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1.
Nature ; 617(7960): 351-359, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37076628

RESUMEN

Motor cortex (M1) has been thought to form a continuous somatotopic homunculus extending down the precentral gyrus from foot to face representations1,2, despite evidence for concentric functional zones3 and maps of complex actions4. Here, using precision functional magnetic resonance imaging (fMRI) methods, we find that the classic homunculus is interrupted by regions with distinct connectivity, structure and function, alternating with effector-specific (foot, hand and mouth) areas. These inter-effector regions exhibit decreased cortical thickness and strong functional connectivity to each other, as well as to the cingulo-opercular network (CON), critical for action5 and physiological control6, arousal7, errors8 and pain9. This interdigitation of action control-linked and motor effector regions was verified in the three largest fMRI datasets. Macaque and pediatric (newborn, infant and child) precision fMRI suggested cross-species homologues and developmental precursors of the inter-effector system. A battery of motor and action fMRI tasks documented concentric effector somatotopies, separated by the CON-linked inter-effector regions. The inter-effectors lacked movement specificity and co-activated during action planning (coordination of hands and feet) and axial body movement (such as of the abdomen or eyebrows). These results, together with previous studies demonstrating stimulation-evoked complex actions4 and connectivity to internal organs10 such as the adrenal medulla, suggest that M1 is punctuated by a system for whole-body action planning, the somato-cognitive action network (SCAN). In M1, two parallel systems intertwine, forming an integrate-isolate pattern: effector-specific regions (foot, hand and mouth) for isolating fine motor control and the SCAN for integrating goals, physiology and body movement.


Asunto(s)
Mapeo Encefálico , Cognición , Corteza Motora , Mapeo Encefálico/métodos , Mano/fisiología , Imagen por Resonancia Magnética , Corteza Motora/anatomía & histología , Corteza Motora/fisiología , Humanos , Recién Nacido , Lactante , Niño , Animales , Macaca/anatomía & histología , Macaca/fisiología , Pie/fisiología , Boca/fisiología , Conjuntos de Datos como Asunto
2.
Vascular ; : 17085381241247881, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38630458

RESUMEN

OBJECTIVES: Coronary artery disease (CAD) and abdominal aortic aneurysm (AAA) are common arterial pathologies that might occur simultaneously; however, there is not enough evidence about the optimal strategy for patients with concomitant indications of coronary artery bypass grafting (CABG) and open repair of the AAA (AAOR). This study aims to present the outcomes in low and moderate cardiac surgical risk patients who underwent one-stage or two-stage elective CABG and AAOR in a middle-income country. METHODS: An observational, retrospective case series study was conducted. Patients who had low and moderate cardiac surgical risk (less than 8% mortality risk on the STS score) and had the concomitant indication for CABG and AAOR between December 2005 and August 2021 were included. Patients were assigned to one of three strategies: Group 1 underwent one-stage surgery for CABG and AAOR, Group 2 underwent two-stage surgery within the same in-patient stay, and Group 3 underwent two-stage surgery in a new in-patient stay within 6 months. RESULTS: Twenty seven, patients with simultaneous requirements of CABG and AAOR were identified, with a mean age of 69.5 ± 6.1 years and 92.6% were male. The most common comorbidities were hypertension at 77.8% and dyslipidemia at 55.6%. The average mortality risk calculated by the STS score was 2.09% ± 1.53%. In Group 1 (n = 9), 1/9 had in-hospital mortality and no reinterventions were needed. In Group 2 (n = 10), 1/10 had in-hospital mortality, and the most common postoperative complication was acute kidney injury 2/10. Furthermore, 2/10 required a reintervention. In Group 3 (n = 8), no in-hospital mortality was present, however, complications such as sepsis, atrial fibrillation, and acute kidney injury occurred in 2/8 patients each, and 2/8 required a reintervention. CONCLUSION: Patients with CAD and AAA that need a concomitant surgical correction with CABG and an AAOR are uncommon in contemporary practice, given the advances in endovascular therapy. When indicated, one-stage surgery can be performed in patients with low cardiac surgical risk, proper patient selection plays a fundamental role and might be performed in experienced centers. However, two-staged surgeries at the same or different inpatient stay may be considered for asymptomatic AAA with close monitoring during the postoperative period. These findings can hold significance for addressing sociodemographic barriers in low and middle-income countries. More robust and extensive studies are needed to make clear comparisons between the different strategies.

3.
Br J Anaesth ; 131(6): 1030-1042, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37714750

RESUMEN

BACKGROUND: Clinical studies suggest that anaesthesia exposure early in life affects neurobehavioural development. We designed a non-human primate (NHP) study to evaluate cognitive, behavioural, and brain functional and structural alterations after isoflurane exposure during infancy. These NHPs displayed decreased close social behaviour and increased astrogliosis in specific brain regions, most notably in the amygdala. Here we hypothesise that resting-state functional connectivity MRI can detect alterations in connectivity of brain areas that relate to these social behaviours and astrogliosis. METHODS: Imaging was performed in 2-yr-old NHPs under light anaesthesia, after early-in-life (postnatal days 6-12) exposure to 5 h of isoflurane either one or three times, or to room air. Brain images were segmented into 82 regions of interest; the amygdala and the posterior cingulate cortex were chosen for a seed-based resting-state functional connectivity MRI analysis. RESULTS: We found differences between groups in resting-state functional connectivity of the amygdala and the auditory cortices, medial premotor cortex, and posterior cingulate cortex. There were also alterations in resting-state functional connectivity between the posterior cingulate cortex and secondary auditory, polar prefrontal, and temporal cortices, and the anterior insula. Relationships were identified between resting-state functional connectivity alterations and the decrease in close social behaviour and increased astrogliosis. CONCLUSIONS: Early-in-life anaesthesia exposure in NHPs is associated with resting-state functional connectivity alterations of the amygdala and the posterior cingulate cortex with other brain regions, evident at the juvenile age of 2 yr. These changes in resting-state functional connectivity correlate with the decrease in close social behaviour and increased astrogliosis. Using resting-state functional connectivity MRI to study the neuronal underpinnings of early-in-life anaesthesia-induced behavioural alterations could facilitate development of a biomarker for anaesthesia-induced developmental neurotoxicity.


Asunto(s)
Isoflurano , Animales , Isoflurano/efectos adversos , Gliosis , Encéfalo/diagnóstico por imagen , Giro del Cíngulo/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Primates , Mapeo Encefálico/métodos , Vías Nerviosas/diagnóstico por imagen , Vías Nerviosas/fisiología
4.
Trop Anim Health Prod ; 55(3): 185, 2023 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-37130925

RESUMEN

Analyses of the genetic diversity of indigenous cattle are essential for implementing conservation programs, promoting their sustainable use and maintaining productive advantages offered by these breeds in local conditions. The aim of this study was to investigate the genetic diversity and population structure of six Colombian cattle breeds: Blanco Orejinegro (BON), Costeño con Cuernos (CCC), Romosinuano (ROM), Sanmartinero (SAM), Casanareño (CAS), and Hartón del Valle (HDV). Two additional breed groups were included for comparison: Zebu (CEB) and a crossbreed of Colombian cattle breeds × Zebu. Genetic diversity within breeds was analyzed using expected heterozygosity (He), inbreeding coefficient (f), and runs of homozygosity (ROH). Population structure was assessed using model-based clustering (ADMIXTURE) and principal components analysis (PCA). Zebu cattle showed the lowest genetic diversity (He = 0.240). Breeds with the highest genetic diversity level were HDV and BON (He = 0.350 and 0.340, respectively). Inbreeding was lower for Colombian cattle breeds ranging between 0.005 and 0.045. Overall, the largest average genetic distance was found among the group of Colombian cattle breeds and Zebu, while the smallest was found between ROM and CCC. Model-based clustering revealed some level of admixture among HDV and CAS cattle which is consistent with their recent history. The results of the present study provide a useful insight on the genetic structure of Colombian cattle breeds.


Asunto(s)
Genoma , Endogamia , Bovinos/genética , Animales , Colombia , Genómica , Hibridación Genética , Polimorfismo de Nucleótido Simple , Variación Genética
5.
Cereb Cortex ; 31(5): 2450-2465, 2021 03 31.
Artículo en Inglés | MEDLINE | ID: mdl-33350445

RESUMEN

Accumulating evidence shows that auditory cortex (AC) of humans, and other primates, is involved in more complex cognitive processes than feature segregation only, which are shaped by experience-dependent plasticity and thus likely show substantial individual variability. However, thus far, individual variability of ACs has been considered a methodological impediment rather than a phenomenon of theoretical importance. Here, we examined the variability of ACs using intrinsic functional connectivity patterns in humans and macaques. Our results demonstrate that in humans, interindividual variability is greater near the nonprimary than primary ACs, indicating that variability dramatically increases across the processing hierarchy. ACs are also more variable than comparable visual areas and show higher variability in the left than in the right hemisphere, which may be related to the left lateralization of auditory-related functions such as language. Intriguingly, remarkably similar modality differences and lateralization of variability were also observed in macaques. These connectivity-based findings are consistent with a confirmatory task-based functional magnetic resonance imaging analysis. The quantification of variability in auditory function, and the similar findings in both humans and macaques, will have strong implications for understanding the evolution of advanced auditory functions in humans.


Asunto(s)
Corteza Auditiva/diagnóstico por imagen , Vías Auditivas/diagnóstico por imagen , Variación Biológica Individual , Adulto , Animales , Corteza Auditiva/fisiología , Vías Auditivas/fisiología , Femenino , Neuroimagen Funcional , Humanos , Macaca mulatta , Imagen por Resonancia Magnética , Masculino , Adulto Joven
6.
Cereb Cortex ; 30(3): 1573-1585, 2020 03 14.
Artículo en Inglés | MEDLINE | ID: mdl-31665252

RESUMEN

Human and animal cross-sectional studies have shown that maternal levels of the inflammatory cytokine interleukin-6 (IL-6) may compromise brain phenotypes assessed at single time points. However, how maternal IL-6 associates with the trajectory of brain development remains unclear. We investigated whether maternal IL-6 levels during pregnancy relate to offspring amygdala volume development and anxiety-like behavior in Japanese macaques. Magnetic resonance imaging (MRI) was administered to 39 Japanese macaque offspring (Female: 18), providing at least one or more time points at 4, 11, 21, and 36 months of age with a behavioral assessment at 11 months of age. Increased maternal third trimester plasma IL-6 levels were associated with offspring's smaller left amygdala volume at 4 months, but with more rapid amygdala growth from 4 to 36 months. Maternal IL-6 predicted offspring anxiety-like behavior at 11 months, which was mediated by reduced amygdala volumes in the model's intercept (i.e., 4 months). The results increase our understanding of the role of maternal inflammation in the development of neurobehavioral disorders by detailing the associations of a commonly examined inflammatory indicator, IL-6, on amygdala volume growth over time, and anxiety-like behavior.


Asunto(s)
Amígdala del Cerebelo/patología , Conducta Animal/fisiología , Interleucina-6/sangre , Efectos Tardíos de la Exposición Prenatal/patología , Amígdala del Cerebelo/metabolismo , Animales , Encéfalo/metabolismo , Encéfalo/patología , Niño , Depresión/metabolismo , Depresión/fisiopatología , Femenino , Humanos , Macaca fuscata , Conducta Materna/fisiología , Embarazo , Efectos Tardíos de la Exposición Prenatal/metabolismo
7.
Proc Natl Acad Sci U S A ; 115(40): 9851-9858, 2018 10 02.
Artículo en Inglés | MEDLINE | ID: mdl-30275319

RESUMEN

Attention deficit hyperactivity disorder (ADHD) is now among the most commonly diagnosed chronic psychological dysfunctions of childhood. By varying estimates, it has increased by 30% in the past 20 years. Environmental factors that might explain this increase have been explored. One such factor may be audiovisual media exposure during early childhood. Observational studies in humans have linked exposure to fast-paced television in the first 3 years of life with subsequent attentional deficits in later childhood. Although longitudinal and well controlled, the observational nature of these studies precludes definitive conclusions regarding a causal relationship. As experimental studies in humans are neither ethical nor practical, mouse models of excessive sensory stimulation (ESS) during childhood, akin to the enrichment studies that have previously shown benefits of stimulation in rodents, have been developed. Experimental studies using this model have corroborated that ESS leads to cognitive and behavioral deficits, some of which may be potentially detrimental. Given the ubiquity of media during childhood, these findings in humansand rodents perhaps have important implications for public health.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad , Exposición a Riesgos Ambientales/efectos adversos , Animales , Trastorno por Déficit de Atención con Hiperactividad/etiología , Trastorno por Déficit de Atención con Hiperactividad/patología , Trastorno por Déficit de Atención con Hiperactividad/fisiopatología , Niño , Preescolar , Modelos Animales de Enfermedad , Humanos , Lactante , Ratones
8.
Int J Mol Sci ; 22(15)2021 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-34360853

RESUMEN

Long QT syndromes can be either acquired or congenital. Drugs are one of the many etiologies that may induce acquired long QT syndrome. In fact, many drugs frequently used in the clinical setting are a known risk factor for a prolonged QT interval, thus increasing the chances of developing torsade de pointes. The molecular mechanisms involved in the prolongation of the QT interval are common to most medications. However, there is considerable inter-individual variability in drug response, thus making the application of personalized medicine a relevant aspect in long QT syndrome, in order to evaluate the risk of every individual from a pharmacogenetic standpoint.


Asunto(s)
Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Síndrome de QT Prolongado/inducido químicamente , Torsades de Pointes/inducido químicamente , Humanos , Preparaciones Farmacéuticas , Factores de Riesgo
9.
Sens Actuators A Phys ; 288: 79-85, 2019 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-31777429

RESUMEN

The word "haptics" refers to technologies designed to stimulate the tactile and kinesthetic senses. Kinesthesia-the sense of motion-is triggered by imposing forces upon the joints, tendons, and muscles to recreate the geometry and stiffness of objects, as may be useful in physical therapy or virtual reality. Here, we introduce a form of kinesthetic feedback by manipulating the mechanical properties of spandex impregnated with a thermoplastic polymer. Heating or cooling this textile-thermoplastic composite just above or below its glass transition temperature (T g) dramatically changes its mechanical properties (corresponding to a decrease in storage modulus from 36 MPa to 0.55 MPa). In the form of a glove, the composite can also be healed after inadvertent overextension in its stiffened state by heating it above its T g. When fitted with thermoelectric devices for active heating and cooling, the flexible or stiffened state of a glove can be perceived by human subjects. As an example of a human-machine interface, the glove is used to control a robotic finger. When the robotic finger makes contact with a wall, a signal is sent to thermoelectric devices in the glove to cool (stiffen the finger) and thus provide kinesthetic feedback to the user.

10.
Nano Lett ; 18(8): 5306-5311, 2018 08 08.
Artículo en Inglés | MEDLINE | ID: mdl-30024767

RESUMEN

Despite the apparent convenience of microfluidic technologies for applications in healthcare, such devices often rely on capital-intensive optics and other peripheral equipment that limit throughput. Here, we monitored the transit of fluids, gases, particles, and cells as they flowed through a microfluidic channel without the use of a camera or laser, i.e., "optics-free" microfluidics. We did this by monitoring the deformation of the side walls caused by the analyte passing through the channel. Critically, the analyte did not have to make contact with the channel walls to induce a deflection. This minute deformation was transduced into a change in electrical resistance using an ultrasensitive piezoresitive film composed of metallic nano-islands on graphene. We related changes in the resistance of the sensor to the theoretical deformation of the channel at varying flow rates. Then, we used air bubbles to induce a perturbation on the elastomeric channel walls and measured the viscoelastic relaxation of the walls of the channel. We obtained a viscoelastic time constant of 11.3 ± 3.5 s-1 for polydimethylsiloxane, which is consistent with values obtained using other techniques. Finally, we flowed silica particles and human mesenchymal stem cells and measured the deformation profiles of the channel. This technique yielded a convenient, continuous, and non-contact measurement of rigid and deformable particles without the use of a laser or camera.


Asunto(s)
Grafito/química , Nanopartículas del Metal/química , Técnicas Analíticas Microfluídicas/instrumentación , Nanocompuestos/química , Dimetilpolisiloxanos/química , Diseño de Equipo/instrumentación , Cinética , Tamaño de la Partícula , Propiedades de Superficie , Viscosidad
11.
Sens Actuators A Phys ; 263: 702-706, 2017 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-28860679

RESUMEN

This article describes the fabrication of single-nanowire strain sensors by thin sectioning of gold films with an ultramicrotome-i.e., "nanoskiving." The nanowire sensors are transferred to various substrates from the water bath on which they float after sectioning. The electrical response of these single nanowires to mechanical strain is investigated, with the lowest detectable strain determined to be 1.6 × 10-5 with a repeatable response to strains as high as 7 × 10-4. The sensors are shown to have an enhanced sensitivity with a gauge factor of 3.1 on average, but as high as 9.5 in the low strain regime (ε ~ 1 × 10-5). Conventional thin films of gold of the same height as the nanowires are used as controls, and are unable to detect those same strains. The practicality of this sensor is investigated by transferring a single nanowire to polyimide tape, and placing the sensor on the wrist to monitor the pulse pressure waveform from the radial artery. The nanowires are fabricated with simple tools and require no lithography. Moreover, the sensors can be "manufactured" efficiently, as each consecutive section of the film is a quasi copy of the previous nanowire. The simple fabrication of these nanowires, along with the compatibility with flexible substrates, offers possibilities in developing new kinds of devices for biomedical applications and structural health monitoring.

12.
Anal Chem ; 87(1): 394-8, 2015 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-25496376

RESUMEN

We present a proof-of-concept demonstration of an all-printed temporary tattoo-based glucose sensor for noninvasive glycemic monitoring. The sensor represents the first example of an easy-to-wear flexible tattoo-based epidermal diagnostic device combining reverse iontophoretic extraction of interstitial glucose and an enzyme-based amperometric biosensor. In-vitro studies reveal the tattoo sensor's linear response toward physiologically relevant glucose levels with negligible interferences from common coexisting electroactive species. The iontophoretic-biosensing tattoo platform is reduced to practice by applying the device on human subjects and monitoring variations in glycemic levels due to food consumption. Correlation of the sensor response with that of a commercial glucose meter underscores the promise of the tattoo sensor to detect glucose levels in a noninvasive fashion. Control on-body experiments demonstrate the importance of the reverse iontophoresis operation and validate the sensor specificity. This preliminary investigation indicates that the tattoo-based iontophoresis-sensor platform holds considerable promise for efficient diabetes management and can be extended toward noninvasive monitoring of other physiologically relevant analytes present in the interstitial fluid.


Asunto(s)
Técnicas Biosensibles/instrumentación , Epidermis/química , Líquido Extracelular/química , Glucosa/análisis , Iontoforesis/instrumentación , Tatuaje/métodos , Adulto , Diseño de Equipo , Femenino , Voluntarios Sanos , Humanos , Masculino , Adulto Joven
13.
Analyst ; 139(7): 1632-6, 2014 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-24496180

RESUMEN

The present work describes the first example of a wearable salivary metabolite biosensor based on the integration of a printable enzymatic electrode on a mouthguard. The new mouthguard enzymatic biosensor, based on an immobilized lactate oxidase and a low potential detection of the peroxide product, exhibits high sensitivity, selectivity and stability using whole human saliva samples. Such non-invasive mouthguard metabolite biosensors could tender useful real-time information regarding a wearer's health, performance and stress level, and thus hold considerable promise for diverse biomedical and fitness applications.


Asunto(s)
Técnicas Biosensibles/métodos , Ácido Láctico/análisis , Saliva/metabolismo , Biomarcadores/análisis , Técnicas Biosensibles/instrumentación , Humanos , Monitoreo Fisiológico , Saliva/química , Saliva/enzimología , Factores de Tiempo
14.
Sci Rep ; 14(1): 1230, 2024 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-38216695

RESUMEN

This study combines volcanic gas compositions, SO2 flux and satellite thermal data collected at Nevado del Ruiz between 2018 and 2021. We find the Nevado del Ruiz plume to have exhibited relatively steady, high CO2 compositions (avg. CO2/ST ratios of 5.4 ± 1.9) throughout. Our degassing models support that the CO2/ST ratio variability derives from volatile exsolution from andesitic magma stored in the 1-4 km depth range. Separate ascent of CO2-rich gas bubbles through shallow (< 1 km depth), viscous, conduit resident magma causes the observed excess degassing. We infer that degassing of ~ 974 mm3 of shallow (1-4 km) stored magma has sourced the elevated SO2 degassing recorded during 2018-2021 (average flux ~ 1548 t/d). Of this, only < 1 mm3 of magma have been erupted through dome extrusion, highlighting a large imbalance between erupted and degassed magma. Escalating deep CO2 gas flushing, combined with the disruption of passive degassing, through sudden accumulation and pressurization of bubbles due to lithostatic pressure, may accelerate volcanic unrest and eventually lead to a major eruption.

15.
JMIR Cancer ; 10: e47359, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38416544

RESUMEN

BACKGROUND: Frequent sensor-assisted monitoring of changes in swallowing function may help improve detection of radiation-associated dysphagia before it becomes permanent. While our group has prototyped an epidermal strain/surface electromyography sensor that can detect minute changes in swallowing muscle movement, it is unknown whether patients with head and neck cancer would be willing to wear such a device at home after radiation for several months. OBJECTIVE: We iteratively assessed patients' design preferences and perceived barriers to long-term use of the prototype sensor. METHODS: In study 1 (questionnaire only), survivors of pharyngeal cancer who were 3-5 years post treatment and part of a larger prospective study were asked their design preferences for a hypothetical throat sensor and rated their willingness to use the sensor at home during the first year after radiation. In studies 2 and 3 (iterative user testing), patients with and survivors of head and neck cancer attending visits at MD Anderson's Head and Neck Cancer Center were recruited for two rounds of on-throat testing with prototype sensors while completing a series of swallowing tasks. Afterward, participants were asked about their willingness to use the sensor during the first year post radiation. In study 2, patients also rated the sensor's ease of use and comfort, whereas in study 3, preferences were elicited regarding haptic feedback. RESULTS: The majority of respondents in study 1 (116/138, 84%) were willing to wear the sensor 9 months after radiation, and participant willingness rates were similar in studies 2 (10/14, 71.4%) and 3 (12/14, 85.7%). The most prevalent reasons for participants' unwillingness to wear the sensor were 9 months being excessive, unwanted increase in responsibility, and feeling self-conscious. Across all three studies, the sensor's ability to detect developing dysphagia increased willingness the most compared to its appearance and ability to increase adherence to preventive speech pathology exercises. Direct haptic signaling was also rated highly, especially to indicate correct sensor placement and swallowing exercise performance. CONCLUSIONS: Patients and survivors were receptive to the idea of wearing a personalized risk sensor for an extended period during the first year after radiation, although this may have been limited to well-educated non-Hispanic participants. A significant minority of patients expressed concern with various aspects of the sensor's burden and its appearance. TRIAL REGISTRATION: ClinicalTrials.gov NCT03010150; https://clinicaltrials.gov/study/NCT03010150.

16.
Anal Chem ; 85(14): 6553-60, 2013 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-23815621

RESUMEN

The present work describes the first example of real-time noninvasive lactate sensing in human perspiration during exercise events using a flexible printed temporary-transfer tattoo electrochemical biosensor that conforms to the wearer's skin. The new skin-worn enzymatic biosensor exhibits chemical selectivity toward lactate with linearity up to 20 mM and demonstrates resiliency against continuous mechanical deformation expected from epidermal wear. The device was applied successfully to human subjects for real-time continuous monitoring of sweat lactate dynamics during prolonged cycling exercise. The resulting temporal lactate profiles reflect changes in the production of sweat lactate upon varying the exercise intensity. Such skin-worn metabolite biosensors could lead to useful insights into physical performance and overall physiological status, hence offering considerable promise for diverse sport, military, and biomedical applications.


Asunto(s)
Técnicas Biosensibles/métodos , Sistemas de Computación , Técnicas Electroquímicas/métodos , Ácido Láctico/análisis , Sudor/química , Tatuaje/métodos , Adulto , Técnicas Biosensibles/instrumentación , Técnicas Electroquímicas/instrumentación , Epidermis/química , Epidermis/metabolismo , Femenino , Humanos , Masculino , Sudoración/fisiología , Adulto Joven
17.
Analyst ; 138(18): 5288-95, 2013 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-23865089

RESUMEN

Increasing security needs require field-deployable, on-the-spot detection tools for the rapid and reliable identification of gunshot residue (GSR) and nitroaromatic explosive compounds. This manuscript presents a simple, all-solid-state, wearable fingertip sensor for the rapid on-site voltammetric screening of GSR and explosive surface residues. To fabricate the new Forensic Fingers, we screen-print a three-electrode setup onto a nitrile finger cot, and coat another finger cot with an ionogel electrolyte layer. The new integrated sampling/detection methodology relies on 'voltammetry of microparticles' (VMP) and involves an initial mechanical transfer of trace amounts of surface-confined analytes directly onto the fingertip-based electrode contingent. Voltammetric measurements of the sample residues are carried out upon bringing the working electrode (printed on the index finger cot) in direct contact with a second finger cot coated with an ionogel electrolyte (worn on the thumb), thus completing the solid-state electrochemical cell. Sampling and screening are performed in less than four minutes and generate distinct voltammetric fingerprints which are specific to both GSR and explosives. The use of the solid, flexible ionogel electrolyte eliminates any liquid handling which can resolve problems associated with leakage, portability and contamination. A detailed study reveals that the fingertip detection system can rapidly identify residues of GSR and nitroaromatic compounds with high specificity, without compromising its attractive behavior even after undergoing repeated mechanical stress. This new integrated sampling/detection fingertip strategy holds considerable promise as a rapid, effective and low-cost approach for on-site crime scene investigations in various forensic scenarios.


Asunto(s)
Sustancias Explosivas/análisis , Dedos , Armas de Fuego , Ciencias Forenses/instrumentación , Dinitrobencenos/análisis , Electroquímica , Electrodos , Humanos
18.
Analyst ; 138(1): 123-8, 2013 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-23113321

RESUMEN

This article presents the fabrication and characterization of novel tattoo-based solid-contact ion-selective electrodes (ISEs) for non-invasive potentiometric monitoring of epidermal pH levels. The new fabrication approach combines commercially available temporary transfer tattoo paper with conventional screen printing and solid-contact polymer ISE methodologies. The resulting tattoo-based potentiometric sensors exhibit rapid and sensitive response to a wide range of pH changes with no carry-over effects. Furthermore, the tattoo ISE sensors endure repetitive mechanical deformation, which is a key requirement of wearable and epidermal sensors. The flexible and conformal nature of the tattoo sensors enable them to be mounted on nearly any exposed skin surface for real-time pH monitoring of the human perspiration, as illustrated from the response during a strenuous physical activity. The resulting tattoo-based ISE sensors offer considerable promise as wearable potentiometric sensors suitable for diverse applications.


Asunto(s)
Epidermis/química , Potenciometría/instrumentación , Adulto , Electrodos , Humanos , Concentración de Iones de Hidrógeno , Masculino , Papel , Tatuaje
19.
Sci Rep ; 12(1): 15220, 2022 09 08.
Artículo en Inglés | MEDLINE | ID: mdl-36076053

RESUMEN

Nutrition during the first years of life has a significant impact on brain development. This study characterized differences in brain maturation from birth to 6 months of life in infant macaques fed formulas differing in content of lutein, ß-carotene, and other carotenoids using Magnetic Resonance Imaging to measure functional connectivity. We observed differences in functional connectivity based on the interaction of diet, age and brain networks. Post hoc analysis revealed significant diet-specific differences between insular-opercular and somatomotor networks at 2 months of age, dorsal attention and somatomotor at 4 months of age, and within somatomotor and between somatomotor-visual and auditory-dorsal attention networks at 6 months of age. Overall, we found a larger divergence in connectivity from the breastfeeding group in infant macaques fed formula containing no supplemental carotenoids in comparison to those fed formula supplemented with carotenoids. These findings suggest that carotenoid formula supplementation influences functional brain development.


Asunto(s)
Carotenoides , Macaca , Animales , Alimentos Formulados , Humanos , Luteína/farmacología , beta Caroteno
20.
BMJ Open ; 12(11): e063182, 2022 11 30.
Artículo en Inglés | MEDLINE | ID: mdl-36450427

RESUMEN

INTRODUCTION: Death following surgical procedures is a global health problem, accounting for 4.2 million deaths annually within the first 30 postoperative days. The fourth indicator of The Lancet Commission on Global Surgery is essential as it seeks to standardise postoperative mortality. Consequently, it helps identify the strengths and weaknesses of each country's healthcare system. Accurate information on this indicator is not available in Colombia, limiting the possibility of interventions applied to our population. We aim to describe the in-hospital perioperative mortality of the surgical procedures performed in Colombia. The data obtained will help formulate public policies, improving the quality of the surgical departments. METHODS AND ANALYSIS: An observational, analytical, multicentre prospective cohort study will be conducted throughout Colombia. Patients over 18 years of age who have undergone a surgical procedure, excluding radiological/endoscopic procedures, will be included. A sample size of 1353 patients has been projected to achieve significance in our primary objective; however, convenience sampling will be used, as we aim to include all possible patients. Data collection will be carried out prospectively for 1 week. Follow-up will continue until hospital discharge, death or a maximum of 30 inpatient days. The primary outcome is perioperative mortality. A descriptive analysis of the data will be performed, along with a case mix analysis of mortality by procedure-related, patient-related and hospital-related conditions ETHICS AND DISSEMINATION: The Fundación Cardioinfantil-Instituto de Cardiología Ethics Committee approved this study (No. 41-2021). The results are planned to be disseminated in three scenarios: the submission of an article for publication in a high-impact scientific journal and presentations at the Colombian Surgical Forum and the Congress of the American College of Surgeons. TRIAL REGISTRATION NUMBER: NCT05147623.


Asunto(s)
Estudios Prospectivos , Humanos , Adolescente , Adulto , Colombia/epidemiología , Tamaño de la Muestra , Mortalidad Hospitalaria , Resultado del Tratamiento , Estudios Observacionales como Asunto , Estudios Multicéntricos como Asunto
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