Cerenkov luminescence imaging (CLI) is a new method of optical molecular imaging,which has been successfully applied in early clinical trials.However,weak signal intensity and limited ability in tissue penetration have impeded its clinical application.Cerenkov radiation energy transfer imaging and radiation excitation fluorescence imaging were adopted to solve these problems by enabling transformation of some of the blue-weighted Cerenkov luminescence (CL) spectra to red-shifted emissions,or by exciting rare earth particles to emit visible and near infrared light.This article reviews the development of Cerenkov signal enhancement by fluorescence excitation effect.

Fluorescence molecular imaging technology ( FMIT) has been developing rapidly in re?cent years. Following the development of fluorescent probes specifically targeted for gastric cancer, the signal to noise ratio has been improved in preclinical study. By combing with endoscopic technology, a new ima?ging modality called fluorescence endoscopy has been established and it is useful for the detection of gastric cancer in preclinical study. FMIT might be a promising modality in the clinical diagnosis of gastric cancer. This review summarizes the application of FMIT in preclinical studies of gastric cancer.

Objective To explore the feasibility of high?resolution micro?endoscopy for diagnosis of gastric cancer. Methods A retrospective analysis of HRME pictures of gross specimen of gastric carcinoma of 20 cases of gastric cancer and normal gastric mucosa was made. Picture characteristics were studied and the HRME diagnostic criteria for normal gastric mucosa and gastric cancer tissues were developed. Based on the diagnostic criteria, a prospective study on gastric biopsy specimens of 64 cases of suspected gastric carci?noma was conducted and the diagnostic value of HRME for gastric carcinoma was evaluated by comparing HRME pre?diagnostic results with pathological findings. Results In the superficial layer of the fundic muco?sa, numerous regularly branched arranged glands as well as oval or elongated openings of the gastric pits and linear peripheral cracks were visible;the nuclei were arranged regularly. In the superficial layer of the antral mucosa, irregular or tubular openings of the gastric pits and cracked glandular cavities were visible, with the cells surrounding the gastric pits regularly arranged and the nuclei small and densely distributed. In the gas?tric carcinoma, nuclei sizes were different, arranged messy. Gland sizes were various, with unclear structure or glandular structures that could not be observed. Structure of gastric pits was damaged and normal gastric pits disappeared. After HRME imaging was performed on 64 cases of gastric biopsy specimens, the sensitivi?ty, specificity, accuracy, negative predictive value and positive predictive value of HRME diagnosis of gastric carcinoma were 96?4%( 53/55 ) , 88?9%( 8/9 ) , 95?3%( 61/64 ) , 98?1%( 53/54 ) and 80?0%( 8/10) respectively. Conclusion HRME, a new and instant pathological imaging tool with low price and simple operation, can distinguish normal gastric mucosa and gastric cancer tissue clearly, with a high diagno?sis value for gastric cancer.

Objective To investigate the feasibility of high?resolution microendoscopy( HRME) im?aging for animal gastrointestinal mucosa. Methods Mucosal tissues were harvested from the stomach, small intestine, and large intestine of Japanese big?ear white rabbits. The effects of HRME imaging of different lo?cations such as the gastric antrum and fundus, small intestine and large intestine were observed, and those of different exposure time were compared.Accuracy of HRME imaging was compared with pathology. Results The specific tissues of the gastrointestinal mucosa could be clearly distinguished from the HRME images. In the superficial layer of the fundic mucosa, numerous closely arranged glands as well as oval or elongated branched openings of the gastric pits and linear peripheral cracks were visible;the nuclei were arranged reg?ularly. In the superficial layer of the antral mucosa, irregular or tubular openings of the gastric pits and cracked glandular cavities were visible, with the cells surrounding the gastric pits regularly arranged and the nuclei small and densely distributed. In the superficial layer of the small intestine mucosa, stereoscopic thick?finger?shaped villi cluster was visible. The intervillous spaces were crack?like, and the surface was cov?ered by regularly arranged reflective, absorptive cells. In the superficial layer of the large intestine mucosa, many regularly arranged daisy?like round crypts of uniform size, as well as reflective, goblet cells surrounding the crypt and the interval space between crypts were visible. When the exposure time increased, the nuclei became brighter. An excellent correlation was noted between the results of histologic examination and those obtained by using HRME. Conclusion HRME can produce accurate images of the animal gastro?intestinal mucosae and may be a novel technique for further studies of human gastrointestinal pathology.

Objective To explore and evaluate the method and feasibility of applying the contrast agent fluorescein sodium to enhance the efficiency of Cerenkov radiation energy transfer (CRET).Methods Fluorescein sodium was employed as the energy transfer receptor of 18 F-FDG Cerenkov radiation (CR) to achieve stronger signal.18F-FDG was mixed with fluorescein sodium of different concentrations:0.05,0.10,0.20,1.00,2.00,4.00,8.00 mmol/L.Optical signal strength was quantified by ROI analysis.The influence of fluorescein sodium concentration on CRET efficiency and the optimal concentration that could achieve most optical signal augmentation were studied.The optimal concentration of fluorescein sodium was mixed with 1.85-11.10 MBq 18F-FDG for CLI.Linear regression was performed to investigate the range of 18F-FDG dose with most optical signal augmentation and the influence of 18F-FDG dose on CRET efficiency.A tumorbearing nude mouse was imaged after intravenous injection of 18F-FDG and then imaged again after injection of fluorescein sodium post 18 F-FDG injection.These two sets of images were compared to evaluate the CRET efficiency in vivo.Results In vitro study showed that 1.00 mmol/L fluorescein sodium was the optimal concentration for 18F-FDG dose ranging from 1.85 MBq to 11.10 MBq.The signal from 18F-FDG mixed with fluorescein sodium was 3.7 times stronger than that from 18F-FDG alone.Experiment in vivo suggested that 18F-FDG mixed with fluorescein sodium could effectively enhance the signal strength by CRET.Conclusion 18F-FDG mixed with fluorescein sodium may improve the efficiency of CRET,therefore,can enhance the signal strength,reduce the exposure time and achieve better signal to noise ratio.

Objective To summarize the picture features of high resolution micro-endoscopy (HRME) for normal gastrointestinal mucosa. Methods We select 10 cases' normal esophageal mucosa, gastric and duodenal mucosa, in-testinal mucosa and colonic mucosal biopsies for this study, use HRME to observe the specimens and describe the features of different parts of the digestive tract normal mucosa according to the collected HRME pictures. Results After HRME imaging, all specimens were sent to pathological examination. We obtained 1 284 HRME pictures for 50 cases of biopsy specimens, 400 pictures were selected for results analysis after screening. HRME image charac-teristics of different parts of the digestive tract normal mucosa are as follows. Esophageal mucosa: cell arrangement rules, round and bright nucleus, the same size, nuclear spacing normal, the number of cells per field in basically are the same. Fundic mucosa: numerous closely arranged glands as well as oval or elongated branched openings of the gastric pits and linear peripheral cracks were visible; the nuclei were arranged regularly. Antral mucosa: irregular or tubular openings of the gastric pits and cracked glandular cavities were visible, with the cells surrounding the gastric pits regularly arranged and the nuclei small and densely distributed. Duodenal mucosa:visible villi was large fingers,on both sides of lint jagged depression, stereoscopic obviously, a cluster-like arrangement and the gap was crack-like. Intestinal mucosa:villous structures wider gap is wider, less than the number of the duodenum. Colonic mucosa:the nucleus of the same size, shape rules, round or oval and daisy-like glandular structures. All specimens were confirmed normal mucosa by pathology. Conclusion HRME can accurately identify the different parts of the diges-tive tract normal mucosa and it has a high consistency compared with pathological results.

The patients undergoing gastroscope and enteroscopy examination were respectively divided into gastric intestinal metaplasia group (n = 397) and non gastric intestinal metaplasia group (n = 360),and the differences in size,number,location and dysplasia of colonic polyps between the two groups were compared. In GIM group,the polyps incidence after classification of polyp size and colonic dysplasia was significantly higher than that in non GIM group (P < 0. 05),while the number and location of colonic polyps were no significant difference between two groups. By the logistic regression analysis,more than 50 years old of age,male,HP infection,the diameter of polyps are larger than 2. 0 cm,or dysplasia showed high possibility to appear gastric intestinal metaplasia (OR > 1,P< 0. 05),the diameter of colonic polyps are 1. 0 ～ 2. 0 cm which showed high possibility to non intestinal metaplasia (OR < 1,P < 0. 05),and there was no significant difference between the two groups in the incidence of GIM in colonic polyps less than 0. 5 cm or 0. 5 ～ 1. 0 cm in diameter. Not only age,gender and HP infection were related to the occurrence of IM,but the risk of GIM increased in patients with colonic polyps' diameter more than 2. 0 cm and dysplasia. Those who found colonic polyps > 2. 0 cm in diameter and polyps with dysplasia were suggested to undergo gastroscopy in order to find GIM early and follow up to improve the detection rate of early gastric cancer.

Objective To study the expression levels and clinical significance of nerve growth factor(NGF)and Syncytin-1 in ser-um and placental tissues of pregnant women with severe preeclampsia(SPE).Methods A total of 90 pregnant women who underwent ce-sarean delivery in the Department of Obstetrics,the Affiliated Hospital of Xuzhou Medical University in December 2021 to June 2022 were selected,and they were divided into 30 cases of early-onset SPE(early-onset group),30 cases of late-onset SPE(late-onset group),and 30 cases of normal women in the same period(control group).The maternal blood and placental tissues of the three groups were collected,and the expression levels of NGF and Syncytin-1 in each group were detected by enzyme-linked immunosorbent assay(ELISA)and immunohistochemical(IHC)staining,and their clinical significance was analyzed.Results The results of the ELISA showed that compared with healthy pregnant women in the third trimester,the expression of NGF and Syncytin-1 in the serum of pregnant women with SPE was reduced,and the early-onset group was lower than those in the late-onset group(P<0.05).The results of IHC staining showed that compared with healthy pregnant women in the third trimester,the expression levels of NGF and Syncytin-1 in pla-cental tissues were reduced in pregnant women with SPE,early-onset group was lower than those in the late-onset group(P<0.05).Conclusion The expression of NGF and Syncytin-1 in serum and placental tissues of the three groups of pregnant women was succes-sively reduced,and the expression was successively reduced in normal pregnant women,late-onset SPE and early-onset SPE,which may be involved in the occurrence and development of SPE by affecting the normal development of the placenta.

Surgical removal of tumor and metastatic lymph nodes are important for the prognosis of patients.Optical intraoperative navigation can achieve real-time tumor location and border recognition,providing an effective way to guide tumor removal and achieve intraoperative navigation precisely.Cerenkov luminescence imaging(CLI)as a nuclide optical imaging method,which combines the advantages of optical imaging and radionuclides,has opened up a new way of navigation in optical surgery.This article reviews the progress of CLI in intraoperative navigation.

Objective To investigate the value of high resolution microendoscopy ( HRME ) for assessment of mucosal healing in patients with ulcerative colitis ( UC ) during clinical remission. Methods A total of 30 UC patients were randomly selected to collect HRME images. Pathological results were used as the gold standard to establish the diagnostic criteria of HRME on evaluation of colonic mucosal status. And then a prospective study was performed on 67 patients, who underwent standard endoscopy to evaluate colonic mucosal status and obtain biopsy specimens. The specimens were collected for HRME imaging. The accuracy of standard endoscopy and HRME in assessing ulcerative colonic mucosal healing was compared. Results According to the gland morphology, gland arrangement, gland opening and inflammatory cell infiltration, the HRME criteria for assessing UC mucosal status were formulated and divided into 0-3 grades with 4 levels. The prospective study of 67 patients with 113 sites showed that the sensitivity, specificity, positive predictive value, and negative predictive value of standard endoscopy for assessing mucosal healing in UC patients were 44. 68％ ( 21/47 ) , 90. 91％ ( 60/66 ) , 77. 78％ ( 21/27 ) , and 69. 77％ ( 60/86 ) , respectively, and the corresponding indicators of HRME imaging was 87. 23％ (41/47), 95. 45％ (63/66), 93. 18％ (41/44), and 91. 30％ (63/69), respectively. Compared with pathological results, the Kappa value of the consistency test of standard endoscopy and HRME imaging were 0. 379 and 0. 835, respectively ( both P<0. 05) . Conclusion HRME can achieve real-time virtual pathological imaging of colonic mucosa for UC patients, which is more accurate than standard endoscopy for assessing mucosal healing.