Resource and hardware options for microarray-based experimentation.

DNA microarray technology permits the study of biological systems and processes on a genome-wide scale. Arrays based on cDNA clones, oligonucleotides and genomic clones have been developed for investigations of gene expression, genetic analysis and genomic changes associated with disease. Over the past 3-4 years, microarrays have become more widely available to the research community. This has occurred through increased commercial availability of custom and generic arrays and the development of robotic equipment that has enabled array printing and analysis facilities to be established in academic research institutions. This brief review examines the public and commercial resources, the microarray fabrication and data capture and analysis equipment currently available to the user.     

Localisation of plum pox virus in apricot stem and petiole tissues by tissue printing onto nitrocellulose membrane

The localisation of plum pox virus (PPV) in stem and petiole tissues of nine susceptible apricot cultivars and GF305 peach seedling has been studied. From stem and petioles consecutive transverse sections spaced at 1 mm were made and tissue sections printed onto nitrocellulose membrane. The resulting prints were probed with a specific antibody for plum pox virus, followed by a rabbit anti-goat antibody conjugated with horse radish peroxidase, in order to localise the virus within the tissues. In stems the virus was mainly present in xylem and pith. The possible presence of the virus in the sclerenchyma is discussed. In petioles the virus was present in epidermis and parenchymas, but not in vessels. The probable movement through the xylem and from cell to cell has been shown.     

In vitro biocompatibility evaluation of a heat‐resistant 3D printing material for use in customized cell culture devices

Additive manufacturing (3D printing) enables the fabrication of highly customized and complex devices and is therefore increasingly used in the field of life sciences and biotechnology. However, the application of 3D‐printed parts in these fields requires not only their biocompatibility but also their sterility. The most common method for sterilizing 3D‐printed parts is heat steam sterilization—but most commercially available 3D printing materials cannot withstand high temperatures. In this study, a novel heat‐resistant polyacrylate material for high‐resolution 3D Multijet printing was evaluated for the first time for its resistance to heat steam sterilization and in vitro biocompatibility with mouse fibroblasts (L929), human embryonic kidney cells (HEK 293E), and yeast (Saccharomyces cerevisiae (S. cerevisiae)). Analysis of the growth and viability of L929 cells and the growth of S. cerevisiae confirmed that the extraction media obtained from 3D‐printed parts had no negative effect on the aforementioned cell types, while, in contrast, viability and growth of HEK 293E cells were affected. No different effects of the material on the cells were found when comparing heat steam sterilization and disinfection with ethanol (70%, v/v). In principle, the investigated material shows great potential for high‐resolution 3D printing of novel cell culture systems that are highly complex in design, customized and easily sterilizable—however, the biocompatibility of the material for other cell types needs to be re‐evaluated.     

3D‐Printed Cathodes of LiMn1−xFexPO4 Nanocrystals Achieve Both Ultrahigh Rate and High Capacity for Advanced Lithium‐Ion Battery

A 3D‐printing technology and printed 3D lithium‐ion batteries (3D‐printed LIBs) based on LiMn_0.21Fe_0.79PO₄@C (LMFP) nanocrystal cathodes are developed to achieve both ultrahigh rate and high capacity. Coin cells with 3D‐printed cathodes show impressive electrochemical performance: a capacity of 108.45 mAh g^?1 at 100 C and a reversible capacity of 150.21 mAh g^?1 at 10 C after 1000 cycles. In combination with simulation using a pseudo 2D hidden Markov model and experimental data of 3D‐printed and traditional electrodes, for the first time deep insight into how to achieve the ultrahigh rate performance for a cathode with LMFP nanocrystals is obtained. It is estimated that the Li‐ion diffusion in LMFP nanocrystal is not the rate‐limitation step for the rate to 100 C, however, that the electrolyte diffusion factors, such as solution intrinsic diffusion coefficient, efficiency porosity, and electrode thickness, will dominate ultrahigh rate performance of the cathode. Furthermore, the calculations indicate that the above factors play important roles in the equivalent diffusion coefficient with the electrode beyond a certain thickness, which determines the whole kinetic process in LIBs. This fundamental study should provide helpful guidance for future design of LIBs with superior electrochemical performance.     

3D生物打印在软骨修复中的应用*

关节软骨损伤后的自我修复是医学界一直在研究和探讨的难题。3D生物打印技术可以精准的分配载细胞生物材料,构建复杂的三维活体组织,在优化软骨缺损修复组织的内部结构、机械性能以及生物相容性上有很大优势,因此近年来成为软骨修复组织工程领域的研究热点。重点介绍了软骨生物3D生物打印的最新进展,包括软骨生物打印“墨水”材料的选择、种子细胞的来源以及3D生物打印技术的发展。此外,还阐述了3D生物打印技术在组织工程学应用上的部分局限性,并对其在软骨修复领域的发展与应用进行了预测。     

Prolongation of Life in Anephric Rats following de novo Renal Organogenesis

One solution to the shortage of human organs available for transplantation envisions growing new organs in situ. This can be accomplished by transplantation of developing organ anlagen/primordia. Allotransplantation of embryonic day 15 metanephroi into the omentum of adult hosts is followed by differentiation, growth, vascularization and function of the implants. Here we show that survival of rats with all native renal mass removed can be increased by prior metanephros transplantation and ureteroureterostomy. Excretion of urine formed by metanephroi is prerequisite for enhanced survival. This is the first demonstration that life can be extended following de novo renal organogenesis.     

An active learning approach to investigate the ecosystem of tide flats using 3D modeling and printing

ABSTRACT

This paper presents an active learning approach that focuses on practical investigation of the ecosystem of tidal flats using 3D modeling and printing for biology students in order to enhance understanding of natural selection. The learning approach for the study followed a 5-step procedure: i) learning about 3D modeling and printing, ii) exploration of the ecosystem of tidal flats, iii) 3D designing of a bird beak, iv) 3D printing of a constructed beak, and v) a natural selection simulation activity. The learning method presented in this study centered on active student exploration of the tidal flats ecosystem using 3D modeling and printing. The learning approach presented in this paper could be implicated at schools to aid in students’ understanding of natural selection as it allows students to firsthand examine simulation changes to a bird beak and benthic communities. This study suggested the active learning method for natural selection as it incorporates student-designed exploration and direct investigative appraisal of the selection process.     

Estimation of Jordanian isolated Pectobacterium cellulase,pectinase concentrations,RAPD polymorphism and their maceration activity

Forty-two Pectobacterium isolates were recovered from contaminated soil and rotted vegetables in Jordan. Twenty of them were belonged to; Pectobacterium carotovorum subsp. Carotovorum (Pbc) (= Erwinia carotovora subsp. carotovora), 11 isolates were belonged to Pectobacterium atrospeticum (= Erwinia carotovora subsp. atroseptica) (Pba) and 11 isolates were not classifiable (Pbs). Maceration activity of the 42 proved their ability to macerate potato, carrot and radish slices. Maceration activity of the isolates either of the same subspecies or in between the isolates of different subspecies isolated from the same host or from different hosts was varied. The measured concentration in μM?ml^?1 of both cellulase and pectinase enzymes was variable too. The Rapid amplified polymorphic DNA-PCR finger printing of total genomic DNA using a pair of 10-mer oligonucleotide primers amplification showed similar DNA bands with some polymorphic variations amongst the isolates.