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Multimodality therapy based on surgery is the main treatment method for hepatocellular carcinoma（HCC）, and hepatectomy requires the removal of primary tumor and the preservation of normal liver tissue to the maximum extent. However in clinical surgery, it is difficult to accurately identify tumor tissue and its boundary with visual inspection and palpation, which often results in under-resection or over-resection. Near-infrared fluorescence（NIRF） imaging is a real-time noninvasive imaging technique with low costs and high sensitivity, and extensive studies have been conducted to investigate its application in guiding surgical resection of tumors. With the development of fluorescence imaging system and fluorescence probe, intraoperative tumor localization and boundary determination can be realized to make the surgery more accurate. This article reviews the development of various NIRF probes for intraoperative navigation in HCC and discusses current challenges and potential opportunities of these imaging probes. [ABSTRACT FROM AUTHOR]

Objective To study the interactions between α-synuclein and the effective components（puerarin，chrysophanol，ursodesoxycholic acid） of Anshenxingnao traditional Chinese medicines and to investigate the junction state of medications with α-synuclein. Methods The interactions between α-synuclein and the effective components of Anshenxingnao traditional Chinese medicines was studied by using the fluorescence titrimetric method. The fluorescence data were analyzed by using the Scatchard equation for obtaining the dissociation canstant KD of α-synuclein-drug complexes. Results After adding puerarin，chrysophanol and ursodeoxycholic acid respectively，the fluorescent strength of α-synuclein was gradually reduced and the emission peak location had no shift. On the contrary，the fluorescence strengthes of puerarin，chrysophanol and ursodeoxycholic acid were gradually enhanced after adding the α-synuclein. The KD values of puerarin，chrysophanol，ursodeoxycholic acid and α-synuclein by protein fluorescence data were 0.368 5×10-5 ，2.778 2×10-5 ，0.317 2×10-5 mol/L respectively. The KD values obtained by drug fluorescence data were basically consistent with them. Conclusion The binding action respectively exists between puerarin，chrysophanol and ursodesoxycholic acid with α-synuclein，thus which quenches the fluorescence of α-synuclein，in which the binding action between ursodeoxycholic acid and α-synuclein is stronger. [ABSTRACT FROM AUTHOR]

Objective: To establish a model for screening Mycobacterium tuberculosis (M. tuberculosis) proteasome inhibitors in vitro., Methods: The proteasome inhibitor in vitro screening model was established according to the principle that the fluorescent substrate Suc-Leu-Leu-Val-AMC (S-LLVY-AMC) was hydrolyzed by the proteasome and released AMC (7-amino-4-methylcoumarin) which was fluorescent, and the fluorescence value was proportional to the proteasome activity. Conditions which could affect proteasome activity including the time of the reaction, concentration of proteasome, or SDS, were evaluated. The model was validated by using the known proteasome inhibitor MG132 and 8 natural products. Linear correlation and regression analysis were performed by the factors affecting fluorescence values., Results: In the model for screening M. tuberculosis proteasome inhibitors in vitro, the reaction system consisted of 0.34 mg/L SDS, 25 mg/L protein and 64 µmol/L S-LLVT-AMC, and the reaction time was 30 min. By using MG132 and natural compounds A-H to validate the MTB proteasome screening model, the calculated IC50 of MG132 was 49 µmol/L. In a final concentration of 200 µmol/L, the inhibition rates of 8 drugs on MTB proteasome were 0.0%, 3.1%, 7.8%, 45.2%, 52.4%, 69.5%, 69.6%, 88.7% respectively, confirming that the model was repeatable and reliable., Conclusions: In this study, we established a model for screening M. tuberculosis proteasome inhibitors in vitro, which could provide a technical platform for fast and large scale screening of mycobacterial proteasome inhibitors.

Aim: To establish a fluorospectrophotometric assay for the measurement of nitrite in blood., Methods: Interference from hemoglobin and other blood ingredients was removed through sulfuric acid and phosphotungstic acid pretreatment. Fluorescence of 1-[H]-naphthotriazole from the reaction of 2,3-diaminonaphthalene with nitrite was determined with fluorospectrophotometry., Results: The following conditions were proper: Serum or plasma was treated with sulfuric acid and phosphotungstic acid pretreatment for two times, 2,3-diaminonaphthalene of 0.63 mmol x (L(-1)) was used, reaction solution pH and final pH were about 1.60 and 1.70 respectively, solution containing 2,3-diaminonaphthalene and supernatant after pretreatment was water-bathed at 20 degrees C for 15 minutes. The lower limit of detection was 24.27 nmol x L(-1). Nitrite determined in peripheral blood of healthy people was (10.91 +/- 2.38) micromol x L(-1), and its 95% distribution range was (6.24-15.57) micromol x L(-1)., Conclusion: It's a relatively sensitive, specific, simple method. It's of some value to the study of nitric oxide.

Objective: The contents and dissolution rates of As, Hg, Cd and Pb including 44 batches of Astragali samples from major habitats were analysed., Method: As was determined by hydride generation-AFS. Hg was determined by cold vapour-ASS. Cd and Pb were determined by ICP-ES., Results: The contents of As, Hg, Cd, Pb were 0.018-0.617 microgram/g, 0.004-0.181 microgram/g, 0.029-0.168 microgram/g, and 0.290-5.501 micrograms/g respectively. The As, Hg, Cd, Pb dissolution rates were 30.2%-54.2%, 4.9%-9.8%, 50.%-87.9%, and 12.6%-27.8% respectively., Conclusion: The contents of As, Hg and Cd were very low and below the limitation of national food and hygiene standard, but that of Pb was high in Astragali and its extracts.

Different methods were used to detect minimal residual leukemic cells (LT 12 nl), which had been genetically marked with E. coli 1 acZ and neo-gene by retrovirus vector mediated gene transfer. The detection levels of flow cytometry based FDG staining and fluorophotometric method based MUG staining were 10(-3) to 10(-4) and 10(-2) to 10(-3), respectively. The method of G 418 selective agar culture was demonstrated as a 10(-4) to 10(-5) levels for the detection of LT 12 nl residual leukemic cells in bone marrow. The results indicated that the selective agar culture can be used as a sensitive method for the study of minimum residual disease in the BNML leukemia model. We have used the selective agar culture to study the distribution of clonal LT 12 nl cells in BNML during minimum residual disease (MRD). A heterogenous distribution pattern of the clonal leukemic cells was found in the genetically marked BNML leukemia model during the MRD phase.