Art-based assignment in head and neck anatomical course, a dynamic experience

In recent years, alternative uses of art within medical education have been explored and extended. We report here a method of art-based assignments in anatomy and histology, which we have incorporated into the head and neck course as a means of enlivening didactic lectures. One hundred and two first-year medical students at the Alborz University of Medical Sciences participated in a 15-week educational intervention, in which an art-based assignment method was employed. The learning module focuses on the human anatomy and histology of head and neck. In each session, after the teacher's lecture and practical work, students were given an assignment based on the topics of that session and based on the drawing. The learning outcome was evaluated twice, 1 week and 4 weeks after the course. Student's feedbacks were collected via an anonymous questionnaire at the end of the module. The data were analyzed by using the SPSS 20 software by paired and independent t-tests and the normality of data was evaluated by the Kolmogorov–Smirnov test. Most of students (90%) had rated the new format as very informative. Exam scores were significantly higher at 4 weeks tests (P ≤ 0.05) and data showed significant difference in long-term retention of knowledge. The use of this module by medical students during their head and neck course improves their confidence through drawing. Teacher's feedback provides a step-wise approach that simplifies the learning of anatomy and histology. The strategy has appeal for visual, auditory, read/write, and kinesthetic learners

Effects of chronic hypoxia on the expression of seladin-1/Tuj1 and the number of dark neurons of hippocampus

Background: There are evidences showing the relation between chronic hypoxia and Alzheimer&#39;s disease (AD) as a metabolic neurodegenerative disease. This study was designed to evaluate the effects of chronic hypoxia on factors which characterized in AD to introduce a new model of AD-dementia. Methods and materials: Twenty-four male rats were randomly divided in three groups: Control group (Co), Sham group (Sh), Hypoxia induction group (Hx, exposed to hypoxic chamber [oxygen 8% and nitrogen 92%] for 30 days, 4 h/day). Spatial learning and memory were analyzed using the Morris water maze task. At day 30 after hypoxia period, animals were sacrificed and serum was gathered for pro-inflammatory cytokines (interleukin-1 beta and tumor necrosis factor) measurements and brains were used for molecular and histopathological investigations. Results: According to behavioral studies, a significant impairment was seen in Hx group (P &lt; 0.05). TNF-alpha and IL-1 beta showed a significant enhanced in Hx group comparing with Co group and Sh group (P &lt; 0.05). As well, the gene expression of seladin-1, Tuj1 and the number of seladin-1 +, Tuj1 +neurons significantly decreased and also the mean number of dark neurons significantly increased in CA1 and CA3 regions of hippocampus. Conclusions: In this study, a new model of AD was developed which showed the underlying mechanisms of AD and its relations with chronic hypoxia. Hypoxia for 30 days decreased seladin-1, Tuj1 expression, increased the number of dark neurons, and also induced memory impairment. These results indicated that chronic hypoxia mediated the dementia underlying AD and AD-related pathogenesis in rat.</p

Effect of Magnetic Tacrine-Loaded Chitosan Nanoparticles on Spatial Learning, Memory, Amyloid Precursor Protein and Seladin-1 Expression in the Hippocampus Of Streptozotocin-Exposed Rats

Alzheimer's disease (AD) is a progressive neurodegenerative disease characterized by memory and cognitive dysfunction due to neuronal cell loss in higher brain centers. Senile plaques containing amyloid β (Aβ) are associated with this disease as well as a reduction in cholinergic neuron numbers. Tacrine is a reversible cholinesterase inhibitor in clinical use to treat moderate forms of AD. Chitosan nanoparticles represent an effective systemic delivery system for drugs. The application of tacrine-loaded chitosan nanoparticles has been shown to selectively increase tacrine concentrations in the brain tissue. In this study, we compared magnetic and non-magnetic tacrine-loaded chitosan nanoparticles for their bioactivity and neuroprotective potency in streptozotocin (stz)-induced neurodegeneration, an accepted animal model for AD. Male rats received a single injection of stz via an implanted cannula into the lateral brain ventricle. Tacrine (tac)-loaded chitosan nanoparticles were delivered into the tail vein. Spatial learning and memory were analyzed using the Morris water maze task. Amyloid precursor protein gene (APP) and seladin-1 gene expression were studied in the hippocampus by real time-PCR. Tac-loaded non-magnetic and tac-loaded magnetic chitosan nanoparticles improved spatial learning and memory after stz treatment with magnetic nanoparticles being most effective. Similarly, tac-loaded chitosan nanoparticles increased seladin-1 and reduced APP gene expression. Again, magnetic nanoparticles were more effective. These data reveal that tac-loaded non magnetic and tac-loaded magnetic chitosan nanoparticles to a higher extent improve brain deficits related to stz application. We conclude that the magnetic target drug delivery system is a promising therapeutic strategy to protect AD-related degenerating in the CNS.

Contribution of Extracellular Vesicles and Molecular Chaperones in Age-Related Neurodegenerative Disorders of the CNS

Many neurodegenerative disorders are characterized by the abnormal aggregation of misfolded proteins that form amyloid deposits which possess prion-like behavior such as self-replication, intercellular transmission, and consequent induction of native forms of the same protein in surrounding cells. The distribution of the accumulated proteins and their correlated toxicity seem to be involved in the progression of nervous system degeneration. Molecular chaperones are known to maintain proteostasis, contribute to protein refolding to protect their function, and eliminate fatally misfolded proteins, prohibiting harmful effects. However, chaperone network efficiency declines during aging, prompting the onset and the development of neurological disorders. Extracellular vesicles (EVs) are tiny membranous structures produced by a wide range of cells under physiological and pathological conditions, suggesting their significant role in fundamental processes particularly in cellular communication. They modulate the behavior of nearby and distant cells through their biological cargo. In the pathological context, EVs transport disease-causing entities, including prions, α-syn, and tau, helping to spread damage to non-affected areas and accelerating the progression of neurodegeneration. However, EVs are considered effective for delivering therapeutic factors to the nervous system, since they are capable of crossing the blood–brain barrier (BBB) and are involved in the transportation of a variety of cellular entities. Here, we review the neurodegeneration process caused mainly by the inefficiency of chaperone systems as well as EV performance in neuropathies, their potential as diagnostic biomarkers and a promising EV-based therapeutic approach