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1.
Langmuir ; 40(40): 20986-20994, 2024 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-39321402

RESUMO

Ionic conductive cellulose hydrogels are some of the most promising candidates for flexible sensors. However, it is difficult to simultaneously prepare cellulose hydrogels with high mechanical strength, good ionic conductivity, and antifreeze performance. In this work, a natural clay (attapulgite)-reinforced cellulose hydrogel was fabricated. Through a one-pot method, cellulose and attapulgite were dispersed in a concentrated ZnCl2 solution. The obtained hydrogel exhibited a dual network of hydrogen bonds and Zn2+-induced ionic interactions. Attapulgite serves as an inorganic filler that can regulate the hydrogen-bonding density among cellulose molecules and provides abundant channels for fast ion transport. By optimizing the attapulgite loading, a mechanically strong (compressive strength up to 1.10 MPa), tough (fracture energy up to 0.36 MJ m-3), highly ionic conductive (4.15 S m-1), and freezing-tolerant hydrogel was prepared. These hydrogels can be used for sensitive and stable human motion sensing, demonstrating their great potential for healthcare applications.

2.
Langmuir ; 40(10): 5288-5296, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38417256

RESUMO

A kind of ionic conductive gel (also named eutectogel) is developed from an inorganic salt (ZnCl2)-based deep eutectic solvent (DES). The ternary DES consists of ZnCl2, acrylic acid, and water, and cotton linter cellulose is introduced into the DES system to tailor its mechanical and conductive properties. Enabled by the extensive hydrogen bonds and ion-dipole interactions, the obtained eutectogel displays superior ionic conductivity (0.33 S/m), high stretchability (up to 2050%), large tensile strength (1.82 MPa), and wide temperature tolerance (-40 to 60 °C). In particular, the water-induced coordination interactions can tune the strength of hydrogen/ionic bonds in the eutectogels, imparting them with appealing humidity sensing ability in complex and extreme conditions.

3.
Ecotoxicol Environ Saf ; 265: 115494, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37742577

RESUMO

A systematic study of the movement of PAHs (Polycyclic aromatic hydrocarbons) and their derivatives through air, soil, and water is key to understanding the exchange and transport mechanisms of these pollutants in the environment and for ultimately improving environmental quality. PAHs and their derivatives, such as nitrated PAHs (NPAHs), oxygenated PAHs (OPAHs), brominated PAHs (BrPAHs) and chlorinated PAHs (ClPAHs), were analyzed in air, bulk deposition, soil, and water samples collected from urban, rural, field, and background sites on the eastern coast of China. The goal was to investigate and discuss their spatiotemporal variations, exchange fluxes, and transport potential. The concentrations of PAHs and their derivatives in the air and bulk deposition displayed distinct seasonal patterns, with higher concentrations observed during the winter and spring and lower concentrations during the summer and autumn. NPAHs exhibited the opposite trend. Significant urban-rural gradients were observed for most of the PAHs and their derivatives. According to the air-soil fugacity calculations, 2-3 ring PAHs, BrPAHs, and ClPAHs were found to volatilize from the soil into the air, while 4-7 ring PAHs, OPAHs, and NPAHs deposited from the air into the soil. The air-water fugacity of the PAHs and their derivatives indicated that surface water was an important source for the ambient atmosphere in Qingdao. The characteristic travel distances (CTDs) and persistence (Pov) for atmospheric transport were much lower than that for the water samples, which may be due to the longer half-lives of PAHs and their derivatives in water. NPAHs and ClPAHs with long transport distances and strong persistence in water could lead to a significant impact on marine pollution.

4.
Phytother Res ; 37(9): 4076-4091, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37156642

RESUMO

Molecular-targeted therapy has shown its effectiveness in pancreatic cancer, while single-targeted drug often cannot provide long-term benefit because of drug resistance. Fortunately, multitarget combination therapy can reverse drug resistance and achieve better efficacy. The typical treatment characteristics of traditional Chinese medicine monomer on tumor are multiple targets, with small side effects, low toxicity, and so forth. Agrimoniin has been reported to be effective on some cancers, while the mechanism still needs to be clarified. In this study, we used 5-ethynyl-2'-deoxyuridine, cell counting kit-8, flow cytometry, and western blot experiments to confirm that agrimoniin can significantly inhibit the proliferation of pancreatic cancer cell PANC-1 by inducing apoptosis and cell cycle arrest. In addition, by using SC79, LY294002 (the agonist or inhibitor of AKT pathway), and U0126 (the inhibitor of ERK pathway), we found that agrimoniin inhibited cell proliferation by simultaneously inhibiting AKT and ERK pathways. Moreover, agrimoniin could significantly increase the inhibitory effect of LY294002 and U0126 on pancreatic cancer cells. Meanwhile, in vivo experiments also supported the above results. In general, agrimoniin is a double-target inhibitor of AKT and ERK pathways in pancreatic cancer cells; it is expected to be used as a resistance reversal agent of targeted drugs or a synergistic drug of the inhibitor of AKT pathway or ERK pathway.


Assuntos
Sistema de Sinalização das MAP Quinases , Neoplasias Pancreáticas , Humanos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proliferação de Células , Neoplasias Pancreáticas/tratamento farmacológico , Linhagem Celular Tumoral , Apoptose
5.
Transfus Apher Sci ; 60(2): 103034, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33341364

RESUMO

BACKGROUND AND OBJECTIVES: The storage lesion of the red blood cell affects the life span of RBC and the quality of blood component. The elucidation of this mechanism is helpful to reduce the storage damage of RBC and improve the efficacy and safety of blood transfusion. The aim of this study was to discover the potential molecular mechanism of erythrocyte storage lesion with Under-collected whole blood (UC-WB) model. METHODS: The label-free MS/MS quantitative method was used to identify the differential proteins of erythrocyte membrane proteins and the difference of Rab11B, V-ATPase and plasma GDI2 protein expression were further verified by western blot at the end of blood storage. RESULTS: A total of 12 Rab proteins and 3 interacting effector proteins were identified among the membrane protein of normal WB and UC-WB, including 5 differential Rab proteins and 2 interacting effector proteins. Compared with normal WB, the expression of membrane Rab11B protein and ATP6V1B1/2 subunit of V-ATPases protein as well as the plasma GDI2 protein of UC-WB increased at the end of storage period. CONCLUSION: Rab protein might be related to RBC storage lesions, Rab11B participates in the RBC storage lesion through Rab11B/V-ATPases pathways.


Assuntos
Preservação de Sangue/métodos , Sangue/metabolismo , Proteínas rab de Ligação ao GTP/metabolismo , Voluntários Saudáveis , Humanos
6.
Mikrochim Acta ; 188(1): 14, 2021 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-33389237

RESUMO

A simple and feasible pH meter-based immunoassay is reported for detection of C-reactive protein (CRP) using glucose oxidase (GOD)-conjugated dendrimer loaded with platinum nanozyme. Initially, platinum nanozymes were loaded into the dendrimers through an in situ synthetic method. Then, GOD and monoclonal anti-CRP antibody with a high molar ratio were covalently conjugated onto carboxylated dendrimers via typical carbodiimide coupling. The immunoreaction was carried out with a competitive mode in a CRP-coated microplate. Along with formation of immunocomplex, the added glucose was oxidized into gluconic acid and hydrogen peroxide by GOD, and the latter was further decomposed by platinum nanozyme, thus accelerating chemical reaction in the positive direction. The produced gluconic acid changed the pH of detection solution, which was determined using a handheld pH meter. Under optimum conditions, the pH meter-based immunoassay gave a good signal toward target CRP from 0.01 to 100 ng mL-1. The limit of detection was 5.9 pg mL-1. An intermediate precision ≤ 11.2% was acquired with batch-to-batch identification. No nonspecific adsorption was observed during a series of procedures to detect target CRP, and the cross-reaction against other biomarkers was very low. Importantly, our system gave well-matched results for analysis of human serum samples relative to a referenced ELISA kit.Graphical abstract.


Assuntos
Proteína C-Reativa/análise , Dendrímeros/química , Glucose Oxidase/química , Imunoensaio/métodos , Nanopartículas Metálicas/química , Anticorpos Imobilizados/imunologia , Anticorpos Monoclonais/imunologia , Proteína C-Reativa/imunologia , Catálise , Humanos , Peróxido de Hidrogênio/química , Concentração de Íons de Hidrogênio , Limite de Detecção , Oxirredução , Platina/química , Reprodutibilidade dos Testes
7.
Chemistry ; 26(35): 7918-7922, 2020 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-32274873

RESUMO

Zeolite ZIF-8 has been etched with acid to form microporous ZIF-8-E crystals. These were then introduced into a polyethersulfone (PES) membrane matrix to enhance its CO2 /N2 separation performance. Open through pores of size about 100 nm formed in the ZIF-8 crystals allow the ingrowth of polyethersulfone chains, ensuring a reduction in the number of nonselective voids, thereby achieving better interaction between ZIF-8-E and PES. As a result, the CO2 /N2 separation performance of the ZIF-8-E/PES membrane increased significantly, showing a CO2 permeability of 15.7 Barrer and a CO2 /N2 ideal selectivity of 6.5.

8.
Inorg Chem ; 59(8): 5424-5432, 2020 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-32223144

RESUMO

The development of highly active, stable, and inexpensive molecular water oxidation catalysts (WOCs) is important for eventually realizing artificial photosynthesis. The dinuclear earth-abundant molecular WOCs are of great interest as the latent synergy of two adjacent metals of the molecule could enhance the activity of the catalyst for water oxidation, just as the synergistic catalysis effect of metal ions in many metalloenzymes. Herein we report the dinuclear copper complex [L1Cu2(µ-OH)](BF4)3 (1, L1 = N,N'-dimethyl-N,N'-bis{2-[bis(2-pyridinylmethyl)amino]ethyl}ethane-1,2-diamine) with a flexible linker and its mononuclear counterpart [L2Cu(OH2)](BF4)2(2, L2 = N,N-dimethyl-N',N'-bis(2-pyridylmethyl)ethane-1,2-diamine) as WOCs. X-ray diffraction analysis showed that in the crystal structure of 1 there is an extraneous water molecule located very close to the bridged O atom, resembling the proposed structure of the transition state for the O-O bond formation. Comparative studies on the performances of 1 and 2 for electrochemical water oxidation at pH 12 manifested that 1 displayed a much higher activity and better stability than that of 2. The kcat1 of 144 s-1 for 1 is on a par with those of the state-of-the-art earth-abundant molecular WOCs reported to date under similar test conditions. Experimental studies and DFT calculations suggest that the water oxidation catalyzed by 1 proceeds via a unimolecular two-site mechanism with a much lower energy barrier for the O-O bond formation step compared to that for 2.

9.
Molecules ; 24(21)2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31683670

RESUMO

Asatone and isoasatone A from Asarum ichangense Cheng were determined to be defensive compounds to some insects in a previous investigation. However, the anti-insect activity mechanisms to caterpillar are still unclear. The compounds asatone and isoasatone A from A. ichangense were induced by Spodoptera litura. The anti-insect activity of asatone and isoasatone A to S. litura was further tested by weight growth rate of the insect through a diet experiment. Isoasatone A showed a more significant inhibitory effect on S. litura than asatone on the second day. The concentration of asatone was higher than isoasatone A in the second instar larvae of S. litura after 12 h on the feeding test diet. Both compounds caused mid-gut structural deformation and tissue decay as determined by mid-gut histopathology of S. litura. Furthermore, some detoxification enzyme activity were measured by relative expression levels of genes using a qPCR detecting system. Asatone inhibited the gene expression of the cytochrome P450 monooxygenases (P450s) CYP6AB14. Isoasatone A inhibited the relative expression levels of CYP321B1, CYP321A7, CYP6B47, CYP6AB14, and CYP9A39. Asatone increased the relative gene expression of the glutathione transferases (GSTs) SIGSTe1 and SIGSTo1, in contrast, isoasatone A decreased the relative gene expression of SIGSTe1 by about 33 fold. Neither compound showed an effect on acetylcholinesterase SIAce1 and SIAce2. The mechanism of anti-insect activity by both compounds could be explained by the inhibition of enzymes P450s and GSTs. The results provide new insights into the function of unique secondary metabolites asatone and isoasatone A in genus Asarum, and a new understanding of why A. ichangense is largely free of insect pests.


Assuntos
Sistema Enzimático do Citocromo P-450/metabolismo , Glutationa Transferase/metabolismo , Lignanas/farmacologia , Spodoptera/efeitos dos fármacos , Spodoptera/enzimologia , Acetilcolinesterase/genética , Acetilcolinesterase/metabolismo , Animais , Asarum/química , Sistema Enzimático do Citocromo P-450/genética , Sistema Digestório/efeitos dos fármacos , Sistema Digestório/patologia , Regulação da Expressão Gênica/efeitos dos fármacos , Glutationa Transferase/genética , Lignanas/química , Spodoptera/genética
10.
Angew Chem Int Ed Engl ; 58(22): 7366-7370, 2019 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-30938928

RESUMO

Inspired by the anti-freezing mechanisms found in nature, ionic compounds (ZnCl2 /CaCl2 ) are integrated into cellulose hydrogel networks to enhance the freezing resistance. In this work, cotton cellulose is dissolved by a specially designed ZnCl2 /CaCl2 system, which endows the cellulose hydrogels specific properties such as excellent freeze-tolerance, good ion conductivity, and superior thermal reversibility. Interestingly, the rate of cellulose coagulation could be promoted by the addition of extra water or glycerol. This new type of cellulose-based hydrogel may be suitable for the construction of flexible devices used at temperature as low as -70 °C.

11.
Org Biomol Chem ; 16(23): 4279-4287, 2018 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-29796558

RESUMO

An intriguing conversion of arylglyoxal, cyclic dicarbonyl compounds and phenols to diverse furan analogues under FeCl3 or MeSO3H catalysis is reported. Utilizing this synthetic protocol, a variety of furan analogues could be easily obtained in moderate to good yields with different substituted patterns by varying the reaction medium. Atom-economical characteristics and mild conditions of this method are in accord with the concept of modern green chemistry.

12.
Int J Biol Macromol ; 275(Pt 1): 133507, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38944082

RESUMO

Deep eutectic solvents (DESs) hold great potential in biorefining because they can efficiently deconstruct the recalcitrant structure of lignocellulose. In particular, inorganic salts with Lewis acids have been proven to be effective at cleaving lignin-carbohydrate complexes. Herein, a Zr-based DES system composed of metal chloride hydrate (ZrOCl2·8H2O) and ethylene glycol (EG) was designed and used for poplar powder pretreatment. Zr4+-based salts provide sufficient acidity for lignocellulose depolymerization. The acidity of the DES was analysed by the Kamlet-Taft solvatochromic parameter, and the results demonstrated that the acidity can be regulated by the DES composition. Under the optimum conditions (ZrOCl2·8H2O:EG molar ratio of 1:2), the DES pretreatment removes nearly 100 % hemicellulose and 94.7 % lignin. The recovered lignin exhibited a low polydispersity of 1.7. The cellulose residues deliver an efficiency of 94.4 % upon enzymatic digestion. Moreover, the DES can be easily recovered with high yield and purity, and the recycled DES still maintains high delignification and enzymatic hydrolysis efficiencies. The proposed DES pretreatment technology is promising for biomass valorization.


Assuntos
Solventes Eutéticos Profundos , Etilenoglicol , Lignina , Zircônio , Lignina/química , Etilenoglicol/química , Zircônio/química , Solventes Eutéticos Profundos/química , Hidrólise , Cloretos/química , Biomassa , Solventes/química , Populus/química
13.
Carbohydr Polym ; 327: 121695, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38171664

RESUMO

Interfacial evaporation through hydrogel-based evaporators is emerging as a sustainable and cost-effective strategy for drinkable water production. Herein, a specially designed bi-layer hydrogel evaporator was fabricated and used for efficient solar water desalination. With cotton linter as cellulose precursor, it was dispersed in a highly concentrated ZnCl2 (65 %) solution, and cross-linked by epichlorohydrin to prepare cellulose composite hydrogel. After removing inorganic salts by salt-leaching, polyaniline (PANi) with broadband and wide-range light absorption was then integrated into the top surface of hydrogel through in situ polymerization to construct a bi-layer evaporator. As a solar evaporator, the water could be evaporated with a low-energy demand, and the heat from the sunlight could be confined at the interface to achieve efficient water evaporation. Therefore, the hydrogel evaporator demonstrates an optimal water evaporation rate of 3.02 kg m-2 h-1 and photothermal conversion efficiency of 89.09 % under 1 sun (1 kW m-2) irradiation. This work provides new possibilities for efficient solar water purification systems with assured water quality.

14.
Int J Biol Macromol ; 265(Pt 2): 131115, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38522691

RESUMO

A cellulose-reinforced eutectogel was constructed by deep eutectic solvent (DES) and cotton linter cellulose. Cellulose was dispersed in the ternary DES consisting of acrylic acid, choline chloride and AlCl3·6H2O. The photoinitiator was then introduced into the system to in situ polymerize acrylic acid monomer to form transparent and ionic conductive eutectogels while keeping all the DES. The crosslinks formed by Al3+ induced ionic bonds and reversible links formed by hydrogen bonds give the eutectogels high stretchability (3200 ± 200 % tensile strain), self-adhesive (52.1 kPa to glass), self-healing and good mechanical strength (670 kPa). The eutectogels were assembled into sensors and epidermal patch electrodes that demonstrated high quality human motion sensing and physiological signal detection (electrocardiogram and electromyography). This work provides a facile way to design flexible electronics for sensing.


Assuntos
Acrilatos , Celulose , Humanos , Colina , Condutividade Elétrica
15.
Sci Total Environ ; 922: 170736, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38325475

RESUMO

Oil extraction leads to environmental pollution from the oilfields and dweller activities, however, knowledge of the concentration distributions, migration, secondary formation and toxicity of nitrated/oxygenated polycyclic aromatic hydrocarbons (N/OPAHs) in oilfield regions is limited. In this research, atmospheric and soil samples in 7 different location types in an important oil industrial base in China were gathered. The ΣNPAHs and ΣOPAHs in the air ranged from 0.05 to 2.47 ng/m3 and 0.14-22.72 ng/m3, respectively, and in soil ranged from 0.22 to 17.81 ng/g and 9.69-66.86 ng/g, respectively. Both NPAHs and OPAHs in the atmosphere exhibited higher concentrations during winter. The atmospheric NPAH concentrations decreased exponentially with distance from urban area especially in the summer, revealing the impact of vehicles on the air in the Yellow River Delta area. High NPAH and OPAH concentrations were found only in soil near oil extraction facilities, indicating that the impact of oil extraction is limited to the soil near the extraction facilities. The air-soil exchanges of N/OPAHs were assessed through fugacity fraction analysis, and NPAHs were in the equilibrium-deposition state and OPAHs were in the net-deposition state in the winter. Higher incremental lifetime cancer risk (ILCR) occurred at the urban, industrial, and oilfield sites in the atmospheric samples, and the soil samples had the largest ILCR values in the oilfield sites. However, ILCR values for both air and soil did not exceed the threshold of 10-6.

16.
Cell Cycle ; 23(2): 169-187, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38267823

RESUMO

IL-33 has been associated with pro- and anticancer functions in cancer. However, its role in pancreatic cancer metastasis remains unknown. This study aimed to explore the role of miR-548t-5p/IL-33 axis in the metastasis of pancreatic cancer. Luciferase activity assay, qRT-PCR, Western blot and ELISA were performed to prove whether IL-33 is the target of miR-548t-5p. In vivo metastasis assay and cellular transwell assay were performed to explore the role of miR-548t-5p/IL-33 axis in the invasion and metastasis of pancreatic cancer. Co-culture experiments and immunohistochemistry were performed to observe whether IL-33 affects cell invasion and metastasis dependent on the involvement of M2 macrophages. THP-1 cell induction experiment and flow cytometry were performed to explore the effect of IL-33 on macrophage polarization. CCK-8, colony formation, cell apoptosis, cell cycle, cell wound healing and transwell assay were performed to investigate the effect of IL-33 induced M2 macrophages on cell malignant biological behavior by coculturing pancreatic cancer cells with the conditioned medium (CM) from macrophages. We found that miR-548t-5p regulated the expression and secretion of IL-33 in pancreatic cancer cells by directly targeting IL-33 mRNA. IL-33 secreted by cancer cells promoted the recruitment and activation of macrophages to a M2-like phenotype. In turn, IL-33 induced M2 macrophages promoted the migration and invasion of cancer cells. Moreover, IL-33 affected pancreatic cancer cell invasion dependent on the involvement of M2 macrophages in the co-culture system. Thus, our study suggested that manipulation of this IL-33-dependent crosstalk has a therapeutic potential for the treatment of pancreatic cancer metastasis.


Assuntos
Carcinoma Ductal Pancreático , Regulação Neoplásica da Expressão Gênica , Interleucina-33 , Macrófagos , MicroRNAs , Neoplasias Pancreáticas , MicroRNAs/genética , MicroRNAs/metabolismo , Humanos , Interleucina-33/metabolismo , Interleucina-33/genética , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo , Macrófagos/metabolismo , Animais , Linhagem Celular Tumoral , Metástase Neoplásica , Movimento Celular/genética , Invasividade Neoplásica , Camundongos , Apoptose/genética , Técnicas de Cocultura , Camundongos Nus , Proliferação de Células/genética , Células THP-1
17.
Anim Nutr ; 18: 166-176, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39263440

RESUMO

The purpose of this study was to investigate the effects of dietary saccharin sodium supplementation on production performance, serum biochemical indicators, and rumen fermentation of dairy goats in summer. Twelve Guanzhong dairy goats with similar body weight, days in milk, and milk yield were randomly divided into two dietary treatments: (1) CON: basal diet; (2) SS: basal diet + 150 mg/kg saccharin sodium on the basis of dry matter. The experiment lasted 35 d, including 7 d for adaptation and 28 d for dietary treatments, sampling and data collection. Each dairy goat was housed individually in a clean separate pen with ad libitum access to diet and water. The goats fed SS diet had increased dry matter intake (DMI; P = 0.037), 4% fat corrected milk yield (P = 0.049), energy corrected milk yield (P = 0.037), milk protein yield (P = 0.031), and total solids yield (P = 0.036). Serum activity of aspartate aminotransferase (P = 0.047) and concentrations of 70-kDa heat shock protein (P = 0.090), malondialdehyde (P = 0.092), and total protein (P = 0.057) were lower in goats fed SS diet than those fed CON diet. Supplementation of saccharin sodium tended to increase activity of glutathione peroxidase in serum (P = 0.079). The concentrations of rumen total volatile fatty acid (P = 0.042) and butyrate (P = 0.038) were increased by saccharin sodium supplementation. Dietary supplementation of saccharin sodium increased the relative abundance of Lachnobacterium (P = 0.022), Pseudoramibacter (P = 0.022), Shuttleworthia (P = 0.025), and Syntrophococcus (P = 0.037), but reduced the relative abundance of Prevotella_1 (P = 0.037) and Lachnospiraceae_UCG_008 (P = 0.037) in rumen. Saccharin sodium was observed in feces and urine of goats fed diet supplemented with saccharin sodium, but saccharin sodium was undetectable in the milk of goats receiving SS diet. In conclusion, administration of saccharin sodium was effective in increasing fat and energy corrected milk yield by increasing DMI and improving rumen fermentation and antioxidant capacity of dairy goats in summer. In addition, saccharin sodium residue was undetectable in the milk.

18.
Mol Biol Rep ; 40(8): 4913-20, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23813057

RESUMO

The human mucin 4 (MUC4) is aberrantly expressed in pancreatic adenocarcinoma and tumor cell lines, while remaining undetectable in normal pancreas, indicating its important role in pancreatic cancer development. Although its transcriptional regulation has been investigated in considerable detail, some important elements remain unknown. The aim of the present study was to demonstrate the existence of a novel inhibitory element in the MUC4 promoter and characterize some of its binding proteins. By luciferase reporter assay, we located the inhibitory element between nucleotides -2530 and -2521 in the MUC4 promoter using a series of deletion and mutant reporter constructs. Electrophoretic mobility shift assay (EMSA) with Bxpc-3 cell nuclear extracts revealed that one protein or protein complex bind to this element. The proteins binding to this element were purified and identified as Yin Yang 1 (YY1) by mass spectrometry. Supershift assay and chromatin immunoprecipitation (ChIP) assay confirmed that YY1 binds to this element in vitro and in vivo. Moreover, transient YY1 overexpression significantly inhibited MUC4 promoter activity and endogenous MUC4 protein expression. In conclusion, we reported here a novel inhibitory element in the human MUC4 promoter. This provides additional data on MUC4 gene regulation and indicates that YY1 may be a potential target for abnormal MUC4 expression.


Assuntos
Regulação da Expressão Gênica/genética , Mucina-4/metabolismo , Regiões Promotoras Genéticas/genética , Fator de Transcrição YY1/metabolismo , Western Blotting , Linhagem Celular Tumoral , Imunoprecipitação da Cromatina , Ensaio de Desvio de Mobilidade Eletroforética , Humanos , Luciferases , Espectrometria de Massas , Mucina-4/genética , Oligonucleotídeos/genética , Plasmídeos/genética
19.
Int J Biol Macromol ; 230: 123425, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36706872

RESUMO

Ionic conducting hydrogels (ICHs) are emerging materials for multi-functional sensors in the fields of healthcare monitoring and flexible electronics. However, there is a long-standing dilemma between ionic conductivity and mechanical properties of the ICHs. In this work, ionic conductive, flexible, transparent, and anti-freezing hydrogels are fabricated by dissolving cotton linter pulp in ZnCl2/CaCl2 solution and cross-linking with epichlorohydrin (ECH). The presence of inorganic salt imparts the hydrogel with high ionic conductivity and low-temperature tolerance. While the introduction of ECH as the second network gives the hydrogel with desirable mechanical performance. By tailoring the ECH addition, the tensile strength, compressive strength, elongation at break, and conductivity of the hydrogel could reach 0.82 MPa, 2.80 MPa, 260 %, and 5.48 S m-1, respectively. The prepared ICHs are fabricated into sensors for detecting full-range human body motions, and they demonstrate fast response and durable sensitivity to both tensile strain and compressive deformation. Moreover, flexible sensors can work at subzero temperatures. This work provides a new idea for the preparation of cellulose-based hydrogels with good ionic conductivity and mechanical properties under extreme conditions.


Assuntos
Celulose , Hidrogéis , Humanos , Temperatura Baixa , Força Compressiva , Condutividade Elétrica , Epicloroidrina
20.
Carbohydr Polym ; 319: 121161, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37567705

RESUMO

Hydrogels are emerging materials for solar steam generation to alleviate water scarcity. Herein, a semiconductor of copper sulfide (CuS) was integrated into cellulose hydrogel to fabricate a solar steam evaporator. Sustainable and low-cost cotton linter (cellulose) was regenerated by NaOH/urea solvent. Epichlorohydrin was added as a cross-linking agent to enhance the mechanical robustness of the composite hydrogel, and CuS crystals were tightly attached to cellulose fibers and uniformly distributed in the hydrogel matrix. Under simulated solar light, a heating zone was established at the top surface of the composite hydrogel, and CuS can efficiently absorb and convert light into heat. The hydrophilic cellulose network affords an adequate water supply and a low water vaporization enthalpy. By tuning the CuS loadings, the optimized evaporation rate and solar-to-vapor efficiency could reach 2.2 kg/m2/h and 87 %, respectively, under 1 sun irradiation. The evaporation rate remained above 2.1 kg/m2/h after 48 h of irradiation. Moreover, the hydrogels (with a CuS loading of 30 wt%) showed a efficiently photocatalytic degradation of 95 % for methylene blue and 92 % for Rhodamine B. Such functional hydrogel evaporator holds great potential for practical water treatment and solar-driven applications.

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