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1.
Proc Natl Acad Sci U S A ; 120(24): e2216522120, 2023 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-37279274

RESUMO

During infections with the malaria parasites Plasmodium vivax, patients exhibit rhythmic fevers every 48 h. These fever cycles correspond with the time the parasites take to traverse the intraerythrocytic cycle (IEC). In other Plasmodium species that infect either humans or mice, the IEC is likely guided by a parasite-intrinsic clock [Rijo-Ferreiraet al., Science 368, 746-753 (2020); Smith et al., Science 368, 754-759 (2020)], suggesting that intrinsic clock mechanisms may be a fundamental feature of malaria parasites. Moreover, because Plasmodium cycle times are multiples of 24 h, the IECs may be coordinated with the host circadian clock(s). Such coordination could explain the synchronization of the parasite population in the host and enable alignment of IEC and circadian cycle phases. We utilized an ex vivo culture of whole blood from patients infected with P. vivax to examine the dynamics of the host circadian transcriptome and the parasite IEC transcriptome. Transcriptome dynamics revealed that the phases of the host circadian cycle and the parasite IEC are correlated across multiple patients, showing that the cycles are phase coupled. In mouse model systems, host-parasite cycle coupling appears to provide a selective advantage for the parasite. Thus, understanding how host and parasite cycles are coupled in humans could enable antimalarial therapies that disrupt this coupling.


Assuntos
Malária Vivax , Malária , Parasitos , Plasmodium , Humanos , Camundongos , Animais , Interações Hospedeiro-Parasita , Malária/parasitologia , Plasmodium/genética
2.
Am J Ind Med ; 65(1): 30-40, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34706100

RESUMO

BACKGROUND: Mining is a significant economic force in the United States but has historically had among the highest nonfatal injury rates across all industries. Several factors, including workplace hazards and psychosocial stressors, may increase injury and fatality risk. Mining is one of the noisiest industries; however, the association between injury risk and noise exposure has not been evaluated in this industry. In this ecological study, we assessed the association between noise exposure and nonfatal and fatal occupational injury rates among miners. METHODS: Federal US mining accident, injury, and illness data sets from 1983 to 2014 were combined with federal quarterly mining employment and production reports to quantify annual industry rates of nonfatal injuries and fatalities. An existing job-exposure matrix for occupational noise was used to estimate annual industry time-weighted average (TWA, dBA) exposures. Negative binomial models were used to assess relationships between noise, hearing conservation program (HCP) regulation changes in 2000, year, and mine type with incidence rates of injuries and fatalities. RESULTS: Noise, HCP regulation changes, and mine type were each independently associated with nonfatal injuries and fatalities. In multivariate analysis, each doubling (5 dB increase) of TWA was associated with 1.08 (95% confidence interval: 1.05, 1.11) and 1.48 (1.23, 1.78) times higher rate of nonfatal injuries and fatalities, respectively. HCP regulation changes were associated with 0.61 (0.54, 0.70) and 0.49 (0.34, 0.71) times lower nonfatal injury and fatality rates, respectively. CONCLUSION: Noise may be a significant independent risk factor for injuries and fatalities in mining.


Assuntos
Mineradores , Ruído Ocupacional , Traumatismos Ocupacionais , Humanos , Mineração , Ruído Ocupacional/efeitos adversos , Traumatismos Ocupacionais/epidemiologia , Estudos Retrospectivos , Estados Unidos/epidemiologia
3.
J Occup Environ Hyg ; 19(7): 437-447, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35537195

RESUMO

Recently, the National Institute for Occupational Safety and Health (NIOSH) released an updated version of the NIOSH Industry and Occupation Computerized Coding System (NIOCCS), which uses supervised machine learning to assign industry and occupational codes based on provided free-text information. However, no efforts have been made to externally verify the quality of assigned industry and job titles when the algorithm is provided with inputs of varying quality. This study sought to evaluate whether the NIOCCS algorithm was sufficiently robust with low-quality inputs and how variable quality could impact subsequent job estimated exposures in a large job-exposure matrix for noise (NoiseJEM). Using free-text industry and job descriptions from >700,000 noise measurements in the NoiseJEM, three files were created and input into NIOCCS: (1) N1, "raw" industries and job titles; (2) N2, "refined" industries and "raw" job titles; and (3) N3, "refined" industries and job titles. Standardized industry and occupation codes were output by NIOCCS. Descriptive statistics of performance metrics (e.g., misclassification/discordance of occupation codes) were evaluated for each input relative to the original NoiseJEM dataset (N0). Across major Standardized Occupational Classifications (SOC), total discordance rates for N1, N2, and N3 compared to N0 were 53.6%, 42.3%, and 5.0%, respectively. The impact of discordance on the major SOC group varied and included both over- and under-estimates of average noise exposure compared to N0. N2 had the most accurate noise exposure estimates (i.e., smallest bias) across major SOC groups compared to N1 and N3. Further refinement of job titles in N3 showed little improvement. Some variation in classification efficacy was seen over time, particularly prior to 1985. Machine learning algorithms can systematically and consistently classify data but are highly dependent on the quality and amount of input data. The greatest benefit for an end-user may come from cleaning industry information before applying this method for job classification. Our results highlight the need for standardized classification methods that remain constant over time.


Assuntos
Exposição Ocupacional , Algoritmos , Aprendizado de Máquina , National Institute for Occupational Safety and Health, U.S. , Ocupações , Estados Unidos
4.
J Magn Reson Imaging ; 54(5): 1404-1414, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33970520

RESUMO

BACKGROUND: Alterations in glycolysis are central to the increasing incidence of non-alcoholic fatty liver disease (NAFLD), highlighting a need for in vivo, non-invasive technologies to understand the development of hepatic metabolic aberrations. PURPOSE: To use hyperpolarized magnetic resonance spectroscopy (MRS) and proton density fat fraction (PDFF) magnetic resonance imaging (MRI) techniques to investigate the effects of a chronic, life-long exposure to the Western diet (WD) in an animal model resulting in NAFLD; to investigate the hypothesis that exposure to the WD will result in NAFLD in association with altered pyruvate metabolism. STUDY TYPE: Prospective. ANIMAL MODEL: Twenty-eight male guinea pigs weaned onto a control diet (N = 14) or WD (N = 14). FIELD STRENGTH/SEQUENCE: 3 T; T1-weighted gradient echo, T2-weighted spin-echo, three-dimensional gradient multi-echo fat-water separation (IDEAL-IQ), and broadband point-resolved spectroscopy (PRESS) chemical-shift sequences. ASSESSMENT: Median PDFF was calculated in the liver and hind limbs. [1-13 C]pyruvate dynamic MRS in the liver was quantified by the time-to-peak (TTP) for each metabolite. Animals were euthanized and tissue was analyzed for lipid and cholesterol concentration and enzyme level and activity. STATISTICAL TESTS: Unpaired Student's t-tests were used to determine differences in measurements between the two diet groups. The Pearson correlation coefficient was calculated to determine correlations between measurements. RESULTS: Life-long WD consumption resulted in significantly higher liver PDFF and elevated triglyceride content in the liver. The WD group exhibited a decreased TTP for lactate production, and ex vivo analysis highlighted increased liver lactate dehydrogenase (LDH) activity. DATA CONCLUSION: PDFF MRI results suggest differential fat deposition patterns occurring in animals fed a life-long WD characteristic of lean, or lacking excessive subcutaneous fat, NAFLD. The decreased liver lactate TTP and increased ex vivo LDH activity suggest lipid accumulation occurs in association with a shift from oxidative metabolism to anaerobic glycolytic metabolism in WD-exposed livers. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY STAGE: 1.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Animais , Dieta Ocidental , Cobaias , Fígado/diagnóstico por imagem , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Masculino , Hepatopatia Gordurosa não Alcoólica/diagnóstico por imagem , Estudos Prospectivos , Prótons , Ácido Pirúvico , Reprodutibilidade dos Testes
5.
Occup Environ Med ; 2021 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-33436381

RESUMO

OBJECTIVE: This study investigated risk factors for poor earplug fit, with a focus on the association between hearing loss and personal attenuation ratings (PARs). METHODS: Earplug fit was assessed by obtaining PARs using a real ear at attenuation threshold (REAT) system. Hearing loss was assessed using the unoccluded hearing thresholds measured during the REAT testing and the results of a speech-in-noise test. Potential predictors of PARs were modelled using both simple and multiple linear regression. Hearing loss was the primary predictor of interest. RESULTS: Data were collected from 200 workers at ten above-ground mining sites in the Midwestern USA. Workers reported wearing their hearing protection on average 73.9% of the time in a high noise environment (mean 8-hour time-weighted average noise exposure 85.5 dBA, range 65-103 dBA). One-quarter (26.7%) of workers were found to have a hearing loss (hearing threshold ≥25 dB across 1-4 kHz), and 42% reported symptoms of tinnitus. Workers with a hearing loss had a significantly lower PAR than those without a hearing loss (ß=-5.1, SE=1.7). CONCLUSIONS: The results of the adjusted regression models suggest that workers with hearing loss achieved significantly lower PARs than those without hearing loss. This association between hearing loss and hearing protection devices (HPD) fit brings into focus the potential benefit of fit checks to be included in hearing conservation programmes. Workers found to have hearing loss should be prioritised for fit testing, as their hearing impairment may be associated with poor HPD fit.

6.
Magn Reson Med ; 84(3): 1510-1517, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32011018

RESUMO

PURPOSE: To improve the SNR of hyperpolarized carbon-13 MRI of [1-13 C]pyruvate using a multispectral variable flip angle (msVFA) scheme in which the spectral profile and flip angle vary dynamically with time. METHODS: Each image acquisition in a time-resolved imaging experiment used a unique spectrally varying RF pulse shape for msVFA. Therefore, the flip angle for every acquisition was optimized for pyruvate and each of its metabolites to yield the highest SNR across the acquisition. Multispectral VFA was compared with a spectrally varying constant flip-angle excitation model through simulations and in vivo. A modified broadband chemical shift-encoded gradient-echo sequence was used for in vivo experiments on six pregnant guinea pigs. Regions of interest placed in the placentae, maternal liver, and maternal kidneys were used as areas for SNR measurement. RESULTS: In vivo experiments showed significant increases in SNR for msVFA relative to constant flip angle of up to 250% for multiple metabolites. CONCLUSION: Hyperpolarized carbon-13 imaging with msVFA excitation produces improved SNR for all metabolites in organs of interest.


Assuntos
Imageamento por Ressonância Magnética , Ácido Pirúvico , Algoritmos , Animais , Isótopos de Carbono , Feminino , Cobaias , Fígado/diagnóstico por imagem , Gravidez
7.
J Math Biol ; 80(5): 1523-1557, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32008103

RESUMO

Experimental time series provide an informative window into the underlying dynamical system, and the timing of the extrema of a time series (or its derivative) contains information about its structure. However, the time series often contain significant measurement errors. We describe a method for characterizing a time series for any assumed level of measurement error [Formula: see text] by a sequence of intervals, each of which is guaranteed to contain an extremum for any function that [Formula: see text]-approximates the time series. Based on the merge tree of a continuous function, we define a new object called the normalized branch decomposition, which allows us to compute intervals for any level [Formula: see text]. We show that there is a well-defined total order on these intervals for a single time series, and that it is naturally extended to a partial order across a collection of time series comprising a dataset. We use the order of the extracted intervals in two applications. First, the partial order describing a single dataset can be used to pattern match against switching model output (Cummins et al. in SIAM J Appl Dyn Syst 17(2):1589-1616, 2018), which allows the rejection of a network model. Second, the comparison between graph distances of the partial orders of different datasets can be used to quantify similarity between biological replicates.


Assuntos
Modelos Biológicos , Algoritmos , Causalidade , Ciclo Celular/genética , Biologia Computacional , Bases de Dados Factuais/estatística & dados numéricos , Redes Reguladoras de Genes , Análise de Séries Temporais Interrompida/estatística & dados numéricos , Modelos Lineares , Conceitos Matemáticos , Modelos Genéticos , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/genética , Razão Sinal-Ruído , Fatores de Tempo
8.
Curr Opin Anaesthesiol ; 33(1): 64-70, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31833864

RESUMO

PURPOSE OF REVIEW: Regional anesthesia blocks may benefit patients undergoing cardiovascular surgery. This review coincides with the evolution of ultrasound-guided fascial plane blocks, societal concerns regarding opioid misuse and changing expectations regarding surgical recovery. RECENT FINDINGS: Paravertebral block and thoracic epidural analgesia have comparable postoperative analgesic profiles following thoracotomy; however, the former has a more favorable complication profile. Limited trials have compared these modalities in cardiac surgery. The mechanism of action of continuous paravertebral blockade may be systemic. Bilateral continuous paravertebral (and other continuous peripheral nerve blocks) should be used with caution in adult patients having cardiac surgery because of the risk of systemic local anesthetic toxicity and bleeding. Novel ultrasound-guided blocks: erector spinae, serratus anterior, pectoral, transversus thoracic muscle and pecto-intercostal fascial plane blocks potentially reduce postoperative opioid requirements; however, they require further investigation before their routine use can be recommended in adult cardiovascular surgical practice. The mechanism of action of erector spinae block is not fully elucidated. SUMMARY: Ultrasound-guided fascial plane blocks may reduce postoperative opioid requirements. Investigation into the safety and efficacy of bilateral continuous ultrasound-guided blockade for cardiac surgery is required. Trial protocols should be embedded into enhanced recovery after surgery programs. Patient-reported and long-term outcomes are recommended.


Assuntos
Anestesia por Condução , Anestesia Epidural , Procedimentos Cirúrgicos Cardiovasculares , Bloqueio Nervoso , Ultrassonografia de Intervenção , Adulto , Humanos , Bloqueio Nervoso/métodos , Dor Pós-Operatória , Toracotomia
9.
Anesth Analg ; 125(6): 1931-1945, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28537970

RESUMO

Neuraxial anesthesia may improve perioperative outcomes when compared to general anesthesia; however, this is controversial. We performed a systematic review and meta-analysis using randomized controlled trials and population-based observational studies identified in MEDLINE, PubMed, and EMBASE from 2010 to May 31, 2016. Studies were included for adult patients undergoing major surgery of the trunk and lower extremity that reported: 30-day mortality (primary outcome), cardiopulmonary morbidity, surgical site infection, thromboembolic events, blood transfusion, and resource use. Perioperative outcomes were compared with general anesthesia for the following subgroups: combined neuraxial-general anesthesia and neuraxial anesthesia alone. Odds ratios (ORs) and 99% confidence intervals (CIs) were calculated to identify the impact of anesthetic technique on outcomes. Twenty-seven observational studies and 11 randomized control trials were identified. This analysis comprises 1,082,965 records from observational studies or databases and 1134 patients from randomized controlled trials. There was no difference in 30-day mortality identified when combined neuraxial-general anesthesia was compared with general anesthesia (OR 0.88; 99% CI, 0.77-1.01), or when neuraxial anesthesia was compared with general anesthesia (OR 0.98; 99% CI, 0.92-1.04). When combined neuraxial-general anesthesia was compared with general anesthesia, combined neuraxial-general anesthesia was associated with a reduced odds of pulmonary complication (OR 0.84; 99% CI, 0.79-0.88), surgical site infection (OR 0.93; 99% CI, 0.88-0.98), blood transfusion (OR 0.90; 99% CI, 0.87-0.93), thromboembolic events (OR 0.84; 99% CI, 0.73-0.98), length of stay (mean difference -0.16 days; 99% CI, -0.17 to -0.15), and intensive care unit admission (OR 0.77; 99% CI, 0.73-0.81). For the combined neuraxial-general anesthesia subgroup, there were increased odds of myocardial infarction (OR 1.18; 99% CI, 1.01-1.37). There was no difference identified in the odds of pneumonia (OR 0.94; 99% CI, 0.87-1.02) or cardiac complications (OR 1.04; 99% CI, 1.00-1.09) for the combined neuraxial-general anesthesia subgroup. When neuraxial anesthesia was compared to general anesthesia, there was a decreased odds of any pulmonary complication (OR 0.38; 99% CI, 0.36-0.40), surgical site infection (OR 0.76; 99% CI, 0.71-0.82), blood transfusion (OR 0.85; 99% CI, 0.82-0.88), thromboembolic events (OR 0.79; 99% CI, 0.68-0.91), length of stay (mean difference -0.29 days; 99% CI, -0.29 to -0.28), and intensive care unit admission (OR 0.50; 99% CI, 0.48-0.53). There was no difference in the odds of cardiac complications (OR 0.99; 99% CI, 0.94-1.03), myocardial infarction (OR 0.91; 99% CI, 0.81-1.02), or pneumonia (OR 0.92; 99% CI, 0.84-1.01). Randomized control trials revealed no difference in requirement for blood transfusion (RR 1.05; 99% CI, 0.65-1.71) and a decreased length of stay (mean difference -0.15 days; 99% CI, -0.27 to -0.04). Neuraxial anesthesia when combined with general anesthesia or when used alone was not associated with decreased 30-day mortality. Neuraxial anesthesia may improve pulmonary outcomes and reduce resource use when compared with general anesthesia. However, because observational studies were included in this analysis, there is a risk of residual confounding and therefore these results should be interpreted with caution.


Assuntos
Anestesia Epidural/mortalidade , Anestesia Geral/mortalidade , Raquianestesia/mortalidade , Extremidade Inferior/cirurgia , Complicações Pós-Operatórias/mortalidade , Anestesia por Condução/efeitos adversos , Anestesia por Condução/mortalidade , Anestesia Epidural/efeitos adversos , Anestesia Geral/efeitos adversos , Raquianestesia/efeitos adversos , Humanos , Mortalidade/tendências , Estudos Observacionais como Assunto/métodos , Complicações Pós-Operatórias/etiologia , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Infecção da Ferida Cirúrgica/etiologia , Infecção da Ferida Cirúrgica/mortalidade
10.
Ecology ; 96(9): 2523-32, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26594708

RESUMO

Net pairwise plant-soil feedbacks (PSF) may be an important factor structuring plant communities, yet the influence of abiotic context on PSF is not yet understood. Abiotic factors such as light availability can alter plant-soil interactions, potentially resulting in strong context dependence of PSF. Here, we present an experiment in which we measured whole-soil net pairwise feedbacks amongst six common forest understory species across a gradient of light availability. Light treatments were imposed throughout both phases (the conditioning phase and the response phase) of the feedback experiment. Across the plant community, PSF shifted from negative at high light availability to weakly positive under low light (P = 0.0 13). Differences in the biomass of plants during the conditioning phase did not fully explain light-imposed differences in feedbacks, indicating that reduced light availability qualitatively changes the nature of PSF rather than simply weakening feedbacks by reducing plant growth. Results indicate that abiotic context can fundamentally alter the role of PSF in structuring plant communities.


Assuntos
Florestas , Luz , Plantas/metabolismo , Solo/química , Biomassa , Desenvolvimento Vegetal , Plantas/química , Especificidade da Espécie
11.
Connect Tissue Res ; 56(2): 106-19, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25646568

RESUMO

Advances in computed tomography (CT) imaging are opening new avenues toward more precise characterization and quantification of connective tissue microarchitecture. In the last two decades, micro-computed tomography (microCT) has significantly augmented destructive methods for the 3D micro-analysis of tissue structure, primarily in the bone research field. Recently, microCT has been employed in combination with contrast agents to generate contrast-enhanced images of soft tissues that are otherwise difficult to visualize due to their native radiodensity. More recent advances in CT technology have enabled ultra-high resolution imaging by utilizing a more powerful nano-focused X-ray source, such as that found in nano-computed tomography (nanoCT) systems. NanoCT imaging has facilitated the expansion of musculoskeletal research by reducing acquisition time and significantly expanding the range of samples that can be imaged in terms of size, age and tissue-type (bone, muscle, tendon, cartilage, vessels and adipose tissue). We present the application and early results of nanoCT imaging in various tissue types and how this ultra-high resolution imaging modality is capable of characterizing microstructures at levels of details previously not possible. Contrast-enhanced imaging techniques to enable soft-tissue visualization and characterization are also outlined.


Assuntos
Osso e Ossos/citologia , Processamento de Imagem Assistida por Computador , Microtomografia por Raio-X , Animais , Cartilagem , Tecido Conjuntivo , Humanos , Imageamento Tridimensional/métodos
12.
J Chem Ecol ; 41(5): 486-92, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25912227

RESUMO

Garlic mustard is a well-known invader of deciduous forests of North America, yet the influence of environmental factors on garlic mustard allelochemical production is not well understood. Three experiments were conducted to detect interactions between one garlic mustard allelochemical (glucosinolate) production and light availability. First, to detect patterns of glucosinolate production across a natural light gradient, leaves and roots of mature plants and first-year rosettes were sampled in patches ranging from 100 to 2 % of full sun within an Indiana forest. Second, to determine whether genetic variation drives observed correlations between glucosinolate content and light, seed collected across light gradients within six sites was grown in a common garden and glucosinolate production was measured. Finally, to understand whether local adaptation occurred in garlic mustard's response to light, seed collected from defined light environments across six sites was grown under four light treatments. Results of the field sampling showed that mature plants' root glucosinolate content was elevated in high compared to low light. In the common garden experiment, however, there was no correlation between light availability at seed origin and constitutive glucosinolate content. Additionally, in the common light treatments, there was no evidence for local adaptation to light environment. Overall, the results indicate that plasticity in response to light, not genetic variation among plants growing in different light environments, generates correlations between glucosinolate content and light in the field. Since mature garlic mustard populations in high light may exhibit increased glucosinolate content, it makes them potential targets for management.


Assuntos
Brassicaceae/efeitos da radiação , Glucosinolatos/metabolismo , Feromônios/metabolismo , Adaptação Biológica , Brassicaceae/metabolismo , Espécies Introduzidas , Luz Solar
13.
J Infect Dis ; 208(2): 310-8, 2013 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-23255566

RESUMO

There is a clear need for novel, effective therapeutic approaches to hemorrhagic fever due to filoviruses. Ebola virus hemorrhagic fever is associated with robust interferon (IFN)-α production, with plasma concentrations of IFN-α that greatly (60- to 100-fold) exceed those seen in other viral infections, but little IFN-ß production. While all of the type I IFNs signal through the same receptor complex, both quantitative and qualitative differences in biological activity are observed after stimulation of the receptor complex with different type I IFNs. Taken together, this suggested potential for IFN-ß therapy in filovirus infection. Here we show that early postexposure treatment with IFN-ß significantly increased survival time of rhesus macaques infected with a lethal dose of Ebola virus, although it failed to alter mortality. Early treatment with IFN-ß also significantly increased survival time after Marburg virus infection. IFN-ß may have promise as an adjunctive postexposure therapy in filovirus infection.


Assuntos
Doença pelo Vírus Ebola/tratamento farmacológico , Interferon beta/farmacologia , Doença do Vírus de Marburg/tratamento farmacológico , Marburgvirus/efeitos dos fármacos , Animais , Ebolavirus/efeitos dos fármacos , Feminino , Doença pelo Vírus Ebola/virologia , Humanos , Macaca mulatta , Masculino , Doença do Vírus de Marburg/virologia , Proteínas Recombinantes/farmacologia
14.
Semin Radiat Oncol ; 34(1): 56-63, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38105094

RESUMO

The landscape of lung radiotherapy (RT) has rapidly evolved over the past decade with modern RT and surgical techniques, systemic therapies, and expanding indications for RT. To date, 2 MRI-guided RT (MRgRT) units, 1 using a 0.35T magnet and 1 using a 1.5T magnet, are available for commercial use with more systems in the pipeline. MRgRT offers distinct advantages such as real-time target tracking, margin reduction, and on-table treatment adaptation, which may help overcome many of the common challenges associated with thoracic RT. Nonetheless, the use of MRI for image guidance and the current MRgRT units also have intrinsic limitations. In this review article, we will discuss clinical experiences to date, advantages, challenges, and future directions of MRgRT to the lung.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Radioterapia (Especialidade) , Radioterapia Guiada por Imagem , Humanos , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/radioterapia , Radioterapia Guiada por Imagem/métodos , Imageamento por Ressonância Magnética/métodos
15.
Dev Cogn Neurosci ; 64: 101325, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37972500

RESUMO

Joint attention (JA) is an early-developing behavior that allows caregivers and infants to share focus on an object. Deficits in JA, as measured through face-following pathways, are a defining feature of autism spectrum disorder (ASD) and are observable as early as 12 months of age in infants later diagnosed with ASD. However, recent evidence suggests that JA may be achieved through hand-following pathways by children with and without ASD. Development of JA through multimodal pathways has yet to be studied in infants with an increased likelihood of developing ASD. The current study investigated how 6-, 9- and 12-month-old infants with (FH+) and without (FH-) a family history of ASD engaged in JA. Parent-infant dyads played at home while we recorded the interaction over Zoom and later offline coded for hand movements and gaze. FH+ and FH- infants spent similar amounts of time in JA with their parents, but the cues available before JA were different. Parents of FH+ infants did more work to establish JA and used more face-following than hand-following pathways compared to parents of FH- infants, likely reflecting differences in infant motor or social behavior. These results suggest that early motor differences between FH+ and FH- infants may cascade into differences in social coordination.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Lactente , Criança , Humanos , Transtorno do Espectro Autista/diagnóstico , Comportamento Social , Pais , Atenção
16.
Int J Hyg Environ Health ; 254: 114263, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37742520

RESUMO

While perceptions of risk have been examined in the workplace to understand safety behavior, hazard perception has been overlooked, particularly for chemical, physical, and biological agents. This study sought to establish the prevalence of one type of mismatch in hazard perception, - noise misperception - among miners, to examine whether different types of noisy environments (e.g., continuous, highly variable, etc.) alter workers' misperception of their noise exposures, and to evaluate whether noise misperception is associated with hearing protection device (HPD) use behavior. In this cross-sectional study across 10 surface mines in the USA, 135 normal-hearing participants were surveyed on their perceptions of exposure to noise at work and were monitored for three shifts, each with personal noise dosimetry, to examine which workers had a mismatch in perceived versus true noise exposure by 8-hr, time-weighted average, NIOSH exposure limits (TWANIOSH). Mixed effects logistic regression and probit Bayesian Kernel Machine Regression (BKMR) models examining on the odds of noise misperception associated with four different noise metrics (kurtosis, crest factor, variability, and number of peaks >135 dB) were used to determine which types of noisy environments may influence noise misperception. The relationship between noise misperception and odds of not wearing HPDs during a work shift was further examined. Our findings showed that nearly 1 in 3 workers underestimated their exposure to noise when their true exposure was in fact hazardous (TWANIOSH≥85 dBA) for at least one shift, and 6% misperceived hazardous exposures for all shifts. Work shifts with highly kurtotic noise distributions (>3) had 3.1 (95% CI: 1.1 to 8.4) times significantly higher odds of resulting in misperceived noise; no other noise metric was significantly associated with noise misperception. BKMR modeling provided further evidence that kurtosis dominates this relationship, with an IQR increase in kurtosis significantly associated with 1.68 (95% CI: 1.13 to 2.50) higher odds of noise misperception. Although not statistically significant, misperception of hazardous noise exposure was associated with 3.2 (95% CI: 0.8 to 12.5) times higher odds of not using earplugs during a work shift. Misperception of noise occurs in the workplace, and likely occurs for other physical, chemical, and biological exposures. This hazard misperception may influence risk perceptions and worker behavior and reduce the effectiveness of behavior-related training. Elimination, substitution, or engineering controls of exposures is the best way to prevent hazard misperceptions and exposure-related diseases.


Assuntos
Ruído Ocupacional , Exposição Ocupacional , Humanos , Estudos Transversais , Teorema de Bayes , Exposição Ocupacional/prevenção & controle , Percepção
17.
Radiother Oncol ; 183: 109631, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36934894

RESUMO

BACKGROUND AND PURPOSE: We examined the interfractional variations of clinical target volumes (CTVs), planning target volumes (PTVs), and organs-at-risk (OARs) in patients receiving MRI-guided stereotactic body radiotherapy (SBRT) to the prostate bed and evaluated the potential role of adaptive planning. MATERIALS AND METHODS: 31 patients received 30-34 Gy in five fractions to the prostate bed on a phase II clinical trial. OARs, CTVs, and PTVs were retrospectively contoured on daily pretreatment MRIs (n = 155). Geometric comparisons were made between initial planning contours and daily pretreatment contours. Predicted treatment plans for each fraction were evaluated using the following constraints: CTV V95%>93%, PTV V95%>90%, bladder Dmax < 36.7 Gy, bladder V32.5 Gy < 35%, rectum Dmax < 36.7 Gy, rectum V27.5 Gy < 45%, rectum 32.5 Gy < 30%, and rectal wall V24Gy < 50%. Adaptive planning was simulated for all fractions that failed to meet these criteria. Plans were then re-evaluated. RESULTS: Median change in volume was 0.48% for CTV, -24.5% for bladder, and 6.95% for rectum. Median DSC was 0.89 for CTV, 0.79 for bladder, and 0.76 for rectum. 145/155 fractions (93.5%) met CTV V95%>93%. 75/155 fractions (48.4%) failed at least one OAR dose constraint. Overall, 83/155 fractions (53.5%) met criteria for adapting planning. This affected 24/31 patients (77.4%). Following adaptive planning, all fractions met CTV V95%>93% and PTV V95%>90% and 120/155 fractions (77.4%) met all OAR constraints. CONCLUSION: Due to significant interfractional variations in anatomy, a majority of fractions failed to meet both target volume and OAR constraints. However, adaptive planning was effective in overcoming these anatomic changes. Adaptive planning should be routinely considered in prostate bed SBRT.


Assuntos
Neoplasias da Próstata , Radiocirurgia , Radioterapia Guiada por Imagem , Radioterapia de Intensidade Modulada , Masculino , Humanos , Próstata , Estudos Retrospectivos , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Prostatectomia , Imageamento por Ressonância Magnética , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/radioterapia , Neoplasias da Próstata/cirurgia , Órgãos em Risco
18.
J Cancer Educ ; 27(1 Suppl): S91-105, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22351428

RESUMO

The cost of smoking has been explored for residents of the U.S. living in several states. Recent evidence has indicated that the prevalence and cost of smoking are associated with racial and ethnic groups. This study provides information on tobacco prevention and control for American Indians (AI) (American Indians refers to American Indians and Alaska Natives throughout this article. Where we use the term California tribe we specifically mean persons who are members of Indigenous tribes geographically located in the geographic area now known as the state of California.) and examines the relative impact of smoking by using behavioral and demographic characteristics in order to predict the economic cost on AIs. The analysis suggests that AIs smoke more frequently than other Californians, which results in higher health care costs, as well as morbidity and mortality due to high levels of tobacco related chronic disease. Based on these factors we urge tribes to exercise their sovereignty as governments and implement local tobacco control policy strategies. We call for public health action by community leaders in Indian country and nationwide. We must act now to protect future generations.


Assuntos
Serviços de Saúde Comunitária/economia , Custos de Cuidados de Saúde/estatística & dados numéricos , Política de Saúde/economia , Indígenas Norte-Americanos/estatística & dados numéricos , Abandono do Hábito de Fumar/economia , Fumar/economia , Adulto , Fatores Etários , California/epidemiologia , Serviços de Saúde Comunitária/estatística & dados numéricos , Feminino , Promoção da Saúde/economia , Promoção da Saúde/métodos , Nível de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Saúde das Minorias/economia , Saúde das Minorias/estatística & dados numéricos , Prevalência , Fatores de Risco , Assunção de Riscos , Fumar/epidemiologia , Prevenção do Hábito de Fumar , Acidente Vascular Cerebral , Estados Unidos/epidemiologia
19.
Artigo em Inglês | MEDLINE | ID: mdl-36544051

RESUMO

OBJECTIVES: To identify the most pervasive environmental exposures driving environmental disparities today associated with historical redlining in Detroit. METHODS: We overlaid Detroit's 1939 Home Owners' Loan Corporation (HOLC) shapefile from the Mapping Inequality project onto the EPA EJScreen and the DOT National Transportation Noise maps to analyze differences in current demographic and environmental indicators between historically redlined (D-grade) and non-redlined neighborhoods using simple linear regression and a boosted classification tree algorithm. RESULTS: Historically redlined neighborhoods in Detroit experienced significantly higher environmental hazards than non-redlined neighborhoods in the form of 12.1% (95% CI: 7.2-17.1%) higher levels of diesel particulate matter (PM), 32.2% (95% CI: 3.3-69.3%) larger traffic volumes, and 65.7% (95% CI: 8.6-152.8%) higher exposure to hazardous road noise (LEQ(24h) >70 dBA). Historically redlined neighborhoods were situated near 1.7-times (95% CI: 1.4-2.1) more hazardous waste sites and twice as many (95% CI: 1.5-2.7) risk management plan (RMP) sites than non-redlined neighborhoods. The lifetime cancer risk from inhalation of air toxics was 4.4% (95% CI: 2.9-6.6%) higher in historically redlined communities, and the risk of adverse respiratory health outcomes from air toxics was 3.9% (95% CI: 2.1-5.6%) higher. All factors considered together, among the environmental hazards considered, the most pervasive hazards in historically redlined communities are proximity to RMP sites, hazardous road noise, diesel PM, and cancer risk from air pollution. CONCLUSIONS: Historically redlined neighborhoods may have a disproportionately higher risk of developing cancer and adverse respiratory health outcomes from air toxics. Policies targeting air and noise pollution from transportation sources, particularly from sources of diesel exhaust, in historically redlined neighborhoods may ameliorate some of the impacts of structural environmental racism from historical redlining in Detroit.

20.
Appl Ergon ; 103: 103772, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35500524

RESUMO

This study examined associations between metrics of noise exposure and mental workload. In this cross-sectional study, five occupational noise metrics computed from full-shift dosimetry were evaluated among surface mine workers in the US Midwest. Mental workload was evaluated using a modified, raw NASA-TLX and clustered with a k-means clustering algorithm. Mixed effects logistic regression and Bayesian Kernel Machine Regression (BKMR) was utilized for analysis. Average noise exposure, the difference between peak and mean noise exposure, and the number of peaks >135 dB were each strongly associated with mental workload, while the kurtosis and standard deviation of noise throughout a shift were not. An exposure-response relationship between average noise exposure and mental workload may exist, with elevated risk of high mental workload beginning at 80 dBA. These results suggest that high noise exposure may be an independent risk factor of high mental workload, and impulse events and the difference between the peak and mean noise exposure may have interactive effects with average noise exposure.


Assuntos
Mineradores , Ruído Ocupacional , Teorema de Bayes , Benchmarking , Estudos Transversais , Humanos , Ruído Ocupacional/efeitos adversos , Carga de Trabalho
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