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。     

急性脑卒中血清、尿、脑脊液β2—微球蛋白的临床研究

目的探讨急性脑卒中与血清、尿、脑脊液β2-MG的相关性及其临床意义.方法应用放射免疫法测定108例脑梗死和94例脑出血1周内β2-MG,并在1～3周后进行复查.同时测定部分尿β2-MG含量,部分做了脑脊液β2-MG含量动态观察.结果1周内血清、尿、脑脊液β2-MG含量(μg/L)脑梗死和脑出血组分别2417±1094和2004±1029、169.1±186.8和276.5±212.0、1994±1283和2983±1179,与正常对照组比较明显升高,P＜0.05或P＜0.001或P＜0.001.治疗1～3周后复查均有不同程度的减低.结论急性脑卒中与血、尿、脑脊液β2-MG有明显相关性,可用于观察病情变化.     

用腰椎X—线片半定量诊断骨质疏松的研究

目的验证JOA X-线骨质疏松诊断标准的可靠性.方法47名女性病人(年龄65.3±7.2岁)行腰椎常规X-线检查和第三腰椎正、侧位DEXA骨密度测量.用t检验验证X-线骨质疏松等级间骨密度的差异性,用Spearman相关性分析法检验X-线骨质疏松等级与骨密度值的相关性.结果X-线骨质疏松等级间骨密度具有显著性差异(P＜0.01),X-线骨质疏松等级与第三腰椎侧位骨密度值之间相关性最高(r=0.714).结论通过腰椎X-线片按照JOA标准划分骨质疏松等级,可以作为粗略检查腰椎骨质疏松的方法.     

自发性高血压大鼠左室不同部位心肌纤维化程度的改变: 病理变化与心肌密度改变的对比观察

目的：探讨自发性高血压大鼠（SHR）左室室间隔、前壁、后壁及侧壁 心肌纤维化的动态变化,以及心脏超声显像结合计算机分析检测心肌密度这一方法的可靠性。方法：应用病理及生化检查,检测SHR左室室间隔、间壁、后壁及侧壁心肌纤维化的病变程度;通过心脏超声显像并结合计算机分析,检测大鼠的心肌密度的变化。结果：14周时,代表心肌纤维化水平的参数羟脯氨酸浓度（HC）在SHR室间隔、前壁及后壁即已增高,以室间隔最为明显,而左室侧壁虽有增高趋势,但未达到显著性水平;24周时各部位均明显增加,但各部位之间的差异明显减少。在14周时,代表血管周围纤维化水平的参数血管周围胶原面积（PVCA）在左室各部位较对照组均显著增高,24周时增高更为明显,但各部位之间无显著性差异。而代表间质纤维化水平的参数胶原容积分数（CVF）在14周时只有室间隔显著增高,其余各部位无明显变化;24周时各部位均有显著增高,但仍以室间隔增高最为明显。心肌灰度均值在14周时各部位均较对照组显著增高,各部位之间比较,室间隔最高,侧壁最低,二者之间有显著性差别。24周时各部位均较14周显著增高,但各部位之间差别变小。在室间隔,灰度离散度在14及24周均未出现显著性改变,而其他部位则在14周时增高,24周时趋于正常。结论：在高血压发病过程中,心肌纤维化尤其是间质纤维化的变化程度是不均衡的,以室间隔程度最重,左室侧壁最轻;应用心脏超声显像并结合计算机分析测定心肌密度,可客观地反应心肌纤维化的程度。     

淋病奈瑟氏菌中国流行株gyrA和parC基因与喹诺酮类耐药性的相关性

目的　调查中国地区淋病奈瑟氏菌 (NG)对喹诺酮类的耐药性状况 ,探讨高水平耐药的基因突变株对喹诺酮类耐药机制的作用 .方法　对 9a来临床分离保存淋球菌流行株进行了体外环丙沙星 (CIP)药敏实验 .筛选出 76株高水平CIP耐药株 ,通过 PCR扩增了其中的 1 8株 NG的 gyr A和par C喹诺酮耐药决定区基因 ,并对扩增子直接测序 .通过N he I酶切、脉冲电场凝胶电泳 (PFEG)分析了这些菌株的遗传关系 .结果　环丙沙星的耐药检出率有逐年增高的趋势 ,MIC≥ 1 .0 mg· L- 1的菌株由 1 993年的 5 .1 %上升到 2 0 0 1年的 2 1 .4% .对照组中的 1 8株敏感菌只有两株发生了 gyr A的单一突变 ,未发现 par C变异 ;而耐药组中 89% (1 6 )菌株的gyr A发生了 Ser- 91向 Phe的单一突变株或 (和 ) par C的双突变 .88.9% (1 5 )的菌株的 gyr A发生了 Ser- 91向 Phe和 Asp-95向 Gly的突变 .在发生 par C突变中 72 %属于 Asp- 86向Asn突变 .PFEG分析发现 1 0株具有完全一致的 gyr A和par C突变模式 .同时也发现来自不同地区的菌株的 PFEG指纹图是不同的 .结论　研究表明 ,在中国 NG流行株对喹诺酮类耐药率呈增长趋势 ;NG流行株对喹诺酮产生耐药性与gyr A和 par C基因双重突变有着密切的关系