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1.
These guidelines have been produced with the involvement of the Association of Breast Surgery and the British Association of Plastic, Reconstructive and Aesthetic Surgeons. Recommendations have been derived after a review of published data regarding the use of acellular dermal matrix (ADM), biological and synthetic mesh in breast reconstruction. The guidelines represent a consensus opinion on the optimal management of patients having biological or synthetic mesh assisted breast reconstruction informed by peer-review publications. The Guidelines should be used to inform clinical decision making. Ultimately, members of the MDT remain responsible for the treatment of patients under their care.  相似文献   
2.
《The surgeon》2020,18(4):202-207
IntroductionThe objective of this study is to evaluate outcomes and complications in patients with single-stage ADM-implant based immediate breast reconstruction with and without radiotherapy (RT), highlighting the effects of RT on the reconstruction.Materials and methodsThis prospective study recruited 91 consecutive patients who underwent skin-sparing, nipple-sparing or wise-pattern skin reduction mastectomy with direct-to-implant breast reconstruction with ADMs using sub-pectoral or pre-pectoral approach at the two breast units. Early and late complications like seroma, delayed wound healing, wound breakdown, infection, capsular contracture, implant loss and revision surgery were evaluated in the RT and non-RT groups.ResultsIn the total cohort of 91 patients, 29 received adjuvant RT and 62 did not need RT. In the RT group, 3–7% of them had early complications like seroma, wound infections and delayed healing. 20.7% had post-RT capsular contractures which either required revision surgery with autologous flap (6.9%) or capsulotomy with exchange of implant (6.9%). In the non-RT group, 7–9% cases had seroma & wound infections, 3.06% had delayed wound healing and 7.25% had capsular contracture. 13.04% required revision surgery due to infection, implant loss or failure to achieve expectations. The total loss of implants in the cohort was 7.14% (RT group 6.9% and non-RT group 7.25%). The need for PMRT could have been predicted pre-operatively in the RT group in 55.17% cases based on the extent of disease, multifocality, tumour grade and positive LN status on imaging.ConclusionADM based reconstruction in patients anticipated to receive adjuvant RT is always debatable. Though there is no significant difference in the revision surgeries in our study of the 2 groups, the rate of capsular contracture as expected, was higher in the RT group. Hence, pre-operative discussion on the need for RT highlighting the risks and complications will help patients make a better-informed choice.  相似文献   
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The exocrine pancreas exhibits a distinctive capacity for tissue regeneration and renewal following injury. This regenerative ability has important implications for a variety of disorders, including pancreatitis and pancreatic cancer, diseases associated with high morbidity and mortality. Thus, understanding its underlying mechanisms may help in developing therapeutic interventions. Serotonin has been recognized as a potent mitogen for a variety of cells and tissues. Here we investigated whether serotonin exerts a mitogenic effect in pancreatic acinar cells in three regenerative models, inflammatory tissue injury following pancreatitis, tissue loss following partial pancreatectomy, and thyroid hormone‐stimulated acinar proliferation. Genetic and pharmacological techniques were used to modulate serotonin levels in vivo. Acinar dedifferentiation and cell cycle progression during the regenerative phase were investigated over the course of 2 weeks. By comparing acinar proliferation in the different murine models of regeneration, we found that serotonin did not affect the clonal regeneration of mature acinar cells. Serotonin was, however, required for acinar dedifferentiation following inflammation‐mediated tissue injury. Specifically, lack of serotonin resulted in delayed up‐regulation of progenitor genes and delayed the formation of acinar‐to‐ductal metaplasia and defective acinar cell proliferation. We identified serotonin‐dependent acinar secretion as a key step in progenitor‐based regeneration, as it promoted acinar cell dedifferentiation and the recruitment of type 2 macrophages. Finally, we identified a regulatory Hes1–Ptfa axis in the uninjured adult pancreas, activated by zymogen secretion. Our findings indicated that serotonin plays a critical role in the regeneration of the adult pancreas following pancreatitis by promoting the dedifferentiation of acinar cells. Copyright © 2015 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.  相似文献   
4.
Trans‐differentiation of pancreatic acinar cells into ductal‐like lesions, a process defined as acinar‐to‐ductal metaplasia (ADM), is observed in the course of organ regeneration following pancreatitis. In addition, ADM is found in association with pre‐malignant PanIN lesions and correlates with an increased risk of pancreatic adenocarcinoma (PDAC). Human PDAC samples show down‐regulation of p21WAF1/Cip1, a key regulator of cell cycle and cell differentiation. Here we investigated whether p21 down‐regulation is implicated in controlling the early events of acinar cell trans‐differentiation and ADM formation. p21‐mediated regulation of ADM formation and regression was analysed in vivo during the course of cerulein‐induced pancreatitis, using wild‐type (WT) and p21‐deficient (p21?/?) mice. Biochemical and immunohistochemical methods were used to evaluate disease progression over 2 weeks of the disease and during a recovery phase. We found that p21 was strongly up‐regulated in WT acinar cells during pancreatitis, while it was absent in ADM areas, suggesting that p21 down‐regulation is associated with ADM formation. In support of this hypothesis, p21?/? mice showed a significant increase in number and size of metaplasia. In addition, p21 over‐expression in acinar cells reduced ADM formation in vitro, suggesting that the protein regulates the metaplastic transition in a cell‐autonomous manner. p21?/? mice displayed increased expression and relocalization of β‐catenin both during pancreatitis and in the subsequent recovery phase. Finally, loss of p21 was accompanied by increased DNA damage and development of senescence. Our findings are consistent with a gate‐keeper role of p21 in acinar cells to limit senescence activation and ADM formation during pancreatic regeneration. Copyright © 2014 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd  相似文献   
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6.
目的研究负载抗原的树突状细胞(DC)联合细胞因子诱导的杀伤细胞(CIK)对肝癌细胞株HepG2/ADM多药耐药性的逆转作用。方法 HepG2/ADM细胞冻融抗原冲击DC,联合CIK细胞与HepG2/ADM细胞共培养,以未负载抗原的DCCIK作为阴性对照,以未经共培养处理的HepG2/ADM细胞作为空白对照。采用流式细胞仪在细胞处理后不同时间点检测HepG2/ADM细胞内罗丹明-123(R-123)浓度和阿霉素(ADM)浓度,采用Western blot检测细胞内P-糖蛋白(P-gp)水平。结果与DC-CIK共培养相比,负载抗原的DC-CIK共培养能够明显抑制HepG2/ADM细胞内R-123的外排,提高细胞内ADM浓度,同时降低细胞内P-gp水平(P0.05)。结论经抗原冲击的DC和CIK共培养可明显抑制HepG2/ADM细胞内R-123的外排,提高细胞内ADM浓度,抑制P-gp表达,从而有效逆转肝癌细胞多药耐药性。  相似文献   
7.
目的 观察西达本胺(CDM)能否影响人慢性髓系白血病耐药株K562/ADM细胞对柔红霉素(DNR)的敏感性,并探讨其可能的分子机制。方法 体外常规培养K562细胞和K562/ADM细胞,给予不同剂量CDM和(或)DNR处理48 h后,采用细胞计数试剂盒8(CCK-8)法检测CDM与DNR对K562和K562/ADM细胞的毒性作用,采用Chou-Talalay中效分析法对两药的联合效应进行评价,采用流式细胞术检测细胞增殖、细胞周期和凋亡,采用Western blotting方法检测组蛋白2AX(H2AX)、γH2AX(Ser139)、共济失调毛细血管扩张征突变基因(ATM)、p-ATM(Ser1981)、乳腺癌易感蛋白l(BRCA1)和p-BRCA1(Ser1524)的蛋白表达水平。 结果 DNR可剂量依赖性地抑制K562/ADM细胞活力(P<0.05),半数抑制浓度(IC50)为11.76 μmol/L,耐药倍数为18.09;CDM可协同增强DNR对K562/ADM细胞的抑制作用置信区间(CI)(CI<1),反转倍数为8.11;与对照组相比,DNR组细胞增殖率显著降低(P<0.05),G2/M期细胞比例和凋亡率明显升高(P<0.05),而无毒剂量的CDM可协同增强DNR引起的细胞增殖抑制、G2/M期阻滞和细胞凋亡(P<0.05);耐药株K562/ADM细胞中ATM和BRCA1蛋白表达水平显著高于其亲代K562细胞(P<0.05);DNR可上调K562/ADM细胞中H2AX、ATM和BRCA1蛋白的磷酸化水平(P<0.05);CDM与DNR联用可使γH2AX蛋白水平进一步升高,但p-ATM和p BRCA1蛋白水平的变化则相反(P<0.05)。 结论 CMD可反转K562/ADM细胞对DNR的耐药性,这可能与上调H2AX蛋白的磷酸化水平以及下调ATM和BRCA1蛋白的磷酸化水平有关。  相似文献   
8.
目的介绍生物束带(脱细胞异体真皮,HADM)"阶梯式倒U形"阴道紧缩术的临床效果和操作方法。方法:从本手术项目组2018年1月至2019年9月期间实施的"阶梯式倒U形"生物束带阴道紧缩术案例中,随机选择50例作为研究对象;均由同一手术项目组按照统一操作规范,采用生物束带实施"阶梯式倒U形"阴道紧缩术。统计平均手术时间;观察术前、术后(即刻)阴道口及阴道前1/3大小,计算阴道收紧有效率;测量术前、术后(即刻)会阴体高度,计算会阴体抬高有效率;检测术后2月阴道握持力,计算阴道握持力增加有效率;观察术后并发症及其发生率;随访术后2月、6月、1年患者对手术满意度。结果:50例"阶梯式倒U形"生物束带阴道紧缩术平均手术时间28min;48例术后阴道明显收紧,有效率达96%;38例会阴体高度明显抬高,有效率达76%;45例术后2月阴道握持力明显增加,有效率达90%;术后均未发生排异反应,无直肠损伤、血肿、感染等。30例得到有效随访,随访率达60%;术后2月、6月、1年患者满意度分别为88%、97%、98%。结论:"阶梯式倒U形"生物束带阴道紧缩术手术操作快捷,可有效收紧阴道、修复会阴体和增加阴道握持力等,具有临床效果确切、并发症少、安全性高、可操作性强和求美者满意度高等优势,值得临床推广应用。  相似文献   
9.
In recent years, it has become increasingly popular to use matrices, such as acellular dermal matrices, in implant-based breast reconstruction. To lower the cost and to avoid implanting biological material, the use of synthetic meshes has been proposed. This is the first study examining TIGR® Mesh in a larger series of immediate breast reconstruction. The aims of the study were to examine complications and predictors for complications. All consecutive patients operated on with breast reconstruction with TIGR® Matrix Surgical Mesh and tissue expanders (TEs) or permanent implant between March 2015 and September 2016 in our department were prospectively included. Exclusion criteria were ongoing smoking, BMI (kg/m2)?>?30, planned postoperative radiation, and inability to leave informed consent. Fifteen breasts (23%) were affected by complications within 30 d: four (6.2%) major complications and eleven (17%) minor complications. The major complications included two implant losses and one pulmonary embolism (PE). Predictors for a complication were age over 51 years, BMI over 24.5?kg/m2, large resection weight, and the need for a wise pattern excision of skin. Four minor surgical complications occurred after 30 d (minimum follow-up 17 months). There were no implant losses. In addition, minor aesthetic corrections, such as dog-ear resection, were performed in 10 breasts. In conclusion, breast reconstruction with a TE in combination with TIGR® Matrix Surgical Mesh can be performed with a low complication rate.  相似文献   
10.
目的:以耐多柔比星(adriamycin,ADM)的人急性髓系白血病(acute myeloid leukemia,AML)耐药细胞株HL60/ADM为研究对象,探讨IC20浓度雷公腾内酯(triptolide,TPL)能否提高ADM诱导耐药白血病细胞凋亡及其与Nrf2通路的关系。方法:流式细胞仪检测空白对照组、IC20浓度TPL单药组、ADM单药组和TPL联合ADM组处理HL-60/ADM后细胞凋亡率;实时荧光定量PCR检测各个处理组作用后,Nrf2及其下游基因醌氧化还原酶(quinone oxidoreductase,NQO1)、谷胱甘肽还原酶(glutathione reductase,GSR)及血红素加氧酶1(heme oxygenase 1,HO-1)的表达水平变化;蛋白质印迹法检测各处理组作用后Nrf2蛋白表达变化。结果:TPL单药组细胞凋亡率为(5.28±0.80)%,与空白对照组的(7.09±0.46)%比较差异无统计学意义,P=0.226;但该浓度TPL可使ADM组细胞凋亡率由(19.55±1.70)%提高到(72.62±4.83)%,是ADM单药组的3.71倍,P〈0.001。空白对照组、TPL单药组、ADM单药组及双药联合组Nrf2mRNA表达水平分别为1、0.742±0.052、0.619±0.042和0.241±0.010,NQO1分别为1、0.363±0.075、0.228±0.053和0.050±0.034;GSR分别为1、0.268±0.042、0.231±0.106和0.038±0.017;HO-1分别为1、0.495±0.023、0.282±0.099和0.048±0.036;各用药组Nrf2及其下游基因NQO1、GSR及HO-1的mRNA表达水平较对照组均出现显著下调,P〈0.001;其中双药联合组下调程度最大。蛋白质印迹法结果显示,用药组及联合组Nrf2表达水平较对照组均有不同程度下调,其中联合组下调最为明显。结论:IC20浓度雷公腾内酯可显著提高ADM诱导耐药白血病细胞凋亡,其分子机制与下调Nrf2通路有关。  相似文献   
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