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721.
Objective We investigated whether providing participants in an exercise programme with regular feedback on their exercise progress affected their adherence to the programme regimen. Method We conducted a randomized controlled trial. Adult men and women with borderline hypertension and a body mass index ≥ 25.0 were randomized to two intervention groups (groups A and B) and one control group (group C) and were prescribed regular aerobic exercise. During the 12‐week study period, group A was provided with both feedback information on their exercise progress and a health letter, while group B was provided with the health letter only. The main outcome measure was exercise performance, per cent achievement of target exercise level (%) defined as the number of weeks during which the exercise target was reached divided by the number of weeks in the programme. Results were compared using the Kruskal–Wallis test. Results A total of 105 study subjects were randomized into three groups (A, n = 37; B, n = 37 and C, n = 31). Per cent achievement of target exercise level during the 12‐week period was highest in group A (26.5%), followed by groups B (22.9%) and C (17.4%) (P = 0.36). Subjects who received regular feedback during the exercise programme tended to have higher exercise performance. Conclusions In improving adherence to exercise intervention, the provision of regular feedback to participants in an exercise programme may be an effective intervention.  相似文献   
722.

Introduction

Mammographic breast density is a highly heritable (h2 > 0.6) and strong risk factor for breast cancer. We conducted a genome-wide linkage study to identify loci influencing mammographic breast density (MD).

Methods

Epidemiological data were assembled on 1,415 families from the Australia, Northern California and Ontario sites of the Breast Cancer Family Registry, and additional families recruited in Australia and Ontario. Families consisted of sister pairs with age-matched mammograms and data on factors known to influence MD. Single nucleotide polymorphism (SNP) genotyping was performed on 3,952 individuals using the Illumina Infinium 6K linkage panel.

Results

Using a variance components method, genome-wide linkage analysis was performed using quantitative traits obtained by adjusting MD measurements for known covariates. Our primary trait was formed by fitting a linear model to the square root of the percentage of the breast area that was dense (PMD), adjusting for age at mammogram, number of live births, menopausal status, weight, height, weight squared, and menopausal hormone therapy. The maximum logarithm of odds (LOD) score from the genome-wide scan was on chromosome 7p14.1-p13 (LOD = 2.69; 63.5 cM) for covariate-adjusted PMD, with a 1-LOD interval spanning 8.6 cM. A similar signal was seen for the covariate adjusted area of the breast that was dense (DA) phenotype. Simulations showed that the complete sample had adequate power to detect LOD scores of 3 or 3.5 for a locus accounting for 20% of phenotypic variance. A modest peak initially seen on chromosome 7q32.3-q34 increased in strength when only the 513 families with at least two sisters below 50 years of age were included in the analysis (LOD 3.2; 140.7 cM, 1-LOD interval spanning 9.6 cM). In a subgroup analysis, we also found a LOD score of 3.3 for DA phenotype on chromosome 12.11.22-q13.11 (60.8 cM, 1-LOD interval spanning 9.3 cM), overlapping a region identified in a previous study.

Conclusions

The suggestive peaks and the larger linkage signal seen in the subset of pedigrees with younger participants highlight regions of interest for further study to identify genes that determine MD, with the goal of understanding mammographic density and its involvement in susceptibility to breast cancer.  相似文献   
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OBJECTIVE: Icodextrin, a novel glucose polymer solution utilized for peritoneal dialysis, has been demonstrated to have prolonged intraperitoneal (IP) instillation volumes in comparison to standard PBS solutions. In an animal model of ovarian cancer, we explored whether a survival advantage exists utilizing icodextrin rather than PBS as a delivery solution for an infectivity enhanced virotherapy approach. METHODS: Initial experiments evaluated whether icodextrin would adversely affect replication of a clinical grade infectivity enhanced conditionally replicative adenovirus (Delta24-RGD). Virus was added to prepared blinded solutions of PBS or icodextrin (20%) and then evaluated in vitro in various human ovarian cancer cell lines (SKOV3.ip1, PA-1, and Hey) and in vivo in a SKOV3.ip1 human ovarian cancer IP murine model. Viral replication was measured by detecting adenovirus E4 gene levels utilizing QRT-PCR. Survival was subsequently evaluated in a separate SKOV3.ip1 ovarian cancer IP murine model. Cohorts of mice were treated in blinded fashion with PBS alone, icodextrin alone, PBS+Delta24-RGD, or icodextrin+Delta24-RGD. Survival data were plotted on Kaplan-Meier curve and statistical calculations performed using the log-rank test. RESULTS: There was no adverse affect of icodextrin on vector replication in the ovarian cancer cell lines nor murine model tumor samples evaluated. Median survival in the IP treated animal cohorts was 23 days for the PBS group, 40 days for the icodextrin group, 65 days for the PBS+Delta24-RGD group, and 105 days for icodextrin+Delta24-RGD (p=0.023). Of note, 5 of the 10 mice in the icodextrin+Delta24-RGD group were alive at the end of the study period, all without evidence of tumor (120 days). CONCLUSIONS: These experiments suggest that the use of dialysates such as icodextrin may further enhance the therapeutic effects of novel IP virotherapy and other gene therapy strategies for ovarian cancer. Phase I studies utilizing icodextrin-based virotherapy for ovarian cancer are currently in development.  相似文献   
726.

Introduction

Since the invention of the pulse oximeter, physicians often or even routinely perform venous blood gas analysis (VBGA). However, it has not been generally agreed that the application of VBGA is practically meaningful in routine clinical situations such as in an ED.

Methods

We measured venous-arterial Pco2 difference ((v-a)Pco2) and arterial-venous pH difference ((a-v)pH), and analyzed the physiological factors that affect these differences in healthy volunteers and hyperventilation patients.

Results

In healthy volunteers, both (v-a)Pco2 and (a-v)pH increased during finger exercise or hyperventilation in an intensity-dependent manner. Doppler echography indicated that increases in (v-a)Pco2 and (a-v)pH during hyperventilation are induced by reduction of peripheral blood flow. Approximately 40% of patients with untreated respiratory alkalosis were found to be incorrectly diagnosed if based only on VBGA.

Conclusions

It must be noted that VBGA may lead to overestimation of acidosis and to underestimation of respiratory alkalosis when extremities muscles are active or patients are hyperventilating. Physicians should keep these limitations in mind when conducting VBGA.  相似文献   
727.
Background: Aortic stiffness assessed by brachio-ankle pulse wave velocity (baPWV) can be used to predict cardiovascular events. However, baPWV is dependent on blood pressure. Antihypertensive drugs have been reported to reduce baPWV; but it is difficult to determine if this effect is associated with lowered blood pressure or reduced arterial stiffness.Objectives: The primary end point of this study was to assess whether antihypertensive drugs reduce arterial stiffness as estimated by cardio-ankle vascular index (CAVI). The secondary end point was to compare the effects of 2 widely used drugs, the calcium-channel blocker amlodipine and the angiotensin II receptor blocker candesartan, on arterial stiffness.Methods: Between October 2005 and September 2006, consecutive Japanese outpatients with essential hypertension (EHT) (defined as using antihypertensive drugs at screening, systolic blood pressure [SBP] > 140 mm Hg, or diastolic BP [DBP] >90 mm Hg) were assigned to treatment for 24 weeks with either amlodipine (5-10 mg/d) or candesartan (8-12 mg/d). Arterial stiffness was evaluated with CAVI before and after 24 weeks of treatment. Relative change in arterial stiffness from baseline was also compared. The evaluator was blinded to treatment.Results: Twenty patients (11 men, 9 women; mean [SD] age, 62 [10] years) were included in the study. There were no significant differences in clinical characteristics between the 2 groups. At baseline, mean (SD) CAVI was not significantly different in the amlodipine group compared with the candesartan group (8.93 [0.93] vs 8.46 [1.34], respectively). During the 24-week treatment period, mean SBP and DBP decreased significantly in both the amlodipine (14/10 mm Hg; P = 0.006 and P = 0.005) and the candesartan groups (13/11 mm Hg; P = 0.033 and P = 0.005). Amlodipine was associated with a significant change in CAVI from baseline (8.93 [0.93] vs 8.60 [1.50]; P = 0.017), whereas candesartan was not (8.46 [1.34] vs 8.81 [1.20]). The percentage change in CAVI was significantly different in the amlodipine group compared with the candesartan group (−7.14 [8.83] vs 5.85 [16.0], respectively; P = 0.038). After 24 weeks of treatment, the CAVI of the amlodipine group was still numerically larger than baseline CAVI of the candesartan group, although the difference was not statistically significant. Furthermore, there was no significant difference in absolute CAVI between the 2 groups after 24 weeks, but the relative change from baseline was significant in favor of amlodipine. Logistic regression analysis revealed that amlodipine improved CAVI independent of its antihypertensive effect.Conclusion: These data suggest that amlodipine and candesartan had different effects on aortic stiffness estimated by CAVI, despite similar effects on brachial blood pressure after 24 weeks of treatment in these Japanese patients with EHT.  相似文献   
728.
Purpose Alternative and complementary therapeutic strategies need to be developed for metastatic breast cancer. Virotherapy is a novel therapeutic approach for the treatment of cancer in which the replicating virus itself is the anticancer agent. However, the success of virotherapy has been limited due to inefficient virus delivery to the tumor site. The present study addresses the utility of human mesenchymal stem cells (hMSCs) as intermediate carriers for conditionally replicating adenoviruses (CRAds) to target metastatic breast cancer in vivo. Experimental design HMSC were transduced with CRAds. We used a SCID mouse xenograft model to examine the effects of systemically injected CRAd loaded hMSC or CRAd alone on the growth of MDA-MB-231 derived pulmonary metastases (experimental metastases model) in vivo and on overall survival. Results Intravenous injection of CRAd loaded hMSCs into mice with established MDA-MB-231 pulmonary metastatic disease homed to the tumor site and led to extended mouse survival compared to mice treated with CRAd alone. Conclusion Injected hMSCs transduced with CRAds suppressed the growth of pulmonary metastases, presumably through viral amplification in the hMSCs. Thus, hMSCs may be an effective platform for the targeted delivery of CRAds to distant cancer sites such as metastatic breast cancer.  相似文献   
729.
Blue naevus is an acquired benign melanocytic naevus. It is a firm, sharply defined dark blue to grey-black papule or nodule, which is likely to arise from the arrested dermal melanocytes in the dermis. In the last few years, blue naevus has attracted much attention due to the recognition of new entities and to its confusion with malignant melanoma. We report a 69-year-old man who developed a blue-black nodular lesion with satellitosis on his scalp. Although clinically it was thought to be a malignant melanoma, histopathological investigation and conservative methods such as dermatoscopy and power Doppler ultrasonography did not confirm this diagnosis. Histopathological examination excluded malignant melanoma, as there were no cellular atypia and mitotic activity in either the nodular lesion or the satellitosis. Doppler ultrasonography confirmed the benign nature of the lesion. Dermatoscopic examination showed homogeneous steel-blue pigmentation with individual blue globules, dots and some brown veils, and confirmed the histopathological diagnosis. To the best of our knowledge, our case is the third reported case of a blue naevus with satellitosis mimicking malignant melanoma.  相似文献   
730.
Crown fractures and luxations occur most frequently of all dental injuries. An appropriate treatment plan after an injury is important for a good prognosis. Guidelines are useful for delivering the best care possible in an efficient manner. The International Association of Dental Traumatology (IADT) has developed a consensus statement after a review of the dental literature and group discussions. Experienced researchers and clinicians from various specialties were included in the group. In cases where the data did not appear conclusive, recommendations were based on the consensus opinion of the IADT board members. The guidelines represent the current best evidence, based on literature research and professional opinion. In this first article of three, the IADT Guidelines for management of fractures and luxations of permanent teeth will be presented.  相似文献   
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