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Characterization of cutaneous and articular sensory neurons
Background: A wide range of stimuli can activate sensory neurons and neurons innervating specific tissues often have distinct properties. Here we used retrograde tracing to identify sensory neurons innervating the hind paw skin (cutaneous) and ankle/knee joints (articular), and combined immunohistochemistry and electrophysiology analysis to determine the neurochemical phenotype of cutaneous and articular neurons, as well as their electrical and chemical excitability.
Results: Immunohistochemistry analysis using RetroBeads as a retrograde tracer confirmed previous data that cutaneous and articular neurons are a mixture of myelinated and unmyelinated neurons, and the majority of both populations are peptidergic. In whole-cell patch-clamp recordings from cultured dorsal root ganglion neurons, voltage-gated inward currents and action potential parameters were largely similar between articular and cutaneous neurons, although cutaneous neuron action potentials had a longer half-peak duration. An assessment of chemical sensitivity showed that all neurons responded to a pH 5.0 solution, but that acid-sensing ion channel (ASIC) currents, determined by inhibition with the non-selective ASIC antagonist benzamil, were of a greater magnitude in cutaneous compared to articular neurons. 40 – 50% of cutaneous and articular neurons responded to capsaicin, cinnamaldehyde and menthol, indicating similar expression levels of TRPV1, TRPA1 and TRPM8 respectively. By contrast, significantly more articular neurons responded to ATP than cutaneous neurons.
Conclusion: This work makes a detailed characterization of cutaneous and articular sensory neurons, and highlights the importance of making recordings from identified neuronal populations: sensory neurons innervating different tissues have subtly different properties, possibly reflecting different functions.ISS was funded by an Erasmus for Graduate Students grant from the University of Coimbra. ZMAH and experiments were funded by an Arthritis Research Project Grant (Grant Reference 20930) to ESS. JDB was funded by a Corpus Christi College Study and Travel Grant. EStJS was funded by an Early Career Research Grant from the International Association for the Study of Pain. Thanks to Christoforos Tsantoulas for assistance with immunohistochemistry and members of the Smith lab for their technical assistance and help in preparing the manuscript.This is the final version of the article. It first appeared from SAGE via http://dx.doi.org/10.1177/174480691663638
BABIES WITH BRAIN DAMAGE WHO CAN NOT SWALLOW Surgical management
Background: Neonates with severe neurological impairment are often unable to swallow, necessitating gastrostomy for feeding. Because of the risk of developing severe reflux, this procedure is often associated with fundoplication. Objective: To assess the safety and efficacy of gastrostomy and Nissen fundoplication in 22 neonates with swallowing difficulties due to serious neurological impairment. Method: All children underwent an initial period of nasogastric feeding and after informed consent underwent gastrostomy and Nissen fundoplication. Results: There were no significant intraoperative complications. There were two cases of postoperative periostomy leakage. Of the 22 neonates 16 were alive four months after surgery. Six neonates died of complications due to underlying disease. Conclusion: We concluded that gastrostomy and Nissen fundoplication are safe procedures and help parents give a better care to these children.663B64164
TRANSPORTE PÚBLICO
INTRODUÇÃOO projeto será através de um relatório, com um artigo em anexo, que será entregue ao SETERB – Serviço Autônomo Municipal de Trânsito e Transportes de Blumenau, sendo esse projeto criado devido à crise do transporte público da cidade de Blumenau, SC, vivenciada entre 2015 e 2016.O objetivo é levar ao órgão sugestões e ideias recolhidas de outras cidades e em consulta popular no grupo do Facebook Coletivo Blumenau, para o contrato oficial do transporte público na cidade, sendo o documento publicado em outros meios, como o site do IFC – Campus Blumenau e no Coletivo Blumenau. MATERIAIS E MÉTODOSReunindo informações de sistemas de transporte público de diversos lugares do Brasil e em consulta popular em redes sociais, no caso foi utilizado o Facebook, foi desenvolvido este trabalho.Algumas sugestões foram desenvolvidas pelos autores do projeto, como o item IBRTS do trabalho, que é algo que não existe atualmente, mas pode ser dito como a união de vários aspectos dos SITs (Sistemas Integrados de Transporte) e dos sistemas BRT (Bus Rapid Transit) em uma única modalidade de sistemas de transporte público.Outras sugestões foram de sugestão popular, vindos do grupo Coletivo Blumenau e vindos de pesquisa de sistemas de transporte público de outras cidades.Ainda serão recolhidas sugestões durante a realização do evento, dos dias 27 a 28 de Outubro, através de um espaço no feedback que o público poderá preencher após a apresentação do projeto. RESULTADOS E DISCUSSÃOO resultado até o momento foi a reunião de várias sugestões e ideias para o relatório que, já que o mesmo ainda estava em fase de montagem quando foi escrito este documento no dia 03 de Outubro de 2016. Os resultados possíveis desse relatório é a aceitação de vários itens que serão apresentados no mesmo, o que leve ao melhoramento do transporte público da cidade alvo do projeto, além de lançar uma nova modalidade de sistema de transporte público.Entre as sugestões incluídas estão diversos itens, sendo que ainda podem ser adicionados mais itens após a realização do evento, mas entre alguns deles estão novas linhas, criação de plataformas que auxiliem a fiscalização do sistema de transporte público, uma nova modalidade de transporte público, o IBRTS, podendo ser chamado também de Mini-BRT e integração entre modais.Ainda há a possibilidade de se fazer outro documento para o SETERB, se caso surgir outras sugestões, que forem entregues após a entrega do relatório ao órgão citado e se for realmente viável para se realizar a elaboração de outro documento a nível do construído.Os documentos serão não só entregues ao SETERB, mas serão publicados em outros meios, como o site do campus e em sites especializados sobre o tema (exemplo: o site Ônibus Brasil) além do grupo do Facebook, Coletivo Blumenau, onde foi inclusive realizada a pesquisa popular de sugestões para o relatório. CONCLUSÃOO projeto obteve resultados no nível de pesquisa de sugestões e ideias para o relatório, mas se pode concluir também que o mesmo tem grande potencial para conseguir resultados concretos, a partir de aceitação de sugestões apresentadas no documento, para melhorar o transporte coletivo da cidade de Blumenau, ainda havendo a possibilidade de se lançar outro documento que irá ter o mesmo destino do relatório e artigo entregues ao SETERB e publicados em outros meios de comunicação, porém ainda no início do novo contrato oficial do transporte coletivo de Blumenau, sendo os documentos podendo servir de referência para cidades que ainda estão desenvolvendo um sistema de transporte coletivo e que procuram tê-lo com qualidade e com mínimo de problemas que possam ocorrer ao sistema dessas cidades, como o caso de Timbó, SC e de outras cidades Brasil afora.
Implementation of a Toffoli Gate with Superconducting Circuits
The quantum Toffoli gate allows universal reversible classical computation.
It is also an important primitive in many quantum circuits and quantum error
correction schemes. Here we demonstrate the realization of a Toffoli gate with
three superconducting transmon qubits coupled to a microwave resonator. By
exploiting the third energy level of the transmon qubit, the number of
elementary gates needed for the implementation of the Toffoli gate, as well as
the total gate time can be reduced significantly in comparison to theoretical
proposals using two-level systems only. We characterize the performance of the
gate by full process tomography and Monte Carlo process certification. The gate
fidelity is found to be %.Comment: 4 pages, 5figure
Conditional ablation of the choroideremia gene causes age-related changes in mouse retinal pigment epithelium.
The retinal pigment epithelium (RPE) is a pigmented monolayer of cells lying between the photoreceptors and a layer of fenestrated capillaries, the choriocapillaris. Choroideremia (CHM) is an X-linked progressive degeneration of these three layers caused by the loss of function of Rab Escort protein-1 (REP1). REP1 is involved in the prenylation of Rab proteins, key regulators of membrane trafficking. To study the pathological consequences of chronic disruption of membrane traffic in the RPE we used a cell type-specific knock-out mouse model of the disease, where the Chm/Rep1 gene is deleted only in pigmented cells (Chm(Flox), Tyr-Cre+). Transmission electron microscopy (TEM) was used to quantitate the melanosome distribution in the RPE and immunofluorescent staining of rhodopsin was used to quantitate phagocytosed rod outer segments in retinal sections. The ultrastructure of the RPE and Bruch's membrane at different ages was characterised by TEM to analyse age-related changes occurring as a result of defects in membrane traffic pathways. Chm/Rep1 gene knockout in RPE cells resulted in reduced numbers of melanosomes in the apical processes and delayed phagosome degradation. In addition, the RPE accumulated pathological changes at 5-6 months of age similar to those observed in 2-year old controls. These included the intracellular accumulation of lipofuscin-containing deposits, disorganised basal infoldings and the extracellular accumulation of basal laminar and basal linear deposits. The phenotype of the Chm(Flox), Tyr-Cre+ mice suggests that loss of the Chm/Rep1 gene causes premature accumulation of features of aging in the RPE. Furthermore, the striking similarities between the present observations and some of the phenotypes reported in age-related macular degeneration (AMD) suggest that membrane traffic defects may contribute to the pathogenesis of AMD
Recommended from our members
Characterization of cutaneous and articular sensory neurons.
BACKGROUND: A wide range of stimuli can activate sensory neurons and neurons innervating specific tissues often have distinct properties. Here, we used retrograde tracing to identify sensory neurons innervating the hind paw skin (cutaneous) and ankle/knee joints (articular), and combined immunohistochemistry and electrophysiology analysis to determine the neurochemical phenotype of cutaneous and articular neurons, as well as their electrical and chemical excitability. RESULTS: Immunohistochemistry analysis using RetroBeads as a retrograde tracer confirmed previous data that cutaneous and articular neurons are a mixture of myelinated and unmyelinated neurons, and the majority of both populations are peptidergic. In whole-cell patch-clamp recordings from cultured dorsal root ganglion neurons, voltage-gated inward currents and action potential parameters were largely similar between articular and cutaneous neurons, although cutaneous neuron action potentials had a longer half-peak duration (HPD). An assessment of chemical sensitivity showed that all neurons responded to a pH 5.0 solution, but that acid-sensing ion channel (ASIC) currents, determined by inhibition with the nonselective acid-sensing ion channel antagonist benzamil, were of a greater magnitude in cutaneous compared to articular neurons. Forty to fifty percent of cutaneous and articular neurons responded to capsaicin, cinnamaldehyde, and menthol, indicating similar expression levels of transient receptor potential vanilloid 1 (TRPV1), transient receptor potential ankyrin 1 (TRPA1), and transient receptor potential melastatin 8 (TRPM8), respectively. By contrast, significantly more articular neurons responded to ATP than cutaneous neurons. CONCLUSION: This work makes a detailed characterization of cutaneous and articular sensory neurons and highlights the importance of making recordings from identified neuronal populations: sensory neurons innervating different tissues have subtly different properties, possibly reflecting different functions.ISS was funded by an Erasmus for Graduate Students grant from the University of Coimbra. ZMAH and experiments were funded by an Arthritis Research Project Grant (Grant Reference 20930) to ESS. JDB was funded by a Corpus Christi College Study and Travel Grant. EStJS was funded by an Early Career Research Grant from the International Association for the Study of Pain. Thanks to Christoforos Tsantoulas for assistance with immunohistochemistry and members of the Smith lab for their technical assistance and help in preparing the manuscript.This is the final version of the article. It first appeared from SAGE via http://dx.doi.org/10.1177/174480691663638
Determination of the antimutagenicity of an aqueous extract of Rhizophora mangle L. (Rhizophoraceae), using in vivo and in vitro test systems
An aqueous extract of Rhizophora mangle L. bark is used as raw material in pottery making in the State of Espirito Santo, Brazil. This extract presents large quantities of tannins, compounds possessing antioxidant properties. Tannin antioxidant activity, as a plant chemical defense mechanism in the process of stabilizing free radicals, has been an incentive to studies on anti-mutagenicity. The present work aimed to evaluate possible antimutagenic activity of a R. mangle aqueous extract, using the Allium cepa test-system and micronuclear (MN) assay with blockage of cytokinesis in Chinese hamster ovary cells (CHO-K1). The Allium cepa test-system indicated antimutagenic activity against the damage induced by the mutagenic agent methyl methanesulfonate. A reduction in both MN cell frequency and chromosome breaks occurred in both the pre and post-treatment protocols. The MN testing of CHO-K1 cells revealed anti-mutagenic activity of the R. mangle extract against methyl methanesulfonate and doxorubicin in pre, simultaneous and post-treatment protocols. These results suggest the presence of phyto-constituents in the extract presenting demutagenic and bio-antimutagenic activities. Since the chemical constitution of Rhizophora mangle species presents elevated tannin content, it is highly probable that these compounds are the antimutagenic promoters themselves
Selectively Cross-Linked Tetra-PEG Hydrogels Provide Control over Mechanical Strength with Minimal Impact on Diffusivity.
Synthetic hydrogels formed from poly(ethylene glycol) (PEG) are widely used to study how cells interact with their extracellular matrix. These in vivo-like 3D environments provide a basis for tissue engineering and cell therapies but also for research into fundamental biological questions and disease modeling. The physical properties of PEG hydrogels can be modulated to provide mechanical cues to encapsulated cells; however, the impact of changing hydrogel stiffness on the diffusivity of solutes to and from encapsulated cells has received only limited attention. This is particularly true in selectively cross-linked "tetra-PEG" hydrogels, whose design limits network inhomogeneities. Here, we used a combination of theoretical calculations, predictive modeling, and experimental measurements of hydrogel swelling, rheological behavior, and diffusion kinetics to characterize tetra-PEG hydrogels' permissiveness to the diffusion of molecules of biologically relevant size as we changed polymer concentration, and thus hydrogel mechanical strength. Our models predict that hydrogel mesh size has little effect on the diffusivity of model molecules and instead predicts that diffusion rates are more highly dependent on solute size. Indeed, our model predicts that changes in hydrogel mesh size only begin to have a non-negligible impact on the concentration of a solute that diffuses out of hydrogels for the smallest mesh sizes and largest diffusing solutes. Experimental measurements characterizing the diffusion of fluorescein isothiocyanate (FITC)-labeled dextran molecules of known size aligned well with modeling predictions and suggest that doubling the polymer concentration from 2.5% (w/v) to 5% produces stiffer gels with faster gelling kinetics without affecting the diffusivity of solutes of biologically relevant size but that 10% hydrogels can slow their diffusion. Our findings provide confidence that the stiffness of tetra-PEG hydrogels can be modulated over a physiological range without significantly impacting the transport rates of solutes to and from encapsulated cells
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