Assessment of Carbendazim Residues and Safety in Celery Under Different Cultivation Conditions

Although the carbendazim is widely used to manage spot blight in celery cultivation, information on residues identified is of interest. In this study, we examined the dissipation and residual amounts of carbendazim in celery and soil under different cultivation methods when using the suggested dose and ten times of that and the bioconcentration factor of carbendazim for celery. The results showed that when celery leaves were sprayed with the suggested dose, the half-lives in a celery field and greenhouse were 2.75 days and 3.29 days, respectively. When the soil matrix was sprayed with the recommended dose before cultivation, the half-lives of carbendazim residues were 16.86 days and 11.97 days. We also conducted a long-term dietary risk assessment using the corresponding criteria. The results showed that, in China, the use of carbendazim at a dose of 0.022 g/m² is safer and more reasonable when the harvest interval is 28 days.

     

正交偏光镜下人体胆汁液晶光学性质的研究

本文报导了在正交偏光镜下，对人体胆汁液晶的光学性质的研究，结果表明，胆汁液晶是一种非均质体，在正交偏光镜下，呈现出特殊的干涉图样和四次消光现象，光性符号是单轴正性的，干涉色级是一级灰白，双折射率Δｎ＝０．０１１－０．０１７。     

Nanomaterials‐Based Surface Protein Imprinted Polymers: Synthesis and Medical Applications

Proteins are an essential part of organisms and play a very important role in life activities. Molecular imprinting technology (MIT) can prepare functional materials with specific identification abilities. In recent years, various molecularly imprinted materials have been widely used in the fields of solid‐phase extraction, bionic sensing, and on‐line analysis. Due to the limit of the properties of protein macromolecules, the development of MIT for protein molecules is relatively slow. With the continuous deepening on the research of nanomaterials and surface molecular imprinting technology, a large numbers of interesting and successful strategies appear on imprinted protein. Some surface protein imprinting materials with excellent properties and unique functions are applied in proteomics, biological imaging, medical diagnosis, and other fields, showing great potential application value. This paper summarizes the latest preparation and analysis strategies of surface protein imprinting based on nanomaterials, introduces medical application of protein imprinting materials in sample separation and purification, proteomics, biomedical and other aspects in recent years, and looks forward to the development opportunities and challenges in protein imprinting field.     

基于微流控平台的胶质母细胞瘤干细胞中miRNA-874表达的研究

目的通过微流控检测平台,研究miRNA-874（miR-874）表达在胶质母细胞瘤干细胞（GSCs）生长中的作用及意义。 方法应用高通量、多样本、低成本的微流控技术,对GSCs和神经干细胞（NSCs）进行miR-874转染,并通过荧光定量PCR检测细胞内miR-874和mRNA表达等一系列细胞分子生物实验,研究miRNA-874对GSCs生长和凋亡的作用。 结果miR-874在GSCs中的表达显著降低,约为NSCs中表达量的2%~40%（P<0.05）。利用树状分子将miR-874转染入GSCs中后,GSCs的细胞数量显著下降,凋亡细胞的数量显著上升,提示miR-874对GSCs具有杀伤作用。 结论miR-874在GSCs中表达显著降低,在GSCs中过表达miR-874会导致显著的细胞生长抑制和死亡,有助于开发基于miRNA的新型脑癌药物和疗法。     

聚嘧啶束结合蛋白相关剪接因子高表达对糖基化终末产物诱导下视网膜色素上皮细胞损伤的保护作用

目的观察聚嘧啶束结合蛋白相关剪接因子(PSF)高表达对糖基化终末产物(AGEs)诱导下RPE细胞损伤的保护作用。方法将体外培养的人RPE细胞分为正常对照组(N组)、空白对照组(N+AGAGEs组)、空载体对照组(Vec+AGEs组)、PSF高表达组(PSF+AGEs组)。N组RPE细胞常规培养;N+AGEs组只做转染处理但不导入任何外源性基因的RPE细胞联合AGEs诱导;Vec+AGEs组、PSF+AGEs组利用转染试剂脂质体2000将pcDNA空载体或pcDNA-PSF真核表达质粒导入RPE细胞联合AGEs诱导。除N组以外,其余3组细胞进行相应的转染处理,24 h后应用150μg/ml的AGEs刺激72 h。采用HE染色和Hoechst 33258染色观察PSF高表达对RPE细胞凋亡相关形态改变的影响;通过ROS水平检测分析PSF高表达对AGEs诱导的RPE细胞ROS表达的影响;采用MTT比色法检测PSF高表达对RPE细胞生存力的影响;采用Western blot检测PSF不同作用时间及不同剂量对血红素氧合酶1(HO-1)表达的影响。结果HE染色和Hoechst 33258染色观察发现,N组细胞形态饱满,细胞核呈圆形,细胞质丰富,染色均一;N+AGEs组、Vec+AGEs组细胞体积缩小,嗜酸性染色增强,细胞核致密浓染、固缩甚至碎裂;PSF+AGEs组细胞形态尚饱满,细胞浆染色较均匀,细胞核染色均一。MTT比色法检测结果显示,PSF高表达可有效提高RPE细胞生存力,但该作用可被ZnPP有效拮抗,且差异有统计学意义(F=33.26,P<0.05)。DCFH-DA法检测结果显示,与N+AGEs组、Vec+AGEs组比较,PSF+AGEs组细胞中ROS产量下降,差异有统计学意义(F=11.94,P<0.05)。Western blot检测结果显示,PSF蛋白以时间、剂量依赖性的方式上调HO-1的表达水平。PSF蛋白作用24、48、72 h的HO-1相对表达水平较0 h明显升高,差异有统计学意义(F=164.91,P<0.05)。0.1、0.5、1.0、1.5、2.0μg PSF蛋白作用下的HO-1相对表达水平较0.0μg明显升高,差异有统计学意义(F=104.82,P<0.05)。结论PSF可能通过上调HO-1的表达而抑制ROS产生,从而对AGEs诱导下的RPE细胞损伤发挥保护作用。     

Primary spinal intradural extraskeletal Ewing sarcoma mimicking a giant nerve sheath tumor: case report and review of the literature

Primary intradural extraskeletal Ewing sarcoma is a very rare form of malignant neoplasm. Only few cases have been reported on the literature. Here, we report a case of a 14-year-old boy who had a chief complaint of pain and tingling in the right lower limb. The patient initially seemed to have a giant nerve sheath tumor but was eventually diagnosed with intradural extraskeletal Ewing sarcoma arising from the nerve roots of the cauda equine. The literature with regard to primary spinal intradural extraskeletal Ewing sarcoma is reviewed.     

The Biomedical Research Hub: a federated platform for patient research data

ObjectiveThe objective was to develop and operate a cloud-based federated system for managing, analyzing, and sharing patient data for research purposes, while allowing each resource sharing patient data to operate their component based upon their own governance rules. The federated system is called the Biomedical Research Hub (BRH).Materials and MethodsThe BRH is a cloud-based federated system built over a core set of software services called framework services. BRH framework services include authentication and authorization, services for generating and assessing findable, accessible, interoperable, and reusable (FAIR) data, and services for importing and exporting bulk clinical data. The BRH includes data resources providing data operated by different entities and workspaces that can access and analyze data from one or more of the data resources in the BRH.ResultsThe BRH contains multiple data commons that in aggregate provide access to over 6 PB of research data from over 400 000 research participants.Discussion and conclusionWith the growing acceptance of using public cloud computing platforms for biomedical research, and the growing use of opaque persistent digital identifiers for datasets, data objects, and other entities, there is now a foundation for systems that federate data from multiple independently operated data resources that expose FAIR application programming interfaces, each using a separate data model. Applications can be built that access data from one or more of the data resources.     

Robotic ureteroplasty with appendiceal onlay flap: an update on the outcomes of 18-month follow-up

BackgroundTo describe our technical experience of robotic appendiceal onlay flap ureteroplasty (RAUP) for complex ureteral stricture disease and report the updated analysis of 18-month follow-up outcomes.MethodsSince May 2019, nine patients with right ureteral strictures have undergone RAUP in our medical centre. Patients’ perioperative data and follow-up information were collected prospectively. Patients were excluded in present study if the postoperative follow-up time was less than 6 months.ResultsEight patients were recruited. Proximal ureteric strictures were present in 5 patients, and 3 patients had middle ureteric strictures. The mean stricture length was 4.3 cm (range, 3.0–6.0 cm). Nephrostomy was performed in 4 patients, and 4 patients had indwelling double-J ureteral stents before they were admitted to our hospital. All operations were implemented successfully without intraoperative complications. The mean operation time was 162 minutes (range, 135–211 minutes), and the mean estimated blood loss was 78 mL (range, 30–200 mL). The mean postoperative hospital stay was 8 days (range, 4–12 days). No patients had high-grade postoperative complications (Clavien-Dindo III and IV) 30 days after surgery. At a mean follow-up of 18 months (range, 6–28 months), all patients were not needed further surgical intervention and could be considered successful. But 2 cases still have stable mild hydronephrosis without symptoms such as flank pain or fever.ConclusionsRAUP is a workable option for managing long-segment (3–6 cm) proximal and middle ureteral strictures of the right side. The outcomes of 18-month follow-up are satisfactory.     

组织培养对乳胰B细胞功能和形态的影响

本文报道了不同培养时间对乳胰组织培养后胰岛活性的影响。通过对各组培养液胰岛素含量的测定和使用免疫组化与显微图象分析技术对 B 细胞内胰岛素的定性和定量观察表明,新鲜乳胰碎片行短期组织培养(2～8天),可获得良好的效果。