118 research outputs found

    Improved extraction technique for biological fluids

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    Liquid-liquid extraction technique speeds up separation of biological fluids into number of compounds. This eliminates agitation, emulsion formation, centrifugation, mechanical separation of phases, filtration, and other steps that have been used previously. Extraction efficiencies are equal or better than current manual liquid-liquid extraction techniques

    Liquid sample processor

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    Processor is automatic and includes series of extraction tubes packed with fibrous absorbent material of large surface area. When introduced into these tubes, liquid test samples become completely absorbed by packing material as thin film

    Glucocorticoid pharmacogenetics in pediatric idiopathic nephrotic syndrome

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    Idiopathic nephrotic syndrome represents the most common type of primary glomerular disease in children: glucocorticoids (GCs) are the first-line therapy, even if considerable interindividual differences in thepir efficacy and side effects have been reported. Immunosuppressive and anti-inflammatory effects of these drugs are mainly due to the GC-mediated transcription regulation of pro- and anti-inflammatory genes. This mechanism of action is the result of a complex multistep pathway that involves the glucocorticoid receptor and several other proteins, encoded by polymorphic genes. Aim of this review is to highlight the current knowledge on genetic variants that could affect GC response, particularly focusing on children with idiopathic nephrotic syndrome

    Determinants of synaptic integration and heterogeneity in rebound firing explored with data-driven models of deep cerebellar nucleus cells

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    Significant inroads have been made to understand cerebellar cortical processing but neural coding at the output stage of the cerebellum in the deep cerebellar nuclei (DCN) remains poorly understood. The DCN are unlikely to just present a relay nucleus because Purkinje cell inhibition has to be turned into an excitatory output signal, and DCN neurons exhibit complex intrinsic properties. In particular, DCN neurons exhibit a range of rebound spiking properties following hyperpolarizing current injection, raising the question how this could contribute to signal processing in behaving animals. Computer modeling presents an ideal tool to investigate how intrinsic voltage-gated conductances in DCN neurons could generate the heterogeneous firing behavior observed, and what input conditions could result in rebound responses. To enable such an investigation we built a compartmental DCN neuron model with a full dendritic morphology and appropriate active conductances. We generated a good match of our simulations with DCN current clamp data we recorded in acute slices, including the heterogeneity in the rebound responses. We then examined how inhibitory and excitatory synaptic input interacted with these intrinsic conductances to control DCN firing. We found that the output spiking of the model reflected the ongoing balance of excitatory and inhibitory input rates and that changing the level of inhibition performed an additive operation. Rebound firing following strong Purkinje cell input bursts was also possible, but only if the chloride reversal potential was more negative than −70 mV to allow de-inactivation of rebound currents. Fast rebound bursts due to T-type calcium current and slow rebounds due to persistent sodium current could be differentially regulated by synaptic input, and the pattern of these rebounds was further influenced by HCN current. Our findings suggest that active properties of DCN neurons could play a crucial role for signal processing in the cerebellum

    Interactive Responses of a Thalamic Neuron to Formalin Induced Lasting Pain in Behaving Mice

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    Thalamocortical (TC) neurons are known to relay incoming sensory information to the cortex via firing in tonic or burst mode. However, it is still unclear how respective firing modes of a single thalamic relay neuron contribute to pain perception under consciousness. Some studies report that bursting could increase pain in hyperalgesic conditions while others suggest the contrary. However, since previous studies were done under either neuropathic pain conditions or often under anesthesia, the mechanism of thalamic pain modulation under awake conditions is not well understood. We therefore characterized the thalamic firing patterns of behaving mice in response to nociceptive pain induced by inflammation. Our results demonstrated that nociceptive pain responses were positively correlated with tonic firing and negatively correlated with burst firing of individual TC neurons. Furthermore, burst properties such as intra-burst-interval (IntraBI) also turned out to be reliably correlated with the changes of nociceptive pain responses. In addition, brain stimulation experiments revealed that only bursts with specific bursting patterns could significantly abolish behavioral nociceptive responses. The results indicate that specific patterns of bursting activity in thalamocortical relay neurons play a critical role in controlling long-lasting inflammatory pain in awake and behaving mice

    NO2 inhalation induces maturation of pulmonary CD11c+ cells that promote antigenspecific CD4+ T cell polarization

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    <p>Abstract</p> <p>Background</p> <p>Nitrogen dioxide (NO<sub>2</sub>) is an air pollutant associated with poor respiratory health, asthma exacerbation, and an increased likelihood of inhalational allergies. NO<sub>2 </sub>is also produced endogenously in the lung during acute inflammatory responses. NO<sub>2 </sub>can function as an adjuvant, allowing for allergic sensitization to an innocuous inhaled antigen and the generation of an antigen-specific Th2 immune response manifesting in an allergic asthma phenotype. As CD11c<sup>+ </sup>antigen presenting cells are considered critical for naïve T cell activation, we investigated the role of CD11c<sup>+ </sup>cells in NO<sub>2</sub>-promoted allergic sensitization.</p> <p>Methods</p> <p>We systemically depleted CD11c<sup>+ </sup>cells from transgenic mice expressing a simian diphtheria toxin (DT) receptor under of control of the CD11c promoter by administration of DT. Mice were then exposed to 15 ppm NO<sub>2 </sub>followed by aerosolized ovalbumin to promote allergic sensitization to ovalbumin and were studied after subsequent inhaled ovalbumin challenges for manifestation of allergic airway disease. In addition, pulmonary CD11c<sup>+ </sup>cells from wildtype mice were studied after exposure to NO<sub>2 </sub>and ovalbumin for cellular phenotype by flow cytometry and <it>in vitro </it>cytokine production.</p> <p>Results</p> <p>Transient depletion of CD11c<sup>+ </sup>cells during sensitization attenuated airway eosinophilia during allergen challenge and reduced Th2 and Th17 cytokine production. Lung CD11c<sup>+ </sup>cells from wildtype mice exhibited a significant increase in MHCII, CD40, and OX40L expression 2 hours following NO<sub>2 </sub>exposure. By 48 hours, CD11c<sup>+</sup>MHCII<sup>+ </sup>DCs within the mediastinal lymph node (MLN) expressed maturation markers, including CD80, CD86, and OX40L. CD11c<sup>+</sup>CD11b<sup>- </sup>and CD11c<sup>+</sup>CD11b<sup>+ </sup>pulmonary cells exposed to NO<sub>2 </sub><it>in vivo </it>increased uptake of antigen 2 hours post exposure, with increased ova-Alexa 647<sup>+ </sup>CD11c<sup>+</sup>MHCII<sup>+ </sup>DCs present in MLN from NO<sub>2</sub>-exposed mice by 48 hours. Co-cultures of ova-specific CD4<sup>+ </sup>T cells from naïve mice and CD11c<sup>+ </sup>pulmonary cells from NO<sub>2</sub>-exposed mice produced IL-1, IL-12p70, and IL-6 <it>in vitro </it>and augmented antigen-induced IL-5 production.</p> <p>Conclusions</p> <p>CD11c<sup>+ </sup>cells are critical for NO<sub>2</sub>-promoted allergic sensitization. NO<sub>2 </sub>exposure causes pulmonary CD11c<sup>+ </sup>cells to acquire a phenotype capable of increased antigen uptake, migration to the draining lymph node, expression of MHCII and co-stimulatory molecules required to activate naïve T cells, and secretion of polarizing cytokines to shape a Th2/Th17 response.</p

    Rebound Discharge in Deep Cerebellar Nuclear Neurons In Vitro

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    Neurons of the deep cerebellar nuclei (DCN) play a critical role in defining the output of cerebellum in the course of encoding Purkinje cell inhibitory inputs. The earliest work performed with in vitro preparations established that DCN cells have the capacity to translate membrane hyperpolarizations into a rebound increase in firing frequency. The primary means of distinguishing between DCN neurons has been according to cell size and transmitter phenotype, but in some cases, differences in the firing properties of DCN cells maintained in vitro have been reported. In particular, it was shown that large diameter cells in the rat DCN exhibit two phenotypes of rebound discharge in vitro that may eventually help define their functional roles in cerebellar output. A transient burst and weak burst phenotype can be distinguished based on the frequency and pattern of rebound discharge immediately following a hyperpolarizing stimulus. Work to date indicates that the difference in excitability arises from at least the degree of activation of T-type Ca2+ current during the immediate phase of rebound firing and Ca2+-dependent K+ channels that underlie afterhyperpolarizations. Both phenotypes can be detected following stimulation of Purkinje cell inhibitory inputs under conditions that preserve resting membrane potential and natural ionic gradients. In this paper, we review the evidence supporting the existence of different rebound phenotypes in DCN cells and the ion channel expression patterns that underlie their generation

    Physiotherapists' experiences of physiotherapy interventions in scientific physiotherapy publications focusing on interventions for children with cerebral palsy: a qualitative phenomenographic approach

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    Background: Physiotherapy research concerning interventions for children with CP is often focused on collecting evidence of the superiority of particular therapeutic methods or treatment modalities. Articulating and documenting the use of theory, instrumentation and research design and the assumptions underlying physiotherapy research interventions are important. Physiotherapy interventions focusing on children with Cerebral Palsy should, according to the literature, be based on a functional and environmental perspective with task-specific functional activity, motor learning processes and Family-Centred Service i.e. to enhance motor ability and improve capacity so that the child can perform the tasks necessary to participate actively in everyday life. Thus, it is important to coordinate the norms and values of the physiotherapist with those of the family and child. The aim of this study was to describe how physiotherapists' experiences physiotherapy interventions for children with CP in scientific physiotherapy publications written by physiotherapists. Methods: A qualitative phenomenographic approach was used. Twenty-one scientific articles, found in PubMed, strategically chosen according to year of publication (2001-2009), modality, journals and country, were investigated. Results: Three qualitatively different descriptive categories were identified: A: Making it possible a functional-based intervention based on the biopsychosocial health paradigm, and the role of the physiotherapist as collaborative, interacting with the child and family in goal setting, intervention planning and evaluation, B: Making it work an impairment-based intervention built on a mixed health paradigm (biomedical and biopsychosocial), and the role of the physiotherapist as a coach, leading the goal setting, intervention planning and evaluation and instructing family members to carry out physiotherapist directed orders, and; C: Making it normal an impairment-based intervention built on a biomedical health paradigm, and the role of the physiotherapist as an authoritative expert who determine goals, intervention planning and evaluation. Conclusions: Different paradigms of health and disability lead to different approaches to physiotherapy which influence the whole intervention process regarding strategies for the assessment and treatment, all of which influence Family-Centred Service and the child's motor learning strategies. The results may deepen physiotherapists' understanding of how different paradigms of health influence the way in which various physiotherapy approaches in research seek to solve the challenge of CP

    ATP-Dependent Infra-Slow (<0.1 Hz) Oscillations in Thalamic Networks

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    An increasing number of EEG and resting state fMRI studies in both humans and animals indicate that spontaneous low frequency fluctuations in cerebral activity at <0.1 Hz (infra-slow oscillations, ISOs) represent a fundamental component of brain functioning, being known to correlate with faster neuronal ensemble oscillations, regulate behavioural performance and influence seizure susceptibility. Although these oscillations have been commonly indicated to involve the thalamus their basic cellular mechanisms remain poorly understood. Here we show that various nuclei in the dorsal thalamus in vitro can express a robust ISO at ∼0.005–0.1 Hz that is greatly facilitated by activating metabotropic glutamate receptors (mGluRs) and/or Ach receptors (AchRs). This ISO is a neuronal population phenomenon which modulates faster gap junction (GJ)-dependent network oscillations, and can underlie epileptic activity when AchRs or mGluRs are stimulated excessively. In individual thalamocortical neurons the ISO is primarily shaped by rhythmic, long-lasting hyperpolarizing potentials which reflect the activation of A1 receptors, by ATP-derived adenosine, and subsequent opening of Ba2+-sensitive K+ channels. We argue that this ISO has a likely non-neuronal origin and may contribute to shaping ISOs in the intact brain

    Nasal lavage natural killer cell function is suppressed in smokers after live attenuated influenza virus

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    <p>Abstract</p> <p>Background</p> <p>Modified function of immune cells in nasal secretions may play a role in the enhanced susceptibility to respiratory viruses that is seen in smokers. Innate immune cells in nasal secretions have largely been characterized by cellular differentials using morphologic criteria alone, which have successfully identified neutrophils as a significant cell population within nasal lavage fluid (NLF) cells. However, flow cytometry may be a superior method to fully characterize NLF immune cells. We therefore characterized immune cells in NLF by flow cytometry, determined the effects of live attenuated influenza virus (LAIV) on NLF and peripheral blood immune cells, and compared responses in samples obtained from smokers and nonsmokers.</p> <p>Methods</p> <p>In a prospective observational study, we characterized immune cells in NLF of nonsmokers at baseline using flow cytometry and immunohistochemistry. Nonsmokers and smokers were inoculated with LAIV on day 0 and serial nasal lavages were collected on days 1-4 and day 9 post-LAIV. LAIV-induced changes of NLF cells were characterized using flow cytometry. Cell-free NLF was analyzed for immune mediators by bioassay. Peripheral blood natural killer (NK) cells from nonsmokers and smokers at baseline were stimulated <it>in vitro </it>with LAIV followed by flow cytometric and mediator analyses.</p> <p>Results</p> <p>CD45(+)CD56(-)CD16(+) neutrophils and CD45(+)CD56(+) NK cells comprised median 4.62% (range 0.33-14.52) and 23.27% (18.29-33.97), respectively, of non-squamous NLF cells in nonsmokers at baseline. LAIV did not induce changes in total NK cell or neutrophil percentages in either nonsmokers or smokers. Following LAIV inoculation, CD16(+) NK cell percentages and granzyme B levels increased in nonsmokers, and these effects were suppressed in smokers. LAIV inoculation enhanced expression of activating receptor NKG2D and chemokine receptor CXCR3 on peripheral blood NK cells from both nonsmokers and smokers <it>in vitro </it>but did not induce changes in CD16(+) NK cells or granzyme B activity in either group.</p> <p>Conclusions</p> <p>These data are the first to identify NK cells as a major immune cell type in the NLF cell population and demonstrate that mucosal NK cell cytotoxic function is suppressed in smokers following LAIV. Altered NK cell function in smokers suggests a potential mechanism that may enhance susceptibility to respiratory viruses.</p
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