연구는 Artères 재단, 스텔라 재단 유럽과 Boninchi 재단에 의해 지원되었다. CT는 스위스 국립 과학 재단 (점수 부여 3232230-126233)에 의해 지원되었다.

1. 손잡이 : 설계 및 형성 <ol><li> 테이프와 나무 보드에 NR 10 탄소 메스 블레이드를 고정합니다. </li><li> 현미경으로 고리의 중심에 태그를. 그것은 메스 블레이드의 숲에서 바로 1.2 cm에 위치해야합니다. </li><li> 구형 다이아몬드 비트 2 mm 구멍을 드릴, 고속 드릴에 장착. </li><li> 방추형 또는 원추형 다이아몬드 비트 구멍을 넓 힙니다. 표 1에서와 같이 최종 직경은 쥐의 무게에 따라 다릅니다. </li><li> 영구 마커 핸들의 모양을 디자인합니다. 그림 1과 2는 스텐실로 사용할 수 있습니다. </li><li> 미니 벤치 그라인더에 드릴을 변환 형태 외부 칼날의 부분을 제거합니다. </li><li> 브러시를 회전 낮은 속도로 조각을 반올림. </li></ol> 2. Approximator : 설계 및 형성 <ol><li> approximator은 수정 바로 수술 클레머의 또는 KOCHER의 forcep하여 얻을 수 있습니다의. </li><li> 고속 미니 벤치 분쇄기를 사용하여 현미경으로 한 지점의 절반을 잘라. </li><li> 완전하게 밀어 핸들 수 있도록 양쪽에 대칭 홈을 만든다. </li><li> 긴 팔 길이 방향 슬릿을 잘라 긴 팔의 중심과 잘 배치 처리는 같은 축에 있는지 확인합니다. </li><li> 핸들의 중심을 향하게 긴 팔에 노치를 디자인합니다. </li><li> 브러시를 회전 낮은 속도로 조각 오프 최대한 얇고 둥근 분기를합니다. </li></ol> 3. 팔목 : 설계 및 형성 <ol><li> 커프스 캘리퍼스 쥐의 체중과 변형에 따라 다릅니다. 대조적으로, 그 길이는 4mm 정도로 유지해야한다. </li><li> NR 10 메스 한쪽 가장자리 떨어져 미세 구멍 폴리에틸렌 튜빙 라운드를 가져 가라. </li><li> 가장자리에서 숲 0.5 mm를 설계,주의 깊게 숲에 추락 경사를 잘라. </li><li> 튜브에 하나 또는 두 개의 전층 흠을 잘라. 이러한 것이식 준비 및 이식 동안 커프를 조작하는 데 도움이됩니다. </li><li> 의 가장자리에서 4mm에 커프를 잘라. </li></ol>

<ol>
	<li>Oldani, G., Lacotte, S., Morel, P., Mentha, G., Toso, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Orthotopic+Liver+Transplantation+in+Rats.">Orthotopic Liver Transplantation in Rats.</a> J. Vis. Exp. (65), e4143 (2012).</li><li>Hori, T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comprehensive+and+innovative+techniques+for+liver+transplantation+in+rats:+A+surgical+guide.">Comprehensive and innovative techniques for liver transplantation in rats: A surgical guide.</a> World Journal of Gastroenterology., WJG. 16, 3120 (2010).</li><li>Kashfi, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+review+of+various+techniques+of+orthotopic+liver+transplantation+in+the+rat.">A review of various techniques of orthotopic liver transplantation in the rat.</a> Transplantation Proceedings. 37 (1), 185-188 (2005).</li><li>Kamada, N., Calne, R. Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Orthotopic+liver+transplantation+in+the+rat.+Technique+using+cuff+for+portal+vein+anastomosis+and+biliary+drainage.">Orthotopic liver transplantation in the rat. Technique using cuff for portal vein anastomosis and biliary drainage.</a> Transplantation. 28, 47 (1979).</li><li>Oldani, G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+novel+technique+for+rat+liver+transplantation+using+Quick+Linker+system:+a+preliminary+result.">A novel technique for rat liver transplantation using Quick Linker system: a preliminary result.</a> Journal of Surgical Research. 149, 303-309 (2008).</li></ol>

저자는 공개 아무것도 없어.

본 보고서는 쉽게 쥐의 간 이식을위한 빠른 링커 시스템의 설계 및 건축에 대해 설명합니다. 쥐의 간 이식은 1990 년대 초반 (이후 매년 발간 125-180 관련 서류와 함께 인기있는 모델입니다 <a href="http://www.pubmed.com" target="_blank">www.pubmed.com</a> ). 그것은 면역과 이식 보존 문제를 탐사 등 실험의 광범위한 수 있습니다. &quot;빠른 링커&quot;키트의 사용은 보장 내막 - 투 - 내막의 접촉 쉽고 빠르게 문합 수 있습니다. 쥐의 간 이식의 기술적 단계에 대한 자세한 설명과 논의는 이전에 1 설명하고있다. 빠른 링커 키트는 일반적인 실험실 자료에서 저렴한 가격에 구축 할 수 있습니다. 발생하는 주요 과제는 칫솔질 최종시 한 핸들 고장 관련이 있으며,이 문제는 좁은 파를 설정하여 해결 된0.5 mm (그림 1과 2는 적절한 크기를 보여줍니다)에서 핸들 링의 t. 블레이드의 품질에 관해서는, 스테인레스 스틸이 고려되어야한다. 평균 탄소 강철 잎에 약간 덜 유연 비교하지만, 스테인레스 스틸 칼날이 손잡이의 일생의 사용을 허용, 녹을 개발하지 않습니다. 참고로, 현재 핸들과 소맷 부리의 디자인은 가장 효율적인 문합을 허용, 제안 된 크기를 주도 프로세스의 결과입니다. 커프 직경은 쥐의 무게 (표 1)에 따라 다릅니다. 최소한의 변화는 약 4 mm (그림 3과 4)의 일반적인 길이 길이의 측면에서 허용 될 수 있습니다. approximator에 대하여, 선택한 KOCHER의 forcep이 지점에서 최소 4 센티미터 처리해야합니다. 이 동물의 복부 외부 랙의 안전 폐쇄 할 수 있습니다. 전반적으로,제안 된 장치는 간 쥐에 이식의 다른 유형의 이식 쉽게 정맥 ​​문합을 허용 할 수 있습니다.

동소 쥐의 간 이식의 기술이 구상 실험 종이 1의 최근 연구에 표시되었습니다. 포털 정맥과 인프라 간 대정맥 문합은 빠른 링커 보조 커프 기법을 사용하여 수행 하였다. 이 기술은 쉽게 빠르게 문합, 더 나은 혈역학 적 결과에 대해 허용하는, 원래의 Kamada의 기술 2-4의 다른 버전 사이에서 선택되었고, 짧은 학습 곡선 1.5으로 구현 될 수있다. 빠른 링커 기술은 핸들의 사용을 필요 approximator와 소맷 부리에이 모든 것이가 본 보고서에서 설명하는 기술에 따라 일반적인 실험실 재료로 설계 할 수 있습니다.

<table border="1">
<tbody>
 <tr>
 <td>Tool / Reagent</td>
 <td>Company</td>
 <td>Catalogue n.</td>
 <td>Comment</td>
 </tr>
 <tr>
 <td>Porta cuff</td>
 <td>altecweb or 
 smiths-medical</td>
 <td>Coil 01-96-1729 
 800/100/420</td>
 <td>Bore : variable 
 Wall : 0.30 mm 
 Length: 3.8-4.2 mm 
 <a href="http://altecweb.com" target="_blank">altecweb.com</a> or 
 <a href="http://smiths-medical.com" target="_blank">smiths-medical.com</a></td>
 </tr>
 <tr>
 <td>IVC cuff</td>
 <td>altecweb or 
 smiths-medical </td>
 <td>Coil 01-96-1733 
 800/100/540</td>
 <td>Bore : variable 
 Wall : 0.30 mm 
 Length: 3.8-4.2 mm 
 <a href="http://altecweb.com" target="_blank">altecweb.com</a> or 
 <a href="http://smiths-medical.com" target="_blank">smiths-medical.com</a></td>
 </tr>
 <tr>
 <td>Mini-drill </td>
 <td>Dremel</td>
 <td>100 series</td>
 <td>35,000 rpm 
 <a href="http://dremel.com" target="_blank">dremel.com</a></td>
 </tr>
 <tr>
 <td>Diamond wheel point</td>
 <td>Dremel</td>
 <td>7103</td>
 <td>2 mm 
 <a href="http://dremel.com" target="_blank">dremel.com</a></td>
 </tr>
 <tr>
 <td>Diamond wheel point</td>
 <td>Dremel</td>
 <td>7105</td>
 <td>4.4 mm 
 <a href="http://dremel.com" target="_blank">dremel.com</a></td>
 </tr>
 <tr>
 <td>Diamond wheel point</td>
 <td>Dremel</td>
 <td>7144</td>
 <td>2.4 mm 
 <a href="http://dremel.com" target="_blank">dremel.com</a></td>
 </tr>
 <tr>
 <td>Cut-off wheels</td>
 <td>Dremel</td>
 <td>420</td>
 <td>dia: 23.8 mm 
 thickness: 0.5 mm 
 <a href="http://dremel.com" target="_blank">dremel.com</a></td>
 </tr>
 <tr>
 <td>Quick-linker handles</td>
 <td>dltchiropody (DLT)</td>
 <td>PAR 10</td>
 <td>modified scalpel blades 
 <a href="http://dltchiropody.co.uk" target="_blank">dltchriopdy</a></td>
 </tr>
 <tr>
 <td>Quick-linker approximator</td>
 <td>pharmap</td>
 <td>UD-04-275</td>
 <td>modified Kocher's forceps 
 <a href="http://pharmap.ch" target="_blank">pharmap.ch</a></td>
 </tr>
 </tbody>
</table>

manufacturing devices and instruments for easier rat liver transplantation

동소 쥐의 간 이식 &quot;빠른 링커&quot;장치의 사용과 최근 조브 용지에 표시 한 인기 모델입니다. 이 기술은 커프스 anatomoses 합리적인 학습 곡선 후 쉽게 정맥 ​​수 있습니다. 이 장치는 메스 블레이드에 새겨진 두 개의 손잡이, 한 KOCHER의 집게를 수정하여 얻을 수 approximator, 그리고 미세 구멍 폴리에틸렌 튜브의 설계 수갑으로 구성되어 있습니다. 전체 프로세스는 낮은 비용으로 사용하는 일반적인 소재 실험실에서 수행 할 수 있습니다. 본 보고서는 필요한 조각의 설계를위한 단계별 프로토콜을 제공하고 스텐실이 포함되어 있습니다.

다섯 approximators 11 핸들 등 5 개 키트, 제조하고 있습니다. 하나의 손잡이는 솔질 최종 동안 끊었다. 이 문제는 핸들의 고리가 너무 급하여 때문이고, 그것은 0.5 mm에서 핸들 링의 좁은 부분을 설정하여 해결되었습니다. 아무런 문제 approximators의 형성 동안 발생하지 않습니다. <table border="1"><tbody><tr><td> 쥐의 무게 (g) </td><td> 포르타 핸들 (안 dia) (mm) </td><td> 포르타 팔목 (외부 직경) (mm) </td><td> IVC 핸들 (안 dia) (mm) </td><td> IVC 커프 (외부 직경) (mm) </td></tr><tr><td> 120-180 </td><td> 2.2 </td><td> 1.7 </td><td> 2.6 </td><td> 2.08 </td></tr><tr><td> 180-270 </td><td> 2.6 </td><td> 2.08 </td><td> 3.4-3.7 </td><td> 3.0-3.25 </td></tr><tr><td> &gt; 270 </td><td> 2.9<html></td><td> 2.42 </td><td> 4.2 </td><td> 3.7 </td></tr></tbody></table> 표 1. <img src="/files/ftp_upload/50380/50380fig1.jpg" alt="그림 1" fo:content-width="6in" fo:src="/files/ftp_upload/50380/50380fig1highres.jpg"/> 그림 1. 1시 1분가 형성 핸들을 안내하는 데 사용할 수있는 스케일로 인쇄합니다. 포르타 핸들 스텐실. <a href="https://www.jove.com/files/ftp_upload/50380/50380fig1large.jpg" target="_blank">큰 그림을 보려면 여기를 클릭하십시오</a> . <img src="/files/ftp_upload/50380/50380fig2.jpg" alt="그림 2" fo:content-width="6in" fo:src="/files/ftp_upload/50380/50380fig2highres.jpg"/> 그림 2. 1시 1분가 형성 핸들을 안내하는 데 사용할 수있는 스케일로 인쇄합니다. IVC 핸들 스텐실. <a href="https://www.jove.com/files/ftp_upload/50380/50380fig2large.jpg" target="_blank">큰 그림을 보려면 여기를 클릭하십시오</a> . 내용 &quot;&gt; <img src="/files/ftp_upload/50380/50380fig3.jpg" alt="그림 3" fo:content-width="4.6in" fo:src="/files/ftp_upload/50380/50380fig3highres.jpg" /> 그림 3. 포르타 및 IVC 팔목 측면보기. 이식의 v.porta는 측면 하나에받는 사람의 용기있는 동안, 중앙 홈에 고정되어야한다. 이 편법은 최적의 내막 - 투 - 내막 접촉 할 수 있습니다. <img src="/files/ftp_upload/50380/50380fig4.jpg" alt="그림 4" fo:content-width="4.1in" fo:src="/files/ftp_upload/50380/50380fig4highres.jpg"/> 그림 4. 180-270그램 무게 쥐에 적합 포르타 및 IVC 친다 전면보기입니다. 캘리퍼스가 표시됩니다.

Watch this Scientific Journal Video about Manufacturing Devices and Instruments for Easier Rat Liver Transplantation at JoVE.com

Manufacturing Devices and Instruments for Easier Rat Liver Transplantation

우리는 쉽게 동소 쥐의 간 이식에 대한 &quot;빠른 링커&quot;장치의 디자인을 설명합니다.

쉬운 쥐 간 이식을위한 제조 장치 및 기기

Orthotopic rat liver transplantation is a popular model, which has been shown in a recent JoVE paper with the use of the "quick-linker" device. This ...

manufacturing-devices-instruments-for-easier-rat-liver

Research

JoVE Journal

Bioengineering

8.6K 조회수.  University of Geneva Hospitals. 우리는 쉽게 동소 쥐의 간 이식에 대한 "빠른 링커"장치의 디자인을 설명합니다.

비디오: Manufacturing Devices and Instruments for Easier Rat Liver Transplantation

Mass Cytometry: Protocol for Daily Tuning and Running Cell Samples on a CyTOF Mass Cytometer

In recent years, the rapid analysis of single cells has commonly been performed using flow cytometry and fluorescently-labeled antibodies. However, the issue of spectral overlap of fluorophore emissions has limited the number of simultaneous probes. In contrast, the new CyTOF mass cytometer by DVS Sciences couples a liquid single-cell introduction system to an ICP-MS.1 Rather than fluorophores, chelating polymers containing highly-enriched metal isotopes are coupled to antibodies or other specific probes.2-5 Because of the metal purity and mass resolution of the mass cytometer, there is no "spectral overlap" from neighboring isotopes, and therefore no need for compensation matrices. Additionally, due to the use of lanthanide metals, there is no biological background and therefore no equivalent of autofluorescence. With a mass window spanning atomic mass 103-203, theoretically up to 100 labels could be distinguished simultaneously. Currently, more than 35 channels are available using the chelating reagents available from DVS Sciences, allowing unprecedented dissection of the immunological profile of samples.6-7
Disadvantages to mass cytometry include the strict requirement for a separate metal isotope per probe (no equivalent of forward or side scatter), and the fact that it is a destructive technique (no possibility of sorting recovery). The current configuration of the mass cytometer also has a cell transmission rate of only ~25%, thus requiring a higher input number of cells.
Optimal daily performance of the mass cytometer requires several steps. The basic goal of the optimization is to maximize the measured signal intensity of the desired metal isotopes (M) while minimizing the formation of oxides (M+16) that will decrease the M signal intensity and interfere with any desired signal at M+16. The first step is to warm up the machine so a hot, stable ICP plasma has been established. Second, the settings for current and make-up gas flow rate must be optimized on a daily basis. During sample collection, the maximum cell event rate is limited by detector efficiency and processing speed to 1000 cells/sec. However, depending on the sample quality, a slower cell event rate (300-500 cells/sec) is usually desirable to allow better resolution between cells events and thus maximize intact singlets over doublets and debris. Finally, adequate cleaning of the machine at the end of the day helps minimize background signal due to free metal.

The steps necessary for daily tuning and optimization of the performance of a CyTOF mass cytometer are described. Comments on optimal sample preparation and flow rate are discussed

대량 세포 계측법 : CyTOF 질량 Cytometer에 매일 조정하고 실행 세포 샘플에 대한 프로토콜

In recent years, the rapid analysis of single cells has commonly been performed using flow cytometry and fluorescently-labeled antibodies. However, the ...

연구

생체공학

Paper-based Devices for Isolation and Characterization of Extracellular Vesicles

Extracellular vesicles (EVs), membranous particles released from various types of cells, hold a great potential for clinical applications. They contain nucleic acid and protein cargo and are increasingly recognized as a means of intercellular communication utilized by both eukaryote and prokaryote cells. However, due to their small size, current protocols for isolation of EVs are often time consuming, cumbersome, and require large sample volumes and expensive equipment, such as an ultracentrifuge. To address these limitations, we developed a paper-based immunoaffinity platform for separating subgroups of EVs that is easy, efficient, and requires sample volumes as low as 10 &#956;l. Biological samples can be pipetted directly onto paper test zones that have been chemically modified with capture molecules that have high affinity to specific EV surface markers. We validate the assay by using scanning electron microscopy (SEM), paper-based enzyme-linked immunosorbent assays (P-ELISA), and transcriptome analysis. These paper-based devices will enable the study of EVs in the clinic and the research setting to help advance our understanding of EV functions in health and disease.

This protocol details a method to isolate extracellular vesicles (EVs), small membranous particles released from cells, from as little as 10 &#956;l serum samples. This approach circumvents the need for ultracentrifugation, requires only a few minutes of assay time, and enables the isolation of EVs from samples of limited volumes.

세포 외 소포의 분리 및 특성에 대한 종이 기반의 장치

Extracellular vesicles (EVs), membranous particles released from various types of cells, hold a great potential for clinical applications. They contain ...

Procedure for Decellularization of Rat Livers in an Oscillating-pressure Perfusion Device

Decellularization and recellularization of parenchymal organs may enable the generation of functional organs in vitro, and several protocols for rodent liver decellularization have already been published. We aimed to improve the decellularization process by construction of a proprietary perfusion device enabling selective perfusion via the portal vein and/or the hepatic artery. Furthermore, we sought to perform perfusion under oscillating surrounding pressure conditions to improve the homogeneity of decellularization. The homogeneity of perfusion decellularization has been an underestimated factor to date. During decellularization, areas within the organ that are poorly perfused may still contain cells, whereas the extracellular matrix (ECM) in well-perfused areas may already be affected by alkaline detergents. Oscillating pressure changes can mimic the intraabdominal pressure changes that occur during respiration to optimize microperfusion inside the liver. In the study presented here, decellularized rat liver matrices were analyzed by histological staining, DNA content analysis and corrosion casting. Perfusion via the hepatic artery showed more homogenous results than portal venous perfusion did. The application of oscillating pressure conditions improved the effectiveness of perfusion decellularization. Livers perfused via the hepatic artery and under oscillating pressure conditions showed the best results. The presented techniques for liver harvesting, cannulation and perfusion using our proprietary device enable sophisticated perfusion set-ups to improve decellularization and recellularization experiments in rat livers.

The presented techniques for liver harvesting, cannulation and perfusion using our proprietary device enable sophisticated perfusion set-ups to improve decellularization and recellularization experiments in rat livers.

진동 압 관류 장치에서 쥐 간을의 탈세 포화 절차

Decellularization and recellularization of parenchymal organs may enable the generation of functional organs in vitro, and several protocols for rodent ...

Fabricating Cotton Analytical Devices

A robust, low-cost analytical device should be user-friendly, rapid, and affordable. Such devices should also be able to operate with scarce samples and provide information for follow-up treatment. Here, we demonstrate the development of a cotton-based urinalysis (i.e., nitrite, total protein, and urobilinogen assays) analytical device that employs a lateral flow-based format, and is inexpensive, easily fabricated, rapid, and can be used to conduct multiple tests without cross-contamination worries. Cotton is composed of cellulose fibers with natural absorptive properties that can be leveraged for flow-based analysis. The simple but elegant fabrication process of our cotton-based analytical device is described in this study. The arrangement of the cotton structure and test pad takes advantage of the hydrophobicity and absorptive strength of each material. Because of these physical characteristics, colorimetric results can persistently adhere to the test pad. This device enables physicians to receive clinical information in a timely manner and shows great potential as a tool for early intervention.

To investigate simple fabrication approaches for multiple assay needs, we created a fluid-absorbing channel system made of cotton material. This device was used to establish a multiple detection platform, and solve contamination issues that commonly affect lateral flow-based biomedical devices, for clinical urinalysis of nitrite, total protein, and urobilinogen.

면 분석 장치를 제조

A robust, low-cost analytical device should be user-friendly, rapid, and affordable. Such devices should also be able to operate with scarce samples and ...

Optimized Setup and Protocol for Magnetic Domain Imaging with In Situ Hysteresis Measurement

This paper elaborates the sample preparation protocols required to obtain optimal domain patterns using the Bitter method, focusing on the extra steps compared to standard metallographic sample preparation procedures. The paper proposes a novel bespoke rig for dynamic domain imaging with in situ BH (magnetic hysteresis) measurements and elaborates the protocols for the sensor preparation and the use of the rig to ensure accurate BH measurement. The protocols for static and ordinary dynamic domain imaging (without in situ BH measurements) are also presented. The reported method takes advantage of the convenience and high sensitivity of the traditional Bitter method and enables in situ BH measurement without interrupting or interfering with the domain wall movement processes. This facilitates establishing a direct and quantitative link between the domain wall movement processes&#8211;microstructural feature interactions in ferritic steels with their BH loops. This method is anticipated to become a useful tool for the fundamental study of microstructure&#8211;magnetic property relationships in steels and to help interpret the electromagnetic sensor signals for non-destructive evaluation of steel microstructures.

Optimized Setup and Protocol for Magnetic Domain Imaging with In Situ Hysteresis Measurement

This paper elaborates the sample and sensor preparation procedures and the protocols for using the test rig particularly for dynamic domain imaging with in situ BH measurements in order to achieve optimal domain pattern quality and accurate BH measurements.

최적화 된 설치 및 히스테리시스 측정 현장에서 자기 도메인 이미징에 대 한 프로토콜

This paper elaborates the sample preparation protocols required to obtain optimal domain patterns using the Bitter method, focusing on the extra steps ...

A Novel Surgical Technique As a Foundation for In Vivo Partial Liver Engineering in Rat

Organ engineering is a novel strategy to generate liver organ substitutes that can potentially be used in transplantation. Recently, in vivo liver engineering, including in vivo organ decellularization followed by repopulation, has emerged as a promising approach over ex vivo liver engineering. However, postoperative survival was not achieved. The aim of this study is to develop a novel surgical technique of in vivo selective liver lobe perfusion in rats as a prerequisite for in vivo liver engineering. We generate a circuit bypass only through the left lateral lobe. Then, the left lateral lobe is perfused with heparinized saline. The experiment is performed with 4 groups (n = 3 rats per group) based on different perfusion times of 20 min, 2 h, 3 h, and 4 h. Survival, as well as the macroscopically visible change of color and the histologically determined absence of blood cells in the portal triad and the sinusoids, is taken as an indicator for a successful model establishment. After selective perfusion of the left lateral lobe, we observe that the left lateral lobe, indeed, turned from red to faint yellow. In a histological assessment, no blood cells are visible in the branch of the portal vein, the central vein, and the sinusoids. The left lateral lobe turns red after reopening the blocked vessels. 12/12 rats survived the procedure for more than one week. We are the first to report a surgical model for in vivo single liver lobe perfusion with a long survival period of more than one week. In contrast to the previously published report, the most important advantage of the technique presented here is that perfusion of 70% of the liver is maintained throughout the whole procedure. The establishment of this technique provides a foundation for in vivo partial liver engineering in rats, including decellularization and recellularization.

A Novel Surgical Technique As a Foundation for In Vivo Partial Liver Engineering in Rat

We establish a novel surgical technique for an in vivo single liver lobe perfusion model in rat as a prerequisite for further studying in vivo partial liver engineering in the future.

Vivo에서 부분 간 엔지니어링을에서 위한 쥐를 기초로 새로운 수술 기법

Organ engineering is a novel strategy to generate liver organ substitutes that can potentially be used in transplantation. Recently, in vivo liver ...

Rapid Fabrication of Custom Microfluidic Devices for Research and Educational Applications

Microfluidic devices allow for the manipulation of fluids, particles, cells, micro-sized organs or organisms in channels ranging from the nano to submillimeter scales. A rapid increase in the use of this technology in the biological sciences has prompted a need for methods that are accessible to a wide range of research groups. Current fabrication standards, such as PDMS bonding, require expensive and time consuming lithographic and bonding techniques. A viable alternative is the use of equipment and materials that are easily affordable, require minimal expertise and allow for the rapid iteration of designs. In this work we describe a protocol for designing and producing PET-laminates (PETLs), microfluidic devices that are inexpensive, easy to fabricate, and consume significantly less time to generate than other approaches to microfluidics technology. They consist of thermally bonded film sheets, in which channels and other features are defined using a craft cutter. PETLs solve field-specific technical challenges while dramatically reducing obstacles to adoption. This approach facilitates the accessibility of microfluidics devices in both research and educational settings, providing a reliable platform for new methods of inquiry.

Here we present a protocol to design and fabricate custom microfluidic devices with minimal financial and time investment. The aim is to facilitate the adoption of microfluidic technologies in biomedical research laboratories and educational settings.

연구 및 교육 응용 프로그램을 위한 맞춤형 미세 유체 장치의 신속한 제조

Microfluidic devices allow for the manipulation of fluids, particles, cells, micro-sized organs or organisms in channels ranging from the nano to ...

Electric and Magnetic Field Devices for Stimulation of Biological Tissues

Electric fields (EFs) and magnetic fields (MFs) have been widely used by tissue engineering to improve cell dynamics such as proliferation, migration, differentiation, morphology, and molecular synthesis. However, variables such stimuli strength and stimulation times need to be considered when stimulating either cells, tissues or scaffolds. Given that EFs and MFs vary according to cellular response, it remains unclear how to build devices that generate adequate biophysical stimuli to stimulate biological samples. In fact, there is a lack of evidence regarding the calculation and distribution when biophysical stimuli are applied. This protocol is focused on the design and manufacture of devices to generate EFs and MFs and implementation of a computational methodology to predict biophysical stimuli distribution inside and outside of biological samples. The EF device was composed of two parallel stainless-steel electrodes located at the top and bottom of biological cultures. Electrodes were connected to an oscillator to generate voltages (50, 100, 150 and 200 Vp-p) at 60 kHz. The MF device was composed of a coil, which was energized with a transformer to generate a current (1 A) and voltage (6 V) at 60 Hz. A polymethyl methacrylate support was built to locate the biological cultures in the middle of the coil. The computational simulation elucidated the homogeneous distribution of EFs and MFs inside and outside of biological tissues. This computational model is a promising tool that can modify parameters such as voltages, frequencies, tissue morphologies, well plate types, electrodes and coil size to estimate the EFs and MFs to achieve a cellular response.

This protocol describes the step-by-step process to build both electrical and magnetic stimulators used to stimulate biological tissues. The protocol includes a guideline to simulate computationally electric and magnetic fields and manufacture of stimulator devices.

생물학적 조직의 자극을 위한 전기 및 자기장 장치

Electric fields (EFs) and magnetic fields (MFs) have been widely used by tissue engineering to improve cell dynamics such as proliferation, migration, ...

Formulating and Characterizing Lipid Nanoparticles for Gene Delivery using a Microfluidic Mixing Platform

Lipid-based drug carriers have been used for clinically and commercially available delivery systems due to their small size, biocompatibility, and high encapsulation efficiency. Use of lipid nanoparticles (LNPs) to encapsulate nucleic acids is advantageous to protect the RNA or DNA from degradation, while also promoting cellular uptake. LNPs often contain multiple lipid components including an ionizable lipid, helper lipid, cholesterol, and polyethylene glycol (PEG) conjugated lipid. LNPs can readily encapsulate nucleic acids due to the ionizable lipid presence, which at low pH is cationic and allows for complexation with negatively charged RNA or DNA. Here LNPs are formed by encapsulating messenger RNA (mRNA) or plasmid DNA (pDNA) using rapid mixing of the lipid components in an organic phase and the nucleic acid component in an aqueous phase. This mixing is performed using a precise microfluidic mixing platform, allowing for nanoparticle self-assembly while maintaining laminar flow. The hydrodynamic size and polydispersity are measured using dynamic light scattering (DLS). The effective surface charge on the LNP is determined by measuring the zeta potential. The encapsulation efficiency is characterized using a fluorescent dye to quantify entrapped nucleic acid. Representative results demonstrate the reproducibility of this method and the influence that different formulation and process parameters have on the developed LNPs.

Lipid nanoparticles are developed using a microfluidic mixing platform approach for mRNA and DNA encapsulation.

미세 유체 혼합 플랫폼을 사용하여 유전자 전달을 위한 지질 나노 입자 제조 및 특성화

Lipid-based drug carriers have been used for clinically and commercially available delivery systems due to their small size, biocompatibility, and high ...

Evaluation of Cardiac Contractility Modulation Therapy in 2D Human Stem Cell-Derived Cardiomyocytes

Human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) are currently being explored for multiple in vitro applications and have been used in regulatory submissions. Here, we extend their use to cardiac medical device safety or performance assessments. We developed a novel method to evaluate cardiac medical device contractile properties in robustly contracting 2D hiPSC-CMs monolayers plated on a flexible extracellular matrix (ECM)-based hydrogel substrate. This tool enables the quantification of the effects of cardiac electrophysiology device signals on human cardiac function (e.g., contractile properties) with standard laboratory equipment. The 2D hiPSC-CM monolayers were cultured for 2-4 days on a flexible hydrogel substrate in a 48-well format.
The hiPSC-CMs were exposed to standard cardiac contractility modulation (CCM) medical device electrical signals and compared to control (i.e., pacing only) hiPSC-CMs. The baseline contractile properties of the 2D hiPSC-CMs were quantified by video-based detection analysis based on pixel displacement. The CCM-stimulated 2D hiPSC-CMs plated on the flexible hydrogel substrate displayed significantly enhanced contractile properties relative to baseline (i.e., before CCM stimulation), including an increased peak contraction amplitude and accelerated contraction and relaxation kinetics. Furthermore, the utilization of the flexible hydrogel substrate enables the multiplexing of the video-based cardiac-excitation contraction coupling readouts (i.e., electrophysiology, calcium handling, and contraction) in healthy and diseased hiPSC-CMs. The accurate detection and quantification of the effects of cardiac electrophysiological signals on human cardiac contraction is vital for cardiac medical device development, optimization, and de-risking. This method enables the robust visualization and quantification of the contractile properties of the cardiac syncytium, which should be valuable for nonclinical cardiac medical device safety or effectiveness testing. This paper describes, in detail, the methodology to generate 2D hiPSC-CM hydrogel substrate monolayers.

Here, we demonstrate a non-invasive cardiac medical device contractility evaluation method using 2D human induced pluripotent stem cell-derived cardiomyocyte (hiPSC-CM) monolayers, plated on a flexible substrate, coupled with video-based microscopy. This tool will be useful for the in vitro evaluation of the contractile properties of cardiac electrophysiology devices.

2D 인간 줄기 세포 유래 심근 세포에서 심장 수축성 조절 요법의 평가

Human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) are currently being explored for multiple in vitro applications and have been used ...