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21.
Several of the major variable factors in the Syrian hamster embryo/simian adenovirus SA7 (SHE/SA7) viral enhancement assay were identified and the effects of these parameters on assay sensitivity were assessed. The extent of dose-dependent cytotoxicity and enhancement of SA7 transformation of primary SHE target cells by benzo(a)pyrene was examined through analysis of data obtained from 37 assays performed over a 2-year period. The variables analyzed for contribution to assay sensitivity included the number of SA7-induced transformed SHE cell foci enumerated in ten replicate dishes in the negative control condition (background focus count) (range: 26-139); the age of the SHE cell cultures at the time of exposure to benzo(a)pyrene (range: 72-144 hr postseeding); and the source of the pregnant hamsters used to prepare the primary SHE cells (Wilmington colony vs Lakeview colony, Charles River Laboratories, Inc., Wilmington, MA). The benzo(a)pyrene-induced cytotoxicity and enhancement of SA7 transformation responses were found to be independent of each of these variables, within the range of values tested.  相似文献   
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The histochemical binding pattern of the peanut (Arachis hypogaea) lectin (PNA) was quantitatively described by means of computer-assisted microscope analysis in 28 benign prostatic hyperplasias (BPH), 15 prostatic intraepithelial neoplasias (PIN), and 119 prostatic adenocarcinomas. PNA exhibits noninunune but selective binding to glycoproteins with β-D-galactosyl(1,3)-N-acetyl-D-galactosamine residues. We also investigated whether a relationship existed between the number of histochemical-related PNA acceptors and the histochemical prostate-specific antigen (PSA) stain intensity, and between the number of PNA receptors and DNA ploidy level. The results show that neoplastic prostate tissues and high-grade intraepithelial prostatic neoplasias (PIN2_3) exhibit a significantly higher number of PNA acceptors than benign prostatic hyperplasias and low (PIN1) grade prostatic intraepithelial neoplasias. A statistically significant correlation was observed between the number of histochemically related PNA acceptors and PSA immunostain intensity. Lastly, diploid prostatic tumors, whether benign or malignant, exhibited a significantly higher number of PNA acceptors than aneuploid ones. These results suggest that PNA acceptors play an important role in the biology of prostate tumors.  相似文献   
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We investigated the reaction of the cellular immune system of liver and blood in the C57BL/6 mouse to a metastasizing Lewis lung carcinoma. The cellular immune system of the liver consists of mature and immature macrophages, B-cells, T-cells including their subpopulations, and natural killer cells, and their percentage frequencies differ significantly from those in the corresponding mononuclear blood cell (MBC) compartment. This suggests that the hepatic immune cells represent a system with autonomous function showing a typical homing of its members. Imminent metastasis to the liver is signalled by impressive alterations in the percentage frequencies of nonparenchymal liver cells (NPLC). There are a dramatic loss of mature macrophages, an increase in immature macrophages, a reduction of T-helper cells leading to a low CD4/CD8 ratio, and an increase in natural killer cells. In the blood, the corresponding precursor cells show comparable changes with a delay of at least 2 days. Early metastasis is accompanied by a significant increase in mononuclear NPLC producing tumour necrosis factor . The alterations in percentage frequencies of the NPLC during tumour metastasis differ markedly from the changes in these cells in the liver during endotoxinaemia.  相似文献   
25.
A silver staining technique for nucleolar organizer regions (NORs) has been applied to bone marrow biopsies of various types of acute and chronic leukaemias. This method could be easily evaluated on resin-embedded bone marrow obtained from acute lymphocytic leukaemia (n = 12), acute myelogenous (n = 16), chronic lymphocytic (n = 16) and chronic granulocytic (n = 20) leukaemia. A significant difference (p < or = 0.1) was only found between the AgNOR numbers in nuclei of lymphocytes from acute and chronic leukaemia (mean of 1.23 to 1.40 and 1.58) and those of cells from acute and chronic myelogenous leukaemia (from a mean of 5.00 to 9.17 per nucleus). However, no significant difference was observed among cells of various types of acute and chronic myelogenous leukaemias, despite of their markedly higher staining intensity and proliferative activity. The greatest mean of AgNOR numbers was counted in monoblasts of acute myelomonocytic leukaemia. It is suggested, that higher AgNOR counts in nuclei of more malignant leukaemic cells are in parallel with their mitotic activity and could be related to their elevated cell turn-over.  相似文献   
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It has been previously shown that S100A2 is down-regulated in tumor cells and can be considered a tumor suppressor. We have recently shown that this down-regulation can be observed particularly in epithelial tissue, where S100A2 expression decreases remarkably in tumors as compared with normal specimens. In the present paper we investigate whether S100A2 could play a tumor-suppressor role in certain epithelial tissues by acting at the cell migration level. To this end, we made use of five in vitro human head and neck squamous cell carcinoma lines in which we characterized S100A2 expression at both RNA and protein level. To characterize the influence of S100A2 on cell kinetic and cell motility features, we used two complementary approaches involving specific antisense oligonucleotides and the addition of S100A2 to the culture media. The different expression analyses gave a coherent demonstration of the fact that the FADU and the RPMI-2650 cell lines exhibit high and low levels of S100A2 expression, respectively. Antisense oligonucleotides (in FADU) and extracellular treatments (in RPMI) showed that, for these two models, S100A2 had a clear inhibitory influence on cell motility while modifying the cell kinetic parameters only slightly. These effects seem to be related, at least in part, to a modification in the polymerization/depolymerization dynamics of the actin microfilamentary cytoskeleton. Furthermore, we found evidence of the presence of the receptor for advanced glycation end-products (RAGE) in RPMI cells, which may act as a receptor for extracellular S100A2. The present study therefore presents experimentally based evidence showing that S100A2 could play a tumor-suppressor role in certain epithelial tissues by restraining cell migration features, at least in the case of head and neck squamous cell carcinomas.  相似文献   
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This study aims to investigate whether the immunohistochemical levels of expression of galectin-3 and the macrophage migration inhibitory factor (MIF) are associated with prognostic values in human colorectal tumors. This was performed on 99 specimens including 69 colorectal tumors (17 Dukes A, 19 Dukes B, 15 Dukes C and 18 metastatic tumors that we labeled as D), 10 hepatic metastases from colorectal cancers and 20 normal specimens (biopsies). The immunohistochemical levels of expression of MIF and galectin-3 were quantified on routine histological slides by means of computer-assisted microscopy. Separate analyses were performed on epithelial and connective tissue. The levels of expression of both MIF and galectin-3 were very significantly higher in epithelial tumor tissue when compared with normal epithelial specimens. A positive and significant correlation between MIF and galectin-3 expression was evidenced in connective tumor tissue, and in particular in the cases associated with short survival periods (less than 5 years). In the case of the Dukes A or B tumors, we established two new prognostic groups (labeled I and II) on the basis of the levels of galectin-3 expression measured in the tumor epithelium. In the case of the Dukes C or D tumors, we established two other prognostic groups (labeled III and IV) on the basis of the levels of MIF expression measured in the connective tissue. Kaplan-Meyer analyses confirmed the additional prognostic values (as compared with conventional clinical staging) given by this new classification (groups I to IV). They show that the Dukes A or B tumors characterized by low levels of galectin-3 expression in the tumor epithelium are associated with significantly better prognoses than those characterized by high levels. In addition, the Dukes C or D tumors characterized by high levels of MIF expression in the connective tumor tissue are associated with significantly better prognoses than those characterized by low levels. In conclusions, MIF and galectin-3 expression levels in colorectal tumors are related to their levels of biological aggressiveness. These markers could be used to identify patients at risk, for whom more aggressive adjuvant therapy seems to be indicated.  相似文献   
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Total elbow arthroplasty as a treatment option for open elbow fracture is relatively rare described. We reported a 39 years old polytrauma patient with complex open elbow fracture (Gustilo-Anderson type IIIB). The patient presented with large soft tissues defect on dorsal part of the left elbow, ulnar palsy due to the irreparable loss of the ulnar nerve, distal triceps loss due to the complete loss of the olecranon, loss of both humeral condyles with collateral ligaments and complex elbow instability. Only few similar cases have been published. Reconstructive surgery included repetitive radical debridement, irrigation, vacuum assisted closure system therapy, external fixation, coverage of the soft tissue defect with fascia ecutaneous flap from the forearm. Four months after the injury, total elbow arthroplasty with autologous bone graft (from the proximal radius) inserted in the ulnar component, was performed. At 3 years postoperatively, the patient is able to perform an active flexion from 0 to 110 with full pronosupination. Only passive extension is allowed. The ulnar neuropathy is persistent. Patient has no signs of infection or loosening of the prosthesis.  相似文献   
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