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1.
Int J Biol Macromol ; 270(Pt 1): 132142, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38719005

RESUMO

The severe negative effects of impurities adhering to the external surface of wearable devices can significantly influence the signal transmission, performance, and lifespan of hydrogel sensors. Herein, we developed an ion-conducting hydrogel sensor with a strong adhesive side and a non-adhesive side, similar to a "semi-releasing material." This hydrogel, formulated using deep eutectic solvents obtained from choline chloride and acrylic acid, contained lignin. This versatile material, exhibiting properties similar to semi-releasing materials, was treated with an AlCl3 solution on one side. Additionally, the hydrogel was successfully used as a highly adhesive strain sensor for real-time monitoring of various human activity signals. Moreover, the hydrogel demonstrated excellent environmental tolerance and conductivity. Lignin extracted from wood flour endowed the hydrogel sensor with excellent adhesion energy (up to 427.1 J/m2) and UV resistance. Treatment of hydrogels with AlCl3 completely eliminated their adhesiveness, thereby enhancing fracture elongation and tensile strength. This improvement can be attributed to the absence of carboxyl groups and the formation of a metal-phenolic network. The implementation of this convenient and efficient strategy provides a more feasible approach to address challenges related to impurity adhesion and signal transmission in flexible wearable devices.


Assuntos
Hidrogéis , Lignina , Dispositivos Eletrônicos Vestíveis , Lignina/química , Hidrogéis/química , Humanos , Condutividade Elétrica , Resistência à Tração , Cloreto de Alumínio/química , Íons/química
2.
Environ Monit Assess ; 195(4): 527, 2023 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-37000307

RESUMO

The application of the coagulation/flocculation process is very important due to its simplicity in removing turbidity. Due to the disadvantages of using chemical coagulants in water and the lack of sufficient effect of natural materials alone in removing turbidity for proper performance, the simultaneous use of chemical and natural coagulants is the best way to reduce the harmful effects of chemical coagulants in water. In this study, the application of poly aluminum chloride (PAC) as a chemical coagulant and rice starch as a natural coagulant aid to remove turbidity from aqueous solutions was investigated. Effects of the above coagulants on the four main factors, coagulant dose (0-10 mg/L), coagulant adjuvant dose (0-0.1 mg/L), pH (5-9), turbidity (NTU 0-50), and each five levels were assessed using a central composite design (CCD). Under the optimized conditions, the maximum turbidity elimination efficiency was found to be 96.6%. The validity and adequacy of the proposed model (quadratic model) were confirmed by the corresponding statistics (i.e., F-value of 23.3, p-values of 0.0001, and lack of fit of 0.877 for the model, respectively, R2 = 0.88, R2adj. = 0.84, R2 pred = 0.79, AP = 22.04).


Assuntos
Purificação da Água , Cloreto de Alumínio/química , Floculação , Oryza , Amido/química , Água , Purificação da Água/métodos , Modelos Químicos
3.
J Photochem Photobiol B ; 222: 112256, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34330080

RESUMO

Photobiomodulation (PBM) is a promising medical treatment modality in the area of photodynamic therapy (PDT). In this study, we investigated the effect of combined therapy in a 3D microenvironment using aluminum chloride phthalocyanines (AlClPc) as the photosensitizing agent. Normal human fibroblast-containing collagen biomatrix was prepared and treated with an oil-in-water (o/a) AlClPc-loaded nanoemulsion (from 0.5 to 3.0 µM) and irradiated at a range of fluences (from 0.1 to 3.0 J/cm2) using a continuous-wave light-emitting diode (LED) irradiation system (660 nm). PBM at 1.2 J/cm2 and AlClPc/NE at 0.5 µM modified the fibroblast signaling response under 3D conditions, promoting collagen synthesis, ROS production, MMP-9 secretion, proliferation of the actin network, and facile myofibroblastic differentiation. PBM alone (at 1.2 J/cm2 and 0.3 J/cm2) had no significant effect on any of these parameters. The combined therapy affected myofibroblastic differentiation, inflammatory response, and extracellular matrix pliability, and should thus be examined further in subsequent studies considering that no side effects of PBM have been reported. Even though significant progress has been made in the field of phototherapy in recent years, it is necessary to further elucidate the detailed mechanisms underlying its effects already shown in 2D conditions to increase the acceptance of this beneficial and non-invasive therapeutic approach.


Assuntos
Cloreto de Alumínio/farmacologia , Fibroblastos/efeitos dos fármacos , Indóis/farmacologia , Luz , Compostos Organometálicos/farmacologia , Fármacos Fotossensibilizantes/farmacologia , Cloreto de Alumínio/química , Técnicas de Cultura de Células , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Células Cultivadas , Colágeno/metabolismo , Fibroblastos/citologia , Fibroblastos/metabolismo , Fibroblastos/efeitos da radiação , Humanos , Indóis/química , Metaloproteinase 9 da Matriz/metabolismo , Compostos Organometálicos/química , Fármacos Fotossensibilizantes/química , Espécies Reativas de Oxigênio/metabolismo
4.
Sci Rep ; 11(1): 12040, 2021 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-34103557

RESUMO

Peganum harmala (P. harmala) is a folk medicinal herb used in the Sinai Peninsula (Egypt) as a remedy for central disorders. The main constituents, harmine and harmaline, have displayed therapeutic efficacy against Alzheimer's disease (AD); however, the P. harmala potential on sensitizing central insulin to combat AD remains to be clarified. An AD-like rat model was induced by aluminum chloride (AlCl3; 50 mg/kg/day for six consecutive weeks; i.p), whereas a methanolic standardized P. harmala seed extract (187.5 mg/kg; p.o) was given to AD rats starting 2 weeks post AlCl3 exposure. Two additional groups of rats were administered either the vehicle to serve as the normal control or the vehicle + P. harmala seed extract to serve as the P. harmala control group. P. harmala enhanced cognition appraised by Y-maze and Morris water maze tests and improved histopathological structures altered by AlCl3. Additionally, it heightened the hippocampal contents of glucagon-like peptide (GLP)-1 and insulin, but abated insulin receptor substrate-1 phosphorylation at serine 307 (pS307-IRS-1). Besides, P. harmala increased phosphorylated Akt at serine 473 (pS473-Akt) and glucose transporter type (GLUT)4. The extract also curtailed the hippocampal content of beta amyloid (Aß)42, glycogen synthase (GSK)-3ß and phosphorylated tau. It also enhanced Nrf2, while reduced lipid peroxides and replenished glutathione. In conclusion, combating insulin resistance by P. harmala is a novel machinery in attenuating the insidious progression of AD by enhancing both insulin and GLP-1 trajectories in the hippocampus favoring GLUT4 production.


Assuntos
Cloreto de Alumínio/química , Doença de Alzheimer/tratamento farmacológico , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo , Insulina/metabolismo , Peganum/metabolismo , Peptídeos beta-Amiloides/metabolismo , Animais , Comportamento Animal , Cognição , Modelos Animais de Doenças , Progressão da Doença , Glicogênio Sintase Quinase 3 beta/metabolismo , Harmalina/uso terapêutico , Hipocampo/metabolismo , Resistência à Insulina , Masculino , Aprendizagem em Labirinto , Neurociências , Peganum/química , Fosforilação , Plantas Medicinais/metabolismo , Ratos , Ratos Wistar , Transdução de Sinais
5.
Int J Biol Macromol ; 184: 200-208, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34126151

RESUMO

To develop the hydrogels with high mechanical strength and excellent conductivity is always a challenging topic. In this study, the ultra-strong hydroxypropyl cellulose (HPC)/polyvinyl alcohol (PVA) composite hydrogels were prepared by combination of the triple-network and mechanical training. The proposed composite hydrogels were achieved by physically crosslinking HPC with PVA to form the first crosslinking network, in which the HPC fibers could decrease the crosslinking density of PVA matrix and generate a lot of water-rich porous area. Then, 2-hydroxyethyl acrylate (HEA), acrylamide (AM) and aluminium chloride diffused into the first network to fabricate the chemical crosslinking network and ionically cross-linked domains. The formation of triple-network enhanced the mechanical strength and toughness to 1.87 MPa and 339.09 kJ/m3, respectively. Especially, the crystalline domains of PVA chains could improve the hydrogel's fatigue resistance, and the orderly arrangement of the crystalline domains achieved through mechanical training process could further enhance the mechanical strength. The mechanical strength of pre-stretched composite hydrogel was increased up to 2.8 MPa. The composite hydrogels exhibit great applications in sensors, human-machine interactions, and wearable devices.


Assuntos
Acrilamida/química , Acrilatos/química , Cloreto de Alumínio/química , Celulose/análogos & derivados , Álcool de Polivinil/química , Celulose/química , Cristalografia , Condutividade Elétrica , Hidrogéis , Teste de Materiais , Porosidade , Resistência à Tração , Dispositivos Eletrônicos Vestíveis
6.
Molecules ; 25(24)2020 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-33348758

RESUMO

Tea is rich in catechins and aluminum. In this study, the process of catechin photolysis was applied as a model for examining the effects of aluminum chloride (AlCl3) on the structural changes of catechin and the alteration of aluminum complexes under blue light irradiation (BLI) at pH 8 using liquid chromatography and mass spectrometry techniques. Additionally, the effects of anions on catechin upon the addition of AlCl3 and treatment with BLI were also studied. In this study, when 1 mM catechin was treated with BLI, a superoxide anion radical (O2•-) was generated in an air-saturated aqueous solution, in addition to forming a dimeric catechin (proanthocyanidin) via a photon-induced redox reaction. The relative percentage of catechin was found to be 59.0 and 95.7 for catechin treated with BLI and catechin upon the addition of 1 mM AlCl3 treated with BLI, respectively. It suggested that catechin treated with BLI could be suppressed by AlCl3, while AlCl3 did not form a complex with catechin in the photolytic system. However, under the same conditions, it was also found that the addition of AlCl3 inhibited the photolytic formation of O2•-, and reduced the generation of proanthocyanidin, suggesting that the disconnection of proanthocyanidin was achieved by AlCl3 acting as a catalyst under treatment with BLI. The influence of 1 mM fluoride (F-) and 1 mM oxalate (C2O42-) ions on the photolysis of 1 mM catechin upon the addition of 1 mM AlCl3 and treatment with BLI was found to be insignificant, implying that, during the photolysis of catechin, the Al species were either neutral or negatively charged and the aluminum species did not form a complex with anions in the photolytic system. Therefore, aluminum, which is an amphoteric species, has an inherent potential to stabilize the photolysis of catechin in an alkaline conditions, while suppressing the O2•- and proanthocyanidin generation via aluminum ion catalysis in the catechin/Al system under treatment with BLI.


Assuntos
Cloreto de Alumínio/química , Catequina/química , Fotólise , Proantocianidinas/química , Superóxidos/química , Alumínio/química , Cromatografia Líquida , Luz , Espectrometria de Massas , Plantas/química , Chá/química
7.
IET Nanobiotechnol ; 14(7): 590-594, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33010134

RESUMO

Cellulosic coagulant with low crystallinity and surface charge of -19.2 mV were extracted from wet banana peels (WBE) using kitchen-blending method. Functionalization with ferric chloride and aluminium chloride yielded higher surface charge of -23.8 mV (mWBE). Both WBE and mWBE coagulants were used to target cadmium ions from aqueous solution. Coagulants and the floccules (WBEA and mWBEA) were characterized by XRD, FT-IR, zeta sizer nano series, and SEM/EDs. The amount of cadmium ion coagulated was determined using ICP-OES. The FTIR analysis revealed the functional groups involved in the coordination and subsequent removal of the metals ions around 1634 cm-1, ascribed to the C = O vibrational band of carbonyl group. Microscopic analysis revealed that the mWBE is porous and exhibited microfibers with rod-like morphology. The effects of parameters such as the initial concentration, coagulant dosage and solution pH were investigated. Coagulation results showed that 10 mg of WBE and mWBE could remove about 80% and 90% of the Cd2+ ions respectively. However; the difference in the performance of both materials does not justify the essence of surface modification. Therefore, WBE is considered more efficient and environmentally friendly. Notwithstanding, the performance of these coagulants in real environmental samples will confirm their robustness.


Assuntos
Cloreto de Alumínio/química , Celulose/química , Cloretos/química , Compostos Férricos/química , Adsorção , Cádmio/química , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Varredura , Musa , Porosidade , Espectroscopia de Infravermelho com Transformada de Fourier , Eliminação de Resíduos Líquidos/métodos , Água/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Difração de Raios X
8.
Bioorg Chem ; 104: 104216, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32911191

RESUMO

The article is devoted to the targeted synthesis and study of cyclic thiourea and their various new derivatives as new organic compounds containing polyfunctional group in the molecule. First time the reaction of the corresponding synthesized pyrimidinethione with 1,2-epoxy-3-chlorpropane at the presence of AlCl3 catalyst in 75-80% yield alkyl-1-(3-chloro-2-hydroxypropyl)-4-alkyl-6-phenyl-2-thioxo-1,2,5,6- tetrahydropyrimidine-5-carboxylates. In the next stage, new cyclic thiourea derivatives of aminoalcohols were synthesised from the reaction of chlorinated derivatives of pyrimidinethiones with single amines and their structures were investigated by spectroscopic methods. In this study, a series of novel compounds were tested towards some metabolic enzymes including α-glycosidase (α-Gly) and α-amylase (α-Amy) enzymes. Novel compounds showed Kis in ranging of 10.43 ± 0.94-111.37 ± 13.25 µM on α-glycosidase and IC50 values in ranging of 14.38-106.51 µM on α-amylase. The novel cyclic thiourea derivatives of aminoalcohols had effective inhibition profiles against all tested metabolic enzymes. Binding affinity and inhibition mechanism of the most active compounds were detected with in silico studies and have shown that 2-Hydroxypropyl and butan-1-aminium moieties play a key role for inhibition of the enzymes.


Assuntos
Cloreto de Alumínio/química , Amino Álcoois/farmacologia , Inibidores de Glicosídeo Hidrolases/farmacologia , Glicosídeo Hidrolases/antagonistas & inibidores , Tioureia/farmacologia , alfa-Amilases/antagonistas & inibidores , Amino Álcoois/química , Catálise , Relação Dose-Resposta a Droga , Inibidores de Glicosídeo Hidrolases/síntese química , Inibidores de Glicosídeo Hidrolases/química , Glicosídeo Hidrolases/metabolismo , Humanos , Simulação de Acoplamento Molecular , Estrutura Molecular , Saccharomyces cerevisiae/enzimologia , Relação Estrutura-Atividade , Tioureia/síntese química , Tioureia/química , alfa-Amilases/metabolismo
9.
J Trace Elem Med Biol ; 62: 126631, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32763766

RESUMO

BACKGROUND: Aluminum (Al) has been reported to induce testicular injury via oxidative stress. Ananas comosus stem extract is an inexpensive byproduct waste rich in bromelain which is a group of sulfur-containing enzymes known for its biological activities and medicinal applications. So, the current investigation aims to evaluate the efficacy of bromelain in counteracting oxidative injury and testicular dysfunction stimulated by aluminum in rats. METHODS: Male adult Wistar rats were divided into four groups. The first group used as control, however, the second and third groups were received bromelain (250 mg/kg) and AlCl3 (34 mg/Kg, 1/25 LD50), and the fourth group supplemented with bromelain one hour before AlCl3 intoxication, respectively. Bromelain was administered daily while AlCl3 was given every other day by oral gavages for one month. RESULTS: Al intoxicated animals revealed an elevation in lipid peroxidation (TBARS and H2O2) level and lactate dehydrogenase (LDH) activity. However, reduced glutathione (GSH) and protein contents, antioxidant enzymes (SOD, CAT, GPx, GR, GST), phosphatases (ALP, AcP) and aminotransferases (AST, ALT) activities were significantly reduced. Additionally, considerable amendments in hormonal levels (testosterone, luteinizing and follicle-stimulating hormone) and sperm characteristics were spotted. Further, histological variations in the testes section were detected and this supports the biochemical observations. Otherwise, rats supplemented with bromelain alone diminished TBARS and H2O2 and augmented mostly other parameters. Furthermore, supplementation with bromelain before Al intoxication in rats exhibited worthy betterment in oxidative stress markers, hormones, and sperm quality compared to Al treated group. CONCLUSION: In conclusion, bromelain had a powerful protective role against Al-induced testicular dysfunction so, it represents a novel approach in metal toxicity processing.


Assuntos
Ananas/química , Bromelaínas/química , Bromelaínas/farmacologia , Cloreto de Alumínio/química , Animais , Antioxidantes/química , Glutationa/química , Hormônios/metabolismo , Peróxido de Hidrogênio/química , Masculino , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Wistar
10.
Sci Rep ; 10(1): 2698, 2020 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-32060369

RESUMO

The knowledge about a potential in vivo uptake and subsequent toxicological effects of aluminum (Al), especially in the nanoparticulate form, is still limited. This paper focuses on a three day oral gavage study with three different Al species in Sprague Dawley rats. The Al amount was investigated in major organs in order to determine the oral bioavailability and distribution. Al-containing nanoparticles (NMs composed of Al0 and aluminum oxide (Al2O3)) were administered at three different concentrations and soluble aluminum chloride (AlCl3·6H2O) was used as a reference control at one concentration. A microwave assisted acid digestion approach followed by inductively coupled plasma mass spectrometry (ICP-MS) analysis was developed to analyse the Al burden of individual organs. Special attention was paid on how the sample matrix affected the calibration procedure. After 3 days exposure, AlCl3·6H2O treated animals showed high Al levels in liver and intestine, while upon treatment with Al0 NMs significant amounts of Al were detected only in the latter. In contrast, following Al2O3 NMs treatment, Al was detected in all investigated organs with particular high concentrations in the spleen. A rapid absorption and systemic distribution of all three Al forms tested were found after 3-day oral exposure. The identified differences between Al0 and Al2O3 NMs point out that both, particle shape and surface composition could be key factors for Al biodistribution and accumulation.


Assuntos
Alumínio/farmacologia , Disponibilidade Biológica , Nanoestruturas/química , Distribuição Tecidual/efeitos dos fármacos , Administração Oral , Alumínio/química , Cloreto de Alumínio/química , Cloreto de Alumínio/farmacologia , Óxido de Alumínio/química , Óxido de Alumínio/farmacologia , Animais , Humanos , Intestinos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Baço/efeitos dos fármacos
11.
Molecules ; 25(3)2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31979084

RESUMO

Based on a foregoing gram-scale laboratory process, an efficient scale-up preparation process of 5,2'-dibromo-2,4',5'-trihydroxydiphenylmethanone (LM49-API), a new acute pyelonephritis candidate drug, was developed and validated aiming to reduce by-products and achieve better impurity profiles. Meanwhile, the polymorph of LM49-API and process-related impurities were also investigated. Ultimately, the optimal reaction conditions were verified by evaluating the impurity profiles and their formation during the synthesis. Six process-related impurities were synthesized and identified, being useful for the quality control of LM49-API. Its finalized preparation process was further validated at 329-410 g scale-up production in 53.4-57.1% overall yield with 99.95-99.98% high-performance liquid chromatography (HPLC) purity, and it is currently viable for commercial production. LM49-API-imC and LM49-API-imX were identified as the main single impurities in LM49-API, with the content controlled to be less than 0.03%.


Assuntos
Antifúngicos/uso terapêutico , Pielonefrite/microbiologia , Cloreto de Alumínio/química , Animais , Cromatografia Líquida de Alta Pressão
12.
Artigo em Inglês | MEDLINE | ID: mdl-31846384

RESUMO

A combination of electrocoagulation and coagulation-flocculation processes was used for re-refining effluent from lubricating oils. The efficiency of the process was evaluated based on the chemical oxygen demand (COD), color, and turbidity of the refined effluent. Electrocoagulation (EC) and coagulation-flocculation parameters, such as the initial pH (3.00, 4.41, and 9.00), and current density (4, 9, and 16 A/m2), and the use of aluminum polychloride coagulant and superfloc A300 flocculant were studied. EC performed at pH 9, with a current density of 16 A/m2 and 7 V, resulted in removal efficiencies of 85.14%, 99.81%, and 99.85%, for COD, color, and turbidity, respectively. The removal efficiencies increased to 96%, 99.87%, and 99.94% for COD, color, and turbidity, respectively, by the further coagulation-flocculation treatment in the presence of 13.8 mg/L aluminum polychloride coagulant and 80 mg/L Superfloc A300 flocculant.


Assuntos
Técnicas Eletroquímicas/métodos , Floculação , Resíduos Industriais/análise , Óleo Mineral/química , Eliminação de Resíduos Líquidos/métodos , Cloreto de Alumínio/química , Análise da Demanda Biológica de Oxigênio
13.
Environ Sci Pollut Res Int ; 26(31): 32189-32197, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31494850

RESUMO

The present study evaluated the possible ameliorative efficacy of selenium nanoparticles (SeNPs) on AlCl3-induced hepatorenal injury in rats. Animals were randomly divided into four groups (n = 6): group 1, the control; group 2, received SeNPs (0.4 mg/kg b.wt) for 21 days; group 3, injected with three doses of AlCl3 intraperitoneally (30 mg/kg/body weight) every 5 days; group 4, received SeNPs for 7 days prior to AlCl3 and then received SeNPs concurrently with AlCl3 for the following 14 days. It was observed that AlCl3 increased the levels of AST, ALT, ALP, LDH, total bilirubin, creatinine, urea, uric acid, and MDA significantly; as well as the reduction in the levels of GSH, SOD, GPx stores in comparison with the control group. These biochemical alterations were accompanied and confirmed by the lesion appeared in histological sections in addition to the increase in the expression of caspase-3 and the decrease of the Bcl-2expression. Treatment with SeNPs ameliorates the hepatorenal dysfunction, replenishes the endogenous antioxidant system, downregulates the expression of caspase-3, and upregulates the expression of Bcl-2. This hepatorenal ameliorative role may be due to the ability of SeNPs to equilibrate the oxidant/antioxidant system besides its ability to attenuate apoptosis process.


Assuntos
Cloreto de Alumínio/metabolismo , Antioxidantes/química , Apoptose/efeitos dos fármacos , Creatinina/metabolismo , Nanopartículas/química , Estresse Oxidativo/efeitos dos fármacos , Selênio/metabolismo , Cloreto de Alumínio/química , Animais , Antioxidantes/metabolismo , Creatinina/química , Fígado/efeitos dos fármacos , Masculino , Ratos , Selênio/química
14.
Eur J Pharm Sci ; 139: 105056, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31446076

RESUMO

Topical application of aluminum-chloride phthalocyanine (AlClPc) is a challenge because of the drug's extremely low solubility, which prevents its absorption into deeper skin layers and causes molecule aggregation, reducing the photophysical effect. The goal of this study was to obtain a formulation applied in a certain condition that would allow homogeneous accumulation of AlClPc in cutaneous tissues, meaning a safer and non-invasive topical treatment for skin tumors based on photodynamic therapy. We first prepared and characterized AlClPc complexes with cyclodextrin to increase the photosensitizing agent solubility. The inclusion complex of AlClPc with hydroxypropyl-ß-cyclodextrin (HP-ßCD) amplified its loading dose in aqueous medium and maintained its photosensitizing properties in terms of reactive oxygen species production. Assays to determine the complex's in vitro cytotoxicity against murine melanoma skin cancer cells showed that when irradiated, the complex significantly reduced cell viability, whereas the absence of irradiation did not affect cell viability. Three physical techniques for permeation enhancement (i.e., tape-stripping abrasion, microneedle pretreatment and iontophoresis) were then evaluated. When applied in impaired skin, the complex could not increase drug penetration. The skin penetration of AlClPc, however, increased 2.3-fold following iontophoresis application in a shorter period compared to passive permeation. Therefore, these results suggest the administration of complexed AlClPc mediated by iontophoresis, followed by application of photodynamic therapy, might be an effective and non-invasive alternative for topical treatment of cutaneous tumors.


Assuntos
2-Hidroxipropil-beta-Ciclodextrina/administração & dosagem , Cloreto de Alumínio/administração & dosagem , Indóis/administração & dosagem , Melanoma Experimental/tratamento farmacológico , Compostos Organometálicos/administração & dosagem , Fármacos Fotossensibilizantes/administração & dosagem , Neoplasias Cutâneas/tratamento farmacológico , 2-Hidroxipropil-beta-Ciclodextrina/química , Administração Cutânea , Cloreto de Alumínio/química , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Indóis/química , Iontoforese , Camundongos , Compostos Organometálicos/química , Fotoquimioterapia , Fármacos Fotossensibilizantes/química , Espécies Reativas de Oxigênio/química , Pele/metabolismo , Absorção Cutânea , Suínos
15.
Food Res Int ; 122: 419-431, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31229096

RESUMO

Potato flakes (PFs) are made by boiling, mashing and subsequent drying of steam peeled potatoes. Their cold-water swelling starch readily develops viscosity upon hydration. That potato starch amylopectin (AP) contains esterified phosphate groups results in rapid swelling and high viscosity of PF suspensions. This study is the first report on the impact of sodium, calcium and aluminum chloride on (i) the physicochemical properties of PFs and (ii) the water dynamics in relation to oil uptake in the production of deep-fried crisps made thereof. Adding 125 µmol cation/g PF dry matter (dm) of these salts to PF suspensions (8.0% dm) in a Rapid Visco Analyzer (RVA) decreased the peak viscosities by 5% (sodium chloride) and 20% (calcium or aluminum chloride). While monovalent cations shield the negative charges of the phosphate monoesters on the starch chains, divalent and trivalent cations bridge phosphate groups of adjacent AP molecules and thereby reduce swelling even further. Moreover, the latter ions result in up to 20% higher RVA cold paste viscosity readings even if they do not affect amylose (AM) aggregation. They thus enhance the gelation of PFs by AP bridging. For producing deep-fried crisps, PFs, emulsifier and maltodextrin were hydrated, mixed, sheeted into dough, and deep-fried. Including the above dosage of calcium ions in its recipe increased the specific strength of the dough sheet by about 15%. Time domain proton nuclear magnetic resonance analysis of dough sheets showed that these ions increase the rigidity of the starchy gel network while AM crystallization remains largely unaffected. This is evidence that ionic cross-linking of AP directly strengthens the dough sheet. Moreover, the calcium ions lowered the lipid content of the deep-fried crisps by about 5% due to stronger interaction of starch polymers with water. Ionic cross-linking of AP thus improves the gel forming capacity of PFs and strengthens the starchy gel network during manufacturing of potato-based snacks resulting in crisps with a significantly lower lipid content.


Assuntos
Manipulação de Alimentos , Géis/química , Solanum tuberosum/química , Amido/química , Água/química , Cloreto de Alumínio/química , Amilopectina/química , Cálcio/química , Fenômenos Químicos , Emulsificantes/química , Íons/química , Minerais/química , Fosfatos/química , Proteólise , Lanches , Sódio/química , Viscosidade
16.
Sci Total Environ ; 685: 74-84, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31174125

RESUMO

As widely used Al-based coagulants, poly aluminum chloride (PAC) and aluminum sulfate (AS) were adopted in a short term at the start-up stage (from 10th to 16th) to enhance the formation of aerobic granules, and their effects on aerobic granulation were elucidated. The results suggested that both PAC and AS facilitated the granulation by improving the physicochemical properties of sludge. The reactor performance in pollutant removal was also enhanced. Specifically, in terms of extracellular polymeric substances (EPS), PAC dosing mainly stimulated the production of loosely bound EPS (LB-EPS), whereas more tightly bound EPS (TB-EPS) were secreted with the presence of AS. Based on the elemental analysis, polymeric Al hydrolyzed from PAC mainly worked on the exterior of microbial aggregates, and thus the attached aluminum in granules was gradually eliminated by ion exchange and hydraulic shear force. In contrast, the aluminum species in AS hydrolyzed into monomeric and oligomeric Al, and thus could diffuse into the interior of microbial aggregates and eventually created an "Al-core" in the granules. Overall, the present study describes the AGS formation with Al-based coagulants and the mechanisms of PAC- and AS-enhanced aerobic granulation.


Assuntos
Cloreto de Alumínio/química , Alumínio/química , Eliminação de Resíduos Líquidos/métodos , Compostos de Alúmen
17.
Chemosphere ; 229: 262-272, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31078883

RESUMO

Because of the influence of hydrolysed species from Al-based coagulants on coagulation performance, the performance and mechanism of the developed hybrid ozonation-coagulation (HOC) process using AlCl3·6H2O and preformed Al13 as coagulants were investigated in this study, in which ozonation and coagulation occurred simultaneously within a single unit. It was found that the HOC process exhibited higher organic matter removal performance compared with coagulation and the pre-ozonation-coagulation process. It was found that the high ibuprofen (IBP) removal efficiency in the HOC process was mainly attributed to OH oxidation promoted by in situ formed hydrolysed aluminium species from AlCl3·6H2O and preformed Al13. Furthermore, the surface hydroxyl groups were determined to be the active reaction sites for the HOC process. Due to the higher proportion of surface hydroxyl groups for Al13, the HOC process with preformed Al13 as coagulants (Al13-HOC) exhibited a higher removal performance than that with AlCl3·6H2O as the coagulant (AlCl3-HOC). It was revealed that most of the generated O2- in the Al13-HOC was adsorbed on the surface of Al13 at different pH values, while a considerably lower proportion of adsorbed O2- was observed on the surface of in situ formed Al species from AlCl3·6H2O. Nevertheless, low proportions of adsorbed OH were found on the surfaces of both preformed Al13 and in situ formed Al species, indicating that the OH oxidation for the removal of organic pollutants occurred primarily in the aqueous phase.


Assuntos
Alumínio/química , Ozônio/química , Adsorção , Cloreto de Alumínio/química , Hidrólise , Ibuprofeno/química , Ibuprofeno/isolamento & purificação , Purificação da Água
18.
Int J Mol Sci ; 20(8)2019 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-31014012

RESUMO

Alzheimer's disease (AD) is a progressive neurodegenerative disorder more prevalent among the elderly population. AD is characterised clinically by a progressive decline in cognitive functions and pathologically by the presence of neurofibrillary tangles (NFTs), deposition of beta-amyloid (Aß) plaque and synaptic dysfunction in the brain. Centella asiatica (CA) is a valuable herb being used widely in African, Ayurvedic, and Chinese traditional medicine to reverse cognitive impairment and to enhance cognitive functions. This study aimed to evaluate the effectiveness of CA in preventing d-galactose/aluminium chloride (d-gal/AlCl3) induced AD-like pathologies and the underlying mechanisms of action were further investigated for the first time. Results showed that co-administration of CA to d-gal/AlCl3 induced AD-like rat models significantly increased the levels of protein phosphatase 2 (PP2A) and decreased the levels of glycogen synthase kinase-3 beta (GSK-3ß). It was further observed that, CA increased the expression of mRNA of Bcl-2, while there was minimal effect on the expression of caspase 3 mRNA. The results also showed that, CA prevented morphological aberrations in the connus ammonis 3 (CA 3) sub-region of the rat's hippocampus. The results clearly demonstrated for the first time that CA could alleviate d-gal/AlCl3 induced AD-like pathologies in rats via inhibition of hyperphosphorylated tau (P-tau) bio-synthetic proteins, anti-apoptosis and maintenance of cytoarchitecture.


Assuntos
Doença de Alzheimer/prevenção & controle , Centella/química , Hipocampo/metabolismo , Transdução de Sinais/efeitos dos fármacos , Triterpenos/farmacologia , Cloreto de Alumínio/química , Cloreto de Alumínio/toxicidade , Doença de Alzheimer/etiologia , Doença de Alzheimer/veterinária , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Centella/metabolismo , Galactose/química , Galactose/toxicidade , Glicogênio Sintase Quinase 3 beta/metabolismo , Hipocampo/efeitos dos fármacos , Masculino , Extratos Vegetais , Proteína Fosfatase 2/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos , Ratos Wistar , Triterpenos/química , Triterpenos/uso terapêutico
19.
Bioresour Technol ; 284: 98-104, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30927653

RESUMO

Rice straw was pretreated with ethylene glycol (EG) and AlCl3 for enzymatic hydrolysis. EG-AlCl3 pretreatment had an extremely good selectivity for component fractionation, resulting in 88% delignification and 90% hemicellulose removal, with 100% cellulose recovered or 76% (w/w) cellulose content in solid residue at 150 °C with 0.055 mol/L AlCl3. The pretreated residue (5%, w/v) presented a higher enzymatic hydrolysis rate (glucose yield increased 2 times to 94%) for 24 h at cellulase loading of 10 FPU/g. The hydrolysis behavior was correlated with the composition and structure of substrates characterized by SEM, FT-IR, BET, XRD and TGA. The enzyme adsorption ability of pretreated straw was 12-folds that for the original sample. EG-AlCl3 solution was further cycled for 3 times with 100% cellulose recovery but only 29% lignin removal due to the loss of AlCl3. EG-AlCl3 pretreatment is an efficient method with little loss of cellulose for lignocelluloses.


Assuntos
Cloreto de Alumínio/química , Celulase/metabolismo , Celulose/isolamento & purificação , Etilenoglicol/química , Oryza/química , Celulose/química , Celulose/metabolismo , Hidrólise , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Polissacarídeos/metabolismo
20.
Biomacromolecules ; 20(5): 2123-2134, 2019 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-30908911

RESUMO

The evolution of interactions in the bovine serum albumin (BSA) protein solution on addition of mono and multivalent (di, tri and tetra) counterions has been studied using small-angle neutron scattering (SANS), dynamic light scattering (DLS) and ζ-potential measurements. It is found that in the presence of mono and divalent counterions, protein behavior can be well explained by DLVO theory, combining the contributions of screened Coulomb repulsion with the van der Waals attraction. The addition of mono or divalent salts in protein solution reduces the repulsive barrier and hence the overall interaction becomes attractive, but the system remains in one-phase for the entire concentration range of the salts, added in the system. However, contrary to DLVO theory, the protein solution undergoes a reentrant phase transition from one-phase to a two-phase system and then back to the one-phase system in the presence of tri and tetravalent counterions. The results show that tri and tetravalent (unlike mono and divalent) counterions induce short-range attraction between the protein molecules, leading to the transformation from one-phase to two-phase system. The two-phase is characterized by the fractal structure of protein aggregates. The excess condensation of these higher-valent counterions in the double layer around the BSA causes the reversal of charge of the protein molecules resulting into reentrant of the one-phase, at higher salt concentrations. The complete phase behavior with mono and multivalent ions has been explained in terms of the interplay of electrostatic repulsion and ion-induced short-range attraction between the protein molecules.


Assuntos
Soroalbumina Bovina/química , Cloreto de Alumínio/química , Cloretos/química , Difusão Dinâmica da Luz , Cloreto de Magnésio/química , Difração de Nêutrons , Concentração Osmolar , Conformação Proteica , Espalhamento a Baixo Ângulo , Eletricidade Estática , Zircônio/química
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