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51.
Cyclooxygenase-2 activation mediates the proangiogenic effect of nitric oxide in colorectal cancer. 总被引:14,自引:0,他引:14
Fabio Cianchi Camillo Cortesini Ornella Fantappiè Luca Messerini Iacopo Sardi Nadia Lasagna Federico Perna Valentina Fabbroni Annamaria Di Felice Giuliano Perigli Roberto Mazzanti Emanuela Masini 《Clinical cancer research》2004,10(8):2694-2704
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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Detection and clinical implications of early systemic tumor cell dissemination in breast cancer. 总被引:2,自引:0,他引:2
Klaus Pantel Volkmar Müller Margherita Auer Nathalie Nusser Nadia Harbeck Stephan Braun 《Clinical cancer research》2003,9(17):6326-6334
Blood-borne distant metastasis is the leading cause of cancer-related death in breast cancer. The onset of this fundamental process can now be assessed in cancer patients using ultrasensitive immunocytochemical and molecular assays able to detect even single metastatic cells. Analyses of bone marrow (BM) samples show that disseminated cells are present in 20-40% of primary breast cancer patients without any clinical or histopathological signs of metastasis. The common homing of circulating breast cancer cells in BM is indicative for systemic tumor cell spread and predictive for growth of overt metastases in relevant organ sites such as bone, lung, or liver. Recent clinical studies involving more than 3000 breast cancer patients demonstrated that the presence of tumor cells in BM at primary diagnosis is an independent prognostic factor for unfavorable clinical outcome. To date, sampling of BM, however, is not a routine procedure in clinical management of breast cancer patients. Therefore, several research groups have developed sensitive assays for detection of circulating tumor cells in peripheral blood. Studies evaluating the clinical relevance of these blood assays are ongoing. Here, we will review the existing tumor cell assays and discuss their current clinical relevance and perspectives for the clinical management of breast cancer patients. 相似文献
53.
Flavia Bortolotti MD Massimo Resti MD Raffaella Giacchino MD Chiara Azzari MD Nadia Gussetti MD Carlo Crivellaro MD Cristiana Barbera MD Francesco Mannelli MD Lucia Zancan MD Adalberto Bertolini MD 《The Journal of pediatrics》1997,130(6):990-993
Objective: To evaluate the clinical, biochemical, and virologic features associated with hepatitis C virus (HCV) infection acquired early in life from mothers with antibodies to HCV (anti-HCV).Study design: Multicenter prospective-retrospective study in Italian children.Patients: Two groups of children were investigated. Group 1 included 14 infants, born to mothers with anti-HCV but without human immunodeficiency virus infection, who became seropositive for HCV RNA during the first year of life and were thus considered infected. Group 2 included 16 children with chronic hepatitis C, aged 1
½ to 14 years, whose mothers were the unique potential source of infection. Both groups were followed for 12 to 48 months.Methods: Alanine transaminase (ALT), anti-HCV, and HCV RNA were investigated by the polymerase chain reaction on entry to the study and during follow-up.Results: All children in group 1 had anti-HCV throughout follow-up, and all had ALT abnormalities, ranging from 1.5 to 10.5 times the normal value during the first 12 months. During further follow-up, 5 of 10 children had HCV RNA with abnormal ALT values, 3 had a return to normal of the ALT values but continued to have viremia, and 2 eventually had normal ALT values and clearance of HCV RNA. Of the 16 children in group 2, all were free of symptoms and 62% had only slight ALT elevations; 7 who underwent liver biopsy had histologic features of minimal or moderate hepatitis.Conclusions: HCV infection acquired early in life from mothers with anti-HCV is usually associated with biochemical features of liver damage during the first 12 months of life. Progression to chronicity seems to occur in the majority of cases, although HCV-associated liver disease is likely to be mild throughout infancy and childhood. (J Pediatr 1997;130:990-3) 相似文献
54.
Hansel Nadia N. Wu Albert W. Chang Betty Diette Gregory B. 《Quality of life research》2004,13(3):639-652
Tuberculosis (TB) is a persistent problem in the United States; however, little is known about its impact on functioning and quality of life (QOL) among people with TB. The purpose of this study is to describe the impact of TB on patients' QOL by using focus groups to assess the domains of QOL that are affected. Participants included patients (n = 10) who received treatment for active TB and physicians (n = 4) and nurses (n = 9) caring for patients with TB at a public health clinic in Baltimore, Maryland. TB affected all predicted domains of QOL, including general health perceptions, somatic sensation, psychological health, spiritual well-being, and physical, social and role functioning. Social stigmatization, isolation, pill burden, long duration of therapy, sexual dysfunction, loss of income, and fear were additional specific problems related to TB. Surprisingly, 11% (33) of the comments described benefits of TB illness, including increased spirituality and improved life perspectives. In addition, four additional QOL domains and three elements of treatment specific to TB which substantially impact QOL were identified. While patients and clinicians both identified issues in many areas of QOL, only patients mentioned the impact on sexual function, spirituality and improved life perspectives. Despite available curative therapy, TB and its treatment still have significant short and long-term consequences on patients' QOL. 相似文献
55.
Steffen Robert Tornieporth Nadia Costa Clemens Sue-Ann Chatterjee Santanu Cavalcanti Ana-Maria Collard Françoise De Clercq Norbert DuPont Herbert L. von Sonnenburg Frank 《Journal of travel medicine》2004,11(4):231-238
Background Recent epidemiologic data on travelers— diarrhea (TD) are essential for the evaluation of conventional and future prophylactic and therapeutic measures.
Methods To determine the epidemiology, including risk factors, impact and quality-of-life evaluation of TD, a cross-sectional survey was conducted over 12 months at the airports of Mombasa (Kenya), Goa (India), Montego Bay (Jamaica) and Fortaleza (Brazil) by distributing questionnaires to visitors just prior to their flying home. The study period was March 1996 to July 1998.
Results Overall, 73,630 short-term visitors completed a questionnaire. The total diarrhea attack rate varied between a high of 54.6% in Mombasa and a low of 13.6% in Fortaleza, but only between 31.5% and 5.4% of all travelers had classic TD. The 14-day incidence rates varied between 19.5% and 65.7%. Few travelers meticulously avoided potentially dangerous food items, although in India and Kenya most travelers avoided those considered most dangerous. Risk factors were stays exceeding 1 week, age between 15 and 30 years, and residence in the UK. The impact, measured as incapacity or quality-of-life scores, was very considerable.
Conclusions TD continues to affect vacationers and business travelers as frequently as it did some 20 years ago. Compliance with recommendations to reduce exposure to pathogens by avoiding dangerous food items is poor among travelers from all countries. Implementation of food safety education programs may be difficult to achieve. 相似文献
Methods To determine the epidemiology, including risk factors, impact and quality-of-life evaluation of TD, a cross-sectional survey was conducted over 12 months at the airports of Mombasa (Kenya), Goa (India), Montego Bay (Jamaica) and Fortaleza (Brazil) by distributing questionnaires to visitors just prior to their flying home. The study period was March 1996 to July 1998.
Results Overall, 73,630 short-term visitors completed a questionnaire. The total diarrhea attack rate varied between a high of 54.6% in Mombasa and a low of 13.6% in Fortaleza, but only between 31.5% and 5.4% of all travelers had classic TD. The 14-day incidence rates varied between 19.5% and 65.7%. Few travelers meticulously avoided potentially dangerous food items, although in India and Kenya most travelers avoided those considered most dangerous. Risk factors were stays exceeding 1 week, age between 15 and 30 years, and residence in the UK. The impact, measured as incapacity or quality-of-life scores, was very considerable.
Conclusions TD continues to affect vacationers and business travelers as frequently as it did some 20 years ago. Compliance with recommendations to reduce exposure to pathogens by avoiding dangerous food items is poor among travelers from all countries. Implementation of food safety education programs may be difficult to achieve. 相似文献
56.
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58.
Francesco Scolari Elisa Delbarba Domenico Santoro Loreto Gesualdo Antonello Pani Nadia Dallera Laila-Yasmin Mani Marisa Santostefano Sandro Feriozzi Marco Quaglia Giuliano Boscutti Angelo Ferrantelli Carmelita Marcantoni Patrizia Passerini Riccardo Magistroni Federico Alberici Gian Marco Ghiggeri Claudio Ponticelli Pietro Ravani for the RI-CYCLO Investigators 《Journal of the American Society of Nephrology : JASN》2021,32(4):972
59.