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1.
Healthcare (Basel) ; 12(12)2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38921335

RESUMEN

We evaluated the long-term risks of overall cancer and all-cause mortality associated with five types of phytopharmaceuticals and the most commonly used estrogen-progestogen medications for the treatment of postmenopausal syndrome in women. Using data from Taiwan's National Health Insurance Research Database (NHIRD) from 1 January 2000 to 31 December 2018, we conducted a 1:2 matched cohort study with 12,087 eligible patients. We compared phytopharmaceuticals -only users (n = 4029, phytopharmaceuticals group) with HRT-only users (n = 8058, HRT group) with a washout period of ≥6 months. The phytopharmaceuticals group had significantly lower risks of overall cancer and all-cause mortality than the HRT group (adjusted hazard ratio [95% confidence interval]: 0.60 [0.40-0.9] and 0.40 [0.16-0.99], respectively) after over 180 days of use. Bupleurum and Peony Formula were associated with lower risks of overall cancer and all-cause mortality (aHR: 0.57 [0.36-0.92] and 0.33 [0.11-1.05], respectively). In conclusion, phytopharmaceuticals may serve as an alternative therapy to HRT for alleviating menopausal symptoms and reducing health risks, leading to more favorable long-term health outcomes. Further randomized control trials are necessary to validate the findings of this study.

2.
Nano Lett ; 24(25): 7706-7715, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38869369

RESUMEN

Field-free switching (FFS) and spin-orbit torque (SOT)-based neuromorphic characteristics were realized in a W/Pt/Co/NiO/Pt heterostructure with a perpendicular exchange bias (HEB) for brain-inspired neuromorphic computing (NC). Experimental results using NiO-based SOT devices guided the development of fully spin-based artificial synapses and sigmoidal neurons for implementation in a three-layer artificial neural network. This system achieved impressive accuracies of 91-96% when applied to the Modified National Institute of Standards and Technology (MNIST) image data set and 78.85-81.25% when applied to Fashion MNIST images, due presumably to the emergence of robust NiO antiferromagnetic (AFM) ordering. The emergence of AFM ordering favored the FFS with an enhanced HEB, which suppressed the memristivity and reduced the recognition accuracy. This indicates a trade-off between the requirements for solid-state memory and those required for brain-inspired NC devices. Nonetheless, our findings revealed opportunities by which the two technologies could be aligned via controllable exchange coupling.

3.
Sci Rep ; 14(1): 14788, 2024 06 26.
Artículo en Inglés | MEDLINE | ID: mdl-38926484

RESUMEN

This study aims to assess the association between nicotine replacement therapy (NRT), varenicline, and untreated smoking with the risk of developing eye disorders. We employed a new-user design to investigate the association between NRT use and the incidence of eye disorders by the Taiwan National Health Insurance program. This study included 8416 smokers who received NRT and 8416 smokers who did not receive NRT (control group) matched using propensity scores between 2007 and 2018. After adjustment for relevant factors, a multivariable Cox regression analysis revealed that compared with untreated smokers, NRT use was associated with a significantly reduced risk of macular degeneration (hazard ratio [HR]: 0.34; 95% confidence interval [CI]: 0.13-0.87, P = 0.024). When stratified by dose, short-term NRT use (8-28 defined daily doses) was associated with significantly lower risk of glaucoma (HR: 0.35; 95% CI: 0.16-0.80, P = 0.012) and a trend toward reduced risk of cataract (HR: 0.60; 95% CI: 0.36-1.01, P = 0.053) compared to no treatment. However, these associations were not observed with long-term NRT use. The results of this real-world observational study indicate that NRT use, particularly short-term use, was associated with a lower risk of certain eye disorders compared to no treatment for smoking cessation. Long-term NRT use did not demonstrate the same benefits. Thus, short-term NRT may be a beneficial treatment strategy for reducing the risk of eye disorders in smokers attempting to quit. However, further evidence is required to verify these findings and determine the optimal duration of NRT use.


Asunto(s)
Catarata , Glaucoma , Degeneración Macular , Cese del Hábito de Fumar , Humanos , Masculino , Femenino , Glaucoma/epidemiología , Glaucoma/etiología , Persona de Mediana Edad , Degeneración Macular/epidemiología , Degeneración Macular/etiología , Estudios Retrospectivos , Catarata/epidemiología , Taiwán/epidemiología , Anciano , Adulto , Fumar/efectos adversos , Fumar/epidemiología , Dispositivos para Dejar de Fumar Tabaco , Incidencia , Vareniclina/uso terapéutico
4.
Angew Chem Int Ed Engl ; : e202407702, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38751355

RESUMEN

The current bottleneck in the development of efficient photocatalysts for hydrogen evolution is the limited availability of high-performance acceptor units. Over the past nine years, dibenzo[b,d]thiophene sulfone (DBS) has been the preferred choice for the acceptor unit. Despite extensive exploration of alternative structures as potential replacements for DBS, a superior substitute remains elusive. In this study, a symmetry-breaking strategy was employed on DBS to develop a novel acceptor unit, BBTT-1SO. The asymmetric structure of BBTT-1SO proved beneficial for increasing multiple moment and polarizability. BBTT-1SO-containing polymers showed higher efficiencies for hydrogen evolution than their DBS-containing counterparts by up to 166 %. PBBTT-1SO exhibited an excellent hydrogen evolution rate (HER) of 222.03 mmol g-1 h-1 and an apparent quantum yield of 27.5 % at 500 nm. Transient spectroscopic studies indicated that the BBTT-1SO-based polymers facilitated electron polaron formation, which explains their superior HERs. PBBTT-1SO also showed 14 % higher HER in natural seawater splitting than that in deionized water splitting. Molecular dynamics simulations highlighted the enhanced water-PBBTT-1SO polymer interactions in salt-containing solutions. This study presents a pioneering example of a substitute acceptor unit for DBS in the construction of high-performance photocatalysts for hydrogen evolution.

5.
Sci Rep ; 13(1): 23082, 2023 12 27.
Artículo en Inglés | MEDLINE | ID: mdl-38155257

RESUMEN

Hepatitis C virus (HCV) infection may cause chronic liver disease, liver cirrhosis, and liver cancer. It has been reported to associate with habits including alcohol, betel nut and cigarette use. We aimed to investigate the association between alcohol, betel nut, and cigarette use with HCV infection in Taiwan and to explore their effects. A total of 121,421 participants were enrolled from the Taiwan Biobank. They were stratified into two groups according to whether they had (n = 2750; 2.3%) or did not have (n = 118,671; 97.7%) HCV infection. All participants were also classified into four groups according to the number of habits, including a history of alcohol drinking, betel nut chewing, and cigarette smoking. There were 85,406 (no habit), 24,299 (one habit), 8659 (two habits), and 3057 (three habits) participants in the four groups, respectively. Multivariable analysis showed that the participants who had an alcohol drinking history (odds ratio [OR] 1.568; 95% confidence interval [CI] 1.388-1.773; p < 0.001), betel nut chewing history (OR 1.664; 95% CI 1.445-1.917; p < 0.001), cigarette smoking history (OR 1.387; 95% CI 1.254-1.535; p < 0.001), were significantly associated with HCV infection. Furthermore, the participants were classified into four groups according to the number of habits as follows: 85,406 (no habit), 24,299 (one habit), 8659 (two habits), and 3057 (three habits). The HCV infection rates in these four groups were 2.11%, 2.14%, 3.23%, and 4.78%, respectively. Compared to the participants with no or one habit, those with two habits had a higher HCV infection rate (all p < 0.001). In addition, compared to the participants who had no, one or two habits, those who had three habits also had higher HCV infection rates (all p < 0.001). The participants who had three habits had the highest prevalence of HCV infection. In an era when most HCV can be cured, understanding the epidemiology link between habits and HCV may help the case finding.


Asunto(s)
Hepatitis C , Neoplasias Hepáticas , Productos de Tabaco , Humanos , Hepacivirus , Areca/efectos adversos , Taiwán/epidemiología , Consumo de Bebidas Alcohólicas/efectos adversos , Consumo de Bebidas Alcohólicas/epidemiología , Hepatitis C/epidemiología
6.
Commun Biol ; 6(1): 1017, 2023 10 07.
Artículo en Inglés | MEDLINE | ID: mdl-37805576

RESUMEN

Heart valve disease is a major cause of mortality and morbidity worldwide with no effective medical therapy and no ideal valve substitute emulating the extremely sophisticated functions of a living heart valve. These functions influence survival and quality of life. This has stimulated extensive attempts at tissue engineering "living" heart valves. These attempts utilised combinations of allogeneic/ autologous cells and biological scaffolds with practical, regulatory, and ethical issues. In situ regeneration depends on scaffolds that attract, house and instruct cells and promote connective tissue formation. We describe a surgical, tissue-engineered, anatomically precise, novel off-the-shelf, acellular, synthetic scaffold inducing a rapid process of morphogenesis involving relevant cell types, extracellular matrix, regulatory elements including nerves and humoral components. This process relies on specific material characteristics, design and "morphodynamism".


Asunto(s)
Prótesis Valvulares Cardíacas , Ingeniería de Tejidos , Calidad de Vida , Válvulas Cardíacas , Andamios del Tejido
7.
Physiol Rev ; 2023 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-37732828

RESUMEN

While studying the aortic valve in isolation has facilitated the development of life-saving procedures and technologies, the dynamic interplay of the aortic valve and its surrounding structures is vital to preserving their function across the wide range of conditions encountered in an active lifestyle. Our view is that these structures should be viewed as an integrated functional unit, herein referred to as the aortic valve apparatus (AVA). The coupling of the aortic valve and root, left ventricular outflow tract, and blood circulation is crucial for AVA's functions: unidirectional flow out of the left ventricle, coronary perfusion, reservoir function, and supporting left ventricular function. In this review, we explore the multiscale biological and physical phenomena that underly the simultaneous fulfilment of these functions. A brief overview of the tools used to investigate the AVA is included, such as: medical imaging modalities, experimental methods, and computational modelling, specifically fluid-structure interaction (FSI) simulations, is included. Some pathologies affecting the AVA are explored, and insights are provided on treatments and interventions that aim to maintain quality of life. The concepts explained in this paper support the idea of AVA being an integrated functional unit and help identify unanswered research questions. Incorporating phenomena through the molecular, micro, meso and whole tissue scales is crucial for understanding the sophisticated normal functions and diseases of the AVA.

8.
Quant Imaging Med Surg ; 13(8): 5153-5167, 2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37581029

RESUMEN

Background: Lower extremity venous disease (LEVD) is a complex disorder, and determining the etiology of LEVD is paramount for treatment selection. Two-dimensional phase-contrast magnetic resonance imaging (2D PC-MRI) can provide an objective measure of hemodynamic status and may help differentiate between different etiologies of LEVD. A total of 271 participants, including 256 symptomatic patients with venous lower extremity disease and 15 healthy volunteers, were collected in this cohort study. Methods: It is a single-center prospective observational study using 2D PC-MRI analysis to assess the hemodynamic characteristics of patients with LEVD among participants recruited between April 2017 and October 2021 at a tertiary hospital. The approval institutional review board number for this study were 201802137B0, 201901058B0, 202100938B0, and 202102344B0. Participants were classified as venous reflux (VR) and venous obstruction (VO) by standard ultrasonography. 2D PC-MRI by 1.5 T scanner revealed stroke volume (SV), forward flow volume (FFV), absolute stroke volume (ASV), mean flux (MF), velocity time integral (VTI), and mean velocity (MV) for each selected venous segments. Results: 2D PC-MRI assessed 167 diseased legs from the 116 VR patients [mean age ± standard deviation (SD): 57.9±12.8 years; 39 males] and 113 diseased legs from the 95 VO patients (mean age ± SD: 66.4±12.8 years; 42 males). 2D PC-MRI analysis demonstrated discrimination ability to differentiate from VR to VO [SV, FFV, ASV, MF, VTI, and MV in the various venous segments, respectively, P≤0.001; area under the curve (AUC) =62-68.8%, P≤0.001 by Mann-Whitney U test]. The ratio data (morbid limb to normal limb) in the same individual with single-leg disease revealed differences between VR and VO (SV, FFV, ASV, and MF in the various venous segments, respectively; P<0.05; AUC =60.2-68.7%, P≤0.05 by Mann-Whitney U test). The most favorable differentiating variables of ratios were FFV in the great saphenous veins [AUC =68.7%, 95% confidence interval (CI): 59.8-77.6%] and ASV in the external iliac veins (AUC =67.4%, 95% CI: 58.7-76.2%). Conclusions: Quantitative 2D PC-MRI analysis is capable of differentiating VR from VO. It also provides an important diagnostic capability for preoperative evaluation.

9.
Medicina (Kaunas) ; 59(7)2023 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-37512105

RESUMEN

Background and Objectives: This study was conducted to investigate whether Pseudomonas aeruginosa (PA) infections of arteriovenous grafts (AVGs) recur more frequently than other bacterial infections following treatment with revision. Materials and Methods: Operative procedures, including total excision, subtotal excision, and revision, were performed on 60 patients to treat 65 AVG infections. Final outcomes were classified as no infection recurrence, infection recurrence, and death without prior recurrence. In the competing risk setting, the cumulative incidence was estimated using the cumulative incidence function and Gray's test, and the associations between outcomes and different variables were estimated using a subdistribution hazard (SDH) model. Results: Comparing AVG infections with and without recurrence, PA infection was not associated with a higher risk of infection recurrence (p = 0.13); however, the first operative procedure type was associated with infection recurrence (p = 0.04). AVGs with PA infection were associated with a higher total number of surgical interventions (p < 0.05) than AVGs without PA infection. Regarding the cumulative incidences of outcomes, for AVGs treated with subtotal excision or revision, the cumulative incidence of recurrent infection was 3.3-fold higher for those with PA infection than without one year after the first surgery. However, when AVGs were treated with revision alone, the cumulative incidence was 4.1-fold. After excluding AVGs treated with total excision, the SDH model was applied, obtaining a hazard ratio for infection recurrence of 16.05 (p = 0.02) for AVGs with PA infection compared with AVGs without PA infection. No other variables were significantly associated with infection recurrence. Conclusions: For subtotal resection and revision, AVGs infected with PA had a higher recurrence rate than those infected with other species. However, revision surgery may aggravate the recurrence rate.


Asunto(s)
Derivación Arteriovenosa Quirúrgica , Implantación de Prótesis Vascular , Infecciones por Pseudomonas , Humanos , Implantación de Prótesis Vascular/efectos adversos , Grado de Desobstrucción Vascular , Derivación Arteriovenosa Quirúrgica/efectos adversos , Infecciones por Pseudomonas/epidemiología , Infecciones por Pseudomonas/cirugía , Infecciones por Pseudomonas/etiología , Diálisis Renal , Estudios Retrospectivos , Resultado del Tratamiento , Factores de Riesgo
10.
Eur J Cardiothorac Surg ; 64(4)2023 10 04.
Artículo en Inglés | MEDLINE | ID: mdl-37522885

RESUMEN

OBJECTIVES: The aim of this study was to develop a method to quantify the peel force in an in vitro model simulating repair of ascending aortic dissections with tissue glue (Bioglue). METHODS: This study adapted an adhesive T-Peel test for the determination of the peel strength of adhesives by measuring the peeling force of a T-shaped bonded tissue. Measurements were performed on iatrogenic dissected ascending porcine aorta, which has been repaired with Bioglue using different pressure levels. Four conditions were tested: zero sample pressure according to the manufacturer's recommendation (n = 10), low (504 Pa; n = 11), moderate pressure (1711 Pa; n = 24) and pressure applied by a round shaped vascular 'Borst clamp' (1764 Pa; n = 23). Non-parametric one-way analysis of variance was applied for statistical significance. RESULTS: The median peel force (lower quartile, upper quartile) of aortic samples increased depending on the applied pressure: [no pressure 0.030 N/mm (0.016, 0.057), low pressure 0.040 N/mm (0.032, 0.070) and moderate pressure 0.214 N/mm (0.050, 0.304)]. Samples pressurized with the Borst clamp reached 0.078 N/mm (0.046, 0.152), which was comparable to the peel force of the unpeeled controls [0.107 N/mm (0.087, 0.124)]. Compared to samples without pressure, Bioglue with the application of the Borst clamp (P = 0.021) and with moderate pressure (P = 0.0007) performed significantly better. CONCLUSIONS: The novel T-Peel test offers an attractive method to test tissue glues in defined in vitro environments. Bioglue peel force increased with pressure on the aortic sample in contrast to low or no pressure as per the manufacturer's recommendation. Modifying current recommended use may aid in increasing effectiveness of this approach.


Asunto(s)
Disección de la Aorta Ascendente , Adhesivos Tisulares , Porcinos , Animales , Adhesivos , Adhesivos Tisulares/farmacología , Aorta/cirugía
11.
Small ; 19(42): e2302682, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37322304

RESUMEN

Conjugated polymers (CPs) have recently gained increasing attention as photocatalysts for sunlight-driven hydrogen evolution. However, they suffer from insufficient electron output sites and poor solubility in organic solvents, severely limiting their photocatalytic performance and applicability. Herein, solution-processable all-acceptor (A1 -A2 )-type CPs based on sulfide-oxidized ladder-type heteroarene are synthesized. A1 -A2 -type CPs showed upsurging efficiency improvements by two to three orders of magnitude, compared to their donor-acceptor -type CP counterparts. Furthermore, by seawater splitting, PBDTTTSOS exhibited an apparent quantum yield of 18.9% to 14.8% at 500 to 550 nm. More importantly, PBDTTTSOS achieved an excellent hydrogen evolution rate of 35.7 mmol h-1  g-1 and 150.7 mmol h-1  m-2 in the thin-film state, which is among the highest efficiencies in thin film polymer photocatalysts to date. This work provides a novel strategy for designing polymer photocatalysts with high efficiency and broad applicability.

12.
Antibiotics (Basel) ; 12(6)2023 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-37370389

RESUMEN

Patients receiving hemodialysis are at risk of vascular access infections (VAIs) and are particularly vulnerable to the opportunistic pathogen Staphylococcus aureus. Hemodialysis patients were also at increased risk of infection during the COVID-19 pandemic. Therefore, this study determined the change in the molecular and antibiotic resistance profiles of S. aureus isolates from VAIs during the pandemic compared with before. A total of 102 S. aureus isolates were collected from VAIs between November 2013 and December 2021. Before the pandemic, 69 isolates were collected, 58%, 39.1%, and 2.9% from arteriovenous grafts (AVGs), tunneled cuffed catheters (TCCs), and arteriovenous fistulas (AVFs), respectively. The prevalence of AVG and TCC isolates changed to 39.4% and 60.6%, respectively, of the 33 isolates during the pandemic. Sequence type (ST)59 was the predominant clone in TCC methicillin-resistant S. aureus (MRSA) and AVG-MRSA before the pandemic, whereas the predominant clone was ST8 in AVG-MRSA during the pandemic. ST59 carrying the ermB gene was resistant to clindamycin and erythromycin. By contrast, ST8 carrying the msrA gene was exclusively resistant to erythromycin. The ST distribution for different VAIs changed from before to during the pandemic. The change in antibiotic resistance rate for different VAIs was closely related to the distribution of specific STs.

13.
Nanomedicine ; 50: 102673, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37044193

RESUMEN

Herein, we fabricated gold surface-coated iron titanium core-shell (FeTi@Au) nanoparticles (NPs) with conjugation of angiopep-2 (ANG) (FeTi@Au-ANG) NPs for targeted delivery and improved NPs penetration by receptor-mediated endocytosis to achieve hyperthermic treatment of gliomas. The synthesized "core-shell" FeTi@Au-ANG NPs exhibited spherical in shape with around 16 nm particle size and increased temperature upon alternating magnetic field (AMF) stimulation, rendering them effective for localized hyperthermic therapy of cancer cells. Effective targeted delivery of FeTi@Au-ANG NPs was demonstrated in vitro by improved transport and cellular uptake, and increased apoptosis in glioma cells (C6) compared with normal fibroblast cells (L929). FeTi@Au-ANG NPs exhibited higher deposition in brain tissues and a superior therapeutic effect in an orthotopic intracranial xenograft mouse model. Taken together, our data indicate that FeTi@Au-ANG NPs hold significant promise as a targeted delivery strategy for glioma treatment using hyperthermia.


Asunto(s)
Glioma , Hipertermia Inducida , Nanopartículas , Humanos , Ratones , Animales , Línea Celular Tumoral , Glioma/tratamiento farmacológico , Oro/uso terapéutico
14.
ACS Nano ; 17(7): 6555-6564, 2023 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-36951422

RESUMEN

Defect engineering is of great interest to the two-dimensional (2D) materials community. If nonmagnetic transition-metal dichalcogenides can possess room-temperature ferromagnetism (RTFM) induced by defects, then they will be ideal for application as spintronic materials and also for studying the relation between electronic and magnetic properties of quantum-confined structures. Thus, in this work, we aimed to study gamma-ray irradiation effects on MoS2, which is diamagnetic in nature. We found that gamma-ray exposure up to 9 kGy on few-layered (3.5 nm) MoS2 films induces an ultrahigh saturation magnetization of around 610 emu/cm3 at RT, whereas no significant changes were observed in the structure and magnetism of bulk MoS2 (40 nm) films even after gamma-ray irradiation. The RTFM in a few-layered gamma-ray irradiated sample is most likely due to the bound magnetic polaron created by the spin interaction of Mo 4d ions with trapped electrons present at sulfur vacancies. In addition, density functional theory (DFT) calculations suggest that the defect containing one Mo and two S vacancies is the dominant defect inducing the RTFM in MoS2. These DFT results are consistent with Raman, X-ray photoelectron spectroscopy, and ESR spectroscopy results, and they confirm the breakage of Mo and S bonds and the existence of vacancies after gamma-ray irradiation. Overall, this study suggests that the occurrence of magnetism in gamma-ray irradiated MoS2 few-layered films could be attributed to the synergistic effects of magnetic moments arising from the existence of both Mo and S vacancies as well as lattice distortion of the MoS2 structure.

15.
Sci Rep ; 13(1): 3263, 2023 02 24.
Artículo en Inglés | MEDLINE | ID: mdl-36828951

RESUMEN

Since venous reflux is difficult to quantify, triggered angiography non-contrast-enhanced (TRANCE)-magnetic resonance imaging (MRI) is a novel tool for objectively evaluating venous diseases in the lower extremities without using contrast media. This study included 26 pre-intervention patients with superficial venous reflux in the lower extremities and 15 healthy volunteers. The quantitative flow (QFlow) analyzed the phase shift information from the pixels within the region of interest from MRI. The fast and simple radial basis function neural network (RBFNN) learning model is constructed by determining the parameters of the radial basis function and the weights of the neural network. The input parameters were the variables generated through QFlow, while the output variables were morbid limbs with venous reflux and normal limb classification. The stroke volume, forward flow volume, absolute stroke volume, mean flux, stroke distance, and mean velocity of greater saphenous veins from QFlow analysis could be used to discriminate the morbid limbs of pre-intervention patients and normal limbs of healthy controls. The neural network successfully classified the morbid and normal limbs with an accuracy of 90.24% in the training stage. The classification of venous reflux using the RBFNN model may assist physicians in clinical settings.


Asunto(s)
Pierna , Insuficiencia Venosa , Humanos , Extremidad Inferior , Vena Safena/patología , Imagen por Resonancia Magnética
16.
J Biomech Eng ; 145(7)2023 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-36795016

RESUMEN

A new dissipation function Wv is devised and presented to capture the rate-dependent mechanical behavior of the semilunar heart valves. Following the experimentally-guided framework introduced in our previous work (Anssari-Benam et al., 2022 "Modelling the Rate-Dependency of the Mechanical Behaviour of the Aortic Heart Valve: An Experimentally Guided Theoretical Framework," J. Mech. Behav. Biomed. Mater., 134, p. 105341), we derive our proposed Wv function from the experimental data pertaining to the biaxial deformation of the aortic and pulmonary valve specimens across a 10,000-fold range of deformation rate, exhibiting two distinct rate-dependent features: (i) the stiffening effect in σ-λ curves with increase in rate; and (ii) the asymptotic effect of rate on stress levels at higher rates. The devised Wv function is then used in conjunction with a hyperelastic strain energy function We to model the rate-dependent behavior of the valves, incorporating the rate of deformation as an explicit variable. It is shown that the devised function favorably captures the observed rate-dependent features, and the model provides excellent fits to the experimentally obtained σ-λ curves. The proposed function is thereby recommended for application to the rate-dependent mechanical behavior of heart valves, as well as other soft tissues that exhibit a similar rate-dependent behavior.


Asunto(s)
Válvula Aórtica , Válvula Pulmonar , Estrés Mecánico , Aorta
17.
Arch Med Sci ; 19(1): 86-93, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36817682

RESUMEN

Introduction: The survival outcome of lung cancer patients with end-stage renal disease has been poorly studied in the literature. In this study, we evaluated the effect of end-stage renal disease on lung cancer survival. Material and methods: A retrospective, multicenter, matched-cohort study of lung cancer patients with end-stage renal disease under renal replacement therapy (WITH-ESRD) and without end-stage renal disease (WITHOUT-ESRD) was performed. One WITH-ESRD patient was matched to four WITHOUT-ESRD patients. Results: Baseline clinical characteristics did not differ statistically significantly after matching between the WITH-ESRD and WITHOUT-ESRD groups. WITH-ESRD included 133 patients and WITHOUT-ESRD included 532 patients. Kaplan-Meier survival analysis demonstrated no significant difference in median overall survival between WITH-ESRD patients and WITHOUT-ESRD patients (7.36 months versus 12.25 months, respectively, p = 0.133). Lung cancer WITH-ESRD patients receiving medical treatment had a median overall survival of 5.98 months (95% CI: 4.34-11.76) compared to 14.13 months (95% CI: 11.30-16.43) for WITHOUT-ESRD patients, p = 0.019. Although patients receiving surgical treatment compared to those receiving medical treatment had an improvement of survival by 46% (HR = 0.54, 95% CI: 0.19-1.53, p = 0.243), the difference did not reach statistical significance. Cox regression analysis revealed that male gender and stage IIIA-IV were independent factors associated with poor outcome for WITH-ESRD patients. Conclusions: In our limited experience, the survival for lung cancer with ESRD is not inferior to lung cancer patients without ESRD. The reasons for poor survival for the WITH-ESRD medical treatment group and late diagnosis despite frequent medical visits merit further investigation.

18.
J Vasc Access ; 24(5): 895-903, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34772292

RESUMEN

BACKGROUND: Elevated venous pressure during hemodialysis (VPHD) is associated with arteriovenous graft (AVG) stenosis. This study investigated the role of VPHD variations in the prediction of impending AVG occlusion. METHODS: Data were retrieved from 118 operations to treat AVG occlusion (occlusion group) and 149 operations to treat significant AVG stenosis (stenosis group). In addition to analyzing the VPHD values for the three hemodialysis (HD) sessions prior to the intervention, VPHD values were normalized to mean blood pressure (MBP), blood flow rate (BFR), BFR × MBP, and BFR2 × MBP to yield ratios for analysis. The coefficient of variation (CV) was used to measure relative variations. RESULTS: The within-group comparisons for both groups revealed no significant differences in the VPHD mean and CV values among the three HD sessions prior to intervention. However, the CVs for VPHD/MBP, VPHD/(BFR × MBP), and VPHD/(BFR2 × MBP) exhibited significant elevation in the occlusion group during the last HD session prior to intervention compared with both the penultimate and antepenultimate within-group HD data (p < 0.05). In the receiver operating characteristic curve analysis, the CV for VPHD/(BFR2 × MBP) was the only parameter able to discriminate between the last and the penultimate HD outcomes (p < 0.001). According to a multivariate analysis, after controlling for covariates, CV for VPHD/(BFR2 × MBP) >8.76% was associated with a higher risk of AVG thrombosis (odds ratio: 3.17, p < 0.001). CONCLUSIONS: Increasing the variation in VPHD/(BFR2 × MBP) may increase the probability of AVG occlusion.


Asunto(s)
Derivación Arteriovenosa Quirúrgica , Humanos , Grado de Desobstrucción Vascular , Constricción Patológica , Oclusión de Injerto Vascular , Diálisis Renal , Estudios Retrospectivos , Resultado del Tratamiento
20.
Artículo en Inglés | MEDLINE | ID: mdl-36231768

RESUMEN

N-Nitrosodimethylamine (NDMA), a carcinogenic chemical, has recently been identified in ranitidine. We conducted a population-based study to explore ranitidine use and cancer emergence over time. Using the Taiwan National Health Insurance Research Database, a population-based cohort study was conducted. A total of 55,110 eligible patients who received ranitidine between January 2000 and December 2018 were enrolled in the treated cohort. We conducted a 1:1 propensity-score-matching procedure to match the ranitidine-treated group with the ranitidine-untreated group and famotidine controls for a longitudinal study. The association of ranitidine exposure with cancer outcomes was assessed. A multivariable Cox regression analysis that compared cancer risk with the untreated groups revealed that ranitidine increased the risk of liver (hazard ratio (HR): 1.22, 95% confidence interval (CI): 1.09-1.36, p < 0.001), lung (HR: 1.17, CI: 1.05-1.31, p = 0.005), gastric (HR: 1.26, CI: 1.05-1.52, p = 0.012), and pancreatic cancers (HR 1.35, CI: 1.03-1.77, p = 0.030). Our real-world observational study strongly supports the pathogenic role of NDMA contamination, given that long-term ranitidine use is associated with a higher likelihood of liver cancer development in ranitidine users compared with the control groups of non-ranitidine users treated with famotidine or proton-pump inhibitors.


Asunto(s)
Neoplasias , Ranitidina , Estudios de Cohortes , Dimetilnitrosamina/análisis , Dimetilnitrosamina/toxicidad , Famotidina/uso terapéutico , Humanos , Estudios Longitudinales , Neoplasias/inducido químicamente , Neoplasias/epidemiología , Inhibidores de la Bomba de Protones , Ranitidina/uso terapéutico
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