Journal articles on the topic 'Tensor methods, Factor analysis, Multilinear regression'
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Bui, Moayedi, Gör, Jaafari, and Foong. "Predicting Slope Stability Failure through Machine Learning Paradigms." ISPRS International Journal of Geo-Information 8, no. 9 (September 4, 2019): 395. http://dx.doi.org/10.3390/ijgi8090395.
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In this study, we employed various machine learning-based techniques in predicting factor of safety against slope failures. Different regression methods namely, multi-layer perceptron (MLP), Gaussian process regression (GPR), multiple linear regression (MLR), simple linear regression (SLR), support vector regression (SVR) were used. Traditional methods of slope analysis (e.g., first established in the first half of the twentieth century) used widely as engineering design tools. Offering more progressive design tools, such as machine learning-based predictive algorithms, they draw the attention of many researchers. The main objective of the current study is to evaluate and optimize various machine learning-based and multilinear regression models predicting the safety factor. To prepare training and testing datasets for the predictive models, 630 finite limit equilibrium analysis modelling (i.e., a database including 504 training datasets and 126 testing datasets) were employed on a single-layered cohesive soil layer. The estimated results for the presented database from GPR, MLR, MLP, SLR, and SVR were assessed by various methods. Firstly, the efficiency of applied models was calculated employing various statistical indices. As a result, obtained total scores 20, 35, 50, 10, and 35, respectively for GPR, MLR, MLP, SLR, and SVR, revealed that the MLP outperformed other machine learning-based models. In addition, SVR and MLR presented an almost equal accuracy in estimation, for both training and testing phases. Note that, an acceptable degree of efficiency was obtained for GPR and SLR models. However, GPR showed more precision. Following this, the equation of applied MLP and MLR models (i.e., in their optimal condition) was derived, due to the reliability of their results, to be used in similar slope stability problems.
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Onyeonoro, Ugochukwu U., Joseph N. Chukwu, Charles C. Nwafor, Anthony O. Meka, Babatunde I. Omotowo, Nelson O. Madichie, Chidubem Ogbudebe, et al. "Evaluation of Patient Satisfaction with Tuberculosis Services in Southern Nigeria." Health Services Insights 8 (January 2015): HSI.S27177. http://dx.doi.org/10.4137/hsi.s27177.
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Objective Knowing tuberculosis (TB) patients’ satisfaction enables TB program managers to identify gaps in service delivery and institute measures to address them. This study is aimed at evaluating patients’ satisfaction with TB services in southern Nigeria. Materials and Methods A total of 378 patients accessing TB care were studied using a validated Patient Satisfaction (PS-38) questionnaire on various aspects of TB services. Factor analysis was used to identify eight factors related to TB patient satisfaction. Test of association was used to study the relation between patient satisfaction scores and patient and health facility characteristics, while multilinear regression analysis was used to identify predictors of patient satisfaction. Results Highest satisfaction was reported for adherence counseling and access to care. Patient characteristics were associated with overall satisfaction, registration, adherence counseling, access to care, amenities, and staff attitude, while health system factors were associated with staff attitude, amenities, and health education. Predictors of satisfaction with TB services included gender, educational status, if tested for HIV, distance, payment for TB services, and level and type of health-care facility. Conclusion Patient- and health system–related factors were found to influence patient satisfaction and, hence, should be taken into consideration in TB service programing.
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Pisl, V., J. Vevera, and J. Volavka. "Changes of ambulance departures to assaults during COVID-19 pandemic restrictions." European Psychiatry 65, S1 (June 2022): S519. http://dx.doi.org/10.1192/j.eurpsy.2022.1324.
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Introduction Restrictions related to COVID-19 may affect aggressive behaviour. Increased incidence of gender-based, domestic, and intimate-partner violence was expected during the pandemic, however, retrospective analyses yielded contradicting results. Objectives Examine changes in frequency of assaults caused by pandemic restrictions, including separate analysis for male and female assault victims, for residential and non-residential location of assaults and for assaults related to domestic violence. Methods Weekly number of ambulance departures to injuries secondary to assaults in the Pilsen region, Czechia, during the COVID lockdown was compared to records from the three previous years using ANOVA and post hoc t-tests. Further, multilinear regression was used to model weekly number of ambulance departures between 1st January 2017 and 30th April 2021 based on presence of pandemic national emergency state, time, and seasonality. Results During pandemic lockdown, ambulance departures to assaults dropped by 43% compared to equivalent periods of the three previous years. The decrease was notable specifically among departures to male victims and to assaults in non-residential areas, with only small decrease observed for female victims and assaults related to domestic violence and no change found in frequency of assaults happening at home. Conclusions Lockdowns and restrictions of public life were associated with a decreased incidence of violent assaults. While the incidence decreased especially in males and in those assaulted outside of their homes, we found no support for an increase in domestic or gender related violence. Pandemic restrictions may serve as a protective rather than a risk factor for assaults. Disclosure No significant relationships.
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Kim, Hyangkyoung, Tae-Won Kwon, Eol Choi, Seonjeong Jeong, Hong-Kyu Kim, Youngjin Han, Yong-Pil Cho, Hyun-Ki Yoon, Jaewon Choe, and Won Hong Kim. "Aortoiliac diameter and length in a healthy cohort." PLOS ONE 17, no. 5 (May 5, 2022): e0268077. http://dx.doi.org/10.1371/journal.pone.0268077.
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Objective Diameter is currently the only screening and diagnostic criterion for asymptomatic aneurysms. Therefore, aortic and lower-extremity arterial diameter has diagnostic, therapeutic, and prognostic importance. We aimed to determine aortic and lower-extremity arterial reference diameters in a general population and compare them according to age, sex, and other characteristics. Methods We evaluated consecutive 3,692 patients who underwent computed tomography as part of a general health checkup from 2015–2019 in a single tertiary center. Aortic and lower-extremity arterial diameters and the most important factor related to arterial diameters were evaluated. Results The mean diameter of the abdominal aorta was 17.490 ± 2.110 mm, while that of the common iliac artery was 10.851 ± 1.689 mm. The mean diameter of the abdominal aorta was 18.377 ± 1.766 mm in men and 15.884 ± 1.694 mm in women. Significant intersex differences were observed for all mean diameters and lengths. Multilinear regression analysis showed that age, sex, and body surface area impacted mean diameters of all measured sites except aorta and common iliac artery length. Between male and female patients matched for body surface area, there were significant intersex differences for all measured sites, except for common iliac artery length. Conclusions The mean diameter of the abdominal aorta in this healthy cohort was 17.490 ± 2.110 mm overall, 18.377 ± 1.766 mm in men, and 15.884 ± 1.694 mm in women. Arterial diameter increased with male sex, older age, and increased body surface area, and aortic diameters were larger in men than in women with the same body surface area.
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Mauch, Jaclyn T., Irfan A. Rhemtulla, Evan B. Katzel, J. Andres Hernandez, Robyn B. Broach, and Joseph M. Serletti. "Does Size Matter: Evaluating the Difference between Right and Left Internal Mammary Veins in Free Flap Breast Reconstruction." Journal of Reconstructive Microsurgery 35, no. 09 (July 14, 2019): 677–81. http://dx.doi.org/10.1055/s-0039-1693157.
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Background Venous congestion in breast free flap reconstruction continues to be a major reason for flap compromise requiring reoperative exploration and possible flap failure. We aim to investigate whether size of the internal mammary vein (IMV) (1) varies between the left and right sides, (2) changes with certain patient demographics or preoperative factors, and (3) correlates with postoperative complications. Methods We performed a retrospective cohort study examining all patients undergoing free flap breast reconstruction from September 2005 to March 2016 using internal mammary recipient veins. Venous coupler size was used as a surrogate measure of IMV diameter. Preoperative patient characteristics and factors were collected. Postoperative outcomes assessed included thrombosis, flap loss, fat necrosis, and mastectomy flap necrosis. Multivariate analyses were performed to evaluate if preoperative factors affected IMV diameter and to determine if coupler size and flap side were independent risk factors for postoperative complications. Results We examined 372 patients with a total of 561 flaps. One hundred eighty-nine patients received bilateral flaps with the IMV as a recipient. The right IMV (n = 286, average = 2.97 mm, standard deviation [SD] = 0.41) was significantly larger than the left (n = 275, average = 2.89, SD = 0.35, p = 0.008). Preoperative factors and postoperative complications were not statistically different between the left and right cohorts. The multivariable linear regression model with coupler size as the dependent variable found older age trended toward a larger coupler size but this was not significant (p = 0.05). In multilinear regression analysis, the postoperative outcomes did not have significant covariates. Conclusion We found that IMV size significantly differs between the right and the left sides. However, incidence of postoperative complications was not significantly different between the left and right sides, and the multivariate analyses did not identify flap side as an independent risk factor for adverse outcomes. Prospective studies evaluating actual IMV diameter and associated complications may potentially elucidate clinical significance.
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Nakamura, Yuko, Shuntaro Ando, Syudo Yamasaki, Naohiro Okada, Atsushi Nishida, Kiyoto Kasai, Saori Tanaka, Hironori Nakatani, and Shinsuke Koike. "Dietary Restraint Related to Body Weight Maintenance and Neural Processing in Value-Coding Areas in Adolescents." Journal of Nutrition 151, no. 7 (April 13, 2021): 2059–67. http://dx.doi.org/10.1093/jn/nxab068.
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ABSTRACT Background There is an alarming increase in the obesity prevalence among children in an environment of increasing availability of preprocessed high-calorie foods. However, some people maintain a healthy weight even in such obesogenic environments. This difference in body weight management could be attributed to individual differences in dietary restraint; however, its underlying neurocognitive mechanisms in adolescents remain unclear. Objectives This study aimed to elucidate these neurocognitive mechanisms in adolescents by examining the relationships between dietary restraint and the food-related value-coding region located in the ventromedial prefrontal cortex (vmPFC). Methods The association between dietary restraint and BMI was tested using a multilinear regression analysis in a large early adolescent cohort (n = 2554; age, 12.2 ± 0.3 years; BMI, 17.9 ± 2.5 kg/m2; 1354 boys). Further, an fMRI experiment was designed to assess the association between the vmPFC response to food images and dietary restraint in 30 adolescents (age, 17.6 ± 1.9 years; BMI, 20.7 ± 2.2 kg/m2; 13 boys). Additionally, using 54 individuals from the cohort (age, 14.5 ± 0.6 years; BMI, 18.8 ± 2.6 kg/m2; 31 boys), we assessed the association between dietary restraint and intrinsic vmPFC-related functional connectivity. Results In the cohort, adolescents with increased dietary restraint showed a lower BMI (β = −0.38; P < 0.001; B = −0.06; SE = 0.003). The fMRI results showed a decreased vmPFC response to high-calorie food were correlated with greater dietary restraint. Moreover, there was an association of attenuated intrinsic vmPFC-related functional connectivity in the superior and middle frontal gyrus and the middle temporal gyrus with greater dietary restraint. Conclusions Our findings suggest that dietary restraint in adolescents could be a preventive factor for weight gain; its effect involves modulating the vmPFC, which is associated with food value coding.
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Sekula, Piotr, Zbigniew Ustrnul, Anita Bokwa, Bogdan Bochenek, and Miroslaw Zimnoch. "Random Forests Assessment of the Role of Atmospheric Circulation in PM10 in an Urban Area with Complex Topography." Sustainability 14, no. 6 (March 14, 2022): 3388. http://dx.doi.org/10.3390/su14063388.
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This study presents the assessment of the quantitative influence of atmospheric circulation on the pollutant concentration in the area of Kraków, Southern Poland, for the period 2000–2020. The research has been realized with the application of different statistical parameters, synoptic meteorology tools, the Random Forests machine learning method, and multilinear regression analyses. Another aim of the research was to evaluate the types of atmospheric circulation classification methods used in studies on air pollution dispersion and to assess the possibility of their application in air quality management, including short-term PM10 daily forecasts. During the period analyzed, a significant decreasing trend of pollutants’ concentrations and varying atmospheric circulation conditions was observed. To understand the relation between PM10 concentration and meteorological conditions and their significance, the Random Forests algorithm was applied. Observations from meteorological stations, air quality measurements and ERA-5 reanalysis were used. The meteorological database was used as an input to models that were trained to predict daily PM10 concentration and its day-to-day changes. This study made it possible to distinguish the dominant circulation types with the highest probability of occurrence of poor air quality or a significant improvement in air quality conditions. Apart from the parameters whose significant influence on air quality is well established (air temperature and wind speed at the ground and air temperature gradient), the key factor was also the gradient of relative air humidity and wind shear in the lowest troposphere. Partial dependence calculated with the use of the Random Forests model made it possible to better analyze the impact of individual meteorological parameters on the PM10 daily concentration. The analysis has shown that, for areas with a diversified topography, it is crucial to use the variability of the atmospheric circulation during the day to better forecast air quality.
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Biesbroek, J. Matthijs, Alexander Leemans, Hanna den Bakker, Marco Duering, Benno Gesierich, Huiberdina L. Koek, Esther van den Berg, Albert Postma, and Geert Jan Biessels. "Microstructure of Strategic White Matter Tracts and Cognition in Memory Clinic Patients with Vascular Brain Injury." Dementia and Geriatric Cognitive Disorders 44, no. 5-6 (2017): 268–82. http://dx.doi.org/10.1159/000485376.
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Background: White matter injury is an important factor for cognitive impairment in memory clinic patients. We determined the added value of diffusion tensor imaging (DTI) of strategic white matter tracts in explaining variance in cognition in memory clinic patients with vascular brain injury. Methods: We included 159 patients. Conventional MRI markers (white matter hyperintensity volume, lacunes, nonlacunar infarcts, brain atrophy, and microbleeds), and fractional anisotropy and mean diffusivity (MD) of the whole brain white matter and of 18 white matter tracts were related to cognition using linear regression and Bayesian network analysis. Results: On top of all conventional MRI markers combined, MD of the whole brain white matter explained an additional 3.4% (p = 0.014), 7.8% (p < 0.001), and 1.2% (p = 0.119) variance in executive functioning, speed, and memory, respectively. The Bayesian analyses of regional DTI measures identified strategic tracts for executive functioning (right superior longitudinal fasciculus), speed (left corticospinal tract), and memory (left uncinate fasciculus). MD within these tracts explained an additional 3.4% (p = 0.012), 3.8% (p = 0.007), and 2.1% (p = 0.041) variance in executive functioning, speed, and memory, respectively, on top of all conventional MRI and global DTI markers combined. Conclusion: In memory clinic patients with vascular brain injury, DTI of strategic white matter tracts has a significant added value in explaining variance in cognitive functioning.
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Blanc, Judite, Azizi Seixas, Sean Small, Clarence Locklear, Rodginie Dorcent, Evan Auguste, Daniel Buysse, and Girardin Jean-Louis. "0612 Does Coping Strategy Protect Sleep Quality During COVID-19? An Examination of Racial, Ethnic, Cultural Differences." Sleep 45, Supplement_1 (May 25, 2022): A268—A269. http://dx.doi.org/10.1093/sleep/zsac079.609.
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Abstract Introduction Little has been done to examine within/between group predictors and mediators of race/ethnic differences in sleep health outcomes, due to COVID-19 exposure. We evaluated the effect of COVID-19 exposure on sleep quality in a multiracial/ethnic sample of New York residents. Methods We conducted a cross-sectional study among adults exposed to COVID-19 across New York State from September to November of 2020. Comparisons of participant characteristics e.g., mean scores by race/ethnicity status were made using one-way ANOVA for continuous variables, and chi-square tests for categorical variables. Associations between social determinants of health (employment, location), Trauma Coping Self-Efficacy (CES-T), and sleep quality (Pittsburgh Sleep Quality Index-PSQI) were examined using multilinear regression analysis stratified by race/ethnicity. Results Of the 541 participants, 373 (68.9%) were female; mean age was 40.9 years (SD=15), 198 (36.6%) identified as Whites, 111 (20.5%) as Black, 97 (17.9%) as Hispanics, and 135(25%) identified as either Asians, Native-Americans, Pacific-Islanders. Sex was the strongest predictor [β = 1.335; p < .05] of sleep quality, but only among Whites. Trauma Coping Self-Efficacy was negatively associated with sleep quality among Asian, Native-American, or Pacific-Islander participants [β = -.114; p < .05 ]; Black [β = -.099; p < .05] and White participants [β = -0.79; p < .05] but not among Latinos/as [β = -.058; p = 0.71]. Conclusion Coping Self-Efficacy moderated the effect of COVID-19 on sleep quality among some, but not all, racial/ethnic groups. While CSE-T scores during the first wave of COVID-19 acted as a protective factor for sleep quality among Asians, Native-Americans, and Pacific-Islanders, White and Black participants, this was not the case for Latinos/as/Hispanics residing in New York. Clinical interventions that are tailored for racial/ethnic, community and cultural needs may help to mitigate sleep problems associated with COVID-19 exposure. Support (If Any) T32HL129953; 7R01HL142066-04; 1R01HL152453-01
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Sebaldt, R. J., D. O. Adams, and R. J. Uhing. "Quantification of contributions of phospholipid precursors to diradylglycerols in stimulated mononuclear phagocytes." Biochemical Journal 284, no. 2 (June 1, 1992): 367–75. http://dx.doi.org/10.1042/bj2840367.
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Phosphatidylcholine (PC) hydrolysis has been shown to occur in hormone-stimulated cells and represents a potential metabolic source, in addition to phosphoinositides, for the generation of diradylglycerols (DG). We performed studies in order to quantify the importance of this pathway in DG formation. We incubated murine peritoneal macrophages with platelet-activating factor (PAF), ionomycin, phorbol myristate acetate (PMA) or no stimulus in a series of timed incubations ranging from 15 s to 20 min. We quantified the profiles of the molecular species in the accumulated DG after extraction, specific radiolabelling to give [32P]phosphatidic acid by DG kinase, and conversion to the dimethyl derivative. We used two independent methods for molecular species analysis: (1) reversed-phase h.p.l.c. separation with in-line beta-radiation detection of peaks, and (2) an argentation-t.l.c. separation with scintillation counting of bands. Our results showed a clearly biphasic sequence in the composition of accumulated DG. The molecular species composition of early DG (up to 1 min stimulation time) was very similar to that of unstimulated DG, whereas the proportions of the species present in later DG were substantially altered. In the same experiments, we extracted native phospholipids from unstimulated macrophages, separated phosphatidylinositol (PI), PC, phosphatidylethanolamine (PE) and phosphatidylserine (PS), converted them to the corresponding DGs by using phospholipase C, and determined their molecular species compositions as above. In comparison with the diradyl compositions of stimulated DG, the diradyl composition of PI closely matched that of early DG, the differences between the PC and PI compositions matched the differences between early and late DG very closely, and the compositions of PE and PS were unique and unrelated. We quantified these relationships more precisely by multilinear regression analysis to calculate the theoretical best mix of five molecular species compositions (PI, PC, PE, PS and unstimulated DG) that would most closely replicate the early and late accumulated DG compositions. We found that by both h.p.l.c. and t.l.c. analyses, 15-30% (PAF) or 25-50% (ionomycin and PMA) of the later DG could be accounted for by PC hydrolysis. These results represent quantifications of phospholipid class contributions to stimulated DG formation, and demonstrate the potential importance of PC hydrolysis in phagocytic leucocytes.
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Lee, Chih-Ying, Hsiu-Ling Chen, Pei-Chin Chen, Yueh-Sheng Chen, Pi-Ling Chiang, Cheng-Kang Wang, Cheng-Hsien Lu, et al. "Correlation between Executive Network Integrity and Sarcopenia in Patients with Parkinson’s Disease." International Journal of Environmental Research and Public Health 16, no. 24 (December 4, 2019): 4884. http://dx.doi.org/10.3390/ijerph16244884.
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Background: Sarcopenia is critically associated with morbidity and mortality in the progression of Parkinson’s disease (PD). However, analyses of clinical severity and brain changes, such as white matter (WM) alterations in PD patients with sarcopenia are limited. Further understanding of the factors associated with sarcopenia may provide a focused screen and potential for early intervention in PD patients. Methods: 52 PD patients and 19 healthy participants accepted dual-energy X-ray absorptiometry to measure the body composition. Using diffusion tensor imaging, the difference of WM integrity was measured between PD patients with sarcopenia (PDSa) and without sarcopenia (PDNSa). Multivariate analysis was performed to explore the relationships between clinical factors, WM integrity, and sarcopenia in PD patients. Results: 21 PD patients (40.4%) had sarcopenia. PDSa had a higher Unified Parkinson’s Disease Rating Scale (UPDRS III) score, lower body mass index (BMI) and lower fat weight compared with the PDNSa. Additionally, PDSa patients exhibited lower fractional anisotropy accompanied by higher radial diffusivity and/or higher mean diffusivity in the fronto-striato-thalamic circuits, including bilateral cingulum, left superior longitudinal fasciculus, left genu of corpus callosum, and right anterior thalamic radiation, which participate in the executive function. In addition, decreased muscle mass was associated with worse WM integrity in these regions. Multiple linear regression analysis revealed that WM integrity in the left cingulum, right anterior thalamic radiation, together with gender (male) significantly predicted muscle mass in PD patients. Conclusions: WM alterations in the executive network, such as the fronto-striato-thalamic circuits, may indicate a risk factor for ongoing sarcopenia in PD patients. The effectiveness of using executive function to serve as a prodromal marker of sarcopenia in PD patients should be evaluated in future studies.
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Minami, Noriaki, Donghyun Hong, Celine Taglang, Georgios Batsios, Anne Marie Gillepspie, Nicholas Stevers, Pavithra Viswanath, Joseph F. Costello, and Sabrina Ronen. "TMET-12. HYPERPOLARIZED Δ- [1-13C] GLUCONOLACTONE IMAGING VISUALIZES TERT-ASSOCIATED CHANGES IN DYNAMIC PENTOSE PHOSPHATE PATHWAY METABOLISM IN GLIOBLASTOMA." Neuro-Oncology 24, Supplement_7 (November 1, 2022): vii264. http://dx.doi.org/10.1093/neuonc/noac209.1017.
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Abstract BACKGROUND TERT promoter mutations are a hallmark of glioblastoma (GBM). We recently reported that the expression of TERT and its upstream transcriptional factor, GABPB1, are strongly correlated with redox in GBM with TERT promoter mutations. However, further imaging biomarkers which visualize redox-associated metabolism and TERT expression are needed. Here we demonstrate that 13C magnetic resonance spectroscopy (MRS) of hyperpolarized δ-[1-13C] gluconolactone metabolism is a useful imaging tool to visualize changes in dynamic pentose phosphate pathway (PPP) metabolism that reflect TERT-associated changes in redox in GBM. METHODS U251 human GBM cells stably expressing shRNA targeting TERT or GABPB1 were compared to controls. Doxycyclin-inducible shTERT or shGABPB1 U251 cells were also examined. For in vivo studies, cells were injected into immunodeficient rat brains and tumors confirmed by T2-weighted MRI. δ-[1-13C] gluconolactone was polarized using a Hypersense DNP polarizer and injected into live cells or tumor-bearing rats. For cells 13C-MRS was acquired using a 500MHz Agilent spectrometer and analyzed using Mnova and Matlab software. For in vivo13C-MRS studies, spectra were acquired using a 3T Bruker scanner and a spectral spatial echo-planar spectroscopic imaging sequence. Spectral signal to noise was improved using Tensor denoising. Spectra were processed using a custom-written Matlab script. RESULTS Hyperpolarized 6-phosphogluconolactone (6PG), the metabolic product from δ-[1-13C] gluconolactone via the PPP, was significantly reduced in TERT or GABPB1 silenced cells compared to control cells in both U251 models. The positive correlation between TERT expression and 6PG level was confirmed by linear regression analysis. Hyperpolarized 6PG production in both tumor models was also significantly reduced in TERT or GABPB1-silenced tumors compared to controls. CONCLUSION We successfully visualized TERT-associated changes in dynamic PPP metabolism in a GBM model in cells and in vivo. Hyperpolarized δ-[1-13C] gluconolactone is a potential tool for monitoring TERT expression in GBM with TERT promoter mutations.
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Matsushita, Makoto, Kohkichi Hosoda, Yasuo Naitoh, Haruo Yamashita, and Eiji Kohmura. "Utility of diffusion tensor imaging in the acute stage of mild to moderate traumatic brain injury for detecting white matter lesions and predicting long-term cognitive function in adults." Journal of Neurosurgery 115, no. 1 (July 2011): 130–39. http://dx.doi.org/10.3171/2011.2.jns101547.
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Object Traumatic brain injury (TBI) often impairs cognitive function. Diffusion tensor (DT) imaging, a novel modality, permits evaluation of the effects of head trauma on white matter nerve fibers. The objectives of the current study were to investigate where the white matter injury following mild to moderate TBI is specifically located on DT imaging in the acute disease stage and to examine the relationship between the severity of the white matter lesion on DT imaging in the acute stage of TBI and future cognitive function in the chronic disease stage. Methods Twenty adult patients with mild to moderate TBI (Glasgow Coma Scale score between 9 and 15) underwent conventional MR and DT imaging a median of 3.5 days after injury, and 27 matched healthy controls also underwent both imaging modalities. The patients with TBI were further subdivided into 2 groups, that is, mild and more severe TBI groups, based on clinical (mild or moderate TBI), CT (diffuse brain injury [DBI] I or II), or MR imaging (normal or pathological appearance) classification. Fractional anisotropies (FAs) were compared between patients and controls using the region of interest method. Regions of interest were located in 8 different areas including the genu, stem, and splenium of the corpus callosum and the corona radiata (CR), anterior limb of the internal capsule (ALIC), posterior limb of the internal capsule (PLIC), frontal white matter (FWM), and occipital white matter (OWM) of the periventricular white matter. Eleven patients with TBI also underwent neuropsychological testing, which included the Trail Making Test, Wisconsin Card Sorting Test, Wechsler Adult Intelligence Scale–Revised, and P300 testing in the chronic disease stage (median 364 days). Results Region of interest analysis demonstrated significantly lower FA values in the genu, stem, and splenium of the corpus callosum in more severe TBI groups (moderate TBI on clinical classification, DBI II on CT classification, and pathological appearance on MR imaging classification) than in controls. A significant difference was also observed in the FA of the splenium between controls and the mild TBI group of the clinical classification. No significant difference was observed in the FA of the CR, ALIC, PLIC, FWM, and OWM between controls and any of the TBI groups of clinical or imaging classifications. No significant difference was observed in the FA of any regions between mild and more severe TBI groups of the clinical or imaging classifications. Multiple regression analysis showed a statistically significant positive linear relationship between FA in the splenium and total IQ (r = 0.79, p = 0.004). A significant negative linear relationship between FA in the FWM and P300 latency was also observed (r = 0.62, p = 0.04). Conclusions Fractional anisotropy reductions in the splenium and FWM in the acute stage of mild to moderate TBI may be a useful prognostic factor for long-term cognitive dysfunction.
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Suleman, Marriam, and Ume Sughra. "Effect of Screen Time on Behavior of Preschoolers in Islamabad: Descriptive Cross-sectional Study." Iproceedings 8, no. 1 (February 11, 2022): e36568. http://dx.doi.org/10.2196/36568.
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Background The early years of childhood form the basis of intelligence, personality, social behavior, and the capacity to learn and nurture oneself as an adult. It is increasingly recognized that early and longer exposure to screens has adverse effects on the development of children. This research was significant in finding out the effects of screen time on the behavior of preschoolers, which could provide scientific grounds to the control of digital screen time. Objective We aimed to determine the effect of electronic exposure on the behavior, emotional development, and sleep quality of preschoolers and determine the average number of hours preschoolers spend with electronic devices in Islamabad. Methods A cross-sectional survey was conducted in 4 private preschools of Islamabad. A sample of 200 children aged 3 to 5 years was selected through multistage random sampling. The sociodemographic characteristics and screen time of the children were acquired by using parental questionnaires. Children were grouped based on a daily screen time of ≤60 minutes or >60 minutes. An analysis was conducted based on the results of the Child Behavior Checklist for children aged 1.5 to 5 years. The Cronbach α coefficient was found to be .925. It was analyzed by using SPSS version 22 (IBM Corporation). A chi-square test, an independent sample t test, and multilinear regression were applied to determine the associations and significance levels between the variables. Results The study results indicate that increased screen time was found to be statistically significant with regard to a child’s age, their education level, and the employment status of mothers. It was observed that preschoolers with a screen time of >60 minutes (mean 11.94, SD 3.91; P=.01) tend to more commonly experience withdrawn syndrome than those with a screen time of ≤60 minutes (mean 10.72, SD 3.01). Similarly, sleep problems were also more commonly observed in preschoolers with a screen time of >60 minutes (mean 10.97, SD 3.20; P=.01) when compared to those with a screen time ≤60 minutes (mean 9.90, SD 2.59). It was also observed that increased screen time had an association with autism spectrum problems among preschoolers with a screen time of >60 minutes (mean 17.66, SD 5.89; P=.047) when compared to those among preschoolers with a screen time of ≤60 minutes (mean 16.17, SD 4.58). The strongest predictor of the outcome variable was found to be mothers’ education level (ß=21.53). Conclusions The findings reveal that excessive screen time is a deleterious factor associated with the behavioral problems of preschoolers. Parents must also think about their child’s screen time. This requires parents’ active engagement and constant attention, so that the development and growth of their children are not affected adversely.
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El Jai, Mostapha, Mehdi Zhar, Driss Ouazar, Iatimad Akhrif, and Nourddin Saidou. "Socio-economic analysis of short-term trends of COVID-19: modeling and data analytics." BMC Public Health 22, no. 1 (August 29, 2022). http://dx.doi.org/10.1186/s12889-022-13788-4.
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Abstract Background COVID-19 caused a worldwide outbreak leading the majority of human activities to a rough breakdown. Many stakeholders proposed multiple interventions to slow down the disease and number of papers were devoted to the understanding the pandemic, but to a less extend some were oriented socio-economic analysis. In this paper, a socio-economic analysis is proposed to investigate the early-age effect of socio-economic factors on COVID-19 spread. Methods Fifty-two countries were selected for this study. A cascade algorithm was developed to extract the R0 number and the day J*; these latter should decrease as the pandemic flattens. Subsequently, R0 and J* were modeled according to socio-economic factors using multilinear stepwise-regression. Results The findings demonstrated that low values of days before lockdown should flatten the pandemic by reducing J*. Hopefully, DBLD is only parameter to be tuned in the short-term; the other socio-economic parameters cannot easily be handled as they are annually updated. Furthermore, it was highlighted that the elderly is also a major influencing factor especially because it is involved in the interactions terms in R0 model. Simulations proved that the health care system could improve the pandemic damping for low elderly. In contrast, above a given elderly, the reproduction number R0 cannot be reduced even for developed countries (showing high HCI values), meaning that the disease’s severity cannot be smoothed regardless the performance of the corresponding health care system; non-pharmaceutical interventions are then expected to be more efficient than corrective measures. Discussion The relationship between the socio-economic factors and the pandemic parameters R0 and J* exhibits complex relations compared to the models that are proposed in the literature. The quadratic regression model proposed here has discriminated the most influencing parameters within the following approximated order, DLBL, HCI, Elderly, Tav, CO2, and WC as first order, interaction, and second order terms. Conclusions This modeling allowed the emergence of interaction terms that don’t appear in similar studies; this led to emphasize more complex relationship between the infection spread and the socio-economic factors. Future works will focus on enriching the datasets and the optimization of the controlled parameters to short-term slowdown of similar pandemics.
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Etherton, Mark R., Ona Wu, Anne-Katrin Giese, and Natalia S. Rost. "Normal-appearing white matter microstructural injury is associated with white matter hyperintensity burden in acute ischemic stroke." International Journal of Stroke, December 17, 2019, 174749301989570. http://dx.doi.org/10.1177/1747493019895707.
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Background White matter hyperintensity of presumed vascular origin is a risk factor for poor stroke outcomes. In patients with acute ischemic stroke, however, the in vivo mechanisms of white matter microstructural injury are less clear. Aims To characterize the directional diffusivity components in normal-appearing white matter and white matter hyperintensity in acute ischemic stroke patients. Methods A retrospective analysis was performed on a cohort of patients with acute ischemic stroke and brain magnetic resonance imaging with diffusion tensor imaging sequences acquired within 48 h of admission. White matter hyperintensity volume was measured in a semi-automated manner. Median fractional anisotropy, mean diffusivity, radial diffusivity, and axial diffusivity values were calculated within normal-appearing white matter and white matter hyperintensity in the hemisphere contralateral to the acute infarct. Linear regression analysis was performed to evaluate predictors of white matter hyperintensity volume and normal-appearing white matter diffusivity metrics. Results In 319 patients, mean age was 64.9 ± 15.9 years. White matter hyperintensity volume was 6.33 cm3 (interquartile range 3.0–12.6 cm3). Axial and radial diffusivity were significantly increased in white matter hyperintensity compared to normal-appearing white matter. In multivariable linear regression, age (β = 0.20, P = 0.003) and normal-appearing white matter axial diffusivity (β = 37.9, P < 0.001) were independently associated with white matter hyperintensity volume. Subsequent analysis demonstrated that increasing age (β = 0.004, P < 0.001) and admission diastolic blood pressure (β = 0.001, P = 0.02) were independent predictors of normal-appearing white matter axial diffusivity in multivariable linear regression. Conclusions Normal-appearing white matter axial diffusivity increases with age and is an independent predictor of white matter hyperintensity volume in acute ischemic stroke.
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Toh, Cheng Hong, and Tiing Yee Siow. "Glymphatic Dysfunction in Patients With Ischemic Stroke." Frontiers in Aging Neuroscience 13 (November 8, 2021). http://dx.doi.org/10.3389/fnagi.2021.756249.
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Objectives: Rodent experiments have provided some insight into the changes of glymphatic function in ischemic stroke. The diffusion tensor image analysis along the perivascular space (DTI-ALPS) method offers an opportunity for the noninvasive investigation of the glymphatic system in patients with ischemic stroke. We aimed to investigate the changes of glymphatic function in ischemic stroke and the factors associated with the changes.Materials and Methods: A total of 50 patients (mean age 56.7 years; 30 men) and 44 normal subjects (mean age 53.3 years; 23 men) who had preoperative diffusion-tensor imaging for calculation of the analysis along the perivascular space (ALPS) index were retrospectively included. Information collected from each patient included sex, age, time since stroke onset, infarct location, hemorrhagic change, infarct volume, infarct apparent diffusion coefficient (ADC), infarct fractional anisotropy (FA), and ALPS index of both hemispheres. Interhemispheric differences in ALPS index (infarct side vs. contralateral normal side) were assessed with a paired t-test in all patients. ALPS index was normalized by calculating ALPS ratios (right-to-left and left-to-right) for comparisons between patients and normal subjects. Comparisons of ALPS ratios between patients and normal subjects were performed using analysis of covariance with adjustments for age and sex. Linear regression analyses were performed to identify factors associated with the ALPS index.Results: In patients, the mean ALPS index ipsilateral to infarct was 1.162 ± 0.126, significantly lower (P < 0.001) than that of the contralateral side (1.335 ± 0.160). The right-to-left ALPS index ratio of patients with right cerebral infarct was 0.84 ± 0.08, significantly lower (P < 0.001) than that of normal subjects (0.95 ± 0.07). The left-to-right ALPS ratio of patients with left cerebral infarct was 0.92 ± 0.09, significantly (P < 0.001) lower than that of normal subjects (1.05 ± 0.08). On multiple linear regression analysis, time since stroke onset (β = 0.794, P < 0.001) was the only factor associated with the ALPS index.Conclusion: The ALPS index showed lower values in ischemic stroke suggesting impaired glymphatic function. Following initial impairment, the ALPS index increased with the time since stroke onset, which is suggestive of glymphatic function recovery.
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Spagnolo-Allende, Antonio, Rebecca Schnall, Minghua Liu, Krystal K. Laing, Kay C. Igwe, Adam Brickman, and Jose Gutierrez. "Abstract WMP21: Blood Biomarkers Of Endothelial And Macrocytic Activation Are Associated With Brain White Matter Microstructure In People Living With Hiv On Antiretroviral Treatment." Stroke 53, Suppl_1 (February 2022). http://dx.doi.org/10.1161/str.53.suppl_1.wmp21.
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Objective: To identify associations between specific serum inflammatory markers and structural white matter integrity as measured on brain diffusion tensor imaging (DTI) in middle-aged people living with HIV (PLWH). Methods: PLWH over 50 years of age residing in New York, NY participated in a cross-sectional study between January and July 2019. Demographic and magnetic resonance imaging data, along with blood samples, were collected. Least absolute shrinkage and selection operator (LASSO) regression was used to identify the most relevant variables associated with brain white matter fractional anisotropy (FA) and mean diffusivity (MD), among seventeen serum inflammatory markers, and control variables (listed in Table 1). Results: A total of 85 PLWH were included in the analysis. Mean age (SD) was 60 (6) years, 48% were men and 78% non-Hispanic black. All were taking antiretroviral therapy at enrollment. Among them, 75% had CD4 count ≥200 cell/mm 3 and viral load <400 copies/mL near the time of their MRI scans. We observed that, as the penalty factor (λ) increased in the LASSO regression, vascular endothelial growth factor (VEGF) (β=-0.052), monocyte chemoattractant protein 1 (MCP-1) (β=-0.001) and macrophage inflammatory proteins 1α (MIP-1α) (β=-0.007) and 1β (MIP-1β) (β=-0.074) remained in the LASSO model for FA. Similarly, VEGF (β=1.01x10 -4 ), MIP-1α (β=3.67x10 -6 ) and MIP-1β (β=7.12x10 -5 ) remained in the LASSO model for MD (Table 1). Conclusion: Prior research has linked VEGF to HIV-associated encephalopathy and MCP-1 to HIV-associated dementia, while both MIP-1α and MIP-1β have been associated with asymptomatic HIV infection. Our findings therefore may offer a mechanistic framework for those associations, indicating that chronic inflammation in the context of HIV infection may alter brain white matter microstructure. Such alterations may contribute to the development of HIV-associated central nervous system disorders.
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Liu, Juan, Zhuang Liu, Yange Wei, Yanbo Zhang, Fay Y. Womer, Duan Jia, Shengnan Wei, et al. "Combinatorial panel with endophenotypes from multilevel information of diffusion tensor imaging and lipid profile as predictors for depression." Australian & New Zealand Journal of Psychiatry, May 27, 2022, 000486742110314. http://dx.doi.org/10.1177/00048674211031477.
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Objective: Clinical heterogeneity in major depressive disorder likely reflects the range of etiology and contributing factors in the disorder, such as genetic risk. Identification of more refined subgroups based on biomarkers such as white matter integrity and lipid-related metabolites could facilitate precision medicine in major depressive disorder. Methods: A total of 148 participants (15 genetic high-risk participants, 57 patients with first-episode major depressive disorder and 76 healthy controls) underwent diffusion tensor imaging and plasma lipid profiling. Alterations in white matter integrity and lipid metabolites were identified in genetic high-risk participants and patients with first-episode major depressive disorder. Then, shared alterations between genetic high-risk and first-episode major depressive disorder were used to develop an imaging x metabolite diagnostic panel for genetically based major depressive disorder via factor analysis and logistic regression. A fivefold cross-validation test was performed to evaluate the diagnostic panel. Results: Alterations of white matter integrity in corona radiata, superior longitudinal fasciculus and the body of corpus callosum and dysregulated unsaturated fatty acid metabolism were identified in both genetic high-risk participants and patients with first-episode major depressive disorder. An imaging x metabolite diagnostic panel, consisting of measures for white matter integrity and unsaturated fatty acid metabolism, was identified that achieved an area under the receiver operating characteristic curve of 0.86 and had a significantly higher diagnostic performance than that using either measure alone. And cross-validation confirmed the adequate reliability and accuracy of the diagnostic panel. Conclusion: Combining white matter integrity in corpus callosum, superior longitudinal fasciculus and corona radiata, and unsaturated fatty acid profile may improve the identification of genetically based endophenotypes in major depressive disorder to advance precision medicine strategies.
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Li, Xinghui, Qi Liang, Erika Ouchi, Matthew Bautista, Jiani Hu, and XiaoMing Zhan. "Using Multi-model Diffusion Weighted Imaging to Study Acute Kidney Injury in Patients with Acute Pancreatitis." Current Medical Imaging Formerly Current Medical Imaging Reviews 19 (January 30, 2023). http://dx.doi.org/10.2174/1573405619666230130123138.
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Objective: To explore the diagnostic value and severity of acute kidney injury (AKI) in patients with acute pancreatitis (AP) using intravoxel incoherent motion imaging (IVIM), diffusion tensor imaging (DTI), and diffusion kurtosis imaging (DKI). Methods: 224 AP patients, categorized into either the AKI group or the non-AKI group, were retrospectively analyzed in this study. MRI sequences included routine abdominal, IVIM, DTI, and DKI scans, and the main MRI parameters of kidney imaging and clinical characteristics were measured. The diagnostic performance of AKI was compared, and the relationships among these indices, glomerular filtration rate (eGFR), and AKI staging were analyzed. Finally, all parameters were analyzed by single and multi-parameter regression. Results: Compared with the non-AKI group, the fast apparent diffusion coefficient (ADC) value and perfusion fraction (Ff ADC) value of the renal medulla in the AKI group were significantly lower than those in the non-AKI group. The fractional anisotropy (FA) value in the renal cortex was significantly lower than that in the medulla and significantly lower than in the non-AKI group. Lastly, the renal medulla mean kurtosis (MK) value was also significantly lower in the AKI group compared to the non-AKI group and exhibited the best diagnostic value for AKI in AP patients. The renal medulla MK value positively correlated with AKI staging and negatively correlated with eGFR. The MK value was an independent risk factor for AKI, as evidenced by multi-parameter logistic regression analysis. Conclusion: The measurement of renal DKI parameters is practical for diagnosing and predicting the severity of acute kidney injury in AP patients.
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Esposito, L., R. Sorrentino, V. Capone, C. Santoro, M. Lembo, R. Esposito, F. Lo Iudice, A. M. De Roberto, A. Tufano, and M. Galderisi. "P814 Independent association of body mass index and left atrial strain in patients with non valvular atrial fibrillation. The NeAfib-Echo registry." European Heart Journal - Cardiovascular Imaging 21, Supplement_1 (January 1, 2020). http://dx.doi.org/10.1093/ehjci/jez319.467.
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Abstract Background Overweight and obesity are related to the risk of new-onset atrial fibrillation (AF). Peak atrial longitudinal strain (PALS) is an advanced echocardiographic parameter of left atrial (LA) function with a recognized diagnostic and prognostic role in both the general population and AF. Purpose To investigate the impact of body mass index (BMI) on LA function by utilizing standard and advanced echocardiography in patients with non-valvular AF. Methods In the NeAfib-Echo registry, 395 consecutive adult patients with non-valvular AF (F/M: 175/220; mean age 70.6 ± 11 years, BMI: 27.8 ± 5.6 kg/m²) were enrolled. 215 patients (54.1%) had permanent/persistent AF (prAF) and 178 (45.9%) had paroxysmal AF (pxAF). Anthropometric parameters and blood pressure (BP) were recorded and CHA2DS2VASc score was calculated. Patients underwent a complete echo-Doppler exam, including determination of PALS and left ventricular (LV) global longitudinal strain (GLS) (both reported in absolute values). The overall population was divided according to BMI tertiles: first tertile <25.3 Kg/m² (n = 127); second tertile 25.3-29 Kg/m² (n = 137); third tertile > 29.3 Kg/m² (n = 130). Results No significant difference of sex prevalence, age, systolic BP and heart rate was found among the three BMI tertiles, whereas diastolic BP was higher in the third tertile (p < 0.001). CHA2DS2VASc score did not significantly differ among tertiles. In the pooled population LV mass index (LVMi) (p = 0.001) progressively increased from the first to the third tertile (p < 0.001), whereas LA volume index, LV ejection fraction (EF), GLS and E/e" ratio were not significantly different among the three groups. PALS was lower in third tertile (14.3 ± 8.2%) versus both the first (19.0 ± 11.5%) and the second tertile (17.7 ± 10.6%) (p < 0.002). In separate sub-analyses according to AF type, PALS was significantly lower in the first than the third tertile in the PxAF group (p < 0.01) but not in patients with PrAF (p = 0.158). In the pooled population PALS was significantly related with BMI (r= -0.17, p < 0.001) (Figure) but also with age, heart rate, LVMi, LV EF, GLS, E/e’ ratio and pulmonary artery systolic pressure (PAPS). By a multilinear regression analysis, after adjusting for CHA2DS2VASc score, LV mass index, LV EF, E/e’ ratio and PAPs, BMI remained independently associated with PALS (standardized β coefficient = -0.127, p < 0.02) (cumulative R² =0.41, SEE = 8.5%, p < 0.0001). Conclusions In patients with non valvular AF, overweight and obesity exert a detrimental effect on LA function as testified by the gradual PALS reduction with the increase of BMI tertiles. BMI is associated with PALS independently of several confounders including CHA2DS2VASc. Besides CHA2DS2VASc score, BMI could be considered as an additional factor for evaluating cardiovascular risk in non valvular AF. Abstract P814 Figure. Relation between BMI and PALS