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Introduction: Primary leiomyosarcoma (LMS) of the colon is a rare neoplasm and constitutes less than 0.1% of all colon malignancies. These tumors are more aggressive and have poorer prognoses than other gastrointestinal tumors, including gastrointestinal stromal tumors (GIST) or adenocarcinomas. The authors herein report two cases and review the literature to highlight the epidemiology, diagnosis, treatment and prognosis of this uncommon malignancy. Case report: The authors reported two very rare cases of LMS of left colon, which referred to our institution with symptoms of abdominal pain. After the initial investigations, patients were diagnosed with primary colonic leiomyosarcoma that underwent laparotomy. In both cases pathological examination revealed a spindle cell tumor growing circumferentially and transmurally in the colon. Final immunohistochemistry were positive with SMA, CK and desmin without the expression of GIST markers (CD117, CD34 and DOG1) that confirmed leiomyosarcoma. One patient was diagnosed with diffused peritoneal metastasis at 6 months postoperatively and he died after 2 months of paliative care, another one is still on active surveillance. Discussion: LMS of the colon is a really rare entity and is only presented in clinical case reports. LMS has non-specific symptoms and is commonly diagnosed when it reaches a large size. Surgery is a mainstay treatment option. Nowadays, there is no clear evidence for the effectiveness of chemotherapy and radiation therapy. Conclusion: LMS is a rare neoplasm of colon. For the time being, there is no guidelines for treatment, but surgery still plays a fundamental role.
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BACKGROUND: Gene expression can provide distinct information compared to clinical biomarkers in the context of longitudinal clinical outcomes in asthma patients. OBJECTIVE: This study examined the association between the gene expression levels of upstream (IL-25, IL-33, and TSLP) and downstream cytokines (IL-5, IL-4, and IL-13) in the T2 inflammatory pathway with a 12-month follow-up of exacerbation, lung function, and steroid use. METHODS: Transcriptomic sequencing analysis was performed on peripheral blood mononuclear cells from 279 adult asthmatics. Survival analysis and linear mixed-effect models were used to investigate potential differences between the high-level and low-level gene expression groups and the clinical outcomes. Analysis was performed separately for the upstream, downstream, and all 6 cytokines. RESULTS: In general, T2 inflammatory cytokine gene expression showed a weak correlation with blood eosinophil counts (all r < 0.1) and clinical outcomes. Among moderate-to-severe eosinophilic asthma (MSEA) patients, individuals with elevated levels of downstream cytokines were at increased risk of time-to-first exacerbation (p = 0.044) and a greater increase of inhaled corticosteroid use over time (p = 0.002) compared to those with lower gene expression. There was no association between baseline T2 inflammatory cytokine gene expression and the longitudinal changes in lung function over time among MSEA patients. CONCLUSION: These findings suggest that, among MSEA patients, the gene expression levels of downstream cytokines in the T2 inflammatory pathway may serve as indicators for endotyping asthma.
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Asthma , Cytokines , Interleukin-13 , Interleukin-4 , Leukocytes, Mononuclear , Transcriptome , Humans , Asthma/genetics , Asthma/blood , Asthma/immunology , Asthma/drug therapy , Male , Female , Leukocytes, Mononuclear/metabolism , Adult , Middle Aged , Cytokines/genetics , Cytokines/blood , Longitudinal Studies , Interleukin-4/genetics , Interleukin-4/blood , Interleukin-13/genetics , Interleukin-13/blood , Eosinophils , Thymic Stromal Lymphopoietin , Interleukin-5/genetics , Interleukin-5/blood , Interleukin-33/genetics , Interleukin-33/blood , Interleukin-17/genetics , Interleukin-17/blood , Adrenal Cortex Hormones/therapeutic use , Gene Expression Profiling/methods , Disease Progression , Severity of Illness IndexABSTRACT
Light-matter interaction between quantum emitters and optical cavities plays a vital role in fundamental quantum photonics and the development of optoelectronics. Resonant metasurfaces are proven to be an efficient platform for tailoring the spontaneous emission (SE) of the emitters. In this work, we study the interplay between quasi-2D perovskites and dielectric TiO2 metasurfaces. The metasurface, functioning as an open cavity, enhances electric fields near its plane, thereby influencing the emissions of the perovskite. This is verified through angle-resolved photoluminescence (PL) studies. We also conducted reflectivity measurements and numerical simulations to validate the coupling between the quasi-2D perovskites and photonic modes. Notably, our work introduces a spatial mapping approach to study Purcell enhancement. Using fluorescence lifetime imaging microscopy (FLIM), we directly link the PL and lifetimes of the quasi-2D perovskites in spatial distribution when positioned on the metasurface. This correlation provides unprecedented insights into emitter distribution and emitter-resonator interactions. The methodology opens a new (to the best of our knowledge) approach for studies in quantum optics, optoelectronics, and medical imaging by enabling spatial mapping of both PL intensity and lifetime, differentiating between uncoupled quantum emitters and those coupled with different types of resonators.
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OBJECTIVES: Depression in medical students is concerning, potentially fueled by many stressors including career choice-relating stress. Choosing Medicine is a life-long commitment, and low intrinsic motivation or excessive dependence on family can complicate this decision and adding stress throughout their training. This stress intensifies in the final year, as students lacking personal drive struggle to see themselves continuing the career. Given limited studies on this crucial topic in Asia and Vietnam, we explored direct linkage between career choice motivation and depression in final-year medical students. METHODS: A cross-sectional study was conducted with 569 final-year students between June and July 2020. The Vietnamese Patient Health Questionnaire 9 (PHQ-9) and 16-item CCM questionnaire were used as survey tools. Univariate analysis was used for descriptive statistics (absolute and relative frequency, mean (M), standard deviation (SD). Multinomial logistic regression models were used to explore the relationship between variables using STATA 5.1. RESULTS: The depression among participants was about 24.6% (PHQ-9 cut-off ≥ 12). No difference in gender was found regarding depression. The most acknowledged motivator is securing employment (M = 4.14, SD = 1.02) and the least is parental wishes (M = 3.17, SD = 1.32). Familial influence on career choice significantly increased odds of having "moderately-severe depression" (OR = 1.17, 95% CI 1.04-1.32) and "severe depression" (OR = 1.36, 95% CI 1.10-1.68), whereas, career-choice motivators including satisfaction (OR = .76, 95% CI .60-.97), self-competence (OR = .80, 95% CI .66-.97) and career success (OR = .84, 95% CI .71-.99) were found to be protective factors for depression. CONCLUSIONS: Roughly a quarter of final-year medical students encountered depression. Occupational security ranked as the primary motivator, with parental wish being the least. Familial influence heightened depression risk, while career prospects, satisfaction and self-efficacy acted as protective factors. Medical career paths should align with intrinsic motivations and personal interests for better mental health outcomes.
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BACKGROUND: The determinants linked to the short- and long-term improvement in lung function in patients with severe eosinophilic asthma (SEA) on biological treatment (BioT) remain elusive. OBJECTIVE: We sought to identify the predictors of early and late lung function improvement in patients with SEA after BioT. METHODS: 140 adult patients with SEA who received mepolizumab, dupilumab, or reslizumab were followed up for 6 months to evaluate improvement in forced expiratory volume in one second (FEV1). Logistic regression was used to determine the association between potential prognostic factors and improved lung function at 1 and 6 months of treatment. RESULTS: More than a third of patients with SEA using BioT showed early and sustained improvements in FEV1 after 1 month. A significant association was found between low baseline FEV1 and high blood eosinophil count and sustained FEV1 improvement after 1 month (0.54 [0.37-0.79] and 1.88 [1.28-2.97] odds ratios and 95% confidence interval, respectively). Meanwhile, among patients who did not experience FEV1 improvement after 1 month, 39% exhibited improvement at 6 months follow-up. A high ACT score measured at this visit was the most reliable predictor of late response after 6 months of treatment (OR and 95% CI 1.75 [1.09-2.98]). CONCLUSION: Factors predicting the efficacy of biological agents that improve lung function in SEA vary according to the stage of response.
Subject(s)
Anti-Asthmatic Agents , Asthma , Biological Products , Pulmonary Eosinophilia , Adult , Humans , Anti-Asthmatic Agents/therapeutic use , Biological Products/therapeutic use , Eosinophils , Pulmonary Eosinophilia/drug therapy , LungABSTRACT
BACKGROUND: Although various monoclonal antibodies have been used as add-on therapy for severe eosinophilic asthma (SEA), to the best of our knowledge, no direct head-to-head comparative study has evaluated their efficacy. OBJECTIVE: To compare the efficacy of reslizumab, mepolizumab, and dupilumab in patients with SEA. METHODS: This was a multicenter, prospective observational study in patients with SEA who had received 1 of these biologic agents for at least 6 months. Cox proportional hazard models were used to compare the risk of the first exacerbation event, adjusting for sputum or blood eosinophils and common asthma-related covariates. The annual exacerbation rate was analyzed using a negative binomial model, and a mixed-effect model was used to analyze changes in forced expiratory volume in 1 second and asthma control test score over time. RESULTS: A total of 141 patients with SEA were included in the analysis; 71 (50%) received dupilumab; 40 (28%) received reslizumab, and 30 (21%) received mepolizumab. During the 12-month follow-up, 27.5%, 43.3%, and 38.0% of patients in the reslizumab, mepolizumab, and dupilumab groups, respectively, experienced at least 1 exacerbation. However, after adjusting for confounding factors, the dupilumab and mepolizumab groups showed similar outcomes in time-to-first exacerbation, exacerbation rate, forced expiratory volume in 1 second, and asthma control test score to those of the reslizumab group. CONCLUSION: In patients with SEA, treatment with reslizumab, mepolizumab, and dupilumab resulted in comparable clinical outcomes within a 12-month period. TRIAL REGISTRATION: The cohort protocol was sanctioned by the Institutional Review Board of each study center (clinicaltrial.gov identifier NCT05164939).
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Anti-Asthmatic Agents , Asthma , Biological Products , Pulmonary Eosinophilia , Humans , Prospective Studies , Eosinophils , Antibodies, Monoclonal/therapeutic use , Pulmonary Eosinophilia/drug therapy , Biological Products/therapeutic use , Anti-Asthmatic Agents/therapeutic useABSTRACT
This paper presents an algorithm for ultrafast ultrasound localization microscopy (ULM) used for the detection, localization, accumulation, and rendering of intravenously injected ultrasound contrast agents (UCAs) enabling to yield hemodynamic maps of the brain microvasculature. It consists in integrating a robust principal component analysis (RPCA)-based approach into the ULM process for more robust tissue filtering, resulting in more accurate ULM images. Numerical experiments conducted on an in vivo rat brain perfusion dataset demonstrate the efficiency of the proposed approach compared to the most widely used state-of-the-art method.
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Brain , Microscopy , Rats , Animals , Microscopy/methods , Principal Component Analysis , Brain/diagnostic imaging , Brain/blood supply , Contrast Media , Ultrasonography/methodsABSTRACT
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The proposed carbon peak and carbon neutralization goals have ushered China into an era of emissions reduction and a climate-oriented economy. With the proposed double carbon goal, China has formulated many environmental protection and green credit policies. This paper aims to assess the impact of corporate environmental performance (CEP) on financing costs, using a panel dataset of companies in China's heavily polluting industries from 2010 to 2019. We employed fixed-effect models, moderating-effect models, and panel quantile regression (PQR) to analyze the impact, underlying mechanisms, and asymmetric features of CEP on financing costs. Our results indicate that CEP has an inhibitory effect on financing costs, with political connections strengthening this effect and GEA weakening it. Moreover, the impact exhibits asymmetry at different levels of financing costs, wherein lower financing costs see a greater weakening effect from CEP. Improved CEP helps to optimize the financing performance of companies and reduce financing costs. Therefore, policy makers and regulatory authorities should work to unblock financing channels for companies, encourage environmental investment, and remain flexible in implementing environmental policies.
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Administrative Personnel , Carbon , Humans , China , Climate , Environmental PolicyABSTRACT
Purpose@#The purpose of this study is to analyze the prognostic factors related to tooth loss after 5 years of periodontal surgery in periodontal disease patients. @*Materials and Methods@#From January to December 2017, 22 patients and 124 teeth who underwent periodontal treatment through periodontal surgery were targeted. At the time of treatment, the measured values were evaluated after recording the maximum probing depth, average periodontal probing depth, number of root, furcation involvement, pulp vitality, and prosthesis state on the day of periodontal surgery. Based on the initial records at the time of visit, patient-related factors were gender, age, smoking, tooth loss due to periodontal disease at the time of first visit, diabetes, and maintenance period.The influence of each factor on tooth loss was evaluated. @*Results@#As a result of examining the influence of tooth-related factors on tooth loss, the maximum probing depth depth (P: 0.000), bone loss (P: 0.021) was found to have a significant effect on tooth loss. @*Conclusion@#As a result of examining the influence of patient-related factors on tooth loss, any variables had no significant effect.Bone loss, maximum probing depth acted as statistically significant prognostic factors for tooth loss in patients who underwent periodontal surgery.
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PURPOSE: Blood (EOS-B) and sputum (EOS-S) eosinophil counts may contribute differently to asthma pathogenesis. We compared the impact of the baseline EOS-B and EOS-S levels on lung function, asthma control, and exacerbation in Korean asthma patients. METHODS: Asthma patients with baseline EOS-B (n = 4257) and EOS-S (n = 1049) levels from a multicenter cohort (COREA) were included. Pulmonary function test (%FEV1 predicted), asthma control test (ACT), and asthma exacerbation incidence were followed-up every 3 months for one year. Linear mixed-effect models and survival analyses were used to examine the association between eosinophilic groups defined by EOS-B or EOS-S and outcomes. RESULTS: High eosinophilic groups were associated with a low baseline value and a high improvement in the %FEV1 predicted and ACT scores over time. The magnitude of group difference in %FEV1 predicted was twofold higher in the EOS-S versus EOS-B classification [mean and 95% CI: 4.7 (0.6-8.8) versus 2.0 (0.2-3.7) for the baseline value and - 1.5 (- 2.3 to - 0.8) versus - 0.8(- 1.1 to -0.4) for the slope of change], whereas it was identical in ACT score. The magnitude of the impact increased linearly with the elevation of the cut-off level for the EOS-B but remained stable for the EOS-S classification. Patients with an elevation of both their EOS-B and EOS-S showed a higher increment in the %FEV1 predicted and ACT over time. Neither the EOS-B nor EOS-S was associated with asthma exacerbation. CONCLUSION: EOS-S and EOS-B contribute differently to the clinical outcomes and should be taken into account independently to improve asthma care.
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Asthma , Eosinophils , Humans , Eosinophils/pathology , Sputum , Respiratory Function Tests , Leukocyte Count , LungABSTRACT
We studied niobium nitride (NbN)-based π-junctions with a diluted ferromagnetic Pd89Ni11 interlayer (NbN/PdNi/NbN junctions). In the NbN/PdNi/NbN junctions with various PdNi thicknesses, we observed a non-monotonic dependence of the critical currents on PdNi thickness, indicating the effects of the exchange interaction on the superconducting order parameter. From theoretical fitting of the experimental data, we found that the NbN/PdNi/NbN junctions showed a significantly smaller degree of spin-flip scattering in the PdNi interlayer than in the CuNi interlayer of NbN/CuNi/NbN junctions reported previously. The weak spin-flip scattering leads to a longer decay length of the Josephson critical current, so the critical currents were observed over a wide range of PdNi thicknesses (10-40 nm). We also fabricated superconducting quantum interference devices (SQUIDs) including the NbN/PdNi/NbN junction, using a PdNi thickness in which the π-state was expected. A half-flux-quantum shift, as evidence of the π-state, was observed in the magnetic field-dependent critical currents of the SQUIDs. This result represents an important step towards the practical application of NbN-based π-Josephson junctions.
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CONTEXT: The effect of baseline (B) and alteration of metabolic parameters (MPs), including plasma glucose (PG) testing, insulin resistance surrogates, and lipid profile and their mutual interactions on the development of type 2 diabetes mellitus (T2DM), has not been investigated systematically. OBJECTIVE: To access the association of the past variability (V), past mean (M), and B values of various MPs and their mutual interaction with the risk of T2DM. METHODS: A community-based, longitudinal analysis was conducted using the Korean Genome and Epidemiology Study comprising 3829 nondiabetic participants with completed MPs measurements during 3 biannually visits who were followed over the next 10 years. Outcomes included the incidence of T2DM during follow-up. RESULTS: Among predictors, PG concentrations measured during the oral glucose tolerance test were the most prominent T2DM determinants, in which the M of the average value of fasting PG (FPG), 1-hour, and 2-hour PGs had the strongest discriminative power (hazard ratios and 95% CI for an increment of SD: 3.00 (2.5-3.26), AUC: 0.82). The M values of MPs were superior to their B and V values in predicting T2DM, especially among postload PGs. Various mutual interactions between indices and among MPs were found. The most consistent interactants were the M values of high-density lipoprotein cholesterol and the M and V values of FPG. The findings were similar in normal glucose tolerance participants and were confirmed by sensitivity analyses. CONCLUSION: Postload PG, past alteration of measurements, and mutual interactions among indices of MPs are important risk factors for T2DM development.
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Diabetes Mellitus, Type 2 , Insulin Resistance , Blood Glucose/metabolism , Diabetes Mellitus, Type 2/epidemiology , Diabetes Mellitus, Type 2/etiology , Fasting , Glucose Tolerance Test , Humans , Risk FactorsABSTRACT
BACKGROUND: Educators play a critical role in offering knowledge that is vital to preventing the spread of the COVID-19 in educational settings. This study aims to assess the proportion of preventive practices towards COVID-19 and associated factors among educators in Vietnam. METHODS: A cross-sectional study was conducted on educators at the University of Medicine and Pharmacy at Ho Chi Minh City (UMP) using a self-administered questionnaire between June and August 2020. Online surveys and a multivariable logistic regression analysis were used to determine factors associated with practices. Adjusted odds ratio (AOR) and 95% confidence interval (95% CI) were performed using Stata 14. RESULTS: A total of 779 eligible participants were approached, most of them under 50 years (84.1%), around three-fifth were female (61.0%) and lecturers (61.1%), with only 38.1% of them working at hospitals. Overall, the majority of participants had good preventive practices towards COVID-19 (88.6%). Factors identified as being associated with good practices included participants who are lecturers (AOR 1.8, 95% CI: 1.05-2.97), attending training courses related to COVID-19 (AOR 1.7, 95% CI: 1.05-2.87), working at hospitals (AOR 2.5, 95% CI: 1.28-4.76) and having a higher level of knowledge and attitude relating to COVID-19 (AOR 2.8, 95% CI: 1.52-5.17; AOR 2.8, 95% CI: 1.70-4.48, respectively) (all p < 0.05). CONCLUSION: These findings revealed that most educators reported a good level of preventive practices towards COVID-19. However, lower levels of practices still exist towards COVID-19 among participants who were administrative staff and have less access to training courses related to COVID-19, who reported that they did not work at the hospital and had a lower level of knowledge and attitude related to COVID-19. Because of the important role of educators in the education system, this study is expected to help education and health authorities implement suitable interventions to fill the gaps in practices between educators.
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PURPOSE: Health science students need to be professional to improve quality of care (QOC) in the current Vietnamese healthcare system. Therefore, we aim to evaluate medicine and traditional medicine (TM) students' perception of the professional attributes relating to QOC for improving inter-disciplined professionalism training that promotes QOC in Vietnam. METHODS: The cross-sectional study was carried on 2039 students of 6 years at the University of Medicine and Pharmacy at Ho Chi Minh City (HUMP) from the medical and TM faculty in March, 2021. The Vietnamese American Board of Internal Medicine (ABIM) questionnaire (2011) was used as the survey instrument. The confirmatory factor analysis (CFA) was performed to confirm the validity of the scale in TM students. Mean, Min-Max, standard deviation and sample paired t-test were performed for Likert scale. The one-way ANOVA was used for inferential statistics. RESULTS: The CFA demonstrated the validity of the Vietnamese questionnaire in measuring 4 QOC-relating professional attributes, previously found in medical students for TM students. In both faculties and across academic years, students perceived self-awareness and ensuring QOC as the leading important attribute, while social duty and professional habit as the least important attribute. Contrasting with preclinical phase, students' perception did not differ significantly between the two faculties in their clinical years (p > 0.05). CONCLUSION: TM students share universal QOC-relating professional traits with medical students. Moreover, exposure to clinical environment might increase inter-disciplined agreement on importance of these attributes. However, health sciences students' underestimation of social duty and professional habit persists throughout 6 academic years. Hidden curriculum in clinical training such as specialist-centeredness might hinder the students' improvement in perception of these traits. Therefore, these traits should strongly be emphasized in professionalism training to decrease the effects of hidden curriculum on them.
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Highly methylated Long Interspersed Nucleotide Elements 1 (LINE-1) constitute approximately 20% of the human genome, thus serving as a surrogate marker of global genomic DNA methylation. To date, there is still lacking a consensus about the precise location in LINE-1 promoter and its methylation threshold value, making challenging the use of LINE-1 methylation as a diagnostic, prognostic markers in cancer. This study reports on a technical standardization of bisulfite-based DNA methylation analysis, which ensures the complete bisulfite conversion of repeated LINE-1 sequences, thus allowing accurate LINE-1 methylation value. In addition, the study also indicated the precise location in LINE-1 promoter of which significant variance in methylation level makes LINE-1 methylation as a potential diagnostic biomarker for lung cancer. A serial concentration of 5-50-500 ng of DNA from 275 formalin-fixed paraffin-embedded lung tissues were converted by bisulfite; methylation level of two local regions (at nucleotide position 300-368 as LINE-1.1 and 368-460 as LINE-1.2) in LINE-1 promoter was measured by real time PCR. The use of 5 ng of genomic DNA but no more allowed to detect LINE-1 hypomethylation in lung cancer tissue (14.34% versus 16.69% in non-cancerous lung diseases for LINE-1.1, p < 0.0001, and 30.28% versus 32.35% for LINE-1.2, p < 0.05). Our study thus highlighted the optimal and primordial concentration less than 5 ng of genomic DNA guarantees the complete LINE-1 bisulfite conversion, and significant variance in methylation level of the LINE-1 sequence position from 300 to 368 allowed to discriminate lung cancer from non-cancer samples.
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Biomarkers, Tumor/metabolism , DNA, Neoplasm/metabolism , Epigenesis, Genetic , Long Interspersed Nucleotide Elements , Lung Neoplasms/diagnosis , Sulfites/chemistry , Aged , Biomarkers, Tumor/genetics , Case-Control Studies , DNA Methylation , DNA, Neoplasm/genetics , Female , Formaldehyde/chemistry , Humans , Lung Neoplasms/genetics , Lung Neoplasms/metabolism , Lung Neoplasms/pathology , Male , Microtomy/methods , Middle Aged , Paraffin Embedding/methods , Promoter Regions, Genetic , Tissue Fixation/methodsABSTRACT
AIMS: The fasting, 1-h, and 2-h plasma glucose (PG) levels during oral glucose tolerance test represent different glucose metabolic functions. We examined whether averaging these PG indices (GLUM0.60.120) results in a better predictor of future type 2 diabetes (T2DM). METHODS: 7533 participants were followed up biannually for 12 years. Hazard ratios (HRs), area under the curve (AUC) of the receiver-operating characteristic, and the net reclassification index (NRI) for T2DM were calculated to compare the discriminative ability of GLUM0.60.120 versus other PG indices. RESULTS: The adjusted HRs and 95% confidence intervals for an increase in SD of GLUM0.60.120 was 2.50 (2.36-2.65) and 1.88 (1.73-2.04) in T2DM-free and normal glucose tolerance (NGT) participants, respectively. The AUC of GLUM0.60.120 was higher than that of fasting PG, 1-h, and 2-h PG values for T2DM-free (0.79 versus 0.67, 0.77, and 0.73) and NGT (0.73 versus 0.65, 0.72, and 0.61). The model using GLUM0.60.120 improved the classification of the models with fasting PG, 1-h, and 2-h PG values (NRI: 0.369, 0.272, and 0.282 for T2DM-free and 0.249, 0.131, and 0.351 for NGT participants with all p < 0.001). CONCLUSIONS: The mean of fasting, 1-h, and 2-h PG levels predicts future T2DM better than each index.
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Blood Glucose/metabolism , Diabetes Mellitus, Type 2/blood , Fasting/blood , Female , Humans , Male , Middle AgedABSTRACT
This article addresses the problem of high-resolution Doppler blood flow estimation from an ultrafast sequence of ultrasound images. Formulating the separation of clutter and blood components as an inverse problem has been shown in the literature to be a good alternative to spatio-temporal singular value decomposition (SVD)-based clutter filtering. In particular, a deconvolution step has recently been embedded in such a problem to mitigate the influence of the point spread function (PSF) of the imaging system. Deconvolution was shown in this context to improve the accuracy of the blood flow reconstruction. However, the PSF needs to be measured experimentally, and measuring it requires nontrivial experimental setups. To overcome this limitation, we propose herein a blind deconvolution method able to estimate both the blood component and the PSF from Doppler data. Numerical experiments conducted on simulated and in vivo data demonstrate qualitatively and quantitatively the effectiveness of the proposed approach in comparison with the previous method based on experimentally measured PSF and two other state-of-the-art approaches.
Subject(s)
Image Processing, Computer-Assisted , Blood Flow Velocity , Phantoms, Imaging , Principal Component Analysis , UltrasonographyABSTRACT
BACKGROUND: Attitudes and beliefs could be associated with the low number of vaccinations in low- to middle-income countries such as Vietnam. This study aims to describe ways to develop and assess the attitudes towards Hepatitis B vaccination. METHODS: A mixed-method study was carried out between April 2015 and July 2017. Qualitative data were gathered via semi-structured interviews and focus group discussions. The data were then analyzed thematically into four domains of the Health Belief Model (HBM) in order to design the structured questionnaire. The quantitative strand was followed by the evaluation of the reliability and the construct validity, for which data were obtained after interviewing 768 parents whose children aged from 12 to 24 months, who were receiving the vaccines as part of the Expanded Programme on Immunization (EPI) schedules at the Commune Health Centers. RESULTS: The findings showed the content validity index value of 13 items ranged from 0.86 to 1.00. The factor analyses showed that 11 items remained in the final questionnaire after deleting 2 problematic items due to no relation to the total scales and revealed four factors (perceived susceptibility, perceived severity, perceived benefits, perceived barriers) that jointly accounted for 62.1% of the observed variances. All four factors have good internal consistency with a total Cronbach's alpha of 0.735. A confirmatory factor analysis demonstrated the proposed factor model which fits well in four domains of HBM. CONCLUSION: Attitude scales for Hepatitis B vaccination based on HBM have been developed. This has confirmed to be a valid and reliable instrument that might be useful in assessing parents' attitudes regarding Hepatitis B vaccination and may be used to promote interventions within the increasing vaccination coverage for Vietnamese children.