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31.
Summary Endothelia of the anterior cerebral arteries in rats aged 1 to 3 days were studied. Thin (about 50–90 Å) and thick (about 100–110 Å) filaments are present in the endothelia. Numerous spherical- or rod-shaped bodies, measuring approximately 0.07 to 0.3 m in diameter and up to 0.6 m in length occur in the endothelial cells. These bodies contain a tubular structure. The diameter of the individual tubules is about 200 Å. The present observations suggest that spherical- or rod-shaped inclusions are first synthesized in the rough endoplasmic reticulum and thereafter these materials are transported into the Golgi complex for maturation. A small number of the inclusions, however, may originate directly from the rough endoplasmic reticulum and not pass through the Golgi apparatus.A part of this study was demonstrated at the 70th Versammlung der Anatomischen Gesellschaft in Düsseldorf, April, 1–5, 1975The author thanks Mr. Tatsuro Fukushima for preparation of photographs  相似文献   
32.
Quantitative assays for the morphological transformation of 3T3 Swiss mouse cells by herpes simplex type 2 virus (HSV-2) were employed to examine the effect on cell transformation of chemical carcinogens and suspected carcinogens. Exposure of the cells to the chemical compound, followed by virus infection, resulted in enhancement of transformation when compared to that observed with chemical or virus alone. Enhancement occurred in tests utilizing either UV light-inactivated HSV-2 (strain 333) or a temperature-sensitive (ts) mutant of HSV-2 [A8(293)]. A series of seven ts-mutants were tested and exhibited varying degrees of transformation. Enhancement of transformation occurred in cells treated with hydrazine (HZ) and 1,2-dimethylhydrazine (SDMH). No enhancement occurred when cells were treated with monomethylhydrazine, 1,1-dimethylhydrazine and the jet fuels JP-5, JP-10, RJ-4 and RJ-5. A strong time dependence after treatment was demonstrated with some enhancement seen at 6 h after chemical treatment but the greatest enhancement appeared when virus infection began after 24 h of chemical exposure.  相似文献   
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Several plaque assay techniques employing TN-368 or IPLB-SF 21AE cells were evaluated for their usefulness in detecting and distinguishing MP (many polyhedra) and FP (few polyhedra) plaque variants of Galleria mellonella nuclear polyhedrosis virus. Both plaque morphologies were produced using either cell line. Of the overlays tested, the buffered 0.6% methylcellulose overlay yielded the most plaques and was best suited for titration. It was also the easiest overlay to prepare and use. The largest plaques were obtained using either cell line with the 1.0 or 0.75% agarose overlays. Plaque variants were most easily distinguished under 1.0 or 0.75% agarose overlays with IPLB-SF 21 cells. The 0.9% MC overlay was the only overlay which did not allow detection of FP plaques. However, FP plaques were detected using a buffered modification of this overlay. It is concluded that the FP variant of G. mellonella NPV is not a host-dependent phenomenon, and that its detection can be influenced by overlay formulation.  相似文献   
35.
Monensin blocks endocytosis of vesicular stomatitis virus   总被引:8,自引:0,他引:8  
Monensin inhibits the infection of mouse cells by Vesicular Stomatitis Virus (VSV). At low drug concentrations (0.5 μM), endocytosis of VSV is inhibited whereas viral binding is unaffected. Monensin may be useful for analyzing the internalization of other viruses as well as soluble ligands.  相似文献   
36.
Summary Electron microscopic studies of the carotid body of the domestic fowl (Gallus gallus domesticus) have shown Type I and Type II cells combined with axons into compact groups. The many Type I cells in the depths of the organ had a body, containing the nucleus, and an elongated, flared process. Some of the Type I cells in the superficial regions tended to be spindle-shaped. Type I cells were characterised by membrane-bound, dense-cored vesicles about 120 nm in diameter. Type II cells invested the Type I cells and had axons embedded in them as in Schwann cells.The fine structure of the carotid body in the domestic fowl resembles that of the Lovebird (Uroloncha domestica) and of various amphibia and mammals. The possibility is discussed that the Type I cells may have a chemoreceptor or a general secretory function, or even both pathway for functions together. The main role of the Type II cells seems to be to provide a of these axons leading to or from Type I cells.The authors are grateful to Mr. R. P. Gould of the Department of Anatomy, Middlesex Hospital Medical School for permission to use some of his and Dr. Hodges' original material in the illustrations. Dr. Hodges also wishes to thank the A.R.C. and the University of London Central Research Fund for financial assistance. We are also most appreciative of the photographic assistance of J. Geary.  相似文献   
37.
Coronary artery disease (CAD) is one of the biggest threats to human life. Circulating microRNAs (miRNAs) have been reported to be linked to the pathogenesis of CAD, indicating the possible role in CAD diagnosis. The present study aimed to explore the expression profile of plasma miRNAs and estimate their value in diagnosis for CAD. 67 Non‐CAD control subjects and 88 CAD patients were enrolled. We conducted careful evaluation by RT‐PCR analysis, Spearman rank correlation coefficients analysis, Receiver Operating Characteristic (ROC) curves analysis and so on. The plasma levels of six miRNAs known to be related to CAD were measured and three of them showed obvious expression change. Circulating miR‐29a‐3p, miR‐574‐3p and miR‐574‐5p were all significantly increased. ROC analysis revealed the probability of the three miRNAs as biomarkers with AUCs (areas under the ROC curve) of 0.830, 0.792 and 0.789, respectively. They were significantly correlated with each other in CAD patients, suggesting the possibility of joint diagnosis. The combined AUC was 0.915, much higher than each single miRNA. Therefore, our study revealed three promising biomarkers for early diagnosis of CAD. The combination of these miRNAs may act more effectively than individual ones for CAD diagnosis.  相似文献   
38.
The current standard biomarker for myocardial infarction (MI) is high‐sensitive troponin. Although powerful in clinical setting, search for new markers is warranted as early diagnosis of MI is associated with improved outcomes. Extracellular vesicles (EVs) attracted considerable interest as new blood biomarkers. A training cohort used for diagnostic modelling included 30 patients with STEMI, 38 with stable angina (SA) and 30 matched‐controls. Extracellular vesicle concentration was assessed by nanoparticle tracking analysis. Extracellular vesicle surface‐epitopes were measured by flow cytometry. Diagnostic models were developed using machine learning algorithms and validated on an independent cohort of 80 patients. Serum EV concentration from STEMI patients was increased as compared to controls and SA. EV levels of CD62P, CD42a, CD41b, CD31 and CD40 increased in STEMI, and to a lesser extent in SA patients. An aggregate marker including EV concentration and CD62P/CD42a levels achieved non‐inferiority to troponin, discriminating STEMI from controls (AUC = 0.969). A random forest model based on EV biomarkers discriminated the two groups with 100% accuracy. EV markers and RF model confirmed high diagnostic performance at validation. In conclusion, patients with acute MI or SA exhibit characteristic EV biomarker profiles. EV biomarkers hold great potential as early markers for the management of patients with MI.  相似文献   
39.
Numerous studies have demonstrated that thioredoxin-interacting protein (TXNIP) expression of peripheral blood leucocytes is increased in coronary artery disease (CAD). However, the molecular mechanism of this phenomenon remained unclear. DNA methylation plays important roles in the regulation of gene expression. Therefore, we speculated there might be a close association between the expression of TXNIP and methylation. In this study, we found that compared with controls, DNA methylation at cg19693031 was decreased in CAD, while mRNA expressions of TXNIP and inflammatory factors, NLRP3, IL-1β, IL-18, were increased. Methylation at cg19693031 was negatively associated with TXNIP expression in the cohort, THP-1 and macrophages/foam cells. Furthermore, Transwell assay and co-cultured adhesion assay were performed to investigate functions of TXNIP on the migration of THP-1 or the adhesion of THP-1 on the surface of endothelial cells, respectively. Notably, overexpressed TXNIP promoted the migration and adhesion of THP-1 cells and expressions of NLRP3, IL-18 and IL-1β. Oppositely, knock-down TXNIP inhibited the migration and adhesion of THP-1 and expressions of NLRP3, IL-18. In conclusion, increased TXNIP expression, related to cg19693031 demethylation orientates monocytes towards an inflammatory status through the NLRP3 inflammasome pathway involved in the development of CAD.  相似文献   
40.
目的:探究Interlock可解脱弹簧圈在脾动脉瘤的腔内治疗中的应用价值。方法:回顾性分析2016年2月至2019年2月于本中心使用Interlock可解脱弹簧圈治疗的36例脾动脉瘤患者的临床资料,包括10例男性,26例女性,31例真性动脉瘤,5例假性脾动脉瘤,术前均行超声或CTA明确诊断。术中栓塞后,立即血管造影以明确技术成功率。围手术期及术后2周、3个月和6个月监测血常规、胰淀粉酶和主动脉CTA,观察并发症的发生情况。结果:6例患者弹簧圈栓塞动脉瘤远近端及瘤腔,其余仅栓塞脾动脉瘤瘤腔。术中DSA血管造影提示即刻脾动脉瘤栓塞闭塞率为97%以上,术中共使用128枚Interlock弹簧圈,其中104枚为钻石型,24枚为普通2D型。弹簧圈平均直径为6.3±4.2(2-12)mm,平均长度为16±13.5(3-32)mm,瘤体平均尺寸为40.6±12.5(15-70) mm。围手术期无并发症发生。平均随访10.0±3.2(6-15)个月,1月后2例出现脾梗死,7例发生轻微腹痛及低热等症状,所有病例均未见瘤腔再通和瘤体增大。结论:Interlock可解脱弹簧圈可以安全有效地治疗脾动脉瘤,但其远期疗效需长期随访观察。  相似文献   
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