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81.
No-touch aorta off-pump coronary surgery: the effect on stroke 总被引:7,自引:0,他引:7
Lev-Ran O Braunstein R Sharony R Kramer A Paz Y Mohr R Uretzky G 《The Journal of thoracic and cardiovascular surgery》2005,129(2):307-313
OBJECTIVE: Studies examining the neuroprotective effects of off-pump coronary artery bypass grafting have shown inconsistent results. Most studies, however, have not differentiated between clampless and clamp off-pump techniques. The aim of this study was to evaluate the effect of avoiding aortic manipulation on major neurologic outcomes after off-pump coronary artery bypass grafting. METHODS: A total of 700 consecutive patients undergoing multiple-vessel off-pump coronary artery bypass grafting between 2000 and 2003 were included. The 429 patients undergoing aortic no-touch technique were compared with 271 patients in whom partial aortic clamps were applied. The aorta was screened by manual palpation, and epiaortic ultrasonography was used selectively. RESULTS: The frequency of detected atherosclerotic aortic disease was higher in the no-touch group (17.4% vs 5.1%, P < .0001). No-touch revascularization was achieved with arterial conduits, arranged in T-graft or in situ configurations (50%). The respective graft/patient ratios were 2.5 +/- 0.6 and 2.6 +/- 0.6 in the side-clamp and no-touch groups ( P = .009); however, revascularization of the posterolateral myocardial territory was comparable (87% vs 90%, difference not significant). The incidence of stroke (0.2% vs 2.2%, P = .01) was significantly lower in the no-touch group (1/429). Logistic regression identified partial aortic clamping as the only independent predictor of stroke (odds ratio 28.5, confidence interval 0.22-333, P = .009), increasing this risk 28-fold. Peripheral vascular disease ( P = .068), diabetes ( P = .072), and history of stroke ( P = .074) trended toward stroke. CONCLUSIONS: Avoiding partial aortic clamping during off-pump coronary artery bypass grafting provides superior neurologic outcome. The results are reproducible and irrespective of the severity of aortic disease or the method of aortic screening. This technique is recommended whenever technically feasible. 相似文献
82.
Ilan Shimon Varda Eshed Ram Doolman Ben-Ami Sela Avraham Karasik Iris Vered 《Osteoporosis international》2005,16(12):1591-1596
Male hypogonadism is associated with low bone mineral density (BMD) and an increased risk of fractures. Testosterone replacement therapy improves BMD in young hypogonadal men. This effect is milder in older patients, who are at greater risk for fractures. We studied the effects of alendronate or placebo on BMD in 22 osteoporotic men, 29–69 years of age (mean, 50.2±11.2 years) with long-standing hypogonadism, receiving standard testosterone replacement treatment. Alendronate 10 mg daily ( n =11) increased lumbar-spine BMD by 6.0 and 8.4% at 6 and 12 months, respectively, compared with –0.5% at 6 months and +3.3% at 12 months in the placebo group ( n =11; P <0.005). Alendronate also increased mean femoral-neck BMD by 1.9% after 1 year, compared to a 1.4% decrease with placebo ( P <0.005), and increased the total body bone mineral content by 4.4%, compared to a 0.6% decrease with placebo ( P =0.07). After 6 months alendronate suppressed urinary deoxypyridinoline by 50% ( P <0.005), compared to a 24% decrease in the placebo group. Both the alendronate and placebo groups continued with alendronate 70 mg once weekly for the following 2 years. Lumbar-spine BMD during this open-label study phase did not change significantly in the group originally treated with alendronate, but continued to increase in the placebo-alendronate group by 5.4, 6.5, and 6.2% after 18 (6 months of alendronate), 24 and 36 months, respectively ( P <0.05). Femoral-neck BMD continued to increase in both groups receiving active therapy; in the alendronate-alendronate group by 3.7, 2.7, and 5.2% after 18, 24, and 36 months, respectively ( P =0.01), and in the placebo-alendronate group by 0.7 and 1.9% at 24 (first 12 months of alendronate) and 36 months, respectively ( P <0.05). Our results support the long-term administration of alendronate along with testosterone replacement to men with hypogonadism-induced osteoporosis. 相似文献
83.
The purpose of this study was to investigate the effect of general anesthesia and surgery on melatonin production, and to
assess the relationship between melatonin secretion and cortisol levels. Twenty (9 males and 11 females) consecutive otherwise
healthy patients aged 27 to 52 years were included in this study. The patients underwent laparoscopic cholecystectomy or laparoscopic
hernioplasty. All patients had general anesthesia with the same anesthetic drugs. Serum cortisol levels were measured at several
time periods. Urine collections for melatonin were performed from 18:00 to 7:00 the day prior to surgery, on the operation
day, and on the first postoperative day. Baseline melatonin metabolites were measured the night prior to surgery, and the
level was found to be 1979 ± 1.76 ng. The value decreased to 1802 ± 1.82 ng (NS) on the night of surgery, and it became a
significantly higher, reaching 2981 ± 1.55 ng the night after surgery (p = .003). The baseline daytime cortisol level was significantly lower than the baseline night cortisol level (6.87 ± 1.51
μg/dl, 14.89 ± 1.66 micrograms/dl, respectively, p < 0.0001). Surgery induced a significant increase in both day and night cortisol levels. Daytime cortisol levels increased
from 6.89 ± 1.51μg/dl to 16.90 ± 1.27μg/dl (p < 0.0001), whereas right levels increased from 14.89 ± 1.66 μg/dl to 29.20 ± 1.24 μg/dl (p <0.0001). The morning after surgery, cortisol levels decreased to 10.16 ± 1.40 μg/dl, lower than the value obtained on the
day of surgery (p < 0.0001). As was true of melatonin, cortisol levels did not reach the pre operative level (p < 0.005). The finding of the current study is that melatonin and cortisol levels show an inverse correlation after surgery. 相似文献
84.
BACKGROUND: Proteinuria is a significant problem in medicine today, although glomerular events underlying it are unknown. Products of cytochrome P450 (CYP450) pathway of arachidonic acid metabolism are increasingly recognized as playing major roles in renal function. We used in vitro albumin permeability (P(alb)) as a measure of injury and puromycin aminonucleoside (PAN) as an injurious agent to test the hypothesis that 20-hydroxyeicosatetraenoic acid (20-HETE) protects the glomerular filtration barrier from increased P(alb). METHODS: We determined P(alb) in the following experimental groups: (1) isolated rat glomeruli incubated with PAN (5 microg/mL) for 5, 15, 30 or 60 minutes; (2) isolated glomeruli preincubated with 20-HETE (1.0 nmol/L to 100 nmol/L) for 15 minutes followed by additional incubation with PAN (5 microg/mL) for 15 minutes; (3) isolated glomeruli from rats treated with the CYP450 4A inducer clofibrate, and incubated with PAN (5 microg/mL) for 15 minutes; and (4) appropriate controls for each group. CYP450 4A levels were measured in glomeruli isolated from rats treated with clofibrate or vehicle. RESULTS: PAN increased P(alb) of isolated glomeruli as early as 5 minutes (P(alb) 0.33 +/- 0.21, P < 0.05 vs. control). Maximal effect occurred at 30 minutes (P(alb) 0.75 +/- 0.16, P < 0.001 vs. control). Inclusion of 20-HETE (100 nmol/L) blocked the increased P(alb) caused by PAN (P(alb) 0.05 +/- 0.13). Likewise, glomeruli isolated from rats treated with clofibrate were protected from PAN-induced increase in P(alb) (P(alb) 0.19 +/- 0.03). Treatment with clofibrate significantly increased glomerular CYP450 4A expression. CONCLUSION: PAN directly and immediately affects the glomerular permeability barrier. Furthermore, exogenous 20-HETE or clofibrate treatment protects glomeruli from increased P(alb) caused by PAN. Relative lack of 20-HETE may be a general characteristic of proteinuric states. Conversely, measures used to treat and/or prevent proteinuria may act to restore or increase glomerular 20-HETE levels. 相似文献
85.
Platelet function profiles in patients with type 2 diabetes and coronary artery disease on combined aspirin and clopidogrel treatment 总被引:8,自引:0,他引:8
Angiolillo DJ Fernandez-Ortiz A Bernardo E Ramírez C Sabaté M Jimenez-Quevedo P Hernández R Moreno R Escaned J Alfonso F Bañuelos C Costa MA Bass TA Macaya C 《Diabetes》2005,54(8):2430-2435
To assess platelet function profiles in diabetic and nondiabetic patients on aspirin and clopidogrel therapy, two patient populations were included to investigate the 1) acute effects of a 300-mg clopidogrel loading dose (group 1, n = 52) and 2) long-term effects of clopidogrel (group 2, n = 120) on platelet function in diabetic compared with nondiabetic patients already on aspirin treatment. Patients were stratified according to the presence of type 2 diabetes. Platelet aggregation was assessed using light transmittance aggregometry (groups 1 and 2). Platelet activation (P-selectin expression and PAC-1 binding) was determined using whole-blood flow cytometry (group 2). Clopidogrel response was also assessed. In group 1, platelet aggregation was significantly increased in diabetic (n = 16) compared with nondiabetic (n = 36) patients at baseline and up to 24 h following a 300-mg loading dose (P = 0.005). In group 2, platelet aggregation and activation were increased in diabetic (n = 60) compared with nondiabetic (n = 60) subjects (P < 0.05 for all platelet function assays). Diabetic subjects had a higher number of clopidogrel nonresponders (P = 0.04). Diabetic patients have increased platelet reactivity compared with nondiabetic subjects on combined aspirin and clopidogrel treatment. Reduced sensitivity to antiplatelet drugs may contribute to the increased atherothombotic risk in diabetic patients. 相似文献
86.
Effect of Balloon‐Expandable Transcatheter Aortic Valve Replacement Positioning: A Patient‐Specific Numerical Model 下载免费PDF全文
Matteo Bianchi Gil Marom Ram P. Ghosh Harold A. Fernandez James R. Taylor Jr. Marvin J. Slepian Danny Bluestein 《Artificial organs》2016,40(12):E292-E304
Transcatheter aortic valve replacement (TAVR) has emerged as a life‐saving and effective alternative to surgical valve replacement in high‐risk, elderly patients with severe calcific aortic stenosis. Despite its early promise, certain limitations and adverse events, such as suboptimal placement and valve migration, have been reported. In the present study, it was aimed to evaluate the effect of various TAVR deployment locations on the procedural outcome by assessing the risk for valve migration. The deployment of a balloon‐expandable Edwards SAPIEN valve was simulated via finite element analysis in a patient‐specific calcified aortic root, which was reconstructed from CT scans of a retrospective case of valve migration. The deployment location was parametrized in three configurations and the anchorage was quantitatively assessed based on the contact between the stent and the native valve during the deployment and recoil phases. The proximal deployment led to lower contact area between the native leaflets and the stent which poses higher risk for valve migration. The distal and midway positions resulted in comparable outcomes, with the former providing a slightly better anchorage. The approach presented might be used as a predictive tool for procedural planning in order to prevent prosthesis migration and achieve better clinical outcomes. 相似文献
87.
Effect of 4‐chloro‐7‐trifluoromethyl‐10H‐benzo[4,5]furo[3,2‐b]indole‐1‐carboxylic acid on the intraurethral pressure in a rat model of benign prostatic hyperplasia 下载免费PDF全文
88.
Evzen Machytka Ram Chuttani Martina Bojkova Tomas Kupka Marek Buzga Kathryn Stecco Samuel Levy Shantanu Gaur 《Obesity surgery》2016,26(3):512-516
Background
Endoscopic gastric balloons have been used effectively as weight loss devices for decades, but the requirement for endoscopy and sedation poses several limitations. The goal of this pilot study was to evaluate the safety and performance of a prototype version of Elipse?, a procedureless gastric balloon.Methods
Eight patients (mean BMI?=?31.0 kg/m2) participated in this study. Each patient swallowed one Elipse? balloon intended to remain in the stomach for 6 weeks, self-empty, and then pass. Each balloon was filled with 450 mL of filling fluid. Patients returned every 2 weeks for abdominal ultrasound. No specific diet or exercise plan was prescribed.Results
All eight patients successfully swallowed the device. The most common adverse events were nausea and vomiting. There were no serious adverse events, and all balloons were excreted safely. Despite not being prescribed a diet or exercise plan, all eight patients lost weight. In 6/8 patients, the balloon remained full through 6 weeks, self-emptied, and passed. In one patient, the balloon appeared partially collapsed on ultrasound after 11 days and was endoscopically punctured. One asymptomatic patient elected to have the balloon endoscopically punctured after 19 days. Both balloons passed in the stool after 4 days. In both cases, endoscopic examination of the upper GI tract showed no abnormalities.Conclusions
This pilot study demonstrates the safety and performance of Elipse?, a procedureless gastric balloon for weight loss. Future studies will test a commercial design filled to 550 mL intended to last in the stomach for at least 12 weeks.89.
90.
Mandeep Kumar Garg Ram Prakash Galwa Deepak Goyal N. Khandelwal 《Journal of gastrointestinal surgery》2009,13(4):821-823
Introduction Gallstone ileus is a life-threatening surgical emergency where characteristic imaging can be diagnostic. Jejunum is the one
of the rare sites of gallstone impaction.
Materials and Methods We hereby emphasize the role of multidetector computed tomography (MDCT) by describing a case of jejunal gallstone ileus with
cholecystoduodenal fistula in a 59-year-old lady who presented with symptoms and signs of proximal small bowel obstruction.
Conclusion MDCT of the abdomen established the diagnosis, and the patient managed surgically. 相似文献