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1.
Sensors (Basel) ; 23(24)2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38139688

RESUMO

Gliomas, a prevalent category of primary malignant brain tumors, pose formidable clinical challenges due to their invasive nature and limited treatment options. The current therapeutic landscape for gliomas is constrained by a "one-size-fits-all" paradigm, significantly restricting treatment efficacy. Despite the implementation of multimodal therapeutic strategies, survival rates remain disheartening. The conventional treatment approach, involving surgical resection, radiation, and chemotherapy, grapples with substantial limitations, particularly in addressing the invasive nature of gliomas. Conventional diagnostic tools, including computed tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography (PET), play pivotal roles in outlining tumor characteristics. However, they face limitations, such as poor biological specificity and challenges in distinguishing active tumor regions. The ongoing development of diagnostic tools and therapeutic approaches represents a multifaceted and promising frontier in the battle against this challenging brain tumor. The aim of this comprehensive review is to address recent advances in diagnostic tools and therapeutic approaches for gliomas. These innovations aim to minimize invasiveness while enabling the precise, multimodal targeting of localized gliomas. Researchers are actively developing new diagnostic tools, such as colorimetric techniques, electrochemical biosensors, optical coherence tomography, reflectometric interference spectroscopy, surface-enhanced Raman spectroscopy, and optical biosensors. These tools aim to regulate tumor progression and develop precise treatment methods for gliomas. Recent technological advancements, coupled with bioelectronic sensors, open avenues for new therapeutic modalities, minimizing invasiveness and enabling multimodal targeting with unprecedented precision. The next generation of multimodal therapeutic strategies holds potential for precision medicine, aiding the early detection and effective management of solid brain tumors. These innovations offer promise in adopting precision medicine methodologies, enabling early disease detection, and improving solid brain tumor management. This review comprehensively recognizes the critical role of pioneering therapeutic interventions, holding significant potential to revolutionize brain tumor therapeutics.


Assuntos
Neoplasias Encefálicas , Glioma , Humanos , Glioma/diagnóstico , Glioma/terapia , Glioma/patologia , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/terapia , Encéfalo/patologia , Imageamento por Ressonância Magnética , Tomografia por Emissão de Pósitrons/métodos
2.
Mar Drugs ; 20(12)2022 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-36547919

RESUMO

Marine algal species comprise of a large portion of polysaccharides which have shown multifunctional properties and health benefits for treating and preventing human diseases. Laminarin, or ß-glucan, a storage polysaccharide from brown algae, has been reported to have potential pharmacological properties such as antioxidant, anti-tumor, anti-coagulant, anticancer, immunomodulatory, anti-obesity, anti-diabetic, anti-inflammatory, wound healing, and neuroprotective potential. It has been widely investigated as a functional material in biomedical applications as it is biodegradable, biocompatible, and is low toxic substances. The reported preclinical and clinical studies demonstrate the potential of laminarin as natural alternative agents in biomedical and industrial applications such as nutraceuticals, pharmaceuticals, functional food, drug development/delivery, and cosmeceuticals. This review summarizes the biological activities of laminarin, including mechanisms of action, impacts on human health, and reported health benefits. Additionally, this review also provides an overview of recent advances and identifies gaps and opportunities for further research in this field. It further emphasizes the molecular characteristics and biological activities of laminarin in both preclinical and clinical settings for the prevention of the diseases and as potential therapeutic interventions.


Assuntos
Glucanos , Phaeophyceae , Humanos , Glucanos/farmacologia , Polissacarídeos/farmacologia , Preparações Farmacêuticas
3.
J Sci Food Agric ; 102(14): 6293-6298, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35514139

RESUMO

BACKGROUND: Hempseed meal, a by-product of the hempseed oil processing stream, is a potential alternative source for food proteins. Efficient extraction of proteins from hempseed meal is challenging owing to differences in the structure and solubility of various protein fractions present in the seed. In the present study, protein was extracted from hempseed meal using four different solvents, including aqueous NaOH, KOH, NaHCO3 and NaCl, at four different concentrations with the aim of improving the recovery of protein fractions rich in essential amino acids. RESULTS: Extraction using alkaline solvents provided superior protein recovery (60-78%) compared with NaCl solution and control extractions (20-48% and 21%, respectively). The concentration of alkali or salt (0.25-1 mol L-1 ) had a minor but significant impact on the yield. Amino acid composition analysis revealed that hempseed meal contains 24% (54.5 ± 0.19 mg g-1 ) essential amino acids of total amino acids, and extraction with NaOH, KOH, NaHCO3 or NaCl did not improve the selective extraction of essential amino acids compared to control experiments. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis allowed the identification of edestin and albumin in the extracts obtained with NaHCO3 and NaCl solvents, with results further showing that the type of extraction solvent influences protein extraction selectivity. CONCLUSION: Although alkali solvents provide superior extraction yields, extraction with water resulted in extracts containing the highest proportion of proteins bearing essential amino acids. According to the results of SDS-PAGE, extraction using alkali solvents induced protein crosslinking. © 2022 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Assuntos
Sementes , Cloreto de Sódio , Albuminas/química , Aminoácidos/análise , Aminoácidos Essenciais/análise , Cannabis , Extratos Vegetais , Sementes/química , Cloreto de Sódio/análise , Dodecilsulfato de Sódio/análise , Hidróxido de Sódio , Solventes/química , Água/análise
4.
Bioorg Med Chem Lett ; 31: 127672, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33161126

RESUMO

The G-protein coupled receptor - GPR120 has recently been implicated as a novel target for colorectal cancer (CRC) and other cancer managements. In this study, a homology model of GPR120S (short isoform) was generated to identify potential anti-cancer compounds targeting the GPR120 receptor using a combined in silico docking-based virtual screening (DBVS), structure-activity relationships (SAR) and in vitro screening approach. SPECS database of synthetic chemical compounds (~350,000) was screened using the developed GPR120S model to identify molecules binding to the orthosteric binding pocket followed by an AutoDock SMINA rigid-flexible docking protocol. The best 13 hit molecules were then tested in vitro to evaluate their cytotoxic activity against SW480 - human CRC cell line expressing GPR120. The test compound 1 (3-​(4-​methylphenyl)​-​2-​[(2-​oxo-​2-​phenylethyl)​sulfanyl]​-​5,6-​dihydrospiro(benzo[h]​quinazoline-​5,1'-​cyclopentane)​-​4(3H)​-​one) showed ~ 90% inhibitory effects on cell growth with micromolar affinities (IC50 = 23.21-26.69 µM). Finally, SAR analysis of compound 1 led to the identification of a more active compound from the SPECS database showing better efficacy during cell-based cytotoxicity assay -5 (IC50 = 5.89-6.715 µM), while a significant reduction in cytotoxic effects of 5 was observed in GPR120-siRNA pre-treated SW480 cells. The GPR120S homology model generated, and SAR analysis conducted by this work discovered a potential chemical scaffold, dihydrospiro(benzo[h]quinazoline-5,1'-cyclopentane)-4(3H)-one, which will aid future research on anti-cancer drug development for CRC management.


Assuntos
Antineoplásicos/farmacologia , Ciclopentanos/farmacologia , Receptores Acoplados a Proteínas G/antagonistas & inibidores , Antineoplásicos/síntese química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Ciclopentanos/síntese química , Ciclopentanos/química , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Simulação de Acoplamento Molecular , Estrutura Molecular , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Relação Estrutura-Atividade , Células Tumorais Cultivadas
5.
Nanomedicine ; 36: 102436, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34153528

RESUMO

Platinum nanoparticles (PtNPs) have been investigated for their antioxidant abilities in a range of biological and other applications. The ability to reduce off-target cold atmospheric plasma (CAP) cytotoxicity would be useful in Plasma Medicine; however, little has been published to date about the ability of PtNPs to reduce or inhibit the effects of CAP. Here we investigate whether PtNPs can protect against CAP-induced cytotoxicity in cancerous and non-cancerous cell lines. PtNPs were shown to dramatically reduce intracellular reactive species (RONS) production in U-251 MG cells. However, RONS generation was unaffected by PtNPs in medium without cells. PtNPs protect against CAP induced mitochondrial membrane depolarization, but not cell membrane permeabilization which is a CAP-induced RONS-independent event. PtNPs act as potent intracellular scavengers of reactive species and can protect against CAP induced cytotoxicity. PtNPs, showing no significant biocorrosion, may be useful as a catalytic antioxidant for healthy tissue and for protecting against CAP-induced tissue damage.


Assuntos
Citotoxinas/efeitos adversos , Nanopartículas Metálicas , Estresse Oxidativo/efeitos dos fármacos , Gases em Plasma/efeitos adversos , Platina , Espécies Reativas de Oxigênio/metabolismo , Linhagem Celular Tumoral , Citotoxinas/farmacologia , Células HEK293 , Humanos , Nanopartículas Metálicas/química , Nanopartículas Metálicas/uso terapêutico , Gases em Plasma/farmacologia , Platina/química , Platina/farmacologia
6.
Mar Drugs ; 19(4)2021 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-33920329

RESUMO

The exponential growth of emerging multidrug-resistant microorganisms, including foodborne pathogens affecting the shelf-life and quality of foods, has recently increased the needs of the food industry to search for novel, natural and eco-friendly antimicrobial agents. Macroalgae are a bio-diverse group distributed worldwide, known to produce multiple compounds of diverse chemical nature, different to those produced by terrestrial plants. These novel compounds have shown promising health benefits when incorporated into foods, including antimicrobial properties. This review aims to provide an overview of the general methods and novel compounds with antimicrobial properties recently isolated and characterized from macroalgae, emphasizing the molecular pathways of their antimicrobial mechanisms of action. The current scientific evidence on the use of macroalgae or macroalgal extracts to increase the shelf-life of foods and prevent the development of foodborne pathogens in real food products and their influence on the sensory attributes of multiple foods (i.e., meat, dairy, beverages, fish and bakery products) will also be discussed, together with the main challenges and future trends of the use of marine natural products as antimicrobials.


Assuntos
Anti-Infecciosos/farmacologia , Microbiologia de Alimentos , Conservação de Alimentos , Conservantes de Alimentos/farmacologia , Doenças Transmitidas por Alimentos/prevenção & controle , Alga Marinha/metabolismo , Animais , Anti-Infecciosos/isolamento & purificação , Técnicas Bacteriológicas , Conservantes de Alimentos/isolamento & purificação , Doenças Transmitidas por Alimentos/microbiologia , Humanos , Estrutura Molecular , Relação Estrutura-Atividade
7.
Arch Biochem Biophys ; 689: 108462, 2020 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-32590068

RESUMO

Silver nanoparticles (AgNP) emerged as a promising reagent for cancer therapy with oxidative stress implicated in the toxicity. Meanwhile, studies reported cold atmospheric plasma (CAP) generation of reactive oxygen and nitrogen species has selectivity towards cancer cells. Gold nanoparticles display synergistic cytotoxicity when combined with CAP against cancer cells but there is a paucity of information using AgNP, prompting to investigate the combined effects of CAP using dielectric barrier discharge system (voltage of 75 kV, current is 62.5 mA, duty cycle of 7.5kVA and input frequency of 50-60Hz) and 10 nm PVA-coated AgNP using U373MG Glioblastoma Multiforme cells. Cytotoxicity in U373MG cells was >100-fold greater when treated with both CAP and PVA-AgNP compared with either therapy alone (IC50 of 4.30 µg/mL with PVA-AgNP alone compared with 0.07 µg/mL after 25s CAP and 0.01 µg/mL 40s CAP). Combined cytotoxicity was ROS-dependent and was prevented using N-Acetyl Cysteine. A novel darkfield spectral imaging method investigated and quantified AgNP uptake in cells determining significantly enhanced uptake, aggregation and subcellular accumulation following CAP treatment, which was confirmed and quantified using atomic absorption spectroscopy. The results indicate that CAP decreases nanoparticle size, decreases surface charge distribution of AgNP and induces uptake, aggregation and enhanced cytotoxicity in vitro.


Assuntos
Neoplasias Encefálicas/terapia , Glioblastoma/terapia , Gases em Plasma/farmacologia , Prata/farmacologia , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Glioblastoma/metabolismo , Humanos , Nanopartículas Metálicas/análise , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Prata/farmacocinética
8.
Inj Prev ; 25(5): 400-406, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-30279165

RESUMO

OBJECTIVE: Measure the impact of automated photo speed enforcement in school zones on motorist speed and speeding violation rates during school travel. METHODS: Automated enforcement cameras, active during school commuting hours, were installed around four elementary schools in Seattle, Washington, USA in 2012. We examined the effect of automated enforcement on motorist speeds and speed violation rates during the citation period (10 December 2012 to 15 January 2015) compared with the 'warning' period (1 November to 9 December 2012). We evaluated outcomes with an interrupted time series approach using multilevel mixed linear regression. RESULTS: Motorist speed violation rates decreased by nearly half in the citation period compared with the warning period (standardised incident rate ratio 0.53, 95% CI 0.42 to 0.66). The hourly maximum violation speed and mean hourly speeds decreased 2.1 MPH (95% CI -2.88 to -1.39) and 1.1 MPH (95% CI -1.64 to - 0.60), respectively. The impact of automated enforcement was sustained during the second year of implementation. CONCLUSION: Automated photo enforcement of speed limit in school zones was effective at reducing motorist speed violations and also achieved a significant reduction in mean motorist speed.


Assuntos
Prevenção de Acidentes/métodos , Acidentes de Trânsito/prevenção & controle , Condução de Veículo/estatística & dados numéricos , Aplicação da Lei/métodos , Humanos , Análise de Séries Temporais Interrompida , Fotografação/métodos
9.
Int J Mol Sci ; 20(24)2019 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-31842251

RESUMO

Lateral flow immunochromatographic assays are a powerful diagnostic tool for point-of-care tests, based on their simplicity, specificity, and sensitivity. In this study, a rapid and sensitive gold nanoparticle (AuNP) immunochromatographic strip is produced for detecting aflatoxin B1 (AFB1) in suspicious fungi-contaminated food samples. The 10 nm AuNPs were encompassed by bovine serum albumin (BSA) and AFB1 antibody. Thin-layer chromatography, gel electrophoresis and nuclear magnetic resonance spectroscopy were employed for analysing the chemical complexes. Various concentrations of AFB1 antigen (0-16 ng/mL) were tested with AFB1 antibody-BSA-AuNPs (conjugated AuNPs) and then analysed by scanning electron microscopy, ultraviolet-visible spectroscopy, and Zetasizer. The results showed that the AFB1 antibody was coupled to BSA by the N-hydroxysuccinimide ester method. The AuNPs application has the potential to contribute to AFB1 detection by monitoring a visible colour change from red to purple-blue, with a detection limit of 2 ng/mL in a 96-well plate. The lateral flow immunochromatographic strip tests are rapid, taking less than 10 min., and they have a detection capacity of 10 ng/g. The smartphone analysis of strips provided the results in 3 s, with a detection limit of 0.3 ng/g for AFB1 when the concentration was below 10 ng/g. Excellent agreement was found with AFB1 determination by high-performance liquid chromatography in the determination of AFB1 among 20 samples of peanuts, corn, rice, and bread.


Assuntos
Aflatoxina B1 , Antifúngicos/farmacologia , Ouro , Nanopartículas Metálicas , Fitas Reagentes , Aflatoxina B1/química , Antifúngicos/química , Cromatografia de Afinidade/métodos , Cromatografia Líquida de Alta Pressão , Contaminação de Alimentos/análise , Ouro/química , Nanopartículas Metálicas/química , Estrutura Molecular , Espectroscopia de Prótons por Ressonância Magnética , Albumina Sérica/química
10.
J Mater Sci Mater Med ; 29(9): 144, 2018 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-30155669

RESUMO

This paper reports the corrosion resistant and cytocompatible properties of the hyaluronic acid-silane coating on AZ31 Mg alloy. In this study, the osteoinductive properties of high molecular weight hyaluronic acid (HA, 1-4 MDa) and the corrosion protection of silane coatings were incorporated as a composite coating on biodegradable AZ31 Mg alloy for orthopaedic applications. The multi-step fabrication of coatings first involved dip coating of a passivated AZ31 Mg alloy with a methyltriethoxysilane-tetraethoxysilane sol-gel to deposit a dense, cross-linked and corrosion resistant silane coating (AZ31-MT). The second step was to create an amine-functionalised surface by treating coated alloy with 3-aminopropyl-triethoxy silane (AZ31-MT-A) which facilitated the immobilisation of HA via EDC-NHS coupling reactions at two different concentrations i.e 1 mg.ml-1 (AZ31-MT-A-HA1) and 2 mg.ml-1 (AZ31-MT-A-HA2). These coatings were characterised by Fourier transform infrared spectroscopy, atomic force microscopy and static contact angle measurements which confirmed the successful assembly of the full coatings onto AZ31 Mg alloy. The influence of HA-silane coating on the corrosion of Mg alloy was investigated by electrical impedance spectroscopy and long-term immersion studies measurements in HEPES buffered DMEM. The results showed an enhanced corrosion resistance of HA functionalised silane coated AZ31 substrate over the uncoated equivalent alloy. Furthermore, the cytocompatibility of MC3T3-E1 osteoblasts was evaluated on HA-coated AZ31-MT-A substrates by live-dead staining, quantification of total cellular DNA content, scanning electron microscope and alkaline phosphatase activity. The results showed HA concentration-dependent improvement of osteoblast cellular response in terms of enhanced cell adhesion, proliferation and differentiation. These findings hold great promise in employing such biomimetic multifunctional coatings to improve the corrosion resistance and cytocompatibility of biodegradable Mg-based alloy for orthopaedic applications.


Assuntos
Ligas/química , Materiais Biocompatíveis , Ácido Hialurônico/química , Compostos de Magnésio/química , Silanos/química , Células 3T3 , Animais , Sobrevivência Celular , Eletroquímica , Hidrogênio/química , Concentração de Íons de Hidrogênio , Teste de Materiais , Camundongos , Osteoblastos , Próteses e Implantes , Propriedades de Superfície
11.
Anal Bioanal Chem ; 409(19): 4647-4658, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28573322

RESUMO

Fungi, which are common in the environment, can cause a multitude of diseases. Warm, humid conditions allow fungi to grow and infect humans via the respiratory, digestive and reproductive tracts, genital area and other bodily interfaces. Fungi can be detected directly by microscopy, using the potassium hydroxide test, which is the gold standard and most popular method for fungal screening. However, this test requires trained personnel operating specialist equipment, including a fluorescent microscope and culture facilities. As most acutely infected patients seek medical attention within the first few days of symptoms, the optimal diagnostic test would be rapid and self-diagnostic simplifying and improving the therapeutic outcome. In suspensions of gold nanoparticles, Aspergillus niger can cause a colour change from red to blue within 2 min, as a result of changes in nanoparticle shape. A similar colour change was observed in the supernatant of samples of human toenails dispersed in water. Scanning electron microscopy, UV/Vis and Raman spectroscopy were employed to monitor the changes in morphology and surface plasmon resonance of the nanoparticles. The correlation of colour change with the fungal infection was analysed using the absorbance ratio at 520 nm/620 nm. We found a decrease in the ratio when the fungi concentration increased from 1 to 16 CFU/mL, with a detection limit of 10 CFU/mL. The test had an 80% sensitivity and a 95% specificity value for the diagnosis of athlete's foot in human patients. This plasmonic gold nanoparticle-based system for detection of fungal infections measures the change in shape of gold nanoparticles and generates coloured solutions with distinct tonality. Our application has the potential to contribute to self-diagnosis and hygiene control in laboratories/hospitals with fewer resources, just using the naked eye. Graphical abstract Colorimetric method for fungi detection with gold nano particles.


Assuntos
Dermatomicoses/microbiologia , Fungos/isolamento & purificação , Ouro/química , Nanopartículas Metálicas/química , Dermatomicoses/diagnóstico , Humanos , Microscopia Eletrônica de Varredura , Análise Espectral Raman
12.
Br J Cancer ; 114(4): 435-43, 2016 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-26882067

RESUMO

BACKGROUND: Non-thermal atmospheric plasma (NTAP) is an ionised gas produced under high voltage that can generate short-lived chemically active species and induce a cytotoxic insult in cancer cells. Cell-specific resistance to NTAP-mediated cytotoxicity has been reported in the literature. The aim of this study was to determine whether resistance against NTAP could be overcome using the human glioma cell line U373MG. METHODS: Non-thermal atmospheric plasma was generated using a Dielectric Barrier Device (DBD) system with a maximum voltage output of 120 kV at 50 Hz. The viability of U373MG GBM cells and HeLa cervical carcinoma cells was determined using morphology, flow cytometry and cytotoxicity assays. Fluorescent probes and inhibitors were used to determine the mechanisms of cytotoxicity of cells exposed to the plasma field. Combinational therapy with temozolomide (TMZ) and multi-dose treatments were explored as mechanisms to overcome resistance to NTAP. RESULTS: Non-thermal atmospheric plasma decreased cell viability in a dose (time)-dependent manner. U373MG cells were shown to be resistant to NTAP treatment when compared with HeLa cells, and the levels of intracellular reactive oxygen species (ROS) quantified in U373MG cells were much lower than in HeLa cells following exposure to the plasma field. Reactive oxygen species inhibitor N-acetyl cysteine (NAC) only alleviated the cytotoxic effects in HeLa cells and not in the relatively NTAP-resistant cell line U373MG. Longer exposures to NTAP induced a cell death independent of ROS, JNK and caspases in U373MG. The relative resistance of U373MG cells to NTAP could be overcome when used in combination with low concentrations of the GBM chemotherapy TMZ or exposure to multiple doses. CONCLUSIONS: For the very first time, we report that NTAP induces an ROS-, JNK- and caspase-independent mechanism of cell death in the U373MG GBM cell line that can be greatly enhanced when used in combination with low doses of TMZ. Further refinement of the technology may facilitate localised activation of cytotoxicity against GBM when used in combination with new and existing chemotherapeutic regimens.


Assuntos
Antineoplásicos Alquilantes/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Dacarbazina/análogos & derivados , Glioma/tratamento farmacológico , Glioma/patologia , Gases em Plasma/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Linhagem Celular Tumoral , Dacarbazina/farmacologia , Sinergismo Farmacológico , Células HeLa , Humanos , Temozolomida
13.
Nanomaterials (Basel) ; 14(10)2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38786811

RESUMO

Foodborne illnesses can be infectious and dangerous, and most of them are caused by bacteria. Some common food-related bacteria species exist widely in nature and pose a serious threat to both humans and animals; they can cause poisoning, diseases, disabilities and even death. Rapid, reliable and cost-effective methods for bacterial detection are of paramount importance in food safety and environmental monitoring. Polymerase chain reaction (PCR), lateral flow immunochromatographic assay (LFIA) and electrochemical methods have been widely used in food safety and environmental monitoring. In this paper, the recent developments (2013-2023) covering PCR, LFIA and electrochemical methods for various bacterial species (Salmonella, Listeria, Campylobacter, Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli)), considering different food sample types, analytical performances and the reported limit of detection (LOD), are discussed. It was found that the bacteria species and food sample type contributed significantly to the analytical performance and LOD. Detection via LFIA has a higher average LOD (24 CFU/mL) than detection via electrochemical methods (12 CFU/mL) and PCR (6 CFU/mL). Salmonella and E. coli in the Pseudomonadota domain usually have low LODs. LODs are usually lower for detection in fish and eggs. Gold and iron nanoparticles were the most studied in the reported articles for LFIA, and average LODs were 26 CFU/mL and 12 CFU/mL, respectively. The electrochemical method revealed that the average LOD was highest for cyclic voltammetry (CV) at 18 CFU/mL, followed by electrochemical impedance spectroscopy (EIS) at 12 CFU/mL and differential pulse voltammetry (DPV) at 8 CFU/mL. LOD usually decreases when the sample number increases until it remains unchanged. Exponential relations (R2 > 0.95) between LODs of Listeria in milk via LFIA and via the electrochemical method with sample numbers have been obtained. Finally, the review discusses challenges and future perspectives (including the role of nanomaterials/advanced materials) to improve analytical performance for bacterial detection.

14.
PLoS One ; 19(4): e0300467, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38593146

RESUMO

Liposome nanoparticles can carry a wide range of therapeutic molecules including small molecules and nucleic acid-based therapeutics. Potential benefits include translocation across physiological barriers, reduced systemic toxicity, and enhanced pharmacokinetic parameters such as absorption, distribution, selective release and optimal elimination kinetics. Liposome nanoparticles can be generated with a wide range of natural and synthetic lipid-based molecules that confer desirable properties depending on the desired therapeutic application Nel et al (2023), Large (2021), Elkhoury (2020). This protocol article seeks to detail the procedures involved in the production of cationic liposomes using thin-film dispersed hydration method with an estimated uniform size of 60-70 nm for targeted drug administration in tumor cells, by modifying the previous one also published by the same authors cited here. The method was carrying out using N-[1-(2,3-dioleoyloxy)propyl]-N,N,N-trimethylammonium methyl (DOTAP, 2 mg) as cationic lipid and cholesterol (0.5 mg) in a molar ratio of 7:3 respectively. The liposomal suspension was obtained and its physical, chemical and biological properties were determined. A two-step extrusion process, using 100 nm and 50 nm polycarbonate membranes, was carried. The results demonstrate generation of liposome nanoparticles with a size of 60-70 nm stable for at least 16 weeks and with an encapsulation efficiency of approximately 81% using Doxorubicin.


Assuntos
Nanopartículas , Ácidos Nucleicos , Lipossomos/química , Nanopartículas/química , Doxorrubicina , Lipídeos/química
15.
Sci Rep ; 14(1): 6214, 2024 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-38486008

RESUMO

Fucoidan has attracted considerable attention from scientists and pharmaceutical companies due to its antioxidant, anticoagulant, anti-inflammatory, anti-tumor, and health-enhancing properties. However, the extraction of fucoidan from seaweeds often involves the use of harsh chemicals, which necessitates the search for alternative solvents. Additionally, the high viscosity and low cell permeability of high molecular weight (Mw) fucoidan can limit its effectiveness in drug action, while lower Mw fractions exhibit increased biological activity and are also utilized as dietary supplements. The study aimed to (1) extract fucoidan from the seaweed Fucus vesiculosus (FV) using an environmentally friendly solvent and compare it with the most commonly used extraction solvent, hydrochloric acid, and (2) assess the impact of ultrasound-assisted depolymerization on reducing the molecular weight of the fucoidan extracts and examine the cytotoxic effect of different molecular weight fractions. The findings indicated that the green depolymerization solvent, in conjunction with a brief ultrasound treatment, effectively reduced the molecular weight. Moreover, a significant decrease in cell viability was observed in selected samples, indicating potential anticancer properties. As a result, ultrasound was determined to be an effective method for depolymerizing crude fucoidan from Fucus Vesiculosus seaweed.


Assuntos
Fucus , Polissacarídeos , Alga Marinha , Alga Marinha/química , Fucus/química , Anticoagulantes , Solventes
16.
Proc Natl Acad Sci U S A ; 107(32): 14443-8, 2010 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-20660723

RESUMO

Soluble antigens diffuse out of the brain and can thus stimulate a systemic immune response, whereas particulate antigens (from infectious agents or tumor cells) remain within brain tissue, thus failing to stimulate a systemic immune response. Immune privilege describes how the immune system responds to particulate antigens localized selectively within the brain parenchyma. We believe this immune privilege is caused by the absence of antigen presenting dendritic cells from the brain. We tested the prediction that expression of fms-like tyrosine kinase ligand 3 (Flt3L) in the brain will recruit dendritic cells and induce a systemic immune response against exogenous influenza hemagglutinin in BALB/c mice. Coexpression of Flt3L with HA in the brain parenchyma induced a robust systemic anti-HA immune response, and a small response against myelin basic protein and proteolipid protein epitopes. Depletion of CD4(+)CD25+ regulatory T cells (Tregs) enhanced both responses. To investigate the autoimmune impact of these immune responses, we characterized the neuropathological and behavioral consequences of intraparenchymal injections of Flt3L and HA in BALB/c and C57BL/6 mice. T cell infiltration in the forebrain was time and strain dependent, and increased in animals treated with Flt3L and depleted of Tregs; however, we failed to detect widespread defects in myelination throughout the forebrain or spinal cord. Results of behavioral tests were all normal. These results demonstrate that Flt3L overcomes the brain's immune privilege, and supports the clinical development of Flt3L as an adjuvant to stimulate clinically effective immune responses against brain neo-antigens, for example, those associated with brain tumors.


Assuntos
Encéfalo/imunologia , Sistema Imunitário/imunologia , Tirosina Quinase 3 Semelhante a fms/imunologia , Adjuvantes Imunológicos , Animais , Antígenos/imunologia , Células Dendríticas/imunologia , Hemaglutininas/imunologia , Imunidade , Ligantes , Camundongos , Camundongos Endogâmicos BALB C , Prosencéfalo/imunologia , Medula Espinal/imunologia , Linfócitos T Reguladores/imunologia
17.
Drug Discov Today ; 28(2): 103426, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36332834

RESUMO

This review focuses on recent advances in 3D culture systems that promise more accurate therapeutic models of the glioblastoma multiforme (GBM) tumor microenvironment (TME), such as the unique anatomical, cellular, and molecular features evident in human GBM. The key components of a GBM TME are outlined, including microbiomes, vasculature, extracellular matrix (ECM), infiltrating parenchymal and peripheral immune cells and molecules, and chemical gradients. 3D culture systems are evaluated against 2D culture systems and in vivo animal models. The main 3D culture techniques available are compared, with an emphasis on identifying key gaps in knowledge for the development of suitable platforms to accurately model the intricate components of the GBM TME.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Animais , Humanos , Linhagem Celular Tumoral , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Glioblastoma/tratamento farmacológico , Glioblastoma/patologia , Microambiente Tumoral
18.
Biomolecules ; 13(2)2023 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-36830755

RESUMO

Seaweed is in the spotlight as a promising source of nutrition for humans as the search for sustainable food production systems continues. Seaweed has a well-documented rich nutritional profile containing compounds such as polyphenols, carotenoids and polysaccharides as well as proteins, fatty acids and minerals. Seaweed processing for the extraction of functional ingredients such as alginate, agar, and carrageenan is well-established. Novel pretreatments such as ultrasound assisted extraction or high-pressure processing can be incorporated to more efficiently extract these targeted ingredients. The scope of products that can be created using seaweed are wide ranging: from bread and noodles to yoghurt and milk and even as an ingredient to enhance the nutritional profile and stability of meat products. There are opportunities for food producers in this area to develop novel food products using seaweed. This review paper discusses the unique properties of seaweed as a food, the processes involved in seaweed aquaculture, and the products that can be developed from this marine biomass. Challenges facing the industry such as consumer hesitation around seaweed products, the safety of seaweed, and processing hurdles will also be discussed.


Assuntos
Alga Marinha , Humanos , Carragenina , Polissacarídeos , Alginatos , Verduras
19.
PLoS One ; 18(2): e0276248, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36753513

RESUMO

Three-dimensional (3D) cell culture models can help bridge the gap between in vitro cell cultures and in vivo responses by more accurately simulating the natural in vivo environment, shape, tissue stiffness, stressors, gradients and cellular response while avoiding the costs and ethical concerns associated with animal models. The inclusion of the third dimension in 3D cell culture influences the spatial organization of cell surface receptors that interact with other cells and imposes physical restrictions on cells in compared to Two-dimensional (2D) cell cultures. Spheroids' distinctive cyto-architecture mimics in vivo cellular structure, gene expression, metabolism, proliferation, oxygenation, nutrition absorption, waste excretion, and drug uptake while preserving cell-extracellular matrix (ECM) connections and communication, hence influencing molecular processes and cellular phenotypes. This protocol describes the in vitro generation of tumourspheroids using the low attachment plate, hanging drop plate, and cellusponge natural scaffold based methods. The expected results from these protocols confirmed the ability of all these methods to create uniform tumourspheres.


Assuntos
Glioblastoma , Animais , Glioblastoma/metabolismo , Técnicas de Cultura de Células/métodos , Esferoides Celulares , Matriz Extracelular/metabolismo
20.
Foods ; 12(15)2023 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-37569153

RESUMO

Hemp seeds are currently used mainly for oil extraction, generating waste that could be potentially exploited further as a source of proteins and other bioactives. This study aims to valorise hemp waste (Cannabis sativa, L.) from previous oil extraction as a source of protein by analysing the effect of high-pressure processing (HPP) pre-treatments (0-600 MPa; 4-8 min) combined with conventional or ultrasound-assisted extraction (UAE) methods on protein recovery/purity, amino acid composition, and protein structure. Overall, maximum protein recovery (≈62%) was achieved with HPP (200 MPa, 8 min) with UAE. The highest protein purity (≈76%) was achieved with HPP (200 MPa, 4 min) with UAE. Overall, UAE improved the extraction of all amino acids compared to conventional extraction independently of HPP pre-treatments. Arg/Lys ratios of the protein isolates ranged between 3.78 and 5.34, higher than other vegetable protein sources. SDS-PAGE did not show visible differences amongst the protein isolates. These results seem to indicate the advantages of the use of UAE for protein recovery in the food industry and the need for further studies to optimise HPP/UAE for an accurate estimation of processing costs and their effects on the composition and structure of proteins to contribute further to the circular economy.

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