Congenital Microtia

先天性小生症
  • 文章类型: Journal Article
    目的:几十年来,外耳重建一直是整形外科医生的挑战性课题。使用自体肋软骨或聚乙烯的流行方法仍然有其缺点。随着三维(3D)打印技术的进步,使用合成聚合物的生物支架工程作为替代方案引起了人们的注意。这是一项使用3D打印支架重建耳朵的临床试验,1年后的临床结果。
    方法:从2021年到2022年,五名单侧小耳畸形的成年患者使用3D打印植入物进行了两阶段全耳重建。对于每个病人来说,基于计算机断层扫描图像,使用聚己内酯(PCL)设计并生产了患者特定的3D打印支架,使用熔融沉积建模。术前获得计算机断层扫描,手术后2周内和1年后,比较正常侧和重建耳朵的体积。在为期一年的访问中,由两名外科医生和患者自己拍摄临床照片进行评分。
    结果:在1年的随访中,所有5例患者的耳朵完全愈合。平均而言,重建耳的体积是正常侧耳的161.54%。在0到10的范围内,客观评估者的评分为3到6,而患者的评分为8到10。
    结论:使用3D打印的PCL植入物进行外耳重建显示出持久,安全结果反映在术后1年出色的容量恢复和患者满意度.预计会有更多病例的进一步临床随访,并通过先进的生物打印技术改善支架。该研究的计划和结果已在临床研究信息服务处注册(CRIS编号。3-2019-0306)和食品药品安全部(MFDSNo.1182).
    OBJECTIVE: External ear reconstruction has been a challenging subject for plastic surgeons for decades. Popular methods using autologous costal cartilage or polyethylene still have their drawbacks. With the advance of three-dimensional (3D) printing technique, bioscaffold engineering using synthetic polymer draws attention as an alternative. This is a clinical trial of ear reconstruction using 3D printed scaffold, presented with clinical results after 1 year.
    METHODS: From 2021 to 2022, five adult patients with unilateral microtia underwent two-staged total ear reconstruction using 3D printed implants. For each patient, a patient-specific 3D printed scaffold was designed and produced with polycaprolactone (PCL) based on computed tomography images, using fused deposition modeling. Computed tomography scan was obtained preoperatively, within 2 weeks following the surgery and after 1 year, to compare the volume of the normal side and the reconstructed ear. At 1-year visit, clinical photo was taken for scoring by two surgeons and patients themselves.
    RESULTS: All five patients had completely healed reconstructed ear at 1-year follow-up. On average, the volume of reconstructed ear was 161.54% of that of the normal side ear. In a range of 0 to 10, objective assessors gave scores 3 to 6, whereas patients gave scores 8 to 10.
    CONCLUSIONS: External ear reconstruction using 3D printed PCL implant showed durable, safe results reflected by excellent volume restoration and patient satisfaction at 1 year postoperatively. Further clinical follow-up with more cases and refinement of scaffold with advancing bioprinting technique is anticipated. The study\'s plan and results have been registered with the Clinical Research Information Service (CRIS No. 3-2019-0306) and the Ministry of Food and Drug Safety (MFDS No. 1182).
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  • 文章类型: Journal Article
    目的:当前的研究采用了颅骨模拟器验证方法来评估制造商默认设置下的软带骨传导听力设备(BCHD)的输出是否与拟合公式确定的目标有很大偏差。
    背景:实耳分析用于验证各种机构中的空气传导听力设备(ACHD)的装配。这个程序,然而,尚未用于BCHD的装配,很大程度上是由于测试这些设备输出到颞骨的难度。尽管有头骨模拟器,它们尚未用于临床测量BCHD输出。
    方法:这种前瞻性,单中心研究纳入42名受试者,3个月至10岁,与小耳畸形闭锁相关的轻度至重度双侧传导性听力损失。通过纯音测听法(PTA)对22名4岁或以上的受试者(PTA组)进行行为评估,以及20名年龄小于4岁的受试者(ABR组)的听觉脑干反应(ABR)。在受试者佩戴规定的软带BCHD6个月后,在使用自己的BCHD时重新评估了他们的拨号水平(DL)阈值,在所有频率上配置为零增益,仅用作骨骼振动器。这些DL阈值被输入到拟合公式中,儿童所需的感觉水平骨传导设备(DSL-BCD),获取BCHD输出的目标值。在制造商默认设置下编程的BCHD的模拟器输出响应于在55、65和80dBSPL下呈现的语音进行测量,然后根据模拟器输出和目标之间的差异进行增益调整。在增益调整之前和之后测量辅助语音清晰度指数(SII)。
    结果:制造商设置下的软带BCHD的输出通常低于规定的目标值。这种差异在低频率和低水平下更大。在12个测试点(从500到4000Hz的四个频率乘以三个级别),22(52.3%)和42(100%)BCHD的偏差为+7和+5dB,分别,在一个点或更多。增益调整减小了偏差并改善了所呈现的两个较低语音级别处的SII值。
    结论:具有制造商设置的软带骨传导听力设备(BCHD)的模拟器输出可能会显示出与公式的显着偏差。客观输出验证应被视为BCHD拟合的有益步骤,并在适用时推荐。
    OBJECTIVE: The current study employed a skull-simulator verification method to assess whether the output of softband bone conduction hearing devices (BCHDs) at the manufacturer\'s default settings deviated widely from the target determined by the fitting formula.
    BACKGROUND: Real ear analysis is utilized for the verification of the fitting of air conduction hearing devices (ACHDs) in a variety of institutions. This procedure, however, has not been used in the fitting of BCHDs, largely due to the difficulty of testing the output of these devices to temporal bones. Despite the availability of skull simulators, they have not been utilized clinically to measure BCHD output.
    METHODS: This prospective, single-center study enrolled 42 subjects, aged 3 months to 10 years, with microtia-atresia-associated mild-to-severe bilateral conductive hearing loss. Hearing sensitivity was evaluated behaviorally by pure tone audiometry (PTA) in 22 subjects 4 years or older (the PTA group), and by auditory brainstem response (ABR) in 20 subjects younger than 4 years (the ABR group). Following 6 months of subjects wearing the prescribed softband BCHDs, their dial level (DL) thresholds were reassessed while using their own BCHDs, configured with zero gain across all frequencies, functioning solely as a bone vibrator. These DL thresholds were inputted into the fitting formula, desired sensation level-bone conduction devices (DSL-BCD) for children, to obtain the target values of BCHD output. The simulator output of the BCHD programmed at the manufacturer\'s default setting was measured in response to speech presented at 55, 65, and 80 dB SPL, followed by gain adjustment based on the differences between the simulator output and the target. Aided speech intelligibility index (SII) was measured before and after the gain adjustment.
    RESULTS: The softband BCHDs at the manufacturer\'s settings generally had lower output than the prescribed target values. This difference was larger at low frequencies and low levels. Across the 12 points tested (four frequencies from 500 to 4000 Hz multiplied by three levels), 22 (52.3%) and 42 (100%) BCHDs had deviations of +7 and +5 dB, respectively, at one point or more. The gain adjustments reduced the deviation and improved the SII values at the two lower levels of speech presented.
    CONCLUSIONS: The simulator output of softband bone conduction hearing devices (BCHDs) with the manufacturer\'s settings may exhibit significant deviations from the formula. Objective output verification should be considered a beneficial step in BCHD fitting and is recommended when applicable.
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  • 文章类型: Letter
    暂无摘要。
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  • 文章类型: Journal Article
    Complex ear reconstruction requires specialized multidisciplinary care. Most patients present with microtia, often associated with hearing disorders. The management of these disorders is a priority, and reconstruction of the external ear remains optional. Nowadays, auricular reconstruction is based on the subcutaneous implantation of either autologous cartilage or an allogeneic implant. Autologous reconstruction requires highly specialized surgical expertise and involves harvesting rib cartilage but carries a lower risk of exposure compared to allogeneic implants. Both techniques yield good results with a high success rate and have a positive impact on the social functioning and daily life of patients.
    La reconstruction complexe du pavillon auriculaire nécessite une prise en charge multidisciplinaire spécialisée. La majorité des patients nécessitant ce geste présentent une microtie, souvent associée à des troubles de l’audition. La prise en charge de ceux-ci est prioritaire et la reconstruction du pavillon reste facultative. Aujourd’hui, la reconstruction du pavillon se base sur l’implantation sous-cutanée d’une maquette de cartilage autologue ou d’un implant allogène. La reconstruction autologue demande une expertise chirurgicale hautement spécialisée et nécessite un prélèvement de cartilage costal mais présente un risque d’exposition inférieur par rapport à l’implant allogène. Les deux techniques permettent d’atteindre de bons résultats avec un taux de réussite élevé et un effet positif sur le fonctionnement social et le quotidien des patients.
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  • 文章类型: Journal Article
    人的耳廓有着复杂的结构,小耳畸形是一种先天性畸形,其特征是受影响的耳朵中尺寸减小和复杂结构的丢失,发病率很高。我们以前的研究表明,细胞迁移不足是小视体发病的主要细胞学基础,然而,潜在机制尚不清楚.这里,我们进一步证明了小耳软骨细胞在细胞迁移过程中显示出降低的定向持久性。定向持久性可以定义与定向运动相关的前沿,任何错误都会影响细胞功能和组织形态。通过对运动性相关基因的筛选和后续的确认,活性Rac1(Rac1-GTP)被确定为对于微耳软骨细胞迁移的定向持久性受损至关重要。此外,检测到Rho鸟嘌呤核苷酸交换因子(GEF)和RhoGTPase激活蛋白(GAP),Tiam1的过表达显着上调Rac1-GTP的水平并改善小耳软骨细胞的定向迁移。始终如一,Tiam1和活性Rac1的表达模式在小耳小鼠模型中发现,Bmp5se/J和Prkralear-3J/GrsrJ。总的来说,我们的研究结果为小耳畸形患者的小耳发育和组织工程治疗策略提供了新的见解。
    The human auricle has a complex structure, and microtia is a congenital malformation characterized by decreased size and loss of elaborate structure in the affected ear with a high incidence. Our previous studies suggest that inadequate cell migration is the primary cytological basis for the pathogenesis of microtia, however, the underlying mechanism is unclear. Here, we further demonstrate that microtia chondrocytes show a decreased directional persistence during cell migration. Directional persistence can define a leading edge associated with oriented movement, and any mistakes would affect cell function and tissue morphology. By the screening of motility-related genes and subsequent confirmations, active Rac1 (Rac1-GTP) is identified to be critical for the impaired directional persistence of microtia chondrocytes migration. Moreover, Rho guanine nucleotide exchange factors (GEFs) and Rho GTPase-activating proteins (GAPs) are detected, and overexpression of Tiam1 significantly upregulates the level of Rac1-GTP and improves directional migration in microtia chondrocytes. Consistently, decreased expression patterns of Tiam1 and active Rac1 are found in microtia mouse models, Bmp5se/J and Prkralear-3J/GrsrJ. Collectively, our results provide new insights into microtia development and therapeutic strategies of tissue engineering for microtia patients.
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  • 文章类型: Journal Article
    背景:胸部畸形是使用自体肋软骨重建耳廓的潜在并发症。用于获取肋软骨的切口大小对胸部畸形的影响尚不清楚。本研究旨在探讨用于获取肋软骨的切口大小与胸部畸形发生的相关性。
    方法:我们回顾性分析了2021年6月至2022年9月期间使用自体肋软骨进行耳部重建的患者。根据肋软骨切口的大小将患者分为两组:大和小。术后18-24个月行胸部计算机断层扫描(CT),然后进行三维彩色图定量,以评估胸部表面的不对称程度。随后,我们进行了定量数据分析,以比较大切口组和小切口组的胸部不对称程度.视觉模拟量表(VAS)用于评估患者对胸部形态的满意度。
    结果:本研究包括62名患者,每组31个相等的分布。小切口组和大切口组的平均不对称值分别为-3.15±1.88和-5.27±3.63。此外,小切口组和大切口组的平均VAS评分分别为7.48±0.72和5.09±0.94.两组间差异有统计学意义。
    结论:小切口获取肋软骨能有效缓解胸部畸形的严重程度,显著提高患者满意度。
    方法:本期刊要求作者为每篇文章分配一定程度的证据。对于这些循证医学评级的完整描述,请参阅目录或在线作者说明www。springer.com/00266.
    BACKGROUND: Chest deformity is a potential complication associated with auricular reconstruction using autologous costal cartilage. The impact of the incision size employed for costal cartilage harvesting on chest deformities remains unclear. This study aimed to investigate the correlation between the incision size used for harvesting costal cartilage and the occurrence of chest deformities.
    METHODS: We retrospectively analyzed patients who underwent ear reconstruction using autologous costal cartilage between June 2021 and September 2022. The patients were categorized into two groups based on the size of the costal cartilage incision: large and small. Chest computed tomography (CT) was performed 18-24 months postoperatively, followed by three-dimensional color map quantification to assess the degree of asymmetry of the chest surface. Subsequently, quantitative data analysis was performed to compare the extent of chest asymmetry between the large- and small-incision groups. The Visual Analog Scale (VAS) was used to assess patient satisfaction with chest morphology.
    RESULTS: This study included 62 patients, with an equal distribution of 31 in each group. The mean asymmetry value of the small and large incision groups was -3.15 ± 1.88 and -5.27 ± 3.63, respectively. Moreover, the mean VAS score for the small and large incision groups was 7.48 ± 0.72 and 5.09 ± 0.94, respectively. Statistically significant differences were observed between the two groups.
    CONCLUSIONS: Small incision costal cartilage harvesting can effectively alleviate the severity of chest deformities and significantly enhance patient satisfaction.
    METHODS: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .
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  • 文章类型: Journal Article
    背景:据报道,小骨症是最常见的先天性颅面畸形之一。由于复杂的病因和胚胎研究的伦理障碍,微小症的确切机制尚不清楚。在这里,我们根据生物信息学分析和对其他散发性小虫患者的进一步验证,报告了一例罕见的小虫伴肋骨软骨发育不良的病例。
    结果:通过WES筛选出114个有害插入和缺失(InDel)和646个有害SNP,候选基因根据它们与microtia的相对影响按降序排列。无标记蛋白质组分析表明,各组间蛋白质差异显著,与氧化应激和能量代谢有关。通过实时PCR和免疫组织化学,我们进一步验证了其他散发性小耳和正常耳软骨细胞之间的候选基因,显示苏氨酸天冬氨酸酶,cadherin-13,醛缩酶B和脂联素在mRNA水平上显着上调,但在蛋白质水平上显着降低。ROS检测和线粒体膜电位(ΔΦm)检测证明,小耳软骨细胞中存在氧化应激。
    结论:我们的结果不仅通过WES和无标记蛋白质组学发现了新的候选基因,但也首次推测代谢和氧化应激可能会干扰软骨发育,这可能成为治疗靶点和潜在的生物标志物,在未来具有临床应用价值。
    BACKGROUND: Microtia is reported to be one of the most common congenital craniofacial malformations. Due to the complex etiology and the ethical barrier of embryonic study, the precise mechanisms of microtia remain unclear. Here we report a rare case of microtia with costal chondrodysplasia based on bioinformatics analysis and further verifications on other sporadic microtia patients.
    RESULTS: One hundred fourteen deleterious insert and deletion (InDel) and 646 deleterious SNPs were screened out by WES, candidate genes were ranked in descending order according to their relative impact with microtia. Label-free proteomic analysis showed that proteins significantly different between the groups were related with oxidative stress and energy metabolism. By real-time PCR and immunohistochemistry, we further verified the candidate genes between other sporadic microtia and normal ear chondrocytes, which showed threonine aspartase, cadherin-13, aldolase B and adiponectin were significantly upregulated in mRNA levels but were significantly lower in protein levels. ROS detection and mitochondrial membrane potential (∆ Ψ m) detection proved that oxidative stress exists in microtia chondrocytes.
    CONCLUSIONS: Our results not only spot new candidate genes by WES and label-free proteomics, but also speculate for the first time that metabolism and oxidative stress may disturb cartilage development and this might become therapeutic targets and potential biomarkers with clinical usefulness in the future.
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  • 文章类型: Systematic Review
    背景:自体肋软骨已被广泛接受为小骨症患者耳部重建的重要材料。尽管它被认为“值得权衡”,“应注意供体部位的畸形。本系统综述集中于与小骨症重建相关的现有英文文献,旨在揭示胸壁畸形的发生率,并评估旨在减少供体部位发病率的各种拟议外科技术的有效性。
    方法:使用关键字\"microtia,\"和\"胸部畸形\"或\"肋骨收获。“根据预定义的纳入和排除标准筛选文章。数据采集包括患者人口统计学,采用手术技术,评估胸部畸形的方法,以及相关并发症的发生率。
    结果:在362篇确定的文章中,21符合纳入标准。本综述共分析2600例,涉及2433例小耳畸形患者。软骨收获过程中的软骨膜保存导致胸部畸形的显着减少。然而,广泛的发病率范围(0%~50%)和缺乏具体的评估方法提示潜在的低估.计算机断层扫描显示胸壁在横向和矢状方向的生长减少,导致胸部面积减少。创新的手术技术在减少胸部畸形方面显示出了有希望的结果。
    结论:尽管定量分析不可行,通过计算机断层扫描建立了畸形的客观证据.该分析强调了需要进行更大样本量的专门研究,以进一步增进我们对小骨症重建中胸壁畸形的理解。
    BACKGROUND: Autologous costal cartilage has gained widespread acceptance as an important material for ear reconstruction in patients with microtia. Despite its recognition as being \"worth the trade-off,\" attention should be directed toward donor-site deformities. This systematic review focused on existing English literature related to microtia reconstruction and aimed to reveal the incidence of chest wall deformities and assess the effectiveness of the various proposed surgical techniques aimed at reducing donor-site morbidities.
    METHODS: A comprehensive search was conducted on Pubmed and OVID using the keywords \"microtia,\" and \"chest deformity\" or \"rib harvest.\" Articles were screened based on predefined inclusion and exclusion criteria. Data acquisition encompassed patient demographics, employed surgical techniques, methods for evaluating chest deformity, and incidence of associated complications.
    RESULTS: Among the 362 identified articles, 21 met the inclusion criteria. A total of 2600 cases involving 2433 patients with microtia were analyzed in this review. Perichondrium preservation during cartilage harvesting led to a significant reduction in chest deformities. However, the wide incidence range (0% to 50%) and the lack of specific assessment methods suggested potential underestimation. Computed tomography revealed reduced chest wall growth in the transverse and sagittal directions, resulting in decreased thoracic area. Innovative surgical techniques have shown promising results in reducing chest deformities.
    CONCLUSIONS: Although a quantitative analysis was not feasible, objective evidence of deformities was established through computed tomography scans. This analysis highlighted the need for dedicated studies with larger sample sizes to further advance our understanding of chest wall deformities in microtia reconstruction.
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  • 文章类型: Journal Article
    Meier-Gorlin综合征(MGORS)是一种常染色体隐性遗传疾病,以身材矮小为特征,microtia,髌骨发育不全,并且是由参与DNA复制起始的细胞因子的致病变体引起的。我们先前报道了GINS3中的双等位基因变体导致第24位的氨基酸变化(p。Asp24)引起MGORS。这里,我们描述了Asp24Asn变体的新纯合个体的表型。我们还报告了具有新型纯合GINS3变体(Ile25Phe)的个体的临床特征和提示MGORS的特征。与人源化Psf3Val9Ile变体相比,酵母Psf3(Val9Phe)中相应残基的修饰损害了S期进展。Psf3Val9Phe在酵母中的表达也引起了对高温和复制性应激诱导药物羟基脲的敏感性,确认该变体在体内的部分功能丧失,并允许我们升级该变体的分类。一起来看,这些数据证实了GINSDNA复制复合物在MGORS分子病因中的重要意义.
    Meier-Gorlin syndrome (MGORS) is an autosomal recessive disorder characterized by short stature, microtia, and patellar hypoplasia, and is caused by pathogenic variants of cellular factors involved in the initiation of DNA replication. We previously reported that biallelic variants in GINS3 leading to amino acid changes at position 24 (p.Asp24) cause MGORS. Here, we describe the phenotype of a new individual homozygous for the Asp24Asn variant. We also report the clinical characteristics of an individual harboring a novel homozygous GINS3 variant (Ile25Phe) and features suggestive of MGORS. Modification of the corresponding residue in yeast Psf3 (Val9Phe) compromised S phase progression compared to a humanized Psf3 Val9Ile variant. Expression of Psf3 Val9Phe in yeast also caused sensitivity to elevated temperature and the replicative stress-inducing drug hydroxyurea, confirming partial loss of function of this variant in vivo and allowing us to upgrade the classification of this variant. Taken together, these data validate the critical importance of the GINS DNA replication complex in the molecular etiology of MGORS.
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  • 文章类型: Journal Article
    目的:本文比较了人口统计,形态学,功能,以及厄瓜多尔混血儿患者中孤立型和家族型小虫的危险因素。
    方法:作者做了流行病学研究,并对112例患者进行了回顾性研究,分为孤立的小团体(n=91)和家族性小团体(n=21)。综合征性小耳畸形患者不包括在内。
    结果:在孤立的小视体中,平均年龄为11.80±16.9岁,最普遍的年龄组为5至9岁,占45.0%;男性占58.2%,91.2%的患者出生在海拔2500米以上的城市。在家族性小生中,平均年龄为15.57±17.2。所分析的变量之间没有统计学上的显著差异。在孤立的小团体中,41.8%的患者有双侧受累,40.7%的人右耳有1级小耳畸形(RE),左耳1级占47.3%;外耳道闭锁占62.6%,左耳占31.6%。两组的外耳道闭锁侧均为单侧。大多数患者没有标记或凹坑(RE分别为78%和81%,85.7%和71.4%)。大多数患者的两只耳朵都有中度听力损失。
    结论:作者发现两种小耳畸形与RE中的外耳道闭锁之间存在关联;两组中只有20%的患者有单侧耳廓标记或凹陷。作者还发现家族性小耳症的发病率很高(18.75%),这表明与更普遍的孤立病例相比,有明显的病理遗传成分。作者发现,来自海拔2500米(超过90%)的厄瓜多尔高地的微小症病例具有很高的相关性。怀孕期间“社会”酒精摄入量的存在表明,生下患有小耳畸形的孩子的机会超过两倍。
    OBJECTIVE: This paper compares demographic, morphological, functional, and risk factors between isolated and familial forms of microtia in Ecuadorian mestizo patients.
    METHODS: The authors did an epidemiological, and retrospective study with 112 patients divided into isolated microtia (n = 91) and familial microtia (n = 21). Patients with syndromic microtia were not included.
    RESULTS: In isolated microtia, the mean age was 11.80 ± 16.9, and the most prevalent age group was from 5 to 9 years, with 45.0%; males were 58.2%, and 91.2% of patients were born in a city above 2500 meters about sea level. In familial microtia, the mean age was 15.57 ± 17.2. There were no statistically significant differences between the analyzed variables. In isolated microtia, 41.8% of patients had bilateral involvement, 40.7% had grade 1 microtia in the right ear (RE), and grade 1 in the left ear was 47.3%; external auditory canal atresia of RE was present in 62.6%, and in left ear in 31.6%. External auditory canal atresia sidedness was mostly unilateral in both groups. Most patients did not have tags or pits (78% and 81% in RE and 85.7% and 71.4%). Most patients had moderate hearing loss in both ears.
    CONCLUSIONS: The authors found an association between both microtia forms with external auditory canal atresia in RE; only 20% of patients had unilateral auricular tags or pits in both groups. The authors also found a high incidence (18.75%) of familial microtia, which suggests a distinct pathological genetic component than the more prevalent isolated cases. The authors found a high association of microtia cases from the Ecuadorian highlands above 2500 meters about sea level (over 90%). The presence of \"social\" intake of alcohol during pregnancy showed over twice the chance of having a child born with microtia.
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