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Sasan R. Fereidouni Timm C. Harder Anja Globig Elke Starick 《Influenza and other respiratory viruses》2014,8(6):613-616
Background
Mallard ducks and other waterfowl represent the most important reservoirs of low pathogenic avian influenza viruses (LPAIV). In addition, mallards are the most abundant duck species in Eurasia that migrate over long distances. Despite extended wild bird monitoring studies over the past decade in many Eurasian countries and investigating hundreds of thousands of wild bird samples, no mallard duck was found to be positive for avian influenza virus of subtype H16 in faecal, cloacal or oropharyngeal samples. Just three cases of H16 infections in Anseriformes species were described worldwide. In contrast, H16 viruses have been repeatedly isolated from birds of the Laridae family.Objective
Here, we tested the hypothesis that mallards are less permissive to infection with H16 viruses.Methods
Groups of mallard ducks of different age were inoculated via the oculo-nasal-oral route with different infectious doses of an H16N3 AIV.Results
The ducks did not show any clinical symptoms, and no virus shedding was evident from cloacal and respiratory routes after experimental infection as shown by negative RT-qPCR results. In addition, all serum samples taken on days 8, 21 and 24 post-inoculation were negative by competitive NP-ELISA.Conclusions
This study provided evidence that mallards are resistant to infection with H16N3 LPAIV. 相似文献24.
Trends in incidence,tumour sites and tumour stages of oral and pharyngeal cancer in Northern Germany
Hertrampf K Wiltfang J Katalinic A Timm O Wenz HJ 《Journal of cancer research and clinical oncology》2012,138(3):431-437
Purpose
Oral and pharyngeal cancer is the seventh leading tumour in Europe. In Germany, more than 10,000 new cancer cases are diagnosed each year. This population-based project evaluated the available data to develop a more detailed epidemiological profile of oral and pharyngeal cancer. 相似文献25.
Martin Schecklmann Michael Landgrebe Timm B. Poeppl Peter Kreuzer Peter Männer Jörg Marienhagen David S. Wack Tobias Kleinjung Göran Hajak Berthold Langguth 《Human brain mapping》2013,34(1):233-240
Cerebral 18F‐deoxyglucose positron emission tomography (FDG‐PET) has shown altered auditory pathway activity in tinnitus. However, the corresponding studies involved only small samples and analyses were restricted to the auditory cortex in most studies. Evidence is growing that also limbic, frontal, and parietal areas are involved in the pathophysiology of chronic tinnitus. These regions are considered to mediate perceptual, attentional, and emotional processes. Thus, the aim of the present study was the systematic evaluation of metabolic brain activity in a large sample of tinnitus patients. Ninety one patients with chronic tinnitus underwent FDG‐PET. The effects of tinnitus severity (assessed by a tinnitus questionnaire score), duration and laterality were evaluated with statistical parametric mapping (SPM) in whole brain analyses. In addition, region of interest analyses were performed for primary auditory areas. Tinnitus duration correlated positively with brain metabolism in right inferior frontal, right ventro‐medial prefrontal, and right posterior cingulate cortex. Tinnitus distress correlated positively with activation of left and right posterior inferior temporal gyrus as well as left and right posterior parahippocampal–hippocampal interface. Region of interest analysis demonstrated an overactivation of left in contrast to right Heschl's gyrus independently from tinnitus laterality and anatomical hemispheric differences. Tinnitus duration and distress were associated with areas involved in attentional and emotional processing. This is in line with recent findings indicating the relevance of higher order areas in the pathophysiology of tinnitus. Earlier results of asymmetric activation of the auditory cortices in tinnitus were confirmed, i.e., left‐sided overactivation was found independently from tinnitus laterality. Hum Brain Mapp, 2013. © 2011 Wiley Periodicals, Inc. 相似文献
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Timm Heinbokel Abdallah Elkhal Guangxiang Liu Karoline Edtinger Stefan G. Tullius 《Transplantation reviews (Orlando, Fla.)》2013,27(3):65-75
Increasing numbers of elderly transplant recipients and a growing demand for organs from older donors impose pressing challenges on transplantation medicine. Continuous and complex modifications of the immune system in parallel to aging have a major impact on transplant outcome and organ quality. Both, altered alloimmune responses and increased immunogenicity of organs present risk factors for inferior patient and graft survival. Moreover, a growing body of knowledge on age-dependent modifications of allorecognition and alloimmune responses may require age-adapted immunosuppression and organ allocation.Here, we summarize relevant aspects of immunosenescence and their possible clinical impact on organ transplantation. 相似文献
27.
Kesting MR Mueller C Wagenpfeil S Stoeckelhuber M Steiner T Bauer F Teichmann J Baumann CM Barthel LC Satanovskij RM Mücke T Schulte M Schütz K Wolff KD Rohleder NH 《The British journal of oral & maxillofacial surgery》2012,50(5):447-453
Antimicrobial peptides (AMP) defend epithelial surfaces against pathological micro-organisms. We know of no comparison of their expression between the oral mucosa and extraoral epithelium, but knowledge of differences in their quantities is of interest, possibly as a starting point for new treatments. Expression of AMP human beta-defensin (hBD)-1/-2/-3 and psoriasin in the oral mucosa and extraoral epithelium of the head and neck were measured by real-time polymerase chain reaction (RT-PCR) (n=14), immunohistochemistry (n=6), and western blot (n=8). RT-PCR showed that all the genes investigated were expressed significantly more in the oral mucosa than in the skin (hBD-1: p=0.002; hBD-2: p=0.006; hBD-3: p=0.035; psoriasin: p=0.02). Immunohistochemistry and western blot showed differential concentrations of proteins: hBD-2 (p=0.021) and hBD-3 (p=0.043) were pronounced in the oral mucosa, whereas psoriasin was raised in the extraoral skin (p=0.021). There was no difference in protein concentrations for hBD-1 (p=0.08). The observed differences in the expression of AMP may be important for new treatments such as topical application of AMP derivatives. 相似文献
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Vikas Prasad Nikolaus Tiling Timm Denecke Winfried Brenner Ursula Plöckinger 《European journal of nuclear medicine and molecular imaging》2016,43(11):2014-2020
Purpose
Neuroendocrine tumours of the pancreas (pNET) are observed in 8 – 17 % of patients with von Hippel-Lindau disease (vHLD), and 11 – 20 % of these patients develop metastatic disease. MRI and CT have a very high resolution; however, their sensitivity and specificity for the detection of pNET amongst cystic lesions in the pancreas of vHLD patients are generally considered insufficient. In contrast, 68Ga-DOTATOC PET/CT demonstrates a high sensitivity for the diagnosis and staging of neuroendocrine tumours. In this study we investigated the potential role of 68Ga-DOTATOC PET/CT in screening of patients with vHLD.Method
68Ga-DOTATOC PET/three-phase contrast-enhanced CT was performed according to guidelines in all consecutive vHLD patients between January 2012 and November 2015. All patients underwent additional MRI imaging of the abdomen, spine, and head. Chromogranin A (CgA) was determined at the time of the PET/CT examination. A lesion seen on 68Ga-DOTATOC PET in the pancreas was defined as positive if the uptake was visually higher than in the surrounding tissues. Lesions were quantified using maximum SUV.Results
Overall, 20 patients (8 men, 12 women; mean age 44.7?±?11.1 years) were prospectively examined. Genetically, 12 patients had type 1 vHLD and 8 had type 2 vHLD. 68Ga-DOTATOC PET/CT detected more pNET than morphological imaging (CT or MRI): 11 patients (55 %; 8 type 1, 3 type 2) vs. 9 patients (45 %; 6 type 1, 3 type 2). The concentration of CgA was mildly elevated in 2 of 11 patients with pNET. The mean SUVmax of the pancreatic lesions was 18.9?±?21.9 (range 5.0 – 65.6). Four patients (36.4 %) had multiple pNETs. The mean size of the lesions on CT and/or MRI was 10.4?±?8.3 mm (range 4 – 38 mm), and 41.1 % were larger than 10 mm. In addition, somatostatin receptor-positive cerebellar and spinal haemangioblastomas were detected in three patients (SUVmax 2.1 – 10.1). One patient presented with a solitary somatostatin receptor-positive lymph node metastasis. pNETs were observed more frequently in vHLD type 1 than type 2 (66.7 % vs. 37.5 %, p?=?0.089). None of the patients showed progressive disease during follow-up.Conclusion
In this study, 68Ga-DOTATOC PET detected pNETs in a higher proportion of patients with vHLD than found in previous studies with 111In-octreoscan, the imaging method recommended by the NCCN. We therefore suggest 68Ga-DOTATOC PET/CT as the more sensible screening tool.30.
High efficacy of sofosbuvir/velpatasvir and impact of baseline resistance‐associated substitutions in hepatitis C genotype 3 infection 下载免费PDF全文