医源性腓总神经伤分析

目的：总结40a来收治的48例医源性腓总神经损伤的临床资料，探讨其损伤机制和特点。方法：通过随访，依据其损伤原因和机制分类统计。结果：牵拉压迫伤33例，占69％；手术切割伤12例，占25％。导致腓总神经损伤的原因中以石膏压迫为最多，占37％，牵伸性损伤占31％。结论：骨科医师必须具备丰富的解剖知识和责任心，重在预防，一旦发生损伤，应早期诊断，采用有效的方法及时治疗。     

Increased mast cell density during the infection with velogenic Newcastle disease virus in chickens

In addition to their well-characterized role in allergic inflammation, recent data confirm that mast cells play a more extensive role in a variety of viral infections. The contribution of mast cells to Newcastle disease pathogenesis has not been investigated. We evaluated mast cell activity after Newcastle disease virus (NDV) infection in specific pathogen free chickens using cytochemical and immunocytochemical analyses. The results were as follows. Severe tissue damage was observed in the proventriculus, duodenum, jejunum and caecal tonsil, and NDV antigens were detected and presented extensively in these tissues. Second, in the NDV-infected group, the mast cell population was increased markedly in the proventriculus, duodenum, jejunum and caecal tonsil at 24, 48, 72 and 96 h after infection (P<0.01). However, very few mast cells were observed in those same tissues in the control. More intriguingly, the greatest number of mast cells was found in the proventriculus, which also showed the greatest level of NDV antigens. Third, the content of tryptase was significantly higher (P<0.01) in the NDV-infected group compared with the control from 24 to 96 h post infection). Furthermore, as an important protease released by mast cells, tryptase had a positive correlation with mast cell distribution. These data indicated that mast cells were involved in the response to NDV. Our results also suggested that the broad range of mast cell mediators might have a role in the pathology of Newcastle disease.     

“Smart” Materials for Biosensing Devices: Cell-Mimicking Supramolecular Assemblies and Colorimetric Detection of Pathogenic Agents

Mimicking cell membrane and the biomolecular recognition associated with membranes represents a great technical challenge, yet it has opened doors to innovative diagnostic and therapeutic methods. Our work has focused on design and synthesis of a class of smart materials exploiting biological principals for use in biosensors: these materials are functional polymeric assemblies that mimic the cell membrane and conveniently report the presence of pathogens with a color change. Biologically active cell membrane components are incorporated into conjugated polymers with desirable optical properties and the binding of the target molecules onto the material triggers conformational and electronic shifts that are reflected in a chromatic change (a so-called biochromic shift) that is conveniently observed and recorded. Langmuir–Blodgett thin films and vesicle bilayers provide ideal configurations for precise delivery of the biological binding entity to the sensing interface, and for control of molecular orientation for effective biomolecular interaction. Polydiacetylenic membrane-mimicking materials containing cell surface receptor gangliosides and sialic acid residues, respectively were formulated into these architectures and used for colorimetric detection of bacterial toxins and influenza virus. One advantage of these biochromic conjugated polymer (BCP) sensors is that their molecular recognition and signal transduction functionalities are resident in a single functional unit, making them amenable to convenient microfabrication and use.     

Natural polyreactive secretory immunoglobulin A autoantibodies as a possible barrier to infection in humans.

Secretory immunoglobulin A (S-IgA) was investigated in human secretions for the presence of natural antibodies (Abs) acting as the first "immune barrier" to infection before induction or boosting of specific responses. These molecules could be the secretory counterpart of the natural Abs in serum that were previously shown by our laboratory to be polyreactive to autoantigens. Significant levels of S-IgA Abs to human actin, myosin, tubulin, and spectrin were detected in 10 saliva and 8 colostrum samples from normal subjects. Computer-assisted analysis of immunoblots of extracts from human muscles showed these Abs to react with a large number of autoantigens. Their polyreactivity was confirmed by cross-inhibition and by immunoblotting studies of affinity-purified natural Abs, assayed against a large variety of surface or secreted antigens from Streptococcus pyogenes. The thiocyanate elution method showed that functional affinities of some natural Abs can be of the same order of magnitude as those of tetanus vaccine antitoxins. Moreover, nonimmune binding of these natural Abs to the gut protein Fv (Fv-fragment binding protein) can enhance their effector functions. This demonstrates that human secretions contain polyreactive auto-Abs which can also react with pathogens. These secretory Abs of "skeleton key" specificities are possibly produced by a primordial B-1-cell-associated immune system and can be involved in a plurispecific mucosal protection against pathogens, irrespective of the conventional immune response.     

杀虫剂点滴处理后德国小蠊的生理行为反应

本文报告了应用三种不同类型杀虫剂ＤＤＶＰ，残杀成和溴江菊酯点滴处理敏感株德国小蠊（Ｂｌａｔｔｅｌｌａｇｅｒｍａｎｉｃａ）不同虫期后的药物敏感性以及带荚虫脱荚及其孵化情况。试验得出了不同虫期不同时间的ＬＤ５０植和７２ｈ不同虫期对这３种药物敏感性的显著性测定（Ｐ值）的结果。发现不同虫期对这３种药物的敏感性之间关系的共同特点是：１．幼虫与雄虫敏感性差别显著（在ＤＤＶＰ和残杀威中）或者非常显著（在溴氰菊酯）；２．雌虫与雄虫间差别在３种药物处理中均显著；３．雌虫与带荚虫在ＤＤＶＰ和溴氰菊酯处理中差别也非常显著。试验同时显示，３种药物不同浓度处理对德国小蠊脱荚及其孵化有十分显著的影响。其总的趋势是随着药物浓度的增高脱荚率明显地增加；相反，脱荚的孵化率则随着浓度的增加明显的下降。实验并得出脱荚的孵化与否和卵荚长度无明显关系。     

胡萝卜籽挥发油的抗生育作用

胡萝卜籽挥发油对小鼠有抗着床,抗早、中和晚期妊娠作用。对大鼠也有抗着床作用。挥发油中的萜类碳氢化合物部位,对小鼠皮下注射抗早期妊娠的ED_(50)为2.9ml/kg,甲地孕酮和hCG能明显逆转其作用;对假孕小鼠蜕膜瘤有抑制作用,此作用不能被甲地孕酮拮抗,皮下注射于早孕大鼠24、48小时后血浆孕酮浓度明显下降。以上提示其抗早孕作用机制可能与抑制孕酮合成和蜕膜反应有关。此外,挥发油碳氢部分无雌激素和抗雌激素活性,低浓度时对早孕大鼠离体子宫的收缩活动没有影响,高浓度则表现抑制作用。     

526例50岁以上男性前列腺增生与血清睾酮含量的变化

目的揭示老龄人群前列腺增生的发病现状及血清睾酮水平的变化规律.方法以一汽集团50岁以上男性为研究对象,另设2组年龄对照,均行直肠指诊、经腹前列腺超声检查、放免技术测定血清睾酮与皮质醇含量.结果(1)50岁以上人群中BPH发现率,直肠指诊诊断率为60.05%,经腹超声诊断率为69.57%,并且随增龄明显增高;(2)血清睾酮含量随增龄下降,二者间呈明显的负相关关系(r=-0.45,P＜0.0001);(3)前列腺体积与血清睾酮含量呈显著的负相关关系(r=-0.224,P＜0.001).结论在50岁以上人群中BPH的发现率超过60%,并发现BPH的发病可能与血清睾酮含量下降有关.     

人脑星形细胞肿瘤中细胞凋亡及bcl-2，Bax基因的表达

目的 :探讨人脑星形细胞肿瘤组织中的细胞凋亡 ,以及细胞凋亡与其相关基因bcl 2、Bax表达之间的关系。方法 :采用原位末端标记的TUNEL技术及免疫组织化学S P法对 30例星形细胞肿瘤手术标本进行检测 ,分别观察了肿瘤组织中凋亡细胞密度及bcl 2、Bax基因的表达。结果 :星形细胞肿瘤组织中普遍存在细胞凋亡现象 ,凋亡细胞密度随肿瘤恶性度的升高 ,呈逐渐降低的趋势 (t=2 .77,P <0 .0 1) ;bcl 2、Bax在星形细胞肿瘤组织中表达阳性率分别为 5 0 %和 10 0 % ,其中bcl 2表达强度与凋亡细胞密度呈显著负相关 (r=- 0 .92 2 ,P <0 .0 0 1)。结论 :细胞凋亡受抑在星形细胞肿瘤发生及间变过程中起重要作用 ;bcl 2基因表达对细胞凋亡的发生起抑制作用 ;Bax基因对细胞凋亡的调节可能存在更为复杂的机制。     

METTL3-Mediated m6A mRNA Methylation Modulates Tooth Root Formation by Affecting NFIC Translation

N6-methyladenosine (m⁶A), as a eukaryotic mRNA modification catalyzed by methyltransferase METTL3, is involved in various processes of development or diseases via regulating RNA metabolism. However, the effect of METTL3-mediated m⁶A modification in tooth development has remained elusive. Here we show that METTL3 is prevalently expressed in odontoblasts, dental pulp cells, dental follicle cells, and epithelial cells in Hertwig's epithelial root sheath during tooth root formation. Depletion of METTL3 in human dental pulp cells (hDPCs) impairs proliferation, migration, and odontogenic differentiation. Furthermore, conditional knockout of Mettl3 in Osterix-expressing cells leads to short molar roots and thinner root dentin featured by decreased secretion of pre-dentin matrix and formation of the odontoblast process. Mechanistically, loss of METTL3 cripples the translational efficiency of the key root-forming regulator nuclear factor I-C (NFIC). The odontogenic capacity of METTL3-silenced hDPCs is partially rescued via overexpressing NFIC. Our findings suggest that m⁶A methyltransferase METTL3 is crucial for tooth root development, uncovering a novel epigenetic mechanism in tooth root formation. © 2020 American Society for Bone and Mineral Research (ASBMR).