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1.
Brain Sci ; 14(2)2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-38391702

RESUMEN

Children with developmental dyslexia (DD) often struggle with executive function difficulties which can continue into adulthood if not addressed. This double-blinded randomized clinical trial study evaluated the short-term effects of the Verbal Working Memory-Balance (VWM-B) program on reading-related executive functions, reading skills, and reading comprehension in Persian children with DD. The active control group [12 children with DD with a mean age of 9 years (SD = 0.90)] received training using the single-task VWM program, while the experiment group [15 children with DD with a mean age of 8 years (SD = 0.74)] received training with the dual-task VWM-B program. Both groups received fifteen training sessions, and assessments were conducted before and after the intervention. The groups were homogenized for possible confounders of age, gender, IQ level, and attention level. The study employed separate mixed ANOVA analyses to estimate the impact of training programs on various measured functions. Significant improvements were observed in the outcome measures of backward digit span, text comprehension, verbal fluency, Stroop color-word test and interference, and the reading subtests. Additionally, significant correlations were found between reading skills and backward digit span, text comprehension, verbal fluency, and Stroop variables. In conclusion, the dual-task VWM-B program was found to be more effective than the single-task VWM program in improving selective attention, cognitive inhibition, verbal working memory capacity, information processing speed, naming ability, and lexical access speed. These enhanced executive functions were associated with improved reading skills in children with DD.

2.
Dyslexia ; 29(3): 264-285, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37337459

RESUMEN

Sufficient activation of the left fusiform gyrus is important in reading ability acquisition due to its role in reading and naming, working memory (WM), and balance tasks. Recently, a newly-designed training program, Verbal Working Memory-Balance (VWM-B), has been evaluated on children with dyslexia, and its positive effects were shown on reading ability, WM capacity, and postural control. In the present study, we aimed to estimate the functional connectivity alterations of the left fusiform gyrus following training by the VWM-B. Before and after 15 sessions of training, the fMRI and other tools data were collected on a sample of children with dyslexia, who were allocated into two control and experiment groups. Data analyses showed the increased functional connectivity of the left fusiform gyrus between the left anterior temporal fusiform cortex, left and right Crus II regions of the cerebellum, and the left middle frontal gyrus. Moreover, VWM-B training significantly improved the reading and naming ability, WM capacity, and postural control of participants in the experiment group in comparison to the control. The current study findings emphasize the critical role of the left fusiform gyrus in reading ability. Moreover, it provides evidence to support the existence of cerebellar deficits in dyslexia.


Asunto(s)
Dislexia , Humanos , Niño , Dislexia/diagnóstico por imagen , Memoria a Corto Plazo , Lectura , Lóbulo Temporal/diagnóstico por imagen , Imagen por Resonancia Magnética
3.
BMC Musculoskelet Disord ; 23(1): 33, 2022 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-34986825

RESUMEN

BACKGROUND: Biomechanical risk factors have been identified as the main predisposing factor of chronic low back pain (CLBP), especially in Army personnel. The Job Requirements and Physical Demands (JRPD) questionnaire has been developed to assess the biomechanical exposures related to CLBP. Examining the biomechanical risk factors could prevent CLBP. This study aimed to translate and cross-culturally adapt the JRPD into Persian and assess its psychometric properties among Iranian male Army personnel with CLBP. METHODS: In this cross-sectional study, the content validation of the JRPD was assessed after translating to Persian. The Persian JRPD was administered to 198 male Army personnel with CLBP, with an interval of 7 days, to assess test-retest reliability, including Cronbach's α, intraclass correlation coefficients (ICC), standard error of measurement (SEM), and minimal detectable change at 95% confidence interval (MDC95%). Scores of the Persian JRPD were correlated with the scores of visual analog scale (VAS), Borg's category-ratio (CR10) scale, general health questionnaire-28 (GHQ-28), and physical functioning (PF1 and PF2) subscale of the 12-item short-form health survey (SF-12) to assess convergent validity using Spearman correlation for a priori hypotheses. RESULTS: The Persian JRPD had good content validity evidenced by the higher content validity index (> 0.70). The questionnaire had a significant positive negligible to weak correlation with the VAS (rho = 0.27; p < 0.001), Borg's CR10 scale (rho = 0.19; p = 0.009), and the total score of GHQ-28 and its domains (rho ≤0.34; p < 0.05); and significant negative weak correlation with PF2 (rho = - 0.27; p < 0.001) and significant negative moderate correlation with PF1 (rho = - 0.35; p < 0.001), thus confirming the priori hypotheses (89%, 8/9). The internal consistency and ICC (α = 0.91; ICC = 0.80) were highly adequate, with SEM and MDC95% of 7.91 and 21.3 respectively. CONCLUSIONS: The JRPD was successfully adapted into Persian and had adequate psychometric properties in terms of content and convergent validity, internal consistency, and test-retest reliability. The questionnaire is found useable to assess the CLBP-related biomechanical exposures in Iranian male Army personnel.


Asunto(s)
Dolor de la Región Lumbar , Personal Militar , Comparación Transcultural , Estudios Transversales , Humanos , Irán/epidemiología , Dolor de la Región Lumbar/diagnóstico , Dolor de la Región Lumbar/epidemiología , Masculino , Psicometría , Reproducibilidad de los Resultados , Encuestas y Cuestionarios
4.
BMC Neurosci ; 22(1): 55, 2021 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-34525977

RESUMEN

BACKGROUND: It is important to improve verbal Working Memory (WM) in reading disability, as it is a key factor in learning. There are commercial verbal WM training programs, which have some short-term effects only on the verbal WM capacity, not reading. However, because of some weaknesses in current verbal WM training programs, researchers suggested designing and developing newly structured programs that particularly target educational functions such as reading skills. In the current double-blind randomized clinical trial study, we designed a new Verbal Working Memory-Balance (VWM-B) program which was carried out using a portable robotic device. The short-term effects of the VWM-B program, on verbal WM capacity, reading skills, and postural control were investigated in Iranian children with developmental dyslexia. RESULTS: The effectiveness of the VWM-B program was compared with the VWM-program as a traditional verbal WM training. In comparison with VWM-program, the participants who received training by the VWM-B program showed superior performance on verbal WM capacity, reading skills, and postural control after a short-term intervention. CONCLUSIONS: We proposed that the automatized postural control resulting from VWM-B training had a positive impact on improving verbal WM capacity and reading ability. Based on the critical role of the cerebellum in automatizing skills, our findings support the cerebellar deficit theory in dyslexia. TRIAL REGISTRATION: This trial was (retrospectively) registered on 8 February 2018 with the Iranian Registry of Clinical Trials (IRCT20171219037953N1).


Asunto(s)
Dislexia/fisiopatología , Dislexia/terapia , Memoria a Corto Plazo/fisiología , Equilibrio Postural/fisiología , Robótica/métodos , Aprendizaje Verbal/fisiología , Niño , Método Doble Ciego , Dislexia/epidemiología , Femenino , Humanos , Irán/epidemiología , Masculino
5.
Nano Lett ; 21(13): 5614-5619, 2021 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-34161104

RESUMEN

We demonstrate superconducting vertical interconnect access (VIA) contacts to a monolayer of molybdenum disulfide (MoS2), a layered semiconductor with highly relevant electronic and optical properties. As a contact material we use MoRe, a superconductor with a high critical magnetic field and high critical temperature. The electron transport is mostly dominated by a single superconductor/normal conductor junction with a clear superconductor gap. In addition, we find MoS2 regions that are strongly coupled to the superconductor, resulting in resonant Andreev tunneling and junction-dependent gap characteristics, suggesting a superconducting proximity effect. Magnetoresistance measurements show that the bandstructure and the high intrinsic carrier mobility remain intact in the bulk of the MoS2. This type of VIA contact is applicable to a large variety of layered materials and superconducting contacts, opening up a path to monolayer semiconductors as a platform for superconducting hybrid devices.

6.
Exp Clin Transplant ; 19(1): 20-24, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32490760

RESUMEN

OBJECTIVES: A lack of donors continues to be a significant problem. Kidney donors with a body mass index ≥ 30 kg/m² are not suitable for laparoscopic donor nephrectomy; however, some studies have suggested that an obese donor could be an appropriate donor with similar surgical outcomes. Here, we report the results of our 10-year experience of laparoscopic donor nephrectomy, examining the effects of body mass index on the surgical results of laparoscopic donor nephrectomy. MATERIALS AND METHODS: We retrospectively reviewed medical records of patients who underwent laparoscopic donor nephrectomy at the Shahid Beheshti University Medical Science, Urology Center (Tehran, Iran) from 2005 to 2015. The collected information included pretransplant and posttransplant serum levels of hemoglobin and creatinine. We also collected data on surgical outcomes (operation time, cold and warm ischemia, need for blood transfusion, and conversion to open surgery, length of hospital stay, and complication rates) with respect to body mass index categories (≤ 24.9, 25-29.9, and ≥ 30 kg/m²). RESULTS: Of 1083 kidney donors, 732 donors had body mass index of ≤ 24.9 kg/m², 256 had body mass index between 25 and 29.9 kg/m², and 95 had body mass index of ≥ 30 kg/m². Differences among groups were not significant in terms of operation time (P = .558), warm or cold ischemic time (P = .829 and .951, respectively), blood transfusion (P = .873), and length of hospital stay (P = .850). CONCLUSIONS: The laparoscopic approach for donor nephrectomy is a safe and effective method in obese donors without significant postoperative complications.


Asunto(s)
Trasplante de Riñón , Laparoscopía , Nefrectomía , Obesidad , Donantes de Tejidos , Humanos , Irán , Nefrectomía/métodos , Estudios Retrospectivos
7.
Biomed Eng Online ; 19(1): 64, 2020 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-32811522

RESUMEN

BACKGROUND: Fear of falling (FoF) is defined as a lasting concern about falling that causes a person to limit or even stop the daily activities that he/she is capable of. Seventy percent of Parkinson's disease (PD) patients report activity limitations due to FoF. Timely identification of FoF is critical to prevent its additional adverse effects on the quality of life. Self-report questionnaires are commonly used to evaluate the FoF, which may be prone to human error. OBJECTIVES: In this study, we attempted to identify a new postural stability-indicator to objectively predict the intensity of FoF and its related behavior(s) in PD patients. METHODS: Thirty-eight PD patients participated in the study (mean age, 61.2 years), among whom 10 (26.32%) were identified with low FoF and the rest (73.68%) with high FoF, based on Falls Efficacy Scale-International (FES-I). We used a limit of stability task calibrated to each individual and investigated the postural strategies to predict the intensity of FoF. New parameters (FTRis; functional time ratio) were extracted based on the center of pressure presence pattern in different rectangular areas (i = 1, 2, and 3). The task was performed on two heights to investigate FoF-related behavior(s). RESULTS: FTR1/2 (the ratio between FTR1 and FTR2) was strongly correlated with the FES-I (r = - 0.63, p < 0.001), Pull test (r = - 0.65, p < 0.001), Timed Up and Go test (r = - 0.57, p < 0.001), and Berg Balance Scale (r = 0.62, p < 0.001). The model of FTR1/2 was identified as a best-fitting model to predicting the intensity of FoF in PD participants (sensitivity = 96.43%, specificity = 80%), using a threshold level of ≤ 2.83. CONCLUSIONS: Using the proposed assessment technique, we can accurately predict the intensity of FoF in PD patients. Also, the FTR1/2 index can be potentially considered as a mechanical biomarker to sense the FoF-related postural instability in PD patients.


Asunto(s)
Accidentes por Caídas , Miedo , Enfermedad de Parkinson/fisiopatología , Enfermedad de Parkinson/psicología , Equilibrio Postural , Femenino , Humanos , Masculino , Persona de Mediana Edad
8.
Urologia ; 87(4): 178-184, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32493134

RESUMEN

BACKGROUND: There is a growing concern about postsurgical outcomes of radical prostatectomy, especially in the younger population and patients with earlier tumor stages. Here, we present our 17 years' experience of sutureless vesico-urethral alignment after radical prostatectomy with a focus on postoperative functional urinary outcomes. METHODS: Data of 784 patients who underwent radical prostatectomy during 2001-2017 were evaluated retrospectively. Before surgery, patients' demographic information, pathologic stage, margin of surgery, prostate-specific antigen, and Gleason score were obtained. Then, serum prostate-specific antigen level, urinary continence, potency, and other functional outcomes of surgery were recorded after each postoperative visit. RESULTS: The mean age (±standard deviation) of patients was 61.3 (±6.30) years. The median (IQ25-75) duration of follow-up was 30 (12-72) months. Full continence was achieved in 90% and 95.9% of patients at 3 and 6 months post surgery and 96.4% of the patients were continent at the last follow-up visit. Bladder neck stricture occurred in 167 patients (21.3%). During the follow-up period, none of the patients complained of total incontinence and at the last visit, 36.6% of patients reported potency. The frequency of grade 2 continence was significantly higher in patients with high-stage tumors (T3/T4), high Gleason score (⩾8), high preoperative serum prostate-specific antigen (>20 ng/dL), and positive margin of surgery. Potency had a significant relationship with age, stage of the disease, and preoperative prostate-specific antigen. CONCLUSION: Maximal sparing of intrapelvic urethral length through sutureless vesico-urethral alignment technique results in excellent early urinary continence recovery after radical prostatectomy. A more advanced tumor stage (T1/T2), a higher Gleason score, high preoperative prostate-specific antigen, as well as positive surgical margin are risk factors of postoperative incontinence in patients who undergo radical prostatectomy.


Asunto(s)
Tratamientos Conservadores del Órgano/métodos , Complicaciones Posoperatorias/prevención & control , Prostatectomía/métodos , Neoplasias de la Próstata/cirugía , Procedimientos Quirúrgicos sin Sutura , Uretra , Incontinencia Urinaria/prevención & control , Anciano , Humanos , Masculino , Persona de Mediana Edad , Recuperación de la Función , Estudios Retrospectivos , Factores de Tiempo , Micción
9.
Ann Nucl Med ; 34(8): 521-526, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32447628

RESUMEN

OBJECTIVE: When using perfusion only modified PIOPED II criteria for PE detection, generated non-diagnostic scans are found to be the main diagnostic restriction. The objective of current study is to identify the role of Wells criteria added to inconclusive readings with the intent of enhancing the lung scintigraphy diagnostic yield. METHODS: CTPA was performed in 34 suspected PE patients with inconclusive lung scintigraphy. They also were evaluated by Wells score and classified as low, intermediate and high probability. Overall prevalence and the rate of PE for each probability were calculated. Furthermore, NPV for scores < 2 and PPV for scores > 6 were computed. RESULTS: Having a mean age of 59.75 ± 17.38 years, 7 (20.6%), 23 (67.6%) and 4 (11.8%) of cases had total criteria point count < 2, 2-6 and > 6, respectively. Using CTPA, 5 patients (14.7%) were diagnosed with PE. None of the patients with scores < 2 had PE with an associated NVP of 100%. Patients with scores 2-6 had a PE rate of 4.3% and 100% of patients with scores > 6 were diagnosed with PE, implying that the PPV of scores > 6 was 100%. CONCLUSION: Adding Wells score to non-diagnostic scans allowed identification of PE to be done reliably, and provided further insight into how lung scintigraphy in conjunction with clinical assessment is a practical strategy not only for the patients unfit for performing CTPA but also in all the patients referred for PE evaluation.


Asunto(s)
Pulmón/diagnóstico por imagen , Imagen de Perfusión , Embolia Pulmonar/diagnóstico por imagen , Enfermedad Aguda , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tomografía Computarizada por Rayos X
10.
Rehabil Res Pract ; 2020: 8854435, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33457016

RESUMEN

BACKGROUND: Literature indicated some risk factors for low back pain; however, there is insufficient knowledge on the effect of caring-related physical activities and individual characteristics on Chronic Low Back Pain (CLBP) in mothers of children with Cerebral Palsy (CP). OBJECTIVE: The main aim of the current study was to determine the association between caring-related physical activities, Body Mass Index (BMI), education level, and CLBP in mothers of children with CP. DESIGN: Case-control observational study. Setting. Pediatric rehabilitation clinics. Participants. Mothers of children with CP. Main Outcome Measures. Measures is comprised of a self-administered questionnaire that included the demographic characteristics items, pain visual analog scale, and three items of the job-related physical demands questionnaire. The logistic regression model served to assess the association. RESULTS: The control group included 81 healthy mothers, with a mean (SD) age of 39 (8.45) years, and the case group contained 90 mothers who suffered from CLBP, with a mean (SD) age of 37 (8.64) years. Performing lifting movements (OR 13.73, ß = 2.62, p < .001), BMI (OR 11.85, ß = 2.47, p = .011), repetitive bending (OR 7.67, ß = 2.04, p = .010), forward-flexion (OR 6.71, ß = 1.91, p = .033), and level of education (OR .21, ß = -1.53, p = .020), in descending order of odds ratios, were found to be significant predictors of the CLBP in mothers of children with CP. CONCLUSION: Avoiding caring-related harmful physical activities, maintaining body weight within a healthy range, and increasing knowledge for accurate lifting/handling techniques can be helpful to prevent the CLBP in mothers of children with CP.

11.
Urologia ; 86(4): 211-215, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31268823

RESUMEN

INTRODUCTION: In this study, we aimed to evaluate the safety and efficacy of the percutaneous nephrolithotomy procedure performed with adult-sized instruments in pediatric cases with staghorn kidney stone. METHODS: We retrospectively evaluated the efficacy and safety of 94 percutaneous nephrolithotomy procedures performed during 15 years in a single center for 82 pediatric patients with staghorn calculi using adult-sized instruments (24-Fr nephroscope). Stone free status was defined as complete clearance of the stones or the presence of insignificant residual stones of <3 mm in diameter. RESULTS: The mean age was 108 ± 53 months (range, 14-180 months). There were 39 patients (48%) with complete staghorn stones and 43 cases (52%) with partial staghorn. We fulfilled 91.4% of operations through a single access. The stone free rate was 86.6% after one percutaneous nephrolithotomy session. In total, seven patients referred for shock wave lithotripsy and four cases were scheduled for the second percutaneous nephrolithotomy session. Fever occurred in 18 patients (21%) and bleeding requiring transfusion in four children (5%). Prolonged leakage from nephrostomy site requiring anesthesia for double J stent placement occurred in one patient. No grade IV or V Clavien complication occurred. CONCLUSION: The success rate and complications of percutaneous nephrolithotomy with adult-size instruments in pediatric patients are acceptable.


Asunto(s)
Nefrolitotomía Percutánea/instrumentación , Cálculos Coraliformes/cirugía , Adolescente , Factores de Edad , Niño , Preescolar , Diseño de Equipo , Femenino , Humanos , Lactante , Masculino , Estudios Retrospectivos
12.
Urol J ; 16(2): 193-197, 2019 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-30471077

RESUMEN

OBJECTIVE: To evaluate long term outcomes of autologous pubovaginal fascial sling (AFPVS) as a salvage procedure following different types of failed anti-incontinence surgeries. MATERIALS AND METHODS: We retrospectively reviewed medical records of patients who had undergone salvage AFPVS after any kind of anti-incontinence surgery from 2005-2015 at our medical center. Patients were contacted by telephone. Revised Urinary Incontinence Scale (RUIS) was used to determine the success rate. RESULTS: A total of 40 patients out of 51 were successfully contacted. Mean patient age was 50.8± 9.8 years (range30-75) and mean follow up was 62.6±32.4 months (range12-120). Of 40 patients, 14(35%) had pure SUI and 26(65%) complained of mixed urinary incontinence. A total of 15(37.5%) patients had a failed Burch colposuspention, 5(12.5%) TVT, 8(20%) TOT, 3 (7.5%) AFPVS and five (12.5%) patients had history of failed mini-sling procedure. Four (10%) patients had undergone more than one anti incontinence surgeries. Overall success rate was 65% in our study. New onset urge urinary incontinence was detected in 25% of patient which was negatively associated with satisfaction and recommendation.  There was no statistically significant correlation between mixed urinary incontinence, type or number of previous failed surgeries with success however presence of pure SUI had a strongCOCLUSION: Autologous pubovaginal fascial sling might be considered as a safe and efficacious salvage surgical option following failed midurethral slings, Burch colposuspention and even AFPVS itself. It will provide reasonable long term results with no major complications.


Asunto(s)
Fascia/trasplante , Incontinencia Urinaria/cirugía , Adulto , Anciano , Autoinjertos , Femenino , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Estudios Retrospectivos , Terapia Recuperativa , Procedimientos Quirúrgicos Urológicos/métodos
13.
Urologia ; 85(1): 3-9, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28983892

RESUMEN

BACKGROUND: This systematic review and meta-analysis was designed to evaluate the post-operative outcomes between tubeless and standard percutaneous nephrolithotomy (PCNL) among children. METHODS: Literature searches were performed following the Cochrane guidelines. We conducted a systematic review and meta-analysis that included three trials investigating the outcomes including the length of hospital stay, operation time, hemoglobin decrease, blood transfusion rate, perirenal fluid presence, post-operative fever, stone clearance rate, and the need for a second operation. RESULTS: The patients who underwent tubeless PCNL had shorter length of hospitalization compared to standard PCNLs (mean difference -1.57, 95% confidence interval -3.2 to 0.07, p = 0.06). No significant decrease was detected in hemoglobin after tubeless PCNL compared to standard PCNL (mean difference 0.05, 95% confidence interval -0.03 to 0.13, p = 0.21). There were no significant differences in operation time (p = 0.7), perirenal fluid presence (p = 0.15), post-operative fever (p = 0.72), stone clearance (p = 0.68), and the need for a second operation (p = 0.90). CONCLUSIONS: This study showed no significant difference between tubeless and standard PCNLs in children. However, due to the lack of data, the results should be mentioned prudently. Future randomized trials with more sample sizes and longer follow-ups are warranted.


Asunto(s)
Transfusión Sanguínea , Cálculos Renales/cirugía , Tiempo de Internación , Nefrolitotomía Percutánea , Niño , Ensayos Clínicos como Asunto , Humanos , Nefrolitotomía Percutánea/métodos , Tempo Operativo , Dolor Postoperatorio/etiología , Factores de Riesgo , Resultado del Tratamiento
14.
J Reprod Infertil ; 18(1): 162-171, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28377895

RESUMEN

BACKGROUND: The aim of the present study was to evaluate the effectiveness of human ovarian vitrification protocol followed with in vitro culture at the morphological and molecular levels. METHODS: Ovarian tissues were obtained from 10 normal transsexual women and cut into small pieces and were divided into non-vitrified and vitrified groups and some of the tissues fragments in both groups were randomly cultured for two weeks. The morphological study using hematoxylin and eosin and Masson's trichrome staining was done. The analysis of mean follicular density, 17-ß estradiol (E2) and anti mullerian hormone (AMH), and real-time RT-PCR was down for the evaluation of expression of genes related to folliculogenesis. Data were compared by paired-samples and independent-samples T test. Values of p<0.05 were considered statistically significant. RESULTS: The proportion of normal follicles did not show significant difference between vitrified and non-vitrified groups before and after culture but these rates and the mean follicle density significantly decreased in both cultured tissues (p<0.05). The expression of genes was similar in vitrified and non-vitrified groups but in cultured tissues the expression of GDF9 and FSHR genes increased and the expression of FIGLA and KIT-L genes decreased (p<0.05). An increase in E2 and AMH concentration was observed after 14 days of culture in both groups. CONCLUSION: In conclusion, the present study indicated that the follicular development and gene expression in vitrified ovarian tissue was not altered before and after in vitro culture, thus this method could be useful for fertility preservation; however, additional studies are needed to improve the culture condition.

15.
Nano Lett ; 17(3): 1762-1767, 2017 03 08.
Artículo en Inglés | MEDLINE | ID: mdl-28221803

RESUMEN

Controlling solid state phase transitions via external stimuli offers rich physics along with possibilities of unparalleled applications in electronics and optics. The well-known metal-insulator transition (MIT) in vanadium dioxide (VO2) is one instance of such phase transitions emerging from strong electronic correlations. Inducing the MIT using electric field has been investigated extensively for the applications in electrical and ultrafast optical switching. However, as the Thomas-Fermi screening length is very short, for considerable alteration in the material's properties with electric field induced MIT, crystals below 10 nm are needed. So far, the only way to achieve thin crystals of VO2 has been via epitaxial growth techniques. Yet, stress due to lattice mismatch as well as interdiffusion with the substrate complicate the studies. Here, we show that free-standing vapor-phase grown crystals of VO2 can be milled down to the desired thickness using argon ion-beam milling without compromising their electronic and structural properties. Among our results, we show that even below 4 nm thickness the MIT persists and the transition temperature is lowered in two-terminal devices as the crystal gets thinner. The findings in this Letter can be applied to similar strongly correlated materials to study quantum confinement effects.

16.
Urologia ; 84(1): 48-50, 2017 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-28058716

RESUMEN

BACKGROUND: Open trigonoplasty antireflux operation has been associated with promising results. However, its success in controlling reflux has not been evaluated in the long term. METHODS: All patients who underwent trigonoplasty for vesicoureteral reflux by one surgeon from 2004 to 2014 were included. Preoperative evaluations included direct radionuclide cystography (DRNC) or voiding cystourethrography, urine analysis and culture and abdominal sonography. Urodynamic study and cystoscopy was performed in selected patients. Trigonoplasty was done by a modified Gil-Verent method. The latest available patients' DRNCs were used to judge for reflux relapse. RESULTS: Ninety-one patients, 142 refluxing units; median (range) age, 10.5 (1-45) years; M/F, (11/80) were followed for 18 to 135 months. Reflux resolution rate was 73.6% for patients and 75.4% for refluxing units. Relapse was associated with reflux grade (67% in grade V), ureteral orifice appearance (40% in golf hole/stadium), and patients with a history of pyelonephritis. Multivariable model based on the above variables had less than 10% sensitivity in predicting relapse. CONCLUSIONS: Trigonoplasty success rate can decrease with long-term follow-up.


Asunto(s)
Reflujo Vesicoureteral/cirugía , Adolescente , Adulto , Niño , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Lactante , Masculino , Persona de Mediana Edad , Músculo Liso/cirugía , Factores de Tiempo , Vejiga Urinaria/cirugía , Procedimientos Quirúrgicos Urológicos/métodos , Adulto Joven
17.
Urologia ; 84(1): 28-34, 2017 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-27911457

RESUMEN

BACKGROUND: Extracorporeal shock wave lithotripsy (ESWL) is an important tool for the management of urolithiasis. The effects of shockwaves on tissues are established. The aim of this meta-analysis is to evaluate the microscopic semen characteristics of young men before and after ESWL treatment for lower ureteral calculi. METHODS: Literature searches were performed following the Cochrane guidelines. We conducted a systematic review and meta-analysis that included six trials that investigated the effects of ESWL on semen parameters, including sperm concentration, motility, and hematospermia. Meta-analyses were performed using fixed and random-effects models with tests for publication bias and heterogeneity. RESULTS: Significant worsening was detected in sperm concentration and motility after ESWL between case and control groups (mean difference -17.23, 95% confidence interval -22.53 to -11.93, p<0.00001, mean difference -10.82, 95% confidence interval -18.56 to -3.07, p = 0.006). Rate of microscopic and macroscopic hematospermia was significantly higher after ESWL between case and control groups [risk ratio (RR) 40.00, 95% confidence interval 10.11-158.30, p<0.00001, RR 14.33, 95% confidence interval 2.82-72.90, p = 0.001]. All parameters recovered after 3 months. CONCLUSIONS: This study showed sperm concentration, motility, and rate of hematospermia (microscopic and macroscopic) were affected by ESWL that was used for the treatment of lower ureteral stone. Long-term studies with a focus on male fertility (i.e., pregnancy rates) after ESWL are warranted.


Asunto(s)
Litotricia , Semen , Humanos , Masculino , Análisis de Semen
18.
Physiol Mol Biol Plants ; 22(1): 153-61, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27186029

RESUMEN

To determine the effective traits to improve saffron yield, a split plot design based on RBCD was done in Mashhad region in Iran for three years (2012-2014). The results showed that all traits except number of daughter corm, fresh weight of daughter corm and dry leaf weight had low general heritability. Results of genotypic and phenotypic coefficients of variation and genetic advance demonstrated that the majority of traits had a low diversity and the selection did not have any effect in improving the traits. As a result, the best way to increase saffron yield is improvement of farm management. It was also found that saffron yield had the highest phenotypic and genotypic correlations with fresh and dry weight of daughter corm and dry and fresh flower weight. Therefore, the efforts to improve these traits will increase saffron yield. According to the present study 5-Jun to 5-Jul was found to be the best sowing date for planting saffron. Also, the Mashhad and Torbat ecotypes were the best ecotypes in this study. Phenotypic and genotypic path analysis showed that in the first step three traits number of daughter corm, fresh flower weight and flower number and in the second step traits fresh weight of daughter corm, dry flower weight and dry leaf weight interred to the regression model and had the highest positive direct and indirect effects on saffron yield. Mainly, it can be derived that the implementation of correct farm management including appropriate sowing date, saffron ecotypes, proper density, bigger and higher quality saffron corm can play an important role in improving yield components and subsequently increasing saffron yield.

19.
Pharmacol Biochem Behav ; 100(3): 425-30, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22009032

RESUMEN

Lithium is a major drug for bipolar disorder and mania. Recently, many studies have shown the neuroprotective effect of lithium in different models of neurodegenerative diseases. The present study was carried out to examine the effect of lithium in a rat model of neuropathic pain induced by partial sciatic nerve ligation and the possible role of opioid system in this effect. To do so, animals received acute injection of saline, lithium (5, 10 and 15 mg/kg,) and naloxone (1 mg/kg) or the combination of naloxone (1 mg/kg) with lithium (10 mg/kg) intraperitoneally on the testing days. Thermal hyperalgesia, mechanical and cold allodynia were measured on the days 3, 5, 7, 10 and 14 after surgery. Lithium decreased thermal hyperalgesia scores with dose of 5, 10 and 15 mg/kg and cold and mechanical allodynia scores with dose of 10 and 15 mg/kg, significantly. The opioid antagonist naloxone prevented the effect of lithium on thermal hyperalgesia and mechanical allodynia while it did not show any effect on the acetone-induced cold allodynia. Our results suggest that lithium can be considered as a therapeutic potential for the treatment of some aspects of neuropathic pain and that the opioid system may be involved in the lithium-induced attenuation of thermal hyperalgesia and mechanical allodynia.


Asunto(s)
Modelos Animales de Enfermedad , Cloruro de Litio/uso terapéutico , Antagonistas de Narcóticos/farmacología , Neuralgia/tratamiento farmacológico , Fármacos Neuroprotectores/uso terapéutico , Animales , Conducta Animal/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Hiperalgesia/prevención & control , Cloruro de Litio/administración & dosificación , Cloruro de Litio/antagonistas & inhibidores , Masculino , Naloxona/farmacología , Proteínas del Tejido Nervioso/antagonistas & inhibidores , Neuralgia/metabolismo , Fármacos Neuroprotectores/administración & dosificación , Dimensión del Dolor , Ratas , Ratas Sprague-Dawley , Nervio Ciático/efectos de los fármacos , Nervio Ciático/cirugía
20.
Eur J Pharmacol ; 674(2-3): 260-4, 2012 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-22134003

RESUMEN

Neuropathic pain is caused by a lesion or disease of the somatosensory nervous system and treatment of neuropathic pain remains a challenge. The purpose of the present study was to examine the effect of ethosuximide, an anti-epileptic and relatively selective T-type calcium blocker and morphine, a prototypical opioid in the behavioral responses following the chronic constriction injury (CCI) model of neuropathic pain. Experiments were performed on eight groups (n=8) of male Sprague-Dawley rats (230-280 g). The animals were injected with saline, ethosuximide (100, 200, 300 mg/kg), morphine (4 mg/kg), and a combination of morphine (4 mg/kg) plus ethosuximide (100mg/kg, i.p.). The cold-and mechano-allodynia and thermal hyperalgesia were measured prior to surgery (the day 0) and 3, 5, 7, 14 and 21 days post surgery. Ethosuximide and morphine significantly decreased cold and mechano allodynia and thermal hyperalgesia. However, the co-administration of both drugs seems to be more effective than the ethosuximide or morphine alone on cold and mechano allodynia and thermal hyperalgesia .Our results suggest that ethosuximide block tactile and thermal hypersensitivity after the CCI model, also, ethosuximide potentiates the analgesic effects of morphine in neuropathic pain conditions and behavioral responses.


Asunto(s)
Analgésicos Opioides/farmacología , Bloqueadores de los Canales de Calcio/farmacología , Etosuximida/farmacología , Hiperalgesia/tratamiento farmacológico , Morfina/farmacología , Neuralgia/tratamiento farmacológico , Traumatismos de los Nervios Periféricos/tratamiento farmacológico , Analgésicos Opioides/uso terapéutico , Animales , Bloqueadores de los Canales de Calcio/uso terapéutico , Frío , Constricción , Modelos Animales de Enfermedad , Sinergismo Farmacológico , Etosuximida/uso terapéutico , Calor , Hiperalgesia/etiología , Masculino , Morfina/uso terapéutico , Traumatismos de los Nervios Periféricos/etiología , Ratas , Ratas Sprague-Dawley , Factores de Tiempo
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