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41.
BackgroundAdjustable gastric banding has been widely used in Europe, but recently gastric bypass (Roux-en-Y gastric bypass [RYGB]) has become the procedure of choice. With a gastric banding failure rate of nearly 40% at 5 years, the need for revisional surgery is increasing. The effect of a failed previous bariatric surgery on the weight loss curve after RYGB is still a controversial issue.MethodsA total of 259 patients underwent RYGB from 2003 to 2007, 58 after failed gastric banding and 201 as primary surgery. All the procedures were laparoscopically performed by the same surgeon at a single institution. The postoperative course and the percentage of excess weight loss were compared between the 2 groups.ResultsThe 2 groups were similar in age and initial body mass index (46.3 ± 7.2 kg/m2 for revision versus 47.7 ± 6.7 kg/m2 for primary RYGB). In contrast, the prerevision body mass index was 43.2 ± 7.0 kg/m2. Revisional RYGB required a significantly longer operative time (128.3 ± 25.9 minutes versus 89.0 ± 14.7 minutes, P <.0001) and the morbidity was greater (8.6% versus 5.5%), but no patient died in the postoperative period after revision. As determined from the initial body mass index, the 1-year percentage of excess weight loss was comparable between the 2 groups (66.1% ± 26.8% and 70.4% ± 18.9%).ConclusionWhen RYGB is performed after an adjustable gastric band failure to restore weight loss or because of a complication, the weight loss curve is similar to that after primary RYGB. Therefore, the strategy of adjustable gastric banding first is an option that does not seem to preclude satisfactory weight loss after revision to RYGB.  相似文献   
42.
Background  Patients undergoing bariatric surgery with a gastric bypass lose about 66% of excess weight. Although this procedure induces weight loss, it is unknown whether it leads to protein malnutrition, which is studied here. Methods  One hundred ten obese patients (body mass index, 47.9 ± 8.6 kg/m2) undergoing gastric bypass had a measurement of plasma albumin and transthyretin (formerly prealbumin) and a calculation of nutritional risk index (NRI) before and throughout the 2 years following the surgery. Results  All but five patients lost more than 15% of initial weight; the mean loss of excess weight was 65.2 ± 26.4% at 2 years. Plasma concentrations of albumin and transthyretin decreased after surgery, but while albumin returned to initial values after 12 months, transthyretin remained low. Only one patient had an albumin below 30 g/l; another one had a transthyretin lower than 110 mg/l. All NRI scores were lower than 83.5 (62 ± 5, ranging 44–70), qualifying patients for severe malnutrition. Conclusion  Malnutrition is difficult to diagnose in obese patients undergoing surgery. The large weight loss is most often not associated with protein malnutrition. Whether gastric bypass induces protein malnutrition remains to be established.  相似文献   
43.
IntroductionDeveloping positron emission tomography (PET) radiotracers for non-invasive study of the cholinergic system is crucial to the understanding of neurodegenerative diseases. Although several acetylcholinesterase (AChE) PET tracers radiolabeled with carbon-11 exist, no fluorinated radiotracer is currently used in clinical imaging studies. The purpose of the present study is to describe the first fluorinated PET radiotracer for this brain enzyme.MethodsThree structural analogs of huprine, a specific AChE inhibitor presenting high affinity towards AChE in vitro, were synthesized and labeled with fluorine-18 via a mesylate/fluoro-nucleophilic aliphatic substitution: ([18 F]-FHUa, [18 F]-FHUb and [18 F]-FHUc). Initial biological evaluation included in vitro autoradiography in rat with competition with an AChE inhibitor at different concentrations, and microPET-scan on anesthetized rats. In vivo PET studies in anesthetized cat focused on [18 F]-FHUa.Results and ConclusionsAlthough radiosynthesis of these huprine analogs was straightforward, they showed poor brain penetration potential, partially reversed after pharmacological inhibition of P-glycoprotein. These results indicated that current huprine analogs are not suitable for PET mapping of brain AChE receptors, but require physicochemical modulation in order to increase brain penetration.  相似文献   
44.

Purpose

Femoral neck fracture is a major public health problem in elderly persons, representing the main source of osteoporosis-related mortality and morbidity. In this study, we aimed at comparing radiographic texture analysis with three-dimensional (3D) microarchitecture in human femurs, and at evaluating whether bone texture analysis improved the assessment of the femoral neck fracture risk other than that obtainable by bone mineral density (BMD).

Materials and methods

Thirteen osteoporotic femoral heads from patients who fractured their femoral neck and twelve non-fractured femoral heads from osteoarthritic patients were studied using respectively (1) a new high-resolution digital X-ray device (BMA™, D3A Medical Systems) allowing for bone texture analysis with fractal parameter Hmean, and (2) a micro-computed tomograph (CT) for 3D microarchitecture. BMD was measured postoperatively by DXA in all patients in the contralateral femur.

Results

In these femoral heads, we found that fractal parameter Hmean was correlated with 3D microarchitecture parameters: bone volume fraction (BV/TV), trabecular number (Tb.N), trabecular separation (Tb.Sp) and fractal dimension (FD) respectively (p < 0.05). Then, fractal parameter Hmean was significantly lower in the femoral heads from the fractured group than from the non-fractured group (p < 0.01). Finally, multiple regression analysis showed that combining bone texture analysis and total hip BMD significantly improved the estimation of the femoral neck fracture risk from adjusted r2 = 0.46 to adjusted r2 = 0.67 (p < 0.05).

Conclusion

Radiographic bone texture analysis was correlated with 3D microarchitecture parameters in the femoral head, provided accurate discrimination between the femoral heads from the fractured and non-fractured groups, and significantly improved the estimation of the femoral neck fracture risk when combined with BMD.  相似文献   
45.

Purpose

To prospectively evaluate magnetic resonance (MR) enterography for detecting mesenteric small-bowel tumours (MSBTs) and assess the added value of gadolinium-chelate injection.

Material and methods

Over a 2-year period MR enterography examinations of 75 patients (33 men, 42 women; mean age, 53.8 years; range, 19–85) with suspected MSBT were blindly analysed by two readers for the presence of MSBT. Sensitivities, specificities, predictive positive values (PPVs), negative predictive values (NPVs) and accuracies of MR enterography for the detection of MSBT were calculated on per-patient and per-lesion bases. The McNemar test was used to compare sensitivities and specificities of the unenhanced and gadolinium-enhanced sets of MR enterographies.

Results

Thirty-seven MSBTs were pathologically confirmed in 26 patients. The mean tolerance score of the examinations was 0.7. On a per-patient basis, sensitivity, specificity, PPV, NPV and accuracy for detection of MSBT were 96 % [95 % CI, 89–100 %], 96 % [90–100 %], 93 % [83–100 %], 98 % [94–100 %] and 96 % [92–100 %], respectively. On a per-lesion basis, sensitivity and PPV were 70 % [56–85 %] and 93 % [83–100 %], respectively. Gadolinium injection yielded higher sensitivities on both bases (P?=?0.008).

Conclusion

MR enterography is an accurate and well-tolerated imaging modality for detecting MSBT. Intravenous administration of gadolinium-chelate improves sensitivity for MSBT detection.

Key Points

? MR enterography accurately detects mesenteric small bowel tumours. ? MR enterography is a well-tolerated imaging technique. ? Intravenous administration of gadolinium chelate improves sensitivity for detecting small-bowel tumours.  相似文献   
46.
BACKGROUND: Of patients who have undergone gastric banding, 11-25% will require a major reoperation with band removal and conversion to another bariatric procedure after they have failed to lose sufficient weight or have developed dysphagia or reflux. The aim of this study was to evaluate the respective benefits of Roux-en-Y gastric band (RYGB) or biliopancreatic diversion with duodenal switch (BPD-DS) after failed gastric banding and whether 1 of the 2 procedures might be a better procedure for such cases. METHODS: RYGB or BPD-DS was performed according to the institutional protocols with synchronous band removal, irrespective of the reason for failure. RESULTS: Of the 53 patients, 32 underwent laparoscopic RYGB for a body mass index (BMI) of 43.1 +/- 6.4 kg/m(2) (BMI 45.8 +/- 6.4 kg/m(2) before laparoscopic adjustable gastric banding) and 21 underwent BPD-DS for a BMI of 46.0 +/- 5.5 kg/m(2) (BMI 49.6 +/- 5.2 kg/m(2) before laparoscopic adjustable gastric banding). BPD-DS required significantly longer operative times (239.7 +/- 55.8 versus 135 +/- 26.7 minutes) and resulted in more complications (62% versus 12.5%; P <.002). No patients died postoperatively. The 2 groups of patients had a similar BMI at 12 and 18 months after revision (BMI 33.4 +/- 5.6 kg/m(2) and 31.4 +/- 3.5 kg/m(2)). The weight loss was greater after BPD-DS than after RYGB compared with the prerevision weight loss (66.2% versus 58.8% excess weight loss) or initial weight (73% versus 61.8%), although this was not significant. CONCLUSION: Despite an excessive rate of complications that were, in part, related to the learning curve in this series, BPD-DS resulted in greater weight loss compared with RYGB. However, both procedures were successful after failed gastric banding. A more accurate definition of failure could help to determine the respective indications for revisional surgery.  相似文献   
47.
BackgroundEndoscopy plays a pivotal role in the management of adverse events (AE) following bariatric surgery. Leaks, fistulae, and post-operative collection after sleeve gastrectomy (SG) may occur in up to 10% of cases.ObjectivesTo evaluate the efficacy and safety of endoscopic internal drainage (EID) for the management of leak, fistula, and collection following SG.SettingRetrospective, observational, single center study on patients referred from several bariatric surgery departments to an endoscopic referral center.MethodsEID was used as first-line treatment for the management of leaks, fistulae, and collections. Leaks and fistulae were treated with double pigtail stent (DPS) deployment in order to guarantee internal drainage and second intention cavity obliteration. Collections were treated with endoscropic ultrasound (EUS)–guided deployment of DPS or lumen apposing metal stents.ResultsA total of 617 patients (83.3% female; mean age, 43.1 yr) were enrolled in the study for leak (n = 300, 48.6%), fistula (n = 285, 46.2%), and collection (n = 32, 5.2%). Median follow-up was 19.5 months. Overall clinical success was 84.7% whereas 15.3% of cases required revisional surgery after EID failure. Clinical success according to type of AE was 89.5%, 78.5%, and 90% for leak, fistula, and collection, respectively. A total of 10 of 547 (1.8%) presented a recurrence during follow-up. A total of 28 (4.5%) AE related to the endoscopic treatment occurred. At univariate logistic regression predictors of failure were: fistula (OR 2.012), combined endoscopic approach (OR 2.319), need for emergency surgery (OR 1.755), and previous endoscopic treatment (OR 4.818).ConclusionEarly EID for the management of leak, fistula, and post-operative collection after SG seems a safe and effective first-line approach with good long-term results.  相似文献   
48.
IntroductionFibroepithelial polyps (FEP) of the lower urinary tract are relatively common in adults but rare in children, with fewer than 250 cases reported in the literature to date.ObjectiveThe aim of this study was to address the experience of FEP management in children.Study designA retrospective multicenter review was undertaken in children with defined FEP of the lower urinary tract managed between 2008 and 2018. The data at 18 pediatric surgery centers were collected. Their demographic, radiological, surgical, and pathological information were reviewed.ResultsA total of 33 children (26 boys; 7 girls) were treated for FEP of the lower urinary tract at 13 centers. The most common presentation was urinary outflow as hematuria (41%), acute urinary retention (25%), dysuria (19%), or urinary infections (28%). A prenatal diagnosis was made for three patients with hydronephrosis. Almost all of the children (94%) underwent ultrasound imaging of the urinary tract as the first diagnostic examination, 23 (70%) of them also either had an MRI (15%), cystourethrography (25%), computerized tomography (6%), or cystoscopy (45%). Two of these children (6%) had a biopsy prior to the surgery. The median preoperative delay was 7.52 (range: 1–48) months. Most of the patients were treated endoscopically, although four (12.1%) had open surgery and two (6.1%) had an additional incision for specimen extraction. The median hospital stay was 1.5 (range: 1–10) days. There were no recurrences and no complications after a median follow-up of 13 (range: 1–34) months.DiscussionThe main limitation of our study is the retrospective design, although it is the largest one for this pathology.ConclusionThis series supports sonography as the most suitable diagnosis tool before endoscopy to confirm the diagnosis and to perform the resection for most FEP in children. This report confirms the recognized benign nature in the absence of recurrences.Level of EvidenceLevel V.  相似文献   
49.
50.
Available data on clinical presentation and mortality of coronavirus disease-2019 (COVID-19) in heart transplant (HT) recipients remain limited. We report a case series of laboratory-confirmed COVID-19 in 39 HT recipients from 3 French heart transplant centres (mean age 54.4 ± 14.8 years; 66.7% males). Hospital admission was required for 35 (89.7%) cases including 14/39 (35.9%) cases being admitted in intensive care unit. Immunosuppressive medications were reduced or discontinued in 74.4% of the patients. After a median follow-up of 54 (19–80) days, death and death or need for mechanical ventilation occurred in 25.6% and 33.3% of patients, respectively. Elevated C-reactive protein and lung involvement ≥50% on chest computed tomography (CT) at admission were associated with an increased risk of death or need for mechanical ventilation. Mortality rate from March to June in the entire 3-centre HT recipient cohort was 56% higher in 2020 compared to the time-matched 2019 cohort (2% vs. 1.28%, P = 0.15). In a meta-analysis including 4 studies, pre-existing diabetes mellitus (OR 3.60, 95% CI 1.43–9.06, I2 = 0%, P = 0.006) and chronic kidney disease stage III or higher (OR 3.79, 95% CI 1.39–10.31, I2 = 0%, P = 0.009) were associated with increased mortality. These findings highlight the aggressive clinical course of COVID-19 in HT recipients.  相似文献   
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