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1.
Carbohydr Polym ; 297: 120030, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36184143

RESUMO

One of the most studied biocomponents is cellulose and its derivatives. Chemical structures of the nanocomposite films were investigated by Fourier Transform Infrared Spectroscopy (FT-IR) and X-Ray Diffraction (XRD) analyses. In the Scanning Electron Microscope (SEM) images taken at 5000 x magnification, the films with the best dispersion of nano-reinforcements; are amine modified nano SiO2 doped 2-hydroxyethyl cellulose (2-HEC) and hydroxypropyl cellulose (HPC) films. SiO2 dispersion has not been homogeneous in neutral nano SiO2 doped HPC and hydroxypropyl methylcellulose (HPMC) films. On the other hand, in the amine modified nano SiO2 doped HPMC film, micron-size agglomerations were observed on the film surface. When the thermal resistance of the films was examined, it was determined that the amine modified nano SiO2 doped HPMC film was the highest at 344 °C. When stress-strain values were compared, amine modified nano SiO2 doped HPMC film was the best film sample with a strain value of 101.7 %.


Assuntos
Celulose , Nanocompostos , Aminas , Celulose/química , Derivados da Hipromelose/química , Dióxido de Silício , Espectroscopia de Infravermelho com Transformada de Fourier
2.
Front Plant Sci ; 12: 736614, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34777419

RESUMO

Boron (B) is an important micronutrient required for the normal growth and development of plants. However, its excess in the soil causes severe damage to plant tissues, which affects the final yield. Wheat, one of the main staple crops, has been reported to be largely affected by B toxicity stress in arid and semi-arid regions of the world. The prevalence of B toxicity stress can be addressed by utilizing wild wheat genotypes with a variant level of stress tolerance. Wild wheat relatives have been identified as a prominent source of several abiotic stress-tolerant genes. However, Aegilops species in the tertiary gene pool of wheat have not been well exploited as a source of B toxicity tolerance. This study explores the root and shoot growth, proline induction, and extent of lipid peroxidation in 19 Aegilops accessions comprising 6 different species and the B-tolerant check wheat cultivar Bolal 2973 grown under Control (3.1 µM B), toxic (1 mM B), and highly toxic (10 mM B) B stress treatment. B toxicity stress had a more decisive impact on growth parameters as compared to the malondialdehyde (MDA) and proline content. The obtained results suggested that even the genotypes with high shoot B (SB) accumulation can be tolerant to B toxicity stress, and the mechanism of B redistribution in leaves should be studied in detail. It has been proposed that the studied Aegilops accessions can be potentially used for genetically improving the B toxicity-tolerance trait due to a high level of variation in the response toward high B toxicity. Though a number of accessions showed suppression in the root and shoot growth, very few accessions with stress adaptive plasticity to B toxicity stress leading to an improvement of shoot growth parameters could be determined. The two accessions, Aegilops biuncialis accession TGB 026219 and Aegilops columnaris accession TGB 000107, were identified as the potential genotypes with B toxicity stress tolerance and can be utilized for developing a pre-breeding material in B tolerance-based breeding programs.

3.
Clinics (Sao Paulo) ; 71(4): 221-5, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27166773

RESUMO

OBJECTIVE: This study was performed to evaluate the effects of metabolic parameters and thyroid dysfunction on the development of non-alcoholic fatty liver disease (NAFLD). METHODS: The current study evaluated a total of 115 patients, 75 female and 40 male. Physical examination and anthropometric measurements were applied to all participants. Hypothyroidism was considered at a thyroid stimulating hormone level ≥ 4.1 mIU/L. Patients with euthyroidism and patients with hypothyroidism were compared. Abdominal ultrasonography was used to diagnose non-alcoholic fatty liver disease. The participants were further compared with regard to the presence of non-alcoholic fatty liver disease. Logistic regression modeling was performed to identify the relationship between non-alcoholic fatty liver disease and independent variables, such as metabolic parameters and insulin resistance. RESULTS: Non-alcoholic fatty liver disease was identified in 69 patients. The mean waist circumference, body mass index, fasting plasma insulin, HOMA-IR (p<0.001) and FT3/FT4 ratio (p=0.01) values were significantly higher in the patients with NAFLD compared to those without it. Multivariate regression analysis revealed that FT3/FT4 ratio, waist circumference and insulin resistance were independent risk factors for non-alcoholic fatty liver disease. CONCLUSION: Insulin resistance, enlarged waist circumference, elevated body mass index, higher FT3/FT4 ratio and hypertriglyceridemia are independent risk factors for NADLF, whereas hypothyroidism is not directly related to the condition.


Assuntos
Hipotireoidismo/complicações , Hepatopatia Gordurosa não Alcoólica/etiologia , Glândula Tireoide/fisiopatologia , Tiroxina/sangue , Tri-Iodotironina/sangue , Adulto , Biomarcadores/sangue , Colesterol/sangue , Feminino , Humanos , Resistência à Insulina , Masculino , Síndrome Metabólica/complicações , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/sangue , Hepatopatia Gordurosa não Alcoólica/diagnóstico por imagem , Hepatopatia Gordurosa não Alcoólica/fisiopatologia , Obesidade/complicações , Análise de Regressão , Fatores de Risco , Triglicerídeos/sangue , Circunferência da Cintura
4.
Clinics ; 71(4): 221-225, Apr. 2016. tab
Artigo em Inglês | LILACS | ID: lil-781424

RESUMO

OBJECTIVE: This study was performed to evaluate the effects of metabolic parameters and thyroid dysfunction on the development of non-alcoholic fatty liver disease (NAFLD). METHODS: The current study evaluated a total of 115 patients, 75 female and 40 male. Physical examination and anthropometric measurements were applied to all participants. Hypothyroidism was considered at a thyroid stimulating hormone level ≥ 4.1 mIU/L. Patients with euthyroidism and patients with hypothyroidism were compared. Abdominal ultrasonography was used to diagnose non-alcoholic fatty liver disease. The participants were further compared with regard to the presence of non-alcoholic fatty liver disease. Logistic regression modeling was performed to identify the relationship between non-alcoholic fatty liver disease and independent variables, such as metabolic parameters and insulin resistance. RESULTS: Non-alcoholic fatty liver disease was identified in 69 patients. The mean waist circumference, body mass index, fasting plasma insulin, HOMA-IR (p<0.001) and FT3/FT4 ratio (p=0.01) values were significantly higher in the patients with NAFLD compared to those without it. Multivariate regression analysis revealed that FT3/FT4 ratio, waist circumference and insulin resistance were independent risk factors for non-alcoholic fatty liver disease. CONCLUSION: Insulin resistance, enlarged waist circumference, elevated body mass index, higher FT3/FT4 ratio and hypertriglyceridemia are independent risk factors for NADLF, whereas hypothyroidism is not directly related to the condition.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Hipotireoidismo/complicações , Hepatopatia Gordurosa não Alcoólica/etiologia , Glândula Tireoide/fisiopatologia , Tiroxina/sangue , Tri-Iodotironina/sangue , Biomarcadores/sangue , Colesterol/sangue , Resistência à Insulina , Síndrome Metabólica/complicações , Hepatopatia Gordurosa não Alcoólica/sangue , Hepatopatia Gordurosa não Alcoólica/diagnóstico por imagem , Hepatopatia Gordurosa não Alcoólica/fisiopatologia , Obesidade/complicações , Análise de Regressão , Fatores de Risco , Triglicerídeos/sangue , Circunferência da Cintura
5.
Carbohydr Polym ; 133: 624-36, 2015 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-26344321

RESUMO

This work presents a new approach to fabricating novel polymer nanofiber composites (NFCs) from water solution blends of PVA (hydrolyzed 89%)/ODA-MMT and Na-CMC/ODA-MMT nanocomposites as well as their folic acid (FA) incorporated modifications (NC-3-FA and NC-4-FA) through green electrospinning nanotechnology. The chemical and physical structures and surface morphology of the nanofiber composites were confirmed. Significant improvements in nanofiber morphology and size distribution of the NFC-3-FA and NFC-4-FA nanofibers with lower average means 110 and 113nm compared with those of NFC-1/NFC-2 nanofibers (270 and 323nm) were observed. The structural elements of polymer NFCs, particularly loaded partner NC-2, plays an important role in chemical and physical interfacial interactions, phase separation processing and enables the formation of nanofibers with unique morphology and excellent conductivity (NFC-3-FA 3.25×10(-9)S/cm and NFC-4-FA 8.33×10(-4)S/cm). This is attributed to the higher surface contact areas and multifunctional self-assembled supramacromolecular nanostructures of amorphous colloidal electrolytes. The anticancer activity of FA-containing nanofibers against osteocarcinoma cells were evaluated by cytotoxicity, apoptotic and necrotic analysis methods.


Assuntos
Neoplasias Ósseas/patologia , Carboidratos/química , Carboidratos/farmacologia , Condutividade Elétrica , Eletrólitos/química , Nanofibras/química , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Coloides , Humanos , Nanocompostos/química , Álcool de Polivinil/química , Propriedades de Superfície
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