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Background: The endothelial function has been proven to be an important factor in the pathogenesis of atherosclerosis, hypertension and heart failure. The flow-mediated vasodilation (FMD) of the peripheral artery is an endothelium-dependent function. Brachial-artery ultrasound scanning is the popular method for evaluating FMD. However, good technical training on ultrasonography is required for the user to obtain high-quality data. Therefore, the goal of this study was to propose a new method which only used a sphygmomanometer cuff to occlude the blood flow and record the vascular volume waveform (Vwave).Results: We used this method to assess the FMD in the menstrual cycle for 26 volunteer females. All female subjects were evaluated two times (M: menstrual phase; F: luteal phase) in one menstrual cycle and for two cycles. In the first cycle, the FMD volume ratio in M was 101.9 ± 45.5 % and was higher in L, at 137.5 ± 62.1 % (p = 0.0032 versus M). In the second cycle, the FMD volume ratios in M and L were 91.4 ± 37.0 % and 124.0 ± 56.4 %, respectively (p < 0.001 vs. M).Conclusions: Our results have confirmed those results in the study of Hametner et al. Blood pressure measurement and FMD assessment all used the same mechanic of digital blood pressure monitor, which makes our method suitable using at home. [ABSTRACT FROM AUTHOR]

Background: Systematic aerobe training has positive effects on the compliance of dedicated arterial walls. The adaptations of the arterial structure and function are associated with the blood flow-induced changes of the wall shear stress which induced vascular remodelling via nitric oxide delivered from the endothelial cell. In order to assess functional changes of the common carotid artery over time in these processes, a precise measurement technique is necessary. Before this study, a reliable, precise, and quick method to perform this work is not present.Methods: We propose a fully automated algorithm to analyze the cross-sectional area of the carotid artery in MR image sequences. It contains two phases: (1) position detection of the carotid artery, (2) accurate boundary identification of the carotid artery. In the first phase, we use intensity, area size and shape as features to discriminate the carotid artery from other tissues and vessels. In the second phase, the directional gradient, Hough transform, and circle model guided dynamic programming are used to identify the boundary accurately.Results: We test the system stability using contrast degraded images (contrast resolutions range from 50% to 90%). The unsigned error ranges from 2.86% ± 2.24% to 3.03% ± 2.40%. The test of noise degraded images (SNRs range from 16 to 20 dB) shows the unsigned error ranging from 2.63% ± 2.06% to 3.12% ± 2.11%. The test of raw images has an unsigned error 2.56% ± 2.10% compared to the manual tracings.Conclusions: We have proposed an automated system which is able to detect carotid artery cross sectional boundary in MRI sequences during heart cycles. The accuracy reaches 2.56% ± 2.10% compared to the manual tracings. The system is stable, reliable and results are reproducible. [ABSTRACT FROM AUTHOR]

Background/aim: The dysregulation of matrix metalloproteinase (MMP) proteins has been reported to be involved in the etiology of pterygium. However, studies about the role of matrix metalloproteinase-11 (MMP-11) are lacking. This study is the first to examine the genomic role of MMP-11 in pterygium., Materials and Methods: The genotypes of MMP-11 rs738791, rs2267029, rs738792, and rs28382575 were determined in 140 pterygium cases and 280 non-pterygium controls by utilizing polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and direct sequencing., Results: The genotypic frequencies of MMP-11 rs738792 TT, CT and CC were 40.0%, 50.7%, and 9.3% in the pterygium group, significantly different from those in the non-pterygium group (55.0%, 37.1%, and 7.9%, respectively; p for trend=0.0139). Specifically, individuals carrying the variants CT and CC had a 1.88- and 1.63-fold odds ratio of pterygium risk [95% confidence interval (CI)=1.22-2.89 and 0.77-3.44, p=0.0054 and 0.2834, respectively]. In the dominant model, individuals carrying CT+CC had significantly higher pterygium risk (odds ratio=1.83, 95%CI=1.21-2.77, p=0.0052). No association was found for other MMP-11 polymorphisms. Allelic analysis showed that MMP-11 rs738792 C allele was significantly associated with pterygium risk (odds ratio=1.48, 95%CI=1.08-2.01, p=0.0169). for the variant alleles of other MMP-11 polymorphisms were not associated with pterygium risk., Conclusion: The MMP-11 rs738792 genotypes can serve as a predictive marker for pterygium risk in Taiwanese. Additionally, elucidating the role of MMP-11 in the pathogenesis of pterygium could inform targeted therapies based on MMP-11 modulation., (Copyright © 2024 International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)

Background: A dentist always checks a patient by using panoramic radiography (PR) initially. The measurement of the minimal distance (MD) between the alveolar crest and the mandibular canal (MC) superior border is critically important before the dental implant surgery, extraction of 3rd molar teeth or any surgery in the posterior area of minimal distance (MD). However, the image of MC is not always clear to identify., Objective: A software is needed for training dentists as well as a tool of demonstration to patients in clinics precisely and quickly. Moreover, it should be able to calculate the MD between the alveolar crest and the MC superior border before dental implant., Methods: A computer-aided software system to semi-automatically detect the MC and mental foramen (MF) in the PR with minimal human interference is proposed., Results: The result shows that the averaged relative error (RE) is 1.83% with a standard deviation of 2.31%., Conclusion: The results show that the proposed algorithm is able to detect the MC superior and inferior borders. This system has the potential to train young clinicians and to replace the manual work in measuring the MD between the alveolar crest and the MC superior border with a minimal human intervention.

Surface electromyography (sEMG) is an important measurement for monitoring exercise and fitness. A wireless Bluetooth transmission sEMG measurement system with a sampling frequency of 2 KHz is developed. Traditional muscle fatigue is detected from the median frequency of the sEMG power spectrum. The regression slope of the linear regression of median frequency is an important muscle fatigue index. As fatigue increases, the power spectrum of the sEMG shifts toward lower frequencies. The goal of this study is to evaluate the sensitivity of empirical mode decomposition (EMD) quantifying the electrical manifestations of the local muscle fatigue during exercising in health people. We also compared this method with the raw data and discrete wavelet transform (DWT). Five male and five female volunteers participated. Each subject was asked to run on a multifunctional pedaled elliptical trainer for about 30 minutes, twice a week, and there were a total of six recording times for each subject with a wireless EMG recording system. The results show that sensitivity of the highest frequency component of EMD is better than the highest frequency component of DWT, and raw data.

The oscillometric method has been widely used to measure arterial systolic and diastolic blood pressures, but its potential for arterial blood flow measurements still remains to be explored. The aim of this study was to non-invasively determine arterial blood flow using an oscillometric blood flow measurement system. The system consists of a pneumatic elastic cuff, an air-pumping motor, a releaser valve, a pressure transducer, and an airflow meter. To build a non-linear cuff model, we measured airflow pumped into the pneumatic cuff and cuff pressure using an airflow meter and pressure transducer during the inflation period, respectively. During the deflation period, only the pressure transducer was used to record cuff pressure. Based on the cuff model, the oscillometric blood flow waveform was obtained by integrating the oscillometric pressure waveform. We compared arterial blood flow derived from the maximum amplitude of the oscillometric blood flow waveform with Doppler-measured blood flow calculated with the diameters and blood velocities of the brachial arteries in 32 subjects who underwent diagnostic evaluations for peripheral arterial embolism. A linear correlation coefficient of r = 0.716 was found between the oscillometry- and Doppler-based blood flow measurements in the 32 subjects. These results suggest that blood flow passing through the brachial artery can be quantified non-invasively using the oscillometric approach after appropriate calibration.

We propose a novel dual dynamic programming (DDP) technique for detecting intimal and adventitial layers of the common carotid artery of the B-mode sonographic images. This method embeds the anatomic knowledge into its structure so that the robustness against the speckles is increased. Moreover, it inherits the property of getting the optimal solution as the traditional dynamic programming (TDP). Our experimental study shows that the DDP technique achieves a detection performance comparable to manual tracing achieved by physicians. The results demonstrate that it has the potential to perform qualitatively better than applying TDP twice in intimal and adventitial layer detection on sonographic B-mode images.