鸡贫血病毒VP 3基因的克隆及其体外凋亡诱导效应的研究

用PCR方法扩增了鸡贫血病毒标准株的vp3基因,并将其克隆于真核表达载体pcDNA3上,构建了重组体pcDNA-vp3.经酶切鉴定及测序分析表明,该片段和预期相符.在体外利用LipofectAMINETM介导的基因转染,将pc-DNA-vp3、pcDNA3分别转入肝癌细胞系HepG2和二倍体肝细胞系L-02中,转染后的RT-PCR结果证实vp3基因在细胞中得到了表达.同时利用筛选稳定表达细胞株的技术和原位细胞凋亡检测法,证明了鸡贫血病毒是以凋亡的方式诱导细胞死亡,并且只诱导癌细胞的凋亡,而不诱导正常或二倍体细胞死亡.表明鸡贫血病毒vp3基因很可能成为一种极具潜力的抗肿瘤生物制剂.     

Experimental study on the antitumor effect of mouse B7-1 gene

ＴｗｏｓｉｇｎａｌｔｈｅｏｒｙｆｏｒＴｃｅｌａｃｔｉｖａｔｉｏｎｐｒｏｖｉｄｅｄａｎｅｗａｐｐｒｏａｃｈｆｏｒｔｕｍｏｒｇｅｎｅｔｈｅｒａｐｙ［１－２］．Ｅｘｐｒｅｓｓｉｏｎｏｆｃｏｓｔｉｍｕｌａｔｏｒｙｍｏｌｅｃｕｌｅｇｅｎｅｉｎｔｒａｎｓｆｅｃｔ...     

Hyperspectral interference tomography of nacre

Structural characterization of biologically formed materials is essential for understanding biological phenomena and their enviro-nment, and for generating new bio-inspired engineering concepts. For example, nacre—the inner lining of some mollusk shells—encodes local environmental conditions throughout its formation and has exceptional strength due to its nanoscale brick-and-mortar structure. This layered structure, comprising alternating transparent aragonite (CaCO₃) tablets and thinner organic polymer layers, also results in stunning interference colors. Existing methods of structural characterization of nacre rely on some form of cross-sectional analysis, such as scanning or transmission electron microscopy or polarization-dependent imaging contrast (PIC) mapping. However, these techniques are destructive and too time- and resource-intensive to analyze large sample areas. Here, we present an all-optical, rapid, and nondestructive imaging technique—hyperspectral interference tomography (HIT)—to spatially map the structural parameters of nacre and other disordered layered materials. We combined hyperspectral imaging with optical-interference modeling to infer the mean tablet thickness and its disorder in nacre across entire mollusk shells from red and rainbow abalone (Haliotis rufescens and Haliotis iris) at various stages of development. We observed that in red abalone, unexpectedly, nacre tablet thickness decreases with age of the mollusk, despite roughly similar appearance of nacre at all ages and positions in the shell. Our rapid, inexpensive, and nondestructive method can be readily applied to in-field studies.

Complex optical phenomena can emerge from a variety of biological or bio-inspired processes, from arrays of colors in peacocks (1) and other birds (2), butterflies (3), and opals (4), to the metal-like sheen of herring (5) and unique polarization-dependent properties of jewel beetles (6) and Pollia fruit (7). Nacre, or mother-of-pearl, is a prominent biologically formed mineral structure found throughout our oceans. It lines the inside of the shells formed by many mollusks, including bivalves, cephalopods, and gastropods. It features brilliant iridescent colors (Fig. 1) and is studied and emulated in part because of its outstanding mechanical performance (8, 9). The striking, colorful appearance of nacre has been a source of scientific curiosity since the days of Brewster (10), Rayleigh (11), and Raman (12, 13), and is the product of optical interference resulting from multiple interface reflections as light propagates through its stratified structure comprising stacks of transparent polygonal aragonite tablets (CaCO₃) interspersed with organic polymer (chitin and proteins) layers (14–16) (Fig. 1A). Nacre is one of seven mollusk shell structures (17). In the nacre structure, the aragonite tablets are typically 5 to 10 μm in diameter and hundreds of nanometers thick [200 to 1,100 nm across all shells, and 250 to 500 nm in red abalone (18)], while the organic sheets are an order of magnitude thinner (14, 16, 19). In columnar nacre formed by gastropods like abalone and snails (Fig. 1), co-oriented tablets are stacked on top of one another, while in sheet nacre formed by bivalves like pearl oysters and pen shells, co-oriented tablets are staggered diagonally (18) (see Movie S1 for an animation showing how co-oriented tablets are stacked in columnar nacre). Despite the significant structural and formation–mechanism differences, the thicknesses of tablets and organic layers are similar in columnar and sheet nacre, and so are the optical and mechanical behavior (20). The resulting palette of colors is primarily dependent on the nacre tablet thickness and the viewing angle, and the optical response that yields these colors can be understood as that of a Bragg reflector (21) with disorder in the layer thicknesses, where the optical band gaps are determined by the thicknesses of the transparent layers (5, 22, 23). Thus, the spectrum of light reflected from a nacre surface encodes information about its physical structure (Fig. 1 B–D).Open in a separate windowFig. 1.(A) Nacre, the colorful iridescent inner lining of some mollusk shells. Here, the red abalone, or H. rufescens, shell features columnar nacre, which comprises thousands of layers of polygonal aragonite tablets interspersed with organic sheets. (B) A close-up photograph of the nacre surface shows a variety of colors and nonuniformities. (C and D) Given a broadband white light source illuminating nacre at a fixed angle of incidence, variations in color are observed due to the difference in average thickness of aragonite tablets comprising nacre. (E) Hyperspectral interference tomography (HIT) setup: A hyperspectral camera collects predominantly specular reflectance data across a sample illuminated by a collimated source at a fixed angle of incidence from the normal to the sample (θ). The reflected light is polarized using a wire-grid polarizer. (F) A color photograph of a region of nacre that was analyzed. (G) Map of the mean tablet thickness (MTT) obtained using HIT, overlaid on a grayscale rendering of the photograph in F. Highlighted in red is a 5 × 5-mm region used to analyze the ontogeny of nacre in Fig. 4. The region around this area was masked off using opaque tape, which is highlighted with the dashed white box.Understanding and characterizing the structure of nacre and other biomaterials have deep and surprising implications. For example, the average thickness of the tablets comprising ancient nacre can be used as a proxy for local ocean temperatures at the time of nacre formation, enabling paleoclimatology spanning hundreds of millions of years (18, 24, 25). The structure of nacre is also an inspiration for engineered materials thousands of times stronger than the constituent materials (15, 26, 27). To that end, new techniques have been developed to probe and understand the structure of nacre, such as polarization-dependent imaging contrast (PIC) mapping using X-ray absorption near-edge structure spectroscopy combined with photoemission electron spectromicroscopy (18, 28, 29), or X-ray nanotomography (30). However, these characterization techniques such as cross-sectional electron microscopy result in the destruction of the sample and are time-consuming and costly.Here, we present a method for rapid, nondestructive, and large-scale structural characterization of disordered and nonuniform stratified thin-film materials and apply it to the analysis of nacre. Our all-optical method employs hyperspectral imaging combined with thin-film modeling to extract nacre mean tablet thicknesses (MTTs) and tablet degree of disorder (σ)—defined as the standard deviation of the thicknesses—across large areas (Fig. 1 E–G). This characterization method is designated as hyperspectral interference tomography (HIT). We used HIT to map the structure of mollusk shell nacre across many stages of development and identified a previously unexplored relationship between the age of the organism and the structure of the nacre layer. We investigated two particular species of nacre-forming mollusks, Haliotis rufescens (red abalone) and Haliotis iris (paua, or rainbow abalone; data only in SI Appendix), for which the aragonite tablet thicknesses lie within a range of 250 to 500 nm (18, 31); however, the method is applicable to any other transparent layered structure of animal, plant, geologic, or synthetic origin.     

胫骨延长柄在重度肥胖患者初次全膝关节置换术中的应用及疗效观察

目的：探讨胫骨延长柄在重度肥胖的终末期膝骨性关节炎患者初次全膝关节置换术（ TKA)中的应用及疗效。方法回顾性分析河南省人民医院骨科2009年5月—2012年5月在初次TKA中应用胫骨延长柄治疗的19例（23膝)终末期膝骨性关节炎患者的临床资料,其中男4例、女15例,年龄53~78岁,BMI （37．7±1．75) kg/m2。单侧置换15例（左侧9例、右侧6例),双侧置换4例。应用美国膝关节学会评分（ KSS)系统,记录患者手术前后KSS膝评分及膝功能评分,采用SPSS 17．0进行统计学分析,以评价临床疗效及假体生存率。结果17例（21膝)获得随访,平均随访44个月（27~65个月);2名患者失访。术后下肢力线良好,关节稳定,随访患者均无假体松动等相关并发症。17例患者末次随访时,21膝评分从术前的（20．8±4．5)分提高到（90．7 ± 3．4)分,膝功能评分从术前的（25．7 ± 4．8)分提高到（87．0 ± 3．7)分,差异均有统计学意义（P值均<0．01);经侧方应力试验,17例患者均未出现内翻和外翻类型的关节不稳;未出现假体周围骨折、感染、无菌性松动、髌骨骨折等并发症,假体生存率为100%。结论重度肥胖的终末期膝骨性关节炎患者接受初次TKA治疗时,应用胫骨延长柄可以分散应力,增强假体稳定性,降低术后并发症,可获得良好的临床疗效。     

输尿管镜碎石术后输尿管狭窄的治疗

目的研究输尿管镜碎石术后输尿管狭窄的治疗方法及效果。方法回顾性分析北京清华长庚医院2014年12月-2018年2月收治的输尿管镜碎石术后输尿管狭窄患者的临床资料。初次治疗、输尿管狭窄长度<2 cm的患者首选以内腔镜下治疗为主的手术方式(内腔镜下球囊扩张或球囊扩张+内切开)为内镜组,既往治疗失败或狭窄长度>2 cm的患者选择以尿路重建手术为主的治疗方式为腹腔镜/开放组,记录并观察患者术后发热、腰痛、留置输尿管支架管或肾造瘘管、超声、CT尿路造影、利尿肾图等情况。结果34例行内腔镜下治疗,11例行开放/腹腔镜尿路重建手术。内腔镜治疗病例中73.5%(25例)为初次治疗,尿路重建病例中63.6%(7例)术前有输尿管狭窄治疗史。内腔镜手术有效率44%,尿路重建术有效率76%,尿路重建术有效率为内腔镜治疗的1.73倍。结论虽然尿路重建手术有效率明显高于内腔镜下治疗,对于选择合适的病例,内腔镜手术仍可作为输尿管镜碎石术后输尿管狭窄的一线治疗。初次治疗可采用内腔镜治疗,有既往治疗史的患者则以尿路重建手术为主。     

内镜额部除皱术结合传统切开法除皱的效果

目的探讨内镜除皱术与传统除皱术相结合的治疗方式及效果。方法仅存在额部皱纹、眉间纹及眉下垂者采用内镜额部除皱术,切除或切断皱眉肌、降眉肌和额肌,必要时结合额部皮瓣上提悬吊技术即可;如同时存在中下面部皮肤老化、松弛下垂,则内镜额部除皱术尚需结合传统切开法的中面部或中下面部除皱术,做浅表肌腱膜系统（sMAs）筋膜的折叠或切除缝合,以及多余皮肤的切除剪裁。结果104例采用额部内镜除皱术,均取得良好的除皱和眉提升效果。并发症较少而轻微,包括表情肌去除部位的轻度凹陷、额部皮肤麻木、发际线轻微后移、皱纹去除不彻底等。无面神经颞支损伤等严重并发症发生。其中84例存在中下面部皮肤松弛下垂,在做内镜额部除皱的同时行耳前切口的传统除皱术,明显改善中下面部的皮肤老化,并使面部上下的年轻化协调一致。结论内镜额部除皱术设计合理、操作安全、效果明确,是一项切口小、损伤轻的微创技术,符合整形外科的发展趋势。对于同时存在有中下面部皮肤松弛者,如能结合传统切开法除皱术,面部年轻化的整体效果可进一步优化。     

微创单纯抽吸术与皮下组织剥离剪除术治疗腋臭的临床效果对比

目的 通过对腋毛区两种术式治疗腋臭的疗效对比,探索一种更好地治疗腋臭的手术方法.方法 对72例腋臭患者随机分为两组,36例行微切口单纯抽吸术（A组）,另36例经腋皱襞切开行皮下组织剥离剪除术（B组）,对两组的手术时间、疗效、并发症、瘢痕、恢复时间等进行总结对比分析.结果 经6～12个月随访,两组患者腋臭治疗总有效率100％.A组在手术时间、术后并发症、恢复时间、瘢痕、腋毛存活等方面明显优于B组,两组差异有统计学意义（P＜0.05）.结论 微创单纯抽吸术治疗腋臭疗效可靠,安全便捷,瘢痕更小而隐匿,并发症少,恢复快,更易被患者接受.     

不同椎板减压范围对BioFlex系统生物力学的影响

【摘要】 目的：利用有限元方法分析比较不同椎板减压范围对脊柱动态内固定BioFlex系统生物力学的影响。方法：利用Mimics 10.01三维重建软件建立正常L3～L5几何模型并利用ProE逆向工程软件建立BioFlex系统几何模型,按临床术式进行组装并导入ANSYS Workbench 14.0有限元分析软件进行前处理建立四种L3～L5三维有限元模型：完整状态L3～L5模型（INT组）,L4-L5椎板减压+1/2关节突切除+Bioflex模型（MF-BF组）,L4-L5椎板减压+全关节突切除+Bioflex模型（TF-BF组）,L4-L5椎板减压+髓核摘除+Bioflex模型（D-BF组）;在各模型L3椎体的上表面以及上关节突的关节面轴向予1200N载荷和8Nm、8Nm、6Nm、4Nm力矩下模拟人体腰椎正常生理轴向载荷、前屈、后伸、侧弯和扭转,L5椎体的下表面及下关节突表面各节点六个方向自由度完全固定。测量各模型固定节段和邻近节段的活动度以及邻近节段的髓核间应力与关节突应力,并进行分析比较。结果：椎板减压并置入动态内固定Bioflex系统后,脊柱固定节段的活动度各减压组较INT组明显减小（P＜0.05）,其中TF-BF组前屈活动度减小幅度最大达77.2%,MF-BF组后伸、侧弯、旋转活动度减小幅度最大分别达37.4%、67.2%、83.1%;邻近节段的活动度各减压组较INT组增大（P＜0.05）,其中MF-BF组前屈活动度增大幅度最大达22.9%,TF-BF组后伸、侧弯活动度增大幅度最大分别达18.2%、32.1%,DF-BF组旋转活动度增大幅度最大达13.8%。不同状态下固定节段及邻近节段活动度MF-BF组、TF-BF组及D-BF组间波动幅度不大,两两比较差异无统计学意义（P＞0.05）。邻近节段关节突应力及髓核间应力各减压组较INT组明显增大（P＜0.05）,其中TF-BF组关节突应力在后伸、旋转活动时增大幅度最大分别达81.6%、77.3%,DF-BF组关节突应力在侧弯活动时增大幅度最大达60.5%,DF-BF组髓核间应力在前屈活动时增大幅度最大达46.6%,MF-BF组髓核间应力在后伸、侧弯、旋转活动时增大幅度最大分别达11.8%、63.5%、51.3%;邻近节段的关节突应力与髓核间应力在不同状态下各减压组间波动幅度不大,两两比较差异无统计学意义（P＞0.05）。结论：置入BioFlex系统后脊柱固定节段的活动度明显减小,邻近节段的活动度增大,固定与邻近节段活动度不随椎板减压范围的改变而明显改变;邻近节段关节突应力及髓核间应力明显增大,其大小不随椎板减压节段范围的改变而明显改变。     

儿童重症监护病房收治意外伤害临床特征及死亡危险因素分析

目的:探讨儿童重症监护病房(PICU)收治意外伤害的临床特征和危险因素。方法:回顾性总结上海交通大学附属儿童医院2017年1月至2019年12月因意外伤害收住PICU的患儿。分存活组和死亡组,比较临床特点与实验室指标的差异,多因素Logistic回归筛选死亡的危险因素和受试者工作特征曲线确定其阈值。结果:(1)意外伤害...     

间充质干细胞对延缓大鼠放射性肺纤维化进展的作用研究

目的 评价人脂肪来源间充质干细胞对大鼠放射性肺纤维化进展的抑制作用。方法 选用雄性SD大鼠,共48只。采用随机数字表法从中选出36只大鼠,给予右侧全肺15 Gy X射线照射。造模结束后2 h,随机数字表法将受照大鼠分为3组:PBS对照组、成纤维细胞治疗组和干细胞治疗组,每组12只,剩余12只未受照大鼠作为健康对照组。于照射后第24周分别对受照右肺进行影像学及病理学检测。后者包括HE染色,Masson染色,免疫组织化学染色(α-SMA及TGF-β1)。分别获取受照大鼠的外周血及支气管-肺泡灌洗液样本,采用ELISA法检测样本中的肝细胞生长因子(HGF)和转化生长因子-β1(TGF-β1)的含量。采用实时荧光定量PCR法对受照肺组织内Ⅰ型胶原-α1(Collagen Ⅰ-α1)及 Ⅲ型胶原-α1(Collagen Ⅲ-α1)基因的表达量进行检测。结果 影像学检查结果显示,受照肺在造模后第24周出现高密度影,病变以右下叶最为明显。PBS对照组及成纤维细胞治疗组的大鼠右肺下叶受损程度较干细胞治疗组重。病理结果提示,PBS对照组及成纤维细胞治疗组的大鼠右肺下叶结构被破坏,表现为肺泡塌陷及肺泡间隔增宽。两组大鼠右肺下叶细胞外基质沉积明显;组织内Collagen Ⅰ-α1及Collagen Ⅲ-α1的表达量较干细胞治疗组提高(F=4.39、7.73, P<0.05)。PBS对照组及成纤维细胞治疗组的大鼠右肺下叶α-SMA及TGF-β1的表达明显。ELISA结果提示,干细胞治疗组的大鼠血清中及支气管-肺泡灌洗液中HGF的浓度显著高于其余两组(F=14.97、41.13, P<0.05);TGF-β1的浓度低于其余两组(F=172.49、62.82,P<0.05)。结论 人脂肪来源间充质干细胞能够抑制放射性肺纤维化的进展,对受照肺组织具有一定的保护作用。