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1.
bioRxiv ; 2024 Jan 02.
Article in English | MEDLINE | ID: mdl-38313256

ABSTRACT

Glioblastoma (GBM) is a malignant brain tumor with uncontrolled invasive growth. Here, we demonstrate how GBM cells usurp guidance receptor Plexin-B2 to gain biomechanical plasticity for polarized migration through confined space. Using live-cell imaging to track GBM cells negotiating microchannels, we reveal active endocytosis at cell front and filamentous actin assembly at rear to propel GBM cells through constrictions. These two processes are interconnected and governed by Plexin-B2 that orchestrates cortical actin and membrane tension, shown by biomechanical assays. Molecular dynamics simulations predict that balanced membrane and actin tension are required for optimal migratory velocity and consistency. Furthermore, Plexin-B2 mechanosensitive function requires a bendable extracellular ring structure and affects membrane internalization, permeability, phospholipid composition, as well as inner membrane surface charge. Together, our studies unveil a key element of membrane tension and mechanoelectrical coupling via Plexin-B2 that enables GBM cells to adapt to physical constraints and achieve polarized confined migration.

2.
Autophagy Rep ; 2(1)2023.
Article in English | MEDLINE | ID: mdl-37637387

ABSTRACT

The Schlemm's canal (SC) is a circular, lymphatic-like vessel located at the limbus of the eye that participates in the regulation of aqueous humor drainage to control intraocular pressure (IOP). Circumferential flow of aqueous humor within the SC lumen generates shear stress, which regulates SC cell behaviour. Using biochemical analysis and real-time live cell imaging techniques, we have investigated the activation of autophagy in SC cells by shear stress. We report, for the first time, the primary cilium (PC)-dependent activation of autophagy in SC cells in response to shear stress. Moreover, we identified PC-dependent shear stress-induced autophagy to be positively regulated by phosphorylation of SMAD2 in its linker and C-terminal regions. Additionally, SMAD2/3 signaling was found to transcriptionally activate LC3B, ATG5 and ATG7 in SC cells. Intriguingly, concomitant to SMAD2-dependent activation of autophagy, we also report here the activation of mTOR pathway, a classical autophagy inhibitor, in SC cells by shear stress. mTOR activation was found to also be dependent on the PC. Moreover, pharmacological inhibition of class I PI3K increased phosphorylation of SMAD2 at the linker and activated autophagy. Together, our data indicates an interplay between PI3K and SMAD2/3 signaling pathways in the regulation of PC-dependent shear stress-induced autophagy in SC cells.

3.
Cell Death Dis ; 14(8): 554, 2023 08 24.
Article in English | MEDLINE | ID: mdl-37620383

ABSTRACT

Glaucoma is a group of diseases that leads to chronic degeneration of retinal ganglion cell (RGC) axons and progressive loss of RGCs, resulting in vision loss. While aging and elevated intraocular pressure (IOP) have been identified as the main contributing factors to glaucoma, the molecular mechanisms and signaling pathways triggering RGC death and axonal degeneration are not fully understood. Previous studies in our laboratory found that overactivation of autophagy in DBA/2J::GFP-LC3 mice led to RGC death and optic nerve degeneration with glaucomatous IOP elevation. We found similar findings in aging GFP-LC3 mice subjected to chronic IOP elevation. Here, we further investigated the impact of autophagy deficiency on autophagy-deficient DBA/2J-Atg4bko and DBA/2J-Atg4b+/- mice, generated in our laboratory via CRISPR/Cas9 technology; as well as in Atg4bko mice subjected to the experimental TGFß2 chronic ocular hypertensive model. Our data shows that, in contrast to DBA/2J and DBA/2J-Atg4b+/- littermates, DBA/2J-Atg4bko mice do not develop glaucomatous IOP elevation. Atg4b deficiency also protected against glaucomatous IOP elevation in the experimental TGFß2 chronic ocular hypertensive model. Atg4 deletion did not compromise RGC or optic nerve survival in Atg4bko mice. Moreover, our results indicate a protective role of autophagy deficiency against RGC death and ON atrophy in the hypertensive DBA/2J-Atg4b+/- mice. Together, our data suggests a pathogenic role of autophagy activation in ocular hypertension and glaucoma.


Subject(s)
Glaucoma , Ocular Hypertension , Animals , Mice , Mice, Inbred DBA , Glaucoma/complications , Glaucoma/genetics , Autophagy/genetics , Disease Models, Animal , Retinal Ganglion Cells
4.
Am J Law Med ; 49(2-3): 234-249, 2023 Jul.
Article in English | MEDLINE | ID: mdl-38344796

ABSTRACT

When federal district court Judge Carlton Reeves penned his opinion in U.S. v. Mississippi,1 the case that seemed poised to overhaul Mississippi's suffering mental health system, he began with the story of Ms. Melanie Worsham, a mental health patient, also a certified peer support specialist. Ms. Worsham works to help those like herself who suffer with lifelong serious mental illness (SMI) to "overcome the obstacles that might be getting in their way of living the life they want to live." She also assists those with SMI by aiding in "navigating the system, to find resources, and then just being moral support."2.


Subject(s)
Persons with Mental Disabilities , Humans , Mississippi , United States , Persons with Mental Disabilities/legislation & jurisprudence , Supreme Court Decisions
5.
Materials (Basel) ; 15(13)2022 Jun 29.
Article in English | MEDLINE | ID: mdl-35806714

ABSTRACT

Mosquitoes are commonly viewed as pests and deadly predators by humans. Despite this perception, investigations of their survival-based behaviors, select anatomical features, and biological composition have led to the creation of several beneficial technologies for medical applications. In this review, we briefly explore these mosquito-based innovations by discussing how unique characteristics and behaviors of mosquitoes drive the development of select biomaterials and medical devices. Mosquito-inspired microneedles have been fabricated from a variety of materials, including biocompatible metals and polymers, to mimic of the mouthparts that some mosquitoes use to bite a host with minimal injury during blood collection. The salivary components that these mosquitoes use to reduce the clotting of blood extracted during the biting process provide a rich source of anticoagulants that could potentially be integrated into blood-contacting biomaterials or administered in therapeutics to reduce the risk of thrombosis. Mosquito movement, vision, and olfaction are other behaviors that also have the potential for inspiring the development of medically relevant technologies. For instance, viscoelastic proteins that facilitate mosquito movement are being investigated for use in tissue engineering and drug delivery applications. Even the non-wetting nanostructure of a mosquito eye has inspired the creation of a robust superhydrophobic surface coating that shows promise for biomaterial and drug delivery applications. Additionally, biosensors incorporating mosquito olfactory receptors have been built to detect disease-specific volatile organic compounds. Advanced technologies derived from mosquitoes, and insects in general, form a research area that is ripe for exploration and can uncover potential in further dissecting mosquito features for the continued development of novel medical innovations.

6.
SSM Popul Health ; 18: 101113, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35664925

ABSTRACT

Despite well-documented evidence illustrating the relationship between discrimination and health, less is known about the influence of unfair treatment when receiving medical care. Moreover, our current knowledge of cross-national and racial variations in healthcare discrimination is limited in aging populations. This article addresses these gaps using two harmonized data sets of aging populations to clarify the relationship between healthcare discrimination and health in the United States and Brazil. We use nationally representative, harmonized data from the Health and Retirement Study in the United States and the Brazilian Longitudinal Study of Aging to examine and compare perceived discrimination in the healthcare setting and its relationship to self-rated health, depression diagnosis, and depressive symptoms across national contexts. Using Poisson regression models and population attributable risk percent estimates, we found that aging adults reporting healthcare discrimination were at higher risk of poor self-rated health, diagnosed depression, and depressive symptoms. Our results also suggest that reducing perceived healthcare discrimination may contribute to improved self-rated health and mental well-being in later life across racialized societies. In two comparative settings, we highlight the differential impact of healthcare discrimination on self-rated health and depression. We describe the implications of our study's findings for national public health strategies focused on eliminating discrimination in the healthcare setting, particularly among aging countries.

7.
Biomed Microdevices ; 24(1): 8, 2022 01 04.
Article in English | MEDLINE | ID: mdl-34982244

ABSTRACT

While there are many chip models that simulate the air-tissue interface of the respiratory system, only a few represent the upper respiratory system. These chips are restricted to unidirectional flow patterns that are not comparable to the highly dynamic and variable flow patterns found in the native nasal cavity. Here we describe the development of a tunable nose-on-chip device that mimics the air-mucosa interface and is coupled to an air delivery system that simulates natural breathing patterns through the generation of bi-directional air flow. Additionally, we employ computational modeling to demonstrate how the device design can be tuned to replicate desired mechanical characteristics within specific regions of the human nasal cavity. We also demonstrate how to culture human nasal epithelial cell line RPMI 2650 within the lab-on-chip (LOC) device. Lastly, Alcian Blue histological staining was performed to label mucin proteins, which play important roles in mucous secretion. Our results revealed that dynamic flow conditions can increase mucous secretion for RPMI 2650 cells, when compared to no flow, or stationary, conditions.


Subject(s)
Nasal Cavity , Proteins , Computer Simulation , Humans , Printing, Three-Dimensional , Stress, Mechanical
8.
Proc Natl Acad Sci U S A ; 118(13)2021 03 30.
Article in English | MEDLINE | ID: mdl-33753495

ABSTRACT

Activation of autophagy is one of the responses elicited by high intraocular pressure (IOP) and mechanical stretch in trabecular meshwork (TM) cells. However, the mechanosensor and the molecular mechanisms by which autophagy is induced by mechanical stretch in these or other cell types is largely unknown. Here, we have investigated the mechanosensor and downstream signaling pathway that regulate cyclic mechanical stretch (CMS)-induced autophagy in TM cells. We report that primary cilia act as a mechanosensor for CMS-induced autophagy and identified a cross-regulatory talk between AKT1 and noncanonical SMAD2/3 signaling as critical components of primary cilia-mediated activation of autophagy by mechanical stretch. Furthermore, we demonstrated the physiological significance of our findings in ex vivo perfused eyes. Removal of primary cilia disrupted the homeostatic IOP compensatory response and prevented the increase in LC3-II protein levels in response to elevated pressure challenge, strongly supporting a role of primary cilia-mediated autophagy in regulating IOP homeostasis.


Subject(s)
Cilia/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Smad2 Protein/metabolism , Smad3 Protein/metabolism , Trabecular Meshwork/metabolism , Autophagy , Cells, Cultured , Cilia/pathology , Gene Knockdown Techniques , Humans , Intraocular Pressure/physiology , Intravital Microscopy , Mechanotransduction, Cellular/genetics , Ocular Hypertension/pathology , Ocular Hypertension/physiopathology , Primary Cell Culture , Proto-Oncogene Proteins c-akt/genetics , Smad2 Protein/genetics , Smad3 Protein/genetics , Stress, Mechanical , Time-Lapse Imaging , Trabecular Meshwork/cytology , Trabecular Meshwork/pathology
9.
J Clin Med ; 10(1)2020 Dec 28.
Article in English | MEDLINE | ID: mdl-33379277

ABSTRACT

Extracellular matrix (ECM) deposition in the trabecular meshwork (TM) is one of the hallmarks of glaucoma, a group of human diseases and leading cause of permanent blindness. The molecular mechanisms underlying ECM deposition in the glaucomatous TM are not known, but it is presumed to be a consequence of excessive synthesis of ECM components, decreased proteolytic degradation, or both. Targeting ECM deposition might represent a therapeutic approach to restore outflow facility in glaucoma. Previous work conducted in our laboratory identified the lysosomal enzyme cathepsin B (CTSB) to be expressed on the cellular surface and to be secreted into the culture media in trabecular meshwork (TM) cells. Here, we further investigated the role of CTSB on ECM remodeling and outflow physiology in vitro and in CSTBko mice. Our results indicate that CTSB localizes in the caveolae and participates in the pericellular degradation of ECM in TM cells. We also report here a novel role of CTSB in regulating the expression of PAI-1 and TGFß/Smad signaling in TM cells vitro and in vivo in CTSBko mice. We propose enhancing CTSB activity as a novel therapeutic target to attenuate fibrosis and ECM deposition in the glaucomatous outflow pathway.

10.
Invest Ophthalmol Vis Sci ; 61(10): 31, 2020 08 03.
Article in English | MEDLINE | ID: mdl-32797200

ABSTRACT

Purpose: To investigate autophagy in the outflow pathway and ganglion cell layer in the aging and ocular hypertensive mouse. Methods: Both 4-month-old and 18-month-old C57BL/6J and GFP-LC3 mice were subjected to unilateral injection of hypertonic saline into a limbal vein, causing sclerosis of the outflow pathway and subsequent elevation of intraocular pressure (IOP). IOP was measured on a weekly basis using a rebound tonometer. Protein expression levels of LC3B, Lamp1, and p62 were evaluated by western blot and/or immunofluorescence. Retinal ganglion cell (RGC) count was performed in whole retinal flat mounts using an anti-Brn3a antibody. Optic nerves were fixed with 4% paraformaldehyde and resin-embedded for axon counts and electron microscopy. Results: In contrast to 18-month-old mice, which developed sustained elevated IOP with a single injection, 4-month-old mice were refractory to high elevations of IOP. Interestingly, both the percentage of animals that developed elevated IOP and the mean ∆IOP were significantly higher in the transgenic mice compared to C57BL/6J. Immunofluorescence and western blot analysis showed dysregulated autophagy in the iridocorneal and retina tissues from 18-month-old mice compared to 4-month-old ones. Moreover, the LC3-II/LC3-I ratio correlated with IOP. As expected, injected hypertensive eyes displayed axonal degeneration and RGC death. RGC and axon loss were significantly exacerbated with aging, especially when combined with GFP-LC3 expression. Autophagic structures were observed in the degenerating axons. Conclusions: Our results indicate dysregulation of autophagy in the trabecular meshwork and retinal tissues with aging and suggest that such dysregulation of autophagy contributes to neurodegeneration in glaucoma.


Subject(s)
Aging , Autophagy , Ocular Hypertension/metabolism , Aging/metabolism , Animals , Blotting, Western , Disease Models, Animal , Female , Fluorescent Antibody Technique , Green Fluorescent Proteins , Intraocular Pressure , Male , Mice , Mice, Inbred C57BL , Mice, Transgenic , Ocular Hypertension/pathology , Optic Nerve/pathology , Retinal Ganglion Cells/metabolism , Retinal Ganglion Cells/pathology , Trabecular Meshwork/metabolism , Trabecular Meshwork/pathology
11.
Sci Rep ; 9(1): 20036, 2019 Dec 27.
Article in English | MEDLINE | ID: mdl-31882735

ABSTRACT

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

12.
Sci Rep ; 9(1): 16265, 2019 11 07.
Article in English | MEDLINE | ID: mdl-31700007

ABSTRACT

Effective personalized therapeutic treatment for hearing loss is currently not available. Cochlear oxidative stress is commonly identified in the pathogenesis of hearing loss based upon findings from excised tissue, thus suggesting a promising druggable etiology. However, the timing and site(s) to target for anti-oxidant treatment in vivo are not clear. Here, we address this long-standing problem with QUEnch-assiSTed Magnetic Resonance Imaging (QUEST MRI), which non-invasively measures excessive production of free radicals without an exogenous contrast agent. QUEST MRI is hypothesized to be sensitive to noise-evoked cochlear oxidative stress in vivo. Rats exposed to a loud noise event that resulted in hair cell loss and reduced hearing capability had a supra-normal MRI R1 value in their cochleae that could be corrected with anti-oxidants, thus non-invasively indicating cochlear oxidative stress. A gold-standard oxidative damage biomarker [heme oxidase 1 (HO-1)] supported the QUEST MRI result. The results from this study highlight QUEST MRI as a potentially transformative measurement of cochlear oxidative stress in vivo that can be used as a biomarker for improving individual evaluation of anti-oxidant treatment efficacy in currently incurable oxidative stress-based forms of hearing loss.

13.
Soc Sci Res ; 79: 32-55, 2019 03.
Article in English | MEDLINE | ID: mdl-30857667

ABSTRACT

Despite competing narratives of mestizaje (race-mixing) emphasizing class discrimination and social movements highlighting the existence of racial discrimination in Latin America, little work has examined the overlap of class and color in people's understandings of discrimination. This study moves beyond the color/class binary by examining perceptions of only class, only color, and both class and color discrimination (dual discrimination). I also examine whether individuals have difficulty attributing the causes of discrimination by expanding upon the social psychological concept of attributional ambiguity. Using nationally representative data from the 2010 LAPOP's Americas Barometer survey, I find that color-based explanations have not replaced class-based explanations. Instead, both class and color appear to be part of schemas drawn upon by individuals to understand the unfavorable treatment they perceive-in line with scholarship showing both class disadvantage and color conjointly influence the stratification systems of Latin America. There is also suggestive evidence that individuals may have trouble disentangling the causes of the discrimination they perceive.


Subject(s)
Prejudice , Racism , Social Class , Adult , Cross-Sectional Studies , Female , Humans , Latin America , Male , Racism/psychology , Socioeconomic Factors , Vulnerable Populations/psychology
14.
JAMA Netw Open ; 2(3): e190874, 2019 03 01.
Article in English | MEDLINE | ID: mdl-30901044

ABSTRACT

Importance: Febrile neonates (persons in the first month of life) are believed to be at higher risk for bacteremia or bacterial meningitis than infants in their second month of life. However, the true prevalence is unclear. Objective: To determine modern rates of bacteremia and bacterial meningitis in febrile neonates and infants in the second month of life presenting to an ambulatory setting. Data Sources: A comprehensive, no-limit search was conducted in PubMed using previously published search terms in February 2015 and repeated in September 2016. Study Selection: Abstracts and full texts were reviewed independently by several investigators. Studies were included if data regarding blood cultures or cerebrospinal fluid cultures from consecutive febrile infants in an ambulatory setting could be extrapolated within the age groups. To limit the analysis to the period after the availability of the Haemophilus influenzae type b vaccination, studies that collected data before 1990 were excluded. Data Extraction and Synthesis: Data were extracted in accordance with the Meta-analyses of Observational Studies in Epidemiology (MOOSE) reporting guidelines via independent abstraction by several investigators. The Newcastle-Ottawa Scale was used to assess bias. Main Outcomes and Measures: The primary outcomes were prevalence rates of bacteremia and bacterial meningitis in febrile neonates and infants in the second month of life. In neonates, prevalence rates were also estimated in the era of group B Streptococcus intrapartum antibiotic prophylaxis (after 1996). Results: In total, 7264 abstracts were screened, resulting in 188 full-text manuscripts reviewed, with 12 meeting inclusion criteria (with 15 713 culture results). For febrile neonates, the prevalence of bacteremia was 2.9% (95% CI, 2.3%-3.7%; I2 = 50%; n = 5145) and the prevalence of bacterial meningitis was 1.2% (95% CI, 0.8%-1.9%; I2 = 27%; n = 3288). In neonates in the era after group B Streptococcus prophylaxis, the prevalence of bacteremia was 3.0% (95% CI, 2.3%-3.9%; I2 = 6%; n = 2055) and the prevalence of meningitis was 1.0% (95% CI, 0.4%-2.1%; I2 = 28%; n = 1739). For febrile infants in the second month of life, the prevalence of bacteremia was 1.6% (95% CI, 0.9%-2.7%; I2 = 78%; n = 4778) and the prevalence of meningitis was 0.4% (95% CI, 0.2%-1.0%; I2 = 33%; n = 2502). Conclusions and Relevance: These findings suggest that febrile neonates have approximately twice the rate of bacteremia and meningitis as febrile infants in their second month of life.


Subject(s)
Bacteremia/epidemiology , Fever/complications , Fever/epidemiology , Infant, Newborn, Diseases/epidemiology , Meningitis, Bacterial/epidemiology , Bacteremia/complications , Humans , Infant , Infant, Newborn , Meningitis, Bacterial/complications , Prevalence
15.
Neurosci Lett ; 703: 58-67, 2019 06 11.
Article in English | MEDLINE | ID: mdl-30885631

ABSTRACT

Burgeoning use of segregated microfluidic platforms that parse somas and neurites into discrete compartments is fueling unique examinations of neuronal structure and physiology in a manner impossible to achieve with non-compartmentalized systems. However, even though this line of axon-soma polarizing microfluidic devices stems from the same general design of a Campenot chamber set-up, slight deviations in device geometry appear to induce vastly different nutrient transport profiles that influence neuron survival and maturation. Here we examine the uptake of nerve growth factor (NGF) by a pheochromocytoma PC12 cell line cultured using two Campenot-like device designs, a "Standard" layout, representative of a commercial device, and a custom "Notch" layout, predicted to encourage more efficient nutrient transfer that gives rise to sustained neuron viability and extensive neurite elaboration. Exploiting in vitro culture schemes coupled with computational analyses, we identify the influence of device design geometry on the interplay between neuronal survival and maturation, gauged from morphometric assessments and the spatiotemporal distribution of NGF. Computer simulations of NGF transport within the devices revealed that the microfluidic neuron culture system is highly sensitive to change, where nutrient transport is intricately linked to device geometry and cell plating density, and premature depletion of nutrients is observed if specific design criteria are not met. This study underscores the importance of validating specific device geometries for a particular neuro-based assessment, while showcasing computational modeling as a powerful tool to achieve this goal.


Subject(s)
Lab-On-A-Chip Devices , Nerve Growth Factor/metabolism , Neurons/cytology , Animals , Cell Culture Techniques , Cell Differentiation , Cell Survival , Computer Simulation , Diffusion , Neurons/metabolism , PC12 Cells , Rats
16.
Biomaterials ; 186: 44-63, 2018 12.
Article in English | MEDLINE | ID: mdl-30278345

ABSTRACT

Over the past two decades, a number of fabrication methods, including 3D printing and bioprinting, have emerged as promising technologies to bioengineer nerve conduits that closely replicate features of the native peripheral nerve, with the aim of augmenting or supplanting autologous nerve grafts. 3D printing and bioprinting offer the added advantage of rapidly creating composite peripheral nerve matrices from micron-scaled units, using an assortment of synthetic, natural and biologic materials. In this review, we explore the evolution of automated 3D manufacturing technologies for the development of peripheral nerve conduits and discuss aspects of conduit design, based on microarchitecture, material selection, cell and protein inclusion, and mechanical properties, as they are adaptable to 3D printing. Additionally, we highlight advancements in the application of bio-imaging modalities toward the fabrication of patient-specific nerve conduits. Lastly, we outline regulatory as well as clinical challenges that must be surmounted for the translation of 3D printing and bioprinting technology to the clinic. As a whole, this review addresses topics that may situate 3D manufacturing at the forefront of fabrication technologies that are exploited for the generation of future revolutionary therapies like in situ printing of peripheral nerves.


Subject(s)
Nerve Regeneration , Peripheral Nerves/transplantation , Printing, Three-Dimensional , Animals , Biocompatible Materials/chemistry , Bioprinting/methods , Electric Conductivity , Humans , Polymers/chemistry , Tissue Engineering/methods , Tissue Scaffolds/chemistry
17.
Cell Death Discov ; 4: 14, 2018.
Article in English | MEDLINE | ID: mdl-30210817

ABSTRACT

Glaucoma is a progressive optic neuropathy characterized by axonal degeneration and retinal ganglion cells loss. Several factors have been postulated to play a role in glaucoma, elevated intraocular pressure (IOP) being the best well-known causative factor. The mechanisms leading to ocular hypertension and glaucoma are still not fully understood. An increasing number of evidence indicates a role of autophagy in the pathophysiological process of ocular hypertension and glaucoma. However, while all of the studies agree that autophagy is induced in RGCs in response to injury, autophagy was found to either protect or promote cell death depending on the experimental model used. In order to gain more insight into both, the role of autophagy in the pathogenesis of glaucoma and the effect of chronic IOP elevation in the autophagy pathway, we have investigated here for the first time autophagy in the iridocorneal angle region, retinal ganglion cell bodies, and ON axons in the spontaneous ocular hypertensive DBA/2J mouse glaucoma model and in the transgenic DBA/2J::GFP-LC3 mice, generated in our laboratory. Our results indicate decreased autophagic flux in the outflow pathway cells in the DBA/2J mice, characterized by increased levels of LC3-II and p62 together with a decrease in the lysosomal marker LAMP1, evaluated by western blot and immunofluorescence. Elevated presence of autophagic vacuoles in the DBA/2J and, in particular, in the DBA/2J::GFP-LC3 mice was also observed. Expression of the GFP-LC3 transgene was associated to higher cumulative IOP in the DBA/2J background. In addition to higher elevation in IOP, DBA/2J::GFP-LC3 were characterized by further RGCs and exacerbated axonal degeneration compared to DBA/2J. This was accompanied by the notable high presence of autophagic figures within degenerating axons. These results strongly suggest overactivation of autophagy as a potential cellular mechanism leading to ON degeneration in the chronic hypertensive DBA/2J mice.

18.
Nanomedicine ; 14(7): 1999-2008, 2018 10.
Article in English | MEDLINE | ID: mdl-29665440

ABSTRACT

Fundamental challenges of targeting specific brain regions for treatment using pharmacotherapeutic nanoparticle (NP) carriers include circumventing the blood-brain-barrier (BBB) and tracking delivery. Angiopep-2 (AP2) has been shown to facilitate the transport of large macromolecules and synthetic nanoparticles across the BBB. Thus, conjugation of AP2 to an MS2 bacteriophage based NP should also permit transport across the BBB. We have fabricated and tested a novel MS2 capsid-based NP conjugated to the ligand AP2. The reaction efficiency was determined to be over 70%, with up to two angiopep-2 conjugated per MS2 capsid protein. When linked with a porphyrin ring, manganese (Mn2+) remained stable within MS2 and was MRI detectable. Nanoparticles were introduced intracerebroventricularly or systemically. Systemic delivery yielded dose dependent, non-toxic accumulation of NPs in the midbrain. Design of a multifunctional MRI compatible NP platform provides a significant step forward for the diagnosis and treatment of intractable brain conditions, such as tinnitus.


Subject(s)
Blood-Brain Barrier/drug effects , Brain/drug effects , Levivirus/chemistry , Magnetic Resonance Imaging , Nanoparticles/administration & dosage , Peptides/chemistry , Tinnitus/drug therapy , Animals , Biological Transport , Drug Carriers , Drug Delivery Systems , Male , Nanoparticles/chemistry , Rats , Rats, Sprague-Dawley
19.
J Clin Child Adolesc Psychol ; 47(2): 296-311, 2018.
Article in English | MEDLINE | ID: mdl-26998803

ABSTRACT

Acceptance and Commitment Therapy (ACT) has a growing empirical base in the treatment of anxiety among adults and children with other concerns. This study reports on the main outcomes of a randomized controlled trial of ACT and traditional cognitive behavioral therapy (CBT) in children with a Diagnostic and Statistical Manual of Mental Disorders (4th ed.) anxiety disorder. Participants were 193 children from urban Sydney, Australia, who were block-randomized to a 10-week group-based program of ACT or CBT or a 10-week waitlist control (WLC). Completers included 157 children (ACT = 54, CBT = 57, WLC = 46; M = 11 years, SD = 2.76; 78% Caucasian, 58% female). Pretreatment, posttreatment, and 3 months posttreatment assessments included clinician/self/parent-reported measures of anxiety, quality of life (QOL; anxiety interference, psychosocial and physical health-related QOL), and acceptance/defusion outcomes. Completer and intention-to-treat analyses revealed that ACT and CBT were both superior to WLC across outcomes, reflecting statistically and clinically significant differences, with gains maintained at 3 months posttreatment. Both completer and intention-to-treat analyses found ACT and CBT to produce similar outcomes. There was some support for ACT having greater effect sizes for QOL outcomes but not for avoidance/fusion. Although this study does not suggest that ACT is equivalent to CBT or should be adopted in its place, it does provide evidence that ACT might be another empirically supported treatment option for anxious youth. Further research is needed to replicate these findings.


Subject(s)
Acceptance and Commitment Therapy/methods , Anxiety/psychology , Cognitive Behavioral Therapy/methods , Quality of Life/psychology , Adolescent , Child , Female , Humans , Male , Treatment Outcome
20.
J Tissue Eng Regen Med ; 12(1): e379-e383, 2018 01.
Article in English | MEDLINE | ID: mdl-27943657

ABSTRACT

New therapeutic approaches for repairing an injured or degenerating nervous system have accelerated the development of methods to generate populations of neurons derived from various stem cell sources efficiently. Many of these methods require the generation of neurospheres. Here a simple technique is described for creating an array of adherent mouse embryonic stem cell (mESC)-derived neurospheres using a conventional plastic culture dish and a patterning template. mESC-derived neurospheres are confined to circular (4-mm diameter), gel-coated regions within an array. The adherent neurosphere arrays require 3 days to prepare from an mESC source; they can be maintained in 15 µl drops of medium, and exhibit extensive neurite elaboration after 8 days of cultivation. Additionally, the potential of treating the adherent neurospheres in selected drops of an array is demonstrated with a variety of differentiation-inducing reagents and subsequently individually analysing such neurospheres for gene expression, protein levels and morphological development. Copyright © 2016 John Wiley & Sons, Ltd.


Subject(s)
Cell Culture Techniques/methods , Mouse Embryonic Stem Cells/cytology , Neurons/cytology , Spheroids, Cellular/cytology , Animals , Cell Adhesion , Mice , Neurites/metabolism , Neurons/metabolism , Spheroids, Cellular/metabolism
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