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1.
Psychophysiology ; 61(7): e14551, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38516942

RESUMEN

The Predatory Imminence Continuum Theory proposes that defensive behaviors depend on the proximity of a threat. While the neural mechanisms underlying this proposal are well studied in animal models, it remains poorly understood in humans. To address this issue, we recorded EEG from 24 (15 female) young adults engaged in a first-person virtual reality Risk-Reward interaction task. On each trial, participants were placed in a virtual room and presented with either a threat or reward conditioned stimulus (CS) in the same room location (proximal) or different room location (distal). Behaviorally, all participants learned to avoid the threat-CS, with most using the optimal behavior to actively avoid the proximal threat-CS (88% accuracy) and passively avoid the distal threat-CS (69% accuracy). Similarly, participants learned to actively approach the distal reward-CS (82% accuracy) and to remain passive to the proximal reward-CS (72% accuracy). At an electrophysiological level, we observed a general increase in theta power (4-8 Hz) over the right posterior channel P8 across all conditions, with the proximal threat-CS evoking the largest theta response. By contrast, distal cues induced two bursts of gamma (30-60 Hz) power over midline-parietal channel Pz (200 msec post-cue) and right frontal channel Fp2 (300 msec post-cue). Interestingly, the first burst of gamma power was sensitive to the distal threat-CS and the second burst at channel Fp2 was sensitive to the distal reward-CS. Together, these findings demonstrate that oscillatory processes differentiate between the spatial proximity information during threat and reward encoding, likely optimizing the selection of the appropriate behavioral response.


Asunto(s)
Electroencefalografía , Recompensa , Realidad Virtual , Humanos , Femenino , Masculino , Adulto Joven , Adulto , Navegación Espacial/fisiología , Miedo/fisiología , Ritmo Teta/fisiología , Condicionamiento Clásico/fisiología , Adolescente , Ondas Encefálicas/fisiología
2.
Environ Res ; 262(Pt 1): 119776, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39142453

RESUMEN

BACKGROUND: Although human biomonitoring of environmental chemicals has been considered a gold standard, these methods can be costly, burdensome, and prone to unwanted sources of variability that may cause confounding. Silicone wristbands have recently emerged as innovative passive samplers for measuring personal exposures. METHODS: In a pilot study from 2019 to 2021 involving 55 children aged 5-9 years in Seattle and Yakima, Washington, we utilized silicone wristbands to explore associations of sociodemographic variables and COVID-19-related restrictions, including school closures, with exposures to numerous chemicals including brominated and organophosphate ester (OPE) flame retardants, polychlorinated biphenyls, polycyclic aromatic hydrocarbons (PAHs), phthalates, and pesticides. We additionally conducted the first analysis testing silicone wristband chemicals as predictors of child wheeze, individually and in mixtures via logistic weighted quantile sum regression (WQS). RESULTS: Among 109 semi-volatile organic compounds measured, we detected 40 in >60% of wristbands worn by children continuously for an average of 5 days. Chemicals were generally positively correlated, especially within the same class. Male sex and increasing age were linked with higher exposures across several chemical classes; Hispanic/Latino ethnicity was linked with higher exposures to some phthalates and OPEs. COVID-19 restrictions were associated with lower wristband concentrations of brominated and triaryl OPE flame retardants. Each one-decile higher WQS exposure index was suggestively associated with 2.11-fold [95% CI: 0.93-4.80] higher odds of child wheeze. Risk of child wheeze was higher per 10-fold increase in the PAH chrysene (RR = 1.93[1.07-3.49]), the pesticide cis-permethrin (3.31[1.23-8.91]), and di-isononyl phthalate (DINP) (5.40[1.22-24.0]) CONCLUSIONS: Our identification of demographic factors including sex, age, and ethnicity associated with chemical exposures may aid efforts to mitigate exposure disparities. Lower exposures to flame retardants during pandemic restrictions corroborates prior evidence of higher levels of these chemicals in school versus home environments. Future research in larger cohorts is needed to validate these findings.

3.
Environ Res ; 252(Pt 1): 118789, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38555096

RESUMEN

Melamine caused acute nephrotoxicity in a past food adulteration incident, but it is unclear whether and how widespread ambient exposure to melamine and related compounds might affect pediatric kidney health. We assessed cross-sectional associations between childhood exposure to melamine and its derivatives and biomarkers of kidney injury and health and explored potential heterogeneity by sex suggested by sex-dependent differences in renal physiology. We measured melamine and its derivatives ammeline, ammelide, and cyanuric acid (CYA) in spot urine samples collected from 192 children from an urban site (Seattle, WA) and 187 children from a rural site (Yakima, WA) aged 4-8 years in the Global Alliance to Prevent Prematurity and Stillbirth (GAPPS) Study. In addition, biomarkers of kidney injury were measured in the same urine samples, including albumin, total protein, KIM-1, NAG, NGAL, and EGF. We utilized linear regressions to examine associations between individual chemical exposures and kidney biomarkers. Interaction terms examined association modification by sex, as well as potential interactions between melamine and CYA. Despite comparable exposures, girls had higher levels of many kidney injury biomarkers compared to boys. A ten-fold higher melamine concentration was associated with a 18% (95% CI: 5.6%, 31%) higher EGF in the full sample, while ten-fold higher melamine was associated with a 76% (14.1%, 173%) higher KIM-1 in boys but not in girls (-10.1% (-40.6%, 36.1%), interaction p = 0.026). Melamine exhibited significant negative interactions with CYA in association with total protein and NAG that appeared to be specific to girls. Our results suggest possible associations between melamine exposure and markers of kidney injury that may be more pronounced in boys. These findings provide novel insights into melamine and related derivative compound health effects at low levels of exposure in children and emphasize the role of sex in mediating the relationship between nephrotoxicant exposure and kidney injury.


Asunto(s)
Biomarcadores , Exposición a Riesgos Ambientales , Triazinas , Humanos , Triazinas/orina , Triazinas/toxicidad , Femenino , Masculino , Niño , Preescolar , Biomarcadores/orina , Riñón/efectos de los fármacos , Estudios Transversales , Contaminantes Ambientales/orina , Contaminantes Ambientales/toxicidad
4.
Environ Res ; 241: 117632, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-37967704

RESUMEN

BACKGROUND: Ozone (O3) exposure interrupts normal lung development in animal models. Epidemiologic evidence further suggests impairment with higher long-term O3 exposure across early and middle childhood, although study findings to date are mixed and few have investigated vulnerable subgroups. METHODS: Participants from the CANDLE study, a pregnancy cohort in Shelby County, TN, in the ECHO-PATHWAYS Consortium, were included if children were born at gestational age >32 weeks, completed a spirometry exam at age 8-9, and had a valid residential history from birth to age 8. We estimated lifetime average ambient O3 exposure based on each child's residential history from birth to age 8, using a validated fine-resolution spatiotemporal model. Spirometry was performed at the age 8-9 year study visit to assess Forced Expiratory Volume in the first second (FEV1) and Forced Vital Capacity (FVC) as primary outcomes; z-scores were calculated using sex-and-age-specific reference equations. Linear regression with robust variance estimators was used to examine associations between O3 exposure and continuous lung function z-scores, adjusted for child, sociodemographic, and home environmental factors. Potential susceptible subgroups were explored using a product term in the regression model to assess effect modification by child sex, history of bronchiolitis in infancy, and allergic sensitization. RESULTS: In our sample (n = 648), O3 exposure averaged from birth to age 8 was modest (mean 26.6 [SD 1.1] ppb). No adverse associations between long-term postnatal O3 exposure were observed with either FEV1 (ß = 0.12, 95% CI: -0.04, 0.29) or FVC (ß = 0.03, 95% CI: -0.13, 0.19). No effect modification by child sex, history of bronchiolitis in infancy, or allergic sensitization was detected for associations with 8-year average O3. CONCLUSIONS: In this sample with low O3 concentrations, we did not observe adverse associations between O3 exposures averaged from birth to age 8 and lung function in middle childhood.


Asunto(s)
Contaminantes Atmosféricos , Bronquiolitis , Ozono , Femenino , Embarazo , Humanos , Niño , Lactante , Contaminantes Atmosféricos/análisis , Pulmón , Capacidad Vital , Ozono/toxicidad , Ozono/análisis , Volumen Espiratorio Forzado , Exposición a Riesgos Ambientales
5.
Environ Health ; 23(1): 26, 2024 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-38454435

RESUMEN

BACKGROUND AND AIM: Studies suggest prenatal exposure to polycyclic aromatic hydrocarbons (PAHs) may influence wheezing or asthma in preschool-aged children. However, the impact of prenatal PAH exposure on asthma and wheeze in middle childhood remain unclear. We investigated these associations in socio-demographically diverse participants from the ECHO PATHWAYS multi-cohort consortium. METHODS: We included 1,081 birth parent-child dyads across five U.S. cities. Maternal urinary mono-hydroxylated PAH metabolite concentrations (OH-PAH) were measured during mid-pregnancy. Asthma at age 8-9 years and wheezing trajectory across childhood were characterized by caregiver reported asthma diagnosis and asthma/wheeze symptoms. We used logistic and multinomial regression to estimate odds ratios of asthma and childhood wheezing trajectories associated with five individual OH-PAHs, adjusting for urine specific gravity, various maternal and child characteristics, study site, prenatal and postnatal smoke exposure, and birth year and season in single metabolite and mutually adjusted models. We used multiplicative interaction terms to evaluate effect modification by child sex and explored OH-PAH mixture effects through Weighted Quantile Sum regression. RESULTS: The prevalence of asthma in the study population was 10%. We found limited evidence of adverse associations between pregnancy OH-PAH concentrations and asthma or wheezing trajectories. We observed adverse associations between 1/9-hydroxyphenanthrene and asthma and persistent wheeze among girls, and evidence of inverse associations with asthma for 1-hydroxynathpthalene, which was stronger among boys, though tests for effect modification by child sex were not statistically significant. CONCLUSIONS: In a large, multi-site cohort, we did not find strong evidence of an association between prenatal exposure to PAHs and child asthma at age 8-9 years, though some adverse associations were observed among girls.


Asunto(s)
Asma , Fenantrenos , Hidrocarburos Policíclicos Aromáticos , Efectos Tardíos de la Exposición Prenatal , Niño , Embarazo , Masculino , Femenino , Preescolar , Humanos , Estudios Longitudinales , Hidrocarburos Policíclicos Aromáticos/efectos adversos , Efectos Tardíos de la Exposición Prenatal/inducido químicamente , Efectos Tardíos de la Exposición Prenatal/epidemiología , Ruidos Respiratorios , Asma/inducido químicamente , Asma/epidemiología
6.
Am J Obstet Gynecol ; 228(1): 73.e1-73.e18, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-35868418

RESUMEN

BACKGROUND: Spontaneous preterm birth accounts for most preterm births and leads to significant morbidity in the newborn and childhood period. This subtype of preterm birth represents an increasing proportion of all preterm births when compared with medically indicated preterm birth, yet it is understudied in omics analyses. The placenta is a key regulator of fetal and newborn health, and the placental transcriptome can provide insight into pathologic changes that lead to spontaneous preterm birth. OBJECTIVE: This analysis aimed to identify genes for which placental expression was associated with spontaneous preterm birth (including early preterm and late preterm birth). STUDY DESIGN: The ECHO PATHWAYS consortium extracted RNA from placental samples collected from the Conditions Affecting Neurocognitive Development and Learning in Early Childhood and the Global Alliance to Prevent Prematurity and Stillbirth studies. Placental transcriptomic data were obtained by RNA sequencing. Linear models were fit to estimate differences in placental gene expression between term birth and spontaneous preterm birth (including gestational age subgroups defined by the American College of Obstetricians and Gynecologists). Models were adjusted for numerous confounding variables, including labor status, cohort, and RNA sequencing batch. This analysis excluded patients with induced labor, chorioamnionitis, multifetal gestations, or medical indications for preterm birth. Our combined cohort contained gene expression data for 14,023 genes in 48 preterm and 540 term samples. Genes and pathways were considered statistically significantly different at false discovery rate-adjusted P value of <.05. RESULTS: In total, we identified 1728 genes for which placental expression was associated with spontaneous preterm birth with more differences in expression in early preterm samples than late preterm samples when compared with full-term samples. Of those, 9 genes were significantly decreased in both early and late spontaneous preterm birth, and the strongest associations involved placental expression of IL1B, ALPL, and CRLF1. In early and late preterm samples, we observed decreased expression of genes involved in immune signaling, signal transduction, and endocrine function. CONCLUSION: This study provides a comprehensive assessment of the differences in the placental transcriptome associated with spontaneous preterm birth with robust adjustment for confounding. Results of this study are in alignment with the known etiology of spontaneous preterm birth, because we identified multiple genes and pathways for which the placental and chorioamniotic membrane expression was previously associated with prematurity, including IL1B. We identified decreased expression in key signaling pathways that are essential for placental growth and function, which may be related to the etiology of spontaneous preterm birth. We identified increased expression of genes within metabolic pathways associated exclusively with early preterm birth. These signaling and metabolic pathways may provide clinically targetable pathways and biomarkers. The findings presented here can be used to understand underlying pathologic changes in premature placentas, which can inform and improve clinical obstetrics practice.


Asunto(s)
Corioamnionitis , Nacimiento Prematuro , Preescolar , Recién Nacido , Embarazo , Femenino , Humanos , Nacimiento Prematuro/genética , Placenta/patología , Transcriptoma , Recien Nacido Prematuro , Corioamnionitis/genética , Corioamnionitis/patología
7.
Environ Res ; 226: 115630, 2023 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-36889565

RESUMEN

BACKGROUND: Atopic disease may be influenced by prenatal and early life exposure to endocrine disrupting chemicals, including bisphenols, but results from epidemiological studies have been mixed. This study aimed to extend the epidemiological literature, hypothesizing that children with higher prenatal bisphenol exposure are more likely to have childhood atopic disease. METHODS: Urinary bisphenol A (BPA) and S (BPS) concentrations were measured in each trimester from 501 pregnant women in a multi-center, prospective pregnancy cohort. Ever asthma, current asthma, wheeze, and food allergy) were assessed at age six via standardized ISAAC questionnaire. We constructed generalized estimating equations to examine BPA and BPS exposure jointly at each trimester for each atopy phenotype. BPA was modeled as a log-transformed continuous variable, whereas BPS was modeled as detected versus not detected. We also modeled pregnancy-averaged BPA values and a categorical indicator for number of detectable BPS values over pregnancy (0-3) in logistic regression models. RESULTS: First trimester BPA was associated with inverse odds of food allergy among the entire study sample (OR = 0.78, 95% CI = 0.64-0.95, p = 0.01) and females only (OR = 0.69, 95% CI = 0.52-0.90, p = 0.006). The inverse relationship persisted in pregnancy-averaged models of BPA among females (OR = 0.56, 95% CI = 0.35-0.90, p = 0.006). Second trimester BPA was associated with greater odds of food allergy in the entire sample (OR = 1.27, 95% CI = 1.02-1.58, p = 0.03) and among males only (OR = 1.48, 95% CI = 1.02-2.14, p = 0.04). Odds of current asthma increased among males in the pregnancy-averaged BPS models (OR = 1.65, 95% CI = 1.01-2.69, p = 0.045). CONCLUSION: We saw opposite effects of BPA on food allergy that were trimester- and sex-specific. These divergent associations warrant further investigation. There is some evidence to suggest that prenatal BPS is associated with asthma among males, but further research is required in cohorts with a greater proportion of prenatal urine samples with detectable BPS to validate these results.


Asunto(s)
Asma , Fenoles , Masculino , Humanos , Femenino , Embarazo , Estudios Prospectivos , Fenoles/toxicidad , Fenoles/orina , Compuestos de Bencidrilo/toxicidad , Compuestos de Bencidrilo/orina , Asma/inducido químicamente , Asma/epidemiología
8.
Environ Res ; 216(Pt 4): 114759, 2023 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-36370819

RESUMEN

BACKGROUND: Epidemiological study findings are inconsistent regarding associations between prenatal polycyclic aromatic hydrocarbon (PAH) exposures and childhood behavior. This study examined associations of prenatal PAH exposure with behavior at age 4-6 years in a large, diverse, multi-region prospective cohort. Secondary aims included examination of PAH mixtures and effect modification by child sex, breastfeeding, and child neighborhood opportunity. METHODS: The ECHO PATHWAYS Consortium pooled 1118 mother-child dyads from three prospective pregnancy cohorts in six U.S. cities. Seven PAH metabolites were measured in prenatal urine. Child behavior was assessed at age 4-6 using the Total Problems score from the Child Behavior Checklist (CBCL). Neighborhood opportunity was assessed using the socioeconomic and educational scales of the Child Opportunity Index. Multivariable linear regression was used to estimate associations per 2-fold increase in each PAH metabolite, adjusted for demographic, prenatal, and maternal factors and using interaction terms for effect modifiers. Associations with PAH mixtures were estimated using Weighted Quantile Sum Regression (WQSR). RESULTS: The sample was racially and sociodemographically diverse (38% Black, 49% White, 7% Other; household-adjusted income range $2651-$221,102). In fully adjusted models, each 2-fold increase in 2-hydroxynaphthalene was associated with a lower Total Problems score, contrary to hypotheses (b = -0.80, 95% CI = -1.51, -0.08). Associations were notable in boys (b = -1.10, 95% CI = -2.11, -0.08) and among children breastfed 6+ months (b = -1.31, 95% CI = -2.25, -0.37), although there was no statistically significant evidence for interaction by child sex, breastfeeding, or neighborhood child opportunity. Associations were null for other PAH metabolites; there was no evidence of associations with PAH mixtures from WQSR. CONCLUSION: In this large, well-characterized, prospective study of mother-child pairs, prenatal PAH exposure was not associated with child behavior problems. Future studies characterizing the magnitude of prenatal PAH exposure and studies in older childhood are needed.


Asunto(s)
Hidrocarburos Policíclicos Aromáticos , Efectos Tardíos de la Exposición Prenatal , Problema de Conducta , Embarazo , Masculino , Femenino , Preescolar , Humanos , Niño , Anciano , Hidrocarburos Policíclicos Aromáticos/toxicidad , Estudios Prospectivos , Efectos Tardíos de la Exposición Prenatal/inducido químicamente , Efectos Tardíos de la Exposición Prenatal/epidemiología , Estudios de Cohortes
9.
Financ Res Lett ; 54: 103790, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37056798

RESUMEN

The Covid-19 Pandemic has increased the attention paid to money market funds. Using Covid-19 cases and a measure of lockdowns, shutdowns, etc., we analyze if money market fund investors and managers responded to the intensity of the pandemic. We ask whether or not the Federal Reserve implementation of the Money Market Mutual Fund Liquidity Facility (MMLF) had an effect on market participant behavior. We find that institutional prime investors responded significantly to the MMLF. Fund managers responded to the intensity of the pandemic but largely ignored the reduction in uncertainty created by the implementation of the MMLF.

10.
J Neurosci ; 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-34088799

RESUMEN

The lateral (LA) and basolateral (BL) nuclei of the amygdala regulate emotional behaviors. Despite their dissimilar extrinsic connectivity, they are often combined, perhaps because their cellular composition is similar to that of the cerebral cortex, including excitatory principal cells reciprocally connected with fast-spiking interneurons (FSIs). In the cortex, this microcircuitry produces gamma oscillations that support information processing and behavior. We tested whether this was similarly the case in the rat (males) LA and BL using extracellular recordings, biophysical modeling, and behavioral conditioning. During periods of environmental assessment, both nuclei exhibited gamma oscillations that stopped upon initiation of active behaviors. Yet, BL exhibited more robust spontaneous gamma oscillations than LA. The greater propensity of BL to generate gamma resulted from several microcircuit differences, especially the proportion of FSIs and their interconnections with principal cells. Furthermore, gamma in BL but not LA regulated the efficacy of excitatory synaptic transmission between connected neurons. Together, these results suggest fundamental differences in how LA and BL operate. Most likely, gamma in LA is externally driven whereas in BL, it can also arise spontaneously to support ruminative processing and the evaluation of complex situations.SIGNIFICANCE STATEMENT:The basolateral amygdala (BLA) participates in the production and regulation of emotional behaviors. It is thought to perform this using feedforward circuits that enhance stimuli that gain emotional significance and directs them to valence-appropriate downstream effectors. This perspective overlooks the fact that its microcircuitry is recurrent and potentially capable of generating oscillations in the gamma band (50-80 Hz), which synchronize spiking activity and modulate communication between neurons. This study found that BLA gamma supports both these processes, is associated with periods of action selection and environmental assessment irrespective of valence, and differs between BLA subnuclei in a manner consistent with their heretofore unknown microcircuit differences. Thus, it provides new mechanisms for BLA to support emotional behaviors.

11.
BMC Public Health ; 22(1): 977, 2022 05 14.
Artículo en Inglés | MEDLINE | ID: mdl-35568894

RESUMEN

BACKGROUND: People incarcerated in US prisons have been disproportionately harmed by the COVID-19 pandemic. That prisons are such efficient superspreading environments can be attributed to several known factors: small, communal facilities where people are confined for prolonged periods of time; poor ventilation; a lack of non-punitive areas for quarantine/medical isolation; and staggeringly high numbers of people experiencing incarceration, among others. While health organizations have issued guidance on preventing and mitigating COVID-19 infection in carceral settings, little is known about if, when, and how recommendations have been implemented. We examined factors contributing to containment of one of the first California prison COVID-19 outbreaks and remaining vulnerabilities using an adapted multi-level determinants framework to systematically assess infectious disease risk in carceral settings. METHODS: Case study employing administrative data; observation; and informal discussions with: people incarcerated at the prison, staff, and county public health officials. RESULTS: Outbreak mitigation efforts were characterized by pre-planning (e.g., designation of ventilated, single-occupancy quarantine) and a quickly mobilized inter-institutional response that facilitated systematic, voluntary rapid testing. However, several systemic- and institutional-level vulnerabilities were unaddressed hindering efforts and posing significant risk for future outbreaks, including insufficient decarceration, continued inter-facility transfers, incomplete staff cohorting, and incompatibility between built environment features (e.g., dense living conditions) and public health recommendations. CONCLUSIONS: Our adapted framework facilitates systematically assessing prison-based infectious disease outbreaks and multi-level interventions. We find implementing some recommended public health strategies may have contributed to outbreak containment. However, even with a rapidly mobilized, inter-institutional response, failure to decarcerate created an overreliance on chance conditions. This left the facility vulnerable to future catastrophic outbreaks and may render standard public health strategies - including the introduction of effective vaccines - insufficient to prevent or contain those outbreaks.


Asunto(s)
COVID-19 , Prisioneros , COVID-19/prevención & control , Brotes de Enfermedades/prevención & control , Humanos , Pandemias/prevención & control , Prisiones , Salud Pública , SARS-CoV-2
12.
Clin J Sport Med ; 32(3): e316-e318, 2022 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-35316824

RESUMEN

ABSTRACT: Tarsal tunnel syndrome (TTS) typically occurs from extrinsic or intrinsic sources of compression on the tibial nerve. We present 3 cases of patients, all of whom have a prolonged time to diagnosis after evaluation with multiple specialties, with foot pain ultimately secondary to an accessory flexor digitorum longus muscle causing TTS. The literature describing the association between TTS and accessory musculature has been limited to single case reports and frequently demonstrate abnormal electrodiagnostic testing. In our series, 2 cases had normal electrodiagnostic findings despite magnetic resonance imaging (MRI) that later revealed TTS and improvement with eventual resection. A normal electromyogram should not preclude the diagnosis of TTS and MRI of the ankle; it should be considered a useful diagnostic tool when examining atypical foot pain.


Asunto(s)
Síndrome del Túnel Tarsiano , Tobillo , Pie/diagnóstico por imagen , Humanos , Músculo Esquelético/diagnóstico por imagen , Dolor , Síndrome del Túnel Tarsiano/diagnóstico , Síndrome del Túnel Tarsiano/etiología , Síndrome del Túnel Tarsiano/cirugía
13.
Sensors (Basel) ; 22(9)2022 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-35591067

RESUMEN

Tracheal intubation is the preferred method of airway management, a common emergency trauma medicine problem. Currently, methods for confirming tracheal tube placement are lacking, and we propose a novel technology, spectral reflectance, which may be incorporated into the tracheal tube for verification of placement. Previous work demonstrated a unique spectral profile in the trachea, which allowed differentiation from esophageal tissue in ex vivo swine, in vivo swine, and human cadavers. The goal of this study is to determine if spectral reflectance can differentiate between trachea and other airway tissues in living humans and whether the unique tracheal spectral profile persists in the presence of an inhalation injury. Reflectance spectra were captured using a custom fiber-optic probe from the buccal mucosa, posterior oropharynx, and trachea of healthy humans intubated for third molar extraction and from the trachea of patients admitted to a burn intensive care unit with and without inhalation injury. Using ratio comparisons, we found that the tracheal spectral profile was significantly different from buccal mucosa or posterior oropharynx, but the area under the curve values are not high enough to be used clinically. In addition, inhalation injury did not significantly alter the spectral reflectance of the trachea. Further studies are needed to determine the utility of this technology in a clinical setting and to develop an algorithm for tissue differentiation.


Asunto(s)
Intubación Intratraqueal , Tráquea , Animales , Cadáver , Tecnología de Fibra Óptica , Humanos , Respiración Artificial , Porcinos , Tráquea/lesiones
14.
J Neurophysiol ; 126(4): 1234-1247, 2021 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-34469705

RESUMEN

The central medial (CMT) and paraventricular (PVT) thalamic nuclei project strongly to the basolateral amygdala (BL). Similarities between the responsiveness of CMT, PVT, and BL neurons suggest that these nuclei strongly influence BL activity. Supporting this possibility, an electron microscopic study reported that, in contrast with other extrinsic afferents, CMT and PVT axon terminals form very few synapses with BL interneurons. However, since limited sampling is a concern in electron microscopic studies, the present investigation was undertaken to compare the impact of CMT and PVT thalamic inputs on principal and local-circuit BL neurons with optogenetic methods and whole cell recordings in vitro. Optogenetic stimulation of CMT and PVT axons elicited glutamatergic excitatory postsynaptic potentials (EPSPs) or excitatory postsynaptic currents (EPSCs) in principal cells and interneurons, but they generally had a longer latency in interneurons. Moreover, after blockade of polysynaptic interactions with tetrodotoxin (TTX), a lower proportion of interneurons (50%) than principal cells (90%) remained responsive to CMT and PVT inputs. Although the presence of TTX-resistant responses in some interneurons indicates that CMT and PVT inputs directly contact some local-circuit cells, their lower incidence and amplitude after TTX suggest that CMT and PVT inputs form fewer synapses with them than with principal BL cells. Together, these results indicate that CMT and PVT inputs mainly contact principal BL neurons such that when CMT or PVT neurons fire, limited feedforward inhibition counters their excitatory influence over principal BL cells. However, CMT and PVT axons can also recruit interneurons indirectly, via the activation of principal cells, thereby generating feedback inhibition.NEW & NOTEWORTHY Midline thalamic (MTh) nuclei contribute major projections to the basolateral amygdala (BL). Similarities between the responsiveness of MTh and BL neurons suggest that MTh neurons exert a significant influence over BL activity. Using optogenetic techniques, we show that MTh inputs mainly contact principal BL neurons such that when MTh neurons fire, little feedforward inhibition counters their excitatory influence over principal cells. Thus, MTh inputs may be major determinants of BL activity.


Asunto(s)
Complejo Nuclear Basolateral/fisiología , Potenciales Postsinápticos Excitadores/fisiología , Interneuronas/fisiología , Núcleos Talámicos de la Línea Media/fisiología , Inhibición Neural/fisiología , Animales , Femenino , Masculino , Optogenética , Ratas Long-Evans
15.
Appl Opt ; 59(23): 7045-7052, 2020 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-32788799

RESUMEN

We present a novel concept for a Thomson scattering diagnostic, based on a high-speed fiber optic spectrometer. The high-speed fiber optic spectrometer presented here translates a spectral measurement from the frequency domain into the time domain, thus requiring the use of only a single photodetector for spectral acquisition. The high temporal precision offered by the instrument gives rise to a number of advantages over traditional spectrometers, such as nearly background-free measurements and multiple uses of the same injected beam. Multiple uses of the same beam would enable greatly increased measurement rates, in the range of 10-100 MHz. The spectral range and resolution of the fiber spectrometer can be easily tailored to be optimized for the light source and experimental conditions by selecting different lengths of fiber, thus allowing for the proposed technique to exhibit high dynamic range when measuring many points simultaneously. Finally, due to the temporal separation of the background from the signal, these improvements are possible without the need for increased average input laser power.

16.
J Neurophysiol ; 121(5): 1761-1777, 2019 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-30840520

RESUMEN

Fear conditioning studies have led to the view that the amygdala contains neurons that signal threat and in turn elicit defensive behaviors through their brain stem and hypothalamic targets. In agreement with this model, a prior unit-recording study in rats performing a seminaturalistic foraging task revealed that many lateral amygdala (LA) neurons are predator responsive. In contrast, our previous study emphasized that most basolateral (BL) amygdala neurons are inhibited at proximity of the predator. However, the two studies used different methods to analyze unit activity, complicating comparisons between them. By applying the same method to the sample of BL neurons we recorded previously, the present study revealed that most principal cells are inhibited by the predator and only 4.5% are activated. Moreover, two-thirds of these cells were also activated by nonthreatening stimuli. In fact, fitting unit activity with a generalized linear model revealed that the only task variables associated with a prevalent positive modulation of BL activity were expectation of the predator's presence and whether the prior trial had been a failure or success. At odds with the threat-coding model of the amygdala, actual confrontation with the predator was usually associated with a widespread inhibition of principal BL neurons. NEW & NOTEWORTHY The basolateral amygdala (BL) is thought to contain neurons that signal threat, in turn eliciting defensive behaviors. In contrast, the present study reports that very few principal BL cells are responsive to threats and that most of them are also activated by nonthreatening stimuli. Yet, expectation of the threat's presence was associated with a prevalent positive modulation of BL activity; actual confrontation with the threat was associated with a widespread inhibition.


Asunto(s)
Amígdala del Cerebelo/fisiología , Condicionamiento Clásico , Miedo , Neuronas/fisiología , Potenciales de Acción , Amígdala del Cerebelo/citología , Animales , Masculino , Inhibición Neural , Ratas , Ratas Sprague-Dawley
17.
J Chem Phys ; 151(14): 144702, 2019 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-31615224

RESUMEN

Carrier scattering processes are studied in CH3NH3PbI3 using temperature-dependent four-wave mixing experiments. Our results indicate that scattering by ionized impurities limits the interband dephasing time (T2) below 30 K, with strong electron-phonon scattering dominating at higher temperatures (with a time scale of 125 fs at 100 K). Our theoretical simulations provide quantitative agreement with the measured carrier scattering rate and show that the rate of acoustic phonon scattering is enhanced by strong spin-orbit coupling, which modifies the band-edge density of states. The Rashba coefficient extracted from fitting the experimental results (γc = 2 eV Å) is in agreement with calculations of the surface Rashba effect and recent experiments using the photogalvanic effect on thin films.

18.
Afr J AIDS Res ; 18(4): 277-288, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31779568

RESUMEN

The past decade has seen a growing emphasis on the production of high-quality costing data to improve the efficiency and cost-effectiveness of global health interventions. The need for such data is especially important for decision making and priority setting across HIV services from prevention and testing to treatment and care. To help address this critical need, the Global Health Cost Consortium was created in 2016, in part to conduct a systematic search and screening of the costing literature for HIV and TB interventions in low- and middle-income countries (LMIC). The purpose of this portion of the remit was to compile, standardise, and make publicly available published cost data (peer-reviewed and gray) for public use. We limit our analysis to a review of the quantity and characteristics of published cost data from HIV interventions in sub-Saharan Africa. First, we document the production of cost data over 25 years, including density over time, geography, publication venue, authorship and type of intervention. Second, we explore key methods and reporting for characteristics including urbanicity, platform type, ownership and scale. Although the volume of HIV costing data has increased substantially on the continent, cost reporting is lacking across several dimensions. We find a dearth of cost estimates from HIV interventions in west Africa, as well as inconsistent reporting of key dimensions of cost including platform type, ownership and urbanicity. Further, we find clear evidence of a need for renewed focus on the consistent reporting of scale by authors of costing and cost-effectiveness analyses.


Asunto(s)
Infecciones por VIH/economía , Costos de la Atención en Salud/estadística & datos numéricos , África del Sur del Sahara , Análisis Costo-Beneficio , Salud Global/economía , Infecciones por VIH/diagnóstico , Infecciones por VIH/prevención & control , Infecciones por VIH/terapia , Servicios de Salud/economía , Humanos , Tuberculosis/diagnóstico , Tuberculosis/economía , Tuberculosis/prevención & control , Tuberculosis/terapia
19.
Afr J AIDS Res ; 18(4): 263-276, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31779571

RESUMEN

Consistently defined, accurate, and easily accessible cost data are a valuable resource to inform efficiency analyses, budget preparation, and sustainability planning in global health. The Global Health Cost Consortium (GHCC) designed the Unit Cost Study Repository (UCSR) to be a resource for standardised HIV and TB intervention cost data displayed by key characteristics such as intervention type, country, and target population. To develop the UCSR, the GHCC defined a typology of interventions for each disease; aligned interventions according to the standardised principles, methods, and cost and activity categories from the GHCC Reference Case for Estimating the Costs of Global Health Services and Interventions; completed a systematic literature review; conducted extensive data extraction; performed quality assurance; grappled with complex methodological issues such as the proper approach to the inflation and conversion of costs; developed and implemented a study quality rating system; and designed a web-based user interface that flexibly displays large amounts of data in a user-friendly way. Key lessons learned from the extraction process include the importance of assessing the multiple uses of extracted data; the critical role of standardising definitions (particularly units of measurement); using appropriate classifications of interventions and components of costs; the efficiency derived from programming data checks; and the necessity of extraction quality monitoring by senior analysts. For the web interface, lessons were: understanding the target audiences, including consulting them regarding critical characteristics; designing the display of data in "levels"; and incorporating alert and unique trait descriptions to further clarify differences in the data.


Asunto(s)
Salud Global/economía , Infecciones por VIH/economía , Costos de la Atención en Salud/normas , Tuberculosis/economía , Recolección de Datos , Infecciones por VIH/prevención & control , Costos de la Atención en Salud/estadística & datos numéricos , Servicios de Salud/economía , Humanos , Estándares de Referencia , Revisiones Sistemáticas como Asunto , Tuberculosis/prevención & control , Interfaz Usuario-Computador
20.
Afr J AIDS Res ; 18(4): 341-349, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31779565

RESUMEN

Objective: Explore facility-level average costs per client of HIV testing and counselling (HTC) and voluntary medical male circumcision (VMMC) services in 13 countries.Methods: Through a literature search we identified studies that reported facility-level costs of HTC or VMMC programmes. We requested the primary data from authors and standardised the disparate data sources to make them comparable. We then conducted descriptive statistics and a meta-analysis to assess the cost variation among facilities. All costs were converted to 2017 US dollars ($).Results: We gathered data from 14 studies across 13 countries and 772 facilities (552 HTC, 220 VMMC). The weighted average unit cost per client served was $15 (95% CI 12, 18) for HTC and $59 (95% CI 45, 74) for VMMC. On average, 38% of the mean unit cost for HTC corresponded to recurrent costs, 56% to personnel costs, and 6% to capital costs. For VMMC, 41% of the average unit cost corresponded to recurrent costs, 55% to personnel costs, and 4% to capital costs. We observed unit cost variation within and between countries, and lower costs in higher scale categories in all interventions.


Asunto(s)
Circuncisión Masculina/economía , Consejo/economía , Infecciones por VIH/diagnóstico , Infecciones por VIH/prevención & control , Tamizaje Masivo/economía , Costos y Análisis de Costo , Infecciones por VIH/economía , Instituciones de Salud , Humanos , Masculino
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