Improving the Signal-to-Noise Ratio of Axial Displacement Measurements of Microspheres Based on Compound Digital Holography Microscopy Combined with the Reconstruction Centering Method.

In 3D microsphere tracking, unlike in-plane motion that can be measured directly by a microscope, axial displacements are resolved by optical interference or a diffraction model. As a result, the axial results are affected by the environmental noise. The immunity to environmental noise increases with measurement accuracy and the signal-to-noise ratio (SNR). In compound digital holography microscopy (CDHM)-based measurements, precise identification of the tracking marker is critical to ensuring measurement precision. The reconstruction centering method (RCM) was proposed to suppress the drawbacks caused by installation errors and, at the same time, improve the correct identification of the tracking marker. The reconstructed center is considered to be the center of the microsphere, rather than the center of imaging in conventional digital holographic microscopy. This method was verified by simulation of rays tracing through microspheres and axial moving experiments. The axial displacements of silica microspheres with diameters of 5 µm and 10 µm were tested by CDHM in combination with the RCM. As a result, the SNR of the proposed method was improved by around 30%. In addition, the method was successfully applied to axial displacement measurements of overlapped microspheres with a resolution of 2 nm.

Visible-Light Promoted Distereodivergent Intramolecular Oxyamidation of Alkenes.

The visible-light-promoted diastereodivergent intramolecular oxyamination of alkenes is described to construct oxazolindinones, pyrrolidinones and imidazolidones via mild generation of primary amidyl radicals from functionalized hydroxylamines. A unique phenomenon of highly diastereoselective ring-opening of aziridines controlled by electron sacrifices was observed. Highly diastereoselective amino alcohols derivatives were obtained efficiently through this protocol in gram scales. The mechanistic studies suggested the isolatable anti-aziridine intermediates were generated quickly from primary amidyl radicals and the diastereoselectivities were controlled by pKa values of the electron sacrifices.

Upregulation of RACGAP1 is correlated with poor prognosis and immune infiltration in hepatocellular carcinoma.

Background: Hepatocellular carcinoma (HCC) is a primary liver cancer with high mortality worldwide. Even though the patients with HCC received standard therapies, patients with HCC continue to experience unsatisfactory therapy outcomes. Presently, immune therapy acts as a novel therapeutic management for HCC. The aim of this study was to determine overexpressed genes in HCC and evaluate the association between overexpressed genes with the prognosis and immune infiltration. Methods: Gene expression profiles of HCC were analyzed using multiple online databases, and then confirmed by qualitative real time-polymerase chain reaction (RT-qPCR) and immunohistochemical analysis. The correlations of gene overexpression with the prognosis and immune infiltration were determined. Results: Top 11 common differentially expressed genes were identified in HCC, and RACGAP1 was selected for further analysis. RACGAP1 expression was significantly higher in HCC tissues than that in normal tissues. Upregulation of RACGAP1 was correlated with clinical stage and poor prognosis. Additionally, RACGAP1 overexpression was positively related to the infiltration of suppressive immune cells. Moreover, we speculate RACGAP1 may promote tumorigenesis of HCC through immunosuppression mediated by YAP activation. Conclusions: Overexpression of RACGAP1 was associated with unfavorable prognosis and immune infiltration in HCC, which indicated that RACGAP1 could be a molecular target for HCC.

Visible-light promoted intramolecular carboamination of alkynes for the synthesis of oxazolidinone-fused isoquinolinones.

An efficient method for the synthesis of isoquinolinone derivatives via photopromoted carboamination of alkynes is developed. Starting from the readily available propargyl alcohol derivatives, the polycyclic isoquinolinone derivatives could be obtained with good aryl and heterocycle tolerance. Both terminal and alkyl substituted alkynes could be employed. This protocol is operationally easy, and easily conducted on a gram-scale. A possible mechanism involving radical addition and cyclization following aromatization was proposed.

MiR-26b-5p-modified hUB-MSCs derived exosomes attenuate early brain injury during subarachnoid hemorrhage via MAT2A-mediated the p38 MAPK/STAT3 signaling pathway.

Early brain injury (EBI) is a major cause of adverse outcomes following subarachnoid hemorrhage (SAH). There is evidence that mesenchymal stem cells (MSCs) - derived exosomes are involved in the repair of SAH. Exosomes were extracted from human umbilical cord mesenchymal stem cells (hubMSCs) and identified. OxyHb treated PC12 cells were transfected with exosomes alone or together with miR-26b-5p inhibitor. Hub-MSCs derived exosomes promote cell proliferation, inhibit apoptosis and reduce inflammatory mediator expression. Transfection of miR-26b-5p inhibitor abolished the promoting effect of exosomes on the proliferation of PC12 cells, as well as the inhibitory effect on cell apoptosis. In addition, methionine adenosyltransferase II alpha (MAT2A) was one target gene of miR-26b-5p. OxyHb treated PC12 cells were transfected with exosomes alone or together with pcDNA-MAT2A and observed that the promoting effect of exosomes on PC12 cell proliferation was abolished by pcDNA-MAT2A, which was the same as the effect of miR-26b-5p inhibitor. OxyHb treated PC cells incubated with exosomes were transfected with miR-26b-5p inhibitor alone or together with si-MAT2A, respectively, and it was observed that exosomes decreased the phosphorylation levels of p38 MAPK and STAT3 proteins, inhibited cell apoptosis and inflammatory mediator expression, and miR-26b-5p inhibitor abrogated the effects of exosomes, while transfection of si-MAT2A reversed the effects of miR-26b-5p inhibitor. Moreover, injection of miR-26b-5p inhibitor resulted in increased MAT2A and pathway protein expression, increased inflammatory mediators, and aggravated neurological symptoms in the brain tissues of SAH rats.

Controllable Intramolecular Unactivated C(sp3)-H Amination and Oxygenation of Carbamates.

Dual catalyst-controlled intramolecular unactivated C(sp3)-H amination and oxygenation of carbamates merging visible-light photocatalysis and earth-abundant transition metal catalysis have been reported. Useful amino alcohol and diol derivatives could be selectively obtained from readily available tertiary alcohol derivatives. The possible mechanisms have been proposed via a 1,5-HAT process followed by Lewis acid-controlled cyclization. The nickel and zinc catalysts inhibit the formation of oxygenation and amination products, respectively. An interesting phenomenon of chirality transfer is also observed.

Comparison of nighttime and daytime operation on outcomes of kidney transplant with deceased donors: a retrospective analysis.

BACKGROUND: Kidney transplant is always emergent operations and frequently need to be performed at nighttime to reduce cold ischemia time (CIT). Previous studies have revealed that fatigue and sleep deprivation can result in adverse consequences of medical procedures. This study aimed to evaluate whether nighttime operation has adverse impact on kidney transplant. METHODS: A retrospective analysis of recipients accepted kidney transplant from deceased donors in one center from 2014 to 2016 was performed. Daytime transplant was defined as operation started after 8 AM or ended before 8 PM and nighttime operation was defined as operation ended after 8 PM or started before 8 AM. The incidences of complications such as delayed graft function, acute rejection, surgical complications and nosocomial infections were compared between 2 groups. Student's t-test was used to analyze continuous variables such as serum creatinine (Scr) at 1-year of post-transplant. The Chi-square test was used to analyze categorical variables. Differences in recipients and graft survival were analyzed using Kaplan-Meier methodology and log-rank tests. RESULTS: Among the 443 recipients, 233 (52.6%) were classified into the daytime group and the others 210 (47.4%) were in the nighttime group. The 1-year survival rate of recipients was similar for the recipients in the daytime and nighttime groups (95.3% vs. 95.2%, P = 0.981). Although the 1-year graft survival rate in the nighttime group was slightly superior to that in the daytime group, the difference was not significant (92.4% vs. 88.4%, P = 0.164). Furthermore, Scr and incidence of complications were also not significantly different between the 2 groups. CONCLUSIONS: Our results suggested that operation time of kidney transplant with short CIT has no significant impact on the outcome of kidney transplant. Nighttime operation of kidney transplant with short CIT could be postponed to the following day to alleviate the burden on medical staffs and avoid the potential risk.