44 research outputs found

    Optimization of silk yarn hierarchical structure by genetic algorithm to design scaffolds

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    A genetic algorithm model has been developed to determine the optimal parameters of mechanical aspects of a silk wire-rope scaffold with the highest predictive accuracy and generalized ability simultaneously. The study pioneered on employing a genetic algorithm (GA) to optimize the parameters of scaffold in tendon and ligament tissue engineering. Experimental results show that the GA model performs the best predictive accuracy to imply mechanical behavior with native values successfully

    Effectiveness of Parents-Focused Cognitive-Behavioral Therapy on Attention Deficit Hyperactivity Disorder Symptoms, Obesity and Self-Esteem of Overweight Children with Attention Deficient Hyperactivity Disorder

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    Background: Attention deficit hyperactivity disorder (ADHD) is the most common behavioral problems that cause hyperactivity, attention deficits, academic failure, and emotional and behavioral problems in preschool and elementary school that is often hidden from the parents' eyes. The aim of this study was to determine the effectiveness of parent-based cognitive-behavioral therapy (CBT) on ADHD symptoms (including attention deficit disorder, restlessness, and impulsivity), overweight and self-esteem of 6–11-year-old obese children with attention deficit hyperactivity in Isfahan. Materials and Methods: This quasi-experimental study was carried out on 40 children aged 6–11 years with ADHD and overweight or obesity (above the 85th percentile in weight for age, height, and sex diagram) that their parents referred to Isfahan child and adolescent psychiatric clinic of Ali Asghar Hospital in 2015. For twenty patients, only ADHD treatment was applied, and they received no other intervention, but the others in experimental group participated in CBT sessions. Analysis tools were Coppersmith Self-Esteem Scale, ADHD conners' test, and the body mass index (BMI). Data were analyzed using analysis of variance with repeated measurements. Results: CBT by teaching parents had a significant effect on ADHD symptoms, the self-esteem of overweight and obese children with ADHD in posttest and follow-up. The results also showed that had a significant effect on ADHD symptoms, overweight and self-esteem of the obese children with ADHD (P < 0.001). Conclusions: Parents focused CBT can be considered as a complementary treatment for reducing ADHD symptoms and BMI and increased self-esteem in the obese ADHD children

    Optimization of silk yarn hierarchical structure by genetic algorithm to design scaffolds

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    81-86A genetic algorithm model has been developed to determine the optimal parameters of mechanical aspects of a silk wire-rope scaffold with the highest predictive accuracy and generalized ability simultaneously. The study pioneered on employing a genetic algorithm (GA) to optimize the parameters of scaffold in tendon and ligament tissue engineering. Experimental results show that the GA model performs the best predictive accuracy to imply mechanical behavior with native values successfully

    Evaluate the growth and adhesion of osteoblast cells on nanocomposite scaffold of hydroxyapatite/titania coated with poly hydroxybutyrate

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    Background: The generation of bioartificial bone tissues may help to overcome the problems related to donor site morbidity and size limitations. Materials and Methods: In this paper, hydroxyapatite (HA) powder was made out of bovine bone by thermal analysis at 900°C and first, and then, porous HA (50 weight percentage) was produced by polyurethane sponge replication method. In order to improve the scaffold mechanical properties, they have been coated with poly hydroxybutyrate. In terms of phase studies, morphology, and specifying agent groups, the specific characterization devices such as X-ray diffraction and Fourier transform infrared, were employed. To compare the behavior of cellular scaffolds, they were divided into four groups of scaffolds. The osteoblast cells were cultured. To perform phase studies, analysis of Methylthiazole tetrazolium (MTT) and Trypan blue were carried out for the viability and attachment on the surface of the scaffold, and the specification of Scanning electron microscopy was employed for the morphology of the cells. Results: The results of MTT analysis performed on four groups of scaffolds have shown that Titanium oxide (Tio2 ) had no effect on cell growth alone and HA was the main factor of growth and cell osteoblast adhesion on the scaffold. Moreover, the results showed that the use of coating with poly-3-hydroxybutyrate saved the factors and placed the osteoblasts within the pore. Since the main part of bone consists of HA, the TiO2 accelerates the formation of apatite crystals at the scaffold surface which is the evidence for bone tissue regeneration. Conclusions: It is likely that the relation between HA and TiO2 leads to an increase in osteoblast adhesion and growth of cells on the scaffold surface

    Preparing nanocomposite fibrous scaffolds of P3HB/nHA for bone tissue engineering

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    Nanocomposites are recently known to be among the most successful materials in biomedical applications. In this work we sought to fabricate fibrous scaffolds which can mimic the extra cellular matrix of cartilaginous connective tissue not only to a structural extent but with a mechanical and biological analogy. Poly(3-hydroxybutyrate) (P3HB) matrices were reinforced with 5, 10 and 15 %wt hydroxyapatite (HA) nanoparticles and electrospun into nanocomposite fibrous scaffolds. Mechanical properties of each case were compared with that of a P3HB scaffold produced in the same processing condition. Spectroscopic and morphological observations were used for detecting the interaction quality between the constituents. Nanoparticles rested deep within the fibers of 1 μm in diameter. Chemical interactions of hydrogen bonds linked the constituents through the interface. Maximum elastic modulus and mechanical strength was obtained with the presence of 5%wt hydroxyapatite nanoparticles. Above 10%wt, nanoparticles tended to agglomerate and caused the entity to lose its mechanical performance; however, viscoelasticity interfered at this concentration and lead to a delayed failure. In other words, higher elongation at break and a massive work of rupture was observed at 10%wt

    Extremely low-frequency electromagnetic field influences the survival and proliferation effect of human adipose derived stem cells

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    Background: Extremely low-frequency electromagnetic fields (ELF-EMF) can effect on biological systems and alters some cell functions like proliferation rate. Therefore, we aimed to attempt the evaluation effect of ELF-EMF on the growth of human adipose derived stem cells (hADSCs). Materials and Methods: ELF-EMF was generated by a system including autotransformer, multi-meter, solenoid coils, teslameter and its probe. We assessed the effect of ELF-EMF with intensity of 0.5 and 1 mT and power line frequency 50 Hz on the survival of hADSCs for 20 and 40 min/day for 7 days by MTT assay. One-way analysis of variance was used to assessment the significant differences in groups. Results: ELF-EMF has maximum effect with intensity of 1 mT for 20 min/day on proliferation of hADSCs. The survival and proliferation effect (PE) in all exposure groups were significantly higher than that in sham groups (P < 0.05) except in group of 1 mT and 40 min/day. Conclusion: Our results show that between 0.5 m and 1 mT ELF-EMF could be enhances survival and PE of hADSCs conserving the duration of exposure

    Clinical associations between renal dysfunction and vascular events: A literature review

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    Chronic kidney disease affects several other organs of the human body, and causes high levels of morbidity and mortality due to these effects. The cardiovascular system is probably the most vulnerable organ to a decrease in kidney function, and responds very fast to this effect. To the extent that, more kidney disease patients die of cardiovascular events than that of the original renal disease. Moreover, cerebrovascular events have been confirmed to increase, and to have inferior outcomes on the general population. In this review article, we aim to review studies investigating effects of renal disease on vascular events. Keywords: Renal Disease, Cardiovascular Disorders, Dialysis, Myocardial Infarction, Risk Factor </p

    Pediatric patients with renal disease and cardiovascular complications: A literature review

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    The cardiovascular burden of end stage renal disease (ESRD) in children has recently received more attention, and some authors have recommended that the origins of the increase in cardiovascular morbidity and mortality be found in childhood. In this comprehensive review of the literature, we aim to review the main and most recent studies evaluating cardiovascular risk factors in pediatric kidney disease patients. The literature suggests that ESRD, even in the pediatric population, is associated with a high rate of cardiovascular morbidity and mortality, and needs serious attention. Unfortunately, there is extreme scarcity of data on the efficacy of preventive strategies on cardiovascular morbidity and mortality in pediatric patients with renal disease. Therefore, authors of the current article recommend future studies to be directed to find beneficial and/or potential harmful effects of different interventions conventionally used in this population, including lifestyle modifications and pharmaceutical therapy on cardiovascular indices. Moreover, the effects of these drugs on the renal function of children with minimal kidney disease should be evaluated. &nbsp; Keywords: Cardiovascular Complication, Children, Kidney Disease, Pediatrics&nbsp;</pre
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