Applications of smartphone-based near-infrared (NIR) imaging, measurement, and spectroscopy technologies to point-of-care (POC) diagnostics / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

The role of point-of-care (POC) diagnostics is important in public health. With the support of smartphones, POC diagnostic technologies can be greatly improved. This opportunity has arisen from not only the large number and fast spread of cell-phones across the world but also their improved imaging/diagnostic functions. As a tool, the smartphone is regarded as part of a compact, portable, and low-cost system for real-time POC, even in areas with few resources. By combining near-infrared (NIR) imaging, measurement, and spectroscopy techniques, pathogens can be detected with high sensitivity. The whole process is rapid, accurate, and low-cost, and will set the future trend for POC diagnostics. In this review, the development of smartphone-based NIR fluorescent imaging technology was described, and the quality and potential of POC applications were discussed.

Fluorescent antibiotics for real-time tracking of pathogenic bacteria / 药物分析学报

The harm of pathogenic bacteria to humans has promoted extensive research on physiological processes of pathogens, such as the mechanism of bacterial infection, antibiotic mode of action, and bacterial antimicrobial resistance. Most of these processes can be better investigated by timely tracking of fluorophore-derived antibiotics in living cells. In this paper, we will review the recent development of fluorescent antibiotics featuring the conjugation with various fluorophores, and focus on their applica-tions in fluorescent imaging and real-time detection for various physiological processes of bacteria in vivo.

Application of indocyanine green labeled near-infrared fluorescence laparoscopy in gastric cancer / 中华肿瘤杂志

Objective@#With the development of laparoscopic surgery technique, the concept of minimally invasive surgery has gradually gained popularity. Laparoscopic minimally invasive technique applied in the treatment of gastric cancer has been recognized by surgeons. In recent years, the indocyanine green labeled near-infrared fluorescence laparoscopic technique has been gradually applied to the surgical treatment of gastric cancer. This technique overcomes the drawbacks of tactile lack of laparoscopic surgery and makes the laparoscopic surgery of gastric cancer more precise and minimally invasive. This article introduces the injection method of indocyanine green and discusses the application of fluorescent laparoscopy in gastric cancer surgery, including intraoperative tumor localization of early gastric cancer, sentinel lymph node biopsy, lymph node navigation of advanced gastric cancer, digestive tract reconstruction and gastrointestinal blood perfusion assessment during the procedure.

Preclinical application of MR and fluorescent dual-modality imaging combined with photothermal therapy in HER-2 positive breast cancer / 中华肿瘤杂志

Objective@#To construct superparamagnetic iron oxide nanoparticles (SPIONs) coated on trastuzumab and indocyanine green (ICG) and then investigate whether the coated nanoparticles (NPs) targeted to human epidermal growth factor receptor-2 (HER-2) receptors on breast cancer cells in vitro and in vivo.@*Methods@#The Fe3O4-trastuzumab-ICG NPs were constructed. And a series of characteristics of the NPs were evaluated. The uptake ability of SK-BR-3, a HER-2 positive breast cancer cell, was observed by transmission electron microscopy. Then the NPs were injected in the tail veins of SK-BR-3 xenograft tumor-bearing mice to observe the aggregation of NPs in the tumor sites by MRI and fluorescent imaging. Furthermore, when the NPs was gathered at the tumor sites, the near infrared thermal imaging system was used to monitor the tumor temperature after the near infrared radiation.@*Results@#The successfully constructed Fe3O4-trastuzumab-ICG NPs had the size of (25.93±4.25) nm. The absorption peak was 828 nm, which was as same as the emission wavelength of ICG. The NPs had a high relaxation rate of approximately 107.65 mM-1·s-1. The maximum temperature of NPs solution could reach to 57.8℃ after continuous near infrared laser irradiation. The transmission electron microscopy imaging revealed that the NPs could target and enter into the endoplasmic reticulum of SK-BR-3 cells. MRI analysis showed the lowest T2 relaxation time in the tumor sites 24 h after tail vein injection of the NPs. The △T2 of the tumor sites in the Fe3O4-trastuzumab-ICG group (30.7±4.8) ms was higher compared with that of control group (3.1±1.1) ms, Fe3O4-IgG-ICG group (4.4±0.9) ms and trastuzumab + Fe3O4-trastuzumab-ICG group (11.3±3.8) ms., respectively, all showing statistically significant differences (P<0.05). The fluorescence imaging revealed that the NPs was concentrated transiently in the intraperitoneal organs and tumor sites, then excreted into the bladder. After 24 h, there was an obvious aggregation in the tumor sites. The near infrared thermal imaging experiments showed that the temperature of tumor sites in Fe3O4-trastuzumab-ICG group could go up to 49.4℃ after continuous near infrared light irradiation.@*Conclusion@#The newly constructed Fe3O4-trastuzumab-ICG NPs have the potential to act as a multifunctional imaging agent and a powerful tool for photothermal therapy for HER-2 positive breast cancer.

Near-infrared imaging combined with intraoperative ultrasound in laparoscopic liver tumor resection / 中华普通外科杂志

Objective To evaluate intraoperative ultrasound combined with near-infrared imaging in laparoscopic liver tumor resection.Methods 15 cases undergoing laparoscopic hepatectomy at our department from Ju12017 to Sep 2017 were enrolled in this study.We observed the volume of resected liver,ICG test,the ability of detected lesion overlooked by preoperative imaging,operation time,blood loss,hospital stay,postoperative complication,final pathological result,and tumor margin.Results We have done laparoscopic hepatectomy in 15 cases by intraoperative ultrasound and near-infrared imaging.There was no conversion to open surgery,blood loss was (220 ± 159) rnl,operation time was (136 ±6) min,hospital stay was (8.6 ± 2.1) d,tumor margin was (1.6 ± 1.1) cm,all were tumor negative.There was no major complications such as postoperative bleeding,nor perioperative death.There were pleuraleffusion in 3 cases and bile leakage in one,all were cured by drainage.Conclusion Intraoperative ultrasound combined with near-infrared imaging during the process of laparoscopic hepatectomy helps in assuring safe tumor margin and preserving normal liver parenchyma.

Exploration of establishing a metastatic nude mouse model of double-tagging papillary thyroid cancer / 中华内分泌代谢杂志

Objective To obtain a thyroid cancer cell line integrated with luciferase and fluorescence,and to establish a metastatic nude mouse model of papillary thyroid cancer monitored with in vivo imaging system. Methods Lentivirus carrying recombinant plasmid containing luciferase gene and mCherry gene infected high malignant papillary thyroid cancer cell line (BHP10-3SCmice). The stable thyroid cancer cell line (BHP10-3mluc) labeled with luciferase and mCherry selected by hygromycin, analyzed for fluorescence with fluorescence microscopy and bioluminescence with in vitro analysis and in vivo imaging. 0.25 ml(5×106/ml)BHP10-3mluc cell suspension were injected into the left thigh intramuscular tissue of 5-week-old nude mice to establish BALB/C nude mice metastatic tumor model. The growth and metastasis of the tumors were monitored weekly with in vivo imaging system. The nude mice were sacrificed on the 42th day and the tissues with metastatic tumors were analyzed by fluorescent imaging ex vivo. The ectopic implanted tumors and metastatic lesions were verified by tissue sections with Hematoxylin and Eosin staining. Results BHP10-3mluc cells showed similar growth characteristics to the original BHP10-3SCmice cells and stably expressed luciferase and mCherry. At the end of the first week after ectopic implantation,the xenograft tumors were found and in the 6th week,the tumors were found to metastasized to adjacent lymph nodes and lungs,which was consistent with the results of pathology.The growth and metastasis of tumors can be accurately monitored with in vivo imaging system. Conclusions A PTC cell line stably expressing bioluciferase and fluorescence was successfully established.The nude mouse model of PTC metastatic tumor generated by intramuscular inoculation of those cells can be well monitored with in vivo imaging system, which provides ideal models for researches on tumor growth, metastasis,and drug treatment.

MR-fluorescent dual-modality molecular probes anchored with LyP-1 for pancreatic cancer / 中国医学影像技术

Objective To construct the LyP-1 targeted MR fluorescence dual-modality molecular probe for pancreatic cancer,and to observe its features and MRI charicteristics.Methods The 50 nm MR-fluorescent dual-modality molecular probe with surface modified with cyclic nine-amino acid peptide LyP-1 (Cys-Gly-Asn-Lys-Arg-Thr-Arg-Gly Cys) was rationally designed.Whether the molecular probe could specifically recognize the pancreatic cancer cells were validated by the combination of fluorescent imaging and MR T2WI.Results The new MR-fluorescent dual-modality molecular probe anchored with LyP-1 could be used for the fluorescent imaging and MR T2WI of pancreatic cancer in mouse.And the molecular probe was demonstrated to be effective in conjugating with pancreatic cancer cells on fluorescent images and caused obvious MR signal reduction under T2 relaxometry in vitro.In vivo experiment,the molecular probe could be used for fluorescent labeling tumor tissue and detecting orthotopic pancreatic cancer in C57BL/6 mouse as MR contrast agent.Conclusion The LyP1 immobilized MR-fluorescent dual-modality molecular probe can actively target to mouse orthotopic xenograft of pancreatic cancer,which is hopeful to the application in early probing and diagnosis of pancreatic cancer by multimodal imaging.

MR-fluorescent dual-modality molecular probes anchored with LyP-1 for pancreatic cancer / 中国医学影像技术

Objective To construct the LyP-1 targeted MR fluorescence dual-modality molecular probe for pancreatic cancer,and to observe its features and MRI charicteristics.Methods The 50 nm MR-fluorescent dual-modality molecular probe with surface modified with cyclic nine-amino acid peptide LyP-1 (Cys-Gly-Asn-Lys-Arg-Thr-Arg-Gly Cys) was rationally designed.Whether the molecular probe could specifically recognize the pancreatic cancer cells were validated by the combination of fluorescent imaging and MR T2WI.Results The new MR-fluorescent dual-modality molecular probe anchored with LyP-1 could be used for the fluorescent imaging and MR T2WI of pancreatic cancer in mouse.And the molecular probe was demonstrated to be effective in conjugating with pancreatic cancer cells on fluorescent images and caused obvious MR signal reduction under T2 relaxometry in vitro.In vivo experiment,the molecular probe could be used for fluorescent labeling tumor tissue and detecting orthotopic pancreatic cancer in C57BL/6 mouse as MR contrast agent.Conclusion The LyP1 immobilized MR-fluorescent dual-modality molecular probe can actively target to mouse orthotopic xenograft of pancreatic cancer,which is hopeful to the application in early probing and diagnosis of pancreatic cancer by multimodal imaging.

Based on in vivo fluorescence imaging technology, to extablish a fluorescence modification method for amphipathic block polymers / 药学学报

Rhodamine B (RhB) was used to decorate an amphipathic block polymers (β-CD-[P(AA-co-MMA)-b-PVP]4) in this study. First, after activated by 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride, rhodamine B was marked with hydroxyethyl methacrylate (HEMA) through ester exchange reaction. Second, the labeled amphipathic block polymers (β-CD-[P(AA-(HEMA-RhB)-MMA)-b-PVP]4) were synthesized after polymerization reaction of double bones between RhB-HEMA and other reactants. Finally, the structure of product was measured by FT-IR spectra and fluorospectro photometer (FLUORO). The critical micelle concentration of RhB-labeled and unlabeled amphipathic block polymers were 4.96×10-3, 5.09×10-3 mg·L-1, respectively, indicating no change of their micellization behavior. In vivo tissue distribution and whole-body fluorescent imaging were studied by vinpocetine (VP)-loaded polymeric micelles which were prepared through a solvent evaporation method. Compared to the result of in vivo tissue distribution and whole-body fluorescence imaging, a similar bio-distribution behavior of VP-loaded polymeric micelles was found. Those proved the successful fluorescence modification with a labeling yield of 4.13%. With in vivo fluorescence imaging technology, we established a fluorescence method for modification of amphipathic block polymers.

A Rapid and Convenient Method for in Vivo Fluorescent Imaging of Protoscolices of Echinococcus multilocularis

Human and animal alveolar echinococcosis (AE) are important helminth infections endemic in wide areas of the Northern hemisphere. Monitoring Echinococcus multilocularis viability and spread using real-time fluorescent imaging in vivo provides a fast method to evaluate the load of parasite. Here, we generated a kind of fluorescent protoscolices in vivo imaging model and utilized this model to assess the activity against E. multilocularis protoscolices of metformin (Met). Results indicated that JC-1 tagged E. multilocularis can be reliably and confidently used to monitor protoscolices in vitro and in vivo. The availability of this transient in vivo fluorescent imaging of E. multilocularis protoscolices constitutes an important step toward the long term bio-imaging research of the AE-infected mouse models. In addition, this will be of great interest for further research on infection strategies and development of drugs and vaccines against E. multilocularis and other cestodes.

Construction of In Vivo Fluorescent Imaging of Echinococcus granulosus in a Mouse Model

Human hydatid disease (cystic echinococcosis, CE) is a chronic parasitic infection caused by the larval stage of the cestode Echinococcus granulosus. As the disease mainly affects the liver, approximately 70% of all identified CE cases are detected in this organ. Optical molecular imaging (OMI), a noninvasive imaging technique, has never been used in vivo with the specific molecular markers of CE. Thus, we aimed to construct an in vivo fluorescent imaging mouse model of CE to locate and quantify the presence of the parasites within the liver noninvasively. Drug-treated protoscolices were monitored after marking by JC-1 dye in in vitro and in vivo studies. This work describes for the first time the successful construction of an in vivo model of E. granulosus in a small living experimental animal to achieve dynamic monitoring and observation of multiple time points of the infection course. Using this model, we quantified and analyzed labeled protoscolices based on the intensities of their red and green fluorescence. Interestingly, the ratio of red to green fluorescence intensity not only revealed the location of protoscolices but also determined the viability of the parasites in vivo and in vivo tests. The noninvasive imaging model proposed in this work will be further studied for long-term detection and observation and may potentially be widely utilized in susceptibility testing and therapeutic effect evaluation.

Molecular Optical Imaging in Neuroscience

Molecular imaging is leading an important role in the era of molecular medicine. Optical imaging, a rising star in the filed of molecular imaging, largely consists of bioluminescent imaging and fluorescent imaging. It has been shown that well-aimed and creatively-built optical-imaging-reporters let researchers explore and answer a lot of biologically important questions in living subjects. Despite relatively short history, molecular optical imaging is rapidly being implemented not only in many clinical areas but also in various research fields from tracking gene expression, protein-protein interaction or migrating cells to molecular diagnosis and treatment.

Optical Imaging in the Field of Molecular Imaging

Molecular imaging is leading an important role in the era of molecular medicine. Optical imaging, a rising star in the filed of molecular imaging, largely consists of fluorescent imaging and bioluminescent imaging. In the fluorescence imaging, an illuminating light excites fluorescent reporters in the living subject, and a charged coupled device (CCD) camera collects an emission light of shifted wavelength. In the bioluminescent imaging, reporter genes code for the luciferase that is responsible for fireflies' glow. After the injection of the substrate iuciferin, animals carrying the luciferase gene are imaged with a supersensitive CCD camera to pick up the small number of photons transmitted through tissues. It has been shown that well aimed and creatively built reporters let researchers explore and answer a lot of biologically important questions in living subjects. Despite its relatively short history, optical imaging is rapidly being implemented in various clinical areas as well as research fields.