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1.
Ecotoxicol Environ Saf ; 225: 112745, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34481349

RESUMO

In the present work, hematite-boron-carbonitride (Fe2O3-BCN) nanosheets were synthesized by a simple hydrothermal reaction and the following high temperature treatment. The morphology, structure and chemical composition of the as-prepared material were carefully characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The Fe2O3-BCN nanosheets were used to modified on the surface of the glassy carbon electrode to fabricate an electrochemical sensor for lead ions (Pb(II)) via differential pulse anodic stripping voltammetry (DPASV). At the same time, the influence of the modification concentration, solution acidity, deposition potential and deposition time on response peak current of Pb(II) at the Fe2O3-BCN-based electrochemical sensor was well investigated. Under the optimized conditions, the electrochemical signal and concentration of Pb(II) show two-stage linear relationship in the range of 0.5 - 40 µg/L and 40 -140 µg/L, with a limit of detection (LOD) of 0.129 µg/L. The Fe2O3-BCN-based electrochemical sensor shows excellent selectivity and anti-interference ability in the anti-interference experiments and actual sample analysis experiments, revealing its broad application in environmental monitoring of Pb(II).

2.
J Am Heart Assoc ; 10(18): e021369, 2021 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-34482701

RESUMO

Background Pathophysiologic mechanisms underlying cardiac structural and functional changes in obesity are complex and linked to adipocytokines released from pericardial adipose tissue (PAT) and cardiomyocyte apoptosis. Although leptin is involved in various pathological conditions, its role in paracrine action of pericardial adipose tissue on myocardial apoptosis remains unknown. This study was designed to investigate the role of PAT-derived leptin on myocardial apoptosis in high-fat diet-induced obese rats. Methods and Results Hearts were isolated from lean or high-fat diet-induced obese Wistar rats for myocardial remodeling studies. Obese rats had abnormal myocardial structure, diastolic dysfunction, greatly elevated cardiac apoptosis, enhanced cardiac fibrosis, and increased oxidative stress level. ELISA detected significantly higher than circulating leptin level in PAT of obese, but not lean, rats. Western blot and immunohistochemical analyses demonstrated increased leptin receptor density in obese hearts. H9c2 cardiomyoblasts, after being exposed to PAT-conditioned medium of obese rats, exhibited pronounced reactive oxygen species-mediated apoptosis, which was partially reversed by leptin antagonist. Moreover, leptin derived from PAT of obese rats inhibited Na+/K+-ATPase activity of H9c2 cells through stimulating reactive oxygen species, thereby activating calcium-dependent apoptosis. Pretreatment with specific inhibitors revealed that Janus kinase 2/signal transducer and activator of transcription 3 and phosphoinositide 3-kinase/protein kinase B signaling pathways were involved in leptin-induced myocardial apoptosis. Conclusions PAT-derived leptin induces myocardial apoptosis in high-fat diet-induced obese rats via activating Janus kinase 2/signal transducer and activator of transcription 3/reactive oxygen species signaling pathway and inhibiting its downstream Na+/K+-ATPase activity.

3.
Anal Chim Acta ; 1178: 338811, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34482872

RESUMO

Capillary gel electrophoresis is widely applied for determination of sequence and size of DNA, in which the sieving gel plays an unignorable role. Herein, a pore-size controllable hydrogel was synthesized in the capillary with two symmetrical tetrahedron-like macromonomers consisting of pentaerythritoltetra (succinimidylcarboxypentyl) polyoxyethylene (PS) and pentaerythritoltetra (aminopropyl) polyoxyethylene) (PA). By capillary electrophoresis of the DNA fragments with this hydrogel, it is found that a homogenous structure of hydrogel which is more suitable for the DNA separation can be achieved when the molecular weight of PA is approximate to that of PS. DNA fragments smaller than 1500 bp can be well resolved in this hydrogel within 13 min. More than 100 consecutive runs can be carried out in such a dynamically coated capillary before performance begins to degrade. Notably, such hydrogel can realize separation of dsDNA up to single base pair resolution and same length of dsDNA with 1 bp difference.


Assuntos
Hidrogéis , Polietilenoglicóis , DNA , Eletroforese Capilar , Peso Molecular
4.
JCI Insight ; 6(17)2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34494554

RESUMO

The migrating keratinocyte wound front is required for skin wound closure. Despite significant advances in wound healing research, we do not fully understand the molecular mechanisms that orchestrate collective keratinocyte migration. Here, we show that, in the wound front, the epidermal transcription factor Grainyhead like-3 (GRHL3) mediates decreased expression of the adherens junction protein E-cadherin; this results in relaxed adhesions between suprabasal keratinocytes, thus promoting collective cell migration and wound closure. Wound fronts from mice lacking GRHL3 in epithelial cells (Grhl3-cKO) have lower expression of Fascin-1 (FSCN1), a known negative regulator of E-cadherin. Assay for Transposase-Accessible Chromatin using sequencing (ATAC-seq) on wounded keratinocytes shows decreased wound-induced chromatin accessibility near the Fscn1 gene in Grhl3-cKO mice, a region enriched for GRHL3 motifs. These data reveal a wound-induced GRHL3/FSCN1/E-cadherin pathway that regulates keratinocyte-keratinocyte adhesion during wound-front migration; this pathway is activated in acute human wounds and is altered in diabetic wounds in mice, suggesting translational relevance.

5.
BMC Pulm Med ; 21(1): 279, 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34479523

RESUMO

BACKGROUND: Dyskeratosis congenita (DC) is a rare genetic disorder of poor telomere maintenance. Pulmonary fibrosis (PF) related to DC is rarely reported. CASE PRESENTATION: A 23-year-old student presented with a four-year history of progressive cough and exertional dyspnea. Physical examination was remarkable for typical mucocutaneous abnormalities. Chest computerized tomography scan revealed interstitial fibrosis. Testing of peripheral blood leukocytes confirmed that his telomeres were 30th percentile of age-matched controls. A heterozygous missense mutation located in exon 22 of PARN gene was identified in the patient by whole exome sequencing. The patient refused danazol therapy and lung transplantation, and died of respiratory failure 2 years later. In addition, this case and 26 reported cases of DC-related PF identified through the comprehensive search of PubMed, Web of Science, WANFANG and CNKI were reviewed. Later-onset PF was observed in 11 patients (40.7%). Radiological usual interstitial pneumonia (UIP) pattern or possible UIP pattern was noted only in half of patients. However, histopathological UIP or probable UIP patterns were found in 63.6% of patients. Age at bone marrow failure (BMF) and the frequency of normal to mild thrombocytopenia in later-onset patients was significantly higher than in early-onset patients (p = 0.017 and p = 0.021, respectively). Age at PF and age at BMF in DC patients with TERC/TERT variants was significantly higher than in those with TINF2 variants or DKC1/NHP2 variants (p = 0.004 and p = 0.003, respectively). The patients with TERT/TERC/RTEL1/PARN variants had a significantly better transplant-free survival than those with TINF2 variants or DKC1/NHP2 variants (p < 0.05). Patients who underwent surgical lung biopsy had significantly worse transplant-free survival than those without lung biopsy (p = 0.042). Worse survival was found in patients with immunosuppression therapy than in those without (p = 0.012). CONCLUSIONS: It is common for DC-associated PF to occur later in life without significant hematological manifestations. Mutations in the genes encoding different components of the telomere maintenance pathway were associated with clinical phenotypes and prognosis. PF caused by DC should be kept in mind by clinicians in the differential diagnosis of patients with unexplained PF and should be excluded before diagnostic surgical lung biopsy is undertaken or empirical immunosuppression therapy is prescribed.

6.
Elife ; 102021 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-34491895

RESUMO

Inducible regulatory T (iTreg) cells play a central role in immune suppression. As iTreg cells are differentiated from activated T (Th0) cells, cell metabolism undergoes dramatic changes, including a shift from fatty acid synthesis (FAS) to fatty acid oxidation (FAO). Although the reprogramming in fatty acid metabolism is critical, the mechanism regulating this process during iTreg differentiation is still unclear. Here we have revealed that the enzymatic activity of ATP-citrate lyase (ACLY) declined significantly during iTreg differentiation upon transforming growth factor ß1 (TGFß1) stimulation. This reduction was due to CUL3-KLHL25-mediated ACLY ubiquitination and degradation. As a consequence, malonyl-CoA, a metabolic intermediate in FAS that is capable of inhibiting the rate-limiting enzyme in FAO, carnitine palmitoyltransferase 1 (CPT1), was decreased. Therefore, ACLY ubiquitination and degradation facilitate FAO and thereby iTreg differentiation. Together, we suggest TGFß1-CUL3-KLHL25-ACLY axis as an important means regulating iTreg differentiation and bring insights into the maintenance of immune homeostasis for the prevention of immune diseases.

7.
Chem Asian J ; 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34467668

RESUMO

The development of highly efficient non-precious metal catalysts for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) is key for large-scale hydrogen evolution through water splitting technology. Here, we report an air-stable Cu-based nanostructure consisting of Mn doped CuCl and CuO (CuCl/CuO(Mn)-NF) as a dual functional electrocatalyst for water splitting. CuCl is identified as the main active component, together with Mn doping and the synergistic effect between CuCl and CuO are found to make responsibility for the excellent OER and HER catalytic activity and stability. The assembled electrolyzes also exhibit decent water splitting performance. This work not only provides a simple method for preparing Cu-based composite catalyst, but also demonstrates the great potential of Cu-based non-noble metal electrocatalysts for water splitting and other renewable energy conversion technologies.

8.
Nat Commun ; 12(1): 5494, 2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34535661

RESUMO

Sessile plants encode a large number of small peptides and cell surface-resident receptor kinases, most of which have unknown functions. Here, we report that the Arabidopsis receptor kinase MALE DISCOVERER 1-INTERACTING RECEPTOR-LIKE KINASE 2 (MIK2) recognizes the conserved signature motif of SERINE-RICH ENDOGENOUS PEPTIDEs (SCOOPs) from Brassicaceae plants as well as proteins present in fungal Fusarium spp. and bacterial Comamonadaceae, and elicits various immune responses. SCOOP signature peptides trigger immune responses and altered root development in a MIK2-dependent manner with a sub-nanomolar sensitivity. SCOOP12 directly binds to the extracellular leucine-rich repeat domain of MIK2 in vivo and in vitro, indicating that MIK2 is the receptor of SCOOP peptides. Perception of SCOOP peptides induces the association of MIK2 and the coreceptors SOMATIC EMBRYOGENESIS RECEPTOR KINASE 3 (SERK3) and SERK4 and relays the signaling through the cytosolic receptor-like kinases BOTRYTIS-INDUCED KINASE 1 (BIK1) and AVRPPHB SUSCEPTIBLE1 (PBS1)-LIKE 1 (PBL1). Our study identifies a plant receptor that bears a dual role in sensing the conserved peptide motif from phytocytokines and microbial proteins via a convergent signaling relay to ensure a robust immune response.

9.
Stroke ; : STROKEAHA120032989, 2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34538087

RESUMO

BACKGROUND AND PURPOSE: This study tests whether patients with unruptured intracranial aneurysm who underwent stent placement benefitted from platelet function monitoring-guided adjustment of antiplatelet therapy. METHODS: We conducted a randomized, open-label, parallel group, assessor-blinded trial. Patients with unruptured intracranial aneurysm who underwent stent placement were assigned in a 1:1 ratio to receive either drug adjustment (patients who had high on-treatment platelet reactivity to antiplatelet therapy on the basis of platelet function monitoring [monitoring group]) or conventional therapy (without monitoring and drug adjustment [conventional group]). The second monitoring was performed 14 days after randomization in patients with drug adjustment. The primary outcome was the composite frequency of ischemic stroke, transient ischemic attack, stent thrombosis, urgent revascularization, and cerebrovascular death within 7 days after stent implantation. The safety outcome was the composite frequency of major, minor, or minimal bleeding within 1 month after stent implantation. RESULTS: In total, 314 patients were included (n=157 per group). The primary combined outcome occurred in 19 patients (12.1%) in the conventional group and 8 patients (5.1%) in the monitoring group (hazard ratio, 0.39 [95% CI, 0.17-0.92]; P=0.03). Ischemic stroke occurred at a lower frequency in the monitoring group compared with that in the conventional group (4.5% versus 12.1%; hazard ratio, 0.34 [95% CI, 0.14-0.83]; P=0.01), which drove the overall primary combined outcome. The safety outcome occurred in the monitoring group (7.0%) and in the conventional group (1.9%; hazard ratio, 3.87 [95% CI, 1.06-14.14]; P=0.03). A significant difference was observed in the frequency of minor or minimal bleeding events between the two groups (monitoring group versus conventional group, 6.4% versus 1.3%; P=0.02) but not in the frequency of major bleeding events between the two groups. CONCLUSIONS: Platelet function monitoring-guided antiplatelet therapy reduces thromboembolic events in patients with unruptured intracranial aneurysm after stent placement, significantly enhancing minor or minimal bleeding events but not major bleeding events. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03989557.

10.
J Org Chem ; 2021 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-34541854

RESUMO

The ligand-regulated regiodivergent hydroarylation of the distal double bond of allenamides with aryl boronic acid was achieved in the presence of palladium(II) catalysts, delivering a variety of functionalized enamide with excellent E selectivity and Markovnikov/anti-Markovnikov selectivity. Two possible coordination intermediates were proposed to be responsible for the regiodivergent hydroarylation: (1) The coordination Intermediate I, which was proposed to be formed through the coordination of MeCN, distal double bond, phenyl to palladium, led to the aryl group away from the Intermediate I, inducing excellent E selectivity and anti-Markovnikov selectivity. (2) A switch of regioselectivity to 1,2-Markovnikov hydroarylation was obtained using bidentate phosphine ligand (dppf or Xantphos). The formed coordination Intermediate II led to the N-tether away from the Intermediate II and at the trans position of aryl, resulting in excellent E selectivity and Markovnikov selectivity. Meanwhile, tentative investigation on the mechanism proved that the hydron source of this hydroarylation is more likely to be boronic acid. The transmetallation between aryl boronic acid and palladium catalyst was the initial step of this transformation.

11.
Sci Total Environ ; 803: 149700, 2021 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-34487901

RESUMO

The Eurasian steppe is the largest steppe region in the world and is an important part of the global grassland ecosystem. The eastern Eurasian steppe has favorable hydrothermal conditions and has the highest productivity and the richest biodiversity. Located in the arid and semi-arid region, the eastern Eurasian steppe has experienced large-scale grassland degradation due to dramatic climate change and intensive human activities during the past 20 years. Hence, accurate estimation of aboveground biomass (AGB, gC m-2) and belowground biomass (BGB, gC m-2) is necessary. In this study, plenty of AGB and BGB in-situ measurements were collected among dominated grassland types during summer in 2013 and 2016-2018 in the eastern Eurasian steppe. Vegetation indices from the Moderate Resolution Imaging Spectroradiometer (MODIS), Digital Elevation Model (DEM) and climate variables were chosen as independent variables to establish predictive models for AGB and BGB with random forest (RF). Both AGB (R2 = 0.47, MAE = 21.06 gC m-2, and RMSE = 27.52 gC m-2) and BGB (R2 = 0.44, MAE = 173.02 gC m-2, and RMSE = 244.20 gC m-2) models showed acceptable accuracy. Then the RF models were applied to generate spatially explicit AGB and BGB estimates for the study area over the last two decades (2000-2018). Both AGB and BGB showed higher values in the Greater Khingan Mountains and decreased gradually to the east and west sides. The mean values for AGB and BGB were 62.16 gC m-2 and 531.35 gC m-2, respectively. The climatic factors were much more important in controlling biomass than anthropogenic drivers, and shortage of water and raising temperature were the main limiting factor of AGB and BGB, respectively, in the peak growth season. These findings provide scientific data for the scientific management of animal husbandry and can contribute to the sustainable development of grassland ecology in the eastern Eurasian steppe.

12.
Biochem Biophys Res Commun ; 576: 1-6, 2021 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-34474244

RESUMO

Wnt signaling is one of the major signaling pathways that regulate cell differentiation, tissue patterning and stem cell homeostasis and its dysfunction causes many human diseases, such as cancer. It is of tremendous interests to understand how Wnt signaling is regulated in a precise manner both temporally and spatially. Naked cuticle (Nkd) acts as a negative-feedback inhibitor for Wingless (Wg, a fly Wnt) signaling in Drosophila embryonic development. However, the role of Nkd remains controversial in later fly development, particularly on the canonical Wg pathway. In the present study, we show that nkd is essential for wing pattern formation, such that both gain and loss of nkd result in the disruption of Wg target expression in larvae stage and abnormal adult wing morphologies. Furthermore, we demonstrate that a thirty amino acid fragment in Nkd, identified previously in Wharton lab, is critical for the canonical Wg signaling, but is dispensable for Wg/planar cell polarity pathway. Putting aside the pleiotropic nature of nkd function, i.e. its role in the Decapentaplegic signaling, we conclude that Nkd universally inhibits the canonical Wg pathway across a life span of Drosophila development.

13.
Cell Metab ; 33(9): 1717-1718, 2021 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-34496226

RESUMO

Glucocorticoid resistance often dims glucocorticoid's therapeutic efficacy in sepsis. However, the mechanism is incompletely understood. In this issue, Vandewalle et al. (2021) demonstrate that glucocorticoid resistance leads to hyperlactatemia and that this combination facilitates lethal sepsis. This insight gives important clarity to the pathophysiology of sepsis, while further suggesting therapeutic avenues for its treatment.

14.
Environ Pollut ; 290: 118042, 2021 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-34523509

RESUMO

Contaminant adsorption by microplastics (MPs) allows them to act as contaminant vehicles or vectors, complicating eco-toxicological study of MPs. The contaminants adsorbed are mainly organic contaminants, especially hydrophobic organic contaminants (HOCs), although heavy-metal adsorption has also been reported. Compared to the mechanisms of HOC adsorption, those for metals are not fully understood. In the present study, combined-exposure assays revealed that polyethylene microplastics (PEMPs, 150 µm) alleviate the toxic effect of nano zinc oxide (nZnO, 20-30 nm) on marine microalgal growth by 14.4%. Thus, we hypothesized that nZnO adsorption onto PEMP surfaces ameliorates its toxicity to microorganisms. To test this hypothesis, PEMP samples isolated from nZnO suspensions were characterized. Their surfaces were observed by SEM, their Zn levels were measured by ICP-MS, and the compound form of Zn on the PEMP surface was determined by XRD analysis. The results indicated that 5.53%-7.16% of the Zn in the suspension is adsorbed during the first 24 h of exposure and that the Zn remains as the ZnO form upon adsorption. The findings in the present study provide important information on the role of MPs as metal oxide vehicles.

15.
Bioengineered ; 12(1): 5552-5565, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34517782

RESUMO

Ischemic heart disease in children may be induced by varied factors, and there is no corresponding systematic treatment up to now. This study aims to investigate the effects of microRNA (miR)-148 on myocardial injury in immature rats with myocardial ischemia-reperfusion (MI/R) injury. In this study, MI/R model was established by ligating the coronary artery of heart. The results showed that miR-148 alleviated myocardial injury and rescued relevant parameters (mean ventricular systolic blood pressure (MAP), left ventricular systolic blood pressure (LVSP), heart rate (HR), creatine kinase-MB (CK-MB), cTn1 and Mb in immature rats with MI/R injury. Besides, miR-148 improved the immune dysfunction induced by MI/R through increasing the number of interleukin (IL)-10+ cells and reducing the number of inducible nitric oxide synthase (iNOS)+ cells. In addition, miR-148 relieved the apoptosis of cardiomyocytes induced by MI/R through inhibiting the expression of Bax and elevating the expression of Bcl-2. Further molecular mechanism indicated that pyruvate dehydrogenase kinase 4 (PDK4) was the downstream target of miR-148, which was further confirmed by dual luciferase reporter assay and related expression detection. Accordingly, silenced PDK4 attenuated cardiac dysfunction, immune disorder and myocardial apoptosis in immature rats and enhanced the ability of antioxidant enzymes. What is more, activated SMAD pathway induced by MI/R injury was then blocked by silenced PDK4. Taken together, our study demonstrated that overexpressed miR-148 relieved cardiac dysfunction, immune disorder and cardiomyocyte apoptosis in immature MI/R rats by PDK4 inhibition, which provided novel targets for MI/R injury treatment.

16.
Bioengineered ; 12(1): 6229-6239, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34519258

RESUMO

Recently, circular RNAs (circRNAs) have become an intense focus of research and large numbers of circRNAs have been identified, awaiting functional elucidation. Thus, the present study aims to examine the regulation of circRNAs and its molecular mechanism in lung cancer growth. Here, we show that circular RNA circ_0000677 was overexpressed and correlated with poor prognosis in non-small cell lung cancer (NSCLC) patients. Functionally, circ_0000677 knockdown markedly inhibited proliferation of NSCLC cells by observing of immunofluorescence staining of Ki67, clone formation assay, and xenograft experiments. In mechanism, circ_0000677 acted as a sponge of microRNA-106b and further regulated CCDND1 gene expression in NSCLC cells by dual luciferase activity assay and their expression examination. Taken together, these findings suggest a role for circ_0000677/miR-106b/CCND1 regulation axis in promoting NSCLC growth and progression.

17.
ACS Appl Mater Interfaces ; 13(36): 43414-43425, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34472827

RESUMO

Two-dimensional material titanium carbide (Ti3C2Tx MXene) has been widely used for building diverse functional materials; however, the disadvantages of unsatisfactory yield and low concentration during the preparation process generally limit its large-scale promotion. In the present work, an MXene dispersion with enhanced yield (90%), high concentration (45 mg/mL), and excellent dispersibility was successfully prepared. Subsequently, the active MXene nanosheets were effectively in situ deposition onto the silk fiber by means of dip-coating, relying on van der Waals forces and hydrogen bonds. The obtained MXene-decorated silk fabric (MXene@silk) exhibits satisfactory electrical conductivity (170 mS/cm), excellent photothermal and electrothermal conversion properties, especially dual-drive energy conversion, rapid thermal responses, and long-term functional stability. Furthermore, UV protection factor of the fabric, and its antibacterial efficiency against Gram-negative Escherichia coli (E. coli) within 20 min of contact reach over 110 and 99%, respectively, demonstrating remarkable UV resistance and rapid photothermal antibacterial ability. Meanwhile, the fabric of MXene@silk still retains the original characteristics of breathability, softness, and skin-friendly properties compared to the untreated. The multifunctional fabric constructed through a facile and high-yield strategy shows a noticeable potential applying to smart textiles to meet people's multipurpose needs in the future.

18.
ACS Appl Mater Interfaces ; 13(36): 42605-42612, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34472828

RESUMO

Transition metal borides (TMBs) are a class of important but less well-explored electrocatalytic materials for water splitting. The lack of an advanced methodology to synthesize complex nanostructured TMBs with tunable surface properties is a major obstacle to the exploration of the full potential of TMBs for electrocatalytic applications. Here, we report the facile fabrication of a cobalt foam (CF)-supported hierarchical nanostructured Co-Mo-B/CoMoO4-x composite using a hydrothermal method, followed by annealing and NaBH4 reduction treatments. Our study found that NaBH4 reduction of CoMoO4 resulted in the concurrent formation of amorphous Co-Mo-B and an O-vacancy-rich CoMoO4-x substrate, which cooperatively catalyzed the hydrogen evolution reaction (HER) in an alkaline electrolyte. The hierarchical nanoporous structure derived from the dehydration and partial reduction reactions of the CoMoO4·nH2O precursor could offer ample accessible active sites, as well as interconnected channels for rapid mass transfer. In addition, the in situ growth of electrically conductive Co-Mo-B nanoparticles on the defective structured CoMoO4-x substrate imparted the electrocatalyst with good electrical conductivity. As a result, the Co-Mo-B/CoMoO4-x/CF catalyst showed impressively high activity and outstanding stability for the alkaline HER, outperforming most reported TMB electrocatalysts. For instance, it required an overpotential of 55 mV to afford 10 mA·cm-2 and showed a fluctuation of only ±8 mV in a 100 h constant-current test at 100 mA·cm-2.

19.
Brain Res Bull ; 2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34534636

RESUMO

BACKGROUND: The kinase MST4 limits inflammatory responses through direct phosphorylation of the adaptor TRAF6. TRAF6 interacted with NLRP3 to promote the activation of NLRP3 inflammasome. However, the role of MST4 on neuroinflammation after intracerebral hemorrhage (ICH), and how it interacts with NLRP3 inflammasome, remains unclear. METHODS: Mice were administrated with MST4 AAV four weeks before collagenase-induced ICH. ICH mice received either hesperadin (MST4 selective inhibitor), or MCC950 (NLRP3 inflammasome selective inhibitor). Neurological deficits and brain water content were assessed. Western blot and immunofluorescence were performed to evaluate the proteins content and localization in MST4/NLRP3 signaling pathway. RESULTS: The expression of endogenous MST4 and NLRP3 was increased after ICH compared to sham group. MST4 and NLRP3 were respectively colocalized in microglia. Upregulation of MST4 gene inhibited the activation of NLRP3 inflammasome, the release of IL-1ß and TNF-α, and significantly improved brain edema and neurological deficits. Hesperadin pretreatment inhibited the expression of MST4 and increased the expression of NLRP3 inflammasome-medicated proteins, which aggravated neurological deficits and cerebral edema. MCC950 markedly alleviated neurological deficits, brain edema while had no effect on the expression of MST4 protein. CONCLUSIONS: MST4 alleviates inflammatory progression and brain injury in ICH mice possibly by inhibiting NLRP3 inflammasome activation.

20.
Arch Virol ; 2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34535823

RESUMO

The entomopathogenic fungus Beauveria bassiana is used worldwide for biological control of insects. Seven dsRNA segments were detected in a single B. bassiana strain, RCEF1446. High-throughput sequencing indicated the presence of three mycoviruses in RCEF1446. Two were identified as the known mycoviruses Beauveria bassiana victorivirus 1 and Beauveria bassiana polymycovirus 1, and the novel mycovirus was designated as "Beauveria bassiana bipartite mycovirus 1" (BbBV1). The complete sequence of the BbBV1 is described here. The mycovirus contains two dsRNA segments. The RNA 1 (dsRNA 4) of BbBV1 is 2,026 bp in length, encoding a RNA-dependent RNA polymerase (RdRp) (68.54 kDa), while the RNA 2 (dsRNA 6) is 1,810 bp in length, encoding a hypothetical protein (35.55 kDa) with unknown function. Moreover, the amino acid sequence of RdRp showed the highest sequence identity of 62.31% to Botryosphaeria dothidea bipartite mycovirus 1. Phylogenetic analysis based on RdRp sequences revealed that BbBV1 represents a distinct lineage of unassigned dsRNA mycoviruses infecting fungi.

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