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1.
Cell ; 139(2): 380-92, 2009 Oct 16.
Article in English | MEDLINE | ID: mdl-19818485

ABSTRACT

Synapses are asymmetric cellular adhesions that are critical for nervous system development and function, but the mechanisms that induce their formation are not well understood. We have previously identified thrombospondin as an astrocyte-secreted protein that promotes central nervous system (CNS) synaptogenesis. Here, we identify the neuronal thrombospondin receptor involved in CNS synapse formation as alpha2delta-1, the receptor for the anti-epileptic and analgesic drug gabapentin. We show that the VWF-A domain of alpha2delta-1 interacts with the epidermal growth factor-like repeats common to all thrombospondins. alpha2delta-1 overexpression increases synaptogenesis in vitro and in vivo and is required postsynaptically for thrombospondin- and astrocyte-induced synapse formation in vitro. Gabapentin antagonizes thrombospondin binding to alpha2delta-1 and powerfully inhibits excitatory synapse formation in vitro and in vivo. These findings identify alpha2delta-1 as a receptor involved in excitatory synapse formation and suggest that gabapentin may function therapeutically by blocking new synapse formation.


Subject(s)
CD36 Antigens/metabolism , Calcium Channels/metabolism , Neurogenesis , Synapses , Amines/pharmacology , Animals , Calcium Channels, L-Type , Cyclohexanecarboxylic Acids/pharmacology , Gabapentin , Mice , Neuronal Plasticity , Neurons/metabolism , Rats , Rats, Sprague-Dawley , Synapses/drug effects , gamma-Aminobutyric Acid/pharmacology
2.
Qual Inq ; 30(2): 175-181, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38344057

ABSTRACT

The rhythmic interplay of accent, tempo, and musical mood is expressed in the bodily postures, gestures, and expressions of attuned responsiveness in Salsa Dura, a genre of salsa music from the 1970s featuring improvisational dance solos. These dancers embrace the feelings and flows of soloing musicians going off and breaking free from any predictable form and structure. We inquire into how world-class salsa dancers and educators feel themselves moved by such intricate rhythms to experience soul connections. Video recordings and interviews yield insight into the call and response dynamics of this essentially tactful practice of alterity.

3.
Am J Hum Biol ; 35(11): e23942, 2023 11.
Article in English | MEDLINE | ID: mdl-37341438

ABSTRACT

OBJECTIVES: Testosterone concentrations in men decline with advancing age. However, the cause of the decline is yet to be fully elucidated. Therefore, the aims of this study were to examine the associations between chronic diseases such as obesity and type 2 diabetes mellitus (T2DM) with total testosterone (TT) and sex hormone-binding globulin (SHBG), using a large nationally-representative data set (National Health and Nutrition Examination Survey; NHANES). METHODS: NHANES is a cross-sectional survey, physical examination, and laboratory evaluation of a nationally-representative sample of a non-institutionalized United States population. Male participants aged ≥18 years during the NHANES 2013-2014 and NHANES 2015-2016 survey periods were selected for this analysis. The analysis included the following data: body mass index (BMI), oral glucose tolerance test (OGTT), homeostatic model assessment of insulin resistance (HOMA-IR), insulin, glucose, and age. RESULTS: An overweight or obese condition was significantly inversely associated with TT and SHBG, even after adjusting for other variables. Several variables associated with T2DM (OGTT, HOMA-IR, insulin, and glucose) were also inversely associated with TT; however, only the associations between OGTT and insulin with TT remained significant after adjusting for the other variables. Insulin and HOMA-IR levels were significantly inversely associated with SHBG; however, only the association between SHBG and pre-diabetic HOMA-IR levels remained significant after adjusting for the other variables. OGTT became significantly associated with SHBG after adjusting for the other variables. Age was significantly inversely associated with TT, but positively associated with SHBG, even after adjusting for other variables. CONCLUSION: The results of the present study, which is the largest to date, indicate that a marker of obesity, BMI, and some markers of T2DM are both independently and significantly inversely associated with TT and SHBG.


Subject(s)
Diabetes Mellitus, Type 2 , Insulin Resistance , Humans , Male , Adolescent , Adult , Testosterone , Diabetes Mellitus, Type 2/epidemiology , Nutrition Surveys , Cross-Sectional Studies , Insulin , Obesity/epidemiology , Biomarkers , Glucose
4.
Nutr Neurosci ; 25(8): 1704-1730, 2022 Aug.
Article in English | MEDLINE | ID: mdl-33650944

ABSTRACT

INTRODUCTION: The hypothalamic-pituitary-adrenal (HPA) axis plays a central role in the stress response. Plants, herbs, spices, and plant-based nutrients may influence HPA-axis activity. OBJECTIVE: To evaluate randomised controlled, human trials assessing the effects of single plants or phytonutrients on HPA-axis related hormones. METHODS: A systematic review of PubMed, Cochrane library, and the Cumulative Index to Nursing and Allied Health Literature was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Inclusion criteria comprised of human, randomised controlled studies with a control intervention examining the effects of a single herb, spice, plant, or extract on pre- and post-changes in blood, saliva, urine, or hair concentrations of cortisol, cortisone, corticotrophin-releasing hormone, or adrenocorticotropic hormone. Databases were searched from inception until October 2020. RESULTS: Fifty-two studies were identified examining the effects of ashwagandha, Korean ginseng, St John's Wort, cannabidiol, Rhodiola rosea, curcumin, cherry juice, asparagus, Jiaogulan, Black cohosh, Siberian ginseng, Bacopa monnieri, blueberries, green tea, Caralluma fimbriata, cashew apple juice, melon, American ginseng, Ginkgo biloba, grape juice, grapefruit juice, rosella, hops, mangosteen, holy basil, and pomegranate juice. Due to significant variability in study designs, the effect of phytonutrients on HPA-axis activity in humans was unclear. The most consistent finding was a morning, cortisol-lowering effect from ashwagandha supplementation. CONCLUSION: For most phytonutrients, the effects of supplementation on HPA-axis activity in humans is unclear. Before more definitive conclusions about the effects of phytonutrients on the HPA-axis can be made, further research is required.


Subject(s)
Hydrocortisone , Pituitary-Adrenal System , Adrenocorticotropic Hormone/pharmacology , Humans , Hydrocortisone/analysis , Hypothalamo-Hypophyseal System , Phytochemicals/pharmacology
5.
IEEE Trans Appl Supercond ; 1: 1, 2021 Jan 21.
Article in English | MEDLINE | ID: mdl-33531792

ABSTRACT

Pulses of narrow line-width optical photons can be used to calibrate and test sub-2 eV full-width at halfmaximum (FWHM) energy resolution transition-edge sensor (TES) microcalorimeters at low energies (< 1 keV), where it is very challenging to obtain X-ray calibration lines comparable to (or narrower than) the detector resolution. This scheme depends on the ability to resolve the number of 3 eV photons in each pulse, which we have recently demonstrated up to photon numbers of about 300. At LTD-18 we showed preliminary results obtained with this technique on a 0.25 eV baseline resolution TES microcalorimeter designed for the ultra-high-resolution subarray of the Lynx mission. The line-shape was well described by a simple Gaussian. However, the difficulty of delivering photons to the small 46 µm square absorbers resulted in a large thermal crosstalk signal, whose random nature is expected to rapidly degrade the observed energy resolution towards higher photon numbers/energies. We have since improved the coupling between the optical fiber and the TES absorber and report here our current results.

6.
Phytother Res ; 34(10): 2493-2517, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32310327

ABSTRACT

Herbal treatments are often used as a treatment for migraine. Therefore, an evaluation of their safety and efficacy is important. Based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, and Cochrane Collaboration's tool for assessing the risk of bias, a systematic literature review of randomised, controlled human trials assessing the effects of herbal treatments delivered as a single ingredient for the acute or prophylactic treatment of migraine were conducted. Studies were identified through electronic database searches on Medline (Pubmed), Cochrane Library, Scopus, and CINAHL. Nineteen studies were identified examining the effects on migraine of feverfew, butterbur, curcumin, menthol/peppermint oil, coriander, citron, Damask rose, chamomile, and lavender. Overall, findings on the efficacy of feverfew were mixed and there was positive, albeit limited evidence for butterbur. There were positive, preliminary findings on curcumin, citron, and coriander as a prophylactic treatment for migraine, and the use of menthol and chamomile as an acute treatment. However, the risk of bias was high for many studies. The results of this systematic review suggest that several herbal medicines, via their multifactorial physiological influences, present as potential options to enhance the treatment of migraine. However, further high-quality research is essential to examine their efficacy and safety as a treatment for migraine.


Subject(s)
Migraine Disorders/drug therapy , Phytotherapy/methods , Plant Extracts/therapeutic use , Plants, Medicinal/physiology , Randomized Controlled Trials as Topic/statistics & numerical data , Acupuncture Therapy , Chamomile/physiology , Chemoprevention/methods , Citrus/physiology , Combined Modality Therapy , Coriandrum/physiology , Humans , Menthol/chemistry , Menthol/therapeutic use , Migraine Disorders/epidemiology , Music Therapy , Plants, Medicinal/chemistry , Randomized Controlled Trials as Topic/methods , Tanacetum parthenium/chemistry , Tanacetum parthenium/physiology
7.
Nature ; 504(7480): 394-400, 2013 Dec 19.
Article in English | MEDLINE | ID: mdl-24270812

ABSTRACT

To achieve its precise neural connectivity, the developing mammalian nervous system undergoes extensive activity-dependent synapse remodelling. Recently, microglial cells have been shown to be responsible for a portion of synaptic pruning, but the remaining mechanisms remain unknown. Here we report a new role for astrocytes in actively engulfing central nervous system synapses. This process helps to mediate synapse elimination, requires the MEGF10 and MERTK phagocytic pathways, and is strongly dependent on neuronal activity. Developing mice deficient in both astrocyte pathways fail to refine their retinogeniculate connections normally and retain excess functional synapses. Finally, we show that in the adult mouse brain, astrocytes continuously engulf both excitatory and inhibitory synapses. These studies reveal a novel role for astrocytes in mediating synapse elimination in the developing and adult brain, identify MEGF10 and MERTK as critical proteins in the synapse remodelling underlying neural circuit refinement, and have important implications for understanding learning and memory as well as neurological disease processes.


Subject(s)
Astrocytes/metabolism , Membrane Proteins/metabolism , Neural Pathways/metabolism , Phagocytosis , Proto-Oncogene Proteins/metabolism , Receptor Protein-Tyrosine Kinases/metabolism , Synapses/metabolism , Animals , Astrocytes/cytology , Brain/cytology , In Vitro Techniques , Lateral Thalamic Nuclei/cytology , Lateral Thalamic Nuclei/metabolism , Learning/physiology , Membrane Proteins/deficiency , Membrane Proteins/genetics , Mice , Mice, Transgenic , Neural Pathways/cytology , Proto-Oncogene Proteins/deficiency , Proto-Oncogene Proteins/genetics , Receptor Protein-Tyrosine Kinases/deficiency , Receptor Protein-Tyrosine Kinases/genetics , Retina/physiology , c-Mer Tyrosine Kinase
8.
Retina ; 39(3): 614-620, 2019 Mar.
Article in English | MEDLINE | ID: mdl-29232335

ABSTRACT

PURPOSE: To report the clinical features, treatment modalities, and visual outcomes in 12 eyes with endogenous Klebsiella pneumoniae endophthalmitis (EKPE). METHODS: The medical records of all patients diagnosed with EKPE at Stanford Hospital (Palo Alto, CA) and Santa Clara Valley County Hospital (Santa Clara, CA) from January 2000 to March 2017 were retrospectively reviewed. RESULTS: A total of 10 patients (12 eyes) were diagnosed with EKPE. The median age at presentation was 56, 80% were male, and 30% were non-Asian. Presenting visual acuities ranged from 20/20 to no light perception. Of the 12 eyes 10 received a tap and injection (range, 1-33 injections per eye), 2 eyes underwent primary enucleation or evisceration, and 1 patient underwent pars plana vitrectomy after tap and injection. Final visual acuities ranged from no light perception (six eyes) to 20/300 or better (five eyes). Five patients eventually underwent evisceration or enucleation. All cases were associated with positive blood and/or vitreous cultures and had concurrent systemic infection. CONCLUSION: Endogenous Klebsiella pneumoniae endophthalmitis is a rare, but devastating, ocular infection. Most cases in this series resulted in light perception vision or worse, and almost half required enucleation or evisceration. In light of the virulence of EKPE, early diagnosis and treatment should be initiated in all suspected cases.


Subject(s)
Endophthalmitis , Eye Infections, Bacterial , Klebsiella Infections , Klebsiella pneumoniae , Adult , Aged , Aged, 80 and over , Anti-Bacterial Agents/therapeutic use , California , Endophthalmitis/microbiology , Endophthalmitis/physiopathology , Endophthalmitis/therapy , Eye Enucleation , Eye Evisceration , Eye Infections, Bacterial/microbiology , Eye Infections, Bacterial/physiopathology , Eye Infections, Bacterial/therapy , Female , Humans , Klebsiella Infections/microbiology , Klebsiella Infections/physiopathology , Klebsiella Infections/therapy , Male , Middle Aged , Retrospective Studies , Visual Acuity/physiology , Vitrectomy
9.
BMC Biol ; 16(1): 98, 2018 09 06.
Article in English | MEDLINE | ID: mdl-30189863

ABSTRACT

Array tomography encompasses light and electron microscopy modalities that offer unparalleled opportunities to explore three-dimensional cellular architectures in extremely fine structural and molecular detail. Fluorescence array tomography achieves much higher resolution and molecular multiplexing than most other fluorescence microscopy methods, while electron array tomography can capture three-dimensional ultrastructure much more easily and rapidly than traditional serial-section electron microscopy methods. A correlative fluorescence/electron microscopy mode of array tomography furthermore offers a unique capacity to merge the molecular discrimination strengths of multichannel fluorescence microscopy with the ultrastructural imaging strengths of electron microscopy. This essay samples the first decade of array tomography, highlighting applications in neuroscience.


Subject(s)
Cytological Techniques/methods , Electron Microscope Tomography/methods , Imaging, Three-Dimensional/methods , Microscopy, Electron, Scanning/methods , Microscopy, Fluorescence/methods , Cytological Techniques/instrumentation , Electron Microscope Tomography/instrumentation , Imaging, Three-Dimensional/instrumentation , Microscopy, Electron, Scanning/instrumentation , Microscopy, Fluorescence/instrumentation
10.
Nat Methods ; 12(7): 671-8, 2015 Jul.
Article in English | MEDLINE | ID: mdl-26005811

ABSTRACT

The human cerebral cortex develops through an elaborate succession of cellular events that, when disrupted, can lead to neuropsychiatric disease. The ability to reprogram somatic cells into pluripotent cells that can be differentiated in vitro provides a unique opportunity to study normal and abnormal corticogenesis. Here, we present a simple and reproducible 3D culture approach for generating a laminated cerebral cortex-like structure, named human cortical spheroids (hCSs), from pluripotent stem cells. hCSs contain neurons from both deep and superficial cortical layers and map transcriptionally to in vivo fetal development. These neurons are electrophysiologically mature, display spontaneous activity, are surrounded by nonreactive astrocytes and form functional synapses. Experiments in acute hCS slices demonstrate that cortical neurons participate in network activity and produce complex synaptic events. These 3D cultures should allow a detailed interrogation of human cortical development, function and disease, and may prove a versatile platform for generating other neuronal and glial subtypes in vitro.


Subject(s)
Astrocytes/physiology , Cerebral Cortex/physiology , Pluripotent Stem Cells/cytology , Astrocytes/cytology , Cells, Cultured , Cerebral Cortex/cytology , Humans , Spheroids, Cellular , Synapses/physiology
11.
PLoS Comput Biol ; 13(4): e1005493, 2017 04.
Article in English | MEDLINE | ID: mdl-28414801

ABSTRACT

Deeper exploration of the brain's vast synaptic networks will require new tools for high-throughput structural and molecular profiling of the diverse populations of synapses that compose those networks. Fluorescence microscopy (FM) and electron microscopy (EM) offer complementary advantages and disadvantages for single-synapse analysis. FM combines exquisite molecular discrimination capacities with high speed and low cost, but rigorous discrimination between synaptic and non-synaptic fluorescence signals is challenging. In contrast, EM remains the gold standard for reliable identification of a synapse, but offers only limited molecular discrimination and is slow and costly. To develop and test single-synapse image analysis methods, we have used datasets from conjugate array tomography (cAT), which provides voxel-conjugate FM and EM (annotated) images of the same individual synapses. We report a novel unsupervised probabilistic method for detection of synapses from multiplex FM (muxFM) image data, and evaluate this method both by comparison to EM gold standard annotated data and by examining its capacity to reproduce known important features of cortical synapse distributions. The proposed probabilistic model-based synapse detector accepts molecular-morphological synapse models as user queries, and delivers a volumetric map of the probability that each voxel represents part of a synapse. Taking human annotation of cAT EM data as ground truth, we show that our algorithm detects synapses from muxFM data alone as successfully as human annotators seeing only the muxFM data, and accurately reproduces known architectural features of cortical synapse distributions. This approach opens the door to data-driven discovery of new synapse types and their density. We suggest that our probabilistic synapse detector will also be useful for analysis of standard confocal and super-resolution FM images, where EM cross-validation is not practical.


Subject(s)
Image Processing, Computer-Assisted/methods , Optical Imaging/methods , Synapses/physiology , Algorithms , Animals , Cerebral Cortex/diagnostic imaging , Computational Biology , Humans , Microscopy, Electron , Models, Statistical , Tomography
12.
Nature ; 486(7403): 410-4, 2012 May 27.
Article in English | MEDLINE | ID: mdl-22722203

ABSTRACT

In the developing central nervous system (CNS), the control of synapse number and function is critical to the formation of neural circuits. We previously demonstrated that astrocyte-secreted factors powerfully induce the formation of functional excitatory synapses between CNS neurons. Astrocyte-secreted thrombospondins induce the formation of structural synapses, but these synapses are postsynaptically silent. Here we use biochemical fractionation of astrocyte-conditioned medium to identify glypican 4 (Gpc4) and glypican 6 (Gpc6) as astrocyte-secreted signals sufficient to induce functional synapses between purified retinal ganglion cell neurons, and show that depletion of these molecules from astrocyte-conditioned medium significantly reduces its ability to induce postsynaptic activity. Application of Gpc4 to purified neurons is sufficient to increase the frequency and amplitude of glutamatergic synaptic events. This is achieved by increasing the surface level and clustering, but not overall cellular protein level, of the GluA1 subunit of the AMPA (α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid) glutamate receptor (AMPAR). Gpc4 and Gpc6 are expressed by astrocytes in vivo in the developing CNS, with Gpc4 expression enriched in the hippocampus and Gpc6 enriched in the cerebellum. Finally, we demonstrate that Gpc4-deficient mice have defective synapse formation, with decreased amplitude of excitatory synaptic currents in the developing hippocampus and reduced recruitment of AMPARs to synapses. These data identify glypicans as a family of novel astrocyte-derived molecules that are necessary and sufficient to promote glutamate receptor clustering and receptivity and to induce the formation of postsynaptically functioning CNS synapses.


Subject(s)
Astrocytes/metabolism , Excitatory Postsynaptic Potentials/physiology , Glypicans/metabolism , Receptors, AMPA/metabolism , Synapses/metabolism , Animals , Astrocytes/cytology , Cerebellum/cytology , Cerebellum/metabolism , Culture Media, Conditioned/metabolism , Culture Media, Conditioned/pharmacology , Female , Glypicans/deficiency , Glypicans/pharmacology , Hippocampus/cytology , Hippocampus/metabolism , Humans , Male , Mice , Mice, Inbred C57BL , Rats , Rats, Sprague-Dawley , Retinal Ganglion Cells/cytology , Retinal Ganglion Cells/drug effects , Retinal Ganglion Cells/metabolism , Synapses/drug effects , Synapses/pathology
13.
BMC Complement Altern Med ; 18(1): 98, 2018 Mar 20.
Article in English | MEDLINE | ID: mdl-29554961

ABSTRACT

BACKGROUND: To evaluate the efficacy and tolerability of a poly-herbal formulation, Herbagut, for the treatment of gastrointestinal symptoms and its effect on quality of life parameters in patients presenting with self-reported, unsatisfactory bowel habits. METHODS: This was a randomised, double-blind, placebo-controlled trial. Fifty adults with self-reported unsatisfactory bowel habits, primarily characterised by chronic constipation were randomly allocated to take Herbagut or a matching placebo for 28 days. Efficacy of gastrointestinal changes was measured by the completion of a patient daily diary evaluating changes in stool type (Bristol Stool Form Scale), ease of bowel movements, and feeling of complete evacuation; and the Gastrointestinal Symptom Rating Scale (GSRS). Changes in quality of life were also examined using the World Health Organization Quality of Life - abbreviated version (WHOQOL-BREF), and the Patient Assessment of Constipation-Quality of Life (PAC-QOL). RESULTS: All participants completed the 28-day trial with no adverse events reported. Compared to the placebo, weekly bowel movements increased over time (p < .001), as did self-reported, normal bowel motions (76% vs 4%; p < .001). Self-reported incomplete evacuation was also lower in the Herbagut group compared to placebo (24% vs 76%; p = <.001). GSRS domain ratings for abdominal pain, constipation, diarrhoea, indigestion, and reflux also decreased significantly in people taking Herbagut compared to placebo (p < .001, for all domains). Moreover, quality of life significantly improved in the Herbagut group compared to placebo as indicated by significantly greater improvement in WHOQOL-BREF domain ratings for overall quality of life, social relations, environmental health, psychological health, and physical health (p < .001, for all domains); and PAC-QOL domain ratings for physical discomfort, psychosocial discomfort, worries and concerns, and life satisfaction (p < .001, for all domains). The changes were considered clinically meaningful as evidenced by their large effect sizes. CONCLUSION: Herbagut ingestion over a 28-day period resulted in improvements in several gastrointestinal symptoms and overall quality of life. Further investigation utilising larger sample sizes and diverse clinical and cultural populations are needed. TRIAL REGISTRATION: Clinical Trials Registry- India /2016/11/007479 . Registered 24 April 2015 (retrospectively registered).


Subject(s)
Constipation/drug therapy , Plant Extracts/administration & dosage , Adult , Constipation/physiopathology , Defecation/drug effects , Double-Blind Method , Female , Gastrointestinal Tract/drug effects , Gastrointestinal Tract/physiopathology , Humans , India , Male , Middle Aged , Plants, Medicinal/chemistry , Quality of Life
14.
Emerg Infect Dis ; 23(9): 1590-1592, 2017 09.
Article in English | MEDLINE | ID: mdl-28820381

ABSTRACT

To inform Dracunculus medinensis (Guinea worm) eradication efforts, we evaluated the role of fish as transport hosts for Dracunculus worms. Ferrets fed fish that had ingested infected copepods became infected, highlighting the importance of recommendations to cook fish, bury entrails, and prevent dogs from consuming raw fish and entrails.


Subject(s)
Copepoda/parasitology , Dog Diseases/epidemiology , Dracunculiasis/epidemiology , Dracunculus Nematode/physiology , Ferrets/parasitology , Fish Diseases/epidemiology , Fishes/parasitology , Animals , Chad/epidemiology , Dog Diseases/parasitology , Dog Diseases/transmission , Dogs , Dracunculiasis/parasitology , Dracunculiasis/transmission , Dracunculus Nematode/pathogenicity , Fish Diseases/parasitology , Fish Diseases/transmission , Food Chain , Host Specificity , Humans , Larva/pathogenicity , Larva/physiology
15.
Nat Rev Neurosci ; 13(6): 365-79, 2012 May 10.
Article in English | MEDLINE | ID: mdl-22573027

ABSTRACT

Pioneering studies in the middle of the twentieth century revealed substantial diversity among mammalian chemical synapses and led to a widely accepted classification of synapse type on the basis of neurotransmitter molecule identity. Subsequently, powerful new physiological, genetic and structural methods have enabled the discovery of much deeper functional and molecular diversity within each traditional neurotransmitter type. Today, this deep diversity continues to pose both daunting challenges and exciting new opportunities for neuroscience. Our growing understanding of deep synapse diversity may transform how we think about and study neural circuit development, structure and function.


Subject(s)
Mammals/physiology , Synapses/chemistry , Synapses/physiology , Animals , Biodiversity , Humans , Memory/physiology , Nervous System Diseases/physiopathology , Neural Pathways/physiology , Neuronal Plasticity/physiology , Proteomics , Synapses/classification , Synaptic Transmission
16.
Brain ; 139(Pt 2): 468-80, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26685158

ABSTRACT

Ischaemic stroke is the leading cause of severe long-term disability yet lacks drug therapies that promote the repair phase of recovery. This repair phase of stroke occurs days to months after stroke onset and involves brain remapping and plasticity within the peri-infarct zone. Elucidating mechanisms that promote this plasticity is critical for the development of new therapeutics with a broad treatment window. Inhibiting tonic (extrasynaptic) GABA signalling during the repair phase was reported to enhance functional recovery in mice suggesting that GABA plays an important function in modulating brain repair. While tonic GABA appears to suppress brain repair after stroke, less is known about the role of phasic (synaptic) GABA during the repair phase. We observed an increase in postsynaptic phasic GABA signalling in mice within the peri-infarct cortex specific to layer 5; we found increased numbers of α1 receptor subunit-containing GABAergic synapses detected using array tomography, and an associated increased efficacy of spontaneous and miniature inhibitory postsynaptic currents in pyramidal neurons. Furthermore, we demonstrate that enhancing phasic GABA signalling using zolpidem, a Food and Drug Administration (FDA)-approved GABA-positive allosteric modulator, during the repair phase improved behavioural recovery. These data identify potentiation of phasic GABA signalling as a novel therapeutic strategy, indicate zolpidem's potential to improve recovery, and underscore the necessity to distinguish the role of tonic and phasic GABA signalling in stroke recovery.


Subject(s)
Drug Delivery Systems , GABA-A Receptor Agonists/administration & dosage , Neural Inhibition/physiology , Pyridines/administration & dosage , Receptors, GABA-A/physiology , Stroke/drug therapy , Animals , Drug Delivery Systems/trends , Male , Mice , Mice, Inbred C57BL , Neocortex/drug effects , Neocortex/physiology , Neural Inhibition/drug effects , Organ Culture Techniques , Recovery of Function/drug effects , Recovery of Function/physiology , Stroke/pathology , Stroke/physiopathology , Zolpidem
17.
J Neurosci ; 35(14): 5792-807, 2015 Apr 08.
Article in English | MEDLINE | ID: mdl-25855189

ABSTRACT

Synapses of the mammalian CNS are diverse in size, structure, molecular composition, and function. Synapses in their myriad variations are fundamental to neural circuit development, homeostasis, plasticity, and memory storage. Unfortunately, quantitative analysis and mapping of the brain's heterogeneous synapse populations has been limited by the lack of adequate single-synapse measurement methods. Electron microscopy (EM) is the definitive means to recognize and measure individual synaptic contacts, but EM has only limited abilities to measure the molecular composition of synapses. This report describes conjugate array tomography (AT), a volumetric imaging method that integrates immunofluorescence and EM imaging modalities in voxel-conjugate fashion. We illustrate the use of conjugate AT to advance the proteometric measurement of EM-validated single-synapse analysis in a study of mouse cortex.


Subject(s)
Brain Mapping , Electron Microscope Tomography , Neocortex/cytology , Neurons/ultrastructure , Synapses/ultrastructure , Animals , Dendrites/metabolism , Dendrites/ultrastructure , Image Processing, Computer-Assisted , Membrane Proteins/metabolism , Membrane Proteins/ultrastructure , Mice , Microscopy, Electron , Microtubules/ultrastructure , Nerve Tissue Proteins/metabolism , Nerve Tissue Proteins/ultrastructure , Neurons/metabolism , Regression Analysis , Support Vector Machine , Synapses/metabolism , Vesicular Glutamate Transport Proteins/metabolism , gamma-Aminobutyric Acid/metabolism
19.
Nutrients ; 16(11)2024 Jun 05.
Article in English | MEDLINE | ID: mdl-38892705

ABSTRACT

Background: Dietary quality and the consumption of antioxidant-rich foods have been shown to protect against memory decline. Therefore, this double-blind, randomized, placebo-controlled study aimed to investigate the effects of a nutritional supplement on changes in cognitive performance. Methods: In adults aged 40 to 70 years with subjective memory complaints, participants were randomly allocated to take a supplement containing vitamin E, astaxanthin, and grape juice extract daily for 12 weeks or a matching placebo. The primary outcomes comprised changes in cognitive tasks assessing episodic memory, working memory, and verbal memory. Secondary and exploratory measures included changes in the speed of information processing, attention, and self-report measures of memory, stress, and eye and skin health. Moreover, changes in plasma concentrations of brain-derived neurotrophic factor, malondialdehyde, tumor-necrosis factor-α, and interleukin-6 were measured, along with changes in skin carotenoid concentrations. Results: Compared to the placebo, nutritional supplementation was associated with larger improvements in one primary outcome measure comprising episodic memory (p = 0.037), but not for working memory (p = 0.418) or verbal learning (p = 0.841). Findings from secondary and exploratory outcomes demonstrated that the nutraceutical intake was associated with larger improvements in the Everyday Memory Questionnaire (p = 0.022), increased plasma brain-derived neurotrophic factor (p = 0.030), decreased plasma malondialdehyde (p = 0.040), and increased skin carotenoid concentrations (p = 0.006). However, there were no group differences in changes in the remaining outcome measures. Conclusions: Twelve weeks of supplementation with a nutritional supplement was associated with improvements in episodic memory and several biological markers associated with cognitive health. Future research will be essential to extend and validate the current findings.


Subject(s)
Brain-Derived Neurotrophic Factor , Cognition , Dietary Supplements , Humans , Middle Aged , Double-Blind Method , Male , Female , Cognition/drug effects , Adult , Aged , Brain-Derived Neurotrophic Factor/blood , Vitamin E , Xanthophylls/administration & dosage , Skin/drug effects , Antioxidants , Interleukin-6/blood , Self Report , Carotenoids/blood , Tumor Necrosis Factor-alpha/blood , Memory, Short-Term/drug effects , Memory, Episodic , Fruit and Vegetable Juices , Malondialdehyde/blood , Eye/drug effects
20.
Ophthalmology ; 120(7): 1492-6, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23531348

ABSTRACT

PURPOSE: To report a diplopia questionnaire (DQ) with a data-driven scoring algorithm. DESIGN: Cross-sectional study. PARTICIPANTS: To optimize questionnaire scoring, 147 adults with diplopic strabismus completed both the DQ and the Adult Strabismus-20 (AS-20) health-related quality-of-life (HRQOL) questionnaire. To assess test-retest reliability, 117 adults with diplopic strabismus. To assess responsiveness to surgery, 42 adults (46 surgeries). METHODS: The 10-item AS-20 function subscale score (scored 0-100) was defined as the gold standard for severity. A range of weights was assigned to the responses and the gaze positions (from equal weighting to greater weighting of primary and reading). Combining all response option weights with all gaze position weights yielded 382848 scoring algorithms. We then calculated 382848 Spearman rank correlation coefficients comparing each algorithm with the AS-20 function subscale score. MAIN OUTCOME MEASURES: To optimize scoring, Spearman rank correlation coefficients (measuring agreement) between DQ scores and AS-20 function subscale scores. For test-retest reliability, 95% limits of agreement and intraclass correlation coefficient (ICC). For responsiveness, change in DQ score. RESULTS: For the 382 848 possible scoring algorithms, correlations with AS-20 function subscale score ranged from -0.64 (best correlated) to -0.55. The best-correlated algorithm had response option weights of 5 for rarely, 50 for sometimes, and 75 for often, and gaze position weights of 40 for straight ahead in the distance, 40 for reading, 1 for up, 8 for down, 4 for right, 4 for left, and 3 for other, totaling 100. There was excellent test-retest reliability with an ICC of 0.89 (95% confidence interval, 0.84-0.92), and 95% limits of agreement were 30.9 points. The DQ score was responsive to surgery with a mean change of 51 ± 34 (P<0.001). CONCLUSIONS: We have developed a data-driven scoring algorithm for the DQ, rating diplopia symptoms from 0 to 100. On the basis of correlations with HRQOL, straight-ahead and reading positions should be highly weighted. The DQ has excellent test-retest reliability and responsiveness, and may be useful in both clinical and research settings.


Subject(s)
Diplopia/diagnosis , Disability Evaluation , Sickness Impact Profile , Surveys and Questionnaires , Adolescent , Adult , Aged , Aged, 80 and over , Algorithms , Child , Cross-Sectional Studies , Female , Humans , Male , Middle Aged , Quality of Life , Reproducibility of Results , Severity of Illness Index , Young Adult
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