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21.
Vinyl chloride (VC), a volatile substance mostly used for polyvinyl chloride (PVC) synthesis, is a systemic toxicant particularly noxious to endothelium. Angiosarcoma of the liver, Raynaud's phenomenon, scleroderma-like lesions, acroosteolysis and neuritis are known to be typical vinyl chloride-associated manifestations (VC disease). A so far unknown feature of the disease is purpura. This was first observed by the authors in a worker of a PVC-producing plant. The skin eruption was characterized by small purpuric maculae with tiny, palpable spots and papulae, mostly concentrated on the lower part of the legs, changing into bullae, pustules and crusts and tending to spontaneous regression after withdrawal from VC exposure. A skin biopsy revealed marked inflammatory reaction with a mostly lymphocytic and histiocytic infiltration around and in the walls of dermal arterioles. The finding of increased circulating immune complexes and anti-smooth muscle autoantibodies strengthens the hypothesis that immunologic changes play a role in the appearance of "vinylic purpura."  相似文献   
22.
Neurosurgical Review - The current literature regarding surgical treatment for tumors in the sphenopetroclival (SPC) region is merely scarce. Through a comprehensive literature review, we...  相似文献   
23.
BackgroundInjury to kidney podocytes often results in chronic glomerular disease and consecutive nephron malfunction. For most glomerular diseases, targeted therapies are lacking. Thus, it is important to identify novel signaling pathways contributing to glomerular disease. Neurotrophic tyrosine kinase receptor 3 (TrkC) is expressed in podocytes and the protein transmits signals to the podocyte actin cytoskeleton.MethodsNephron-specific TrkC knockout (TrkC-KO) and nephron-specific TrkC-overexpressing (TrkC-OE) mice were generated to dissect the role of TrkC in nephron development and maintenance.ResultsBoth TrkC-KO and TrkC-OE mice exhibited enlarged glomeruli, mesangial proliferation, basement membrane thickening, albuminuria, podocyte loss, and aspects of FSGS during aging. Igf1 receptor (Igf1R)–associated gene expression was dysregulated in TrkC-KO mouse glomeruli. Phosphoproteins associated with insulin, erb-b2 receptor tyrosine kinase (Erbb), and Toll-like receptor signaling were enriched in lysates of podocytes treated with the TrkC ligand neurotrophin-3 (Nt-3). Activation of TrkC by Nt-3 resulted in phosphorylation of the Igf1R on activating tyrosine residues in podocytes. Igf1R phosphorylation was increased in TrkC-OE mouse kidneys while it was decreased in TrkC-KO kidneys. Furthermore, TrkC expression was elevated in glomerular tissue of patients with diabetic kidney disease compared with control glomerular tissue.ConclusionsOur results show that TrkC is essential for maintaining glomerular integrity. Furthermore, TrkC modulates Igf-related signaling in podocytes.  相似文献   
24.
Annals of Surgical Oncology - Biomarker changes in patients with residual disease (RD) after neoadjuvant systemic therapy (NAT) have unclear consequences. This study examined the prevalence of...  相似文献   
25.
For women with breast cancer in whom multiple Oncotype DX® Recurrence Scores (RS) are obtained, RS concordance utilizing current NCCN recommendations has not been evaluated. Patients with two or more RS were identified. RS were stratified by NCCN guidelines and compared for concordance. Twenty-four patients were evaluated. RS concordance varied by tumor type: 100% in the same tumor, 91.7% in multiple ipsilateral tumors, 71.4% in contralateral tumors, and 66.7% in in-breast recurrent tumors. RS concordance for multiple assays in the same patient is not high enough to omit Oncotype DX® testing for each tumor.  相似文献   
26.
The parallel emergence of uterus transplantation (UTx) and other transplantation innovations including face and hand transplantation led to the categorization of the uterus as a vascular composite allograft (VCA). With >60 transplants and >20 births worldwide, UTx is transitioning rapidly from a research endeavor to an effective treatment option for women with uterine factor infertility. While it originally made sense to group the innovations under one umbrella, it is time to revisit the designation of UTx as a VCA. We describe how UTx needs unique policy, procedural codes, insurance contracts, and educational initiatives. We contend that separating UTx from VCAs may become necessary in the future to avoid hindering the growth and regulation of this field.  相似文献   
27.

Obituary

Professor Giuseppe Satta, MD 1942–1994 Associate Editor European Journal of Epidemiology  相似文献   
28.
Sentinel lymph node dissection is a minimally invasive surgical technique for staging of breast carcinoma. The optimal pathologic examination of the sentinel node (SN) has not yet been determined. Our standard protocol for evaluation of the SN in patients with breast cancer included frozen section at one level, plus paraffin sections at two levels, separated by 40 microm, and stained with hematoxylin and eosin and cytokeratin immunohistochemistry (IHC) at each paraffin section level. In the current study, we evaluated the use of step sections and cytokeratin IHC in 60 SNs (42 consecutive patients) that were tumor-negative on frozen section and hematoxylin and eosin staining at permanent section levels 1 and 2. The SN were reexamined with cytokeratin IHC at eight additional levels (levels 3-10) of the paraffin block, each separated by 40 microm. Previous IHC sections from levels 1 and 2 had shown micrometastases in nine SNs (eight patients) and no tumor cells in the remaining 51 SNs (34 patients). Of the 51 previously negative SNs, only two (4%) SNs from one (3%) patient had metastatic carcinoma cells in levels 3-10. Thus, the additional step sections with cytokeratin IHC did not significantly increase the number of patients with tumor-positive SNs. We currently recommend that the SN be examined with cytokeratin IHC at two levels of the paraffin block. This should optimize sentinel lymph node dissection as a staging technique and minimize the labor and financial burden associated with multiple step sections and IHC stains.  相似文献   
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30.
PURPOSE: Up-regulation of both inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) enzymes has been reported in colorectal cancer. We aimed at evaluating the possible interaction between the nitric oxide and COX-2 pathways, and its effect on promoting tumor angiogenesis. EXPERIMENTAL DESIGN: Expression of iNOS, COX-2, vascular endothelial growth factor (VEGF), and CD31 was analyzed in tumor samples and corresponding normal mucosa obtained from 46 surgical specimens. We also evaluated iNOS activity, prostaglandin E(2) (PGE(2)), cyclic GMP and cyclic AMP production in the same specimens. Nitrite/nitrate levels, and PGE(2) and VEGF production were assessed in HCT116 and HT29 colon cancer cell lines after induction and selective inhibition of the two enzyme pathways. RESULTS: A significant correlation was found between iNOS and COX-2 immunohistochemical expression. PGE(2) production significantly correlated with iNOS activity and cGMP levels. A significant correlation was also found among PGE(2) production, microvessel density, and VEGF expression. Coinduction of both iNOS and COX-2 activities occurred after lipopolysaccharide (LPS) and epidermal growth factor (EGF) treatment in HCT116 and HT29 cells. Inhibition of iNOS by 1400W significantly reduced both LPS- and EGF-induced PGE(2) production. Treatment with LPS, EGF, and arachidonic acid significantly increased VEGF production in the iNOS-negative/COX-2-positive HT29 cells. This effect was completely reversed by treatment with the selective COX-2 inhibitor celecoxib. CONCLUSIONS: Our data showed a prominent role of nitric oxide in stimulating COX-2 activity in colorectal cancer. This interaction is likely to produce a cooperative effect in promoting angiogenesis through PGE(2)-mediated increase in VEGF production.  相似文献   
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