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2.
Artículo en Inglés | MEDLINE | ID: mdl-39136871

RESUMEN

Atherosclerotic cardiovascular disease (ASCVD), a leading cause of mortality and morbidity, is associated with a substantial healthcare and economic burden. Reduction of low-density lipoprotein cholesterol (LDL-C) to guideline-recommended goals is crucial in the prevention or management of ASCVD, particularly in those at high risk. Despite the availability of several effective lipid-lowering therapies (LLTs), up to 80% of patients with ASCVD do not reach evidence-based LDL-C goals. This nonattainment may be due to poor adherence to, and lack of timely utilization of, LLTs driven by a range of variables, including polypharmacy, side effects, clinical inertia, costs, and access issues. Inclisiran was approved by the US Food and Drug Administration in 2021 as a novel, twice-yearly, healthcare provider (HCP)-administered LLT. In-office administration allows HCPs more control of drug acquisition, administration, and reimbursement, and may allow for more timely care and increased patient monitoring. In the USA, in-office administered drugs are considered a Medical Benefit and can be acquired and reimbursed using the "buy-and-bill" process. Buy-and-bill is a standard system for medication administration already established in multiple therapeutic areas, including oncology, vaccines, and allergy/immunology. Initiating in-office administration will involve new considerations for clinicians in the cardiovascular specialty, such as the implementation of new infrastructure and processes; however, it could ultimately increase treatment adherence and improve cardiovascular outcomes for patients with ASCVD. This article discusses the potential implications of buy-and-bill for the cardiology specialty and provides a practical guide to implementing HCP-administered specialty drugs in US clinical practice.

3.
Support Care Cancer ; 32(9): 584, 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39134893

RESUMEN

BACKGROUND: The aim of this study was to understand the experiences of young men with a diagnosis of testicular cancer (TC) using a narrative approach, with the intention of informing models of care and support in clinical services. METHODS: TC patients were recruited to participate in one of four focus groups examining their lived experiences from diagnosis. Focus groups were recorded and transcribed and analyzed using a narrative approach. RESULTS: A total of 4 focus groups were held from March to May 2019, involving 21 participants. Participants were currently on treatment (n = 2), < 2 years from treatment completion (n = 7), or > 2 years from treatment completion (n = 12). Two overarching meta-themes were identified: Negotiating Identity (comprising "recovery, repair and control"; "breaking the news"; "threats to fertility and virility"; "multiple masculinities") and Needing to Adjust (comprising "trauma and post-traumatic growth"; "facing vulnerability"; "managing to cope"; "secrecy vs. privacy"). Shared themes relating to environments for support, conversations about cancer, and time stress were also identified. CONCLUSIONS: Despite the significant cure rates for testicular cancer, the psychosocial needs of patients diagnosed with TC are paramount and potentially long-lasting. Improved clinical care for these patients includes exploration of both physical and psychosocial concerns over multiple timepoints. Opportunities for peer support and mentorship may be essential to support these vulnerable patients.


Asunto(s)
Adaptación Psicológica , Grupos Focales , Neoplasias Testiculares , Humanos , Masculino , Neoplasias Testiculares/psicología , Neoplasias Testiculares/terapia , Adulto , Adulto Joven , Narración , Investigación Cualitativa , Apoyo Social
4.
Health Lit Res Pract ; 8(2): e89-e90, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38852074
5.
Curr Oncol ; 31(6): 3122-3148, 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38920721

RESUMEN

Despite ongoing screening efforts, colorectal cancer (CRC) remains a leading cause of death in Canada. The aim of this study was to better understand the experiences of Canadian CRC patients with their family practitioners (FPs) during and after their CRC diagnosis. Patient-reported data were collected through an online questionnaire to understand their CRC diagnosis experiences and identify potential gaps in care. Various factors contributing to challenges throughout a patient's CRC diagnosis (e.g., delayed CRC diagnosis) were determined using descriptive, qualitative, and inferential analyses. These factors could be targeted to optimize CRC care. This study found that 40.6% of the 175 respondents were unaware of at least one of the following aspects of CRC prior to their diagnosis: early-age onset (EAO), symptoms, and screening procedures. While 84.6% had access to a family physician (FP) before their diagnosis, only 17.7% were diagnosed by FPs. Higher proportions of younger individuals experienced misdiagnoses and felt dismissed compared to older individuals. Only half felt fully informed about their diagnosis when it was explained to them by their FP, while 53.1% had their diagnosis explained in plain language. Transitioning towards patient-centred care would promote pre-diagnosis CRC awareness, address differences in management of CRC care (e.g., dismissal and support), and accommodate for age and health-literacy-related disparities, thereby improving CRC care pathways for patients. Future research should investigate FPs experiences in detecting CRC cases to develop educational resources and recommendations, enhancing early detection and improving patient outcomes (1).


Asunto(s)
Neoplasias Colorrectales , Humanos , Canadá , Femenino , Masculino , Persona de Mediana Edad , Anciano , Médicos de Familia , Adulto , Encuestas y Cuestionarios , Detección Precoz del Cáncer , Anciano de 80 o más Años
6.
Curr Oncol ; 31(6): 3149-3160, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38920722

RESUMEN

The incidence of early onset colorectal cancer (EOCRC) in Canada has increased. To address the growing incidence of EOCRC, Colorectal Cancer Canada (CCC) developed the Never Too Young (N2Y) program to identify gaps in care and evaluate patient and caregiver experiences with CRC. The survey was available online using SurveyMonkey across Canada between 12 December 2022 and 1 May 2023. The patient and caregiver survey consisted of 113 and 94 questions, respectively. A total of 108 EOCRC patients and 20 caregivers completed the survey. Many respondents were unaware of EOCRC (41.6%) and the disease symptoms (45.2%) before diagnosis. Patient age at diagnosis was between 45 and 50 years in 31.7%, and 72.8% of them were diagnosed at stage III or IV. A perception of an initial misdiagnosis was common (67.4%) for EOCRC patients, and 51.2% felt dismissed due to their age. Patients and caregivers reported impacts of EOCRC on their mental health, with 70.9% of patients expressing a need for support with depression and 93.3% of caregivers experiencing a constant fear of recurrence of their loved one's cancer. Improving the Canadian population's awareness of EOCRC (e.g., CRC symptoms) is important for ensuring timely diagnoses. Similarly, it is critical to ensure that healthcare providers are aware of the increase in EOCRC cases and the unique needs of these patients. Re-evaluation of the CRC screening age should be undertaken in Canada to determine whether lowering the start age to 45 years will improve outcomes in this demographic.


Asunto(s)
Cuidadores , Neoplasias Colorrectales , Humanos , Neoplasias Colorrectales/psicología , Cuidadores/psicología , Canadá , Persona de Mediana Edad , Masculino , Femenino , Encuestas y Cuestionarios , Adulto , Edad de Inicio
7.
Proc Natl Acad Sci U S A ; 121(25): e2313193121, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38857390

RESUMEN

Renewable Portfolio Standards (RPSs) are one of the most prevalent and impactful clean energy policies implemented by states in the United States. This paper investigates the regional spillover effect of RPS policies using a directed dyad panel dataset of renewable electricity generation in US states from 1991 to 2021. Regional spillover effect is measured in two ways: by considering the influence of an RPS enacted in neighboring states and in states in the same regional transmission organization or independent system operator region. We use dyadic fixed effects estimation and conclude that the neighboring state's RPS stringency score is a strong determinant of a state's total renewable electricity generation. For states without an RPS, the positive influence of an RPS in a neighboring state is larger when the non-RPS state has more abundant renewable energy resources than the neighboring RPS state. Our findings suggest that past RPS policy evaluation research using a confined within-state focus may have underestimated the holistic impact of an RPS, as the impacts of an RPS policy can extend beyond the enacting state's borders. Overall, this study contributes to an improved understanding of the holistic impact of state RPS policies.

8.
Phys Rev E ; 109(5-2): 055305, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38907478

RESUMEN

Literature studies of the lattice Boltzmann method (LBM) demonstrate hydrodynamics beyond the continuum limit. This includes exact analytical solutions to the LBM, for the bulk velocity and shear stress of Couette flow under diffuse reflection at the walls through the solution of equivalent moment equations. We prove that the bulk velocity and shear stress of Couette flow with Maxwell-type boundary conditions at the walls, as specified by two-dimensional isothermal lattice Boltzmann models, are inherently linear in Mach number. Our finding enables a systematic variational approach to be formulated that exhibits superior computational efficiency than the previously reported moment method. Specifically, the number of partial differential equations (PDEs) in the variational method grows linearly with quadrature order while the number of moment method PDEs grows quadratically. The variational method directly yields a system of linear PDEs that provide exact analytical solutions to the LBM bulk velocity field and shear stress for Couette flow with Maxwell-type boundary conditions. It is anticipated that this variational approach will find utility in calculating analytical solutions for novel lattice Boltzmann quadrature schemes and other flows.

10.
Brain Res ; 1839: 149040, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-38815643

RESUMEN

Traumatic brain injury (TBI) is a complex pathophysiological process that results in a variety of neurotransmitter, behavioral, and cognitive deficits. The locus coeruleus-norepinephrine (LC-NE) system is a critical regulator of arousal levels and higher executive processes affected by TBI including attention, working memory, and decision making. LC-NE axon injury and impaired signaling within the prefrontal cortex (PFC) is a potential contributor to the neuropsychiatric symptoms after single, moderate to severe TBI. The majority of TBIs are mild, yet long-term cognitive deficits and increased susceptibility for further injury can accumulate after each repetitive mild TBI. As a potential treatment for restoring cognitive function and daytime sleepiness after injury psychostimulants, including methylphenidate (MPH) that increase levels of NE within the PFC, are being prescribed "off-label". The impact of mild and repetitive mild TBI on the LC-NE system remains limited. Therefore, we determined the extent of LC-NE and arousal dysfunction and response to therapeutic doses of MPH in rats following experimentally induced single and repetitive mild TBI. Microdialysis measures of basal NE efflux from the medial PFC and arousal measures were significantly lower after repetitive mild TBI. Females showed higher baseline PFC-NE efflux than males following single and repetitive mild TBI. In response to MPH challenge, males exhibited a blunted PFC-NE response and persistent arousal levels following repetitive mild TBI. These results provide critical insight into the role of catecholamine system dysfunction associated with cognitive deficits following repeated injury, outcome differences between sex/gender, and lack of success of MPH as an adjunctive therapy to improve cognitive function following injury.


Asunto(s)
Conmoción Encefálica , Estimulantes del Sistema Nervioso Central , Metilfenidato , Norepinefrina , Corteza Prefrontal , Ratas Sprague-Dawley , Animales , Masculino , Norepinefrina/metabolismo , Femenino , Corteza Prefrontal/metabolismo , Corteza Prefrontal/efectos de los fármacos , Estimulantes del Sistema Nervioso Central/farmacología , Metilfenidato/farmacología , Conmoción Encefálica/metabolismo , Conmoción Encefálica/fisiopatología , Conmoción Encefálica/tratamiento farmacológico , Ratas , Lesiones Traumáticas del Encéfalo/metabolismo , Lesiones Traumáticas del Encéfalo/tratamiento farmacológico , Lesiones Traumáticas del Encéfalo/fisiopatología , Locus Coeruleus/efectos de los fármacos , Locus Coeruleus/metabolismo , Nivel de Alerta/efectos de los fármacos , Nivel de Alerta/fisiología , Microdiálisis/métodos
11.
J Phys Chem B ; 128(18): 4315-4324, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38687467

RESUMEN

Excess energy absorbed by photosystems (PSs) can result in photoinduced oxidative damage. Transfer of such energy within the core pigments of the reaction center in the form of triplet excitation is important in regulating and preserving the functionality of PSs. In the bacterial reaction center (BRC), the special pair (P) is understood to act as the electron donor in a photoinduced charge transfer process, triggering the charge separation process through the photoactive branch A pigments that experience a higher polarizing environment. At this work, triplet excitation energy transfer (TEET) in BRC is studied using a computational perspective to gain insights into the roles of the dielectric environment and interpigment orientations. We find in agreement with experimental observations that TEET proceeds through branch B. The TEET process toward branch B pigment is found to be significantly faster than the hypothetical process proceeding through branch A pigments with ps and ms time scales, respectively. Our calculations find that conformational differences play a major role in this branch asymmetry in TEET, where the dielectric environment asymmetry plays only a secondary role in directing the TEET to proceed through branch B. We also address TEET processes asserting the role of carotenoid as the final triplet energy acceptor and in a mutant form, where the branch pigments adjacent to P are replaced by bacteriopheophytins. The necessary electronic excitation energies and electronic state couplings are calculated by the recently developed polarization-consistent framework combining a screened range-separated hybrid functional and a polarizable continuum mode. The polarization-consistent potential energy surfaces are used to parametrize the quantum mechanical approach, implementing Fermi's golden rule expression of the TEET rate calculations.


Asunto(s)
Transferencia de Energía , Proteínas del Complejo del Centro de Reacción Fotosintética , Proteínas del Complejo del Centro de Reacción Fotosintética/química , Proteínas del Complejo del Centro de Reacción Fotosintética/metabolismo , Antioxidantes/química , Antioxidantes/metabolismo , Teoría Funcional de la Densidad
12.
Behav Brain Res ; 467: 115002, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38636779

RESUMEN

Mild traumatic brain injury (mTBI) disrupts cognitive processes that influence risk taking behavior. Little is known regarding the effects of repetitive mild injury (rmTBI) or whether these outcomes are sex specific. Risk/reward decision making is mediated by the prefrontal cortex (PFC), which is densely innervated by catecholaminergic fibers. Aberrant PFC catecholamine activity has been documented following TBI and may underlie TBI-induced risky behavior. The present study characterized the effects of rmTBI on risk/reward decision making behavior and catecholamine transmitter regulatory proteins within the PFC. Rats were exposed to sham, single (smTBI), or three closed-head controlled cortical impact (CH-CCI) injuries and assessed for injury-induced effects on risk/reward decision making using a probabilistic discounting task (PDT). In the first week post-final surgery, mTBI increased risky choice preference. By the fourth week, males exhibited increased latencies to make risky choices following rmTBI, demonstrating a delayed effect on processing speed. When levels of tyrosine hydroxylase (TH) and the norepinephrine reuptake transporter (NET) were measured within subregions of the PFC, females exhibited dramatic increases of TH levels within the orbitofrontal cortex (OFC) following smTBI. However, both males and females demonstrated reduced levels of OFC NET following rmTBI. These results indicate the OFC is susceptible to catecholamine instability after rmTBI and suggests that not all areas of the PFC contribute equally to TBI-induced imbalances. Overall, the CH-CCI model of rmTBI has revealed time-dependent and sex-specific changes in risk/reward decision making and catecholamine regulation following repetitive mild head injuries.


Asunto(s)
Conmoción Encefálica , Catecolaminas , Toma de Decisiones , Corteza Prefrontal , Recompensa , Asunción de Riesgos , Animales , Masculino , Femenino , Toma de Decisiones/fisiología , Catecolaminas/metabolismo , Corteza Prefrontal/metabolismo , Conmoción Encefálica/metabolismo , Conmoción Encefálica/fisiopatología , Tirosina 3-Monooxigenasa/metabolismo , Ratas Sprague-Dawley , Ratas , Modelos Animales de Enfermedad , Proteínas de Transporte de Noradrenalina a través de la Membrana Plasmática/metabolismo
13.
Ther Drug Monit ; 2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38648648

RESUMEN

BACKGROUND: Detecting antidrug antibodies (ADAs) against infliximab or adalimumab is useful for therapeutic drug monitoring. Various ADA detection methods exist, and antibody titer is an output in some algorithms. Homogenous mobility shift assay (HMSA) measures relative ADA concentration and determines drug-ADA complex size in vitro. However, the relevance of complex size determination in drug monitoring remains unclear. Hence, the association between complex size, ADA concentration, and sample detectable neutralizing activity was evaluated. METHODS: Sera from infliximab-treated and adalimumab-treated patients who tested positive for ADA in the National Screening Service were analyzed using 3 ADA assays. HMSA determined the relative ADA concentrations and complex sizes, competitive ligand-binding assay evaluated the sample neutralizing capacity, and enzyme-linked immunosorbent assay detected immunoglobulin (Ig)G4 ADA. RESULTS: Most ADA-positive samples (>80%) formed drug-ADA dimer complexes, whereas 17% had dimer and multimer complexes, and 3% had multimeric complexes. Multimer presence had 100% positive predictive value for detectable neutralizing activity. ADA concentration and detectable neutralizing activity were moderately correlated (r = 0.65) in adalimumab-treated patients and strongly correlated (r = 0.81) in infliximab-treated patients. In adalimumab-treated patients, multimer presence was a stronger predictor of neutralizing activity than ADA concentration was, but not in infliximab-treated patients. However, in infliximab-treated patient samples, multimer presence revealed a distinct subset with high ADA concentrations, neutralizing activity, and IgG4 ADA. CONCLUSIONS: Multimers detected using HMSA had a strong positive predictive value for competitive ligand-binding assay detectable neutralizing activity. Multimeric IgG4-containing ADA-drug complexes revealed a distinct subset of infliximab-treated patient samples, whose clinical relevance merits further investigation.

14.
Cancers (Basel) ; 16(7)2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38610971

RESUMEN

Cancer is the primary underlying condition for most Canadians who are provided Medical Assistance in Dying (MAID). However, it is unknown whether cancer patients who are provided MAID experience disproportionally higher symptom burden compared to those who are not provided MAID. Thus, we used a propensity-score-matched cohort design to evaluate longitudinal symptom trajectories over the last 12 months of patients' lives, comparing cancer patients in Alberta who were and were not provided MAID. We utilized routinely collected retrospective Patient-Reported Outcomes (PROs) data from the Edmonton Symptom Assessment System (ESAS-r) reported by Albertans with cancer who died between July 2017 and January 2019. The data were analyzed using mixed-effect models for repeated measures to compare differences in symptom trajectories between the cohorts over time. Both cohorts experienced increasing severity in all symptoms in the year prior to death (ß from 0.086 to 0.231, p ≤ .001 to .002). Those in the MAID cohort reported significantly greater anxiety (ß = -0.831, p = .044) and greater lack of appetite (ß = -0.934, p = .039) compared to those in the non-MAID cohort. The majority (65.8%) of patients who received MAID submitted their request for MAID within one month of their death. Overall, the MAID patients did not experience disproportionally higher symptom burden. These results emphasize opportunities to address patient suffering for all patients with cancer through routine collection of PROs as well as targeted and early palliative approaches to care.

15.
Curr Oncol ; 31(3): 1460-1469, 2024 03 11.
Artículo en Inglés | MEDLINE | ID: mdl-38534943

RESUMEN

Canada has one of the most complex and rigorous drug approval and public reimbursement processes and is, unfortunately, one of the countries with the longest delays in drug access. To assess the overall impact of systemic delays in access to cancer therapy, a targeted literature review (TLR) was performed to identify studies associated with the clinical, economic, and quality of life impacts of delayed access to oncology drugs. Using MEDLINE/PubMed databases and snowballing, four unique records met the eligibility criteria. Results revealed that clinical outcomes were the most impacted by systemic delays in access to oncology drugs (e.g., life years lost, overall survival, and progression-free survival). The four articles retrieved by the TLR specifically illustrated that a substantial number of life years could potentially be saved by increasing systemic efficiency regarding the development, approval, and reimbursement processes of new drugs for advanced malignancies. It is imperative that initiatives are put in place to improve the performance and speed of Canadian drug regulatory and health technology assessment (HTA) processes, especially for new cancer therapeutics. The proposed solutions in this paper include better coordination between HTA and Canadian payers to harmonize coverage decisions, international collaborations, information sharing, and national standards for timeliness in oncology drug access.


Asunto(s)
Neoplasias , Calidad de Vida , Humanos , Canadá , Neoplasias/tratamiento farmacológico , Aprobación de Drogas , Reembolso de Seguro de Salud
16.
J Am Coll Radiol ; 21(7): 1058-1066, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38286300

RESUMEN

PURPOSE: Challenges from administrative support, scanners' heterogeneity, patient size variation, and protocol mapping hinder CT protocol and dose management. We present a holistic approach to overcome these challenges. METHODS: A dose tracking software was selected with two key requirements: intelligent protocol mapping and customizable dose threshold settings according to the patient size. A multifaceted workflow was carefully implemented. It included patient size-dependent dose thresholds for e-mail alerts, a base protocol archive on a website with a unified format using an in-house developed reformat software upon protocol export, prompt dose alert follow-up, and well-controlled protocol changes. The thresholds were iteratively updated following protocol changes or review of dose statistics. The program outcome was evaluated using 11 protocols from January 2020 to May 2023 (N = 148,678) in comparison to ACR's achievable dose (AD) and dose reference levels (DRLs). RESULTS: The 75th percentile dose data were lower than the ACR's DRL on average, ranging from -4.9% to -36%. The median doses were in a range of -23% to 19% on average in comparison with the ACR's AD. The median value from pulmonary embolism scans initially showed 36% higher than the AD but was gradually reduced to nearly 3% lower than the AD. The percentage of unjustified alerted cases decreased from 80% in first half year of 2020 to 17% in the first 5 months of 2023. CONCLUSIONS: The results showed that our holistic approach to protocol and dose management has been effective. The impact to practice has been prompt and sustainable.


Asunto(s)
Dosis de Radiación , Tomografía Computarizada por Rayos X , Humanos , Tomografía Computarizada por Rayos X/métodos , Programas Informáticos , Protocolos Clínicos , Protección Radiológica/métodos , Flujo de Trabajo
17.
Chest ; 165(6): 1415-1420, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38211701

RESUMEN

BACKGROUND: Endotracheal aspirates (ETAs) are widely used for microbiologic studies of the respiratory tract in intubated patients. However, they involve sampling through an established endotracheal tube using suction catheters, both of which can acquire biofilms that may confound results. RESEARCH QUESTION: Does standard clinical ETA in intubated patients accurately reflect the authentic lower airway bacterial microbiome? STUDY DESIGN AND METHODS: Comprehensive quantitative bacterial profiling using 16S rRNA V1-V2 gene sequencing was applied to compare bacterial populations captured by standard clinical ETA vs contemporaneous gold standard samples acquired directly from the lower airways through a freshly placed sterile tracheostomy tube. The study included 13 patients undergoing percutaneous tracheostomy following prolonged (median, 15 days) intubation. Metrics of bacterial composition, diversity, and relative quantification were applied to samples. RESULTS: Pre-tracheostomy ETAs closely resembled the gold standard immediate post-tracheostomy airway microbiomes in bacterial composition and community features of diversity and quantification. Endotracheal tube and suction catheter biofilms also resembled cognate ETA and fresh tracheostomy communities. INTERPRETATION: Unbiased molecular profiling shows that standard clinical ETA sampling has good concordance with the authentic lower airway microbiome in intubated patients.


Asunto(s)
Intubación Intratraqueal , Microbiota , ARN Ribosómico 16S , Traqueostomía , Humanos , Masculino , Femenino , Traqueostomía/métodos , Traqueostomía/instrumentación , Persona de Mediana Edad , Anciano , Biopelículas , Bacterias/aislamiento & purificación , Bacterias/genética , Succión
18.
Nature ; 626(7997): 66-71, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38233521

RESUMEN

Ever since its discovery1, the notion of the Berry phase has permeated all branches of physics and plays an important part in a variety of quantum phenomena2. However, so far all its realizations have been based on a continuous evolution of the quantum state, following a cyclic path. Here we introduce and demonstrate a conceptually new manifestation of the Berry phase in light-driven crystals, in which the electronic wavefunction accumulates a geometric phase during a discrete evolution between different bands, while preserving the coherence of the process. We experimentally reveal this phase by using a strong laser field to engineer an internal interferometer, induced during less than one cycle of the driving field, which maps the phase onto the emission of higher-order harmonics. Our work provides an opportunity for the study of geometric phases, leading to a variety of observations in light-driven topological phenomena and attosecond solid-state physics.

19.
Artif Organs ; 48(2): 182-190, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37787082

RESUMEN

BACKGROUND: The objective of this study was to assess the pulsatility preservation capability of the universal ventricular assist device (UVAD) when used as a biventricular assist device (BVAD). This evaluation was conducted through an in vitro experiment, utilizing a pulsatile biventricular circulatory mock loop. METHODS: Two UVAD pumps were tested in a dual setup (BVAD) in the circulatory model with the simulated conditions of left heart failure (HF), right HF, and moderate/severe biventricular HF (BHF). The total flow, aortic pulse pressure, the pulse augmentation factor (PAF), the energy-equivalent pressure (EEP), and the surplus hemodynamic energy (SHE) were observed at various pump speeds to evaluate the pulsatility. RESULTS: The aortic pulse pressure increased from the baseline (without pump) in all simulated hemodynamic conditions. The PAF ranged from 17%-35% in healthy, left HF, right HF, and mild BHF conditions, with the highest PAF of 90% being observed in the severe BHF condition. The EEP correlated with LVAD flow in all groups (R2 = 0.87-0.97) and increased from the baseline in all cases. The SHE peaked at approximately 5-6 L/min of LVAD support and was likely to decrease at higher LVAD pump flow. The largest decrease in SHE from the baseline, 53%, was observed in the mild BHF conditions with the highest LVAD and RVAD support. CONCLUSIONS: The UVAD successfully demonstrated the ability to preserve pulsatility in vitro, and to optimize the cardiac output, as an isolated circulatory support device option (RVAD or LVAD) and when used for BVAD support.


Asunto(s)
Insuficiencia Cardíaca , Corazón Auxiliar , Humanos , China , Etnicidad , Hemodinámica , Gasto Cardíaco , Insuficiencia Cardíaca/cirugía
20.
ASAIO J ; 70(2): 116-123, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-37851000

RESUMEN

Cleveland Clinic's continuous-flow total artificial heart (CFTAH) is being developed at our institution and has demonstrated system reliability and optimal performance. Based on the results from recent chronic in vivo experiments, CFTAH has been revised, especially to improve biocompatibility. The purpose of this article is to report our progress in developing CFTAH. To improve biocompatibility, the right impeller, the pump housing, and the motor were reviewed for design revision. Updated design features were based on computational fluid dynamics analysis and observations from in vitro and in vivo studies. A new version of CFTAH was created, manufactured, and tested. All hemodynamic and pump-related parameters were observed and found to be within the intended ranges, and the new CFTAH yielded acceptable biocompatibility. Cleveland Clinic's continuous-flow total artificial heart has demonstrated reliable performance, and has shown satisfactory progress in its development.


Asunto(s)
Corazón Artificial , Corazón Auxiliar , Informe de Investigación , Reproducibilidad de los Resultados , Hemodinámica , Hidrodinámica
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