Encapsulation engineering of porous crystalline frameworks for delayed luminescence and circularly polarized luminescence.

Delayed luminescence (DF), including phosphorescence and thermally activated delayed fluorescence (TADF), and circularly polarized luminescence (CPL) exhibit common and broad application prospects in optoelectronic displays, biological imaging, and encryption. Thus, the combination of delayed luminescence and circularly polarized luminescence is attracting increasing attention. The encapsulation of guest emitters in various host matrices to form host-guest systems has been demonstrated to be an appealing strategy to further enhance and/or modulate their delayed luminescence and circularly polarized luminescence. Compared with conventional liquid crystals, polymers, and supramolecular matrices, porous crystalline frameworks (PCFs) including metal-organic frameworks (MOFs), covalent-organic frameworks (COFs), zeolites and hydrogen-bonded organic frameworks (HOFs) can not only overcome shortcomings such as flexibility and disorder but also achieve the ordered encapsulation of guests and long-term stability of chiral structures, providing new promising host platforms for the development of DF and CPL. In this review, we provide a comprehensive and critical summary of the recent progress in host-guest photochemistry via the encapsulation engineering of guest emitters in PCFs, particularly focusing on delayed luminescence and circularly polarized luminescence. Initially, the general principle of phosphorescence, TADF and CPL, the combination of DF and CPL, and energy transfer processes between host and guests are introduced. Subsequently, we comprehensively discuss the critical factors affecting the encapsulation engineering of guest emitters in PCFs, such as pore structures, the confinement effect, charge and energy transfer between the host and guest, conformational dynamics, and aggregation model of guest emitters. Thereafter, we summarize the effective methods for the preparation of host-guest systems, especially single-crystal-to-single-crystal (SC-SC) transformation and epitaxial growth, which are distinct from conventional methods based on amorphous materials. Then, the recent advancements in host-guest systems based on PCFs for delayed luminescence and circularly polarized luminescence are highlighted. Finally, we present our personal insights into the challenges and future opportunities in this promising field.

Exploration on ALT threshold for initiating antiviral therapy in chronic HBV-infected patients based on results of 707 liver puncture cases / 中国热带医学

@#Abstract: Objective To explore the threshold of ALT for initiating antiviral therapy in HBV infected patients, and to provide a basis for initiating antiviral therapy in chronic HBV-infected patients. Methods This retrospective cohort study recruited 707 consecutive treatment-naïve chronic hepatitis B (CHB) patients undergoing diagnostic liver biopsy in the department of infectious diseases of the Affiliated Hospital of Yan′an University from October 2013 to August 2018. Liver biopsy specimens were obtained under ultrasound guidance using Menghini 16G disposable needles. The METAVIR scoring system, which is commonly used internationally, was used to divide the patients into the group with mild liver tissue injury and the group with significant liver tissue injury, and the alanine aminotransferase (ALT) levels were measured separately. Receiver operating characteristic (ROC) curve and Mann-Whitney U test were used to evaluate the diagnostic value of ALT for significant liver tissue injury under different demographic characteristics. Results Of 707 patients, 292 (41.30%) had significant liver tissue injury confirmed by liver biopsy (METAVIR ≥A2 and/or F2). When the ULN of ALT was set to NICE criteria (30 U/L for males, 19 U/L for females), AASLD criteria (35 U/L for males, 25 U/L for females) and EASL or APASL criteria (40 U/L for males and females), CHB patients with <ULN accounted for 32.38%, 35.03% and 36.07% of significant liver tissue injury, respectively. And significant liver tissue injury in CHB patients with 1-2×ULN accounted for 41.99%, 41.85% and 50.30%, respectively. The optimal ALT critical values were 33 U/L for overall patients, 25 U/L for females, 45 U/L for males, 45 U/L for ≤30 years olds, 33 U/L for>30 years olds, 22 U/L for HBeAg negative and 31 U/L for HBeAg positive patients. Conclusions The threshold of ALT for initiating antiviral therapy in chronic HBV patients should be individualized, especially should be down-regulated for the females, olders and HBeAg-negative patients.

Multicolor-tunable room-temperature afterglow and circularly polarized luminescence in chirality-induced coordination assemblies.

Dynamic long-lived multicolor room temperature afterglow and circularly polarized luminescence (CPL) are promising for optoelectronic applications, but integration of these functions into a single-phase chiroptical material is still a difficult and meaningful challenge. Here, a nitrogen-doped benzimidazole molecule 1H-1,2,3-triazolopyridine (Trzpy) showing pure organic room-temperature phosphorescence (RTP) acted as a linker, and then, we propose a chirality-induced coordination assembly strategy to prepare homochiral crystal materials. Two homochiral coordination polymers DCF-10 and LCF-10 not only exhibit multicolor-tunable RTP, the color changed from green to orange under various excitation wavelengths, but also show remarkable excitation-dependent circularly polarized luminescence (CPL), and the dissymmetry factors of CPL in DCF-10 and LCF-10 are 1.8 × 10-3 and 2.4 × 10-3, respectively. Experimental and theoretical studies demonstrated that molecular atmospheres with different aggregation degrees give rise to multiple emission centers for the generation of multicolor-tunable emission. The multicolor-tunable photophysical properties endowed LCF-10 with a huge advantage for multi-level anti-counterfeiting. This work opens up new perspectives for the development and application of color-tunable RTP and CPL.

Iron Porphyrin as a Cytochrome P450 Model for the Degradation of Dye.

Organic dyes are widely used in the textile, biological, medical and other fields. However, a serious environmental problem has appeared because of the presence of organic dyes in industrial aqueous effluents. Thus, the efficient treatment of organic dyes in industrial wastewaters is currently in real demand. The current study investigated the oxidative degradation of the organic dye gentian violet by meso-tetra(carboxyphenyl) porphyriniron(III), [FeIII(TCPP)] as a cytochrome P450 model and iodosylbenzene (PhIO) as an oxidant at room temperature. The degradation reaction was monitored by UV-vis absorption spectroscopy via the observation of UV-vis spectral changes of the gentian violet. The results showed that the efficiency of catalyzed degradation reached more than 90% in 1 h, indicating the remarkable oxidative degradation capacity of the [FeIII(TCPP)]/PhIO system, which provided an efficient approach for the treatment of dyeing wastewater.

Determination of the species status of Fallopia multiflora, Fallopia multiflora var. angulata and Fallopia multiflora var. ciliinervis based on morphology, molecular phylogeny, and chemical analysis.

Relationships among Fallopia multiflora (Thunb.) Haraldson., F. multiflora var. angulata (S. Y. Liu) H. J. Yan, Z. J. Fang & Shi Xiao Yu., and F. multiflora var. ciliinervis (Nakai) Yonekura & H. Ohashi. were determined based on macroscopic and microscopic morphology, molecular phylogeny, and chemical analysis. The macroscopic and microscopic morphologies of root tubers or rhizomes, stems, and leaves were compared among the three taxa. The content of 11 chemical components (catechin, polydatin, stilbene glucoside, emodin, emodin-8-O-ß-D-glucopyranoside, rhein, chrysophanol, aloe-emodin, quercetin, physcion, and resveratrol) in the three taxa was determined by HPLC, and the chemical diversity was further evaluated by principal component and hierarchical cluster analyses. Molecular phylogenies were mapped using two chloroplast markers (matK and the psbA-trnH intergenic region) and a nuclear ribosomal marker [internal transcribed spacer 2 (ITS2) region]. Analyses of macroscopic and microscopic morphological characteristics revealed that the subterranean organs of F. multiflora and F. multiflora var. angulata are root tubers, whereas those of F. multiflora var. ciliinervis are rhizomes. In the phylogenetic trees, F. multiflora and F. multiflora var. angulata were clustered into a clade based on the combine matK + psbA-trnH sequence, with neighbour-joining, maximum likelihood, and Bayesian inference bootstrap support values of 99, 85, and 0.99, respectively. In addition, there were obvious differences in the chemical compositions of F. multiflora, F. multiflora var. angulata and F. multiflora var. ciliinervis. The root tubers of F. multiflora contain higher levels of stilbene glucoside and catechin, but lower levels of polydatin and anthraquinone compounds. In contrast to F. multiflora, the rhizomes of F. multiflora var. ciliinervis contain higher levels of polydatin and anthraquinone compounds, but lack stilbene glucoside. The content of all 11 assessed components was lower in F. multiflora var. angulata than in F. multiflora and F. multiflora var. cillinervis. Principal component and hierarchical cluster analyses revealed that F. multiflora and F. multiflora var. angulata individuals were clustered into a single clade, whereas F. multiflora var. ciliinervis individuals were clustered into a single clade separate from that containing F. multiflora and F. multiflora var. angulata individuals. On the basis of the results of our morphological, molecular phylogeny, and chemical analyses, we tentatively conclude that F. multiflora var. ciliinervis is an independent species, whereas F. multiflora var. angulata should be considered as a variety of F. multiflora.

Photoresponse Enhancement in Monolayer ReS2 Phototransistor Decorated with CdSe-CdS-ZnS Quantum Dots.

ReS2 films are considered as a promising candidate for optoelectronic applications due to their direct band gap character and optical/electrical anisotropy. However, the direct band gap in a narrow spectrum and the low absorption of atomically thin flakes weaken the prospect for light-harvesting applications. Here, we developed an efficient approach to enhance the performance of a ReS2-based phototransistor by coupling CdSe-CdS-ZnS core-shell quantum dots. Under 589 nm laser irradiation, the responsivity of the ReS2 phototransistor decorated with quantum dots could be enhanced by more than 25 times (up to ∼654 A/W) and the rising and recovery time can be also reduced to 3.2 and 2.8 s, respectively. The excellent optoelectronic performance is originated from the coupling effect of quantum dots light absorber and cross-linker ligands 1,2-ethanedithiol. Photoexcited electron-hole pairs in quantum dots can separate and transfer efficiently due to the type-II band alignment and charge exchange process at the interface. Our work shows that the simple hybrid zero- and two-dimensional hybrid system can be employed for photodetection applications.

Chemical Vapor Deposition Growth of Degenerate p-Type Mo-Doped ReS2 Films and Their Homojunction.

Substitutional doping of transition metal dichalcogenide two-dimensional materials has proven to be effective in tuning their intrinsic properties, such as band gap, transport characteristics, and magnetism. In this study, we realized substitutional doping of monolayer rhenium disulfide (ReS2) with Mo via chemical vapor deposition. Scanning transmission electron microscopy demonstrated that Mo atoms are successfully doped into ReS2 by substitutionally replacing Re atoms in the lattice. Electrical measurements revealed the degenerate p-type semiconductor behavior of Mo-doped ReS2 field effect transistors, in agreement with density functional theory calculations. The p-n diode device based on a doped ReS2 and ReS2 homojunction exhibited gate-tunable current rectification behaviors, and the maximum rectification ratio could reach up to 150 at Vd = -2/+2 V. The successful synthesis of p-type ReS2 in this study could largely promote its application in novel electronic and optoelectronic devices.

Early intervention with Didang decoction delays macrovascular lesions in diabetic rats through regulating AMP-activated protein kinase signaling pathway.

The study aimed to investigate the intervening role of Didang decoction (DDD) at different times in macrovascular endothelial defense function, focusing on its effects on the AMP-activated protein kinase (AMPK) signaling pathway. The effects of DDD on mitochondrial energy metabolism were also investigated in rat aortic endothelial cells (RAECs). Type 2 diabetes were induced in rats by streptozotocin (STZ) combined with high fat diet. Rats were randomly divided into non-intervention group, metformin group, simvastatin group, and early-, middle-, late-stage DDD groups. Normal rats were used as control. All the rats received 12 weeks of intervention or control treatment. Western blots were used to detect the expression of AMP-activated protein kinase α1 (AMPKα1) and peroxisome proliferator-activated receptor 1α (PGC-1α). Changes in the intracellular AMP and ATP levels were detected with ELISA. Real-time-PCR was used to detect the mRNA level of caspase-3, endothelial nitric oxide synthase (eNOS), and Bcl-2. Compared to the diabetic non-intervention group, a significant increase in the expression of AMPKα1 and PGC-1α were observed in the early-stage, middle-stage DDD groups and simvastatin group (P < 0.05). The levels of Bcl-2, eNOS, and ATP were significantly increased (P < 0.05), while the level of AMP and caspase-3 were decreased (P < 0.05) in the early-stage DDD group and simvastatin group. Early intervention with DDD enhances mitochondrial energy metabolism by regulating the AMPK signaling pathway and therefore may play a role in strengthening the defense function of large vascular endothelial cells and postpone the development of macrovascular diseases in diabetes.

Morphological study on apoptosis Hela cells induced by soyasaponins.

Soyasaponins are present in legumes and soybeans are the primary dietary source of saponins. SS-II, the second fraction of soyasaponins, was separated by column chromatographic method with D101A macroporous resin from soybean. In this paper, at the concentration range of 100-400 mg/L, SS-II had obvious cytotoxic effect on Hela cells by MTT assay. After Hela cells were treated with SS-II, typical apoptotic morphological changes, including nuclear fragmentation, cytoplasm shrinkage and decrease of cell volume, were observed by fluorescence microscope, transmission electron microscope (TEM) and confocal laser scanning microscope (CLSM), respectively. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay also confirmed that SS-II-treated Hela cells showed apoptotic features. The results suggested that soyasaponins were a potential antitumor compound and the apoptosis induced by soyasaponins was a key antitumor mechanism.

[Effects of carotenoids extracts from Potamogeton crispus on apoptosis of human hepatoma cell line QGY-7703 in vitro].

Human hepatoma cell line QGY-7703 was treated with the medium containing 10, 20, 40 and 60 micromol/L carotenoids extracts from Potamogoton crispus L. (CEPC) for 48 h, 96 h and 144 h, respectively. The inhibition rates to hepatoma cells were determined by MTT assay. The results showed the average inhibition rates of the three treatments varied from 0.14%-23.07%, 39.59%-70.61% and 71.65%-87.01%, respectively. After hepatoma cells were treated with the medium containing 10, 20 and 40 micromol/L of CEPC for 24 h, 48 h and 72 h, respectively, many typical morphology features of apoptotic cells were observed by Laser Scanning Confocal Microscope (LSCM), such as the distinct decrease in number and volume of cells, the shrinkage and deformation of cells, the shape of cell nucleuses appearing like crescent even piece, the decrease in area of yellow DNA in cell nuclei. The percentage of hepatoma cells in every phase of cell cycle was analyzed by Flow Cytometer (FCM) after being treated with 10 micromol/L and 20 micromol/L CEPC for 48 h. Compared with the control group, the cells in G0/G1 phase increased 23.8% (P<0.01) and 35.6% (P<0.01) respectively, in S phase decreased relevantly, while the cells in G2/M phase had no significant change. The Ca2+ concentration (fluorescence intensity) in cytoplasm of hepatoma cells was determined by LSCM after being treated with 20 micromol/L CEPC for 48 h. The Ca2+ concentration increased significantly (P<0.01) and was 1.5 times that of control group. These results demonstrated that the CEPC inhibited the proliferation of hepatoma cells QGY-7703 significantly in a dose and time-dependent manner in vitro. The hepatoma cells treated with CEPC were evidently arrested at G0/G1 phase in the cell cycle. The concentration of Ca2+ in test group cells cytoplasm increased significantly, it might be the important cause that CEPC induced the apoptosis of hepatoma cells QGY-7703. This paper provided scientific basis for further studying and developing the function and value of carotenoids in Potamogoton crispus L.