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Triboelectric nanogenerator (TENG) and piezoelectric nanogenerator (PENG) present excellent performances in harvesting multivariant mechanical energy. However, the conductivity of electrode has become one of the important factors restricting the mechanical energy acquisition under the large deformation and multiple freedom degrees. In this work, a highly conductive stretchable electrode based piezoelectric-enhanced triboelectric nanogenerator (P-TENG) with outstanding performance is reported. Ultra-flexible silicone rubber based triboelectric part with surface modification and piezoelectric part with BaTiO3 dispersed possess excellent electrical and mechanical property, at the same time, the stretchable electrode based on liquid metal could maintain low resistance even under large deformation. The peak to peak open-circuit voltage (VOC) and short-circuit current (ISC) of P-TENG could reach 1.38 kV and 36.13 μA, respectively. The instantaneous power density can reach 1.1 mW/cm2 and the charge quantity in single capacitor charging circle is approximately 0.30 μC. It also has the surpassing force-electrical linearity that the output voltage positively correlating to stretching speeds and stretching rates. The resistance increments of electrode below 0.32 Ω under stretching rate more than 200% and the percentage of breaking elongation could reach 645%. In applying experiments, the P-TENG could directly light 16 LEDs and effectively identify the motion signals. This work provides a new thought for nanogenerator (NG) with high stretchability and applied to collect irregular mechanical energy.

The neural functions of adropin, a secreted peptide highly expressed in the brain, have not been investigated. In humans, adropin is highly expressed in astrocytes and peaks during critical postnatal periods of brain development. Gene enrichment analysis of transcripts correlating with adropin expression suggests processes relevant to aging-related neurodegenerative diseases that vary with age and dementia state, possibly indicating survivor bias. In people aged 75 y) diagnosed with dementia, adropin correlates positively with genes involved in mitochondrial processes. In the ‘old-old’ without dementia adropin expression correlates positively with morphogenesis and synapse function. Potent neurotrophic responses in primary cultured neurons are consistent with adropin supporting the development and function of neural networks. Adropin expression in the ‘old-old’ also correlates positively with protein markers of tau-related neuropathologies and inflammation, particularly in those without dementia. How variation in brain adropin expression affects neurological aging was investigated using old (18-month) C57BL/6J mice. In mice adropin is expressed in neurons, oligodendrocyte progenitor cells, oligodendrocytes, and microglia and shows correlative relationships with groups of genes involved in neurodegeneration and cellular metabolism. Increasing adropin expression using transgenesis improved spatial learning and memory, novel object recognition, resilience to exposure to new environments, and reduced mRNA markers of inflammation in old mice. Treatment with synthetic adropin peptide also reversed age-related declines in cognitive functions and affected expression of genes involved in morphogenesis and cellular metabolism. Collectively, these results establish a link between adropin expression and neural energy metabolism and indicate a potential therapy against neurological aging.

SUMMARYDiabetes is associated with increased mortality from Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2). Given literature suggesting a potential association between SARS-CoV-2 infection and diabetes induction, we examined pancreatic expression of the key molecule for SARS-CoV-2 infection of cells, angiotensin-converting enzyme-2 (ACE2). Specifically, we analyzed five public scRNAseq pancreas datasets and performed fluorescencein situhybridization, Western blotting, and immunolocalization for ACE2 with extensive reagent validation on normal human pancreatic tissues across the lifespan, as well as those from coronavirus disease 2019 (COVID-19) patients. Thesein silicoandex vivoanalyses demonstrated pancreatic expression of ACE2 is prominent in pancreatic ductal epithelium and the microvasculature, with rare endocrine cell expression of this molecule. Pancreata from COVID-19 patients demonstrated multiple thrombotic lesions with SARS-CoV-2 nucleocapsid protein expression primarily limited to ducts. SARS-CoV-2 infection of pancreatic endocrine cells, via ACE2, appears an unlikely central pathogenic feature of COVID-19 as it relates to diabetes.

Cyclooxygenase (COX)-2 and matrix metalloproteinase (MMP)-9 are two crucial mediators contributing to blood-brain barrier (BBB) damage during cerebral ischemia. However, it is not known whether MMP-9 activation is involved in COX-2-mediated BBB disruption in ischemic stroke. In this study, we hypothesized that genetic deletion or pharmacological inhibition of COX-2 reduces BBB damage by reducing MMP-9 activity in a mouse model of ischemic stroke. Male COX-2 knockout (COX-2−/−) and wild-type (WT) mice were subjected to 60 min of middle cerebral artery occlusion (MCAO) followed by 24 h of reperfusion. Genetic deletion of COX-2 or post-ischemic treatment with CAY10404, a highly selective COX-2 inhibitor, significantly reduced BBB damage and hemorrhagic transformation, as assessed by immunoglobulin G (IgG) extravasation and brain hemoglobin (Hb) levels, respectively. Immunoblotting analysis showed that tight junction proteins (TJPs) zonula occludens (ZO)-1 and occludin as well as junctional adhesion molecule-A (JAM-A) and the basal lamina protein collagen IV were dramatically reduced in the ischemic brain. Stroke-induced loss of these BBB structural proteins was significantly attenuated in COX-2−/− mice. Similarly, stroke-induced loss of ZO-1 and occludin was significantly attenuated by CAY10404 treatment. Ischemia-induced increase in MMP-9 protein levels in the ipsilateral cerebral cortex was significantly reduced in COX-2−/− mice. Stroke induced a dramatic increase in MMP-9 enzymatic activity in the ischemic cortex, which was markedly reduced by COX-2 gene deficiency or pharmacological inhibition with CAY10404. Levels of myeloperoxidase (MPO, an indicator of neutrophil infiltration into the brain parenchyma), neutrophil elastase (NE), and lipocalin-2 (LCN2, also known as neutrophil gelatinase-associated lipocalin), measured by western blot and specific ELISA kits, respectively, were markedly increased in the ischemic brain. Increased levels of markers for neutrophil infiltration were significantly reduced in COX-2−/− mice compared with WT controls following stroke. Altogether, neurovascular protective effects of COX-2 blockade are associated with reduced BBB damage, MMP-9 expression/activity and neutrophil infiltration. Our study shows for the first time that MMP-9 is an important downstream effector contributing to COX-2-mediated neurovascular damage in ischemic stroke. Targeting the COX-2/MMP-9 pathway could represent a promising strategy to reduce neuroinflammatory events in order to preserve the BBB integrity and ameliorate ischemic stroke injury.

A new composite photocatalyst, ZnO/CoPzS8, was obtained by immobilizing cobalt tetra(2,3-bis(butylthio)maleonitrile)porphyrazine (CoPzS8) onto the surface of home-prepared ZnO. The ZnO/CoPzS8 composite was well characterized by X-ray diffraction (XRD), UV-vis diffuse reflectance spectroscopy (DRS), X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy. It turned out that CoPzS8 was successfully loaded onto the ZnO surface and there existed an interaction between ZnO and CoPzS8. By using the ZnO/CoPzS8 composite photocatalyst, the photocatalytic oxidation of glucose to value-added chemicals in pure water was conducted under simulated sunlight irradiation without adding any acid or base. The ZnO/CoPzS8 composite exhibited a higher photocatalytic activity in comparison to pure ZnO and pure CoPzS8 owing to the synergistic effect between ZnO and CoPzS8. Gluconic acid, arabinose, glycerol and formic acid were all observed as oxidation products when pure ZnO or ZnO/CoPzS8 composite was used. More importantly, glucaric acid was also obtained in the ZnO/CoPzS8 photocatalytic system, indicating that the presence of CoPzS8 changed the glucose reaction pathway. In addition, the active species generated in the photocatalytic process were further identified by electron spin resonance (ESR) technology and scavenger experiments. A possible photocatalytic conversion pathway of glucose has been proposed according to the experimental results.

The selective conversion of glucose into value-added chemicals in the presence of only water is a challenging topic. In this work, selective photocatalytic oxidation of glucose in water was studied using iron thioporphyrazine modified SnO2 (SnO2/FePz(SBu)8) as the catalyst and atmospheric air as the oxidant under simulated sunlight irradiation. It was found that value-added organic acids including glucaric acid, gluconic acid and formic acid could be obtained from the oxidation of glucose under such conditions. The effects of the FePz(SBu)8 content, glucose concentration and additional addition on the conversion of glucose and the selectivity of the organic acids were further explored. Under the optimized conditions, the total selectivity for the organic acids on the SnO2/FePz(SBu)8 photocatalyst reached up to 52.2% at 34.2% glucose conversion. More importantly, it has been demonstrated that the presence of FePz(SBu)8 on the surface of SnO2 can keep the selectivity of the organic acids unchanged under conditions of increasing the glucose conversion. To illustrate the synergistic effect for the enhanced photocatalytic activity between FePz(SBu)8 and SnO2, surface photocurrent, electron spin resonance (ESR) spectra and adsorption behavior experiments were carried out on pure SnO2 and SnO2/FePz(SBu)8. It was found that the introduction of FePz(SBu)8 could enhance the separation of photogenerated charge, promote the generation of active species for photocatalysis and improve the adsorption capacity of glucose, which are beneficial to the enhancement of photocatalytic activity. Additionally, a possible pathway of glucose oxidation was proposed through both detailed analysis of the oxidation intermediate of glucose and comparative experiments with different organic acids as the substrates, indicating that the formation of organic acids were fulfilled by two parallel and subsequent reactions at the beginning of the reaction.

Adropin is an endogenous peptide highly expressed in the brain and is encoded by the energy homeostasis-associated gene, Enho . We recently found that treatment with synthetic adropin peptide reduces infarct volume in ischemic stroke. This protection by exogenous adropin is associated with a significant increase in endothelial nitric oxide synthase (eNOS) phosphorylation (Ser 1176 ) and reduction of blood-brain barrier (BBB) permeability. However, it is not known whether endogenous adropin modulates ischemic brain damage. We hypothesize that lack of brain adropin increases stroke damage by exacerbating neurovascular dysfunction, while overexpression of this peptide decreases ischemic brain injury. We measured infarct size and BBB damage in male and female adropin overexpressing transgenics (AdrTg), adropin knockout ( Enho -/- ), and corresponding wild-type (WT) control mice subjected to permanent middle cerebral artery occlusion (pMCAO). At 48h after stroke, infarct volume was significantly smaller in AdrTg mice of both sexes compared to WT controls, while stroke resulted in a much larger infarction in both male and female Enho -/- compared to Enho +/+ mice. Brain levels of IgG and albumin, two sensitive markers of BBB disruption, were significantly reduced in AdrTg mice compared to the WT group, while the levels of these two plasma proteins in the ischemic brain of Enho -/- mice were dramatically increased compared to Enho +/+ animals after stroke. Latex vessel casting showed no differences in cerebrovascular anatomy or the diameter of the main brain arteries between Enho -/- , AdrTg and their respective WT controls. In AdrTg mice, we found a positive correlation between brain adropin levels and eNOS phosphorylation. These data suggest that increased eNOS phosphorylation by adropin is a potential mechanism underlying its protective effects in stroke. Consistent with this hypothesis, the protective effects of adropin were completely abolished in eNOS knockout (eNOS -/- ) mice subjected to pMCAO. Taken together, our findings show for the first time that endogenous adropin is a neuroprotective peptide in ischemic stroke. Understanding adropin signaling and function could offer a novel therapeutic strategy for the treatment of ischemic brain damage.

A novel strategy for the synthesis of zinc thioporphyrazine nanospheres is presented. The uniform spheres were fabricated through a polymerization reaction without using any template or emulsifier, which result from the covalent links between zinc tetra(2,3-bis(pentenylthio)porphyrazine (ZnPz) possessing eight long flexible chains in periphery and each with one terminal olefin group. A possible mechanism to explain the self-assembly of ZnPz nanospheres was also illuminated through monitoring nanosphere formation by means of transmission electron microscopy (TEM). More importantly, ZnPz nanospheres can effectively activate dioxygen in aqueous media under simulated sunlight irradiation, and showed significantly improved photocatalytic activity for the degradation of Rhodamine B (RhB) as compared to monomeric ZnPz. Furthermore, the reactive oxygen species derived from ZnPz nanospheres under light irradiation were determined by electron paramagnetic resonance (EPR) technology, indicating that singlet oxygen ([Formula: see text]O[Formula: see text] and hydroxyl radical (•OH) are the major reactive oxygen species. The facile synthetic methodology and the enhanced photocatalytic performance of the ZnPz nanospheres endow this novel material with the potential of being an efficient biomimetic photocatalyst for wastewater treatment.

Calibration accuracy validation (CAV) can usually be realized by intercalibration between different satellites. Under the framework of Global Space-Based Intercalibration System (GSICS), two modifications, improved spatial collocation with variable weighting (VW) and parallax correction (PC) approaches, to enhance the CAV performance are proposed. Distinguished from the uniform weighting method recommended by GSICS, the proposed VW one establishes a novel way of overlapping identification and overlapping area computation that is widely suitable for measurements from both the same and different platforms. Simulations indicate that the uncertainty of the VW method behaves better for the collocated targets far away from satellite’s nadir with a certain geolocation error, and is superior to 0.6 K for most overlapping situations when the geolocation error is less than 0.5 pixels. Case application shows that the VW method can significantly alleviate the uncertainty of assessed biases in brightness temperature (BT) by around 0.1–0.3 K for target nonuniformity larger than 2.5%, where the optimal bias estimation can be implemented with its uncertainty as little as possible. Besides the uncertainty improvement, the PC approach has the capability to reduce the bias of CAV by around 0.2–0.3 K, especially for BT range lower than 220 K with a limited number of paired samples. Long-term results show that the monthly biases of FY-2E and FY-2G satellites were superior to 1.5 and 1.0 K, respectively, where the mean monthly absolute biases of FY-2G IR1-IR3 bands were 0.4, 0.6, and 0.5 K, respectively. The proposed VW and PC methods are recommended for GSICS utilization and will further benefit to a more comprehensive community.

A highly efficient oxidation of amines including primary and secondary amines into imines using O2 as the oxidant was realized by cobalt tetra(2-hydroxymethyl-1,4-dithiin)porphyrazine (CoPz(hmdtn)4) under irradiation of visible light (λ ≥ 420 nm). Particularly, the photocatalytic selective oxidation of benzylamine into N-benzylidenebenzylamine was thoroughly studied in order to get more insight into the reaction kinetics and mechanism for the oxidation of amine. The photocatalytic oxidation of benzylamine was observed to follow pseudo-first-order reaction kinetics. Moreover, a reasonable linear relationship between the log(kX/kH) values and the Brown-Okamoto constant (σ+) parameters was obtained for oxidation of para- and meta-substituted benzylamines. Besides imine, the presence of other intermediate products such as NH-imine and H2O2 was further evidenced in this photocatalytic system. Additionally, the reactive oxygen species (ROSs) generated in this photocatalytic process were confirmed by electron spin resonance (ESR) technique. The possible photocatalytic transformation pathway of amine into imine was also proposed, involving the dehydrogenation of amine to form NH-imine and the nucleophilic addition of NH-imine by free amine to afford the final imine.

Textile-based triboelectric nanogenerators (T-TENGs) have been favorable devices to harvest human motion energy because of their excellent flexibility and high efficiency at low frequency. However, T-TENGs integrated with the conventional composite electrodes will suffer serious degradation on conductivity under stretching state. Herein, an omnidirectional stretchable triboelectric textile based on liquid metal (LM) electrodes has been proposed. By virtue of the excellent liquidity of LM and high stretchability of Ecoflex film, the triboelectric textile shows an ultimate elongation of 660% and maintains a small resistance (0.678 Ω) under 200% stretching. Additionally, by introducing TiO2 particles into the Ecoflex to improve the dielectric constant, the triboelectric textile obtained a ∼ 40% growth on short-circuit current and generated a high peak-peak power density of 15.4 W/m2 at 3 Hz and 30 N. Based on the excellent output performance, the triboelectric textile can continuously drive low-power electronics under palm flapping, ensuring the feasibility for energy harvesting from human motion.

A novel planar binuclear zinc hexa(2,3-bis(butylthio)) porphyrazine (bi-ZnPz(SBu)6) sharing one benzene ring has been synthesized. In order to assess the photocatalytic activity of bi-ZnPz(SBu)6, it was loaded on neutral Al2O3 to form a composite photocatalyst bi-ZnPz(SBu)6@Al2O3, then the degradation of rhodamine B (RhB) in an aerated suspension under simulated sunlight was carried out. It was discovered that the photocatalytic activity of bi-ZnPz(SBu)6 is two times higher than that of its mononuclear counterpart. A possible mechanism was proposed through theoretical calculation by density functional theory (DFT) and detection of reactive oxygen species by electron spin resonance (ESR) technology. The results show that the HOMO–LUMO energy gap (ΔEH–L) of bi-ZnPz(SBu)6 is much smaller than that of its mononuclear counterpart, which is beneficial to the excitation of energy and electron under irradiation of light. Super-powerful signals of singlet oxygen (1O2) formed by bi-ZnPz(SBu)6 indicated that the energy transfer capacity of bi-ZnPz(SBu)6 was enhanced significantly under irradiation of light while the electron transfer capacity was decreased due to the weakening of the contribution from the active S atoms in the thiobutyl groups in the periphery to the HOMO. This work introduces a novel and promising biomimetic antenna molecule, whose excellent light-harvesting capacity will be favored and admired in the field of solar cells, photocatalysis and photodynamic therapy.

Selective oxidation of 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA) is one of the key reactions for producing chemical commodities from biomass and their derivatives. The challenge for this reaction is to develop an efficient catalytic process that can be conducted under mild conditions (room temperature and atmospheric pressure, using oxygen molecules in air as the oxidant) and a recyclable catalyst. Herein we report a photocatalyst of cobalt thioporphyrazine (CoPz) dispersed on g-C3N4 (abbreviated as CoPz/g-C3N4), which exhibits excellent catalytic activity toward the selective oxidation of HMF into FDCA under simulated sunlight using oxygen molecules in air as a benign oxidant. For example, an FDCA yield of 96.1% in an aqueous solution at pH = 9.18 is achieved at ambient temperature and air pressure. At lower pH (4.01), the product generated is 2,5-diformylfuran. Hence, it is possible to control the reaction outcome by control of the pH of the reaction system. g-C3N4 itself is not...

In this study we propose the combination of topside in-situ ion density data from the Communication/Navigation Outage Forecast System (C/NOFS) along with the electron density profile measurement from Constellation Observing System for Meteorology, Ionosphere & Climate (COSMIC) satellites Radio Occultation (RO) for studying the spatial and temporal variations of the ionospheric upper transition height ( h T ) and the oxygen ion (O + ) density scale height. The latitudinal, local time and seasonal distributions of upper transition height show more consistency between h T re-calculated by the profile of the O + using an α-Chapman function with linearly variable scale height and that determined from direct in-situ ion composition measurements, than with constant scale height and only the COSMIC data. The discrepancy in the values of h T between the C/NOFS measurement and that derived by the combination of COSMIC and C/NOFS satellites observations with variable scale height turns larger as the solar activity decreases, which suggests that the photochemistry and the electrodynamics of the equatorial ionosphere during the extreme solar minimum period produce abnormal structures in the vertical plasma distribution. The diurnal variation of scale heights ( H m ) exhibits a minimum after sunrise and a maximum around noon near the geomagnetic equator. Further, the values of H m exhibit a maximum in the summer hemisphere during daytime, whereas in the winter hemisphere the maximum is during night. Those features of H m consistently indicate the prominent role of the vertical electromagnetic (E × B) drift in the equatorial ionosphere.

N-doped and double-walled carbon nanotube-modified TiO₂ (DWCNT-N/TiO₂) hybrid was synthesized using a two-step hydrothermal method and characterized using X-ray diffraction, UV-vis diffuse reflectance spectroscopy, transmission electron microscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy. DWCNT-N/TiO₂ photocatalytic activities were investigated on the basis of the photocatalytic degradation of sulfathiazole under visible light irradiation. Experimental results showed that DWCNTs in the hybrid were coated with N/TiO₂ nanoparticles, which facilitated close contact between the DWCNTs and N/TiO₂. Modification with DWCNTs contributed to the separation of photo-generated carriers and the absorption of visible light. N-doping provided the DWCNT-N/TiO₂ hybrid with enhanced absorption of visible light. The significant visible-light-driven photo-catalytic activity of the DWCNT-N/TiO₂ hybrid was caused by the synergetic effects of DWCNT modification and N-doping.

Diabetes is associated with increased mortality from Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2). Given literature suggesting a potential association between SARS-CoV-2 infection and diabetes induction, we examined pancreatic expression of the key molecule for SARS-CoV-2 infection of cells, angiotensin-converting enzyme-2 (ACE2). Specifically, we analyzed five public scRNAseq pancreas datasets and performed fluorescence in situ hybridization, Western blotting, and immunolocalization for ACE2 with extensive reagent validation on normal human pancreatic tissues across the lifespan, as well as those from coronavirus disease 2019 (COVID-19) patients. These in silico and ex vivo analyses demonstrated pancreatic expression of ACE2 is prominent in pancreatic ductal epithelium and the microvasculature, with rare endocrine cell expression of this molecule. Pancreata from COVID-19 patients demonstrated multiple thrombotic lesions with SARS-CoV-2 nucleocapsid protein expression primarily limited to ducts. SARS-CoV-2 infection of pancreatic endocrine cells, via ACE2, appears an unlikely central pathogenic feature of COVID-19 as it relates to diabetes. Funding: These efforts were supported by NIH P01 AI42288 and UC4 DK108132 (MAA), JDRF (MAA), NIH R01 DK122160 (MCT), NIH R01 AI134971 (DH), NIH P30 DK020541 (D.H.), JDRF 3-PDF-2018-575-A-N (VvdH), R01 DK093954 (CEM); VA Merit Award I01BX001733 (CEM), Imaging Core of NIH/NIDDK P30 DK097512 (CEM), gifts from the Sigma Beta Sorority, the Ball Brothers Foundation, and the George and Frances Ball Foundation (CEM), the Network for Pancreatic Organ donors with Diabetes (nPOD; RRID:SCR_014641) (5-SRA-2018-557-Q-R) and The Leona M. & Harry B. Helmsley Charitable Trust (2018PG-T1D053). Conflict of Interest: The authors declare no relevant conflicts of interest exist. Ethical Approval: Transplant-quality pancreas, duodenum, and kidney were recovered by JDRF nPOD (www.jdrfnpod.com) from 36 COVID-19 negative organ donors without diabetes (Table S2) according to established protocols and procedures (Campbell-Thompson et al., 2012), as approved by the University of Florida Institutional Review Board (201400486), the United Network for Organ Sharing (UNOS), and according to federal guidelines with informed consent obtained from each donor’s legal representative.

OBJECTIVES: Intake of n-3 polyunsaturated fatty acids (PUFAs) has been reported to provide various benefits for patients with metabolic syndrome (MetS), such as reducing blood pressure and improving blood lipids, but results are inconsistent. This study aimed to investigate the effect of n-3 PUFA intake on components of MetS. METHODS: We searched PubMed, Scopus, Web of Sciences, and Cochrane databases up to June 2018 for randomized trials at least 30 days long comparing n-3 PUFAs with a control in patients diagnosed with MetS (PROSPERO registration ID: CRD42017072332). The outcomes include body mass index, systolic and diastolic blood pressure, triglyceride, high-density lipoprotein cholesterol, and fasting blood glucose. Mean differences post-intervention or mean change from baseline were combined using random-effects models; confirmation of within-study effect sizes is ongoing. RESULTS: A total of 14 trials were identified. The pooled results showed n-3 PUFA intake reduced systolic blood pressure by 3.92 mmHg (95%CI: –6.89, –0.96, P-value = 0.009, I2 = 34%, 9 trials) and diastolic blood pressure by 2.81 mmHg (95%CI: –4.26, –1.36, P-value = 0.0001, I2 = 15%, 8 trials). Body mass index was lower in the n-3 PUFA group by 3.19 kg/m2 (95%CI: –6.16, –0.22, P-value = 0.04, I2 = 97%, 7 trials) compared to the control group. Triglyceride levels in n-3 PUFA groups were significantly lower than the control when pooling trials with post intervention data only (–33.13 mg/dL, 95%CI: –49.44, –16.81, P-value

Two novel monobenzo porphyrazines bearing nitro and methoxyl respectively on fused benzene ring were successfully synthesized. Also, an asymmetrical porphyrazine with one butylthio branch at the pyrrolic β-position substituted by hydrogen atom was successfully isolated in the course of synthesis of symmetric octakis(butylthio) porphyrazine. Their corresponding cobalt complexes were subsequently obtained and characterized. Their catalytic ability was assessed by aerobic oxidation of benzoin, showing the highest benzil yield of 95.2% for 60 min. A possible mechanism was also presented from the in-situ UV-Vis spectra, in which a novel and characteristic absorption peak of metal-oxo was observed. At the same time, similar results of the extended oxidation of benzyl alcohol also confirmed the reactive mechanism.

Fengyun-2 (FY-2) is the first generation geostationary meteorological satellites (GEOMS) in China, two of which, FY-2E and FY-2G, are operating workforce to support the dual-satellite observation mode. The onboard blackbody preliminarily used for stability monitoring of instrument's radiometric response was equipped behind its fore-optics due to the technical limitations in 1990s, which was referred as internal-blackbody (IBB) and operated on the unique preset temperature. In this article, a novel IBB calibration (IBBC) approach is proposed and the radiometric contributions of the main optical elements as well as the IBB itself are modeled and extracted. This is the most distinguishing difference from the traditional full-path blackbody calibration. The IBBC software has been in service for more than two years. Compared with high spectral resolution reference instruments recommended by Global Space-based Inter-Calibration System, the monthly mean calibration biases of long wave infrared band (IR1:10.8 µm) and water vapor band (IR3:6.95 µm) are shown to be lower than 1.5K for FY-2E and lower than 1.0K for FY-2G (for of order 90% of cases). Particularly, the annual mean biases for FY-2G IR3 band can maintain in a good state of 0.4K, which is nearly identical to that of other high class in-orbit satellites, i.e. MTSAT-2 and MSG-1. Likely impacted by ice contamination, the calibration biases of long wave split-window infrared band (IR2:12 µm) of FY-2G could be as large as -2.3K and similar phenomena once occurred in GOES-13 and MSG-1. It is expected to improve this in the near future. In general, the calibration accuracies of FY-2G IR1 and IR3 bands have reached to be lower than 1K, which is significantly superior to those of other 1st GEOMS, such as GMS-5, Meteosat-7 and GOES-4/7, whose calibration accuracies are around 2-3K. The quality of the data could be greatly enhanced so as to benefit the global observation system.

A series of thioporphyrazines have been synthesized via cocondensation from 2,3-dicyano-1,4-dithiin (A) and 2,3-bis(butylthio) maleonitrile (B) and thoroughly characterized with UV–vis, 1H NMR and MALDI-TOF MS. Through modulation of peripheral substituents of thioporphyrazines, both symmetrical and asymmetrical molecular structures in thioporphyrazines including B4, cis-A2B2, trans-A2B2 and AB3 were obtained, and were further used to react with cobalt acetate to form metal complexes, cobalt thioporphyrazines. Moreover, they were loaded on Al2O3 to form biomimetic catalysts for photocatalytic activation of dioxygen, whose efficiencies were assessed by photodegradation of Rhodamine B (RhB) in an aerated suspension under simulating sunlight irradiation. Importantly, it was found that the lower on the molecular symmetry of thioporphyrazine delivers the better on the photocatalytic activity. Electrochemical and theoretical studies demonstrated that lowering the molecular symmetry of the cobalt thioporphyrazines moderately decreased the HOMO-LUMO energy gap and increased the contribution of S atom in substitiuents to HOMO so as to enhance the photocatalytic activity. A possible mechanism to predict this reaction pattern was proposed through both detailed analysis of degradation products by HPLC and detection of the main reactive oxygen species (ROS) by ESR, indicating both energy transfer (major) and electron transfer (minor) to dioxygen to exist in the heterogeneous light photocatalytic system.

Diabetes is associated with increased mortality from severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Given literature suggesting a potential association between SARS-CoV-2 infection and diabetes induction, we examined pancreatic expression of angiotensin-converting enzyme 2 (ACE2), the key entry factor for SARS-CoV-2 infection. Specifically, we analyzed five public scRNA-seq pancreas datasets and performed fluorescence in situ hybridization, western blotting, and immunolocalization for ACE2 with extensive reagent validation on normal human pancreatic tissues across the lifespan, as well as those from coronavirus disease 2019 (COVID-19) cases. These in silico and ex vivo analyses demonstrated prominent expression of ACE2 in pancreatic ductal epithelium and microvasculature, but we found rare endocrine cell expression at the mRNA level. Pancreata from individuals with COVID-19 demonstrated multiple thrombotic lesions with SARS-CoV-2 nucleocapsid protein expression that was primarily limited to ducts. These results suggest SARS-CoV-2 infection of pancreatic endocrine cells, via ACE2, is an unlikely central pathogenic feature of COVID-19-related diabetes., Graphical Abstract, Highlights • ACE2 mRNA and protein are expressed in human pancreatic ducts and microvasculature • ACE2 mRNA was rarely detected and at low levels in human pancreatic endocrine cells • Pancreatic ACE2 protein expression changes across the lifespan and correlates with BMI • SARS-CoV-2 NP was detected in ducts, but not endocrine cells, of COVID-19 pancreata, Kusmartseva et al. demonstrate preferential ACE2 expression in pancreatic microvascular and ductal structures, suggesting these constitute a more likely target than islet endocrine cells in SARS-CoV-2 infection. This notion was supported by detection of SARS-CoV-2 nucleocapsid protein in ductal epithelium, but not endocrine cells, of pancreata from individuals with COVID-19.

In recent years, as the world has been warming, frequent natural disasters are posing a great threat to humans. By combining 5G technology with the Internet of Things (IoT) concept and increasing the placement of wireless sensor networks, disaster-prone points can be closely monitored. However, regular replacement of the traditional chemical batteries for devices that are a part of the developing IoT remains a significant challenge, especially in remote areas. In this article, we propose and report a hybrid energy harvester used in wind energy harvesting. The device consists of a rotating body and a sliding body. The electromagnetic generators (EMGs) in the rotating body and the triboelectric nanogenerators (TENGs) on the sliding body form the entirety of the power generating mechanism, and all generated units are completely sealed in the device box, which is isolated from the harsh environment. This paper not only systematically studies the influence of dielectric material types and sizes on the output performance of TENGs, but also studies the output performance of this device under different wind speeds. The results show that when the wind speed is not less than 4 m/s, the energy harvester can convert wind energy into electricity. The output performance of TENGs and EMGs increases with increasing wind speed, and the voltages of the TENG and the EMG are 416 V and 63.2 V at the 15 m/s wind speed, respectively. When the wind speed is 9 m/s, the maximum output power of TENG and EMG are 0.36 mW and 18.6 mW, respectively. The device can charge a capacitor of 1000 μF to 19.8 V in 30s. By supplying power to electronic devices and wireless monitoring systems including temperature sensors and humidity sensors, it is shown that the creation and implementation of such an energy harvester is practical and has a significant impact on promoting the development of IoT. Meanwhile, it can be used as a self-powered sensor to detected wind speed by analyzing the frequency of TENG output voltage.

Neuroinflammation after stroke significantly contributes to neuronal cell death. Bromodomain and Extra Terminal Domain (BET) proteins are essential to inflammatory gene transcription. BET proteins (BRD2, BRD3, BRD4, and BRDT) have varied effects including chromatin remodeling, histone acetyltransferase activity, and as scaffolds to recruit transcription factors; they couple chromatin remodeling with transcription. BRD2/4 are of particularly interest to stroke-induced neuroinflammation that contributes to delayed cell death as they are required for NF-κB-dependent gene transcription. We hypothesized that targeting BET proteins for degradation with dBET1, a proteolysis targeting chimera (PROTAC) that combines the highly selective BET inhibitor JQ1 and a ligand for cereblon E3 ubiquitin ligase, will reduce brain injury in ischemic stroke. Male aged mice (18–20 months old) were subjected to permanent occlusion of the middle cerebral artery and received either vehicle or dBET1 (10 mg/kg; i.p.) at various times after stroke. Neurobehavioral tests were performed before (baseline) and at 24 and 48 h after stroke induction. Infarct volume was quantified at 48 h. Data showed that BET degradation significantly reduced infarct volume in permanent focal cerebral ischemia in aged mice, and this was associated with reduced brain levels of pro-inflammatory mediators including TNF-α, CXCL1, CXCL10, CCL2, and matrix metalloproteinase-9. Treatment with dBET1 significantly reduced blood-brain barrier damage and infiltration of neutrophils into the ischemic brain. Importantly, treatment with the BET degrader dBET1 resulted in a significant improvement in stroke-induced neurological deficits. Collectively, these data indicate that BET proteins are a novel target for neuroprotection in ischemic stroke.

N-doped and double-walled carbon nanotube-modified TiO₂ (DWCNT-N/TiO₂) hybrid was synthesized using a two-step hydrothermal method and characterized using X-ray diffraction, UV-vis diffuse reflectance spectroscopy, transmission electron microscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy. DWCNT-N/TiO₂ photocatalytic activities were investigated on the basis of the photocatalytic degradation of sulfathiazole under visible light irradiation. Experimental results showed that DWCNTs in the hybrid were coated with N/TiO₂ nanoparticles, which facilitated close contact between the DWCNTs and N/TiO₂. Modification with DWCNTs contributed to the separation of photo-generated carriers and the absorption of visible light. N-doping provided the DWCNT-N/TiO₂ hybrid with enhanced absorption of visible light. The significant visible-light-driven photo-catalytic activity of the DWCNT-N/TiO₂ hybrid was caused by the synergetic effects of DWCNT modification and N-doping.

Ischemic stroke occurs when a clot forms in the brain vasculature that starves downstream tissue of oxygen and nutrients resulting in cell death. The tissue immediately downstream of the blockage, the core, dies within minutes, but the surrounding tissue, the penumbra is potentially salvageable. Prostaglandin E2 binds to four different G-protein coupled membrane receptors EP1–EP4 mediating different and sometimes opposing responses. Pharmacological activation of the EP4 receptor has already been established as neuroprotective in stroke, but the mechanism(s) of protection are not well-characterized. In this study, we hypothesized that EP4 receptor activation reduces ischemic brain injury by reducing matrix metalloproteinase (MMP)-3/-9 production and blood-brain barrier (BBB) damage. Rats underwent transient ischemic stroke for 90 min. Animals received an intravenous injection of either the vehicle or L-902,688, a highly specific EP4 agonist, at the onset of reperfusion. Brain tissue was harvested at 24 h. We established a dose-response curve and used the optimal dose that resulted in the greatest infarct reduction to analyze BBB integrity compared to vehicle-treated rats. The presence of IgG, a blood protein, in the brain parenchyma is a marker of BBB damage, and L-902,688 (1 mg/kg; i.v.) dramatically reduced IgG extravasation (P < 0.05). Consistent with these data, we assessed zona occludens-1 and occludin, tight junction proteins integral to the maintenance of the BBB, and found reduced degradation with L-902,688 administration. With immunoblotting, qRT-PCR, and/or a fluorescence resonance energy transfer (FRET)-based activity assay, we next measured MMP-3/-9 since they are key effectors of BBB breakdown in stroke. In the cerebral cortex, not only was MMP-3 activity significantly decreased (P < 0.05), but L-902,688 treatment also reduced MMP-9 mRNA, protein, and enzymatic activity (P < 0.001). In addition, post-ischemic administration of the EP4 agonist significantly reduced pro-inflammatory cytokines IL-1β (P < 0.05) and IL-6 (P < 0.01) in the ischemic cerebral cortex. Most importantly, one injection of L-902,688 (1 mg/kg; i.v) at the onset of reperfusion significantly reduces neurological deficits up to 3 weeks later (P < 0.05). Our data show for the first time that pharmacological activation of EP4 with L-902,688 is neuroprotective in ischemic stroke by reducing MMP-3/-9 and BBB damage.

Bromodomain and extraterminal (BET) proteins are essential to pro-inflammatory gene transcription. The BET family proteins, BRD2, BRD3, BRD4, and testis-specific BRDT, couple chromatin remodeling to gene transcription, acting as histone acetyltransferases, scaffolds for transcription complexes, and markers of histone acetylation. To initiate an inflammatory response, cells undergo de novo gene transcription requiring histone-modifying proteins to make DNA wrapped around histones more or less readily available to transcription complexes. Because BET proteins are the gatekeepers of nuclear factor-κB (NF-κB)-dependent gene transcription, we hypothesized that degradation of BET proteins, particularly BRD2 and BRD4, with the proteolysis-targeting chimera (PROTAC) dBET1 would dampen the pro-inflammatory response in microglia subjected to lipopolysaccharide (LPS) challenge. Degradation of BRD2 and BRD4 was associated with significantly reduced expression of several pro-inflammatory genes: inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), interleukin (IL)-1β, tumor necrosis factor-a (TNF-α), IL-6, chemokine (C-C motif) ligand 2 (CCL2), and matrix metalloproteinase-9 (MMP-9). This is the first study showing that dBET1-mediated targeted degradation of BET proteins robustly dampens pro-inflammatory responses in LPS-stimulated microglia. These data suggest that BET degradation with dBET1 will likely reduce expression of pro-inflammatory genes in in vivo neuroinflammatory models associated with microglial/immune cell activation.

TiO2 hollow microspheres (TiO2-HMSs) have attracted much attention due to their low density, high photoreactivity and easy recovery. However, fabrication of TiO2-HMSs is time-consuming and costly. In this paper, effect of H2O2 on the formation of chain-like TiO2-HMSs was studied using (NH4)2TiF6 as titanium source and urea as neutralizer through a one-pot hydrothermal reaction strategy. The prepared TiO2-HMSs were characterized by X-ray diffraction (XRD), transmission electron microscope (TEM) and scanning electron microscopy (SEM). The photocatalytic activity of TiO2-HMSs was evaluated by photocatalytic degradation of an anionic dye X3B under UV irradiation. It was found that the presence of H2O2 not only influences the nucleation, but also enhances the hollowing process of TiO2-HMSs by accelerating the “inside-outside” mass transfer. TiO2-HMSs prepared in the presence of H2O2 showed enhanced photocatalytic activity due to the synergistic effects of well crystallization and hollow structures.

A new ZnO/CoPz(hmdtn)4 composite as a highly efficient photocatalyst was successfully prepared by cobalt tetra(2-hydroxymethyl-1,4-dithiin)porphyrazine (CoPz(hmdtn)4) impregnated onto the surface of ZnO nanoparticles, the photocatalytic performance of ZnO/CoPz(hmdtn)4 under both simulated sunlight and visible light (λ ≥ 400 nm) irradiation was assessed by degradation of Rhodamine B (RhB) and phenol in aerated conditions. The ZnO/CoPz(hmdtn)4 manifested much higher photocatalytic activity than pure ZnO and pure CoPz(hmdtn)4, originating from the synergistic effect between CoPz(hmdtn)4 and ZnO. Furthermore, the XPS analysis revealed that there may be strong interaction between CoPz(hmdtn)4 and ZnO. Thereby ZnO/CoPz(hmdtn)4 with excellent stability can maintain high photocatalytic activity over five runs on the basis of the reusability test. The active species generated in the photocatalytic system were verified by electron spin resonance (ESR) technology. A possible mechanism of the synergistic effect between CoPz(hmdtn)4 and ZnO was also proposed.

Fullerene C70 modified TiO2 (C70–TiO2) hybrids were fabricated through a hydrothermal method from titanium sulfate and functionalized C70. The structures of the synthesized hybrids were characterized by X-ray diffraction, UV-vis diffuse reflectance spectroscopy, Fourier transform infrared spectroscopy, Raman spectroscopy, scanning electron microscopy, transmission electron microscopy, thermogravimetric analysis, X-ray photoelectron spectroscopy, Brunauer–Emmett–Teller surface area measurements, matrix-assisted laser desorption/ionization-time of flight-mass spectrometry and photoluminescence spectroscopy. The experimental results indicated that the introduction of C70 slightly reduces the crystallite size of TiO2 while extending its adsorption edge to the visible light region. C70 dispersed on the surface of TiO2 nanoparticles with covalent bonding, which generated strong interactions between the functionalized C70 and TiO2. The O2˙−, ˙OH and h+ are active species which were proved by the trapping experiment. The photocatalytic degradation efficiency of sulfathiazole over C70–TiO2 hybrids is higher than that over pure TiO2, C60–TiO2, and a mechanical mixture of C70 and TiO2 under visible light irradiation. The excellent visible light-induced activity is rationalized by the results of photoluminescence spectroscopy; i.e., the intensities of emissions from C70–TiO2 hybrids were found to be weaker than those from pure TiO2 and C60–TiO2 hybrid.

Selective oxidation of 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA) is one of the key reactions for producing chemical commodities from biomass and their derivatives. The challenge for this reaction is to develop an efficient catalytic process that can be conducted under mild conditions (room temperature and atmospheric pressure, using oxygen molecules in air as the oxidant) and a recyclable catalyst. Herein we report a photocatalyst of cobalt thioporphyrazine (CoPz) dispersed on g-C

Janus kinase 3 (JAK3) is associated with the common gamma chain of several interleukin (IL) receptors essential to inflammatory signaling. To study the potential role of JAK3 in stroke-induced neuroinflammation, we subjected mice to permanent middle cerebral artery occlusion and investigated the effects of JAK3 inhibition with decernotinib (VX-509) on infarct size, behavior, and levels of several inflammatory mediators. Results from our double immunofluorescence staining showed JAK3 expression on neurons, endothelial cells, and microglia/macrophages in the ischemic mouse brain (n = 3). We found for the first time that total and phosphorylated/activated JAK3 are dramatically increased after stroke in the ipsilateral hemisphere (**P

Background Resolution of inflammation is an emerging new strategy to reduce damage following ischemic stroke. Lipoxin A4 (LXA 4) is an anti-inflammatory, pro-resolution lipid mediator that reduces neuroinflammation in stroke. Since LXA 4 is rapidly inactivated, potent analogs have been synthesized, including BML-111. We hypothesized that post-ischemic, intravenous treatment with BML-111 for 1 week would provide neuroprotection and reduce neurobehavioral deficits at 4 weeks after ischemic stroke in rats. Additionally, we investigated the potential protective mechanisms of BML-111 on the post-stroke molecular and cellular profile. Methods A total of 133 male Sprague-Dawley rats were subjected to 90 min of transient middle cerebral artery occlusion (MCAO) and BML-111 administration was started at the time of reperfusion. Two methods of week-long BML-111 intravenous administration were tested: continuous infusion via ALZET ® osmotic pumps (1.25 and 3.75 μg μl-1 hr-1), or freshly prepared daily single injections (0.3, 1, and 3 mg/kg). We report for the first time on the stability of BML-111 and characterized an optimal dose and a dosing schedule for the administration of BML-111. Results One week of BML-111 intravenous injections did not reduce infarct size or improve behavioral deficits 4 weeks after ischemic stroke. However, post-ischemic treatment with BML-111 did elicit early protective effects as demonstrated by a significant reduction in infarct volume and improved sensorimotor function at 1 week after stroke. This protection was associated with reduced pro-inflammatory cytokine and chemokine levels, decreased M1 CD40+ macrophages, and increased alternatively activated, anti-inflammatory M2 microglia/macrophage cell populations in the post-ischemic brain. Conclusion These data suggest that targeting the endogenous LXA 4 pathway could be a promising therapeutic strategy for the treatment of ischemic stroke. More work is necessary to determine whether a different dosing regimen or more stable LXA 4 analogs could confer long-term protection.

Ischemic stroke occurs when a clot forms in the cerebrovasculature that starves downstream tissue of oxygen and nutrients resulting in cell death. The tissue immediately downstream of the blockage, the core, dies within minutes, but the surrounding tissue, the penumbra is potentially salvageable. Prostaglandin E 2 binds to four different G-protein coupled membrane receptors EP1-EP4 mediating different and sometimes opposing responses. Pharmacological activation of the EP4 receptor has already been established as neuroprotective in stroke, but the mechanism(s) of protection are not well characterized. In this study, we hypothesized that EP4 receptor activation reduces ischemic brain injury by reducing matrix metalloproteinase (MMP)-3/-9 production and blood-brain barrier (BBB) damage. Rats underwent transient ischemic stroke for 90 minutes. Animals received an intravenous injection of either the vehicle or L-902688, a highly specific EP4 agonist, at the onset of reperfusion. Brain tissue was harvested at 24 h. We established a dose-response curve and used the optimal dose that resulted in the greatest infarct reduction to analyze BBB integrity compared to vehicle-treated rats. The presence of IgG, a blood protein, in the brain parenchyma is a marker of BBB damage, and L-902688 (1 mg/kg; i.v.) dramatically reduced IgG extravasation. Consistent with these data, we assessed zona occludens-1, a tight junction protein integral to the maintenance of the BBB, and found it increased with L-902688 administration. With immunoblotting, qRT-PCR, and/or a fluorescence resonance energy transfer (FRET)-based activity assay developed by our group, we next measured MMP-3/-9 since they are key effectors of BBB breakdown in stroke. In the cerebral cortex, not only was MMP-3 activity significantly decreased, but L-902688 treatment also reduced MMP-9 mRNA, protein, and enzymatic activity. In addition, post-ischemic administration of the EP4 agonist significantly reduced pro-inflammatory cytokines IL-1β and IL-6 in the ischemic cortex. Our data show for the first time that pharmacological activation of EP4 with L-902688 is neuroprotective in ischemic stroke by reducing MMP-3/-9 and BBB damage.

Adropin has been shown to improve peripheral endothelial dysfunction, reduce insulin resistance, and increase glucose utilization in obesity and diabetes. Although we showed that adropin reduces paracellular permeability of brain endothelial cells exposed to ischemia-like conditions, little is known of the effects of adropin in the brain. We hypothesized that adropin exerts neuroprotection through activation of endothelial nitric oxide synthase (eNOS)/NO signaling pathway and reduction of blood-brain barrier (BBB) damage. Male mice were subjected to permanent middle cerebral artery occlusion (MCAO) and treated intravenously with either vehicle or synthetic adropin (90, 900 and 2700 nmol/kg) at the onset of ischemia and sacrificed to determine infarct size at 48 h. Cellular localization of adropin was determined using immunofluorescence. Brain tissue was collected at 24 h after stroke to determine BBB damage, matrix metalloproteinase (MMP)-9 activity, and levels of tight junction proteins, eNOS, and gp91 phox -containing NADPH oxidase. We determined the effects of a 3-h delayed administration on stroke outcomes to evaluate the translational value of adropin therapy. In the brain, adropin was expressed on endothelial cells and at a low level on astrocytes after stroke. Adropin given at the onset of MCAO dose-dependently reduced infarct size. More importantly, delaying adropin administration to 3 h post-MCAO profoundly reduced infarct size compared to vehicle-treated mice. Ischemia slightly increased eNOS phosphorylation at Ser1176, significantly increased gp91 phox (a major source of reactive oxygen species), and reduced brain adropin levels. Adropin treatment induced a dramatic increase in eNOS phosphorylation, significantly reduced gp91 phox levels, and restored endogenous adropin levels compared to the vehicle group. Additionally, adropin protected against a stroke-induced increase in MMP-9 activity, loss of zona occludens-1 and occludin, and BBB disruption as assessed by extravasated IgG and albumin. Collectively, these findings indicate that adropin-mediated neuroprotection in ischemic stroke may be through an increase in eNOS-derived NO bioavailability, reduction of gp91 phox , and decreased MMP-9 activity and BBB damage.

Hydrotalcite materials are generally utilized for anionic pollutants due to its interlayered anion exchange ability. Their potentiality for cationic contaminants is rarely explored. In this study, disulfide ( ) intercalated LDH material demonstrated capability to remove both heavy metal cations and oxyanions simultaneously from water. The intercalation of LDH significantly improved its adsorption capability towards both heavy metal cations ( and ) and oxyanion ( ). The adsorption amount of S-LDH towards and reached 88.6mg/g and 76.2mg/g, which are 405% and 281% higher than that of pristine LDH. For removal, the adsorption amount reached 34.7mg/g, 402% higher than that of pristine LDH. The cations capture mechanism mainly depends on the novel layer sheet cation substitution mechanism based on irreversible precipitation and the generation of metal sulfide precipitates. Meanwhile, the interlayered can be easily replaced by to realize the simultaneous removal of both heavy metal cations and oxyanions. In the fixed-bed column experiments, 448 bed volume (BV) (672 mL) of simulating electroplating wastewater can be efficiently treated by yielding only 1 BV(15 mL) of chemical sludge, which is practically acceptable. This work provided a highly practical adsorption technology based on the modification hydrotalcite material for the purification of heavy metal ions contaminated wastewater. Keywords: hydrotalcite heavy metal contaminants cation removal anion removal wastewater treatment

Ti3+ self-doped TiO2 nanosheets with dominant {0 0 1} facets for excellent visible-light photocatalytic activity were prepared by a facile one-pot hydrothermal reaction strategy using tetrabutyl titanate (TBT) as titanium source, hydrofluoric acid (HF) as structure-directing agent and zinc powder (Zn) as reductant. The synthesized catalysts were characterized by transmission electron microscope (TEM), X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectra (XPS), diffuse reflectance spectrum (DRS) and nitrogen adsorption–desorption isotherms. The photocatalytic activity of the photocatalyst was evaluated by measure the formation rate of photo-induced hydroxyl radicals ( OH) under visible-light irradiation (λ = 420 ± 10 nm) using coumarin as a probe. It was found that the presence of zinc shows little effect on the morphology, phase structure, BET surface areas and pore structure. However, the addition of Zn powder resulted in the formation of Ti3+ self-doped anatase TiO2 nanosheets with dominant {0 0 1} facets, which is responsible for the enhanced visible-light photocatalytic activity. The sample prepared with zinc/TBT molar ratio of 0.3 showed the highest visible-light photocatalytic activity, which is 1.9 times higher than that of commercial P25 TiO2.

Resolution of inflammation is an emerging new strategy to reduce damage following ischemic stroke. Lipoxin A4 (LXA4) is an anti-inflammatory, pro-resolution lipid mediator with high affinity binding to ALX, the lipoxin A4 receptor. Since LXA4 is rapidly inactivated, potent analogs have been created, including the ALX agonist BML-111. We hypothesized that post-ischemic intravenous administration of BML-111 would provide protection to the neurovascular unit and reduce neuroinflammation in a rat stroke model. Animals were subjected to 90 min of middle cerebral artery occlusion (MCAO) and BML-111 was injected 100 min and 24 h after stroke onset and animals euthanized at 48 h. Post-ischemic treatment with BML-111 significantly reduced infarct size, decreased vasogenic edema, protected against blood–brain barrier disruption, and reduced hemorrhagic transformation. Matrix metalloproteinase-9 and matrix metalloproteinase-3 were significantly reduced following BML-111 treatment. Administration of BML-111 dramatically decreased microglial activation, as seen with CD68, and neutrophil infiltration and recruitment, as assessed by levels of myeloperoxidase and intracellular adhesion molecule-1. The tight junction protein zona occludens-1 was protected from degradation following treatment with BML-111. These results indicate that post-ischemic activation of ALX has pro-resolution effects that limit the inflammatory damage in the cerebral cortex and helps maintain blood–brain barrier integrity after ischemic stroke. Lipoxin A4 (LXA4) is a potent anti-inflammatory, pro-resolution mediator. Post-ischemic injections of BML-111, a LXA4 receptor agonist, significantly reduced infarct size, matrix metalloproteinases, microglial activation, and neutrophil infiltration, while providing protection to the blood–brain barrier at 48 h following middle cerebral artery occlusion in rats. This suggests that activation and enhancement of the LXA4 resolution pathway may be a new target for therapeutics aimed at reducing neuroinflammation following ischemic stroke.

Background and Purpose— Targeting the prostaglandin I 2 prostanoid (IP) receptor to reduce stroke injury has been hindered by the lack of selective drugs. MRE-269 is the active metabolite of selexipag showing a high selectivity toward the IP receptor. Selexipag has been recently approved for clinical use in pulmonary hypertension. We hypothesized that postischemic treatment with MRE-269 provides long-lasting neuroprotection with improved neurological outcomes in a clinically relevant rat stroke model. Methods— Aged male Sprague–Dawley rats underwent transient middle cerebral artery occlusion and were randomly selected to receive either vehicle or MRE-269 (0.25 mg/kg) intravenously starting at 4.5 hours post ischemia. Accelerating rotarod and adhesive removal tests were conducted before and at 3, 7, 14, and 21 days after stroke. Infarct volume was quantified by magnetic resonance imaging at 48 hours and 21 days post middle cerebral artery occlusion. In parallel experiments, cerebral cortex samples from stroke and nonstroke sides from vehicle- and MRE-269–treated groups were collected at 18 hours post middle cerebral artery occlusion for molecular biology analyses. Results— Quantitative magnetic resonance imaging data showed that postischemic MRE-269 treatment significantly reduced infarct volume compared with vehicle-treated rats at both 48 hours and 3 weeks after stroke. MRE-269 treatment resulted in a significant long-term recovery in both locomotor and somatosensory functions after middle cerebral artery occlusion, which was associated with a reduced weight loss in animals receiving the IP receptor agonist. Postischemic MRE-269 treatment reduced proinflammatory cytokines/chemokines and oxidative stress. Damage to the blood–brain barrier, as assessed by extravasation of immunoglobulin G to the ischemic brain, was significantly reduced by MRE-269, which was associated with a reduction in matrix metalloproteinase-9 activity in the brain of stroked aged rats given the IP agonist at 4.5 hours after ischemia onset. Conclusions— Our data suggest that targeting the IP receptor with MRE-269 is a novel strategy to reduce cerebral ischemia injury and promote long-term neurological recovery in ischemic stroke.

Brain edema occurs in response to stroke, intracerebral hemorrhage, traumatic brain injury, meningitis, brain tumors, and neuroinflammation. Disruption of the blood–brain barrier (BBB) is associated with vasogenic edema. Increased proteolytic activity of matrix metalloproteinases (MMPs) leads to increased BBB permeability by degrading tight junction proteins and basement membrane components, as well as interfering with cell–cell interactions in the neurovascular unit. In this chapter, we discuss the potential role of the MMPs in BBB dysfunction, edema formation, hemorrhagic transformation, and neuronal cell death following brain injury. Understanding how the MMPs contribute to the pathogenesis of cerebral edema could help to identify novel targets to reduce its devastating consequences in many neurological diseases.

A novel magnetically recoverable thioporphyrazine catalyst (CoPz(S-Bu)8/SiO2@Fe3O4) was prepared by immobilization of the cobalt octkis(butylthio) porphyrazine complex (CoPz(S-Bu)8) on silica-coated magnetic nanospheres (SiO2@Fe3O4). The composite CoPz(S-Bu)8/SiO2@Fe3O4 appeared to be an active catalyst in the oxidation of benzyl alcohol in aqueous solution using hydrogen peroxide (H2O2) as oxidant under Xe-lamp irradiation, with 36.4% conversion of benzyl alcohol, about 99% selectivity for benzoic acid and turnover number (TON) of 61.7 at ambient temperature. The biomimetic catalyst CoPz(S-Bu)8 was supported on the magnetic carrier SiO2@Fe3O4 so as to suspend it in aqueous solution to react with substrates, utilizing its lipophilicity. Meanwhile the CoPz(S-Bu)8 can use its unique advantages to control the selectivity of photocatalytic oxidation without the substrate being subjected to deep oxidation. The influence of various reaction parameters on the conversion rate of benzyl alcohol and selectivity of benzoic acid was investigated in detail. Moreover, photocatalytic oxidation of substituted benzyl alcohols was obtained with high conversion and excellent selectivity, specifically conversion close to 70%, selectivity close to 100% and TON of 113.6 for para-position electron-donating groups. The selectivity and eco-friendliness of the biomimetic photocatalyst give it great potential for practical applications.

Background Resolution of inflammation is an emerging new strategy to reduce damage following ischemic stroke. Lipoxin A4 (LXA 4) is an anti‐inflammatory, pro‐resolution lipid mediator that reduces neuroinflammation in stroke. Since LXA 4 is rapidly inactivated, potent analogs have been synthesized, including BML‐111. We hypothesized that post‐ischemic, intravenous treatment with BML‐111 for 1 week would provide neuroprotection and reduce neurobehavioral deficits at 4 weeks after ischemic stroke in rats. Additionally, we investigated the potential protective mechanisms of BML‐111 on the post‐stroke molecular and cellular profile. Methods A total of 133 male Sprague‐Dawley rats were subjected to 90 min of transient middle cerebral artery occlusion (MCAO) and BML‐111 administration was started at the time of reperfusion. Two methods of week‐long BML‐111 intravenous administration were tested: continuous infusion via ALZET ® osmotic pumps (1.25 and 3.75 μg μl−1 hr−1), or freshly prepared daily single injections (0.3, 1, and 3 mg/kg). We report for the first time on the stability of BML‐111 and characterized an optimal dose and a dosing schedule for the administration of BML‐111. Results One week of BML‐111 intravenous injections did not reduce infarct size or improve behavioral deficits 4 weeks after ischemic stroke. However, post‐ischemic treatment with BML‐111 did elicit early protective effects as demonstrated by a significant reduction in infarct volume and improved sensorimotor function at 1 week after stroke. This protection was associated with reduced pro‐inflammatory cytokine and chemokine levels, decreased M1 CD40+ macrophages, and increased alternatively activated, anti‐inflammatory M2 microglia/macrophage cell populations in the post‐ischemic brain. Conclusion These data suggest that targeting the endogenous LXA 4 pathway could be a promising therapeutic strategy for the treatment of ischemic stroke. More work is necessary to determine whether a different dosing regimen or more stable LXA 4 analogs could confer long‐term protection.

In vivo or ex vivo electron paramagnetic resonance imaging (EPRI) is a powerful technique for determining the spatial distribution of free radicals and other paramagnetic species in living organs and tissues. However, applications of EPRI have been limited by long projection acquisition times and the consequent fact that rapid gated EPRI was not possible. Hence in vivo EPRI typically provided only time-averaged information. In order to achieve direct gated EPRI, a fast EPR acquisition scheme was developed to decrease EPR projection acquisition time down to 10–20 ms, along with corresponding software and instrumentation to achieve fast gated EPRI of the isolated beating heart with submillimeter spatial resolution in as little as 2–3 min. Reconstructed images display temporal and spatial variations of the free-radical distribution, anatomical structure, and contractile function within the rat heart during the cardiac cycle. Magn Reson Med, 2013. © 2012 Wiley Periodicals, Inc.

Fluoropolymer poly-vinylidene-fluoride modified TiO 2 (PVDF/TiO 2 ) were prepared via a simple chemisorption approach and characterized by thermo gravimetric analyse, transmission electron microscope, X-ray diffraction, X-ray photoelectron spectroscopy and photoluminescence spectra. The modified mechanism and the photocatalytic selectivity of the PVDF/TiO 2 were studied. The existence of Ti-F coordination bond on the interface between TiO 2 and PVDF was confirmed. For the PVDF modification, the photocatalytic degradation (PCD) of cationic dye was greatly enhanced, and the PCD of anionic dye was obviously inhibited. PVDF/TiO 2 shows high photocatalytic selectivity than that of TiO 2 by degrading mixed solution of cationic dyes MB and anionic dyes MO. The selectivity can be tuned by changing the PVDF modification amount.