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81.
Androgen receptor amplification is associated with increased cell proliferation in prostate cancer 总被引:4,自引:0,他引:4
Haapala K Kuukasjärvi T Hyytinen E Rantala I Helin HJ Koivisto PA 《Human pathology》2007,38(3):474-478
Mechanisms of prostate cancer progression during hormonal therapy and the pathobiologic consequences of androgen receptor (AR) gene amplification are inadequately known. To further investigate the hypothesis that AR gene amplification is associated with increased cell proliferation, we analyzed 123 paraffin-embedded prostate cancer specimens from men who experienced tumor relapse during androgen withdrawal therapy. We used fluorescence in situ hybridization to quantify AR gene copy number and Ki-67 immunohistochemistry to determine cell proliferation. One third of the tumors showed AR gene amplification. Among tumors with AR amplification, the mean cell proliferation rate was 19.8 (SD, 12.3; 95% confidence interval [CI], 15.4-24.1), whereas it was 13.0 (SD, 15.9; 95% CI, 9.1-16.8) in tumors without amplification (P = .032). In the best fitting logistic regression model, only proliferation remained significant (P = .040). When the median Ki-67 labeling index (6.7%) of all tumors was used as a cutoff point, the tumors with AR amplification were more frequently highly proliferating than tumors with no amplification (P = .010; odds ratio, 3.4; 95% CI, 1.4-8.3). Our results imply that progression of prostate cancer during androgen withdrawal therapy is associated with AR gene amplification and increased cell proliferation rate in one third of tumors. We suggest that AR gene amplification is an important molecular mechanism underlying the increase in proliferation rate of a substantial fraction of recurrent prostate carcinomas. However, efforts should be targeted to develop prostate cancer cell lines to study causal relationships between AR gene amplification and various biologic variables. 相似文献
82.
Vainiotalo S Riihimäki V Pekari K Teräväinen E Aitio A 《Journal of occupational and environmental hygiene》2007,4(10):739-750
Healthy male volunteers were exposed via inhalation to gasoline oxygenates methyl tert-butyl ether (MTBE) or tert-amyl methyl ether (TAME). The 4-hr exposures were carried out in a dynamic chamber at 25 and 75 ppm for MTBE and at 15 and 50 ppm for TAME. The overall mean pulmonary retention of MTBE was 43 +/- 2.6%; the corresponding mean for TAME was 51 +/- 3.9%. Approximately 52% of the absorbed dose of MTBE was exhaled within 44 hr following the exposure; for TAME, the corresponding figure was 30%. MTBE and TAME in blood and exhaled air reached their highest concentrations at the end of exposure, whereas the concentrations of the metabolites tert-butanol (TBA) and tert-amyl alcohol (TAA) concentrations were highest 0.5-1 hr after the exposure and then declined slowly. Two consecutive half-times were observed for the disappearance of MTBE and TAME from blood and exhaled air. The half-times for MTBE in blood were about 1.7 and 3.8 hr and those for TAME 1.2 and 4.9 hr. For TAA, a single half-time of about 6 hr best described the disappearance from blood and exhaled air; for TBA, the disappearance was slow and seemed to follow zero-order kinetics for 24 hr. In urine, maximal concentrations of MTBE and TAME were observed toward the end of exposure or slightly (< or = 1 hr) after the exposure and showed half-times of about 4 hr and 8 hr, respectively. Urinary concentrations of TAA followed first-order kinetics with a half-time of about 8 hr, whereas the disappearance of TBA was slower and showed zero-order kinetics at concentrations above approx. 10 micro mol/L. Approximately 0.2% of the inhaled dose of MTBE and 0.1% of the dose of TAME was excreted unchanged in urine, whereas the urinary excretion of free TBA and TAA was 1.2% and 0.3% within 48 hr. The blood/air and oil/blood partition coefficients, determined in vitro, were 20 and 14 for MTBE and 20 and 37 for TAME. By intrapolation from the two experimental exposure concentrations, biomonitoring action limits corresponding to an 8-hr time-weighted average (TWA) exposure of 50 ppm was estimated to be 20 micro mol/L for post-shift urinary MTBE, 1 mu mol/L for exhaled air MTBE in a post-shift sample, and 30 micro mol/L for urinary TBA in a next-morning specimen. For TAME and TAA, concentrations corresponding to an 8-hr TWA exposure at 20 ppm were estimated to be 6 micro mol/L (TAME in post-shift urine), 0.2 micro mol/L (TAME in post-shift exhaled air), and 3 micro mol/L (TAA in next morning urine). 相似文献
83.
The purpose of this study was to explore changes in family health associated with child's chronic illness and hospitalization. The aim was to answer the following questions: (i) What kind of changes do families experience when a child in the family is afflicted by a chronic illness; and (ii) What kind of changes do families experience when their child is admitted to hospital? The data were collected in 2002 in interviews with 29 such families whose children were receiving treatment or who had previously received treatment on the paediatric wards of two hospitals in Finland. Data were collected until reaching theoretical saturation, in which no additional data are found. Data analysis was based on the grounded theory method, proceeding to the stage of axial coding. Family health was formed out of two different dimensions: the constituent systems and the resources of family health. The constituent systems describe the impact of the child's chronic illness and period of hospitalization at the level of both individual family members and the family as a whole. These systems were described by five categories: (i) ill child at the centre of family attention, (ii) siblings in a minor role, (iii) the child's illness governs parental well‐being, (iv) the roller coaster of the couple relationship and (v) the whole family is ill. The resources promoting and maintaining family health were divided into six different categories: (i) creative and maintaining mental images, (ii) active involvement, (iii) internal coping means, (iv) reinforcement of coping means, (v) awareness and change of values and (vi) social network shares emotional burden and responsibility for care. The results of the study show that family health is highly vulnerable when a child has to be admitted to hospital because of a chronic condition. They should help nursing staff gain a clearer picture of the depth and diversity of family health and support the resources that promote family health. Future research should study the methods of family nursing used in the care of families with children with chronic conditions. 相似文献
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- THE PURPOSE OF THIS QUALITY improvement project was to determine patients' perceptions of the emotional support and information provided to their family members by nurses in a day surgery setting.
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- THE PROJECT WAS CONDUCTED in a day surgery unit of a hospital in western Finland. Data were collected from 60 participants using a questionnaire designed specifically for the project.
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- THE RESULTS SHOWED that half of the patients appreciated the presence of their family members during hospital care. The emotional support provided to family members was rated as moderate, and more than 50% of the patients believed their family members were adequately informed. The results were used to help develop tools for patient and family member education. AORN J 81 (May 2005) 1030-1039.
86.
Torbjrn Tomson Anthony Marson Paul Boon Maria Paola Canevini Athanasios Covanis Eija Gaily Reetta Klviinen Eugen Trinka 《Epilepsia》2015,56(7):1006-1019
This document provides guidance on the use of valproate in girls and women of childbearing age from a joint Task Force of the Commission on European Affairs of the International League Against Epilepsy (CEA‐ILAE) and the European Academy of Neurology (EAN), following strengthened warnings from the Coordination Group for Mutual Recognition and Decentralised Procedures‐Human (CMDh) of the European Medicines Agency (EMA), which highlight the risk of malformations and developmental problems in infants who are exposed to valproate in the womb. To produce these recommendations, the Task Force has considered teratogenic risks associated with use of valproate and treatment alternatives, the importance of seizure control and of patient and fetal risks with seizures, and the effectiveness of valproate and treatment alternatives in the treatment of different epilepsies. The Task Force's recommendations include the following: (1) Where possible, valproate should be avoided in women of childbearing potential. (2) The choice of treatment for girls and women of childbearing potential should be based on a shared decision between clinician and patient, and where appropriate, the patient's representatives. Discussions should include a careful risk–benefit assessment of reasonable treatment options for the patient's seizure or epilepsy type. (3) For seizure (or epilepsy) types where valproate is the most effective treatment, the risks and benefits of valproate and other treatment alternatives should be discussed. (4) Valproate should not be prescribed as a first‐line treatment for focal epilepsy. (5) Valproate may be offered as a first‐line treatment for epilepsy syndromes where it is the most effective treatment, including idiopathic (genetic) generalized syndromes associated with tonic–clonic seizures. (6) Valproate may be offered as a first‐line treatment in situations where pregnancy is highly unlikely (e.g., significant intellectual or physical disability). (7) Women and girls taking valproate require regular follow‐up for ongoing consideration of the most appropriate treatment regimen. 相似文献
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Xiangyu Deng Nikki Shariat Elizabeth M. Driebe Chandler C. Roe Beth Tolar Eija Trees Paul Keim Wei Zhang Edward G. Dudley Patricia I. Fields David M. Engelthaler 《Journal of clinical microbiology》2015,53(1):212-218
A retrospective investigation was performed to evaluate whole-genome sequencing as a benchmark for comparing molecular subtyping methods for Salmonella enterica serotype Enteritidis and survey the population structure of commonly encountered S. enterica serotype Enteritidis outbreak isolates in the United States. A total of 52 S. enterica serotype Enteritidis isolates representing 16 major outbreaks and three sporadic cases collected between 2001 and 2012 were sequenced and subjected to subtyping by four different methods: (i) whole-genome single-nucleotide-polymorphism typing (WGST), (ii) multiple-locus variable-number tandem-repeat (VNTR) analysis (MLVA), (iii) clustered regularly interspaced short palindromic repeats combined with multi-virulence-locus sequence typing (CRISPR-MVLST), and (iv) pulsed-field gel electrophoresis (PFGE). WGST resolved all outbreak clusters and provided useful robust phylogenetic inference results with high epidemiological correlation. While both MLVA and CRISPR-MVLST yielded higher discriminatory power than PFGE, MLVA outperformed the other methods in delineating outbreak clusters whereas CRISPR-MVLST showed the potential to trace major lineages and ecological origins of S. enterica serotype Enteritidis. Our results suggested that whole-genome sequencing makes a viable platform for the evaluation and benchmarking of molecular subtyping methods. 相似文献
90.