Nerve Agent Hydrolysis Activity Designed into a Human Drug Metabolism Enzyme

Organophosphorus (OP) nerve agents are potent suicide inhibitors of the essential neurotransmitter-regulating enzyme acetylcholinesterase. Due to their acute toxicity, there is significant interest in developing effective countermeasures to OP poisoning. Here we impart nerve agent hydrolysis activity into the human drug metabolism enzyme carboxylesterase 1. Using crystal structures of the target enzyme in complex with nerve agent as a guide, a pair of histidine and glutamic acid residues were designed proximal to the enzyme's native catalytic triad. The resultant variant protein demonstrated significantly increased rates of reactivation following exposure to sarin, soman, and cyclosarin. Importantly, the addition of these residues did not alter the high affinity binding of nerve agents to this protein. Thus, using two amino acid substitutions, a novel enzyme was created that efficiently converted a group of hemisubstrates, compounds that can start but not complete a reaction cycle, into bona fide substrates. Such approaches may lead to novel countermeasures for nerve agent poisoning

Fascin 2b Is a Component of Stereocilia that Lengthens Actin-Based Protrusions

Stereocilia are actin-filled protrusions that permit mechanotransduction in the internal ear. To identify proteins that organize the cytoskeleton of stereocilia, we scrutinized the hair-cell transcriptome of zebrafish. One promising candidate encodes fascin 2b, a filamentous actin-bundling protein found in retinal photoreceptors. Immunolabeling of zebrafish hair cells and the use of transgenic zebrafish that expressed fascin 2b fused to green fluorescent protein demonstrated that fascin 2b localized to stereocilia specifically. When filamentous actin and recombinant fusion protein containing fascin 2b were combined in vitro to determine their dissociation constant, a Kd≈0.37 µM was observed. Electron microscopy showed that fascin 2b-actin filament complexes formed parallel actin bundles in vitro. We demonstrated that expression of fascin 2b or espin, another actin-bundling protein, in COS-7 cells induced the formation of long filopodia. Coexpression showed synergism between these proteins through the formation of extra-long protrusions. Using phosphomutant fascin 2b proteins, which mimicked either a phosphorylated or a nonphosphorylated state, in COS-7 cells and in transgenic hair cells, we showed that both formation of long filopodia and localization of fascin 2b to stereocilia were dependent on serine 38. Overexpression of wild-type fascin 2b in hair cells was correlated with increased stereociliary length relative to controls. These findings indicate that fascin 2b plays a key role in shaping stereocilia

Serum Biomarkers of Disease Activity in Longitudinal Assessment of Patients with ANCA-Associated Vasculitis

OBJECTIVE: Improved biomarkers of current disease activity and prediction of relapse are needed in antineutrophil cytoplasmic antibody–associated vasculitis (AAV). For clinical relevance, biomarkers must perform well longitudinally in patients on treatment and in patients with nonsevere flares. METHODS: Twenty‐two proteins were measured in 347 serum samples from 74 patients with AAV enrolled in a clinical trial. Samples were collected at Month 6 after remission induction, then every 3 months until Month 18, or at the time of flare. Associations of protein concentrations with concurrent disease activity and with future flare were analyzed using mixed‐effects models, Cox proportional hazards models, and conditional logistic regression. RESULTS: Forty‐two patients had flares during the 12‐month follow‐up period, and 32 remained in remission. Twenty‐two patients had severe flares. Six experimental markers (CXCL13, IL‐6, IL‐8, IL‐15, IL‐18BP, and matrix metalloproteinase‐3 [MMP‐3]) and ESR were associated with disease activity using all three methods (P < 0.05, with P < 0.01 in at least one method). A rise in IL‐8, IL‐15, or IL‐18BP was associated temporally with flare. Combining C‐reactive protein (CRP), IL‐18BP, neutrophil gelatinase‐associated lipocalin (NGAL), and sIL‐2Rα improved association with active AAV. CXCL13 and MMP‐3 were increased during treatment with prednisone, independent of disease activity. Marker concentrations during remission were not predictive of future flare. CONCLUSION: Serum biomarkers of inflammation and tissue damage and repair have been previously shown to be strongly associated with severe active AAV were less strongly associated with active AAV in a longitudinal study that included mild flares and varying treatment. Markers rising contemporaneously with flare or with an improved association in combination merit further study

Risk of Conversion to Dementia in a Mild Behavioral Impairment Group Compared to a Psychiatric Group and to a Mild Cognitive Impairment Group

Background: There is insufficient available information on behavioral changes in the absence of cognitive impairment as factors increasing the risk of conversion to dementia. Objective: To observe and analyze patients with mild behavioral impairment (MBI), mild cognitive impairment (MCI), and a psychiatry group (PG) to compare the risk of progression to dementia. Methods: From 677 initially assessed =60-year-old patients, a series of 348 patients was studied for a five-year period until censoring or conversion to dementia: 96 with MBI, 87 with MCI, and 165 with general psychiatry disorders, including 4 subgroups: Anxiety, Depression, Psychosis and Others. All patients were assessed with clinical, psychiatric, neurological, neuropsychological, and neuroimaging studies. Results: From 348 patients, 126 evolved to dementia (36.2%). Conversion was significantly higher in MBI (71.5%), followed by the MCI-MBI overlap (59.6%) and MCI (37.8%) groups, compared to PG (13.9%) (Log-rank p < 0.001). MCI patients mostly converted to Alzheimer's dementia, while MBI converted to frontotemporal dementia and Lewy body dementia. Patients in PG converted to Lewy body dementia and frontotemporal dementia. Conclusion: Conversion to dementia is significantly higher in patients with neuropsychiatric symptoms. The MBI concept generates a new milestone in the refining of diagnosis of neurodegenerative diseases and the possibility of creating neuropsychiatric profiles. Its earlier identification will allow new possibilities for therapeutic intervention.Fil: Taragano, Fernando Emilio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. CEMIC-CONICET. Centro de Educaciones Médicas e Investigaciones Clínicas "Norberto Quirno". CEMIC-CONICET; ArgentinaFil: Allegri, Ricardo Francisco. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. CEMIC-CONICET. Centro de Educaciones Médicas e Investigaciones Clínicas "Norberto Quirno". CEMIC-CONICET; ArgentinaFil: Heisecke Peralta, Silvina Lidia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. CEMIC-CONICET. Centro de Educaciones Médicas e Investigaciones Clínicas "Norberto Quirno". CEMIC-CONICET; ArgentinaFil: Martelli, María I.. Centro de Educación Médica e Investigaciones Clínicas "Norberto Quirno"; ArgentinaFil: Feldman, Mónica L.. Centro de Educación Médica e Investigaciones Clínicas "Norberto Quirno"; ArgentinaFil: Sánchez, Viviana. Centro de Educación Médica e Investigaciones Clínicas "Norberto Quirno"; ArgentinaFil: García, Virginia A.. Centro de Educación Médica e Investigaciones Clínicas "Norberto Quirno"; ArgentinaFil: Tufro, Graciela. Centro de Educación Médica e Investigaciones Clínicas "Norberto Quirno"; ArgentinaFil: Castro, Diego M.. Centro de Educación Médica e Investigaciones Clínicas "Norberto Quirno"; ArgentinaFil: Leguizamón, Patricio Perez. Centro de Educación Médica e Investigaciones Clínicas "Norberto Quirno"; ArgentinaFil: Guelar, Verónica. Centro de Educación Médica e Investigaciones Clínicas "Norberto Quirno"; ArgentinaFil: Ruotolo, Eva. Centro de Educación Médica e Investigaciones Clínicas "Norberto Quirno"; ArgentinaFil: Zegarra, Cecilia. Centro de Educación Médica e Investigaciones Clínicas "Norberto Quirno"; ArgentinaFil: Dillon, Carol. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. CEMIC-CONICET. Centro de Educaciones Médicas e Investigaciones Clínicas "Norberto Quirno". CEMIC-CONICET; Argentin

Association of Pulmonary Hemorrhage, Positive Proteinase 3, and Urinary Red Blood Cell Casts With Venous Thromboembolism in Antineutrophil Cytoplasmic Antibody-Associated Vasculitis

Objective To assess the frequency of venous thromboembolism (VTE) events in the Rituximab in Antineutrophil Cytoplasmic Antibody (ANCA)-Associated Vasculitis (RAVE) trial and identify novel potential risk factors. Methods VTE events in 197 patients enrolled in the RAVE trial were analyzed. Baseline demographic and clinical characteristics were recorded, and univariate and multivariate analyses were performed to identify factors associated with VTE in ANCA-associated vasculitis (AAV). Results VTE occurred in 16 patients (8.1%) with an overall average time to event of 1.5 months (range 1.0-2.75). In univariate analyses with calculation of hazard ratios (HRs) and 95% confidence intervals (95% CIs), heart involvement (HR 17.408 [95% CI 2.247-134.842]; P = 0.006), positive proteinase 3 (PR3)-ANCA (HR 7.731 [95% CI 1.021-58.545]; P = 0.048), pulmonary hemorrhage (HR 3.889 [95% CI 1.448-10.448]; P = 0.008), and the presence of red blood cell casts (HR 15.617 [95% CI 3.491-69.854]; P <0.001) were associated with the onset of VTE. In multivariate models adjusted for age and sex, the significant associations between VTE events and heart involvement (HR 21.836 [95% CI 2.566-185.805]; P = 0.005), PR3-ANCA (HR 9.12 [95% CI 1.158-71.839]; P = 0.036), pulmonary hemorrhage (HR 3.91 [95% CI 1.453-10.522]; P = 0.007), and urinary red blood cell casts (HR 16.455 [95% CI 3.607-75.075]; P <0.001) remained. Conclusion Patients diagnosed as having AAV with pulmonary hemorrhage, positive PR3-ANCA, heart involvement, and the presence of red blood cell casts are at an increased risk to develop VTE. Further studies are needed to confirm and expand these findings and to explore the mechanisms of hypercoagulability in these patients with the aim of informing potential targets for therapeutic intervention

Prognostic and predictive factors in recurrent and/or metastatic head and neck squamous cell carcinoma : A review of the literature

The pattern of clinical behaviour and response to treatment of recurrent and/or metastatic head and neck squamous cell carcinoma is heterogeneous. Treatment strategies that can be employed vary from potentially curative salvage surgery and re-irradiation to palliative systemic therapies and best supportive care. The advent of new therapeutic options, in terms of more sophisticated surgical approaches and techniques, highly conformal and precise radiation techniques and immunotherapy may offer improved control of disease and longer survival. Moreover, the epidemiological changes during the last decades, including the increase of human papilloma virus-related oropharyngeal primary tumors, are also reflected in the recurrent and metastatic setting. In this complex context the identification of predictive and prognostic factors is urgently needed to tailor treatment, to increase its efficacy, and to avoid unnecessary toxicities. A better knowledge of prognosis may also help the patients and caregivers in decision making on the optimal choice of care. The purpose of our review is to highlight the current evidence and shortcomings in this field.Peer reviewe

Asthma outcomes: Exacerbations

The goals of asthma treatment include preventing recurrent exacerbations. Yet there is no consensus about the terminology for describing or defining “exacerbation,” or about how to characterize an episode’s severity