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81.
Shile Qi Rogers F. Silva Daoqiang Zhang Sergey M. Plis Robyn Miller Victor M. Vergara Rongtao Jiang Dongmei Zhi Jing Sui Vince D. Calhoun 《Human brain mapping》2022,43(4):1280
Advances in imaging acquisition techniques allow multiple imaging modalities to be collected from the same subject. Each individual modality offers limited yet unique views of the functional, structural, or dynamic temporal features of the brain. Multimodal fusion provides effective ways to leverage these complementary perspectives from multiple modalities. However, the majority of current multimodal fusion approaches involving functional magnetic resonance imaging (fMRI) are limited to 3D feature summaries that do not incorporate its rich temporal information. Thus, we propose a novel three‐way parallel group independent component analysis (pGICA) fusion method that incorporates the first‐level 4D fMRI data (temporal information included) by parallelizing group ICA into parallel ICA via a unified optimization framework. A new variability matrix was defined to capture subject‐wise functional variability and then link it to the mixing matrices of the other two modalities. Simulation results show that the three‐way pGICA provides highly accurate cross‐modality linkage estimation under both weakly and strongly correlated conditions, as well as comparable source estimation under different noise levels. Results using real brain imaging data identified one linked functional–structural–diffusion component associated to differences between schizophrenia and controls. This was replicated in an independent cohort, and the identified components were also correlated with major cognitive domains. Functional network connectivity revealed visual–subcortical and default mode‐cerebellum pairs that discriminate between schizophrenia and controls. Overall, both simulation and real data results support the use of three‐way pGICA to identify multimodal spatiotemporal links and to pursue the study of brain disorders under a single unifying multimodal framework. 相似文献
82.
Amy S. Badura-Brack Mackenzie S. Mills Christine M. Embury Maya M. Khanna Alicia Klanecky Earl Julia M. Stephen Yu-Ping Wang Vince D. Calhoun Tony W. Wilson 《Journal of psychiatry & neuroscience : JPN》2020,45(4):288
BackgroundChildhood trauma is reliably associated with smaller hippocampal volume in adults; however, this finding has not been shown in children, and even less is known about how sex and trauma interact to affect limbic structural development in children.MethodsTypically developing children aged 9 to 15 years who completed a trauma history questionnaire and structural T1-weighted MRI were included in this study (n = 172; 85 female, 87 male). All children who reported 4 or more traumas (n = 36) composed the high trauma group, and all children who reported 3 or fewer traumas (n = 136) composed the low trauma group. Using multivariate analysis of covariance, we compared FreeSurfer-derived structural MRI volumes (normalized by total intracranial volume) of the amygdalar, hippocampal and parahippocampal regions by sex and trauma level, controlling for age and study site.ResultsWe found a significant sex × trauma interaction, such that girls with high trauma had greater volumes than boys with high trauma. Follow-up analyses indicated significantly increased volumes for girls and generally decreased volumes for boys, specifically in the hippocampal and parahippocampal regions for the high trauma group; we observed no sex differences in the low trauma group. We noted no interaction effect for the amygdalae.LimitationsWe assessed a community sample and did not include a clinical sample. We did not collect data about the ages at which children experienced trauma.ConclusionResults revealed that psychological trauma affects brain development differently in girls and boys. These findings need to be followed longitudinally to elucidate how structural differences progress and contribute to well-known sex disparities in psychopathology. 相似文献
83.
Preventing Episodic Migraine With Caloric Vestibular Stimulation: A Randomized Controlled Trial 下载免费PDF全文
David Wilkinson PhD Kristen K. Ade PhD Lesco L. Rogers MD Deborah K. Attix PhD Maragatha Kuchibhatla PhD Martin D. Slade MPH Lanty L. Smith LLB Kathryn P. Poynter RN Daniel T. Laskowitz MD Marshall C. Freeman MD Michael E. Hoffer MD Joel R. Saper MD Dianne L. Scott MD Mohamed Sakel MD Anne H. Calhoun MD Robert D. Black PhD 《Headache》2017,57(7):1065-1087
84.
Shile Qi Jing Sui Jiayu Chen Jingyu Liu Rongtao Jiang Rogers Silva Armin Iraji Eswar Damaraju Mustafa Salman Dongdong Lin Zening Fu Dongmei Zhi Jessica A. Turner Juan Bustillo Judith M. Ford Daniel H. Mathalon James Voyvodic Sarah McEwen Adrian Preda Aysenil Belger Steven G. Potkin Bryon A. Mueller Tulay Adali Vince D. Calhoun 《Human brain mapping》2019,40(13):3795-3809
There is growing evidence that rather than using a single brain imaging modality to study its association with physiological or symptomatic features, the field is paying more attention to fusion of multimodal information. However, most current multimodal fusion approaches that incorporate functional magnetic resonance imaging (fMRI) are restricted to second‐level 3D features, rather than the original 4D fMRI data. This trade‐off is that the valuable temporal information is not utilized during the fusion step. Here we are motivated to propose a novel approach called “parallel group ICA+ICA” that incorporates temporal fMRI information from group independent component analysis (GICA) into a parallel independent component analysis (ICA) framework, aiming to enable direct fusion of first‐level fMRI features with other modalities (e.g., structural MRI), which thus can detect linked functional network variability and structural covariations. Simulation results show that the proposed method yields accurate intermodality linkage detection regardless of whether it is strong or weak. When applied to real data, we identified one pair of significantly associated fMRI‐sMRI components that show group difference between schizophrenia and controls in both modalities, and this linkage can be replicated in an independent cohort. Finally, multiple cognitive domain scores can be predicted by the features identified in the linked component pair by our proposed method. We also show these multimodal brain features can predict multiple cognitive scores in an independent cohort. Overall, results demonstrate the ability of parallel GICA+ICA to estimate joint information from 4D and 3D data without discarding much of the available information up front, and the potential for using this approach to identify imaging biomarkers to study brain disorders. 相似文献
85.
Coexistence of gallbladder disease and morbid obesity 总被引:5,自引:0,他引:5
To further investigate the relationship between gallbladder disease and morbid obesity, 92 morbidly obese patients underwent routine cholecystectomy at the time of their bariatric procedures. The preoperative ultrasonographic findings were positive in only 20 patients. Of the 92 patients who underwent cholecystectomy, 87 (95 percent) had pathologic evidence of gallbladder disease. This included cholecystitis, cholesterolosis, cholelithiasis, or some combination of the three. The incidence of postoperative cholecystitis, the technical difficulty of reoperation, the unnecessary expense and exposure to a second hospitalization and a second operation are all completely eliminated when routine cholecystectomy is performed in concert with elective bariatric procedures. 相似文献
86.
87.
Raitt MH Connor WE Morris C Kron J Halperin B Chugh SS McClelland J Cook J MacMurdy K Swenson R Connor SL Gerhard G Kraemer DF Oseran D Marchant C Calhoun D Shnider R McAnulty J 《JAMA》2005,293(23):2884-2891
Context Clinical studies of omega-3 polyunsaturated fatty acids (PUFAs) have shown a reduction in sudden cardiac death, suggesting that omega-3 PUFAs may have antiarrhythmic effects. Objective To determine whether omega-3 PUFAs have beneficial antiarrhythmic effects in patients with a history of sustained ventricular tachycardia (VT) or ventricular fibrillation (VF). Design and Setting Randomized, double-blind, placebo-controlled trial performed at 6 US medical centers with enrollment from February 1999 until January 2003. Patients Two hundred patients with an implantable cardioverter defibrillator (ICD) and a recent episode of sustained VT or VF. Intervention Patients were randomly assigned to receive fish oil, 1.8 g/d, 72% omega-3 PUFAs, or placebo and were followed up for a median of 718 days (range, 20-828 days). Main Outcome Measures Time to first episode of ICD treatment for VT/VF, changes in red blood cell concentrations of omega-3 PUFAs, frequency of recurrent VT/VF events, and predetermined subgroup analyses. Results Patients randomized to receive fish oil had an increase in the mean percentage of omega-3 PUFAs in red blood cell membranes from 4.7% to 8.3% (P<.001), with no change observed in patients receiving placebo. At 6, 12, and 24 months, 46% (SE, 5%), 51% (5%), and 65% (5%) of patients randomized to receive fish oil had ICD therapy for VT/VF compared with 36% (5%), 41% (5%), and 59% (5%) for patients randomized to receive placebo (P = .19). In the subset of 133 patients whose qualifying arrhythmia was VT, 61% (SE, 6%), 66% (6%), and 79% (6%) of patients in the fish oil group had VT/VF at 6, 12, and 24 months compared with 37% (6%), 43% (6%), and 65% (6%) of patients in the control group (P = .007). Recurrent VT/VF events were more common in patients randomized to receive fish oil (P<.001). Conclusion Among patients with a recent episode of sustained ventricular arrhythmia and an ICD, fish oil supplementation does not reduce the risk of VT/VF and may be proarrhythmic in some patients. 相似文献
88.
BACKGROUND: Controversy exists regarding axillary dissection (ALND) for sentinel node (SLN) metastases detected as isolated tumor cells (ITC). We hypothesized that the number of positive non-SLNs is low and ALND is unnecessary for most patients with ITC. METHODS: From 1995 to 1999, 634 breast cancer patients underwent SLND. SLNs were examined using immunohistochemistry if hematoxylin and eosin was negative. ALND was recommended for ITC-positive SLNs. RESULTS: Seventy-eight patients (12.3%) with ITC-positive SLNs were offered ALND. Sixty-one consented, whereas 17 refused. Fifty-eight (95.1%) had negative non-SLNs. Three (4.9%) had non-SLN metastases. One patient (1.6%) had macrometastatic disease, whereas 2 (3.3%) had micrometastases. No ITC-only-positive SLN patient experienced axillary recurrence. CONCLUSIONS: When ALND was performed for ITC, 1.6% of non-SLNs harbored macrometastases and 3.3% had micrometastases. When ALND was not performed, axillary recurrence was not seen. The low risk of non-SLN disease in this study fails to support the routine use of ALND for ITC-positive SLNs. 相似文献
89.
James W. Selby Lawrence G. Calhoun Richard E. Johnson 《Journal of community psychology》1977,5(3):290-294
This study explored the major categories of causal explanations used by naive observers to account for psychological problems. A pool of items describing potential causes psychological problems was generated using psychiatric and psychological theory and research and pilot work. Three hundred and ninety-four subjects rated each cause. The results were factor analyzed and five interpretable factors resulted: Factor I, Personal Characteristics: Factor II, Organic Causes; Factor III, Natural Disasters; Factor IV, Marital Crises; and Factor V, Childhood Family Conditions. It was suggested that these five dimensions can be useful in further study of the perceived causes of psychological disorders. 相似文献
90.
Armin Iraji Thomas P. Deramus Noah Lewis Maziar Yaesoubi Julia M. Stephen Erik Erhardt Aysneil Belger Judith M. Ford Sarah McEwen Daniel H. Mathalon Bryon A. Mueller Godfrey D. Pearlson Steven G. Potkin Adrian Preda Jessica A. Turner Jatin G. Vaidya Theo G. M. van Erp Vince D. Calhoun 《Human brain mapping》2019,40(10):3058-3077
The brain is highly dynamic, reorganizing its activity at different interacting spatial and temporal scales, including variation within and between brain networks. The chronnectome is a model of the brain in which nodal activity and connectivity patterns change in fundamental and recurring ways over time. Most literature assumes fixed spatial nodes/networks, ignoring the possibility that spatial nodes/networks may vary in time. Here, we introduce an approach to calculate a spatially fluid chronnectome (called the spatial chronnectome for clarity), which focuses on the variations of networks coupling at the voxel level, and identify a novel set of spatially dynamic features. Results reveal transient spatially fluid interactions between intra‐ and internetwork relationships in which brain networks transiently merge and separate, emphasizing dynamic segregation and integration. Brain networks also exhibit distinct spatial patterns with unique temporal characteristics, potentially explaining a broad spectrum of inconsistencies in previous studies that assumed static networks. Moreover, we show anticorrelative connections to brain networks are transient as opposed to constant across the entire scan. Preliminary assessments using a multi‐site dataset reveal the ability of the approach to obtain new information and nuanced alterations that remain undetected during static analysis. Patients with schizophrenia (SZ) display transient decreases in voxel‐wise network coupling within visual and auditory networks, and higher intradomain coupling variability. In summary, the spatial chronnectome represents a new direction of research enabling the study of functional networks which are transient at the voxel level, and the identification of mechanisms for within‐ and between‐subject spatial variability. 相似文献