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Mei L. Tan Peng Shao Anna M. Friedhuber Mallory van Moorst Mina Elahy Sivanjah Indumathy Dave E. Dunstan Yongzhong Wei Crispin R. Dass 《Biomaterials》2014
Bone defects caused by fractures or cancer-mediated destruction are debilitating. Chitosan is commonly used in scaffold matrices for bone healing, but rarely as a free drug. We demonstrate that free chitosan promotes osteoblast proliferation and osteogenesis in mesenchymal stem cells, increases osteopontin and collagen I expression, and reduces osteoclastogenesis. Chitosan inhibits invasion of endothelial cells, downregulating uPA/R, MT1-MMP, cdc42 and Rac1. Better healing of bone fractures with greater trabecular bone formation was observed in mice treated with chitosan. Chitosan induces apoptosis in osteotropic prostate and breast cancer cells via caspase-2 and -3 activation, and reduces their establishment in bone. Chitosan is pro-apoptotic in osteosarcoma cells, but not their normal counterpart, osteoblasts, or chondrosarcoma cells. Systemic delivery of chitosan does not perturb angiogenesis, bone volume or instinctive behaviour in pregnant mice, but decreases foetal length and changes pancreatic secretory acini. With certain controls in place, chitosan could be useful for bone trauma management. 相似文献
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Jing Qi Yuman Fong Leonard Saltz Michael I. D'Angelica Nancy E. Kemeny Mithat Gonen Jinru Shia Amita Shukla‐Dave William M. Jarnagin Richard K. G. Do Lawrence H. Schwartz Jason A. Koutcher Kristen L. Zakian 《NMR in biomedicine》2013,26(2):204-212
Hepatic steatosis is a hallmark of chemotherapy‐induced liver injury. We made serial 1H MRS measurements of hepatic lipids in patients over the time course of a 24‐week chemotherapeutic regimen to determine whether 1H MRS could be used to monitor the progression of chemotherapy‐induced steatosis. Thirty‐four patients with stage III or IV colorectal cancer receiving 5‐fluorouracil, folinic acid and oxaliplatin (n = 21) or hepatic arterial infusion of floxuridine with systemic irinotecan (n = 13) were studied prospectively. 1H MRS studies were performed at baseline and after 6 and 24 weeks of treatment. A 1H MR spectrum was acquired from the liver during a breath hold and the ratio of fat to fat + water (FFW) was calculated to give a measure of hepatic triglycerides (HTGCs). The methodology was histologically validated in 18 patients and the reproducibility was assessed in 16 normal volunteers. Twenty‐seven patients completed baseline, 6‐week and 24‐week 1H MRS examinations and one was censored. Thirteen of 26 patients (50%) showed an increase in FFW after completion of treatment. Six patients (23%) developed hepatic steatosis and two patients converted from steatosis to nonsteatotic liver. Patients whose 6‐week hepatic lipid levels had increased significantly relative to baseline also had a high probability of lipid elevation relative to baseline at the completion of treatment. Serial 1H MRS is effective for the monitoring of HTGC changes during chemotherapy and for the detection of chemotherapy‐associated steatosis. Six of 26 patients developed steatosis during chemotherapy. Lipid changes were observable at 6 weeks. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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Louise Cowpertwait Dave Clarke 《International journal of mental health and addiction》2013,11(2):247-268
Web-based psychological interventions aim to make psychological treatments more accessible and minimize clinician input, but their effectiveness requires further examination. The purposes of the present study are to evaluate the outcomes of web-based interventions for treating depressed adults using meta-analytic techniques, and to examine moderating effects on these interventions. A random-effects analysis yielded a medium effect of web-based interventions compared to controls, with a significant reduction in depression and improvement in well-being. Regression analysis revealed moderating effects of human support and inclusion of reminders in treatments for depression. Also, mean attrition rates were similar to face-to-face treatment, moderated by inclusion of human support. Future research on client suitability and clinical significance are needed. Trials on web-based interventions are encouraged to address quality constraints apparent in existing studies, namely the need for explicit acknowledgment of multiple publications, ensuring quality of control groups, and careful reporting of methods and results. It was concluded that web-based interventions are effective ways of treating depression and enhancing well-being, particularly if supplemented with personal engagement. 相似文献
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Chronic obstructive pulmonary disease (COPD) is associated with high morbidity and mortality. COPD is typified by persistent, progressive airflow limitation and a range of respiratory and systemic symptoms such as breathlessness, coughing, wheezing, depression, anxiety, general fatigue, and sleeping difficulties. Despite receiving treatment for COPD, many patients suffer from regular symptoms that affect their daily lives and lead to increased morbidity. These symptoms vary in severity, frequency, and type, and can occur at any time throughout the 24-h day, with over half of patients with COPD experiencing symptoms in the morning, during the day, and at nighttime. Despite the prevalence of symptoms, patient and physician perception of the impact of COPD symptoms on patients’ lives is not always in concordance. Dual bronchodilator therapy with a long-acting muscarinic antagonist (LAMA) and long-acting beta agonist (LABA) has the potential to treat the symptoms of COPD in addition to improving lung function. This review therefore examines the burden of symptoms experienced throughout the day by patients with COPD and the evidence for combined LAMA/LABA treatment in terms of symptom management. As patients with COPD experience varying symptoms throughout the course of their disease, the role of tailoring treatment to the individual needs of the patient is also examined. We conclude that the symptoms of COPD are troublesome, variable, can occur during all parts of the 24-h day, and have a substantial impact on patients’ health status and quality of life. In order to provide effective, patient-orientated care, patients with COPD should be evaluated on the basis of lung function, the frequency of symptoms, and patient-perceived impact of symptoms on their lives. Therapy should be chosen carefully based on individualized assessment, ensuring personalization to the individual needs of the patient. 相似文献
66.
Varinder K. Randhawa Brian E. Grunau Derek B. Debicki Jian Zhou Ahmed F. Hegazy Terry McPherson A. Dave Nagpal 《The Canadian journal of cardiology》2018,34(2):156-167
Survival with a good quality of life after cardiac arrest continues to be abysmal. Coordinated resuscitative care does not end with the effective return of spontaneous circulation (ROSC)—in fact, quite the contrary is true. Along with identifying and appropriately treating the precipitating cause, various components of the post–cardiac arrest syndrome also require diligent observation and management, including post–cardiac arrest neurologic injury and myocardial dysfunction, systemic ischemia-reperfusion phenomenon with potential consequent multiorgan failure, and the various sequelae of critical illness. There is growing evidence that an early invasive approach to coronary reperfusion with percutaneous coronary intervention, together with active targeted temperature management and optimization of hemodynamic, ventilator, and metabolic parameters, may improve survival and neurologic outcomes in cardiac arrest survivors. Neuroprognostication is complex, as are survivorship issues and long-term rehabilitation. Our paramedics, emergency physicians, and resuscitation specialists are all to be congratulated for ever-increasing success with ROSC… but now the real work begins. 相似文献
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Jessica Ayers Jamie Cook Rachel A. Koenig Evan M. Sisson Dave L. Dixon 《Current atherosclerosis reports》2018,20(6):29