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Nicotinamide adenine dinucleotide (NAD+), a coenzyme that plays crucial roles in many cellular processes, is a potential therapeutic target for various diseases. Dihydronicotinamide riboside (NRH), a novel reduced form of nicotinamide riboside, has emerged as a potent NAD+ precursor. Here, we studied the protective effects and underlying mechanism of NRH on aminoglycoside-induced ototoxicity. Auditory function and hair-cell (HC) morphology were examined to assess the effects of NRH on kanamycin-induced hearing loss. The pharmacokinetic parameters of NRH were measured in plasma and the cochlea using liquid chromatography tandem mass spectrometry. NAD+ levels in organ explant cultures were assessed to compare NRH with known NAD+ precursors. Immunofluorescence analysis was performed to detect reactive oxygen species (ROS) and apoptosis. We analyzed SIRT1 and 14–3–3 protein expression. EX527 and resveratrol were used to investigate the role of SIRT1 in the protective effect of NRH against kanamycin-induced ototoxicity. NRH alleviated kanamycin-induced HC damage and attenuated hearing loss in mice. NRH reduced gentamicin-induced vestibular HC loss. Compared with NAD and NR, NRH produced more NAD+ in cochlear HCs and significantly ameliorated kanamycin-induced oxidative stress and apoptosis. NRH rescued the aminoglycoside-induced decreases in SIRT1 and 14–3–3 protein expression. Moreover, EX527 antagonized the protective effect of NRH on kanamycin-induced HC loss by inhibition of SIRT1, while resveratrol alleviated HC damage caused by EX527. NRH ameliorates aminoglycoside-induced ototoxicity by inhibiting HC apoptosis by activating SIRT1 and decreasing ROS. NRH is an effective therapeutic option for aminoglycoside-induced ototoxicity. • NRH effectively protects against aminoglycoside-induced ototoxicity. • NRH alleviates aminoglycoside-induced HC damage via SIRT1 activation. • NRH has superior ability to increase NAD+ in the cochlea than NR. [ABSTRACT FROM AUTHOR]

Highlights: [•] Surface fluorinated TiO2 (F–TiO2) had the remarkable activity for PCO of NH3. [•] Surface fluorination formed the surface Ti–F group. [•] Surface fluorination increased the reactive (001) facets percentage to about 50%. [•] Both Ti–F group and reactive (001) facets led to the high activity of F–TiO2. [•] Surface Ti–F group plays the dominant role in enhancing the PCO of NH3 activity. [Copyright &y& Elsevier]

Carbon-modified titanium dioxide (TiO 2 ) was prepared by a sol-gel method using tetrabutyl titanate as precursor, with calcination at various temperatures, and tested for the photocatalytic oxidation (PCO) of gaseous NH 3 under visible and UV light. The test results showed that no samples had visible light activity, while the TiO 2 calcined at 400°C had the best UV light activity among the series of catalysts, and was even much better than the commercial catalyst P25. The catalysts were then characterized by X-ray diffractometry, Brunauer-Emmett-Teller adsorption analysis, Raman spectroscopy, thermogravimetry/differential scanning calorimetry coupled with mass spectrometry, ultraviolet-visible diffuse reflectance spectra, photoluminescence spectroscopy and in situ diffuse reflectance infrared Fourier transform spectroscopy. It was shown that the carbon species residuals on the catalyst surfaces induced the visible light adsorption of the samples calcined in the low temperature range (< 300°C). However, the surface acid sites played a determining role in the PCO of NH 3 under visible and UV light over the series of catalysts. Although the samples calcined at low temperatures had very high SSA, good crystallinity, strong visible light absorption and also low PL emission intensity, they showed very low PCO activity due to their very low number of acid sites for NH 3 adsorption and activation. The TiO 2 sample calcined at 400°C contained the highest number of acid sites among the series of catalysts, therefore showing the highest performance for the PCO of NH 3 under UV light. [ABSTRACT FROM AUTHOR]

Highlights: [•] OMC with large surface area and open pore as active electrode material. [•] Highly selective determination of Tyr in the presence of CysH at physiological pH. [•] Wide linear range for Tyr from 15 to 900μM. [ABSTRACT FROM AUTHOR]

• Ti 3 C 2 T x MXene intercalated with yarn-ball-shaped microspheres for EMI shielding. • Yarn-ball-shaped microspheres provide more reflection interfaces in hybrid films. • Films with hierarchical structure are conducive causing more absorption of EMW. • The EMI shielding films exhibit excellent mechanical robustness and durability. Ti 3 C 2 T x MXenes with excellent metallic conductivity have proved promising in its application of electromagnetic interference (EMI) shielding. A hierarchical hybrid film with ultrathin thickness composed of Ti 3 C 2 T x MXene layers embedded with yarn-ball-shaped microspheres of cellulose nanofibrils (CNF) and multiwalled carbon nanotube (MWCNT) was designed to improve the absorption of electromagnetic waves (EMWs). The addition of yarn-ball-shaped microspheres is to shield more EMWs via multiple reflections in the inner space and reduce the undesirable emissions into the air. After thermal annealing treatment, the ultrathin film with intercalation of the carbonized yarn-ball-shaped CNF/MWCNT microspheres exhibited enhanced EMWs absorption as an important part of shielding effectiveness (45.1±0.9 dB) as well as excellent mechanical stability (≈0.9 million bending times). Thus, the well-designed structure of multilayered hybrid films with intercalated conductive microspheres can be a good candidate for higher absorption in EMI shielding effectiveness and outstanding mechanical properties. [ABSTRACT FROM AUTHOR]

Objectives: We aimed to evaluate gaps in noise (GIN) detection and visual analog scale (VAS) for measuring perceived tinnitus loudness and annoyance caused thereby. We quantified the outcomes and effectiveness of repetitive transcranial magnetic stimulation (rTMS) on chronic tinnitus.Methods: Fourteen tinnitus patients with normal hearing underwent a 10 day course of active 1-Hz rTMS to the left region of the temporoparietal cortex. GIN (in which the matched pitch and loudness of tinnitus was used to determine the frequency and intensity of background noise) and VAS was used to assess tinnitus loudness and the extent of annoyance caused thereby. Both ten patients with tinnitus who underwent left temporoparietal sham stimulation and fifteen volunteers with normal hearing without tinnitus participated with GIN detection as a control. Correlations between VAS scores and GIN detection were determined via Spearman's correlation analysis.Results: The mean GIN thresholds of tinnitus-affected (5.87 ms) ears and the ears of control subjects (4.85 ms) differed significantly. In the tinnitus group, 42.8% (6/14) patients experienced significant reductions in tinnitus annoyance, as assessed by VAS. 71.4% (10/14) patients experienced significant reductions in tinnitus loudness, as evidenced by GIN evaluation. Three tinnitus subjects (21.4%) achieved 30% decrease of the threshold of GIN detection. There was no significant change in GIN detection and VAS scores after sham stimulation. A significant positive correlation was evident between GIN data and VAS scores (r=0.84, p<0.001).Conclusions: Gaps in noise detection, combined with VAS scores, affords a promising sensitive method by which to evaluate tinnitus loudness and annoyance. Low frequency rTMS significantly decreased tinnitus after the active, but not the sham, treatment. [ABSTRACT FROM AUTHOR]

• The polyvinyl alcohol/ 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide derivative/two-dimensional (2D) MXene (PVA/DiDOPO/MXene) composite aerogel was prepared by ice template one-way freezing process. • PVA-DiDOPO4 composite aerogel with an oriented porous structure reaches the V-1 level at the UL-94 test. Moreover, the peak heat release rate (pHRR) value of PVA-DiDOPO4 reduces to 452.26 (W/g) from 482.88 (W/g) of pure PVA. • PVA/DiDOPO/MXene composite aerogel has improved thermal decomposition properties such as the maximum decomposition temperature (T max1) of the PVA-DiDOPO4 sample attains 319.92 °C from pure PVA of 302.90 °C. The fabrication of ultralight high-performance flame-retardant composites significantly reduces fire risk for buildings. Flame retardation of porous polyvinyl alcohol (PVA) aerogels with directional arrangement is difficult. Herein, the polyvinyl alcohol/ 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide derivative/two-dimensional (2D) MXene (PVA/DiDOPO/MXene) composite aerogel was prepared by ice template one-way freezing process. PVA-DiDOPO4 composite aerogel with an oriented porous structure reaches the V-1 level at the UL-94 test. Moreover, the peak heat release rate (pHRR) value of PVA-DiDOPO4 reduces to 452.26 (W/g) from 482.88 (W/g) of pure PVA. In addition, PVA/DiDOPO/MXene composite aerogel has improved thermal decomposition properties such as the maximum decomposition temperature (T max1) of the PVA-DiDOPO4 sample attains 319.92 °C from pure PVA of 302.90 °C. The design strategy of PVA combined 2D MXene nanosheet and DOPO derivatives construct oriented porous composite aerogel paves the way for the fabrication and customization of ultralight flame-retardant polymer composites, which can be expected to be applied in construction and reduce fire risk. [ABSTRACT FROM AUTHOR]

Abstract: Sirtuins maintain energy balance. Particularly, sirtuin 1 (SIRT1) activation mimics calorie restriction and nutrient utilization. However, no medications are available for the up-regulation of SIRT1. Methylene blue (MB) had been in clinical trials for the treatment of neurological diseases. This study investigated the effect of MB on sirtuin expression in association with the treatment of steatosis and steatohepatitis, and explored the underlying basis. The effects of MB on mitochondrial function, molecular markers, pharmacokinetics, and histopathology were assessed using hepatocyte and/or mouse models. Immunoblotting, PCR and reporter assays were done for molecular experiments. After oral administration, MB was well distributed in the liver. MB treatment increased NAD+/NADH ratio in hepatocytes. Of the major forms, MB treatment up-regulated SIRT1, and thereby decreased PGC-1α acetylation. Consistently, hepatic mitochondrial DNA contents and oxygen consumption rates were enhanced. MB treatment also notably activated AMPK, CPT-1 and PPARα: the AMPK activation relied on SIRT1. Activation of LXRα and the induction of SREBP-1c and its target genes by T0901317 were diminished by MB. In addition, MB treatment antagonized the ability of palmitate to acetylate PGC-1α, and increase SERBP-1c, FAS, and ACC levels. In mice fed on a high-fat diet for 8 weeks, MB treatment inhibited excessive hepatic fat accumulation and steatohepatitis. The ability of MB to activate SIRT1 promotes mitochondrial biogenesis and oxygen consumption and activates AMPK, contributing to anti-lipogenesis in the liver. Our results provide new information on the potential use of MB for the treatment of steatosis and steatohepatitis. [Copyright &y& Elsevier]

Although supplemental high-level oxygen treatment can promote the survival of premature infants, hyperoxia may adversely induce acute lung injury (ALI) in newborns. Our prior work illustrated that hyperoxic exposure could enhance the release of placental growth factor (PLGF) in the lungs of neonatal rats. We therefore postulated that PLGF contributed to hyperoxic ALI in newborns and evaluated the anti-PLGF treatment mediated by systematic delivery of lentivirus in hyperoxic ALI in this study. Lentivirus particles containing PLGF specific shRNA were injected into neonatal rats prior to hyperoxic exposure (90% oxygen for 72 h) to inhibit PLGF expression. Hyperoxia induced oxidative damages in lung tissues as evidenced by the increased malondialdehyde and myeloperoxidase, and the decreased antioxidant superoxide dismutase. Also, hyperoxia caused excessive infiltration of inflammatory cells and overproduction of proinflammatory cytokines (tumor necrosis factor-α, interleukin-1β and interleukin-6) in rat lung tissue. These pathological alterations were partly reversed by PLGF shRNA delivery. The expression levels and activities of metalloproteinase (MMP)-2 and MMP9 were up-regulated in response to hyperoxia, whereas down-regulated when PLGF was inhibited. Moreover, PLGF shRNA inhibited nuclear factor kappa B (NFκB) signaling delivery in hyperoxic rat lungs. Additionally, exogenous PLGF-induced activation of MMPs in rat RLE-6TN alveolar epithelial cells was suppressed by NFκB inhibitor pyrrolidine dithiocarbamate. These results suggest that therapy targeting PLGF may be beneficial for infants with hyperoxic ALI. [ABSTRACT FROM AUTHOR]

Aims To investigate the role of placenta growth factor (PLGF) in hyperoxia-induced lung injury in preterm born rats. Main methods Primary alveolar epithelial cells type II (AECIIs) were exposed to 90% oxygen for 24 h. Preterm born rats were delivered by caesarean section, injected with PLGF-shRNA, and exposed to 90% oxygen for 14 days. MTT was used to examine the viability of cells. ELISA was used to measure the secretion of PLGF in primary AECIIs and bronchoalveolar lavage fluid. Flow cytometry and TUNEL staining were used to measure cell apoptosis in the lung. Expression of PLGF mRNA was detected using real-time PCR, and protein expression of PLGF and apoptotic proteins was detected using Western blotting analysis. Immunofluorescence staining was used to measure the expression of E-cadherin and α-smooth muscle actin (α-SMA). Key findings Exogenous PLGF inhibited viability of AECIIs. In addition, treatment of PLGF increased the percentage of apoptotic cells, regulated the expression of E-cadherin and α-SMA in the primary AECIIs. Moreover, PLGF exacerbated these pathological changes in hyperoxia-exposed AECIIs. In the in vivo study, shRNA mediated PLGF inhibition attenuated lung injury induced by hyperoxia exposure. In addition, PLGF inhibition reduced the percentage of apoptotic cells, increased the expression of Bcl-2 and decreased expression of Bax and cleaved-caspase 3. PLGF inhibition also reduced collagen deposition and inhibited epithelial-to-mesenchymal transition (EMT) in the lung of hyperoxia-exposed rat pups. Significance Our findings suggested that PLGF contributed to hyperoxia-induced lung injury through promoting apoptosis and EMT. PLGF may become a therapeutic target of hyperoxia-induced lung injury. [ABSTRACT FROM AUTHOR]

• Surface metallization of cellulose nanofibrils obtained via electroless deposition. • Self-polymerization of polydopamine on CNFs surface acted as activation site. • CNFs@PDA@AgNPs films were assembled by pressured-extrusion process. • The composite films exhibited high conductivity and EMI shielding effectiveness. • The cellulose based EMI shielding films possessed excellent mechanical properties. High-efficient electromagnetic interference (EMI) shielding films were successfully fabricated by electroless deposition of silver nanoparticles (AgNPs) on polydopamine (PDA) functionalized cellulose nanofibrils (CNFs) as building blocks according to a pressured-extrusion film-forming process. PDA was first functionalized on CNFs by oxidative self-polymerization of dopamine (DA) to synthesize CNFs@PDA, on which AgNPs were electrolessly deposited. The obtained CNFs@PDA@AgNPs composite films served as tightly-connected conductive network, so as to significantly improve the whole electrical conductivity of the EMI shielding films. Utilizing CNFs as green and soft matrix, the fabricated CNFs@PDA@AgNPs EMI films show an outstanding mechanical enduring performance. The CNFs@PDA@AgNPs films with weight ratios of CNFs:AgNO 3 = 1:24 exhibited superb electrical conductivity of 1,000,000 S m−1 and remarkable EMI shielding effectiveness of 93.8 dB at 8.2 GHz in X band. This work provides a simple methodology to achieve surface metallization of insulating fibers to supersede traditional metals for highly efficient EMI shielding applications. [ABSTRACT FROM AUTHOR]

MnN 4 porphyrin-like graphene catalyzed ethylene epoxidation to selectively produce ethylene oxide by using N 2 O as oxidizing agent. • High selective catalyst was proposed for ethylene epoxidation to ethylene oxide. • Reaction mechanism was investigated by dispersion corrected DFT calculation. • Nitrous oxide which is toxic gas was a good oxidizing agent for the reaction. • The reaction rate for ethylene oxide production is 104 times faster than acetaldehyde. Ethylene epoxidation to produce ethylene oxide is crucial in both fundamental knowledge and industrial chemical process. The reaction mechanism of ethylene epoxidation with N 2 O catalyzed by Mn-coordinated porphyrin-like graphene (Mn-N 4 GP) was investigated using dispersion-corrected density functional theory calculations. The reaction proceeds through two consecutive steps, (1) Mn O active site (MnO-N 4 GP) formation, followed by (2) ethylene epoxidation on the Mn O. The first step is a feasible process with the energy barrier of 0.77 eV and the MnO-N 4 GP is thermodynamically stable. The ethylene epoxidation in the second step competitively can undergo three possible intermediate-pathways; carboradical, alkoxide radical, and manganaoxetane intermediates. By systematic study of all possible pathways, we found that the pathway for alkoxide radical intermediate shows the most feasibility which it subsequently converts to three competitive products with the energy barriers of 0.25 eV, 0.56 eV, and 0.46 eV for the formation of ethylene oxide, acetaldehyde, and 5-membered ring (5MR) species, respectively. This catalyst is remarkably selective to ethylene oxide by 105 and 104 times compared with acetaldehyde and 5MR side products, respectively. Thus, the Mn-N 4 GP catalyst is suggested as a promising catalyst in terms of activity and selectivity for ethylene epoxidation using N 2 O as an oxidizing agent in mild condition. [ABSTRACT FROM AUTHOR]