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1.
Sci Rep ; 14(1): 14831, 2024 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-38937529

RESUMO

Pomegranate (Punica granatum L.) fruit quality depends on many traits including visual, biochemical and mineral characteristics. One of the negative traits is aril whitening (AW) which is a frequently observed disorder in hot and dry climates, that leads to decline in desirable fruit quality. Color, antioxidant, and mineral contents of the arils are of prime importance as quality traits. Therefore, this study aims to investigate the effect of shading and foliar minerals on fruit quality during the fruit development stages of pomegranate. Treatments included shaded (50% green net) and unshaded trees and foliar application of trees with potassium sulfate (K, 1% and 2%) or sodium silicate (Si, 0.05, 0.1 and 0.15%) during two growing seasons. Results showed that the severity of AW at harvest decreased significantly when trees were covered with shading compared to control. The color values of L* and °hue for arils were lower in fruits grown under shading conditions indicating darker red arils. Shading significantly reduced chilling injury in cold storage compared to open field fruits. Shading and Si 0.15% increased superoxide dismutase, and catalase enzymes activity while decreased Polyphenol oxidase and peroxidase. Covering trees with shading and Si 0.15% spray resulted in the highest total anthocyanin, antioxidant activity, and total phenolics content in the arils. Shading as well as Si 0.15% increased macronutrients content of the arils. The study concluded that covering pomegranate trees and spraying with Si in hot climate reduced AW, increased antioxidant traits, and led to higher fruit quality.


Assuntos
Antioxidantes , Frutas , Minerais , Punica granatum , Silicatos , Sulfatos , Antioxidantes/metabolismo , Frutas/química , Frutas/efeitos dos fármacos , Frutas/metabolismo , Punica granatum/química , Sulfatos/análise , Minerais/análise , Minerais/metabolismo , Cor , Antocianinas/análise , Antocianinas/metabolismo
2.
Mol Biol Rep ; 50(11): 9559-9573, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37776412

RESUMO

Cancer stem cells (CSCs) defined as a small fraction of cells within malignancies have been isolated from tumors with different histological origins with stem related characteristics such as self-replicating potential, tumorigenesis, and therapy resistance. The dynamic communication between CSCs and tumor microenvironment particularly immune cells orchestrates their fate and plasticity as well as the patient outcome. According to recent evidence, it has been reported that they harness different immunological pathways to escape immunosurveillance and express aberrantly immunomodulatory agents or decreased levels of factors forming antigen presenting machinery (APM), subsequently followed by impaired antigen presentation and suppressed immune detection. As effective therapies are expected to be able to eradicate CSCs, mechanistic understanding of such interactions can provide insights into causes of therapy failure particularly in immunotherapy. Also, it can contribute to enhance the practical interventions against CSCs and their immunomodulatory features resulting in CSCs eradication and improving patient clinical outcome. The aim of this review is to explain the present knowledge regarding the immunobiology of CSCs and the immunoevasion mechanisms they use.


Assuntos
Neoplasias , Humanos , Neoplasias/tratamento farmacológico , Carcinogênese/metabolismo , Imunomodulação , Imunoterapia , Células-Tronco Neoplásicas/metabolismo , Microambiente Tumoral
4.
Rev Neurosci ; 34(6): 613-633, 2023 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-36496351

RESUMO

Multiple sclerosis (MS) is an inflammatory disease related to the central nervous system (CNS) with a significant global burden. In this illness, the immune system plays an essential role in its pathophysiology and progression. The currently available treatments are not recognized as curable options and, at best, might slow the progression of MS injuries to the CNS. However, stem cell treatment has provided a new avenue for treating MS. Stem cells may enhance CNS healing and regulate immunological responses. Likewise, stem cells can come from various sources, including adipose, neuronal, bone marrow, and embryonic tissues. Choosing the optimal cell source for stem cell therapy is still a difficult verdict. A type of stem cell known as mesenchymal stem cells (MSCs) is obtainable from different sources and has a strong immunomodulatory impact on the immune system. According to mounting data, the umbilical cord and adipose tissue may serve as appropriate sources for the isolation of MSCs. Human amniotic epithelial cells (hAECs), as novel stem cell sources with immune-regulatory effects, regenerative properties, and decreased antigenicity, can also be thought of as a new upcoming contender for MS treatment. Overall, the administration of stem cells in different sets of animal and clinical trials has shown immunomodulatory and neuroprotective results. Therefore, this review aims to discuss the different types of stem cells by focusing on MSCs and their mechanisms, which can be used to treat and improve the outcomes of MS disease.


Assuntos
Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Esclerose Múltipla , Animais , Humanos , Esclerose Múltipla/terapia , Esclerose Múltipla/metabolismo , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/metabolismo
5.
Chemosphere ; 285: 131576, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34329134

RESUMO

Synthesis of value added products from wastes is of importance from different perspectives. Wood and paper industry produces tons of wastewaters that contains lignin. In this paper, we report a new approach, called solvent-shifting method, to synthesize lignin sulfonate nanoparticles (LS-NPs). The effective parameters on size of LS-NPs were carefully tuned and the size of LS-NPs was minimized by response surface methodology. The results suggested that LS-NPs with size of 53 nm can be synthesized at low lignin sulfonate concentration (0.28 g/mL), moderate surfactant concentration (0.32 g/mL) but relatively high anti-solvent content (92 mL of ethanol for 40 mL of the aqueous phase). The as-synthesized LS-NPs were characterized by different analytical techniques, where presence of various negatively charged functional groups on surface of LS-NPs was conformed. To investigate the potential of LS-NPs for adsorptive removal of pollutant molecules, basic red 2 (known as Safranin-O) was used as a model pollutant dye. The results suggested that the maximum removal occurs at alkaline pH, where there is strong electrostatic interactions between LS-NPs and cationic Safranin-O molecules. The adsorption capacity was 85.14 mg/gr, where the isotherm data was best described by Redlich-Peterson isotherm model. The kinetic data also revealed that the adsorption is very fast in the first 20 min, where there is three diffusional steps to complete the adsorption in 90 min. The results of this study could open up new window to the field of value-added products to synthesize waste-driven nanomaterials for environmental applications.


Assuntos
Poluentes Ambientais , Nanopartículas , Poluentes Químicos da Água , Adsorção , Cinética , Lignina , Solventes , Poluentes Químicos da Água/análise
6.
Int J Biol Macromol ; 160: 632-641, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32446897

RESUMO

In this study, a novel method is presented for producing lignin-sulfonate nanoparticles. Then, the effect of produced nanoparticles is investigated on enhancing the acetylation efficiency. For these purposes, lignin-sulfonate was isolated from black-liquor of pulp-and-paper mill wastewater. Next, lignin-sulfonate nanoparticles were obtained using the oil-in-water (O/W) microemulsion, followed by modification of micro/nano-lignin-sulfonate particles. The physical, chemical, and morphological properties of lignin sulfonate micro/nanoparticles and modified forms of both samples were analyzed using FTIR, DLS, FE-SEM, AFM, 1H NMR, and 13CNMR analyses. Surface morphology revealed that the nanoparticles were homogenized and spherical with an average diameter of 25.5 nm. The chemical structure of the nanoparticles was similar to that of the microparticles. On the other hand, the chemical structure of acetylated lignin-sulfonate was slightly different from that of unmodified samples. The results also showed that the production of nano-lignin-sulfonate increased the acetylation efficiency and reduced the time and temperature of acetylation.


Assuntos
Acetilação/efeitos dos fármacos , Plásticos Biodegradáveis/química , Emulsões/química , Lignina/química , Nanopartículas/química , Ácidos Sulfônicos/química , Tamanho da Partícula , Temperatura , Águas Residuárias/química
7.
Int J Biol Macromol ; 154: 1366-1374, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31730982

RESUMO

The ß-glucosidase (BGL) enzyme in food industry is great interest due to its role in food conversion to produce functional food products. In this study, the BGL was covalently immobilized onto amino-tannic acid modified Fe3O4 magnetic nanoparticles (ATA-Fe3O4 MNPs) as biocompatible nanoplatform by modified poly-aldehyde pullulan (PAP) as a cross-linker to enhance the ability and strength of the nanoparticle connection to the enzyme. The properties of support were subsequently characterized by dynamic light scattering (DLS), transmission electron microscopy (TEM), Fourier transformed infrared (FTIR), X-ray diffraction (XRD), and vibrating sample magnetometer (VSM). The highest percentage of loading and immobilization yield was obtained with 0.1 mg enzyme/mL citrate buffer (pH 6, 1 M) enzyme solution, carrier solution of 10 mg ATA-Fe3O4/3 mL citrate buffer (pH 6, 1 M), and PAP solution of 20% total reaction system volume. Optimum pH and temperature were found for free (pH 5.0 and temperature 30 °C) and immobilized (pH 6.0 and temperature 40 °C) enzyme. The immobilized BGL maintains its activity to 83% after 10 cycles. Therefore, immobilization of BGL by this method is an efficient procedure to improve the properties of enzyme.


Assuntos
Enzimas Imobilizadas/química , Imãs/química , Nanopartículas/química , Taninos/química , beta-Glucosidase/química , Enzimas Imobilizadas/metabolismo , Química Verde , beta-Glucosidase/metabolismo
8.
Microb Pathog ; 131: 246-253, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30974159

RESUMO

Gastrointestinal (GI) infection is one of the most common types of infectious diseases. Application of probiotic strains in the control of such infections represents a promising approach. In this study, Lactobacillus fermentum strain 4-17 was isolated from kashkineh, an Iranian cereal fermented food, and identified by sequencing its 16S rRNA gene using universal primers. Its probiotic features, including resistance to acid, bile tolerance, antibacterial activity, resistance to intestinal and gastric juices, and hydrophobicity were evaluated. The ability of this strain to adhere to human intestinal cells as well as the anti-adhesive effect of L. fermentum strain 4-17 against E. coli isolated from patients with urinary tract infection was investigated. L. fermentum strain 4-17 was capable of surviving at various conditions such as low pH values, bile salts exposure, and GI tract environment. It showed 43% cell hydrophobicity. The adhesion level of L. fermentum strain 4-17 to human colon adenocarcinoma Caco-2 cells was 8.5% which was also confirmed by scanning electron microscopy (SEM). Furthermore, this strain showed appropriate anti-adhesive properties (including competition, inhibition and replacement properties) against human pathogenic bacteria. These data suggest that L. fermentum strain 4-17 could be examined further for its useful effects and introduced as a novel candidate probiotic to control GI infection disease.


Assuntos
Anti-Infecciosos/farmacologia , Aderência Bacteriana , Escherichia coli/efeitos dos fármacos , Limosilactobacillus fermentum/fisiologia , Probióticos/farmacologia , Infecções Urinárias/tratamento farmacológico , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Ácidos e Sais Biliares , Células CACO-2 , Escherichia coli/patogenicidade , Alimentos Fermentados/microbiologia , Suco Gástrico , Humanos , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Irã (Geográfico) , Limosilactobacillus fermentum/genética , Limosilactobacillus fermentum/isolamento & purificação , Probióticos/uso terapêutico , RNA Ribossômico 16S/genética , Tolerância ao Sal , Infecções Urinárias/microbiologia
9.
Radiol Med ; 124(1): 14-18, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30191446

RESUMO

INTRODUCTION: Regarding the increasing risk of violence toward employees in diagnostic and therapeutic centers, radiology staff members are often exposed to forms of violence through direct contact with patients and with many professional stresses. The aim of this study is to investigate the causes and incidence of violence against radiographers in radiology departments of educational centers and hospitals. MATERIALS AND METHODS: In this descriptive-analytic study, violence incidence was investigated in all 121 radiographers working in radiology departments of educational centers of Kermanshah in 2016. Data were collected by a reliable and stable researcher-made questionnaire. Data analysis was also performed using descriptive statistics and T test and Chi-square tests by STATA 11 software. RESULTS: The results showed that 72.7% of radiographers had experienced violence in their work environment. Verbal violence (77.3%) was the most prevalent type where patient accompaniments were the most frequent cause of violence (54.7%), most of the violence incidents were at night shift (43.6%) and over-crowdedness was the most common cause of violence in the radiology department (21.0%). The verbal violence against radiographers younger than 40 was significantly higher (P = 0.04) than the age group above 40 years. CONCLUSION: The incidence of verbal violence against radiographers in radiology departments is high which can be reduced by providing adequate human resource and equipment in radiology departments, re-training courses on the prevention and management of violent behavior and the suing the violent events against radiologists.


Assuntos
Amigos , Exposição Ocupacional/estatística & dados numéricos , Pacientes , Relações Profissional-Paciente , Serviço Hospitalar de Radiologia , Violência/estatística & dados numéricos , Centros Médicos Acadêmicos , Adulto , Aglomeração , Feminino , Humanos , Incidência , Irã (Geográfico)/epidemiologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Inquéritos e Questionários
10.
Artigo em Inglês | MEDLINE | ID: mdl-27812292

RESUMO

The 21st century is challenging for human beings. Increased population growth, population aging, generation of new infectious agents, and natural disasters are some threatening factors for the current state of blood transfusion. However, it seems that science and technology not only could overcome these challenges but also would turn many human dreams to reality in this regard. Scientists believe that one of the future evolutionary innovations could be artificial blood substitutes that might pave the way to a new era in transfusion medicine. In this review, recent status and progresses in artificial blood substitutes, focusing on red blood cells substitutes, are summarized. In addition, steps taken toward the development of artificial blood technology and some of their promises and hurdles will be highlighted. However, it must be noted that artificial blood is still at the preliminary stages of development, and to fulfill this dream, ie, to routinely transfuse artificial blood into human vessels, we still have to strengthen our knowledge and be patient.

11.
Microb Pathog ; 101: 36-43, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27816679

RESUMO

In this study, the screening of lipase positive bacteria from rice flour was carried out by Rhodamin B agar plate method. Bacillus cereus was identified by 16S rDNA method. Screening of the appropriate variables and optimization of the lipase production was performed using Plackett-Burman design (PBD) and response surface methodology (RSM). Among the isolated bacteria, an aerobic Bacillus cereus strain was recognized as the best lipase-producing bacteria (177.3 ± 20 U/ml). Given the results, the optimal enzyme production conditions were achieved with coriander seed extract (CSE)/yeast extract ratio of 16.9 w/w, olive oil (OO) and MgCl2 concentration of 2.37 g/L and 24.23 mM, respectively. In these conditions, the lipase activity (LA) was predicted 343 U/mL that was approximately close to the predicted value (324 U/mL), which was increased 1.83 fold LA compared with the non-optimized lipase. The kinetic parameters of Vmax and Km for the lipase were measured 0.367 µM/min.mL and 5.3 mM, respectively. The lipase producing Bacillus cereus was isolated and RSM was used for the optimization of enzyme production. The CSE/yeast extract ratio of 16.9 w/w, OO concentration of 2.37 g/L and MgCl2 concentration of 24.23 mM, were found to be the optimal conditions of the enzyme production process. LA at optimal enzyme production conditions was observed 1.83 times more than the non-optimal conditions. Ultimately, it can be concluded that the isolated B. cereus from rice flour is a proper source of lipase.


Assuntos
Bacillus cereus/enzimologia , Lipase/metabolismo , Aerobiose , Bacillus cereus/classificação , Bacillus cereus/crescimento & desenvolvimento , Bacillus cereus/isolamento & purificação , Técnicas Bacteriológicas , Meios de Cultura/química , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Farinha/microbiologia , Cinética , Programas de Rastreamento , Oryza/microbiologia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
12.
J Food Sci ; 81(7): H1833-9, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27273124

RESUMO

Quince fruit has many benefits to human health and is excellent source of bioactive compounds. The fruit of 15 quince genotypes stored at 2 °C for 5 mo to study fruit quality changes during cold storage. Fruit were sampled monthly and stored at 20 °C for 24 h. Fruit ascorbic acid (AA), total phenol (TP), and total flavonoid (TF) concentrations, total antioxidant activity (TAA), flesh browning (FB) incidence, polyphenol oxidase (PPO), peroxidase (POX), and superoxide dismutase (SOD) activities were measured during storage. A high variation in bioactive compounds was observed across genotypes. The range of 26.8 to 44.4 mg/100 g FW for AA, 86.7% to 98.2% for TAA, 157.7 to 380.7 mg GAE 100(-1) g FW for TP, and 5.3 to 10.7 mg/100 g FW for TF were observed across genotypes at harvest time. The overall AA, TAA, TP, TF, and SOD decreased while PPO and POX increased during storage. FB was first observed after 4 mo and increased thereafter while the FB index was different across genotypes. Higher bioactive content may prevent or reduce FB index so that a negative correlation was found between FB and AA, TAA, TP, TF, and SOD.


Assuntos
Antioxidantes/farmacologia , Temperatura Baixa , Armazenamento de Alimentos/métodos , Frutas/química , Extratos Vegetais/farmacologia , Rosaceae/química , Antioxidantes/análise , Ácido Ascórbico/análise , Ácido Ascórbico/farmacologia , Catecol Oxidase/metabolismo , Flavonoides/análise , Flavonoides/farmacologia , Genótipo , Humanos , Oxirredução , Fenóis/análise , Fenóis/farmacologia , Extratos Vegetais/análise , Rosaceae/genética , Superóxido Dismutase/metabolismo
13.
Food Chem ; 205: 257-63, 2016 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-27006238

RESUMO

Internal browning (IB) is a disorder in pears that is frequently observed in some cultivars. The present research was carried out to study biochemical changes and IB disorder of pear fruit during storage and ripening. Eight pear cultivars harvested and stored at 1°C up to 90 days. IB incidence, some bioactive compounds, polyphenol oxidase (PPO), peroxidase (POX), and superoxide dismutase (SOD) enzymes activities were measured during storage. IB increased during storage time but the susceptibility of cultivars was different. The ascorbic acid (AA), antioxidant capacity (AC) and SOD activity decreased while POX activity increased during storage but the rate of changes were different in studied cultivars. Total phenol (TP) and total flavonoid (TF) average content varied among pear cultivars and the highest TP and TF were observed in 'Bakhi' cultivars during storage. Fruit IB had positive correlation with the PPO activity, but negative correlation with TP, AC and AA.


Assuntos
Frutas/química , Fenóis/análise , Pyrus/química , Catecol Oxidase/análise , Armazenamento de Alimentos
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