Corrigendum: CircAFF1 aggravates vascular endothelial cell dysfunction mediated by miR-516b/SAV1/YAP1 axis.

[This corrects the article DOI: 10.3389/fphys.2020.00899.].

Ultrasound and elastography role in pre- and post-operative evaluation of median neuropathy in patients with carpal tunnel syndrome.

Introduction: Carpal tunnel syndrome (CTS) is a common compression neuropathy of the median nerve in the wrist. Early diagnosis of CTS is essential for selecting treatment options and assessing prognosis. The current diagnosis of CTS is based on the patient's clinical symptoms, signs, and an electromyography (EMG) test. However, they have some limitations. Recently, ultrasound has been adopted as an adjunct diagnostic tool for electromyography (EMG). Ultrasound is a non-invasive and cost-effective technique. It provides a dynamic display of morphological changes in the median nerve and an assessment of CTS etiology such as tenosynovitis, mass compression, and tendon disease. This study aimed to investigate the value of conventional ultrasound and real-time shear wave elastography (SWE) in evaluation of median neuropathy in patients with carpal tunnel syndrome (CTS) before and after surgery. Methods: First, the Boston Carpal Tunnel Questionnaire (BCTQ) was administered to patients with CTS. All subjects were measured at three levels: the distal 1/3 of the forearm, the carpal tunnel inlet, and the distal carpal tunnel using conventional ultrasound and SWE. Median nerve parameters were examined in patients with CTS 1 week after surgery. Results: The cross-sectional area (CSA) and stiffness of the median nerve at the carpal tunnel inlet and distal carpal tunnel were significantly higher in patients with CTS than in healthy controls (p < 0.001). The CSA and stiffness of the median nerve at the carpal tunnel inlet were statistically significantly significantly between pre- and postoperative patients with CTS (p < 0.001). The CSA and stiffness of the nerve in patients with CTS had a positive correlation with electrophysiology severity. Conclusions and discussion: Conventional ultrasound and elastography are valuable in the diagnosis of CTS and are useful in the clinical assessment of patient's nerve recovery after operation.

circAFF1 Aggravates Vascular Endothelial Cell Dysfunction Mediated by miR-516b/SAV1/YAP1 Axis.

Pathological vascular endothelial damage caused by hypoxia is the basis of many vascular-related diseases. However, the role of circular RNA in hypoxic vascular injury is still poorly understood. Here, we found that hypoxia induced AFF1 circular RNA (circAFF1) can activate the SAV1/YAP1 and lead to the dysfunction of vascular endothelial cells. In HUV-EC-C and HBEC-5i cells, circAFF1 was upregulated under CoCl2 induced hypoxic conditions. The abnormal expression of circAFF1 inhibited the proliferation, tube formation, migration of vascular endothelial cells. The effect of circAFF1 is achieved by the adsorption of miR-516b to release SAV1, which in turn causes the phosphorylation of YAP1. Moreover, we found that the upregulation of circAFF1 in 235 Patients with subarachnoid hemorrhage. Taken together, we clarify the role of circAFF1/miR-516b/SAV1/YAP1 axis in vascular endothelial dysfunction and its potential early diagnostic value of disease caused by hypoxia injury in blood vessels.

Type II heterojunction in hierarchically porous zinc oxide/graphitic carbon nitride microspheres promoting photocatalytic activity.

Graphitic carbon nitride (g-C3N4) is a visible light active semiconductor. However, low conductivity and high recombination rate of photogenerated electrons and holes limit its application in photocatalysis. In this work, we design and synthesize hierarchically porous zinc oxide/graphitic carbon nitride (ZnO/g-C3N4) microspheres with type-II heterojunction to effectively degrade rhodamine B (RhB) via increasing the charge-separation efficiency. The ultraviolet-visible (UV-Vis) absorption spectra, Mott-Schottky plots and valence band X-ray photoelectron spectroscope confirm the formation of type-II heterojunction between ZnO nanocrystals and g-C3N4 nanosheets. As a result, the 1.5-ZnO/g-C3N4 composite (the mass ratio of zinc acetate dihydrate to g-C3N4 is 1.5) exhibits the highest photocatalytic activity with good stability and higher photocatalytic degradation rate comparing to pure g-C3N4 and pure ZnO. In addition, our results confirm that O2- and h+ are the main active species for ZnO/g-C3N4 in degradation of RhB.

Note: A simple charge neutralization method for measuring the secondary electron yield of insulators.

We report on a simple and effective charge neutralization method for measuring the total electron-induced secondary electron yield of insulators in a measurement system with a single pulsed electron gun. In this method, the secondary electron collector is negatively biased with respect to the sample to force some emitted secondary electrons to return to the sample surface and therefore to neutralize positive charges accumulated in the sample during the previous measurement. The adequate negative bias is determined and the equilibrium state of negative charging is discussed. The efficacy of the method is demonstrated by the measured electron yields in the cases with and without charge neutralization and by comparison with existing electron yield data of polyimide.

Chemo-enzymatic synthesis of allyl penta-N-acetyl-chitopentaose.

Cell density cultivation of recombinant Escherichia coli strains harboring the nodC gene (encoding chitooligosaccharide synthase) from Azorhizobium caulinodans has been previously described as a practical method for the preparation of gram-scale quantities of penta-N-acetyl-chitopentaose. We have now extended this method to the production of allylated derivative of penta-N-acetyl-chitopentaose by using allyl 2-acetamido-2-deoxy-beta-d-glucopyranoside (2) as the initial acceptor for the synthesis of target pentaoside in vivo.

Chemo-enzymatic synthesis of 1,4-oxazepanyl sugar as potent inhibitor of chitinase.

N-acetyl glucosamine 1 is selectively converted into 2 without protection of the other hydroxyl groups by allylation of the anomeric alkoxide in N,N-dimethylformamide containing lithium bromide. We use cell density cultures to produce the allylated derivative of penta-N-acetyl-chitopentaose by using 2 as the initial acceptor for the synthesis of 3 in vivo. Upon periodate oxidation, 3 is transferred to 4. Compound 4 is quickly subjected to sodium borohydride reduction and NH3 amination, which afforded the target compound 5. In 5-binding chitinase assay, it indicates that the chitinase is obviously inactivated by 5 with IC50 = 4.7 micromol/L.

Stereoselective synthesis of beta-amino acids.

A convenient method for the stereoselective syntheses of beta-amino acids with alpha-substitutions has been developed. This synthetic route involves the preparation of isoxazolidinones through hydroxylamine addition to unsaturated esters and subsequent hydrogenation. This procedure is also useful for the stereoselective syntheses of alpha-deuterated beta-amino acids.