Strong Electronic Interaction in High-Entropy Oxide Enhances Oxygen Evolution Reaction.

High-entropy oxides are a new type of material with significant application potential. However, the lack of a universal HEO preparation method severely limits the property study and application of HEOs. Herein, we report a universal approach of spray pyrolysis for the preparation of various HEOs and study the electrocatalytic performance of HEOs toward the oxygen evolution reaction. FeCoNiMoWOx HEO exhibits an overpotential of 281 mV at 10 mA cm-2 and a Tafel slope of 34.5 mV dec-1, which are far superior to those of the corresponding medium-entropy oxide and low-entropy oxide. It is found that the high entropy of the HEO greatly strengthens the interaction between Fe and Mo/W and produces abundant oxygen vacancies (OVs) around Mo and W. This work not only provides a universal preparation method for HEOs but also deepens our understanding of OER catalytic activity of HEOs.

Unveiling the Effect of Organic Sulfur Sources on Synthesized MoS2 Phases and Electrocatalytic Hydrogen Evolution Performances.

Metallic-phase MoS2 exhibits Pt-comparable electrocatalytic hydrogen evolution reaction (HER) performance in acidic conditions. However, the controllable synthesis of metallic-phase MoS2 is quite challenging because the key factor determining the phase types of MoS2 during synthesis is still unclear. Herein, the effect of organic sulfur sources on the formed MoS2 phase is studied by use of thioacetamide (TAA), l-cysteine, and thiourea as sulfur sources. The TAA and l-cysteine produce metallic MoS2, while thiourea gives rise to semiconducting MoS2. Owing to the metallic phase and smaller size, the MoS2 prepared with TAA and l-cysteine has a higher electrocatalytic HER activity than the MoS2 obtained from thiourea. The HER overpotential of MoS2 synthesized with TAA is only 210 mV for reaching the current density of 10 mA/cm2, and the corresponding Tafel slope is 44 mV/decade. Further studies find that the decomposition temperature of sulfur precursors is the key factor for the formation of metallic MoS2. Sulfur precursors with a lower decomposition temperature release sulfur ions quickly, which in turn stabilize the metallic phase and inhibit the growth of MoS2 into large sizes. Our findings unveil the key factor for controlling the phase type of MoS2 synthesized from organic sulfur precursors and will be very helpful for the synthesis of MoS2 with high electrocatalytic activity.

Efficacy of vitamin and antioxidant supplements for treatment of diabetic peripheral neuropathy: systematic review and meta-analysis of randomized controlled trials.

ABSTRACTThe results of treatment effect of vitamin or antioxidant intake on diabetic peripheral neuropathy (DPN) was inconsistent. Therefore, we performed a meta-analysis of randomized controlled trials (RCTs) to examine whether these supplements are effective in DPN treatment. We searched seven databases from inception to October 2021. All RCTs of DPN treatments with vitamin and antioxidant supplements were included. We performed sensitivity and subgroup analysis, and also tested for publication bias by the funnel plot and Egger's test. A total of 14 studies with 1384 patients were included in this systematic review. Three high-quality trials showed that vitamin and antioxidant supplements significantly increased sensory nerve conduction velocity (SNCV) of the sural nerve (MD = 2.66, 95%CI (0.60, 4.72), P < 0.05, I2 = 0%). Seven studies (758 participants) suggested that these supplements might have improvement on motor nerve conduction velocity (MNCV) of the peroneal nerve in DPN patients with the random-effect model (MD = 0.60, 95%CI (0.28, 0.92), P < 0.05, I2 = 65%). In four studies, these supplements could have improved on MNCV of the median nerve with the fixed-effect model (MD = 4.22, 95%CI (2.86, 5.57), P < 0.05, I2 = 0%). However, ten studies (841 participants) have suggested that vitamin and antioxidant supplements have not decreased glycosylated haemoglobin (HbA1c). Vitamin and antioxidant supplements may improve the conduction velocity of nerves, including median, sural and peroneal nerves of patients with DPN. But these supplements have not decreased HbA1c in DPN patients. Several trials with a large sample size are needed to provide evidence support for clinical practice in the future.

Protective Effect of Lycium ruthenicum Polyphenols on Oxidative Stress against Acrylamide Induced Liver Injury in Rats.

Acrylamide (ACR) is formed during tobacco and carbohydrate-rich food heating and is widely applied in many industries, with a range of toxic effects. The antioxidant properties of Lycium ruthenicum polyphenols (LRP) have been established before. This study aimed to research the protective effect of LRP against ACR-induced liver injury in SD rats. Rats were divided into six groups: Control, ACR (40 mg/kg/day, i.g.), LRP (50, 100, and 200 mg/kg/day, i.g.) plus ACR, and LRP groups. After 19 days, we evaluated oxidative status and mitochondrial functions in the rat's liver. The results showed that glutathione (GSH) and superoxide dismutase (SOD) levels increased after LRP pretreatment. In contrast, each intervention group reduced reactive oxygen species (ROS) and malondialdehyde (MDA) levels compared to the ACR group. Meanwhile, alanine aminotransferase (ALT), aspartate aminotransferase (AST), liver mitochondrial ATPase activity, mRNA expression of mitochondrial complex I, III, and expression of nuclear factor-erythroid 2-related factor 2 (Nrf2) and its downstream proteins were all increased. This study suggested that LRP could reduce ACR-induced liver injury through potent antioxidant activity. LRP is recommended as oxidative stress reliever against hepatotoxicity.

Efficacy and safety of computer-assisted stereotactic transplantation of human retinal pigment epithelium cells in the treatment of Parkinson disease.

OBJECTIVE: This study explores the efficacy and safety of computer-assisted stereotactic transplantation of human retinal pigment epithelium (hRPE) cells in the treatment of Parkinson disease (PD). METHODS: Guided by computed tomography and magnetic resonance imaging image mergence, we transplanted 4 × 10 hRPE cells into the putamina and lateral ventricles of 17 PD cases by stereotactic surgery. The transplantation site was located in the contralateral side of the symptoms and signs. RESULTS: At 3 months after operation, the effective rates of cell transplantation were 82.4% in the contralateral site and 64.7% in the ipsilateral site. Minority of the cases had mild dizziness and hemiparesis, but the durations were short. CONCLUSIONS: Computer-assisted stereotactic transplantation of hRPE for the treatment of PD is safe and efficient.

Dietary exposure to acrylamide of university students in Ningxia of Northwest China and the effect on their neurobehavioral performance and oxidative stress in serum.

This study aims to investigate dietary exposure to acrylamide (AA) and also make an assessment of its effect on the neurobehavioral performance and oxidative stress in the serum of university students in Ningxia. The place primarily consists of arid, dry desert, and wheat-based foods are the staple food there. A total of 803 university students in Ningxia participated in this cross-sectional study. Diet intake of AA was estimated with FFQ. The AA risk was calculated as margin of exposure (MOE) values. NCTB questionnaires were used to assess neurobehavioral performance. The serum oxidative stress levels of the university students were measured as GSH, MDA, and SOD. The mean for AA exposure of university students was 0.515 µg kg-1 bw day-1. The highest contributor was traditional Chinese grain products, representing 34.71% of the total daily AA intake. Followed were deep-fried potato products, traditional Western grain products, soft drinks, and nuts, which accounted for 23.87%, 16.59%, 11.15%, and 11%, respectively. The median AA exposure were 480 (BMDL10 = 0.18 mg kg-1 bw day-1) and 827 (BMDL10 = 0.31 mg kg-1 bw day-1), respectively. The results indicated that diet AA may have an effect on the emotional status and neurobehavior among this population. We observed no significant differences in oxidative stress under the three levels of AA exposure (p > .05). It suggests a health concern for university students in Northwest China that should get society's attention.

Protective effect and mechanism of Lycium ruthenicum polyphenols against acrylamide-induced neurotoxicity.

This study aimed to investigate the potential neuroprotective effects of Lycium ruthenicum polyphenols (LRP) against acrylamide (ACR)-induced neurotoxicity and the mechanism of action in vitro and in vivo. LRP treatment significantly attenuated ACR-induced cytotoxicity in SH-SY5Y cells in a dose-dependent manner. LRP treatment increased the nuclear factor erythroid-2-related factor 2 (Nrf2) protein and subsequent activation of downstream proteins in SH-SY5Y cells. LRP treatment down-regulated the expression of relevant apoptotic proteins, including JNK, P-JNK, P38, P-P38, and caspase 3 in ACR-induced cells. In vivo, LRP improved exploratory and locomotor deficits in ACR-induced rats. LRP activated the Nrf2 pathway in the striatum and substantia nigra. LRP treatment attenuated striatal ROS levels and increased GSH and SOD in ACR-induced rats. Immunohistochemistry, western blot, and ELISA revealed a significant increase in tyrosine hydroxylase (TH) neurons and dopamine and its metabolites in the striatum and substantia nigra under the protective effect of LRP. Therefore, LRP can be a protective agent against ACR-induced brain damage.

Atomically Dispersed Fe-N4 Sites and NiFe-LDH Sub-Nanoclusters as an Excellent Air Cathode for Rechargeable Zinc-Air Batteries.

The sluggish four-electron processes of the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) limit the development of rechargeable Zn-air batteries (RZABs). Highly efficient ORR/OER bifunctional electrocatalysts are therefore highly desired for the commercialization of RZABs in large scale. Herein, the Fe-N4-C (ORR active sites) and NiFe-LDH clusters (OER active sites) are successfully integrated within a NiFe-LDH/Fe,N-CB electrocatalyst. The NiFe-LDH/Fe,N-CB electrocatalyst is first prepared by the introduction of Fe-N4 into carbon black (CB), followed by the growth of NiFe-LDH clusters. The cluster nature of NiFe-LDH effectively avoids the blocking of Fe-N4-C ORR active centers and affords excellent OER activity. The NiFe-LDH/Fe,N-CB electrocatalyst thus exhibits an excellent bifunctional ORR and OER performance, with a potential gap of only 0.71 V. The NiFe-LDH/Fe,N-CB-based RZAB exhibits an open-circuit voltage of 1.565 V and a specific capacity of 731 mAh gZn-1, which is much better than the RZAB composed of Pt/C and IrO2. Particularly, the NiFe-LDH/Fe,N-CB-based RZAB displays excellent long-term charging/discharging cyclic stability and rechargeability. Even at a large charging/discharging current density (20 mA cm-2), the charging/discharging voltage gap is only ∼1.33 V and exhibits an increase smaller than 5% after 140 cycles. This work provides a new low-cost bifunctional ORR/OER electrocatalyst with high activity and superior long-term stability and will be helpful to the commercialization of RZAB in large scale.

Germacrone alleviates neurological deficits following traumatic brain injury by modulating neuroinflammation and oxidative stress.

BACKGROUND: Germacrone (GM) is a terpenoid compound which is reported to have anti-inflammatory and anti-oxidative effects. However, its role in treating traumatic brain injury (TBI) remains largely unknown. METHODS: Male C57BL/6 mice were divided into the following groups: control group, TBI group [controlled cortical impact (CCI) model], CCI + 5 mg/kg GM group, CCI + 10 mg/kg GM group and CCI + 20 mg/kg GM group. GM was administered via intraperitoneal injection. The neurological functions (including motor coordination, spatial learning and memory abilities) and brain edema were measured. Nissl staining was used to detect the neuronal apoptosis. Colorimetric assays and enzyme linked immunosorbent assay (ELISA) kits were used to determine the expression levels of oxidative stress markers including myeloperoxidase (MPO), malondialdehyde (MDA) and superoxide dismutase (SOD), as well as the expressions of inflammatory markers, including tumor necrosis factor α (TNF-α), interleukin-1ß (IL-1ß) and interleukin-6 (IL-6). Additionally, protein levels of Nrf2 and p-p65 were detected by Western blot assay. RESULTS: GM significantly ameliorated motor dysfunction, spatial learning and memory deficits of the mice induced by TBI and it also reduced neuronal apoptosis and microglial activation in a dose-dependent manner. Besides, GM treatment reduced neuroinflammation and oxidative stress compared to those in the CCI group in a dose-dependent manner. Furthermore, GM up-regulated the expression of antioxidant protein Nrf2 and inhibited the expression of inflammatory response protein p-p65. CONCLUSIONS: GM is a promising drug to improve the functional recovery after TBI via repressing neuroinflammation and oxidative stress.

(Fe,N-codoped carbon nanotube)/(Fe-based nanoparticle) nanohybrid derived from Fe-doped g-C3N4: A superior catalyst for oxygen reduction reaction.

Transition metal- and N-codoped carbon nanotubes (CNTs) have superior catalytic activity because the curling surface enhances the bonding ability of atoms within CNTs to other species. However, it is a great challenge to prepare CNTs with transition metal- and N-doped at high level during the growth of CNTs. Here, (Fe,N-codoped CNT)/(Fe-based nanoparticle) (Fe,N-CNT/FeNP) hybrid nanostructures are for the first time prepared through the carbonization of Fe-doped g-C3N4. The doping of Fe and N is simultaneously realized during the formation of CNTs. Meanwhile, the abundant and homogeneous Fe and N in Fe-doped g-C3N4 ensure high-level and uniform doping of Fe and N in CNTs. The Fe,N-CNT/FeNP hybrid nanostructures have several types of active components, including homogeneously distributed coordinating Fe moieties (FeCxNy or FeNx) and CFe15.1 nanoparticles embedded in Fe,N-CNTs, towards oxygen reduction reaction (ORR). A superior ORR electrocatalytic performance is therefore obtained on the Fe,N-CNT/FeNP nanohybrids. Our preparation method opens an avenue to preparation of CNTs with transition metal- and N-doping at high-level, and the superior performance of Fe,N-CNT/FeNP nanostructures for ORR will be very helpful to the development of fuel cells and metal-air batteries.