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Redox mediators (RMs) are widely utilized in the electrolytes of Li-O 2 batteries to catalyze the formation/decomposition of Li 2 O 2 , which significantly enhances the cycling performance and reduces the charge overpotential. However, RMs have a shuttle effect by migrating to the Li anode side and inducing Li metal degradation through a parasitic reaction. Herein, a metal-organic framework gel (MOF-gel) separator is proposed to restrain the shuttling of RMs. Compared to traditional MOF nanoparticles, MOF gels form uniform and dense films on the separators. When using Ru(acac) 3 (ruthenium acetylacetonate) as an RM, the MOF-gel separator suppresses the shuttling of Ru(acac) 3 toward the Li anode side and significantly enhances the performance of Li-O 2 batteries. Specifically, Li-O 2 batteries exhibit an ultralong cycling life (410 cycles) at a current density of 0.5 A g -1 . Moreover, the batteries using the MOF-gel/celgard separator exhibit significantly improved cycling performance (increase by ≈1.6 times) at a high current density of 1.0 A g -1 and a decreased charge/discharge overpotential. This result is expected to guide future development of battery separators and the exploration of redox mediators., (© 2024 Wiley‐VCH GmbH.)

Hierarchical carbon nanocages as emerging nanomaterials have a great potential for photothermal therapy due to their unique porous structure, high specific surface area, and excellent photothermal property. Herein, a hierarchical nitrogen-doped carbon nanocage (hNCNC) is introduced as a second near-infrared photothermal agent, and then functionalizes it with metal-organic hydrogel (MOG) to form a thermal-responsive switch for sensitized photothermal therapy. Upon 1064 nm light irradiation, the hNCNCs exhibit a remarkable photothermal conversion efficiency of 65.9% owing to a high near-infrared extinction coefficient. Meanwhile, due to the hierarchical structure, hNCNCs show 60.2% (wt./wt.) loading efficiency of quercetin, a heat shock protein (Hsp70) inhibitor. Through thermal-driven dry-gel transformation, the coating MOGs intelligently release the encapsulated quercetin for sensitizing cancer cells to heat. Based on the synergistic effect of hyperthermia elevation and thermal-driven drug release, the dual thermal utilization platform achieves effective photothermal tumor ablation in vivo under low concentration of hNCNCs and mild irradiation, which provides a new diagram of intelligent responsive photothermal agents for enhanced photothermal therapy., (© 2023 Wiley-VCH GmbH.)

Background: Diabetic nephropathy is a complex disease with poor outcomes, and our current treatment measures are limited. It is urgent to search for novel therapeutic targets. Recently, a mesangium-predominant gene, megsin, has emerged as a participant in mesangial cell proliferation and/or mesangial matrix expansion. This study investigated the effect of megsin down-regulation on the progression of diabetic nephropathy., Methods: Streptozotocin (STZ)-induced diabetic CD-1 mice after uninephrectomy received a pBAsi mU6 Neo megsin siRNA plasmid for 12 weeks and were compared with age-matched nondiabetic mice. In vitro mouse mesangial cells were transfected with pBAsi mU6 Neo megsin siRNA plasmid using Lipofectamine 2000 reagent and further cultured in DMEM containing high glucose for up to 48 hours. All of the cells were collected for protein extraction and the supernatant for type IV collagen measurement. The expression of megsin, matrix metalloproteinase-2 (MMP-2), tissue inhibitor of metalloproteases-2 (TIMP-2) and p27(Kip1) was determined by Western blotting., Results: The megsin siRNA plasmid alleviated proteinuria and glomerular type IV collagen accumulation 12 weeks after the STZ injection, down-regulated renal cell proliferation and normalized the imbalance between MMP-2 and TIMP-2. Also, in vitro experiments showed that the glomerular mesangial cellular proliferation and type IV collagen production induced by high glucose were relieved after the transfection of megsin siRNA plasmid. The level of p27(kip1) was down-regulated in transfected mesangial cells significantly., Conclusions: The study suggests that the down-regulation of megsin might exert beneficial effects on the diabetic kidney partly through down-regulation of p27(kip1) level and that megsin may serve as a novel therapeutic target in the management of diabetic nephropathy.

Simultaneous full scan-selected ion monitoring mode (Scan-SIM) is a new improvement method of data acquisition of gas chromatography-mass spectrometry (GC-MS). A method of determing alkaloids in tobacco was established by GC-MS with Scan-SIM. Nicotine, nornicotine, anabasine and anatabine were determined with scan mode, and myosmine, nicotyrine, 2,3'-bipyridyl and cotinine were determined with SIM mode. The average recoveries of alkaloids ranged from 94.8% to 98.8%, and the relative standard deviations were less than 6.0% (n = 5). Therefore, it is a simple, rapid, accurate method. Tobacco samples picked in different years were determined using this method, and the results were satisfactory.

A fast method for determination of polycyclic aromatic hydrocarbons (PAHs) in water samples was established. The samples from the Dianchi Lake and Panlong River were analyzed directly using stir bar sorptive extraction-thermal desorption system-gas chromatography/ mass spectrometry (SBSE-TDS-GC/MS). Polydimethylsiloxane (PDMS) was used as the extraction phase. The samples were extracted with stir bars at 1100 r/min for 60 min at ambient temperature (25 degrees C). Desorption was carried out at 300 degrees C for 5 min under a helium flow of 50 mL/min in the splitless mode while maintaining a cryofocusing temperature of 0 degrees C in the programmed-temperature vaporization (PTV) injector of the GC/MS system. The limits of detection of PAHs ranged from 1.0 pg to 468.8 pg. The theoretical recoveries of PAHs were greater than 90% (except that naphthalene was 64.90%), and the recoveries of 16 PAHs from water samples ranged from 83.1% to 109.4%, and the relative standard deviations (RSDs) ranged from 1.2% to 9.3% (n = 6). PAHs in Dianchi Lake and Panlong River samples were quantified rapidly by this method. The results show that, the total content of these 16 PAHs is 89.16 ng/L in Dianchi Lake, 65.41 ng/L in the up-stream of Panlong River, 339.22 ng/L in the middle-stream of Panlong River and 62.25 ng/L in the down-stream of Panlong River. It is demonstrated that the Dianchi Lake and Panlong River were polluted by PAHs to some degree.

Relationships between tobacco compounds and smoke products are complex and often difficult to unravel. Pyrolysis experiments have frequently been used to establish such relationships. The relevance of pyrolysis experiments to the behavior of tobacco constituent in a burning cigarette was studied. A set of pyrolysis conditions has been developed to study the effect of thermal degradation of beta-carotene to the cigarette smoke quality, and the conditions was approximated to those occurring in the pyrolysis region of the burning cigarette. The pyrolysates of beta-carotene were investigated in air, 10% O2 (in N2) and N2 at three temperature levels of 300 degrees C, 600 degrees C and 900 degrees C, respectively. The pyrolysates were adsorbed by solid-phase microextraction (SPME) and then analyzed by gas chromatography/mass spectrometry (GC/ MS). Under the different conditions, the major pyrolysates from beta-carotene are hydrocarbon compounds such as toluene, p-xylene, 1, 2, 3, 4-tetrahydro-1, 1, 6-trimethyl-naphthalene and 2, 7-dimethyl-naphthalene, and some important flavors existing in cigarette smoke such as isophorone, 2, 6, 6-trimethyl-1-cyclohexene-1-carboxaldehyde, beta-ionone and 5, 6, 7, 7a-tetrahydro-4, 4, 7 a-trimethyl-2 (4H)-benzofuranone. The amount of these pyrolysates alters with the change of pyrolysis temperature levels and the concentration of oxygen.

To further understand the effect of tobacco stems in tobacco blend, a detailed comparative study of chemical components of tobacco leaves and stems before and after combustion was carried out. Pyrolysis of tobacco leaves and stems was carried out by a CDS Pyrolyser 2000 coupled to a Finnigan 8000(TOP) Gas Chromatograph and a Voyager Mass Spectrometer (GC-MS). A modified apparatus of pyrolysis was used to emulate the behavior of combustion of cigarette. A set of pyrolysis conditions was also developed that approximated those occurring in the pyrolysis region of the burning cigarette. The conditions included heating the sample at 20 degrees C/ms from 30 degrees C to 300 degrees C, 600 degrees C and 900 degrees C in air, and their pyrolysates were analyzed by GC-MS. The results indicated that the values of routine chemical constituents in tobacco leaves and stems were obviously different. The pyrolysates belonged to numerous classes of compounds such as hydrocarbons, alcohols, phenols, aldehydes, ketones, nitriles, alkaloids etc. The kinds of pyrolysates of tobacco leaves and stems were positively related to the pyrolysis temperature levels. On the other hand, at the same temperature level, the types of the pyrolysates from the tobacco leaves were much more than those from the tobacco stems.