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1.
J Colloid Interface Sci ; 677(Pt A): 150-157, 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-39089123

RESUMO

The development of core-shelled heterostructures with the unique morphology can improve the electrochemical properties of hybrid supercapacitors (HSC). Here, CuCo2S4 nanowire arrays (NWAs) are vertically grown on nickel foam (NF) utilizing hydrothermal synthesis. Then, CoMo-LDH nanosheets are uniformly deposited on the CuCo2S4 NWAs by electrodeposition to obtain the CoMo-LDH@CuCo2S4 NWAs/NF electrode. Due to the superior conductivity of CuCo2S4 (core) and good redox activity of CoMo-LDH (shell), the electrode shows excellent electrochemical properties. The electrode's specific capacity is 1271.4 C g-1 at 1 A g-1, and after 10, 000 cycles, its capacity retention ratio is 92.2 % at 10 A g-1. At a power density of 983.9 W kg-1, the CoMo-LDH@CuCo2S4 NWAs/NF//AC/NF device has an energy density of 52.2 Wh kg-1. This indicates that CoMo-LDH@CuCo2S4/NF has a great potential for supercapacitors.

2.
Water Res ; 260: 121962, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38941867

RESUMO

Dissolved black carbon (DBC) released from biochar, is an essential group in the dissolved organic matter (DOM) pool and is widely distributed in aquatic environments. In various advanced oxidation processes (AOPs), DBC exhibits enhanced free radical scavenging compared to typical DOM, attributed to its smaller molecular weight and more compacted aromatic structure; however, the molecular-level transformations of DBC in different AOPs, such as UV/H2O2, UV/PDS, and UV/Chlorine, remain unclear. This study employed a DBC derived from wheat biochar for experimentation. Characterization involved ultraviolet-visible (UV-Vis) spectroscopy and fluorescence excitation-emission-matrix (EEM) spectroscopy, revealing the transformation of DBC through diminished SUVA254 values and reduced intensity of three-dimensional fluorescence peaks. Further insights into the transformation were gained through Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). After each UV-AOP treatment, a conspicuous augmentation in the oxygen content of DBC was observed. The detailed oxygenation processes were elucidated through mass difference analysis, based on 23 types of typical reactions. Results indicated that oxygenation reactions were most frequently detected in all three UV-AOP treatments. Specifically, the hydroxylation (+O) predominated in UV/H2O2, while the di-hydroxylation (+2O) prevailed in UV/PDS. UV/Chlorine treatments commonly exhibited tri-hydroxylation (+3O), with the identification of 1194 Cl-BPs of unknown structures. This study contributes to a comprehensive understanding of the molecular transformations of DBC induced by various free radicals in different UV-AOP processes, leading to a better understanding of the different fates of DBC in UV-AOP processes. In addition, the identification of DBC as a precursor of by-products will also contribute to the understanding of how to inhibit the generation of by-products.


Assuntos
Oxirredução , Raios Ultravioleta , Carbono/química , Peróxido de Hidrogênio/química , Fuligem/química , Carvão Vegetal/química
3.
Mycology ; 15(2): 162-179, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38813473

RESUMO

The genus Agrocybe, situated within the Strophariaceae family, class Agaricomycetes, and phylum Basidiomycota, encompasses a myriad of species exhibiting significant biological activities. This review presents an integrative overview of the secondary metabolites derived from Agrocybe species, elucidating their respective biological activities and potential pharmacological applications. The metabolites under scrutiny encompass a diverse array of biological macromolecules, specifically polysaccharides and lectins, as well as a diverse group of 80 documented small molecular chemical constituents, classified into sterols, sesquiterpenes, volatile compounds, polyenes, and other compounds, their manifesting anti-inflammatory, anticancer, antioxidant, hepatoprotective, antimicrobial, and antidiabetic activities, these metabolites, in which polysaccharides exhibit abundant activities, underscore the potential of the Agrocybe genus as a valuable source of biologically active natural products. The present review emphasises the need for escalated research into Agrocybe, including investigations into the biosynthetic pathways of these metabolites, which could foster the development of novel pharmaceutical therapies to address various health challenges.

4.
Front Plant Sci ; 15: 1404447, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38799090

RESUMO

Rhodiola L. is a genus exhibiting rapid radiation and represents a typical case for studying plastid gene adaptation in species that spread from high altitudes to low altitudes. In this study, 23 samples of 18 Rhodiola species were collected from the Qinghai-Tibetan Plateau and five scattered alpine areas, and the plastid genomes (plastomes) of these species were sequenced, annotated, and compared between high-altitude and widely distributed groups. The plastomes of Rhodiola were found to be highly conserved in terms of gene size, content, and order but highly variable in several lineage-specific features, such as codon usage bias, IR boundary shifting, and distinct repeat sequence structures binding to SSRs. Codon usage in the genes of photosystem II exhibited an obvious preference, reflecting significant environmental adaptation pressures. In this study, three repeat regions compounded with trinucleotide and mononucleotide repeats were found for the first time in R. forrestii, R. himalensis, and R. yunnanensis. High-variability regions such as ndhF, ycf1, trnH-psbA, and rpoC1-rpoB were screened, laying the foundation for the precise identification of these species. The phylogenetic analysis revealed the occurrence of cyto-nuclear discordance, likely originating from the frequent interspecific hybridization events observed within Rhodiola species during rapid radiation. Dioecious and hermaphrodite species can be broadly categorized into two subclades, probably they have different environmental adaptation strategies in response to climate change. In addition, the phylogenetic tree supported the monophyly of R. forrestii and R. yunnanensis, which compose R. Sect. Pseudorhodiola. In conclusion, plastome data enrich the genetic information available for the Rhodiola genus and may provide insight into species migration events during climate change.

5.
Biomol Biomed ; 24(4): 897-911, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38400838

RESUMO

Understanding the intricate relationship between prognosis, immune function, and molecular markers in bladder cancer (BC) demands sophisticated analytical methods. To identify novel biomarkers for predicting prognosis and immune function in BC patients, we combined weighted gene co-expression network analysis (WGCNA) and least absolute shrinkage and selection operator (LASSO) regression analysis. This was conducted using data from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. Ultimately, we screened the junctional adhesion molecule 3 (JAM3) as an independent risk factor in BC. High levels of JAM3 were linked to adverse clinical parameters, such as higher T and N stages. Additionally, a JAM3-based nomogram model accurately predicted 1-, 3- and 5-year survival rates of BC patients, indicating potential clinical utility. Functional enrichment analysis revealed that high JAM3 expression activated the calcium signaling pathway, the extracellular matrix (ECM)-receptor interaction, and the PI3K-Akt signaling pathway, and was positively correlated with genes associated with epithelial-mesenchymal transition (EMT). Subsequently, we found that overexpression of JAM3 promoted the migration and invasion abilities in BC cells, regulating the expression levels of N-cadherin, matrix metallopeptidase 2 (MMP2), and Claudin-1 thereby promoting EMT levels. Additionally, we showed that JAM3 was negatively correlated with anti-tumor immune cells such as CD8+ T cells, while positively correlated with pro-tumor immune cells such as M2 macrophages, suggesting its involvement in immune cell infiltration. The immune checkpoint CD200 also showed a positive correlation with JAM3. Our findings revealed that elevated JAM3 levels are predictive of poor prognosis and immune cell infiltration in BC patients by regulating the EMT process.


Assuntos
Biomarcadores Tumorais , Moléculas de Adesão Celular , Transição Epitelial-Mesenquimal , Neoplasias da Bexiga Urinária , Humanos , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/imunologia , Neoplasias da Bexiga Urinária/mortalidade , Transição Epitelial-Mesenquimal/genética , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Moléculas de Adesão Celular/genética , Moléculas de Adesão Celular/metabolismo , Prognóstico , Masculino , Regulação Neoplásica da Expressão Gênica , Feminino , Linhagem Celular Tumoral , Pessoa de Meia-Idade , Movimento Celular/genética
6.
Environ Res ; 247: 118301, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38272291

RESUMO

Limited utilization of photogenerated charge carriers in titanium dioxide under visible light have hinder its application development. To address this challenge, a novel N-doped carbon quantum dots (N-CQDs) and oxygen vacancies (OVs) synergistically decorated on TiO2 (P25) was synthesized through a facile one-step hydrothermal method. Under visible light irradiation, the first order reaction rate constants of formaldehyde (HCHO) photocatalytic oxidation by OVs-TiO2 and N-CQDs/OVs-TiO2 was significantly higher than that of pristine P25, with 10.1 and 16.7 folds increase, respectively. Characterization results confirmed the generation of OVs on the surface of N-CQDs/TiO2 composite. The optical and electrochemical experiments suggested the electron capture center effect of OVs and the properties of N-CQDs in unique up-converted photoluminescence, efficient charge separation, as well as significant adsorption in visible light region. In addition, the work function also clarified that photoelectrons could transfer from N-CQDs to OVs-TiO2. Furthermore, different relative humidity and electron paramagnetic resonance (EPR) experiments demonstrated that the hydroxyl radical (•OH) was the dominant reactive radical in HCHO photodegradation. The •O2- could also enhance the photodegradation efficiency of HCHO. This work provides an in-depth understanding on the complementary roles of N-CQDs and OVs and is helpful for designing metallic oxide photocatalysts for volatile organic compounds removal.


Assuntos
Carbono , Pontos Quânticos , Carbono/química , Gases , Oxigênio , Pontos Quânticos/química , Luz , Formaldeído , Catálise
7.
Inorg Chem ; 63(1): 730-738, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38100509

RESUMO

A novel copper nanoparticle variant, denoted as Cu98Ni2 NPs, which incorporate Ni atoms in an atomically dispersed manner, has been successfully synthesized via a straightforward one-pot electrochemical codeposition process. These nanoparticles were subsequently employed as an anode to facilitate the oxidation of furfural, leading to the production of hydrogen gas. Voltammetric measurements revealed that the inclusion of trace amounts of Ni atoms in the nanoparticles resulted in a pronounced synergistic electronic effect between Cu and Ni. Consequently, a 43% increase in current density at 0.1 V was observed in comparison to pure Cu NPs. Importantly, when the Cu98Ni2 NPs were irradiated with visible light, a remarkable current density enhancement factor of 505% at 0.1 V was achieved relative to that of pure Cu NPs in the absence of light. This enhancement can be attributed to localized surface plasmon resonance induced by visible light, which triggers photothermal and photoelectric effects. These effects collectively contribute to the significant overall improvement in the electrocatalytic oxidation of furfural, leading to enhanced hydrogen evolution.

8.
Front Oncol ; 13: 1210314, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37664018

RESUMO

Objective: To explore the clinicopathological features of patients with ultra-low expression of human epidermal growth factor 2 (HER-2) in breast cancer and its impact on prognosis. Methods: Data from 1024 patients with primary breast cancer having HER-2 ultra-low expression from January 01, 2018, to December 31, 2018, were collected and analyzed retrospectively. The clinicopathological features and prognosis were compared using a chi-squared test or Fisher exact probability method. COX regression analysis and log-rank test were used to explore the factors related to the postoperative 5-year survival rate. All analytical data were defined as statistically significant (P < 0.05). Results: Overall survival (OS) was higher in the HER-2 ultra-low group compared to the low expression group (P = 0.022). The tumor diameter, lymph node metastasis (LNM), and Ki67 expression were factors affecting DFS in the HER-2 ultra-low expression group (P < 0.05). The tumor diameter and LNM were risk factors affecting the OS (P < 0.05) in the HER-2 ultra-low expression group. LNM and Ki67 expression were risk factors affecting DFS (P < 0.05) in the HER-2 low expression group. LNM was considered an independent risk factor affecting OS (P < 0.05). Conclusion: Breast cancer with HER-2 ultra-low expression has differences in the clinicopathological features. Breast cancer with HER-2 low expression is more aggressive and has a worse prognosis. This study provides a reference to consider in the treatment of HER-2-low and -ultra-low expression breast cancer.

9.
Environ Sci Technol ; 57(47): 18811-18824, 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-37428486

RESUMO

During the ozonation of wastewater, hydroxyl radicals (•OH) induced by the reactions of ozone (O3) with effluent organic matters (EfOMs) play an essential role in degrading ozone-refractory micropollutants. The •OH yield provides the absolute •OH formation during ozonation. However, the conventional "tert-Butanol (t-BuOH) assay" cannot accurately determine the •OH yield since the propagation reactions are inhibited, and there have been few studies on •OH production induced by EfOM fractions during ozonation. Alternatively, a "competitive method", which added trace amounts of the •OH probe compound to compete with the water matrix and took initiation reactions and propagation reactions into account, was used to determine the actual •OH yields (Φ) compared with that obtained by the "t-BuOH assay" (φ). The Φ were significantly higher than φ, indicating that the propagation reactions played important roles in •OH formation. The chain propagation reactions facilitation of EfOMs and fractions can be expressed by the chain length (n). The study found significant differences in Φ for EfOMs and fractions, precisely because they have different n. The actual •OH yield can be calculated by n and φ as Φ = φ (1 + n)/(nφ + 1), which can be used to accurately predict the removal of micropollutants during ozonation of wastewater.


Assuntos
Ozônio , Poluentes Químicos da Água , Purificação da Água , Águas Residuárias , Poluentes Químicos da Água/análise , Água , Radical Hidroxila , terc-Butil Álcool
10.
Curr Microbiol ; 80(7): 235, 2023 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-37278966

RESUMO

Trichoderma is a genus of common filamentous fungi that display a various range of lifestyles and interactions with other fungi. The interaction of Trichoderma with Morchella sextelata was explored in this study. Trichoderma sp. T-002 was isolated from a wild fruiting body of Morchella sextelata M-001 and identified as a closely related species of Trichoderma songyi based on morphological chracteristics and phylogenetic analysis of translation elongation factor1-alpha and inter transcribed spacer of rDNA. Further, we focussed on the influence of dry mycelia of T-002 on the growth and synthesis of extracellular enzymes of M-001. Among different treatments, M-001 showed the highest growth of mycelia with an optimal supplement of 0.33 g/100 mL of T-002. Activities of extracellular enzymes of M-001 were enhanced significantly by the optimal supplement treatment. Overall, T-002, a unique Trichoderma species, had a positive effect on mycelial growth and synthesis of extracellular enzymes of M-001.


Assuntos
Ascomicetos , Trichoderma , Trichoderma/genética , Filogenia , Ascomicetos/genética , DNA Ribossômico
11.
Environ Sci Pollut Res Int ; 30(9): 23035-23046, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36319923

RESUMO

In recent years, the combination of iron carbon micro-electrolysis (ICME) with constructed wetlands (CWs) for removal of nitrogen and phosphorus has attracted more and more attention. However, the removal mechanisms by CWs with iron carbon (Fe-C) substrates are still unclear. In this study, the Fe-C based CW (CW-A) was established to improve the removal efficiencies of nitrogen and phosphorus by optimizing the operating conditions. And the removal mechanisms of nitrogen and phosphorus were explored. The results shown that the removal rates of COD, NH4+-N, NO3--N, TN, and TP in CW-A could reach up to 84.4%, 94.0%, 81.1%, 86.6%, and 84.3%, respectively. Wetland plants and intermittent aeration have dominant effects on the removal of NH4+-N, while the removal efficiencies of NO3--N, TN, and TP were mainly affected by Fe-C substrates, wetland plants, and HRT. XPS analysis revealed that Fe(0)/Fe2+ and their valence transformation played important roles on the pollutants removal. High-throughput sequencing results showed that Fe-C substrates and wetland plants had considerable impacts on the microbial community structures, such as richness and diversity of microorganism. The relative abundance of autotrophic denitrification bacteria (e.g., Denitatsoma, Thauera, and Sulfuritalea) increased in CW-A than CW-C. The electrons and H2/[H] produced from Fe-C substrates were utilized by autotrophic denitrification bacteria for NO3--N reduction. Microbial degradation was the main removal mechanism of nitrogen in CW-A. Removal efficiency of phosphorus was enhanced resulted from the reaction of phosphate with iron ion. The application of CWs with Fe-C substrates and plants presented great potential for simultaneous removal of nitrogen and phosphorus.


Assuntos
Carbono , Eliminação de Resíduos Líquidos , Eliminação de Resíduos Líquidos/métodos , Áreas Alagadas , Fósforo , Nitrogênio/química , Ferro , Desnitrificação
12.
Sci Total Environ ; 842: 156692, 2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-35752235

RESUMO

Nitrogenous disinfection by-products (N-DBPs) raise increasing concerns because of their high genotoxicity, cytotoxicity, and carcinogenicity compared to carbonaceous disinfection by-products (C-DBPs). Nitrogen-containing disinfectants, dissolved organic nitrogen (DON), and inorganic nitrogen may all promote the formation of N-DBPs. Therefore, it is urgent to explore the dominant nitrogen source of N-DBPs under the coexistence of multiple nitrogen sources. In this study, the effects of amino acids, nitrate, ammonia, and chloramine as different types of nitrogen sources on the formation of five N-DBPs were investigated systematically, including chloroacetonitrile (CAN), dichloroacetonitrile (DCAN), bromochloroacetonitrile (BCAN), dibromoacetonitrile (DBAN) and dichloroacetamide (DCAcAm). L-Aspartic acid (L-Asp) as the organic nitrogen source showed a high potential on the formation of N-DBPs by forming acetonitrile intermediates. Ammonia as the inorganic nitrogen source consumed oxidants and changed the existing form of chloramine, thus inhibiting the formation of N-DBPs. Instead of providing nitrogen to N-DBPs, nitrate as a salt promoted the volatilization of N-DBPs, thereby reducing the detected N-DBPs. Furthermore, an isotope labeling method was applied to clearly trace the nitrogen sources of N-DBPs via GC-MS with electron ionization. 15N-chloramine, 15N-amino acid, 15N-nitrate and 15N-ammonia were selected as the corresponding isotopic nitrogen sources. The results indicated that chloramine was the major nitrogen contributor to five N-DBPs during the chloramination of L-Asp under the coexistence of multiple nitrogen sources, ranging from 61 % to 79 %. The influence of environmental factors (reaction time, pH, and bromide) on the formation of N-DBPs during chloramination was also investigated. There was competition between brominated N-DBPs and chlorinated N-DBPs in chloramination. With the increase of reaction time or bromine, the formation potentials of chlorinated N-DBPs gradually decreased, while brominated N-DBPs gradually increased. Moreover, higher pH inhibited the generation of N-DBPs.


Assuntos
Desinfetantes , Poluentes Químicos da Água , Purificação da Água , Amônia , Cloraminas/química , Desinfetantes/química , Desinfecção/métodos , Halogenação , Marcação por Isótopo , Nitratos , Nitrogênio/química , Compostos Orgânicos , Água , Poluentes Químicos da Água/análise , Purificação da Água/métodos
13.
Sci Total Environ ; 828: 153984, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35202700

RESUMO

As an important component of dissolved organic matter (DOM), dissolved black carbon (DBC) which is characterized of abundant aromatic and oxygen-containing functional groups, is widely distributed in aquatic environments. Its presence may hinder the oxidation of organic micro-pollutants during advanced oxidation processes (AOPs) via free radicals scavenging effect. However, the second-order reaction rate constants of DBC with different free radicals including hydroxyl radical (OH•), sulfate radical (SO4•-), reactive chlorine radicals (RCR) are unknown and the relationship between the chemical composition of DBC and the second-order reaction rate constants during different AOPs (UV/H2O2, UV/PDS, UV/Chlorine) is also unclear. In this study, a plant-derived DBC was extracted from wheat biochar and fractionated according to molecular weight (i.e., <10 k, <3 k, and < 1 k Da). The second order rate constants of DBC reaction with different free radicals were determined by competitive kinetic method. Besides, the chemical composition of DBC was revealed by ultraviolet-visible (UV-Vis) spectroscopy, fluorescence excitation-emission-matrix (EEM) spectroscopy Fourier Transform Infrared (FTIR), X-ray photoelectron spectroscopy (XPS), and Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) combined with statistical analysis. The results showed that the second-order rate constants decreased as the molecular weight increased. For the <1 k Da DBC, the kDBC-OH•, kDBC-SO4•--, kDBC-RCR were (1.83 ± 0.06) × 104, (7.60 ± 0.21) × 103, and (1.71 ± 0.13) × 104 L·mgC-1·s-1, which were 1.98, 2.19, 1.43 times of that for the <10 k Da fraction and 1.38, 1.36, 1.24 times of that for the <3 k Da fraction in UV/H2O2, UV/PDS and UV/Chlorine processes. In addition, the results of chemical composition analysis showed that DBC mainly contained humic substances and was rich in O-containing functional groups such as CO. The second order reaction rate constants of DBC with different free radicals decreased with increasing the molecular weight of DBC due to the more aggregated structure of the small molecules that the inner carbon of DBC was not easily exposed to free radicals.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Cloro/análise , Cromatografia Gasosa-Espectrometria de Massas , Peróxido de Hidrogênio/química , Radical Hidroxila/química , Cinética , Oxirredução , Fuligem/análise , Sulfatos , Raios Ultravioleta , Poluentes Químicos da Água/análise , Purificação da Água/métodos
14.
Chemosphere ; 291(Pt 1): 133007, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34826443

RESUMO

Photocatalysis is an effective method for the removal of formaldehyde (HCHO), and high-efficiency visible-light-driven photocatalysts were urgently required. Herein, oxygen vacancies (OVs) and nano copper oxides (CuOx) synergistically modified TiO2 (CuOx/TiO2-x) photocatalysts were synthesized by one-step hydrothermal followed by impregnation method. The photocatalytic decomposition of HCHO reached 100% at initial concentration of 180 ppm under relative humidity (RH) = 60% by 0.1g CuOx/TiO2-x in 150 min visible light irradiation. Characterization results explored the complementary effect of OVs and CuOx systematically. The OVs increased the separation efficiency of photogenerated charge carriers and act as adsorption/active sites in HCHO photocatalytic oxidation. The moisture and O2 were adsorbed and actived by OVs to generate reactive oxygen species (ROS). After doped CuOx on the surface of TiO2-x, the photoexcited electrons in Cu2O could transfer to the conduction band (CB) of TiO2-x and the photoexcited electrons of TiO2-x could be captured by Cu nanoparticles. Therefore, more ROS were generated due to the synergistic effect of OVs and CuOx. The In-situ Fourier transform infrared (in-situ FTIR) measurements show the hydroxyl radical (•OH) was the dominant radical in HCHO photocatalytic oxidation, while •O2- could also upgrade the photodegradation efficiency of HCHO. Furthermore, the stability tests showed the degradation efficiency of HCHO still reached 90% after five recycles, indicating that CuOx/TiO2-x nanocomposites displayed a stable and high photoactivity in volatile organic compounds (VOCs) decomposition.


Assuntos
Gases , Oxigênio , Catálise , Cobre , Formaldeído , Luz , Óxidos , Titânio
15.
Environ Res ; 179(Pt B): 108855, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31678723

RESUMO

Dissolved black carbon (DBC), widely distributed in the aquatic environments, can accelerate sunlight-driven photo-transformation of micropollutants, however the photosensitization mechanisms are not clear. Herein, the DBC was extracted from bamboo biochar and fractionated by molecular weight (i.e. <10 k, <3 k, and <1 k Da). The effects of DBC on chlortetracycline (CTC) photolysis behaviors, and the role of chemical composition (i.e., molecular weight and chemical structure) in DBC-mediated photo-transformation were investigated. The results showed that DBC could accelerate CTC photodegradation significantly. At low DBC concentrations (<6.0 mg C/L), the photodegradation rate constant of CTC increased from 0.0299 to 0.0416 min-1 with the increasing DBC concentration. Via quenching experiment, the triplet excited-state of DBC was identified as the dominant reactive intermediate with >90% contribution to total CTC photodegradation. In addition, it was found that the photosensitive efficiency of DBC increased as the molecular weight decreased, and the stronger photosensitization ability exhibited in DBC with low-molecular weight was potentially attributed to its higher content of carbonyl compounds. The observed photosensitive efficiency of DBC sharply decreased after reduction by NaBH4, further confirming the key role of carbonyl compounds in the photosensitization process. Moreover, based on the result of photoproducts, the amidogen in CTC was verified to be susceptible to react with 3DBC*.


Assuntos
Carvão Vegetal/química , Clortetraciclina/química , Sasa , Poluentes Químicos da Água/química , Clortetraciclina/análise , Processos Fotoquímicos , Fotólise , Fuligem , Poluentes Químicos da Água/análise
16.
Appl Immunohistochem Mol Morphol ; 26(5): 337-344, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-27556820

RESUMO

Glioblastoma multiforme (GBM) has a high recurrence and mortality rate. Because of a poor understanding of the mechanism for this disease, treatment regimens have remained limited. Vimentin, one of the major cytoskeletal proteins, is associated with cellular structure. However, the function of vimentin in GBM is still undefined. In the present study, we investigated the expression level of vimentin in 179 GBM tissues using immunohistochemistry. We found that the vimentin expression level was associated with the time to progression (P=0.029). A Kaplan-Meier analysis revealed that patients with high vimentin expression had a significantly shorter overall survival (P=0.0002) and progression-free survival (P=0.0001) compared with those with low expression. Furthermore, in vitro experiments showed that withaferin-A, a chemical inhibitor of vimentin, could inhibit GBM cell migration and invasion activity when its concentrations were <0.5 µM, and higher concentrations of withaferin-A could decrease the viability of U251and U87 cells significantly. In conclusion, our results indicated that vimentin may play an important role in the progression of GBM.


Assuntos
Neoplasias Encefálicas/diagnóstico , Glioblastoma/diagnóstico , Vimentina/metabolismo , Adulto , Idoso , Neoplasias Encefálicas/mortalidade , Carcinogênese , Linhagem Celular Tumoral , Movimento Celular , Citoesqueleto/metabolismo , Feminino , Glioblastoma/mortalidade , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Recidiva Local de Neoplasia , Análise de Sobrevida , Vimentina/antagonistas & inibidores , Vitanolídeos/farmacologia
17.
Oncotarget ; 8(19): 31119-31132, 2017 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-28415709

RESUMO

Glioblastoma (GBM) is associated with poor prognosis due to its resistance to surgery, irradiation, and conventional chemotherapy. Thus, efficient therapeutic approaches for the treatment of GBM are urgently needed. HSP70 is an antiapoptotic protein that participates in the inhibition of both mitochondrial and membrane receptor apoptosis pathways and is highly expressed in glioma tissues. Here, we investigated a derivative of apoptin; specifically, a chicken anemia viral protein with selective toxicity toward cancer cells that can inhibit hyperactive molecules, including HSP70. Our earlier studies demonstrated that apoptin directly binds to the promoter of HSP70 and inhibits HSP70 transcription, which contributes to HSP70 downregulation. This study provides the first demonstration of the therapeutic potential of an apoptin-derived peptide for the treatment of GBM by identifying the minimal region of the apoptin domain required for interaction with the heat-shock element (HSE). This apoptin-derived peptide (ADP) inhibits glioma cell proliferation and tumor growth as well as exhibits an increased ability to promote apoptosis in GBM cells compared with rapamycin and temozolomide. ADP treatment inhibited xenograft tumor growth and increased the overall health and survival of nude mice implanted with GBM cells. These effects were measured in tumors obtained from cell lines and were observed in both intracranial and subcutaneous xenografts. In conclusion, we provide the first demonstration that ADP has therapeutic potential for the treatment of human GBM. Specifically, this study suggests that ADP is a potent candidate for drug development based on its favorable toxicity and pharmacokinetic profiles as well as its time- and cost-saving benefits.


Assuntos
Antineoplásicos/farmacologia , Proteínas do Capsídeo/química , Peptídeos/farmacologia , Difosfato de Adenosina/metabolismo , Animais , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Expressão Gênica , Glioma/tratamento farmacológico , Glioma/genética , Glioma/metabolismo , Glioma/patologia , Proteínas de Choque Térmico HSP70/antagonistas & inibidores , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/metabolismo , Humanos , Camundongos , Modelos Moleculares , Peptídeos/química , Conformação Proteica , Ensaios Antitumorais Modelo de Xenoenxerto
18.
Anticancer Drugs ; 28(4): 401-409, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28045701

RESUMO

Apoptin, derived from the chicken anemia virus, has been found to exert tumor-preferential apoptotic activity. It is a potential anticancer agent with direct clinical applications. However, if this viral protein were to be used as a new drug, it might also induce a strong immune response, causing toxic side effects. In a previous study, our group showed that TAT-apoptin downregulates the stress expression of heat shock protein 70 by competing with heat shock factor protein 1 in binding to the heat shock element (HSE) of the promoter region of heat shock protein 70, thus inducing specific apoptosis in HepG2 cells. In this study, we investigated the HSE-binding properties of the minimal functional region of apoptin. We showed that apoptin's nuclear localization signals 1 and nuclear localization signals 2 represented functional regions that could bind with HSE and that this binding capacity was increased by polymers formed through the introduction of a leucine-rich stretch. Our data also showed that truncated combinatorial apoptin peptide has greater tumor-specific cell-killing activity and could be a potential antitumor agent.


Assuntos
Proteínas do Capsídeo/metabolismo , Proteínas do Capsídeo/farmacologia , Proteínas de Choque Térmico HSP70/genética , Fatores de Transcrição de Choque Térmico/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/genética , Animais , Ligação Competitiva , DNA de Neoplasias/genética , DNA de Neoplasias/metabolismo , Relação Dose-Resposta a Droga , Regulação para Baixo/efeitos dos fármacos , Feminino , Proteínas de Choque Térmico HSP70/biossíntese , Proteínas de Choque Térmico HSP70/metabolismo , Fatores de Transcrição de Choque Térmico/genética , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Neoplasias/metabolismo , Neoplasias/patologia , Fragmentos de Peptídeos/metabolismo , Fragmentos de Peptídeos/farmacologia , Regiões Promotoras Genéticas , Domínios Proteicos , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Adv Sci (Weinh) ; 3(5): 1500363, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27812467

RESUMO

Spherical materials with yolk-shell structure have great potential for a wide range of applications. The main advantage of the yolk-shell geometry is the possibility of introducing different chemical or physical properties within a single particle. Here, a one-step hydrothermal synthesis route for fabricating amphoteric yolk-shell structured aluminum phenylphosphonate microspheres using urea as the precipitant is proposed. The resulting microspheres display 3D sphere-in-sphere architecture with anionic core and cationic shell. The controllable synthesis of aluminum phosphates with various morphologies is also demonstrated. The anionic core and cationic shell of the aluminum phenylphosphonate microspheres provide docking sites for selective adsorption of both cationic methylene blue and anionic binuclear cobalt phthalocyanine ammonium sulphonate. These new adsorbents can be used for simultaneous capture of both cations and anions from a solution, which make them very attractive for various applications such as environmental remediation of contaminated water.

20.
Waste Manag Res ; 32(6): 519-26, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24951551

RESUMO

This study explored the amount and composition of pyrolysis gas and oil derived from wet material or dried material during the preparation of sludge-corncob activated carbon, and evaluated the physicochemical and surface properties of the obtained two types of sludge-corncob-activated carbons. For wet material, owing to the presence of water, the yields of sludge-corncob activated carbon and the oil fraction slightly decreased while the yield of gases increased. The main pyrolysis gas compounds were H2 and CO2, and more H2 was released from wet material than dried material, whereas the opposite holds for CO2 Heterocyclics, nitriles, organic acids, and steroids were the major components of pyrolysis oil. Furthermore, the presence of water in wet material reduced the yield of polycyclic aromatic hydrocarbons from 6.76% to 5.43%. The yield of furfural, one of heterocyclics, increased sharply from 3.51% to 21.4%, which could be explained by the enhanced hydrolysis of corncob. In addition, the surface or chemical properties of the two sludge-corncob activated carbons were almost not affected by the moisture content of the raw material, although their mesopore volume and diameter were different. In addition, the adsorption capacities of the two sludge-corncob activated carbons towards Pb and nitrobenzene were nearly identical.


Assuntos
Carvão Vegetal/química , Óleos/química , Esgotos/química , Gerenciamento de Resíduos/métodos , Dióxido de Carbono , Cromatografia Gasosa , Furaldeído/química , Cromatografia Gasosa-Espectrometria de Massas , Hidrogênio , Hidrólise , Hidrocarbonetos Policíclicos Aromáticos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Gerenciamento de Resíduos/instrumentação , Água/química , Zea mays
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