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1.
JAMIA Open ; 7(3): ooae088, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39297152

RESUMEN

Objective: This study aimed to optimize Fall Risk Appraisal (FRA) graphing for use in intervention programs tailored toward reducing the fall risk of older adults by using computing graphic functions in the R language. Materials and Methods: We utilized RStudio, a free development environment for the R language, as well as the functions within the "ggplot2" and "grid" packages, to develop a code that would recreate the FRA matrix for use in data visualization and analysis, as well as feedback for older adults. Results: The developed code successfully recreates the FRA matrix in R and allows researchers and clinicians to graph participant data onto the matrix itself. Discussion: The use of an R code allows for a streamlined approach to manipulating the FRA matrix for use in data visualization and feedback for older adults, which improves upon the traditional paper-pencil method that has been previously used. Conclusions: The code presented in this study recreates the FRA matrix instrument in the R language and gives researchers the ability to instantaneously add, remove, or change different aspects of the instrument to improve its readability for researchers and older adults.

2.
Proc Natl Acad Sci U S A ; 121(40): e2319177121, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39298472

RESUMEN

In 2015, the largest recorded harmful algal bloom (HAB) occurred in the Northeast Pacific, causing nearly 100 million dollars in damages to fisheries and killing many protected marine mammals. Dominated by the toxic diatom Pseudo-nitzschia australis, this bloom produced high levels of the neurotoxin domoic acid (DA). Through molecular and transcriptional characterization of 52 near-weekly phytoplankton net-tow samples collected at a bloom hotspot in Monterey Bay, California, we identified active transcription of known DA biosynthesis (dab) genes from the three identified toxigenic species, including P. australis as the primary origin of toxicity. Elevated expression of silicon transporters (sit1) during the bloom supports the previously hypothesized role of dissolved silica (Si) exhaustion in contributing to bloom physiology and toxicity. We find that coexpression of the dabA and sit1 genes serves as a robust predictor of DA one week in advance, potentially enabling the forecasting of DA-producing HABs. We additionally present evidence that low levels of iron could have colimited the diatom population along with low Si. Iron limitation represents an overlooked driver of both toxin production and ecological success of the low-iron-adapted Pseudo-nitzschia genus during the 2015 bloom, and increasing pervasiveness of iron limitation may fuel the escalating magnitude and frequency of toxic Pseudo-nitzschia blooms globally. Our results advance understanding of bloom physiology underlying toxin production, bloom prediction, and the impact of global change on toxic blooms.


Asunto(s)
Diatomeas , Floraciones de Algas Nocivas , Ácido Kaínico , Fitoplancton , Ácido Kaínico/análogos & derivados , Ácido Kaínico/metabolismo , Diatomeas/genética , Diatomeas/metabolismo , Diatomeas/crecimiento & desarrollo , Fitoplancton/genética , Fitoplancton/metabolismo , California , Toxinas Marinas/biosíntesis , Toxinas Marinas/genética , Toxinas Marinas/metabolismo , Neurotoxinas/genética , Neurotoxinas/toxicidad , Neurotoxinas/metabolismo , Hierro/metabolismo
4.
R Soc Open Sci ; 11(6): 231736, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-39100171

RESUMEN

This study aims to investigate the relationship between soft tissue energy dissipation and leg stiffness during running. Eight recreational healthy male runners (age: 22.2 ± 1.0 years; height: 1.84 ± 0.03 m; mass: 73.7 ± 5.7 kg) were asked to run at different speeds and step frequencies. Their soft tissue energy dissipation was estimated by the difference between the total mechanical work of the body, measured as the work done to move the body centre of mass relative to the surroundings plus the work to move the limbs relative to the body centre of mass, and lower-limb joint work. A mass-spring model with an actuator was used to analyse the force-length curve of the bouncing mechanism of running. In this way, the stiffness and damping coefficient were assessed at each speed and step frequency. Pearson's correlations were used to describe the relationship between the deviation from the spring-mass model and soft tissue energy fluctuations. The soft tissue dissipation was found to be significantly influenced by step frequency, with both positive and negative work phases decreasing when step frequency increases. Moreover, deviation from a spring-mass model was positively associated with the amount of soft tissue dissipation (r > 0.6). The findings emphasize the substantial role of soft tissues in dissipating or returning energy during running, behaving in a damped-elastic manner. Also, we introduce a novel approach for evaluating the elastic rebound of the body during running. The insights gained may have broad implications for assessing running mechanics, with potential applications in various contexts.

5.
Toxics ; 12(8)2024 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-39195699

RESUMEN

Polychlorinated dibenzo-p-dioxins and polychlorinated dibenzo-p-furans (PCDD/Fs) are a group of organic chemicals containing three-ring structures that can be substituted with one to eight chlorine atoms, leading to 75 dioxin and 135 furan congeners. As endocrine-disrupting chemicals (EDCs), they can alter physiological processes causing a number of disorders. In this study, quantitative structure-toxicity relationship (QSTR) studies were used to determine the correlations between the PCDD/Fs' molecular structures and various toxicity endpoints. Strong QSTR models, with the coefficients of determination (r2) values greater than 0.95 and ANOVA p-values less than 0.0001 were established between molecular descriptors and the endpoints of bioconcentration, fathead minnow LC50, and Daphnia magna LC50. The ability of PCDD/Fs to bind to several nuclear receptors was investigated via molecular docking studies. The results show comparable, and in some instances better, binding affinities of PCDD/Fs toward the receptors relative to their natural agonistic and antagonistic ligands, signifying possible interference with the receptors' natural biological activities. These studies were accompanied by the molecular dynamics simulations of the top-binding PCDD/Fs to show changes in the receptor-ligand complexes during binding and provide insights into these compounds' ability to interfere with transcription and thereby modify gene expression. This introspection of PCDD/Fs at the molecular level provides a deeper understanding of these compounds' toxicity and opens avenues for future studies.

6.
J Phys Chem A ; 128(35): 7346-7352, 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-39178215

RESUMEN

In this work, we propose a new methodology for obtaining three-dimensional (3D) carbon allotrope structures from 2D ones through topological mapping. The idea is to select a 3D target structure and "slice" it along different structural directions, creating a series of 2D structures. As a proof of concept, we chose the tubulane structure 12-hexa(3,3) as a target. Tubulanes are 3D carbon allotropes based on cross-linked carbon nanotubes. One of the obtained 2D "sliced" structures was mapped into the biphenylene carbon (BPC). We showed that compressing BPC in-plane, biaxially, followed by compression along the z direction using different strain rates could generate not only the target tubulane 12-hexa(3,3) structure but also at least two others: bcc-C6 and an unreported member of the tubulane family, which we called tubulane X. The methodology proposed here is entirely general; it can be used coupled with any quantum method. Considering that the 2D biphenylene carbon network, which is closely related to BPC, has been recently synthesized, the approach proposed here opens new perspectives to obtain new 3D carbon allotropes from 2D structures.

7.
Interface Focus ; 14(4): 20230079, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39129855

RESUMEN

In this article, we examine the scientific and sustainable research capacity outcomes of the 'Congo River: user Hydraulics and Morphology' or CRuHM project, a six-year effort supported by the Royal Society's Africa Capacity Building Initiative. This project brought together a consortium of African and UK universities to undertake the first large-scale scientific expeditions to the Congo basin of the modern era in order to better understand the hydraulics and geomorphology of this understudied but globally important river. The river is essential for navigation, irrigation, drinking water and hydroelectric power generation for the 10 basin countries and is critically important for biodiversity and global nutrient, carbon and climatological cycles. This article summarizes the new scientific understanding contributed by the project and the steps taken to ensure a meaningful legacy that would continue long beyond the finite lifetime of available funding. Actions taken to achieve this include establishing a new hydrology research centre at the University of Kinshasa as well as steps to build a wider international community of Congo basin researchers. In this way, we hope to build momentum for future funding initiatives and collaboration.

9.
Nanoscale ; 16(35): 16430-16438, 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39171412

RESUMEN

Recently, a new 2D carbon allotrope called Irida-Graphene (Irida-G) was proposed, and its reliable stability has been previously predicted. Irida-G is a flat sheet topologically arranged into 3-6-8 carbon rings exhibiting metallic and non-magnetic properties. In this study, we investigated the thermal transport properties of Irida-G using classical reactive molecular dynamics simulations. The findings indicate that Irida-G has an intrinsic thermal conductivity of approximately 215 W mK-1 at room temperature, significantly lower than that of pristine graphene. This decrease is due to characteristic phonon scattering within Irida-G's porous structure. Additionally, the phonon group velocities and vibrational density of states for Irida-G were analyzed, revealing reduced average phonon group velocities compared to graphene. The thermal conductivity of Irida-G is isotropic and shows significant size effects, transitioning from ballistic to diffusive heat transport regimes as the system length increases. These results suggest that while Irida-G has lower thermal conductivity than graphene, it still holds potential for specific thermal management applications, sharing characteristics with other two-dimensional materials.

10.
Neurology ; 103(5): e209753, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39167736

RESUMEN

BACKGROUND AND OBJECTIVES: Updates in Alzheimer disease (AD) diagnostic guidelines by the National Institute on Aging-Alzheimer's Association (NIA-AA) and the International Working Group (IWG) over the past 11 years may affect clinical diagnoses. We assessed how these guidelines affect clinical AD diagnosis in a cohort of cognitively unimpaired (CU) and cognitively impaired (CI) individuals. METHODS: We applied clinical and biomarker data in algorithms to classify individuals from the Alzheimer's Disease Neuroimaging Initiative (ADNI) cohort according to the following diagnostic guidelines for AD: 2011 NIA-AA, 2016 IWG-2, 2018 NIA-AA, and 2021 IWG-3, assigning the following generic diagnostic labels: (1) not AD (nAD), (2) increased risk of developing AD (irAD), and (3) AD. Diagnostic labels were compared according to their frequency, convergence across guidelines, biomarker profiles, and prognostic value. We also evaluated the diagnostic discordance among the criteria. RESULTS: A total of 1,195 individuals (mean age 73.2 ± 7.2 years, mean education 16.1 ± 2.7, 44.0% female) presented different repartitions of diagnostic labels according to the 2011 NIA-AA (nAD = 37.8%, irAD = 23.0%, AD = 39.2%), 2016 IWG-2 (nAD = 37.7%, irAD = 28.7%, AD = 33.6%), 2018 NIA-AA (nAD = 40.7%, irAD = 9.3%, AD = 50.0%), and 2021 IWG-3 (nAD = 51.2%, irAD = 8.4%, AD = 48.3%) frameworks. Discordant diagnoses across all guidelines were found in 512 participants (42.8%) (138 [91.4%] occurring in only ß-amyloid [CU 65.4%, CI 34.6%] and 191 [78.6%] in only tau-positive [CU 71.7%, CI 28.3%] individuals). Differences in predicting cognitive impairment between nAD and irAD groups were observed with the 2011 NIA-AA (hazard ratio [HR] 2.21, 95% CI 1.34-3.65, p = 0.002), 2016 IWG-2 (HR 2.81, 95% CI 1.59-4.96, p < 0.000), and 2021 IWG-3 (HR 3.61, 95% CI 2.09-6.23, p < 0.000), but not with 2018 NIA-AA (HR 1.69, 95% CI 0.87-3.28, p = 0.115). DISCUSSION: Over 42% of the studied population presented discordant diagnoses when using the different examined AD criteria, mostly in individuals with a single positive biomarker. Except for 2018 NIA-AA, all guidelines identified asymptomatic individuals at risk of cognitive impairment. Our findings highlight important differences between the guidelines, emphasizing the necessity for updated criteria with enhanced staging metrics, considering clinical, research, therapeutic, and trial design aspects.


Asunto(s)
Enfermedad de Alzheimer , Humanos , Enfermedad de Alzheimer/diagnóstico , Anciano , Femenino , Masculino , Anciano de 80 o más Años , Disfunción Cognitiva/diagnóstico , Biomarcadores , Guías de Práctica Clínica como Asunto/normas , Neuroimagen , Estudios de Cohortes , Investigación Biomédica/normas , Investigación Biomédica/métodos
11.
J Appl Physiol (1985) ; 137(3): 616-628, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39024409

RESUMEN

In laboratory settings, human locomotion encounters minimal opposition from air resistance. However, moving in nature often requires overcoming airflow. Here, the drag force exerted on the body by different headwind or tailwind speeds (between 0 and 15 m·s-1) was measured during walking at 1.5 m·s-1 and running at 4 m·s-1. To our knowledge, the biomechanical effect of drag in human locomotion has only been evaluated by simulations. Data were collected on eight male subjects using an instrumented treadmill placed in a wind tunnel. From the ground reaction forces, the drag and external work done to overcome wind resistance and to sustain the motion of the center of mass of the body were measured. Drag increased with wind speed: a 15 m·s-1 headwind exerted a drag of ∼60 N in walking and ∼50 N in running. The same tailwind exerted -55 N of drag in both gaits. At this wind speed, the work done to overcome the airflow represented ∼80% of the external work in walking and ∼50% in running. Furthermore, in the presence of fast wind speeds, subjects altered their drag area (CdA) by adapting their posture to limit the increase in air friction. Moving in the wind modified the ratio between positive and negative external work performed. The modifications observed when moving with a head- or tailwind have been compared with moving uphill or downhill. The present findings may have implications for optimizing aerodynamic performance in competitive running, whether in sprints or marathons.NEW & NOTEWORTHY This is the first study to assess the biomechanical adaptations to a wide range of wind speeds inside a wind tunnel. Humans increase their mechanical work and alter their drag area (CdA) by adapting their posture when walking and running against increasing head and tailwinds. The observed drag force applied to the subject is different between walking and running at similar headwind speeds.


Asunto(s)
Carrera , Caminata , Viento , Humanos , Masculino , Fenómenos Biomecánicos/fisiología , Adulto , Caminata/fisiología , Carrera/fisiología , Adulto Joven , Marcha/fisiología , Locomoción/fisiología , Postura/fisiología
12.
J Gerontol Nurs ; 50(7): 12-18, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38959511

RESUMEN

PURPOSE: Physical disabilities may exacerbate the natural decline in sleep quality that occurs with aging. In the current study, we assessed sleep quality and medicinal sleep aid use among 87 community-dwelling older adults with (n = 24) and without (n = 63) physical disabilities. METHOD: Sleep quality, duration, and efficiency were assessed subjectively with the Pittsburgh Sleep Quality Index. Sleep duration and efficiency were objectively measured with actigraphy. Participants self-reported medicinal sleep aid use. RESULTS: Significant group differences were observed in sleep duration measured objectively (p = 0.01) and subjectively (p = 0.04). No other group differences were observed for sleep factors (p > 0.05) or medicinal sleep aid use (p = 0.41). CONCLUSION: Findings show that physical disability may be a factor in sleep duration; however, physical disability was not found to be associated with worsened sleep perception or greater reliance on medicinal sleep aids. Future research should consider longer objective actigraphy assessment windows and explore potential subgroup differences in sex and race/ethnicity. [Journal of Gerontological Nursing, 50(7), 12-18.].


Asunto(s)
Personas con Discapacidad , Vida Independiente , Calidad del Sueño , Humanos , Anciano , Masculino , Femenino , Anciano de 80 o más Años , Pobreza , Actigrafía , Sueño/fisiología , Persona de Mediana Edad
13.
Acta Med Philipp ; 58(2): 27-35, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38966156

RESUMEN

Objective: The coronavirus disease 2019 (COVID-19) pandemic has limited healthcare delivery for patients with chronic diseases, including Systemic Lupus Erythematosus (SLE). This study aims to describe the outcomes of patients with SLE in a national COVID-19 referral center in the Philippines. Methods: A review of records of all adult patients with SLE seen in the University of the Philippines-Philippine General Hospital (UP-PGH) from March 2020 to December 2021 was done. Data about patient characteristics, health encounters, and outcomes before and after the first visit during the study period were extracted. Descriptive statistics were employed. Results: Our population of 403 patients was predominantly young (mean age 34.53 ± 11.14 years), female, and unemployed. This consisted of 370 known cases of SLE, 92 were diagnosed in institutions outside UP-PGH, and 33 new patients. Over the 22-month study period, there were 2,093 medical encounters, most of which were teleconsultations (81.70%). During an average gap of 53.6 ± 26.7 weeks between the last consultation and the first visit within the pandemic study period, 84 patients (22.70%) discontinued at least one of their SLE control medications, 68 (18.38%) patients developed a lupus flare, and 79 (21.35%) were hospitalized for various reasons. On their return to the rheumatology clinic during the pandemic, 37.47% were in lupus flare, 28.29% needed to be hospitalized, and 20 died. However, 86.75% of flares were controlled. During subsequent health encounters, 48 patients had a new flare (43 of these were controlled) and 20 died. The most common reason for hospitalization (n=160) was lupus disease flare and the most common cause of death (n=40) was pneumonia. Sixty patients acquired COVID-19 infection from which most recovered and four died. Conclusion: Audio teleconsultation was the most common method used by our lupus cohort to interact with their doctors during the pandemic. There was an average of a year-long interruption in medical care for 62.70%. More than a third developed a disease flare and 15% acquired COVID-19 but outcomes were good in more than 85%. Despite the challenges posed by the pandemic, the majority of our lupus cohort who were able to continue their treatment had favorable outcomes.

14.
Lancet Oncol ; 25(8): 1070-1079, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39029483

RESUMEN

BACKGROUND: Refractory upper abdominal pain or lower back pain (retroperitoneal pain syndrome) related to celiac plexus involvement characterises pancreatic and other upper gastrointestinal malignancies and is an unmet need. We hypothesised that ablative radiation delivered to the celiac plexus would decrease pain. METHODS: This multicentre, single-arm, phase 2 study was done at eight hospitals in five countries (Israel, Poland, Canada, the USA, and Portugal). Eligible patients aged 18 years or older with an average pain level of 5-10 on the Brief Pain Inventory short form (BPI-SF), an Eastern Cooperative Oncology Group performance status score of 0-2, and either pancreatic cancer or other tumours involving the celiac axis, received a single fraction of 25 Gy of external-beam photons to the celiac plexus. The primary endpoint was complete or partial pain response based on a reduction of the BPI-SF average pain score of 2 points or more from baseline to 3 weeks after treatment. All evaluable patients with stable pain scores were included in response assessment. The trial is registered with ClinicalTrials.gov, NCT03323489, and is complete. FINDINGS: Between Jan 3, 2018, and Dec 28, 2021, 125 patients were treated, 90 of whom were evaluable. Patients were followed up until death. Median age was 65·5 years (IQR 58·3-71·8), 50 (56%) were female and 40 (44%) were male, 83 (92%) had pancreatic cancer, and 77 (86%) had metastatic disease. Median baseline BPI-SF average pain score was 6 (IQR 5-7). Of the 90 evaluable patients at 3 weeks, 48 (53%; 95% CI 42-64) had at least a partial pain response. The most common grade 3-4 adverse events, irrespective of attribution, were abdominal pain (35 [28%] of 125) and fatigue (23 [18%]). 11 serious adverse events of grade 3 or worse were recorded. Two grade 3 serious adverse events were probably attributed to treatment by the local investigators (abdominal pain [n=1] and nausea [n=1]), and nine were possibly attributed to treatment (seven were grade 3: blood bilirubin increased [n=1], duodenal haemorrhage [n=2], abdominal pain [n=2], and progressive disease [n=2]; and two were grade 5: gastrointestinal bleed from suspected varices 24 days after treatment [n=1] and progressive disease [advanced pancreatic cancer] 89 days after treatment [n=1]). INTERPRETATION: Celiac plexus radiosurgery could potentially be a non-invasive palliative option for patients with retroperitoneal pain syndrome. Further investigation by means of a randomised comparison with conventional celiac block or neurolysis is warranted. FUNDING: Gateway for Cancer Research and the Israel Cancer Association.


Asunto(s)
Dolor en Cáncer , Plexo Celíaco , Manejo del Dolor , Radiocirugia , Humanos , Masculino , Femenino , Anciano , Persona de Mediana Edad , Radiocirugia/efectos adversos , Manejo del Dolor/métodos , Dolor en Cáncer/etiología , Neoplasias Pancreáticas/complicaciones , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/cirugía , Dimensión del Dolor , Anciano de 80 o más Años , Resultado del Tratamiento , Adulto , Dolor Abdominal/etiología
15.
Int J Colorectal Dis ; 39(1): 119, 2024 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-39073495

RESUMEN

INTRODUCTION: Despite advances in medical therapy, approximately 33% of Crohn's disease (CD) patients will need surgery within 5 years after initial diagnosis. Several surgical approaches to CD have been proposed including small bowel resection, strictureplasty, and combined surgery with resection plus strictureplasty. Here, we utilize the American College of Surgeons (ACS) national surgical quality registry (NSQIP) to perform a comprehensive analysis of 30-day outcomes between these three surgical approaches for CD. METHODS: The authors queried the ACS-NSQIP database between 2015 and 2020 for all patients undergoing open or laparoscopic resection of small bowel or strictureplasty for CD using CPT and IC-CM 10. Outcomes of interest included length of stay, discharge disposition, wound complications, 30-day related readmission, and reoperation. RESULTS: A total of 2578 patients were identified; 87% of patients underwent small bowel resection, 5% resection with strictureplasty, and 8% strictureplasty alone. Resection plus strictureplasty (combined surgery) was associated with the longest operative time (p = 0.002). Patients undergoing small bowel resection had the longest length of hospital stay (p = 0.030) and the highest incidence of superficial/deep wound infection (44%, p = 0.003) as well as the highest incidence of sepsis (3.5%, p = 0.03). Small bowel resection was found to be associated with higher odds of wound complication compared to combined surgery (OR 2.09, p = 0.024) and strictureplasty (1.9, p = 0.005). CONCLUSION: Our study shows that various surgical approaches for CD are associated with comparable outcomes in 30-day related reoperation and readmission, or disposition following surgery between all three surgical approaches. However, small bowel resection displayed higher odds of developing post-operative wound complications.


Asunto(s)
Enfermedad de Crohn , Intestino Delgado , Humanos , Enfermedad de Crohn/cirugía , Intestino Delgado/cirugía , Intestino Delgado/patología , Estudios Retrospectivos , Resultado del Tratamiento , Masculino , Femenino , Adulto , Tiempo de Internación , Complicaciones Posoperatorias/etiología , Readmisión del Paciente , Reoperación , Persona de Mediana Edad , Procedimientos Quirúrgicos del Sistema Digestivo/efectos adversos , Procedimientos Quirúrgicos del Sistema Digestivo/métodos , Sistema de Registros
16.
J Cardiopulm Rehabil Prev ; 44(5): 369-376, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38885063

RESUMEN

PURPOSE: The World Health Organization has recommended breaking up sitting time to improve cardiovascular health. However, whether isometric exercise can be effectively used as a strategy to break up sitting time remains unclear. Thus, the aim of this study was to analyze the acute effects of breaking up prolonged sitting with isometric wall squat exercise (IWSE) on vascular function and blood pressure (BP) in sedentary adults. METHODS: This randomized crossover trial included 17 adults (53% male, 26 ± 6 yr, 22.4 ± 3.6 kg/m 2 ) with high sedentary behavior (≥ 6 hr/d). The participants completed 2 experimental sessions in a randomized order, both sharing a common sitting period of 180 min: Breaks (2-min breaks were incorporated into the IWSE, with participants maintaining their knees at the angle determined by the incremental test, which occurred every 30 min) and Control (sitting for 180 min continuously). Popliteal artery flow-mediated dilation (FMD) and brachial BP were measured before and at 10 and 30 min after the experimental sessions. RESULTS: The results did not indicate significant session vs time interaction effects on popliteal FMD and brachial BP ( P > .05). A subanalysis including only participants with popliteal FMD reduction after the Control session (n = 11) revealed that Breaks enhanced popliteal FMD after 10 min (1.38 ± 6.45% vs -4.87 ± 2.95%, P = .002) and 30 min (-0.43 ± 2.48% vs -2.11 ± 5.22%, P = .047). CONCLUSION: Breaking up prolonged sitting with IWSE mitigates impaired vascular function resulting from prolonged sitting but has no effect on BP in sedentary adults.


Asunto(s)
Presión Sanguínea , Estudios Cruzados , Ejercicio Físico , Conducta Sedentaria , Sedestación , Humanos , Masculino , Adulto , Femenino , Presión Sanguínea/fisiología , Ejercicio Físico/fisiología , Arteria Poplítea/fisiología , Adulto Joven , Arteria Braquial/fisiología , Factores de Tiempo
17.
ChemMedChem ; : e202400273, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38940296

RESUMEN

Sirtuin 6 (Sirt6), an NAD+-dependent deacylase, has emerged as a promising target for aging-related diseases and cancer. Advancing the medicinal chemistry of Sirt6 modulators is crucial for the development of chemical probes aimed at unraveling the intricate biological functions of Sirt6 and unlocking its therapeutic potential. A proprietary DNA-encoded library yielded Sirt6 inhibitor 2-Pr, displaying remarkable inhibitory activity and isoform-selectivity, and featuring a chemical structure distinct from reported Sirt6 modulators. In this study, we explore the inhibitory mechanism of 2-Pr, evaluating the impact of chemical modifications and presenting a crystal structure of the Sirt6/ADP-ribose/2-Pr complex. Notably, co-crystal structure analysis reveals an unexpected and unprecedented binding mode of Sirt6, with 2-Pr spanning the acyl channel of the enzyme, extending into the acetyl-lysine binding pocket, and reaching toward the C-site. This unique binding mode guides potential avenues for developing potent and selective Sirt6 inhibitors.

18.
Small ; : e2400351, 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38874126

RESUMEN

Schwarzites are porous (spongy-like) carbon allotropes with negative Gaussian curvatures. They are proposed by Mackay and Terrones inspired by the works of the German mathematician Hermann Schwarz on Triply-Periodic Minimal Surfaces (TPMS). This review presents and discusses the history of schwarzites and their place among curved carbon nanomaterials. The main works on schwarzites are summarized and are available in the literature. Their unique structural, electronic, thermal, and mechanical properties are discussed. Although the synthesis of carbon-based schwarzites remains elusive, recent advances in the synthesis of zeolite-templates nanomaterials have brought them closer to reality. Atomic-based models of schwarzites are translated into macroscale ones that are 3D-printed. These 3D-printed models are exploited in many real-world applications, including water remediation and biomedical ones.

19.
Sci Total Environ ; 946: 174250, 2024 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-38936722

RESUMEN

Harmful cyanobacteria blooms are a growing threat in estuarine waters as upstream blooms are exported into coastal environments. Cyanobacteria can produce potent toxins, one of which-hepatotoxic microcystins (MCs)-can persist and accumulate within the food web. Filter-feeding invertebrates may biomagnify toxins up to 100× ambient concentrations. As such, bivalves can be used as an environmentally relevant and highly sensitive sentinel for MC monitoring. To date there has been little research on cyanotoxin bioaccumulation in estuaries. The Sacramento-San Joaquin Delta (Delta) aquatic food web has undergone a profound change in response to widespread colonization of aquatic invasive species such as Asian clams (Corbicula fluminea) in the freshwater portion of the Delta. These clams are prolific-blanketing areas of the Delta at densities up to 1000 clams/m2 and are directly implicated in the pelagic organism decline of threatened and endangered fishes. We hypothesized that Asian clams accumulate MCs which may act as an additional stressor to the food web and MCs would seasonally be in exceedance of public health advisory levels. MCs accumulation in Delta Asian clams and signal crayfish (Pacifastacus leniusculus) were studied over a two-year period. ELISA and LC-MS analytical methods were used to measure free and protein-bound MCs in clam and crayfish tissues. We describe an improved MC extraction method for use when analyzing these taxa by LC-MS. MCs were found to accumulate in Asian clams across all months and at all study sites, with seasonal maxima occurring during the summer. Although MC concentrations rarely exceeded public health advisory levels, the persistence of MCs year-round still poses a chronic risk to consumers. Crayfish at times also accumulated high concentrations of MCs. Our results highlight the utility of shellfish as sentinel organisms for monitoring in estuarine areas.


Asunto(s)
Monitoreo del Ambiente , Cadena Alimentaria , Microcistinas , Microcistinas/análisis , Animales , California , Estuarios , Astacoidea , Contaminantes Químicos del Agua/análisis , Bivalvos/metabolismo , Corbicula
20.
Artículo en Inglés | MEDLINE | ID: mdl-38928969

RESUMEN

Marital relationships offer health benefits, including a lower risk of cardiovascular disease (CVD). However, quality of the relationship matters; ambivalent behaviors may increase CVD risk by affecting blunted nocturnal blood pressure (BP) dipping. This study tracked daytime and nocturnal SBP and DBP in 180 normotensive individuals (90 couples; participant mean age 25.04; 91.58% white) over a 24 h period using ambulatory blood pressure monitors to explore the impact of martial quality. Results showed that perceptions of spousal ambivalence were associated with blunted nocturnal BP dipping. Perceptions of one's own behavior as ambivalent also showed blunted nocturnal dipping. When in an ambivalent relationship, a gender interaction was found such that women were most likely to have blunted SBP dipping, but men were more likely to have blunted nocturnal DBP dipping. Overall, this study found an association between ambivalence and BP dipping, thus uncovering one virtually unexplored pathway by which marital relationships may have adverse effects on health.


Asunto(s)
Presión Sanguínea , Matrimonio , Humanos , Masculino , Femenino , Adulto , Presión Sanguínea/fisiología , Matrimonio/psicología , Adulto Joven , Monitoreo Ambulatorio de la Presión Arterial , Sueño/fisiología , Ritmo Circadiano/fisiología , Esposos/psicología
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