Living biobank-based cancer organoids: prospects and challenges in cancer research

Biobanks bridge the gap between basic and translational research. Traditional cancer biobanks typically contain normal and tumor tissues, and matched blood. However, biospecimens in traditional biobanks are usually nonrenewable. In recent years, increased interest has focused on establishing living biobanks, including organoid biobanks, for the collection and storage of viable and functional tissues for long periods of time. The organoid model is based on a 3D in vitro cell culture system, is highly similar to primary tissues and organs in vivo, and can recapitulate the phenotypic and genetic characteristics of target organs. Publications on cancer organoids have recently increased, and many types of cancer organoids have been used for modeling cancer processes, as well as for drug discovery and screening. On the basis of the current research status, more exploration of cancer organoids through technical advancements is required to improve reproducibility and scalability. Moreover, given the natural characteristics of organoids, greater attention must be paid to ethical considerations. Here, we summarize recent advances in cancer organoid biobanking research, encompassing rectal, gastric, pancreatic, breast, and glioblastoma cancers. Living cancer biobanks that contain cancerous tissues and matched organoids with different genetic backgrounds, subtypes, and individualized characteristics will eventually contribute to the understanding of cancer and ultimately facilitate the development of innovative treatments.     

Reorganization of brain activity for multiple internal models after short but intensive training

Internal models are neural mechanisms that can mimic the input-output properties of controlled objects. Our studies have shown that: 1) an internal model for a novel tool is acquired in the cerebellum (Imamizu et al., 2000); 2) internal models are modularly organized in the cerebellum (Imamizu et al., 2003); 3) their outputs are sent to the premotor regions after learning (Tamada et al., 1999); and 4) the prefrontal and parietal regions contribute to the blending of the outputs (Imamizu et al., 2004). Here, we investigated changes in global neural networks resulting from the acquisition of a new internal model. Human subjects manipulated three types of rotating joystick whose cursor appeared at a position rotated 60 degrees, 110 degrees, or 160 degrees around the screen's center. In a pre-test after long-term training (5 days) for the 60 degrees and 160 degrees joysticks, brain activation was scanned during manipulation of the three joysticks. The subjects were then trained for the 110 degrees for only 25 min. In a post-test, activation was scanned using the same method as the pre-test. Comparisons of the post-test to the pre-test revealed that the volume of activation decreased in most of the regions where activation for the three rotations was observed. However, there was an increase in volume at a marginally significant level (p < .08) only in the inferior-lateral cerebellum and only for the 110 degrees joystick. In the cerebral cortex, activation related to 110 degrees decreased in the prefrontal and parietal regions but increased in the premotor and supplementary motor area (SMA) regions. These results can be explained by a model in which outputs of the 60 degrees and 160 degrees internal models are blended by prefrontal and parietal regions to cope with the novel 110 degrees joystick before the 25-minute training; after the acquisition within the cerebellum of an internal model for the 110 degrees, output is directly sent to the premotor and SMA regions, and activation in these regions increases.     

Post-Traumatic Epilepsy: Cellular Mechanisms and Implications for Treatment

Summary: Epilepsy complicates severe head trauma. Development of persistent seizures appears to correlate with the extent of trauma. Although early reports suggested that prophylactic administration of antiepileptic drugs would prevent epileptogenesis, controlled studies have failed to corroborate this assumption. Head trauma initiates a sequence of responses that includes altered blood flow and vasoregulation, disruption of the blood-brain barrier, increases in intracranial pressure, focal or diffuse ischemia, hemorrhage, inflammation, necrosis, and disruption of fiber tracts. The presence of an intracranial hematoma has a robust association with the development of post-traumatic epilepsy. Extravasation of blood is followed by hemolysis and deposition of heme-containing compounds into the neuropil, initiating a sequence of univalent redox reactions and generating various free radical species, including superoxides, hydroxyl radicals, peroxides, and perferryl ions. Free radicals initiate peroxidation reactions by hydrogen abstraction from methylene groups adjacent to double bonds of fatty acids and lipids within cellular membranes. Intrinsic enzymatic mechanisms for control of free radical reactions include activation of catalase, peroxidase, and superoxide dismutase. Steroids, proteins, and tocopherol also terminate per-oxidative reactions. Tocopherol and selenium are effective in preventing tissue injury initiated by ferrous chloride and heme compounds. Treatment strategies for prevention or prophylaxis of post-traumatic epilepsy must await absolute knowledge of mechanisms. Antioxidants and chelators may be useful, given the speculation that peroxidative reactions may be an important component of brain injury responses. However, potential treatment strategies involving -y-aminobutyric acid (GABA) agonists, NMDA receptor antagonists, and barbiturates need further scientific assessment.     

Population Size Estimation From Capture-Recapture Studies Using shinyrecap: Design and Implementation of a Web-Based Graphical User Interface

BackgroundPopulation size estimates (PSE) provide critical information in determining resource allocation for HIV services geared toward those at high risk of HIV, including female sex workers, men who have sex with men, and people who inject drugs. Capture-recapture (CRC) is often used to estimate the size of these often-hidden populations. Compared with the commonly used 2-source CRC, CRC relying on 3 (or more) samples (3S-CRC) can provide more robust PSE but involve far more complex statistical analysis.ObjectiveThis study aims to design and describe the Shiny application (shinyrecap), a user-friendly interface that can be used by field epidemiologists to produce PSE.Methodsshinyrecap is built on the Shiny web application framework for R. This allows it to seamlessly integrate with the sophisticated CRC statistical packages (eg, Rcapture, dga, LCMCR). Additionally, the application may be accessed online or run locally on the user’s machine.ResultsThe application enables users to engage in sample size calculation based on a simulation framework. It assists in the proper formatting of collected data by providing a tool to convert commonly used formats to that used by the analysis software. A wide variety of methodologies are supported by the analysis tool, including log-linear, Bayesian model averaging, and Bayesian latent class models. For each methodology, diagnostics and model checking interfaces are provided.ConclusionsThrough a use case, we demonstrated the broad utility of this powerful tool with 3S-CRC data to produce PSE for female sex workers in a subnational unit of a country in sub-Saharan Africa.     

单侧椎弓根钉内固定建立新型山羊脊柱侧凸模型的实验研究

目的探讨未成年山羊脊柱单侧椎弓根钉内固定并对侧肋骨切除建立新型脊柱侧凸模型的可行性。方法实验对象为14只雌性山羊,年龄5~8周,体重6~8kg。在全麻下进行模型制作,T5~L2做右旁正中皮肤切口,分别于脊柱左侧T6,7和T12、L1部位置入特制椎弓根螺钉,经皮下及肌肉下插入1枚不锈钢棒置入螺钉槽口内,远近端螺钉之间适当加压使脊柱向右凸;然后于脊柱右侧分别切除第7~12肋骨2~3cm左右。术后即刻及每4周拍摄正侧位X线片,观察山羊在生长过程中脊柱弯曲的变化。结果1只小羊因麻醉过量,术中死亡;另1只因术后感染而导致内固定失败,观察终止。其余12只小羊中,11只小羊X线片显示右侧侧凸畸形,并且Cobb角随时间延长而增大。只有1只羊术后Cobb角没有进展。术后即刻Cobb角平均为29.0°(23.0°~38.5°),8~10周后Cobb角增至平均43.0°(36.0°~58.0°),平均进展14.0°。术后8周(1只为10周)时获取脊柱标本,去除内固定后发现所有弯曲均为结构性。从脊椎的旋转和外观方面来看,均与特发性脊柱侧凸畸形相似。结论单侧椎弓根钉内固定是一种比较可靠的建立脊柱侧凸模型的方法,模型与特发性脊柱侧凸相似,适用于脊柱侧凸畸形的实验研究。     

通窍化瘀法对大鼠视网膜血管内皮和视神经放射性损伤的预防作用

【目的】探讨通窍化瘀法对大鼠视网膜血管内皮细胞和视神经放射性损伤的预防作用。【方法】选择SD大鼠36只,随机分为空白组、模型组和实验组,模型组与实验组均采用放射线照射3周,每周1次;实验组于放射照射前2周开始每日腹腔内注射黄芪注射液（剂量为4.0 g/kg）、盐酸川芎嗪注射液（剂量为15 mg/kg）和醒脑静注射液（剂量为2.5 mL/kg）,空白组和模型组每日腹腔注射等量生理盐水。采用酶联免疫吸附（ELISA）法测定各组放射照射前、照射后1 d、2周、4周及6周大鼠静脉血内皮素-1（ET-1）和血管性血友病因子(vWF)的浓度,分析其动态变化和组间差异。于照射后2、4、6周分别取材进行视神经透射电镜检查,观察视神经轴索脱髓鞘病变程度,并计算和比较各组视神经脱髓鞘率。【结果】与空白组比较,放射照射后模型组静脉血ET-1、 vWF浓度显著升高,差异均有统计学意义（P＜0.05）,并于照射后4周达到峰值;与模型组比较,照射2周后实验组静脉血ET-1、 vWF浓度显著降低,差异均有统计学意义（P＜0.05）;与空白组比较,放射照射后2、4、6周模型组视神经脱髓鞘率显著增高,差异均有统计学意义（P＜0.05）;模型组和实验组比较视神经脱髓鞘率在照射后2、4周差异均无统计学意义（P＞0.05）,照射后6周实验组视神经脱髓鞘率显著低于模型组,差异有统计学意义（P＜0.05）。【结论】通窍化瘀法预防性干预能够显著降低放射性视网膜视神经损伤模型大鼠静脉血ET-1、 vWF浓度,减轻放射线对视网膜血管内皮的损伤,并对放射性视神经损伤后期轴索脱髓鞘改变有改善作用。     

安心颗粒对血脂紊乱家兔血脂及主动脉超微结构的影响

目的:研究安心颗粒对家兔实验性血脂紊乱的防治作用.方法:采用食饵性血脂紊乱新西兰家兔为模型,以脂必妥片为对照药,观察安心颗粒对血脂、主动脉超微结构的影响.将32只新西兰家兔随机分为正常对照组、模型组、脂必妥片组、安心颗粒组等4组,分别给予普通饲料、高脂饲料、高脂饲料加脂必妥片、高脂饲料加安心颗粒.10周后,测定各组动物血清总胆固醇(total cholesterol,TC)、甘油三酯(triglycerides,TG)、低密度脂蛋白胆固醇(low density lipoprotein cholesterol,LDL-C)、高密度脂蛋白胆固醇(high density lipoprotein cholesterol,HDL-C)、载脂蛋白A1(apolipoprotein A1,ApoA1)、载脂蛋白B(apolipoprotein B,ApoB)水平,同时用电镜观察主动脉超微结构.结果:安心颗粒可以显著降低血脂紊乱新西兰兔血清TC、TG、LDL-C、ApoB水平;电镜下主动脉超微结构观察显示:安心颗粒组主动脉硬化病变较模型组和脂必妥片组轻,血管内皮细胞质内偶见小脂滴空泡,各种细胞器存在,内弹力膜存在,中层平滑肌细胞质内无脂滴空泡.结论:安心颗粒能调节兔的血脂代谢,对动脉粥样硬化病变有明显的抑制作用.     

Immunotoxin Against a Donor MHC Class II Molecule Induces Indefinite Survival of Murine Kidney Allografts

Rejection of donor organs depends on the trafficking of donor passenger leukocytes to the secondary lymphoid organs of the recipient to elicit an immune response via the direct antigen presentation pathway. Therefore, the depletion of passenger leukocytes may be clinically applicable as a strategy to improve graft survival. Because major histocompatibility complex (MHC) class II⁺ cells are most efficient at inducing immune responses, selective depletion of this population from donor grafts may dampen the alloimmune response and prolong graft survival. In a fully MHC mismatched mouse kidney allograft model, we describe the synthesis of an immunotoxin, consisting of the F(ab′)₂ fragment of a monoclonal antibody against the donor MHC class II molecule I‐A^k conjugated with the plant‐derived ribosomal inactivating protein gelonin. This anti–I‐A^k gelonin immunotoxin depletes I‐A^k expressing cells specifically in vitro and in vivo. When given to recipients of kidney allografts, it resulted in indefinite graft survival with normal graft function, presence of Foxp3⁺ cells within donor grafts, diminished donor‐specific antibody formation, and delayed rejection of subsequent donor‐type skin grafts. Strategies aimed at the donor arm of the immune system using agents such as immunotoxins may be a useful adjuvant to existing recipient‐orientated immunosuppression.     

合成氨系统优化的一类新方法

本文介绍一类新的优化方法及其在合成氨系统上应用的例子。该大系统分解-协调方法可方便地处理高阶系统。由计算机仿真对给定值进行调整,经实验验证,结果满意。文中并对在线计算机控制方案进行了探讨。     

SHH基因转染BMMSC心肌移植对大鼠心肌梗死后血管新生的影响

目的探讨SHH（Sonic hedgehog）基因转染的骨髓间充质干细胞（BMMSCSHH）移植对大鼠心肌梗死区移植部位血管再生的影响。方法密度梯度离心法及贴壁培养获得BMMSC后,电转染法将SHH基因转入骨髓间充质干细胞。以结扎法制备大鼠急性心肌梗死模型,将实验动物200只大鼠按随机数字表法分5组,每组40只;分别在梗死与正常交界部位移植BMMSCSHH（转染组）、等量的BMMSC（细胞组）、pcDNA3．1-ShhDNA（基因组）、BMMSC和pcDNA3．1-ShhDNA的混合物（混合组）、等容积的低糖DMEM培养基（对照组）。于移植后第8周取正常心肌与心肌梗死交界区组织标本行免疫组化染色标记血管,通过血管密度分析法分析各组间交界区血管密度差异。结果经CD34免疫组化染色后行血管密度分析显示：转染组（36．48±5．22）较对照组（16．71±3．41）血管密度增加（P〈0．01）;较细胞组（29．46±2．27）、基因组（28．78±2．91）及混合组（29．55±4．55）血管密度增加（P〈0．05）。结论BMMSCSHH移植能有效表达目的基因、促进心肌梗死后血管新生,为缺血性心脏病的细胞转基因治疗提供理论依据。