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1.
Breast Cancer Res Treat ; 205(2): 323-332, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38433127

RESUMO

PURPOSE: Female breast cancer (BC) is the leading cause of cancer incidence and mortality in India, and accounted for 13.5% of new cancer cases and 10% of cancer-related deaths in 2020. This study aims to estimate and report the female BC burden in India at state level from 2012 to 2016 in terms of years of life lost, years lived with disability, and disability-adjusted life years (DALYs), and to project the burden for the year 2025. METHODS: The cancer incidence and mortality data from 28 population-based cancer registries were analysed. The mean mortality to incidence ratio was estimated, and mortality figures were adjusted for underreporting. The burden of female BC was estimated at national and subnational levels using Census data, World Health Organisation's lifetables, disability weights, and the DisMod-II tool. A negative binomial regression is employed to project burden for 2025. RESULTS: The burden of BC among Indian women in 2016 was estimated to be 515.4 DALYs per 100,000 women after age standardization. The burden metrics at state level exhibited substantial heterogeneity. Notably, Tamil Nadu, Telangana, Karnataka, and Delhi had a higher burden of BC than states in the eastern and north-eastern regions. The projection for 2025 indicates to a substantial increase, reaching 5.6 million DALYs. CONCLUSION: The female BC burden in India was significantly high in 2016 and is expected to substantially increase. Undertaking a multidisciplinary, context-specific approach for its prevention and control can address this rising burden.


Assuntos
Neoplasias da Mama , Efeitos Psicossociais da Doença , Sistema de Registros , Humanos , Feminino , Índia/epidemiologia , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/mortalidade , Pessoa de Meia-Idade , Incidência , Adulto , Idoso , Anos de Vida Ajustados por Deficiência , Anos de Vida Ajustados por Qualidade de Vida , Adulto Jovem , Idoso de 80 Anos ou mais
2.
Arterioscler Thromb Vasc Biol ; 43(6): 958-970, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37078284

RESUMO

BACKGROUND: Cerebral cavernous malformations, also known as cavernous angiomas, are blood vessel abnormalities comprised of clusters of grossly enlarged and hemorrhage-prone capillaries. The prevalence in the general population, including asymptomatic cases, is estimated to be 0.5%. Some patients develop severe symptoms, including seizures and focal neurological deficits, whereas others remain asymptomatic. The causes of this remarkable presentation heterogeneity within a primarily monogenic disease remain poorly understood. METHODS: We established a chronic mouse model of cerebral cavernous malformations, induced by postnatal ablation of Krit1 with Pdgfb-CreERT2, and examined lesion progression in these mice with T2-weighted 7T magnetic resonance imaging (MRI). We also established a modified protocol for dynamic contrast-enhanced MRI and produced quantitative maps of gadolinium tracer gadobenate dimeglumine. After terminal imaging, brain slices were stained with antibodies against microglia, astrocytes, and endothelial cells. RESULTS: These mice develop cerebral cavernous malformations lesions gradually over 4 to 5 months of age throughout the brain. Precise volumetric analysis of individual lesions revealed nonmonotonous behavior, with some lesions temporarily growing smaller. However, the cumulative lesional volume invariably increased over time and after about 2 months followed a power trend. Using dynamic contrast-enhanced MRI, we produced quantitative maps of gadolinium in the lesions, indicating a high degree of heterogeneity in lesional permeability. MRI properties of the lesions were correlated with cellular markers for endothelial cells, astrocytes, and microglia. Multivariate comparisons of MRI properties of the lesions with cellular markers for endothelial and glial cells revealed that increased cell density surrounding lesions correlates with stability, whereas denser vasculature within and surrounding the lesions may correlate with high permeability. CONCLUSIONS: Our results lay a foundation for better understanding individual lesion properties and provide a comprehensive preclinical platform for testing new drug and gene therapies for controlling cerebral cavernous malformations.


Assuntos
Hemangioma Cavernoso do Sistema Nervoso Central , Humanos , Camundongos , Animais , Hemangioma Cavernoso do Sistema Nervoso Central/diagnóstico por imagem , Hemangioma Cavernoso do Sistema Nervoso Central/genética , Hemangioma Cavernoso do Sistema Nervoso Central/patologia , Gadolínio , Células Endoteliais/patologia , Encéfalo/patologia , Imageamento por Ressonância Magnética
3.
J Nematol ; 56(1): 20240006, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38510970

RESUMO

Control of plant-parasitic nematodes (PPNs) on golf putting greens with nematicides is dependent on the seasonal occurrence and depth distribution of target PPN populations. This study aimed to determine if plant-parasitic nematode populations on golf course putting greens in Missouri and Indiana peaked at a targetable depth at a specific time in the year, focusing primarily on lance (Hoplolaimus spp.) and root-knot (Meloidogyne spp.) nematodes. To elucidate species diversity in the region, rDNA from a subset of lance and root-knot nematodes was sequenced and analyzed, with additional micromorphology of a lance nematode assessed in scanning electron micrographs (SEM). Soil samples were taken to a depth of 25 cm and stratified into 5 cm increments during April, June, August and October at seven sites across Missouri, three in the Kansas City metro of Kansas in 2021 and in ten sites across Indiana in 2022. Samples were stratified in five-centimeter increments and aggregated for a total of 100 cm3 of soil at each depth for each sampling. Samples were processed using a semi-automatic elutriator followed by the sucrose-flotation method, and populations were counted using a hemocytometer and recorded. For molecular characterization, rDNA was extracted and analyzed from 31 individual lance nematodes from one site in Missouri and eight sites in Indiana, and 13 root-knot nematodes from nine sites across Indiana. A significant interaction occurred between sampling month and depth for lance and ring nematodes Missouri/KS, with both PPN populations peaking at the 0-5 cm depth during October, which is well after most targeted nematicide applications are applied. Ring nematodes in Indiana did not follow this trend and were most abundant in August at a depth of 0-5 cm. No significant interaction between depth and month occurred for lance or root-knot nematodes in Indiana, or root-knot nematodes in Missouri/KS. Hoplolaimus stephanus and H. magnistylus were the lance species identified on golf greens, and Meloidogyne naasi, M. graminicola and M. marylandi were the root-knot species identified. Scanning-electron micrographs confirmed morphological characteristics unique to H. stephanus.

4.
Magn Reson Med ; 89(6): 2255-2263, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36669874

RESUMO

PURPOSE: To develop and test compressed sensing-based multiframe 3D MRI of grid-tagged hyperpolarized gas in the lung. THEORY AND METHODS: Applying grid-tagging RF pulses to inhaled hyperpolarized gas results in images in which signal intensity is predictably and sparsely distributed. In the present work, this phenomenon was used to produce a sampling pattern in which k-space is undersampled by a factor of approximately seven, yet regions of high k-space energy remain densely sampled. Three healthy subjects received multiframe 3D 3 He tagging MRI using this undersampling method. Images were collected during a single exhalation at eight timepoints spanning the breathing cycle from end-of-inhalation to end-of-exhalation. Grid-tagged images were used to generate 3D displacement maps of the lung during exhalation, and time-resolved maps of principal strains and fractional volume change were generated from these displacement maps using finite-element analysis. RESULTS: Tags remained clearly resolvable for 4-6 timepoints (5-8 s) in each subject. Displacement maps revealed noteworthy temporal and spatial nonlinearities in lung motion during exhalation. Compressive normal strains occurred along all three principal directions but were primarily oriented in the head-foot direction. Fractional volume changes displayed clear bilateral symmetry, but with the lower lobes displaying slightly higher change than the upper lobes in 2 of the 3 subjects. CONCLUSION: We developed a compressed sensing-based method for multiframe 3D MRI of grid-tagged hyperpolarized gas in the lung during exhalation. This method successfully overcomes previous challenges for 3D dynamic grid-tagging, allowing time-resolved biomechanical readouts of lung function to be generated.


Assuntos
Compressão de Dados , Pulmão , Masculino , Humanos , Pulmão/diagnóstico por imagem , Respiração , Imageamento por Ressonância Magnética/métodos
5.
Value Health ; 26(2): 226-233, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36114087

RESUMO

OBJECTIVES: This study aimed to estimate the impact of sharing drug rebates at the point of sale on out-of-pocket spending by linking estimated rebates to administrative claims data for employer-sponsored insurance enrollees in 2018. METHODS: We applied the drug rebate rate to the retail price of each brand name drug fill, allocated the reductions to out-of-pocket spending based on cost-sharing provisions, and aggregated each individual's out-of-pocket spending across drug fills. We assumed that generic drugs have no rebates for employer-sponsored insurance. We assessed the impact of sharing rebates at the point of sale on out-of-pocket spending overall, for the therapeutic classes and specific drugs with the highest average out-of-pocket spending per user, and by health plan type. RESULTS: Across 4 simulations with different assumptions about the degree of cross-fill effects, we found that 10.4% to 12.2% of enrollees in our sample would have realized savings on out-of-pocket spending if rebates were shared to the point of sale. Among those with savings, approximately half would save $50 or less, and 10% would save > $500 annually. We calculated that a premium increase of $1.06 to $1.41 per member per month among the continuously enrolled, insured population would be sufficient to finance the out-of-pocket savings in our sample. CONCLUSIONS: Our study suggests that, for a small percentage of enrollees, sharing drug rebates at the point of sale would likely improve the affordability of high-priced brand name drugs, especially drugs that face significant competition.


Assuntos
Custo Compartilhado de Seguro , Gastos em Saúde , Humanos , Estados Unidos
6.
Proc Natl Acad Sci U S A ; 117(11): 5644-5654, 2020 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-32123081

RESUMO

Treatment of many pathologies of the brain could be improved markedly by the development of noninvasive therapeutic approaches that elicit robust, endothelial cell-selective gene expression in specific brain regions that are targeted under MR image guidance. While focused ultrasound (FUS) in conjunction with gas-filled microbubbles (MBs) has emerged as a noninvasive modality for MR image-guided gene delivery to the brain, it has been used exclusively to transiently disrupt the blood-brain barrier (BBB), which may induce a sterile inflammation response. Here, we introduce an MR image-guided FUS method that elicits endothelial-selective transfection of the cerebral vasculature (i.e., "sonoselective" transfection), without opening the BBB. We first determined that activating circulating, cationic plasmid-bearing MBs with pulsed low-pressure (0.1 MPa) 1.1-MHz FUS facilitates sonoselective gene delivery to the endothelium without MRI-detectable disruption of the BBB. The degree of endothelial selectivity varied inversely with the FUS pressure, with higher pressures (i.e., 0.3-MPa and 0.4-MPa FUS) consistently inducing BBB opening and extravascular transfection. Bulk RNA sequencing analyses revealed that the sonoselective low-pressure regimen does not up-regulate inflammatory or immune responses. Single-cell RNA sequencing indicated that the transcriptome of sonoselectively transfected brain endothelium was unaffected by the treatment. The approach developed here permits targeted gene delivery to blood vessels and could be used to promote angiogenesis, release endothelial cell-secreted factors to stimulate nerve regrowth, or recruit neural stem cells.


Assuntos
Barreira Hematoencefálica/metabolismo , Transfecção/métodos , Ondas Ultrassônicas , Animais , Barreira Hematoencefálica/efeitos da radiação , Imageamento por Ressonância Magnética/métodos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microbolhas , Transcriptoma
7.
J Neurooncol ; 156(1): 109-122, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34734364

RESUMO

PURPOSE: Glioblastoma (GB) poses formidable challenges to systemic immunotherapy approaches owing to the paucity of immune infiltration and presence of the blood brain/tumor barriers (BBB/BTB). We hypothesize that BBB/BTB disruption (BBB/BTB-D) with focused ultrasound (FUS) and microbubbles (MB) increases immune infiltration in GB. As a prelude to rational combination of FUS with ITx, we herein investigate the impact of localized BBB/BTB-D on innate and adaptive immune responses in an orthotopic murine GB model. METHODS: Mice with GL261 gliomas received i.v. MB and underwent FUS BBB/BTB-D (1.1 MHz, 0.5 Hz pulse repetition frequency, 10 ms bursts, 0.4-0.6 MPa). Brains, meninges, and peripheral lymphoid organs were excised and examined by flow cytometry 1-2 weeks following FUS. RESULTS: The number of dendritic cells (DC) was significantly elevated in GL261 tumors and draining cervical LN in response to sonication. CD86 + DC frequency was also upregulated with 0.6 MPa FUS, suggesting increased maturity. While FUS did not significantly alter CD8 + T cell frequency across evaluated organs, these cells upregulated checkpoint molecules at 1 week post-FUS, suggesting increased activation. By 2 weeks post-FUS, we noted emergence of adaptive resistance mechanisms, including upregulation of TIGIT on CD4 + T cells and CD155 on non-immune tumor and stromal cells. CONCLUSIONS: FUS BBB/BTB-D exerts mild, transient inflammatory effects in gliomas-suggesting that its combination with adjunct therapeutic strategies targeting adaptive resistance may improve outcomes. The potential for FUS-mediated BBB/BTB-D to modify immunological signatures is a timely and important consideration for ongoing clinical trials investigating this regimen in GB.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Terapia por Ultrassom , Animais , Barreira Hematoencefálica/patologia , Neoplasias Encefálicas/imunologia , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/terapia , Glioblastoma/imunologia , Glioblastoma/patologia , Glioblastoma/terapia , Imageamento por Ressonância Magnética/métodos , Camundongos
8.
Nature ; 537(7622): 652-5, 2016 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-27680938

RESUMO

Magnetic resonance imaging (MRI) provides fine spatial resolution, spectral sensitivity and a rich variety of contrast mechanisms for diagnostic medical applications. Nuclear imaging using γ-ray cameras offers the benefits of using small quantities of radioactive tracers that seek specific targets of interest within the body. Here we describe an imaging and spectroscopic modality that combines favourable aspects of both approaches. Spatial information is encoded into the spin orientations of tiny amounts of a polarized radioactive tracer using pulses of both radio-frequency electromagnetic radiation and magnetic-field gradients, as in MRI. However, rather than detecting weak radio-frequency signals, imaging information is obtained through the detection of γ-rays. A single γ-ray detector can be used to acquire an image; no γ-ray camera is needed. We demonstrate the feasibility of our technique by producing images and spectra from a glass cell containing only about 4 × 10(13) atoms (about 1 millicurie) of the metastable isomer (131m)Xe that were polarized using the laser technique of spin-exchange optical pumping. If the cell had instead been filled with water and imaged using conventional MRI, then it would have contained more than 10(24) water molecules. The high sensitivity of our modality expands the breadth of applications of magnetic resonance, and could lead to a new class of radioactive tracers.


Assuntos
Raios gama , Imageamento por Ressonância Magnética , Imagem Molecular/métodos , Análise Espectral/métodos , Traçadores Radioativos , Isótopos de Xenônio
9.
Clin Radiol ; 77(4): 291-298, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35177228

RESUMO

AIM: To prospectively analyse patients undergoing magnetic seed (Magseed) localisation (MSL) to evaluate the outcome, and to retrospectively compare re-excision rates for MSL with previous wire-guided localisation (WGL) to assess the hypothesis that the introduction of MSL may lead to a lower re-excision rate. MATERIALS AND METHODS: MSL commenced at University Hospital Crosshouse in December 2017. No other changes were made to radiological or surgical practice during this time. Data were collected prospectively on all patients undergoing MSL between December 2017 and December 2019, in a single breast unit. Data were gathered retrospectively on patients who had undergone localised breast procedures between January 2016 and December 2019 for comparison of re-excision rates. RESULTS: Two hundred and fifty-five patients underwent MSL surgery between December 2017 and December 2019. Of those, 98% (n=250) patients underwent successful MSL at the first attempt. The Magseed was identified intraoperatively in 100% patients and surgical excision was performed. The re-excision rate reduced from 18.9% in 2016/2017, to 11.6% in 2018/2019 (p=0.098). CONCLUSION: In conclusion, Magseed localisation has proved to be a safe and effective way of localising breast lesions, with the advantage of high accuracy. The reduction in re-excision rates at University Hospital Crosshouse with the introduction of Magseed® localisation is a potential benefit, which requires further study.


Assuntos
Procedimentos de Cirurgia Plástica , Radiologia , Hospitais Universitários , Humanos , Estudos Retrospectivos
10.
Magn Reson Med ; 86(5): 2822-2836, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34227163

RESUMO

PURPOSE: To characterize the differences between histogram-based and image-based algorithms for segmentation of hyperpolarized gas lung images. METHODS: Four previously published histogram-based segmentation algorithms (ie, linear binning, hierarchical k-means, fuzzy spatial c-means, and a Gaussian mixture model with a Markov random field prior) and an image-based convolutional neural network were used to segment 2 simulated data sets derived from a public (n = 29 subjects) and a retrospective collection (n = 51 subjects) of hyperpolarized 129Xe gas lung images transformed by common MRI artifacts (noise and nonlinear intensity distortion). The resulting ventilation-based segmentations were used to assess algorithmic performance and characterize optimization domain differences in terms of measurement bias and precision. RESULTS: Although facilitating computational processing and providing discriminating clinically relevant measures of interest, histogram-based segmentation methods discard important contextual spatial information and are consequently less robust in terms of measurement precision in the presence of common MRI artifacts relative to the image-based convolutional neural network. CONCLUSIONS: Direct optimization within the image domain using convolutional neural networks leverages spatial information, which mitigates problematic issues associated with histogram-based approaches and suggests a preferred future research direction. Further, the entire processing and evaluation framework, including the newly reported deep learning functionality, is available as open source through the well-known Advanced Normalization Tools ecosystem.


Assuntos
Semântica , Isótopos de Xenônio , Algoritmos , Ecossistema , Humanos , Processamento de Imagem Assistida por Computador , Pulmão/diagnóstico por imagem , Imageamento por Ressonância Magnética , Estudos Retrospectivos
11.
Magn Reson Med ; 86(6): 2966-2986, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34478584

RESUMO

Hyperpolarized (HP) 129 Xe MRI uniquely images pulmonary ventilation, gas exchange, and terminal airway morphology rapidly and safely, providing novel information not possible using conventional imaging modalities or pulmonary function tests. As such, there is mounting interest in expanding the use of biomarkers derived from HP 129 Xe MRI as outcome measures in multi-site clinical trials across a range of pulmonary disorders. Until recently, HP 129 Xe MRI techniques have been developed largely independently at a limited number of academic centers, without harmonizing acquisition strategies. To promote uniformity and adoption of HP 129 Xe MRI more widely in translational research, multi-site trials, and ultimately clinical practice, this position paper from the 129 Xe MRI Clinical Trials Consortium (https://cpir.cchmc.org/XeMRICTC) recommends standard protocols to harmonize methods for image acquisition in HP 129 Xe MRI. Recommendations are described for the most common HP gas MRI techniques-calibration, ventilation, alveolar-airspace size, and gas exchange-across MRI scanner manufacturers most used for this application. Moreover, recommendations are described for 129 Xe dose volumes and breath-hold standardization to further foster consistency of imaging studies. The intention is that sites with HP 129 Xe MRI capabilities can readily implement these methods to obtain consistent high-quality images that provide regional insight into lung structure and function. While this document represents consensus at a snapshot in time, a roadmap for technical developments is provided that will further increase image quality and efficiency. These standardized dosing and imaging protocols will facilitate the wider adoption of HP 129 Xe MRI for multi-site pulmonary research.


Assuntos
Pulmão , Isótopos de Xenônio , Pulmão/diagnóstico por imagem , Imageamento por Ressonância Magnética , Estudos Multicêntricos como Assunto , Ventilação Pulmonar , Respiração
12.
J Dairy Sci ; 104(11): 12009-12018, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34454762

RESUMO

Bovine respiratory disease (BRD) represents one of the major disease challenges affecting preweaning dairy-bred calves. Previous studies have shown that differences in feeding and activity behaviors exist between healthy and diseased calves affected by BRD. The aim of this study was to develop and assess the accuracy of models designed to predict BRD from feeding and activity behaviors. Feeding and activity behaviors were recorded for 100 male preweaning calves between ~8 to 42 d of age. Calves were group housed with ad libitum access to milk via automatic milk feeders, water, starter diet, and straw. Activity was monitored via a leg-mounted accelerometer. Health status of individual calves was monitored daily using an adapted version of the Wisconsin Scoring System to identify BRD. Three models were created to predict disease: (1) deviation from normal lying time based on moving averages (MA); (2) random forest (RF), a machine learning technique based on feeding and activity variables; and (3) a combination of RF and MA output. For the MA model, lying time was predicted based on behavior over previous days (3- and 7-d MA) and the expected value for the current day (based on calf age; measured using accelerometers). Data were not split into training and test data sets. Occasions when the actual lying time increased >9% of predicted lying time were classified as a deviation from normal and a disease alert was provided. Both feeding and activity behaviors were included within the RF model. Data were split into training (70%) and test (30%) data sets based on disease events. Events were classified as 2 d before, the day(s) of the disease event, and 2 d after the event. Accuracy of models was assessed using sensitivity, specificity, balanced accuracy, and Matthews correlation coefficient (MCC). If a positive disease prediction agreed with an actual disease event within a 3-d rolling window, it was classified as a true positive. Stand-alone models (RF; MA) showed high specificity (0.95; 0.97), moderate sensitivity (0.35; 0.43), balanced accuracy (0.65; 0.64), and MCC (0.25; 0.29). Combining outputs increased accuracy (specificity = 0.95, sensitivity = 0.54, balanced accuracy = 0.75, MCC = 0.36). The work presented is the first to demonstrate the use of modeling data derived from precision livestock farming techniques that monitor feeding and activity behaviors for early detection of BRD in preweaning calves, offering a significant advance in health management of youngstock.


Assuntos
Doenças dos Bovinos , Leite , Ração Animal/análise , Animais , Bovinos , Dieta , Comportamento Alimentar , Masculino , Desmame
13.
J Therm Biol ; 99: 102919, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34420654

RESUMO

This study aimed to investigate the correlation between strength and skin temperature (Tsk) asymmetries in the lower limbs of elite soccer players before and after a competitive season. The sample (n = 20) was composed of elite male soccer players. Strength asymmetry and Tsk asymmetry was measured through the countermovement jump (CMJ) test and infrared thermography, respectively. Asymmetries were quantified using the symmetry angle (SA) equation. A strong correlation was found between the SA of rate of force development (RFD) and the SA of Tsk before (baseline) (r = 0.7; r2 = 0.43; p = 0.03) and after (r = 0.6; r2 = 0.42; p = 0.04) the competitive season. Moreover, after the competitive season there were significant decreases in Peak force (p < 0.018), Impulse (p < 0.04), RFD (p = 0.0001) and CMJ height (p = 0.05), and significant increases in Tsk (p < 0.03), C-reactive protein (p = 0.03), Creatine kinase (p = 0.0001) and Cortisol (p = 0.04), even after a 3-day rest interval (no training). These results suggest that the CMJ test can be combined with infrared thermography for monitoring strength asymmetry and contribute to the prevention of muscle injuries.


Assuntos
Extremidade Inferior/fisiologia , Força Muscular , Temperatura Cutânea , Futebol/fisiologia , Adulto , Atletas , Humanos , Masculino , Termografia , Adulto Jovem
14.
Radiology ; 297(1): 201-210, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32779976

RESUMO

Background Apparent diffusion coefficient (ADC) maps of inhaled hyperpolarized gases have shown promise in the characterization of emphysema in patients with chronic obstructive pulmonary disease (COPD), yet an easily interpreted quantitative metric beyond mean and standard deviation has not been established. Purpose To introduce a quantitative framework with which to characterize emphysema burden based on hyperpolarized helium 3 (3He) and xenon 129 (129Xe) ADC maps and compare its diagnostic performance with CT-based emphysema metrics and pulmonary function tests (PFTs). Materials and Methods Twenty-seven patients with mild, moderate, or severe COPD and 13 age-matched healthy control subjects participated in this retrospective study. Participants underwent CT and multiple b value diffusion-weighted 3He and 129Xe MRI examinations and standard PFTs between August 2014 and November 2017. ADC-based emphysema index was computed separately for each gas and b value as the fraction of lung voxels with ADC values greater than in the healthy group 99th percentile. The resulting values were compared with quantitative CT results (relative lung area <-950 HU) as the reference standard. Diagnostic performance metrics included area under the receiver operating characteristic curve (AUC). Spearman rank correlations and Wilcoxon rank sum tests were performed between ADC-, CT-, and PFT-based metrics, and intraclass correlation was performed between repeated measurements. Results Thirty-six participants were evaluated (mean age, 60 years ± 6 [standard deviation]; 20 women). ADC-based emphysema index was highly repeatable (intraclass correlation coefficient > 0.99) and strongly correlated with quantitative CT (r = 0.86, P < .001 for 3He; r = 0.85, P < .001 for 129Xe) with high AUC (≥0.93; 95% confidence interval [CI]: 0.85, 1.00). ADC emphysema indices were also correlated with percentage of predicted diffusing capacity of lung for carbon monoxide (r = -0.81, P < .001 for 3He; r = -0.80, P < .001 for 129Xe) and percentage of predicted residual lung volume divided by total lung capacity (r = 0.65, P < .001 for 3He; r = 0.61, P < .001 for 129Xe). Conclusion Emphysema index based on hyperpolarized helium 3 or xenon 129 diffusion MRI provides a repeatable measure of emphysema burden, independent of gas or b value, with similar diagnostic performance as quantitative CT or pulmonary function metrics. © RSNA, 2020 Online supplemental material is available for this article. See also the editorial by Schiebler and Fain in this issue.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Enfisema Pulmonar/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Estudos de Casos e Controles , Feminino , Hélio , Humanos , Masculino , Pessoa de Meia-Idade , Testes de Função Respiratória , Isótopos de Xenônio
15.
Osteoarthritis Cartilage ; 28(4): 410-417, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32014493

RESUMO

OBJECTIVE: Weight loss has beneficial effects on clinical outcomes in knee osteoarthritis (OA), but the mechanism is still unclear. Since meniscus extrusion is associated with knee pain, this study assessed whether weight loss by diet and/or exercise is associated with less progression in meniscus extrusion measures over time. DESIGN: The Intensive Diet and Exercise for Arthritis trial (IDEA) was a prospective, single-blind, randomized-controlled trial including overweight and obese older adults with knee pain and radiographic OA. Participants were randomized to 18-month interventions: exercise only, diet only or diet + exercise. In a random subsample of 105 participants, MRIs were obtained at baseline and follow-up. The medial and lateral menisci were segmented and quantitative position and size measures were obtained, along with semiquantitative extrusion measures. Linear and log-binomial regression were used to examine the association between change in weight and change in meniscus measures. Between-group differences were analyzed using an analysis of covariance. RESULTS: Weight loss was associated with less progression over time of medial meniscus extrusion as measured by the maximum (ß: -24.59 µm, 95%CI: -41.86, -7.33) and mean (ß: -19.08 µm, 95%CI: -36.47, -1.70) extrusion distances. No relationships with weight loss were observed for lateral meniscus position, medial or lateral meniscus size or semiquantitative measures. Change in meniscus position and size did not differ significantly between groups. CONCLUSIONS: Weight loss was associated with beneficial modifications of medial meniscus extrusion over 18 months. This may be one of the mechanisms by which weight loss translates into a clinical benefit. CLINICAL TRIAL REGISTRATION: NCT00381290.


Assuntos
Dieta Redutora , Exercício Físico , Meniscos Tibiais/diagnóstico por imagem , Obesidade/terapia , Osteoartrite do Joelho/diagnóstico por imagem , Programas de Redução de Peso , Idoso , Progressão da Doença , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Meniscos Tibiais/patologia , Pessoa de Meia-Idade , Obesidade/complicações , Tamanho do Órgão , Osteoartrite do Joelho/complicações , Osteoartrite do Joelho/fisiopatologia , Sobrepeso/complicações , Sobrepeso/terapia , Método Simples-Cego , Redução de Peso
16.
Small ; 15(49): e1903460, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31642183

RESUMO

Microbubble activation with focused ultrasound (FUS) facilitates the noninvasive and spatially-targeted delivery of systemically administered therapeutics across the blood-brain barrier (BBB). FUS also augments the penetration of nanoscale therapeutics through brain tissue; however, this secondary effect has not been leveraged. Here, 1 MHz FUS sequences that increase the volume of transfected brain tissue after convection-enhanced delivery of gene-vector "brain-penetrating" nanoparticles were first identified. Next, FUS preconditioning is applied prior to trans-BBB nanoparticle delivery, yielding up to a fivefold increase in subsequent transgene expression. Magnetic resonance imaging (MRI) analyses of tissue temperature and Ktrans confirm that augmented transfection occurs through modulation of parenchymal tissue with FUS. FUS preconditioning represents a simple and effective strategy for markedly improving the efficacy of gene vector nanoparticles in the central nervous system.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Nanopartículas/química , Ondas Ultrassônicas , Animais , Barreira Hematoencefálica/diagnóstico por imagem , Barreira Hematoencefálica/metabolismo , Sistema Nervoso Central/diagnóstico por imagem , Sistema Nervoso Central/metabolismo , Imageamento por Ressonância Magnética , Microbolhas , Temperatura
17.
Osteoarthritis Cartilage ; 27(8): 1118-1123, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31009749

RESUMO

OBJECTIVE: Diet restriction and exercise form key treatments for osteoarthritis (OA) related symptoms in overweight and obese individuals. Although both interventions are known to influence systemic low-grade inflammation, which is related to pain levels and functional limitations, little is known about the potential changes in systemic inflammation as a working mechanism of diet restriction and exercise in knee OA. DESIGN: Data from the Arthritis, Diet, and Activity Promotion Trial (ADAPT) were used. Through causal mediation analyses, the proportion of the effect of a 18 months diet and exercise intervention explained by the 18 months change in interleukin (IL)-6, TNF-α, soluble IL-6 receptor, soluble IL-1 receptor, CRP, and BMI were assessed, using self-reported pain and function as outcomes. RESULTS: The change in inflammatory factors accounted for 15% of the total effect on pain and was totally independent of the change in BMI. The change in inflammatory factors accounted for 29% of the effect on function, with the change in BMI adding only 4% to the total mediated effect. CONCLUSIONS: The change in inflammatory factors after the diet and exercise intervention was a 'medium' size mediator of the effect on pain and a 'strong' mediator for the effect on function in overweight and obese individuals with knee OA. The change in BMI added minimally to the mediated effect on function. These results highlight the relevance of changes in systemic inflammation as drivers for clinically relevant effects after diet and exercise in overweight and obese individuals with knee OA.


Assuntos
Citocinas/sangue , Dieta Redutora , Exercício Físico , Osteoartrite do Joelho/terapia , Idoso , Índice de Massa Corporal , Proteína C-Reativa/análise , Feminino , Humanos , Masculino , Sobrepeso/terapia , Medição da Dor , Avaliação de Resultados da Assistência ao Paciente
18.
Mol Psychiatry ; 23(8): 1711-1716, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29112197

RESUMO

Despite ethnic differences in allele frequencies of variants in dopaminergic genes associated with dopamine D2/D3 receptor availability (D2R), no study to date has investigated the relationship between genetic ancestry and striatal D2R. Here, we show that ancestry-informative markers significantly predict dorsal striatal D2R in 117 healthy ethnically diverse residents of the New York metropolitan area using Positron Emission Tomography (PET) with [11C]raclopride (P<0.0001), while correcting for age, sex, BMI, education, smoking status, and estimated socioeconomic status (ZIP codes). Effects of ethnicity on D2R were not driven by variation in dopaminergic candidate genes. Instead, candidate gene associations with striatal D2R were diminished when correcting for ancestry. These findings imply that future studies investigating D2 receptor genes should covary for genetic ancestry or study homogeneous populations. Moreover, ancestry studies on human neurobiology should control for socioeconomic differences between ethnic groups.


Assuntos
Corpo Estriado/metabolismo , Grupos Raciais/genética , Receptores de Dopamina D2/metabolismo , Receptores de Dopamina D3/metabolismo , Adolescente , Adulto , Fatores Etários , Mapeamento Encefálico , Estudos de Coortes , Corpo Estriado/diagnóstico por imagem , Feminino , Frequência do Gene , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético , Tomografia por Emissão de Pósitrons , Racloprida , Compostos Radiofarmacêuticos , Receptores de Dopamina D2/genética , Receptores de Dopamina D3/genética , Fatores Socioeconômicos , Adulto Jovem
19.
Arthroscopy ; 35(10): 2845-2846, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31604502

RESUMO

Hip arthroscopy for femoroacetabular impingement has generally been considered to enjoy a high rate of success. These patients tend to be young and active. One measure of "success" has been return to sport. However, much of the literature has used subjective return criteria and reported on diverse groups in terms of skill levels, sports, and sexes, as well as small numbers, thus limiting specific recommendations.


Assuntos
Basquetebol , Impacto Femoroacetabular , Artroscopia , Seguimentos , Articulação do Quadril , Humanos , Volta ao Esporte
20.
Int J Obes (Lond) ; 42(4): 634-640, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-28984843

RESUMO

BACKGROUND/OBJECTIVE: Family relationships have been linked to obesity and related disorders in youth, but few studies have provided causal evidence of this association. This study tested the impact of a family psychosocial intervention on components of metabolic syndrome-a condition driven largely by abdominal obesity-in African American youth. In particular, the study tested whether effects were strongest among those who started at highest risk, that is, with high levels of unsupportive parenting at baseline. SUBJECTS/METHODS: Randomized clinical trial of a community sample of 391 African American youth (mean age=11.2 years) conducted in 2001-2002, with follow-up metabolic syndrome assessment in 2014-2015. Participants were assigned either to receive a weekly family intervention or to a control group. The primary study outcome was the number of components of metabolic syndrome that were clinically elevated at age 25, including central adiposity, blood pressure, triglycerides, glucose and low high-density lipoproteins. Unsupportive parenting was measured by questionnaires at baseline. RESULTS: Significant interaction effects were found between group assignment and baseline unsupportive parenting on counts of metabolic syndrome components in youth (beta=-0.17, P=0.03). Among those who started with higher levels of unsupportive parenting at age 11, participation in the family intervention reduced the number of clinically elevated components of the metabolic syndrome at age 25 relative to the control group. No such effect was seen among those who started with good parenting. Mediation analyses suggested that changes in the psychosocial targets of the parenting intervention partially accounted for the effects amongst those high in unsupportive parenting at baseline (effect size=-0.350, s.e.=0.178). CONCLUSIONS: These findings suggest that efforts to improve family relationships may be able to ameliorate the detrimental effects that harsh and unsupportive parenting have on obesity-related outcomes such as metabolic syndrome in youth.


Assuntos
Negro ou Afro-Americano , Terapia Familiar , Síndrome Metabólica/epidemiologia , Poder Familiar/psicologia , Negro ou Afro-Americano/psicologia , Negro ou Afro-Americano/estatística & dados numéricos , Criança , Seguimentos , Humanos , Apoio Social , Inquéritos e Questionários
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