Distinctive p-d Orbital Hybridization in CuSb Porous Nanonetworks for Enhanced Nitrite Electroreduction to Ammonia.

Electrochemical nitrite reduction reaction ( NO 2 - RR ${\mathrm{NO}}_{\mathrm{2}}^{\mathrm{ - }}{\mathrm{RR}}$ ), as a green and sustainable ammonia synthesis technology, has broad application prospects and environmental friendliness. Herein, an unconventional p-d orbital hybridization strategy is reported to realize the fabrication of defect-rich CuSb porous nanonetwork (CuSb PNs) electrocatalyst for NO 2 - RR ${\mathrm{NO}}_{\mathrm{2}}^ - {\mathrm{RR}}$ . The crystalline/amorphous heterophase structure is cleverly introduced into the porous nanonetworks, and this defect-rich structure exposes more atoms and activated boundaries. CuSb PNs exhibit a large NH3 yield ( r N H 3 ${{r}_{{\mathrm{N}}{{{\mathrm{H}}}_{\mathrm{3}}}}}$ ) of 946.1 µg h-1 m cat - 1 ${\mathrm{m}}_{{\mathrm{cat}}}^{ - {\mathrm{1}}}$ and a high faradaic efficiency (FE) of 90.7%. Experimental and theoretical studies indicate that the excellent performance of CuSb PNs results from the defect-rich porous nanonetworks structure and the p-d hybridization of Cu and Sb elements. This work describes a powerful pathway for the fabrication of p-d orbital hybrid defect-rich porous nanonetworks catalysts, and provides hope for solving the problem of nitrogen oxide pollution in the field of environment and energy.

Chemerin as an Inducer of ß Cell Proliferation Mediates Mitochondrial Homeostasis and Promotes ß Cell Mass Expansion.

Loss of the ß cell population is a crucial feature of type 2 diabetes. Restoring the ß cell mass by stimulating ß cell proliferation and preventing its apoptosis was proposed as a therapeutic approach to treating diabetes. Therefore, researchers have been increasingly interested in identifying exogenous factors that can stimulate ß cell proliferation in situ and in vitro. Adipokine chemerin, which is secreted from adipose tissue and the liver, has been identified as a chemokine that plays a critical role in the regulation of metabolism. In this study, we demonstrate that chemerin as a circulating adipokine promotes ß cell proliferation in vivo and in vitro. Chemerin serum levels and the expression of the main receptors within islets are highly regulated under a variety of challenging conditions, including obesity and type 2 diabetes. As compared to their littermates, mice overexpressing chemerin had a larger islet area and increased ß cell mass with both a normal and high-fat diet. Moreover, in chemerin-overexpressed mice, we observed improved mitochondrial homeostasis and increased insulin synthesis. In summary, our findings confirm the potential role of chemerin as an inducer of ß cell proliferation, and they provide novel insights into the helpful strategy to expand ß cell population.

Early changes to retinal structure in patients with diabetic retinopathy as determined by ultrawide swept-source optical coherence tomography-angiography.

Purpose: To investigate retinal vascular changes in patients with diabetic retinopathy (DR) using the newly developed ultrawide rapid scanning swept-source optical coherence tomography angiography (SS-OCTA) device. Methods: This cross-sectional, observational study enrolled 24 patients (47 eyes) with DR, 45 patients (87 eyes) with diabetes mellitus (DM) without DR, and 36 control subjects (71 eyes). All subjects underwent 24 × 20 mm SS-OCTA examination. Vascular density (VD) and the thickness of the central macula (CM; 1 mm diameter) and temporal fan-shaped areas of 1-3 mm (T3), 3-6 mm (T6), 6-11 mm (T11), 11-16 mm (T16), and 16-21 mm (T21) were compared among groups. The VD and the thicknesses of the superficial vascular complex (SVC) and deep vascular complex (DVC) were analyzed separately. The predictive values of VD and thickness changes in DM and DR patients were evaluated by receiver operating characteristic (ROC) curve analysis. Results: The average VDs of the SVC in the CM and the T3, T6, T11, T16, and T21 areas were significantly lower in the DR than in the control group, whereas only the average VD of the SVC in the T21 area was significantly lower in the DM group. The average VD of the DVC in the CM was significantly increased in the DR group, whereas the average VDs of the DVC in the CM and T21 area were significantly decreased in the DM group. Evaluation of the DR group showed significant increases in the thicknesses of SVC-nourishing segments in the CM and T3, T6, and T11 areas and significant increases in the thicknesses of DVC-nourishing segments in the CM and T3 and T6 areas. In contrast, none of these parameters showed significant changes in the DM group. ROC curve analysis showed that the average VD of the SVC in the CM, T3, and T21 had better ability to predict DR, with areas under the ROC curves (AUCs) of 0.8608, 0.8505, and 0.8353, respectively. The average VD of the DVC in the CM was also predictive of DR, with an AUC of 0.8407. Conclusions: The newly developed ultrawide SS-OCTA device was better able to reveal early peripheral retinal vascular changes than traditional devices.

Different scan areas affect the detection rates of diabetic retinopathy lesions by high-speed ultra-widefield swept-source optical coherence tomography angiography.

Introduction: The study aimed to determine the effect of the scanning area used for high-speed ultra-widefield swept-source optical coherence tomography angiography (SS-OCTA) on the detection rate of diabetic retinopathy (DR) lesions. Methods: This prospective, observational study involved diabetic patients between October 2021 and April 2022. The participants underwent a comprehensive ophthalmic examination and high-speed ultra-widefield SS-OCTA using a 24 mm × 20 mm scanning protocol. A central area denoted as "12 mm × 12 mm-central" was extracted from the 24 mm × 20 mm image, and the remaining area was denoted as "12 mm~24mm-annulus." The rates of detection of DR lesions using the two scanning areas were recorded and compared. Results: In total, 172 eyes (41 eyes with diabetes mellitus without DR, 40 eyes with mild to moderate non-proliferative diabetic retinopathy (NPDR), 51 eyes with severe NPDR, and 40 eyes with proliferative diabetic retinopathy (PDR) from 101 participants were included. The detection rates of microaneurysms (MAs), intraretinal microvascular abnormalities (IRMAs), and neovascularization (NV) for the 12 mm × 12 mm central and 24 mm × 20 mm images were comparable (p > 0.05). The detection rate of NPAs for the 24 mm × 20 mm image was 64.5%, which was significantly higher than that for the 12 mm × 12 mm central image (52.3%, p < 0.05). The average ischemic index (ISI) was 15.26% for the 12 mm~24mm-annulus, which was significantly higher than that for the 12 mm × 12 mm central image (5.62%). Six eyes had NV and 10 eyes had IRMAs that only existed in the 12 mm~24mm-annulus area. Conclusions: The newly developed high-speed ultra-widefield SS-OCTA can capture a 24 mm × 20 mm retinal vascular image during a single scan, which improves the accuracy of detecting the degree of retinal ischemia and detection rate of NV and IRMAs.

Comparison of the Biological Characteristics of Mesenchymal Stem Cells Derived from the Human Placenta and Umbilical Cord.

Mesenchymal stem/stromal cells (MSCs) derived from placental tissue show great therapeutic potential and have been used in medical treatment, but the similarity and differences between the MSCs derived from various parts of the placenta remain unclear. In this study, we compared MSCs derived from different perinatal tissues, including the umbilical cord (UC), amniotic membrane (AM), chorionic plate (CP) and decidua parietalis (DP). Using human leukocyte antigen (HLA) typing and karyotype analysis, we found that the first three cell types were derived from the foetus, while the MSCs from the decidua parietalis were derived from the maternal portion of the placental tissue. Our results indicate that both foetal and maternal MSCs share a similar phenotype and multi-lineage differentiation potential, but foetal MSCs show a significantly higher expansion capacity than do maternal MSCs. Furthermore, MSCs from all sources showed significant differences in the levels of several paracrine factors.

Protective effect of resveratrol against light-induced retinal degeneration in aged SAMP8 mice.

PURPOSE: The purpose of this study was to determine the protective effects of Resveratrol (RESV) on acute bright light-induced retinal degeneration in aged senescence accelerated mouse strain. METHODS: Ten three-month-old male SAMP8 mice (prone to aging) were randomly assigned to two experimental dietary groups: one untreated group and one RESV treatment group (n=20 eyes for each group). After 30 days of treatment, mice were exposed to intense bright light. Ten male SAMR1 mice (resistant to aging) served as control (n=20 eyes). The protective effects of RESV administration on light-induced retinal degeneration in SAMP8 strain as well as the effect of bright light damage in the retinas of SAMP8 mice were analyzed by electroretinography (ERG), retinal histology, mRNA, protein and lipid profile. RESULTS: 68%-85% of a-wave amplitude and 72%-92% of b-wave amplitude were persevered by RESV in SAMP8 mice that were exposed to light damage. Also, RESV preserved their photoreceptor nuclei. mRNA expression of neuroprotective factors leukemia inhibitory factor (LIF), brain derived neurotrophic factor (BDNF), oncostatin M (OSM), cardiotrophin 1(CT-1) and cardiotrophin-like cytokine (CLC) were up-regulated 28, 8, 7, 5 and 9-fold in SAMP8 mice after RESV treatment. In addition, RESV could suppress the NF-κB pathway by down-regulating the expression of pIκB. Light damage led to increase of saturated FA, monoenoic FA, n6 PUFA and n6/n3 ratio and decrease of Docosahexaenoic acid (DHA). There was no significant difference on DHA and the ratio of n6/n3-FA between the untreated and RESV treated SAMP8 mice. CONCLUSIONS: Collectively, our study provides evidence that RESV prevents light-induced retinal damage associated with aging.

The impact of miR-26b on retinal pigment epithelium cells in rhegmatogenous retinal detachment model.

Rhegmatogenous retinal detachment (RRD) is a type of blind eye disease that seriously affects the physical and mental health. The early pathological changes are closely related to the migration of retinal pigment epithelium (RPE) cells to the vitreous body. It was showed miR-26b plays an important role in regulating lens epithelial cell growth and proliferation. However, the expression and role of miR-26b in RPE from RRD is still unclear. Rabbit RRD model was established. RPE cells were isolated and cultivated. MiR-26b inhibitor was transfected to RPE cells from model group. MiR-26b expression was tested by Real-time PCR. RPE cell proliferation was evaluated by MTT assay. Ki-67 and PCNA expressions were detected by Western blot. Caspase 3 activity was measured by the kit. RPE cell invasion was determined by Transwell assay. MiR-26b significantly increased in RPE cells from model group. It obviously promoted RPE cell proliferation and invasion, suppressed Caspase 3 activity, and upregulated Ki-67 and PCNA expression compared with control (P < 0.05). MiR-26b inhibitor transfection markedly restrained RPE cell proliferation and invasion, enhanced Caspase 3 activity, and inhibited Ki-67 and PCNA levels compared with model group (P < 0.05). MiR-26b expression was upregulated in RRD. Downregulation of miR-26b can postpone the occurrence and development of RRD through inhibiting Ki-67 and PCNA, regulating cell apoptosis, and restraining RPE cell proliferation and invasion.