神经根、血管、脊髓损伤等。结果 由机器人辅助置钉成功12例,其中83枚螺钉由机器人成功辅助置入,1枚螺钉因术中机器人无法注册改为徒手置钉;另1例患者因术中发现机器人置钉的进针点偏差大,改为徒手置钉。根据Gertzbein和Robbins标准,A级80枚,B级2枚,C级1枚,置钉准确率达98.8%(82/83)。无置钉所致并发症如神经根、脊髓损伤及血管损伤等。结论 机器人辅助椎弓根螺钉置钉精准性高,可减少或避免置钉所致并发症。