Arterial spin labeling MR image denoising and reconstruction using unsupervised deep learning

Arterial spin labeling (ASL) imaging is a powerful magnetic resonance imaging technique that allows to quantitatively measure blood perfusion non-invasively, which has great potential for assessing tissue viability in various clinical settings. However, the clinical applications of ASL are currently limited by its low signal-to-noise ratio (SNR), limited spatial resolution, and long imaging time. In this work, we propose an unsupervised deep learning-based image denoising and reconstruction framework to improve the SNR and accelerate the imaging speed of high resolution ASL imaging. The unique feature of the proposed framework is that it does not require any prior training pairs but only the subject's own anatomical prior, such as T1-weighted images, as network input. The neural network was trained from scratch in the denoising or reconstruction process, with noisy images or sparely sampled k-space data as training labels. Performance of the proposed method was evaluated using in vivo experiment data obtained from 3 healthy subjects on a 3T MR scanner, using ASL images acquired with 44-min acquisition time as the ground truth. Both qualitative and quantitative analyses demonstrate the superior performance of the proposed txtc framework over the reference methods. In summary, our proposed unsupervised deep learning-based denoising and reconstruction framework can improve the image quality and accelerate the imaging speed of ASL imaging.     

医学信息工程专业导论课程设计与实施

为了提高学生对医学信息工程专业的专业定位、培养目标及专业发展方向等的认知程度。结合教学改革的需要,从教学目标、教学内容、教学策略和方法以及形成性评价等方面探讨了专业导论课的课程设计、实施和课程评价。结果显示,医学信息工程专业导论课受到了学生的高度认可,开设导论课是非常有必要的。     

天麻素生物合成的研究进展

天麻素是我国名贵中药材天麻中的一种主要活性成分，具有降血压、抗癫痫、抑制肿瘤、保护神经等多方面的药理活性。随着市场对天麻素需求的不断增长以及传统获取方法固有的问题，导致急需新的方法来解决天麻素生产实际中面临的各项困难。生物合成法是一种有别于传统获取法的新方法，已在天麻素获取上取得了较大进展和成果，故现阶段有必要从天麻素生物合成途径、植物转化法和微生物转化法3个方面，对天麻素生物合成进行系统地阐述，从而为进一步改进和完善天麻素生产方法，以满足人们对其不断增长的需求提供有价值的参考。     

美国新药技术成熟度评价研究

目的研究提出适合我国新药研发和药品安全管理的技术成熟度评价机制。方法借鉴美国新药研发技术成熟度等级(biomedical technology readiness level,BTRL)评价标准与方法,结合我国新药研发、监管和产业化特点,提出我国成熟度评价等级和指标,并在重大新药创制科技重大专项研发管理中开展探索分析。结果与结论探索建立我国化学药和生物制品技术成熟度评价等级标准,将为我国新药研发科研项目和保障药品安全提供管理与评估工具,为其他行业领域提供参考借鉴。     

个体化假体复合组织工程技术修复兔下颌骨缺损

目的研究快速成型（RP）技术辅助下制作的个体化假体复合珊瑚羟基磷灰石（CHA）、重组人骨形成蛋白2（rhBMP-2）修复兔下颌骨缺损的成骨效果。 方法以27只新西兰大白兔为实验对象，随机数字表法平均分成3组（每组9只），全部建立下颌骨连续性缺损模型，并在兔下颌骨缺损区分别植入个体化假体+自体骨（A组）、个体化假体+CHA（B组）、个体化假体+CHA+rhBMP-2（C组）。分别于术后4、12、24周3个时间点处死动物取材，进行大体标本观察，以及骨钙素（OC）、Ⅰ型胶原（COL-1）的免疫组化观察，分别比较各组修复骨缺损的能力，并对实验数据进行重复测量设计资料的单因素方差分析。 结果术后24周各组实验兔外形均对称，通过OC及COL-1的吸光度检测，骨缺损区均有大量新骨形成，A组（0.537 ± 0.010）、C组（0.530 ± 0.010）可见大量骨小梁及编织骨结构，缺损区的新骨OC、COL-1的免疫组化观察基本一致，差异无统计学意义（t = 0.007，P>0.05）；但A组强于B组（0.415 ± 0.009，t = 0.122，P<0.001）；C组也强于B组（t = 0.121，P<0.001），差异均有统计学意义。 结论在兔下颌骨缺损修复中，通过RP技术和组织工程技术相结合，CHA复合rhBMP-2后成骨能力明显增强，成骨效能肯定，为后期的临床应用提供可靠的实验基础。     

Stem cells for babies and their surgeons: The future is now

Pediatric surgeons are ideal allies for the translation of basic science including stem cell therapies. In the spirit of Robert E. Gross, of applying creative solutions to pediatric problems with technical expertise, we describe the impending cellular therapies that may be derived from stem and progenitor cells. Understanding the types and capabilities of stem and progenitor cells is important for pediatric surgeons to join and facilitate progress for babies. We are developing an induced pluripotent stem cell therapy for enteric neuropathies such as Hirschsprung disease that might be helpful for children in the near future. Our goals, which we hope to share with other surgeons and scientists, include working to establish safe clinical trials and meeting regulatory standards in a thoughtful way that balances patients need and unknown risks.     

Three-year efficacy and patency follow-up of decellularized human internal mammary artery as a novel vascular graft in animal models

Background

Various investigations have reported that the internal mammary artery (IMA) is an efficient and functional choice of conduit for vascular graft surgeries, especially for coronary artery bypass grafts; however, the quest to find an ideal vascular substitute remains. We hypothesized that acellular IMA could be an appropriate graft for small-diameter vascular bypasses that could be used in various surgeries including coronary artery bypass grafting.