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1.
Appl Opt ; 60(31): 9981-9988, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34807189

RESUMO

A completely non-blocking M×N electrically controlled optofluidic matrix switch that uses a 1×3 optical switch with a V-shaped microchannel as the switching unit is proposed. Its light paths and output ports are selected by a micro-actuator matrix and a control circuit. There are few reports of optofluidic matrix switches. Here the given electrostatic micro-actuator and the basic switch structure provide an effective feasible manner for the matrix switch due to the simple and compact structure as well as the operation style. The impacts of microchannels and intersecting waveguides on the switch performance are discussed, and multiple optimization schemes are proposed to reduce the insertion loss efficiently and significantly. The research results indicate that the M×N matrix switch has the advantages of good matrix controllability, simple structure, wide waveband (400-1700 nm), negligible polarization-dependent loss, small insertion loss, and low cross talk. For 1550 nm wavelength, the insertion loss of a 2×6 matrix switch is about 0.17-0.55 dB, and the maximum cross talk is less than -26.8dB. In addition, the performance parameters of a 4×8 matrix switch are given and compared with other reported matrix switches. The proposed M×N matrix switch solves the problem of large insertion loss of general optical matrix switches and can be expanded to a large-scale matrix switch. Moreover, the design of multiple output ports has more flexible applications in systems with multiple branch optical paths and network nodes.

2.
BMC Endocr Disord ; 21(1): 231, 2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34794397

RESUMO

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) and gallstone disease (GSD) often coexist in the general population owing to shared risk factors. This study explored the relationship between NAFLD and GSD in patients with type 2 diabetes. METHODS: We conducted a retrospective cross-sectional analysis of 4325 patients with type 2 diabetes. GSD and NAFLD were confirmed using ultrasonography. GSD was defined as either asymptomatic gallstones or previous cholecystectomy, and each was analyzed separately. RESULT: There was no significant difference in the prevalence of GSD between patients with and without NAFLD (23.8% vs. 21.2%, P = 0.15). After case-control matching (1:1) of baseline data such as age, sex, duration of diabetes, and HbA1c between patients with and without NAFLD, there was still no significant difference in the prevalence of GSD (25.5% vs. 23.6%, P = 0.15). The prevalence of NAFLD in patients with asymptomatic gallstones was lower than that of patients without GSD (38.6% vs. 47.3%, P < 0.001), whereas the prevalence in those who had undergone cholecystectomy was much higher (61.2% vs. 47.3%, P < 0.001). The ratio of cholecystectomy to asymptomatic gallstone in patients with or without NAFLD was 1.97 and 0.79, respectively. The rate of cholecystectomy was higher in the patients with NAFLD than in those without NAFLD (15.8% vs. 9.3%, P < 0.001), consistent with the result after case-control matching (17.3% vs. 11.2%, P < 0.001). Multivariate logistic regression analysis, after adjusting for numerous potential confounding factors, revealed that GSD (OR = 1.241, 95%CI: 1.036-1.488, P = 0.002) and cholecystectomy (OR = 1.946, 95%CI: 1.546-2.445, P < 0.001) were both strongly associated with NAFLD. However, asymptomatic gallstone (OR = 0.663, 95%CI: 0.513-0.856, P = 0.002) seemed to be negatively correlated with NAFLD. CONCLUSIONS: The prevalence of GSD was similar in patients with type 2 diabetes with and without NAFLD. The higher proportion of cholecystectomy and lower proportion of asymptomatic gallstones in patients with NAFLD suggests that NAFLD may increase the risk of complications of GSD.

3.
Artigo em Inglês | MEDLINE | ID: mdl-34760019

RESUMO

Fructus Gleditsiae Abnormalis (FGA) has been used as a traditional Chinese medicine (TCM) for the treatment of stroke caused by phlegm and blood stasis. However, its substance basis and mechanism of action are currently unknown. This study is aimed to analyze the constituents of the volatile oil in FGA (VOFGA) using gas chromatography coupled with mass spectrometry (GC-MS) and explore the underlying effects and mechanisms of VOFGA in the prevention and treatment of ischemia stroke. An in vivo ischemia model was constructed by combination treatment of high-fat diet (HFD) and middle cerebral artery occlusion (MCAO) method. After administration, the cerebral infarction volume, the brain water content, hemorheology, blood lipids, inflammatory factors, oxidative stress indicators, Bax, Bcl-2, and cleaved caspase-3 and histological examination (HE) were determined and observed to explore the underlying effects and mechanisms of VOFGA against ischemia stroke. The results showed that forty components were determined after analyzed by GC-MS, and the percentage content of palmitate, paeonol, violetone, linalool, salpinol, citral, and methyleugenol were 4.69%, 5.2%, 3.56%, 3.31%, 2.42%, 2.65%, and 1.67%, respectively. The high dose of VOFGA could inhibit neurological damage; reduce the cerebral infarction volume and brain water content; improve whole blood viscosity and red blood cell aggregation index at various shear rates; reduce the levels of TG, TC, LDL-C, TNF-α, IL-1ß, MDA, and NO; increase the contents of HDL-C, IL-10, and SOD; downregulate the expressions of Bax and cleaved caspase-3 in the ischemic regions; and upregulate the expressions of Bcl-2. These effects implied that VOFGA may exert neuroprotective effects via inhibiting ischemia-triggered oxidative damage-regulating blood lipid factors and reducing the production of proinflammatory mediators against cerebral I/R injury and neuronal apoptosis. The VOFGA presents a potential treatment value for cerebral ischemic stroke, and it may offer insights into discovering new active compounds for the treatment of ischemic stroke.

4.
BMJ Open ; 11(10): e043790, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34598979

RESUMO

OBJECTIVES: As early prediction of severe illness and death for patients with coronavirus disease 2019 (COVID-19) is important, we aim to explore the clinical value of laboratory indicators in evaluating the progression and prognosis of patients with COVID-19. DESIGN: Retrospective cohort study. SETTING: Hospital-based study in China. PARTICIPANTS: Adult patients with COVID-19 from December 15, 2019 to March 15, 2020. END POINT: Disease severity and mortality. METHODS: Clinical data of 638 patients with COVID-19 were collected and compared between severe and non-severe groups. The predictive ability of laboratory indicators in disease progression and prognosis of COVID-19 was analysed using the receiver operating characteristic curve. The survival differences of COVID-19 patients with different levels of laboratory indicators were analysed utilising Kaplan-Meier analysis. RESULTS: 29.8% (190/638) of patients with COVID-19 progressed to severe. Compared with patients with no adverse events, C reactive protein (CRP), neutrophil-to-lymphocyte ratio (NLR) and D-dimer were significantly higher in severe patients with adverse events, such as acute myocardial injury, respiratory failure, acute kidney injury, mechanical ventilation, intensive care unit admission, multiple organ dysfunction syndromes and death (all p<0.05). The multivariate logistic analysis suggested that CRP, NLR and D-dimer were independent risk factors for the disease progression of COVID-19 (all p<0.05). The model combining all of them owned the highest area under the receiver operating characteristic curve (AUC) predicting disease progression and death of COVID-19, with AUC of 0.894 (95% CI 0.857 to 0.931) and 0.918 (95% CI 0.873 to 0.962), respectively. Survival analysis suggested that the patients with a high level of CRP, NLR or D-dimer performed shorter overall survival time (all p<0.05). CONCLUSIONS: The combination of CRP, NLR and D-dimer could be an effective predictor for the aggravation and death in patients with COVID-19. The abnormal expression of these indicators might suggest a strong inflammatory response and multiple adverse events in patients with severe COVID-19.


Assuntos
COVID-19 , Laboratórios , Adulto , Progressão da Doença , Humanos , Neutrófilos , Prognóstico , Curva ROC , Estudos Retrospectivos , SARS-CoV-2
6.
Front Cell Dev Biol ; 9: 727286, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34631710

RESUMO

Objective: In this study, we mainly explored two questions: Which microorganisms were functionally active in the endometrium of patients with endometrial cancer (EC)? What kind of response did the human host respond to functionally active microorganisms? Methods: Nine endometrial cancer patients and eight normal subjects were included in this study. HMP Unified Metabolic Analysis Network 3 (HUMAnN3) was used to obtain functional information of microorganisms. In addition, metaCyc-based GSEA functional enrichment analysis was used to obtain information on the metabolic pathways of the human host. At the same time, the O2PLS model and Spearman correlation analysis were used to analyze the microorganisms-host interaction. Results: With the novel metatranscriptome analysis pipeline, we described the composition of more than 5,000 functionally active microorganisms and analyzed the difference in microorganisms between the EC and the normal group. Our research found that these microorganisms were involved in part of the metabolic process of endometrial cancer, such as 6-sulfo-sialyl Lewis x epitope, N-acetyl-beta-glucosaminyl. In addition, the host-microbiota crosstalk of EC endometrium also included many biological processes, mainly functions related to tumor migration and the Apelin signaling pathway. Conclusion: The functionally active microorganisms in the EC endometrium played an essential role in the occurrence and migration of tumors. This meant that functionally active microorganisms could not be ignored in the treatment of endometrial cancer. This study helped to better understand the possible role of endometrial functional, active microorganisms in the occurrence and development of EC in patients with endometrial cancer and provided new information for new attempts to treat EC.

7.
Nat Commun ; 12(1): 5953, 2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34642325

RESUMO

Triggered by the pioneering research on graphene, the family of two-dimensional layered materials (2DLMs) has been investigated for more than a decade, and appealing functionalities have been demonstrated. However, there are still challenges inhibiting high-quality growth and circuit-level integration, and results from previous studies are still far from complying with industrial standards. Here, we overcome these challenges by utilizing machine-learning (ML) algorithms to evaluate key process parameters that impact the electrical characteristics of MoS2 top-gated field-effect transistors (FETs). The wafer-scale fabrication processes are then guided by ML combined with grid searching to co-optimize device performance, including mobility, threshold voltage and subthreshold swing. A 62-level SPICE modeling was implemented for MoS2 FETs and further used to construct functional digital, analog, and photodetection circuits. Finally, we present wafer-scale test FET arrays and a 4-bit full adder employing industry-standard design flows and processes. Taken together, these results experimentally validate the application potential of ML-assisted fabrication optimization for beyond-silicon electronic materials.

8.
Front Oncol ; 11: 667655, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34568007

RESUMO

Purpose: To characterize clinical features and identify baseline prognostic factors for survival in young adults with advanced gastric cancer (YAAGC). Materials and Methods: A total of 220 young inpatients (age less than or equal to 40 years) with an initial diagnosis of advanced gastric cancer were retrospectively enrolled in this study. Results: Of a consecutive cohort of 220 patients with YAAGC, the median overall survival (OS) time was 16.3 months. One-year survival rate was 43.6% (95% CI: 36.5 to 50.7). In this cohort, a female (71.4%, n = 157) predominance and a number of patients with poorly differentiated tumors (95.9%, n = 211) were observed. In the univariate analysis, OS was significantly associated with neutrophil-lymphocyte ratio (NLR) (≥3.12), hypoproteinemia (<40 g/L), presence of peritoneal or bone metastases, and previous gastrectomy of primary tumor or radical gastrectomy. In multivariate Cox regression analysis, hypoproteinemia [hazard ratio (HR) 1.522, 95% CI 1.085 to 2.137, p = 0.015] and high NLR level (HR 1.446, 95% CI 1.022 to 2.047, p = 0.021) were two independent poor prognostic factors, while previous radical gastrectomy was associated with a favorable OS (HR 0.345, 95% CI 0.205 to 0.583, p = 0.000). A three-tier prognostic index was constructed dividing patients into good-, intermediate-, or poor-risk groups. Median OS for good-, intermediate-, and poor-risk groups was 36.43, 17.87, and 11.27 months, respectively. Conclusions: Three prognostic factors were identified, and a three-tier prognostic index was devised. The reported prognostic index may aid clinical decision-making, patient risk stratification, and planning of future clinical studies on YAAGC.

9.
Histol Histopathol ; : 18372, 2021 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-34486677

RESUMO

Long noncoding RNAs (lncRNAs) are the most recently discovered class of noncoding RNAs. LncRNAs play a crucial role in multiple disorders. However, the role and mechanism of action of lncRNAs in keloids remain unclear. Here, qRT-PCR and western blotting assays were performed to determine the expression of genes and proteins, respectively. MTT assays were carried out to measure the proliferation of keloid fibroblasts. In addition, a luciferase activity assay was conducted to investigate the relationships between LINC00937 and miR-28-5p and between miR-28-5p and MC1R. The results showed that LINC00937 and MC1R were decreased, whereas miR-28-5p was increased in keloid tissues. LINC00937 overexpression in keloid fibroblasts could repress the extracellular matrix (ECM) deposition and cell proliferation and promote MC1R expression. Moreover, high expression of miR-28-5p and low expression of LINC00937 were detected in keloid fibroblasts. We further showed that LINC00937 promoted MC1R expression by sponging miR-28-5p. Finally, our data indicated that LINC00937 inhibited the ECM deposition and proliferation of keloid fibroblasts by inhibiting miR-28-5p and facilitating MC1R expression. Overall, LINC00937 suppressed the ECM deposition and proliferation of keloid fibroblasts by acting as an miR-28-5p sponge and promoting MC1R expression. Our data suggested that LINC00937 is a potential target for keloid treatment.

10.
Macromol Rapid Commun ; 42(21): e2100460, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34505728

RESUMO

Polymer/graphene oxide (GO) composites, which combine the physical properties of GO and the processability of polymers, are of increasing interest in a variety of applications ranging from conductive foams, sensors, to bioelectronics. However, the preparation of these composites through physical blending demands the polymers with functional groups that interact strongly with the GO. Here the design and synthesis of a new bifunctional reversible addition-fragmentation chain transfer (RAFT) agent are demonstrated, which allows the synthesis of polymers with predetermined molecular weights and low dispersibilities (Ð), while having functionalities at both polymer termini that allow strong binding to GO. To access polymers with diverse thermal and mechanical properties, acrylonitrile-styrene-acrylate (ASA) copolymers with different types of acrylates, both short and long side chains, are synthesized under the control of the bifunctional RAFT agent. Furthermore, the strong binding between GO and the synthesized polymers is verified and explored to prepare polymer/GO composites with diverse tensile strengths and conductivity in the range of semiconductors. Overall, this novel RAFT agent is expected to expand the utility of polymer/GO composites by providing well-defined polymers with tunable properties and strong binding with GO.


Assuntos
Grafite , Polímeros , Peso Molecular , Estireno
11.
Dalton Trans ; 50(32): 11221-11227, 2021 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-34338702

RESUMO

In this work, we present a brand-new narrowband red-emitting fluoroperovskite via the introduction of Mn4+ into NaZnF3 through a facile co-precipitation method at room temperature. The physicochemical properties of the fluoroperovskite such as crystal and electronic structures, morphology, and elemental composition, as well as its spectroscopic properties such as luminescence behaviours and optical performance were characterized and investigated in detail. Evidence shows that NaZnF3:Mn4+ exhibits a uniform particulate shape with single-phase crystallinity. By virtue of the non-equivalent substitution and the [MnF6] octahedral distortion in the fluoride host, sharp red emissions of phonon sidebands and the zero-phonon line upon blue light excitation are identified. Benefiting from the unique spectral feature, a wide colour gamut of 104.1% NTSC is achieved by coating ß-SiAlON:Eu2+ and NaZnF3:Mn4+ on an InGaN chip, indicating the potential use of the Mn4+ fluoroperovskite as a colour converter for display backlight application.

12.
Cell Mol Biol Lett ; 26(1): 37, 2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34399682

RESUMO

BACKGROUND: Iron overload can promote the development of osteoporosis by inducing apoptosis in osteoblasts. However, the mechanism by which miRNAs regulate apoptosis in osteoblasts under iron overload has not been elucidated. METHOD: The miRNA expression profile in MC3T3-E1 cells under iron overload was detected by next generation sequencing. qRT-PCR was used to determine the expression of miR-3074-5p in MC3T3-E1 cells under iron overload. The proliferation of MC3T3-E1 cells was tested using CCK-8 assays, and apoptosis was measured using flow cytometry. The miRanda and TargetScan databases were used to predict the target genes of miR-3074-5p. Interaction between miR-3074-5p and the potential target gene was validated by qRT-PCR, luciferase reporter assay and western blotting. RESULTS: We found that iron overload decreased the cell viability and induced apoptosis of MC3T3-E1 cells. The results of next generation sequencing analysis showed that miR-3074-5p expression was significantly increased in MC3T3-E1 cells under iron overload conditions, which was confirmed by further experiments. The inhibition of miR-3074-5p attenuated the apoptosis of iron-overloaded MC3T3-E1 cells. Furthermore, the expression of Smad4 was decreased and was inversely correlated with miR-3074-5p expression, and overexpression of Smad4 partially reversed the viability inhibition of iron-overloaded MC3T3-E1 cells by relieving the suppression of ERK, AKT, and Stat3 phosphorylation, suggesting its regulatory role in the viability inhibition of iron-overloaded MC3T3-E1 cells. The luciferase reporter assay results showed that Smad4 was the target gene of miR-3074-5p. CONCLUSION: miR-3074-5p functions as an apoptosis promoter in iron-overloaded MC3T3-E1 cells by directly targeting Smad4.

13.
ACS Nano ; 2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34375086

RESUMO

The nanoscale hierarchical design that draws inspiration from nature's biomaterials allows the enhancement of material performance and enables multifarious applications. Self-assembly of block copolymers represents one of these artificial techniques that provide an elegant bottom-up strategy for the synthesis of soft colloidal hierarchies. Fast-growing polymerization-induced self-assembly (PISA) renders a one-step process for the polymer synthesis and in situ self-assembly at high concentrations. Nevertheless, it is exceedingly challenging for the fabrication of hierarchical colloids via aqueous PISA, simply because most monomers produce kinetically trapped spheres except for a few PISA-suitable monomers. We demonstrate here a sequential one-pot synthesis of hierarchically self-assembled polymer colloids with diverse morphologies via aqueous PISA that overcomes the limitation. Complex formation of water-immiscible monomers with cyclodextrin via "host-guest" inclusion, followed by sequential aqueous polymerization, provides a linear triblock terpolymer that can in situ self-assemble into hierarchical nanostructures. To access polymer colloids with different morphologies, three types of linear triblock terpolymers were synthesized through this methodology, which allows the preparation of AXn-type colloidal molecules (CMs), core-shell-corona micelles, and raspberry-like nanoparticles. Furthermore, the phase separations between polymer blocks in nanostructures were revealed by transmission electron microscopy and atomic force microscopy-infrared spectroscopy. The proposed mechanism explained how the interfacial tensions and glass transition temperatures of the core-forming blocks affect the morphologies. Overall, this study provides a scalable method of the production of CMs and other hierarchical structures. It can be applied to different block copolymer formulations to enrich the complexity of morphology and enable diverse functions of nano-objects.

14.
Nanotechnology ; 32(49)2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-34438386

RESUMO

The development of simple preparation and excellent capacity performance electrode materials is the key to energy conversion and storage for supercapacitors. Based on the growth mechanism of crystal, Zn induced NiCo nanosheets and nanoneedles composite structure deposed on Ni foam (ZNC) are successfully attained by a facile one-step method, the growth mechanism of the composite structure is further discussed. Because of its unique composites structure and additional modification of carbon, the carbon modified ZNC (ZNC@C) delivers better energy storage ability (2280 mC cm-2at 2 mA cm-2) compare to ZNC. An asymmetric supercapacitor (ASC) is assembled by ZNC@C as the positive electrode and carbonized popcorn as the negative electrode. The ASC exhibits good energy storage performance. Zn also positively affects the adsorption energy to enhance the capacitance property based on Density Functional theory calculation. The simple method for the composite structure by tuning the kinetics behaver of the crystal can provide a new strategy in synthesizing the materials, and the material with a unique structure and high performance will have potential applications in the field of energy storage.

15.
Vet Med Sci ; 7(6): 2410-2417, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34409767

RESUMO

BACKGROUND: Germinal vesicle (GV) chromatin configurations of oocytes are proposed to be related to oocyte competence and may reflect the quality of oocyte. Currently, a limited number of published studies investigated the GV chromatin configurations of guinea pig oocytes. OBJECTIVE: In this study on the in vitro maturation (IVM) of guinea pig oocytes, we examined the changes in their GV chromatin configurations during meiotic progression. METHODS: Based on the degree of chromatin compaction, the GV chromatin configurations of guinea pig oocytes could be divided into three categories depending on whether the nucleolus-like body (NLB) was surrounded or partly surrounded by compacted chromatin, namely the uncondensed (NSN), the intermediate type (SN-1) and the compacted type (SN-2). RESULTS: The percentage of cells displaying the SN-2 configuration increased with the growth of guinea pig oocytes, suggesting that this configuration presents the potential for maturation in oocytes. Oocytes derived from larger follicle exhibited increased meiotic potential. Serum starvation affected the GV chromatin configurations of guinea pig oocytes. CONCLUSIONS: Collectively, these results suggest that the SN-2 type might be a more mature form of configuration in guinea pig oocyte, whose proportion was associated with the follicle size and susceptible to the environment (e.g. serum concentration).

16.
Immun Inflamm Dis ; 9(4): 1618-1630, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34449972

RESUMO

INTRODUCTION: The prognosis of patients with glioma is dismal. It has been reported that Serpin peptidase inhibitor clade A member 3 (SERPINA3) is associated with the mobility and invasion of tumor cells. Our study was designed to explore the value of SERPINA3 messenger RNA (mRNA) expression in the biological process, prognosis, and immune significance in glioma. METHODS: We analyzed the biological functions of SERPINA3 through data from the Chinese Glioma Genome Atlas databases. Differentially expressed genes and enrichment analysis were performed and correlations between SERPINA3 expression and immune cell infiltration were analyzed. Further, we validated the expression and the survival prediction role of SERPINA3 by using tissue microarrays and RNAscope in situ hybridization in 321 gliomas. The correlations between the expression and clinical-pathological parameters as well as other biomarkers were examined. RESULTS: Univariate and multivariate regression both indicated that the level of SERPINA3 transcript represented an independent prognostic factor. High levels of SERPINA3 correlated with poor survival in patients with glioma. Expression of SERPINA3 mRNA was observed positively correlated with MCM6, IGFBP2, and FKBP10. Enrichment analysis showed SERPINA3 mainly enriched in immune-related terms and signaling pathways including MAPK, TNF, P53, PI3K-Akt, nuclear factor-κB. Immune infiltration analysis further declare the SERPINA3 expression negatively correlated with levels of Macrophages M1, native CD4+ T cell, monocytes, and Mast cell activated. And overexpression of SERPINA3 correlated with low CD4+ T cell infiltration in glioma tissues. CONCLUSIONS: SERPINA3 may play a key role in the biological process of glioma cells especially in immune suppression activities. SERPINA3 may serve as an independent survival prediction factor in glioma patients.

17.
Chem Commun (Camb) ; 57(64): 7954-7957, 2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34286749

RESUMO

Herein, we report, for the first time, a Pd6L8(NO3)5.4(ICG)6.6 (ICG = indocyanine green) cage-based hexagonal nanoplate (3) via a combined nanoprecipitation and solid-state anion-exchange approach. Nanoplate 3 possesses enhanced near-infrared (NIR) light-triggered 1O2 generation, high cellular uptake selective lysosome-targeting ability, and, consequently, excellent antineoplastic activity.


Assuntos
Antineoplásicos/farmacologia , Estruturas Metalorgânicas/farmacologia , Nanopartículas/química , Fármacos Fotossensibilizantes/farmacologia , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Raios Infravermelhos , Células MCF-7 , Estruturas Metalorgânicas/química , Estrutura Molecular , Tamanho da Partícula , Fotoquimioterapia , Fármacos Fotossensibilizantes/química
18.
Adv Sci (Weinh) ; 8(17): e2101759, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34250756

RESUMO

Renewable organic cathodes with abundant elements show promise for sustainable rechargeable batteries. Herein, for the first time, utilizing C60 fullerene as organic cathode for room-temperature lithium-ion battery is reported. The C60  cathode shows robust electrochemical performance preferably in ether-based electrolyte. It delivers discharge capacity up to 120 mAh g-1 and specific energy exceeding 200 Wh kg-1 with high initial Coulombic efficiency of 91%. The as-fabricated battery holds a capacity of 90 mAh g-1 after 50 cycles and showcases remarkable rate performance with 77 mAh g-1 retained at 500 mA g-1 . Noteworthily, three couples of unusual flat voltage plateaus recur at ≈2.4, 1.7, and 1.5 V, respectively. Diffusion-dominated three-electron-redox reactions are revealed by cyclic voltammogram and plateau capacities. Intriguingly, it is for the first time unveiled by in situ X-ray diffraction (XRD) that the C60 cathode underwent three reversible phase transitions during lithiation/delithiation process, except for the initial discharge when irreversible polymerization in between C60 nanoclusters existed as suggested by the characteristic irreversible peak shifts in both in situ XRD pattern and in situ Raman spectra. Cs-corrected transmission electron microscope corroborated these phase evolutions. Importantly, delithiation potentials derived from density-functional-theory simulation based on proposed phase structures qualitatively consists with experimental ones.

19.
Sci Total Environ ; 795: 148813, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34246134

RESUMO

The effect of pyrene on the formation of naturally Au nanoparticles (AuNPs) in the presence of humic acid (HA) under UV irradiation is described. TEM, EDS, FTIR and XPS were carried out to prove the formation of AuNPs and display their morphologies and formation mechanism. There are little differences between size, morphology and function groups of surface coated materials of AuNPs formed with and without pyrene. With the presence of HA, pyrene showed an inhibiting effect on the reduction of Au ion via competition for O2•-, thereby decreasing the production of AuNPs. However, AuNPs formed by HA-pyrene showed higher stability than AuNPs formed by HA with the sedimentation rates of 4.13% and 13.68% respectively after 30-d standing. As for the antibacterial activities against Staphylococcus aureus and Escherichia coli, AuNPs formed by HA-pyrene were more toxic than AuNPs formed by HA. Meanwhile, changes of environmental factors such as temperature, pH and ionic strength exhibited similar influence trend on the formation of AuNPs in the presence and absence of pyrene. The results suggest that the typical petroleum hydrocarbon pyrene contained in spilled oil could influence the formation, fate and ecotoxicity of AuNPs.


Assuntos
Nanopartículas Metálicas , Petróleo , Antibacterianos/toxicidade , Ouro , Nanopartículas Metálicas/toxicidade , Petróleo/toxicidade , Pirenos/toxicidade
20.
J Dermatol Sci ; 103(3): 130-134, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34238637

RESUMO

Human skin is a highly efficient self-renewing barrier that is critical to withstanding environmental insults. Undifferentiated keratinocyte stem cells reside in the basal layer of the epidermis and in hair follicles that continuously give rise to progenies ensuring epidermal turnover and renewal. Ultraviolet (UV) radiation is a proven cause of skin keratinocyte cancers, which preferentially occur at sun-exposed areas of the skin. Fortunately, melanocytes produce melanin that is packaged in specific organelles (termed melanosomes) that are then delivered to nearby keratinocytes, endowing the recipient cells with photoprotection. It has long been thought that melanosome transfer takes place stochastically from melanocytes to keratinocytes via an as-yet-unrecognized manner. However, recent studies have indicated that melanosomes are distributed regionally in the basal layer of the skin, affording localized intensive photoprotection for progenitor keratinocytes and stem cells that reside in the microenvironment of the basal epidermis. In this review, we summarize current knowledge about molecular and cellular mechanisms that are responsible for the selective transfer and exclusive degradation of melanosomes in the epidermis, emphasizing implications for skin carcinogenesis.

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