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1.
Acta Pharmaceutica Sinica ; (12): 169-177, 2022.
Article in Chinese | WPRIM | ID: wpr-913161

ABSTRACT

During fluorescence-guided cancer surgery, ultra-pH sensitive (UPS) fluorescent nanoprobes has multiple advantages such as real-time imaging procedures, ultra-high imaging sensitivity as well as broad tumor detection specificity. UPS nanoprobes stay at "OFF" state at higher pH and turn into "ON" state at lower pH with emission of strong fluorescence. Moreover, the transition pH points (transition pH point, pHt) can be precisely controlled by structural-based strategy. One of the previously-reported UPS nanoprobes showed good imaging effect. However, it is still not clear about the effect of pHt on cancer imaging efficiency of UPS nanoprobes and to further identify the optimal UPS. In this study, we synthesized a series of UPS nanoprobes with pHt at 4.5, 6.2, 6.6, 7.8 by adjusting the hydrophobic blocks of UPS polymers. Each nanoprobe showed excellent stability in "OFF" state by dynamic light scattering and uniform morphology observed by transmission electron microscopy. In vitro imaging characterized the ultra-pH sensitive fluorescence transition of each probe. In vivo imaging results identified two UPS nanoprobes (NP-6.2 and NP-6.6) with superior tumor imaging effect. All animal experiments in this study were approved by the Animal Ethics Committee of Peking University Health Science Center and were strictly followed by the welfare regulations of laboratory animals of Peking University Health Science Center. Therefore, this study has explored the effect of pHt on the cancer imaging efficiency of UPS nanoprobes and provides a new idea for design of the other cancer microenvironment-responsive polymers.

2.
Article in Chinese | WPRIM | ID: wpr-940303

ABSTRACT

ObjectiveTo establish a simple, fast and accurate method for locating the volatile oil in Angelicae Sinensis Radix based on frozen section and fluorescence imaging technology, and to reveal the distribution and accumulation of volatile oil in the roots of this herbal medicine. MethodAngelicae Sinensis Radix was used as the research material, the best frozen section conditions for the research material were established by comparing the effects of different cryoprotectants on the quality of frozen sections of Angelicae Sinensis Radix. The suitability of Sudan Ⅲ chemical staining and fluorescence localization for positioning the volatile oil were compared according to the loss of volatile oil and the complexity of operation process. ResultA new method for evaluating the quality of frozen sections of Angelicae Sinensis Radix was established. According to the evaluation equation, it was found that the highest score was obtained when the head, body and tail positions of Angelicae Sinensis Radix were treated with 20% glycerol, 15% glycerol and 20% sucrose, respectively. There was yellowish-brown oily substance in the oil chambers of phelloderm and secondary phloem, and oil canal of the secondary xylem of Angelicae Sinensis Radix, which could be stained orange red or orange yellow by Sudan Ⅲ, and there was green spontaneous fluorescence in the same part under the fluorescence microscope. ConclusionThe relatively complete section of Angelicae Sinensis Radix can be obtained after being treated with cryoprotectant. The volatile oil exists in the oil chambers of phelloderm and secondary phloem, and oil canal of the secondary xylem of Angelicae Sinensis Radix. This study can provide reference for observation of the accumulation sites of volatile oil in other plants.

3.
Chinese Journal of Oncology ; (12): 450-454, 2022.
Article in Chinese | WPRIM | ID: wpr-935236

ABSTRACT

Objective: Local recurrence is the main cause of treatment failure in patients with oral squamous cell carcinoma (OSCC). This study was proposed to investigate the feasibility of near infrared fluorescence (NIF) via indocyanine green (ICG) for monitoring surgical marginal in operation for OSCC patients. Methods: In 35 patients with OSCC treated surgically in the Department of Oral and Maxillofacial Surgery, Nanjing University School of Medicine, from January 2019 to June 2020, ICG (0.75 mg/kg) was administered intravenously via elbow vein at (12±1) hours before surgery, and NIF was performed intraoperatively on the surgical field and the cut edge of the surgically excised specimen, and fluorescence intensity was measured for OSCC tissue and normal oral mucosa, abnormal fluorescence signals were taken and subjected to rapid cryopathological examination. Correlation between NIF tumor boundary grading and pathological tumor boundary grading was analyzed by Spearman correlation analysis. Results: Clear ICG NIF was obtained for tumor lesions in all 35 patients, with a positive rate of 100%. The fluorescence intensity of OSCC tissue was (412.73±146.56) au, which was higher than that of normal oral mucosa tissue [(279.38±82.56) au, P<0.01]. Abnormal fluorescence signals were detected at the tumor bed and the cut edge of the surgical resection specimen in 4 patients, of which 2 cases were pathologically confirmed as cancer cell residue and 2 cases as inflammatory cell infiltration. The rate of positive detection of cut margins using ICG NIF technique in OSCC was 5.7% (2/35). Twenty of the 35 OSCC patients had grade 1, 11 of grade 2, and 4 of grade 3 tumor borders revealed by NIF of surgical resection specimens, which was positively correlated with pathological tumor border (r=0.809, P<0.001). Conclusions: ICG NIF technique can effectively detect the residual cancer cells at the incision margin, which is of great clinical value in reducing local recurrence of OSCC after surgery due to intraoperative cancer residue.


Subject(s)
Carcinoma, Squamous Cell/surgery , Head and Neck Neoplasms , Humans , Indocyanine Green , Margins of Excision , Mouth Neoplasms/surgery , Neoplasm, Residual , Optical Imaging/methods , Squamous Cell Carcinoma of Head and Neck/surgery
4.
Article in Chinese | WPRIM | ID: wpr-932792

ABSTRACT

Objective:To study the glypican 3 (GPC3) fluorescent probe imagings in hepatocellular carcinoma (HCC) tissues and to determine its prognostic value in HCC patients.Methods:The data of 87 patients who were treated at the Affiliated Hospital of Southwest Medical University from January 2019 to August 2020 were retrospectively analyzed. There were 75 males and 12 females, with the age of (56.1±11.9) years. The expressions of GPC3 were measured by immunohistochemistry and by the fluorescent probe. The results obtained by these two tests were compared. Patients were followed up for recurrence after hepatectomy. Univariate and multivariate Cox regression analyses were used to analyze factors influencing recurrence-free survival.Results:Detection of the GPC3 expression by GPC3 fluorescence probe was consistent with the results obtained by immunohistochemical studies ( Kappa=0.84, P<0.001). The positive rates of GPC3 fluorescent probe was 79.3%(69/87), compared with 80.4%(70/87) by immunohistochemistry studies, with no significant difference between the two groups ( P>0.05). The patients were then divided into the low differentiation group ( n=30) and the middle high differentiation group ( n=57) by the degrees of tumor differentiation. The fluorescence intensity in the low differentiation group was 134.4(128.0, 144.7) a. u. which was significantly different from the middle high differentiation group of 84.8(0, 108.5)a.u. ( Z=-7.52, P<0.001). The median fluorescence intensity of 87 patients with HCC was 108.6 a. u.. Multivariate Cox regression analysis showed that patients with a GPC3 fluorescence intensity ≥108.6 a. u. ( HR=2.07, 95% CI: 1.21-3.53, P=0.008) had a significant increased risk of recurrence after hepatectomy. Conclusion:The expressions of GPC3 in HCC were consistent between the studies by using either a GPC3 specific fluorescent probe or immunohistochemistry studies. A GPC3 fluorescence intensity ≥108.6 a. u. was a risk factor of recurrence after hepatectomy in patients with HCC.

5.
Article in Chinese | WPRIM | ID: wpr-932782

ABSTRACT

Objective:This meta-analysis was conducted to systematically evaluate the short-term efficacy and safety of indocyanine green fluorescence imaging guided laparoscopic liver tumor resection (FIGLTR).Methods:A systematic search was made for the literature on indocyanine green fluorescence image-guided laparoscopic hepatectomy in randomized, semi-randomized controlled trials and observational studies, and manually search published materials and conference papers in Chinese and English and trace references included in the literature. The retrieval period was up to September 2021. The quality of included studies was evaluated, then the meta-analysis was conducted using Review Manager 5.1 software.Results:Ten studies were included with 803 patients, including 341 in the FIGLTR group and 462 in the non-FIGLTR group. Meta results showed that: Compared to the traditional resection group, indocyanine green fluorescence imaging can significantly shorten the operative time ( MD=-22.61, 95% CI: -34.20--11.03, P<0.001), reduce intraoperative bleeding ( MD=-49.17, 95% CI: -84.99--13.36, P<0.01), shorter hospital stay ( MD=-0.89, 95% CI: -7.72--0.06, P<0.05), Improve the removal rate of R 0 edge ( OR=8.80, 95% CI: 1.96-39.44, P<0.05) and reduce the incidence of postoperative complications ( OR=0.55, 95% CI: 0.34-0.87, P<0.05) of laparoscopic liver tumor resection. There were no differences found in portal block time and transfusion rate. Conclusion:Indocyanine green fluorescence imaging technology provides a new way for safe and accurate laparoscopic resection of liver tumors.

6.
Acta Pharmaceutica Sinica B ; (6): 316-325, 2022.
Article in English | WPRIM | ID: wpr-929296

ABSTRACT

Vanin-1 is an amidohydrolase that catalyses the conversion of pantetheine into the amino-thiol cysteamine and pantothenic acid (coenzyme A precursor), which plays a vital role in multiple physiological and pathological processes. In this study, an enzyme-activated near-infrared (NIR) fluorescent probe (DDAV) has been constructed for sensitively detecting Vanin-1 activity in complicated biosamples on the basis of its catalytic characteristics. DDAV exhibited a high selectivity and sensitivity toward Vanin-1 and was successfully applied to the early diagnosis of kidney injury in cisplatin-induced kidney injury model. In addition, DDAV could serve as a visual tool for in situ imaging endogenous Vanin-1 in vivo. More importantly, Enterococcus faecalis 20247 which possessed high expression of Vanin-1 was screened out from intestinal bacteria using DDAV, provided useful guidance for the rational use of NSAIDs in clinic. Finally, oleuropein as a potent natural inhibitor for Vanin-1 was discovered from herbal medicines library using a high-throughput screening method using DDAV, which held great promise for clinical therapy of inflammatory bowel disease.

7.
Article in English | WPRIM | ID: wpr-929234

ABSTRACT

Ubiquitin-proteasome system (UPS) plays an important role in neurodegenerative diseases, such as Alzheimer's disease (AD), Parkinson's disease (PD), and Huntington's disease (HD). The discovery of UPS activators for anti-neurodegenerative diseases is becoming increasingly important. In this study, we aimed to identify potential UPS activators using the high-throughput screening method with the high-content fluorescence imaging system and validate the neuroprotective effect in the cell models of AD. At first, stable YFP-CL1 HT22 cells were successfully constructed by transfecting the YFP-CL1 plasmid into HT22 cells, together with G418 screening. The degradation activity of the test compounds via UPS was monitored by detecting the YFP fluorescence intensity reflected by the ubiquitin-proteasome degradation signal CL1. By employing the high-content fluorescence imaging system, together with stable YFP-CL1 HT22 cells, the UPS activators were successfully screened from our established TCM library. The representative images were captured and analyzed, and quantification of the YFP fluorescence intensity was performed by flow cytometry. Then, the neuroprotective effect of the UPS activators was investigated in pEGFP-N1-APP (APP), pRK5-EGFP-Tau P301L (Tau P301L), or pRK5-EGFP-Tau (Tau) transiently transfected HT22 cells using fluorescence imaging, flow cytometry, and Western blot. In conclusion, our study established a high-content fluorescence imaging system coupled with stable YFP-CL1 HT22 cells for the high-throughput screening of the UPS activators. Three compounds, namely salvianolic acid A (SAA), salvianolic acid B (SAB), and ellagic acid (EA), were identified to significantly decrease YFP fluorescence intensity, which suggested that these three compounds are UPS activators. The identified UPS activators were demonstrated to clear AD-related proteins, including APP, Tau, and Tau P301L. Therefore, these findings provide a novel insight into the discovery and development of anti-AD drugs.


Subject(s)
Alzheimer Disease/drug therapy , Humans , Neuroprotective Agents , Optical Imaging , Proteasome Endopeptidase Complex , Ubiquitin
8.
Acta Pharmaceutica Sinica ; (12): 1402-1410, 2022.
Article in Chinese | WPRIM | ID: wpr-924745

ABSTRACT

Effective supplementation of probiotics can be beneficial to intestinal health, but in situ analysis of probiotics activity has rarely been reported. In this study, by coupling fluorescein 5-isothiocyanate (FITC) and 5(6)-carboxytetramethylrhodamine N-succinimidyl ester (5(6)-TAMRA-SE) with D-lysine, two fluorescent D-amino acids (FDAAs) probes were obtained: green probe (fluorescein-D-lysine, FDL) and red probe (TAMRA-D-lysine, TDL). Then, we tried to label the three kinds of probiotics, Lactobacillus acidophilus (LA), Lactobacillus casei (LC) and Veillonella atypica (VA) in vitro. FDAAs was applied to the labeling of intestinal flora in mice, and a method was established to investigate the oral survival rate of three commonly used probiotics. All animal experiments were approved by the Animal Ethics Committee of Guangzhou University of Chinese Medicine. The results show that the two synthetic FDAAs can be non-toxic and 100% for the in vitro labeling of the three probiotics. Known by FDAAs two-step labeling of oral probiotics, the high survival rate of LA was 92.30% ± 1.67%. The survival rates of VA and LC are similar, 84.13% ± 4.06% and 82.27% ± 2.43%, respectively. This study can quickly compare the changes of colonization survival rate of different probiotics in vivo, provide theoretical support for the in situ colonization activity of probiotics in the intestine, and guide the rational drug use of clinical probiotics.

9.
Article in Chinese | WPRIM | ID: wpr-910606

ABSTRACT

Indocyanine green (ICG) fluorescence imaging technology has been applied in laparoscopic surgery. It is possible to highly visualize the tumor cutting edge and liver segment boundary during laparoscopic hepatectomy. Although the application of this technique in liver tumor surgery has become more and more mature, the factors affecting the quality of fluorescence imaging are still not completely clear. In this paper, we analyzed and summarized the effects of different factors such as ICG administration scheme, imaging acquisition, tumor characteristics of patients and preoperative liver function indexes on the quality of intraoperative ICG imaging, in order to provide new ideas and practical experience for clinical practice and research.

10.
Article in Chinese | WPRIM | ID: wpr-910418

ABSTRACT

Objective:To evaluate the skin development and repair process of X-ray radiation damage in rat with non-invasive two-photon excitation fluorescence (TPEF) imaging technology in vivo. Methods:Totally 24 SD rats were randomly divided into four groups including X-ray irradiated group (25, 35 and 45 Gy) and non-irradiation control group. At different times after irradiation, the degree of skin injury was evaluated, and the pathological changes of nicotinamide adenine dinucleotide (phosphate) [NAD(P)H] and collagen fiber fluorescence signals in epidermal cells were detected in vivo by TPEF imaging technology. Results:At 10 d post-irradiation, the skin of irradiation groups showed erythema and desquamation. At 15-20 d post-irradiation, the skin of radiation groups developed progressive exudation, edema and ulcers with increasing radiation dose. On day 25, the skin began to repair in the 25 Gy group, however, the skin of other groups still had exudation and ulcers. On day 10, NAD(P)H fluorescence signal in epidermal cells of irradiation groups decreased and the fluorescence signal of collagen fibers in papillary layer and reticular layer of irradiation groups reduced, which were significantly lower than that of normal control group ( t=24.145, 28.303, 26.989, 6.654, 7.510, 7.997, P<0.05). On day 30, fluorescence signal of NAD(P)H and collagen fibers in epidermal cells and dermis began to repair, the cell from stratum granulosum, stratum spinosum, and stratum basale in the 25 Gy group showed fluorescence signal, the other groups did not show. The fluorescence signal of collagen fibers in the 25 Gy group were gradually increased in papillary layer and reticular layer, however, they were significantly lower than normal control group ( t=115.133, 17.431, P<0.05), the skin of 45 Gy group did not show fluorescence signal of collagen fibers. Conclusions:The damage and repair process of epidermal cells and dermal collagen fiber can be detected noninvasively by TPEF imaging technology after X-ray irradiation in vivo.

11.
Article in Chinese | WPRIM | ID: wpr-908499

ABSTRACT

Near infrared region Ⅱ (NIR-Ⅱ) fluorescence imaging has made progress in clinical application in recent years and has shown a higher image quality, tumor sensitivity and deeper tissue imaging capability compared to near infrared region Ⅰ imaging in liver neoplasms and biliary tract system. As a real-time intraoperative imaging technology, which can provide high signal to background ratio and deeper tissue penetration, NIR-Ⅱ is able to shorten the duration of operation while improve the safety and therapeutic effect of surgery. It has a great prospect and expanding ability. With the development of a bunch of novel NIR-Ⅱ fluorophores, it is expected to play more important roles in hepatocellular carcinoma targeted imaging, evaluation of bile duct perfusion, distal choledochal imaging and so on. The authors review the progress in the application of NIR-Ⅱ fluorescence imaging in hepatobiliary surgery.

12.
Chinese Journal of Biotechnology ; (12): 2678-2687, 2021.
Article in Chinese | WPRIM | ID: wpr-887833

ABSTRACT

Fluorescence imaging has been widely used in the fields of biomedicine and clinical diagnosis. Compared with traditional fluorescence imaging in the visible spectral region (400-760 nm), near-infrared (NIR, 700-1 700 nm) fluorescence imaging is more helpful to improve the signal-to-noise ratio and the sensitivity of imaging. Highly-sensitive fluorescent probes are required for high-quality fluorescence imaging, and the rapid development of nanotechnology has led to the emergence of organic dyes with excellent fluorescent properties. Among them, organic fluorescent probes with the advantages of high safety, good biocompatibility, and high optical stability, are more favorable than inorganic fluorescent probes. Therefore, NIR fluorescence imaging assisted with organic fluorescent probes can provide more structural and dynamic information of biological samples to the researchers, which becomes a hot spot in the interdisciplinary research field of optics, chemistry and biomedicine. This review summarizes the application of NIR organic fluorescent probes in cervical cancer imaging. Several typical organic fluorescent probes (such as indocyanine green, heptamethine cyanine dye, rhodamine and polymer fluorescent nanoparticles) assisted NIR fluorescence imaging and their applications in cervical cancer diagnosis were introduced, and the future development and application of these techniques were discussed.


Subject(s)
Female , Fluorescent Dyes , Humans , Nanoparticles , Optical Imaging , Polymers , Uterine Cervical Neoplasms/diagnostic imaging
13.
Article in English | WPRIM | ID: wpr-880661

ABSTRACT

The preliminary screening of oral cancer mostly depends on the experience of clinicians, The surgical margin of tumor is mostly based on physical examination and preoperative imaging examination. It lacks real-time and objective intraoperative evaluation methods. Indocyanine green (ICG), as a safe and pollution-free organic fluorescent pigments, combined with near-infrared fluorescence imaging can be applied in the screening of early oral cancer, the determination of tumor resection margins, sentinel lymph node biopsy, cervical lymph node dissection, targeted chemotherapy, and other aspects. Near-infrared fluorescence imaging may become a key link in the early diagnosis and accurate treatment for oral cancer in the future.


Subject(s)
Humans , Indocyanine Green , Lymph Nodes , Mouth Neoplasms/therapy , Optical Imaging , Sentinel Lymph Node Biopsy
14.
International Journal of Surgery ; (12): 139-144, 2020.
Article in Chinese | WPRIM | ID: wpr-863289

ABSTRACT

In recent years,the use of fluorescent contrast agents staining to guide surgery has flourished in various fields of surgery under the concept of precision surgery,which is helpful to guide surgery and provide surgeons with actual visible fluorescence imaging.Clinically,fluorescent contrast agent can be used to display tumor's outline with high recognition degree,guide operation in real time,locate lymph node metastasis,detect small metastases,and identify important anatomical structures during the operation to avoid possible side-injury.Great progress has been made in the study of fluorescent contrast agents that can mediate surgery,including the study and surgical application development of classical fluorescent contrast agents such as indocyanine green and methylene blue,etc,as well as the discovery and clinical application of new targeted fluorescent contrast agents such as folate receptor targeting contrast agents,monoclonal antibody based fluorescent targeting contrast agents and intelligent contrast agents,etc.This paper will review the research and surgical application of fluorescent contrast agents in two aspects:classical fluorescent contrast agents and new targeted fluorescent contrast agents.

15.
Article in Chinese | WPRIM | ID: wpr-861555

ABSTRACT

Objective: To explore the value of indocyanine green fluorescence imaging in tumor localization and lymph node dissection in totally laparoscopic distal gastrectomy. Methods: A retrospective cohort study was used. The clinical and pathological data of 126 patients with distal gastric cancer diagnosed through gastroscopy and pathology dated from August 2017 to August 2019 in Peking University Cancer Hospital & Institute was collected. Among these 126 patients, 62 patients underwent laparoscopy with indocyanine green-labeled near-infrared fluorescence (observation group), and 64 patients underwent conventional laparoscopy (control group). The effects of preoperative indocyanine green-labeled, intraoperative endoscopic positioning and lymph node dissection were compared and evaluated between the two groups. Result: The distance of proximal incision margin was measured in patients with stage T1-2 gastric cancer. The observation group vs. the control group: (4.92±1.65 cm vs. 4.76±1.66 cm, P=0.671). Number of second station lymph node dissection of patients with stage T3-4 gastric cancer in the observation group vs. the control group: (11.09±6.19 vs. 8.89± 4.35, P=0.049); the number of damaged lymph nodes in the observation group vs. the control group: (0.74±0.46 vs. 1.27±1.22, P= 0.009). Conclusions: The preoperative indocyanine green-fluorescence imaging in patients with stage T1-2 gastric cancer can accurately mark the tumor boundary, and its tumor localization effect is comparable with intraoperative gastroscopy in the surgery, which can guide the decision of the appropriate resection line during total laparoscopic surgery. Indocyanine green in the lymphatic navigation of T3-4 gastric cancer can guide the operation precisely and completely in the lymph node dissection, increase the number of lymph nodes dissection, and reduce the damage of lymph nodes during the operation.

16.
Article in Chinese | WPRIM | ID: wpr-847673

ABSTRACT

BACKGROUND: Clinical systems caused by degenerative disc disease are one of the largest health worldwide problems. Changes of biomechanics of lumbar disc play important difference in the development of degenerative disc disease OBJECTIVE: To briefly describe the anatomical and histological features of lumbar Intervertebral discs, and to review the research methods and progress in lumbar intervertebral disc biomechanics in recent years. METHODS: A computer-based online retrieval of CNKI, Wanfang, VIP, PubMed, Elsevier and Web of Science databases was conducted with the keywords of “biomechanics, intervertebral disc, lumbar spine, finite element analysis, imaging, MRI, BFIS, DSXS” in Chinese and English, respectively. The articles were firstly screened by reading the title and abstract, and 67 eligible articles were included for result analysis after excluding irrelevant articles. RESULTS AND CONCLUSION: (1) The research on lumbar disc biomechanics is mainly divided into in vitro research and in vivo research. (2) In vitro studies include animal specimens, human cadavers and finite element analysis. The design of in vitro experiment is flexible and maneuverable, but it is separated from human physiological environment and the mechanical properties of materials are different. After long-term verification, the applicability of the experiment in human body is screened out. (3) In vivo studies mainly record the changes of the force shape of disc movement in vivo in real time through imaging methods, which is real and reliable. However, limited by the development of imaging technology, it needs to be used reasonably. The new biplanar fluorescent imaging system and dynamic stereo-radiography system have unique advantages in this field, which attracted much attention.

17.
Article in Chinese | WPRIM | ID: wpr-847506

ABSTRACT

BACKGROUND: Various cell therapy products have been approved by clinical trials worldwide, and cell therapies such as stem cell therapy and adoptive immunotherapy have attracted much attention. Real-time observation and imaging in vivo can visualize the distribution of cells, track cell movement, monitor cell viability, and observe the cell migration and growth. Many imaging technologies can visualize cells in vivo, such as ultrasound, optics, MRI and nuclear imaging, and these methods need to correspond to different labeling and detection strategies. Each strategy has its own advantages and disadvantages. OBJECTIVE: To review the principle and development of different tracking methods, and their application in animals and humans. METHODS: PubMed, Google Scholar, Web of Science and CNKI databases were searched with the keywords of “cell tracking, in vivo cell tracking, PET imaging, MRI, optical imaging.” The articles published in the past 5-10 years were preferred. The contents of the articles mainly describe the principle of different tracking methods, and their application in animal models and patients. RESULTS AND CONCLUSION: In the past 20 years, cell tracking has developed into a multifarious discipline, not only establishing a variety of robust methods in animal models, but also proving the feasibility of clinical transformation in some human studies. The development of the non-invasive detection methods, such as PET and MRI, and new contrast agents provides strong support for the application of cell therapy in clinical and scientific researches.

18.
Article in Chinese | WPRIM | ID: wpr-942698

ABSTRACT

Fluorescence imaging now becomes an intraoperative navigation technique that gaining popularity in surgery and clinical research. However, at present, there is no mature and reliable method or other related guidance documents for the detection of fluorescence imaging performance. The performance analysis and quality supervision of products on the market could not be performed, which affects their clinical use and image quality. In this paper, a standard method of fluorescence imaging performance testing for fluorescence imaging system is proposed. Several kinds of fluorescence imaging performance parameters affecting fluorescence images are defined strictly. We also recommend scientific and feasible methods for their detections and analyses, which are verified by practical examples. This paper aims to provide a feasible reference standard for fluorescence performance evaluation.


Subject(s)
Diagnostic Imaging/instrumentation , Fluorescence
19.
Article in Chinese | WPRIM | ID: wpr-865666

ABSTRACT

Nitric oxide (NO) is a second messenger playing crucial roles in the signaling of a variety of cellular functions. Due to its pathophysiological significance, various NO modulators have been developed to explore NO pathways and some have been used as therapies. These modulators are often used directly to observe pharmacological effects in cell lines, but their actual effect on intracellular NO level is seldom analyzed. Herein, facilitated by a selective and sensitive fluorescence probe, we observed that some NO modulators displayed unexpected behaviors with both NO scavenger carboxy-PTIO and endothelial nitric oxide synthase (eNOS) inhibitor N(ω)-nitro-L-arginine methyl ester (L-NAME) failing to decrease intra-cellular free NO level in EA. hy926 cells while NO donor diethylamine-NONOate (DEA?NONOate) and eNOS activator calcimycin (A23187) failing to increase free NO level in human umbilical vein endothelial cell line (HUV-EC-C), although the reagents were confirmed to work normally in the primary human umbilical vein endothelial cells (primary HUVECs) and RAW 264.7 macrophage cells. Further research suggested that these unusual behaviors might be attributed to the cellular microenvironments including both the NO synthase (NOS) level and the endogenous glutathione (GSH) level. Genetically manipulating eNOS level in both cells restores the expected response, while decreasing GSH level restores the ability of DEA?NONOate to increase NO level in HUV-EC-C. These results reveal that the cellular microenvironment has a profound impact on pharmacological effect. Our study suggests GSH as a reservoir for NO in live cells and highlights the value of chemical probes as valuable tools to reveal microenvironment-dependent pharmacological effects.

20.
Article in Chinese | WPRIM | ID: wpr-865662

ABSTRACT

Fluorescence imaging can provide valuable information on the expression, distribution, and activity of drug target proteins. Chemical probes are useful small-molecule tools for fluorescence imaging with high structural flexibility and biocompatibility. In this review, we briefly introduce two classes of fluorescent probes for the visualization of drug target proteins. Enzymatically activatable probes make use of the specific enzymatic transformations that generally produce a fluorogenic response upon reacting with target enzymes. Alternatively, specific imaging can be conferred with a ligand that drives the probes to target proteins, where the labeling relies on noncovalent binding, covalent inhibition, or traceless la-beling by ligand-directed chemistry.

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