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31.
Induction of the interleukin-12 (IL-12) cytokine family comprising IL-12, IL-23, IL-27, and IL-12p40 by intracellular pathogens is required for orchestration of cell-mediated immune responses. Macrophages (MΦ) have been shown to be a source of IL-12 following TLR4-dependent activation by Salmonella (S.). In this study another antigen-presenting cell type, the conventional dendritic cell (cDC), was analyzed and its cytokine responses compared with those of MΦ. We generated bone marrow-derived conventional dendritic cells (BMDC) and macrophages (BMMΦ) by incubating murine bone marrow cells with supernatants containing granulocyte/macrophage colony-stimulating factor (GM-CSF) or macrophage colony-stimulating factor (M-CSF), respectively. Stimulation of BMDC and BMMΦ with S. enterica serovar Enteritidis (SE) or LPS resulted in the release of IL-12 and IL-23 by BMDC but not by BMMΦ. Furthermore, BMDC secreted approx. 20-fold more IL-12p40 and IL-27p28 than BMMΦ. However, BMDC and BMMΦ produced similar levels of IL-10. Using BMDC originating from wild-type (wt), TLR2def and TLR4def mice, we show that in BMDC the induction of IL-12, IL-23, and IL-27p28 by SE is dependent on TLR4, whereas low-level production of p40 is also mediated by pattern recognition receptors (PRR) other than TLR4. Interestingly, LPS- and SE-provoked responses of BMDC were remarkably similar indicating that LPS is the primary danger molecule of SE. Taken together, our results point to cDC rather than MΦ as the major producers of the IL-12 family members during in vitro infection with SE. The mechanisms of recognition of SE, however, appear to be the same for cDC and MΦ  相似文献   
32.
We detected 3 genotypes of highly pathogenic avian influenza A(H5N8) virus in France during winter 2016–17. Genotype A viruses caused dramatic economic losses in the domestic duck farm industry in southwestern France. Our phylogenetic analysis suggests that genotype A viruses formed 5 distinct geographic clusters in southwestern France. In some clusters, local secondary transmission might have been started by a single introduction. The intensity of the viral spread seems to correspond to the density of duck holdings in each production area. To avoid the introduction of disease into an unaffected area, it is crucial that authorities limit the movements of potentially infected birds.  相似文献   
33.
The Gleason grading system, proposed by Dr. Donald F. Gleason in 1966, is one of the most important prognostic factors in men with prostate cancer (PCa). At consensus conferences held in 2005 and 2014, organized by the International Society of Urological Pathology (ISUP), the system was modified to reflect the current diagnostic and therapeutic approaches. In particular, in the 2014 Conference, it was recognized that there were weaknesses with the original and the 2005 ISUP modified Gleason systems. Based on the results of a research conducted by Prof. JI Epstein and his group, a new grading system was proposed by the ISUP in order to address some of such deficiencies: i.e., the five distinct Grade Groups (GGs). Since 2014, results of studies have been published by different groups and societies, including the Genitourinary Pathology Society (GUPS), giving additional support to the prognostic role of the architectural Gleason patterns and, in particular, of the GGs. A revised GG system, taking into account the percentage of Gleason pattern (GP) 4, cribriform and intraductal carcinoma, tertiary GP 5, and reactive stroma grade, has shown to have some advantages, however not ready for adoption in the current practice. The aim of this contribution was to review the major updates and recommendations regarding the GPs and GSs, as well as the GGs, trying to give an answer to the following questions: “How has the grade group system been used in the routine?” and “will the Gleason scoring system be replace by the grade groups?” We also discussed the potential implementation in the future of molecular pathology and artificial intelligence in grading to further define risk groups in patients with PCa.  相似文献   
34.
ObjectiveTo validate a Russian-language version of the World Health Organization’s Alcohol Use Disorders Identification Test (AUDIT).MethodsWe invited 2173 patients from 21 rural and urban primary health-care centres in nine Russian regions to participate in the study (143 declined and eight were excluded). In a standardized interview, patients who had consumed alcohol in the past 12 months provided information on their sociodemographic characteristics and completed the Russian AUDIT, the Kessler Psychological Distress Scale and the Composite International Diagnostic Interview to identify problem drinking and alcohol use disorders. We assessed the feasibility of administering the test, its internal consistency and its ability to predict hazardous drinking and alcohol use disorders in primary health care in the Russian Federation.FindingsOf the 2022 patients included in the study, 1497 were current drinkers with Russian AUDIT scores. The test was internally consistent with good psychometric properties (Cronbach’s α : 0.842) and accurately predicted alcohol use disorders and other outcomes (area under the curve > 75%). A three-item short form of the test correlated well with the full instrument and had similar predictive power (area under the curve > 80%). We determined sex-specific thresholds for all outcomes, as non-specific thresholds resulted in few women being identified.ConclusionWith the validated Russian AUDIT, there is no longer a barrier to introducing screening and brief interventions into primary health care in the Russian Federation to supplement successful alcohol control policies.  相似文献   
35.
Quality of Life Research - As people around the world are facing the Covid-19 outbreak, their perception of oral health problems could be changed. This study aimed to evaluate the immediate effects...  相似文献   
36.
We present a modeling framework designed for patient-specific computational hemodynamics to be performed in the context of large-scale studies. The framework takes advantage of the integration of image processing, geometric analysis and mesh generation techniques, with an accent on full automation and high-level interaction. Image segmentation is performed using implicit deformable models taking advantage of a novel approach for selective initialization of vascular branches, as well as of a strategy for the segmentation of small vessels. A robust definition of centerlines provides objective geometric criteria for the automation of surface editing and mesh generation. The framework is available as part of an open-source effort, the Vascular Modeling Toolkit, a first step towards the sharing of tools and data which will be necessary for computational hemodynamics to play a role in evidence-based medicine.  相似文献   
37.
Assembly of targeting complexes driven by a single-chain antibody   总被引:2,自引:0,他引:2  
Rapid development in design and production of recombinant antibodies and antibody fragments specific for cell surface markers opens new opportunities for targeted delivery of therapeutic or imaging agents. However, the progress in this field is slowed by inactivation of many antibodies by chemical conjugation of payloads and by lack of internalization of complexes formed on the cell surface. Here, we describe conversion of a non-internalizing single chain Fv (scFv) antibody P4G7 specific for vascular endothelial growth factor receptor 2 (VEGFR-2) into a targeting protein (Hu-P4G7) for assembly of a novel type of targeting complexes. Hu-P4G7 contains an N-terminal "docking" Hu-tag, a 15-aa fragment of human RNase I, capable of high affinity binding of S-protein fragment of human RNase I or bovine RNase A. Purified Hu-P4G7 and complexes of Hu-P4G7 with S-protein bind both soluble and full-length cellular VEGFR-2. To assemble targeted DNA delivery complexes, S-protein modified with a DNA condensing agent was "docked" to Hu-P4G7, and then loaded with luciferase plasmid DNA. As expected for a non-internalizing targeting protein, Hu-P4G7-based complexes did not deliver DNA in VEGFR-2 expressing cells. However, in the presence of vascular endothelial growth factor (VEGF), these complexes selectively delivered DNA into the cells overexpressing VEGFR-2 suggesting that even a non-internalizing scFv antibody can be used for targeted intracellular drug delivery.  相似文献   
38.
The spin-echo procedure is the basic technique in a magnetic resonance (MR) study (the magnetization vector is flipped by 90° onto the ortogonal plane to the main magnetic field). Very soon after the MR procedure was developed, it was pointed out how important it is to achieve the needed contrast with shorter repetition times (TRs) to reduce the imaging time. Recently, fast imaging techniques have been introduced (partial flip angles, short TRs, and the lack of 180° radiofrequency pulses to refocus the spins are their main characteristics; the spins are refocused by the application of a gradient reversal technique). These techniques are particularly needed in pediatric neuroradiology, where the examination time must be as short as possible. At present, partial flip-angle techniques are almost completely replacing the conventional spin-echo procedure, but the variations in flip angle could result in a change in contrast. For these reasons, conventional spin-echo techniques may still be useful in a routine MR study.Presented at the 11th Meeting of the European Society for Paediatric Neurosurgery, Naples 1988  相似文献   
39.
Summary N-pentyl-sparsomycin (PSm) is a lipophilic analogue of sparsomycin (Sm), which is a well known inhibitor of protein synthesis. This compound was selected for preclinical pharmacokinetic studies because of its high in vitro and in vivo antitumor activity. In this study in which the drug was evaluated in beagle dogs under anaesthesia, the drug concentrations in plasma, urine and bile samples were determined using high performance liquid chromatography (HPLC). Plasma protein binding was approximately 54%. The mean t1/2 was 0.2 hours (12 minutes) and t1/2 was 0.75 ± 0.1 hours (45 ± 6 minutes). During continuous infusions up to 5.25 hours, the steady state was reached in 3 out of 6 experiments, suggesting that in some cases the real t1/2 was longer than measured. PSm was actively reabsorbed from the renal tubuli. This process was saturable at the higher doses. Tubular reabsorption played only a minor role in pharmacokinetics as most of the drug (67%) was eliminated by the non-renal clearance. The non-renal clearance was saturable at higher doses of PSm and was the reason for non-linearity of pharmacokinetics.  相似文献   
40.
European Journal of Clinical Microbiology & Infectious Diseases - The aim of this study is to evaluate the chlorhexidine gluconate (CHG) susceptibility in both planktonic cells and biofilm of...  相似文献   
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