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1.
PLoS One ; 19(8): e0307073, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39172973

RESUMEN

OBJECTIVES: A dynamic warm-up (DWU) comprising exercise involving rhythmic muscle actions results in an acute increase in range of motion; however, recent findings suggest that a passive one using self-massage techniques might elicit a similar effect. This study's purpose was to compare the acute effect of leg cycling DWU on sit-and-reach score to the effect of a preparatory regimen of foam rolling (FR) or percussive massage (PM). DESIGN: Single-blind, randomized, repeated-measures crossover study. METHODS: Thirty-two asymptomatic, physically-active participants (male; n = 17) aged 20.9 ± 1.5 years performed sit-and-reach tests before, immediately following and 10-, 20- and 30-minutes following eight minutes of each of the "warm-ups." Analyses of variance at each time point across conditions and for the percent change elicited by each intervention were conducted to determine significant differences (p < 0.05). RESULTS: Repeated-measures ANOVA revealed a significant difference between mean percent difference of sit-and-reach score for FR (8.8 ± 0.5%) compared to DWU and PM (p = 0.046 and 0.048, respectively) while DWU (6.3 ± 0.8%) and PM (6.8 ± 0.5%) did not differ (p = 0.717). There were no differences between scores across interventions at any of the four time points. CONCLUSIONS: A bout of FR or PM resulted in an acute increase in a sit-and-reach score during a test performed immediately post and at 10-, 20- and 30-minutes post that was similar in magnitude to that which was present following leg cycling. These passive "warm-ups" are appropriate alternate strategies that can be employed to improve performance on a sit-and-reach test.


Asunto(s)
Estudios Cruzados , Masaje , Ejercicio de Calentamiento , Humanos , Masculino , Adulto Joven , Femenino , Masaje/métodos , Ejercicio de Calentamiento/fisiología , Método Simple Ciego , Adulto , Rango del Movimiento Articular/fisiología
2.
Retina ; 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39173030

RESUMEN

PURPOSE: To compare visual outcomes and recurrence rates between pro re nata (PRN), treat-and-extend and stop (TES), and treat-and-extend with chronic maintenance dosing (TEM) regimens of anti-vascular endothelial growth factor (VEGF) injections for myopic macular neovascularization (MNV) in multiethnic patients. METHODS: This retrospective study included patients treated with PRN, TES, or TEM for myopic MNV using intravitreal bevacizumab or ranibizumab. The primary outcome measure was visual improvement at 12 months. RESULTS: We included 127 eyes of 117 patients (75 females and 42 males). The mean follow-up duration was 37.9 months. We compared the outcomes of PRN (47 eyes [37%]), TES (52 eyes [41%]), and TEM (28 eyes [22%]). All groups showed significant visual improvement at 12 months and at the final follow-up (all P<0.05). Visual outcomes did not differ significantly between the three groups at 12 months and final follow-up (all P>0.05). However, the number of eyes with recurrences was significantly higher in the PRN group and significantly lower in the TEM group during follow-up (38%, 21%, and 11% in the PRN, TES, and TEM groups, respectively; P=0.020). The PRN group received the fewest injections during follow-up (5.3, 10.9, and 19.9 injections in the PRN, TES, and TEM groups respectively; P<0.001). CONCLUSIONS: Anti-VEGF injections with PRN, TES, or TEM regimens are effective for myopic MNV and have comparable visual outcomes. Since PRN provides favorable outcomes with fewer injections, it should be the first-line approach. However, a treat-and-extend approach with TES and TEM may be an option given individual patient factors.

3.
New Phytol ; 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39148398

RESUMEN

Stem respiration constitutes a substantial proportion of autotrophic respiration in forested ecosystems, but its drivers across different spatial scales and land-use gradients remain poorly understood. This study quantifies and examines the impact of logging disturbance on stem CO2 efflux (EA) in Malaysian Borneo. EA was quantified at tree- and stand-level in nine 1-ha plots over a logging gradient from heavily logged to old-growth using the static chamber method. Tree-level results showed higher EA per unit stem area in logged vs old-growth plots (37.0 ± 1.1 vs 26.92 ± 1.14 g C m-2 month-1). However, at stand-level, there was no difference in EA between logged and old-growth plots (6.7 ± 1.1 vs 6.0 ± 0.7 Mg C ha-1 yr-1) due to greater stem surface area in old-growth plots. Allocation to growth respiration and carbon use efficiency was significantly higher in logged plots. Variation in EA at both tree- and stand-level was driven by tree size, growth and differences in investment strategies between the forest types. These results reflect different resource allocation strategies and priorities, with a priority for growth in response to increased light availability in logged plots, while old-growth plots prioritise maintenance and cell structure.

4.
medRxiv ; 2024 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-39148821

RESUMEN

Background: People with HIV (PWH) are at elevated risk for atherosclerotic cardiovascular disease (ASCVD). Underrepresented racial and ethnic groups (UREGs) with HIV in the southern U.S. are disproportionately affected, yet whether cardiology specialist care for this at-risk group improves blood pressure and lipid control or prevents cardiovascular events is unknown. Methods: We evaluated a cohort of PWH from UREGs at elevated ASCVD risk without known cardiovascular disease who received HIV-related care from 2015-2018 at four academic medical centers in the Southern United States with follow up through 2020. Primary outcomes were blood pressure control (<140/90 mmHg) and lipid control (LDL-C ≤ 100 mg/dl) over 2 years and time to first major adverse cardiovascular (MACE) event. Statistical analyses were adjusted for cohort/site and patient factors including HIV measures and comorbidities. Results: Among 3972 included PWH (median age 47 years old, 32.6% female) without diagnosed cardiovascular disease, 276 (6.9%) had a cardiology clinic visit. Cardiology clinic visits were not significantly associated with subsequent blood pressure control (adjusted OR 0.78, 95% CI 0.49-1.24, p=0.29) or lipid control (adjusted OR 2.25, 95% CI 0.72-7.01, p=0.16). Over a median follow up of 5 years, patients who had a cardiology clinic visit had higher risk of MACE, overall mortality, and falsification endpoints (hospitalization or death from accident/trauma and pneumonia/sepsis) indicating a higher risk group overall, even after adjusting for measured risk factors. Conclusions: Among UREG PWH at elevated cardiovascular risk, a cardiology clinic visit was not associated with improved cardiovascular risk factors or reduced risk of cardiovascular events. Our study suggests that seeing a cardiologist is not alone sufficient to promote cardiovascular health or prevent cardiovascular events among PWH, but with low confidence given the higher risk among those who had a cardiology visit. What is known?: People with HIV are at increased cardiovascular risk, and the burden of both cardiovascular disease and HIV are high among people from underrepresented racial and ethnic groups who live in the Southern United States.Treating people with HIV at elevated cardiovascular risk with statins reduces risk of cardiovascular events. What the study adds?: Among people with HIV at elevated cardiovascular risk from underrepresented racial and ethnic groups who received care at four academic medical centers in the southern United States, cardiology clinic visits were not associated with better lipid control, blood pressure control, or prevention of cardiovascular events.People with HIV who attended a cardiology clinic visit had higher risk of cardiovascular events and mortality.

5.
Pulm Circ ; 14(3): e12419, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39175520

RESUMEN

Therapies for inoperable chronic thromboembolic pulmonary hypertension (CTEPH) include balloon pulmonary angioplasty (BPA) and PH-specific medical therapy. This study compares survival and its predictors before and after the introduction of BPA. BPA was independently associated with survival; however, there was no difference in overall survival between the two cohorts.

6.
Nat Electron ; 7(3): 234-243, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-39155947

RESUMEN

Organic electrochemical transistors (OECTs) can be used to create biosensors, wearable devices and neuromorphic systems. However, restrictions in the micro- and nanopatterning of organic semiconductors, as well as topological irregularities, often limit their use in monolithically integrated circuits. Here we show that the micropatterning of organic semiconductors by electron-beam exposure can be used to create high-density (up to around 7.2 million OECTs per cm2) and mechanically flexible vertical OECT arrays and circuits. The energetic electrons convert the semiconductor exposed area to an electronic insulator while retaining ionic conductivity and topological continuity with the redox-active unexposed areas essential for monolithic integration. The resulting p- and n-type vertical OECT active-matrix arrays exhibit transconductances of 0.08-1.7 S, transient times of less than 100 µs and stable switching properties of more than 100,000 cycles. We also fabricate vertically stacked complementary logic circuits, including NOT, NAND and NOR gates.

7.
JACC Adv ; 3(9): 101130, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39157753

RESUMEN

Background: The adult congenital heart disease (ACHD) population is growing and risk prediction is important to predict adverse outcome and consult patients during their lifecourse. Objectives: This study aims to describe the long-term prognostic value of blood biomarkers in ACHD. Methods: In this prospective observational cohort study, 602 patients with moderate or complex ACHD were included (median age 32.5 years [IQR: 24.7-41.2], 42% female, 90% New York Heart Association I). N-terminal pro-brain natriuretic peptide (NT-proBNP), high-sensitive-troponin T, growth differentiation factor 15, high-sensitive-C-reactive protein, suppression of tumorigenicity-2 and galectin-3, as well as full blood count, renal function, LDL, and HDL were measured. Cox models were applied to relate the selected biomarkers with the primary end point of all-cause mortality and secondary end point of mortality or heart failure. Standardized HRs adjusted for relevant prognostic factors, including age, sex, and complexity of diagnosis, were reported. Results: Abnormal biomarker levels were present in 424 (70.4%) patients. During a median follow-up of 10.1 years, 41 (6.8%) patients died and 81 (13.5%) developed heart failure. Associations were observed between the primary and secondary end point and red cell distribution width, NT-proBNP, and growth differentiation factor 15. In a multibiomarker model, only NT-proBNP remained associated with mortality (HR: 2.74; 95% CI: 2.01-3.74). NT-proBNP significantly improved the C-statistic of the clinical prediction model (0.85-0.92). Based on NT-proBNP alone, low-risk patients could be identified. Patients with NT-proBNP <76 ng/L showed a 10-year heart failure-free survival of 98.5%. Conclusions: Blood biomarkers have prognostic value in ACHD. NT-proBNP improves risk prediction and is able to identify low-risk patients. Its routine use should be implemented in ACHD.

9.
bioRxiv ; 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39149370

RESUMEN

Apoferritin (apoF) is commonly used as a test specimen in single-particle electron cryo-microscopy (cryo-EM), since it consistently produces density maps that go to 3 Å resolution or higher. When we imaged apoF with a laser phase plate (LPP), however, we observed more severe particle-to-particle variation in the images than we had previously thought to exist. Similarly, we found that images of ribulose bisphosphate carboxylase/oxygenase (rubisco) also exhibited a much greater amount of heterogeneity than expected. By comparison to simulations of images, we verified that the heterogeneity is not explained by the known features of the LPP, shot noise, or differences in particle orientation. We also demonstrate that our specimens are comparable to those previously used in the literature, based on using the final-reconstruction resolution as the metric for evaluation. All of this leads us to the hypothesis that the heterogeneity is due to damage that has occurred either during purification of the specimen or during preparation of the grids. It is not, however, our goal to explain the causes of heterogeneity; rather, we report that using the LPP has made the apparent damage too obvious to be ignored. In hindsight, similar heterogeneity can be seen in images of apoF and the 20S proteasome which others had recorded with a Volta phase plate. We therefore conclude that the increased contrast of phase-plate images (at low spatial frequencies) should also make it possible to visualize, on a single-particle basis, various forms of biologically functional heterogeneity in structure that had previously gone unnoticed.

10.
JAMA Netw Open ; 7(8): e2429154, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39163042

RESUMEN

Importance: The incidence of opioid-associated out-of-hospital cardiac arrest (OA-OHCA) has grown from less than 1% of OHCA in 2000 to between 7% and 14% of OHCA in recent years; American Heart Association (AHA) protocols suggest that emergency medical service (EMS) clinicians consider naloxone in OA-OHCA. However, it is unknown whether naloxone improves survival in these patients or in patients with undifferentiated OHCA. Objective: To evaluate the association of naloxone with clinical outcomes in patients with undifferentiated OHCA. Design, Setting, and Participants: Retrospective cohort study of EMS-treated patients aged 18 or older who received EMS treatment for nontraumatic OHCA in 3 Northern California counties between 2015 and 2023. Data were analyzed using propensity score-based models from February to April 2024. Exposure: EMS administration of naloxone. Main Outcomes and Measures: The primary outcome was survival to hospital discharge; the secondary outcome was sustained return of spontaneous circulation (ROSC). Covariates included patient and cardiac arrest characteristics (eg, age, sex, nonshockable rhythm, any comorbidity, unwitnessed arrest, and EMS agency) and EMS clinician determination of OHCA cause as presumed drug-related. Results: Among 8195 patients (median [IQR] age, 65 [51-78] years; 5540 male [67.6%]; 1304 Asian, Native Hawaiian, or Pacific Islander [15.9%]; 1119 Black [13.7%]; 2538 White [31.0%]) with OHCA treated by 5 EMS agencies from 2015 to 2023, 715 (8.7%) were believed by treating clinicians to have drug-related OHCA. Naloxone was administered to 1165 patients (14.2%) and was associated with increased ROSC using both nearest neighbor propensity matching (absolute risk difference [ARD], 15.2%; 95% CI, 9.9%-20.6%) and inverse propensity-weighted regression adjustment (ARD, 11.8%; 95% CI, 7.3%-16.4%). Naloxone was also associated with increased survival to hospital discharge using both nearest neighbor propensity matching (ARD, 6.2%; 95% CI, 2.3%-10.0%) and inverse propensity-weighted regression adjustment (ARD, 3.9%; 95% CI, 1.1%-6.7%). The number needed to treat with naloxone was 9 for ROSC and 26 for survival to hospital discharge. In a regression model that assessed effect modification between naloxone and presumed drug-related OHCA, naloxone was associated with improved survival to hospital discharge in both the presumed drug-related OHCA (odds ratio [OR], 2.48; 95% CI, 1.34-4.58) and non-drug-related OHCA groups (OR, 1.35; 95% CI, 1.04-1.77). Conclusions and Relevance: In this retrospective cohort study, naloxone administration as part of EMS management of OHCA was associated with increased rates of ROSC and increased survival to hospital discharge when evaluated using propensity score-based models. Given the lack of clinical practice data on the efficacy of naloxone in OA-OHCA and OHCA in general, these findings support further evaluation of naloxone as part of cardiac arrest care.


Asunto(s)
Servicios Médicos de Urgencia , Naloxona , Antagonistas de Narcóticos , Paro Cardíaco Extrahospitalario , Humanos , Naloxona/uso terapéutico , Paro Cardíaco Extrahospitalario/tratamiento farmacológico , Paro Cardíaco Extrahospitalario/mortalidad , Paro Cardíaco Extrahospitalario/epidemiología , Masculino , Femenino , California/epidemiología , Persona de Mediana Edad , Estudios Retrospectivos , Anciano , Antagonistas de Narcóticos/uso terapéutico , Servicios Médicos de Urgencia/estadística & datos numéricos , Resultado del Tratamiento , Adulto , Reanimación Cardiopulmonar/métodos , Reanimación Cardiopulmonar/estadística & datos numéricos
11.
J Ethnobiol Ethnomed ; 20(1): 78, 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39164694

RESUMEN

BACKGROUND: While bats are tremendously important to global ecosystems, they have been and continue to be threatened by loss of habitat, food, or roosts, pollution, bat diseases, hunting and killing. Some bat species have also been implicated in the transmission of infectious disease agents to humans. While One Health efforts have been ramped up recently to educate and protect human and bat health, such initiatives have been limited by lack of adequate data on the pathways to ensure their support. For instance, data on the role of bats in supporting different components of human welfare assets would be utilized as a stepping stone to champion conservation campaigns. Unfortunately, these data are limited and efforts to synthesize existing literature have majorly focused on few components human welfare leaving other important aspects. METHODS: Here, we analyze benefits associated with bats in the context of welfare economics considering all the asset components. We surveyed scientific and gray literature platforms utilizing particular keywords. We then classified these values using integrated approaches to understand different values across human welfare assets of "health," "material and immaterial assets," "security or safety" and "social or cultural or spiritual relations". RESULTS: We found 235 papers from different countries indicating that bats play fundamental roles in supporting human welfare. These benefits were more prevalent in Asia and Africa. In terms of the use of bats to support welfare assets, bats were majorly utilized to derive material and immaterial benefits (n = 115), e.g., food and income. This was followed by their use in addressing health challenges (n = 99), e.g., treatment of ailments. There was a similarity in the benefits across different regions and countries. CONCLUSION: These results indicate potential opportunities for strengthening bat conservation programs. We recommend more primary studies to enhance understanding of these benefits as well as their effectiveness in deriving the perceived outcomes.


Asunto(s)
Quirópteros , Animales , Humanos , Conservación de los Recursos Naturales , Factores Socioeconómicos
12.
Mil Med ; 189(Supplement_3): 702-709, 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39160885

RESUMEN

INTRODUCTION: Between 2011 and 2014, The Combat Casualty Training Consortium research study sought to evaluate all aspects of combat casualty care, including mortality, with a special focus on the incidence and causes of potentially preventable deaths among U.S. combat fatalities. This study identified a major training gap in critical airway management. To address this gap, the Advanced Joint Airway Management System (AJAMS) was designed and assessed for physical fidelity and educational utility in a population of paramedic instructors. MATERIALS AND METHODS: Paramedic instructors served as participants in this prospective observational pilot study (n = 12). Participants interacted with three airway management trainers: The AJAMS trainer, the Laerdal Airway Management Trainer, and the TruCorp AirSim Advance Bronchi X Trainer. Participants then completed an evaluation of the trainer using a purpose-built data collection instrument that queried the trainer's realism and educational utility. Within-group differences were analyzed via a 1-way repeated measures ANOVA, with a Bonferroni post hoc analysis. Rank data were analyzed via non-parametric Freidman's test, and Wilcoxon signed-rank test post hoc analysis, corrected using the Bonferroni correction. RESULTS: The AJAMS trainer conveys significantly more physical fidelity (visual: P < .001, ηp2 = 0.977; tactile: P < .001, ηp2 = 0.983; and behavioral: P = .001, ηp2 = 0.971) and overall educational utility (χ2(2) = 15.273, P < .001) than the two commercially available skill trainers. CONCLUSIONS: These data suggest that physical fidelity is an important attribute in the design of simulators for health care, as perceived by expert instructors. These data illustrate that the AJAMS-integrated simulator demonstrates unparalleled physical fidelity, relative to commercially available airway management skill trainers.


Asunto(s)
Manejo de la Vía Aérea , Intubación Intratraqueal , Paramédico , Humanos , Manejo de la Vía Aérea/métodos , Manejo de la Vía Aérea/normas , Manejo de la Vía Aérea/instrumentación , Competencia Clínica/normas , Competencia Clínica/estadística & datos numéricos , Auxiliares de Urgencia/educación , Auxiliares de Urgencia/normas , Auxiliares de Urgencia/estadística & datos numéricos , Intubación Intratraqueal/métodos , Intubación Intratraqueal/normas , Intubación Intratraqueal/instrumentación , Paramédico/educación , Paramédico/normas , Paramédico/estadística & datos numéricos , Proyectos Piloto , Estudios Prospectivos
13.
Circ Cardiovasc Imaging ; 17(8): e016852, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39163376

RESUMEN

BACKGROUND: Right ventricular (RV) dysfunction is known to impact prognosis, but its determinants in coronary artery disease are poorly understood. Stress cardiac magnetic resonance (CMR) has been used to assess ischemia and infarction in relation to the left ventricle (LV); the impact of myocardial tissue properties on RV function is unknown. METHODS: Vasodilator stress CMR was performed in patients with known coronary artery disease at 7 sites between May 2005 and October 2018. Myocardial infarction was identified on late gadolinium enhancement-CMR, and infarct transmurality was graded on a per-segment basis. Ischemia was assessed on stress CMR based on first-pass perfusion and localized by using segment partitions corresponding to cine and late gadolinium enhancement analyses. RV function was evaluated by CMR-feature tracking for primary analysis with a global longitudinal strain threshold of 20% used to define impaired RV strain (RVIS); secondary functional analysis via RV ejection fraction was also performed. RESULTS: A total of 2604 patients were studied, among whom RVIS was present in 461 patients (18%). The presence and magnitude of RVIS were strongly associated with LV dysfunction, irrespective of whether measured by LV ejection fraction or wall motion score (P<0.001 for all). Regarding tissue substrate, regions of ischemic and dysfunctional myocardium (ie, hibernating myocardium) and infarct size were each independently associated with RVIS (both P<0.001). During follow-up (median, 4.62 [interquartile range, 2.15-7.67] years), 555 deaths (21%) occurred. Kaplan-Meier analysis for patients stratified by presence and magnitude of RV dysfunction by global longitudinal strain and RV ejection fraction each demonstrated strong prognostic utility for all-cause mortality (P<0.001). RVIS conferred increased mortality risk (hazard ratio, 1.35 [95% CI, 1.11-1.66]; P=0.003) even after controlling for LV function, infarction, and ischemia. CONCLUSIONS: RVIS in patients with known coronary artery disease is associated with potentially reversible LV processes, including LV functional impairment due to ischemic and predominantly viable myocardium, which confers increased mortality risk independent of LV function and tissue substrate.


Asunto(s)
Enfermedad de la Arteria Coronaria , Imagen por Resonancia Cinemagnética , Imagen de Perfusión Miocárdica , Disfunción Ventricular Derecha , Función Ventricular Derecha , Humanos , Masculino , Femenino , Enfermedad de la Arteria Coronaria/fisiopatología , Enfermedad de la Arteria Coronaria/complicaciones , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Persona de Mediana Edad , Anciano , Imagen por Resonancia Cinemagnética/métodos , Disfunción Ventricular Derecha/fisiopatología , Disfunción Ventricular Derecha/etiología , Disfunción Ventricular Derecha/diagnóstico por imagen , Función Ventricular Derecha/fisiología , Imagen de Perfusión Miocárdica/métodos , Valor Predictivo de las Pruebas , Volumen Sistólico/fisiología , Función Ventricular Izquierda/fisiología , Pronóstico , Estados Unidos/epidemiología
14.
Curr Biol ; 34(16): R770-R771, 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39163835

RESUMEN

Insects are posited to be declining globally. This is particularly pertinent in tropical forests, which exhibit both the highest levels of biodiversity and the highest rates of biodiversity loss. However, for the hyper-diverse tropical insects there are scant data available to evidence declines. Understanding tropical insect diversity and its response to environmental change has therefore become a challenge, but it is estimated that 80% of tropical insect species remain undescribed1. Insect biodiversity predictions are based mostly on well-studied taxa and extrapolated to other groups, but no one knows whether resilience to environmental change varies between undescribed and described species. Here, we collected staphylinid beetles from unlogged and logged tropical forests in Borneo and investigated their responses to environmental change. Out of 252 morphospecies collected, 76% were undescribed. Undescribed species showed higher community turnover, reduced abundance and decreased probability of occurrence in logged forests. Thus the unknown components of tropical insect biodiversity are likely more impacted by human-induced environmental change. If these patterns are widespread, how accurate will assessments of insect declines in the tropics be?


Asunto(s)
Biodiversidad , Escarabajos , Clima Tropical , Animales , Escarabajos/fisiología , Borneo , Bosques
15.
J Am Chem Soc ; 146(32): 22295-22305, 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39102651

RESUMEN

Organocatalyzed ring-opening polymerization (ROP) is a versatile technique for synthesizing biodegradable polymers, including polyesters and polycarbonates. We introduce o-phenylene bisurea (OPBU) (di)anions as a novel class of organocatalysts that are fast, easily tunable, mildly basic, and exceptionally selective. These catalysts surpass previous generations, such as thiourea, urea, and TBD, in selectivity (kp/ktr) by 8 to 120 times. OPBU catalysts facilitate the ROP of various monomers, achieving high conversions (>95%) in seconds to minutes, producing polymers with precise molecular weights and very low dispersities (D ≈ 1.01). This performance nearly matches the ideal distribution expected from living polymerization (Poisson distribution). Density functional theory (DFT) calculations reveal that the catalysts stabilize the oxyanion transition state via a hydrogen bond pocket similar to the "oxyanion hole" in enzymatic catalysis. Both experimental and theoretical analyses highlight the critical role of the semirigid o-phenylene linker in creating a hydrogen bond pocket that is tight yet flexible enough to accommodate the oxyanion transition state effectively. These new insights have provided a new class of organic catalysts whose accessibility, moderate basicity, excellent solubility, and unparalleled selectivity and tunability open up new opportunities for controlled polymer synthesis.

16.
Sci Rep ; 14(1): 18384, 2024 08 08.
Artículo en Inglés | MEDLINE | ID: mdl-39117762

RESUMEN

The fundamental question of how forces are generated in a motile cell, a lamellipodium, and a comet tail is the subject of this note. It is now well established that cellular motility results from the polymerization of actin, the most abundant protein in eukaryotic cells, into an interconnected set of filaments. We portray this process in a continuum mechanics framework, claiming that polymerization promotes a mechanical swelling in a narrow zone around the nucleation loci, which ultimately results in cellular or bacterial motility. To this aim, a new paradigm in continuum multi-physics has been designed, departing from the well-known theory of Larché-Cahn chemo-transport-mechanics. In this note, we set up the theory of network growth and compare the outcomes of numerical simulations with experimental evidence.


Asunto(s)
Actinas , Movimiento Celular , Actinas/metabolismo , Modelos Biológicos , Citoesqueleto de Actina/metabolismo , Seudópodos/metabolismo , Seudópodos/fisiología , Fenómenos Biomecánicos , Polimerizacion
17.
Brief Bioinform ; 25(5)2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-39140856

RESUMEN

The field of quantum computing (QC) is expanding, with efforts being made to apply it to areas previously covered by classical algorithms and methods. Bioinformatics is one such domain that is developing in terms of QC. This article offers a broad mapping review of methods and algorithms of QC in bioinformatics, marking the first of its kind. It presents an overview of the domain and aids researchers in identifying further research directions in the early stages of this field of knowledge. The work presented here shows the current state-of-the-art solutions, focuses on general future directions, and highlights the limitations of current methods. The gathered data includes a comprehensive list of identified methods along with descriptions, classifications, and elaborations of their advantages and disadvantages. Results are presented not just in a descriptive table but also in an aggregated and visual format.


Asunto(s)
Algoritmos , Biología Computacional , Teoría Cuántica , Biología Computacional/métodos , Humanos
18.
Nat Commun ; 15(1): 7014, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39147756

RESUMEN

Pliocene global temperatures periodically exceeded modern levels, offering insights into ice sheet sensitivity to warm climates. Ice-proximal geologic records from this period provide crucial but limited glimpses of Antarctic Ice Sheet behavior. We use an ice sheet model driven by climate model snapshots to simulate transient glacial cyclicity from 4.5 to 2.6 Ma, providing spatial and temporal context for geologic records. By evaluating model simulations against a comprehensive synthesis of geologic data, we translate the intermittent geologic record into a continuous reconstruction of Antarctic sea level contributions, revealing a dynamic ice sheet that contributed up to 25 m of glacial-interglacial sea level change. Model grounding line behavior across all major Antarctic catchments exhibits an extended period of receded ice during the mid-Pliocene, coincident with proximal geologic data around Antarctica but earlier than peak warmth in the Northern Hemisphere. Marine ice sheet collapse is triggered with 1.5 °C model subsurface ocean warming.

19.
Protein Expr Purif ; 223: 106559, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39089400

RESUMEN

We have functionally characterized the high-affinity phosphate transporter (PiPT) from the root endophyte fungus Piriformospora indica. PiPT belongs to the major facilitator superfamily (MFS). PiPT protein was purified by affinity chromatography (Ni-NTA) and Size Exclusion Chromatography (SEC). The functionality of solubilized PiPT was determined in detergent-solubilized state by fluorescence quenching and in proteoliposomes. In the fluorescence quenching assay, PiPT exhibited a saturation concentration of approximately 2 µM, at a pH of 4.5. Proteoliposomes of size 121.6 nm radius, showed transportation of radioactive phosphate. Vmax was measured to be 232.2 ± 11 pmol/min/mg protein. We have found Km to be 45.8 ± 6.2 µM suggesting high affinity towards phosphate.


Asunto(s)
Basidiomycota , Proteínas de Transporte de Fosfato , Basidiomycota/metabolismo , Basidiomycota/química , Proteínas de Transporte de Fosfato/metabolismo , Proteínas de Transporte de Fosfato/genética , Proteínas de Transporte de Fosfato/química , Proteínas Fúngicas/química , Proteínas Fúngicas/aislamiento & purificación , Proteínas Fúngicas/metabolismo , Endófitos/metabolismo , Endófitos/química , Raíces de Plantas/microbiología , Raíces de Plantas/química , Fosfatos/metabolismo , Fosfatos/química
20.
J Electrocardiol ; 86: 153760, 2024 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-39153288

RESUMEN

BACKGROUND: Identifying bicuspid aortic valve (BAV) patients at risk for cardiac events remains challenging and the role of the electrocardiogram (ECG) has not yet been described. Therefore, this study aims to describe ECG parameters in BAV patients, and investigate their prognostic value. METHODS: In this single-center prospective study patients with BAV without a prior aortic valve replacement (AVR) were included. Transthoracic echocardiogram and 12­lead resting-ECG were obtained. Associations between ECG parameters and the composite endpoint of all-cause mortality and AVR were assessed using Cox-proportional hazard analysis. RESULTS: 120 patients with BAV were included (median age 30 years, 61% male). Median aortic jet velocity was 2.4 m/s [IQR: 1.7-3.4] and 5 patients (4%) had severe aortic regurgitation. All patients were in sinus rhythm. Any ECG abnormality was present in 57 patients (48%). Median PR-interval was 156 [IQR: 138-170] msec. A deviating QRS axis was found in 17 patients (14%) and Cornell criteria for LVH were fulfilled in 20 patients (17%). Repolarization abnormalities were present in 12 patients (10%). Median follow-up duration was 7.0 [6.3-9.8] years, during which 23 patients underwent AVR and 2 patients died. After adjusting for age, a longer PR-interval was associated with worse intervention-free survival (HR 1.02, 95% CI: 1.01-1.04). CONCLUSION: Almost half of the patients with BAV had abnormalities on their ECG. Moreover, the PR-interval may be an interesting prognostic marker for intervention-free survival in BAV patients.

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