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101.
A. VIK E. B. MATHIESEN J. BROX T. WILSGAARD I. NJØLSTAD L. JØRGENSEN J.‐B. HANSEN 《Journal of thrombosis and haemostasis》2011,9(4):638-644
Summary. Background: Osteoprotegerin (OPG) concentration in serum is associated with the presence and severity of atherosclerosis. Objective: To investigate the association between serum osteoprotegerin and the risk of a future myocardial infarction, ischemic stroke and mortality in a general population. Patients/methods: OPG was measured in serum collected from 6265 subjects recruited from a general population without a prior myocardial infarction and ischemic stroke (the Tromsø Study). Incident myocardial infarction, ischemic stroke and mortality were registered during follow‐up. Cox regression models were used to estimate crude and adjusted hazard ratios and 95% confidence intervals (HR; 95% CI). Results: There were 575 myocardial infarctions, 284 ischemic strokes and 824 deaths (146 deaths as a result of ischemic heart disease, 78 deaths because of stroke and 600 deaths due to other causes) in the cohort during a median of 10.6 years of follow‐up. Serum OPG (per SD [1.13 ng mL?1] increase in OPG) was associated with an increased risk of a myocardial infarction (1.20; 1.11–1.31), ischemic stroke (1.32; 1.18–1.47), total mortality (1.34; 1.26–1.42), death because of ischemic heart disease, (1.35; 1.18–1.54), stroke (1.44; 1.19–1.75) and non‐vascular causes (1.31; 1.22–1.41) after adjustment for age, gender, current smoking, systolic blood pressure, body mass index, high density lipoprotein cholesterol, total cholesterol, creatinine, high sensitivity C‐reactive protein (CRP) and diabetes mellitus or HbA1c > 6.1%. No association was detected between OPG and incident hemorrhagic stroke (1.02; 0.73–1.43). Conclusions: Serum OPG was associated with future risk of myocardial infarction, ischemic stroke, total mortality, mortality of ischemic heart disease, stroke and of non‐vascular causes independent of traditional cardiovascular risk factors. 相似文献
102.
A recent prospective clinical trial provides further evidence that breast cancers arising in germline BRCA1 mutation carriers are highly sensitive to cisplatin chemotherapy. The potential significance of these data for the management of patients with BRCA1-related and BRCA2-related breast cancer is discussed.In a previous issue of Breast Cancer Research Tomasz Byrski and colleagues present the results of a prospective phase II study of cisplatin in BRCA1-related metastatic breast cancer - that is, breast cancer arising in women with a germline mutation in BRCA1 [1]. They report evidence of substantial efficacy with an overall response rate of 80%, including 45% with complete response, and a time to progression of 12 months. The majority of patients in the study had triple receptor-negative breast cancer, and this time to progression compares favorably with median progression-free survival for triple receptor-negative breast cancer in contemporary series [2]. This study follows on from a retrospective study by the same group that reported a pathological complete response rate of 83% with neoadjuvant cisplatin chemotherapy, compared with a rate of 15% with nonrandomized comparator neoadjuvant chemotherapy [3].The molecular basis for these high response rates is well understood. Both BRCA1 and BRCA2 are required for DNA double-strand break repair by homologous recombination (HR-based DNA repair) [4,5]. Mutations in BRCA1 and BRCA2 inactivate protein function, and in cancer the wild-type allele is almost invariably lost, leading to a defect in HR-based DNA repair in the cancer. Platinum chemotherapy generates interstrand cross-links that can only be adequately repaired by HR-based DNA repair, and consequently BRCA1-deficient and BRCA2-deficient cells are highly sensitive to platinum chemotherapy both in vitro and in vivo. With high response rates in a prospective clinical trial, and a strong biological rationale, it is time to ask whether we are moving towards a new chemotherapy standard for BRCA1-related, and potentially by inference BRCA2-related, breast cancer or whether we need more evidence.The main strength of the current study is that it has been carried out at all. BRCA1 mutations account for a small proportion of patients with advanced breast cancer, even in countries with founder mutations, and this presents a substantial barrier to running studies testing standard chemotherapy. Use of the chemotherapy regimen outside the trial, and the wide availability of novel therapy trials competing for the same patients, add to the challenges of recruiting such trials. Nevertheless, the study by Byrski and colleagues is an open-label single-arm study of only 20 patients, with no central radiological confirmation of response rates, and both this study design and this size make a meaningful interpretation of progression-free survival very difficult. The study was in addition not prospectively registered in a clinical trial registry, removing one of the safeguards against publication bias.The study is dominated by women with three specific mutations in BRCA1 that represent the three founder mutations found in the Polish population [1], with over one-half being the single mutation 5382insC. One of these mutations, C61G, is predicted not to sensitize to cisplatin on the basis of preclinical data [6] yet cancers with this mutation appear to be just as sensitive to cisplatin in the study [1], a discrepancy for which it is important to understand the basis. Prior studies reported by this group have also been drawn from the Polish founder mutations, and we have limited data on the response of cancers with other BRCA1 mutations, and very limited data for BRCA2 mutations.Although the data for BRCA1/2-related breast are therefore relatively limited, there are substantial data on the sensitivity of BRCA1-related and BRCA2-related ovarian cancers to platinum-based chemotherapy [7,8]. BRCA1/2-related serous ovarian cancers are highly sensitive to platinum chemotherapy, and remain sensitive to repeat challenges with platinum chemotherapy, which likely explains the improved survival of BRCA1/2-related serous ovarian cancer compared with BRCA1/2 wild-type serous ovarian cancer [8].Should the accumulation of data, which includes this study by Byrski and colleagues, alter our approach to the treatment of BRCA1-related and BRCA2-related breast cancer? For patients with metastatic BRCA1-related breast cancer, although the data are limited, it seems clear that these patients should be offered the option of platinum-containing chemotherapy at some point during their treatment course. Whether platinum chemotherapy should be used as the first line in preference to other chemotherapy agents is unclear, and this is the subject of the BRCA trial (, NCT00321633) that randomizes first-line patients between carboplatin and docetaxel. For those with BRCA1 mutation-associated triple receptor-negative breast cancer and anthracycline-resistant and taxane-resistant disease, where there are few available active therapies, and the option of platinum-agent chemotherapy seems well founded.Whether the platinum agent should be cisplatin or whether carboplatin would have a similar response rate is unknown. Any difference in efficacy between the two drugs is likely to be small and may be outweighed by logistical and toxicity advantages for the patient. Whether patients with evidence of disease response and a long platinum-free interval (>6 months off chemotherapy) should be retreated with platinum-based chemotherapy on progression or whether they should be treated with alternative chemotherapy regimens remains unclear, and we await data to guide such decisions. Although there are few direct data on BRCA2-related breast cancer, the strength of the biological rational, the comparative data between BRCA1 and BRCA2 in ovarian cancer, and the evidence of poly(ADP ribose) polymerase (PARP) inhibitor efficacy in BRCA2-related breast cancer [ NCT005327279] all suggest that similar advice should apply to BRCA2-related breast cancer.What about the curative setting and patients receiving adjuvant or neoadjuvant chemotherapy? Here the data are less robust. Standard adjuvant anthracycline/taxane chemotherapy cures a substantial proportion of women with breast cancer, with evidence of better outcomes and therapy responses in the BRCA1/2 carrier population [10,11], so changes to this standard should only be made on the basis of strong evidence. At present the data to support platinum agents in this context are limited to retrospective analysis [3] or to prospective data for a very small number of patients [12]. Prospective studies are still required before routine practice changes in the curative setting. The one current exception to this is in the treatment of HER2-positive breast cancer in BRCA1/2 carriers. Relative equipoise has already been shown in the general breast cancer population for the TCH (docetaxel, carboplatin, trastuzumab) regimen compared with standard anthracycline-taxane-trastuzumab-based chemotherapy [13], and the TCH (docetaxel, carboplatin, trastuzumab) regimen presents an attractive option for BRCA1/2 carriers with HER2-positive breast cancer.PARP inhibitors target the same HR-based DNA repair defect as cisplatin chemotherapy, and there is evidence of efficacy for the PARP inhibitor olaparib in BRCA1-related and BRCA2-related breast cancer with substantial prior chemotherapy exposure [9]. PARP inhibitors target the DNA repair defect in a more specific fashion and are well tolerated without typical chemotherapy side effects [9]. The challenge in BRCA1/2-related advanced breast cancer is to develop and support a collaborative mechanism where patients can be identified and entered into randomized trials that test novel therapies such as PARP inhibitors, or mechanistically based chemotherapy, to robustly assess the efficacy relative to standard care, and therefore allow these patients to benefit from these BRCA1/2-focused treatments. 相似文献
103.
104.
105.
Arian Mashhood BS Radha Railkar PhD Takeshi Yokoo MD PhD Yakir Levin MD PhD Lisa Clark MPH PhD Sabrina Fox‐Bosetti BA Michael S. Middleton MD PhD Jonathan Riek PhD Eunkyung Kauh MD PhD Bernard J. Dardzinski PhD Donald Williams PhD Claude Sirlin MD Norah J. Shire PhD MPH 《Journal of magnetic resonance imaging : JMRI》2013,37(6):1359-1370
Purpose:
To evaluate the reproducibility of magnetic resonance imaging (MRI)‐determined hepatic fat fraction (%) across imaging sites with different magnet types and field strength. Reproducibility among MRI platforms is unclear, even though evaluating hepatic fat fractions (FFs) using MRI‐based methods is accurate against MR spectroscopy.Materials and Methods:
Overweight subjects were recruited to undergo eight MRI examinations at five imaging centers with a range of magnet manufacturers and field strengths (1.5 and 3 T). FFs were estimated in liver and in fat‐emulsion phantoms using three methods: 1) dual‐echo images without correction (nominally out‐of‐phase [OP] and in‐phase [IP]); 2) dual‐dual‐echo images (two sequences) with T2* correction (nominally OP/IP and IP/IP); and 3) six‐echo images with spectral model and T2* correction, at sequential alternating OP and IP echo times (Methods 1, 2, and 3, respectively).Results:
Ten subjects were recruited. For Methods 1, 2, and 3, respectively, hepatic FF ranged from ?2.5 to 27.0, 1.9 to 29.6, and 1.3 to 34.4%. Intraclass correlation coefficients were 0.85, 0.89, and 0.91 for each method, and within‐subject coefficients of variation were 18.5, 9.9, and 10.3%, respectively. Mean phantom FFs derived by Methods 2 and 3 were comparable to the known FF for each phantom. Method 1 underestimated phantom FF.Conclusion:
Methods 2 and 3 accurately assess FF. Strong reproducibility across magnet type and strength render them suitable for use in multicenter trials and longitudinal assessments. J. Magn. Reson. Imaging 2013;37:1359–1370. © 2012 Wiley Periodicals, Inc.106.
Objectives:
To evaluate the usefulness of the Forrest classification and the complete Rockall score with customary cut-off values for assessing the risk of adverse events in patients with upper gastrointestinal bleeding (UGI-B) subject to after-hours emergency oesophago-gastro-duodenoscopy (E-EGD) within six hours after admission.Methods:
The medical records of patients with non-variceal UGI-B proven by after-hours endoscopy were analysed. For ''high risk'' situations (Forrest stage Ia–IIb/complete Rockall score > 2), univariate analysis was conducted to evaluate odds ratio for reaching the study endpoints (30-day and one-year mortality, re-bleeding, hospital stay ≥ 3 days).Results:
During the study period (75 months), 86 cases (85 patients) met the inclusion criteria. Patients ''age was 66.36 ± 14.38 years; 60.5% were male. Mean duration of hospital stay was 15.21 ± 19.24 days. Mortality rate was 16.7% (30 days) and 32.9% (one year); 14% of patients re-bled. Univariate analysis of post-endoscopic Rockall score ≥ 2 showed an odds ratio of 6.09 for death within 30 days (p = 0.04). No other significant correlations were found.Conclusion:
In patients with UGI-B subject to after-hours endoscopy, a ''high-risk'' Rockall score permits an estimation of the risk of death within 30 days but not of re-bleeding. A ''high-risk '' Forrest score is not significantly associated with the study endpoints. 相似文献107.
108.
KM Kanal NJ Hangiandreou AM Sykes HE Eklund PA Araoz JA Leon BJ Erickson 《Journal of digital imaging》2001,14(1):30-37
The aims of this work were to measure the accuracy of one continuous speech recognition product and dependence on the speaker's gender and status as a native or nonnative English speaker, and evaluate the product's potential for routine use in transcribing radiology reports. IBM MedSpeak/Radiology software, version 1.1 was evaluated by 6 speakers. Two were nonnative English speakers, and 3 were men. Each speaker dictated a set of 12 reports. The reports included neurologic and body imaging examinations performed with 6 different modalities. The dictated and original report texts were compared, and error rates for overall, significant, and subtle significant errors were computed. Error rate dependence on modality, native English speaker status, and gender were evaluated by performing ttests. The overall error rate was 10.3 +/- 3.3%. No difference in accuracy between men and women was found; however, significant differences were seen for overall and significant errors when comparing native and nonnative English speakers (P = .009 and P = .008, respectively). The speech recognition software is approximately 90% accurate, and while practical implementation issues (rather than accuracy) currently limit routine use of this product throughout a radiology practice, application in niche areas such as the emergency room currently is being pursued. This methodology provides a convenient way to compare the initial accuracy of different speech recognition products, and changes in accuracy over time, in a detailed and sensitive manner. 相似文献
109.
Dipika V Patel PhD MRCOphth Charles NJ McGhee PhD FRCOphth 《Clinical & experimental ophthalmology》2009,37(2):232-238
There has been a significant increase in the number of reported cases of Acanthamoeba keratitis reported internationally over the last 24 months. Diagnosing Acanthamoeba keratitis is often difficult and part of the difficulty is attributed to the variability of presentation. This article provides a comprehensive photographic reference of common and uncommon clinical signs of Acanthamoeba keratitis. 相似文献
110.
Workie DW Graham TB Laor T Rajagopal A O'Brien KJ Bommer WA Racadio JM Shire NJ Dardzinski BJ 《Pediatric radiology》2007,37(6):535-543
Background The development of a quantifiable and noninvasive method of monitoring disease activity and response to therapy is vital for
arthritis management.
Objective The purpose of this study was to investigate the utility of quantitative dynamic contrast-enhanced MRI (DCE-MRI) based on
pharmacokinetic (PK) modeling to evaluate disease activity in the knee and correlate the results with the clinical assessment
in children with juvenile idiopathic arthritis (JIA).
Materials and methods A group of 17 children with JIA underwent longitudinal clinical and laboratory assessment and DCE-MRI of the knee at enrollment,
3 months, and 12 months. A PK model was employed using MRI signal enhancement data to give three parameters, Ktrans
′ (min−1), kep (min−1), and Vp
′ and to calculate synovial volume.
Results The PK parameters, synovial volumes, and clinical and laboratory assessments in most children were significantly decreased
(P < 0.05) at 12 months when compared to the enrollment values. There was excellent correlation between the PK and synovial
volume and the clinical and laboratory assessments. Differences in MR and clinical parameter values in individual subjects
illustrate persistent synovitis when in clinical remission.
Conclusion A decrease in PK parameter values obtained from DCE-MRI in children with JIA likely reflects diminution of disease activity.
This technique may be used as an objective follow-up measure of therapeutic efficacy in patients with JIA. MR imaging can
detect persistent synovitis in patients considered to be in clinical remission. 相似文献