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BackgroundCumulative dose-dependent nonischemic cardiomyopathy (NICM) remains a significant risk with the use of some chemotherapeutic agents. In this context, omega-3 polyunsaturated fatty acids (PUFA) have been investigated for their cardioprotective potential in rodent and in vitro models of anthracycline toxicity, with conflicting results. This study evaluated prophylactic omega-3 PUFA supplementation in a large-animal model of anthracycline-induced NICM.Methods and ResultsMerino sheep were randomized to oral drenching with omega-3 PUFA (fish oil; n = 8) or olive oil placebo (n = 9) 3 weeks before commencing repeated intracoronary infusions of doxorubicin (DOX) to induce cardiac dysfunction. Cumulative DOX dose was 3.6 mg/kg. Drenching was continued for 12 weeks after final DOX exposure. Despite significant increases in tissue omega-3 PUFA levels (P < .05 vs placebo), omega-3–treated sheep displayed greater signs of anthracycline cardiotoxicity than placebo animals, consisting of left ventricular dilatation and a greater decline in ejection fraction (P < .05), although myocardial fibrosis burden was similar in both groups.ConclusionsDietary intake of omega-3 PUFA fails to prevent and may indeed exacerbate DOX-induced cardiotoxicity. Clinical use of omega-3 supplementation during chemotherapy should be deferred until more information is available regarding the mechanisms of interaction between fatty acids and the myocardium during anthracycline exposure.  相似文献   
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Cardiovascular magnetic resonance (CMR) imaging is widely established, free of radioactive material or ionizing radiation, and the accepted noninvasive gold standard for numerous noninvasive cardiac markers. Using a technique called T2-weighted imaging, CMR can be used to assess myocardial edema as a reliable marker for acute, potentially reversible myocardial injury. Contrast agents are not required as the myocardial free water content affects the magnetic properties of the tissue, thus providing inherent image contrast. In this review, we illustrate the utility of T2-weighted techniques in the assessment of myocardial edema in a range of clinical scenarios. The detection of myocardial edema is clinically relevant in many acute settings and may be further helpful to better understand the pathophysiology of many non-acute clinical diseases. Currently, T2-weighted CMR represents the only imaging modality that can accurately depict and quantify the presence of myocardial edema in a noninvasive fashion. Thus, T2-weighted imaging should be included in a comprehensive CMR imaging protocol, especially if an acute injury is suspected.  相似文献   
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PurposeTo assess the toxicity and cosmetic results in breast cancer patients undergoing adjuvant partial breast irradiation (PBI) to a total dose of 40 Gy in 10 daily fractions (4 Gy/fraction).Methods and materialsPatients affected by early-stage breast cancer were enrolled in this phase II trial. Patients had to be 60 years old and treated with breast conservative surgery for early stage (pT1–T2 pN0–N1a) invasive ductal carcinoma.Results77 patients were enrolled. Median follow-up was 18 months. The proposed schedule was well tolerated. One patient reported Grade 3 pain at the site of irradiation. Four (5%) patients experience Grade 2 erythema. Late Grade 2 and 1 fibrosis was observed in 3 (4%) and 14 (18%) patients, respectively. Cosmesis was judged “good/excellent” and “poor” in 75 (97%) and in 2 (3%) patients, respectively.Conclusions40 Gy in 10 daily fractions, 4 Gy/fraction, is a well tolerated regimen to deliver PBI.  相似文献   
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Introduction: Colloidal drug delivery systems (CDDSs) are innovative carriers that have been studied in pharmaceutical field from many years to overcome unfavorable physical and chemical features of synthetic drugs. Recently the use of CDDS as carriers for phytochemicals has seen an exponential increase which, in some cases, has led to the rediscovery of ancient and forgotten natural molecules.

Area covered: This article focuses on the main features of CDDS, particularly micro- and nanoemulsions, vesicular carriers and micro- and nanoparticles, loaded with natural active compounds. A detailed review of the literature is presented, introducing the importance of these systems in terms of their capability to optimize the stability of phytochemicals, their absorption through biological membranes and their bioavailability.

Expert opinion: The delivery of phytochemicals is problematic due to poor solubility, poor permeability, low bioavailability, instability in biological milieu and extensive first-pass metabolism. Global research efforts investigating nanotechnology have attempted to overcome these limitations rediscovering and, in some cases, ‘discovering ex novo’ unexpected virtues and benefits associated to these compounds. The ‘nanotechnological approach’ can definitely enhance the pharmacokinetics and therapeutic index of natural active compounds and improve their performance in therapy.  相似文献   

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Purpose

To report the extended long-term results of the use of tension-free vaginal tape(TVT) and trans-obturator tape (TOT) for the treatment of female stress urinary incontinence (SUI).

Methods

A prospective, multicentre randomized clinical trial comparing the use of TVT and TOT was used to evaluate 87 patients. The inclusion criteria were stress or mixed UI associated with urethral hyper mobility (the stress component was clinically predominant), while the exclusion criteria were previous anti-incontinence surgery and/or pelvic organ prolapse. The objective cure criteria were a negative provocative stress test and a negative 1-h pad test, with no further treatment for SUI. The subjective cure criteria were a 3-day voiding diary, quality-of-life questionnaires (UDI6–IIQ7), and patient satisfaction on a scale from 0 to 10.

Results

Eighty-seven patients were evaluated (47 TOT and 40 TVT) at a median follow-up of 100 months. Subjective and objective cure rates were 59.6 and 70.2 % in the TOT group and 75 and 87.5 % in the TVT group. The mid-to-long-term trend was a decreasing continence rate in patients who underwent TOT, compared with a stable rate for TVT. The Kaplan–Meier survival curve showed that continence rate decreased for up to 25 months after surgery, with stabilization thereafter for the TVT group while continuing to drop in the TOT group, with no inter-group difference.

Conclusion

The patients in both groups were highly satisfied at long-term follow-up. The overall continence rate worsened for both groups within 25 months. While the results tend to stabilize in the TVT group, a further decline in the TOT was observed.
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