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The natural world provides many examples of multiphase transport and reaction processes that have been optimized by evolution. These phenomena take place at multiple length and time scales and typically include gas-liquid-solid interfaces and capillary phenomena in porous media1,2. Many biological and living systems have evolved to optimize fluidic transport. However, living things are exceptionally complex and very difficult to replicate3-5, and human-made microfluidic devices (which are typically planar and enclosed) are highly limited for multiphase process engineering6-8. Here we introduce the concept of cellular fluidics: a platform of unit-cell-based, three-dimensional structures-enabled by emerging 3D printing methods9,10-for the deterministic control of multiphase flow, transport and reaction processes. We show that flow in these structures can be 'programmed' through architected design of cell type, size and relative density. We demonstrate gas-liquid transport processes such as transpiration and absorption, using evaporative cooling and CO2 capture as examples. We design and demonstrate preferential liquid and gas transport pathways in three-dimensional cellular fluidic devices with capillary-driven and actively pumped liquid flow, and present examples of selective metallization of pre-programmed patterns. Our results show that the design and fabrication of architected cellular materials, coupled with analytical and numerical predictions of steady-state and dynamic behaviour of multiphase interfaces, provide deterministic control of fluidic transport in three dimensions. Cellular fluidics may transform the design space for spatial and temporal control of multiphase transport and reaction processes.
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Células/metabolismo , Microfluídica/instrumentación , Microfluídica/métodos , Absorción Fisicoquímica , Dióxido de Carbono/metabolismo , Gases/metabolismo , Nutrientes/metabolismo , Oxígeno/metabolismo , Transpiración de Plantas , Grabación de Videodisco , Agua/metabolismoRESUMEN
The present study investigated the impact of central α2-adrenergic mechanisms on sympathetic action potential (AP) discharge, recruitment and latency strategies. We used the microneurographic technique to record muscle sympathetic nerve activity and a continuous wavelet transform to investigate postganglionic sympathetic AP firing during a baseline condition and an infusion of a α2-adrenergic receptor agonist, dexmedetomidine (10 min loading infusion of 0.225 µg kg-1; maintenance infusion of 0.1-0.5 µg kg h-1) in eight healthy individuals (28 ± 7 years, five females). Dexmedetomidine reduced mean pressure (92 ± 7 to 80 ± 8 mmHg, P < 0.001) but did not alter heart rate (61 ± 13 to 60 ± 14 bpm; P = 0.748). Dexmedetomidine reduced sympathetic AP discharge (126 ± 73 to 27 ± 24 AP 100 beats-1, P = 0.003) most strongly for medium-sized APs (normalized cluster 2: 21 ± 10 to 5 ± 5 AP 100 beats-1; P < 0.001). Dexmedetomidine progressively de-recruited sympathetic APs beginning with the largest AP clusters (12 ± 3 to 7 ± 2 clusters, P = 0.002). Despite de-recruiting large AP clusters with shorter latencies, dexmedetomidine reduced AP latency across remaining clusters (1.18 ± 0.12 to 1.13 ± 0.13 s, P = 0.002). A subset of six participants performed a Valsalva manoeuvre (20 s, 40 mmHg) during baseline and the dexmedetomidine infusion. Compared to baseline, AP discharge (Δ 361 ± 292 to Δ 113 ± 155 AP 100 beats-1, P = 0.011) and AP cluster recruitment elicited by the Valsalva manoeuvre were lower during dexmedetomidine (Δ 2 ± 1 to Δ 0 ± 2 AP clusters, P = 0.041). The reduction in sympathetic AP latency elicited by the Valsalva manoeuvre was not affected by dexmedetomidine (Δ -0.09 ± 0.07 to Δ -0.07 ± 0.14 s, P = 0.606). Dexmedetomidine reduced baroreflex gain, most strongly for medium-sized APs (normalized cluster 2: -6.0 ± 5 to -1.6 ± 2 % mmHg-1; P = 0.008). These data suggest that α2-adrenergic mechanisms within the central nervous system modulate sympathetic postganglionic neuronal discharge, recruitment and latency strategies in humans. KEY POINTS: Sympathetic postganglionic neuronal subpopulations innervating the human circulation exhibit complex patterns of discharge, recruitment and latency. However, the central neural mechanisms governing sympathetic postganglionic discharge remain unclear. This microneurographic study investigated the impact of a dexmedetomidine infusion (α2-adrenergic receptor agonist) on muscle sympathetic postganglionic action potential (AP) discharge, recruitment and latency patterns. Dexmedetomidine infusion inhibited the recruitment of large and fast conducting sympathetic APs and attenuated the discharge of medium sized sympathetic APs that fired during resting conditions and the Valsalva manoeuvre. Dexmedetomidine infusion elicited shorter sympathetic AP latencies during resting conditions but did not affect the reductions in latency that occurred during the Valsalva manoeuvre. These data suggest that α2-adrenergic mechanisms within the central nervous system modulate sympathetic postganglionic neuronal discharge, recruitment and latency strategies in humans.
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Potenciales de Acción , Agonistas de Receptores Adrenérgicos alfa 2 , Dexmedetomidina , Sistema Nervioso Simpático , Humanos , Dexmedetomidina/farmacología , Femenino , Adulto , Masculino , Agonistas de Receptores Adrenérgicos alfa 2/farmacología , Sistema Nervioso Simpático/fisiología , Sistema Nervioso Simpático/efectos de los fármacos , Potenciales de Acción/efectos de los fármacos , Potenciales de Acción/fisiología , Adulto Joven , Frecuencia Cardíaca/efectos de los fármacos , Frecuencia Cardíaca/fisiología , Presión Sanguínea/fisiología , Presión Sanguínea/efectos de los fármacos , Músculo Esquelético/fisiología , Músculo Esquelético/inervación , Músculo Esquelético/efectos de los fármacos , Receptores Adrenérgicos alfa 2/fisiología , Receptores Adrenérgicos alfa 2/metabolismoRESUMEN
Melioidosis is an emerging tropical infection caused by inhalation, inoculation, or ingestion of the flagellated, facultatively intracellular pathogen Burkholderia pseudomallei. The melioidosis case fatality rate is often high, and pneumonia, the most common presentation, doubles the risk of death. The alveolar macrophage is a sentinel pulmonary host defense cell, but the human alveolar macrophage in B. pseudomallei infection has never been studied. The objective of this study was to investigate the host-pathogen interaction of B. pseudomallei infection with the human alveolar macrophage and to determine the role of flagellin in modulating inflammasome-mediated pathways. We found that B. pseudomallei infects primary human alveolar macrophages but is gradually restricted in the setting of concurrent cell death. Electron microscopy revealed cytosolic bacteria undergoing division, indicating that B. pseudomallei likely escapes the alveolar macrophage phagosome and may replicate in the cytosol, where it triggers immune responses. In paired human blood monocytes, uptake and intracellular restriction of B. pseudomallei are similar to those observed in alveolar macrophages, but cell death is reduced. The alveolar macrophage cytokine response to B. pseudomallei is characterized by marked interleukin (IL)-18 secretion compared to monocytes. Both cytotoxicity and IL-18 secretion in alveolar macrophages are partially flagellin dependent. However, the proportion of IL-18 release that is driven by flagellin is greater in alveolar macrophages than in monocytes. These findings suggest differential flagellin-mediated inflammasome pathway activation in the human alveolar macrophage response to B. pseudomallei infection and expand our understanding of intracellular pathogen recognition by this unique innate immune lung cell.
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Burkholderia pseudomallei , Flagelina , Interacciones Huésped-Patógeno , Inflamasomas , Macrófagos Alveolares , Humanos , Macrófagos Alveolares/inmunología , Macrófagos Alveolares/microbiología , Inflamasomas/inmunología , Inflamasomas/metabolismo , Burkholderia pseudomallei/inmunología , Flagelina/inmunología , Flagelina/metabolismo , Interacciones Huésped-Patógeno/inmunología , Melioidosis/inmunología , Melioidosis/microbiología , Células CultivadasRESUMEN
Efferent muscle sympathetic nerve activity (MSNA) is under tonic baroreflex control. The arterial baroreflex exerts the strongest influence over medium-sized sympathetic action potential (AP) subpopulations in efferent MSNA recordings. Prior work from multi-unit MSNA recordings has shown baroreflex loading selectively abolishes the sympathetic response to hypoxia. The purpose of the study was to examine baroreflex control over different-sized AP clusters and characterize the neural recruitment strategies of sympathetic AP subpopulations with baroreflex and combined baroreflex/chemoreflex (i.e., hypoxia) activation. We loaded the arterial baroreceptors (intravenous phenylephrine) alone and in combination with systemic hypoxia (SpO2 80%) in 9 healthy young men. We extracted sympathetic APs using wavelet-based methodology and quantified baroreflex gain for individual AP clusters. AP baroreflex threshold gain was measured as the slope of the linear relationship between AP probability versus diastolic blood pressure for 10 normalized clusters. Baroreflex loading with phenylephrine decreased MSNA and AP firing compared to baseline (all P < 0.05). However, the phenylephrine-mediated decrease in AP firing was lost with concurrent hypoxia (P = 0.384). Compared with baseline, baroreflex loading reduced medium sized AP cluster baroreflex threshold slope (condition P = 0.005) and discharge probability (condition P < 0.0001); these reductions from baseline were maintained during simultaneous hypoxia (both P < 0.05). Present findings indicate a key modulatory role of the baroreceptors on medium-sized APs in blood pressure regulation that withstands competing signals from peripheral chemoreflex activation.
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BACKGROUND: Convalescent plasma has been widely used to treat coronavirus disease 2019 (Covid-19) under the presumption that such plasma contains potentially therapeutic antibodies to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that can be passively transferred to the plasma recipient. Whether convalescent plasma with high antibody levels rather than low antibody levels is associated with a lower risk of death is unknown. METHODS: In a retrospective study based on a U.S. national registry, we determined the anti-SARS-CoV-2 IgG antibody levels in convalescent plasma used to treat hospitalized adults with Covid-19. The primary outcome was death within 30 days after plasma transfusion. Patients who were enrolled through July 4, 2020, and for whom data on anti-SARS-CoV-2 antibody levels in plasma transfusions and on 30-day mortality were available were included in the analysis. RESULTS: Of the 3082 patients included in this analysis, death within 30 days after plasma transfusion occurred in 115 of 515 patients (22.3%) in the high-titer group, 549 of 2006 patients (27.4%) in the medium-titer group, and 166 of 561 patients (29.6%) in the low-titer group. The association of anti-SARS-CoV-2 antibody levels with the risk of death from Covid-19 was moderated by mechanical ventilation status. A lower risk of death within 30 days in the high-titer group than in the low-titer group was observed among patients who had not received mechanical ventilation before transfusion (relative risk, 0.66; 95% confidence interval [CI], 0.48 to 0.91), and no effect on the risk of death was observed among patients who had received mechanical ventilation (relative risk, 1.02; 95% CI, 0.78 to 1.32). CONCLUSIONS: Among patients hospitalized with Covid-19 who were not receiving mechanical ventilation, transfusion of plasma with higher anti-SARS-CoV-2 IgG antibody levels was associated with a lower risk of death than transfusion of plasma with lower antibody levels. (Funded by the Department of Health and Human Services and others; ClinicalTrials.gov number, NCT04338360.).
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Anticuerpos Antivirales/sangre , COVID-19/terapia , SARS-CoV-2/inmunología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , COVID-19/inmunología , COVID-19/mortalidad , Femenino , Hospitalización , Humanos , Inmunización Pasiva , Inmunoglobulina G/sangre , Masculino , Persona de Mediana Edad , Sistema de Registros , Respiración Artificial , Estudios Retrospectivos , Factores de Riesgo , Tiempo de Tratamiento , Estados Unidos/epidemiología , Adulto Joven , Sueroterapia para COVID-19RESUMEN
Sepsis is characterized by a dysfunctional host response to infection culminating in life-threatening organ failure that requires complex patient management and rapid intervention. Timely diagnosis of the underlying cause of sepsis is crucial, and identifying those at risk of complications and death is imperative for triaging treatment and resource allocation. Here, we explored the potential of explainable machine learning models to predict mortality and causative pathogen in sepsis patients. By using a modelling pipeline employing multiple feature selection algorithms, we demonstrate the feasibility of identifying integrative patterns from clinical parameters, plasma biomarkers, and extensive phenotyping of blood immune cells. While no single variable had sufficient predictive power, models that combined five and more features showed a macro area under the curve (AUC) of 0.85 to predict 90-day mortality after sepsis diagnosis, and a macro AUC of 0.86 to discriminate between Gram-positive and Gram-negative bacterial infections. Parameters associated with the cellular immune response contributed the most to models predictive of 90-day mortality, most notably, the proportion of T cells among PBMCs, together with expression of CXCR3 by CD4+ T cells and CD25 by mucosal-associated invariant T (MAIT) cells. Frequencies of Vδ2+ γδ T cells had the most profound impact on the prediction of Gram-negative infections, alongside other T-cell-related variables and total neutrophil count. Overall, our findings highlight the added value of measuring the proportion and activation patterns of conventional and unconventional T cells in the blood of sepsis patients in combination with other immunological, biochemical, and clinical parameters.
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Sepsis , Humanos , Sepsis/inmunología , Sepsis/microbiología , Masculino , Femenino , Persona de Mediana Edad , Anciano , Biomarcadores/sangre , Receptores CXCR3/metabolismo , Aprendizaje Automático , Subunidad alfa del Receptor de Interleucina-2/sangre , Subunidad alfa del Receptor de Interleucina-2/inmunología , Inmunidad Celular , Linfocitos T CD4-Positivos/inmunología , Linfocitos T/inmunología , Pronóstico , Infecciones por Bacterias Gramnegativas/inmunologíaRESUMEN
Malaria cases are frequently recorded in the Ethiopian highlands even at altitudes above 2000 m. The epidemiology of malaria in the Ethiopian highlands, and, in particular, the role of importation by human migration from the highly endemic lowlands is not well understood. We sequenced 187 Plasmodium falciparum samples from two sites in the Ethiopian highlands, Gondar (n = 159) and Ziway (n = 28), using a multiplexed droplet digital PCR (ddPCR)-based amplicon sequencing method targeting 35 microhaplotypes and drug resistance loci. Here, we characterize the parasite population structure and genetic relatedness. We identify moderate parasite diversity (mean HE : 0.54) and low infection complexity (74.9% monoclonal). A significant percentage of infections share microhaplotypes, even across transmission seasons and sites, indicating persistent local transmission. We identify multiple clusters of clonal or near-clonal infections, highlighting high genetic relatedness. Only 6.3% of individuals diagnosed with P. falciparum reported recent travel. Yet, in clonal or near-clonal clusters, infections of travellers were frequently observed first in time, suggesting that parasites may have been imported and then transmitted locally. 31.1% of infections are pfhrp2-deleted and 84.4% pfhrp3-deleted, and 28.7% have pfhrp2/3 double deletions. Parasites with pfhrp2/3 deletions and wild-type parasites are genetically distinct. Mutations associated with resistance to sulphadoxine-pyrimethamine or suggested to reduce sensitivity to lumefantrine are observed at near-fixation. In conclusion, genomic data corroborate local transmission and the importance of intensified control in the Ethiopian highlands.
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Malaria Falciparum , Malaria , Parásitos , Animales , Humanos , Plasmodium falciparum/genética , Proteínas Protozoarias/genética , Antígenos de Protozoos/genética , Etiopía/epidemiología , Eliminación de Gen , Malaria Falciparum/genética , Malaria/genéticaRESUMEN
BACKGROUND: Radiotherapy delivery regimens can vary between a single fraction (SF) and multiple fractions (MF) given daily for up to several weeks depending on the location of the cancer or metastases. With limited evidence comparing fractionation regimens for oligometastases, there is support to explore toxicity levels to nearby organs at risk as a primary outcome while using SF and MF stereotactic ablative radiotherapy (SABR) as well as explore differences in patient-reported quality of life and experience. METHODS: This study will randomize 598 patients in a 1:1 ratio between the standard arm (MF SABR) and the experimental arm (SF SABR). This trial is designed as two randomized controlled trials within one patient population for resource efficiency. The primary objective of the first randomization is to determine if SF SABR is non-inferior to MF SABR, with respect to healthcare provider (HCP)-reported grade 3-5 adverse events (AEs) that are related to SABR. Primary endpoint is toxicity while secondary endpoints include lesional control rate (LCR), and progression-free survival (PFS). The second randomization (BC Cancer sites only) will allocate participants to either complete quality of life (QoL) questionnaires only; or QoL questionnaires and a symptom-specific survey with symptom-guided HCP intervention. The primary objective of the second randomization is to determine if radiation-related symptom questionnaire-guided HCP intervention results in improved reported QoL as measured by the EuroQoL-5-dimensions-5levels (EQ-5D-5L) instrument. The primary endpoint is patient-reported QoL and secondary endpoints include: persistence/resolution of symptom reporting, QoL, intervention cost effectiveness, resource utilization, and overall survival. DISCUSSION: This study will compare SF and MF SABR in the treatment of oligometastases and oligoprogression to determine if there is non-inferior toxicity for SF SABR in selected participants with 1-5 oligometastatic lesions. This study will also compare patient-reported QoL between participants who receive radiation-related symptom-guided HCP intervention and those who complete questionnaires alone. TRIAL REGISTRATION: Clinicaltrials.gov identifier: NCT05784428. Date of Registration: 23 March 2023.
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Neoplasias , Radiocirugia , Humanos , Neoplasias/mortalidad , Neoplasias/patología , Neoplasias/radioterapia , Supervivencia sin Progresión , Calidad de Vida , Radiocirugia/efectos adversos , Radiocirugia/métodos , Estudios de Equivalencia como AsuntoRESUMEN
Severe mental ill health (SMI) is associated with excess mortality, and poor diet is one associated modifiable risk factor. This study investigated factors associated with low consumption of fruit and vegetables among people with SMI (N = 9914). A total of 8.4% of participants ate no portions per day, while only 15% ate 5 + portions. Individuals who never consumed fruit and vegetables or ate < 5 portions per day were more likely to be male, younger than 65, unemployed, experience poorer general health, or perceive health as unimportant. Poor diet is common among people with SMI and tailored dietary improvement interventions are required.
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Frutas , Verduras , Humanos , Masculino , Femenino , Dieta , Salud Mental , Factores de Riesgo , Conducta AlimentariaRESUMEN
Electrochemical reactors utilizing flow-through electrodes (FTEs) provide an attractive path toward the efficient utilization of electrical energy, but their commercial viability and ultimate adoption hinge on attaining high currents to drive productivity and cost competitiveness. Conventional FTEs composed of random, porous media provide limited opportunity for architectural control and engineering of microscale transport. Alternatively, the design freedom engendered by additively manufacturing FTEs yields additional opportunities to further drive performance via flow engineering. Through experiment and validated continuum computation we analyze the mass transfer in three-dimensional (3D)-printed porous FTEs with periodic lattice structures and show that, in contrast to conventional electrodes, the mesoscopic length scales in 3D-printed electrodes lead to an increase in the mass correlation exponent as inertial flow effects dominate. The inertially enhanced mass transport yields mass transfer coefficients that exceed previously reported 3D-printed FTEs by 10 to 100 times, bringing 3D-printed FTE performance on par with conventional materials.
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BACKGROUND: Children with disabilities generally face poorer oral health outcomes compared with their non-disabled peers due to a range of factors including inadequate oral hygiene, infrequent dental visits and systemic barriers in accessing care. AIM: This ethnographic study explored the perspectives of caregivers and professionals to identify the ways that children with disabilities are included in oral health. DESIGN: A purposive sample of 10 caregivers, all mothers with disabled children aged 9-15 years, five healthcare providers and five educators in Saudi Arabia, participated. Data collection used participant observation and semi-structured in-depth interviews. Data were analysed using reflexive thematic analysis. RESULTS: The findings suggest that mothers lacked a supportive environment to develop their skills and knowledge about oral health care, preventing them from including their children in oral health. Inaccessible services added to the exclusion of both mothers and children. Some dental professionals exhibited poor communication skills and discriminatory attitudes towards the children and problematising mothers. Educators tended to discuss disabled children in terms of inability, displaying a deficit approach to impairment. CONCLUSIONS: The evidence suggests the exclusion of mothers from oral health. This has an impact on how they enable their children. Recommendations include adopting a social model of disability in dental education and policies in Saudi Arabia to address inequalities. Provision of support, education and focusing on societal barriers moves towards inclusion rather than conceptualising disability as an individual problem.
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BACKGROUND: Poor oral health is common among older adults residing in care homes impacting their diet, quality of life, self-esteem, general health and well-being. The care home setting is complex and many factors may affect the successful implementation of oral care interventions. Exploring these factors and their embedded context is key to understanding how and why interventions may or may not be successfully implemented within their intended setting. OBJECTIVES: This methodology paper describes the approach to a theoretically informed process evaluation alongside a pragmatic randomised controlled trial, so as to understand contextual factors, how the intervention was implemented and important elements that may influence the pathways to impact. MATERIALS AND METHODS: SENIOR is a pragmatic randomised controlled trial designed to improve the oral health of care home residents in the United Kingdom. The trial uses a complex intervention to promote and provide oral care for residents, including education and training for staff. RESULTS: An embedded, theoretically informed process evaluation, drawing on the PAHRIS framework and utilising a qualitative approach, will help to understand the important contextual factors within the care home that influence both the trial processes and the implementation of the intervention. CONCLUSION: Utilising an implementation framework as the basis for a theoretically informed process evaluation provides an approach that specifically focuses on the contextual factors that may influence and shape the pathways to impact a given complex intervention a priori, while also providing an understanding of how and why an intervention may be effective. This contrasts with the more common post hoc approach that only focuses on implementation after the empirical results have emerged.
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Casas de Salud , Salud Bucal , Humanos , Anciano , Calidad de Vida , Reino Unido , EscolaridadRESUMEN
OBJECTIVES: SENIOR (uSing rolE-substitutioN In care homes to improve oRal health) is a randomised controlled trial designed to determine whether role substitution could improve oral health for this population. A parallel process evaluation was undertaken to understand context. This paper reports on the first phase of the process evaluation. BACKGROUND: The oral health and quality-of-life of older adults residing in care homes is poorer than those in the community. Oral health care provision is often unavailable and a concern and challenge for managers. The use of Dental Therapists and Dental Nurses rather than dentists could potentially meet these needs. MATERIALS AND METHODS: Semi-structured interviews were conducted with 21 key stakeholders who either worked or had experience of dependent care settings. Questions were theoretically informed by the: Promoting Action on Research Implementation in Health Services (PAHRIS) framework. The focus was on contextual factors that could influence adoption in practice and the pathway-to-impact. Interviews were fully transcribed and analysed thematically. RESULTS: Three themes (receptive context, culture, and leadership) and 11 codes were generated. Data show the complexity of the setting and contextual factors that may work as barriers and facilitators to intervention delivery. Managers are aware of the issues regarding oral health and seek to provide best care, but face many challenges including staff turnover, time pressures, competing needs, access to services, and financial constraints. Dental professionals recognise the need for improvement and view role substitution as a viable alternative to current practice. CONCLUSION: Although role substitution could potentially meet the needs of this population, an in-depth understanding of contextual factors appeared important in understanding intervention delivery and implementation.
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The sympathetic nervous system represents a critical mechanism for homoeostatic blood pressure regulation in humans. This review focuses on age-related alterations in neurocirculatory regulation in men and women by highlighting human studies that examined the relationship between muscle sympathetic nerve activity (MSNA) acquired by microneurography and circulatory variables (e.g., blood pressure, vascular resistance). We frame this review with epidemiological evidence highlighting sex-specific patterns in age-related blood pressure increases in developed nations. Indeed, young women exhibit lower blood pressure than men, but women demonstrate larger blood pressure increases with age, such that by about age 60 years, blood pressure is greater in women. Sympathetic neurocirculatory mechanisms contribute to sex differences in blood pressure rises with age. Muscle sympathetic nerve activity increases with age in both sexes, but women demonstrate greater age-related increases. The circulatory adjustments imposed by MSNA - referred to as neurovascular transduction or autonomic (sympathetic) support of blood pressure - differ in men and women. For example, whereas young men demonstrate a positive relationship between resting MSNA and vascular resistance, this relationship is absent in young women due to beta-2 adrenergic vasodilation, which offsets alpha-adrenergic vasoconstriction. However, post-menopausal women demonstrate a positive relationship between MSNA and vascular resistance due to a decline in beta-2 adrenergic vasodilatory mechanisms. Emerging data suggest that greater aerobic fitness appears to modulate neurocirculatory regulation, at least in young, healthy men and women. This review also highlights recent advances in microneurographic recordings of sympathetic action potential discharge, which may nuance our understanding of age-related alterations in sympathetic neurocirculatory regulation in humans.
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Sistema Nervioso Simpático/fisiopatología , Envejecimiento , Femenino , Humanos , Masculino , Factores SexualesRESUMEN
During hypoxic exposure, humans with high-affinity hemoglobin (and compensatory polycythemia) have blunted increases in heart rate compared with healthy humans with typical oxyhemoglobin dissociation curves. This response may be associated with altered autonomic control of heart rate. Our hypothesis-generating study aimed to investigate cardiac baroreflex sensitivity and heart rate variability among nine humans with high-affinity hemoglobin [6 females, O2 partial pressure at 50% [Formula: see text] (P50) = 16 ± 1 mmHg] compared with 12 humans with typical affinity hemoglobin (6 F, P50 = 26 ± 1 mmHg). Participants breathed normal room air for a 10-min baseline, followed by 20 min of isocapnic hypoxic exposure, designed to lower the arterial partial pressure O2 ([Formula: see text]) to â¼50 mmHg. Beat-by-beat heart rate and arterial blood pressure were recorded. Data were averaged in 5-min periods throughout the hypoxia exposure, beginning with the last 5 min of baseline in normoxia. Spontaneous cardiac baroreflex sensitivity and heart rate variability were determined using the sequence method and the time and frequency domain analyses, respectively. Cardiac baroreflex sensitivity was lower in humans with high-affinity hemoglobin than controls at baseline and during isocapnic hypoxic exposure (normoxia: 7 ± 4 vs. 16 ± 10 ms/mmHg, hypoxia minutes 15-20: 4 ± 3 vs. 14 ± 11 ms/mmHg; group effect: P = 0.02, high-affinity hemoglobin vs. control, respectively). Heart rate variability calculated in both the time (standard deviation of the N-N interval) and frequency (low frequency) domains was lower in humans with high-affinity hemoglobin than in controls (all P < 0.05). Our data suggest that humans with high-affinity hemoglobin may have attenuated cardiac autonomic function.
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Policitemia , Femenino , Humanos , Corazón , Sistema Nervioso Autónomo , Presión Arterial , Frecuencia Cardíaca/fisiología , Hipoxia , Barorreflejo/fisiología , Presión SanguíneaRESUMEN
BACKGROUND/PURPOSE: Post radiation mucosal ulcers (PRMU) after treatment for oropharyngeal squamous cell carcinoma (OPSCC) can have a huge negative impact on patients' quality of life, but little is known concerning risk factors and the impact of fraction size. Therefore, the goal of this study was to determine the pattern of PRMU development and to identify risk factors after a hypofractionated stereotactic body radiotherapy boost (SBRT) compared to conventionally fractionated radiotherapy for OPSCC. MATERIAL AND METHODS: We performed a retrospective cohort study (N = 332) of OPSCC patients with ≥ 1-year disease-free survival, treated with 46 Gy Intensity Modulated Radiotherapy (IMRT) (2 Gy fractions) followed by either an SBRT boost of 16.5 Gy (5.5 Gy fractions) (N = 180), or 24 Gy IMRT (2 Gy fractions) (N = 152). PRMU (grade ≥ 2) was scored when observed > three months after the last radiotherapy (RT) fraction (CTCAE v5.0). Potential risk factors were analyzed with Cox regression models using death as competing risk. Dose at the PRMU site was calculated by projecting delineated PRMU on the planning CT. RESULTS: All cases of PRMU (N = 64) occurred within 24 months; all were grade 2. The cumulative incidence at 2 years in the SBRT boost group was 26% (N = 46) vs. 12% (N = 18) for conventional fractionation (p = 0.003). Most PRMU developed within nine months (N = 48). PRMU occurring > nine months (N = 16) were mainly observed in the SBRT boost group (N = 15). Sex (p = 0.048), acute tube feeding (p = < 0.001), tumor subsite tonsil (p = 0.001), and N stage (p = 0.017) were associated with PRMU risk at multivariable regression in the hypofractionated SBRT boost group. All 25 delineated PRMU were located within the high dose regions. CONCLUSION: The risk of PRMU should be included in the cost benefit analysis when considering future research using a hypofractionated SBRT boost for OPSCC patients.
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Carcinoma , Neoplasias Orofaríngeas , Radiocirugia , Radioterapia de Intensidad Modulada , Humanos , Estudios Retrospectivos , Calidad de Vida , Úlcera/etiología , Fraccionamiento de la Dosis de Radiación , Radiocirugia/efectos adversos , Neoplasias Orofaríngeas/radioterapia , Neoplasias Orofaríngeas/etiología , Radioterapia de Intensidad Modulada/efectos adversos , Resultado del TratamientoRESUMEN
INTRODUCTION: Arsenic methylation converts inorganic arsenic (iAs) to monomethyl (MMA) and dimethyl (DMA) arsenic compounds. Body mass index (BMI) has been positively associated with arsenic methylation efficiency (higher DMA%) in adults, but evidence in pregnancy is inconsistent. We estimated associations between anthropometric measures and arsenic methylation among pregnant women in rural northern Bangladesh. METHODS: We enrolled pregnant women (n = 784) (median [IQR] gestational week: 14 [13, 15]) in Gaibandha District, Bangladesh from 2018 to 2019. Anthropometric measures were BMI, subscapular and triceps skinfold thicknesses, and mid-upper arm circumference (MUAC), fat area (MUAFA), and muscle area (MUAMA). Arsenic methylation measures were urinary iAs, MMA, and DMA divided by their sum and multiplied by 100 (iAs%, MMA%, and DMA%), primary methylation index (MMA/iAs; PMI), and secondary methylation index (DMA/MMA; SMI). In complete cases (n = 765 [97.6%]), we fitted linear, beta, and Dirichlet regression models to estimate cross-sectional differences in iAs%, MMA%, DMA%, PMI, and SMI per IQR-unit difference in each anthropometric measure, adjusting for drinking water arsenic, age, gestational age, education, living standards index, and plasma folate, vitamin B12, and homocysteine. RESULTS: Median (IQR) BMI, subscapular skinfold thickness, triceps skinfold thickness, MUAC, MUAFA, and MUAMA were 21.5 (19.4, 23.8) kg/m2, 17.9 (13.2, 24.2) mm, 14.2 (10.2, 18.7) mm, 25.9 (23.8, 28.0) cm, 15.3 (10.5, 20.3) cm2, and 29.9 (25.6, 34.2) cm2, respectively. Median (IQR) iAs%, MMA%, DMA%, PMI, and SMI were 12.0 (9.3, 15.2)%, 6.6 (5.3, 8.3)%, 81.0 (77.1, 84.6)%, 0.6 (0.4, 0.7), and 12.2 (9.3, 15.7), respectively. In both unadjusted and adjusted linear models, all anthropometric measures were negatively associated with iAs%, MMA%, and PMI and positively associated with DMA% and SMI. For example, fully adjusted mean differences (95% CI) in DMA% per IQR-unit difference in BMI, subscapular skinfolds thickness, triceps skinfold thickness, MUAC, MUAFA, and MUAMA were 1.72 (1.16, 2.28), 1.58 (0.95, 2.21), 1.74 (1.11, 2.37), 1.45 (0.85, 2.06), 1.70 (1.08, 2.31), and 0.70 (0.13, 1.27) pp, respectively. CONCLUSIONS: Anthropometric measures were positively associated with arsenic methylation efficiency among pregnant women in the early second trimester.
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Arsénico , Arsenicales , Adulto , Humanos , Femenino , Embarazo , Arsénico/análisis , Metilación , Mujeres Embarazadas , Bangladesh , Estudios Transversales , Exposición a Riesgos Ambientales/análisisRESUMEN
Although body image concerns (BIC) are recognized as a core driver in the development of disordered eating behaviors, the combined role of various types of BIC remains underexamined. This study relied on latent profile analysis to identify the main configurations of self-reported BIC (i.e., body checking and avoidance, perceived physical appearance, and fear of negative appearance evaluation) observed in a sample of 419 French-Canadian individuals (Mage = 26.59, SDage = 9.23). The role of body mass index, sex, and age on profile membership was also examined, as well as the relation between profile membership and disordered eating behaviors (i.e., dieting, bulimia and food preoccupation, and oral control). Six distinct BIC profiles differing in terms of shape and level were identified, with women being more likely to display a profile characterized by higher levels of BIC. In turn, profiles characterized by higher levels of BIC were associated with more disordered eating behaviors. The present study can broaden our understanding of the onset and maintenance of disordered eating behaviors and inspire the development of more tailored body-image interventions.
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OBJECTIVES: This study aimed to evaluate whether a measure of subjective cognitive decline (SCD), the Patient-Reported Outcomes Measurement Information System (PROMIS) Applied Cognition-Abilities questionnaire, was associated with postoperative delirium. It was hypothesized that delirium during the surgical hospitalization would be associated with a decrease in subjective cognition up to 6 months after cardiac surgery. DESIGN: This was a secondary analysis of data from the Minimizing Intensive Care Unit Neurological Dysfunction with Dexmedetomidine-induced Sleep randomized, placebo-controlled, parallel-arm superiority trial. SETTING: Data from patients recruited between March 2017 and February 2022 at a tertiary medical center in Boston, Massachusetts were analyzed in February 2023. PARTICIPANTS: Data from 337 patients aged 60 years or older who underwent cardiac surgery with cardiopulmonary bypass were included. INTERVENTIONS: Patients were assessed preoperatively and postoperatively at 30, 90, and 180 days using the subjective PROMIS Applied Cognition-Abilities and telephonic Montreal Cognitive Assessment. MEASUREMENT AND MAIN RESULTS: Postoperative delirium occurred within 3 days in 39 participants (11.6%). After adjusting for baseline function, participants who developed postoperative delirium self-reported worse cognitive function (mean difference [MD] -2.64 [95% CI -5.25, -0.04]; p = 0.047) up to 180 days after surgery, as compared with nondelirious patients. This finding was consistent with those obtained from objective t-MoCA assessments (MD -0.77 [95% CI -1.49, -0.04]; p = 0.04). CONCLUSIONS: In this cohort of older patients undergoing cardiac surgery, in-hospital delirium was associated with SCD up to 180 days after surgery. This finding suggested that measures of SCD may enable population-level insights into the burden of cognitive decline associated with postoperative delirium.
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Procedimientos Quirúrgicos Cardíacos , Disfunción Cognitiva , Delirio , Dexmedetomidina , Delirio del Despertar , Humanos , Anciano , Dexmedetomidina/efectos adversos , Delirio/inducido químicamente , Delirio/diagnóstico , Delirio/epidemiología , Procedimientos Quirúrgicos Cardíacos/efectos adversos , Disfunción Cognitiva/inducido químicamente , Disfunción Cognitiva/diagnóstico , Disfunción Cognitiva/epidemiología , Unidades de Cuidados Intensivos , Sueño , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/prevención & controlRESUMEN
Patients with obstructive sleep apnea (OSA) have a heightened risk of developing cardiovascular diseases, namely hypertension. While seminal evidence indicates a causal role for sympathetic nerve activity in the hypertensive phenotype commonly observed in patients with OSA, no studies have investigated potential sex differences in the sympathetic regulation of blood pressure in this population. Supporting this exploration are large-scale observational data, as well as controlled interventional studies in healthy adults, indicating that sleep disruption increases blood pressure to a greater extent in females relative to males. Furthermore, females with severe OSA demonstrate a more pronounced hypoxic burden (i.e., disease severity) during rapid eye movement sleep when sympathetic nerve activity is greatest. These findings would suggest that females are at greater risk for the hemodynamic consequences of OSA and related sleep disruption. Accordingly, the purpose of this review is three-fold: (1) to review the literature linking sympathetic nerve activity to hypertension in OSA, (2) to highlight recent experimental data supporting the hypothesis of sex differences in the regulation of sympathetic nerve activity in OSA, and (3) to discuss the potential sex differences in peripheral adrenergic signaling that may contribute to, or offset, cardiovascular risk in patients with OSA.