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ABSTRACT: Although anxiety and depression have been central topics for scholars and clinicians in the United States, few studies have examined their correlates in sub-Saharan Africa and none have examined large urban slums. Using face-to-face interviews in two African cities, we analyze self-reported symptoms of anxiety and depression in a community-based sample (n = 495). Ordinary least squares regression was used to analyze a variety of demographic and social predictors including sex, child-rearing, marital status, education, income, age, and neighborhood for residents of Agbogbloshie (Accra, Ghana) and Kangemi (Nairobi, Kenya). Controlling for other factors, two personal network dimensions were significant. Total network size is positively associated with symptoms of anxiety and depression in Kenya but not in Ghana. However, one factor was predictive of symptoms of anxiety and depression in both locations: the reported percentage of ties with older persons. Higher levels of anxiety and depression are associated with a larger share of older individuals in one's personal network.
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Ansiedad/etnología , Depresión/etnología , Familia/etnología , Áreas de Pobreza , Características de la Residencia , Red Social , Población Urbana , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Femenino , Ghana/etnología , Humanos , Kenia/etnología , Masculino , Persona de Mediana Edad , Adulto JovenRESUMEN
Relationships with peers are critical for many aspects of adolescent development, including academic outcomes. Incorporating social control, social learning, and social capital theories, we investigated connections between two types of peer networks, close friends and extracurricular activity (ECA) members, and students' own academic performance. Social learning and bonding social capital perspectives posit that close friends should have a symmetrical effect, either beneficial or harmful, because they exert strong influences on adolescents. By contrast, social control and bridging/linking social capital perspectives suggest that ECA member influences should be asymmetrical as they amplify benefits from higher-performing ECA peers and minimize harmful influences from lower-performing ones. We used Add Health data to test our hypotheses. We found that the average friend GPA was positively associated (in the same direction) with student GPA, while ECA member GPAs were, as hypothesized, asymmetrically linked to student GPA. We discussed implications for educators and future research.
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Rendimiento Académico , Capital Social , Adolescente , Amigos , Humanos , Grupo Paritario , EstudiantesRESUMEN
BACKGROUND: Wilson's disease (WD) is an autosomal recessive disorder of copper metabolism resulting in multifaceted neurological, hepatic, and psychiatric symptoms. The objective of the study was to comparatively assess two clinical rating scales for WD, the Unified Wilson's Disease Rating Scale (UWDRS) and the Global Assessment Scale for Wilson's disease (GAS for WD), and to test the feasibility of the patient reported part of the UWDRS neurological subscale (termed the "minimal UWDRS"). METHODS: In this prospective, monocentric, cross-sectional study, 65 patients (median age 35 [range: 15-62] years; 33 female, 32 male) with treated WD were scored according to the two rating scales. RESULTS: The UWDRS neurological subscore correlated with the GAS for WD Tier 2 score (r = 0.80; p < 0.001). Correlations of the UWDRS hepatic subscore and the GAS for WD Tier 1 score with both the Model for End Stage Liver Disease (MELD) score (r = 0.44/r = 0.28; p < 0.001/p = 0.027) and the Child-Pugh score (r = 0.32/r = 0.12; p = 0.015/p = 0.376) were weak. The "minimal UWDRS" score significantly correlated with the UWDRS total score (r = 0.86), the UWDRS neurological subscore (r = 0.89), and the GAS for WD Tier 2 score (r = 0.86). CONCLUSIONS: The UWDRS neurological and psychiatric subscales and the GAS for WD Tier 2 score are valuable tools for the clinical assessment of WD patients. The "minimal UWDRS" is a practical prescreening tool outside scientific trials.
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Degeneración Hepatolenticular/diagnóstico , Pruebas de Función Hepática , Adolescente , Adulto , Cobre/metabolismo , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Adulto JovenRESUMEN
Background: Clinical trials have demonstrated through core and independent studies that anatomical devices are safe and effective with low complication rates. The rotation rate of shaped breast implants in the literature is 0 to 8.2%. Currently there are no studies evaluating the efficacy of in office ultrasound or clinical rotation vs actual rotation rates seen on high-resolution ultrasound (HRUS). Objectives: The purpose of the study is to demonstrate the ease and reliability of HRUS for evaluating the rotation rate of 2 different brands of anatomic implants and to correlate this with the presumed clinical rate, as well as independent evaluators assessments. Methods: A total of 69 patients were followed up at routine intervals and were evaluated for rotation. Any implant rotated past >30° off of midline (outside 5-7 o'clock) was considered to be rotated. To determine if radiographic rotation was clinically evident, 20 composite patient photos were blindly evaluated. Results: A random total of 69 patients underwent bilateral augmentation mammoplasty with form stable anatimic gel implants using 138 implants. Twenty-nine of the 69 (42%) patients and 37 of the 138 (27%) implants were found to be rotated-using HRUS. Eight of the 69 (12%) patients had bilateral rotations. Independent evaluators were able to identify two of 12 (17%) possible rotations, or 2 rotations in 40 (5%) total implants. Conclusions: Anatomic form stable gel implants are actually rotated up to 25 times more frequently than previously thought, but these rotations do not translate into clinically significant sequela. High-resolution ultrasound is a simple alternative for breast implant surveillance and is better accepted by patients than magnetic resonance imaging (MRI). The clinical value of HRUS is also discussed and recommendations for FDA implant labeling changes are provided in this article. Level of Evidence: 4
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Implantación de Mama/instrumentación , Implantes de Mama , Mama/diagnóstico por imagen , Mama/cirugía , Complicaciones Posoperatorias/diagnóstico por imagen , Geles de Silicona , Ultrasonografía Mamaria/métodos , Adulto , Implantación de Mama/efectos adversos , Femenino , Humanos , Interpretación de Imagen Asistida por Computador , Imagenología Tridimensional , Persona de Mediana Edad , Fotograbar , Complicaciones Posoperatorias/etiología , Valor Predictivo de las Pruebas , Estudios Prospectivos , Diseño de Prótesis , Rotación , Factores de Tiempo , Resultado del Tratamiento , Adulto JovenRESUMEN
BACKGROUND AND AIMS: Current guidelines favor the use of chelating agents (d-penicillamine, trientine) in first line therapy of symptomatic Wilson disease patients. Development of chelator induced immunological adverse events are a concern especially under d-penicillamine therapy. This study assessed the prevalence of co-existing or therapy-related immune-mediated diseases in Wilson disease patients, and evaluated the role of antinuclear antibodies in therapy monitoring. METHODS: We retrospectively analyzed 235 Wilson disease patients. Medical regimens were classified and analyzed in relation to adverse events and antinuclear antibody courses. RESULTS: Coexisting immune-mediated diseases were evident in 19/235 (8.1%) patients, of which 13/235 (5.5%) had pre-existing autoimmune diseases. Six patients (2.6%) developed an autoimmune disease under therapy, all of them under long-term d-penicillamine treatment. Data relating to antinuclear antibody courses during treatment and adverse events were available for patients treated with d-penicillamine (n = 91), trientine (n = 58), and zinc salts (n = 58). No significant increase in antinuclear antibody titers in patients treated with d-penicillamine (16/91; 17.6%), trientine (12/58; 20.7%), and zinc (7/58; 12.1%) were found. CONCLUSION: Under long-term d-penicillamine therapy a minority of patients developed immune-mediated disease. Elevations in antinuclear antibodies were found frequently, but no correlations were evident between increases in antinuclear antibodies and the development of immune-mediated diseases or medical regimes. Thus, the value of antinuclear antibodies for monitoring adverse events under chelator therapy seems to be limited.
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Quelantes/efectos adversos , Quelantes/uso terapéutico , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/inmunología , Degeneración Hepatolenticular/tratamiento farmacológico , Degeneración Hepatolenticular/inmunología , Adolescente , Adulto , Anticuerpos Antinucleares/inmunología , Enfermedades Autoinmunes/inducido químicamente , Enfermedades Autoinmunes/inmunología , Niño , Estudios Transversales , Monitoreo de Drogas/métodos , Femenino , Humanos , Masculino , Penicilamina/efectos adversos , Penicilamina/inmunología , Penicilamina/uso terapéutico , Estudios Retrospectivos , Trientina/efectos adversos , Trientina/inmunología , Trientina/uso terapéutico , Adulto Joven , Zinc/efectos adversos , Zinc/inmunología , Zinc/uso terapéuticoRESUMEN
Cis-to-trans isomerization of carbon-carbon double bonds can be induced by the application of mechanical force. Using single molecule force spectroscopy by means of atomic force microscopy (AFM) we pulled polymer molecules which contained cis double bonds in the backbone. In the force versus extension profiles of these polymers, a sudden extension increase is observed which is due to the conversion of shorter cis isomers into longer trans isomers. The added length to the polymer results in relaxation in probed force. We find that the isomerization occurs at forces of 800 ± 60 pN, independent of AFM tip and solid substrate chemistries. Investigation of similar polymers which exclusively contained single bonds in the backbone showed no evidence of a similar transition.
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The primary aim of this study was to develop statistical models to predict peak oxygen consumption (VO2 peak) using OMNI Ratings of Perceived Exertion measured during submaximal cycle ergometry. Male (M = 20.9 yr., SE = 0.4) and female (M = 21.6 yr., SE = 0.5) participants (N = 81) completed a load-incremented maximal cycle ergometer exercise test. Simultaneous multiple linear regression was used to develop separate VO2 peak statistical models using submaximal ratings of perceived exertion for the overall body, legs, and chest/breathing as predictor variables. VO2 peak (L·min(-1)) predicted for men and women from ratings of perceived exertion for the overall body (3.02 ± 0.06; 2.03 ± 0.04), legs (3.02 ± 0.06; 2.04 ± 0.04), and chest/breathing (3.02 ± 0.05; 2.03 ± 0.03) were similar to measured VO2 peak (3.02 ± 0.10; 2.03 ± 0.06, ps > .05). Statistical models based on submaximal OMNI Ratings of Perceived Exertion provide an easily administered and accurate method to predict VO2 peak.
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Ergometría/métodos , Modelos Estadísticos , Consumo de Oxígeno/fisiología , Esfuerzo Físico/fisiología , Adulto , Ciclismo/fisiología , Femenino , Frecuencia Cardíaca/fisiología , Humanos , Masculino , Valor Predictivo de las Pruebas , Autoimagen , Adulto JovenRESUMEN
As transcranial ultrasound stimulation (TUS) advances as a precise, non-invasive neuromodulatory method, there is a need for consistent reporting standards to enable comparison and reproducibility across studies. To this end, the International Transcranial Ultrasonic Stimulation Safety and Standards Consortium (ITRUSST) formed a subcommittee of experts across several domains to review and suggest standardised reporting parameters for low intensity TUS, resulting in the guide presented here. The scope of the guide is limited to reporting the ultrasound aspects of a study. The guide and supplementary material provide a simple checklist covering the reporting of: (1) the transducer and drive system, (2) the drive system settings, (3) the free field acoustic parameters, (4) the pulse timing parameters, (5) in situ estimates of exposure parameters in the brain, and (6) intensity parameters. Detailed explanations for each of the parameters, including discussions on assumptions, measurements, and calculations, are also provided.
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As transcranial ultrasound stimulation (TUS) advances as a precise, non-invasive neuromodulatory method, there is a need for consistent reporting standards to enable comparison and reproducibility across studies. To this end, the International Transcranial Ultrasonic Stimulation Safety and Standards Consortium (ITRUSST) formed a subcommittee of experts across several domains to review and suggest standardised reporting parameters for low intensity TUS, resulting in the guide presented here. The scope of the guide is limited to reporting the ultrasound aspects of a study. The guide and supplementary material provide a simple checklist covering the reporting of: (1) the transducer and drive system, (2) the drive system settings, (3) the free field acoustic parameters, (4) the pulse timing parameters, (5) in situ estimates of exposure parameters in the brain, and (6) intensity parameters. Detailed explanations for each of the parameters, including discussions on assumptions, measurements, and calculations, are also provided.
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Consenso , Humanos , Encéfalo/fisiología , Encéfalo/diagnóstico por imagen , Terapia por Ultrasonido/normas , Terapia por Ultrasonido/métodosRESUMEN
Adaptations to resistance training and subsequent performance can be undermined by inadequate interset recovery. Methods typically used to monitor recovery were developed for longitudinal use, making them time-inefficient within singular exercise bouts. If valid, perceptual recovery status (PRS) may be used as an efficient and inexpensive assessment tool to monitor individual recovery. PURPOSE: The aim of this study was to assess the validity of PRS on monitoring recovery during a high-intensity back-squat session. METHODS: Ten healthy men participated in the 2-session study (separated by at least 48 h). Session 1 included anthropometrics, PRS familiarization, and a 1-repetition-maximum back squat. Session 2 included a high-intensity protocol (5 sets of 5 repetitions; 5-min interset recovery; 85% of 1-repetition maximum). PRS was obtained before the first set and during the last 30 seconds of each 5-minute recovery; rating of perceived exertion (RPE) was also collected. A linear position transducer collected mean barbell velocity (MBV). Repeated-measures correlations assessed the common intraindividual relationships of PRS scores to intraset MBV and RPE, respectively. RESULTS: A very large, positive correlation appeared between PRS and MBV (r [95% CI] = .778 [.613 to .878]; P < .0001). A large, negative correlation emerged between PRS and RPE (r [95% CI] = -.549 [-.737 to -.282]; P < .001). CONCLUSIONS: Results indicate that PRS can be a means for practitioners to monitor individualized recovery. PRS tracked well with RPE, strengthening its utility in a practitioner-based setting. Findings provide insight into the practicality of PRS for recovery monitoring. It could be used alongside other measures (eg, MBV and countermovement jump) to individually program and maintain performance.
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Ejercicio Físico , Entrenamiento de Fuerza , Masculino , Humanos , Postura , Entrenamiento de Fuerza/métodosRESUMEN
BACKGROUND AND PURPOSE: We aimed to evaluate safety and tolerability of a novel operator-independent ultrasound device among stroke-free volunteers. METHODS: A headframe containing 18 ultrasound transducers (each operating at 2 MHz, pulsed-wave) was used to expose both temporal windows and the suboccipital window. The transmission characteristics were set to emulate the acoustic characteristics of the exposure levels in the Combined Lysis of Thrombus in Brain Ischemia using Transcranial Ultrasound and Systemic tPA (CLOTBUST) trial and to never exceed Food and Drug Administration mandated diagnostic ultrasound exposure limits. Volunteers underwent 2 hours of insonation with transducer activation one at a time. Safety was captured using serial neurological examinations and pre- and postinsonation MRI for detection of the blood brain barrier permeability. RESULTS: A total of 15 volunteers (40% men; 49 ± 16 years; 27% black; all pre-exposure National Institutes of Health Stroke Scale scores 0) were enrolled. Five volunteers received pulsed-wave ultrasound via the best pair temporal transducers, 5 via sequential activation of the suboccipital transducers, and 5 via sequential activation of all bilateral temporal and suboccipital transducers. All subjects were safely insonated with no adverse effects as indicated by the neurological examinations during, immediately after the exposure, and at 24 hours, and no abnormality of the blood brain barrier was found on any of the MRIs. CONCLUSIONS: Our novel device was well tolerated by stroke-free volunteers and did not cause any neurological dysfunction nor did it affect blood brain barrier integrity. The safety and efficacy of the device are now being tested in stroke patients receiving intravenous tissue-type plasminogen activator in phase II-III clinical trials.
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Trombosis Intracraneal/terapia , Accidente Cerebrovascular/terapia , Terapia Trombolítica/instrumentación , Terapia por Ultrasonido/instrumentación , Adulto , Anciano , Barrera Hematoencefálica/patología , Encéfalo/patología , Seguridad de Equipos , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Trombolisis Mecánica/instrumentación , Trombolisis Mecánica/métodos , Persona de Mediana Edad , Terapia Trombolítica/métodos , Terapia por Ultrasonido/métodosRESUMEN
BACKGROUND & AIMS: Wilson disease is a genetic copper storage disorder that causes hepatic and neurologic symptoms. Chelating agents (D-penicillamine, trientine) are used as first-line therapies for symptomatic patients, but there are few data from large cohorts. We assessed the safety of D-penicillamine and trientine therapy and outcomes of patients with Wilson disease. METHODS: We performed a retrospective analysis of data on 380 patients with Wilson disease from tertiary care centers in Germany and Austria, and 25 additional patients from the EUROWILSON registry. Chelator-based treatment regimens were analyzed for their effect on neurologic and hepatic symptoms and for adverse events that led to discontinuation of therapy (Kaplan-Meier estimation; data were collected for a mean of 13.3 y after therapy began). RESULTS: Changes in medication were common, resulting in analysis of 471 chelator monotherapies (326 patients receiving D-penicillamine and 141 receiving trientine). Nine of 326 patients treated with D-penicillamine and 3 of 141 patients given trientine underwent liver transplantation. Adverse events leading to discontinuation of treatment were more frequent among those receiving D-penicillamine than trientine (P = .039). Forty-eight months after therapy, hepatic deterioration was reported in only 4 of 333 patients treated initially with a chelating agent. Hepatic improvements were observed in more than 90%, and neurologic improvements were observed in more than 55%, of therapy-naive patients, and values did not differ significantly between treatments. However, neurologic deterioration was observed less frequently in patients given D-penicillamine first (6 of 295) than those given trientine first (4 of 38; P = .018). CONCLUSIONS: Chelating agents are effective therapies for most patients with Wilson disease; D-penicillamine and trientine produce comparable outcomes, although D-penicillamine had a higher rate of adverse events. Few patients receiving chelation therapy had neurologic deterioration, which occurred more frequently in patients who received trientine.
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Quelantes/administración & dosificación , Quelantes/efectos adversos , Degeneración Hepatolenticular/tratamiento farmacológico , Penicilamina/administración & dosificación , Penicilamina/efectos adversos , Trientina/administración & dosificación , Trientina/efectos adversos , Adolescente , Adulto , Austria , Niño , Preescolar , Estudios de Cohortes , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/epidemiología , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/patología , Femenino , Alemania , Degeneración Hepatolenticular/patología , Humanos , Lactante , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento , Adulto JovenRESUMEN
BACKGROUND: Wilson disease (WD) is an autosomal recessive copper storage disease resulting in hepatic and neurologic dysfunction. Liver transplantation is an effective treatment for fulminant cases for patients with chronic liver disease. Reports on the outcome of neuropsychiatric symptoms after orthotopic liver transplantation (OLT) are limited. AIM: To assess the course of neuropsychiatric and hepatic symptoms after liver transplantation for Wilson disease METHODS: Nineteen patients with Wilson disease received liver transplantation and were followed prospectively from 2005 to 2010 for the development of hepatic, neurological and psychiatric symptoms. RESULTS: Eight patients (all female) were transplanted for acute liver failure and eleven patients for chronic liver failure. Patient survival rates one and five yr after transplantation were 78% and 65%, respectively. Of the surviving patients, hepatic symptom scores improved in all patients and neurological symptom scores improved in all but one patient after OLT compared to the time of initial diagnosis and compared to pre-OLT status. Psychiatric symptoms showed moderate improvements. CONCLUSION: Survival after OLT for Wilson disease with end-stage liver disease is excellent. Overall, neuropsychiatric symptoms improved after transplantation, substantiating arguments for widening of the indication for liver transplantation in symptomatic neurologic Wilson disease patients with stable liver function.
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Degeneración Hepatolenticular/cirugía , Trasplante de Hígado , Enfermedades del Sistema Nervioso/etiología , Complicaciones Posoperatorias , Adolescente , Adulto , Femenino , Estudios de Seguimiento , Supervivencia de Injerto , Degeneración Hepatolenticular/mortalidad , Humanos , Enfermedades del Sistema Nervioso/diagnóstico , Enfermedades del Sistema Nervioso/fisiopatología , Pruebas Neuropsicológicas , Pronóstico , Estudios Prospectivos , Estudios Retrospectivos , Factores de Riesgo , Adulto JovenRESUMEN
This article examines the challenges associated with making acoustic output measurements at high ultrasound frequencies (>20 MHz) in the context of regulatory considerations contained in the US Food and Drug Administration industry guidance document for diagnostic ultrasound devices. Error sources in the acoustic measurement, including hydrophone calibration and spatial averaging, nonlinear distortion, and mechanical alignment, are evaluated, and the limitations of currently available acoustic measurement instruments are discussed. An uncertainty analysis of acoustic intensity and power measurements is presented, and an example uncertainty calculation is done on a hypothetical 30-MHz high-frequency ultrasound system. This analysis concludes that the estimated measurement uncertainty of the acoustic intensity is +73%/-86%, and the uncertainty in the mechanical index is +37%/-43%. These values exceed the respective levels in the Food and Drug Administration guidance document of 30% and 15%, respectively, which are more representative of the measurement uncertainty associated with characterizing lower-frequency ultrasound systems. Recommendations made for minimizing the measurement uncertainty include implementing a mechanical positioning system that has sufficient repeatability and precision, reconstructing the time-pressure waveform via deconvolution using the hydrophone frequency response, and correcting for hydrophone spatial averaging.
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Artefactos , Diagnóstico por Imagen de Elasticidad/normas , Regulación Gubernamental , Aumento de la Imagen/normas , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Estados UnidosRESUMEN
PURPOSE: Acoustic peak rarefaction pressure (APRP) is the main factor that influences ultrasound-enhanced thrombolysis. We sought to determine whether recanalization rate and functional outcomes in the Transcranial Ultrasound in Clinical SONothrombolysis (TUCSON) trial could be predicted by estimated in vivo APRP. METHODS: We developed an acoustic attenuation model to estimate the in vivo APRP at the arterial occlusion site in each subject of the TUCSON trial with CT scans eligible for measurements. Variables included temporal bone thickness, depth of arterial occlusion site, and average attenuation of skin and brain tissues. Recanalization was defined as partial or complete using the Thrombolysis in Brain Infarction flow grades. Functional independence was assessed at 3 months using the modified Rankin Scale score (mRS, 0-1). RESULTS: APRP was calculated in 20 acute ischemic stroke patients treated with sonothrombolysis (mean age, 64 ± 15 years, 65% men; median NIHSS score, 13; IQR, 6-17). The mean APRP was 30.2 ± 15.5 kPa (range, 8-68 kPa). Patients with persisting occlusion had nonsignificantly lower APRP than patients with partial or complete recanalization (25.2 ± 8.0 versus 32.3 ± 17.7 kPa; p = 0.228). Patients who were functionally independent at 3 months had nonsignificantly higher APRP than patients with worse outcome (35.1 ± 19.5 versus 25.9 ± 11.2 kPa; p = 0.217). CONCLUSIONS: Our exploratory analysis suggests a potentially important role of successful energy delivery to augment thrombolysis with 2-MHz ultrasound in acute ischemic stroke patients.
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Infarto Cerebral/diagnóstico por imagen , Trombolisis Mecánica/métodos , Ultrasonografía Doppler Transcraneal , Ultrasonografía Intervencional , Anciano , Fenómenos Biomecánicos , Infarto Cerebral/terapia , Terapia Combinada , Femenino , Fibrinolíticos/uso terapéutico , Estudios de Seguimiento , Humanos , Modelos Logísticos , Masculino , Microesferas , Persona de Mediana Edad , Modelos Biológicos , Presión , Recuperación de la Función , Estudios Retrospectivos , Método Simple Ciego , Terapia Trombolítica/métodos , Activador de Tejido Plasminógeno/uso terapéutico , Tomografía Computarizada por Rayos X , Resultado del TratamientoRESUMEN
BACKGROUND: Nonfocused externally applied ultrasound energy has been used extensively in the clinical setting for noninvasive body contouring on the premise that ultrasonic diathermy may have a reducing effect on adipose tissue. OBJECTIVES: The authors document both the time/temperature relationships and cellular changes following nonfocused and weakly focused ultrasound treatments in an animal model. METHODS: Nonfocused ultrasound treatments were administered to 3 Yorkshire pigs, at clinically recommended settings, for two 12-minute intervals. Tissue temperatures were recorded. Lymph fluid samples were taken pretreatment from the control side and posttreatment from the treated side. Biopsies were taken of the skin, adipose tissue, muscle, and lymph nodes on both the control side (pretreatment) and the ultrasound-treated side (posttreatment) for histological examination. RESULTS: Lymph fluid analysis revealed highly elevated triglyceride values on the treated side versus the control. Analysis of lymph node biopsies revealed free vacuoles of fat within the lymph node tissue on the treated side compared with normal controls. In situ temperature measurements indicated that the device produced uniform heating throughout the adipose tissue layer. Electron microscopy of the treated adipose tissue revealed alterations in the cellular architecture without necrosis and free lipids within the extracellular space. CONCLUSIONS: On the basis of the increase of free lipids in the lymph system posttreatment, the increase in free lipids within the lymph nodes on the treated side, and the free lipids in the extracellular space without cell necrosis, we conclude that treatment with this device reduces adipose tissue by altering the permeability of the adipocytes.
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Adipocitos/efectos de la radiación , Temperatura Corporal/efectos de la radiación , Lipectomía/instrumentación , Terapia por Ultrasonido/instrumentación , Adipocitos/patología , Animales , PorcinosRESUMEN
BACKGROUND: Although clinical evidence of successful autologous fat transfer (AFT) using third-generation ultrasound-assisted liposuction (UAL) is readily available, no study has quantified adipocyte viability using standardized methods. OBJECTIVES: The authors assess acute adipocyte viability following fat aspiration as a first step in determining the overall efficacy of using third-generation UAL for AFT. METHODS: Lipoaspirate samples were collected from patients who underwent elective liposuction procedures at multiple surgery centers. Patients with a history of bleeding disorders, diabetes, human immunodeficiency virus, or lipoatrophy disorders were excluded. The UAL system (VASER; Sound Surgical Technologies, Inc, Louisville, Colorado) was set at 60% amplitude in pulsed mode with vacuum aspiration of 15 in Hg or less. Laboratory analysis included free lipid volume, viability via lipolysis and propidium iodide staining, and cytological analysis, including cell surface protein examination and hematoxylin and eosin staining. RESULTS: The lipolysis assay revealed metabolically active adipocytes with a mean (SD) correlative viability of 85.1% (11%). Direct measures of acute viability via propidium iodide staining resulted in a mean (SD) viability measure of 88.7% (3.5%). Both mean values are within the historical range reported from syringe and vacuum-assisted lipoaspiration. Aqueous and lipid contents were favorably reduced after washing and filtering (Puregraft system; Cytori Therapeutics, Inc, San Diego, California). Cellular phenotypes identified were primarily white blood cells or vascular endothelial and vascular associated cells. CONCLUSIONS: Adipose tissue acquired via third-generation UAL is viable at harvest and is potentially a suitable source for autologous fat grafts. These results confirm reported clinical successes utilizing third-generation ultrasound lipoaspirate for AFT.
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Adipocitos/fisiología , Tejido Adiposo/trasplante , Lipectomía/métodos , Terapia por Ultrasonido/métodos , Adipocitos/trasplante , Tejido Adiposo/diagnóstico por imagen , Tejido Adiposo/patología , Adulto , Biopsia con Aguja , Supervivencia Celular/fisiología , Femenino , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Muestreo , Recolección de Tejidos y Órganos/métodos , Trasplante Autólogo , Resultado del Tratamiento , Ultrasonografía , Adulto JovenRESUMEN
This article is a review of the techniques for characterizing ultrasound surgical devices, as a guide to those undertaking a program of measurement, and as a basis for further standardization of those methods. The review covers both acoustic and nonacoustic measurements, with an emphasis on proper techniques, devices, and analyses according to the IEC Standard 61847. Low-frequency hydrophone measurements are presented, which are centered on simple acoustic theory. Inertial cavitation measurements are described based on detailed analyses of shock wave propagation. Cutting force tests are also presented as a basis for determining relative performance characteristics and determining mechanisms of action. Example data from each type of test are given. Comparison between acoustic output measurements, in vitro data, and clinical outcomes help establish that inertial cavitation is the predominant mechanism of soft tissue erosion and emulsification. The test results also demonstrate approaches to improving efficiency while minimizing undesired effects. Finally, recommendations are made for updates to the 61847 Standard and for other device labeling that would improve patient safety.
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Equipo Quirúrgico , Ultrasonido , Humanos , Ultrasonido/instrumentaciónRESUMEN
This quasi-experimental study evaluated the impact of a 10-week evidence-based falls prevention program (Bingocize®) on self-reported fear of falling, general health, physical activity, social isolation, and avoidance behavior, in community-dwelling older adults in Virginia. Participants > 60 years of age (n= 481) attended BingocizeR group sessions twice per week for 10 weeks. The program combined conventional bingo with periodic strength, balance, flexibility exercises, and fall prevention education. Pre and post assessments gauged participants' self-perception of fear of falling, general health, physical activity, social isolation, and avoidance behavior. 481 participants attended at least 80% of the sessions. Following the intervention, paired sample t-tests revealed statistically significant improvements (p <.05) in fear of falling, physical activity, social isolation, avoidance behavior, and yet there was no notable change in self-reported general health. The 10-week BingocizeR program appears to improve physical activity, social isolation, avoidance behavior, and fear of falling. Self-reported general health did not significantly change.
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The primary purpose of this work was to design and implement a compact, battery-powered, fully wearable applicator for delivering therapeutic low-frequency (20-40kHz), low-intensity (100mW/cm2 ISPTP) (LFLI) ultrasound to enable treatment of chronic wounds in home setting. Such a device does not currently exist, and in addition to engineering aspects associated with electromechanical design, its implementation requires a novel approach involving consideration of feedback received not only from healthcare professionals, but also caregivers. One strong motivation for the novel design approach is to enable individuals with chronic wounds to enhance self-care management of wounds in the home setting instead of a hospital or outpatient clinic setting. In the home setting, the device may be exposed to physical maltreatment, requiring precautions with respect to its sturdiness. Although the holistic approach presented have been applied to the design of an applicator for chronic wounds, the design considerations and execution are transferable to any device targeted for home use. The implementation exemplified here examines transformation of an early, relatively fragile design into a robust, time-programmable, safe tool. The modification, which includes comprehensive reconfiguration and redesign of the electronics driving a piezoelectric transducer is presented along with methodology devised with the field feedback obtained from focus groups. This feedback evinced that in addition to electrical engineering, an extensive background in mechanical engineering, material science, biology, and clinical practice is needed to fabricate an end-user friendly, quality-of-life improving, ergonomic device.