The study was supported by the Art&egrave;res Foundation, the Astellas Foundation Europe and the Boninchi Foundation. CT was supported by the Swiss National Science Foundation (SCORE grant 3232230-126233).

1. Handle: Design and Shaping
<ol>
 <li>Secure an Nr 10 carbon scalpel blade on a wooden board with a tape.</li>
 <li>Tag the center of the ring under the microscope. It should be located 1.2 cm straight from the grove of the scalpel blade.</li>
 <li>Drill a 2 mm hole with a spherical diamond bit, mounted on a high-speed drill.</li>
 <li>Widen the hole with fusiform or conic diamond bits. The final diameter varies according to the rat weight as shown in Table 1.</li>
 <li>Design the shape of the handle with a permanent marker. Figures 1 and 2 can be used as stencils.</li>
 <li>Convert the drill into a mini bench grinder and remove the part of the blade outside the shape.</li>
 <li>Round off the piece with a low speed rotating brush.</li>
</ol>
2. Approximator: Design and Shaping
<ol>
 <li>The approximator is obtained by modifying straight surgical Klemmer's or Kocher's forceps.</li>
 <li>Cut off half of one branch under the microscope using the high-speed mini bench grinder.</li>
 <li>Make symmetrical grooves on both sides to allow for the handle to slide in completely. </li>
 <li>Cut a longitudinal slit in the long arm and check that the center of the long arm and a well-positioned handle are on a same axis. </li>
 <li>Design a notch on the long arm facing the center of the handle. </li>
 <li>Make the branch as thin as possible and round off the piece with the low speed rotating brush. </li>
</ol>
3. Cuffs: Design and Shaping
<ol>
 <li>Cuff calipers vary according to the rat weight and strain. By contrast, their length should be kept around 4 mm. </li>
 <li>Take fine-bore polyethylene tubing and round off one edge with an Nr 10 scalpel. </li>
 <li>Design a grove 0.5 mm from the edge, and carefully cut out a slope going down to the grove. </li>
 <li>Cut out one or two full-thickness nicks into the tubing. These will help manipulating the cuff during graft preparation and transplantation.</li>
 <li>Cut the cuff at 4 mm from its edge. </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>

The authors have nothing to disclose.

The present report describes the design and building of the quick-linker system for easier rat liver transplantation.
Rat liver transplantation is a popular model with 125 to 180 related papers published yearly since the early 1990's (<a href="http://www.pubmed.com" target="_blank">www.pubmed.com</a>). It allows for a wide range of experiments including the exploration of immunological and graft preservation issues. The use of the "quick-linker" kit allows for easier and quicker anastomoses with guaranteed intima-to-intima contact. A detailed description and discussion of the technical steps of a rat liver transplantation have been described previously 1. 
The quick-linker kit can be built at low price from common laboratory material. The main challenge encountered has been related the breakdown of one handle during the final brushing, and that problem has been solved by setting the narrowest part of the handle ring at 0.5 mm (Figures 1 and 2 show appropriate sizes). Regarding the blade quality, only stainless steel should be considered. Although slightly less flexible compared to the average carbon steel blade, stainless steel blades do not develop rust, allowing a lifetime use of the handles. 
Of note, the design of the current handles and cuffs is the result of a process, which has led to the proposed sizes, allowing for the most efficient anastomoses. Cuff diameters vary according to the rat weights (Table 1). Minimal variations can be tolerated in terms of length, with a usual length of about 4 mm (Figures 3 and 4). 
Regarding the approximator, the selected Kocher's forcep should have handles at least 4 cm from the fulcrum. This allows for a safe closure of the rack outside the animal's abdomen. 
Overall, the proposed device can allow easier vein anastomoses for the transplantation of liver and other types of grafts in rats.

A technique of orthotopic rat liver transplantation has been shown in a recent Journal of Visualized Experiments paper 1. Portal vein and infra-hepatic vena cava anastomoses were performed using the quick-linker assisted cuff technique. This technique was chosen among other revisions of the original Kamada's technique 2-4, as it allows for easier and quicker anastomoses, results in a better hemodynamic, and can be implemented with a shorter learning curve 1,5.
The quick-linker technique requires the use of a handle, an approximator and cuffs, all of which can be designed from common laboratory material according to the technique described in the present report.

<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

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 technique allows for easier venous cuff-anatomoses after a reasonable learning curve. The device is composed of two handles, which are carved out from scalpel blades, one approximator, which is obtained by modifying Kocher's forceps, and cuffs designed from fine-bore polyethylene tubing. The whole process can be performed at a low-cost using common laboratory material. The present report provides a step-by-step protocol for the design of the required pieces and includes stencils.

Five kits, including five approximators and 11 handles have been manufactured. One handle broke during the final brushing. This problem was due to the fact that the ring of the handle was too narrow, and it has been solved by setting the narrowest part of the handle ring at 0.5 mm. No problems occurred during the shaping of the approximators.
<table border="1">
<tbody>
 <tr>
 <td>Rat weight 
 (g)</td>
 <td>Porta handle (inner dia) 
 (mm)</td>
 <td>Porta cuff 
 (outer dia) 
 (mm)</td>
 <td>IVC handle (inner dia) 
 (mm)</td>
 <td>IVC cuff 
 (outer dia) 
 (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</td>
 <td>2.42</td>
 <td>4.2</td>
 <td>3.7</td>
 </tr>
 </tbody>
</table>
Table 1.
<img src="/files/ftp_upload/50380/50380fig1.jpg" alt="Figure 1" fo:content-width="6in" fo:src="/files/ftp_upload/50380/50380fig1highres.jpg"/> 
Figure 1. Porta handle stencil. If printed with a scale 1:1 can be used to guide the handle shaping. <a href="https://www.jove.com/files/ftp_upload/50380/50380fig1large.jpg" target="_blank">Click here to view larger figure</a>.
<img src="/files/ftp_upload/50380/50380fig2.jpg" alt="Figure 2" fo:content-width="6in" fo:src="/files/ftp_upload/50380/50380fig2highres.jpg"/> 
Figure 2. IVC handle stencil. If printed with a scale 1:1 can be used to guide the handle shaping. <a href="https://www.jove.com/files/ftp_upload/50380/50380fig2large.jpg" target="_blank">Click here to view larger figure</a>.
<img src="/files/ftp_upload/50380/50380fig3.jpg" alt="Figure 3" fo:content-width="4.6in" fo:src="/files/ftp_upload/50380/50380fig3highres.jpg" /> 
Figure 3. Porta and IVC cuffs lateral view. Graft's v.porta should be secured to the central groove, while recipient's vessel to the lateral one. This expedient allows for optimal intima-to-intima contact.
<img src="/files/ftp_upload/50380/50380fig4.jpg" alt="Figure 4" fo:content-width="4.1in" fo:src="/files/ftp_upload/50380/50380fig4highres.jpg"/> 
Figure 4. Porta and IVC cuffs front view. Calipers suitable for rats weighing 180-270 g are represented.

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

We describe the design of the &#x201C;quick-linker&#x201D; device for easier orthotopic rat liver transplantation.

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 ...

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8.6K Views.  University of Geneva Hospitals. We describe the design of the “quick-linker” device for easier orthotopic rat liver transplantation.

Video: 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
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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

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Paper-based Devices for Isolation and Characterization of Extracellular Vesicles

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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.

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

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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.

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.

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Today, wearable electronics devices combine a large variety of functional, stretchable, and flexible technologies. However, in many cases, these devices cannot be worn under everyday conditions. Therefore, textiles are commonly considered the best substrate to accommodate electronic devices in wearable use. In this paper, we describe how to selectively pattern organic electroactive materials on textiles from a solution in an easy and scalable manner. This versatile deposition technique enables the fabrication of wearable organic electronic devices on clothes.

In this paper, we present a protocol to selectively deposit organic materials on textiles, which allows for the direct integration of organic electronic devices with wearables. The fabricated devices can be fully integrated in textiles, respecting their mechanical appearance and enabling sensing capabilities.

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

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

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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.

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Electric and Magnetic Field Devices for Stimulation of Biological Tissues

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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.

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