82 research outputs found

    Effects of various penetration enhancers on percutaneous absorption of piroxicam from emulgels

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    A suitable emulgel formulation of piroxicam was prepared and its percutaneous permeation was investigated using Wistar rat skin and diffusion cell technique. The concentrations of the drug in receptor phase of diffusion cells were measured using HPLC method. The effect of three types of penetration enhancers (Myrj 52, cineol and Transcutol P) with different concentrations on transdermal permeation of the drug was also evaluated. Flux, Kp and enhancement ratios (ERs) of piroxicam in the presence of enhancers was measured and compared with emulgel base alone and simple commercial gel. The results showed a significant enhancement in the flux from emulgel base compared to hydroalcoholic gel formulation (9.91 folds over simple gel). The highest enhancement ratio (ER=3.11) was observed for Myrj 52 at the concentration of 0.25%. Higher concentrations of Myrj 52did not show any enhancement in the drug flux due to micelle formation and solubilization of the drug by micelles. The increase in solubility, in turn, increases the saturated concentration and reduces the thermodynamic activity of the drug. Transcutol® P with concentrations higher than 0.25% w/w showed burst transportation of the drug through the skin. All concentrations of cineol and Transcutol did not show any enhancing effects over emulgel base alone (ER <1)

    Transfer learning in hand movement intention detection based on surface electromyography signals

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    Over the past several years, electromyography (EMG) signals have been used as a natural interface to interact with computers and machines. Recently, deep learning algorithms such as Convolutional Neural Networks (CNNs) have gained interest for decoding the hand movement intention from EMG signals. However, deep networks require a large dataset to train appropriately. Creating such a database for a single subject could be very time-consuming. In this study, we addressed this issue from two perspectives: (i) we proposed a subject-transfer framework to use the knowledge learned from other subjects to compensate for a target subject’s limited data; (ii) we proposed a task-transfer framework in which the knowledge learned from a set of basic hand movements is used to classify more complex movements, which include a combination of mentioned basic movements. We introduced two CNN-based architectures for hand movement intention detection and a subject-transfer learning approach. Classifiers are tested on the Nearlab dataset, a sEMG hand/wrist movement dataset including 8 movements and 11 subjects, along with their combination, and on open-source hand sEMG dataset “NinaPro DataBase 2 (DB2).” For the Nearlab database, the subject-transfer learning approach improved the average classification accuracy of the proposed deep classifier from 92.60 to 93.30% when classifier was utilizing 10 other subjects’ data via our proposed framework. For Ninapro DB2 exercise B (17 hand movement classes), this improvement was from 81.43 to 82.87%. Moreover, three stages of analysis in task-transfer approach proved that it is possible to classify combination hand movements using the knowledge learned from a set of basic hand movements with zero, few samples and few seconds of data from the target movement classes. First stage takes advantage of shared muscle synergies to classify combined movements, while second and third stages take advantage of novel algorithms using few-shot learning and fine-tuning to use samples from target domain to further train the classifier trained on the source database. The use of information learned from basic hand movements improved classification accuracy of combined hand movements by 10%

    Sleep Patterns and Sleep Disorders in Primary School Children in Qazvin, Iran

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    ObjectiveSleep disorders are common in children; they also have a significant impact on the whole family, the parents in particular. Few studies in this field have been performed in Iran; hence the  present study was carried out in order to determine sleep patterns and the  prevalence of sleep disorders in school aged children in Qazvin.Material and MethodsThis cross sectional study was done on 300 students (150 males and 150 females) of elementary schools in Qazvin, selected from cluster random samples. The duration of the study was from November 2006 to February 2007, and data was acquired by means of a standard pediatric sleep questionnaire.ResultsThe prevalence of sleep disorder among subjects was 44.3% (47.3% in males, and 41.3% in females), and the disorder was severe in 21% of the studied children. Sleep patterns during the school days differed significantly from what was observed on Fridays (p=0.000). In addition, there was a significant difference between males and females in terms of duration of sleep on Fridays (p=0.014).ConclusionConsidering the high prevalence of sleep disorders in children, their harmful impact on the development of the  nervous system and the child's learning and psychological health as well as on parental competency, and again bearing in mind the low level of awareness among the general population about sleep hygiene, we strongly recommend educational programs via public media and via meetings with the parents in schools

    Closed Form Formulas for Distributed Circuit Model of Discontinuities in HTS Microstrip Transmission Lines

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    AbstractA distributed circuit model for different kinds of discontinuities in high temperature superconducting (HTS) microstrip transmission lines (TLs), is proposed. In each case, closed form formula for lumped element model is presented based on the configuration of the discontinuity and the characterizations of HTS microstrip TLs. These discontinuities consist of steps in width, open ends, gaps and 90-degree bends. In the case of normal conductor microstrip TLs there are a lot of numerical and analytical equations that can accurately model them, however those formulas are not efficient for HTS TLs. Thus modified relations are extracted utilizing the superconducting characterizations to obtain much more accurate formulas. Additionally temperature dependence of HTS TLs is considered in the relations. Moreover regarding the kinetic inductance in HTS TLs a closed form formula is proposed for characteristic impedance of HTS TLs. Furthermore correction factors based on fringe fields is used to optimize all formulas. Using these formulations can lead to modeling and analysis of some superconducting microwave devices such as resonators, microwave filters, couplers, etc. In contrast to EM analysis, using the distributed circuit model is much easier for analysis of HTS microwave devices. The accuracy of the proposed model is confirmed in comparison with some electromagnetic full-wave simulations. This full analytical approach shows great accuracy in this test case as well

    The Liquisolid technique: an overview

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    A novel "Powder Solution Technology" involves absorption and adsorption efficiency which makes use of liquid medications, drug suspensions admixed with suitable carriers, coating materials and formulated into free flowing, dry looking, non adherent and compressible powder forms. Based upon a new mathematical model expression, improved flow characteristics and hardness of the formulation has been achieved by changing the proportion of Avicel ® PH 200 and Aerosil ® PH 200 from 50:1 ratio to 5:1 and in which the drug is dispersed in an almost molecularly state. Due to their significantly improved wetting properties a greater drug surface area is exposed to the dissolution media, resulting in an increased dissolution rate and bio availability. By using the Liquisolid technique, sustained drug delivery systems were developed for the water soluble drugs in which hydrophobic non-volatile solvents are used as vehicles.A nova "Tecnologia da Solução Sólida" envolve eficiência de absorção e de adsorção, faz uso de medicações líquidas, suspensões de fármacos e misturas com transportadores adequados, materiais de cobertura e é formulada em formas sólidas em fluxo livre, secas, não aderentes e compressíveis. Com base em novo modelo matemático, características aprimoradas de fluxo e dureza da formulação foram alcançadas modificando-se a proporção de Avicel ® PH 200 e Aerosil ® PH 200 de 50:1 para 5:1, na qual o fármaco é disperso quase que no estado molecular. Devido às propriedades de umidificação significativamente aprimoradas e à área do fármaco exposta ao meio de dissolução, que resulta na velocidade de dissolução, a biodisponibilidade foi aumentada. Utilizando a técnica Liquisólido, desenvolveram-se sistemas de liberação controlada de fármacos solúveis em água, nos quais solventes hidrofóbicos não voláteis foram usados como veículos

    Frosted branch angiitis caused by Varicella Zoster virus in an immunocompetent patient

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    Introduction: Frosted branch angiitis(FBA) is a panuveitis with sheating of all retinal vesssels. Case presentation: Herein we report an immunocompetent person who presented with fever, headache, atypical rash, and hazy vision. Ophthalmoscopy of both eyes revealed perivascular sheathing with frosted branch angiitis pattern in veins, patchy retinal hemorrhages. Aqueous PCR analysis turned positive for VZV. Discussion: This case illustrates that VZV should be considered in the differential diagnosis of retinal perivasculitis. Since a rapid and accurate diagnosis is crucial for prompt administration of antiviral therapy, PCR-based analysis of aqueous humor is a valuable tool for detecting viruses. © 2015, IRAN. J. MICROBIOL. All rights reserved

    The relationship of parental pain catastrophizing with parents reports of children�s anxiety, depression, and headache severity

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    Objective Parental pain catastrophizing is a construct recognized to have a significant impact on experience of pain in both children and parents. This research aimed to investigate the probable relationship of parental pain catastrophizing with the parent�s reports of children�s anxiety, depression and headache severity amongst Iranian parents of children with chronic or recurrent headache. Materials & Methods This study was conducted in 2015-16, in two pediatric neurological centers located in Tehran, Iran; with a convenience sampling method and 212 parents (120 mothers and 92 fathers) of 132 children with a chronic or recurrent headache (migraine and tension-type). They completed the Pain Catastrophizing Scale; Numeric Pain Rating Scale, asking for the average of pain severity in last three months before the research, and the Anxiety and Depression subscales of the Children Behavioral Check List. Results The mean age of parents was 35.41 yr (SD=5.58) and the mean age of children was 9.83 yr (SD=2.77). A total of 72 girls and 60 boys participated in this study with a mean pain severity for headache in last three months before the research of 4.99 (SD=2.63). Probable sex differences according to parental pain catastrophizing, pain severity, anxiety, and depression were assessed amongst parents. In the next step, the predictability of pain severity from parental pain catastrophizing was evaluated. Results indicated a significant relationship in maternal pain catastrophizing and estimates of pain intensity by mothers. Conclusion These findings represent the importance of parent�s especially mother�s cognitive factors affecting their reports of their children�s pain and related emotional disturbances. © 2018, Iranian Child Neurology Society. All rights reserved

    Prediction of response to treatment in children with epilepsy

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    Abstract Objective: This study was conducted to predict the response to treatment in patients treated with anti-epilepsy drugs. Material and Methods: This analytical questionnaire-based study was conducted in 2014 among 128 patients with epilepsy admitted to Mofid Children's Hospital, Tehran, Iran. The inclusion criteria were children 2 months to 12 yr of age with epilepsy and patients who experienced fever and seizure attacks at least once were excluded from the study. Patients were followed up for 6 months and the response to their treatment was recorded. The good response to treatment was defined as the absence of seizure with two drugs during follow up. Results: Seventy-two patients (56.3%) were boys. The age of the first seizure was under 2 yr old in 90 patients (70.3%). History of febrile convulsion, family history of epilepsy and history of asphyxia was found in 16 (12.5%), 41 (32%), and 27 (21.1%) patients, respectively. Seizure etiology was idiopathic in 90 patients (70.3%), and the number of seizures was 1-2 in 36 patients (28.1%). Overall, 57 patients (44.5%) had cerebral lesion according to CT scan or MRI, and EEG was abnormal in 101 patients (78.9%). In 6-month follow-up, 40 patients (31.3%) responded well to the treatment and 88 patients (68.8%) responded poorly to the treatment. History of asphyxia (OR = 6.82), neonatal jaundice (OR = 2.81) and abnormal EEG (OR = 0.19) were effective factors in response to treatment. Conclusion: Abnormal EEG is an effective factor in treatment response in the children studied. Key Words: Pediatric, Anti-seizure drug, Response to treatment, Children, Epileps
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