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The attention network test (ANT) is a tool for assessing the executive, alerting, and orienting components of attention. However, conflicting findings exist regarding the nature and correlation between attention networks. This study aims to investigate the influence of eye movement time on the assessment of attention network efficiency. Forty male students, with an average age of 20.8 ± 1.3 years, participated in the study. The revised attention network test was conducted concurrently with the recording of the electrooculogram signal. The electrooculogram signal was used to estimate eye placement time on target stimuli. Considering eye movement time for calculating the score of each network was proposed as a novel method. The study explored the nature of attention networks and their relationships, and revealed significant effects for attention networks with and without considering the eye movement time. Additionally, a significant correlation is observed between the alerting and orienting networks. However, no significant correlation is found between attention networks using the proposed method. Considering eye movement time alters the assessment of attention network efficiency and modifies the correlation among attention networks.
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Atención , Electrooculografía , Movimientos Oculares , Humanos , Masculino , Atención/fisiología , Movimientos Oculares/fisiología , Adulto Joven , Función Ejecutiva/fisiología , Adulto , Tiempo de Reacción/fisiología , Orientación/fisiologíaRESUMEN
The attention networks test (ANT) is frequently utilized to evaluate executive, alerting, and orienting attentional components. Additionally, it serves as an activation task in neuroimaging studies. This study aimed to examine the relationship between attention networks and brain electrophysiology. The study enrolled 40 right-handed male students (age = 20.8 ± 1.3 years) who underwent the revised attention network test, while their electroencephalogram signals were recorded. The study aimed to explore the effects of attention networks and their efficiencies on brain electrophysiology. The results indicated that the P3 amplitude was modulated by the conflict effect in the central (p-value = 0.014) and parietal (p-value = 0.002) regions. The orienting component significantly influenced P1 and N1 latencies in the parietal and parieto-occipital regions (p-values < 0.006), as well as P1 and N1 amplitude in the parieto-occipital region (p-values = 0.017 and 0.011). The alerting component significantly affected P1 latency and amplitude in the parietal and parieto-occipital regions, respectively (p-value = 0.02). Furthermore, N1 amplitude and the time interval between P1 and N1 were significantly correlated with the efficiency of alerting and orienting networks. In terms of connectivity, the coherence of theta and alpha bands significantly decreased in the incongruent condition compared to the congruent condition. Additionally, the effects of attention networks on event-related spectral perturbation were observed. The study revealed the influence of attention networks on various aspects of brain electrophysiology. Specifically, the alerting score correlated with the amplitude of the N1 component in the double-cue and no-cue conditions in the parieto-occipital region, while the orienting score in the same region correlated with the N1 amplitude in the valid cue condition and the difference in N1 amplitude between the valid cue and double-cue conditions. Overall, empirical evidence suggests that attention networks not only impact the amplitudes of electrophysiological activities but also influence their time course.
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Encéfalo , Orientación , Humanos , Masculino , Adulto Joven , Adulto , Orientación/fisiología , Encéfalo/diagnóstico por imagen , Encéfalo/fisiología , Electroencefalografía , Lóbulo Occipital , Electrofisiología , Tiempo de Reacción/fisiologíaRESUMEN
Introduction: Lack of high-quality sleep causes severe side effects like anxiety and changes in plasma concentration of oxalate. The current study investigated the impact of local extremely low-frequency magnetic fields (ELF-MFs) on inducing sleep (sleepiness) and anxiety in male rats. Methods: In this experimental study, 40 male rats were divided into four groups (n=10 for each group). The ELF-MF exposure (0, 10, and 18 Hz) was applied with an intensity of 200µT for three days (10 min/d). The sham-treated animal did not receive ELF-MF. Serum levels of oxalic acid (OA) and sleepiness were measured before and after the last exposure to ELF-MF or sham. Anxiety, sleepiness, and OA were measured using the elevated plus maze, open-field test (OFT), and ELISA test. Results: A comparison of oxalate levels before and after exposure to ELF-MF revealed that ELF-MF (10 Hz) decreased the serum level of oxalate (P<0.05). Comparing open/closed arm entry (in an elevated plus maze) between before and after exposure to ELFMF revealed significant differences. Also, frequency, velocity, and distance moved were decreased in the open-field test. Conclusion: Results of the present study demonstrated that ELF-MF with short-time exposure may modulate the metabolism of OA and may modulate anxiety-like behavior or kind of induction of sleepiness in male rats. Highlights: Oxalate acid concentration may reduce after short time ELF-MF exposure.Locomotor activity in male rats may decrease after the ELF-MF exposure.Short time ELF-MF exposure may induce sleepiness in male rats that may be used to treat sleep disorders. Plain Language Summary: It is necessary for a person to have good sleep to feel happy during the day. The usual way to treat the patient's sleep disorders is drug therapy, but there are some non-pharmacological treatments such as cognitive behavioral therapy and proper diet. In this study we decided to evaluate the effect of ELF-MFs on sleep induction (sleepiness) in male rats by assessing behavioral tests and measuring oxalate acid density. The results showed that the activity of rats and oxalate acid concentration reduced after ELF-MF exposure. This was consistent with results of the plus maze test and the reduction of velocity, frequency and in the open-field test can be attributed to sleepiness. The results of this research showed that ELF-MF with short time exposure may modulate the anxiety-like behavior or kind of induction of sleepiness in male rats. This effect may be used to treat sleep disorders and requires further human studies.
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Introduction: This study assessed the effect of polarized low-level laser therapy (PLLLT) on the treatment of myofascial trigger points (MTrPs) in the trapezius muscles. Its effectiveness in pain reduction was compared to low-level laser therapy (LLLT). Methods: Sixty-four patients with MTrPs were randomly divided into 2 groups, namely PLLLT and LLLT. Each patient received treatment for a period of 2 weeks, 5 sessions a week. The intensity of laser irradiation to the skin surface was 6 J/cm2 . The system exit power was 160 mw at a 755 nm wavelength. The visual analog scale (VAS) for the 1st, 5th and 10th sessions was analyzed through two-way repeated measures ANOVA. Results: Increasing the number of treatment sessions was effective in reducing pain intensity (P>0.05). The effect of LLLT on pain reduction was significantly greater than that of PLLLT (P>0.05). Referred pain (RP), the limitation of neck movement (LNM), the presence of muscular taut band (PMTB) and the sensitivity of muscular taut band (SMTB) were reduced significantly by the end of the 10th session, compared with participants' condition at the beginning of the 1st session in both groups. Conclusion: PLLLT and LLLT can effectively treat MTrPs in the trapezius muscles and they reduce RP, LNM, PMTB, and SMTB in particular. However, the effect of the LLLT was significantly greater than that of PLLLT. In accordance with the observed results, LLLT is recommended as an effective method for treating MTrPs.
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Breast cancer is the most common cancer and the leading cause of cancer deaths in women worldwide. This study aimed to provide an automatic windowing method in mammograms, based on the principles of Otsu's thresholding function, to help radiologists more easily detect abnormalities on mammograms. A total of 322 mammographic images from the Mammographic Image Analysis Society (MIAS) database were used in the present study. The image background was removed based on Otsu's method. After selecting the threshold in the computer-aided windowing (CAW) system, the pixel values were kept larger than the threshold and displayed on a grayscale. A radiologist evaluated images randomly before and after CAW. Using CAW, the radiologist correctly diagnosed all healthy images (207 images). A total of 115 mammograms were evaluated to differentiate malignancy from benign masses. All 63 benign images were accurately diagnosed after using CAW. Moreover, of 52 malignant images, all were accurately recognized as malignant except one, which was recognized as benign. Therefore, specificity and sensitivity were significantly improved to 98% and 99.6%, respectively, and the area under the receiver operating characteristic (ROC) curve was calculated to be 0.99. The study showed that the use of CAW can potentially lead to quicker image assessment and improve the diagnostic accuracy of radiologists in differentiating between benign and malignant masses on mammograms.
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Mamografía , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Neoplasias de la Mama/diagnóstico por imagen , Humanos , Curva ROC , Factores de TiempoRESUMEN
BACKGROUND: Multiple sclerosis (MS) is a neurological disease for which to date there is no cure and the existing disease-modifying drugs just slow down the disease progression. PURPOSE: In this clinical trial we evaluated the efficacy of Achillea millefolium (A. millefolium) aqueous extract in MS patients. METHODS: A triple-blind randomized placebo-controlled parallel group trial was conducted on 75 MS patients. The patients were randomized into three groups including placebo and two groups receiving A. millefolium with two different doses, i.e. 250⯠mg/day and 500⯠mg/day, for 1 year. The primary outcome was the annualized relapse rate. Also, number and volume of lesions were obtained from magnetic resonance imaging (MRI) scans. Furthermore, we performed a comprehensive neurological and cognitive tests as follows: changes in the expanded disability status scale (EDSS), the multiple sclerosis functional composite (MSFC), fatigue severity scale (FSS), Ashworth spasticity assessment, Beck depression test, State-trait anxiety inventory (STAI), mini-mental status examination (MMSE), Wisconsin card sorting test (WCST), tower of London test (TOL), word-pair learning, paced auditory serial addition task (PASAT) and standard laboratory tests. RESULTS: This study showed one year administration of A. millefolium (both doses) decreased the annual relapse rate in MS patients. The mean volume change of lesions significantly decreased in the 500â¯mg A. millefolium group. The add-on therapy also increased time to first relapse and the MSFC z-score; it decreased the EDSS score and improved performance in word-pair learning, PASAT, and WCST. CONCLUSION: We found beneficial effects of A. millefolium aqueous extract as an add-on therapy in MS patients.
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Achillea/química , Esclerosis Múltiple/tratamiento farmacológico , Fitoterapia , Extractos Vegetales/uso terapéutico , Adulto , Progresión de la Enfermedad , Femenino , Humanos , Masculino , RecurrenciaRESUMEN
Purpose: Drug delivery has a critical role in the treatment of cancer, in particular, carbon nanotubes for their potential use in various biomedical devices and therapies. From many other materials which could be more biocompatible and biodegradable and which could form single-walled nanotubes, silicon carbide was selected. Methods: To compare two drug delivery systems based on single-walled nanotubes, molecular dynamic simulations were applied and encapsulation behavior of the drug carboplatin was investigated inside the silicon carbide nanotube and the carbon nanotube. Results: Localization of the carboplatin inside the nanotubes indicated that the carboplatin moves throughout the tubes and possesses a greater probability of finding the drug molecule along the nanotubes in the first quarter of the tubes. The energy analysis exhibited the lowest free energy of binding belongs to the encapsulation of the drug carboplatin in the silicon carbide nanotube, about -145 Kcal/mol. Conclusion: The results confirmed that the silicon carbide nanotube is a more suitable model than the carbon nanotube for drug delivery system based on nanotubes as a carrier of platinum-based anticancer drugs.
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Objectives Lack of high-quality sleep causes serious side effects. The current study aimed to investigate the impact of local extremely low frequency magnetic field (ELF-MF) on sleep and drowsiness in healthy young adults. Methods Sixty-five young adults (32 males and 31 females, aged 18-24, participated voluntarily in this randomized crossover clinical trial. 200 microTesla MF (3 minutes duration) at three frequencies (10, 14 and 18 Hz) was applied to the skull in areas C3, Cz and C4, respectively. The Stanford Sleepiness Scale (SSS) or Consciousness Test (CT), Epworth Sleepiness Scale (ESS) and Peabody Picture Vocabulary Test were used to evaluate drowsiness, sleepiness, and reaction time. These tests were done both before and after application of ELF-MF or sham operation. Results Minimum reaction time after exposure to ELF-MF increased compared to that before exposure (P = 0.03), while it was not significant for the sham group (P = 0.63). From the ESS questionnaire, the results indicated that there was no significant difference for males or females between the exposure and sham groups. The mean of the SSS scores was no different compared to that before exposure. Conclusion The results of this study demonstrated that exposure to ELF-MF may influence reaction time in young healthy people. However, as the results of ESS and SSS were not different between exposure and non-exposure groups, further studies using larger sample sizes are recommended in order to reach better interpretations of the effects of ELF-MF on sleepiness in young people.
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Magnetoterapia , Tiempo de Reacción , Vigilia , Adolescente , Estudios Cruzados , Femenino , Humanos , Campos Magnéticos , Masculino , Factores Sexuales , Sueño , Estudiantes , Encuestas y Cuestionarios , Resultado del Tratamiento , Adulto JovenRESUMEN
The recorded EEG of some brain regions of patients such as attention deficit hyperactivity disorder (ADHD), depression and etc. are different in comparison to healthy people. The disease improves with modifying the patient EEG that this is the basis of neurofeedback training. The main disadvantage of neurofeedback training demands patient's collaborative and active participation during treatment sessions, while some of patients such as addicts, depressed people and ADHD children cannot easily concentrate in direction of therapist's purpose. Furthermore, extremely low frequency magnetic fields (MFs) can affect brain signals and change them that in some cases lead to clinical effects. This report proposes if by locating small coils in desired region proceeds to local exposure of brain and happens in different frequencies or intensities and the effects of each MF in brain signals get analyzed then by knowing its effects we can make changes in patient voluntary without direct participation of patient in his/her brain signal changes. In the other words by changing type of the MF exposure and immediate record of brain signals we can fallow brain signals by observing the immediate record after exposure, with changes in the amplitude and the next exposure frequency, the therapist tries to direct the brain signal of desired region to the purpose. The possibility of approving this hypothesis in spite of contradictory effects about recovery or appearance of depression because of the MF and ability of local magnetic field exposures in changing of brain signals get reinforced to some extent.
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Magnetoterapia/métodos , Trastornos Mentales/terapia , Neurorretroalimentación/métodos , Encéfalo , Electroencefalografía , Campos Electromagnéticos , Humanos , Magnetoterapia/tendenciasRESUMEN
Determination of the equivalent square fields for rectangular and shielded fields is of great importance in radiotherapy centers and treatment planning software. This is accomplished using standard tables and empirical formulas. The goal of this paper is to present a formula based on analysis of scatter reduction due to inverse square law to obtain equivalent field. Tables are published by different agencies such as ICRU (International Commission on Radiation Units and measurements), which are based on experimental data; but there exist mathematical formulas that yield the equivalent square field of an irregular rectangular field which are used extensively in computation techniques for dose determination. These processes lead to some complicated and time-consuming formulas for which the current study was designed. In this work, considering the portion of scattered radiation in absorbed dose at a point of measurement, a numerical formula was obtained based on which a simple formula was developed to calculate equivalent square field. Using polar coordinate and inverse square law will lead to a simple formula for calculation of equivalent field. The presented method is an analytical approach based on which one can estimate the equivalent square field of a rectangular field and may be used for a shielded field or an off-axis point. Besides, one can calculate equivalent field of rectangular field with the concept of decreased scatter radiation with inverse square law with a good approximation. This method may be useful in computing Percentage Depth Dose and Tissue-Phantom Ratio which are extensively used in treatment planning.