Surficial Host-Guest Responsive CsPbBr3 Perovskite Nanocrystals for Programmable Multi-Level Information Encryption.

The design of smart stimuli-responsive photoluminescent materials capable of multi-level encryption and complex information storage is highly sought after in the current information era. Here, a novel adamantyl-capped CsPbBr3 (AD-CsPbBr3) perovskite NCs, along with its supramolecular host-guest assembly partner a modified ß-CD (mCD), mCD@AD-CsPbBr3, are designed and prepared. By dispersing these two materials in different solvents, namely, AD-CsPbBr3 in toluene, mCD@AD-CsPbBr3 in toluene, and mCD@AD-CsPbBr3 in methanol, the three solutions exhibit diverse photoluminescence (PL) turn-on/off or PL discoloration response upon supramolecular stimulus. Based on these responses, a proof-of-principle programmable Multi-Level Photoluminescence Encoding System (MPLES) is established. Three types of four-level and three types of three-level information encoding are achieved by the system. A layer-by-layer four-level information encryption and decryption as well as a two-level encrypted 3D code are successfully achieved.

18F-fluoromisonidazole positron emission tomography may be applicable in the evaluation of colorectal cancer liver metastasis.

BACKGROUND: Positron emission tomography (PET) imaging is a non-invasive functional imaging method used to reflect tumor spatial information, and to provide biological characteristics of tumor progression. The aim of this study was to focus on the application of 18F-fluoromisonidazole (FMISO) PET quantitative parameter of maximum standardized uptake value (SUVmax) ratio to detect the liver metastatic potential of human colorectal cancer (CRC) in mice. METHODS: Colorectal liver metastases (CRLM) xenograft models were established by injecting tumor cells (LoVo, HT29 and HCT116) into spleen of mice, tumor-bearing xenograft models were established by subcutaneously injecting tumor cells in the right left flank of mice. Wound healing assays were performed to examine the ability of cell migration in vitro. 18F-FMISO uptake in CRC cell lines was measured by cellular uptake assay. 18F-FMISO-based micro-PET imaging of CRLM and tumor-bearing mice was performed and quantified by tumor-to-liver SUVmax ratio. The correlation between the 18F-FMISO SUVmax ratio, liver metastases number, hypoxia-induced factor 1α (HIF-1α) and serum starvation-induced glucose transporter 1 (GLUT-1) was evaluated using Pearson correlation analysis. RESULTS: Compared with HT29 and HCT116, LoVo-CRLM mice had significantly higher liver metastases ratio and shorter median survival time. LoVo cells exhibited stronger migration capacity and higher radiotracer uptake compared with HT29 and HCT116 in in vitro. Moreover, 18F-FMISO SUVmax ratio was significantly higher in both LoVo-CRLM model and LoVo-bearing tumor model compared to models established using HT29 and HCT116. In addition, Pearson correlation analysis revealed a significant correlation between 18F-FMISO SUVmax ratio of CRLM mice and number of liver metastases larger than 0.5 cm, as well as between 18F-FMISO SUVmax ratio and HIF-1α or GLUT-1 expression in tumor-bearing tissues. CONCLUSIONS: 18F-FMISO parameter of SUVmax ratio may provide useful tumor biological information in mice with CRLM, thus allowing for better prediction of CRLM and yielding useful radioactive markers for predicting liver metastasis potential in CRC.

Prediction of tumor biological characteristics in different colorectal cancer liver metastasis animal models using 18F-FDG and 18F-FLT.

BACKGROUND: Positron emission tomography (PET) is a noninvasive method to characterize different metabolic activities of tumors, providing information for staging, prognosis, and therapeutic response of patients with cancer. The aim of this study was to evaluate the feasibility of 18F-fludeoxyglucose (18F-FDG) and 3'-deoxy-3'-18F-fluorothymidine (18F-FLT) PET in predicting tumor biological characteristics of colorectal cancer liver metastasis. METHODS: The uptake rate of 18F-FDG and 18F-FLT in SW480 and SW620 cells was measured via an in vitro cell uptake assay. The region of interest was drawn over the tumor and liver to calculate the maximum standardized uptake value ratio (tumor/liver) from PET images in liver metastasis model. The correlation between tracer uptake in liver metastases and VEGF, Ki67 and CD44 expression was evaluated by linear regression. RESULTS: Compared to SW620 tumor-bearing mice, SW480 tumor-bearing mice presented a higher rate of liver metastases. The uptake rate of 18F-FDG in SW480 and SW620 cells was 6.07% ±â€¯1.19% and 2.82% ±â€¯0.15%, respectively (t = 4.69, P = 0.04); that of 18F-FLT was 24.81% ±â€¯0.45% and 15.57% ±â€¯0.66%, respectively (t = 19.99, P < 0.001). Micro-PET scan showed that all parameters of FLT were significantly higher in SW480 tumors than those in SW620 tumors. A moderate relationship was detected between metastases in the liver and 18F-FLT uptake in primary tumors (r = 0.73, P = 0.0019). 18F-FLT uptake was also positively correlated with the expression of CD44 in liver metastases (r = 0.81, P = 0.0049). CONCLUSIONS: The uptake of 18F-FLT in metastatic tumor reflects different biological behaviors of colon cancer cells. 18F-FLT can be used to evaluate the metastatic potential of colorectal cancer in nude mice.

Using receiver operating characteristic curves to evaluate the diagnostic value of the combination of multislice spiral CT and alpha-fetoprotein levels for small hepatocellular carcinoma in cirrhotic patients.

BACKGROUND: The various combination of multiphase enhancement multislice spiral CT (MSCT) makes the diagnosis of a small hepatocellular carcinoma (sHCC) on the background of liver cirrhosis possible. This study was to explore whether the combination of MSCT enhancement scan and alpha-fetoprotein (AFP) level could increase the diagnostic efficiency for sHCC. METHODS: This study included 35 sHCC patients and 52 cirrhotic patients without image evidence of HCC as a control group. The diagnoses were made by three radiologists employing a 5-point rating scale, with postoperative pathologic results as the gold standard. Receiver operating characteristic (ROC) curve analysis was performed to evaluate the diagnostic value of the three MSCT combination modes (arterial phase+portal-venous phase, arterial phase+delayed phase, arterial phase+portal-venous phase+delayed phase) and AFP levels for sHCC on the background of liver cirrhosis. RESULTS: The area under ROC curve (AUC), sensitivity, and specificity of the combination of arterial phase+portal-venous phase+delayed phase were 0.93, 93%, and 82%, respectively. The average AUC of the arterial phase+portal-venous phase+delayed phase combination was significantly greater than that of the arterial phase+portal-venous phase (AUC=0.84, P=0.01) and arterial phase+delayed phase (AUC=0.85, P=0.03). Arterial phase+portal-venous phase had a smaller AUC (0.84) than arterial phase+delayed phase (0.85), but the difference was insignificant (P=0.15). After combining MSCT enhancement scan with AFP, the AUC, sensitivity, and specificity were 0.95, 94%, and 83%, respectively, indicating a greatly increased diagnostic efficiency for sHCC. CONCLUSIONS: The combination of AFP and 3 phases MSCT enhancement scan could increase the diagnostic efficiency for sHCC on the background of liver cirrhosis. The application of ROC curve analysis has provided a new method and reference in HCC diagnosis.

Metabolic alteration of Tetrahymena thermophila exposed to CdSe/ZnS quantum dots to respond to oxidative stress and lipid damage.

CdSe/ZnS Quantum dots (QDs) are possibly released to surface water due to their extensive application. Based on their high reactivity, even small amounts of toxicant QDs will disturb water microbes and pose a risk to aquatic ecology. Here, we evaluated CdSe/ZnS QDs toxicity to Tetrahymena thermophila (T. thermophila), a model organism of the aquatic environment, and performed metabolomics experiments. Before the omics experiment was conducted, QDs were found to induce inhibition of cell proliferation, and reactive oxygen species (ROS) production along with Propidium iodide labeled cell membrane damage indicated oxidative stress stimulation. In addition, mitochondrial ultrastructure alteration of T. thermophila was also confirmed by Transmission Electron Microscope results after 48 h of exposure to QDs. Further results of metabolomics detection showed that 0.1 µg/mL QDs could disturb cell physiological and metabolic metabolism characterized by 18 significant metabolite changes, of which twelve metabolites improved and three decreased significantly compared to the control. Kyoto Encyclopedia of Genes and Genomes analysis showed that these metabolites were involved in the ATP-binding cassette transporter and purine metabolism pathways, both of which respond to ROS-induced cell membrane damage. In addition, purine metabolism weakness might also reflect mitochondrial dysfunction associated with energy metabolism and transport abnormalities. This research provides deep insight into the potential risks of quantum dots in aquatic ecosystems.

A water stable layered Tb(iii) polycarboxylate with high proton conductivity over 10-2 S cm-1 in a wide temperature range.

An unprecedented Tb(iii) polycarboxylate, {[Tb4(TTHA)2(H2O)4]·7H2O}n (1), has been synthesized. It possesses an efficient proton transfer pathway formed by water molecules and carboxyl groups, which exhibits proton conductivity over 10-2 S cm-1 at 295-358 K and 98% relative humidity.

Interaction of XRCC1 Arg399Gln Polymorphism and Alcohol Consumption Influences Susceptibility of Esophageal Cancer.

Background. To explore the correlation between the Arg399Gln polymorphism and susceptibility to esophageal cancer in Korean and Han Chinese individuals in Harbin, China, and its potential interaction with alcohol consumption. Methods. This prospective study included 203 patients with esophageal squamous cell carcinoma; 88 were of Korean descent and 115 were of Han Chinese descent. A group of healthy controls included 105 participants of Korean descent and 105 of Han Chinese descent. Genotyping of the Arg399Gln locus of XRCC1 was performed by PCR-RFLP. Results. The allelic and genotypic frequencies were not significantly different between individuals with esophageal cancer and controls or between individuals of Korean and Han Chinese descent (P > 0.05). However, when individuals with the wild-type Arg/Arg genotype also consumed alcohol, the risk of esophageal cancer was lower (OR = 3.539; 95% CI = 2.039-6.142; P < 0.05). Conclusions. The XRCC1 Arg399Gln polymorphism does not appear to be associated with esophageal cancer in individuals of Korean or Han Chinese descent in Harbin, China. However, alcohol consumption may decrease the risk of esophageal cancer in persons with the wild-type genotype.