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31.
Stage migration in breast cancer: surgical decisions concerning isolated tumour cells and micro-metastases in the sentinel lymph node. 总被引:3,自引:0,他引:3
Louise de Widt-Levert Vivianne Tjan-Heijnen Peter Bult Theo Ruers Theo Wobbes 《European journal of surgical oncology》2003,29(3):216-220
AIMS: Sentinel lymph node biopsy has replaced the axillary lymph node dissection (ALND) in primary surgery for breast cancer in many hospitals and is expected to become the standard of care in due time. Since the sentinel lymph node is subjected to more extensive pathologic examination than the lymph nodes in the axillary dissection specimen, more patients are found to be node positive (N+); however many of them contain micro-metastases (相似文献
32.
Krabbe Paul F.M. Peerenboom Lonneke Langenhoff Barbara S. Ruers Theo J.M. 《Quality of life research》2004,13(7):1247-1253
Introduction: We investigated whether the sensitivity of the generic health-related quality of life (HRQoL) EQ-5D summary measure (or index) to detect changes over time in a clinical setting is comparable with that of a disease-specific HRQoL questionnaire. Methods: Patients with liver metastases (n = 75) filled out the five domains of the EQ-5D self-classifier, the EQ VAS, and the EORTC QLQ C-30 (a disease-specific (cancer) HRQoL questionnaire). The HRQoL instruments were completed before intervention, and 1/2 month and 3 and 6 months after intervention. Three analyses were performed. First, the EQ-5D index (based on self-classification) was compared to the EQ VAS. Second, the EQ-5D domains were compared to corresponding EORTC QLQ C-30 scales. Third, EQ-5D index and EQ VAS were compared with the EORTC QLQ C-30 global health-status scale. Effect size was chosen as the metric of responsiveness. Results: The EQ-5D index was slightly less responsive than the EQ VAS. Overall, the responsiveness of the EQ-5D index and EQ VAS was equal to the EORTC QLQ C-30 global health-status scale. Conclusion: Despite its generic principle and the apparent crudeness of its framework, the responsiveness of the EQ-5D proved to be comparable to that of a disease-specific HRQoL questionnaire in this specific clinical setting. 相似文献
33.
Harald J J Moonen Edwin J C Moonen Lou Maas Jan W Dallinga Jos C S Kleinjans Theo M C M de Kok 《Food and chemical toxicology》2004,42(6):869-878
2-Amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) is a mutagenic and carcinogenic heterocyclic amine formed during ordinary cooking, and is subsequently metabolically activated by cytochrome P4501A2 (CYP1A2) and N-acetyltransferase 2 (NAT2). Respective genes encoding for these enzymes, display polymorphic distribution in the human population and are thus believed to cause interindividual differences in cancer risk susceptibility. The present study investigated the influence of dietary exposure and CYP1A2 and NAT2 genotypes and phenotypes on differential urinary PhIP excretion levels in 71 human volunteers after consumption of either a high (7.4 ng/g) or low (1.7 ng/g) dose of PhIP. Urinary PhIP excretion levels were found to reflect recent dietary exposure levels, with average levels of 174% (high dose group) and 127% (low dose group), as compared to pre-feed levels. Urinary caffeine metabolite ratios were significantly different between the two NAT2 genotypes, whereas for CYP1A2, the apparent difference in metabolic ratios between the genotypes was statistically non-significant. Significant correlations were firstly found between the CYP1A2-164A-->C (CYP1A2*1F) polymorphism and differential urinary PhIP excretion levels. Although the found correlations are driven primarily by a small number of subjects possessing the homozygous variant constellation, the strong influence of this genotype indicates that the CYP1A2*1F polymorphism could play an important role in human cancer risk susceptibility. 相似文献
34.
The impact of geographic unit of analysis on socioeconomic inequalities in cancer survival and distant summary stage – a population‐based study 下载免费PDF全文
Hanna E. Tervonen Stephen Morrell Sanchia Aranda David Roder Hui You Theo Niyonsenga Richard Walton Deborah Baker David Currow 《Australian and New Zealand journal of public health》2017,41(2):130-136
Objective: When using area‐level disadvantage measures, size of geographic unit can have major effects on recorded socioeconomic cancer disparities. This study examined the extent of changes in recorded socioeconomic inequalities in cancer survival and distant stage when the measure of socioeconomic disadvantage was based on smaller Census Collection Districts (CDs) instead of Statistical Local Areas (SLAs). Methods: Population‐based New South Wales Cancer Registry data were used to identify cases diagnosed with primary invasive cancer in 2000–2008 (n=264,236). Logistic regression and competing risk regression modelling were performed to examine socioeconomic differences in odds of distant stage and hazard of cancer death for all sites combined and separately for breast, prostate, colorectal and lung cancers. Results: For all sites collectively, associations between socioeconomic disadvantage and cancer survival and distant stage were stronger when the CD‐based socioeconomic disadvantage measure was used compared with the SLA‐based measure. The CD‐based measure showed a more consistent socioeconomic gradient with a linear upward trend of risk of cancer death/distant stage with increasing socioeconomic disadvantage. Site‐specific analyses provided similar findings for the risk of death but less consistent results for the likelihood of distant stage. Conclusions: The use of socioeconomic disadvantage measure based on the smallest available spatial unit should be encouraged in the future. Implications for public health: Disadvantage measures based on small spatial units can more accurately identify socioeconomic cancer disparities to inform priority settings in service planning. 相似文献
35.
Sehar Sajid Mohammed Gulrez Zariwala Richard Mackenzie Mark Turner Theo Nell Srikanth Bellary Derek Renshaw 《Nutrients》2022,14(11)
Obesity is a multifactorial disease and is associated with an increased risk of developing metabolic syndrome and co-morbidities. Dysregulated expansion of the adipose tissue during obesity induces local tissue hypoxia, altered secretory profile of adipokines, cytokines and chemokines, altered profile of local tissue inflammatory cells leading to the development of low-grade chronic inflammation. Low grade chronic inflammation is considered to be the underlying mechanism that increases the risk of developing obesity associated comorbidities. The glucocorticoid induced protein annexin A1 and its N-terminal peptides are anti-inflammatory mediators involved in resolving inflammation. The aim of the current study was to investigate the role of annexin A1 in obesity and associated inflammation. To achieve this aim, the current study analysed data from two feasibility studies in clinical populations: (1) bariatric surgery patients (Pre- and 3 months post-surgery) and (2) Lipodystrophy patients. Plasma annexin A1 levels were increased at 3-months post-surgery compared to pre-surgery (1.2 ± 0.1 ng/mL, n = 19 vs. 1.6 ± 0.1 ng/mL, n = 9, p = 0.009) and positively correlated with adiponectin (p = 0.009, r = 0.468, n = 25). Plasma annexin A1 levels were decreased in patients with lipodystrophy compared to BMI matched controls (0.2 ± 0.1 ng/mL, n = 9 vs. 0.97 ± 0.1 ng/mL, n = 30, p = 0.008), whereas CRP levels were significantly elevated (3.3 ± 1.0 µg/mL, n = 9 vs. 1.4 ± 0.3 µg/mL, n = 31, p = 0.0074). The roles of annexin A1 were explored using an in vitro cell based model (SGBS cells) mimicking the inflammatory status that is observed in obesity. Acute treatment with the annexin A1 N-terminal peptide, AC2-26 differentially regulated gene expression (including PPARA (2.8 ± 0.7-fold, p = 0.0303, n = 3), ADIPOQ (2.0 ± 0.3-fold, p = 0.0073, n = 3), LEP (0.6 ± 0.2-fold, p = 0.0400, n = 3), NAMPT (0.4 ± 0.1-fold, p = 0.0039, n = 3) and RETN (0.1 ± 0.03-fold, p < 0.0001, n = 3) in mature obesogenic adipocytes indicating that annexin A1 may play a protective role in obesity and inflammation. However, this effect may be overshadowed by the continued increase in systemic inflammation associated with rapid tissue expansion in obesity. 相似文献
36.
Neurotrophins regulate survival, neurite outgrowth, and phenotypic maturation of developing neurons. Brain-derived neurotrophic factor (BDNF) can promote the survival of developing cholinergic forebrain neurons in vitro and reduce their degeneration following injury in adult rats. We investigated the role of endogenous BDNF during postnatal development of these cholinergic neurons by analyzing homozygous BDNF-deficient (−/−) mice and their littermates (+/+, +/−). At P6, the number of choline acetyltransferase- (ChAT) positive neurons in the medial septum was 23% lower in BDNF−/− mice, although their brain and body weight was normal. At P15, control (+/+) littermates had 45% more and 45% larger ChAT-positive neurons and a much denser cholinergic hippocampal innervation than at P6, indicative of maturation of the septohippocampal system. In BDNF−/− mice, the number, size, and ChAT-immunostaining intensity of the cholinergic neurons remained the same between P6 and P15 (few mice survive longer). BDNF−/− mice had about three times more TUNEL-labeled (a marker of apoptosis) cells in the medial septum at P6, consistent with (but not proof of) the possibility that the cholinergic neurons were dying. The cholinergic hippocampal innervation in BDNF−/− mice expanded to a lesser extent than in controls and had reduced levels of acetylcholinesterase staining at P15. The developmental deficits were largely similar in the neostriatum of BDNF−/− mice. These findings suggest that BDNF is critical for postnatal development and maturation of cholinergic forebrain neurons. 相似文献
37.
Geovana L. Santana Murilo C. Crovace Ernesto E. Mazn Adilson J. A. de Oliveira Theo Z. Pavan Edgar D. Zanotto 《Materials》2022,15(9)
Magnetic hyperthermia (MHT) is a therapy that uses the heat generated by a magnetic material for cancer treatment. Magnetite nanoparticles are the most used materials in MHT. However, magnetite has a high Curie temperature (Tc~580 °C), and its use may generate local superheating. To overcome this problem, strontium-doped lanthanum manganite could replace magnetite because it shows a Tc near the ideal range (42–45 °C). In this study, we developed a smart composite formed by an F18 bioactive glass matrix with different amounts of Lanthanum-Strontium Manganite (LSM) powder (5, 10, 20, and 30 wt.% LSM). The effect of LSM addition was analyzed in terms of sinterability, magnetic properties, heating ability under a magnetic field, and in vitro bioactivity. The saturation magnetization (Ms) and remanent magnetization (Mr) increased by the LSM content, the confinement of LSM particles within the bioactive glass matrix also caused an increase in Tc. Calorimetry evaluation revealed a temperature increase from 5 °C (composition LSM5) to 15 °C (LSM30). The specific absorption rates were also calculated. Bioactivity measurements demonstrated HCA formation on the surface of all the composites in up to 15 days. The best material reached 40 °C, demonstrating the proof of concept sought in this research. Therefore, these composites have great potential for bone cancer therapy and should be further explored. 相似文献
38.
Lentiviral shRNA silencing of murine bone marrow cell CCR2 leads to persistent knockdown of CCR2 function in vivo 下载免费PDF全文
Bot I Guo J Van Eck M Van Santbrink PJ Groot PH Hildebrand RB Seppen J Van Berkel TJ Biessen EA 《Blood》2005,106(4):1147-1153
A major barrier in hematopoietic gene function studies is posed by the laborious and time-consuming generation of knockout mice with an appropriate genetic background. Here we present a novel lentivirus-based strategy for the in situ generation of hematopoietic knockdowns. A short hairpin RNA (shRNA) was designed targeting murine CC-chemokine receptor 2 (CCR2), which was able to specifically blunt CCR2 expression at the mRNA, protein, and functional levels in vitro. Reconstitution of irradiated recipient mice with autologous bone marrow that had been ex vivo transduced with shRNA lentivirus led to persistent down-regulation of CCR2 expression, which translated into a 70% reduction in CCR2-dependent recruitment of macrophages to an inflamed peritoneal cavity without noticeable side effects on related chemokine receptors or general inflammation status. These findings clearly demonstrate the potential of shRNA lentivirus-infected bone marrow transplantation as a rapid and effective method to generate hematopoietic knockdowns for leukocyte gene function studies. 相似文献
39.
Wendy M. van der Deure Robin P. Peeters ré G. Uitterlinden†‡ Albert Hofman† Monique M. B. Breteler† Jacqueline Witteman† Theo J. Visser 《Clinical endocrinology》2009,71(1):137-144
Introduction Thyroid function and genetic variation in the hypothalamus–pituitary–thyroid axis have been implicated in blood pressure regulation and susceptibility to hypertension. However studies conducted thus far were small with controversial results.
Objective To examine whether serum thyroid parameters and polymorphisms in the type 2 deiodinase and the TSH receptor are associated with blood pressure and the presence of hypertension in two large cohorts of elderly subjects.
Design and participants We studied a random sample of 1444 subjects of the Rotterdam study, and 997 subjects of the Rotterdam Scan study, two population-based cohort studies among elderly individuals aged 55–90 years.
Outcome measurements Data on blood pressure and hypertension were obtained, and serum thyroid parameters, D2-Thr92Ala, D2-ORFa-Gly3Asp and TSHR-Asp727Glu polymorphisms were determined.
Results In contrast to previous findings, no consistent and/or significant associations were found between serum TSH and FT4 and blood pressure in both cohorts. In addition, the D2-Thr92Ala, D2-ORFa-Gly3Asp and TSHR-Asp727Glu polymorphisms were not associated with blood pressure or the risk of hypertension.
Conclusions In two large populations of elderly subjects, neither serum thyroid parameters nor polymorphisms in the type 2 deiodinase and the TSH receptor, were associated with blood pressure or the presence of hypertension. Our data suggest that thyroid function is not an important determinant of hypertension in elderly Dutch subjects. 相似文献
Objective To examine whether serum thyroid parameters and polymorphisms in the type 2 deiodinase and the TSH receptor are associated with blood pressure and the presence of hypertension in two large cohorts of elderly subjects.
Design and participants We studied a random sample of 1444 subjects of the Rotterdam study, and 997 subjects of the Rotterdam Scan study, two population-based cohort studies among elderly individuals aged 55–90 years.
Outcome measurements Data on blood pressure and hypertension were obtained, and serum thyroid parameters, D2-Thr92Ala, D2-ORFa-Gly3Asp and TSHR-Asp727Glu polymorphisms were determined.
Results In contrast to previous findings, no consistent and/or significant associations were found between serum TSH and FT4 and blood pressure in both cohorts. In addition, the D2-Thr92Ala, D2-ORFa-Gly3Asp and TSHR-Asp727Glu polymorphisms were not associated with blood pressure or the risk of hypertension.
Conclusions In two large populations of elderly subjects, neither serum thyroid parameters nor polymorphisms in the type 2 deiodinase and the TSH receptor, were associated with blood pressure or the presence of hypertension. Our data suggest that thyroid function is not an important determinant of hypertension in elderly Dutch subjects. 相似文献
40.
Schoofs MW van der Klift M Hofman A de Laet CE Herings RM Stijnen T Pols HA Stricker BH 《Annals of internal medicine》2003,139(6):476-482
Since most hip fractures are related to osteoporosis, treating accelerated bone loss can be an important strategy to prevent hip fractures. Thiazides have been associated with reduced age-related bone loss by decreasing urinary calcium excretion. 相似文献