Background: We have developed velocity-flow urodynamics using Doppler sonography based on the hypothesis that microbubbles formed in the urethra are responsible for Doppler signals. In order to confirm this hypothesis derived from Bernoulli's principle, we investigated the simultaneous detection of cavitation noise and Doppler signals in an experimental system.
Methods: An experimental circuit was built in which a stenosis was created using a glass or silicon tube with tap water used as the sample fluid. Doppler signals, pressure before and after the stenosis, flow rate, flow velocity and cavitation noise were measured. Direct detection of cavitation with a high-speed charged-coupled device (CCD) camera was conducted in the glass tube. The relationship between cross-sectional area and flow velocity in terms of the detection of Doppler signals was analyzed in the silicon tube study.
Results: In the glass tube study, a high-speed CCD camera clearly detected masses of microbubbles associated with cavitation. The range of flow rates creating cavitation completely corresponded with those producing Doppler signals detected by ultrasonography. A similar correlation was observed in the silicon tube study, which showed that a low flow velocity of 41.5 cm/sec through a stenosis with a cross-sectional area of 20 mm(2) created Doppler signals at a flow rate of 8.3 mL/sec.
Conclusion: The results of the present study confirmed that microbubbles created in flowing urine are responsible for Doppler signals. Measurement of velocity-flow urodynamics has great potential to become a non-invasive and reliable alternative to conventional pressure- flow urodynamic studies.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1111/j.1442-2042.2004.00858.x | DOI Listing |
Clin Transl Gastroenterol
January 2025
Department of Ultrasound, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, China.
Background: Gastrointestinal ultrasound (GIUS) is recommended for monitoring Crohn's disease (CD). GIUS scores are used to quantify CD activity. Among them, IBUS-SAS (International Bowel Ultrasound Segmental Activity Score), BUSS (Bowel Ultrasound Score), Simple-US (Simple Ultrasound Score), and SUS-CD (Simple Ultrasound Score for Crohn's Disease) are most commonly used.
View Article and Find Full Text PDFSensors (Basel)
December 2024
Key Laboratory of Science and Technology on Micro-System, Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences, Shanghai 200050, China.
Frequency-modulated continuous-wave (FMCW) radar is used to extract range and velocity information from the beat signal. However, the traditional joint range-velocity estimation algorithms often experience significant performances degradation under low signal-to-noise ratio (SNR) conditions. To address this issue, this paper proposes a novel approach utilizing the complementary ensemble empirical mode decomposition (CEEMD) combined with singular value decomposition (SVD) to reconstruct the beat signal prior to applying the FFT-Root-MUSIC algorithm for joint range and velocity estimation.
View Article and Find Full Text PDFAims: ultrasound (US) diagnosis of enthesitis is burdened of low specificity, especially when it is performed in patients with psoriasis (PsO) but without clinical psoriatic arthritis (PsA), because of mechanical, dysmetabolic and age-related concurrent enthesopatic changes. We propose a novel US score to quantify the cortical-entheseal bone remodeling burden of several peripheral entheses, aiming to improve the specificity of US for PsA-related enthesitis, and to evaluate its diagnostic value in PsO patients with subsequent diagnosis of psoriatic arthritis (PsO/PsA).
Methods: clinical and US data of 119 consecutive patients with moderate/severe PsO and nonspecific musculoskeletal symptoms, were included in this retrospective study.
Sci Rep
January 2025
The 705 Research Institute, China State Shipbuilding Corporation Limited, Xi'an, 710077, China.
To mitigate the impact of the suboptimal ambiguity function of digital television terrestrial multimedia broadcasting (DTMB) signal, used as the illuminator of opportunity in passive bistatic radar, this paper provides a detailed analysis of the ambiguity function characteristics based on the physical structure of the DTMB signal frame. It elucidates the mechanisms behind intra-frame and inter-frame range sidelobes, as well as Doppler sidelobes. Building on this analysis, a novel joint method for suppressing range-Doppler ambiguity sidelobes is proposed to achieve unambiguous target detection.
View Article and Find Full Text PDFCirc Res
January 2025
Experimental Research Center, Beijing Institute of Heart, Lung and Blood Vessel Diseases, Beijing Anzhen Hospital, Capital Medical University, China (H.J.).
Background: Metabolic syndrome heightens cardiovascular disease risk primarily through increased arterial stiffness. We previously demonstrated the involvement of YAP (Yes-associated protein) in high-fat/high-sucrose diet (HFHSD)-induced arterial stiffness via modulation of PPM1B (protein phosphatase Mg/Mn-dependent 1B)-lysine63 (K63) deubiquitination. In this study, we aimed to elucidate the role and mechanisms underlying PPM1B deubiquitination in HFHSD-induced arterial stiffness.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!