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Poorly differentiated neuroendocrine carcinomas (PDNECs) of the gastroenteropancreatic system (GEP) are a heterogeneous group of aggressive malignancies with a high propensity for distant metastases and an ominous prognosis. They have traditionally been divided into small and large cell subtypes on morphological grounds. However, histological diagnosis needs to be supported by immunohistochemistry to avoid possible misdiagnoses either with the more frequent poorly differentiated adenocarcinomas and squamous cell carcinomas or with lymphomas and mesenchymal neoplasms. Although it is well known that GEP PDNECs are associated with a poor prognosis, data from some published studies seem to suggest that there is a fraction of patients with PDNECs who have better survival than expected. GEP PDNECs are currently classified according to the criteria proposed in the 2010 WHO classification. They are simply called neuroendocrine carcinomas (NECs) and are defined by mitotic count >20?×?10 HPF and/or Ki-67 labeling index >20 %. However, a few recent papers have indicated that some NECs, as defined by the 2010 WHO scheme, do not show a poorly differentiated morphology as expected. This category seems to show a better prognosis and, especially, does not respond to cisplatin-based chemotherapy, which represents the goal standard therapeutic approach to high-grade PDNECs. In the present review, the main morphological, immunohistochemical, and prognostic features will be discussed as well as the opportunity to introduce a new category characterized by well to moderately differentiated morphology associated with high proliferation (mitotic count >20?×?10 HPF and/or Ki-67 index >20 %). 相似文献
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Sputum Cytokine Levels in Patients with Pulmonary Tuberculosis as Early Markers of Mycobacterial Clearance 下载免费PDF全文
Rodrigo Ribeiro-Rodrigues Tatiana Resende Co John L. Johnson Fabiola Ribeiro Moises Palaci Ricardo T. S Ethel L. Maciel Fausto E. Pereira Lima Valderio Dettoni Zahra Toossi W. Henry Boom Reynaldo Dietze Jerrold J. Ellner Christina S. Hirsch 《Clinical and Vaccine Immunology : CVI》2002,9(4):818-823
Sputum and serum from patients with active pulmonary tuberculosis (TB), healthy purified protein derivative-positive adults, and patients with bacterial pneumonia were collected to simultaneously assess local immunity in the lungs and peripheral blood. To determine whether cytokine profiles in sputum from TB patients and control subjects were a reflection of its cellular composition, cytospin slides were prepared in parallel and assessed for the presence of relative proportions of epithelial cells, neutrophils, macrophages, and T cells. Gamma interferon (IFN-γ) in sputum from TB patients was markedly elevated over levels for both control groups. With anti-TB therapy, IFN-γ levels in sputum from TB patients decreased rapidly and by week 4 of treatment were comparable to those in sputum from controls. Further, IFN-γ levels in sputum closely followed mycobacterial clearance. Although detected at fourfold-lower levels, IFN-γ immunoreactivities in serum followed kinetics in sputum. TNF-α, interleukin 8 (IL-8) and IL-6 also were readily detected in sputum from TB patients at baseline and responded to anti-TB therapy. In contrast to IFN-γ, however, TNF-α and IL-8 levels also were elevated in sputum from pneumonia controls. These data indicate that sputum cytokines correlate with disease activity during active TB of the lung and may serve as potential early markers for sputum conversion and response to anti-TB therapy. 相似文献
106.
Bcl-2 expression inhibits liver carcinogenesis and delays the development of proliferating foci 总被引:2,自引:0,他引:2 下载免费PDF全文
Pierce RH Vail ME Ralph L Campbell JS Fausto N 《The American journal of pathology》2002,160(5):1555-1560
Tumor development is thought to require both increased proliferation and inhibition of apoptosis. However, the relationship between cell replication and cell death in liver tumorigenesis is complex because both proliferation and apoptosis increase during hepatocarcinogenesis. To investigate the effect of the anti-apoptotic gene Bcl-2 in liver carcinogenesis, we established a line of double transgenic mice that express transforming growth factor-alpha (TGF-alpha), a liver mitogen, and Bcl-2. Double transgenic mice, TGF-alpha and Bcl-2 single transgenics, and wild type received an injection of diethylnitrosamine at 15 days of age. This alkylating agent induces liver carcinogenesis and its effect is greatly enhanced by TGF-alpha. We report that Bcl-2 expression inhibited diethylnitrosamine-induced liver carcinogenesis and counteracted the enhancing effect of TGF-alpha. Bcl-2 delayed the growth of proliferative foci at the early stages of carcinogenesis and inhibited cell proliferation in these foci. The effect of Bcl-2 on liver carcinogenesis is consistent with its reported ability to interfere with cell replication. The data demonstrate that the expression of an anti-apoptotic gene during liver carcinogenesis causes a delay rather than an increase in tumorigenesis. 相似文献
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Tognarini I Sorace S Zonefrati R Galli G Gozzini A Carbonell Sala S Thyrion GD Carossino AM Tanini A Mavilia C Azzari C Sbaiz F Facchini A Capanna R Brandi ML 《Biomaterials》2008,29(7):809-824
Long-term stability of arthroplasty prosthesis depends on the integration between the bone tissue and the implanted biomaterials, which requires the contribution of osteoblastic precursors and their continuous differentiation into the osteoblastic phenotype. Classically, these interactions are tested in vitro using mesenchymal stem cells (MSCs) isolated and ex vivo expanded from bone marrow aspirates. Human adipose tissue-derived stromal cells (AMSCs) may be a more convenient source of MSCs, according to their abundance and accessibility, but no data are available on their in vitro interactions with hard biomaterials. The aim of this work is to compare the osteogenic potential of human AMSCs and bone marrow-derived MSCs (BMMSCs) and to evaluate their response to Ti6Al4V alloy in terms of adhesion, proliferation and differentiation features, using the human osteosarcoma cell line SaOS-2 for comparison. The overall results showed that AMSCs have the same ability to produce bone matrix as BMMSCs and that Ti6Al4V surfaces exhibit an osteoinductive action on AMSCs, promoting their differentiation into functional osteoblasts and increasing bone formation. In conclusion, adipose tissue is a promising autologous source of osteoblastic cells with important clinical implications for bone tissue engineering. 相似文献
109.
Eddie Luidy Imada Diego Strianese Deepak P. Edward Rawan alThaqib Antionette Price Antje Arnold Hailah Al-Hussain Luigi Marchionni Fausto J. Rodriguez 《Brain pathology (Zurich, Switzerland)》2022,32(1):e13007
Although most commonly benign, neurofibromas (NFs) can have devastating functional and cosmetic effects in addition to the possibility of malignant transformation. Orbitofacial NFs, in particular, may cause progressive, disfiguring tumors of the lid, brow, temple, face, and orbit, and clinical evidence suggests that they may have increased local aggressiveness compared to NFs developing at other sites. The purpose of this study was to identify biological differences between orbitofacial NFs and those occurring at other anatomic sites. We performed RNA-sequencing in orbitofacial (n = 10) and non-orbitofacial (n = 9) NFs. Differential gene expression analysis demonstrated that a variety of gene sets including genes involved in cell proliferation, interferon, and immune-related pathways were enriched in orbitofacial NF. Comparisons with publicly available databases of various Schwann cell tumors and malignant peripheral nerve sheath tumor (MPNST) revealed a significant overlap of differentially expressed genes between orbitofacial versus non-orbitofacial NF and plexiform NF versus MPNST. In summary, we identified gene expression differences between orbitofacial NF and NFs occurring at other locations. Further investigation may be warranted, given that orbitofacial NF are notoriously difficult to treat and associated with disproportionate morbidity. 相似文献
110.
Fontani G Lodi L Felici A Corradeschi F Lupo C 《European journal of applied physiology》2004,92(4-5):452-461
The differences in attentional style among subjects of different ages and the influence of emotionality on the attentional components were studied for a limited experimental period. Variation in the hormonal data and its relation to behavioural parameters were also evaluated. The subjects enrolled in the study were divided into four age groups (A 18–29, B 30–45, C 46–59, D 60–77 years). The attentional tests involved different types of attention: alert, go/no-go, divided attention and working memory. Emotionality was assessed on the basis of skin conductance, heart rate and frontalis muscle tone. Testosterone (T), free testosterone (fT), non-specifically bound testosterone (NST), sex hormone binding globulin (sHBG), oestradiol, cortisol and adrenocorticotrophic hormone were determined in the plasma. The data were analysed to identify endocrine and behavioural differences related to sex and age. The results showed an influence of age on reaction time (RT) and RT variability. This was particularly evident for groups C and D with respect to A in the simple (alert) and complex RT tests (go/no-go and working memory). Divided attention, with the highest RT, showed a clear distinction between group A and the other groups. The difference in frontalis electromyography (EMG) (test vs control) increased with age, while the autonomic responses (skin conductance and heart rate) did not vary. In most attentional tests, the age-related reduction of RT was associated with increased T, fT and NST and decreased cortisol. 相似文献