Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 13 de 13
Filtrar
1.
Phys Rev E ; 107(2-2): 025303, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36932550

RESUMEN

The goal of this work is to advance the characteristics of existing lattice Boltzmann Dirichlet velocity boundary schemes in terms of the accuracy, locality, stability, and mass conservation for arbitrarily grid-inclined straight walls, curved surfaces, and narrow fluid gaps, for both creeping and inertial flow regimes. We reach this objective with two infinite-member boundary classes: (1) the single-node "Linear Plus" (LI^{+}) and (2) the two-node "Extended Multireflection" (EMR). The LI^{+} unifies all directional rules relying on the linear combinations of up to three pre- or postcollision populations, including their "ghost-node" interpolations and adjustable nonequilibrium approximations. On this basis, we propose three groups of LI^{+} nonequilibrium local corrections: (1) the LI_{1}^{+} is parametrized, meaning that its steady-state solution is physically consistent: the momentum accuracy is viscosity-independent in Stokes flow, and it is fixed by the Reynolds number (Re) in inertial flow; (2) the LI_{3}^{+} is parametrized, exact for arbitrary grid-rotated Poiseuille force-driven Stokes flow and thus most accurate in porous flow; and (3) the LI_{4}^{+} is parametrized, exact for pressure and inertial term gradients, and hence advantageous in very narrow porous gaps and at higher Reynolds range. The directional, two-relaxation-time collision operator plays a crucial role for all these features, but also for efficiency and robustness of the boundary schemes due to a proposed nonequilibrium linear stability criterion which reliably delineates their suitable coefficients and relaxation space. Our methodology allows one to improve any directional rule for Stokes or Navier-Stokes accuracy, but their parametrization is not guaranteed. In this context, the parametrized two-node EMR class enlarges the single-node schemes to match exactness in a grid-rotated linear Couette flow modeled with an equilibrium distribution designed for the Navier-Stokes equation (NSE). However, exactness of a grid-rotated Poiseuille NSE flow requires us to perform (1) the modification of the standard NSE term for exact bulk solvability and (2) the EMR extension towards the third neighbor node. A unique relaxation and equilibrium exact configuration for grid-rotated Poiseuille NSE flow allows us to classify the Galilean invariance characteristics of the boundary schemes without any bulk interference; in turn, its truncated solution suggests how, when increasing the Reynolds number, to avoid a deterioration of the mass-leakage rate and momentum accuracy due to a specific Reynolds scaling of the kinetic relaxation collision rate. The optimal schemes and strategies for creeping and inertial regimes are then singled out through a series of numerical tests, such as grid-rotated channels and rotated Couette flow with wall-normal injection, cylindrical porous array, and Couette flow between concentric cylinders, also comparing them against circular-shape fitted FEM solutions.

2.
Phys Rev E ; 103(5-1): 053308, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-34134275

RESUMEN

We propose a procedure to implement Dirichlet velocity boundary conditions for complex shapes that use data from a single node only, in the context of the lattice Boltzmann method. Two ideas are at the base of this approach. The first is to generalize the geometrical description of boundary conditions combining bounce-back rule with interpolations. The second is to enhance them by limiting the interpolation extension to the proximity of the boundary. Despite its local nature, the resulting method exhibits second-order convergence for the velocity field and shows similar or better accuracy than the well-established Bouzidi's scheme for curved walls [M. Bouzidi, M. Firdaouss, and P. Lallemand, Phys. Fluids 13, 3452 (2001)]PHFLE61070-663110.1063/1.1399290. Among the infinite number of possibilities, we identify several meaningful variants of the method, discerned by their approximation of the second-order nonequilibrium terms and their interpolation coefficients. For each one, we provide two parametrized versions that produce viscosity independent accuracy at steady state. The method proves to be suitable to simulate moving rigid objects or surfaces moving following either the rigid body dynamics or a prescribed kinematic. Also, it applies uniformly and without modifications in the whole domain for any shape, including corners, narrow gaps, or any other singular geometry.

3.
J Clin Med ; 10(7)2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-33915856

RESUMEN

BACKGROUND: the aim of this study was to perform an Italian telematics survey analysis on the changes in couples' sex lives during the coronavirus disease 2019 (COVID-19) lockdown. METHODS: a multicenter cross sectional study was conducted on people sexually active and in stable relationships for at least 6 months. To evaluate male and female sexual dysfunctions, we used the international index of erectile function (IIEF-15) and the female sexual function index (FSFI), respectively; marital quality and stability were evaluated by the marital adjustment test (items 10-15); to evaluate the severity of anxiety symptoms, we used the Hamilton Anxiety Rating Scale. The effects of the quarantine on couples' relationships was assessed with questions created in-house. RESULTS: we included 2149 participants. The sex lives improved for 49% of participants, particularly those in cohabitation; for 29% it deteriorated, while for 22% of participants it did not change. Women who responded that their sex lives deteriorated had no sexual dysfunction, but they had anxiety, tension, fear, and insomnia. Contrarily, men who reported deteriorating sex lives had erectile dysfunctions and orgasmic disorders. In both genders, being unemployed or smart working, or having sons were risk factors for worsening the couples' sex lives. CONCLUSION: this study should encourage evaluation of the long-term effects of COVID-19 on the sex lives of couples.

4.
Urologia ; 84(2): 109-112, 2017 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-27886351

RESUMEN

INTRODUCTION: Primary female bladder neck obstruction is a rare clinical condition characterized by the absence/incomplete bladder neck opening during the voiding phase of micturition. METHODS: We present the cases of two women complaining dysuria, abdominal straining and sensation of incomplete bladder emptying. Videourodynamic evaluation was fundamental for a correct diagnosis. RESULTS: Videourodynamic evaluation showed a high detrusor pressure during emptying phase, partial use of abdominal strain, very low urine flow rate and significant postvoid residual; imaging showed a defect in the physiological funneling of the bladder neck, absent or incomplete. The first step therapy is represented by oral alpha-blockers and clean intermittent self-catheterization in case of high postvoid residual. Surgical operations, such as bladder neck incision and resection, represent the last option. CONCLUSIONS: In our experience, bladder neck obstruction is a rare condition in women and only a complete clinical evaluation associated with videourodynamic study can lead to an appropriate diagnosis and treatment.


Asunto(s)
Obstrucción del Cuello de la Vejiga Urinaria/diagnóstico , Urodinámica , Grabación en Video , Adulto , Técnicas de Diagnóstico Urológico , Femenino , Humanos , Persona de Mediana Edad , Obstrucción del Cuello de la Vejiga Urinaria/fisiopatología
5.
J Endourol ; 31(1): 72-77, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27869504

RESUMEN

PURPOSE: We sought to test the content validity of a new training model for flexible ureteroscopy: the Key-Box. MATERIAL AND METHODS: Sixteen medical students were randomized to undergo a 10-day training consisting of performing 10 different exercises aimed at learning specific movements with the flexible ureteroscope, and how to catch and release stones with a nitinol basket using the Key-Box (n = 8 students in the training group, n = 8 students in the nontraining control group). Subsequently, an expert endourologist (O.T.) blindly assessed skills acquired by the whole cohort of students through two exercises on ureteroscope manipulation and one exercise on stone capture selected among those used for the training. A performance scale (1-5) assessing different steps of the procedure was used to evaluate each student. Time to complete the exercises was measured. Mann-Whitney Rank Sum test was used for comparisons between the two groups. RESULTS: Mean scores obtained by trained students were significantly higher compared with those obtained by nontrained students (all p < 0.001). All trained students were able to complete the two exercises on ureteroscope manipulation within 3 minutes, whereas two students (25%) were not able to finish the exercise on stone capture. Conversely, four (50%) and six (75%) nontrained students were not able to finish one out of the two exercises on ureteroscope manipulation and the exercise on stone capture, respectively. The mean time to complete the three exercises was 76.3, 69.9, and 107 and 172.5, 137.9, and 168 seconds in the trained and nontrained groups, respectively (all p < 0.001). CONCLUSIONS: The K-Box® seems to be a valid easy-to-use training model for initiating novel endoscopists to flexible ureteroscopy.


Asunto(s)
Educación de Postgrado en Medicina , Entrenamiento Simulado , Ureteroscopios , Ureteroscopía/educación , Ureteroscopía/métodos , Curriculum , Diseño de Equipo , Humanos , Reproducibilidad de los Resultados , Estudiantes de Medicina , Ureteroscopía/instrumentación , Adulto Joven
7.
Arch Ital Urol Androl ; 88(4): 266-269, 2016 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-28073190

RESUMEN

OBJECTIVE: Endometriosis is an estrogendependent disease. The incidence of urinary tract endometriosis (UE) increased during the last few years and, nowadays, it ranges from 0.3 to 12% of all women affected by the disease. The ureter is the second most common site affected. The ureteral endometriosis is classified in extrinsic and intrinsic. The aim of this study is to individuate the best treatments for each subset of ureteral endometriosis. MATERIALS AND METHODS: 32 patients diagnosed with surgically treated UE were retrospectively reviewed. The patients were divided into 3 subsets (intrinsic UE, extrinsic UE with and without obstruction). The patients with intrinsic UE (n = 10) were treated with laser endoureterotomy. The patients with extrinsic UE (n = 22) were divided in two subsets with (n = 16) and without (n = 6) hydronephrosis. All the patients underwent ureteral stenting, and resection and reimplantation was performed in the first group, and when the mass was > 2.5 cm (n = 3) Boari flap was performed. Laparoscopic ureterolysis (shaving) was performed in the second group. RESULTS: In the extrinsic subset of UE, we obtained an high therapeutic success (84%). Conversely, in the intrinsic subset there was a recurrence rate of the disease in 6/10 of the patients (60%). CONCLUSIONS: Ureterolysis seems to be a good treatment in extrinsic UE without obstruction. Resection and reimplantation allows excellent results in the extrinsic UE with obstruction. In the intrinsic subset, the endoureterotomy approach is inadequate.


Asunto(s)
Endometriosis/cirugía , Enfermedades Ureterales/cirugía , Adulto , Endometriosis/clasificación , Femenino , Humanos , Persona de Mediana Edad , Estudios Retrospectivos , Enfermedades Ureterales/clasificación , Procedimientos Quirúrgicos Urológicos
8.
J Endourol ; 30(1): 49-55, 2016 01.
Artículo en Inglés | MEDLINE | ID: mdl-26381037

RESUMEN

BACKGROUND AND PURPOSE: Flexible ureterorenoscopy (F-URS) plays a major role in the management of kidney stones. Ureteral access sheaths (UAS) are important tools for F-URS. In this study, we aimed to evaluate the difference in intrarenal pressures between different flexible ureteroscopes while using the same UAS and to calculate the irrigation flow variance. MATERIALS AND METHODS: Eight different flexible ureteroscopes were tested with five different UAS on an artificial kidney model to measure intrarenal pressures and irrigation flow. Irrigation at 60 cmH2O pressure was performed; the pressure and the irrigation flow amount were recorded with different states of the operator channel: Free, with the laser fiber (272 µm), and with the nitinol basket (1.9F) inside. RESULTS: The highest pressure recorded was 46.68 cmH2O with Wolf Boa and 9.5/11.5F Cook Medical UAS. All the ureteroscopes that fit inside the 10/12F Coloplast ReTrace provided pressures below 40 cmH2O. The inner diameter of the 10/12F Rocamed Bi-Flex is actually 11F, so intrarenal pressures were lower and irrigation flow was higher. With the 11/13F Boston Scientific Navigator HD and 12/14F Coloplast ReTrace, the pressures were very low. The irrigation flow measurements were in concordance with pressure measurements. CONCLUSION: The ureteroscope sizes diminished with advancements in technology. Small-sized ureteroscopes can provide low intrarenal pressures with good irrigation flow when used with convenient small-sized access sheaths. The compatibility between the ureteroscopes and UASs should be anticipated by all endourologists and considered during F-URS. The advantages of 10/12 UASs in terms of intrarenal pressure and irrigational flow should make these access sheaths an interesting first-line choice.


Asunto(s)
Diseño de Equipo , Cálculos Renales/cirugía , Riñón/cirugía , Presión , Ureteroscopios , Ureteroscopía/métodos , Humanos , Irrigación Terapéutica
9.
Urologia ; 82(1): 1-9, 2015.
Artículo en Italiano | MEDLINE | ID: mdl-25589028

RESUMEN

Female urinary incontinence represents a medical and social problem with huge impact regarding both patient's quality of life and social costs. The diagnosis is important for therapeutic choice and should consider some factors: the degree of urethral mobility, urodynamics parameters, patient's will and expectations, information about surgical complications and risks. Nowadays suburethral sling evolution and bulking therapy for selected cases consent to perform miniinvasive surgery; the most relevant problem concerns the management of postoperative complications: in this sense autologous slings are used after urethrolisis. In most difficult cases, it is possible to consider artificial sphincter as the best option.


Asunto(s)
Calidad de Vida , Cabestrillo Suburetral , Incontinencia Urinaria de Esfuerzo/cirugía , Medicina Basada en la Evidencia , Femenino , Humanos , Resultado del Tratamiento , Procedimientos Quirúrgicos Urológicos
10.
J Urol ; 190(3): 857-62, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23545101

RESUMEN

PURPOSE: Bacillus Calmette-Guérin and intravesical chemotherapy represent viable adjuvant options for intermediate risk nonmuscle invasive bladder cancer. Although bacillus Calmette-Guérin is perceived as less tolerable than intravesical chemotherapy, to our knowledge no comparative studies have addressed quality of life issues. We compared the quality of life of patients with nonmuscle invasive bladder cancer who received adjuvant intravesical gemcitabine or 1/3 dose bacillus Calmette-Guérin. MATERIALS AND METHODS: Our multicenter, prospective, randomized, phase II study included 120 patients with intermediate risk nonmuscle invasive bladder cancer. Of these patients 88 remained assessable at 1-year followup. Only 1 patient was withdrawn because of adverse events. Overall 61 patients received 2,000 mg/50 cc gemcitabine weekly for 6 weeks (maintenance monthly for 1 year) while 59 received 1/3 dose bacillus Calmette-Guérin Connaught weekly for 6 weeks (maintenance 3 weekly instillations at 3, 6 and 12 months). Quality of life was measured by the EORTC QLQ-C30 (European Organization for the Research and Treatment of Cancer Quality of Life Questionnaire Core 30 version 3.0) and QLQ-BLS24 (Quality of Life Superficial Bladder Cancer-Specific 24) questionnaires. Group differences were calculated using ANOVA (ANOVA/MANOVA). RESULTS: Treatment was well tolerated in both groups, although local and systemic side effects were more frequently reported in the bacillus Calmette-Guérin arm. Multivariate analyses showed no significant differences between the 2 groups in all quality of life dimensions. No significant changes over time in quality of life domains were detected for patients on bacillus Calmette-Guérin and gemcitabine except for physical functioning, which decreased significantly in both groups (p = 0.002). No significant differences were detected in terms of recurrence and progression between the 2 groups at 1-year followup. CONCLUSIONS: While a higher rate of side effects, albeit mild to moderate, was detected with 1/3 dose bacillus Calmette-Guérin compared to gemcitabine, our study failed to show significant differences between the 2 drugs in terms of quality of life.


Asunto(s)
Vacuna BCG/administración & dosificación , Carcinoma de Células Transicionales/tratamiento farmacológico , Desoxicitidina/análogos & derivados , Recurrencia Local de Neoplasia/mortalidad , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Administración Intravesical , Vacuna BCG/efectos adversos , Carcinoma de Células Transicionales/mortalidad , Carcinoma de Células Transicionales/patología , Desoxicitidina/administración & dosificación , Desoxicitidina/efectos adversos , Supervivencia sin Enfermedad , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Femenino , Estudios de Seguimiento , Humanos , Estimación de Kaplan-Meier , Masculino , Análisis Multivariante , Invasividad Neoplásica/patología , Recurrencia Local de Neoplasia/patología , Recurrencia Local de Neoplasia/terapia , Estadificación de Neoplasias , Estudios Prospectivos , Calidad de Vida , Medición de Riesgo , Análisis de Supervivencia , Resultado del Tratamiento , Neoplasias de la Vejiga Urinaria/mortalidad , Neoplasias de la Vejiga Urinaria/patología , Gemcitabina
11.
Scand J Urol ; 47(2): 158-62, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23035712

RESUMEN

OBJECTIVE: Leiomyomata are benign neoplasms that are rarely encountered in the genitourinary tract outside the uterus. Pathological confirmation is always needed for definitive diagnosis, in order to rule out malignancies such as leiomyosarcoma. In cases of small leiomyomata, a surveillance strategy can be suggested, although the preferred approach is complete resection. Prognosis seems to be excellent, but available data are based on few, inconsistent series, as is often the case with rare neoplasms. This article presents long-term follow-up data from the most heterogeneous series, in terms of anatomical location, currently available. MATERIAL AND METHODS: The present series of 33 genitourinary leiomyomata was retrieved after joining the "rare urogenital neoplasm" registry of two Italian regions. Two pathologists jointly reviewed all pathological slides and confirmed the diagnosis of leiomyoma. RESULTS: Sixteen cases were localized to the scrotum, eight to the bladder, five to the kidney, two to the prostate, one to the urethra and one to the penis. Mean patient age was 58.4 (range 32-80) years. Mean follow-up was 15.5 (range 2-20) years. CONCLUSIONS: In this highly heterogeneous series, the disease showed excellent long-term recurrence- and progression-free interval. The accuracy of pathological diagnosis, along with the indolent long-term course, make the role of active surveillance amenable for asymptomatic cases, particularly where surgery may result in overtreatment.


Asunto(s)
Leiomiomatosis/diagnóstico , Estadificación de Neoplasias/métodos , Sistema de Registros , Neoplasias Urogenitales/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Diagnóstico Diferencial , Femenino , Humanos , Persona de Mediana Edad , Reproducibilidad de los Resultados
12.
Urologia ; 80(3): 247-50, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24526600

RESUMEN

A case of primary prostate involvement by mantle-cell lymphoma diagnosed at the time of transvesical adenomectomy is reported. Diagnostic difficulties and clinical outcome are also presented. The possibility of prostate involvement by malignant lymphomas, albeit rare, should be considered in any case of histological evidence of dense prostate lymphoid infiltrate in patients with lower urinary tract obstruction, and should be highly suspected in patients with prior history of systemic lymphoma. Immunohistochemical analysis is essential for a correct diagnosis. Both urologists and pathologists should be aware of the existence of such a rare clinical condition.


Asunto(s)
Linfoma de Células del Manto/diagnóstico , Neoplasias de la Próstata/diagnóstico , Enfermedades Raras/diagnóstico , Anciano de 80 o más Años , Humanos , Masculino
13.
Urol Int ; 86(2): 185-90, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21422792

RESUMEN

OBJECTIVE: Neuroendocrine bladder tumours are rare entities known for their aggressive behaviour. The aim of this study was to retrospectively evaluate the outcome of a contemporary series of 14 consecutive bladder neuroendocrine neoplasms observed at 2 institutional hospitals. MATERIALS AND METHODS: The charts of patients with a pathological diagnosis of neuroendocrine bladder tumours observed at 2 institutions in the last 5 years were reviewed. Fourteen cases were retrieved. The main endpoint was to evaluate the pathological features and the cancer-specific survival (CSS) of the cohort. Subanalysis of survival based on the type of treatment received was attempted. RESULTS: Mean age was 70.2 years. The rate of metastatic disease at diagnosis was 57.1%. Mean follow-up was 13.7 months (95% CI 5.1-22.3). The 6-month CSS rate was 57.1%, while the 2-year CSS rate was 21.4%. CSS and overall survival rates overlapped. The median survival for the cohort was 7 months. There was no statistically significant difference in survival between patients who underwent surgery and those who did not. CONCLUSION: Neuroendocrine bladder tumours remain a disease with an extremely unfavourable prognosis. The impact of radical surgery on survival remains questionable. Patients harbouring this rare bladder cancer should be referred for trials assessing neoadjuvant and adjuvant systemic treatment strategies.


Asunto(s)
Tumores Neuroendocrinos/diagnóstico , Neoplasias de la Vejiga Urinaria/diagnóstico , Anciano , Quimioterapia Adyuvante/métodos , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Humanos , Masculino , Oncología Médica/métodos , Persona de Mediana Edad , Metástasis de la Neoplasia , Pronóstico , Estudios Retrospectivos , Resultado del Tratamiento
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...