利用噬菌体肽库序贯筛选组织因子靶向肽

目的: 建立一种高效的筛选跨膜受体靶向肽的噬菌体展示新方法,据此筛选出组织因子( TF) 高亲和力靶向肽。方法: 分别以纯化TF蛋白和具有TF高特异性表达的结直肠癌细胞株HT-29为靶标,用噬菌体七肽库进行序贯筛选(受体-细胞序贯筛选法,STRCA法),ELISA初步鉴定噬菌体克隆对HT-29亲和力。对噬菌体克隆进行测序,利用竞争抑制 ELISA比较各合成肽的TF结合力。重复实验检测筛选结果的可靠性。结果: 经过5轮筛选,与TF结合的噬菌体得到了富集,回收率由(2.25×10^-4)%增加到(1.32×10^-2)%;ELISA结果显示30个克隆中,阳性率为76.7%。噬菌体测序结果中,4种合成肽(分别命名为A、B、C、D肽)中A肽序列重复率为23.3%(7/30),B肽为23.3%(7/30),C肽为26.7%(8/30),D肽为10.0%(3/30);E肽为A、B肽合成的复合靶向肽。经竞争抑制 ELISA比较5种肽的TF亲和力,其IC₅₀分别为3.25 nmol/L、6.72 mol/L、3.24×10³ mol/L、2.08×10² mol/L和45.77 mol/L。重复实验所获得的阳性噬菌体克隆序列与第1次实验相比,重复率为33.3%。结论: STRCA法是一种理想的筛选跨膜受体靶向肽方法,采用该法获得的TF靶向肽对TF具有高度的亲和力。     

以一般性人际关系维度构建家庭关系功能量表

目的:改编适合中国文化背景的家庭关系功能量表。方法:以Shek等人编制的家庭功能量表为基础,结合访谈结果确定量表项目。采用探索性因素分析构建量表的一般性人际关系三因子维度,用验证性因素分析检验量表的效度并进行信度分析。结果:最终形成30个项目的家庭关系功能量表;EFA结果得到3个因子:情感性、控制性和行动力;CFA表明三因子模型在不同评价者和不同家庭关系上拟合良好;同质信度为0.81-0.93,分半信度为0.80-0.94。结论:改编的家庭关系功能量表具有良好的信效度符合心理测量学基本要求。     

钛植入物促骨整合及抗感染涂层的研究进展

钛及其合金具有稳定的化学性质和良好的人体亲和性,常被作为骨科植入材料,但未经处理的钛植入物易发生骨整合不良和植入物周围感染导致植入失败。近年来,人口老龄化加剧带动植入材料使用量增加,亟需性能更好的钛表面修饰方法以降低植入失败率。理想的骨科植入物应同时具备促成骨和抗菌特性,但目前大量表面改性策略只解决其中一种问题,导致植入物无法达到预期效果。因此,植入材料涂层需满足这两种特性或在两者间寻找平衡点。综述近几年来解决钛植入物无菌性松动或感染问题的最新策略,如表面形貌改善和生物分子涂层等促进成骨,抗菌药物负载和光热治疗等防治感染措施,并通过双因素整合和三因素整合进一步介绍了同时解决这两个问题的研究进展。     

胸主动脉腔内修复术中应用体外开窗技术重建左锁骨下动脉的临床分析

目的 探讨体外开窗技术在胸主动脉腔内修复术(TEVAR)中重建左锁骨下动脉(LSA)的方法和疗效。方法 回顾性分析2016年1月—2018年12月南京鼓楼医院和徐州市中心医院血管外科应用体外开窗技术在TEVAR中重建LSA的67例患者的临床资料,其中男51例、女16例,年龄41～76(63±5)岁。67例中,B型主动脉夹层50例、胸主动脉瘤11例、壁间血肿4例、主动脉溃疡2例。观察患者TEVAR后的内漏发生率,主体和分支支架的位置、完整性和通畅性,以及患者手术相关死亡率。结果 67例患者中,有66例成功采用体外开窗技术重建LSA,技术成功率达98.5%;另1例因术中对位不准确转为烟囱技术重建LSA,术后均获随访(3~48个月)。术后即刻造影提示存在少量Ⅰ型内漏3例,未予处理,术后3个月复查主动脉CT血管造影(CTA))提示内漏消失;2例患者术后出现左上肢乏力,其中1例伴头晕,均在随访过程中逐渐恢复,无肢体缺血坏死。随访中所有患者分支支架及主体支架均通畅并保持着良好的完整性,无主动脉覆膜支架移位、内漏等并发症,无手术相关死亡患者。结论 体外开窗技术为TEVAR中重建LSA提供了技术支持,方法简单有效,短、中期随访结果满意。     

33911例新生儿听力联合耳聋基因筛查及随访结果的分析

目的通过分析新生儿听力联合耳聋基因筛查的结果,以及对阳性病例的随访和管理,提高遗传性耳聋的检出率。方法收集33911例新生儿听力联合耳聋基因筛查的结果,应用Sanger测序对听力未通过或基因筛查提示阳性的患儿进行验证。结果听力初筛通过率为93.32%,复筛为87.01%。耳聋基因筛查阳性率为4.18%。GJB2、SLC26A4、GJB3和12SrRNA基因变异的检出率分别为1.98%、1.58%、0.37%和0.25%。共检出126例迟发性耳聋,84例药物性耳聋,4例GJB2纯合/复合杂合变异,5例SLC26A4纯合/复合杂合变异。联合筛查发现GJB2、SLC26A4、GJB3和12SrRNA单杂合变异者听力初筛和复筛未通过的比例分别为6.75%和2.61%、3.3%和1.2%、0.72%和0.14%、0.36%和0%。纯合/单基因复合杂合变异、单基因杂合变异、多基因复合杂合以及GJB3纯合变异组听力筛查未通过率明显高于阴性组,差异具有统计学意义。结论基因检测是对新生儿听力筛查很好的补充。对阳性患儿的追踪管理能够有效提高耳聋的诊断率,但基因筛查不能等同于诊断,应综合分析基因检测、听力筛查和影像学的结果,Sanger/二代测序可作为重要的补充检查手段。     

新冠肺炎患者焦虑症状及相关因素

目的:调查新冠肺炎患者的焦虑症状并分析相关因素。方法:新冠肺炎患者108例,采用自编一般资料调查表、广泛性焦虑量表(GAD-7)、简易应对方式量表(SCSQ)进行调查。结果:GAD-7总分(10.3±4.5)分。对GAD-7各条目进行秩和检验发现,有焦虑症状患者的GAD-7得分大于无焦虑症状患者(P<0.05)。GAD-7总分与积极应对得分呈负相关(r=-0.44,P<0.001),与消极应对得分呈正相.关(r=0.31,P<0.01)。二分类logistic回归分析显示,有发热症状、有接触史是焦虑症状的危险因素(OR=33.40、18.13),男性、积极应对是焦虑症状的保护因素(OR=0.02、0.03)。结论:新冠肺炎患者为女性、出现发热、有接触史时其焦虑症状越严重。     

Serum Antibodies to N-Glycolylneuraminic Acid Are Elevated in Duchenne Muscular Dystrophy and Correlate with Increased Disease Pathology in Cmah−/−mdx Mice

Humans cannot synthesize the common mammalian sialic acid N-glycolylneuraminic acid (Neu5Gc) because of an inactivating deletion in the cytidine-5''-monophospho-(CMP)–N-acetylneuraminic acid hydroxylase (CMAH) gene responsible for its synthesis. Human Neu5Gc deficiency can lead to development of anti-Neu5Gc serum antibodies, the levels of which can be affected by Neu5Gc-containing diets and by disease. Metabolic incorporation of dietary Neu5Gc into human tissues in the face of circulating antibodies against Neu5Gc-bearing glycans is thought to exacerbate inflammation-driven diseases like cancer and atherosclerosis. Probing of sera with sialoglycan arrays indicated that patients with Duchenne muscular dystrophy (DMD) had a threefold increase in overall anti-Neu5Gc antibody titer compared with age-matched controls. These antibodies recognized a broad spectrum of Neu5Gc-containing glycans. Human-like inactivation of the Cmah gene in mice is known to modulate severity in a variety of mouse models of human disease, including the X chromosome–linked muscular dystrophy (mdx) model for DMD. Cmah^−/−mdx mice can be induced to develop anti–Neu5Gc-glycan antibodies as humans do. The presence of anti-Neu5Gc antibodies, in concert with induced Neu5Gc expression, correlated with increased severity of disease pathology in Cmah^−/−mdx mice, including increased muscle fibrosis, expression of inflammatory markers in the heart, and decreased survival. These studies suggest that patients with DMD who harbor anti-Neu5Gc serum antibodies might exacerbate disease severity when they ingest Neu5Gc-rich foods, like red meats.

Sialic acids (Sias) are negatively charged monosaccharides commonly found on the outer ends of glycan chains on glycoproteins and glycolipids in mammalian cells.¹ Although Sias are necessary for mammalian embryonic development,^1,2 they also have much structural diversity, with N-acetylneuraminic acid (Neu5Ac) and N-glycolylneuraminic acid (Neu5Gc) comprising the two most abundant Sia forms in most mammalian tissues. Neu5Gc differs from Neu5Ac by having an additional oxygen at the 5-N-acyl position.³ Neu5Gc synthesis requires the cytidine-5''-monophospho (CMP)-Neu5Ac hydroxylase gene, or CMAH, which encodes a hydroxylase that converts CMP-Neu5Ac to CMP-Neu5Gc.^4,5 CMP-Neu5Ac and CMP-Neu5Gc can be utilized by the >20 sialyltransferases to attach Neu5Ac or Neu5Gc, respectively, onto glycoproteins and glycolipids.^1,3Humans cannot synthesize Neu5Gc, because of an inactivating deletion in the human CMAH gene that occurred approximately 2 to 3 million years ago.⁶ This event fundamentally changed the biochemical nature of all human cell membranes, eliminating millions of oxygen atoms on Sias on the glycocalyx of almost every cell type in the body, which instead present as an excess of Neu5Ac. Consistent with the proposed timing of this mutation at around the emergence of the Homo lineage, mice with a human-like inactivation of CMAH have an enhanced ability for sustained aerobic exercise,⁷ which may have provided an evolutionary advantage. In this regard, it is also interesting that the mild phenotype of X chromosome–linked muscular dystrophy (mdx) mice with a dystrophin mutation that causes Duchenne muscular dystrophy (DMD) in humans is exacerbated and becomes more human-like on mating into a human-like CMAH null state.⁸Inactivation of CMAH in humans also fundamentally changed the immunologic profile of humans. Almost all humans consume Neu5Gc from dietary sources (particularly the red meats beef, pork, and lamb), which can be taken up by cells through a salvage pathway, sometimes allowing for Neu5Gc expression on human cell surfaces.9, 10, 11, 12, 13 Meanwhile, most humans have some level of anti–Neu5Gc-glycan antibodies, defining Neu5Gc-bearing glycans as xeno-autoantigens recognized by the immune system.13, 14, 15, 16 Humans develop antibodies to Neu5Gc not long after weaning, likely triggered by Neu5Gc incorporation into lipo-oligosaccharides of commensal bacteria in the human upper airways.¹³ The combination of xeno-autoantigens and such xeno-autoantibodies generates xenosialitis, a process that has been shown to accelerate progression of cancer and atherosclerosis in mice with a human-like CMAH deletion in the mouse Cmah gene.^17,18 Inactivation of mouse Cmah also leads to priming of macrophages and monocytes¹⁹ and enhanced reactivity²⁰ that can hyperactivate immune responses. Cmah deletion in mice also causes hearing loss via increased oxidative stress,^21,22 diabetes in obese mice,²³ relative infertility,²⁴ delayed wound healing,²¹ mitochondrial dysfunction,²² changed metabolic state,²⁵ and decreased muscle fatigability.⁷Given that Cmah deletion can hyperactivate cellular immune responses, it is perhaps not surprising that the crossing of Cmah deletion in mouse models of various human diseases, to humanize their sialic acid repertoire, can alter pathogenic disease states and disease outcomes. This is true of cancer burden from transplantation of cancer cells into mice,¹⁷ infectious burden of induced bacterial infections in mice,^13,18,19 and muscle disease burden in response to Cmah deletion in the mdx model of Duchenne muscular dystrophy⁸ and the α sarcoglycan (Sgca) deletion model of limb girdle muscular dystrophy 2D.²⁶ The mdx mice possess a mutation in the dystrophin (Dmd) gene that prevents dystrophin protein expression in almost all muscle cells,²⁷ making it a good genetic model for DMD, which also arises from lack of dystrophin protein expression.^28,29 These mdx mice, however, do not display the severe onset of muscle weakness and overall disease severity found in children with DMD, suggesting that additional genetic modifiers are at play to lessen mouse disease severity, some of which have been described.30, 31, 32, 33, 34, 35, 36 Cmah deletion worsens muscle inflammation, in particular recruitment of macrophages to muscle with concomitant increases in cytokines known to recruit them, increases complement deposition, increases muscle wasting, and premature death in a fraction of affected mdx mice.⁸ Cmah-deficient mdx mice have changed cardiac function.³⁷ Prior studies⁸ show that about half of all mice display induced antibodies to Neu5Gc, which correlates well with the number of animals showing premature death in the 6- to 12-month period. Unpublished subsequent studies suggest that Cmah^−/−mdx mice that lack xeno-autoimmunity often have less severe disease, which likely causes selection for more efficient breeders lacking Neu5Gc immunity over time. Current studies were designed to re-introduce Neu5Gc xeno-autoimmunity into serum-naive Cmah^−/−mdx mice and describe the impact of xenosialitis on disease pathogenesis.     

正常生活状态下的大鼠脑中 FOS的基础表达

用免疫组织化学 ABC方法普查了正常生活状态下大鼠全脑内 FOS的基础表达。结果显示在正常生活状态下大鼠脑中有广泛而恒定的 FOS表达 ,出现于许多核团 ,如 :孤束核的连合核、内侧亚核 ,脑桥核 ,臂旁外侧核及 KF核 ,下丘 ,丘脑室旁核 ,下丘脑乳头体上核、视交叉上核以及中央杏仁核 ,新皮质等处。另外 ,在外侧网状核 ,三叉神经脊束核尾侧亚核 ,A1区 ,舌下神经前置核 ,小脑皮质颗粒层 ,中央灰质腹外侧部 ,腹侧被盖区 ,顶盖前区 ,下丘脑后区 ,外侧膝状体腹侧核 ,外侧缰核 ,尾壳核 ,屏状核 ,视上核 ,隔外侧核 ,扣带回皮质和嗅结节等处也有恒定的 FOS表达。面部皮下注射甲醛后 ,在部分脑区如三叉神经脊束核尾侧亚核 、 层及下丘脑室旁核等处 FOS表达增多 ,而脑内大部分核团 FOS表达模式未变。本文作者推测 ,这些正常生活状态下的 FOS表达可能与机体的基础代谢以及内脏、躯体功能活动 ,外界刺激如光线、声音等感觉传入活动有关。在分析实验刺激引起的 F OS表达变化时应注意区分     

妊高征不同孕期、不同程度的血液流变性观察

目的 :为探明妊高征血液流变性的变化规律。方法 :对12 5例妊高征患者的 13项血流变参数进行检测。结果 :(1)妊高征晚期与中期妊娠比较 ,纤维蛋白原、体外血栓长度、湿重、干重、血小板粘附率明显升高 (P <0 .0 5 ) ;(2 )重度妊高征较轻度妊高征血球压积明显降低 ,而血小板粘附率明显升高 (P <0 .0 5 ) ;(3)治疗后血球压积和血沉方程K明显下降 (P <0 .0 5 )。结论 :妊高征患者血液流变学部分指标发生改变 ,与不同孕期、不同程度及是否治疗密切相关。