Limb kinking in supported and unsupported abdominal aortic stent-grafts

PURPOSE: The occurrence of kinking of stent-graft limbs depends on the patient's anatomy and the device used. The purpose of this investigation was to determine the rates of limb kinking in supported and unsupported aortic stent-grafts. MATERIALS AND METHODS: The authors performed a retrospective review of patients undergoing placement of either a Guidant Ancure/EGS or Medtronic Talent aortic stent-graft for the treatment of abdominal aortic aneurysm as part of separate phase II and phase III clinical trials. The records of 91 consecutive patients with 149 limbs were reviewed. The type and configuration of each device and any procedure performed specifically relating to limb patency was recorded. An analysis was then performed comparing the rates of kinking in supported and unsupported groups. A review of the literature was also performed. RESULTS: Overall, there was kinking in 18 of 149 limbs (12%). In the supported stent-graft group, 48 bifurcated and 26 aortomonoiliac grafts were placed, with a total of 122 limbs at risk. Six limbs (5%) in five patients required intervention as a result of limb kinking. Stents were placed intraoperatively in two limbs (2%) and postoperatively in four limbs (3%) for thrombosis or severe stenosis. In the unsupported group, 12 bifurcated and three aortomonoiliac grafts were placed, with a total of 27 limbs at risk. Twelve limbs (44%) in eight patients required some type of intervention as a result of limb kinking. Stents were placed intraoperatively in seven limbs (26%) and postoperatively in five limbs (19%) for thrombosis or severe stenosis. Rates of limb kinking were significantly different between the supported and unsupported groups (P < .0001). CONCLUSIONS: The use of supported versus unsupported stent-grafts impacts the occurrence of limb kinking. A direct comparison of the groups suggests that an unsupported stent-graft will be more than 15 times more likely than a supported system to require intervention because of kinking.     

A Milk-Fat Based Diet Increases Metastasis in the MMTV-PyMT Mouse Model of Breast Cancer

A high-fat diet (HFD) and obesity are risk factors for many diseases including breast cancer. This is particularly important with close to 40% of the current adult population being overweight or obese. Previous studies have implicated that Mediterranean diets (MDs) partially protect against breast cancer. However, to date, the links between diet and breast cancer progression are not well defined. Therefore, to begin to define and assess this, we used an isocaloric control diet (CD) and two HFDs enriched with either olive oil (OOBD, high in oleate, and unsaturated fatty acid in MDs) or a milk fat-based diet (MFBD, high in palmitate and myristate, saturated fatty acids in Western diets) in a mammary polyomavirus middle T antigen mouse model (MMTV-PyMT) of breast cancer. Our data demonstrate that neither MFBD or OOBD altered the growth of primary tumors in the MMTV-PyMT mice. The examination of lung metastases revealed that OOBD mice exhibited fewer surface nodules and smaller metastases when compared to MFBD and CD mice. These data suggest that different fatty acids found in different sources of HFDs may alter breast cancer metastasis.     

Hyperoxia, endothelial progenitor cell mobilization, and diabetic wound healing

Diabetic foot disease is a major health problem, which affects 15% of the 200 million patients with diabetes worldwide. Diminished peripheral blood flow and decreased local neovascularization are critical factors that contribute to the delayed or nonhealing wounds in these patients. The correction of impaired local angiogenesis may be a key component in developing therapeutic protocols for treating chronic wounds of the lower extremity and diabetic foot ulcers. Endothelial progenitor cells (EPCs) are the key cellular effectors of postnatal neovascularization and play a central role in wound healing, but their circulating and wound-level numbers are decreased in diabetes, implicating an abnormality in EPC mobilization and homing mechanisms. The deficiency in EPC mobilization is presumably due to impairment of eNOS-NO cascade in bone marrow (BM). Hyperoxia, induced by a clinically relevant hyperbaric oxygen therapy (HBO) protocol, can significantly enhance the mobilization of EPCs from the BM into peripheral blood. However, increased circulating EPCs failed to reach to wound tissues. This is partly a result of downregulated production of SDF-1alpha in local wound lesions with diabetes. Administration of exogenous SDF-1alpha into wounds reversed the EPC homing impairment and, with hyperoxia, synergistically enhanced EPC mobilization, homing, neovascularization, and wound healing.     

Are adolescents' perceptions of dietary practices associated with their dietary behaviors?

Despite interventions designed to change behavior, many adolescents continue to consume unhealthy foods. Dietary patterns are important for disease prevention, making it necessary to understand the reasons for these poor choices. This cross-sectional study explored the relationship between perception of dietary practices and dietary behaviors among adolescents. Participants (n=15,283; mean age=15 years; 50.7% female) completed the 2004-2005 Texas School Physical Activity and Nutrition survey. Perception of dietary practices included fat content of foods usually eaten and healthiness of usual eating habits. Dietary behavior was measured by self-report of foods eaten the day before survey administration. Composite scores of unhealthy and healthy eating were created. Regression analyses examined whether perception of dietary practices was consistent with actual dietary behavior, controlling for sex, grade, and race/ethnicity, and accounting for the complex sampling design. Higher perceived fat content was associated with increased consumption of unhealthy foods, while higher perceived healthiness of eating was associated with increased consumption of healthy foods. For perceived fat content, the difference in the Healthy Eating Index between extreme categories was 26% (P<0.001), while the difference in the Unhealthy Eating Index between extreme categories was 81% (P<0.001). For perceived healthiness, the difference in the Healthy Eating Index between extreme categories was 23% (P<0.001), while the difference for the Unhealthy Eating Index was 44% (P<0.001). Self-perceptions of dietary practices were significantly associated with dietary behaviors, indicating awareness about the relative nutrient content of foods consumed. Interventions that move beyond dietary knowledge and create changes in the social and physical environment are needed.     

Patient characteristics and service trends following abortion legalization in Mexico City, 2007-10

Legal abortion services have been available in public and private health facilities in Mexico City since April 2007 for pregnancies of up to 12 weeks gestation. As of January 2011, more than 50,000 procedures have been performed by Ministry of Health hospitals and clinics. We researched trends in service users' characteristics, types of procedures performed, post-procedure complications, repeat abortions, and postabortion uptake of contraception in 15 designated hospitals from April 2007 to March 2010. The trend in procedures has been toward more medication and manual vacuum aspiration abortions and fewer done through dilation and curettage. Percentages of post-procedure complications and repeat abortions remain low (2.3 and 0.9 percent, respectively). Uptake of postabortion contraception has increased over time; 85 percent of women selected a method in 2009-10, compared with 73 percent in 2007-08. Our findings indicate that the Ministry of Health's program provides safe services that contribute to the prevention of repeat unintended pregnancies.     

Red blood cell substitutes

Soluble polymerized haemoglobin (polyhaemoglobin) is now in a phase III clinical trials. Patients have received up to 20 units (10 litres) in trauma surgery and other surgery. Polyhaemoglobin can be stored for more than 1 year. Haemoglobin solutions have no blood group antigen and can be used as a 'universal donor' oxygen carrier. They can also be sterilized. With a circulation half-life of 24 hours they are undergoing trials for peri-operative use. For conditions with potential for ischaemia-reperfusion injuries, a new polyhaemoglobin-superoxide dismutase-catalase, which can reduce oxygen radicals, is being developed. Recombinant human haemoglobin has been tested in clinical trials, and a new type of recombinant human haemoglobin that has low affinity for nitric oxide is being developed for clinical trials. To increase the circulation time, artificial red blood cells have been prepared with a bilayer lipid membrane (haemoglobin liposomes) or with a biodegradable polymer membrane-like polylactide (haemoglobin nanocapsules). Synthetic chemicals such as perfluorochemicals are also being developed and tested in clinical trials as red blood cell substitutes.     

Regulated necrosis and failed repair in cisplatin-induced chronic kidney disease

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