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《Vaccine》2021,39(26):3498-3508
Adenovirus infections are a major cause of epidemic keratoconjunctivitis (EKC), which can lead to corneal subepithelial infiltrates and multifocal corneal opacity. In the current study, we investigated the use of an E1/E3-deleted adenovirus serotype 5 (Ad5) vector as a vaccine administered intramuscularly (IM) or intranasally (IN) against subsequent challenges with a luciferase-expressing Ad5 (Ad5-Luci) vector via eyedrop. We evaluated the adaptive immune response to Ad5 vector vaccination and confirmed a robust polyfunctional CD8 T cell response in splenic cells. Neutralizing Ad5 antibodies were also measured in the sera of vaccinated mice as well as Ad5 antibody in the eye wash solutions. Upon challenge with Ad5-Luci vector 8 weeks post the primary immunization, transduction was significantly reduced by > 70% in the vaccinated mice, which was slightly better in IM- vs. that in IN-vaccinated animals. Resistance to subsequent challenge was observed 10 months post primary IM vaccination, with sustained reduction up to 60% in the Ad5-Luci vector transduction. Passive immunization of naive mice with antisera from IM to vaccinated mice subsequently challenged with the Ad5-Luci vector resulted in approximately 40% loss in transduction efficiency. Furthermore, the mice that received IM immunization with or without CD8 T cell depletion showed > 40% and 70% reductions, respectively, in Ad8 genomic copies after Ad8 topical challenge. We conclude that Ad-vector vaccination successfully induced an adaptive immune response that prevented subsequent Ad transduction in the cornea and conjunctiva-associated tissues in a mouse model of adenovirus keratoconjunctivitis, and that both cellular and humoral immunity play an important role in preventing Ad transduction.  相似文献   
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IntroductionLymph node yield (LNY) in neck dissection has been identified as a prognostic factor in oral cavity cancer. The purpose of this study was to investigate the impact of additional use of optical imaging on LNY in therapeutic ND in oral cancer.MethodsConsecutive patients with oral squamous cell carcinoma with clinical neck metastasis planned for primary tumor resection were randomized to conventional neck dissection or near-infrared fluorescence (NIRF)-guided neck dissection, respectively. In the intervention group, patients were injected with ICG-Nanocoll prior to surgery. Intraoperatively, an optical hand-held camera system was used for lymph node identification. Also, NIRF imaging of the neck specimen was performed, and optical signals were pinned with needle markings to guide the pathological examination. The endpoint of the study was LNY per neck side in levels Ib-III.Results31 patients were included with 18 neck sides in the control group and 18 neck sides in the intervention group for evaluation. During NIRF-guided ND, individual lymph nodes could be identified by a bright fluorescent signal and individual tumor-related drainage patterns could be observed in the neck. The LNY in the intervention group was significantly higher compared to the control group (p = 0.032) with a mean of 24 LN (range: 12–33 LN in levels Ib-III compared to 18 LN (range: 10–36 LN) in the control group, respectively.ConclusionsNIRF-guided ND significantly improved the nodal yield compared to the control group. Intraoperative real-time optical imaging enabled direct visualization of tumor-related drainage patterns within the neck lymphatics.  相似文献   
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目的分析激光消毒根管,防治根管治疗期间急症(endodonticinterappointmentemergencies,EIAE)发生的效果。方法慢性根尖周炎、慢性牙髓炎、牙髓坏死患者189例,随机分为激光组94例和对照组95例。激光组用激光消毒根管后一次性完成根管治疗;对照组直接行一次性完成根管治疗。对激光防治EIAE的效果进行临床评估。结果EIAE的发生率激光组为9.6%,对照组为35.8%,两组比较差异有显著意义(P<0.01)。结论运用激光消毒根管能有效地预防和降低根管治疗期间急症的发生。  相似文献   
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BACKGROUND: To evaluate potential differences in light absorbing properties and stability of indocyanine green (ICG) adsorbed to the retinal surface and of ICG dissolved in water and balanced salt solution. METHODS: The retina of four human donor eyes was prepared by removing the vitreous from the retinal surface. The inner surface of the specimen was covered with two to three drops of a 0.05% or 0.15% ICG solution respectively. After 1 min, the dye was removed by careful irrigation using BSS plus. The retinal specimens were then investigated by diffuse reflection spectroscopy (UV/VIS/NIR Spectrometer Lambda 900/Perkin Elmer equipped with a PELA-1020 integrating sphere accessory) and their absorption evaluated by the Kubelka-Munk function. To control the sensitivity of the setting, diffuse reflectance spectra of ICG adsorbed to a cellulose membrane and Al(2)O(3) were measured. For comparison, absorption spectra of ICG dissolved in water and BSS plus solution were measured in relation to ICG concentration and time using an UV/VIS/NIR Spectrometer Lambda 900/Perkin Elmer. RESULTS: On the retinal surface, absorption spectra exhibited a steep increase of absorption beginning at 620 nm, with a maximum at 736 nm (0.05%) and a shoulder at 745 (0.15%) and a second maximum at approximately 800 nm for both concentrations. Repeated measurement of the retinal surface 13 days after the ICG exposure revealed no changes in the position of the maxima as compared to the initial measurements. Light absorbing properties of ICG on cellulose or Al(2)O(3) are similar to those seen on the retinal surface with respect to the pattern and location of absorption maxima. In contrast, ICG dissolved in water or BSS plus disclosed variations in absorption characteristics depending on dye concentration, solute and time of measurement. CONCLUSIONS: Absorption characteristics and stability of ICG bound to the retinal surface could be of relevance when investigating potential pathomechanisms of ICG related toxicity, which might be related not only to intraoperative but also to postoperative light exposure of patients after intravitreal use of ICG.  相似文献   
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目的 评价准分子激光原位角膜磨镶术(excimer laser in situ keratomileusis,LASIK)治疗儿童远视性屈光参差的疗效.方法 使用美国Summit公司的SVS Apex plus准分子激光系统及Moria公司的微型板层角膜切割系统(LSK),对8例9~14岁远视性屈光参差患者进行LASIK手术,术后进行双眼视训练和系统的弱视治疗.结果 术后裸眼视力和矫正视力明显提高,术前平均最佳矫正视力0.23,术后6个月平均最佳矫正视力0.65;屈光度明显降低,但平均仍残留 2.81D;8例患者全部建立同时视和融合功能,6例有立体视功能.结论 LASIK治疗儿童远视性屈光参差安全有效,可明显提高视力,恢复和建立双眼视功能.  相似文献   
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