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1.
Food Chem ; 305: 125458, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31505416

RESUMO

The purpose of the present study was to elucidate the effects of feeding flaxseed meal (FSM) and turmeric rhizome powder (TRP) supplementation on tissue lipid profile, lipid metabolism, health indices, oxidative stability, and physical properties of broiler chicken meat. The 100 g FSM along with 10.0 g TRP supplementation significantly increased the ω-3 PUFA, particularly ALA, EPA, DPA, and DHA of broiler chicken meat due to the corresponding increase ∆9 and Δ5 + Δ6 desaturase activities. The increased activities of the desaturases resulted in significantly better health indices of the broiler chicken meat. The feeding of 100 g FSM along with 10.0 g TRP supplementation reduced the atherogenic and thrombogenic indices of broiler chicken meat. The 100 g FSM feeding reduced the oxidative stability, water holding capacity, extract release volume of broiler chicken meat and increased drip loss, whereas, 10.0 g TRP supplementation reversed these negative effects of FSM.

2.
Artigo em Inglês | MEDLINE | ID: mdl-31701396

RESUMO

A feeding trial of 10 weeks duration was undertaken on laying hens (n = 240) to evaluate feeding value of rice distiller's dried grains with soluble (rDDGS) with or without enzyme supplementation (α-amylase, ß-glucanase, xylanase, carboxymethylcellulase, pectinase, proteinase, α-galactosidase, ß-galactosidase, lipase, and phytase), following 4 × 2 factorial design, on egg production, nutrient utilization, and cost economics of egg production. The birds were randomly assigned to eight dietary treatments with 30 birds/treatment. The birds were housed individually in layer cages and each bird was taken as an experimental unit. Eight experimental diets were prepared by incorporating four levels (0, 50, 75, and 100 g/kg) of rDDGS with and without enzyme supplementation. The results revealed a significant (P < 0.01) increase of egg mass, feed intake, egg production, and body weight gain in dietary treatments with up to 75 g rDDGS though the values were statistically similar to the hens fed 100 g rDDGS. Enzyme supplementation resulted in significant (P < 0.01) improvement of egg mass, egg production, feed conversion ratio (FCR) per dozen eggs, FCR per kilogramme egg mass, and net FCR. The significantly (P < 0.01) higher yolk index was observed at 100 g rDDGS level, while shell thickness improved significantly (P < 0.01) up to 75 g rDDGS level. No significant effect of rDDGS inclusion was observed on shape index, albumin index, and Haugh unit. Enzyme supplementation significantly improved the shell thickness and yolk colour of eggs. Nitrogen, calcium, and phosphorus retention and dry matter metabolizability did not show any significant treatment effects. There was significant (P < 0.01) reduction in feed-cost per kilogramme egg mass or per dozen eggs with the increased DDGS levels and dietary enzyme supplementation. It was concluded that rDDGS can be used up to 100 g/kg diet of laying hens along with enzyme supplementation for better productivity of layer hens.

3.
J Anim Physiol Anim Nutr (Berl) ; 102(2): e957-e963, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29352493

RESUMO

Two hundred turkey breeder hens and 24 viable toms of 30-35 weeks age of small white variety were distributed into two treatment groups having four replicates of 25 hens and three toms in each treatment. First four replicates were offered a turkey breeder diet (Diet A) (Nutrient requirements of poultry, 1994, National Academic Press, Washington, DC) and the rest four replicates were maintained on a higher plane of nutrition (Diet B) for 8-week duration. After 6 weeks of experimental feeding, two replicates from each treatment groups were vaccinated with ND (R2 B) vaccine. Yolk sac of embryo from birds fed Diet B had a significantly higher (p < .05) IgG, IgM level and HI titre (log 2) than those fed Diet A. HI titre values of embryonic yolk sac from the vaccinated birds fed Diet B were significantly higher (p < .05) than that of the control groups. In addition, HI titre values were significantly higher (p < .05) in the day-old poults of the birds fed Diet B than that of those fed Diet A. There was significantly (p < .01) positive correlation between serum IgG and IgM of the breeder birds and day-old chicks. Similarly, there was significantly (p < .05) positive correlation between yolk IgG and IgM after 1-month experimental feeding and yolk sac IgG and IgM. Positive correlation (p < .05) also existed between yolk sac IgM and day-old chick serum IgM. Furthermore, the HI titres of breeder birds' serum at 14 days post-vaccination were positively correlated with their egg yolk after 10 and 15 days post-vaccination, yolk sac and day-old chicks. Thus, the study envisaged that a higher immunity in neonate poults from turkey breeders maintained on a higher plane of nutrition may be elicited as there was maternal transfer of antibodies from the serum of breeder birds to their offsprings through their yolk sac.


Assuntos
Ração Animal/análise , Dieta/veterinária , Gema de Ovo/química , Imunoglobulinas/química , Perus , Saco Vitelino/química , Fenômenos Fisiológicos da Nutrição Animal , Animais , Feminino , Imunoglobulinas/metabolismo , Masculino , Necessidades Nutricionais
4.
Phys Chem Chem Phys ; 19(47): 31747-31755, 2017 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-29167857

RESUMO

Subtle changes in the microstructure and dynamics of the triblock copolymer L121, (ethylene oxide)5 (propylene oxide)68 (ethylene oxide)5i.e., E5P68E5, and sodium dodecylsulfate (SDS) system in aqueous medium were investigated using high-resolution nuclear magnetic resonance (NMR), electron paramagnetic resonance (EPR) and small-angle neutron scattering (SANS) methods. NMR self-diffusion measurements helped us to understand the nature of binding of SDS with L121, and the formation of their mixed aggregates. These results showed that even at low [SDS] (∼2 mM), the addition of L121 stabilized the dynamics of SDS. Furthermore, the increase in [SDS] resulted in progressive changes in the diffusion behavior of both SDS and L121. 13C chemical shift analysis revealed that preferential binding of L121 occurred on the SDS micelle surface. Deuterium (2H) NMR spin-relaxation data evidenced that the formed mixed aggregates were non-spherical in terms of relaxation rate changes, and slowed the dynamics. The rotational correlation times of mixed aggregates were estimated from EPR analysis. A SANS study indicated the presence of uni- and multi-lamellar vesicles of L121 at low [SDS]. The vesicles transformed to mixed L121-SDS micelles in the presence of a higher [SDS]. This was supported by the measurements of 2H NMR spin-relaxation and EPR rotational correlation times.

5.
J Food Sci Technol ; 54(12): 3899-3907, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29085132

RESUMO

A total of 240 broiler chicken of same hatch with uniform weight were used in a biological experiment with completely randomized design to investigate the effects of incorporating organic chromium (Cr) in flaxseed meal based diet on the fatty acid profile, oxidative stability and functional properties of broiler chicken meat. Five diets were formulated as per the recommendations of BIS (Nutrient requirements for poultry 13: 9863, Bureau of Indian Standards, New Delhi, 1992) in which flaxseed meal was used to replace 10% of soyabean in basal diet and four levels of Cr (0.0, 0.5, 1.0 and 1.5 mg/kg diet) as Cr-picolinate were used. The results revealed that flaxseed feeding significantly increased the percentage of unsaturated fatty acids, including MUFA, PUFA, ω-3, ω-6 fatty acids and ω-3:ω-6 and PUFA:SFA ratios, whereas, significant decline was seen in saturated fatty acids and no effect of Cr was observed on the fatty acid profile of broiler chicken. Flaxseed feeding significantly reduced the cholesterol and fat percentage of meat, whereas, significant progressive reduction was observed with increasing Cr levels. The combination of 10% flaxseed with 1.0 mg Cr/kg diet increased the final pH of broiler meat. The addition of flaxseed significantly reduced water holding capacity, extract release volume and antioxidant potential of broiler meat, whereas, increasing Cr supplementation progressively increased them. Flaxseed feeding significantly increased the drip loss and lipid peroxidation of broiler meat, whereas, Cr supplementation decreased them. It was concluded that inclusion of 10% flaxseed and 1.5 mg Cr/kg diet results in desirable fatty acid profile, oxidative stability and functional properties of broiler chicken meat.

6.
J Anim Physiol Anim Nutr (Berl) ; 101(2): 229-235, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27486071

RESUMO

An attempt was made to investigate the effect of dietary selenium (Se) on physical and cloacal gland size, foam production, biochemical composition of foam and semen biochemical characteristics of male Japanese quail (Coturnix coturnix Japonica). Two hundred twenty-five (225)-day-old male Japanese quail were randomly distributed to three dietary treatment groups for a period of 20 weeks. Each treatment comprised of three replicates, each containing 25 chicks. Three experimental diets were supplemented with 0, 0.5 and 1.0 mg Se/kg (T1 , T2 and T3, respectively), and diet T1 was considered as control. Sodium selenite was used as the source of selenium. All the birds were provided with feed and water ad libitum. Cloacal foam characteristics, that is cloacal gland index and foam weight, were significantly higher in T2 group. However, body weight, frequency of foam discharge and testes weight (left and right) did not differ significantly (p > 0.05). Physical characteristics of semen, that is semen volume and sperm concentration, did not differ (p > 0.05) among the Se-treated groups. The sperm motility, live-dead count and abnormality improved significantly (p < 0.05) in 0.5 mg/Se-supplemented group compared to 0 or 1.0 mg/Se-supplemented groups. Similarly, fertility and hatchability percentages were higher (p < 0.05) in 0.5 mg/Se-supplemented group than in control or 1.0 mg/Se-supplemented counterparts. The biochemical characteristics of foam in terms of total protein, acid phosphatase (ACP) and nitric oxide did not differ (p > 0.05), while the concentration of glucose was higher (p < 0.05) in 0.5 mg/Se-supplemented diet. On the other hand, alkaline phosphatase (ALP), alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were lower (p < 0.05) in 0.5 mg/Se-supplemented group compared to control or 1.0 mg/Se-supplemented groups. From this study, it was concluded that supplementation of 0.5 mg Se/kg diet was beneficial for foam variables, biochemical composition of foam, semen characteristics and fertility in male Japanese quail.


Assuntos
Ração Animal/análise , Cloaca/fisiologia , Coturnix/fisiologia , Dieta/veterinária , Selênio/farmacologia , Sêmen/fisiologia , Fenômenos Fisiológicos da Nutrição Animal , Animais , Suplementos Nutricionais , Masculino , Selênio/administração & dosagem
7.
Phys Chem Chem Phys ; 18(31): 21251-8, 2016 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-27211796

RESUMO

Butterfly-shaped tetrabenzo[a,c,g,i]fluorene (TBF)-based molecules (1 and 2) were designed, synthesized and well characterized using various spectroscopic techniques. The single crystal X-ray structure of 1 shows the presence of intermolecular 3-D π-π stacking interaction and unprecedented "cold crystallization" in polycyclic aromatic molecules. We report for the first time, the "bottom-up" self-assembly of TBF based organic molecules. The supramolecular studies reveal the formation of vesicles and cuboid-shaped nanocrystals in THF-water and toluene solution, respectively.

8.
Phys Chem Chem Phys ; 17(45): 30560-9, 2015 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-26523917

RESUMO

The influence of the water soluble non-ionic tri-block copolymer PEO-PPO-PEO [poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide)] i.e., E2P16E2 (L31) on the microstructure and self-aggregation dynamics of the anionic surfactant sodium dodecylsulfate (SDS) in aqueous solution was investigated using cloud point (CP), isothermal titration calorimetry (ITC), high resolution nuclear magnetic resonance (NMR), electron paramagnetic resonance (EPR), and small-angle neutron scattering (SANS) measurements. CP provided the thermodynamic information on the Gibbs free energy, enthalpy, entropy and heat capacity changes pertaining to the phase separation of the system at elevated temperature. The ITC and NMR self-diffusion measurements helped to understand the nature of the binding isotherms of SDS in the presence of L31 in terms of the formation of mixed aggregates and free SDS micelles in solution. EPR analysis provided the micro-viscosity of the spin probe 5-DSA in terms of rotational correlation time. The SANS study indicated the presence of prolate ellipsoidal mixed aggregates, whose size increased with the increasing addition of L31. At a large [L31], SANS also revealed the progressive decreasing size of the ellipsoidal mixed aggregates of SDS-L31 into nearly globular forms with the increasing SDS addition. Wrapping of the spherical SDS micelles by L31 was also corroborated from (13)C NMR and SANS measurements.


Assuntos
Polietilenoglicóis/química , Propilenoglicóis/química , Dodecilsulfato de Sódio/química , Tensoativos/química , Química Física , Estrutura Molecular , Termodinâmica
9.
Phys Chem Chem Phys ; 17(30): 19936-47, 2015 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-26166360

RESUMO

2-Octyl thiophene based three-ring mesogens namely 4-n-alkoxyphenyl 4-(5-n-octyl-2-thienyl)benzoates are synthesized by employing palladium acetate based direct arylation. The alkoxy terminal is varied with even carbons from C2 to C14 and enantiotropic polymesomorphism is noticed for all the homologs. Accordingly, phase sequence consisting of nematic, smectic A, smectic C and smectic B is seen for mesogens with terminal chains C6, C8, C10 and C12 on cooling the isotropic phase. For mesogens with C2, C4, C8 and C10 terminal alkoxy chains, the mesophase assignment from hot-stage optical microscopy and differential scanning calorimetry is further confirmed by variable temperature powder X-ray diffraction measurements. The appearance of smectic B phase is established by noticing sharp and intense peaks in both small-angle and wide-angle regions. For a representative mesogen, i.e. T10, high-resolution solid-state (13)C NMR investigations are carried out in all the phases, viz. nematic, smectic A, smectic C and smectic B phases. The orientational order parameters calculated from (13)C-(1)H dipolar couplings from 2D SAMPI-4 experiments are found to be 0.44, 0.67, 0.73 and 0.79 in nematic, smectic A, smectic C and smectic B mesophases for the center phenyl ring respectively. Remarkably, the thiophene order parameter in all mesophases is found to be higher than that of phenyl rings and is explained by considering the molecular shape, which has a terminal bend. Further, the mesogens are found to be photoemissive in chloroform solution with an emission band at ∼410 nm.

10.
Radiat Prot Dosimetry ; 163(1): 14-21, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24743763

RESUMO

Lithium tetraborate doped with manganese synthesised by solid-state sintering technique exhibits a dosimetric peak at 280°C. The high-temperature glow curve results in no fading for three months. The sensitivity of Li2B4O7:Mn is determined to be 0.9 times that of TLD-100. The infrared spectrum of this phosphor indicates the presence of bond vibrations corresponding to BO4 tetrahedral and BO3 triangles. The mechanism for thermoluminescence in this phosphor was proposed based on the thermoluminescence (TL) emission spectra, kinetic analysis of TL glow curves and electron paramagnetic resonance (EPR) measurements on non-irradiated and gamma-irradiated phosphors. It was identified that oxygen vacancies and Boron oxygen hole centre (BOHC) are the electron and hole trap centres for TL in this phosphor. When the phosphor is heated, the electrons are released from the electron trap and recombine with the trapped holes. The excitation energy during the recombination is transferred to the nearby Mn(2+) ions, which emit light at 580 nm.


Assuntos
Boratos , Lítio , Manganês , Dosimetria Termoluminescente/métodos , Boratos/química , Boratos/efeitos da radiação , Espectroscopia de Ressonância de Spin Eletrônica , Raios gama , Humanos , Lítio/química , Lítio/efeitos da radiação , Medições Luminescentes/métodos , Manganês/química , Manganês/efeitos da radiação , Espectrofotometria Infravermelho
11.
J Anim Physiol Anim Nutr (Berl) ; 99(1): 163-173, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24797673

RESUMO

A study was undertaken to investigate the role of in ovo administrated carbohydrates on the expression pattern of growth and immune-related genes. In ovo injections (n = 400) were carried out on the 14th day of incubation into the yolk sac/amnion of the broiler chicken embryos. Expression of growth-related genes: chicken growth hormone (cGH), insulin-like growth factor-I & II (IGF-I & II) and mucin were studied in hepatic and jejunum tissues of late-term embryo and early post-hatch chicks. Expression of candidate immune genes: Interleukin-2, 6, 10 and 12 (IL-2, IL-6, IL-10 and IL-12), Tumour necrosis factor-alpha (TNF-α) and Interferon gamma (IFN-γ) were studied in peripheral blood monocyte cells of in ovo-injected and control birds following antigenic stimulation with sheep RBC (SRBC) or mitogen concanavalin A (Con-A). Glucose injection significantly increased the expression of IGF-II gene during embryonic period and both cGH and IGF-II in early post-hatch period, while ribose-injected chicks had higher expression of IGF-II gene during embryonic stage. Enhanced mucin gene expression was also observed in fructose-injected chicks during embryonic age. Glucose-injected chicks had higher expression of IL-6 or IL-10, while those injected with fructose or ribose had higher expression of IL-2, IL-12 and IFN gamma. It is concluded that in ovo supplementation of carbohydrates might help in improving the growth of late-term embryos and chicks. In ovo glucose could modulate humoral-related immunity, while fructose or ribose might help in improving the cellular immunity in broiler chickens.


Assuntos
Carboidratos/farmacologia , Galinhas/crescimento & desenvolvimento , Galinhas/imunologia , Regulação da Expressão Gênica/efeitos dos fármacos , Animais , Carboidratos/administração & dosagem , Embrião de Galinha , Regulação da Expressão Gênica/imunologia , Óvulo
12.
Anim Reprod Sci ; 151(3-4): 237-43, 2014 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-25458321

RESUMO

This experiment investigated the effect of dietary chromium (Cr as picolinate) on physical and biochemical characteristics of semen and carcass traits of adult male turkey. Seventy-two (72) male turkeys (16 weeks old) were randomly distributed into four dietary treatment groups (4×3×6) for a period of 24 weeks. Three experimental diets were supplemented with 250, 500 and 750µg Cr/kg (T2, T3 and T4 respectively) in basal diet (T1 considered as control). Semen physical characteristics viz. sperm concentration, progressive motility, live and dead count of spermatozoa and fertility differed significantly (P<0.05). Sperm concentration, progressive motility and fertility were higher and dead count was lower in T4 (750µg) group than control (T1) or other dietary treatments (T2 or T3) group. Semen biochemical parameters like creatinine, acid phosphatase (ACP) and alkaline phosphatase (ALP) concentration did not differ significantly among the dietary treatment groups, whereas, total protein, glucose, malondialdehyde (MAD) and cholesterol concentration differed significantly (P<0.05) amongst the treatment groups. Protein and MAD were higher while glucose and cholesterol concentrations were lower in T3 and T4 group than control or T1 group. The shrinkage loss, eviscerated yield, relative weight (as percent of body weight) of breast, thigh and liver improved on supplementation of Cr leading to significantly higher in T4 group in comparison to control. From this study, it could be concluded that supplementation of chromium as chromium picolinate, at 750µg/kg level in diet was beneficial for improving physical characteristics of semen, carcass yield and breast yield of adult male turkeys. However, Cr levels of 500 or 750µg/kg in diet were beneficial for semen biochemical parameters of adult male turkeys.


Assuntos
Constituição Corporal/efeitos dos fármacos , Cromo/administração & dosagem , Suplementos Nutricionais , Ácidos Picolínicos/administração & dosagem , Sêmen/efeitos dos fármacos , Perus , Ração Animal , Animais , Biomarcadores/análise , Peso Corporal/efeitos dos fármacos , Fertilidade/efeitos dos fármacos , Masculino , Sêmen/química , Sêmen/fisiologia , Análise do Sêmen
13.
Ecotoxicol Environ Saf ; 108: 152-60, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25062447

RESUMO

Silver nanoparticles (AgNPs) pose a high risk of exposure to the natural environment owing to their extensive usage in various consumer products. In the present study we attempted to understand the harmful effect of AgNPs at environmentally relevant low concentration levels (≤1ppm) towards two different freshwater bacterial isolates and their consortium. The standard plate count assay suggested that the AgNPs were toxic towards the fresh water bacterial isolates as well as the consortium, though toxicity was significantly reduced for the cells in the consortium. The oxidative stress assessment and membrane permeability studies corroborated with the toxicity data. The detailed electron microscopic studies suggested the cell degrading potential of the AgNPs, and the FT-IR studies confirmed the involvement of the surface groups in the toxic effects. No significant ion leaching from the AgNPs was observed at the applied concentration levels signifying the dominant role of the particle size, and size distribution in bacterial toxicity. The reduced toxicity for the cells in the consortium than the individual isolates has major significance in further studies on the ecotoxicity of the AgNPs.


Assuntos
Nanopartículas Metálicas/toxicidade , Consórcios Microbianos/efeitos dos fármacos , Prata/toxicidade , Permeabilidade da Membrana Celular/efeitos dos fármacos , Água Doce/microbiologia , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Estresse Oxidativo/efeitos dos fármacos , Tamanho da Partícula , Espectroscopia de Infravermelho com Transformada de Fourier , Testes de Toxicidade
14.
Soft Matter ; 10(31): 5682-94, 2014 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-24983665

RESUMO

The detailed aggregation behavior of sodiumdodecyl sulfate (SDS) in tetrahydrofuran (Tf)-water (W) and formamide (Fa)-water (W) media at varied volume percent compositions has been investigated. Surface tension (ST), conductance (Cond), viscosity (Visc), isothermal titration calorimetry (ITC), nuclear magnetic resonance (NMR) and small angle neutron scattering (SANS) were used in this study. The presence of nonaqueous solvents affected the critical micelle concentration (CMC) of SDS, the counter-ion binding of the micelle, the energetics of the air/water interfacial adsorption and micellization of the amphiphiles in the bulk, the ion-association (ion-pair, triple-ion, quadruple, etc. between Na(+) and DS(-) ions) as well as the weakly soluble (aggregation less) amphiphile solution. Tf has been observed to produce a "dead zone" or "non-micelle formation zone" in the mixed Tf-W domain of 10-40 vol%. Fa influenced the SDS aggregation up to 70 vol%, at higher proportions (below the Krafft temperature (K(T))), instead of the micelle, "randomly arranged globular assembly" (RAGA) was formed. The correlation of the standard free energy of micellization (ΔG(m)(0)) with different solvent parameters (1) dielectric constant (ε), (2) viscosity (η0), (3) Reichardt parameter (E(T)(30)), (4) Gordon parameter (G), and (5) Hansen-Hildebrand hydrogen bonding parameter (δ(h)) has been attempted. It has been found that δ(h) produced a master correlation between ΔG(m)(0) and δ(h) for different binary mixtures such as Tf-W, Fa-W, Ml-W and Dn-W.

15.
J Biomed Nanotechnol ; 10(3): 508-18, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24730246

RESUMO

The purpose of this study was to evaluate the in vitro macrophage compatibility, the inflammatory response and in vivo host response to a novel collagen-chitosan (COL-CS) scaffold containing growth factors incorporated Chitosan Nanoparticle (CNP). The scaffold was obtained by freezing a blend of COL-CS solution and growth factor incorporated CNP followed by lyophilization. High Resolution Transmission Electron Micrograph (HR-TEM) indicated that growth factors incorporated CNP were in the size range of 50-100 nm, while Scanning Electron Microscopic (SEM) analysis of the scaffold surface suggests that the pores of the scaffolds (COL-CS) were well interconnected, with a mean diameter of 75-150 microm. Macrophages grown on growth factors containing scaffold exhibited poor inflammatory response compared to scaffold without growth factors. In vivo biocompatibility and host response study of scaffold was performed by subcutaneous implantation and examination of the implanted material on day 3 and 15 post implant. The dual growth factors viz. EGF (Epidermal Growth Factor) and FGF (Fibroblast Growth Factor) incorporated implant showed a distinct fibrous capsule boundary on the surface. Secondly, the immunofluoresence assay and zymography respectively for TNFalpha and MMP9 exhibited low expression of these inflammatory markers. These observations divulge that the growth factors when incorporated, can suppress the inflammatory properties of the scaffolds and thus such scaffolds could be used in tissue engineering for minimal host response and enhanced tissue-scaffold interaction.


Assuntos
Quitosana/química , Colágeno/química , Peptídeos e Proteínas de Sinalização Intercelular/administração & dosagem , Macrófagos/efeitos dos fármacos , Nanopartículas/efeitos adversos , Próteses e Implantes/efeitos adversos , Tecidos Suporte/efeitos adversos , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Quitosana/efeitos adversos , Colágeno/efeitos adversos , Reação a Corpo Estranho/induzido quimicamente , Reação a Corpo Estranho/prevenção & controle , Peptídeos e Proteínas de Sinalização Intercelular/química , Peptídeos e Proteínas de Sinalização Intercelular/farmacocinética , Macrófagos/citologia , Macrófagos/fisiologia , Teste de Materiais , Camundongos , Camundongos Endogâmicos BALB C , Nanopartículas/química , Tecidos Suporte/química
16.
Aquat Toxicol ; 138-139: 1-11, 2013 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-23680676

RESUMO

In the current study, two aspects concerning (i) the cytotoxicity potential of TiO2 nanoparticles (NPs) toward freshwater algal isolate Scenedesmus obliquus and (ii) the potential detoxification of NPs by the microalgae were assessed under light (UV-illumination) and dark conditions at low exposure levels (≤1 µg/mL), using sterile freshwater as the test medium. The statistically significant reduction in cell viability, increase in reactive oxygen species production and membrane permeability (light vs. dark) suggested photo-induced toxicity of TiO2 NPs. The electron micrographs demonstrated adsorption of the NPs onto the cell surface and substantiated their internalization/uptake. The fluorescence micrographs and the confocal laser scanning (CLSM) images suggested the absence of a definite/intact nucleus in the light treated cells pointing toward the probable genotoxic effects of NPs. In a separate three cycle experiment, a continuous decrease in the cytotoxicity was observed, whereas, at the end of each cycle only fresh algae were added to the supernatant containing NPs from the previous cycle. The decreasing concentrations of the NPs in the subsequent cycles owing to agglomeration-sedimentation processes exacerbated by the algal interactions played a crucial role in the detoxification. In addition, the exo-polymeric substances produced by the cells could have rendered the available NPs less reactive, thereby, enhancing the detoxification effects.


Assuntos
Poluentes Ambientais/toxicidade , Nanopartículas Metálicas/toxicidade , Scenedesmus/efeitos dos fármacos , Titânio/toxicidade , Adsorção , Biodegradação Ambiental , Contagem de Células , Permeabilidade da Membrana Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Água Doce , Nanopartículas Metálicas/ultraestrutura , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Espécies Reativas de Oxigênio/metabolismo , Scenedesmus/ultraestrutura , Sais de Tetrazólio , Tiazóis , Testes de Toxicidade , Raios Ultravioleta
17.
J Phys Chem B ; 117(18): 5718-29, 2013 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-23627902

RESUMO

Structural characterizations using XRD and (13)C NMR spectroscopy of two rodlike mesogens consisting of (i) three phenyl ring core with a polar cyano terminal and (ii) four phenyl ring core with flexible dodecyl terminal chain are presented. The three-ring-core mesogen with cyano terminal exhibits enantiotropic smectic A phase while the four-ring mesogen reveals polymesomorphism and shows enantiotropic nematic, smectic C, and tilted hexatic phases. The molecular organization in the three-ring mesogen is found to be partial bilayer smectic Ad type, and the interdigitation of the molecules in the neighboring layers is attributed to the presence of the polar terminal group. For the four-ring mesogen, the XRD results confirm the existence of the smectic C and the tilted hexatic mesophases. A thermal variation of the layer spacing across the smectic C phase followed by a discrete jump at the transition to the tilted hexatic phase is also observed. The tilt angles have been estimated to be about 45° in the smectic C phase and about 40° in tilted hexatic phase. (13)C NMR results indicate that in the mesophase the molecules are aligned parallel to the magnetic field. From the (13)C-(1)H dipolar couplings determined from the 2D experiments, the overall order parameter for the three-ring mesogen in its smectic A phase has been estimated to be 0.72 while values ranging from 0.88 to 0.44 have been obtained for the four-ring mesogen as it passes from the tilted hexatic to the nematic phase. The orientations of the different rings of the core unit with respect to each other and also with respect to the long axis of the molecule have also been obtained.


Assuntos
Compostos de Bifenilo/química , Cristais Líquidos/química , Nitrilos/química , Compostos de Bifenilo/síntese química , Isótopos de Carbono , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Nitrilos/síntese química , Teoria Quântica , Difração de Raios X
18.
Langmuir ; 29(23): 6805-14, 2013 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-23718941

RESUMO

Polymer nanoparticle coated micelle assemblies of lauryl ester of tyrosine (LET) act as potential nanocarriers for the model solid lipid stearyl alcohol. The coating is afforded by a simple methodology of heterophase polymerization reaction of styrene or the mixture of styrene and butyl acrylate at a mole ratio of 0.8:0.2 in the presence of 200 mM LET in water. On the contrary, the polymer nanoparticles produced under similar conditions in the presence of a structurally similar surfactant, lauryl ester of phenyl alanine (LEP), failed to act as nanocarrier. The micelle templates of LET and LEP favored polymerization under controlled conditions as observed from the near monodisperse distribution of molecular weight and size of the polymers. The particle size distribution of poly(styrene) (PS) and poly(styrene-co-butyl acryalte) (PS-co-PBA) nanoparticles from LET was smaller at 24 and 20 nm in comparison to those from LEP. The encapsulation efficiency of polymer nanoparticles from LET surfactant is explained on the basis of difference in the coating of micelle assemblies, which we believe must be arising due to difference in the solubilization site of the monomers in the surfactant micelles before polymerization reaction. The solubilization of the model monomer, benzene at different regions, varying between shell and core of LET and LEP micelles is established from (1)H nuclear magnetic resonance spectra. The evidence for the coating of micelle assemblies from surface tension measurements and the encapsulation of stearyl alcohol in the polymer nanoparticle dispersions from LET drawn from transmission electron microscopy, differential scanning calorimetry, and thermogravimetric analysis is discussed.


Assuntos
Aminoácidos/química , Lipídeos/química , Nanoestruturas/química , Polímeros/química , Tensoativos/química , Micelas , Tamanho da Partícula , Polímeros/síntese química , Propriedades de Superfície
19.
Langmuir ; 29(19): 5734-41, 2013 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-23590729

RESUMO

Sodium salts of maleamic acid derivatives of lauryl ester of tyrosine (MTNa) and phenyl alanine (MPNa) in water exhibited strong pH-responsive behaviors of viscosity and specific conductivity that originate from the concentration and pH dependence of their aggregation states. The aggregates were characterized by a novel spin-probe-partitioning electron paramagnetic resonance (SPPEPR) method and dynamic light scattering (DLS). Results of high-precision fitting of the second-harmonic EPR spectra of the small spin probe di-tert-butyl nitroxide (DTBN) in these aggregates together with viscosity, conductivity, and DLS showed that, at pH ~ 7.54, MTNa formed micelles and MPNa vesicles and MTNa exhibited a pH-induced micelle to vesicle transition as pH was lowered toward 6. MTNa, at pH ~ 7.54, formed small micelles at low concentrations that transformed to long worm-like micelles for concentrations ≥ 0.05 M, accompanied by a 30-fold increase in solution viscosity. The hydrodynamic radii from DLS confirmed the presence of small micellar aggregates of radius ~ 2 nm in MTNa at pH ~ 7.54 at the lower concentrations, with coexisting micelles (~2 nm) and vesicles (~50 nm) at pH near 6.5, vesicles (radii ~ 70 nm) at pH near 6, and large vesicles (85 nm) in MPNa at pH ~ 7.60. Both MTNa and MPNa precipitated upon reduction of pH below 6 and below 7, respectively. The rate of transfer of DTBN between the aqueous phase and the aggregate was calculated from the high-field Lorentzian linewidths of the electron paramagnetic resonance (EPR) spectra. The activation energy for the transfer determined from the temperature dependence of the rate of transfer is 12.7 kJ/mol for MTNa vesicles (pH ~ 6) and 20.6 ± 1.3 kJ/mol for MPNa (pH ~ 7.60). The pH-induced transformations were reversible.


Assuntos
Fenilalanina/química , Tensoativos/química , Tirosina/química , Água/química , Concentração de Íons de Hidrogênio , Modelos Moleculares , Estrutura Molecular , Tamanho da Partícula , Polimerização , Propriedades de Superfície
20.
J Phys Chem A ; 117(18): 3791-7, 2013 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-23574486

RESUMO

Transmission electron microscopy (TEM) images and fluorescence quenching methods indicated that lauryl ester of L-phenylalanine (LEP) and lauryl ester of L-tyrosine (LET) form spherical chiral micelles in the 50-200 mM range and their size increases with concentration. The number of molecules present in these spherical chiral aggregates varied from 80 to 160 for LEP and 80-100 for LET. The specific optical rotation, representing circular birefringence, for LEP at 405 nm and 32 °C is found to increase linearly from 37 deg cc g(-1) dm(-1) for an isolated molecule to 56 deg cc g(-1) dm(-1) for ∼200 nm size aggregate. A similar trend was found for temperatures up to 70 °C and at other visible wavelengths. A linear relation between specific optical rotation and the size of aggregate is also observed for LET. Circular dichroism, as measured in both the visible and infrared wavelength regions, however did not reveal any concentration dependent changes. The unique sensitivity uncovered for specific optical rotation as a function of the size of spherical chiral aggregates is unprecedented and opens new areas of enquiry for physical chemists.

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