scholarly journals Delay-dependent cholinergic modulation of visual short-term memory in rhesus macaques

2020 ◽  
Author(s):  
Balázs Knakker ◽  
Vilmos Oláh ◽  
Attila Trunk ◽  
Balázs Lendvai ◽  
György Lévay ◽  
...  
Keyword(s):  
Acetylcholine Receptors ◽  
Short Term Memory ◽  
Current Knowledge ◽  
Rhesus Macaques ◽  
Acetylcholinesterase Inhibitor ◽  
Muscarinic Acetylcholine Receptors ◽  
Time Range ◽  
Wide Range ◽  
Delay Dependent

AbstractCholinergic neuromodulation is known to play a key role in visual working memory (VWM) – keeping relevant stimulus representations available for cognitive processes for short time periods up to a few minutes. Despite the growing body of evidence on how the neural and cognitive mechanisms of VWM dynamically change over retention time, there is mixed evidence available on cholinergic effects as a function of VWM delay period in non-human primates. Using the delayed matching to sample VWM task in rhesus macaques (N=6), we aimed to characterize VWM maintenance in terms of performance changes as a function of delay duration (across a wide range of delays from 1 to 76 s). Then, we studied how cholinergic neuromodulation influences VWM maintenance using the muscarinic receptor antagonist scopolamine administered alone as transient amnestic treatment, and in combination with two doses of the acetylcholinesterase inhibitor donepezil, a widely used Alzheimer’s medication probing for the reversal of scopolamine-induced impairments. Results indicate that scopolamine-induced impairments of VWM maintenance are delay-dependent and specifically affect the 15-33 s time range, suggesting that scopolamine worsens the normal decay of VWM with the passage of time. Donepezil partially rescued the observed scopolamine-induced impairments of VWM performance. These results provide strong behavioral evidence for the role of increased cholinergic tone and muscarinic neuromodulation in the maintenance of VWM beyond a few seconds, in line with our current knowledge on the role of muscarinic acetylcholine receptors in sustained neural activity during VWM delay periods.

scholarly journals The Role of Spinal Muscarinic Acetylcholine Receptors in Clonidine-Induced Anti-nociceptive Effects in Rats

2003 ◽  
Vol 26 (8) ◽  
pp. 1178-1180 ◽  
Author(s):  
Kenji Honda ◽  
Namiko Murao ◽  
Takae Ibuki ◽  
Hiro-o Kamiya ◽  
Yukio Takano
Keyword(s):  
Acetylcholine Receptors ◽  
Muscarinic Acetylcholine Receptors ◽  
Muscarinic Acetylcholine

scholarly journals Neutrophil Extracellular Traps in Periodontitis

Cells ◽  
2020 ◽  
Vol 9 (6) ◽  
pp. 1494 ◽  
Author(s):  
Antonio Magán-Fernández ◽  
Sarmad Muayad Rasheed Al-Bakri ◽  
Francisco O’Valle ◽  
Cristina Benavides-Reyes ◽  
Francisco Abadía-Molina ◽  
...  
Keyword(s):  
Current Knowledge ◽  
Decisive Role ◽  
Neutrophil Extracellular Traps ◽  
Gingival Tissue ◽  
Multifactorial Disease ◽  
Extracellular Traps ◽  
Wide Range ◽  
Neutrophil Response ◽  
Inflammatory Component

Neutrophils are key cells of the immune system and have a decisive role in fighting foreign pathogens in infectious diseases. Neutrophil extracellular traps (NETs) consist of a mesh of DNA enclosing antimicrobial peptides and histones that are released into extracellular space following neutrophil response to a wide range of stimuli, such as pathogens, host-derived mediators and drugs. Neutrophils can remain functional after NET formation and are important for periodontal homeostasis. Periodontitis is an inflammatory multifactorial disease caused by a dysbiosis state between the gingival microbiome and the immune response of the host. The pathogenesis of periodontitis includes an immune-inflammatory component in which impaired NET formation and/or elimination can be involved, contributing to an exacerbated inflammatory reaction and to the destruction of gingival tissue. In this review, we summarize the current knowledge about the role of NETs in the pathogenesis of periodontitis.

scholarly journals Tissue-Nonspecific Alkaline Phosphatase—A Gatekeeper of Physiological Conditions in Health and a Modulator of Biological Environments in Disease

Biomolecules ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1648
Author(s):  
Daniel Liedtke ◽  
Christine Hofmann ◽  
Franz Jakob ◽  
Eva Klopocki ◽  
Stephanie Graser
Keyword(s):  
Alkaline Phosphatase ◽  
Clinical Symptoms ◽  
Current Knowledge ◽  
Systemic Disease ◽  
Loss Of Function ◽  
Inorganic Pyrophosphate ◽  
Wide Range ◽  
Mineralization Processes ◽  
Tissue Nonspecific Alkaline Phosphatase

Tissue-nonspecific alkaline phosphatase (TNAP) is a ubiquitously expressed enzyme that is best known for its role during mineralization processes in bones and skeleton. The enzyme metabolizes phosphate compounds like inorganic pyrophosphate and pyridoxal-5′-phosphate to provide, among others, inorganic phosphate for the mineralization and transportable vitamin B6 molecules. Patients with inherited loss of function mutations in the ALPL gene and consequently altered TNAP activity are suffering from the rare metabolic disease hypophosphatasia (HPP). This systemic disease is mainly characterized by impaired bone and dental mineralization but may also be accompanied by neurological symptoms, like anxiety disorders, seizures, and depression. HPP characteristically affects all ages and shows a wide range of clinical symptoms and disease severity, which results in the classification into different clinical subtypes. This review describes the molecular function of TNAP during the mineralization of bones and teeth, further discusses the current knowledge on the enzyme’s role in the nervous system and in sensory perception. An additional focus is set on the molecular role of TNAP in health and on functional observations reported in common laboratory vertebrate disease models, like rodents and zebrafish.

scholarly journals Evolving Role of Microparticles in the Pathophysiology of Endothelial Dysfunction

2013 ◽  
Vol 59 (8) ◽  
pp. 1166-1174 ◽  
Author(s):  
Fina Lovren ◽  
Subodh Verma
Keyword(s):  
Endothelial Cells ◽  
Cardiovascular Diseases ◽  
Endothelial Dysfunction ◽  
Vascular Endothelial Cells ◽  
Current Knowledge ◽  
Early Event ◽  
Prognostic Information ◽  
Vascular Events ◽  
Wide Range

BACKGROUND Endothelial dysfunction is an early event in the development and progression of a wide range of cardiovascular diseases. Various human studies have identified that measures of endothelial dysfunction may offer prognostic information with respect to vascular events. Microparticles (MPs) are a heterogeneous population of small membrane fragments shed from various cell types. The endothelium is one of the primary targets of circulating MPs, and MPs isolated from blood have been considered biomarkers of vascular injury and inflammation. CONTENT This review summarizes current knowledge of the potential functional role of circulating MPs in promoting endothelial dysfunction. Cells exposed to different stimuli such as shear stress, physiological agonists, proapoptotic stimulation, or damage release MPs, which contribute to endothelial dysfunction and the development of cardiovascular diseases. Numerous studies indicate that MPs may trigger endothelial dysfunction by disrupting production of nitric oxide release from vascular endothelial cells and subsequently modifying vascular tone. Circulating MPs affect both proinflammatory and proatherosclerotic processes in endothelial cells. In addition, MPs can promote coagulation and inflammation or alter angiogenesis and apoptosis in endothelial cells. SUMMARY MPs play an important role in promoting endothelial dysfunction and may prove to be true biomarkers of disease state and progression.

scholarly journals Regulation of ST6GAL1 sialyltransferase expression in cancer cells

Glycobiology ◽  
2020 ◽  
Author(s):  
Kaitlyn A Dorsett ◽  
Michael P Marciel ◽  
Jihye Hwang ◽  
Katherine E Ankenbauer ◽  
Nikita Bhalerao ◽  
...  
Keyword(s):  
Cancer Cells ◽  
Translational Regulation ◽  
Molecular Mechanisms ◽  
Current Knowledge ◽  
Sialic Acids ◽  
Invasion Resistance ◽  
Cell Behaviors ◽  
Molecular Events ◽  
Wide Range

Abstract The ST6GAL1 sialyltransferase, which adds α2–6 linked sialic acids to N-glycosylated proteins, is overexpressed in a wide range of human malignancies. Recent studies have established the importance of ST6GAL1 in promoting tumor cell behaviors such as invasion, resistance to cell stress, and chemoresistance. Furthermore, ST6GAL1 activity has been implicated in imparting cancer stem cell characteristics. However, despite the burgeoning interest in the role of ST6GAL1 in the phenotypic features of tumor cells, insufficient attention has been paid to the molecular mechanisms responsible for ST6GAL1 upregulation during neoplastic transformation. Evidence suggests that these mechanisms are multifactorial, encompassing genetic, epigenetic, transcriptional, and post-translational regulation. The purpose of this review is to summarize current knowledge regarding the molecular events that drive enriched ST6GAL1 expression in cancer cells.

scholarly journals Role of active patient involvement in undergraduate medical education: a systematic review

BMJ Open ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. e037217
Author(s):  
Stijntje Willemijn Dijk ◽  
Edwin Johan Duijzer ◽  
Matthias Wienold
Keyword(s):  
Systematic Review ◽  
Medical Education ◽  
Undergraduate Medical Education ◽  
Patient Involvement ◽  
Current Knowledge ◽  
Daily Practice ◽  
Pubmed Database ◽  
Wide Range ◽  
Active Patient

ObjectivesTo identify the scope of active patient involvement in medical education, addressing the current knowledge gaps relating to rationale and motivation for involvement, recruitment and preparation, roles, learning outcomes and key procedural contributors.MethodsThe authors performed a systematic search of the PubMed database of publications between 2003 and 2018. Original studies in which patients take on active roles in the development, delivery or evaluation of undergraduate medical education and written in English were eligible for inclusion. Included studies’ references were searched for additional articles. Quality of papers was assessed using the Mixed Methods Appraisal Tool.Results49 articles were included in the review. Drivers for patient involvement included policy requirements and patients’ own motivations to contribute to society and learning. Patients were engaged in a variety of educational settings in and outside of the hospital. The vast majority of studies describe patients taking on the role of a patient teacher and formative assessor. More recent studies suggest that patients are increasingly involved in course and curriculum development, student selection and summative assessment. The new body of empirical evidence shows the wide range of learning objectives was pursued through patient participation, including competencies as professional, communicator, collaborator, leader and health advocate, but not scholar. Measures to support sustainable patient involvement included longitudinal institutional incorporation, patient recruitment and/or training, resource support and clear commitment by faculty. The importance and advantages of patient involvement were highlighted by students, faculty and patients themselves; however, organisations must continue to consider, monitor and take steps to mitigate any potential harms to patients and students.DiscussionThis systematic review provides new knowledge and practical insights to physicians and faculty on how to incorporate active patient involvement in their institutions and daily practice, and provides suggested action points to patient organisations wishing to engage in medical education.

Stomatal conductance scales with petiole xylem traits in Populus genotypes

2016 ◽  
Vol 43 (6) ◽  
pp. 553 ◽  
Author(s):  
Caroline A. Brocious ◽  
Uwe G. Hacke
Keyword(s):  
Stomatal Conductance ◽  
Current Knowledge ◽  
Hybrid Poplar ◽  
Leaf Size ◽  
Exchange Capacity ◽  
Vein Density ◽  
Wide Range ◽  
Major Vein ◽  
Size And Morphology

Progress has been made in linking water transport in leaves with anatomical traits. However, most of our current knowledge about these links is based on studies that sampled phylogenetically distant species and covered a wide range of leaf size and morphology. Here we studied covariation of leaf anatomical traits and hydraulic capacity in five closely related hybrid poplar genotypes. Variation in stomatal conductance and leaf hydraulic conductance was not linked to vein density or other anatomical lamina properties. A strong correlation was found between stomatal conductance and the transport capacity of the petiole, estimated from the diameter and number of xylem vessels. An inverse relationship existed between leaf size and major vein density. The role of bundle sheath extensions is discussed. Our data suggests that petiole xylem is an important predictor of gas exchange capacity in poplar leaves.

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