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The authors present a case of an adenoma of the nipple in a 61-year-old man who reported a 6-month history of nodularity and itching at his left nipple. Examination revealed a firm, well-defined, vascularized tumor measuring .8 cm that altered the normal anatomy of the nipple. A total excision of the nipple and areola was performed. The histological diagnosis was adenoma of the nipple. No recurrent tumor has been observed during 4 years of postoperative follow-up. An adequate excision of the lesion is curative without any risk of recurrence or development of malignancy.  相似文献   
104.
IL‐10 is an anti‐inflammatory cytokine that inhibits maturation and cytokine production of dendritic cells (DCs). Although mature DCs have the unique capacity to prime CD8+ CTL, IL‐10 can promote CTL responses. To understand these paradoxic findings, we analyzed the role of IL‐10 produced by human APC subsets in T‐cell responses. IL‐10 production was restricted to CD1c+ DCs and CD14+ monocytes. Interestingly, it was differentially regulated, since R848 induced IL‐10 in DCs, but inhibited IL‐10 in monocytes. Autocrine IL‐10 had only a weak inhibitory effect on DC maturation, cytokine production, and CTL priming with high‐affinity peptides. Nevertheless, it completely blocked cross‐priming and priming with low‐affinity peptides of a self/tumor‐antigen. IL‐10 also inhibited CD1c+ DC‐induced CD4+ T‐cell priming and enhanced Foxp3 induction, but was insufficient to induce T‐cell IL‐10 production. CD1c+ DC‐derived IL‐10 had also no effect on DC‐induced secondary expansions of memory CTL. However, IL‐15‐driven, TCR‐independent proliferation of memory CTL was enhanced by IL‐10. We conclude that DC‐derived IL‐10 selects high‐affinity CTL upon priming. Moreover, IL‐10 preserves established CTL memory by enhancing IL‐15‐dependent homeostatic proliferation. These combined effects on CTL priming and memory maintenance provide a plausible mechanism how IL‐10 promotes CTL responses in humans.  相似文献   
105.
The current definition of gastrointestinal tumors (GIST) as CD117-positive mesenchymal tumors of uncertain malignant potential fails to include a number of cases with similar histology. In an attempt to improve the classification of these neoplasms, we conducted an immunohistochemical analysis of 244 mesenchymal tumors with histological features of GIST. According to their immunophenotype, the tumors were classified as GISTs, which are characterized by CD117 (c-kit) expression; gastrointestinal CD117-negative CD34 positive stromal tumors (GINST); alpha-smooth muscle actin and/or desmin positive gastrointestinal leiomyogenic tumors (GILT); S-100 and glial fibrillary acidic protein positive gastrointestinal glial/schwannian tumors (GIGT); gastrointestinal neuronal/glial tumors (GINT), which are positive for S-100/glial fibrillary acidic protein plus neuronal/glial markers; and gastrointestinal fibrous tumors (GIFT), which are only vimentin positive. The most common type of tumors were GIST, followed in order of frequency by GINST, GILT, GIGT, GIFT, and GINT. GISTs did not show any preferential location, whereas GINSTs occurred almost exclusively in the stomach and duodenum, and GILTs preferentially in the large intestine. Over a median follow-up period of 71 months, malignant behavior, i.e., metastatic spread, was observed in all tumor types except GINTs. Malignancy was associated with distal gut location, high mitotic activity, large tumor size, and nuclear pleomorphism, though none of these criteria alone discriminated between benign and malignant. Kaplan-Meier analysis of disease-specific survival showed significant differences in the long-term outcome of the newly defined subgroups. We conclude that, despite strong morphological similarities, gastrointestinal mesenchymal tumors are heterogeneous in their immunophenotype and biology.  相似文献   
106.
The study aim was to evaluate the effect of different attentional tasks on the amplitudes and latencies of painful and non-painful contact heat evoked potentials (CHEPs). CHEPs were recorded in 12 healthy subjects during two experimental conditions, in which attention was oriented towards the intensity and the distress caused by the stimuli and were compared with CHEPs recorded during a neutral condition. The painful heat stimulation produced a negative potential at Cz vertex with a latency around 540 ms (Cz/N540), a positive peak at Cz electrode around 730 ms (Cz/P730) and, lastly, a positive peak around 1000 ms (Pz/P1000) in the Pz traces. The Cz/P730 wave was significantly higher in amplitude only during the painful stimulation and is probably related to coding the nociceptive activity. Varying the attentional target towards different properties of the stimulus did not cause any significant change in CHEP responses amplitude and latencies compared with the neutral condition. Our results suggest that CHEPs represent a reliable functional measure of the nociceptive pathways and that they are generated by the activation of different cerebral areas involved in pain processing. The high activation level of each of these area or their spatial neighbouring might explain the strong similarity of CHEP components recorded during different attentional manipulations.  相似文献   
107.
In this study we examined the ability of Salmonella enterica serovar Typhimurium porins to activate activating protein 1 (AP-1) and nuclear factor kappaB (NF-kappaB) through the mitogen-activated protein kinase (MAPK) cascade, and we identified the AP-1-induced protein subunits. Our results demonstrate that these enzymes may participate in cell signaling pathways leading to AP-1 and NF-kappaB activation following porin stimulation of cells. Raf-1 was phosphorylated in response to the treatment of U937 cells with porins; moreover, the porin-mediated increase in Raf-1 phosphorylation is accompanied by the phosphorylation of MAPK kinase 1/2 (MEK1/2), p38, extracellular-signal-regulated kinase 1/2, and c-Jun N-terminal kinase. We used three different inhibitors of phosphorylation pathways: 2'-amino-3'-methoxyflavone (PD-098059), a selective inhibitor of MEK1 activator and the MAPK cascade; 4-(4-fluorophenyl)-2-(4-methylsulfinylphenyl)-5-(4-pyridyl)1H-imidazole (SB203580), a specific inhibitor of the p38 pathway; and 7beta-acetoxy-1alpha,6beta,9alpha-trihydroxy-8,13-epoxy-labd-14-en-11-one (forskolin), an inhibitor at the level of Raf-1 kinase. PD-098059 pretreatment of cells decreases AP-1 and NF-kappaB activation by lipopolysaccharide (LPS) but not by porins, and SB203580 pretreatment of cells decreases mainly AP-1 and NF-kappaB activation by porins; in contrast, forskolin pretreatment of cells does not affect AP-1 and NF-kappaB activation following either porin or LPS stimulation. Our data suggest that the p38 signaling pathway mainly regulates AP-1 and NF-kappaB activation in cells treated with S. enterica serovar Typhimurium porins. Antibody electrophoretic mobility shift assays showed that JunD and c-Fos binding is found in cells treated with porins, in cells treated with LPS, and in unstimulated cells. However, by 30 to 60 min of stimulation, a different complex including c-Jun appears in cells treated with porins or LPS, while the Fra-2 subunit is present only after porin stimulation. These data suggest different molecular mechanisms of activation induced by porins or by LPS.  相似文献   
108.
Exogenous allocation of attentional resources allows the visual system to encode and maintain representations of stimuli in visual working memory (VWM). However, limits in the processing capacity to allocate resources can prevent unexpected visual stimuli from gaining access to VWM and thereby to consciousness. Using a novel approach to create unbiased stimuli of increasing saliency, we investigated visual processing during a visual search task in individuals who show a high or low propensity to neglect unexpected stimuli. When propensity to inattention is high, ERP recordings show a diminished amplification concomitantly with a decrease in theta band power during the N1 latency, followed by a poor target enhancement during the N2 latency. Furthermore, a later modulation in the P3 latency was also found in individuals showing propensity to visual neglect, suggesting that more effort is required for conscious maintenance of visual information in VWM. Effects during early stages of processing (N80 and P1) were also observed suggesting that sensitivity to contrasts and medium‐to‐high spatial frequencies may be modulated by low‐level saliency (albeit no statistical group differences were found). In accordance with the Global Workplace Model, our data indicate that a lack of resources in low‐level processors and visual attention may be responsible for the failure to “ignite” a state of high‐level activity spread across several brain areas that is necessary for stimuli to access awareness. These findings may aid in the development of diagnostic tests and intervention to detect/reduce inattention propensity to visual neglect of unexpected stimuli.  相似文献   
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OBJECTIVES: The aim of the study was the pathological and immunohistochemical analysis of cytokeratin 13 (CK13) in intraepithelial cervical tumors. STUDY DESIGN: We studied 415 in situ squamous carcinomas and 13 in situ mucinous cervical type adenocarcinomas of the uterine cervix. All patients underwent laser cervical conization and had a follow-up ranging 12-135 months. RESULTS: 3% of the squamous carcinoma patients recurred during the follow-up period, while the percentage of recurrence of in situ adenocarcinoma patients was 7.6%. We observed positive surgical edges in 46.1% of glandular tumors, and in 5% of squamous tumors. The percentage of recurrence was high among the cases with positive borders independently from their histopathologic type (14.3% in the squamous carcinomas versus 50% in the adenocarcinomas), compared to cases with negative edges (2.3% in the squamous carcinomas versus 0% in the adenocarcinomas). We observed CK13 positive staining in cervical squamous tumors and in mucinous cervical type adenocarcinomas, while there was no positive staining in non-neoplastic cervical glandular elements. CONCLUSION: CK13 positive immunostaining among in situ squamous and in situ mucinous cervical type adenocarcinoma cases adds additional evidence to data supporting a common origin of the two lesions.  相似文献   
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