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1.
Phys Rev Lett ; 123(21): 214501, 2019 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-31809178

RESUMEN

Some members of the vegetal kingdom can achieve surprisingly fast movements making use of a clever combination of evaporation, elasticity, and cavitation. In this process, enthalpic energy is transformed into elastic energy and suddenly released in a cavitation event which produces kinetic energy. Here, we study this unusual energy transformation by a model system: A droplet in an elastic medium shrinks slowly by diffusion and eventually transforms into a bubble by a rapid cavitation event. The experiments reveal the cavity dynamics over the extremely disparate timescales of the process, spanning 9 orders of magnitude. We model the initial shrinkage as a classical diffusive process, while the sudden bubble growth and oscillations are described using an inertial-(visco)elastic model, in excellent agreement with the experiments. Such a model system could serve as a new paradigm for motile synthetic materials.

2.
World J Urol ; 32(1): 165-72, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23657354

RESUMEN

INTRODUCTION: To evaluate the safety and efficacy of Thulium VapoEnucleation of the prostate (ThuVEP) for patients on oral anticoagulants (OA) with symptomatic benign prostatic obstruction (BPO). METHODS: Fifty-six patients, undergoing ThuVEP at two institutions, were evaluated from May 2009 until June 2011. All patients were at high cardiopulmonary risk and presented with a median American Society of Anesthesiology score of 3 [interquartile range (IQR) 2-3]. Thirty-two patients were on aspirin, 8 were on clopidogrel or clopidogrel and aspirin, and 16 on phenprocoumon at the time of surgery. Patient demographic, perioperative, and follow-up data were analyzed. RESULTS: Median prostate volume was 50 (IQR 34-76) cc, and resected tissue weight was 32 (IQR 20-50) g. The median operative time was 61.5 (IQR 40-100.75) min, and the catheter time 2 (IQR 2-3) days. There were no perioperative thromboembolic events. Five patients (8.9%) required a second-look operation in the immediate postoperative course (hemorrhage n = 4, residual adenoma n = 1) and four (7.1%) blood transfusions. Complications within the first 30 days included urinary tract infections (1.7%), urinary retention (3.6%), and delayed bleeding (7.1%). These complications were managed conservatively. At 12-month follow-up, median QoL [5 (IQR 3.75-5) vs. 1 (IQR 1-2)], IPSS [21.5 (IQR 15.5-23.75) vs. 5 (IQR 3-8)], Qmax [7.7 (IQR 6.3-10) vs. 28.3 (IQR 21.25-39.2) ml/s], and postvoiding residual urine [100 (IQR 46-200) vs. 17.5 (IQR 0-36) ml] improved significantly (p < 0.002). CONCLUSIONS: Thulium VapoEnucleation of the prostate seems to be a safe and efficacious procedure for the treatment of symptomatic BPO in patients at high cardiopulmonary risk on OA.


Asunto(s)
Anticoagulantes/uso terapéutico , Prostatectomía/efectos adversos , Prostatectomía/métodos , Hiperplasia Prostática/cirugía , Tulio , Trombosis de la Vena/prevención & control , Administración Oral , Anciano , Anticoagulantes/administración & dosificación , Aspirina/administración & dosificación , Aspirina/uso terapéutico , Clopidogrel , Hemorragia/epidemiología , Humanos , Incidencia , Masculino , Procedimientos Quirúrgicos Mínimamente Invasivos/efectos adversos , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Estudios Retrospectivos , Ticlopidina/administración & dosificación , Ticlopidina/análogos & derivados , Ticlopidina/uso terapéutico , Resultado del Tratamiento , Infecciones Urinarias/epidemiología
3.
J Voice ; 33(6): 851-859, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30143332

RESUMEN

PURPOSE: The pitch-shift reflex (PSR) is the adaptation of the fundamental frequency during phonation and speech and describes the auditory feedback control. Speakers without voice and speech disorders mostly show a compensation of the pitch change in the auditory feedback and adapt their fundamental frequency to the opposite direction. Dysphonic patients often display problems with the auditory perception and control of their voice during therapy. Our study focuses on the auditory and kinesthetic control mechanisms of patients with muscle tension dysphonia (MTD) and speakers without voice and speech problems. Main purpose of the study is the analysis of the functionality of the control mechanisms within phonation and speech between patients with MTD and normal speakers. METHOD: Sixty-one healthy subjects (17 male, 44 female) and 22 patients with MTD (7 male, 15 female) participated following two paradigms including a sustained phonation (vowel /a/) and speech (['mama]). Within both paradigms the fundamental frequency of the auditory feedback was increased synthetically. For the analysis of the PSR the electroencephalogram, electroglottography, the voice signal, and the high-speed endoscopy data were recorded simultaneously. The PSR in the electroencephalogram was detected via the N100 and the mismatch negativity. Statistical tests were applied for the detection of the PSR in the physiological response within the electroglottography, voice, and high-speed endoscopy signals. The results were compared between both groups. RESULTS: No differences were found between the controls and patients with MTD regarding latency and magnitude of the perception of the pitch shift in both paradigms, but for the magnitude of the behavioral response. Differences also could be found for both groups between the "no pitch" and "pitch" condition of the two paradigms regarding vocal fold dynamics and voice quality. Patients with MTD showed more vibrational irregularities during the PSR than the controls, especially regarding the symmetry of vocal fold dynamics. CONCLUSION: Patients with MTD seem to have a disturbed interaction between the auditory and kinesthetic feedback inducing the execution of an overriding behavioral response.


Asunto(s)
Disfonía/fisiopatología , Retroalimentación Sensorial , Fonación , Percepción de la Altura Tonal , Acústica del Lenguaje , Calidad de la Voz , Adaptación Psicológica , Adulto , Disfonía/diagnóstico , Disfonía/psicología , Femenino , Humanos , Masculino , Tiempo de Reacción , Factores de Tiempo , Adulto Joven
4.
FEBS Lett ; 582(20): 3005-10, 2008 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-18692051

RESUMEN

Translationally controlled tumour protein (TCTP) is involved in malignant transformation and regulation of apoptosis. It has been postulated to serve as a guanine nucleotide exchange factor for the small G-protein Rheb. Rheb functions in the PI3 kinase/mTOR pathway. The study presented here was initiated to characterise the interaction between TCTP and Rheb biochemically. Since (i) no exchange activity of TCTP towards Rheb could be detected in vitro, (ii) no interaction between TCTP and Rheb could be detected by NMR spectroscopy, and (iii) no effect of TCTP depletion in cells on the direct downstream targets of Rheb could be observed in vivo, this study shows that TCTP is unlikely to be a guanine nucleotide exchange factor for Rheb.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Factores de Intercambio de Guanina Nucleótido/metabolismo , Proteínas de Unión al GTP Monoméricas/metabolismo , Neuropéptidos/metabolismo , Proteínas de Unión al GTP rab/metabolismo , Secuencia de Aminoácidos , Animales , Biomarcadores de Tumor/genética , Línea Celular , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Factores de Intercambio de Guanina Nucleótido/genética , Humanos , Datos de Secuencia Molecular , Resonancia Magnética Nuclear Biomolecular , Fosforilación , Interferencia de ARN , Proteína Homóloga de Ras Enriquecida en el Cerebro , Proteínas Quinasas S6 Ribosómicas/metabolismo , Proteína Tumoral Controlada Traslacionalmente 1
5.
J Comp Pathol ; 137(4): 249-252, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17888939

RESUMEN

Three related Grand Basset Griffon Vendéen (GBGV) dogs, two male and one female, with poor locomotion and muscle pain on palpation, were humanely destroyed at approximately 2 months of age and submitted for necropsy. Histopathological examination of skeletal muscles showed hyaline hypereosinophilic myofibres, hypertrophy and atrophy, calcification, necrosis, and mild proliferation of endomyseal connective tissue, as well as small basophilic fibres with internalized nuclei in rows, indicating regeneration. Immunohistochemical labelling for the carboxy-terminal domain of dystrophin, performed on skeletal muscle from one of the male dogs, was negative, whereas it was positive in skeletal muscle from a normal control dog. Both parents were clinically unaffected. These findings confirmed the diagnosis of canine X-linked muscular dystrophy (CXMD). To the authors' knowledge, this is the first report of CXMD in the GBGV breed, and one of very few cases in a female dog.


Asunto(s)
Enfermedades de los Perros/genética , Músculo Esquelético/patología , Distrofia Muscular Animal/genética , Cromosoma X , Animales , Enfermedades de los Perros/metabolismo , Enfermedades de los Perros/patología , Perros , Distrofina/deficiencia , Distrofina/genética , Femenino , Ligamiento Genético , Masculino , Músculo Esquelético/metabolismo , Distrofia Muscular Animal/metabolismo , Distrofia Muscular Animal/patología
6.
J Vet Intern Med ; 20(1): 13-9, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16496918

RESUMEN

Portosystemic shunting occurs frequently either as congenital anomalies of the portal vein (PVA) or as acquired shunting (AS) due to portal hypertension secondary to parenchymal liver disease or portal vein thrombosis. The 2 most commonly used screening tests for portosystemic shunting are bile acid and plasma ammonia concentrations. The purpose of this study was to compare the 12-hour fasting plasma ammonia (AMM) and bile acid concentration (BA) as tests for diagnosing portosystemic shunting. Medical records of 337 dogs were used in which AMM and BA were measured simultaneously and in which portosystemic shunting was confirmed or excluded. These dogs were divided into 2 groups (group 1: portosystemic shunting present, n = 153, and group 2: portosystemic shunting absent, n = 184). Group 1 was subdivided into 2 subgroups (group 1a: PVA, n = 132 and group 1b: AS, n = 21). The sensitivity of AMM in detecting PVA was 100% and of BA was 92.2%. For portosystemic shunting in general (PVA or AS), the sensitivity of AMM was 98% and that of BA was 88.9%. The specificity in the total population of AMM was 89.1% and that of BA was 67.9%. If only dogs with liver diseases were included with (n = 153) or without (n = 28) shunting, the specificity of AMM to detect shunting was 89.3% and that of BA was 17.9%. In conclusion, AMM is a highly sensitive and specific parameter to detect PVA and portosystemic shunting in a general population and in dogs with liver disease, whereas BA is somewhat less sensitive and considerably less specific.


Asunto(s)
Amoníaco/sangre , Ácidos y Sales Biliares/sangre , Enfermedades de los Perros/sangre , Enfermedades de los Perros/diagnóstico , Ayuno/sangre , Derivación Portosistémica Quirúrgica/veterinaria , Animales , Perros , Sensibilidad y Especificidad
8.
Unfallchirurgie ; 17(3): 146-51, 1991 Jun.
Artículo en Alemán | MEDLINE | ID: mdl-1877095

RESUMEN

UNLABELLED: During 1978 to 1987 361 patients (312 female, 49 male) were treated with Variokopf-prosthesis (a bipolar hip prosthesis with a variable head) after femoral neck fracture, per- or subtrochanteric fracture. The mean age was 83 years. During postoperative treatment 73 patients (20.2%) died. 288 could be discharged. 98 of these died before the follow-up examination. The follow-up was possible in 103 cases. A good to satisfactory result was found in 91 cases (88%). A poor result in twelve cases (12%) (Score by Merle d'Aubigne et al.). CONCLUSIONS: 1. The Variokopf-prosthesis is a favourable alternative to a normal hip prosthesis (e.g. Moore), 2. The implantation of a Variokopf-prosthesis was found to be indicated as well in the treatment of medial femoral neck fractures as in special cases in the treatment of per- or subtrochanteric fractures. 3. The operation should be performed soon after the trauma--after a two to three days treatment. 4. The dorsal approach is superior to the lateral in the treatment of hip fractures because of short operating time and the possible early mobilisation of the patients.


Asunto(s)
Fracturas del Cuello Femoral/cirugía , Fracturas de Cadera/cirugía , Prótesis de Cadera , Anciano , Anciano de 80 o más Años , Estudios de Evaluación como Asunto , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Factores de Tiempo
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