Transformation Pathway from CdSe Magic-Size Clusters with Absorption Doublets at 373/393†nm to Clusters at 434/460†nm.

Divergent interpretations have appeared in the literature regarding the structural nature and evolutionary behavior for photoluminescent CdSe nanospecies with sharp doublets in optical absorption. We report a comprehensive description of the transformation pathway from one CdSe nanospecies displaying an absorption doublet at 373/393 nm to another species with a doublet at 433/460 nm. These two nanospecies are zero-dimensional (0D) magic-size clusters (MSCs) with 3D quantum confinement, and are labeled dMSC-393 and dMSC-460, respectively. Synchrotron-based small-angle X-ray scattering (SAXS) returns a radius of gyration of 0.92 nm for dMSC-393 and 1.14 nm for dMSC-460, and indicates that both types are disc shaped with the exponent of the SAXS form factor equal to 2.1. The MSCs develop from their unique counterpart precursor compounds (PCs), which are labeled PC-393 and PC-460, respectively. For the dMSC-393 to dMSC-460 transformation, the proposed PC-enabled pathway is comprised of three key steps, dMSC-393 to PC-393 (Step 1), PC-393 to PC-460 (Step 2 involving monomer addition), and PC-460 to dMSC-460 (Step 3). The present study provides a framework for understanding the PC-based evolution of MSCs and how PCs enable transformations between MSCs.

Evaluation of Procalcitonin and C-reactive Protein in Early Differential Diagnosis of Neonatal Jaundice.

BACKGROUND: The purpose of this study was to investigate the clinical value of procalcitonin (PCT) and C-reactive protein (CRP) in the differential diagnosis of neonatal jaundice. METHODS: Eighty-five cases of neonatal jaundice in our hospital from January 2016 to March 2019 were selected as research subjects, including 30 cases of physiological jaundice, 23 cases of infectious jaundice, and 32 cases of he-molytic jaundice. Five milliliters of non-anticoagulated venous peripheral blood and 3 mL EDTA-K+ anticoagulated venous peripheral blood were sampled from each newborn when the symptoms of jaundice occurred. The non-anticoagulated blood samples were then centrifuged at 3,500 rpm for 7 minutes and the serum was used for PCT and bilirubin examinations, and the anticoagulated blood samples were prepared for CRP examination. Receiver operating characteristic (ROC) curve analysis was performed for the evaluation of differential diagnosis of neonatal jaundice by PCT, CRP, and bilirubin levels. RESULTS: Analyses of variance showed the postnatal age of jaundice occurring in the physiological jaundice group was older than those in the infectious jaundice and hemolytic jaundice groups (p < 0.001), and the PCT and CRP levels in the infectious jaundice group were higher than those in the hemolytic jaundice and physiological jaundice groups (p < 0.001). Pearson's correlation analysis indicated that the levels of PCT and CRP were negatively correlated with postnatal age in the physiological jaundice group (p < 0.05). ROC curve analysis demonstrated that PCT and CRP had the highest differential diagnosis efficacy of neonatal pathological and neonatal physiological jaundice with PCT and CRP at 0.70 µg/L and 8.50 mg/L, respectively, as well as the highest differential diagnosis efficacy of neonatal infectious jaundice and neonatal hemolytic jaundice with PCT and CRP at 1.84 µg/L and 13.50 mg/L, respectively. CONCLUSIONS: This study suggested that PCT and CRP possessed important clinical values in the differential diagnosis of neonatal jaundice, and PCT was superior to the differential diagnosis of neonatal infectious jaundice.

MicroRNA-194 inhibition improves dietary-induced non-alcoholic fatty liver disease in mice through targeting on FXR.

Non-alcoholic fatty liver disease (NAFLD) affects obesity-associated metabolic syndrome, which exhibits hepatic steatosis, insulin insensitivity and glucose intolerance. Previous studies indicated that hepatic microRNAs (miRs) play critical roles in the development of NAFLD. In this study, we aim to explore the pathophysiological role of miR-194 in obesity-mediated metabolic dysfunction. Our findings show that the high fat diet or palmitic acid treatment significantly increase hepatic miR-194 levels in vivo and in vitro. Silence of miR-194 protects palmitic acid-induced inflammatory response in cultured hepatocytes, and attenuates structural disorders, lipid deposits and inflammatory response in fatty liver. MiR-194 inhibitor also improves glucose and insulin intolerance in obese mice. Through dual luciferase assay, we demonstrate that miR-194 directly binds to FXR/Nr1h4 3'-UTR, and inhibits gene expression of FXR/Nr1h4. Furthermore, overexpression of miR-194 downregulates FXR/Nr1h4 in cultured hepatocytes, but miR-194 inhibitor reversely increases FXR/Nr1h4 expression in obese mouse liver tissues. On the contrast, silence of FXR/Nr1h4 abolishes the hepatic benefits in obese mice treated with miR-194 inhibitor. Present study provides a novel finding that suppression of miR-194 attenuates dietary-induced NAFLD via upregulation of FXR/Nr1h4. The findings suggest miR-194/FXR are potential diagnostic markers and therapeutic targets for NAFLD.

Room-Temperature Evolution of Ternary CdTeS Magic-Size Clusters Exhibiting Sharp Absorption Peaking at 381 nm.

Colloidal semiconductor ternary CdTeS magic-size clusters (MSCs) have not been reported. Here, we present the first synthesis of CdTeS MSCs at room temperature and our understanding of the evolution pathway. The MSCs exhibit sharp optical absorption peaking at 381 nm and are labeled MSC-381. CdTeS MSC-381 evolves when pre-nucleation-stage samples of binary CdTe and CdS that do not contain quantum dots (QDs) are separately prepared and then mixed and incubated at room temperature. We propose that CdTeS MSC-381 evolves from its precursor compound (PC) via quasi-isomerization. Synchrotron-based small-angle X-ray scattering suggests that PCs/MSCs of CdTe and CdTeS are similar in sizes. We propose further that the CdTeS PC forms from the substitution reaction between the CdTe PC and the CdS monomer/fragment (Mo/Fr). The present study paves the way to the room-temperature evolution of ternary MSCs and provides an in-depth understanding of the PC to MSC transformation.

Transformation Pathway from CdSe Nanoplatelets with Absorption Doublets at 373/393 nm to Nanoplatelets at 434/460 nm.

For those colloidal semiconductor CdSe nanospecies that exhibit sharp optical absorption doublets, different explanations have appeared in the literature regarding their morphological nature and formation, with no consensus reached. Here, we discuss the transformation pathway in two types of CdSe nanoplatelets (NPLs), from NPL-393 to NPL-460, exhibiting absorption doublets at 373/393 and 433/460 nm, respectively. Synchrotron-based small/wide-angle X-ray scattering (SAXS/WAXS) was performed to monitor the in situ transformation associated with the temperature. Combining the results of SAXS/WAXS, optical spectroscopy, and transmission electron microscopy, we propose that the transformation pathway experiences corresponding magic-sized clusters (MSCs), which display similar optical properties but with zero-dimensional structure. From stacked NPL-393 to stacked NPL-460, the transformation goes through sequentially individual NPL-393, MSC-393, MSC-460, and individual NPL-460 at their corresponding characteristic temperature. The present findings provide compelling evidence that both MSCs and their assembled NPLs exhibit similar optical absorption.

In situ SAXS probing the evolution of the precursors and onset of nucleation of ZnSe colloidal semiconductor quantum dots.

The whole evolution processes, from precursors to quantum dots (QDs), were in situ investigated by SAXS and UV-vis. Diphenylphosphine (HPPh2) accelerates the dissolution of zinc oleate lamellar mesophase in the presence of selenide tri-n-octylphosphine (SeTOP) at a low temperature of 40 °C via the equilibrium of SeTOP + HPPh2 ⇔ SePPh2H + TOP.

[Plasma miRNA-23a and miRNA-451 as candidate biomarkers for early diagnosis of nonsmall cell lung cancer: a case-control study].

OBJECTIVE: To study the value of plasma miRNA23-a and miRNA-451 as potential biomarkers for early diagnosis of non-small cell lung cancer (NSCLC). METHODS: Fifty patients with NSCLC and 50 healthy control subjects were recruited for testing the plasma levels of miRNA23-a and miRNA-451 and their expression levels in the tumor tissues using qRT-PCR. The correlations of the plasma levels of miRNA23-a and miRNA-451 with their expressions in the tumor tissues were analyzed. The diagnostic power of CEA, miRNA23-a and miRNA-451 for NSCLC was evaluated using the receiver-operating characteristics (ROC) curves and the area under the ROC curves (AUC). In the NSCLC cell line A549, we tested the effect of inhibition of miRNA-23a and miRNA-451 on the expression levels of SPRY2 and MIF mRNA using qRT-PCR. RESULTS: The expression levels of miRNA-23a and miRNA-451 in NSCLC tissues was significantly associated with smoking, tumor size, lymph node metastasis and TNM stage (P < 0.05). Compared with those in the control group, miRNA-23a level was significantly increased while miRNA-451 was significantly down-regulated in the tumor tissues and plasma of NSCLC patients. The plasma levels of miRNA-23a and miRNA-45 were strongly correlated with their expression levels in the tumor tissues. ROC analysis showed that for the diagnosis of NSCLC, the AUC, sensitivity and specificity of either miRNA-23a or miRNA-451 were significantly higher than those of CEA (P < 0.05). The combination of miRNA23-a and miRNA-451 markedly improved the AUC (0.900), sensitivity (78%) and specificity (86%) for the diagnosis. In A549 cells, inhibition of miRNA23-a and miRNA-451 resulted in significantly increased expression levels of SPRY2 mRNA and MIF mRNA, respectively. CONCLUSIONS: miRNA-23a and miRNA-451 can be used as potential biomarkers for early diagnosis of NSCLC, and their combined detection can be more effective for the diagnosis.

Strain Engineered CaBi2Nb2O9 Thin Films with Enhanced Electrical Properties.

In this work, strain engineered polycrystalline thin films (∼250 nm) of bismuth layer-structured ferroelectric (BLSF) CaBi2Nb2O9 (CBNO) were prepared by using a radio frequency (RF) magnetron sputtering technique. XRD analysis revealed that the films were (200)/(020) and (00l) textured with a large in-plane tensile stress. Cross-sectional TEM analyses confirmed the bismuth layered-structure, as well as crystalline orientations and a strain-controlled growth mode of the grains. Result of a quantitative XPS analysis revealed that the composition of the film is close to the chemical stoichiometry. Excellent electrical properties were achieved in the CBNO films, including a high dielectric constant (∼280 @5 kHz), a small dielectric loss (tgδ ≤ 1.6% up to an applied electric field of ∼1200 kV/cm) and a large polarization (Pr ≈ 14 µC/cm(2) @ 1 kHz).