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81.
The role of particulate matter-associated zinc in cardiac injury in rats   总被引:1,自引:0,他引:1  
BACKGROUND: Exposure to particulate matter (PM) has been associated with increased cardiovascular morbidity; however, causative components are unknown. Zinc is a major element detected at high levels in urban air. OBJECTIVE: We investigated the role of PM-associated zinc in cardiac injury. METHODS: We repeatedly exposed 12- to 14-week-old male Wistar Kyoto rats intratracheally (1x/week for 8 or 16 weeks) to a) saline (control); b) PM having no soluble zinc (Mount St. Helens ash, MSH); or c) whole-combustion PM suspension containing 14.5 microg/mg of water-soluble zinc at high dose (PM-HD) and d ) low dose (PM-LD), e) the aqueous fraction of this suspension (14.5 microg/mg of soluble zinc) (PM-L), or f ) zinc sulfate (rats exposed for 8 weeks received double the concentration of all PM components of rats exposed for 16 weeks). RESULTS: Pulmonary inflammation was apparent in all exposure groups when compared with saline (8 weeks > 16 weeks). PM with or without zinc, or with zinc alone caused small increases in focal subepicardial inflammation, degeneration, and fibrosis. Lesions were not detected in controls at 8 weeks but were noted at 16 weeks. We analyzed mitochondrial DNA damage using quantitative polymerase chain reaction and found that all groups except MSH caused varying degrees of damage relative to control. Total cardiac aconitase activity was inhibited in rats receiving soluble zinc. Expression array analysis of heart tissue revealed modest changes in mRNA for genes involved in signaling, ion channels function, oxidative stress, mitochondrial fatty acid metabolism, and cell cycle regulation in zinc but not in MSH-exposed rats. CONCLUSION: These results suggest that water-soluble PM-associated zinc may be one of the causal components involved in PM cardiac effects.  相似文献   
82.
Benign testicular teratomas are always thought to be pediatric neoplasms and previously all the teratoid tumors in the adult testis regarded as malignant. Recently, three publications reported benign testicular teratomas in adulthood and the latest WHO classification refers them as “prepubertal type of teratomas” which rarely appear in adulthood. These neoplasms behave benign and seemingly analogous independently whether they appear in pre- or postpubertal patients. The aim of our study was to investigate the frequency of benign testicular teratomas both in children and adults. 593 cases of testicular neoplasms were found in a period of 17 years ranging from 1998 to 2014 in the archive of our department (Department of Pathology, Medical Center, Pécs University). 543 cases diagnosed as germ cell tumor which have all been further evaluated in conjunction with the clinical data available. Of all germ cell tumor cases 14 (2.5 %) were pure teratomas. Ten out of 14 were the WHO-defined “conventional” teratoma, 4 of the 14 were the “benign or the so called prepubertal type” from which three occurred in adult patients. Only one of the 14 occurred in childhood, indicating that benign prepubertal type teratomas –which are regarded generally as childhood tumors- are more frequently detected in adults than in children. Benign adult testicular teratomas comprised 21 % of all pure teratoma cases in our series. Practicioners in the field have to be aware of its existence also in adulthood to avoid overtreatment and not to expose their patients to unnecessary chemotherapy, retroperitoneal lymphadenectomy (RLA) and the potential complications of these interventions.  相似文献   
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We studied two cases of pigmented neuroectodermal tumor of infancy (PNTI) by routine light microscopy and immunohistochemistry on formalin fixed, paraffin embedded tissues using antibodies to HMB-45 "melanoma associated" antigen, S-100 protein, neuron specific enolase (NSE), Leu-7 antigen, chromogranin, epithelial membrane antigen, collagen Type IV, alpha-fetoprotein and muscle-specific actin and to the intermediate filaments cytokeratin (CK), vimentin, desmin and neural filaments. We found that the large epithelioid cells, many of which contained melanin pigment, were strongly positive for CK and HMB-45, and less intensively positive for vimentin and NSE. The small neuroblast-like cells revealed only focal, weak NSE positivity. Both cell types were negative for S-100 protein and for the other antigens examined. Our results suggest that: (1) the large and small cell populations in PNTI have different immunophenotypes; (2) the expression of CK and HMB-45, together with the S-100 negativity, appears unique for the pigmented cells; and (3) this profile may be helpful in the exclusion of melanoma and peripheral neuroblastoma from the differential diagnosis.  相似文献   
85.
Prostate cancer remains the second leading cause of cancer deaths among American men. Early diagnosis increases survival rate in patients; however, treatments for advanced disease are limited to hormone ablation techniques and palliative care. Thus, new methods of treatment are necessary for inhibiting prostate cancer disease progression. Here, we have shown that miRNA-29b (miR-29b) expression was lower in prostate cancer cells (PC3 and LNCaP) as compared with immortalized prostate epithelial cells. Between these two prostate cancer cell lines, metastatic prostate cancer PC3 cells displayed lower expression of miR-29b. We also observed a significant downregulation of miR-29b expression in human prostate cancer tissues as compared with patient-matched nontumor tissues. PC3 cells ectopically expressing miR-29b inhibited wound healing, invasiveness, and failed to colonize in the lungs and liver of severe combined immunodeficient mice after intravenous injection, while PC3 cells expressing a control miRNA displayed metastasis. Epithelial cell marker E-cadherin expression was enhanced miR-29b transfected in prostate cancer cells as compared with cells expressing control miRNA. On the other hand, N-cadherin, Twist, and Snail expression was downregulated in PC3 cells expressing miR-29b. Together these results suggested that miR-29b acts as an antimetastatic miRNA for prostate cancer cells at multiple steps in a metastatic cascade. Therefore, miR-29b could be a potentially new attractive target for therapeutic intervention in prostate cancer.  相似文献   
86.
BackgroundMidnight salivary cortisol (MSC) concentration has been considered as a sensitive marker of overt hypercortisolism. Because no studies on commercially available automated, non-isotopic MSC assays have been reported, we determined and compared the diagnostic performance of an automated electrochemiluminescent immunoassay (ECLIA, Elecsys E170) and an in-house radioimmunoassay (RIA) for MSC measurement.MethodsThe study involved 126 consecutive patients referred for evaluation because of symptoms of Cushing's syndrome, obesity, or the presence of incidentally discovered adrenal adenoma. Using detailed clinical, hormonal and radiological evaluation overt endogenous hypercortisolism was confirmed in 9 patients and was excluded in 117 patients.ResultsROC analysis indicated that the best performance of MSC was obtained at cutoff value of 0.35 µg/dl using ECLIA (sensitivity, 100%; specificity, 88%) and 0.29 µg/dl (sensitivity, 100%; specificity, 71%) using RIA. When the findings were compared to those obtained from low dose dexamethasone test, both ECLIA and RIA of MSC showed a better diagnostic performance.ConclusionMSC measurement is useful for the diagnosis of overt hypercortisolism but the cutoff value is highly dependent on the method used. We recommend the use of automated ECLIA for MSC assay, and we propose further studies on other automated immunoassay analyzers potentially suitable for MSC measurements.  相似文献   
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Osteomyelitis often eludes early diagnosis because plain film radiography is too insensitive and radionuclide bone scanning is nonspecific. In this study, 90 diabetic patients were studied with plain film and magnification radiographs of their feet. Among the 24 patients with osteomyelitis, plain radiographs suggested the diagnosis in 14 patients and magnification radiography was diagnostic in 18 of these patients. Thus, magnification radiography offers some diagnostic advantage in patients suspected of having osteomyelitis.  相似文献   
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