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1.
Environ Sci Pollut Res Int ; 31(24): 35688-35704, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38740681

RESUMO

In this work, iron-phosphorus based composite biochar (FPBC) was prepared by modification with potassium phosphate and iron oxides for the removal of heavy metal ions from single and mixed heavy metal (Pb and Cd) solutions. FTIR and XPS characterization experiments showed that the novel modified biochar had a greater number of surface functional groups compared to the pristine biochar. The maximum adsorption capacities of FPBC for Pb(II) and Cd(II) were 211.66 mg·g-1 and 94.08 mg·g-1 at 293 K. The adsorption of Pb(II) and Cd(II) by FPBC followed the proposed two-step adsorption kinetic model and the Freundlich isothermal adsorption model, suggesting that the mechanism of adsorption of Pb(II) and Cd(II) by FPBC involved chemical adsorption of multiple layers. Mechanistic studies showed that the introduction of -PO4 and -PO3 chemisorbed with Pb(II) and Cd(II), and the introduction of -Fe-O increased the ion exchange with Pb(II) and Cd(II) during the adsorption process and produced precipitates such as Pb3Fe(PO4)3 and Cd5Fe2(P2O7)4. Additionally, the abundant -OH and -COOH groups also participated in the removal of Pb(II) and Cd(II). In addition, FPBC demonstrated strong selective adsorption of Pb(II) in mixed heavy metal solutions. The Response Surface Methodology(RSM) analysis determined the optimal adsorption conditions for FPBC as pH 5.31, temperature 26.01 °C, and Pb(II) concentration 306.30 mg·L-1 for Pb(II). Similarly, the optimal adsorption conditions for Cd(II) were found to be pH 5.66, temperature 39.34 °C, and Cd(II) concentration 267.68 mg·L-1. Therefore, FPBC has the potential for application as a composite-modified adsorbent for the adsorption of multiple heavy metal ions.


Assuntos
Cádmio , Carvão Vegetal , Chumbo , Fósforo , Poluentes Químicos da Água , Adsorção , Carvão Vegetal/química , Cádmio/química , Chumbo/química , Poluentes Químicos da Água/química , Fósforo/química , Ferro/química , Cinética , Purificação da Água/métodos , Metais Pesados/química
2.
Nanomedicine (Lond) ; 19(10): 841-854, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38436253

RESUMO

Aims: Preparation and evaluation of nanoparticles for tumor chemotherapy and immunotherapy mild photothermal therapy and oxaliplatin. Methods: The double emulsion method was used for nanoparticle preparations. Polydopamine was deposited on the surface, which was further modified with folic acid. Cytotoxicity assays were carried out by cell counting kit-8. In vivo antitumor assays were carried out on 4T1 tumor-bearing mice. Results: The nanoparticles exhibited a 190 nm-diameter pomegranate-like sphere, which could increase temperature to 43-46°C. In vivo distribution showed enhanced accumulation. The nanoparticles generated stronger immunogenic cell death effects. By stimulating the maturation of dendritic cells, mild photothermal therapy combined with oxaliplatin significantly increased the antitumor effect by a direct killing effect and activation of immunotherapy. Conclusion: This study provided a promising strategy of combination therapy for tumors.


Assuntos
Hipertermia Induzida , Nanopartículas , Neoplasias , Animais , Camundongos , Oxaliplatina/uso terapêutico , Terapia Fototérmica , Fototerapia/métodos , Neoplasias/tratamento farmacológico , Imunoterapia , Linhagem Celular Tumoral
3.
Int J Biol Macromol ; 241: 124668, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37121413

RESUMO

Carboxymethyl chitosan (CMCS) has antibacterial activity and coating-forming ability. Under the impact of noncovalent interactions, the bioactivity and functionality of CMCS may be positively affected by the coexistence of flavonoids. This study investigated the effect of a CMCS coating incorporated with flavonoids from guava (Psidium guajava L. cv. Carmine) leaf (GLF) on the refrigeration of fresh-cut apples for preservation. Compared with the CMCS group, apples treated with the CMCS-GLF coating showed better quality (weight loss, browning index, firmness), nutritional value (ascorbic acid and total phenolic content), and microbial safety during storage. The mechanism study indicated that the hydrogen bonding, electrostatic, and hydrophobic interactions between CMCS and GLF (the carboxymethyl moiety of CMCS had the highest response priority and binding strength of the interaction with -C-O of GLF) changed the surface charge distribution and microstructure of CMCS, and increased its molecular weight, particle size, viscosity, and hydrophobicity. Thus, the CMCS-GLF coating exerted better bioactivities (antibacterial and antioxidant activity), and its film showed better mechanical and barrier properties. These results revealed that the noncovalent interaction with GLF could modify the physiochemical properties of CMCS, which was beneficial to improve its bioactivity and application value in fresh fruit preservation.


Assuntos
Quitosana , Malus , Psidium , Flavonoides/farmacologia , Quitosana/química , Antibacterianos/farmacologia
4.
Carbohydr Polym ; 298: 120105, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36241282

RESUMO

The non-covalent binding between flavanols and polysaccharides has impacts on their bioactivities, but the binding mechanism is less understood. This work aimed to unveil the non-covalent interactions between epicatechin gallate (ECG) and anionic carboxymethyl Poria cocos polysaccharide (CMPN) at the structural and molecular level based on the synergistic antibacterial effect between them. The results suggested that there was hydrogen bonding, hydrophobic and electrostatic interaction between ECG and CMPN, which was also supported by the results of molecular dynamics simulations. The resulting changes in physicochemical properties enhanced the antibacterial activity of the ECG-CMPN mixture. More specifically, through two-dimensional Fourier transform infrared correlation spectrum (2D-FT-IR) and nuclear magnetic resonance spectroscopy (NMR) analysis, COO- in CMPN carboxymethyl and CO in ECG galloyl had the highest response priority and binding strength in the interaction, allowing us to conclude the critical functional groups that affect the non-covalent interactions of polysaccharide and flavanols and their bioactivities.


Assuntos
beta-Glucanas , Antibacterianos/farmacologia , beta-Glucanas/química , Catequina/análogos & derivados , Polissacarídeos/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier
5.
J Exp Bot ; 73(1): 123-138, 2022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-34490889

RESUMO

The formation of locule gel is an important process in tomato and is a typical characteristic of berry fruit. In this study, we examined a natural tomato mutant that produces all-flesh fruit (AFF) in which the locule tissue remains in a solid state during fruit development. We constructed different genetic populations to fine-map the causal gene for this trait and identified SlMBP3 as the locus conferring the locule gel formation, which we rename as AFF. We determined the causal mutation as a 416-bp deletion in the promoter region of AFF, which reduces its expression dosage. Generally, this sequence is highly conserved among Solanaceae, as well as within the tomato germplasm. Using BC6 near-isogenic lines, we determined that the reduced expression dosage of AFF did not affect the normal development of seeds, whilst producing unique, non-liquefied locule tissue that was distinct from that of normal tomatoes in terms of metabolic components. Combined analysis using mRNA-seq and metabolomics indicated the importance of AFF in locule tissue liquefaction. Our findings provide insights into fruit-type differentiation in Solanaceae crops and also present the basis for future applications of AFF in tomato breeding programs.


Assuntos
Solanum lycopersicum , Frutas/genética , Solanum lycopersicum/genética , Mutação , Melhoramento Vegetal , Regiões Promotoras Genéticas
6.
Diabetes Res Clin Pract ; 174: 108743, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33713718

RESUMO

AIMS: To investigate the therapeutic effect of continuous diffusion of oxygen (CDO) combined with traditional moist wound dressing (MWD) on the diabetic foot ulcers (DFUs) inpatients. METHODS: The inpatients from May 2016 to April 2018 were enrolled and randomly divided into MWD, CDO and combination treatment groups (n = 40 each group). The moist dressing was used in the MWD group while a micro-oxygen supply device was used in the CDO group. The combination treatment group was given both MWD and CDO. All patients were treated for 8 weeks. The wound healing, amputation rate, and inflammatory control were evaluated. RESULTS: Compared with MWD and CDO groups, the combination group showed a higher wound healing rate (P < 0.05), lower white blood cell count (P < 0.05) and lower high-sensitivity C-reactive protein level (P < 0.05). During 1-year follow-up, the amputation rate was 0% in combination group, which was significantly lower than that in other two groups (P < 0.05). CONCLUSIONS: The combination of MWD and CDO was effective in promoting healing and preventing infection of DFUs, which holds a potential to be a new strategy for the treatment of this critical clinical condition.


Assuntos
Bandagens/normas , Desbridamento/métodos , Pé Diabético/terapia , Oxigênio/uso terapêutico , Cicatrização/fisiologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
7.
Front Cell Infect Microbiol ; 10: 618747, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33680984

RESUMO

In total, 49 clinical samples were analyzed using two typing schemes, Enhanced Centers for Disease Control and Prevention (ECDC) and multilocus sequence typing (MLST), to describe the molecular characteristics of circulating Treponema pallidum isolates in Xiamen between 2016 and 2017. In addition, genetic mutations potentially related to antibiotic resistance of T. pallidum were also analyzed. Forty five samples were fully typed by ECDC, and 14 different subtypes were detected. The most common subtype was 16d/f (24.4%), followed by 14d/f (20.0%). All forty nine samples were successfully typed by MLST, while only four allelic profiles were identified, including three SS14-like profiles and one Nichols-like profile. Among them, the major allelic profile was 1.1.8 (85.7%). Interestingly, the allelic profile 1.3.1 widespread in Europe and North America was not detected in this region. Additionally, A2058G mutation in 23S rRNA was found in all detectable samples (38/38), and no mutation in 16S rRNA was observed (36/36). Four non-synonymous single-nucleotide polymorphisms in penicillin-binding protein genes were found in the 35 samples eligible for Sanger sequencing. Among them, the variant in tp0500 (P564I) can only be found in the SS14-like isolates. Homoplastic changes in tp0760 (I415F/I415M) and tp0705 (A506V/A506T) were found. Moreover, the variant tp0705 A506V and the variant tp0705 A506T separately appeared in the SS14-like isolates and Nichols-like isolates, respectively. This study showed that the genotypes of T. pallidum isolates in Xiamen between 2016 and 2017 were different from those in other geographic areas. The resistance-related variants of T. pallidum isolates identified in this study could provide awareness for clinicians in the treatment of syphilis.


Assuntos
Tipagem de Sequências Multilocus , China , Resistência Microbiana a Medicamentos , Europa (Continente) , Tipagem Molecular , América do Norte , RNA Ribossômico 16S , Treponema
8.
Environ Sci Pollut Res Int ; 26(14): 13878-13895, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30645742

RESUMO

This study estimates the carbon emission intensity of China's provinces during the period from 2000 to 2015. First, the temporal and spatial pattern evolution of China's carbon emission intensity was analyzed using spatial statistics. Then, from an innovation-driven perspective, combining the data of innovative technologies and scale factors to construct a spatial panel model to explore the main influencing factors of carbon emission intensity and its spatial spillover effect. The results show that: China's provincial carbon emission intensity has obvious spatial agglomeration characteristics, and regional differences are improving, and the spatial spillover effect of some influencing factors is obvious; innovation indicators such as the number of patent authorizations, technical market turnover, and foreign direct investment, and GDP have a significant negative impact on carbon intensity, and the effects of general scale variables such as urbanization rate, energy consumption, and population density on carbon intensity are significantly positive.


Assuntos
Carbono/análise , Invenções/economia , Modelos Econométricos , Dióxido de Carbono/análise , China , Gases de Efeito Estufa/análise , Humanos , Investimentos em Saúde , Densidade Demográfica , Análise Espacial , Urbanização
9.
J Biomed Nanotechnol ; 14(12): 2185-2197, 2018 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-30305225

RESUMO

The mechanism of Mycobacterium tuberculosis (M.tb) evasion of host cell remains elusive. Several microRNAs that are involved in this complex process were identified. miRNA interference-based therapeutics represents an attractive challenge and shows huge potential for disorder treatment. In this study, we found that miR-124-3p expression is significantly decreased in microglia after Mycobacterium marinum (M.m) infection. To achieve better target transfection effect, a CD11b antibody and PEI modified nanoparticles-based Nano platform had been developed. This system was equipped by conjugation of miRNA-124-3p onto the surface of nanoparticles with a PEI/CD11b antibody coating. Transfection with miR-124-3p promoted microglia apoptosis through upregulation of Caspase3 or downregulation of Bcl-2 and Bcl-xl. More importantly, transfection with miR-124-3p inhibitor increases the mycobacterium proliferation in microglia. Based on the above, we further found miRNA-124-3p to bind to 3'untranslated region of Stat3, resulting in the downregulation of its protein to trigger cells apoptosis through Stat3-related pathway. As such, our research might provide new insights towards target delivering miRNA through the bold-brain barrier (BBB) and exploiting highly effective anti-tuberculous meningitis drugs. Taken together, our findings suggest how Mycobacterium can manipulate host miRNA expression to regulate cell survival for its own proliferation, and highlight the importance to develop novel therapeutic strategies against tuberculous meningitis.


Assuntos
Mycobacterium , Nanopartículas , Anticorpos , Apoptose , Linhagem Celular Tumoral , Humanos , MicroRNAs , Microglia , Fator de Transcrição STAT3
10.
Opt Express ; 23(23): 29360-8, 2015 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-26698420

RESUMO

In this paper, systematical study on the focal shift phenomenon in planar lenses based on GaN high contrast gratings was performed using finite element method (FEM). Influence of parameters including device size, designed focal length, total phase difference on the focusing performance is presented. It shows that the focal shift is mainly determined by the Fresnel number of the lens, which is nearly equal to the total phase difference divided by π. The influence of the lens size and designed focal length can be attributed to the change of Fresnel number. Theoretical analysis based on diffraction theory is employed to predict the focal shift, which is in accordance with the numerical simulation.

11.
Opt Express ; 22(1): 667-72, 2014 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-24515026

RESUMO

We present here the fabrication of subwavelength GaN membrane grating with a double-side process. Controllable GaN membrane thickness is achieved by backside thinning technique, which is essential to realize guided-mode resonant GaN grating in the visible range. Subwavelength GaN grating can serve as an optical resonator and accommodate surface-normal emission coupling. The measured photoluminescence (PL) spectra are sensitive to the parameters and shapes of GaN gratings. Both numerical simulation and reflectivity measurement are in consistent with the PL experimental results. This work opens a promising way to embed GaN-based photon emitter inside subwavelength grating to further produce a surface emitting device with a single layer GaN grating.

12.
Respirology ; 17(6): 997-1005, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22616553

RESUMO

BACKGROUND AND OBJECTIVE: Moxifloxacin (MXF) has been shown to possess immunomodulatory properties in addition to its antimicrobial effects. We investigated the effects of MXF on cytokine secretion and signal transduction mechanisms in naive control and allergen-exposed airway smooth muscle cell (ASMC) stimulated with tumour necrosis factor (TNF)-α. METHODS: An animal model was established. ASMC was derived from rat airway tissue and cultured in vitro, then incubated with 10 ng/mL of TNF-α. Interleukin (IL)-8 and eotaxin secretion were measured by enzyme-linked immunosorbent assay, and activation of extracellular-signal-regulated kinase (ERK)1/2 and nuclear factor (NF)-κB p65 was measured by western blotting, with or without the addition of MXF (20 µg/mL) and/or dexamethasone (DXM) (10(-6) M). RESULTS: Baseline IL-8 and eotaxin secretion did not differ between control and allergen-exposed cells. Stimulation with TNF-α increased IL-8 and eotaxin secretion, with increased IL-8 secretion by allergen-exposed compared with naive control ASMC, post-TNF-α stimulation (P = 0.001). Baseline phosphorylation of ERK1/2 (p-ERK1/2) and NF-κB p65 was higher in allergen-exposed than in control ASMC. TNF-α increased p-ERK1/2 and NF-κB p65 levels, with higher levels in allergen-exposed ASMC, post-TNF-α stimulation (P < 0.001). MXF and the combination of MXF with DXM suppressed the secretion of IL-8 and eotaxin, but DXM alone did not affect IL-8, post-TNF-α stimulation (P > 0.05). MXF, DXM and the combination of MXF with DXM inhibited TNF-α-stimulated p-ERK1/2 and NF-κB p65 levels by 34, 40 and 62%, and 33, 38 and 64%, respectively. CONCLUSIONS: MXF suppressed the secretion of pro-inflammatory cytokines by allergen-exposed rat ASMC, partly by inhibiting NF-κB and ERK activation. DXM may have additional or synergistic effects with MXF.


Assuntos
Alérgenos/imunologia , Anti-Infecciosos/farmacologia , Anti-Inflamatórios/farmacologia , Compostos Aza/farmacologia , Quimiocina CCL11/biossíntese , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , Interleucina-8/biossíntese , Miócitos de Músculo Liso/efeitos dos fármacos , NF-kappa B/metabolismo , Quinolinas/farmacologia , Animais , Asma/tratamento farmacológico , Asma/metabolismo , Células Cultivadas , Quimiocina CCL11/metabolismo , Dexametasona/farmacologia , Modelos Animais de Doenças , Fluoroquinolonas , Moxifloxacina , Ratos , Fator de Necrose Tumoral alfa/farmacologia
13.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 27(8): 849-51, 2011 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-21806880

RESUMO

AIM: To explore the effect of leptin on the proliferation of rat airway smooth muscle cells(ASMCs) and its possible mechanism. METHODS: ASMCs were derived from rat airway tissue and cultured in vitro. RT-PCR and Western blot were used to verify the expression of leptin receptors on ASMCs. And then ASMCs were treated with leptin at different concerntrations (0-100 µg/L) for different periods of time (1-72 h), respectively. Cell proliferation was measured by CCK-8 assay. The expression of p-ERK and PI-3K in ASMCs were quantified by Western blot after being treated with leptin at different concentrations. RESULTS: Leptin of various concentrations was used to treat different time could promote the proliferation of ASMCs in dose-dependent manner (r=0.837, P<0.01)and time-dependent manner (r=0.874, P<0.01). Western bot indicated that the expression of p-ERK and PI-3K increased with the increase of leptin concerntrations (P<0.05). The expression of p-ERK and PI-3K was a positive correlation with the concerntrations of leptin (r=0.793, P<0.01; r=0.746, P<0.01). CONCLUSION: Leptin can significantly stimulate ASMCs proliferation and its mechanism may be correlated to activation of p-ERK and PI-3K.


Assuntos
Leptina/farmacologia , Miócitos de Músculo Liso/efeitos dos fármacos , Sistema Respiratório/efeitos dos fármacos , Sistema Respiratório/metabolismo , Animais , Proliferação de Células/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Miócitos de Músculo Liso/citologia , Miócitos de Músculo Liso/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , RNA Mensageiro/genética , Ratos , Receptores para Leptina/genética , Receptores para Leptina/metabolismo
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