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81.
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This study reports on a large series of 200 dual kidney transplantations (DKTs) from expanded criteria donors (ECDs) and proposes specific ways to optimize outcomes. Data concerning 200 DKTs performed in the last 14 yr were retrospectively analyzed. Kidneys from high‐risk ECD were allocated for use in DKTs on an old‐for‐old basis after histological assessment. Different surgical techniques and immunosuppressant regimens were used over time, and the outcomes are discussed. Donors and recipients were a median 73 (70–77) and a 62 (58–67) yr old, respectively. Delayed graft function occurred in 31.5% of cases, and acute rejection in 13.5%. Patient and graft survival at five yr were 90.4% and 85.8%, respectively. Unilateral kidney placement was preferred for 75% of patients, and was associated with a low rate of surgical complications. Our current standard therapy comprising low‐dose calcineurin inhibitors (CNIs) associated with mammalian target of rapamycin inhibitors (mTOR) and steroids appears to offer the best risk/benefit profile for elderly patients undergoing DKT. In our experience, outcomes after DKT can be improved by: (i) kidney clinical–histological assessment; (ii) unilateral kidney placement; (iii) minimal use of CNI associated with mTOR.  相似文献   
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The brown macroalgae Bifurcaria bifurcata have gained special attention due to their ability to biosynthesize linear diterpenes (rarely found in other species). However, the conventional extraction methods normally used to extract these compounds involve organic solvents and often high temperatures, leading to the degradation of thermo-labile compounds. In this context, the main objective of this work was to study and optimize for the first time the extraction of diterpenes from B. bifurcata through an environmentally friendly methodology, namely, high pressure extraction (HPE) using ethanol : water. This was compared with conventional Soxhlet extraction, using dichloromethane. Box–Behnken design was employed to evaluate the linear, quadratic, and interaction effects of 3 independent variables (pressure (X1), ethanol percentage (X2), and time of extraction (X3)) on response variables (extraction yield and diterpenes content (mg g−1 of extract and mg kg−1 of dry weight)) and the optimal extraction conditions (X1: 600 MPa; X2: 80%; X3: 5 min) were estimated by response surface methodology (RSM). B. bifurcata extract obtained under HPE optimal conditions showed a diterpenes content (612.2 mg g−1 of extract) 12.2 fold higher than that obtained by conventional extraction (50.1 mg g−1 of extract). The HPE extract, obtained under optimal conditions, showed antioxidant and antibacterial (against Staphylococcus aureus) activities considerably higher than the Soxhlet extract, and also presented a promising synergic effect with antibiotics, improving the antibiotic efficacy against S. aureus. In conclusion, these results indicate that HPE is a promising methodology, compared to conventional methodologies to obtain linear diterpene rich extracts from B. bifurcata with great potential to be exploited in pharmaceutical or biomedical applications.

Bioactive linear diterpenes were selectively extracted from the macroalga Bifurcaria bifurcata through optimized high-pressure extraction.  相似文献   
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AMP-18,一种新发现的胃黏膜保护因子   总被引:3,自引:0,他引:3  
AMP-18是一种新发现的由胃腺体上皮细胞合成的小分子蛋白质,独特表达于胃黏膜,机体其他部位少见,胃癌组织中表达缺失.AMP-18 由185个氨基酸组成,除去N端信号肽(20个氨基酸)后大小约18 ku,第54-150个氨基酸组成高度保守的结构域(BRICHOS区域)承担主要的生理功能.AMP-18由胃腺体上皮细胞以胞吐的方式分泌到胃黏液中,他的合成和分泌与个体生长发育有关,并受福斯高林、吲哚美辛、地塞米松等药物的影响.目前发现 AMP-18的生理功能主要有促进胃黏膜上皮细胞的有丝分裂,促进细胞的迁徙,促胃肠黏膜损伤的修复,保持胃肠黏膜的完整等.  相似文献   
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IntroductionWith the emergence of the COVID-19 pandemic, all elective surgery was temporarily suspended in the UK, allowing for diversion of resource to manage the anticipated surge of critically unwell patients. Continuing to deliver time-critical surgical care is important to avoid excess morbidity and mortality from pathologies unrelated to COVID-19. We describe the implementation and short-term surgical outcomes from a system to deliver time-critical elective surgical care to patients during the COVID-19 pandemic.Materials and methodsA protocol for the prioritisation and safe delivery of time-critical surgery at a COVID-19 ‘clean’ site was implemented at the Nuffield Health Exeter Hospital, an independent sector hospital in the southwest of England. Outcomes to 30 days postoperatively were recorded, including unplanned admissions after daycase surgery, readmissions and complications, as well as the incidence of perioperative COVID-19 infection in patients and staff.ResultsA total of 128 surgical procedures were performed during a 31-day period by a range of specialties including breast, plastics, urology, gynaecology, vascular and cardiology. There was one unplanned admission and and two readmissions. Six complications were identified, and all were Clavien-Dindo grade 1 or 2. All 128 patients had preoperative COVID-19 swabs, one of which was positive and the patient had their surgery delayed. Ten patients were tested for COVID-19 postoperatively, with none testing positive.ConclusionThis study has demonstrated the implementation of a safe system for delivery of time-critical elective surgical care at a COVID-19 clean site. Other healthcare providers may benefit from implementation of similar methodology as hospitals plan to restart elective surgery.  相似文献   
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目的:通过使用CT三维测量髋臼发育情况及髋臼对股骨头覆盖率对比性观察,整体反映髋臼发育情况。方法:①观察对象:选择2003-06/2005-04对41例发育性髋关节脱位患者55个髋关节。其中男12例,女29例;年龄18个月~6岁。患髋右侧23例,左侧32例,其中双侧12例。健康侧27髋。患儿家属均知情同意。②实验方法:所有患儿使用PQ6000型多层螺旋CT扫描,扫描数据进行骨组织三维重建。将测量数据制成图表,显示三维的髋臼发育情况,并量化表示髋臼的缺损情况。③实验评估:计算不同截面正常侧髋臼指数、中心边缘角(假设符合正态分布)的均数、标准差、分布范围及95%可信区间。观察发育性髋关节脱位术前术后骨骼形态学变化。分别在术前、术后测量患者患侧髋臼指数、中心边缘角和前倾角,测量值均分别与正常值进行对比。结果:患侧55个髋,健康侧27髋,均进入结果分析。①发育性髋关节脱位术前术后骨骼形态学变化:术前55侧发育性髋关节脱位髋关节脱位程度为,参照T"nnis分类方法,Ⅰ度5髋(9.1%),Ⅱ度11髋(20%),Ⅲ度32髋(58.2%),Ⅳ度7髋(12.7%)。术后患者均表现髋臼α角均>90°,头臼呈同心圆对位,Shenton线连续,股骨头较术前明显发育,原先未出现头骺的患者,出现头骺,但较正常仍偏小;髋臼口呈类圆形,髋臼边缘欠光滑,髋臼整体呈一定程度前倾。②术前术后髋臼指数、中心边缘角和前倾角变化对比:术后患者的髋臼指数和前倾角与正常对照组之间差异无显著性(P>0.05),术后患者的中心边缘角大于正常对照组[(33.4±2.6)°(29.1±2.0)°,P<0.01],术后患者的髋臼指数和前倾角测量值均小于术前(P<0.01)。结论:介绍了一种对髋臼形态测量的新方法,它能够全面反映髋臼的发育情况,不但增加了对中心边缘髋臼病理改变的认识程度,还为手术提供了精确的可信度较高的矫形设计方案。  相似文献   
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Objective

To assess the concordance of MRI T2 mapping sequence with CT-arthrography for traumatic and degenerative chondral lesions.

Subjects and methods

Fifteen consecutive patients were included prospectively from September 2011 to April 2012. They referred for CT-arthrography examination for degenerative or traumatic knee pain and had also knee 3 T MRI with T2 mapping sequences. CT-arthrography was used as benchmark diagnostic test for chondral lesion, read in a consensual way by two senior musculo-skeletal radiologists. The same, blinded to CT-arthrography results, independently reviewed standard and T2 Mapping MRI sequences and rated number of hyaline cartilage lesions, and their grade according to the International Cartilage Research Society Score (ICRS) in each anatomical compartment. Size and T2 value of the largest lesion was measured. We used Mac Nemar test to assess concordance between MRI and CT-arthrography findings, a regression model to compare CT-arthrography ICRS classification to T2 values, and Wilcoxon test for inter-reader agreement.

Results

Because of artifact and loss to follow-up, 11 patients were finally included. Concordance of T2 mapping MRI with CT-arthrography for reader 1 and reader 2 were respectively 90% and 80% in medial compartment, 50% and 70% in lateral compartment, 90% and 70% in anterior compartment. There was no significant correlation between CT-arthrography ICRS classification and T2 values (P > 0.06). No significant differences between reader 1 and reader 2 were observed when evaluating the prevalence of knee lesions (P = 0.25 for the medial compartment, P = 0.62 for the lateral compartment and P = 1 for the anterior zone).

Conclusion

T2 mapping is a reproducible imaging technique, with a good concordance to CT-arthrography for detection and size of chondral lesions, with no correlation between CT-arthrography ICRS grade and T2 values.  相似文献   
90.

Pedicle screw fixation enables enhanced three-dimensional correction of spinal deformities and effectively shortens the distal fusion level. However, the choice of distal fusion level is still controversial in single thoracic idiopathic scoliosis with the lumbar compensatory curve not crossing the middle line (Lenke type 1 with modifier A or King type III and IV curves).The authors retrospectively analyzed 31 patients treated by segmental pedicular instrumentation alone, affected by a single thoracic adolescent idiopathic scoliosis with a compensatory lumbar curve not crossing the midline (Lenke 1A), with an average age of 16.3 years (range 10–22 years). The patients with regard to the King classification were also assessed. A statistical analysis was performed to determine whether the two groups (King III, King IV) presented differences concerning the level of the stable vertebra (SV), end vertebra (EV), and neutral vertebra (NV) and were also analyzed the results at follow-up regarding the relationships between the SV, EV, and lowest instrumented vertebra (LIV). The statistical analysis showed a significant difference between the two curve types. In the King III type curve the SV, EV, and NV appeared to be more proximal than those of the King IV type curve and the segments between the SV, EV, and NV appeared to be reduced in King III curves compared with King IV curves. At a follow-up of 3.2 years (range 2.2–5) the thoracic curve showed a correction of 58.4% (from 62.3° to 26.6°) and compensatory lumbar curve an average spontaneous correction of 52.4% (from 38.1° to 18.1°).The position of the LIV was shorter than the position of the SV in 30 patients (97%) with an average “salvage” of 2.1 (from 1 to 4) distal fusion levels. Four cases (13%), all affected by a King IV type curve, presented at follow-up an unsatisfactory results due to an “adding on” phenomenon. The statistical analysis confirmed that this phenomenon was correlated with The King IV curve (P = 0.043; Chi-square test) and that the only predictive parameter for its onset was the LIV–SV difference (odds ratio = 0.093; with a confidence interval of 0.008–1): every time that in King IV curve type the LIV was three or more levels shorter than the stable vertebra at follow-up the “adding on” phenomenon was present. The authors conclude that Lenke’s type 1 with modifier A includes two kinds of curves, King III and King IV and that the Lenke’s type 2 curves and King V with the lumbar curve not crossing the middle line have a similar behavior. Therefore, it is of authors’ opinion that “the adding on phenomenon” could be prevented by more rigidly defining K. IV versus K. III curves. In Lenke’s 1/2 A-K. IV/V type with the rotation of the first vertebra just below the thoracic lower EV in the same direction as the thoracic curve, and when SV and EV show more than two levels of difference, it is necessary to extend the lower fusion down to L2 or L3 (not more than two levels shorter than the SV). Whereas in Lenke’s 1/2 A-K. III/V with the rotation of the first proximal vertebra of lumbar curve in the opposite direction to the thoracic apex and when SV and EV show not more than two level gap differences, the position of the lowest instrumented vertebra can be two or three levels shorter than the stable vertebra with satisfactory postoperative spinal balance. Therefore, the stable vertebra and the rotation of lumbar curve are considered to be a reliable guide for selecting the lower level of fusion.

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