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Mildly-acidic MnO2-Zn batteries are considered as a promising alternative for large-scale energy storage systems for their low toxicity, high safety, and low cost. Though, the degradation of MnO2 with cycling still hinders the further development of the batteries. In this study, it is observed that the decrease in available capacity of MnO2 with charge and discharge is accompanied by a structural transformation with the emergence of ZnâMnâO phases. An electrodeposition test indicates that the ZnâMnâO phase is formed from a co-precipitation of Zn and Mn during the charge process. Further, the structural change of MnO2 is suppressed and its cycle stability is improved with the addition of TiOSO4 as a facile electrolyte additive. As a result, under a current of 1200 mA g-1, the MnO2 electrode still gives a capacity of 230 mAh g-1 for over 1500 cycles. Capacity retention is 75% after 10 000 cycles under a current rate of 4800 mA g-1. These findings provide fundamental insights on the degradation mechanism of MnO2 and a new strategy to improve the electrochemical performance of aqueous MnO2-Zn batteries.
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Molecule sieve effect (MSE) can enable direct separation of target, thus overcoming two major scientific and industrial separation problems in traditional separation, coadsorption, and desorption. Inspired by this, herein, the concept of coordination sieve effect (CSE) for direct separation of UO2 2+ , different from the previously established two-step separation method, adsorption plus desorption is reported. The used adsorbent, polyhedron-based hydrogen-bond framework (P-HOF-1), made from a metal-organic framework (MOF) precursor through a two-step postmodification approach, afforded high uptake capacity (close to theoretical value) towards monovalent Cs+ , divalent Sr2+ , trivalent Eu3+ , and tetravalent Th4+ ions, but completely excluded UO2 2+ ion, suggesting excellent CSE. Direct separation of UO2 2+ can be achieved from a mixed solution containing Cs+ , Sr2+ , Eu3+ , Th4+ , and UO2 2+ ions, giving >99.9% removal efficiency for Cs+ , Sr2+ , Eu3+ , and Th4+ ions, but <1.2% removal efficiency for UO2 2+ , affording benchmark reverse selectivity (SM/U ) of >83 and direct generation of high purity UO2 2+ (>99.9%). The mechanism for such direct separation via CSE, as unveiled by both single crystal X-ray diffraction and density-functional theory (DFT) calculation, is due to the spherical coordination trap in P-HOF-1 that can exactly accommodate the spherical coordination ions of Cs+ , Sr2+ , Eu3+ , and Th4+ , but excludes the planar coordination UO2 2+ ion.
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Precise ion recognition plays a key role in the anionic decontamination in water. However, the established anionic recognition based on neutral or cationic anion receptor is still restricted by the inherent limitation, such as narrow application scope in organic solvent rather than water for neutral anion receptor and poor selectivity due to non-directional electrostatic interaction for cationic anion receptor. Herein, for the first time, a neutral metal-organic framework (MOF) anion receptor is shown, enabling precise anion recognition, for example, the presence of a variety of 1000-fold competitive anions does not affect the selective adsorption of the target anion at all. A radical-dominating anion-recognition mechanism is proposed for rationalizing the efficacy of the neutral MOF.
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Degradation of naproxen (NAP) by persulfate (PS) activated with zero-valent iron (ZVI) was investigated in our study. The NAP in aqueous solution was degraded effectively by the ZVI/PS system and the degradation exhibited a pseudo-first-order kinetics pattern. Both sulfate radical (SO4 â¢-) and hydroxyl radical (HOâ¢) participate in the NAP degradation. The second-order rate constants for NAP reacting with SO4 â¢- and HO⢠were (5.64 ± 0.73) × 109 M- 1 s- 1 and (9.05 ± 0.51) × 109 M- 1 s- 1, respectively. Influence of key parameters (initial pH, PS dosage, ZVI dosage, and NAP dosage) on NAP degradation were evaluated systematically. Based on the detected intermediates, the pathways of NAP degradation in ZVI/PS system was proposed. It was found that the presence of ammonia accelerated the corrosion of ZVI and thus promoted the release of Fe2+, which induced the increased generation of sulfate radicals from PS and promoted the degradation of NAP. Compared to its counterpart without ammonia, the degradation rates of NAP by ZVI/PS were increased to 3.6-17.5 folds and 1.2-2.2 folds under pH 7 and pH 9, respectively.
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Hierro , Contaminantes Químicos del Agua , Cinética , Naproxeno , Oxidación-ReducciónRESUMEN
Heavy metal contamination of water resources is a critical issue which adversely affects humans. Ferrate(VI) (FeVIO4 2-, Fe(VI)), as a new type of green multifunctional water treatment agent, has shown promising potential for environmental decontamination. A complete understanding of the interactions between ferrate(VI) and toxic metals can be conducive to the further development of ferrate(VI) technology for application to wastewater treatment. This review first introduces the purification of ferrate(VI) technology for toxic metals including free heavy metals and metal complexes briefly. The effective parameters are then analyzed and discussed in detail. Subsequently, the reactivity and mechanisms of ferrate(VI) with toxic metals are emphatically described. Finally, possible research challenges and directions for ferrate(VI) technology applied to wastewater treatment in the future are summarized.
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Contaminantes Químicos del Agua , Purificación del Agua , Humanos , Hierro , Oxidación-Reducción , Aguas ResidualesRESUMEN
Caulophyllum robustum Maxim (CRM) is a Chinese folk medicine with significant effect on treatment of rheumatoid arthritis (RA). This study was designed to explore the spectrum-effect relationships between high-performance liquid chromatography (HPLC) fingerprints and the anti-inflammatory effects of CRM. Seventeen common peaks were detected by fingerprint similarity evaluation software. Among them, 15 peaks were identified by Liquid Chromatography-Mass Spectrometry (LC-MS). Pharmacodynamics experiments were conducted in collagen-induced arthritis (CIA) mice to obtain the anti-inflammatory effects of different batches of CRM with four pro-inflammation cytokines (TNF-α, IL-ß, IL-6, and IL-17) as indicators. These cytokines were suppressed at different levels according to the different batches of CRM treatment. The spectrum-effect relationships between chemical fingerprints and the pro-inflammation effects of CRM were established by multiple linear regression (MLR) and gray relational analysis (GRA). The spectrum-effect relationships revealed that the alkaloids (N-methylcytisine, magnoflorine), saponins (leiyemudanoside C, leiyemudanoside D, leiyemudanoside G, leiyemudanoside B, cauloside H, leonticin D, cauloside G, cauloside D, cauloside B, cauloside C, and cauloside A), sapogenins (oleanolic acid), ß-sitosterols, and unknown compounds (X3, X17) together showed anti-inflammatory efficacy. The results also showed that the correlation between saponins and inflammatory factors was significantly closer than that of alkaloids, and saponins linked with less sugar may have higher inhibition effect on pro-inflammatory cytokines in CIA mice. This work provided a general model of the combination of HPLC and anti-inflammatory effects to study the spectrum-effect relationships of CRM, which can be used to discover the active substance and to control the quality of this treatment.
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Antiinflamatorios/química , Antiinflamatorios/farmacología , Caulophyllum/química , Citocinas/metabolismo , Mediadores de Inflamación/metabolismo , Extractos Vegetales/química , Extractos Vegetales/farmacología , Animales , Artritis Experimental/tratamiento farmacológico , Artritis Experimental/metabolismo , Artritis Experimental/patología , Biomarcadores , Caulophyllum/clasificación , Cromatografía Líquida de Alta Presión , Análisis por Conglomerados , Citocinas/sangre , Ensayo de Inmunoadsorción Enzimática , Mediadores de Inflamación/sangre , RatonesRESUMEN
In this paper, an extraction technology has been investigated to recover gallic acid (GA) from GA processing wastewater. The effects of phase ratio and pH on the extraction behaviour of tributyl phosphate (TBP)/kerosene were investigated using TBP as the extractant and kerosene as the diluent. Our results showed that using 30% TBP, equilibrium was reached in 1â min. Extraction yields could be improved by increasing the phase ratio (organic phase:aqueous phase). The optimum pH values for the extraction and stripping processes were 3 and 6-9, respectively. The different GA concentrations had no noticeable effects on the distribution ratio between the organic phase and the aqueous phase during the extraction and stripping processes. The extraction yield that resulted from using the six-stage concentrating extraction was greater than 93%, with a phase ratio of 1:1 and an initial pH of 0.6. The GA concentration in the four-stage stripping liquor was greater than 100â gâ L(-1). Overall, the results indicated that the recovery of GA from GA processing wastewater is feasible using the methods described in this paper.
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Conservación de los Recursos Naturales , Ácido Gálico/aislamiento & purificación , Queroseno , Organofosfatos/química , Termodinámica , Aguas ResidualesRESUMEN
Anion-intercalation lithium metal batteries (AILMBs) are appealing due to their low cost and fast intercalation/de-intercalation kinetics of graphite cathodes. However, the safety and cycliability of existing AILMBs are constrained by the scarcity of compatible electrolytes. Herein, we showcase that a difluoroester can be applied as electrolyte solvent to realize high-performance AILMBs, which not only endows high oxidation resistance, but also efficiently tunes the solvation shell to enable highly reversible and kinetically fast cathode reaction beyond the trifluoro counterpart. The difluoroester-based electrolyte demonstrates nonflammability, high ionic conductivity, and electrochemical stability, along with excellent electrode compatibility. The Li| |graphite AILMBs reach a high durability of 10000 cycles with only a 0.00128% capacity loss per cycle under fast-cycling of 1 A g-1, and retain ~63% of room-temperature capacity when discharging at -65 °C, meanwhile supply stable power output under deformation and overcharge conditions. The electrolyte design paves a promising path toward fast-rate, low-temperature, durable, and safe AILMBs.
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miR-17-5p has been found to be involved in the proliferation and metastasis of colorectal cancer (CRC), and N6-methyladenosine (m6A) modification is the most common RNA modification in eukaryotes. However, whether miR-17-5p contributes to chemotherapy sensitivity in CRC via m6A modification is unclear. In this study, we found that overexpression of miR-17-5p led to less apoptosis and lower drug sensitivity in vitro and in vivo under the 5-fluorouracil (5-FU) treatment, which indicated miR-17-5p led to 5-FU chemotherapy resistance. Bioinformatic analysis suggested that miR-17-5p-mediated chemoresistance was associated with mitochondrial homeostasis. miR-17-5p directly bound to the 3' untranslated region of Mitofusin 2 (MFN2), leading to decreased mitochondrial fusion and enhanced mitochondrial fission and mitophagy. Meanwhile, methyltransferase-like protein 14 (METTL14) was downregulated in CRC, resulting in lower m6A level. Moreover, the low level of METTL14 promoted the expression of pri-miR-17 and miR-17-5p. Further experiments suggested that m6A mRNA methylation initiated by METTL14 inhibits pri-miR-17 mRNA decay via reducing the recognition of YTHDC2 to the "GGACC" binding site. The METTL14/miR-17-5p/MFN2 signaling axis may play a critical role in 5-FU chemoresistance in CRC.
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Neoplasias Colorrectales , MicroARNs , Humanos , Línea Celular Tumoral , Resistencia a Antineoplásicos/genética , Neoplasias Colorrectales/patología , MicroARNs/genética , Fluorouracilo/farmacología , Metiltransferasas/metabolismo , Homeostasis , Regulación Neoplásica de la Expresión Génica , Proliferación Celular/genéticaRESUMEN
Alzheimer's disease (AD) has become the most common age-related dementia in the world and is currently incurable. Although many efforts have been made, the underlying mechanisms of AD remain unclear. Extracellular amyloid-beta deposition, intracellular tau hyperphosphorylation, neuronal death, glial cell activation, white matter damage, blood-brain barrier disruption, and other mechanisms all take part in this complicated disease, making it difficult to find an effective therapy. In the study of therapeutic methods, how to restore functional neurons and integrate myelin becomes the main point. In recent years, with the improvement and maturity of induced pluripotent stem cell technology and direct cell reprogramming technology, it has become possible to induce non-neuronal cells, such as fibroblasts or glial cells, directly into neuronal cells in vitro and in vivo. Remarkably, the induced neurons are functional and capable of entering the local neural net. These encouraging results provide a potential new approach for AD therapy. In this review, we summarized the characteristics of AD, the reprogramming technique, and the current research on the application of cellular reprogramming in AD. The existing problems regarding cellular reprogramming and its therapeutic potential for AD were also reviewed.
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A novel 3.3 V copper-lithium battery using a copper foil as the cathode is a potential candidate for next-generation energy storage system due to its simple manufacturing process. However, the cross-over of copper ions from the cathode to the anode limits the reversibility of the battery. Herein, we suppress self-discharge and migration of copper ions in the cell using a commercial polypropylene separator with a coating of polyacrylic acid (PAA), a chelating polymer. Fourier transform infrared spectroscopy confirms that the PAA layer traps the copper ions and prevents them from passing through. The addition of barium titanate nanoparticles into the PAA layer further enhances ionic transfer through the separator and reduces polarization of the cell at high current rates during charge and discharge. The use of a chelating agent with an inorganic filler as a coating layer on the separator is a cost-effective way to improve reversibility and round-trip efficiency of copper-lithium batteries.
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Toll-like receptor-2 (TLR2), a member of the TLR family, plays an important role in the initiation and regulation of immune/inflammation response, which is a critical mechanism underlying Alzheimer's disease (AD). To clarify the role of TLR2 in the pathological process of AD, in the present study, TLR2 knockout plus APPswe/PSEN1dE9 transgenic mice (AD-TLR2KO) were generated. Neurobehavioral tests and brain MRI scan were conducted on mice at the age of 12 months. Additionally, neuron loss was evaluated using NeuN staining. Amyloid ß protein (Aß), glial fibrillary acidic protein (GFAP), endogenous ligands for TLR2, and the activation of downstream signaling of TLR2 in mouse brains were detected by immunohistochemistry and Western blots. The results demonstrated that TLR2 deficit induced learning disabilities, decreased spontaneous activity, increased anxiety and depression, and led to white matter damage (WMD), brain atrophy, loss of neurons, and glial activation. Moreover, TLR2 deficit aggravated impaired neurobehavioral functions and WMD in AD mice, but did not affect the Aß deposition in mouse brains. Our data indicate that the genomic deletion of TLR2 impairs neurobehavioral functions, induces WMD and brain atrophy, and increases the activation of astrocytes, which in turn aggravate the symptoms of AD through a non-Aß mechanism.
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Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/psicología , Receptor Toll-Like 2/genética , Sustancia Blanca/patología , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/metabolismo , Animales , Ansiedad/genética , Disfunción Cognitiva/genética , Depresión/genética , Imagen de Difusión Tensora , Modelos Animales de Enfermedad , Femenino , Proteína Ácida Fibrilar de la Glía/metabolismo , Masculino , Aprendizaje por Laberinto , Ratones Noqueados , Actividad Motora/genética , Plasticidad Neuronal , Sustancia Blanca/diagnóstico por imagenRESUMEN
This study investigated the effects of progesterone (PROG) on neonatal hypoxic/ischemic (NHI) brain injury, the differences in effects between genders, and the underlying mechanisms. NHI brain injury was established in both male and female neonatal mice induced by occlusion of the left common carotid artery followed by hypoxia. The mice were treated with PROG or vehicle. Fluoro-Jade B staining (F-JB), long term behavior testing, and brain magnetic resonance image (MRI) were applied to evaluate neuronal death, neurological function, and brain damage. The underlying molecular mechanisms were also investigated by Western blots. The results showed that, in the male mice, administration of PROG significantly reduced neuronal death, improved the learning and memory function impaired by cerebral HI, decreased infarct size, and maintained the thickness of the cortex after cerebral HI. PROG treatment, however, did not show significant neuroprotective effects on female mice subjected to HI. In addition, the data demonstrated a gender difference in the expression of tumor necrosis factor receptor 1 (TNFR1), TNF receptor associated factor 6 (TRAF6), Fas associated protein with death domain (FADD), and TIR-domain-containing adapter-inducing interferon-ß (TRIF) between males and females. Our results indicated that treatment with PROG had beneficial effects on NHI injured brain in acute stage and improved the long term cognitive function impaired by cerebral HI in male mice. In addition, the activation of TNF and TRIF mediated signaling in response to cerebral HI and the treatment of PROG varied between genders, which highly suggested that gender differences should be emphasized in evaluating neonatal HI brain injury and PROG effects, as well as the underlying mechanisms.
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Hipoxia-Isquemia Encefálica/tratamiento farmacológico , Fármacos Neuroprotectores/uso terapéutico , Progesterona/uso terapéutico , Animales , Animales Recién Nacidos , Encéfalo/patología , Estenosis Carotídea , Cognición/efectos de los fármacos , Femenino , Hipoxia-Isquemia Encefálica/patología , Imagen por Resonancia Magnética , Masculino , Aprendizaje por Laberinto/efectos de los fármacos , Ratones , Ratones Endogámicos C57BL , Receptores Tipo I de Factores de Necrosis Tumoral/biosíntesis , Receptores Tipo I de Factores de Necrosis Tumoral/genética , Caracteres Sexuales , Factor 6 Asociado a Receptor de TNF/biosíntesis , Factor 6 Asociado a Receptor de TNF/genéticaRESUMEN
Caulophyllum robustum Maxim (C. robustum) has commonly been used as traditional Chinese medicine for the treatment of rheumatic pain and rheumatoid arthritis (RA) in China. This paper first investigated the anti-inflammation effect of C. robustum extraction (CRME) on RAW264.7 cells stimulated by lipopolysaccharide (LPS) and gene expression levels of inflammatory factors. Moreover, we first evaluated the anti-RA effects of CRME using collagen-induced arthritis (CIA) in DBA/1J mice, and the incidence, clinical score, and joint histopathology were evaluated. The levels of IL-1, IL-6, TNF-α, and PGE2 inflammatory factors in sera of mice were detected by enzyme-linked immunosorbent assay. The expression of NF-κB p65 in the joint was tested by immune histochemical technique. The results showed that, compared with the model group, CRME significantly improved symptoms of the arthritis index, limb swelling, and histological findings by decreasing synovial membrane damage, the extent of inflammatory cell infiltration, and the expansion of capillaries in CIA mice. The results also showed that CRME can reduce the levels of IL-1, IL-6, TNF-α, and PGE2 and inhibit the expression of NF-κB p65. All these results indicated the anti-inflammatory efficacy of CRME as a novel botanical extraction for the treatment of RA.