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1.
Front Plant Sci ; 12: 625541, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33679838

RESUMEN

Water-deficit stress negatively affects seed germination, seedling development, and plant growth by disrupting cellular and metabolic functions, reducing the productivity and yield of field crops. In this study, sodium silicate (SS) has been employed as a seed priming agent for acclimation to mild water-deficit stress by invoking priming memory in wheat plants. In pot experiments, the SS-primed (20, 40, and 60 mM) and non-primed control seeds were allowed to grow under normal and mild water-deficit conditions. Subsequently, known methods were followed for physiological and biochemical studies using flag leaves of 98-day mature wheat plants. The antioxidant and hydrolytic enzymes were upregulated, while proteins, reducing sugars, total sugars, and glycine betaine increased significantly in the flag leaves of wheat plants originated from SS-treated seeds compared to the control under mild water-deficit stress. Significant decreases in the malondialdehyde (MDA) and proline contents suggested a controlled production of reactive oxygen species, which resulted in enhanced cell membrane stability. The SS priming induced a significant enhancement in yield, plant biomass, and 100-grain weight of wheat plants under water-deficit stress. The improvement in the yield parameters indicated the induction of Si-mediated stress acclimation in SS-primed seeds that elicited water-deficit tolerance until the maturity of plants, ensuring sustainable productivity of climate-smart plants.

2.
Plant Physiol Biochem ; 160: 329-340, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33548800

RESUMEN

AIM: Water-deficit stress is the most devastating environmental factor that adversely affects plant growth causing yield losses and low crop productivity. In this study, we employed sodium nitroprusside (SNP) as a seed priming agent for the acclimation of water-deficit stress in wheat plants by invoking priming memory. METHODS: The SNP-primed (75, 100, and 125 µM) and non-primed controls were allowed to grow in pots under water deficit and normal conditions. The flag leaves of 98-days mature plants were used for biochemical and physiological studies by following the well-established methods. RESULTS: The antioxidant and hydrolytic enzymes were upregulated while reducing sugars, total sugars, and glycine betaine increased significantly in flag leaves of wheat plants originated from SNP-treated seeds compared to control under water deficit stress. However, a significant reduction in MDA and proline contents represented a lesser ROS production which resulted in enhanced cell membrane stability. Consequently, there was a significant enhancement in yield, plant biomass and 100 grains weight of wheat plants under water deficit stress. CONCLUSION: The improvement in yield parameters indicates the induction of priming memory in SNP-primed seeds which elicit water deficit tolerance till the maturity of plants thus ensures sustainable productivity of wheat.


Asunto(s)
Aclimatación , Sequías , Nitroprusiato/farmacología , Triticum/efectos de los fármacos , Triticum/fisiología , Agua/fisiología
3.
J Ayub Med Coll Abbottabad ; 26(3): 310-5, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25671935

RESUMEN

BACKGROUND: Although new Pegylated Interferon is available, yet the conventional Interferon with the combination of Ribavirin is still the therapy of choice to treat the Hepatitis C patients. This study was conducted to investigate the response of different HCV genotypes in different age groups of chronic Hepatitis C patients treated with conventional Interferonα-2b (IFNα-2b) plus Ribavirin (RBV). METHODS: In this cross sectional observational study a total of 520 Hepatitis C patients infected with different HCV genotypes meeting the study criteria were included from August 2010 to January 2013. End of treatment response (ETR), sustained virological response (SVR) and the association of patient's age with treatment response were evaluated. ETR and SVR were defined as absence of HCV RNA and normal ALT level at the end of therapy and 12 months after the termination of therapy respectively. RESULTS: Out of 520 cases 388 (74.62%) showed ETR. The SVR was observed in 290 (89.23%) out of 325 ETR responders. ETR was higher in males (76.14%) than females (72.77%) while the SVR was almost same in both sex. The highest ETR was noted in genotype 3 (81.15%). The old patients exhibited lower ETR and SVR than youngers in the present study. CONCLUSIONS: The properly managed conventional Interferon therapy was effective for Hepatitis C patients infected with genotype 2 and 3 with age <40 years as compared to those patients infected with genotype-1 and 4 or had age >40 years.


Asunto(s)
Antivirales/uso terapéutico , Hepacivirus/efectos de los fármacos , Hepacivirus/genética , Hepatitis C Crónica/tratamiento farmacológico , Interferón-alfa/uso terapéutico , Polietilenglicoles/uso terapéutico , Adolescente , Adulto , Factores de Edad , Niño , Estudios Transversales , Quimioterapia Combinada , Femenino , Genotipo , Hepatitis C Crónica/virología , Humanos , Interferón alfa-2 , Masculino , Persona de Mediana Edad , Proteínas Recombinantes/uso terapéutico , Ribavirina/uso terapéutico , Factores Sexuales , Adulto Joven
4.
J Pak Med Assoc ; 62(10): 1033-8, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23866441

RESUMEN

OBJECTIVE: To observe the antiglycation effect of water-soluble vitamin, thiamin-hydrochloride (B1) and its fat-soluble derivative benfotiamine and their comparison with two different glycation assays in diabetics. METHODS: Plasma of both the normal's and diabetic persons was taken for this experimental study which was conducted in the Department of Chemistry and Biochemistry, University of Agriculture, Faisalabad in 2008. Varying concentrations of both the glycation inhibitors and glucose were incubated for 5 weeks at 37 degrees C. Thiobarbituric acid and periodate borohydride assays were used to measure the antiglycation activity. RESULTS: The increase in glycation was observed from 1st to 3rd week of incubation, while it decreased after the 5th week due to the formation of advanced glycation end products. CONCLUSIONS: It was observed that 10mM concentration of benfotiamine and 5mM and 1mM concentrations of thiamine-hydrochloride produced fairly good response to decreased glycation. Comparison between two assays proved periodate borohydride to be more reliable and sensitive than thiobarbituric acid.


Asunto(s)
Glucemia/efectos de los fármacos , Glucemia/metabolismo , Quelantes/farmacología , Diabetes Mellitus/metabolismo , Tiamina/análogos & derivados , Tiamina/farmacología , Complejo Vitamínico B/farmacología , Relación Dosis-Respuesta a Droga , Productos Finales de Glicación Avanzada/análisis , Glicosilación/efectos de los fármacos , Humanos
5.
Braz. j. pharm. sci ; 48(4): 601-607, Oct.-Dec. 2012. ilus, tab
Artículo en Inglés | LILACS | ID: lil-665856

RESUMEN

Aqueous extracts of Zingiber officinale rhizomes were studied to evaluate their antidiabetic effects on protein glycation and on the diffusion of glucose in vitro in the present study. Zingiber officinale rhizome aqueous extract were examined at concentrations of 5, 10, 20 and 40 g/L. The antidiabetic effects were found to be dose-dependent. Antidiabetic potential of Zingiber officinale was mainly through inhibition of the glucose diffusion and to a limited extent by reducing the glycation. However, further studies are needed to determine in vitro effects of therapeutic potential by restraining postprandial glucose absorptions and plasma protein glycations in diabetic subjects.


Extratos aquosos de rizomas Zingiber officinale foram estudados para avaliar os seus efeitos antidiabéticos em glicação de proteínas e sobre a difusão de glicose in vitro, no presente estudo. Extratos aquosos de Zingiber officinale foram examinados nas concentrações de 5, 10, 20 e 40 g extrato de planta/L. Os efeitos antidiabéticos observados eram dependentes da dose. O potencial antidiabético de Zingiber officinale se verificou, principalmente, através da inibição da difusão de glicose e, em menor extensão, através da redução da glicação. Estudos adicionais são necessários para elucidar se efeitos in vitro representam potencial terapêutico, restringindo a absorção de glicose pós-prandial e a glicação de proteínas plasmáticas em indivíduos diabéticos.


Asunto(s)
Técnicas In Vitro/clasificación , Zingiber officinale , Hipoglucemiantes/antagonistas & inhibidores , Farmacognosia/clasificación , Diabetes Mellitus , Glucosa/clasificación , Hiperglucemia
6.
Int J Biol Macromol ; 44(1): 23-8, 2009 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-19041889

RESUMEN

Chitin-based polyurethane elastomers having potential for biomedical applications with tunable mechanical properties were synthesized by step growth polymerization techniques using poly(epsilon-caprolactone) (PCL) with different diisocyanates. The prepolymer was extended using chitin and/or 1,4-butane diol (BDO). The structures of the resulted polymers were determined by Fourier transform infrared (FTIR), 1H NMR and 13C NMR spectroscopic techniques. The effect of structure of diisocyanates and chain extenders on mechanical properties and in vitro biocompatibility were investigated. The results revealed that the final polymers extended with chitin are preferred candidates for surgical threads with on going investigations into their in vitro biocompatibility and non-toxicity.


Asunto(s)
Elastómeros/química , Isocianatos/química , Poliuretanos/química , Suturas , Elastómeros/síntesis química , Ensayo de Materiales , Fenómenos Mecánicos , Resonancia Magnética Nuclear Biomolecular , Poliésteres , Poliuretanos/síntesis química , Espectroscopía Infrarroja por Transformada de Fourier
7.
Int J Biol Macromol ; 44(1): 18-22, 2009 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-18930759

RESUMEN

Chitin based polyurethane elastomers with potential as biomedical implants with tunable mechanical properties were synthesized by step growth polymerization techniques using poly(epsilon-caprolactone) (PCL) and 4,4'-diphenylmethane diisocyanate (MDI). The prepolymer was extended with different mass ratios of chitin and 1,4-butane diol (BDO). Molecular characterization was done using FTIR, 1H NMR and 13C NMR techniques. The mechanical properties of these polymers were improved with increase in the chitin contents. Optimum mechanical properties were obtained from elastomers extended with chitin in comparison to elastomers extended with BDO. Cytotoxicity of the synthesized polyurethane samples was affected by varying the chitin contents in the chemical composition of the final polyurethane (PU). It is revealed that the final polymers extended with chitin are preferred candidates for surgical threads with on going investigations into their in vitro biocompatibility and non-toxicity.


Asunto(s)
Butanos/química , Quitina/química , Elastómeros/química , Poliuretanos/química , Suturas , Elastómeros/síntesis química , Isocianatos , Ensayo de Materiales , Fenómenos Mecánicos , Resonancia Magnética Nuclear Biomolecular , Poliésteres , Poliuretanos/síntesis química , Espectroscopía Infrarroja por Transformada de Fourier
8.
Int J Biol Macromol ; 43(2): 136-41, 2008 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-18495239

RESUMEN

Chitin-based polyurethane elastomers (PUEs) were synthesized by step growth polymerization techniques using poly(epsilon-caprolactone) (PCL) varying diisocyanate and chain extender structures. The viscosity average molecular weight (M(v)) of chitin was deduced from the intrinsic viscosity and found; M(v)=6.067 x 10(5). The conventional spectroscopic characterization of the samples with FTIR, (1)H NMR and (13)C NMR were in accordance with proposed PUEs structure. The crystalline behavior of the synthesized polymers were investigated by X-ray diffraction (XRD), differential scanning calorimetery (DSC) and loss tangent curves (tan delta peaks). The observed patterns of the crystalline peaks for the lower angle for chitin in the 2theta range were indexed as 9.39 degrees, 19.72 degrees, 20.73 degrees, 23.41 degrees and 26.39 degrees. Results showed that crystallinity of the synthesized PUEs samples was affected by varying the structure of the diisocyanate and chain extender. Crystallinity decreased from aliphatic to aromatic characters of the diisocyanates used in the final PU. The presence of chitin also favors the formation of more ordered structure, as higher peak intensities was obtained from the PU extended with chitin than 1,4-butane diol (BDO). The value of peak enthalpy (DeltaH) of chitin was found to be 47.13 J g(-1). The higher DeltaH value of 46.35 J g(-1) was found in the samples extended with chitin than BDO (39.73 J g(-1)).


Asunto(s)
Quitina/química , Elastómeros/síntesis química , Poliuretanos/química , Elastómeros/química , Espectroscopía de Resonancia Magnética , Estructura Molecular , Poliésteres , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X
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