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51.
Sandeep K. Mallipattu Sylvia J. Horne Vivette D’Agati Goutham Narla Ruijie Liu Michael A. Frohman Kathleen Dickman Edward Y. Chen Avi Ma’ayan Agnieszka B. Bialkowska Amr M. Ghaleb Mandayam O. Nandan Mukesh K. Jain Ilse Daehn Peter Y. Chuang Vincent W. Yang John C. He 《The Journal of clinical investigation》2015,125(3):1347-1361
52.
Stamatis Adamopoulos Jean‐Paul Schmid Paul Dendale Daniel Poerschke Dominique Hansen Athanasios Dritsas Alexandros Kouloubinis Toon Alders Aggeliki Gkouziouta Ilse Reyckers Vasiliki Vartela Nikos Plessas Costas Doulaptsis Hugo Saner Ioannis D. Laoutaris 《European journal of heart failure》2014,16(5):574-582
53.
Patrick Adam Samy Hakroush Ilse Hofmann Sonja Reidenbach Alexander Marx Philipp Ströbel 《Virchows Archiv : an international journal of pathology》2014,465(3):313-320
Due to its profound therapeutic consequences, the distinction between thymoma and T-lymphoblastic lymphoma in needle biopsies is one of the most challenging in mediastinal pathology. One essential diagnostic criterion favouring thymoma is the demonstration of increased numbers of keratin-positive epithelial cells by immunohistochemistry. Loss of keratin expression in neoplastic epithelial cells could lead to detrimental misdiagnoses. We here describe a series of 14 thymic epithelial tumours (11 type B2 and B3 thymomas, 3 thymic carcinomas) with loss of expression of one or more keratins. Cases were analysed for expression of various keratins and desmosomal proteins by immunohistochemistry and immunofluorescence and compared with 45 unselected type B thymomas and 24 thymic carcinomas arranged in a multitissue histological array. All 14 cases showed highly reduced expression of at least one keratin, three cases were completely negative for all keratins studied. Of the 14 cases, 13 showed strong nuclear expression of p63. Expression of desmosomal proteins was preserved, suggesting intact cell contact structures. Loss of expression of broad-spectrum-keratins and K19 was observed in 3 and 5 % of unselected thymomas and in 30 and 60 % of thymic carcinomas. A proportion of keratin-depleted thymomas contained giant cells, reminiscent of thymic nurse cells. Loss of keratin expression in type B2 and B3 thymomas is an important diagnostic pitfall in the differential diagnosis with T-lymphoblastic lymphoma and can be expected in 5 % of cases. A panel of epithelial markers including p63 is warranted to ensure correct diagnosis of keratin-negative mediastinal tumours. 相似文献
54.
Differential role of NK cells against Candida albicans infection in immunocompetent or immunocompromised mice
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Jessica Quintin Jessica Voigt Robbert van der Voort Ilse D. Jacobsen Ineke Verschueren Bernhard Hube Evangelos J. Giamarellos‐Bourboulis Jos W. M. van der Meer Leo A. B. Joosten Oliver Kurzai Mihai G. Netea 《European journal of immunology》2014,44(8):2405-2414
Little is known regarding the role of NK cells during primary and secondary disseminated Candida albicans infection. We assessed the role of NK cells for host defense against candidiasis in immunocompetent, as well as immunodeficient, hosts. Surprisingly, depletion of NK cells in immunocompetent WT mice did not increase susceptibility to systemic candidiasis, suggesting that NK cells are redundant for antifungal defense in otherwise immunocompetent hosts. NK‐cell‐depleted mice were found to be protected as a consequence of attenuation of systemic inflammation. In contrast, the absence of NK cells in T/B/NK‐cell‐deficient NSG (NOD SCID gamma) mice led to an increased susceptibility to both primary and secondary systemic C. albicans infections compared with T/B‐cell‐deficient SCID mice. In conclusion, this study demonstrates that NK cells are an essential and nonredundant component of anti‐C. albicans host defense in immunosuppressed hosts with defective T/B‐lymphocyte immunity, while contributing to hyperinflammation in immunocompetent hosts. The discovery of the importance of NK cells in hosts with severe defects of adaptive immunity might have important consequences for the design of adjunctive immunotherapeutic approaches in systemic C. albicans infections targeting NK‐cell function. 相似文献
55.
Mebis L Eerdekens A Güiza F Princen L Derde S Vanwijngaerden YM Vanhorebeek I Darras VM Van den Berghe G Langouche L 《Endocrinology》2012,153(2):973-984
Both starvation and critical illness are hallmarked by changes in circulating thyroid hormone parameters with typically low T(3) concentrations in the absence of elevated TSH. This constellation is labeled nonthyroidal illness (NTI). Because critical illness is often accompanied by anorexia and a failing gastrointestinal tract, the NTI of critical illness may be confounded by nutrient deficiency. In an experimental study performed in a rabbit model, we investigated the impact of nutritional deficit on the NTI of sustained critical illness. Critically ill rabbits were randomly allocated to parenteral nutrition (moderate dose 270 kcal/d) initiated on the day after injury and continued until d 7 of illness or to infusing a similar volume of dextrose 1.4% (14 kcal/d). With early parenteral nutrition during illness, the decrease in serum T(3) observed with fasting was reversed, whereas the fall in T(4) was not significantly affected. The rise in T(3) with parenteral nutrition paralleled an increase of liver and kidney type-1 and a decrease of liver and kidney type-3 deiodinase activity and an increase in circulating and central leptin. Nuclear staining of constitutive androstane receptor and its downstream expression of sulfotransferases were reduced in fasting ill animals. TRH expression in the hypothalamus was not different in fasted and fed ill rabbits, although circulating TSH levels were higher with feeding. In conclusion, in this rabbit model of sustained critical illness, reduced circulating T(3), but not T(4), levels could be prevented by parenteral nutrition, which may be mediated by leptin and its actions on tissue deiodinase activity. 相似文献
56.
Pancreatic ductal adenocarcinoma (PDAC) has long been considered to arise from pancreatic ducts on the basis of its morphology, the occurrence of dysplasia in putative preneoplastic ductal lesions, and the absence of acinar dysplasia in the pancreas of patients with PDAC. However, evidence gathered through both in vitro studies and--more importantly--genetic mouse models of PDAC shows that ductal-type tumours can arise from acinar cells. These findings raise new important questions related to PDAC pathophysiology and call for in-depth studies of acinar cell differentiation in order to better understand PDAC biology. The authors review these issues and discuss how the novel findings should impact on future work aiming at early diagnosis and improved outcome of patients with PDAC. 相似文献
57.
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59.
El-Galaly TC Mylam KJ Brown P Specht L Christiansen I Munksgaard L Johnsen HE Loft A Bukh A Iyer V Nielsen AL Hutchings M 《Haematologica》2012,97(6):931-936
Background
The value of performing post-therapy routine surveillance imaging in patients with Hodgkin lymphoma is controversial. This study evaluates the utility of positron emission tomography/computed tomography using 2-[18F]fluoro-2-deoxyglucose for this purpose and in situations with suspected lymphoma relapse.Design and Methods
We conducted a multicenter retrospective study. Patients with newly diagnosed Hodgkin lymphoma achieving at least a partial remission on first-line therapy were eligible if they received positron emission tomography/computed tomography surveillance during follow-up. Two types of imaging surveillance were analyzed: “routine” when patients showed no signs of relapse at referral to positron emission tomography/computed tomography, and “clinically indicated” when recurrence was suspected.Results
A total of 211 routine and 88 clinically indicated positron emission tomography/computed tomography studies were performed in 161 patients. In ten of 22 patients with recurrence of Hodgkin lymphoma, routine imaging surveillance was the primary tool for the diagnosis of the relapse. Extranodal disease, interim positron emission tomography-positive lesions and positron emission tomography activity at response evaluation were all associated with a positron emission tomography/computed tomography-diagnosed preclinical relapse. The true positive rates of routine and clinically indicated imaging were 5% and 13%, respectively (P=0.02). The overall positive predictive value and negative predictive value of positron emission tomography/computed tomography were 28% and 100%, respectively. The estimated cost per routine imaging diagnosed relapse was US$ 50,778.Conclusions
Negative positron emission tomography/computed tomography reliably rules out a relapse. The high false positive rate is, however, an important limitation and a confirmatory biopsy is mandatory for the diagnosis of a relapse. With no proven survival benefit for patients with a pre-clinically diagnosed relapse, the high costs and low positive predictive value make positron emission tomography/computed tomography unsuitable for routine surveillance of patients with Hodgkin lymphoma. 相似文献60.
Herrmann H Cerny-Reiterer S Gleixner KV Blatt K Herndlhofer S Rabitsch W Jäger E Mitterbauer-Hohendanner G Streubel B Selzer E Schwarzinger I Sperr WR Valent P 《Haematologica》2012,97(2):219-226