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961.
Background: Inadequate weight loss after proximal gastric bypass presents a clinical challenge to bariatric surgeons. Pouch size, stoma size and limb length are the variables that can be surgically altered. Aside from conversion to distal bypass, which may have significant negative nutritional sequelae, revisional surgery for this group of patients has not often been reported. The addition of adjustable silicone gastric banding (ASGB) to Roux-en-Y gastric bypass (RYGBP) may be a useful revision strategy because it has potential safety benefits over other revisional approaches. Materials and Methods: We report on 8 patients who presented with inadequate weight loss or significant weight regain after proximal gastric bypass. All patients underwent revision with the placement of an ASGB around the proximal gastric pouch. Bands were adjusted at 6 weeks postoperatively and beyond as needed. Complications and weight loss at the most recent follow-up visit were evaluated. Results: Mean age and body mass index (BMI) at the time of revision were 39 ± 9.9 years and 44.0 ± 4.5 kg/m2 respectively. No patients were lost to follow-up, and they lost an average of 38.1 ± 10.4% and 44.0 ± 36.3% of excess weight and 49.1 ± 20.9% and 52.0 ± 46.0% of excess BMI in 12 and 24 months respectively. Patients lost an average of 62.0 ± 20.5% of excess weight from the combined surgeries in 67 (48–84) months. The only complication was the development of a seroma overlying the area of the port adjustment in one patient. There have been no erosions or band slippages to date. Conclusions: These results indicate that the addition of an ASGB causes significant weight loss in patients with poor weight loss outcome after RYGBP. The fact that no anastomosis or change in absorption is required may make this an attractive revisional strategy. Long- term evaluation in a larger population is warranted.  相似文献   
962.
Background  Bariatric surgery is being conducted more often for morbid obesity, but little evidence exists about how it affects the risk of future cardiovascular events. The goal of this study was to quantify the change in predicted 10-year cardiovascular risk following laparoscopic Roux-en-Y gastric bypass (LRYGBP). Methods  We conducted a prospective clinical study of morbidly obese adults undergoing LRYGBP at a university hospital in the USA. Our primary outcome measure was mean change in 10-year cardiovascular risk at 12 months. We estimated cardiovascular risk by using the Framingham risk equation, which calculates the absolute risk of cardiovascular events for patients with no known history of heart disease, stroke, or peripheral vascular disease by using information on age, sex, blood pressure, total and high-density lipoprotein cholesterol levels, smoking status, and history of diabetes. Results  Ninety-two participants underwent LRYGBP between December 2004 and October 2005. Their predicted baseline 10-year cardiovascular risk was 6.7%. At 6 and 12 months, their predicted risk had decreased to 5.2% and 5.4%, respectively. Assuming no change in risk among untreated patients, this represents an absolute risk reduction of 1.3%; which suggests that 77 morbidly obese patients would have to undergo LRYGBP to avert one new case of cardiovascular disease over the ensuing 10 years (number needed to treat = 77). Conclusion  Our findings indicate that LRYGBP is associated with improvements in cardiovascular risk factors and a corresponding decrease in predicted 10-year risk of cardiovascular disease.  相似文献   
963.
We describe a robotic retroperitoneal approach to renal surgery, optimized in porcine and cadaveric models, and applied to human patients. A retroperitoneal approach for robotic kidney surgery was developed in nonsurvival porcine and a fresh cadaver models, and then utilized in ten patients (three partial nephrectomy, three radical nephrectomy, two simple nephrectomy, one pyeloplasty, one cryoablation). Retroperitoneal access was successfully achieved for robotic renal procedures in six pigs and a human cadaver. Ten human patients (mean age 56 years, range 36–72 years) then underwent a successful retroperitoneal approach for robotic renal surgery. Mean console time was 166 (120–300) min. Mean blood loss was 82 (50–100) ml and average hospital stay was 2.6 (1–5) days. Pathology demonstrated clear cell renal cell carcinoma (four), papillary renal cell carcinoma (two), and xanthogranulomatous pyelonephritis (two). One patient with xanthogranulomatous pyelonephritis required open conversion for failure to progress due to dense adhesions. A retroperitoneal approach is a safe and feasible alternative to a transperitoneal approach for robotic renal surgery, including radical nephrectomy, partial nephrectomy, pyeloplasty, and cryoablation. M. N. Patel and S. A. Kaul contributed equally to this work.  相似文献   
964.
Immunoglobulin (Ig) M nephropathy is defined by electron-dense mesangial deposits and mesangial IgM visible by immunofluorescence (IF) without other histopathologic and immunofluorescent microscopic abnormalities. Certain patients have only immuno-positive (IgM+) IF. Children presenting with steroid-dependent or steroid-resistant nephrotic syndrome have a high prevalence of IgM+ IF with or without electron-dense deposits. We reviewed the clinical course of children with steroid-dependent or steroid-resistant nephrotic syndrome who underwent renal biopsy at Texas Children‘s Hospital from 1989 to 2006 to further characterize IgM+ IF in children with nephrotic syndrome. Of the 55 children with steroid-resistant or -dependent minimal change disease (MCD), 23 had IgM+ IF. Of these 23 children, 61% had microscopic hematuria at presentation, 48% (11/23) were steroid-dependent, and 48% (11/23) steroid-resistant (one underwent biopsy prior to steroid therapy). We compared the efficacy of adjuvant treatment with cyclophosphamide and cyclosporine: 18% initially treated with cyclophosphamide obtained remission, while 55% had no response; 83% obtained subsequent remission with cyclosporine. Of those initially treated with cyclosporine, 88% obtained complete or partial remission. IgM+ IF may be surrogate marker for the severity of MCD. Based on our results, children with MCD and IgM+ IF have a better response to cyclosporine than cyclophosphamide.  相似文献   
965.
Obtaining symmetric and balanced gaps under equilateral loads is a common goal in posterior cruciate ligament (PCL)-retaining and -sacrificing TKAs. Owing to limitations in existing surgical tensors, however, tensing knee ligaments with standardized and symmetric loads has been possible only with the patella subluxated or everted. We therefore determined the influences of (1) patellar eversion versus complete reduction, (2) PCL resection, and (3) load magnitude on gap symmetry and balance in the anterior cruciate ligament (ACL)-deficient knee. We used a novel computer-controlled tensioner to measure gaps in 10 cadavers with an applied force of 50 N, 75 N, and 100 N per side. Gap data were acquired at 0o, 30o, 60o, 90o, and 120o flexion with the patella reduced and everted and with the PCL intact and resected. Everting the patella tightened the medial and lateral flexion gaps between 90o and 120o by 0.7 mm to 2.7 mm. PCL resection increased gaps from 30° to 120° by 1 mm to 3 mm. Increasing the force from 50 N to 100 N increased the mean gap by 0.5 mm. Everting the patella and resecting the PCL influenced gap balance and symmetry. Surgeons should be aware of how these conditions affect gaps during assessment and balancing. Richard Laskin—Deceased. One of the authors (CP) is employed by Praxim Inc, Walpole, MA. Each author certifies that his or her institution has approved the human protocol for this investigation, that all investigations were conducted in conformity with ethical principles of research, and that informed consent for participation in the study was obtained.  相似文献   
966.
X‐linked hypophosphatemia (XLH) is characterized by impaired renal tubular reabsorption of phosphate owing to increased circulating FGF23 levels, resulting in rickets in growing children and impaired bone mineralization. Increased FGF23 decreases renal brush border membrane sodium‐dependent phosphate transporter IIa (Npt2a) causing renal phosphate wasting, impairs 1‐α hydroxylation of 25‐hydroxyvitamin D, and induces the vitamin D 24‐hydroxylase, leading to inappropriately low circulating levels of 1,25‐dihydroxyvitamin D (1,25D). The goal of therapy is prevention of rickets and improvement of growth in children by phosphate and 1,25D supplementation. However, this therapy is often complicated by hypercalcemia and nephrocalcinosis and does not always prevent hyperparathyroidism. To determine if 1,25D or blocking FGF23 action can improve the skeletal phenotype without phosphate supplementation, mice with XLH (Hyp) were treated with daily 1,25D repletion, FGF23 antibodies (FGF23Ab), or biweekly high‐dose 1,25D from d2 to d75 without supplemental phosphate. All treatments maintained normocalcemia, increased serum phosphate, and normalized parathyroid hormone levels. They also prevented the loss of Npt2a, α‐Klotho, and pERK1/2 immunoreactivity observed in the kidneys of untreated Hyp mice. Daily treatment with 1,25D decreased urine phosphate losses despite a marked increase in bone FGF23 mRNA and in circulating FGF23 levels. Daily 1,25D was more effective than other treatments in normalizing the growth plate and metaphyseal organization. In addition to being the only therapy that normalized lumbar vertebral height and body weight, daily 1,25D therapy normalized bone geometry and was more effective than FGF23Ab in improving trabecular bone structure. Daily 1,25D and FGF23Ab improved cortical microarchitecture and whole‐bone biomechanical properties more so than biweekly 1,25D. Thus, monotherapy with 1,25D improves growth, skeletal microarchitecture, and bone strength in the absence of phosphate supplementation despite enhancing FGF23 expression, demonstrating that 1,25D has direct beneficial effects on the skeleton in XLH, independent of its role in phosphate homeostasis. © 2016 American Society for Bone and Mineral Research.  相似文献   
967.
The U.S. Food and Drug Administration (FDA) issued several announcements related to potential risk of bisphosphonates including osteonecrosis of the jaw (2005), atrial fibrillation (2007), and atypical femur fracture (2010). We aimed to evaluate the impact of three FDA drug safety announcements on the use of bisphosphonates in patients with hip fracture using claims data from a U.S. commercial health plan (2004‐2013). We calculated the proportion of patients in each quarter who received a bisphosphonate or other osteoporosis medication in the 6 months following hospitalization for hip fracture. Segmented logistic regression models examined the time trends. Among 22,598 patients with hip fracture, use of bisphosphonate decreased from 15% in 2004 to 3% in the last quarter of 2013. Prior to the 2007 announcement, there was a 4% increase in the odds of bisphosphonate use every quarter (OR 1.04; 95% CI, 1.02 to 1.07). After the 2007 announcement, there was a 4% decrease in the odds of bisphosphonate use (OR 0.96; 95% CI, 0.93 to 0.99) every quarter. The announcement in 2007 was associated with a significant decline in the rate of change of bisphosphonate uses over time (p < 0.001), but no impact on other osteoporosis medication use (p = 0.2). After the 2010 announcement, the odds of bisphosphonate use continued to decrease by 4% (OR 0.96; 95% CI, 0.94 to 0.98) each quarter and the odds of other osteoporosis medication use remained stable over time (OR 0.99; 95% CI, 0.96 to 1.02). The FDA safety announcement related to atrial fibrillation in 2007 was significantly associated with a decrease in bisphosphonate use among patients with hip fracture. © 2016 American Society for Bone and Mineral Research.  相似文献   
968.
Learning processes have been implicated in the development and course of posttraumatic stress disorder (PTSD); however, little is currently known about punishment‐based learning in PTSD. The current study investigated impairments in punishment‐based learning in U.S. veterans. We expected that veterans with PTSD would demonstrate greater punishment‐based learning compared to a non‐PTSD control group. We compared a PTSD group with and without co‐occurring depression (n = 27) to a control group (with and without trauma exposure) without PTSD or depression (n = 29). Participants completed a computerized probabilistic punishment‐based learning task. Compared to the non‐PTSD control group, veterans with PTSD showed significantly greater punishment‐based learning. Specifically, there was a significant Block × Group interaction, F(1, 54) = 4.12, p = .047, η2 = .07. Veterans with PTSD demonstrated greater change in response bias for responding toward a less frequently punished stimulus across blocks. The observed hypersensitivity to punishment in individuals with PTSD may contribute to avoidant responses that are not specific to trauma cues.  相似文献   
969.
The intra‐aortic ventricular assist device (IntraVAD) is a miniature intra‐aortic axial‐flow ventricular assist device (VAD) that works in series with the left ventricle (LV) to assist the compromised heart. Previous in vitro results have shown that the IntraVAD can successfully increase coronary perfusion and offload ventricular volume by operating in reverse‐rotation control (RRc) mode. The RRc mode includes forward rotation in systole and reverse rotation (RR) in diastole. It is necessary to derive a new diffuser design that can be used for the bi‐directional rotation of the IntraVAD. In this work, a dual‐diffuser set (DDS) was proposed to replace the conventional inducer and diffuser upstream and downstream of the pump. The DDS comprised two diffusers, located on both sides of the impeller, omitting the conventional inducer and diffuser. Different configurations of the DDS were designed and manufactured with various combinations of curved and straight blades. All configurations were initially tested in continuous flow, then in a pulsatile mock circulatory loop. A weighted normalized scalar (WNS) was proposed to comprehensively evaluate the hemodynamic effect of the DDS with different configurations. The results show that the maximum of WNS occurred when the upstream diffuser had equal numbers of curved and straight blades and the downstream diffuser had only curved blades. This indicates such a dual‐diffuser design for the IntraVAD can give an optimal cardiac assistance potentially improving ventricular contractility, thereby restoring heart function.  相似文献   
970.
In wound care today, biofilm is a subject area of great interest and debate. There is an increasing awareness that biofilm exists in the majority of non‐healing wounds, and that it is implicated in both recalcitrance and infection. Together with the presence of devitalised host tissue, biofilm is recognised as a component of the wound environment that requires removal to enable wound progression. However, uncertainty exists among wound care practitioners regarding confirmation of the presence of biofilm, and how best to remove biofilm from a non‐healing wound. While recent efforts have been taken to assist practitioners in signs and symptoms of wound biofilm, continuing research is required to characterise and confirm wound biofilm. This research was conducted as part of a market research process to better understand the knowledge levels, experiences, clinical awareness and impact of biofilm in wound care, which was undertaken across the USA and Europe. While knowledge levels and experiences vary from country to country, certain wound characteristics were consistently associated with the presence of biofilm.  相似文献   
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