257 research outputs found

    Radial polynomials as alternatives to smooth radial basis functions and their applications

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    Because of the high approximation power and simplicity of computation of smooth radial basis functions (RBFs), in recent decades they have received much attention for function approximation. These RBFs contain a shape parameter that regulates the relation between their accuracy and stability. A difficulty in approximation via smooth RBFs is optimal selection of shape parameter. The aim of this paper is to introduce an alternative for smooth RBFs, which in addition to overcoming this difficulty, its approximation power is almost equal to RBFs...

    Medicinal herbs in the treatment of neuropathic pain: a review

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    Chronic neuropathic pain is a common significant and debilitating problem that presents a major challenge to health-care. Despite the large number of available drugs, there are no curative conventional treatments for neuropathic pain. Nowadays, more attention has been focused on the herbal formulation in the field of drug discovery. Therefore, we performed an extensive review about herbal drugs and plants that exhibited protective effects on neuropathic pain. In this review, the beneficial effects of each plant in different neuropathic pain model, either in animals or in patients are reported. Moreover, the possible involved mechanisms for the protective effects are discussed. The more common plants which are used for the treatment of neuropathic pain are included as: Acorus calamus, Artemisia dracunculus, Butea monosperma, Citrullus colocynthis, Curcuma longa, Crocus sativus, Elaeagnus angustifolia, Ginkgo biloba, Mitragyna speciosa, Momordica charantia, Nigella sativa, Ocimum sanctum, Phyllanthus amarus, Pterodon pubescens Benth, Rubia cordifolia and Salvia officinalis. Furthermore, the most pathways which are known to be involved in pain relief by means of herbal remedies are anti-oxidant activity, anti-inflammatory, anti-apoptotic, neuroprotective and calcium inhibitory actions.In conclusion, this review suggests that some herbal plants can be suitable candidates for the treatment of neuropathic pain

    The effect of melatonin on aerobic capacity and time of exhaustion during a sub-maximum activity in girl students of physical education

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    Background: Preservation and storage of muscle glycogen is the most important factor limiting the success of individuals in performing the following activities. It has been shown that melatonin supplementation before exercise can maintain glycogen stores. This study aimed to investigate the effect of melatonin consumption (6 mg) on the time of exhaustion during a submaximal-activity and also the maximum oxygen consumption during an increasing activity in physical education girl students of Shahid Chamran University of Ahvaz. Materials and Methods: In this clinical trial study, 13 girls with the mean age of 21.5±1.29 years, the mean weight of 58.36±2.69 kg and vo2max 39.08±4.17 mg/kg/min were participated and received melatonin (6 mg) and placebo (starch capsules) in two complementary steps. Supplements were administered acutely 30 minutes before the exercise. Each test was repeated in placebo and supplement conditions. To ensure the elimination of exercise and supplement impact, the interval of 5 to 7 days was considered between the two tests. The sub-maximal and progressive protocols respectively included running below the maximum intensity (70 of the heart rate reserve) to exhaustion and the Bruce's test on the treadmill. Results: The results showed that consumption of 6 mg melatonin significantly increased the time to reach exhaustion (P=0.01) and the maximum oxygen consumption (P=0.002). Conclusion: It appears that trained girls can use 6 mg of melatonin supplement 30 minutes before starting the exercise to improve endurance performance and aerobic capacity

    A brief report on the relationship between self-control, video game addiction and academic achievement in normal and ADHD students

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    Background and aims: Over the last two decades, research into video game addiction has grown increasingly. The present research aimed to examine the relationship between video game addiction, self-control, and academic achievement of normal and ADHD high school students. Based on previous research it was hypothesized that there would be a relationship between video game addiction, self-control and academic achievement video game addiction, self-control and academic achievement would differ between male and female students, and the relationship between video game addiction, self-control and academic achievement would differ between normal students and ADHD students. Methods: The research population comprised first grade high school students of Khomeini-Shahr (a city in the central part of Iran). From this population, a sample group of 339 students participated in the study. The survey included the Game Addiction Scale (Lemmens, Valkenburg & Peter, 2009), the Self-Control Scale (Tangney, Baumeister & Boone, 2004) and the ADHD Diagnostic checklist (Kessler et al., 2007). In addition to questions relating to basic demographic information, students’ Grade Point Average (GPA) for two terms was used for measuring their academic achievement. These hypotheses were examined using a regression analysis. Results: Among Iranian students, the relationship between video game addiction, self-control, and academic achievement differed between male and female students. However, the relationship between video game addiction, self-control, academic achievement, and type of student was not statistically significant. Conclusions: Although the results cannot demonstrate a causal relationship between video game use, video game addiction, and academic achievement, they suggest that high involvement in playing video games leaves less time for engaging in academic work

    Chitosan–Pluronic nanoparticles as oral delivery of anticancer gemcitabine: preparation and in vitro study

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    Nanoparticles have proven to be an effective delivery system with few side effects for anticancer drugs. In this study, gemcitabine-loaded nanoparticles have been prepared by an ionic gelation method using chitosan and Pluronic® F-127 as a carrier. Prepared nanoparticles were characterized using dynamic light scattering, Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), scanning electron microscopy, and transmission electron microscopy. Different parameters such as concentration of sodium tripolyphosphate, chitosan, Pluronic, and drug on the properties of the prepared nanoparticles were evaluated. In vitro drug release was studied in phosphate-buffered saline (PBS; pH = 7.4). The cytotoxicity of the nanoparticles was assayed in the HT-29 colon cancer cell line. The mucoadhesion behavior of the nanoparticles was also studied by mucus glycoprotein assay. The prepared nanoparticles had a spherical shape with positive charge and a mean diameter ranging between 80 to 170 nm. FT-IR and DSC studies found that the drug was dispersed in its amorphous form due to its potent interaction with nanoparticle matrix. Maximum drug encapsulation efficiency was achieved at 0.4 mg/mL gemcitabine while maximum drug loading was 6% obtained from 0.6 mg/mL gemcitabine. An in vitro drug release study at 37°C in PBS (pH = 7.4) exhibited a controlled release profile for chitosan–Pluronic® F-127 nanoparticles. A cytotoxicity assay of gemcitabine-loaded nanoparticles showed an increase in the cytotoxicity of gemcitabine embedded in the nanoparticles in comparison with drug alone. The mucoadhesion study results suggest that nanoparticles could be considered as an efficient oral formulation for colon cancer treatment

    Nano drug delivery platform based on thermosensitive PEG-PCL hydrogel encapsulated in silver-bearing micelles and its antifungal activity investigation against vaginal candidiasis

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    Introduction: Vaginal candidiasis is a genital mucosal disease. Polymeric micelles (PMs) utilization due to improved solubility and low bioavailability of hydrophobic drugs e.g. clotrimazole is of interest. Silver nanoparticles could be applied to enhance antifungal properties. Loading PMs in injectable thermosensitive hydrogels by rapid distribution across vaginal walls improves the bioavailability of the drug and provides suitable therapeutic efficiency for drug delivery systems.Method: PCL-PEG-PCL (LGL) and PEG-PCL-PEG (GLG) copolymers were characterized by FTIR, HNMR, and GPC. Zeta potential and Size of synthesized PMs were determined by EMSA and DLS technics and morphological examination of PMs was conducted by FESEM and TEM. Silver-bearing polymeric micelles (PM-Ag) were characterized by DLS and LDE technics. EDX and UV-VIS spectroscopy confirmed silver nanoparticles' binding to PMs. Thermosensitive GLG hydrogel was considered a carrier for PM-Ag.Results: Encapsulation efficiency and drug loading content of micelles were calculated 64.53% and 14.6% respectively. The diameter and zeta potential of PMs were measured 166 ± 1.73 nm±SD and −6.26 ± 0.3 mV±SD and after silver-bearing it reached 197 ± 2.29 nm±SD and −5.38 ± 0.45 mV±SD respectively.Discussion: The biocompatibility of samples was investigated by MTT assay and the results indicated that up to a concentration of 125 µg/mL, the relative cell viability percentage exceeded 80%. Therefore, by considering the acceptable antifungal activity of the samples against C. Albicans, the designed drug delivery system is capable of sustained drug release over a specified period

    Development and optimization of the new ultrasonic-infrared-vacuum dryer in drying Kelussia odoratissima and its comparison with conventional methods

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    Among the post-harvest processing of medicinal plants, drying is an important and influential process. Given the numerous applications of medicinal plants, especially Kelussia odoratissima, in the food and pharmaceutical industries, the aim of this study was to compare the effects of the ultrasound-infrared radiation-vacuum method with conventional drying methods on the drying time, the total phenolic content (TPC), total flavonoid content (TFC) and antioxidant activity of K. odoratissima. ANOVA result showed that the effects of drying methods, drying temperature and their interaction effect on phenolic, flavonoid and antioxidant content were significant at 1% probability level. In the ultrasound-IR-vacuum method, by increasing temperature from 40 °C to 80 °C, the TFC increased by 35%. The highest antioxidant capacity was obtained for dry shade treatment, followed by dry sun treatment and three temperatures, i.e., 40 °C, 60 °C and 80 °C, in the combined method. The proposed optimal temperatures for the hot air, IR, and ultrasonic drying, were 63 °C, 66 °C and 71 °C, respectivel
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