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Melatonin enhances neural stem cell differentiation and engraftment by increasing mitochondrial function
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Miguel Mendivil‐Perez Viviana Soto‐Mercado Ana Guerra‐Librero Beatriz I. Fernandez‐Gil Javier Florido Ying‐Qiang Shen Miguel A. Tejada Vivian Capilla‐Gonzalez Iryna Rusanova José M. Garcia‐Verdugo Darío Acuña‐Castroviejo Luis Carlos López Carlos Velez‐Pardo Marlene Jimenez‐Del‐Rio José M. Ferrer Germaine Escames 《Journal of pineal research》2017,63(2)
Neural stem cells (NSCs) are regarded as a promising therapeutic approach to protecting and restoring damaged neurons in neurodegenerative diseases (NDs) such as Parkinson's disease and Alzheimer's disease (PD and AD, respectively). However, new research suggests that NSC differentiation is required to make this strategy effective. Several studies have demonstrated that melatonin increases mature neuronal markers, which reflects NSC differentiation into neurons. Nevertheless, the possible involvement of mitochondria in the effects of melatonin during NSC differentiation has not yet been fully established. We therefore tested the impact of melatonin on NSC proliferation and differentiation in an attempt to determine whether these actions depend on modulating mitochondrial activity. We measured proliferation and differentiation markers, mitochondrial structural and functional parameters as well as oxidative stress indicators and also evaluated cell transplant engraftment. This enabled us to show that melatonin (25 μM) induces NSC differentiation into oligodendrocytes and neurons. These effects depend on increased mitochondrial mass/DNA/complexes, mitochondrial respiration, and membrane potential as well as ATP synthesis in NSCs. It is also interesting to note that melatonin prevented oxidative stress caused by high levels of mitochondrial activity. Finally, we found that melatonin enriches NSC engraftment in the ND mouse model following transplantation. We concluded that a combined therapy involving transplantation of NSCs pretreated with pharmacological doses of melatonin could efficiently restore neuronal cell populations in PD and AD mouse models depending on mitochondrial activity promotion. 相似文献
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IgG4-related disease is defined as a multi-organ systemic disorder with pathological findings affecting a wide range of organ systems. The condition unifies a large number of clinical diagnoses previously considered as being confined to single organ systems. At present, several issues related to its pathophysiology remained controversial, including the natural history of the disease, the pathogenic role of IgG4, and its use as a biomarker. Glucocorticoids are considered the treatment of choice for remission induction of IgG4-related disease manifestations; however, concerns regarding duration of therapy and management of refractory disease remained to be elucidated. 相似文献
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Jasmine Martinez Christine Liu Nyah Rodman Jennifer S. Fernandez Claudia Barberis Rodrigo Sieira Federico Perez Robert A. Bonomo Maria Soledad Ramirez 《Diagnostic microbiology and infectious disease》2019,93(3):183-187
Transformation is one of the mechanisms of acquisition of foreign genetic material leading to the emergence of multidrug resistant (MDR) bacteria. Recently, human serum albumin (HSA) was shown to specifically increase transformation frequency in the nosocomial pathogen Acinetobacter baumannii. To further assess the relevance of HSA as a possible modulator of A. baumannii transformation in host-pathogen interactions, in this work we examined the effect of different human fluids. We observed a significant increase in transformation frequencies in the presence of pleural fluid, whole blood cells and liquid ascites, and to a lesser extent with urine. The observed effects correlate with both HSA and bacterial content found in the assayed patient fluids. Taken together, these results are in agreement with our previous findings that highlight HSA as a possible host signal with the ability to trigger natural transformation in A. baumannii. 相似文献
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Tracy Anton Mark S. Sklansky Mishella Perez Dolores H. Pretorius 《Journal of ultrasound in medicine》2019,38(12):3335-3347
In 2018, the American Institute of Ultrasound in Medicine revised its obstetric Practice Parameter for the second‐trimester fetal anatomic survey. The 2018 Practice Parameter recommends incorporation of the 3‐vessel view and 3‐vessel and trachea view “if technically feasible.” Sonographers and other medical providers may require additional training and education to develop greater proficiency in obtaining and interpreting these views. This pictorial essay, including ultrasound images alongside their respective schematic diagrams, provides an up‐to‐date, practical, and clinically oriented review of the 3‐vessel view and 3‐vessel and trachea view and their most common presentations in the context of congenital heart disease. 相似文献
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Jorge Rey-Martinez Angel Batuecas-Caletrio Eusebi Matiño Nicolás Perez Fernandez 《Acta oto-laryngologica》2015,135(9):886-894
Conclusion: The developed software (HITCal) may be a useful tool in the analysis and measurement of the saccadic video head impulse test (vHIT) responses and with the experience obtained during its use the authors suggest that HITCal is an excellent method for enhanced exploration of vHIT outputs. Objective: To develop a (software) method to analyze and explore the vHIT responses, mainly saccades. Methods: HITCal was written using a computational development program; the function to access a vHIT file was programmed; extended head impulse exploration and measurement tools were created and an automated saccade analysis was developed using an experimental algorithm. For pre-release HITCal laboratory tests, a database of head impulse tests (HITs) was created with the data collected retrospectively in three reference centers. This HITs database was evaluated by humans and was also computed with HITCal. Results: The authors have successfully built HITCal and it has been released as open source software; the developed software was fully operative and all the proposed characteristics were incorporated in the released version. The automated saccades algorithm implemented in HITCal has good concordance with the assessment by human observers (Cohen’s kappa coefficient = 0.7). 相似文献
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