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1.

Background

Physicians treating nonvalvular atrial fibrillation (AF) assess stroke and bleeding risks when deciding on anticoagulation. The agreement between empirical and physician-estimated risks is unclear. Furthermore, the association between patient and physician sex and anticoagulation decision-making is uncertain.

Methods

We pooled data from 2 national primary care physician chart audit databases of patients with AF (Facilitating Review and Education to Optimize Stroke Prevention in Atrial Fibrillation and Coordinated National Network to Engage Physicians in the Care and Treatment of Patients with Atrial Fibrillation Chart Audit) with a combined 1035 physicians (133 female, 902 male) and 10,927 patients (4567 female and 6360 male).

Results

Male physicians underestimated stroke risk in female patients and overestimated risk in male patients. Female physicians estimated stroke risk well in female patients but underestimated the risk in male patients. Risk of bleeding was underestimated in all. Despite differences in risk assessment by physician and patient sex, > 90% of patients received anticoagulation across all subgroups. There was modest agreement between physician estimated and calculated (ie, CHADS2 score) stroke risk: Kappa scores were 0.41 (0.35-0.47) for female physicians and 0.34 (0.32-0.36) for male physicians.

Conclusions

Our study is the first to examine the association between patient and physician sex influences and stroke and bleeding risk estimation in AF. Although there were differences in agreement between physician estimated stroke risk and calculated CHADS2 scores, these differences were small and unlikely to affect clinical practice; further, despite any perceived differences in the accuracy of risk assessment by sex, most patients received anticoagulation.  相似文献   
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We obtained serum bone markers and other relevant endocrine assays on 5 patients with osteonecrosis of the jaw (ONJ). The assays were C-telopeptide, N-telopeptide, bone-specific alkaline phosphatase, osteocalcin, intact parathyroid hormone, T3, T4, TSH, and Vitamin D 25 hydroxy. Diagnostic criteria for ONJ were those formulated by the American Association of Oral and Maxillofacial Surgeons. Four of our patients were women. Two had metastatic breast cancer and had been treated with zoledronic acid; one had also received pamidronate. Two others had osteoporosis and had been treated with daily alendronate. One man had metastatic prostate cancer treated with zoledronic acid. All patients had been withdrawn from bisphosphonate for at least 6 months. None were taking or had taken corticosteroids. None of the lesions had shown any significant healing and all were still causing the patients considerable distress. Yet the bone markers were within the normal range as measured in our laboratory, except for intact parathyroid hormone, which was slightly elevated in one case of metastatic breast cancer (177 pg/mL). Because the jaws have a greater blood supply than other bones, and a high bone turnover rate, bisphosphonates are highly concentrated in the jaws. This anatomic concentration of bisphosphonates might cause bisphosphonate-osteonecrosis to be manifested exclusively in the jaws and is consistent with our finding of normal serum bone markers in ONJ patients.  相似文献   
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Introduction

Platelets are involved in regeneration at sites of pathology, apart from their role in clotting. A preparation composed mainly of platelets (platelet-rich plasma gel) applied to sites of bony pathology, after surgical treatment of lesions, may hasten bone regeneration.

Materials and methods

An autologous platelet-rich plasma (PRP) gel was prepared using a standardized technique, without using thrombin clot accelerator, and applied to surgical site in six patients of study group. Five patients were enrolled as controls, in whom PRP gel was not used. The differences in the occurrence of radiographic changes between the study and control group at 6, 12, 18 and 24 weeks after surgery were analysed with chi-square test. Intragroup radiographic changes, i.e. within the study and control groups occurring over the 24 weeks of follow-up, were analysed with Friedman test.

Results

A trend towards more rapid healing was observed in the study group at 6, 12, 18 and 24 weeks. However, these differences between the study and control group were not statistically significant. Both the study and control group demonstrated significant healing changes over the 24 weeks of follow-up.

Conclusions

It is possible to prepare platelet-rich plasma gel without using thrombin clot accelerator. PRP, as prepared and applied to surgical sites in this study, was not observed to significantly enhance bone regeneration. All surgical sites, both in the PRP and control group, showed significant healing changes over 6 months.  相似文献   
8.

Background.

nab-Paclitaxel in combination with gemcitabine has emerged as a new treatment option for patients with metastatic pancreatic cancer (MPC), based on superiority over gemcitabine demonstrated in the phase III MPACT trial. Previously, Karnofsky performance status (KPS) score and the presence of liver metastases were shown to be predictive of survival with nab-paclitaxel plus gemcitabine treatment. This analysis sought to further explore the relationship between clinical characteristics and survival in the MPACT trial and to identify potential predictors of overall survival and progression-free survival in patients with MPC.

Materials and Methods.

Cox regression models adjusted for stratification factors and a stepwise multivariate analysis of prespecified baseline prognostic factors were performed.

Results.

Treatment effect was significantly associated with survival, with a similar magnitude of reduction in risk of death compared with the previously reported primary analysis. Treatment effect consistently favored nab-paclitaxel plus gemcitabine across the majority of the prespecified factors. In addition to KPS score and presence of liver metastases, age and number of metastatic sites were independent prognostic factors of overall and progression-free survival. Baseline carbohydrate antigen 19-9 was not found to be an independent prognostic factor of survival in this analysis.

Conclusion.

The results of this analysis confirm broad utility of nab-paclitaxel plus gemcitabine for the treatment of MPC. In addition, these findings suggest that KPS score, presence of liver metastases, age, and number of metastatic sites are important predictors of survival that may be useful when making treatment decisions and designing future clinical trials.  相似文献   
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We used DNA content flow cytometry followed by oligonucleotide array based comparative genomic hybridization to survey the genomes of 326 tumors, including 41 untreated surgically resected triple negative breast cancers (TNBC). A high level (log2ratio ≥1) 9p24 amplicon was found in TNBC (12/41), glioblastomas (2/44), and colon carcinomas (2/68). The shortest region of overlap for the amplicon targets 9p24.1 and includes the loci for PD-L1, PD-L2, and JAK2 (PDJ amplicon). In contrast this amplicon was absent in ER+ (0/8) and HER2+ (0/15) breast tumors, and in pancreatic ductal adenocarcinomas (0/150). The PDJ amplicon in TNBCs was correlated with clinical outcomes in group comparisons by two-sample t-tests for continuous variables and chi-squared tests for categorical variables. TNBC patients with the PDJ amplicon had a worse outcome with worse disease-free and overall survival. Quantitative RT-PCR confirmed that the PDJ amplicon in TNBC is associated with elevated expression of JAK2 and of the PD-1 ligands. These initial findings demonstrate that the PDJ amplicon is enriched in TNBC, targets signaling pathways that activate the PD-1 mediated immune checkpoint, and identifies patients with a poor prognosis.  相似文献   
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