4,149 research outputs found

    Structure of the Toll/Interleukin-1 Receptor (TIR) Domain of the B-cell Adaptor That Links Phosphoinositide Metabolism with the Negative Regulation of the Toll-like Receptor (TLR) Signalosome

    Get PDF
    Ligand binding to Toll-like receptors (TLRs) results in dimerization of their cytosolic Toll/interleukin-1 receptor (TIR) domains and recruitment of post-receptor signal transducers into a complex signalosome. TLR activation leads to the production of transcription factors and pro-inflammatory molecules and the activation of phosphoinositide 3-kinases (PI3K) in a process that requires the multimodular B-cell adaptor for phosphoinositide 3-kinase (BCAP). BCAP has a sequence previously proposed as a "cryptic" TIR domain. Here, we present the structure of the N-terminal region of human BCAP and show that it possesses a canonical TIR fold. Dimeric BCAP associates with the TIR domains of TLR2/4 and MAL/TIRAP, suggesting that it is recruited to the TLR signalosome by multitypic TIR-TIR interactions. BCAP also interacts with the p85 subunit of PI3K and phospholipase Cγ, enzymes that deplete plasma membrane phosphatidylinositol 4,5-bisphosphate (PIP2), and these interactions provide a molecular explanation for BCAP-mediated down-regulation of inflammatory signaling.This work was supported by a program grant from the UK Medical Research Council (G1000133) and a Wellcome Investigator award (WT100321/z/12/Z to N. J. G.)

    Clinical Reasoning by Veterinary Students in the First-Opinion Setting: Is It Encouraged? Is It Practiced?

    Get PDF
    A mixed-methods study was performed to investigate the perceived importance and efficacy of teaching clinical reasoning (CR) skills among students and faculty in a university first-opinion veterinary practice, as this has not previously been described. Qualitative analysis of interview data, discussing objectives and factors considered important for effective learning and the understanding of CR, was performed alongside quantitative analysis of the Preceptor Thinking-Promotion Scale (PTPS) and the Learner Thinking-Behavior Scale (LTBS) (assessing the level of CR encouraged by clinicians and displayed by students) in peri-consultation discussions. Themes that emerged from analysis of the interviews regarding objectives included the desire to develop data acquisition and the need to improve data manipulation and CR. Themes associated with effective learning were a positive student-centered learning environment and feedback. Type II CR was fairly well described, but recognition of the importance of type I CR was poor among clinicians and students and, in some instances, was deemed to be inappropriate. Although many clinicians and students expressed a desire to develop student CR, there was little evidence of this actually occurring in the interactions analyzed, with low PTPS and LTBS scores achieved. There was also poor understanding of whether effective teaching of CR had occurred, demonstrated by a lack of correlation between LTBS and the interaction score for development of student CR. Further training of clinicians and students of the value of type I CR in first-opinion practice is required, as well as clinician education in how best to support the development of CR in students

    A case of polyarteritis nodosa limited to the right calf muscles, fascia, and skin: a case report

    Get PDF
    <p>Abstract</p> <p>Introduction</p> <p>Limited polyarteritis nodosa is a rare benign disease that usually responds well to systemic corticosteroid treatment. We report a case limited to calf muscles, fascia, and skin treated with local corticosteroid therapy directed to the affected areas by ultrasound guidance.</p> <p>Case presentation</p> <p>A 36-year-old Caucasian woman presented with a 10-month history of progressive right calf pain and swelling, which were unresponsive to treatment with non-steroidal anti-inflammatory drugs and physiotherapy. An examination revealed a swollen tender right calf with indurated overlying skin. Laboratory investigations showed an erythrocyte sedimentation rate of 24 mm/hour and a C-reactive protein of 15 mg/dl. Full blood count, renal profile, and creatinine kinase level were normal. A full autoantibody screen and hepatitis B and C serology results were negative. A chest X-ray was unremarkable. Magnetic resonance imaging of the right leg revealed increased signal intensity in T2-weighted images and this was suggestive of extensive inflammatory changes of the gastrocnemius muscle and, to a lesser extent, the soleus muscle. There were marked inflammatory changes throughout the gastrocnemius muscle and the subcutaneous tissue circumferentially around the right lower leg. A biopsy of affected skin, muscle, and fascia showed histopathological features consistent with polyarteritis nodosa, including small-vessel vasculitis with fibrinoid changes in the vessel wall and intense perivascular and focal mural chronic inflammatory changes. Our patient declined treatment with oral steroids. She received a course of ultrasound-guided injections of steroid (Depo-Medrone, methylprednisolone) in the involved muscle area and commenced maintenance azathioprine with a good response.</p> <p>Conclusions</p> <p>Limited polyarteritis nodosa is rare and affects middle-aged individuals. In most cases, treatment with moderate- to high-dose corticosteroids gives symptomatic relief within one week. Resistant cases require treatment with cytotoxics or intravenous immunoglobulins. This case demonstrates response to local targeted steroid therapy as an alternative to systemic steroids.</p

    The formation of professional identity in medical students: considerations for educators

    Get PDF
    &lt;b&gt;Context&lt;/b&gt; Medical education is about more than acquiring an appropriate level of knowledge and developing relevant skills. To practice medicine students need to develop a professional identity – ways of being and relating in professional contexts.&lt;p&gt;&lt;/p&gt; &lt;b&gt;Objectives&lt;/b&gt; This article conceptualises the processes underlying the formation and maintenance of medical students’ professional identity drawing on concepts from social psychology.&lt;p&gt;&lt;/p&gt; &lt;b&gt;Implications&lt;/b&gt; A multi-dimensional model of identity and identity formation, along with the concepts of identity capital and multiple identities, are presented. The implications for educators are discussed.&lt;p&gt;&lt;/p&gt; &lt;b&gt;Conclusions&lt;/b&gt; Identity formation is mainly social and relational in nature. Educators, and the wider medical society, need to utilise and maximise the opportunities that exist in the various relational settings students experience. Education in its broadest sense is about the transformation of the self into new ways of thinking and relating. Helping students form, and successfully integrate their professional selves into their multiple identities, is a fundamental of medical education

    BAFF, APRIL and BAFFR on the pathogenesis of Immunoglobulin-A vasculitis

    Get PDF
    BAFF, APRIL and BAFF-R are key proteins involved in the development of B-lymphocytes and autoimmunity. Additionally, BAFF, APRIL and BAFFR polymorphisms were associated with immune-mediated conditions, being BAFF GCTGT>A a shared insertion-deletion genetic variant for several autoimmune diseases. Accordingly, we assessed whether BAFF, APRIL and BAFFR represent novel genetic risk factors for Immunoglobulin-A vasculitis (IgAV), a predominantly B-lymphocyte inflammatory condition. BAFF rs374039502, which colocalizes with BAFF GCTGT>A, and two tag variants within APRIL (rs11552708 and rs6608) and BAFFR (rs7290134 and rs77874543) were genotyped in 386 Caucasian IgAV patients and 806 matched healthy controls. No genotypes or alleles differences were observed between IgAV patients and controls when BAFF, APRIL and BAFFR variants were analysed independently. Likewise, no statistically significant differences were found in the genotype and allele frequencies of BAFF, APRIL or BAFFR when IgAV patients were stratified according to the age at disease onset or to the presence/absence of gastrointestinal (GI) or renal manifestations. Similar results were disclosed when APRIL and BAFFR haplotypes were compared between IgAV patients and controls and between IgAV patients stratified according to the clinical characteristics mentioned above. Our results suggest that BAFF, APRIL and BAFFR do not contribute to the genetic network underlying IgAV.Acknowledgements: We are indebted to the patients and healthy controls for their essential collaboration to this study. We also thank the National DNA Bank Repository (Salamanca) for supplying part of the control samples. This study was supported by European Union FEDER funds and `Fondo de Investigaciones Sanitarias´ (grant PI18/00042) from ‘Instituto de Salud Carlos III’ (ISCIII, Health Ministry, Spain). DP-P is a recipient of a Río Hortega programme fellowship from the ISCIII, co-funded by the European Social Fund (ESF, `Investing in your future´) (grant number CM20/00006). SR-M is supported by funds of the RETICS Program (RD16/0012/0009) (ISCIII, co-funded by the European Regional Development Fund (ERDF)). VP-C is supported by a pre-doctoral grant from IDIVAL (PREVAL 18/01). BA-M is a recipient of a `López Albo´ Post-Residency Programme funded by Servicio Cántabro de Salud. LL-G is supported by funds from IDIVAL (INNVAL20/06). OG is staff personnel of Xunta de Galicia (Servizo Galego de Saude (SERGAS)) through a research-staff stabilization contract (ISCIII/SERGAS) and his work is funded by ISCIII and the European Union FEDER fund (grant numbers RD16/0012/0014 (RIER) and PI17/00409). He is beneficiary of project funds from the Research Executive Agency (REA) of the European Union in the framework of MSCA-RISE Action of the H2020 Programme, Project 734899—Olive-Net. RL-M is a recipient of a Miguel Servet type I programme fellowship from the ISCIII, cofunded by ESF (`Investing in your future´) (grant number CP16/00033)

    Oynophagia in patients after dental extraction: surface electromyography study

    Get PDF
    OBJECTIVES: Surface electromyographic (sEMG) studies were performed on 40 adult patients following extraction of lower third and second molars to research the approach and limitations of sEMG evaluation of their odynophagia complaints. METHODS: Parameters evaluated during swallowing and drinking include the timing, number of swallows per 100 cc of water, and range (amplitude) of EMG activity of m. masseter, infrahyoid and submental-submandibular group. The above mentioned variables (mean + standard deviation) were measured for the group of dental patients (n = 40) and control group of healthy adults (n = 40). RESULTS: The duration of swallows and drinking in all tests showed increase in dental patients' group, in which this tendency is statistically significant. There was no statistically significant difference between male and female adults' duration and amplitude of muscle activity during continuous drinking in both groups (p = 0.05). The mean of electric activity (in μV) of m. masseter was significantly lower in the dental patients' group in comparison with control group. The electric activity of submental-submandimular and infrahyoid muscle groups was the same in both groups. CONCLUSION: Surface EMG of swallowing is a simple and reliable noninvasive method for evaluation of odynophagia/dysphagia complaints following dental extraction with low level of discomfort of the examination. The surface EMG studies prove that dysphagia following dental extraction and molar surgery has oral origin, does not affect pharingeal segment and submental-submandibular muscle group. This type of dysphagia has clear EMG signs: increased duration of single swallow, longer drinking time, low range of electric activity of m. masseter, normal range of activity of submental-submandibular muscle group, and the "dry swalow" aftereffect. The data can be used for evaluation of complaints and symptoms, as well as for comparison purposes in pre- and postoperative stages and in EMG monitoring during treatment of post-surgical oral cavity discomfort and dysphagia

    Oral vs. pharyngeal dysphagia: surface electromyography randomized study

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>A clear differential diagnosis between oral and pharyngeal dysphagia remains an unsolved problem. Disorders of the oral cavity are frequently overlooked when dysphagia/odybophagia complaints are assessed. Surface electromyographic (sEMG) studies were performed on randomly assigned patients with oral and pharyngeal pathology to evaluate their dysphagia complaints for the sake of differential diagnosis.</p> <p>Methods</p> <p>Parameters evaluated during swallowing for patients after dental surgery (1: n = 62), oral infections (2: n = 49), acute tonsillitis (3: n = 66) and healthy controls (4: n = 50) included timing and amplitude of sEMG activity of masseter, infrahyoid and submental muscles.</p> <p>Results</p> <p>The duration of swallows and drinking periods was significantly increased in dental patients and was normal in patients with tonsillitis. The electric activity of masseter was significantly lower in Groups 1 and 2 in comparison with the patients with tonsillitis and controls. The submental and infrahyoid activity was normal in dental patients but infrahyoid activity in patients with tonsillitis was high.</p> <p>Conclusion</p> <p>Dysphagia following dental surgery or oral infections does not affect pharynx and submental muscles and has clear sEMG signs: increased duration of a single swallow, longer drinking time, low activity of the masseter, and normal range of submental activity. Patients with tonsillitis present hyperactivity of infrahyoid muscles. These data could be used for evaluation of symptoms when differential dental/ENT diagnosis is needed.</p

    Revised estimates of influenza-associated excess mortality, United States, 1995 through 2005

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Excess mortality due to seasonal influenza is thought to be substantial. However, influenza may often not be recognized as cause of death. Imputation methods are therefore required to assess the public health impact of influenza. The purpose of this study was to obtain estimates of monthly excess mortality due to influenza that are based on an epidemiologically meaningful model.</p> <p>Methods and Results</p> <p>U.S. monthly all-cause mortality, 1995 through 2005, was hierarchically modeled as Poisson variable with a mean that linearly depends both on seasonal covariates and on influenza-certified mortality. It also allowed for overdispersion to account for extra variation that is not captured by the Poisson error. The coefficient associated with influenza-certified mortality was interpreted as ratio of total influenza mortality to influenza-certified mortality. Separate models were fitted for four age categories (<18, 18–49, 50–64, 65+). Bayesian parameter estimation was performed using Markov Chain Monte Carlo methods. For the eleven year study period, a total of 260,814 (95% CI: 201,011–290,556) deaths was attributed to influenza, corresponding to an annual average of 23,710, or 0.91% of all deaths.</p> <p>Conclusion</p> <p>Annual estimates for influenza mortality were highly variable from year to year, but they were systematically lower than previously published estimates. The excellent fit of our model with the data suggest validity of our estimates.</p
    corecore