27 research outputs found

    The effect of climatic conditions on exercise-induced bronchoconstriction in 10-12 year old students

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    Exercise-induced asthma is seen following vigorous or prolonged exercise or physical exertion. It has been suggested that climatic conditions have an influence on exercise-induced asthma. Therefore, the aim of the present study was to examine the effect of two climatic conditions on exercise-induced deterioration of pulmonary function tests in 10-12 year old students.Two hundred and fifty six students were randomly chosen from two cities namely Kerman and Gorgan (128 subjects in each who were equally from both cities) including 62 girls and 66 boys of 10-12 years old. A questionnaire was used to obtain demographic information and to identify the prevalence of asthma symptoms. Each subject performed a seven-minute free run exercise with maximum effort and sufficient motivation until they reached 70-75% heart rate. Pulmonary function tests (PFT) including, forced vital capacity (FVC), forced expiratory volume in one second (FEV1), peak expiratory flow (PEF), and maximum expiratory flow at 50% of vital capacity (MEF50) were measured before, at the beginning, and 7 and 20 min after physical activity.The prevalence of both asthma (28.12%) and exercise-induced asthma (20.31%) in Kerman students was higher than those of Gorgan students (21.09% and 17%, respectively). All PFT values declined 7 and 20 min post-exercise in both groups. Although all baselines PFT in Kerman students were higher than those of Gorgan students, the decline in PFT values in Kerman students was greater than those of Gorgan students. At 20 min post exercise, the decline in FEV1, PEF and MEF50 in Kerman students was significantly higher than those of Gorgan students (p < 0.05 to p < 0.01).The results of the present study showed that prevalence of both asthma and exercise-induced asthma in a city with dry and cool climate such as Kerman was higher than in a city with humid climate such as Gorgan. In addition, the results showed that in a humid climate, post-exercise decline in PFT values was less than in a dry climate. © 2015 Elsevier Ltd

    Comparative emulsifying properties of octenyl succinic anhydride (OSA)-modified starch: Granular form vs dissolved state

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    The emulsifying ability of OSA-modified and native starch in the granular form, in the dissolved state and a combination of both was compared. This study aims to understand mixed systems of particles and dissolved starch with respect to what species dominates at droplet interfaces and how stability is affected by addition of one of the species to already formed emulsions. It was possible to create emulsions with OSA-modified starch isolated from Quinoa as sole emulsifier. Similar droplet sizes were obtained with emulsions prepared at 7% (w/w) oil content using OSA-modified starch in the granular form or molecularly dissolved but large differences were observed regarding stability. Pickering emulsions kept their droplet size constant after one month while emulsions formulated with OSA-modified starch dissolved exhibited coalescence. All emulsions stabilized combining OSA-modified starch in granular form and in solution showed larger mean droplet sizes with no significant differences with respect to the order of addition. These emulsions were unstable due to coalescence regarding presence of free oil. Similar results were obtained when emulsions were prepared by combining OSA-modified granules with native starch in solution. The degree of surface coverage of starch granules was much lower in presence of starch in solution which indicates that OSA-starch is more surface active in the dissolved state than in granular form, although it led to unstable systems compared to starch granule stabilized Pickering emulsions, which demonstrated to be extremely stable

    The Effect of Cardiac Rehabilitation on the Serum Levels of Adiponectin and Lipoproteins in Male Atherosclerotic Patients

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    Abstract: Background and Aims: Adiponectin is the most important and promising adipocytokine to understand the relationship of obesity, metabolic syndrome and cardiovascular diseases showing anti-diabetic, anti-inflammatory and anti atherosclerotic effects too. The aim of this research was to survey the effect of cardiac rehabilitation, via special aerobic exercise training, on the serum levels of adiponectin hormone and lipoprotein lipid profile in men with atherosclerosis. Methods: Twenty patients with atherosclerosis (40-65-year-old men), selected by convenience sampling method and normalized by exercise training and primary tests, were enrolled. During 8 weeks (three session per week), subjects had 30 to 45 minutes training sessions by using treadmill, ergo meter, and arm ergo meter with the intensity of 30-50 percent of heart rate reserve. The t-test was conducted to check the difference between pretest and posttest at the significant level of P≤0.05. Results: The level of adiponectin and HDL increased and the level of LDL, triglyceride and cholesterol decreased significantly. Conclusion: We concluded that cardiac rehabilitation has probably beneficial effects on the serum levels of adiponectin and lipoproteins in men with coronary artery disease after MI. Keywords: Cardiac rehabilitation, Adiponectin, Lipoprotein, Atherosclerotic patient

    Resveratrol loaded Pickering emulsions stabilized by OSA modified rice starch granules

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    Resveratrol is a photosensitive, bioactive molecule which has received increasing research interest during the past decade for its antioxidant properties. However, it has low solubility in water or common triglyceride oils. Resveratrol solubilization in oil can only be achieved in essential oils, such as flavour oils, but the stability of emulsions produced with this type of oils is low as they are prone to creaming phenomena and Oswald ripening. In this study, resveratrol was first dissolved in orange oil which was mixed into a medium-chain triglyceride (Miglyol) at different ratios and used as the internal phase of oil-in-water emulsions (O/W). The emulsions were stabilized by octenyl succinic anhydride (OSA) modified rice starch granules using two different ratios of starch particle:oil to study the influence of interfacial coverage on the final emulsion droplet size and emulsion stability. The results of this study indicated that stable Pickering emulsions could be prepared using OSA-modified rice starch granules even at partial coverage conditions. Emulsions prepared at an oil fraction of 0.5 using 30% v/v mixture of orange oil in Miglyol as the dispersed phase seemed to be an appropriate resveratrol carrier system, obtaining encapsulation efficiency values close to 90% which results in emulsions with a resveratrol concentration of 8.45 mg/L. Hence, the emulsions prepared are suitable for food fortification applications

    Characterization and stability of short-chain fatty acids modified starch Pickering emulsions

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    Acetylated, propionylated and butyrylated rice and quinoa starches at different levels of modification and starch concentrations, were used to stabilize oil-in-water starch Pickering emulsions at 10% oil fraction. Short-chain fatty acid modified starch Pickering emulsions (SPEs) were characterized after emulsification and after 50 days of storage. The particle size distribution, microstructure, emulsion index, and stability were evaluated. An increase in starch concentration led to a decrease of emulsion droplet sizes. Quinoa starch has shown the capability of stabilizing Pickering emulsions in both the native and modified forms. The emulsifying capacity of SPEs was improved by increasing the chain length of SCFA. Modified quinoa starch with higher chain lengths (i.e. propionylated and butyrylated), at higher levels of modification, showed higher emulsion index (>71%) and stability over the entire 50 days storage. At optimized formulation, SCFA-starch particles have the potential in stabilizing emulsions for functional foods, pharmaceutical formulations, or industrial food applications

    Pickering emulsifiers based on hydrophobically modified small granular starches Part II – Effects of modification on emulsifying capacity

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    Small granular starches from rice, quinoa, and amaranth were modified with octenyl succinic anhydride (OSA) at 5 defined intervals (0–3.0%) and investigated with respect to emulsifying capacity and stability. Starch granule surfaces were characterized by Brunauer–Emmett–Teller and contact angle measurements. Emulsifying capacity was characterized by multiple light scattering (MLS) and particle size analysis. Stability towards environmental stress was characterized by centrifugation and MLS. Surface hydrophobicity and emulsifying capacity correlated with starch type and modification level. Quinoa stabilized emulsions had the smallest droplet size (e.g. 59.2 μm at 3.0% OSA) and superior stability, both before and after centrifugation, especially at the lowest modification levels. Rice and amaranth had larger droplets (99.8 and 84.1 μm at 3.0% OSA respectively). Amaranth, despite its small size showed poorer performance than quinoa, especially at lower modification levels. The higher emulsifying efficiency of quinoa starch granules attributed to the higher protein content

    Synthesis of controlled size starch nanoparticles (SNPs)

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    Starch nanoparticles (SNPs) are a promising choice for the strategic development of new renewable and biodegradable nanomaterials for novel biomedical and pharmaceutical applications when loaded with antibiotics or with anticancer agents as target drug delivery systems. The final properties of the SNPs are strongly influenced by the synthesis method and conditions being a controlled and monodispersed size crucial for these applications. The aim of this work was to synthesize controlled size SNPs through nanoprecipitation and microemulsion methods by modifying main operating parameters regarding the effect of amylose and amylopectin ratio in maize starches. SNPs were characterized by size and shape. SNPs from 59 to 118 nm were obtained by the nanoprecipitation method, registering the higer values when surfactant was added to the aqueous phase. Microemulsion method led to 35−147 nm sizes observing a higher particle formation capacity. The composition of the maize used influenced the final particle size and shape

    Pickering emulsifiers based on hydrophobically modified small granular starches – Part I : Manufacturing and physico-chemical characterization

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    Small granular starches from rice, quinoa and amaranth were hydrophobized by esterification with octenyl succinic anhydride (OSA) in an aqueous alkaline slurry to obtain series of modified starches at defined intervals (i.e. 0.6, 1.2, 1.8, 2.4, 3.0%). The physical and the physico-chemical properties of the starch particles were characterized by proximate analysis including protein level, amylose level and dry matter. The shape and size of the starch granules were characterized by scanning electron microscopy and light scattering. The gelatinization properties were characterized by differential scanning calorimetry. The degree of modification was determined by titration with NaOH. With regard to the emulsion formulation and in order to assess the emulsifying capacity of the small granular starches, the effect of starch type, degree of modification and starch concentration on the resulting emulsion droplet size were evaluated by light scattering and optical microscopy. Emulsifying properties were found to depend on the degree of substitution, size of the granules and the starch to oil ratio of the formulation. Quinoa starch granules, in general, had the best emulsifying capacity followed by amaranth and rice. However, in higher starch concentrations (>400 mg/mL oil) and adequate levels of OSA (3.0%) amaranth performed best, having the smallest size of starches studied
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