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1.
Proc Natl Acad Sci U S A ; 120(44): e2308828120, 2023 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-37871204

RESUMEN

Here, a molecular-design and carbon dot-confinement coupling strategy through the pyrolysis of bimetallic complex of diethylenetriamine pentaacetic acid under low-temperature is proposed as a universal approach to dual-metal-atom sites in carbon dots (DMASs-CDs). CDs as the "carbon islands" could block the migration of DMASs across "islands" to achieve dynamic stability. More than twenty DMASs-CDs with specific compositions of DMASs (pairwise combinations among Fe, Co, Ni, Mn, Zn, Cu, and Mo) have been synthesized successfully. Thereafter, high intrinsic activity is observed for the probe reaction of urea oxidation on NiMn-CDs. In situ and ex situ spectroscopic characterization and first-principle calculations unveil that the synergistic effect in NiMn-DMASs could stretch the urea molecule and weaken the N-H bond, endowing NiMn-CDs with a low energy barrier for urea dehydrogenation. Moreover, DMASs-CDs for various target electrochemical reactions, including but not limited to urea oxidation, are realized by optimizing the specific DMAS combination in CDs.

2.
Proc Natl Acad Sci U S A ; 120(18): e2207537120, 2023 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-37098064

RESUMEN

Policymakers must make management decisions despite incomplete knowledge and conflicting model projections. Little guidance exists for the rapid, representative, and unbiased collection of policy-relevant scientific input from independent modeling teams. Integrating approaches from decision analysis, expert judgment, and model aggregation, we convened multiple modeling teams to evaluate COVID-19 reopening strategies for a mid-sized United States county early in the pandemic. Projections from seventeen distinct models were inconsistent in magnitude but highly consistent in ranking interventions. The 6-mo-ahead aggregate projections were well in line with observed outbreaks in mid-sized US counties. The aggregate results showed that up to half the population could be infected with full workplace reopening, while workplace restrictions reduced median cumulative infections by 82%. Rankings of interventions were consistent across public health objectives, but there was a strong trade-off between public health outcomes and duration of workplace closures, and no win-win intermediate reopening strategies were identified. Between-model variation was high; the aggregate results thus provide valuable risk quantification for decision making. This approach can be applied to the evaluation of management interventions in any setting where models are used to inform decision making. This case study demonstrated the utility of our approach and was one of several multimodel efforts that laid the groundwork for the COVID-19 Scenario Modeling Hub, which has provided multiple rounds of real-time scenario projections for situational awareness and decision making to the Centers for Disease Control and Prevention since December 2020.


Asunto(s)
COVID-19 , Humanos , COVID-19/epidemiología , COVID-19/prevención & control , Incertidumbre , Brotes de Enfermedades/prevención & control , Salud Pública , Pandemias/prevención & control
3.
PLoS Med ; 21(4): e1004387, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38630802

RESUMEN

BACKGROUND: Coronavirus Disease 2019 (COVID-19) continues to cause significant hospitalizations and deaths in the United States. Its continued burden and the impact of annually reformulated vaccines remain unclear. Here, we present projections of COVID-19 hospitalizations and deaths in the United States for the next 2 years under 2 plausible assumptions about immune escape (20% per year and 50% per year) and 3 possible CDC recommendations for the use of annually reformulated vaccines (no recommendation, vaccination for those aged 65 years and over, vaccination for all eligible age groups based on FDA approval). METHODS AND FINDINGS: The COVID-19 Scenario Modeling Hub solicited projections of COVID-19 hospitalization and deaths between April 15, 2023 and April 15, 2025 under 6 scenarios representing the intersection of considered levels of immune escape and vaccination. Annually reformulated vaccines are assumed to be 65% effective against symptomatic infection with strains circulating on June 15 of each year and to become available on September 1. Age- and state-specific coverage in recommended groups was assumed to match that seen for the first (fall 2021) COVID-19 booster. State and national projections from 8 modeling teams were ensembled to produce projections for each scenario and expected reductions in disease outcomes due to vaccination over the projection period. From April 15, 2023 to April 15, 2025, COVID-19 is projected to cause annual epidemics peaking November to January. In the most pessimistic scenario (high immune escape, no vaccination recommendation), we project 2.1 million (90% projection interval (PI) [1,438,000, 4,270,000]) hospitalizations and 209,000 (90% PI [139,000, 461,000]) deaths, exceeding pre-pandemic mortality of influenza and pneumonia. In high immune escape scenarios, vaccination of those aged 65+ results in 230,000 (95% confidence interval (CI) [104,000, 355,000]) fewer hospitalizations and 33,000 (95% CI [12,000, 54,000]) fewer deaths, while vaccination of all eligible individuals results in 431,000 (95% CI: 264,000-598,000) fewer hospitalizations and 49,000 (95% CI [29,000, 69,000]) fewer deaths. CONCLUSIONS: COVID-19 is projected to be a significant public health threat over the coming 2 years. Broad vaccination has the potential to substantially reduce the burden of this disease, saving tens of thousands of lives each year.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Hospitalización , SARS-CoV-2 , Vacunación , Humanos , Vacunas contra la COVID-19/inmunología , COVID-19/prevención & control , COVID-19/epidemiología , COVID-19/inmunología , Estados Unidos/epidemiología , Anciano , Hospitalización/estadística & datos numéricos , SARS-CoV-2/inmunología , Persona de Mediana Edad , Adulto , Adolescente , Adulto Joven , Niño , Anciano de 80 o más Años , Masculino
4.
Small ; : e2403029, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38966884

RESUMEN

Hydrogen peroxide (H2O2) plays a pivotal role in advancing sustainable technologies due to its eco-friendly oxidizing capability. The electrochemical two-electron (2e-) oxygen reduction reaction and water oxidation reaction present an environmentally green method for H2O2 production. Over the past three years, significant progress is made in the field of carbon-based metal-free electrochemical catalysts (C-MFECs) for low-cost and efficient production of H2O2 (H2O2EP). This article offers a focused and comprehensive review of designing C-MFECs for H2O2EP, exploring the construction of dual-doping configurations, heteroatom-defect coupling sites, and strategic dopant positioning to enhance H2O2EP efficiency; innovative structural tuning that improves interfacial reactant concentration and promote the timely release of H2O2; modulation of electrolyte and electrode interfaces to support the 2e- pathways; and the application of C-MFECs in reactors and integrated energy systems. Finally, the current challenges and future directions in this burgeoning field are discussed.

5.
J Gen Intern Med ; 39(4): 643-651, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37932543

RESUMEN

BACKGROUND: Risk stratification and population management strategies are critical for providing effective and equitable care for the growing population of older adults in the USA. Both frailty and neighborhood disadvantage are constructs that independently identify populations with higher healthcare utilization and risk of adverse outcomes. OBJECTIVE: To examine the joint association of these factors on acute healthcare utilization using two pragmatic measures based on structured data available in the electronic health record (EHR). DESIGN: In this retrospective observational study, we used EHR data to identify patients aged ≥ 65 years at Atrium Health Wake Forest Baptist on January 1, 2019, who were attributed to affiliated Accountable Care Organizations. Frailty was categorized through an EHR-derived electronic Frailty Index (eFI), while neighborhood disadvantage was quantified through linkage to the area deprivation index (ADI). We used a recurrent time-to-event model within a Cox proportional hazards framework to examine the joint association of eFI and ADI categories with healthcare utilization comprising emergency visits, observation stays, and inpatient hospitalizations over one year of follow-up. KEY RESULTS: We identified a cohort of 47,566 older adults (median age = 73, 60% female, 12% Black). There was an interaction between frailty and area disadvantage (P = 0.023). Each factor was associated with utilization across categories of the other. The magnitude of frailty's association was larger than living in a disadvantaged area. The highest-risk group comprised frail adults living in areas of high disadvantage (HR 3.23, 95% CI 2.99-3.49; P < 0.001). We observed additive effects between frailty and living in areas of mid- (RERI 0.29; 95% CI 0.13-0.45; P < 0.001) and high (RERI 0.62, 95% CI 0.41-0.83; P < 0.001) neighborhood disadvantage. CONCLUSIONS: Considering both frailty and neighborhood disadvantage may assist healthcare organizations in effectively risk-stratifying vulnerable older adults and informing population management strategies. These constructs can be readily assessed at-scale using routinely collected structured EHR data.


Asunto(s)
Fragilidad , Humanos , Femenino , Anciano , Masculino , Fragilidad/epidemiología , Visitas a la Sala de Emergencias , Estudios Retrospectivos , Hospitalización , Características del Vecindario
6.
Stat Med ; 43(1): 125-140, 2024 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-37942694

RESUMEN

Timeline followback (TLFB) is often used in addiction research to monitor recent substance use, such as the number of abstinent days in the past week. TLFB data usually take the form of binomial counts that exhibit overdispersion and zero inflation. Motivated by a 12-week randomized trial evaluating the efficacy of varenicline tartrate for smoking cessation among adolescents, we propose a Bayesian zero-inflated beta-binomial model for the analysis of longitudinal, bounded TLFB data. The model comprises a mixture of a point mass that accounts for zero inflation and a beta-binomial distribution for the number of days abstinent in the past week. Because treatment effects appear to level off during the study, we introduce random changepoints for each study group to reflect group-specific changes in treatment efficacy over time. The model also includes fixed and random effects that capture group- and subject-level slopes before and after the changepoints. Using the model, we can accurately estimate the mean trend for each study group, test whether the groups experience changepoints simultaneously, and identify critical windows of treatment efficacy. For posterior computation, we propose an efficient Markov chain Monte Carlo algorithm that relies on easily sampled Gibbs and Metropolis-Hastings steps. Our application shows that the varenicline group has a short-term positive effect on abstinence that tapers off after week 9.


Asunto(s)
Modelos Estadísticos , Trastornos Relacionados con Sustancias , Adolescente , Humanos , Teorema de Bayes , Distribución Binomial , Algoritmos
7.
Macromol Rapid Commun ; 45(11): e2300717, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38445752

RESUMEN

This work presents a rheological study of a biocompatible and biodegradable liquid crystal elastomer (LCE) ink for three dimensional (3D) printing. These materials have shown that their structural variations have an effect on morphology, mechanical properties, alignment, and their impact on cell response. Within the last decade LCEs are extensively studied as potential printing materials for soft robotics applications, due to the actuation properties that are produced when liquid crystal (LC) moieties are induced through external stimuli. This report utilizes experiments and coarse-grained molecular dynamics to study the macroscopic rheology of LCEs in nonlinear shear flow. Results from the shear flow simulations are in line with the outcomes of these experimental investigations. This work believes the insights from these results can be used to design and print new material with desirable properties necessary for targeted applications.


Asunto(s)
Elastómeros , Cristales Líquidos , Simulación de Dinámica Molecular , Impresión Tridimensional , Reología , Elastómeros/química , Cristales Líquidos/química , Materiales Biocompatibles/química
8.
Metab Brain Dis ; 38(3): 805-817, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36745251

RESUMEN

Modulation of cell signaling pathways is the key area of research towards the treatment of neurodegenerative disorders. Altered Nrf2-Keap1-ARE (Nuclear factor erythroid-2-related factor 2-Kelch-like ECH-associated protein 1-Antioxidant responsive element) and SIRT1 (Sirtuin 1) cell signaling pathways are considered to play major role in the etiology and pathogenesis of Alzheimer's disease (AD) and Parkinson's disease (PD). Strikingly, betanin, a betanidin 5-O-ß-D-glucoside compound is reported to show commendable anti-oxidative, anti-inflammatory and anti-apoptotic effects in several disease studies including AD and PD. The present review discusses the pre-clinical studies demonstrating the neuroprotective effects of betanin by virtue of its potential to ameliorate oxidative stress, neuroinflammation, abnormal protein aggregation and cell death. It highlights the direct linkage between the neuroprotective abilities of betanin and upregulation of the Nrf2-Keap1-ARE and SIRT1 signaling pathways. The review further hypothesizes the involvement of the betanin-Nrf2-ARE route in the inhibition of beta-amyloid aggregation through beta-site amyloid precursor protein cleaving enzyme 1 (BACE1), one of the pivotal hallmarks of AD. The present review hereby for the first time elaborately discusses the reported neuroprotective abilities of betanin and decodes the Nrf2 and SIRT1 modulating potential of betanin as a primary mechanism of action behind, hence highlighting it as a novel drug candidate for the treatment of neurodegenerative diseases in the near future.


Asunto(s)
Enfermedad de Alzheimer , Enfermedad de Parkinson , Humanos , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/metabolismo , Enfermedad de Parkinson/tratamiento farmacológico , Neuroprotección , Betacianinas , Proteína 1 Asociada A ECH Tipo Kelch , Secretasas de la Proteína Precursora del Amiloide/metabolismo , Sirtuina 1/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Ácido Aspártico Endopeptidasas/metabolismo , Transducción de Señal , Estrés Oxidativo
9.
Stat Med ; 41(21): 4159-4175, 2022 09 20.
Artículo en Inglés | MEDLINE | ID: mdl-35718471

RESUMEN

Real-time trends from surveillance data are important to assess and develop preparedness for influenza outbreaks. The overwhelming testing demand and limited capacity of testing laboratories for viral positivity render daily confirmed case data inaccurate and delay its availability in preparedness. Using Bayesian dynamic downscaling models, we obtained posterior estimates for daily influenza incidences from weekly estimates of the Centers for Disease Control and Prevention and daily reported constitutional and respiratory complaints during emergency department (ED) visits obtained from the state health departments. Our model provides one-day and seven-day lead forecasts along with 95 % $$ \% $$ prediction intervals. Our hybrid Markov Chain Monte Carlo and Kalman filter algorithms facilitate faster computation and enable us to update our estimates as new data become available. Our method is tested and validated using the State of Michigan data over the years 2009-2013. Reported constitutional and respiratory complaints at the EDs showed strong correlations of 0.81 and 0.68 respectively, with influenza rates. In general, our forecast model can be adapted to track an outbreak with only one respiratory virus as a causative agent.


Asunto(s)
Gripe Humana , Teorema de Bayes , Brotes de Enfermedades , Servicio de Urgencia en Hospital , Predicción , Humanos , Gripe Humana/epidemiología , Gripe Humana/prevención & control
10.
Exp Brain Res ; 240(1): 113-122, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34633467

RESUMEN

Although the etiology of Parkinson's disease (PD) is poorly understood, studies in animal models revealed loss of dopamine and the dopaminergic neurons harbouring the neurotransmitter to be the principal cause behind this neuro-motor disorder. Neuroinflammation with glial cell activation is suggested to play a significant role in dopaminergic neurodegeneration. Several biomolecules have been reported to confer dopaminergic neuroprotection in different animal models of PD, owing to their anti-inflammatory potentials. Garcinol is a tri-isoprenylated benzophenone isolated from Garcinia sp. and accumulating evidences suggest that this molecule could provide neuroprotection by modulating oxidative stress and inflammation. However, direct evidence of dopaminergic neuroprotection by garcinol in the pre-clinical model of PD is not yet reported. The present study aims to investigate whether administration of garcinol in the MPTP mouse model of PD may ameliorate the cardinal motor behavioural deficits and prevent the loss of dopaminergic neurons. As expected, garcinol blocked the parkinsonian motor behavioural deficits which include akinesia, catalepsy, and rearing anomalies in the mice model. Most importantly, the degeneration of dopaminergic cell bodies in the substantia nigra region was significantly prevented by garcinol. Furthermore, garcinol reduced the inflammatory marker, glial fibrillary acidic protein, in the substantia nigra region. Since glial hyperactivation-mediated inflammation is inevitably associated with the loss of dopaminergic neurons, our study suggests the anti-inflammatory role of garcinol in facilitating dopaminergic neuroprotection in PD mice. Hence, in the light of the present study, it is suggested that garcinol is an effective anti-parkinsonian agent to block motor behavioural deficits and dopaminergic neurodegeneration in PD.


Asunto(s)
Enfermedad de Parkinson , 1-Metil-4-fenil-1,2,3,6-Tetrahidropiridina , Animales , Antiinflamatorios , Modelos Animales de Enfermedad , Dopamina , Neuronas Dopaminérgicas , Ratones , Ratones Endogámicos C57BL , Neuroprotección , Sustancia Negra , Terpenos
11.
Metab Brain Dis ; 37(6): 1887-1900, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35622265

RESUMEN

Dopaminergic neuroprotection is the main interest in designing novel therapeutics against Parkinson's disease (PD). In the process of dopaminergic degeneration, mitochondrial dysfunctions and inflammation are significant. While the existing drugs provide symptomatic relief against PD, a therapy conferring total neuroprotection by targeting multiple degenerative pathways is still lacking. Garcinia morella is a common constituent of Ayurvedic medication and has been used for the treatment of inflammatory disorders. The present study investigates whether administration of G. morella fruit extract (GME) in MPTP mouse model of PD protects against dopaminergic neurodegeneration, including the underlying pathophysiologies, and reverses the motor behavioural abnormalities. Administration of GME prevented the loss of dopaminergic cell bodies in the substantia nigra and its terminals in the corpus striatum of PD mice. Subsequently, reversal of parkinsonian behavioural abnormalities, viz. akinesia, catalepsy, and rearing, was observed along with the recovery of striatal dopamine and its metabolites in the experimental model. Furthermore, reduced activity of the mitochondrial complex II in the nigrostriatal pathway of brain of the mice was restored after the administration of GME. Also, MPTP-induced enhanced activation of Glial fibrillary acidic protein (GFAP) and neuronal nitric oxide synthase (nNOS) in the nigrostriatal pathway, which are the markers of inflammatory stress, were found to be ameliorated on GME treatment. Thus, our study presented a novel mode of dopaminergic neuroprotection by G. morella in PD by targeting the mitochondrial dysfunctions and neuroinflammation, which are considered to be intricately associated with the loss of dopaminergic neurons.


Asunto(s)
Garcinia , Enfermedad de Parkinson , 1-Metil-4-fenil-1,2,3,6-Tetrahidropiridina/metabolismo , Animales , Cuerpo Estriado/metabolismo , Modelos Animales de Enfermedad , Dopamina/metabolismo , Neuronas Dopaminérgicas/metabolismo , Garcinia/metabolismo , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Ratones , Ratones Endogámicos C57BL , Mitocondrias/metabolismo , Neuroprotección , Enfermedad de Parkinson/metabolismo , Sustancia Negra/metabolismo
12.
Am J Ind Med ; 65(4): 262-267, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35133653

RESUMEN

BACKGROUND: Coal workers' pneumoconiosis (CWP) is an occupational lung disease due to inhalation of coal dust. We estimated mortality from CWP and other pneumoconioses among Medicare beneficiaries. METHODS: We used the 5% Medicare Limited Claims Data Set, 2011-2014, to identify patients diagnosed with ICD-9-CM 500 (CWP) through 505 (Asbestosis, Pneumoconiosis due to other silica or silicates, Pneumoconiosis due to other inorganic dust, Pneumonopathy due to inhalation of other dust, and Pneumoconiosis, unspecified) codes. We applied binary regression models with spatial random effects to determine the association between CWP and mortality. Our inferences are based on Bayesian spatial hierarchical models, and model fitting was performed using Integrated Nested Laplace Approximation (INLA) algorithm in R/RStudio software. RESULTS: The median age of the sample was 76 years. In a sample of 8531 Medicare beneficiaries, 2568 died. Medicare beneficiaries with CWP had 25% higher odds of death (adjusted OR: 1.25, 95% CI: 1.07, 1.46) than those with other types of pneumoconiosis. The number of comorbid conditions elevated the odds of death by 10% (adjusted OR: 1.10, 95% CI: 1.09, 1.10). CONCLUSION: CWP increases the likelihood of death among Medicare beneficiaries. Healthcare professionals should make concerted efforts to monitor patients with CWP to prevent premature mortality.


Asunto(s)
Antracosis , Minas de Carbón , Neumoconiosis , Anciano , Teorema de Bayes , Carbón Mineral , Polvo , Humanos , Medicare , Estados Unidos/epidemiología
13.
Chem Soc Rev ; 50(21): 11785-11843, 2021 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-34559871

RESUMEN

Since the discovery of N-doped carbon nanotubes as the first carbon-based metal-free electrocatalyst (C-MFEC) for oxygen reduction reaction (ORR) in 2009, C-MFECs have shown multifunctional electrocatalytic activities for many reactions beyond ORR, such as oxygen evolution reaction (OER), hydrogen evolution reaction (HER), carbon dioxide reduction reaction (CO2RR), nitrogen reduction reaction (NRR), and hydrogen peroxide production reaction (H2O2PR). Consequently, C-MFECs have attracted a great deal of interest for various applications, including metal-air batteries, water splitting devices, regenerative fuel cells, solar cells, fuel and chemical production, water purification, to mention a few. By altering the electronic configuration and/or modulating their spin angular momentum, both heteroatom(s) doping and structural defects (e.g., atomic vacancy, edge) have been demonstrated to create catalytic active sites in the skeleton of graphitic carbon materials. Although certain C-MFECs have been made to be comparable to or even better than their counterparts based on noble metals, transition metals and/or their hybrids, further research and development are necessary in order to translate C-MFECs for practical applications. In this article, we present a timely and comprehensive, but critical, review on recent advancements in the field of C-MFECs within the past five years or so by discussing various types of electrocatalytic reactions catalyzed by C-MFECs. An emphasis is given to potential applications of C-MFECs for energy conversion and storage. The structure-property relationship for and mechanistic understanding of C-MFECs will also be discussed, along with the current challenges and future perspectives.

14.
Sensors (Basel) ; 22(16)2022 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-36015706

RESUMEN

In cognitive radio networks (CRNs), two secondary users (SUs) need to meet on a channel among multiple channels within a finite time to establish a link, which is called rendezvous. For blind rendezvous, researchers have devised ample well-grounded channel hopping (CH) sequences that guarantee smaller time-to-rendezvous. However, the best part of these works lacks the impact of network factors, particularly channel availability and collision during rendezvous. In this study, a new CH scheme is investigated by jointly considering the medium access control (MAC) protocol for single-hop multi-user CRNs. The analysis of our new variable hopping sequence (V-HS) guarantees rendezvous for the asymmetric channel model within a finite time. Although this mathematical concept guarantees rendezvous between two SUs, opportunities can be overthrown because of the unsuccessful exchange of control packets on that channel. A successful rendezvous also requires the exchange of messages reliably while two users visit the same channel. We propose a MAC protocol, namely ReMAC, that can work with V-HS and CH schemes. This design allows multiple rendezvous opportunities when a certain user visits the channel and modifies the conventional back-off strategy to maintain the channel list. Both simulation and analytical results exhibited improved performance over the previous approaches.


Asunto(s)
Redes de Comunicación de Computadores , Tecnología Inalámbrica , Algoritmos , Cognición , Simulación por Computador
15.
BMC Public Health ; 21(1): 1361, 2021 07 09.
Artículo en Inglés | MEDLINE | ID: mdl-34243730

RESUMEN

BACKGROUND: Individuals may use unhealthy coping mechanisms such as alcohol, tobacco, and unhealthy snack consumption. The purpose of this study was to assess how neighborhood disadvantage is associated with sales of alcohol, tobacco, and unhealthy snacks at stores of a discount variety store chain. METHODS: Alcohol, tobacco, and unhealthy snack sales were measured monthly for 20 months, 2017-2018, in 16 discount variety stores in the United States. Mixed effects linear regressions adjusted for population size, with store-specific random effects, to examine the relationship of weekly unit sales with three outcome variables and neighborhood disadvantage, measured using the Area Deprivation Index (ADI). RESULTS: The discount variety stores were located in neighborhoods where the median ADI percentile was 87 [interquartile range 83,89], compared to the median ADI percentile of 50 for all US communities, indicating that the stores were located in substantially disadvantaged neighborhoods. For every 1% increase in ADI, weekly unit sales of unhealthy snack food increased by 43 [95% confidence interval, CI 28-57], and weekly unit sales of tobacco products increased by 11.5 [95% CI 5-18] per store. No significant relationship between neighborhood disadvantage and the weekly unit sales of alcohol products was identified. CONCLUSIONS: The positive relationship between neighborhood disadvantage and the sale of tobacco and snack foods may help explain the pathway between neighborhood disadvantage and poor health outcomes. It would be useful for future research to examine how neighborhood disadvantage influences resident health-related behaviors.


Asunto(s)
Bocadillos , Productos de Tabaco , Comercio , Humanos , Características de la Residencia , Nicotiana , Estados Unidos/epidemiología
16.
Am J Ind Med ; 63(6): 478-483, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32147857

RESUMEN

BACKGROUND: Workers employed in the coal mining sector are at increased risk of respiratory diseases, including coal workers' pneumoconiosis (CWP). We investigated the prevalence of CWP and its association with sociodemographic factors among Medicare beneficiaries. METHODS: We used 5% Medicare Limited Data Set claims data from 2011 to 2014 to select Medicare beneficiaries with a diagnosis of ICD-9-CM 500 (CWP). We aggregated the data by county and limited our analysis to seven contiguous states: Illinois, Indiana, Kentucky, Ohio, Pennsylvania, Virginia, and West Virginia. We estimated county-level prevalence rates using total Medicare beneficiaries and miners as denominators and performed spatial hotspot analysis. We used negative binomial regression analysis to determine the association of county-wise sociodemographic factors with CWP. RESULTS: There was significant spatial clustering of CWP cases in Kentucky, Virginia, and West Virginia. Spatial clusters of 210 and 605 CWP cases representing an estimated 4200 to 12 100 cases of Medicare beneficiaries with CWP were identified in the three states. Counties with higher poverty levels had a significantly elevated rate of CWP (adjusted rate ratios [RR]: 1.15; 95% CI, 1.12-1.18). There was a small but significant association of CWP with the county-wise catchment area. Rurality was associated with a more than three-fold elevated rate of CWP in the unadjusted analysis (RR: 3.28, 95% CI, 2.22-4.84). However, the rate declined to 1.45 (95% CI, 1.04-2.01) after adjusting for other factors in the analysis. CONCLUSIONS: We found evidence of significant spatial clustering of CWP among Medicare beneficiaries living in the seven states of the USA.


Asunto(s)
Antracosis/epidemiología , Punto Alto de Contagio de Enfermedades , Medicare/estadística & datos numéricos , Anciano , Anciano de 80 o más Años , Análisis por Conglomerados , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Estados Unidos/epidemiología
17.
Environ Geochem Health ; 42(11): 3819-3839, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32601907

RESUMEN

Monitoring the groundwater chemical composition and identifying the presence of pollutants is an integral part of any comprehensive groundwater management strategy. The present study was conducted in a part of West Tripura, northeast India, to investigate the presence and sources of trace metals in groundwater and the risk to human health due to direct ingestion of groundwater. Samples were collected from 68 locations twice a year from 2016 to 2018. Mixed Ca-Mg-HCO3, Ca-Cl and Ca-Mg-Cl were the main groundwater types. Hydrogeochemical methods showed groundwater mineralization due to (1) carbonate dissolution, (2) silicate weathering, (3) cation exchange processes and (4) anthropogenic sources. Occurrence of faecal coliforms increased in groundwater after monsoons. Nitrate and microbial contamination from wastewater infiltration were apparent. Iron, manganese, lead, cadmium and arsenic were above the drinking water limits prescribed by the Bureau of Indian Standards. Water quality index indicated 1.5% had poor, 8.7% had marginal, 16.2% had fair, 66.2% had good and 7.4% had excellent water quality. Correlation and principal component analysis reiterated the sources of major ions and trace metals identified from hydrogeochemical methods. Human exposure assessment suggests health risk due to high iron in groundwater. The presence of unsafe levels of trace metals in groundwater requires proper treatment measures before domestic use.


Asunto(s)
Agua Subterránea/análisis , Metales/análisis , Oligoelementos/análisis , Contaminantes Químicos del Agua/análisis , Calidad del Agua , Carbonatos/análisis , Carbonatos/química , Exposición Dietética/efectos adversos , Exposición Dietética/análisis , Agua Potable/análisis , Monitoreo del Ambiente/métodos , Heces/microbiología , Agua Subterránea/química , Agua Subterránea/microbiología , Humanos , Hidrología/métodos , India , Nitratos/análisis , Medición de Riesgo/métodos , Aguas Residuales/análisis , Aguas Residuales/microbiología , Microbiología del Agua
18.
Sex Transm Infect ; 94(5): 353-358, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29358526

RESUMEN

OBJECTIVE: We modelled individual vulnerability to STI using personal history of infection and neighbourhood characteristics. METHODS: Retrospective chlamydia and gonorrhoea data of reported confirmed cases from Kalamazoo County, Michigan for 2012 through 2014 were analysed. Unique IDs were generated from the surveillance data in collaboration with local health officials to track the individual STI histories. We then examine the concept that individuals with similar STI histories form a 'peer' group. These peer group include: (1) individuals with a single chlamydia; (2) individuals with single gonorrhoea; (3) individuals with repeated cases of one type of STI and (4) individuals that were diagnosed with both infections during the study period. Using Kernel density estimation, we generated densities for each peer group and assigned the intensity of the infection to the location of the individual. Finally, the individual vulnerability was characterised through ordinary least square regression (OLS) using demographics and socioeconomic variables. RESULTS: In an OLS regression adjusted for frequency of infection, individual vulnerability to STI was only consistently significant for race and neighbourhood-level socioeconomic status (SES) in all the models under consideration. In addition, we identified six areas in three townships in Kalamazoo County that could be considered for unique interventions based on overlap patterns among peer groups. CONCLUSIONS: The results provide evidence that individual vulnerability to STI has some dependency on individual contextual (race) and exogenous factors at the neighbourhood level such as SES, regardless of that individual's personal history of infection. We suggest place-based intervention strategies be adopted for planning STI interventions instead of current universal screening of at-risk populations.


Asunto(s)
Interpretación Estadística de Datos , Monitoreo Epidemiológico , Modelos Estadísticos , Enfermedades de Transmisión Sexual/epidemiología , Enfermedades de Transmisión Sexual/prevención & control , Adolescente , Adulto , Infecciones por Chlamydia/epidemiología , Infecciones por Chlamydia/prevención & control , Femenino , Gonorrea/epidemiología , Gonorrea/prevención & control , Infecciones por VIH/epidemiología , Infecciones por VIH/prevención & control , Humanos , Masculino , Michigan/epidemiología , Grupo Paritario , Análisis de Componente Principal , Análisis de Regresión , Estudios Retrospectivos , Sífilis/epidemiología , Sífilis/prevención & control , Adulto Joven
19.
Nanotechnology ; 29(11): 115705, 2018 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-29323661

RESUMEN

X-ray photoelectron spectroscopy (XPS) has been utilized as a versatile method for thickness characterization of various two-dimensional (2D) films. Accurate thickness can be measured simultaneously while acquiring XPS data for chemical characterization of 2D films having thickness up to approximately 10 nm. For validating the developed technique, thicknesses of few-layer graphene (FLG), MoS2 and amorphous boron nitride (a-BN) layer, produced by microwave plasma chemical vapor deposition (MPCVD), plasma enhanced chemical vapor deposition (PECVD), and pulsed laser deposition (PLD) respectively, were accurately measured. The intensity ratio between photoemission peaks recorded for the films (C 1s, Mo 3d, B 1s) and the substrates (Cu 2p, Al 2p, Si 2p) is the primary input parameter for thickness calculation, in addition to the atomic densities of the substrate and the film, and the corresponding electron attenuation length (EAL). The XPS data was used with a proposed model for thickness calculations, which was verified by cross-sectional transmission electron microscope (TEM) measurement of thickness for all the films. The XPS method determines thickness values averaged over an analysis area which is orders of magnitude larger than the typical area in cross-sectional TEM imaging, hence provides an advanced approach for thickness measurement over large areas of 2D materials. The study confirms that the versatile XPS method allows rapid and reliable assessment of the 2D material thickness and this method can facilitate in tailoring growth conditions for producing very thin 2D materials effectively over a large area. Furthermore, the XPS measurement for a typical 2D material is non-destructive and does not require special sample preparation. Therefore, after XPS analysis, exactly the same sample can undergo further processing or utilization.

20.
Biochim Biophys Acta ; 1860(9): 1989-97, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27318154

RESUMEN

BACKGROUND: Dopamine replacement therapy by its precursor, L-3.4-dihydroxyphenylalanine (L-DOPA), has been the treatment of choice for Parkinson's disease. However, the possible contributory effect of L-DOPA therapy on the progression of Parkinson's disease mediated by the L-DOPA-induced toxic metabolites remains elusive. SCOPE OF REVIEW: Prolong use of L-DOPA leads to behavioral impediments and instigate the generation of several toxic metabolites. One such metabolite is homocysteine, the level of which increases in the plasma of Parkinson's disease patients undergoing L-DOPA therapy, as well as in brain of animal models of the disease. In concoction with parkinsonian neurotoxins, Hcy exaggerates dopaminergic neurodegeneration, while its intranigral infusion has been demonstrated to decrease the dopamine level as well as causes dopaminergic neurodegeneration. Therefore, it can be propounded that elevated level of Hcy (hyperhomocysteinemia) is one of the underlying causes of L-DOPA-induced side-effects and aggravates the progressive nature of Parkinson's disease, which has been focused here. We have provided a conjectural discussion on the involvement of Hcy in L-DOPA-induced dyskinesia in Parkinson's disease. CONCLUSION: Hyperhomocysteinemia as a result of prolonged L-DOPA therapy is the emerging cause of L-DOPA-induced behavioral abnormalities and progressive nature of Parkinson's disease. GENERAL SIGNIFICANCE: This review highlights that hyperhomocysteinemia could be a putative contributor of the side-effects of chronic L-DOPA therapy because of its neurotoxic potency.


Asunto(s)
Hiperhomocisteinemia/inducido químicamente , Levodopa/efectos adversos , Levodopa/farmacología , Levodopa/uso terapéutico , Enfermedad de Parkinson/tratamiento farmacológico , Animales , Antiparkinsonianos/efectos adversos , Antiparkinsonianos/uso terapéutico , Conducta Animal/efectos de los fármacos , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Dopamina/metabolismo , Humanos , Enfermedad de Parkinson/metabolismo
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