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61.
Cyclooxygenase-2 is a target of KRASD12, which facilitates the outgrowth of murine C26 colorectal liver metastases. 总被引:5,自引:0,他引:5
Niels Smakman Onno Kranenburg Jan M Vogten Alexander L A Bloemendaal Paul van Diest Inne H M Borel Rinkes 《Clinical cancer research》2005,11(1):41-48
PURPOSE: Mutational activation of the KRAS oncogene and overexpression of cyclooxygenase-2 (COX-2) contribute to colorectal carcinoma (CRC) development, but the relationship between these two events is unclear. This study was designed to clarify that relationship and to assess the contribution of KRAS-dependent COX-2 to the seeding of CRC cells in the liver and to their outgrowth as liver metastases in an experimental mouse model. EXPERIMENTAL DESIGN: The effect of RNA interference-mediated KRAS knockdown on COX-2 expression and activity was tested in murine C26 CRC cells. The contribution of KRAS-dependent COX-2 to early metastatic tumor cell seeding (by intravital microscopy) and outgrowth of metastases in the liver (by bioluminescence imaging) was studied by using parecoxib, a novel and highly selective liver-activated COX-2 inhibitor. Intratumoral cell proliferation, apoptosis, and tumor-associated angiogenesis were assessed by immunohistochemistry on liver tissue sections. RESULTS: Stable knockdown of mutant KRAS(D12) in murine C26 CRC cells by RNA interference lead to a dramatic reduction of COX-2 synthesis and prostaglandin E2 production. Inhibition of host or tumor cell COX-2 activity had no effect on early metastatic cell seeding in the liver but greatly reduced intrahepatic tumor cell proliferation and the rate of liver metastasis outgrowth. COX-2 inhibition had no effect on early tumor vascularization or on tumor cell apoptosis. CONCLUSIONS: The high levels of COX-2 enzyme and prostaglandin production in C26 CRC cells are primarily caused by the presence of endogenous mutant KRAS(D12). Furthermore, COX-2 inhibition affects the tumoral rather than the vascular compartment during the early stages of C26 liver metastasis outgrowth. 相似文献
62.
Simultaneous quantification of isoniazid,rifampicin, ethambutol and pyrazinamide by liquid chromatography/tandem mass spectrometry
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Julie B. Prahl Marika Lundqvist Justyna M. C. Bahl Isik S. Johansen Åse B. Andersen Niels Frimodt‐Møller Arieh S. Cohen 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2016,124(11):1004-1015
A remediable cause of poor treatment response in drug‐susceptible tuberculosis (TB) patients may be low plasma levels of one or more of the first‐line anti‐TB drugs. The aim of this work was to develop an accurate and precise LC‐MS/MS method for simultaneous quantification of all four first‐line anti‐TB drugs in plasma suitable for therapeutic drug monitoring (TDM). To adjust for degradation and losses during sample preparation, isotopically labeled compounds were used as internal standards. Plasma samples spiked with internal standards were extracted using protein precipitation with methanol and acetonitrile. Simultaneous separation of all four drugs was accomplished with a Chromolith Reversed‐Phase column and mobile phases consisting of water, methanol, ammonium acetate and formic acid with subsequent mass spectrometric quantification. The linear range of the calibration curve for isoniazid was 0.5–10 mg/L, for rifampicin 0.75–30 mg/L, for ethambutol 0.25–10 mg/L and for pyrazinamide 4–80 mg/L. The lower limit of quantification was 0.5 mg/L, 0.75 mg/L, 0.25 mg/L and 4.0 mg/L, respectively. Precision estimated by the coefficient of variation was <15% for all four drugs. The LC‐MS/MS method can readily be used for simultaneous quantification of first‐line anti‐TB drugs in plasma and is well suited for TDM. 相似文献
63.
Steffen Eickhardt Peter Braendstrup Erik Clasen‐Linde Karl E. Jensen Morten Alhede Thomas Bjarnsholt Niels Høiby Lars Vindeløv Claus Moser 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2013,121(5):456-459
Post‐transplant infections in allogeneic haematopoietic cell transplant (allo‐HCT) recipients often have severe consequences. This is especially the case when dealing with zygomycete infections where the result is often fatal. A major problem when dealing with zygomycete infections is the need for an accurate and fast diagnosis as the phylum is highly resistant towards the conventional antifungals. We herein describe a non‐fatal case of Lichtheimia corymbifera infection in an allo‐HCT recipient. 相似文献
64.
65.
Effect of resveratrol on experimental non‐alcoholic fatty liver disease depends on severity of pathology and timing of treatment
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66.
Gijs I. T. Iordens Esther M. M. Van Lieshout Bernd C. Van Es Niels W. L. Schep Roelf S. Breederveld Peter Patka Dennis Den Hartog 《Strategies in trauma and limb reconstruction (Online)》2013,8(3):141-147
Most recent studies on procedures for stabilizing the glenohumeral joint focus on arthroscopic techniques. A relatively simple open procedure is the modified Putti-Platt procedure. The aim of these retrospective case series was to evaluate the functional outcome, patient satisfaction, and quality of life of patients who underwent this procedure. After a median follow-up time of 4.7 (P25–P75 1.7–6.8) years, fifty-one patients could be enrolled with a mean age of 25 (21–39) years. Five patients (10 %) reported re-dislocations. The median Constant score for the affected side was 84 (P25–P75 75–91). Median loss of motion in abduction, elevation, external rotation, and external rotation in 90° of abduction did not exceed 10° when compared to the healthy shoulder. A median Rowe score of 92 (P25–P75 75–95) was measured. The WOSI score and SF-36 showed excellent quality of life. The VAS proved high patient satisfaction with the outcome; 7.9 (6.8–9.5). We concluded that the modified Putti-Platt procedure leads to excellent outcome scores and only marginal restriction in range of motion combined with a high patient satisfaction. Our data prove that excellent results can be obtained with a relatively simple open procedure. 相似文献
67.
Linda Juel Ahrenfeldt Sören Möller Karen Andersen-Ranberg Astrid Roll Vitved Rune Lindahl-Jacobsen Niels Christian Hvidt 《European journal of epidemiology》2017,32(10):921-929
Recent research suggests that epidemiological forces in religion and health can have opposed effects. Using longitudinal data of people aged 50+ included in wave 1 (2004–2005) of the Survey of Health, Ageing and Retirement in Europe (SHARE), and followed up through waves 2 (2006–2007), 4 (2011) and 5 (2013), we examined two forms of religious internalization and their association with health. Multivariate logistic regressions were used to examine all associations. Taking part in a religious organization was associated with lower odds of GALI (global activity limitation index) (OR = 0.86, 95% CI 0.75, 0.98) and depressive symptoms 0.80 (95% CI 0.69, 0.93), whereas being religiously educated lowered odds of poor self-rated health (SRH) 0.81 (95% CI 0.70, 0.93) and long-term health problems 0.84 (95% CI 0.74, 0.95). The more religious had lower odds of limitations with activities of daily living 0.76 (95% CI 0.58, 0.99) and depressive symptoms 0.77 (95% CI 0.64, 0.92) than other respondents, and compared to people who only prayed and did not have organizational involvement, they had lower odds of poor SRH 0.71 (95% CI 0.52, 0.97) and depressive symptoms 0.66 (95% CI 0.50, 0.87). Conversely, people who only prayed had higher odds of depressive symptoms than non-religious people 1.46 (95% CI 1.15, 1.86). Our findings suggest two types of religiousness: 1. Restful religiousness (praying, taking part in a religious organization and being religiously educated), which is associated with good health, and 2. Crisis religiousness (praying without other religious activities), which is associated with poor health. 相似文献
68.
Hua Qin Brendan T Keenan Diego R Mazzotti Fernando Vaquerizo-Villar Jan F Kraemer Niels Wessel Sergio Tufik Lia Bittencourt Peter A Cistulli Philip de Chazal Kate Sutherland Bhajan Singh Allan I Pack Ning-Hung Chen Ingo Fietze Thorarinn Gislason Steven Holfinger Ulysses J Magalang Thomas Penzel 《Sleep》2021,44(5)
Study ObjectivesPatients with obstructive sleep apnea (OSA) exhibit heterogeneous heart rate variability (HRV) during wakefulness and sleep. We investigated the influence of OSA severity on HRV parameters during wakefulness in a large international clinical sample.Methods1247 subjects (426 without OSA and 821 patients with OSA) were enrolled from the Sleep Apnea Global Interdisciplinary Consortium. HRV parameters were calculated during a 5-minute wakefulness period with spontaneous breathing prior to the sleep study, using time-domain, frequency-domain and nonlinear methods. Differences in HRV were evaluated among groups using analysis of covariance, controlling for relevant covariates.ResultsPatients with OSA showed significantly lower time-domain variations and less complexity of heartbeats compared to individuals without OSA. Those with severe OSA had remarkably reduced HRV compared to all other groups. Compared to non-OSA patients, those with severe OSA had lower HRV based on SDNN (adjusted mean: 37.4 vs. 46.2 ms; p < 0.0001), RMSSD (21.5 vs. 27.9 ms; p < 0.0001), ShanEn (1.83 vs. 2.01; p < 0.0001), and Forbword (36.7 vs. 33.0; p = 0.0001). While no differences were found in frequency-domain measures overall, among obese patients there was a shift to sympathetic dominance in severe OSA, with a higher LF/HF ratio compared to obese non-OSA patients (4.2 vs. 2.7; p = 0.009).ConclusionsTime-domain and nonlinear HRV measures during wakefulness are associated with OSA severity, with severe patients having remarkably reduced and less complex HRV. Frequency-domain measures show a shift to sympathetic dominance only in obese OSA patients. Thus, HRV during wakefulness could provide additional information about cardiovascular physiology in OSA patients.Clinical Trial Information: A Prospective Observational Cohort to Study the Genetics of Obstructive Sleep Apnea and Associated Co-Morbidities (German Clinical Trials Register - DKRS, DRKS00003966) https://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00003966 相似文献
69.
Rasmus Blechingberg Friis Niels Henrik Hjøllund Helle Pappot Gry Assam Taarnhøj Jesper Medom Vestergaard Halla Skuladottir 《Clinical lung cancer》2021,22(2):e169-e179
BackgroundPatient-reported outcome (PRO) measures have been increasingly implemented in routine care to aid in clinical decision-making. However, the prognostic value of PRO measures as a tool for decision making is not easily interpreted by clinicians. Our aims were to explore the prognostic value of PRO measures at disease progression and the changes in PRO measures between treatment start (baseline) and disease progression.Patients and MethodsSince 2014, patients with lung cancer have completed an electronic version of the European Organization for Research and Treatment of Cancer Quality of Life Questionnaires C30 and LC-13 before every outpatient visit at the Department of Oncology, Hospital Unit West, Jutland, Denmark. The patients’ responses were used in routine care. Patients receiving palliative antineoplastic treatment were eligible for analysis if the questionnaire had been completed at the initiation of first-line treatment and at disease progression. The prognostic value of the scores was evaluated using a Cox proportional hazard model. A P value < .01 was considered statistically significant.ResultsA total of 94 screened patients were included. At disease progression, survival could be predicted from the absolute score of the global health scale, 3 functional scales (physical, role, emotional), and 7 symptom scales (fatigue, pain, dyspnea, hemoptysis, lung cancer dyspnea, chest pain). In addition, changes in hemoptysis, dysphagia, dyspnea, and chest pain predicted for survival at progression.ConclusionPRO measures used in routine care can provide clinicians with relevant prognostic information about patients with lung cancer at disease progression. These results show the potential value of PRO measures when used in clinical decision-making. 相似文献
70.