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51.
Following improvements in therapy for childhood malignancies, the striking increase in survival rate over the past 30 years has led to the increase risk of developing second malignant neoplasms (SMNs). We report a case of colorectal carcinoma as a SMN, following treatment for rhabdomyosarcoma. The patient was diagnosed with rhabdomyosarcoma of the urinary bladder at his age of three years, and developed adenocarcinoma in the colon 13 years later. Histologic examination of the surgical specimen revealed adenocarcinoma involving the rectosigmoid area with radiation colitis in its background. The tumor cells showed strong immunoreactivity for p53 protein, suggesting the role of irradiation and p53 mutation in carcinogenesis. This case emphasizes the need for dose observation in survivors of early childhood malignancies treated with radiation and multiagent chemotherapy.  相似文献   
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53.
The activation of eukaryotic heat shock protein (Hsp) gene expression occurs in response to a wide variety of cellular stresses including heat shock, hydrogen peroxide, uncoupled oxidative phosphorylation, infection, and inflammation. Biochemical and genetic studies have clearly demonstrated critical roles for mammalian heat shock factor 1 (HSF1) in stress-inducible Hsp gene expression, resistance to stress-induced programmed cell death, extra-embryonic development, and other biological functions. Activation of mammalian Hsp gene expression involves the stress-inducible conversion of HSF1 from the inactive monomer to the DNA-binding competent homotrimer. Although Hsp activation is a central conserved process in biology, the precise mechanisms for stress sensing and signaling to activate HSF1, and the mechanisms by which many distinct stresses activate HSF1, are poorly understood. In this report we demonstrate that recombinant mammalian HSF1 directly senses both heat and hydrogen peroxide to assemble into a homotrimer in a reversible and redox-regulated manner. The sensing of both stresses requires two cysteine residues within the HSF1 DNA-binding domain that are engaged in redox-sensitive disulfide bonds. HSF1 derivatives in which either or both cysteines were mutated are defective in stress-inducible trimerization and DNA binding, stress-inducible nuclear translocation and Hsp gene trans-activation, and in the protection of mouse cells from stress-induced apoptosis. This redox-dependent activation of HSF1 by heat and hydrogen peroxide establishes a common mechanism in the stress activation of Hsp gene expression by mammalian HSF1.  相似文献   
54.
Vascular endothelial growth factor (VEGF) is known to play a key role in tumor angiogenesis. The tumor-suppressor gene p53 has been thought to regulate VEGF. We investigated the effect of VEGF on esophageal carcinoma and the correlation between VEGF and p53. Tissue samples were taken from 81 patients with esophageal carcinoma after surgery. VEGF and p53 expressions were examined by immunohistochemical staining. Microvessels in the tumor stained for CD34 antigen were also counted. VEGF and p53 expressions were observed in 51.3% (41/80) and 51.9% (41/79), respectively. The microvessel density was 70.9+/-6.7 (mean+/-SE) in VEGF-positive group and 68.7+/-5.1 in VEGF-negative group. However, no correlation was noted between VEGF and p53 expression. Whereas the tumor size, nodal status, depth of invasions, and tumor stage were associated with poor overall survival, VEGF expression or p53 expression was not. These results indicate that VEGF and p53 are highly expressed in esophageal carcinomas. Since the VEGF expression is not correlated with the p53 expression, microvessel density or clinicopathological findings, further studies with other angiogenic molecules are needed to determine the role in esophageal carcinomas.  相似文献   
55.
Theophylline has been widely used to treat apnea of premature neonates. The purpose of this study was to compare the pharmacokinetic parameters of theophylline and caffeine after intravenous administration of aminophylline to seven Korean low-birthweight neonates with apnea to those in other countries. The serum concentrations of theophylline and caffeine were measured simultaneously by high-performance liquid-chromatography (HPLC). The mean (+/- S.E.M.) birth weight and gestational period were 1190 +/- 253 g and 31.5 +/- 1.99 weeks, respectively. The mean (+/- S.E.M.) theophylline maintenance dosage was 1.28 +/- 0.15 mg/kg (given as equivalent aminophylline solution) every six hours. The mean (+/- S.E.M.) volume of distribution, 0.937 +/- 0.232 l/kg, elimination rate constant, 0.0249 +/- 0.0095/h, elimination half-life, 32.1 +/- 12.1 h, and total body clearance, 21.7 +/- 6.18 ml/h/kg, of theophylline in Korean premature neonates were comparable to the values of neonates in other countries. For caffeine, the mean (+/- S.E.M.) elimination half-life was 95.1 +/- 25.4 h and the elimination rate constant was 0.0079 +/- 0.0024/h. The mean (+/- S.E.M.) serum concentrations of theophylline and caffeine on the sixth day after aminophylline infusion were 10.4 +/- 2.28 microg/ml (range, 6.38-13.4 microg/ml) and 2.94 +/- 0.98 microg/ml (range, 1.80-4.44 microg/ml), respectively. The mean (+/- S.E.M.) caffeine to theophylline concentration ratio on the day after discontinuation of aminophylline infusion was 0.71 +/- 0.23 (range, 0.39-1.03).  相似文献   
56.
In most cases, while schwannoma is sporadically manifested as a single benign neoplasm, the presence of multiple schwannomas in one patient is usually indicative of neurofibromatosis 2. However, several recent reports have suggested that schwannomatosis itself may also be a distinct clinical entity. This study examines an extremely rare case of probable schwannomatosis associated with intracranial, intraspinal and peripheral involvements. A 63-year-old woman presented with a seven-year history of palpable lumps on both sides of the supraclavicular area and hearing impairment in both ears. On physical examination, no skin manifestations were evident. Facial sensory change, deafness in the left ear and decreased gag reflex were revealed by neurological examination. Magnetic resonance imaging revealed multiple lesions of the trigeminal nerves, acoustic nerves, lower cranial nerves, spinal accessory nerve, brachial plexuses, and spinal nerves. Pathological examination of tumors from the bilateral brachial plexuses, the spinal nerve in the T8 spinal position and the neck mass revealed benign schwannomas. Following is this patient case report of multiple schwannomas presenting with no skin manifestations of neurofibromatosis.  相似文献   
57.
Giant-cell interstitial Pneumonia (GIP) is a very uncommon respiratory disease. The majority of cases of GIP are caused by exposure to cobalt, tungsten and other hard metals. In this report, we describe GIP in a patient who worked in gas station and dealt in propane gas vessels. He presented with clinical features of chronic interstitial lung disease and underwent an open lung biopsy that showed DIP-like reaction with large numbers of intra-alveolar macrophages and numerous large, multinucleated histiocytes which were admixed with the macrophages. Analysis of lung tissue for hard metals was done. Cobalt was the main component of detected hard metals. Corticosteroid therapy was started and he recovered fully.  相似文献   
58.
Virus associated hemophagocytic syndrome (VAHS) are a heterogeneous group of disorders in which viral infection is associated with a proliferation of hemophagocytic histiocytes through the reticuloendothelial system. We report the case of a 21-year-old Korean man who presented to us with high fever, marked hepatosplenomegaly, severe hepatic dysfunction, coagulopathy, pancytopenia and marked panhypogammaglobulinemia. Bone marrow aspiration and biopsy showed histiocytes proliferation with active phagocytosis of red cells and neutrophils. Primary Epstein-Barr (EB) viral infection at presentation was confirmed by the presence of IgM antibody to viral capsid antigen (VCA) with absence of antibody to EB viral nuclear antigen (EBNA). A liver biopsy performed one month after the presentation showed erythrophagocytic histiocytes within the sinusoids. EB virus was demonstrated in the liver biopsy tissue by DNA PCR method, and EBER mRNA in situ hybridization.  相似文献   
59.
Spontaneous acute tumor lysis syndrome with advanced gastric cancer   总被引:3,自引:0,他引:3  
Acute tumor lysis syndrome (TLS) occurs frequently in hematologic malignancies such as high-grade lymphomas and acute leukemia, which are rapidly proliferating and chemosensitive tumors. It occurs rarely in solid tumors and has never been reported in gastric adenocarcinoma. Typical biochemical findings of acute tumor lysis syndrome are hyperuricemia, hyperkalemia, hyperphosphatemia and hypocalcemia in patients with a malignancy. Rapid changes of these electrolytes may cause cardiac arrhythmia, seizure, acute renal failure and sudden death. Therefore, as soon as it is detected, it should be taken care of immediately. Until now almost all cases of TLS associated with solid tumor have developed after cytoreductive therapy in chemosensitive tumors. We report here a case of spontaneous acute tumor lysis in a patient of advanced gastric cancer with hepatic metastases and multiple lymphadenopathy. The biochemical finding of TLS improved with the management and tumor burden also showed slight response to the one cycled combination chemotherapy but the patient died of progressive pneumonia.  相似文献   
60.
To investigate whether the phosphorylation of extracellular signal-regulated kinase (ERK) is involved in autoimmune injury of the peripheral nervous system (PNS), the expression of phosphorylated ERK (p-ERK) was analyzed in experimental autoimmune neuritis (EAN) in rats. Western blot analysis showed that the level of p-ERK was increased significantly in the sciatic nerves of rats on days 14 (p<0.05) and 24 (p<0.01) post-immunization, compared with controls, and its reaction declined at day 30 post-immunization. Immunohistochemistry showed that p-ERK protein was weakly expressed in Schwann cells and vascular endothelial cells in the sciatic nerves of CFA-immunized control rats. In EAN-affected sciatic nerves, p-ERK immunoreactivity was found mainly in ED1-positive macrophages on days 14 and 24 post-immunization. Moreover, on days 24 and 30 post-immunization, p-ERK immunoreactivity increased gradually in the Schwann cells of rat sciatic nerves with EAN. Based on these results, we postulated that the phosphorylation of ERK has an important role in the differentiation and survival of cells, including inflammatory cells and Schwann cells, in the rat sciatic nerve in EAN. Specifically, the activation of ERK in the recovery phase of EAN paralysis seems to be related in the survival of Schwann cells.  相似文献   
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