AIEE-active dichlorobenzene and chlorobenzene ratiometric fluorescent probe based on [2.2]paracyclophane.

Two AIEE-active [2.2]paracyclophanyl-based diester and monoester (1a and 1b) were facilely synthesized by one-pot method and applied as ratiometric fluorescent probe to detect dichlorobenzene (DCB) and chlorobenzene (CB). Compared with compound 1b, 1a exhibits high sensitivity and low detection limits for DCB and CB in dichloromethane (DCM), particularly, the detection sensitivities for ortho-dichlorobenzene (o-DCB), meta-dichlorobenzene (m-DCB) and chlorobenzene can be modulated by AIEE behavior with lower detection limits of 23.64, 56.27, and 5.92 ppm, respectively in THF/H2O mixed solutions with water fraction (fw) of 70 % due to the formation of aggregation-state. The X-ray structure analysis, theoretical calculations and photophysical properties in different solvents were investigated to reveal the distinctive photophysical behaviors of 1a and 1b. The facile synthesis, X-ray structure, AIEE modulated sensing properties for o-DCB, m-DCB, and CB in DCM and THF/H2O mixed solutions make 1a potential application as fluorescent probe for trace DCB and CB detection in drinking water.

A synthetic peptide AWRK6 ameliorates metabolic associated fatty liver disease: involvement of lipid and glucose homeostasis.

Metabolic associated fatty liver disease (MAFLD) is the leading common chronic liver disease affecting more than one-quarter of the population worldwide, but no pharmacological therapy was approved specifically. A synthetic peptide AWRK6 developed in our group based on the antimicrobial peptide Dybowskin-2CDYa was found to attenuated diabetes as a novel GLP-1 receptor agonist candidate. The effects of AWRK6 on MAFLD and its underlying mechanisms were investigated in this paper. In high energy diet (HED)-induced MAFLD mice, obesity and hepatic steatosis were alleviated by AWRK6 via intraperitoneal injection. The biochemistry measurements data indicated that the abnormal lipid metabolism was relieved and the glucose metabolism was improved significantly. Further, the phosphorylation of liver PI3K/AKT/AMPK/ACC was elevated significantly by AWRK6 treatment. Moreover, the effects of AWRK6 on lipid accumulation and insulin sensitivity in human cells were verified using oleic acid-induced HepG2 fatty liver cell model and insulin-induced HepG2 cells, respectively. These in vitro and in vivo results demonstrated that the peptide AWRK6 ameliorates MAFLD by improving lipid and glucose metabolism homeostasis, and it is mediated by the PI3K/AKT/AMPK/ACC signaling pathway. Thus, AWRK6 has a potential in preventing MAFLD.

New hydrophilic/lipophilic tetra-α-(4-carboxyphenoxy) phthalocyanine zinc-mediated photodynamic therapy inhibits the proliferation of human hepatocellular carcinoma Bel-7402 cells by triggering apoptosis and arresting cell cycle.

Photodynamic therapy (PDT) is a novel and promising antitumor treatment. Phthalocyanine-mediated PDT has shown antitumor activity in some tumor cells, but the effect of new hydrophilic/lipophilic tetra-α-(4-carboxyphenoxy)phthalocyanine zinc (TαPcZn)-mediated PDT (TαPcZn-PDT) on human hepatocellular carcinoma Bel-7402 cells and underlying mechanisms have not been clarified. In the present study, therefore, the ultraviolet-visible (UV-vis) absorption spectrum and cellular localization of TαPcZn, and effect of TαPcZn-PDT on the proliferation, apoptosis, cell cycle, Bcl-2 and Fas in Bel-7402 cells were investigated by spectrophotometry, inverted microscope, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) assay, electron microscopy, annexinV-FITC/propidium iodide double staining, DNA content and immunoblot assay, respectively. We found that an intense absorption in UV-vis absorption spectrum of TαPcZn was in the red visible region at 650-680 nm, where light penetration in tissue is efficient, that green TαPcZn localized to both plasma membrane and nuclear membrane of Bel-7402 cells, signifying that there was a selective uptake of TαPcZn in Bel-7402 cells and TαPcZn-PDT would be expected to directly damage DNA, and that TαPcZn-PDT significantly resulted in the proliferation inhibition, apoptosis induction, S cell cycle arrest, and down-regulation of Bcl-2 and Fas. Taken together, we conclude that TαPcZn-PDT inhibits the proliferation of Bel-7402 cells by triggering apoptosis and arresting the cell cycle.

Optimization of intravascular brachytherapy treatment planning in peripheral arteries.

This work deals with the treatment planning optimization for intravascular brachytherapy (IVB) in peripheral arteries. The objective is both to quantitatively study the validity of different hypotheses required for a reliable application of the treatment with current techniques, and to contribute to the definition and the specification of a new optimized procedure taking into account the actual patient's vessel geometry. The detection of vascular luminal surface was performed by an image analysis process, i.e., virtual active navigation, applied to standard CT data. Dose distribution was calculated according to the formalism proposed and recommended by the AAPM in TG43 and TG60. A method combining simulated annealing and BFGS algorithms was applied to optimize the parameters associated with the dwell points such as their number, positions, and dwell times. Dose-surface histogram (DSH) was used to evaluate the dose distribution results. Four levels of accuracy in target surface description were tested. The application of this optimization method to four different CT data sets including patient data, phantom and animal models showed that the treatment plan can be improved when the actual vessel geometry has been taken into account.

[Development of a three-dimensional precise conformal radiotherapy treatment planning system based on a cobalt-60 teletherapy unit].

In this paper, a three-dimensional precise conformal radiotherapy treatment planning system based on a cobalt-60 teletherapy unit is introduced. With the help of additional precise target localization and conformal field-shaping devices, the TPS can greatly improve the performance of conventional cobalt-60 teletherapy units in precise target localization, radiotherapy planning and dose delivery. The clinical practices show that the TPS has advantages of reliable precision and an affordable price , and it is urgently needed in our country.

A study of intravascular brachytherapy treatment planning in peripheral arteries.

A two-step method to determine the seed parameters for the planning of peripheral intravascular brachytherapy, which took the actual vessel geometry into consideration, was developed. Firstly, the characteristics of the vessel geometry was obtained by using active navigation; Then a method combined genetic algorithm with BFGS algorithm was applied to optimize the number of seeds, and the parameters associated with each seed such as the position, and the dwell time. Application of the method to a phantom model and three animal models of stenosis shows that promising result could be obtained, and the planning of peripheral intravascular brachytherapy should take actual vessel geometry into consideration.

[DICOM in radiotherapy].

Digital Image Communication in Medicine (DICOM) defines a standard method to store and transmit digital medical image information, in which there is a piece of implemented protocol named DICOM-RT that specially addresses both the transmission of radiation therapy image data and the ancillary data. In this paper, we firstly introduce the DICOM-RT with the emphases on its components, relationship with radiotherapy and how to produce the DICOM-RT object that refer to some certain radiotherapy information. Then we expatiate on the impact that benefits from applying DICOM-RT to radiotherapy, with an aid to accelerate its application in China.