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3.
Sci Rep ; 12(1): 5644, 2022 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-35379876

RESUMO

Translation of the hexanucleotide G4C2 expansion associated with C9orf72 amyotrophic lateral sclerosis and frontotemporal dementia (ALS/FTD) produces five different dipeptide repeat protein (DPR) species that can confer toxicity. There is yet much to learn about the contribution of a single DPR to disease pathogenesis. We show here that a short repeat length is sufficient for the DPR poly-GR to confer neurotoxicity in vitro, a phenomenon previously unobserved. This toxicity is also reported in vivo in our novel knock-in mouse model characterized by widespread central nervous system (CNS) expression of the short-length poly-GR. We observe sex-specific chronic ALS/FTD-like phenotypes in these mice, including mild motor neuron loss, but no TDP-43 mis-localization, as well as motor and cognitive impairments. We suggest that this model can serve as the foundation for phenotypic exacerbation through second-hit forms of stress.


Assuntos
Esclerose Lateral Amiotrófica , Demência Frontotemporal , Esclerose Lateral Amiotrófica/metabolismo , Animais , Arginina/genética , Proteína C9orf72/genética , Proteína C9orf72/metabolismo , Dipeptídeos/metabolismo , Feminino , Demência Frontotemporal/patologia , Glicina/genética , Masculino , Camundongos , Fenótipo
5.
J Vis Exp ; (173)2021 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-34338673

RESUMO

Before neuronal degeneration, the cause of motor and cognitive deficits in patients with amyotrophic lateral sclerosis (ALS) and/or frontotemporal lobe dementia (FTLD) is dysfunction of communication between neurons and motor neurons and muscle. The underlying process of synaptic transmission involves membrane depolarization-dependent synaptic vesicle fusion and the release of neurotransmitters into the synapse. This process occurs through localized calcium influx into the presynaptic terminals where synaptic vesicles reside. Here, the protocol describes fluorescence-based live-imaging methodologies that reliably report depolarization-mediated synaptic vesicle exocytosis and presynaptic terminal calcium influx dynamics in cultured neurons. Using a styryl dye that is incorporated into synaptic vesicle membranes, the synaptic vesicle release is elucidated. On the other hand, to study calcium entry, Gcamp6m is used, a genetically encoded fluorescent reporter. We employ high potassium chloride-mediated depolarization to mimic neuronal activity. To quantify synaptic vesicle exocytosis unambiguously, we measure the loss of normalized styryl dye fluorescence as a function of time. Under similar stimulation conditions, in the case of calcium influx, Gcamp6m fluorescence increases. Normalization and quantification of this fluorescence change are performed in a similar manner to the styryl dye protocol. These methods can be multiplexed with transfection-based overexpression of fluorescently tagged mutant proteins. These protocols have been extensively used to study synaptic dysfunction in models of FUS-ALS and C9ORF72-ALS, utilizing primary rodent cortical and motor neurons. These protocols easily allow for rapid screening of compounds that may improve neuronal communication. As such, these methods are valuable not only for the study of ALS but for all areas of neurodegenerative and developmental neuroscience research.


Assuntos
Esclerose Lateral Amiotrófica , Exocitose , Humanos , Neurônios Motores , Terminações Pré-Sinápticas , Transmissão Sináptica , Vesículas Sinápticas
6.
Sensors (Basel) ; 21(6)2021 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-33808558

RESUMO

This paper summarises a literature review on the applications of Internet of Things (IoT) with the aim of enhancing building energy use and reducing greenhouse gas emissions (GHGs). A detailed assessment of contemporary practical reviews and works was conducted to understand how different IoT systems and technologies are being developed to increase energy efficiencies in both residential and commercial buildings. Most of the reviewed works were invariably related to the dilemma of efficient heating systems in buildings. Several features of the central components of IoT, namely, the hardware and software needed for building controls, are analysed. Common design factors across the many IoT systems comprise the selection of sensors and actuators and their powering techniques, control strategies for collecting information and activating appliances, monitoring of actual data to forecast prospect energy consumption and communication methods amongst IoT components. Some building energy applications using IoT are provided. It was found that each application presented has the potential for significant energy reduction and user comfort improvement. This is confirmed in two case studies summarised, which report the energy savings resulting from implementing IoT systems. Results revealed that a few elements are user-specific that need to be considered in the decision processes. Last, based on the studies reviewed, a few aspects of prospective research were recommended.

7.
Cutis ; 107(1): 22;39-40, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33651856
9.
HCA Healthc J Med ; 2(6): 397-400, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-37427397

RESUMO

Programmed cell death receptor 1 (PD-1) inhibitors are promising and effective treatments for various cancers. Cutaneous adverse events, such as lichenoid drug eruptions, are well-known common side effects associated with PD-1 inhibitors. Lichenoid drug eruptions associated with PD-1 inhibitors show rapid improvement with high potency topical steroids and do not require cessation of the offending drug. We present the case of an 84-year-old female with progressive pembrolizumab therapy-associated lichenoid eruption that was resistant to several treatments and ultimately required discontinuation of pembrolizumab and treatment with methotrexate to resolve. This report includes histological findings of the pembrolizumab-associated lichenoid eruption.

10.
EMBO Mol Med ; 12(5): e10722, 2020 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-32347002

RESUMO

The most common cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) is an intronic hexanucleotide repeat expansion in the C9orf72 gene. In disease, RNA transcripts containing this expanded region undergo repeat-associated non-AUG translation to produce dipeptide repeat proteins (DPRs), which are detected in brain and spinal cord of patients and are neurotoxic both in vitro and in vivo paradigms. We reveal here a novel pathogenic mechanism for the most abundantly detected DPR in ALS/FTD autopsy tissues, poly-glycine-alanine (GA). Previously, we showed motor dysfunction in a GA mouse model without loss of motor neurons. Here, we demonstrate that mobile GA aggregates are present within neurites, evoke a reduction in synaptic vesicle-associated protein 2 (SV2), and alter Ca2+ influx and synaptic vesicle release. These phenotypes could be corrected by restoring SV2 levels. In GA mice, loss of SV2 was observed without reduction of motor neuron number. Notably, reduction in SV2 was seen in cortical and motor neurons derived from patient induced pluripotent stem cell lines, suggesting synaptic alterations also occur in patients.


Assuntos
Esclerose Lateral Amiotrófica , Demência Frontotemporal , Alanina , Esclerose Lateral Amiotrófica/genética , Animais , Proteína C9orf72/genética , Dipeptídeos , Demência Frontotemporal/genética , Glicina , Humanos , Camundongos , Neurônios Motores
12.
Nat Commun ; 10(1): 5583, 2019 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-31811140

RESUMO

Mutations in fused in sarcoma (FUS) lead to amyotrophic lateral sclerosis (ALS) with varying ages of onset, progression and severity. This suggests that unknown genetic factors contribute to disease pathogenesis. Here we show the identification of muscleblind as a novel modifier of FUS-mediated neurodegeneration in vivo. Muscleblind regulates cytoplasmic mislocalization of mutant FUS and subsequent accumulation in stress granules, dendritic morphology and toxicity in mammalian neuronal and human iPSC-derived neurons. Interestingly, genetic modulation of endogenous muscleblind was sufficient to restore survival motor neuron (SMN) protein localization in neurons expressing pathogenic mutations in FUS, suggesting a potential mode of suppression of FUS toxicity. Upregulation of SMN suppressed FUS toxicity in Drosophila and primary cortical neurons, indicating a link between FUS and SMN. Our data provide in vivo evidence that muscleblind is a dominant modifier of FUS-mediated neurodegeneration by regulating FUS-mediated ALS pathogenesis.


Assuntos
Esclerose Lateral Amiotrófica/metabolismo , Proteínas de Drosophila/metabolismo , Proteínas Nucleares/metabolismo , Proteína FUS de Ligação a RNA/metabolismo , Proteínas do Complexo SMN/metabolismo , Acetiltransferases/genética , Acetiltransferases/metabolismo , Esclerose Lateral Amiotrófica/genética , Animais , Citoplasma/metabolismo , Grânulos Citoplasmáticos/metabolismo , Drosophila/genética , Drosophila/metabolismo , Feminino , Células HEK293 , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Neurônios Motores/metabolismo , Mutação , Fenótipo , Proteína FUS de Ligação a RNA/genética , Proteína FUS de Ligação a RNA/toxicidade , Proteínas do Complexo SMN/genética , Fatores de Transcrição/metabolismo
13.
FASEB J ; 33(12): 13775-13793, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31577916

RESUMO

More than half of spinal cord injury (SCI) cases occur in the cervical region, leading to respiratory dysfunction due to damaged neural circuitry that controls critically important muscles such as the diaphragm. The C3-C5 spinal cord is the location of phrenic motor neurons (PhMNs) that are responsible for diaphragm activation; PhMNs receive bulbospinal excitatory drive predominately from supraspinal neurons of the rostral ventral respiratory group (rVRG). Cervical SCI results in rVRG axon damage, PhMN denervation, and consequent partial-to-complete paralysis of hemidiaphragm. In a rat model of C2 hemisection SCI, we expressed the axon guidance molecule, brain-derived neurotrophic factor (BDNF), selectively at the location of PhMNs (ipsilateral to lesion) to promote directed growth of rVRG axons toward PhMN targets by performing intraspinal injections of adeno-associated virus serotype 2 (AAV2)-BDNF vector. AAV2-BDNF promoted significant functional diaphragm recovery, as assessed by in vivo electromyography. Within the PhMN pool ipsilateral to injury, AAV2-BDNF robustly increased sprouting of both spared contralateral-originating rVRG axons and serotonergic fibers. Furthermore, AAV2-BDNF significantly increased numbers of putative monosynaptic connections between PhMNs and these sprouting rVRG and serotonergic axons. These findings show that targeting circuit plasticity mechanisms involving the enhancement of synaptic inputs from spared axon populations is a powerful strategy for restoring respiratory function post-SCI.-Charsar, B. A., Brinton, M. A., Locke, K., Chen, A. Y., Ghosh, B., Urban, M. W., Komaravolu, S., Krishnamurthy, K., Smit, R., Pasinelli, P., Wright, M. C., Smith, G. M., Lepore, A. C. AAV2-BDNF promotes respiratory axon plasticity and recovery of diaphragm function following spinal cord injury.


Assuntos
Axônios/metabolismo , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Diafragma/metabolismo , Diafragma/fisiologia , Parvovirinae/metabolismo , Recuperação de Função Fisiológica/fisiologia , Traumatismos da Medula Espinal/metabolismo , Animais , Axônios/fisiologia , Dependovirus , Feminino , Neurônios Motores/metabolismo , Neurônios Motores/fisiologia , Ratos , Ratos Sprague-Dawley , Respiração , Medula Espinal/metabolismo , Medula Espinal/fisiologia , Traumatismos da Medula Espinal/fisiopatologia
14.
Int J Womens Health ; 11: 273-285, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31118828

RESUMO

Frontal fibrosing alopecia (FFA) is a primary cicatricial alopecia characterized by loss of follicular stem cells, fibrosis, and a receding frontotemporal hairline, with frequent loss of eyebrows, and less commonly, body hair involvement. Diagnosis is clinical and the disease most often affects postmenopausal women. Treatment is difficult with the goal of disease stabilization rather than hair regrowth due to the scarring nature of FFA. To date, there are no randomized controlled trials evaluating efficacy of treatments. Therefore, much of our knowledge is based on small retrospective studies. In this review, we highlight the various and most current treatment options for FFA, including 5-α-reductase inhibitors, intralesional steroids, hydroxychloroquine, topical steroids, topical calcineurin inhibitors, systemic retinoids, pioglitazone, oral antibiotics, minoxidil, excimer laser, and hair transplantation. Currently, 5-α-reductase inhibitors, intralesional steroids, and hydroxychloroquine have the highest level of evidence for treating FFA, while the remaining therapies have variable results and require further data to draw definitive conclusions.

15.
Dermatol Surg ; 45(7): 950-953, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30741789

RESUMO

BACKGROUND: Sclerotherapy is used to treat varicosities and telangiectases. Glycerin is a sclerosing agent that has been used off-label for years with a favorable adverse effect profile. However, the treatment of facial telangiectases with sclerotherapy is controversial given the potential for necrosis and embolization in relation to the complex vascular anatomy of the face. OBJECTIVE: To determine the safety and efficacy of glycerin sclerotherapy for the treatment of facial telangiectases. MATERIALS AND METHODS: The authors report a series of 8 patients with facial telangiectases treated with glycerin sclerotherapy. Glycerin mixed with lidocaine and epinephrine was used. The telangiectases were measured and identified as targets for treatment. RESULTS: The patients ranged in age from 45 to 88 years. Between 0.5 and 1 mL was used to treat telangiectases of the nose and malar cheek area per session. Five of the patients achieved satisfactory results after 1 treatment, whereas patients with more extensive telangiectases required up to 3 sessions with 4-week intervals between each session. Injection site pain was the only reported adverse effect, and no evidence of necrosis or blindness was observed. CONCLUSION: Glycerin sclerotherapy seems to be a safe and effective modality for the treatment of facial telangiectases.


Assuntos
Dermatoses Faciais/terapia , Glicerol/uso terapêutico , Soluções Esclerosantes/uso terapêutico , Escleroterapia , Telangiectasia/terapia , Idoso , Idoso de 80 Anos ou mais , Anestésicos Locais/uso terapêutico , Estudos de Coortes , Feminino , Humanos , Lidocaína/uso terapêutico , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
16.
Glia ; 66(5): 1016-1033, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29380416

RESUMO

Mutations in fused in sarcoma (FUS) are linked to amyotrophic lateral sclerosis (ALS), a fatal neurodegenerative disease affecting both upper and lower motor neurons. While it is established that astrocytes contribute to the death of motor neurons in ALS, the specific contribution of mutant FUS (mutFUS) through astrocytes has not yet been studied. Here, we used primary astrocytes expressing a N-terminally GFP tagged R521G mutant or wild-type FUS (WTFUS) and show that mutFUS-expressing astrocytes undergo astrogliosis, damage co-cultured motor neurons via activation of an inflammatory response and produce conditioned medium (ACM) that is toxic to motor neurons in isolation. Time lapse imaging shows that motor neuron cultures exposed to mutFUS ACM, but not WTFUS ACM, undergo significant cell loss, which is preceded by progressive degeneration of neurites. We found that Tumor Necrosis Factor-Alpha (TNFα) is secreted into ACM of mutFUS-expressing astrocytes. Accordingly, mutFUS astrocyte-mediated motor neuron toxicity is blocked by targeting soluble TNFα with neutralizing antibodies. We also found that mutant astrocytes trigger changes to motor neuron AMPA receptors (AMPAR) that render them susceptible to excitotoxicity and AMPAR-mediated cell death. Our data provide the first evidence of astrocytic involvement in FUS-ALS, identify TNFα as a mediator of this toxicity, and provide several potential therapeutic targets to protect motor neurons in FUS-linked ALS.


Assuntos
Esclerose Lateral Amiotrófica/genética , Astrócitos/metabolismo , Morte Celular/fisiologia , Neurônios Motores/metabolismo , Proteína FUS de Ligação a RNA/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Esclerose Lateral Amiotrófica/metabolismo , Animais , Astrócitos/patologia , Células Cultivadas , Técnicas de Cocultura , Meios de Cultivo Condicionados , Gliose/patologia , Humanos , Camundongos , Neurônios Motores/patologia , Mutação , NF-kappa B/metabolismo , Neuritos/metabolismo , Neuritos/patologia , Proteína FUS de Ligação a RNA/genética , Ratos , Receptores de AMPA/metabolismo , Medula Espinal/metabolismo , Medula Espinal/patologia
17.
Dermatol Pract Concept ; 7(2): 17-22, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28515987

RESUMO

BACKGROUND: Inadequate dermoscopy training represents a major barrier to proper dermoscopy use. OBJECTIVE: To better understand the status of dermoscopy training in US residency programs. METHODS: A survey was sent to 417 dermatology residents and 118 program directors of dermatology residency programs. RESULTS: Comparing different training times for the same training type, residents with 1-10 hours of dedicated training had similar confidence using dermoscopy in general (p = 1.000) and satisfaction with training (p = .3224) than residents with >10 hours of dedicated training. Comparing similar training times for different training types, residents with 1-10 hours of dedicated training had significantly increased confidence using dermoscopy in general (p = .0105) and satisfaction with training (p = .0066) than residents with 1-10 hours of only bedside training. Lastly, residents with 1-10 hours of dedicated training and >10 hours of dedicated training had significantly increased confidence using dermoscopy in general (p = .0002, p = .2471) and satisfaction with training (p <.0001, p < .0001) than residents with no dermoscopy training at all. CONCLUSIONS: Dermoscopy training in residency should include formal dermoscopy training that is overseen by the program director and is possibly supplemented by outside dermoscopy training.

18.
J Invest Dermatol ; 136(5): e43-e49, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27107377

RESUMO

Assessing the extent of absorption of topical drugs into the various skin layers has been one of the biggest challenges of recent dermatological research. Although skin biopsy samples can be used to directly measure topical drug absorption, biopsies are invasive and not practical for obtaining kinetic data. Common alternative techniques used to assess the bioavailability of topical drugs include in vitro (Franz cell chamber), ex vivo (isolated perfused skin models), and in vivo (vasoconstrictor assay, tape stripping/dermatopharmacokinetics, and microdialysis) techniques. Despite the popularity of these techniques, each technique has its own advantages and disadvantages that limit its use. Consideration of each technique requires that there is a rational linkage to the drug's clinical endpoint and/or site of action. In this article, we review these in vitro, ex vivo, and in vivo techniques, focusing on the basic concepts and the advantages and disadvantages of each technique.


Assuntos
Corticosteroides/farmacologia , Absorção Cutânea/efeitos dos fármacos , Pele/efeitos dos fármacos , Administração Cutânea , Administração Tópica , Disponibilidade Biológica , Sistemas de Liberação de Medicamentos/métodos , Humanos , Técnicas In Vitro , Microdiálise/métodos , Modelos Anatômicos , Pesquisa Qualitativa , Projetos de Pesquisa , Sensibilidade e Especificidade , Pele/metabolismo
19.
Acta Neuropathol ; 131(4): 605-20, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26728149

RESUMO

Amyotrophic lateral sclerosis is characterized by progressive loss of motor neurons in the brain and spinal cord. Mutations in several genes, including FUS, TDP43, Matrin 3, hnRNPA2 and other RNA-binding proteins, have been linked to ALS pathology. Recently, Pur-alpha, a DNA/RNA-binding protein was found to bind to C9orf72 repeat expansions and could possibly play a role in the pathogenesis of ALS. When overexpressed, Pur-alpha mitigates toxicities associated with Fragile X tumor ataxia syndrome (FXTAS) and C9orf72 repeat expansion diseases in Drosophila and mammalian cell culture models. However, the function of Pur-alpha in regulating ALS pathogenesis has not been fully understood. We identified Pur-alpha as a novel component of cytoplasmic stress granules (SGs) in ALS patient cells carrying disease-causing mutations in FUS. When cells were challenged with stress, we observed that Pur-alpha co-localized with mutant FUS in ALS patient cells and became trapped in constitutive SGs. We also found that FUS physically interacted with Pur-alpha in mammalian neuronal cells. Interestingly, shRNA-mediated knock down of endogenous Pur-alpha significantly reduced formation of cytoplasmic stress granules in mammalian cells suggesting that Pur-alpha is essential for the formation of SGs. Furthermore, ectopic expression of Pur-alpha blocked cytoplasmic mislocalization of mutant FUS and strongly suppressed toxicity associated with mutant FUS expression in primary motor neurons. Our data emphasizes the importance of stress granules in ALS pathogenesis and identifies Pur-alpha as a novel regulator of SG dynamics.


Assuntos
Grânulos Citoplasmáticos/metabolismo , Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica/genética , Neurônios Motores/metabolismo , Proteína FUS de Ligação a RNA/metabolismo , Fatores de Transcrição/metabolismo , Esclerose Lateral Amiotrófica/patologia , Animais , Antibacterianos/farmacologia , Arsenitos/farmacologia , Encéfalo/citologia , Proteínas de Transporte/metabolismo , Células Cultivadas , Grânulos Citoplasmáticos/efeitos dos fármacos , DNA Helicases , Proteínas de Ligação a DNA/genética , Doxiciclina/farmacologia , Embrião de Mamíferos , Inibidores Enzimáticos/farmacologia , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas de Ligação a Poli-ADP-Ribose , RNA Helicases , Proteínas com Motivo de Reconhecimento de RNA , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Proteína FUS de Ligação a RNA/genética , Ratos , Ratos Sprague-Dawley , Compostos de Sódio/farmacologia , Fatores de Transcrição/genética
20.
J Cutan Med Surg ; 20(1): 58-66, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26162860

RESUMO

BACKGROUND: Direct-acting antivirals (DAAs) are known to present with additional dermatological events over pegylated-interferon/ribavirin (Peg-IFN/RBV). OBJECTIVE: A systematic review and meta-analysis was conducted to assess the incidence/risk of cutaneous adverse events (AEs) for simeprevir, sofosbuvir, ABT450/r-ombitasvir, dasabuvir, ledipasvir, daclatasvir, and asunaprevir. METHODS: The databases searched included PubMed, Clinicaltrials.gov, and Clinicaloptions.com. Data on telaprevir and boceprevir were obtained from a previous study. RESULTS: The incidences of cutaneous AEs were 34.3% (95% CI 18.4%-54.8%) for the old DAAs + Peg-IFN/RBV, 22.0% (95% CI 17.9%-26.8%) for the new DAAs + Peg-IFN/RBV, 9.8% (95% CI 8.6%-11.2%) for the DAAs + RBV, and 3.8% (95% CI 2.4%-6.1%) for DAAs only. Simeprevir + Peg-IFN/RBV was associated with an increased relative risk over Peg-IFN/RBV; RR = 1.319 (95% CI 1.026-1.697). CONCLUSION: Dermatological events are still an important issue for many of the new DAAs. Appropriate monitoring, management, and patient education are needed to minimize AEs and achieve HCV cure.


Assuntos
Antivirais/efeitos adversos , Hepatite C Crônica/tratamento farmacológico , Dermatopatias/induzido quimicamente , Humanos
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