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1.
Int J Biol Macromol ; 255: 128007, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37977461

RESUMO

Water is a vital component of life; therefore, it is critical to have access to pure water for various life-sustaining activities including agriculture and human consumption. An eco-friendly nanocomposite based on chitosan (Cs) and nanomaterials (CaCO3-NPs) were combined to amalgamate the advantages of biopolymers and nanomaterials to overcome the problems of instability, poor mechanical properties, and low removal percentage of biopolymers. The as-prepared samples were characterized and were used for the removal of heavy metal from wastewater. X-ray diffractometer, Fourier transform infrared spectroscopy, and transmission electron microscope were used to distinguish the prepared absorbents. The absorption of the heavy metals by as-prepared samples was examined at different conditions. The kinetic and isotherm models of the adsorption process were also studied. The data showed that the removal percentages of Cd, Cu, Pb, Zn, Cr and Ni by the composite were 98.0, 94.8, 99.0, 97.9, 97.4 and 98.3 %, respectively. The kinetic and isothermal studies showed that the absorption of these metal ions by the samples obeyed a pseudo-second-order mechanism and Langmuir isotherm model, respectively. In addition, the maximum adsorption capacities of Cd, Cu, Pb, Zn, Cr, and Ni ions by as-prepared nanocomposite were 83.33, 47.84, 98.03, 89.28, 62.11, and 63.69 mg/g, respectively.


Assuntos
Quitosana , Metais Pesados , Nanocompostos , Nanopartículas , Poluentes Químicos da Água , Humanos , Quitosana/química , Cádmio/química , Chumbo , Metais Pesados/química , Biopolímeros/química , Adsorção , Nanopartículas/química , Íons , Água/química , Poluentes Químicos da Água/química , Cinética , Concentração de Íons de Hidrogênio
2.
Int J Biol Macromol ; 257(Pt 2): 128711, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38096929

RESUMO

The green microalga Scenedesmus obliquus, isolated from the Egyptian environment, was used for the synthesis of bio-based plastic materials. Polyurethane (PU) was blended with different proportions (0%, 10%, 20%, and 40%) of chloroform extract to form bioplastic films. The bioplastic films were characterized using water vapor transmission rate measurements and scanning electron microscopy (SEM). The WVTR of pure PU was 193.37 g/m2. day, while the values of algae/PU films were 129.74, 122.56, and 99.75 g/m2.day. S. obliquus reported having Palmitic, which possesses antimicrobial activity and acts as an effective antimicrobial agent in the synthesized bioplastic films. Antimicrobial activity of the algal extract and the synthesized bioplastic films were tested against two Gram-positive bacteria; Staphylococcus aureus, Enterococcus faecalis, two Gram-negative bacteria; Escherichia coli, Pseudomonas aeruginosa, and Candida albicans as a model for fungi. The results indicated that S. obliquus extract exhibited a clear antimicrobial activity against all tested microbes. The antimicrobial rate of bioplastic films containing 40% of the extract reached 100% after 2 h of contact with E. coli and E. faecalis. In conclusion, this study offers a promising future for the use of biodegradable antimicrobial bioplastic films as an affordable and environmentally friendly alternative to plastics in many applications.


Assuntos
Anti-Infecciosos , Microalgas , Scenedesmus , Poliuretanos , Escherichia coli , Anti-Infecciosos/farmacologia , Candida albicans , Biopolímeros
3.
Carbohydr Polym ; 305: 120571, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36737211

RESUMO

Wastewater rich in heavy metals and organic compounds represents one of the essential environmental pollutants. Therefore, a practical approach is to fabricate eco-friendly polymer-based systems with a high ability to absorb pollutants. Herein, bionanocomposites consisting of chitosan (Cs) grafted by various monomers, such as acrylamide (Am), acrylic acid (AA), and 4-styrene sulfonic acid (SSA), and hybrid nanoparticles of graphene oxide/titanium dioxide nanoparticles (GO@TiO2-NPs) were fabricated. The prepared nanomaterials and bionanocomposites characterized via various tools. The data illustrated that the prepared GO had a thickness of 10 nm and TiO2-NPs had a diameter of 25 nm. In addition, the grafted chitosan (gCs) using Am and SSA had the largest surface area (gCs2; 22.89 nm) and its bionanocomposite (NC5; 104.79 nm). In addition, the sorption ability of the 0.15 g of prepared bionanocomposites to the (100 mg/L) of lead ions (Pb2+) and (25 mg/L) of basic-red 46 (BR46) under various conditions has been studied. The results showed that gCs3 and NC5 had the highest adsorption of Pb2+ (79.54 %) and BR46 (79.98 %), respectively. The kinetic study results of the sorbents obeyed the Pseudo second-order model. In contrast, the isothermal study followed the Freundlich adsorption model for Pb2+ and the Langmuir adsorption model for BR46.

4.
Eur Rev Med Pharmacol Sci ; 26(23): 8738-8755, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36524493

RESUMO

OBJECTIVE: Despite its evident renal toxicity, vancomycin is considered an effective glycopeptide antibiotic against life-threatening positive bacterial contagions. The current study aimed to investigate the potential protective effects of carvacrol as well as its underlying mechanism against vancomycin-induced nephrotoxicity. MATERIALS AND METHODS: The animals were randomly classified into four groups (8 rats per group). Group I, which served as a control group, received only vehicles. Group II received a single i.p. injection of 50 mg/kg of carvacrol for seven days. Group III received vancomycin (200 mg/kg, i.p.) as a singular daily dose for seven days. Carvacrol was administered to Group IV seven days prior to the daily vancomycin dose. RESULTS: The results revealed that carvacrol minimized vancomycin-induced renal injury as evidenced by lower serum cystatin C levels and kidney injury molecule-1 (KIM-1), in addition to a decline in renal damage caused by vancomycin as indicated in histopathological assessment. Furthermore, carvacrol significantly attenuated oxidative stress parameters and inflammatory mediators. Moreover, it downregulated Keap1, mitogen-activated protein kinase (p38MAPK), and nuclear factor kappa B (NF-κB) genes and proteins, along with controlling the NF-κB inhibitory protein (IkBα) and nuclear factor erythroid 2-related factor 2 (Nrf2) genes and proteins observed through streaming its genes. A molecular docking technique was also used to investigate the potential interactivity between carvacrol and proteins involved in regulating oxidative injury and inflammatory responses. CONCLUSIONS: The current study findings revealed that carvacrol administration before vancomycin could be a promising therapeutic approach for maceration of renal damage stimulated by vancomycin via controlling IkBα/MAPK and Keap1/Nrf2 signaling molecules.https://www.europeanreview.org/wp/wp-content/uploads/graphical-abstract-1.jpg.


Assuntos
Fator 2 Relacionado a NF-E2 , Proteínas Quinases p38 Ativadas por Mitógeno , Animais , Ratos , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Rim/patologia , Simulação de Acoplamento Molecular , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , Estresse Oxidativo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Transdução de Sinais , Vancomicina/toxicidade
5.
Eur Rev Med Pharmacol Sci ; 26(24): 9393-9408, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36591848

RESUMO

OBJECTIVE: Among other types of cancerous lesions, lung cancer is one of the prevalent causes of death. Trigonelline is a plant alkaloid, a significant constituent in coffee, and has shown health benefits in several disorders. The present study aims to investigate the potential therapeutic role of trigonelline in lung cancer. MATERIALS AND METHODS: Seventy-five BALB/C mice were assigned to five groups and treated for 150 days as follows (1): normal control group; (2) trigonelline only (50 mg/kg/ P.O) daily for the last thirty days; (3) urethane (1.5 g/kg B.w/i.p) at day one and sixty; (4) urethane and carboplatin (15 mg/kg i.p) for the last thirty days; and (5) urethane and trigonelline for the last thirty days. Tumor size was measured while blood and lung were collected for biochemical, western blotting analysis, and histological examinations. RESULTS: Urethane demonstrated significant changes in all biochemical and molecular parameters and histological examinations. In animals pretreated with urethane, trigonelline significantly reduced tumor size and restored Nrf2, NF-кB p65, Bcl-2, Cyclin D1, ICAM-1, and MMP-2, along with improving cGMP and active caspase three and refining histological architectures. CONCLUSIONS: Nrf2 signaling may be a promising therapeutic target for adenocarcinoma protection or management. Due to its multiple therapeutic effects on Nrf2, cyclin D1, NF-кB pathways, and the BAX/Bcl2 axis, trigonelline significantly induced cell cycle arrest and apoptosis.https://www.europeanreview.org/wp/wp-content/uploads/Graphical_Abstract-1.jpg.


Assuntos
Alcaloides , Neoplasias Pulmonares , Camundongos , Animais , Uretana/efeitos adversos , NF-kappa B , Caspases , Ciclina D1 , Fator 2 Relacionado a NF-E2 , Camundongos Endogâmicos BALB C , Neoplasias Pulmonares/induzido quimicamente , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Alcaloides/efeitos adversos , Inibidores Enzimáticos , Apoptose
6.
Int J Biol Macromol ; 167: 1435-1444, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33202266

RESUMO

The current work focuses on a cheap and simple preparation of highly conducting chitosan/hydroxyl ethylcellulose/polyaniline loaded with graphene oxide doped by silver nanoparticles (CS/HEC/PAni/GO@Ag) bionanocomposite as a biodegradable and biocompatible hydrogel for energy storage technology. Scanning electron microscopy (SEM) displays the compatibility of chitosan, hydroxyl ethyl cellulose, and polyaniline and a good distribution of GO@Ag-NPs in bionanocomposite hydrogels. X-ray diffraction (XRD) displayed the structure and existence of GO@Ag-NPs in the matrix. The swelling percentage and the antibacterial activities slightly increased with raising the content of GO@Ag-NPs. Also, the presence of both chitosan and cellulose improves the biodegradation of the fabricated bionanocomposites, which is increased by adding GO. Moreover, the incorporation of 5% GO@Ag-NPs in hydrogels enhances dc-conductivity by about 25 times from 3.37 × 10-3 to 8.53 × 10-2 S/cm. The fabricated hydrogels are inexpensive, eco-friendly, and have high capacitance and permittivity, and so they can store electrical energy.


Assuntos
Celulose/análogos & derivados , Quitosana/química , Grafite/química , Hidrogéis/química , Nanopartículas Metálicas/química , Nanocompostos/química , Prata/química , Anti-Infecciosos/química , Bacillus subtilis/efeitos dos fármacos , Biodegradação Ambiental , Candida albicans/efeitos dos fármacos , Celulose/química , Condutividade Elétrica , Escherichia coli/efeitos dos fármacos , Nanopartículas Metálicas/ultraestrutura , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Nanocompostos/ultraestrutura , Espectroscopia de Infravermelho com Transformada de Fourier , Staphylococcus aureus/efeitos dos fármacos , Difração de Raios X
7.
Int J Biol Macromol ; 140: 886-894, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31449867

RESUMO

The chitosan/polyacrylic acid/polypyrrole/loaded with silver nanoparticles (CS/PAA/PPy/Ag-NPs) bionanocomposite as conductive, biodegradable, and biocompatible hydrogels were prepared by the casting method. Silver nanoparticles (Ag-NPs) were incorporated into the prepared bionanocomposite hydrogels to reinforce the electrical conductivity as well as the antimicrobial properties of the prepared hydrogels. The scanning electron microscopy revealed the compatibility of chitosan, polyacrylic acid, and polypyrrole, as well as Ag-NPs, were inserted in the polymer matrix and dispersed well on the superficies of the prepared bionanocomposites. X-ray diffraction displayed the presence of Ag-NPs into the polymer matrix. Also, the appearance of characteristic peaks in the Fourier transform infrared confirmed the compatibility of three polymers. Additionally, the swelling properties, antimicrobial activity as well as the electrical and dielectric characteristics of the fabricated bionanocomposites hydrogels were investigated. Moreover, the DC-conductivity was studied and our data designated that the DC-conductivity of the prepared bio-nanocomposites was improved by the existence of PPy more precisely than that of Ag-NPs. However, both were of high conductivity compared to that of the CS/PAA and found to follow the BNN universal relation. Also, The activation energy of about 55 kJ/mol of CS:2PAA hydrogel and reduce to about 15 kJ/mol in all the considered bionanocomposites after addition of Ag-NPs. Furthermore, the antibacterial activities of the knowledgeable microbes were improved as a result of the presence of Ag-NPs in bionanocomposites hydrogels.


Assuntos
Materiais Biocompatíveis/química , Quitosana/química , Condutividade Elétrica , Hidrogéis/química , Nanocompostos/química , Prata/química , Resinas Acrílicas/química , Antibacterianos/química , Antibacterianos/farmacologia , Materiais Biocompatíveis/farmacologia , Nanocompostos/ultraestrutura , Espectroscopia de Infravermelho com Transformada de Fourier
8.
Heliyon ; 5(3): e01332, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30923764

RESUMO

Lignocellulosic fibers, which obtained from Citrus trees trimmings, were modified with Aspergillus flavus (EGYPTA5) enzymes. The non-modified and the modified lignocellulosic fibers were used with low density polyethylene (LDPE) by melt blending brabender method at 170 °C with different ratio (5, 10 and 20 wt%) to obtain wood plastic composites (WPC). The prepared samples were characterized using Fourier-transformed infrared (FT-IR), Scan Electron Microscope (SEM), and Water vapor transmission rate (WVTR) as well as, the mechanical, thermal, biodegradability and swelling properties were examined. The fabricated WPC displayed good mechanical and thermal properties compare with pure LDPE. Also, the WVTR was enhanced by the addition of modified lignocellulosic fibers over the unmodified one. Moreover, the enzymes assay such as cellulase and lignin peroxidase enzymes were estimated and confirming the growing of fungi on the lignocellulosic fiber in solid state fermentation condition to improve lignin peroxidase production and eliminate cellulose enzymes. The fabricated WPC can be used in different environmental application such as packaging system, that it will be green, economic, and partially biodegradable.

9.
Int J Biol Macromol ; 123: 856-865, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30452990

RESUMO

Chitosan nanoparticles (CS-NPs) and chitosan/polyacrylic acid hydrogel nanoparticles (CS/PAA-HNPs) were obtained by ionic gelation with tripolyphosphate anions and copolymerization of CS with acrylic acid (AA), respectively. The prepared NPs were loaded by different concentrations of copper (1, 2 and 3% with respect to CS) to obtain chitosan/copper nanocomposites (CS/Cu-NCs) and chitosan/polyacrylic acid/copper hydrogel nanocomposites (CS/PAA/Cu-HNCs). The prepared NPs and their NCs were characterized by different techniques. The swelling properties and copper release from CS/Cu-NCs and CS/PAA/Cu-HNCs were evaluated. The antibacterial activity of the prepared samples against bacteria (e.g., Staphylococcus aureus and Pseudomonas aeruginosa), fungi, and yeast were investigated. The results displayed that the copper release, as well as the swelling percentage of CS/PAA/Cu-HNCs, were higher than that of CS/Cu-NCs. Furthermore, the impact of using CuSO4, CS/Cu-NCs, and CS/PAA/Cu-HNCs as a different source of copper on chlorophyll content, vegetative growth, minerals content, and the yield of onion plants during two seasons 2016 and 2017 were studied. It was found that the yield, plant growth, and nutrient content of onion bulbs were improved using CS/PAA-HNPs, which was loaded with 75 ppm copper, as foliar spray for onion plants.


Assuntos
Resinas Acrílicas/farmacologia , Quitosana/farmacologia , Cobre/farmacologia , Nanocompostos/química , Cebolas/crescimento & desenvolvimento , Resinas Acrílicas/síntese química , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Varredura Diferencial de Calorimetria , Quitosana/síntese química , Fungos/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Nanocompostos/ultraestrutura , Cebolas/efeitos dos fármacos , Tamanho da Partícula , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Termogravimetria
10.
Carbohydr Polym ; 196: 483-493, 2018 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-29891322

RESUMO

Bionanocomposites hydrogel based on conducting polymers were successfully fabricated from chitosan/polyacrylic acid/polypyrrole (CS/PAA/PPy) as well as the magnetite nanoparticle (Fe3O4-NPs) was prepared via co-precipitation method. In addition, different ratios of Fe3O4-NPs were added to the prepared bionanocomposites to enhance the antimicrobial and the electrical conductivity of the prepared conductive hydrogel. Furthermore, the morphology, the swelling percent, antimicrobial activity and the dielectric properties of the prepared conducting bionanocomposites hydrogel were investigated. The antibacterial activities of the experienced microbes were improved with the increasing the loading of Fe3O4-NPs in conducting Bio-nanocomposites hydrogel. Moreover, the DC-conductivity was examined and our resulted indicated that the DC-conductivity was enhanced by increasing the loadings of Fe3O4-NPs compared to that of the pure CS/PAA as well as CS/PAA/PPy.


Assuntos
Resinas Acrílicas/química , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Quitosana/química , Hidrogéis/química , Nanopartículas de Magnetita/química , Nanocompostos/química , Polímeros/química , Pirróis/química , Candida albicans/efeitos dos fármacos , Impedância Elétrica , Pseudomonas aeruginosa/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos
11.
J Neonatal Perinatal Med ; 10(1): 79-83, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28304322

RESUMO

OBJECTIVE: We aimed to investigate if endothelin 1 concentration at day 3 postnatal age could be used as a predictive marker for development of bronchopulmonary dysplasia in preterm neonates with respiratory distress syndrome. METHODS: This prospective observational study was done on 69 preterm neonates with gestational ages between 28 and 34 weeks and diagnosed as having respiratory distress syndrome. Serum concentrations of endothelin 1 was measured for all patients at day 3 of life and they were divided into BPD and No-BPD groups according to whether they developed bronchopulmonary dysplasia or not. RESULTS: A total of 17 infants were in the BPD group and 52 infants were in the No-BPD group. Serum endothelin 1 was significantly higher in the BPD group (435.39±172.88) compared with the No-BPD group (302.65±49.32) (p < 0.001). Serum endothelin 1 correlated significantly with days spent on mechanical ventilation (r = 0.379, p = 0.022) and days spent on CPAP (r = 0.391, p = 0.001). A serum endothelin 1 cut off value of 302.7 ng/L could predict preterm that will develop bronchopulmonary dysplasia with a sensitivity of 88.24%, and specificity of 61.54%. CONCLUSION: Serum endothelin 1 is significantly increased at day 3 of life in preterm neonates with respiratory distress syndrome who later develop bronchopulmonary dysplasia (BPD). It seems to be a promising predictive marker for BPD but further studies are needed to find the appropriate time for its measurement.


Assuntos
Displasia Broncopulmonar/sangue , Endotelina-1/sangue , Síndrome do Desconforto Respiratório do Recém-Nascido/sangue , Biomarcadores/sangue , Displasia Broncopulmonar/epidemiologia , Técnicas de Apoio para a Decisão , Ensaio de Imunoadsorção Enzimática , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Masculino , Estudos Prospectivos , Índice de Gravidade de Doença
12.
Carbohydr Polym ; 147: 333-343, 2016 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-27178939

RESUMO

Polyaniline (PANI) with/without polystyrene (PS), was successfully manufactured in the occurrence of dispersed pulp fibers via the oxidative polymerization reaction of aniline monomer to produce conductive paper sheets containing PANI, PANI/PS composites. Additionally, sliver nitrate (Ag-NO3) was added by varied loadings to the oxidative polymerization of aniline monomer to provide sliver nanoparticles (Ag-NPs) emptied into the prepared paper sheets. The prepared paper sheets were examined using scanning electron microscopy (SEM), X-ray diffraction (XRD) and infrared spectroscopy (IR), the mechanical properties of the prepared paper sheets were evaluated. Moreover, the electrical conductivity and biological studies such as cellulases assay, Microorganism & culture condition and detection of the released of Ag-NPs were evaluated. Furthermore, the prepared paper sheets were displayed good antibacterial properties contrary to gram positive and gram negative bacteria. Consequently, the prepared paper sheet may be used as novel materials for packaging applications.


Assuntos
Compostos de Anilina/química , Condutividade Elétrica , Nanocompostos/química , Nanopartículas/química , Papel , Poliestirenos/química , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Microscopia Eletrônica de Varredura , Nanocompostos/microbiologia , Nanocompostos/ultraestrutura , Prata/química , Difração de Raios X
13.
Eur J Pain ; 20(4): 639-51, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26392220

RESUMO

BACKGROUND: Pain catastrophizing significantly affects an individual's experience of pain. High pain catastrophizing is associated with increased fear avoidance behaviours, pain intensity and disability. The aim of this investigation was to determine the effect of pain catastrophizing on ongoing brain activity and movement-evoked brain activity during acute orofacial muscle pain. METHODS: Thirty-four healthy, pain-free subjects were recruited. In 17 subjects, the effect of catastrophizing on regional brain activity was determined. In 19 subjects, functional magnetic resonance imaging was used to determine the effects of pain catastrophizing on brain activation patterns during jaw movements in the presence of ongoing pain. RESULTS: We found that in the presence of pain, catastrophizing was significantly correlated with activity in multi-sensory integrative brain regions, including the dorsolateral and medial prefrontal cortices. Importantly, this relationship did not exist when subjects were not experiencing pain. In addition, during repetitive open-close jaw movements in the presence of pain, activity in the primary motor cortex, cerebellar cortex and the trigeminal motor nucleus was positively correlated with pain catastrophizing scores. In contrast, in the dorsolateral prefrontal cortex, as pain catastrophizing scores increased, the magnitude of signal intensity change during jaw movements decreased. Again, no such relationships occurred when the individual was not in pain. CONCLUSIONS: These data show that during pain, catastrophic thinking has a significant impact on activity in motor and sensory integrative regions. Reducing negative coping strategies may be an effective means in reducing fear avoidance behaviours and the intensity of ongoing pain.


Assuntos
Encéfalo/fisiopatologia , Catastrofização/fisiopatologia , Catastrofização/psicologia , Dor Facial/psicologia , Atividade Motora/fisiologia , Mialgia/psicologia , Adulto , Estudos de Casos e Controles , Dor Facial/fisiopatologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Mialgia/fisiopatologia , Medição da Dor/métodos , Adulto Jovem
14.
Neuroimage ; 124(Pt A): 54-62, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26343321

RESUMO

Conditioned pain modulation is a powerful analgesic mechanism, occurring when a painful stimulus is inhibited by a second painful stimulus delivered at a different body location. Reduced conditioned pain modulation capacity is associated with the development of some chronic pain conditions and the effectiveness of some analgesic medications. Human lesion studies show that the circuitry responsible for conditioned pain modulation lies within the caudal brainstem, although the precise nuclei in humans remain unknown. We employed brain imaging to determine brainstem sites responsible for conditioned pain modulation in 54 healthy individuals. In all subjects, 8 noxious heat stimuli (test stimuli) were applied to the right side of the mouth and brain activity measured using functional magnetic resonance imaging. This paradigm was then repeated. However, following the fourth noxious stimulus, a separate noxious stimulus, consisting of an intramuscular injection of hypertonic saline into the leg, was delivered (conditioning stimulus). During this test and conditioning stimulus period, 23 subjects displayed conditioned pain modulation analgesia whereas 31 subjects did not. An individual's analgesic ability was not influenced by gender, pain intensity levels of the test or conditioning stimuli or by psychological variables such as pain catastrophizing or fear of pain. Brain images were processed using SPM8 and the brainstem isolated using the SUIT toolbox. Significant increases in signal intensity were determined during each test stimulus and compared between subjects that did and did not display CPM analgesia (p<0.05, small volume correction). The expression of analgesia was associated with reduction in signal intensity increases during each test stimulus in the presence of the conditioning stimulus in three brainstem regions: the caudalis subdivision of the spinal trigeminal nucleus, i.e., the primary synapse, the region of the subnucleus reticularis dorsalis and in the dorsolateral pons in the region of the parabrachial nucleus. Furthermore, the magnitudes of these signal reductions in all three brainstem regions were significantly correlated to analgesia magnitude. Defining conditioned pain modulation circuitry provides a framework for the future investigations into the neural mechanisms responsible for the maintenance of persistent pain conditions thought to involve altered analgesic circuitry.


Assuntos
Tronco Encefálico/fisiopatologia , Percepção da Dor/fisiologia , Dor/fisiopatologia , Adulto , Mapeamento Encefálico , Feminino , Temperatura Alta , Humanos , Imageamento por Ressonância Magnética , Masculino , Dor/psicologia , Medição da Dor , Adulto Jovem
15.
J Laryngol Otol ; 128(11): 966-71, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25311108

RESUMO

OBJECTIVE: To create a 'one-stop' clinic in which assessment, diagnosis, treatment and therapies for most patients presenting with balance and dizziness disorders are delivered simultaneously. METHODS: Patients triaged via referral letters were selected to attend the balance clinic, which is led by specialist balance physiotherapists. Patients were seen by an audiologist, and a 'balance' ENT consultant was available for joint consultations when required. Further details of the clinic set up are discussed. RESULTS: Over an 18-month period, 200 new 'dizzy' patients attended the clinic. Benign paroxysmal positional vertigo and labyrinthitis were the commonest diagnoses. Fifty per cent of all patients were discharged after a single clinic visit. Questionnaires showed that patient satisfaction was high. CONCLUSION: The physiotherapy-led balance clinic has reduced patient waiting times to be seen, has a high level of patient satisfaction and is economically beneficial.


Assuntos
Instituições de Assistência Ambulatorial/organização & administração , Tontura/diagnóstico , Tontura/reabilitação , Modalidades de Fisioterapia/organização & administração , Vertigem/diagnóstico , Vertigem/reabilitação , Idoso , Técnicas de Diagnóstico Otológico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente
16.
Pain ; 155(5): 1027-1036, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24530612

RESUMO

There is increasing evidence relating thalamic changes to the generation and/or maintenance of neuropathic pain. We have recently reported that neuropathic orofacial pain is associated with altered thalamic anatomy, biochemistry, and activity, which may result in disturbed thalamocortical oscillatory circuits. Despite this evidence, it is possible that these thalamic changes are not responsible for the presence of pain per se, but result as a consequence of the injury. To clarify this subject, we compared brain activity and biochemistry in 12 people with below-level neuropathic pain after complete thoracic spinal cord injury with 11 people with similar injuries and no neuropathic pain and 21 age- and gender-matched healthy control subjects. Quantitative arterial spinal labelling was used to measure thalamic activity, and magnetic resonance spectroscopy was used to determine changes in neuronal variability quantifying N-acetylaspartate and alterations in inhibitory function quantifying gamma amino butyric acid. This study revealed that the presence of neuropathic pain is associated with significant changes in thalamic biochemistry and neuronal activity. More specifically, the presence of neuropathic pain after spinal cord injury is associated with significant reductions in thalamic N-acetylaspartate, gamma amino butyric acid content, and blood flow in the region of the thalamic reticular nucleus. Spinal cord injury on its own did not account for these changes. These findings support the hypothesis that neuropathic pain is associated with altered thalamic structure and function, which may disturb central processing and play a key role in the experience of neuropathic pain.


Assuntos
Neuralgia/fisiopatologia , Traumatismos da Medula Espinal/fisiopatologia , Tálamo/fisiopatologia , Adulto , Idoso , Ácido Aspártico/análogos & derivados , Ácido Aspártico/metabolismo , Feminino , Neuroimagem Funcional , Humanos , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neuralgia/etiologia , Neuralgia/metabolismo , Medição da Dor , Marcadores de Spin , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/metabolismo , Tálamo/metabolismo
17.
Carbohydr Polym ; 91(2): 549-59, 2013 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-23121944

RESUMO

The TiO(2) nanowire (TiO(2) Nw) was successfully prepared via hydrothermal method through TiO(2) nanoparticle (TiO(2) Np). TiO(2) Np doped silver and TiO(2) Nw doped silver were prepared via photo-reducing Ag(+) ions to Ag metal on the TiO(2) Np or TiO(2) Nw surfaces. The prepared nanomaterials were evaluated using X-ray (XRD) diffraction pattern, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Bleached untreated cotton fabric and PVP treated cotton fabrics were coated with the synthesized nanomaterials using pad-dry-cure method. Photocatalytic activity of untreated and coated cotton fabrics with TiO(2) nanomaterials was investigated through the fabric self cleaning of MB dye stains. Also, the PVP finished cotton fabric modified by nanomaterials demonstrated antimicrobial activity against Gram positive bacteria, Gram negative bacteria and fungi. The mechanical properties of coated cotton fabric (tear strength, surface roughness, tensile strength and elongation at break) were examined.


Assuntos
Anti-Infecciosos/farmacologia , Nanofios , Têxteis , Titânio/farmacologia , Catálise/efeitos da radiação , Fibra de Algodão , Fungos/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Nanopartículas Metálicas/uso terapêutico , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Povidona/farmacologia , Compostos de Prata , Resistência à Tração , Titânio/química
18.
Carbohydr Polym ; 90(2): 1003-7, 2012 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-22840032

RESUMO

Conducting polymers have generated a great deal of interest because of their physical and chemical properties as well as their potential application in industry particularly in packaging applications. However one of short comings of most conducting polymer is that they are often formed as intractable films that are difficult to process. To overcome this problem we have incorporated conducting polymer, namely polyaniline into sheets of paper in order to create new composite material which combine the universal properties of paper product with the chemical and electrically conducting properties of the conducting polymer. Paper conducting polymer composite have been prepared by polymerizing aniline directly onto the paper sheet using ammonium peroxydisulfate (APS) as an oxidant at different temperatures. The prepared composite was characterized by FT-IR and SEM. The thermo-oxidative degradation was studied by thermo gravimetric analysis (TGA); electrical conductivities measurements of the composites were significantly increased over those of the precursor paper.


Assuntos
Compostos de Anilina/química , Papel , Polímeros/química , Análise Diferencial Térmica , Condutividade Elétrica , Microscopia Eletrônica de Varredura , Modelos Biológicos , Nanocompostos/química , Nanocompostos/ultraestrutura , Polímeros/síntese química , Polímeros/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura
19.
Arzneimittelforschung ; 62(2): 63-74, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22344550

RESUMO

Novel benzimidazoles, benzothiazoles and benzofurans incorporating pyrazole moiety have been synthesized and screened for their antiangogenic activities, by testing their ability to inhibit human umbilical vein endothelial cell (HUVEC) proliferation, cord formation and migration in response to chemoattractant. 3 compounds 19, 23 and 26 showed antiangiogenic activities at non-cytotoxic concentrations. Compound 19 was the most active with chemotaxis activity data nearly comparable to that of the positive control, TNP-470. Compound 42 showed a significant cytotoxic effect on the tested cancer cell lines and less antiangiogenesis activity compared to compounds 19, 23 and 26. All the tested compounds, in contrary to TNP-470, interfered with the migratory function of HUVECs in response to vascular endothelial growth factor rather than the endothelial cells proliferation or cord formation. Moreover, a docked pose of compounds 19 and 26 was obtained bound to kinase insert domain receptor using Molecular Operating Environment module.


Assuntos
Inibidores da Angiogênese/síntese química , Inibidores da Angiogênese/farmacologia , Benzimidazóis/síntese química , Benzimidazóis/farmacologia , Benzofuranos/síntese química , Benzofuranos/farmacologia , Benzotiazóis/síntese química , Benzotiazóis/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Células Endoteliais/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana , Humanos , Indicadores e Reagentes , Espectroscopia de Ressonância Magnética , Pirazóis , Espectrofotometria Infravermelho , Relação Estrutura-Atividade
20.
Eur J Med Chem ; 44(2): 609-24, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18462840

RESUMO

The 5,10-dihydro-2-thioxo-pyrimido[4,5-b]quinolines (2a-c) and its oxidized form 3 were prepared and used as key intermediates for the synthesis of thiazolo[3',2':1,2]pyrimido[4,5-b]-quinolines (5a-c), isoxazolo[5'',4'':4',5']thiazolo[3',2':1,2]pyrimido[4,5-b]quinolines (6a-c), 4-chloro-2-methylthio-pyrimido[4,5-b]quinoline, its amino derivatives (19-21) and 10,11,12,13-tetrahydro-5H-quino[2',3':4,5]pyrimido[6,1-b]quinazoline (22). The newly synthesized compounds were characterized by IR, NMR (1H, 13C) and mass spectral studies. Representative of the synthesized compounds was tested and evaluated for anti-oxidant, anti-inflammatory and analgesic activities. Compounds 2a-c showed the highest inhibitory anti-oxidant activity either using erythrocyte hemolysis or ABTS methods. Compounds 2a, 10b, 16, and 17a manifested the best protective effect against DNA damage induced by bleomycin. Compounds 2c, 5a, 20a, 2a, and 2b exhibited a potent anti-inflammatory activity using carrageenan-induced paw edema test in rats.


Assuntos
Analgésicos/síntese química , Anti-Inflamatórios/síntese química , Antioxidantes/síntese química , Quinolinas/síntese química , Analgésicos/farmacologia , Animais , Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Encéfalo , Dano ao DNA/efeitos dos fármacos , Desenho de Fármacos , Edema/tratamento farmacológico , Edema/prevenção & controle , Eritrócitos/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Rim , Quinolinas/farmacologia , Ratos , Análise Espectral
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