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Avipoxviruses are responsible for decreased egg production, reduced growth and increased mortality in poultry. The disease has re-emerged as a new threat to poultry farmers as a number of outbreaks have been reported worldwide. Several workers have characterized the field strains of fowlpox virus and found incorporation of reticuloendotheliosis (REV) provirus in their genome. Here, the authors present the cases of poxvirus infection in three avian species viz., poultry, turkey and pigeon in north eastern India and found REV genes within the genome of poxvirus isolated from poultry and turkey. The presence of REV in the flocks of the region need to be further investigated as it reflects the emerging threats to the poultry industry at large and poultry rearing in the region in particular.  相似文献   
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Statins have shown antineoplastic properties in preclinical studies with breast cancer cells. They inhibit the enzyme “HMG CoA reductase” and the expression of this enzyme in cancer cells has been implicated as a favorable prognostic factor in patients with breast cancer. After a search of MEDLINE and Embase from inception through November 2015, 817 abstracts were reviewed to identify studies that described an association between statin use and outcomes in breast cancer. A total of 14 studies which included 75,684 women were identified. In a meta‐analysis of 10 studies, statin use was associated with improved recurrence‐free survival (RFS; HR 0.64; 95% CI 0.53–0.79, I2 = 44%). Furthermore, this RFS benefit appeared to be confined to use of lipophilic statins (HR 0.72; 95% CI 0.59–0.89) as hydrophilic statin use was not associated with improvement in RFS (HR 0.80; 95% CI 0.44–1.46). Statin users similarly showed improved overall survival in a meta‐analysis with substantial heterogeneity (8 studies, HR 0.66; 95% CI 0.44–0.99, I2 = 89%). Statin users also had improved cancer‐specific survival, although this relationship was measured with less precision (six studies, HR 0.70; 95% CI 0.46–1.06, I2 = 86%). In conclusion, breast cancer patients who use statins, or specifically, lipophilic statins show improved recurrence‐free survival. Statin users also had improved overall survival and cancer‐specific survival. These findings should be assessed in a prospective randomized cohort and the choice of statin, dose and biomarkers that may predict the efficacy of these drugs should be identified.  相似文献   
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In colloidal systems, the interplay between the short range attraction and long-range repulsion can lead to a low density associated state consisting of clusters of individual particles. Recently, such an equilibrium cluster phase was also reported for concentrated solutions of lysozyme at low ionic strength and close to the physiological pH. Stradner et al. [(2004) Equilibrium cluster formation in concentrated protein solutions and colloids. Nature 432:492-495] found that the position of the low-angle interference peak in small-angle x-ray and neutron scattering (SAXS and SANS) patterns from lysozyme solutions was essentially independent of the protein concentration and attributed these unexpected results to the presence of equilibrium clusters. This work prompted a series of experimental and theoretical investigations, but also revealed some inconsistencies. We have repeated these experiments following the protein preparation protocols of Stradner et al. using several batches of lysozyme and exploring a broad range of concentrations, temperature and other conditions. Our measurements were done in multiple experimental sessions at three different high-resolution SAXS and SANS instruments. The low-ionic-strength lysozyme solutions displayed a clear shift in peak positions with concentration, incompatible with the presence of the cluster phase but consistent with the system of repulsively interacting individual lysozyme molecules. Within the decoupling approximation, the experimental data can be fitted using an effective interparticle interaction potential involving short-range attraction and long-range repulsion.  相似文献   
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Inhalational drugs often suffer from low pulmonary deposition due to their micronized size. Aim of present study was development and evaluation of a novel submicronic L-arginine respiratory fluid formulation for treatment of cardiopulmonary complications associated with chronic obstructive pulmonary disorder (COPD). Objectives were (a) to develop and characterize submicronic L-arginine respiratory fluid formulation, (b) pre-clinical safety/toxicity study in 2-animal species, (c) in vitro and in vivo evaluation in terms of respiratory fraction, and (d) clinical study to assess safety/efficacy in healthy volunteers/COPD patients. Formulation was optimized on the basis of particle size of aerosolized medication with particle size in the range of 400–500 nm. Anderson cascade impaction (ACI) studies were performed to validate the advantage in terms of respirable fraction, which indicated a high respirable fraction (51.61 ± 3.28) for the developed formulation. In vivo pulmonary deposition pattern of optimized formulation was studied using gamma scintigraphy in human volunteers using 99mTc-arginine as radiotracer. It clearly demonstrated a significant pulmonary deposition of the submicronic formulation in various lung compartments. Efficacy of the developed formulation was further assessed in COPD patients (n = 15) by evaluating its effect on various cardiopulmonary parameters (spirometry, pulse-oxymetry, echocardiography and 6-min walk test). A marked improvement was seen in patients after inhalation of submicronic arginine in terms of their cardiopulmonary status. Results suggest that submicronic arginine respiratory fluid has the potential to be developed into an attractive therapeutic option for treating COPD associated cardiopulmonary complications.  相似文献   
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BACKGROUNDMEK inhibitors have limited activity in biliary tract cancers (BTCs) as monotherapy but are hypothesized to enhance responses to programmed death ligand 1 (PD-L1) inhibition.METHODSThis open-label phase II study randomized patients with BTC to atezolizumab (anti–PD-L1) as monotherapy or in combination with cobimetinib (MEK inhibitor). Eligible patients had unresectable BTC with 1 to 2 lines of prior therapy in the metastatic setting, measurable disease, and Eastern Cooperative Oncology Group (ECOG) performance status less than or equal to 1. The primary endpoint was progression-free survival (PFS).RESULTSSeventy-seven patients were randomized and received study therapy. The trial met its primary endpoint, with a median PFS of 3.65 months in the combination arm versus 1.87 months in the monotherapy arm (HR 0.58, 90% CI 0.35–0.93, 1-tail P = 0.027). One patient in the combination arm (3.3%) and 1 patient in the monotherapy arm (2.8%) had a partial response. Combination therapy was associated with more rash, gastrointestinal events, CPK elevations, and thrombocytopenia. Exploratory analysis of tumor biopsies revealed enhanced expression of antigen processing and presentation genes and an increase in CD8/FoxP3 ratios with combination treatment. Patients with higher baseline or lower fold changes in expression of certain inhibitory ligands (LAG3, BTLA, VISTA) on circulating T cells had evidence of greater clinical benefit from the combination.CONCLUSIONThe combination of atezolizumab plus cobimetinib prolonged PFS as compared with atezolizumab monotherapy, but the low response rate in both arms highlights the immune-resistant nature of BTCs.TRIAL REGISTRATIONClinicalTrials.gov NCT03201458.FUNDINGNational Cancer Institute (NCI) Experimental Therapeutics Clinical Trials Network (ETCTN); F. Hoffmann-La Roche, Ltd.; NCI, NIH (R01 CA228414-01 and UM1CA186691); NCI’s Specialized Program of Research Excellence (SPORE) in Gastrointestinal Cancers (P50 CA062924); NIH Center Core Grant (P30 CA006973); and the Passano Foundation.  相似文献   
109.
Red cell exchange (RCE) is a common procedure in adults with sickle cell disease (SCD). Implantable dual lumen Vortex (DLV) ports can be used for RCE in patients with poor peripheral venous access. We performed a retrospective cohort study of RCE procedures performed in adults with SCD. The main objective of the study was to compare the inlet speed, duration of procedures and rate of complications performed through DLV ports to those performed through temporary central venous and peripheral catheters. Twenty‐nine adults with SCD underwent a total of 318 RCE procedures. Twenty adults had DLV ports placed and 218 procedures were performed using DLV ports. Mean length of follow‐up after DLV port placement was 397 ± 263 days. Six DLV ports were removed due to infection and 1 for malfunction after a mean of 171 ± 120 days. Compared to temporary central venous and peripheral catheters, DLV port procedures had a greater rate of procedural complications, a longer duration, and a lower inlet speed (all P < 0.01). When accounting for the maximum allowable inlet speed to avoid citrate toxicity, 40% of DLV port procedures were greater than 10% below maximum speed, compared to 7 and 14% of procedures performed through temporary central venous and peripheral catheters (P < 0.0001). In conclusion, DLV ports can be used for RCE in adults with SCD, albeit with more procedural complications and longer duration. The smaller internal diameter and longer catheter of DLV ports compared to temporary central venous catheters likely accounts for the differences noted. J. Clin. Apheresis 30:353–358, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   
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