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1.
Nature ; 591(7849): 229-233, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33692560

RESUMEN

As the field of artificial intelligence advances, the demand for algorithms that can learn quickly and efficiently increases. An important paradigm within artificial intelligence is reinforcement learning1, where decision-making entities called agents interact with environments and learn by updating their behaviour on the basis of the obtained feedback. The crucial question for practical applications is how fast agents learn2. Although various studies have made use of quantum mechanics to speed up the agent's decision-making process3,4, a reduction in learning time has not yet been demonstrated. Here we present a reinforcement learning experiment in which the learning process of an agent is sped up by using a quantum communication channel with the environment. We further show that combining this scenario with classical communication enables the evaluation of this improvement and allows optimal control of the learning progress. We implement this learning protocol on a compact and fully tunable integrated nanophotonic processor. The device interfaces with telecommunication-wavelength photons and features a fast active-feedback mechanism, demonstrating the agent's systematic quantum advantage in a setup that could readily be integrated within future large-scale quantum communication networks.

2.
Nitric Oxide ; 146: 58-63, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38583684

RESUMEN

Nitric oxide was first identified as a novel and effective treatment for persistent pulmonary hypertension of the newborn (PPHN), and has since been found to be efficacious in treating acute respiratory distress syndrome (ARDS) and pulmonary hypertension. Physicians and researchers have also found it shows promise in resource-constrained settings, both within and outside of the hospital, such as in high altitude pulmonary edema (HAPE) and COVID-19. The treatment has been well tolerated in these settings, and is both efficacious and versatile when studied across a variety of clinical environments. Advancements in inhaled nitric oxide continue, and the gas is worthy of investigation as physicians contend with new respiratory and cardiovascular illnesses, as well as unforeseen logistical challenges.


Asunto(s)
COVID-19 , Óxido Nítrico , Humanos , Óxido Nítrico/administración & dosificación , Óxido Nítrico/metabolismo , Óxido Nítrico/uso terapéutico , SARS-CoV-2 , Mal de Altura/tratamiento farmacológico , Síndrome de Circulación Fetal Persistente/tratamiento farmacológico , Hipertensión Pulmonar/tratamiento farmacológico , Administración por Inhalación , Edema Pulmonar
3.
J Neurosci Res ; 100(5): 1128-1139, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-31044457

RESUMEN

Significant progress has been made toward improving both the acquisition of clinical diffusion-weighted imaging (DWI) data and its analysis in the uninjured brain, through various techniques including a large number of model-based solutions that have been proposed to fit for multiple tissue compartments, and multiple fibers per voxel. While some of these techniques have been applied to clinical traumatic brain injury (TBI) research, the majority of these technological enhancements have yet to be fully implemented in the preclinical arena of TBI animal model-based research. In this review, we describe the requirement for preclinical, MRI-based efforts to provide systematic confirmation of the applicability of some of these models as indicators of tissue pathology within the injured brain. We review how current DWI techniques are currently being used in animal TBI models, and describe how both acquisition and analytic techniques could be extended to leverage the progress made in clinical work. Finally, we highlight remaining gaps in the preclinical pipeline from data acquisition to final analysis that currently have no real, preclinical-based correlate.


Asunto(s)
Lesiones Traumáticas del Encéfalo , Imagen por Resonancia Magnética , Animales , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Lesiones Traumáticas del Encéfalo/diagnóstico por imagen , Lesiones Traumáticas del Encéfalo/patología , Imagen de Difusión por Resonancia Magnética , Modelos Animales de Enfermedad , Imagen por Resonancia Magnética/métodos
4.
Am J Emerg Med ; 58: 5-8, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35623183

RESUMEN

BACKGROUND: Inhaled nitric oxide (iNO) is a selective pulmonary vasodilator and mild bronchodilator that has been shown to improve systemic oxygenation, but has rarely been administered in the Emergency Department (ED). In addition to its favorable pulmonary vascular effects, in-vitro studies report that NO donors can inhibit replication of viruses, including SARS Coronavirus 2 (SARS-CoV-2). This study evaluated the administration of high-dose iNO by mask in spontaneously breathing emergency department (ED) patients with respiratory symptoms attributed to Coronavirus disease 2019 (COVID-19). METHODS: We designed a randomized clinical trial to determine whether 30 min of high dose iNO (250 ppm) could be safely and practically administered by emergency physicians in the ED to spontaneously-breathing patients with respiratory symptoms attributed to COVID-19. Our secondary goal was to learn if iNO could prevent the progression of mild COVID-19 to a more severe state. FINDINGS: We enrolled 47 ED patients with acute respiratory symptoms most likely due to COVID-19: 25 of 47 (53%) were randomized to the iNO treatment group; 22 of 47 (46%) to the control group (supportive care only). All patients tolerated the administration of high-dose iNO in the ED without significant complications or symptoms. Five patients receiving iNO (16%) experienced asymptomatic methemoglobinemia (MetHb) > 5%. Thirty-four of 47 (72%) subjects tested positive for SARS-CoV-2: 19 of 34 were randomized to the iNO treatment group and 15 of 34 subjects to the control group. Seven of 19 (38%) iNO patients returned to the ED, while 4 of 15 (27%) control patients did. One patient in each study arm was hospitalized: 5% in iNO treatment and 7% in controls. One patient was intubated in the iNO group. No patients in either group died. The differences between these groups were not significant. CONCLUSION: A single dose of iNO at 250 ppm was practical and not associated with any significant adverse effects when administered in the ED by emergency physicians. Local disease control led to early study closure and prevented complete testing of COVID-19 safety and treatment outcomes measures.


Asunto(s)
COVID-19 , Insuficiencia Respiratoria , Administración por Inhalación , Servicio de Urgencia en Hospital , Humanos , Óxido Nítrico/uso terapéutico , Insuficiencia Respiratoria/terapia , SARS-CoV-2
5.
Aging Ment Health ; 25(8): 1433-1441, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-32223428

RESUMEN

OBJECTIVES: People who are living with dementia typically experience difficulties in completing multi-step, everyday tasks. However, digital technology such as touchscreen tablets provide a means of delivering concise personalised prompts that combine audio, text and pictures. This study was one component of a broader, mixed methods study that tested how an application (app) -based prompter running on a touchscreen tablet computer could support everyday activities in individuals with mild to moderate dementia. In this study we set out to understand the experiences of people living with dementia and their primary carer in using the prompter over a four-week period. METHOD: We collected qualitative data using semi-structured interviews from 26 dyads, composed of a person living with dementia and their carer. Dyads were interviewed at the start and end of this period. Transcripts were then analysed using thematic analysis. RESULTS: The study identified three overarching themes related to: participants' attitudes towards the technology; their judgements about how useful the prompter would be; and the emotional impact of using it. CONCLUSION: Consistent with the Technology Acceptance Model, carers and participants were influenced by their approaches to technology and determined the usefulness of the prompter according to whether it worked for them and fitted into their routines. In addition, participants' decisions about using the prompter were also determined by the extent to which doing so would impact on their self-identity.


Asunto(s)
Cuidadores , Demencia , Humanos , Tecnología
6.
Wilderness Environ Med ; 31(1): 38-43, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32057631

RESUMEN

INTRODUCTION: High altitude headache (HAH) and acute mountain sickness (AMS) are common pathologies at high altitudes. There are similarities between AMS and migraine headaches, with nausea being a common symptom. Several studies have shown ibuprofen can be effective for AMS prophylaxis, but few have addressed treatment. Metoclopramide is commonly administered for migraine headaches but has not been evaluated for HAH or AMS. We aimed to evaluate metoclopramide and ibuprofen for treatment of HAH and AMS. METHODS: We performed a prospective, double-blinded, randomized, field-based clinical trial of metoclopramide and ibuprofen for the treatment of HAH and AMS in 47 adult subjects in the Mount Everest region of Nepal. Subjects received either 400 mg ibuprofen or 10 mg metoclopramide in a 1-time dose. Lake Louise Score (LLS) and visual analog scale of symptoms were measured before and at 30, 60, and 120 min after treatment. RESULTS: Subjects in both the metoclopramide and ibuprofen arms reported reduced headache severity and nausea compared to pretreatment values at 120 min. The ibuprofen group reported 22 mm reduction in headache and 6 mm reduction in nausea on a 100 mm visual analog scale at 120 min. The metoclopramide group reported 23 mm reduction in headache and 14 mm reduction in nausea. The ibuprofen group reported an average 3.5-point decrease on LLS, whereas the metoclopramide group reported an average 2.0-point decrease on LLS at 120 min. CONCLUSIONS: Metoclopramide and ibuprofen may be effective alternative treatment options in HAH and AMS, especially for those patients who additionally report nausea.


Asunto(s)
Mal de Altura/prevención & control , Inhibidores de la Ciclooxigenasa/uso terapéutico , Antagonistas de los Receptores de Dopamina D2/uso terapéutico , Cefalea/prevención & control , Ibuprofeno/uso terapéutico , Metoclopramida/uso terapéutico , Adulto , Mal de Altura/tratamiento farmacológico , Antiinflamatorios no Esteroideos/uso terapéutico , Antieméticos/uso terapéutico , Método Doble Ciego , Femenino , Cefalea/tratamiento farmacológico , Humanos , Masculino , Persona de Mediana Edad , Montañismo , Nepal , Estudios Prospectivos , Resultado del Tratamiento , Adulto Joven
7.
Org Biomol Chem ; 17(38): 8716-8720, 2019 10 14.
Artículo en Inglés | MEDLINE | ID: mdl-31538639

RESUMEN

Nicotinamide adenine dinucleotide, NAD+, is an essential cofactor and substrate for many cellular enzymes. Its sustained intracellular levels have been linked to improved physiological end points in a range of metabolic diseases. Biosynthetic precursors to NAD+ include nicotinic acid, nicotinamide, the ribosylated parents and the phosphorylated form of the ribosylated parents. By combining solvent-assisted mechanochemistry and sealed reaction conditions, access to the ribosylated NAD+ precursors and to the isotopologues of NAD+ precursors was achieved in high yields and levels of purity. The latter is critical as it offers means to better trace biosynthetic pathways to NAD+, investigate the multifaceted roles of the intracellular NAD+ pools, and better exploit NAD+ biology.


Asunto(s)
NAD/síntesis química , Estructura Molecular , NAD/química
9.
Eur J Clin Microbiol Infect Dis ; 37(5): 993, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29404837

RESUMEN

In the original version of this article, the word "flagellin" is not correct. The correct word should be "P66" throughout the body of the article.

10.
Eur J Clin Microbiol Infect Dis ; 37(4): 701-709, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29282568

RESUMEN

Laboratory diagnosis of Lyme disease is difficult and presently dependent on detecting Borrelia burgdorferi-specific antibodies in patient serum with the disadvantage that the immune response to B. burgdorferi can be weak or variable, or alternatively, the slow and inefficient culture confirmation of B. burgdorferi. PCR tests have previously shown poor sensitivity and are not routinely used for diagnosis. We developed a sensitive and specific Lyme Multiplex PCR-dot blot assay (LM-PCR assay) applicable to blood and urine samples to supplement western blot (WB) serological tests for detecting B. burgdorferi infection. The LM-PCR assay utilizes specific DNA hybridization to purify B. burgdorferi DNA followed by PCR amplification of p66 [corrected] and OspA gene fragments and their detection by southern dot blots. Results of the assay on 107 and 402 clinical samples from patients with suspected Lyme disease from Houston, Texas or received at the IGeneX laboratory in Palo Alto, California, respectively, were analyzed together with WB findings. The LM-PCR assay was highly specific for B. burgdorferi. In the Texas samples, 23 (21.5%) patients antibody-negative in WB assays by current US Centers for Disease Control (CDC) recommended criteria were positive by LM-PCR performed on urine, serum or whole blood samples. With IGeneX samples, of the 402 LM-PCR positive blood samples, only 70 met the CDC criteria for positive WBs, while 236 met IGeneX criteria for positive WB. Use of the LM-PCR assay and optimization of current CDC serological criteria can improve the diagnosis of Lyme disease.


Asunto(s)
Borrelia burgdorferi/genética , ADN Bacteriano , Enfermedad de Lyme/diagnóstico , Enfermedad de Lyme/microbiología , Reacción en Cadena de la Polimerasa/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Antibacterianos/sangre , Borrelia burgdorferi/inmunología , Borrelia burgdorferi/aislamiento & purificación , Niño , Preescolar , ADN Bacteriano/sangre , ADN Bacteriano/orina , Humanos , Lactante , Recién Nacido , Límite de Detección , Enfermedad de Lyme/inmunología , Persona de Mediana Edad , Sensibilidad y Especificidad , Pruebas Serológicas/métodos , Adulto Joven
11.
Aging Ment Health ; 22(8): 990-998, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-28541798

RESUMEN

OBJECTIVES: To identify feasible models of intergenerational care programmes, that is, care of children and older people in a shared setting, to determine consumer preferences and willingness to pay. METHOD: Feasible models were constructed in extensive consultations with a panel of experts using a Delphi technique (n = 23) and were considered based on their practical implementation within an Australian setting. This informed a survey tool that captured the preferences and willingness to pay for these models by potential consumers, when compared to the status quo. Information collected from the surveys (n = 816) was analysed using regression analysis to identify fundamental drivers of preferences and the prices consumers were willing to pay for intergenerational care programmes. RESULTS: The shared campus and visiting models were identified as feasible intergenerational care models. Key attributes of these models included respite day care; a common educational pedagogy across generations; screening; monitoring; and evaluation of participant outcomes. Although parents were more likely to take up intergenerational care compared to the status quo, adult carers reported a higher willingness to pay for these services. Educational attainment also influenced the likely uptake of intergenerational care. CONCLUSIONS: The results of this study show that there is demand for the shared campus and the visiting campus models among the Australian community. The findings support moves towards consumer-centric models of care, in line with national and international best practice. This consumer-centric approach is encapsulated in the intergenerational care model and enables greater choice of care to match different consumer demands.


Asunto(s)
Cuidado del Niño/organización & administración , Disfunción Cognitiva/rehabilitación , Comportamiento del Consumidor , Centros de Día/organización & administración , Modelos Organizacionales , Cuidados Intermitentes/organización & administración , Adulto , Anciano , Australia , Niño , Técnica Delphi , Encuestas de Atención de la Salud , Humanos , Apoyo Social
12.
Public Health ; 164: 57-67, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30189389

RESUMEN

OBJECTIVES: While the universal prevalence of unhealthy lifestyle behaviours is high, cultural capital as a non-material resource shaping individuals' tastes can provide a substantial insight into different lifestyle behaviour choices. The aim of the present systematic review was to examine the evidence on the association between the three forms of cultural capital and lifestyle health behaviours. STUDY DESIGN: This is a systematic literature review following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Quality appraisal was carried out using the Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies (QAT-OCCSS). METHODS: The review included searches of 13 electronic databases with no restriction on the year of publication. Data were extracted using inclusion criteria and analysed using a narrative format. Eighteen studies were eligible for inclusion. RESULTS: The relationship between cultural capital and lifestyle behaviours was confirmed in the studies measuring institutionalised cultural capital, and mostly supported in the studies that measured objectified and embodied cultural capital. While cultural capital had a significant relationship with some lifestyle behaviours, it was not significantly related to others. The important methodological weaknesses in the literature preclude the ability to state the associations as unequivocal. CONCLUSION: While the association between cultural capital and lifestyle behaviours was supported in most of the included studies, more rigorous research methods are required to effectively assess the causality between cultural capital and lifestyle behaviours. More precise findings may lead to new entry points for the development of interventions to promote healthy lifestyle behaviours.


Asunto(s)
Cultura , Conductas Relacionadas con la Salud , Estilo de Vida , Capital Social , Adolescente , Adulto , Niño , Preescolar , Humanos , Adulto Joven
14.
Wilderness Environ Med ; 28(4): 307-312, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28882617

RESUMEN

OBJECTIVE: Wilderness expeditions inevitably involve risk to participants. Understanding of expedition-related illnesses and injuries allows institutions and individuals to develop strategies to mitigate risk. We describe findings and trends in soft tissue injuries, the second-most common type of injury, among participants in the National Outdoor Leadership School expeditions from 1984 to 2012. METHODS: Injuries and illnesses sustained by students and staff have been recorded continuously since 1984 in the extensive National Outdoor Leadership School database. We performed a retrospective analysis of incidence of soft tissue injuries in this population. Data before 1996 were standardized in order to make use of the entire dataset. RESULTS: Of 9734 total reported incidents, 2151 (22%) were soft tissue related, 707 (33%) of which required evacuation. The sex distribution of incidents was similar to the sex distribution of participants. The largest incidence of soft tissue injuries occurred independent of activity (711 incidents, 33%). The most commonly associated activities were hiking (528 incidents, 25%), camping (301 incidents, 14%), and cooking (205 incidents, 10%). Over the study period, rates of injury declined overall and in every individual category except cooking. CONCLUSIONS: Over this 28-year period, the incidence of soft tissue injuries associated with the most common activities decreased. Incidence of activity-independent injuries did not change significantly, but reported severity decreased. These data provide unique insights to help improve wilderness risk management for institutions and individuals and suggest areas in which educational efforts may further reduce risk.


Asunto(s)
Expediciones/estadística & datos numéricos , Piel/lesiones , Traumatismos de los Tejidos Blandos/epidemiología , Adolescente , Adulto , Anciano , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Estados Unidos/epidemiología , Vida Silvestre , Wyoming/epidemiología , Adulto Joven
15.
Med J Malaysia ; 72(2): 133-134, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28473681

RESUMEN

This case report discusses dumping syndrome in the postbariatric mother. Diagnostically a challenge, the symptoms of postprandial hypoglycaemia mimic common early gestation complaints and may go undiagnosed, thus requiring a high index of suspicion. As weight-loss surgery gains traction, it is pertinent to note at booking and followups. The pregnancy is at-risk and multidisciplinary team management is central. The mainstay of management remains diet modification. There have been case reports of successful medical treatment of dumping syndrome in pregnancy with good maternal and fetal outcomes. However, more data is needed regarding the usage of these medical treatments in pregnancy.


Asunto(s)
Cirugía Bariátrica/efectos adversos , Síndrome de Vaciamiento Rápido/complicaciones , Complicaciones del Embarazo/etiología , Adulto , Cesárea , Síndrome de Vaciamiento Rápido/etiología , Femenino , Humanos , Embarazo
16.
Neuroimage ; 133: 129-143, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-26975556

RESUMEN

The current dogma to explain the extent of injury-related changes following rodent controlled cortical impact (CCI) injury is a focal injury with limited axonal pathology. However, there is in fact good, published histologic evidence to suggest that axonal injury is far more widespread in this model than generally thought. One possibility that might help to explain this is the often-used region-of-interest data analysis approach taken by experimental traumatic brain injury (TBI) diffusion tensor imaging (DTI) or histologic studies that might miss more widespread damage, when compared to the whole brain, statistically robust method of tract-based analysis used more routinely in clinical research. To determine the extent of DTI changes in this model, we acquired in vivo DTI data before and at 1 and 4weeks after CCI injury in 17 adult male rats and analyzed parametric maps of fractional anisotropy (FA), axial, radial, and mean diffusivity (AD, RD, MD), tensor mode (MO), and fiber tract density (FTD) using tract-based spatial statistics. Contusion volume was used as a surrogate marker of injury severity and as a covariate for investigating severity dependence of the data. Mean fiber tract length was also computed from seeds in the cortical spinal tract regions. In parallel experiments (n=3-5/group), we investigated corpus callosum neurofilaments and demyelination using immunohistochemistry (IHC) at 3days and 6weeks, callosal tract patency using dual-label retrograde tract tracing at 5weeks, and the contribution of gliosis to DTI parameter maps using GFAP IHC at 4weeks post-injury. The data show widespread ipsilateral regions of significantly reduced FA at 1week post-injury, driven by temporally changing values of AD, RD, and MD that persist to 4weeks. Demyelination, retrograde label tract loss, and reductions in MO (tract degeneration) and FTD were shown to underpin these data. Significant FA increases occurred in subcortical and corticospinal tract regions that were spatially distinct from regions of FA decrease, grossly affected gliotic areas, and MO changes. However, there was good spatial correspondence between regions of increased FA and areas of increased FTD and mean fiber length. We discuss these widespread changes in DTI parameters in terms of axonal degeneration and potential reorganization, with reference to a resting state fMRI companion paper (Harris et al., 2016, Exp. Neurol. 227:124-138) that demonstrated altered functional connectivity data acquired from the same rats used in this study.


Asunto(s)
Lesiones Traumáticas del Encéfalo/diagnóstico por imagen , Lesiones Traumáticas del Encéfalo/patología , Conectoma/métodos , Lesión Axonal Difusa/diagnóstico por imagen , Lesión Axonal Difusa/etiología , Lesión Axonal Difusa/patología , Imagen de Difusión Tensora/métodos , Interpretación de Imagen Asistida por Computador/métodos , Animales , Anisotropía , Lesiones Traumáticas del Encéfalo/complicaciones , Masculino , Ratas , Ratas Sprague-Dawley , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
17.
Parasite Immunol ; 38(1): 5-11, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26345715

RESUMEN

Throughout evolution, both helminths and bacteria have inhabited our intestines. As intestinal helminths and bacteria inhabit the same environmental niche, it is likely that these organisms interact with, and impact on, each other. In addition, intestinal helminths are well known to alter intestinal physiology, permeability, mucous secretion and the production of antimicrobial peptides - all of which may impact on bacterial survival and spatial organization. Yet despite rapid advances in our understanding of host-intestinal bacteria interactions, the impact of helminths on this relationship has remained largely unexplored. Moreover, although intestinal helminths are generally accepted to possess potent immuno-modulatory activity, it is unknown whether this capacity requires interactions with intestinal bacteria. We propose that this 'ménage à trois' situation is likely to have exerted a strong selective pressure on the development of our metabolic and immune systems. Whilst such pressures remain in developing countries, the eradication of helminths in industrialized countries has shifted this evolutionary balance, possibly underlying the increased development of chronic inflammatory diseases. Thus, helminth-bacteria interactions may represent a key determinant of healthy homoeostasis.


Asunto(s)
Bacterias/inmunología , Microbioma Gastrointestinal/inmunología , Helmintos/inmunología , Interacciones Huésped-Parásitos/inmunología , Intestinos/microbiología , Intestinos/parasitología , Animales , Fenómenos Fisiológicos Bacterianos , Microbioma Gastrointestinal/fisiología , Helmintos/fisiología , Humanos
18.
Int J Sports Med ; 36(8): 609-14, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25837245

RESUMEN

In this study, we quantified the changes in post-exercise resting heart rate (HRrst) associated with acute mountain sickness (AMS), and compared the effects of hypobaric hypoxia (HH) and normobaric hypoxia (NH) on HRrst. We also examined the modulating roles of exercise duration and exposure time on HRrst. Each subject participated in 2 of 6 conditions: normobaric normoxia (NN), NH, or HH (4 400 m altitude equivalent) combined with either 10 or 60 min of moderate cycling at the beginning of an 8-h exposure. AMS was associated with a 2 bpm higher HRrst than when not sick, after taking into account the ambient environment, exercise duration, and SpO2. In addition, HRrst was elevated in both NH and HH compared to NN with HRrst being 50% higher in HH than in NH. Participating in long duration exercise led to elevated resting HRs (0.8-1.4 bpm higher) compared with short exercise, while short exercise caused a progressive increase in HRrst over the exposure period in both NH and HH (0.77-1.2 bpm/h of exposure). This data suggests that AMS, NH, HH, exercise duration, time of exposure, and SpO2 have independent effects on HRrst. It further suggests that hypobaria exerts its own effect on HRrst in hypoxia. Thus NH and HH may not be interchangeable environments.


Asunto(s)
Mal de Altura/fisiopatología , Presión Atmosférica , Ejercicio Físico/fisiología , Frecuencia Cardíaca/fisiología , Hipoxia/fisiopatología , Adulto , Femenino , Humanos , Hipoxia/etiología , Masculino , Método Simple Ciego , Factores de Tiempo
19.
J Emerg Med ; 59(5): 705-709, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32828602

Asunto(s)
Medicaid , Humanos
20.
Wilderness Environ Med ; 26(3): 319-26, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25864086

RESUMEN

OBJECTIVE: To investigate whether ultrasonography can be used for field volume status assessment and to determine whether a detectable difference in intravascular volume exists in individuals with acute mountain sickness (AMS) compared with those without. METHODS: Study was performed at the Himalayan Rescue Association Clinic in Manang, Nepal, located on the Annapurna trekking circuit at an altitude of 3519 m (11545 feet). A convenience sample was taken from individuals trekking over 5 to 8 days from 760 m (2490 feet) to 3519 m (11,545 feet), comparing asymptomatic trekkers vs those who experienced AMS. Subjects were evaluated for AMS based on the Lake Louise AMS Questionnaire (LLS ≥ 3 indicates AMS). After medical screening examination, both groups (control, n = 51; AMS, n = 18) underwent ultrasonography to obtain measurements of inferior vena cava collapsibility index (IVC CI) and left ventricular outflow tract velocity-time integral (LVOT VTI) before and after a passive leg raise (PLR) maneuver. RESULTS: There was no statistically significant difference between groups regarding change in heart rate before and after PLR, or IVC CI; however, there was a statistically significant greater increase in LVOT VTI after PLR maneuver in control group subjects compared with those with AMS (18.96% control vs 11.71% AMS; P < .01). CONCLUSIONS: Ultrasonography is a useful tool in the assessment of intravascular volume at altitude. In this sample, we found ultrasonographic evidence that subjects with AMS have a higher intravascular volume than asymptomatic individuals. These data support the hypothesis that individuals with AMS have decreased altitude-related diuresis compared with asymptomatic individuals.


Asunto(s)
Mal de Altura/diagnóstico por imagen , Montañismo , Enfermedad Aguda , Adulto , Mal de Altura/etiología , Mal de Altura/fisiopatología , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Nepal , Adulto Joven
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