85 research outputs found
The magnitude and dynamics of interocular suppression affected by monocular boundary contour and conflicting local features
AbstractA monocular boundary contour (MBC) rivalry stimulus has two half-images, a homogeneous grating and the same homogeneous grating with an additional disc region. The outline/frame of the MBC disc is created by relative phase-shift, or orientation-difference. We found the increment contrast threshold and reaction time to detect a monocular Gabor probe elevated on the homogeneous half-image pedestal. The interocular suppression begins as early as 80ms upon stimulus onset. Moreover, the suppression magnitude is larger when the MBC disc is defined by orientation-difference rather than phase-shift, revealing the suppression caused by competing local features in addition to MBC
Perceived sources of stress among Malaysian dental students
Objectives: The study objectives were to identify the stress levels and to explore the impact of students’ year of study and gender on the perceived sources of stress among Malaysian dental students.
Methods: This was a cross-sectional study involving dental students from year one to year five from private and public universities in Malaysia. The study was formally approved by the Research and Ethics Committee, International Medical University Malaysia. Dental Environment Stress (DES) questionnaire was used for data collection and the gathered data were analyzed using SPSS® version 18. The Kruskal-Wallis and the Mann-Whitney U tests were used to compare stress items across various academic years and universities.
Results: A total of five hundred and twenty nine (529) students participated in this study. Fear of failing the course at the end of year exams (mean stress level=5.57); concerns regarding completion of clinical work (mean=5.30); and examination results and grades (mean=5.27) were found as top stressors among dental students. Female students had higher stress scores than males with respect to personal issues, academic performance, educational environment and learning of clinical skills. Students from public universities had higher stress scores than their counterparts from private universities.
Conclusion: The Malaysian dental students reported higher levels of stress. Present study identified stressors affecting dental students’ academic life, and highlights the importance of stress management programs and other measures to minimize the impact of stress on both academic and personal lives of the students
Intrarenal Single-Cell Sequencing of Hepatitis B Virus Associated Membranous Nephropathy
To date, the pathogenesis of hepatitis B virus (HBV)-associated membranous nephropathy (MN) remains elusive. This study aimed to decipher the etiopathogenesis of HBV-associated MN by performing single-cell RNA sequencing (scRNA-seq) of kidney biopsy specimens from a patient with HBV-associated MN and two healthy individuals. We generated 4,114 intrarenal single-cell transcriptomes from the HBV-associated MN patient by scRNA-seq. Compared to healthy individuals, podocytes in the HBV-associated MN patient showed an increased expression of extracellular matrix formation-related genes, including HSPA5, CTGF, and EDIL3. Kidney endothelial cells (ECs) in the HBV-associated MN were enriched in inflammatory pathways, including NF-kappa B signaling, IL-17 signaling, TNF signaling and NOD-like receptor signaling. Gene ontology (GO) functional enrichment analysis and Gene Set Variation Analysis (GSVA) further revealed that differentially expressed genes (DEGs) of ECs from the HBV-associated MN patients were enriched in apoptotic signaling pathway, response to cytokine and leukocyte cell-cell adhesion. The up-regulated DEGs in glomerular ECs of HBV-associated MN patients were involved in biological processes such as viral gene expression, and protein targeting to endoplasmic reticulum. We further verified that the overexpressed genes in ECs from HBV-associated MN were mainly enriched in regulation of protein targeting to endoplasmic reticulum, exocytosis, viral gene expression, IL-6 and IL-1 secretion when compared with anti-phospholipase A2 receptor (PLA2R)-positive idiopathic membranous nephropathy (IMN). The receptor-ligand crosstalk analysis revealed potential interactions between endothelial cells and other cells in HBV-associated-MN. These results offer new insight into the pathogenesis of HBV-associated MN and may identify new therapeutic targets for HBV-associated MN
The Side Population in Human Lung Cancer Cell Line NCI-H460 Is Enriched in Stem-Like Cancer Cells
Lung cancer is among the most lethal malignancies with a high metastasis and recurrence rate. Recent studies indicate that tumors contain a subset of stem-like cancer cells that possess certain stem cell properties. Herein, we used Hoechst 33342 dye efflux assay and flow cytometry to isolate and characterize the side population (SP) cells from human lung cancer cell line NCI-H460 (H460). We show that the H460 SP cells harbor stem-like cells as they can readily form anchorage-independent floating spheres, possess great proliferative potential, and exhibit enhanced tumorigenicity. Importantly, the H460 SP cells were able to self-renew both in vitro and in vivo. Finally, we show that the H460 SP cells preferentially express ABCG2 as well as SMO, a critical mediator of the Hedgehog (HH) signaling, which seems to play an important role in H460 lung cancer cells as its blockage using Cyclopamine greatly inhibits cell-cycle progression. Collectively, our results lend further support to the existence of lung cancer stem cells and also implicate HH signaling in regulating large-cell lung cancer (stem) cells
IL-1β, IL-6, and RANTES as Biomarkers of Chikungunya Severity
Little is known about the immunopathogenesis of Chikungunya virus. Circulating levels of immune mediators and growth factors were analyzed from patients infected during the first Singaporean Chikungunya fever outbreak in early 2008 to establish biomarkers associated with infection and/or disease severity.Adult patients with laboratory-confirmed Chikungunya fever infection, who were referred to the Communicable Disease Centre/Tan Tock Seng Hospital during the period from January to February 2008, were included in this retrospective study. Plasma fractions were analyzed using a multiplex-microbead immunoassay. Among the patients, the most common clinical features were fever (100%), arthralgia (90%), rash (50%) and conjunctivitis (40%). Profiles of 30 cytokines, chemokines, and growth factors were able to discriminate the clinical forms of Chikungunya from healthy controls, with patients classified as non-severe and severe disease. Levels of 8 plasma cytokines and 4 growth factors were significantly elevated. Statistical analysis showed that an increase in IL-1beta, IL-6 and a decrease in RANTES were associated with disease severity.This is the first comprehensive report on the production of cytokines, chemokines, and growth factors during acute Chikungunya virus infection. Using these biomarkers, we were able to distinguish between mild disease and more severe forms of Chikungunya fever, thus enabling the identification of patients with poor prognosis and monitoring of the disease
Global patient outcomes after elective surgery: prospective cohort study in 27 low-, middle- and high-income countries.
BACKGROUND: As global initiatives increase patient access to surgical treatments, there remains a need to understand the adverse effects of surgery and define appropriate levels of perioperative care. METHODS: We designed a prospective international 7-day cohort study of outcomes following elective adult inpatient surgery in 27 countries. The primary outcome was in-hospital complications. Secondary outcomes were death following a complication (failure to rescue) and death in hospital. Process measures were admission to critical care immediately after surgery or to treat a complication and duration of hospital stay. A single definition of critical care was used for all countries. RESULTS: A total of 474 hospitals in 19 high-, 7 middle- and 1 low-income country were included in the primary analysis. Data included 44 814 patients with a median hospital stay of 4 (range 2-7) days. A total of 7508 patients (16.8%) developed one or more postoperative complication and 207 died (0.5%). The overall mortality among patients who developed complications was 2.8%. Mortality following complications ranged from 2.4% for pulmonary embolism to 43.9% for cardiac arrest. A total of 4360 (9.7%) patients were admitted to a critical care unit as routine immediately after surgery, of whom 2198 (50.4%) developed a complication, with 105 (2.4%) deaths. A total of 1233 patients (16.4%) were admitted to a critical care unit to treat complications, with 119 (9.7%) deaths. Despite lower baseline risk, outcomes were similar in low- and middle-income compared with high-income countries. CONCLUSIONS: Poor patient outcomes are common after inpatient surgery. Global initiatives to increase access to surgical treatments should also address the need for safe perioperative care. STUDY REGISTRATION: ISRCTN5181700
Ценностные ориентации, как основа для формирования профессиональных компетенций учащихся специальности «Медико-профилактическое дело»
ОБРАЗОВАНИЕ МЕДИЦИНСКОЕМЕДИЦИНСКИЕ УЧЕБНЫЕ ЗАВЕДЕНИЯПРОФЕССИОНАЛЬНЫЕ КОМПЕТЕНЦИИСТУДЕНТЫ МЕДИЦИНСКИХ УЧЕБНЫХ ЗАВЕДЕНИЙКОМПЕТЕНТНОСТНЫЙ ПОДХОДЦЕННОСТНЫЕ ОРИЕНТАЦИИМЕДИКО-ПРОФИЛАКТИЧЕСКОЕ ДЕЛО (СПЕЦИАЛЬНОСТЬ
Coexistence of binocular integration and suppression determined by surface border information
The visual system relies on both the integration and interocular inhibitory processes to achieve single vision from different images in the two eyes. It is generally assumed that the integration process first searches for matching local features between the two eyes. If the matching fails, an interocular inhibitory process is triggered to suppress the image representation of one eye, leading to visual perception that is essentially contributed by the other eye. Here, using a stimulus comprising of binocularly corresponding features (vertical gratings) but incompatible surface border information, we found evidence to the contrary. In one half-image, a circular patch of vertical grating was phase-shifted relative to the surrounding vertical grating to create a circular, monocular boundary contour (MBC), while the other half-image had a similar vertical grating. The two half-images had a binocular disparity at the circular grating patch area, leading to the percept of a disc in depth. Concurrent with the stereo percept, threshold for detecting a Gabor probe on the half-image without the MBC was higher than that on the corresponding area with the grating disc, indicating binocular suppression. These findings reveal that when we perceive depth, which requires the integration process to obtain binocular disparity from the two eyes, one eye's image could simultaneously be suppressed from visual awareness by the interocular inhibitory process. Our study also presents a provocative example of where the brain selectively binds some, but not all, features of the images from the two eyes for visual perception
Adaptive antenna adjustment for 3D urban wireless mesh networks
10.1109/SAHCN.2013.66449772013 IEEE International Conference on Sensing, Communications and Networking, SECON 2013185-19
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