Smartphone-based multimodal tethered capsule endoscopic platform for white-light,narrow-band,and fluorescence/autofluorescence imaging

Multimodal low-cost endoscopy is highly desirable in poor resource settings such as in developing nations. In this work, we developed a smartphone-based low-cost, reusable tethered capsule endoscopic platform that allows white-light, narrowband, and fluorescence/autofluorescence imaging of the esophagus. The ex-vivo studies of swine esophagus were performed and compared with a commercial endoscope to test the white-light imaging capabilities of the endoscope. The efficacy of the capsule for narrow-band imaging was tested by imaging the vascularization of the tongue. To determine the autofluorescence/fluorescence capability of the endoscope, fluorescein dye with different concentrations was imaged. Furthermore, swine esophagus injected with fluorescein dye was imaged using the fluorescence/autofluorescence and the white-light imaging modules, ex-vivo. The overall cost of the capsules is approximately 12 €, 15 €, and 42 € for the white light imaging, the narrow-band imaging, and the fluorescence/autofluorescence imaging respectively. In addition, the cost of the laser source module required for the narrow-band imaging and the fluorescence/autofluorescence imaging is approximately 218 €. This device will open the possibility of imaging the esophagus in underprivileged areas.     

窄带成像内镜、染色内镜及常规内镜模式诊断结直肠增生性病变的应用价值比较研究

目的:探讨窄带成像内镜(NBI)、染色内镜及常规内镜模式鉴别诊断非肿瘤性、肿瘤性结直肠增生性病变的应用价值。方法:选择2017年2月至2019年3月西安市中心医院消化科收治的结直肠增生性病变患者,均行NBI、染色内镜、常规内镜检查。比较三种模式图像清晰度以及鉴别诊断非肿瘤性、肿瘤性结直肠增生性病变的效能。结果:NBI、染色内镜模式图像质量评分分布优于常规内镜(P<0.05),NBI图像质量评分分布优于染色内镜模式(P<0.05)。以病理结果为准,常规内镜结直肠增生性病变检出率73.13%,NBI 91.04%,染色内镜96.26%,NBI、染色内镜结直肠增生性病变检出率高于常规内镜(P<0.05),NBI、染色内镜比较无统计学差异(P>0.05)。NBI模式下检测NBI分型与病理组织学结果一致性较好(kappa值=0.801,P<0.05)。NBI、染色内镜诊断肿瘤性结直肠增生性病变的灵敏度、特异度、阳性预测值、阴性预测值、准确度均明显高于常规内镜,染色内镜、NBI、常规内镜诊断肿瘤性结直肠增生性病变的曲线下面积(AUC)分别为0.844(95%CI:0.812~0.956)、0.921(95%CI:0.860~0.982)、0.750(95%CI:0.651~0.848)。结论:NBI、染色内镜在鉴别非肿瘤性和肿瘤性结直肠增生性病变方面效能相似,均优于常规内镜,NBI分型与病理组织学结果一致性高,更适合结直肠增生性病变的鉴别诊断。     

Fine surface structure of enterotoxemic Escherichia coli O139:K12 strains associated with swine edema disease

The fine structure of the cell surface of seven enterotoxemic Escherichia coli (ETEEC) O139:K12 strains isolated from piglets with edema disease were examined electron microscopically using both the negative-staining method and the freeze-substitution fixation method. Densely packed, fine fibers were observed; they consisted of a capsule layer approximately 25 nm thick around the cell surfaces of strains 107/86, IW-2, ED-3, ED-43, and ED-61, all of which have a capacity to adhere strongly to HEp-2 cells. In contrast, no such structure was observed on the surface of strains RK-O139 or ED-1, both of which adhere only weakly to HEp-2 cells. These results suggest that the capsule structure might be associated with the ability to adhere to HEp-2 cells and, as a result, also potentially play some role in ETEEC infection. Received: 29 April 1996 / Accepted: 13 August 1996