12 research outputs found
Eosinophil adhesion under flow conditions activates mechanosensitive signaling pathways in human endothelial cells
Leukocyte transmigration can be affected by shear stress; however, the mechanisms by which shear stress modulates transmigration are unknown. We found that adhesion of eosinophils or an eosinophilic cell line to intereukin 4–stimulated endothelial cells led to a shear-dependent increase in endothelial cell intracellular calcium and increased phosphorylation of extracellular signal-regulated kinase (ERK) 2, but not c-Jun NH2-terminal kinase or p38 mitogen-activated protein kinase. Latex beads coated with antibodies were used to characterize the role of specific endothelial cell surface molecules in initiating signaling under shear conditions. We found that ligation of either vascular cell adhesion molecule–1 or E-selectin, but not major histocompatibility complex class I, induced a shear-dependent increase in ERK2 phosphorylation in cytokine-stimulated endothelial cells. Disassembly of the actin cytoskeleton with latrunculin A prevented ERK2 phosphorylation after adhesion under flow conditions, supporting a role for the cytoskeleton in mechanosensing. Rapid phosphorylation of focal adhesion kinase and paxillin occurred under identical conditions, suggesting that focal adhesions were also involved in mechanotransduction. Finally, we found that Rho-associated protein kinase and calpain were both critical in the subsequent transendothelial migration of eosinophils under flow conditions. These data suggest that ligation of leukocyte adhesion molecules under flow conditions leads to mechanotransduction in endothelial cells, which can regulate subsequent leukocyte trafficking
Medical Students’ Satisfaction with a Web-based Training Module of Clinical Reasoning
Background: There is a paucity of literature regarding the medical students’ perspectives on
web-based training of clinical reasoning.
Objectives: This study aimed to describe the implementation of a web-based training course
of clinical reasoning for medical students and to evaluate their satisfaction with the program.
Methods: This cross-sectional study was conducted at the Tehran University of Medical
Sciences in 2018. Fifty internal medicine interns were consecutively enrolled. The study
consisted of two phases. The first phase focused on the development of a web-based training
module of clinical reasoning. The second focused on evaluating the trainee’s satisfaction with
the virtual course. The educational content of the program was prepared by an expert panel
and incorporated in a web-based educational tool designed for virtual training purposes. The
students’ satisfaction with the virtual course was assessed using a questionnaire. Each item of
the questionnaire was scored from 0 (0) to 1.5 (100). The content validity of the questionnaire
determined by an expert panel, and its reliability was measured.
Results: The mean score of each item of the questionnaire ranged from 77.3 to 85.3 which
showed that the participants agreed with the items of the questionnaire. Also, Cronbach’s
alpha coefficient was excellent in nine items of the questionnaire, good in four items, and
acceptable in three items. The intraclass correlation coefficient was also estimated as 0.98.
Conclusions: The participants were satisfied with the web-based training tool for clinical
reasoning, used in the present study. The developed questionnaire also showed good validity
and reliability for the assessment of trainees’ satisfaction with the web-based training module
of clinical reasoning.
Keywords: Logic, Distance Education, Assessment, Medical Studen
Proteinase-activated receptor 2 modulates neuroinflammation in experimental autoimmune encephalomyelitis and multiple sclerosis
The proteinase-activated receptors (PARs) are widely recognized for their modulatory properties of inflammation and neurodegeneration. We investigated the role of PAR2 in the pathogenesis of multiple sclerosis (MS) in humans and experimental autoimmune encephalomyelitis (EAE) in mice. PAR2 expression was increased on astrocytes and infiltrating macrophages in human MS and murine EAE central nervous system (CNS) white matter (P < 0.05). Macrophages and astrocytes from PAR2 wild-type (WT) and knockout (KO) mice exhibited differential immune gene expression with PAR2 KO macrophages showing significantly higher interleukin 10 production after lipopolysaccharide stimulation (P < 0.001). PAR2 activation in macrophages resulted in the release of soluble oligodendrocyte cytotoxins (P < 0.01). Myelin oligodendrocyte glycoprotein–induced EAE caused more severe inflammatory gene expression in the CNS of PAR2 WT animals (P < 0.05), together with enhanced T cell proliferation and interferon γ production (P < 0.05), compared with KO littermates. Indeed, PAR2 WT animals showed markedly greater microglial activation and T lymphocyte infiltration accompanied by worsened demyelination and axonal injury in the CNS compared with their PAR2 KO littermates. Enhanced neuropathological changes were associated with a more severe progressive relapsing disease phenotype (P < 0.001) in WT animals. These findings reveal previously unreported pathogenic interactions between CNS PAR2 expression and neuroinflammation with ensuing demyelination and axonal injury
Diagnostic Value of the Urine Mucus Test in Childhood Masturbation among Children below 12 Years of Age: AÂ Cross-Sectional Study from Iran
Background: Childhood masturbation (CM) is considered a variant of normal sexual behavior; however, it is commonly misdiagnosed as epilepsy and movement disorders. As the first study from Iran, we analyzed a large population of infants and children with CM in a case-control study and evaluated the value of mucus in urine analysis as an alternative diagnostic tool for CM.
Methods: A total of 623 children referred to the Pediatric Neurology Clinic of Imam Khomeini Hospital for an evaluation of seizure or movement disorders were studied between 2008 and 2011. Totally, 359 children were found to have masturbatory behaviors (Group A) and the rest (264) were assigned to Group B. CM was diagnosed by direct observation. Collected data comprised demographic characteristics, clinical and neurodevelopmental examinations, laboratory findings (particularly urine analysis), and electrocardiography.
Results: The age of the children with CM was below 12 years old, and the girl-to-boy ratio was 7:1. Mucus in urine was positive in 357 (99.44%) children in Group A and 22 (8.3%) in Group B (P<0.001). A significant correlation was found between the presence of mucus in urine and masturbatory behaviors (P<0.001).
Conclusion: Our findings suggest that the presence of mucus in urine can be used as an alternative laboratory test in children with CM below 12 years old and even in infants (≤24 months old). Further studies are needed to confirm the results