The authors have no acknowledgements. Funding was received from the Foundation of Health and Family Planning Commission of Zhejiang Province (Grant 20146242) and the Foundation of Wenzhou Science &amp; Technology Bureau (Grant Y20140248).

All animal experiments were approved by the Animal Research and Care Committee at the Children&#39;s Hospital of Pittsburgh and the University of Pittsburgh Institutional Animal Care and Use Committee.
1. Preoperative Preparation
<ol>
	<li>Administer inhaled isoflurane (1 - 3% for maintenance and up to 5% for induction) via a nose cone to an appropriate anesthetic level. Monitor the adequacy of anesthesia by toe pinch with forceps. The lack of a response is considered adequate, and be sure not to overmedicate, as respiratory depression may occur.</li>
	<li>Place the animal on its back on the dissecting microscope stage, with the abdomen centered in view of the objective. Immobilize the animal with surgical tape. Apply ophthalmic ointment to the eyes of the animal to prevent dryness while under anesthesia.</li>
	<li>Apply a smooth, thick layer of hair removal cream and leave it in place for 3 min. Check a small area for hair removal. Gently wipe off the cream and hair with 70% ethanol-soaked gauze.</li>
	<li>Cleanse and disinfect the abdomen of the animal by wiping it with a 70% ethanol-soaked gauze followed by a betadine-soaked gauze. Maintain sterile conditions throughout the surgical procedure.</li>
</ol>
2. Proper Exposure
<ol>
	<li>Make a midline incision in the skin from the xyphoid process to the umbilicus using a scalpel. Lift the peritoneum with Adson forceps and make a small hole in the midline using scissors.</li>
	<li>Extend the peritoneal incision to the length of the skin incision, taking care to remain on the midline (linea alba). 
	NOTE: This will produce an upper midline abdominal laparotomy.</li>
	<li>Elevate the liver with blunt retractors to expose the common bile duct. Clamp the common bile duct with a curved bulldog vascular clamp. 
	NOTE: This maneuver prevents undesired infusion into the liver.</li>
</ol>
3. Identification of the Pancreatic Papilla and Duodenotomy
<ol>
	<li>Identify the duodenum and, with Arruga forceps, retract it caudally to display the papilla. 
	NOTE: The papilla is a white spot on the anterior surface of the second portion of the duodenum.</li>
	<li>Retract the duodenum caudally, allowing for the identification of the course of the pancreatic duct. With a 30&#189;-gauge needle, puncture the wall of the duodenum tangentially, directly opposite the papilla. 
	NOTE: The needle should follow the same angle as the duct as it enters the duodenum.</li>
</ol>
4. Infusion.
<ol>
	<li>Pass the catheter through the duodenotomy created in step 3.2 until the catheter is visible within the duct. Advance the catheter into the duct no more than 1 cm to prevent the bypass of minor ductal tributaries.</li>
	<li>Clamp the catheter in place with a second curved bulldog vascular clamp. Turn on the pump and infuse the selected volume. The volume infused may range from 25 - 250 &#181;L, with an ideal volume of approximately 150 &#181;L.</li>
	<li>Administer an intraperitoneal injection of approximately 1.5 mL of saline to offset losses. Cover the exposed bowel with a moist gauze to prevent desiccation.</li>
	<li>At the conclusion of the infusion, remove the bulldog clamp that was holding the catheter in place. Use the bulldog clamp to gently remove the catheter from the pancreatic duct. Release the clamp from the common bile duct.</li>
	<li>Close the peritoneum and the skin in one or two layers using a running suture. 
	NOTE: There is no need to close the duodenotomy, as it will seal on its own.</li>
	<li>As postoperative analgesia, administer a dose of ketofen at 5 mg/kg during the procedure and one on the following day.</li>
	<li>Return the mouse to its cage under a heat lamp until it recovers. Provide the mouse with food and water ad libitum.</li>
	<li>Do not leave the animal unattended until it has regained sufficient consciousness to maintain sternal recumbency. Do not return an animal that has undergone surgery to the company of other animals until it has fully recovered.</li>
</ol>
5. Sample Preparation
<ol>
	<li>Place the animal in a carbon dioxide chamber or perform cervical dislocation.</li>
	<li>Harvest the pancreas, with the spleen, liver, and duodenum as controls. Fix the tissues in paraformaldehyde overnight at 4 &#176;C. Cryoprotect the sample in 30% sucrose overnight, as previously described6.</li>
	<li>Snap-freeze the samples. Section the tissue at a thickness of 6 &#181;m using a microtome. Perform imaging on a microscope with fluorescence imaging, as previously described7.</li>
</ol>

<ol>
	<li>Gittes, G. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Developmental+biology+of+the+pancreas:+a+comprehensive+review.">Developmental biology of the pancreas: a comprehensive review.</a> Dev Biol. 326 (1), 4-35 (2009).</li><li>Gu, G., Dubauskaite, J., Melton, D. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Direct+evidence+for+the+pancreatic+lineage:+NGN3++cells+are+islet+progenitors+and+are+distinct+from+duct+progenitors.">Direct evidence for the pancreatic lineage: NGN3+ cells are islet progenitors and are distinct from duct progenitors.</a> Development. 129 (10), 2447-2457 (2002).</li><li>Weinberg, N., Ouziel-Yahalom, L., Knoller, S., Efrat, S., Dor, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Lineage+tracing+evidence+for+in+vitro+dedifferentiation+but+rare+proliferation+of+mouse+pancreatic+beta-cells.">Lineage tracing evidence for in vitro dedifferentiation but rare proliferation of mouse pancreatic beta-cells.</a> Diabetes. 56 (5), 1299-1304 (2007).</li><li>Raper, S. E., DeMatteo, R. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Adenovirus-mediated+in+vivo+gene+transfer+and+expression+in+normal+rat+pancreas.">Adenovirus-mediated in vivo gene transfer and expression in normal rat pancreas.</a> Pancreas. 12 (4), 401-410 (1996).</li><li>Xiao, X., 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=Pancreatic+cell+tracing,+lineage+tagging+and+targeted+genetic+manipulations+in+multiple+cell+types+using+pancreatic+ductal+infusion+of+adeno-associated+viral+vectors+and/or+cell-tagging+dyes.">Pancreatic cell tracing, lineage tagging and targeted genetic manipulations in multiple cell types using pancreatic ductal infusion of adeno-associated viral vectors and/or cell-tagging dyes.</a> Nat Protoc. 9 (12), 2719-2724 (2014).</li><li>Song, Z., 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=EGFR+signaling+regulates+beta+cell+proliferation+in+adult+mice.">EGFR signaling regulates beta cell proliferation in adult mice.</a> J Biol Chem. 291 (43), (2016).</li><li>Xiao, X., 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=M2+macrophages+promote+beta-cell+proliferation+by+up-regulation+of+SMAD7.">M2 macrophages promote beta-cell proliferation by up-regulation of SMAD7.</a> Proc Natl Acad Sci U S A. 111 (13), E1211-E1220 (2014).</li><li>Laukkarinen, J. M., Van Acker, G. J., Weiss, E. R., Steer, M. L., Perides, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+mouse+model+of+acute+biliary+pancreatitis+induced+by+retrograde+pancreatic+duct+infusion+of+Na-taurocholate.">A mouse model of acute biliary pancreatitis induced by retrograde pancreatic duct infusion of Na-taurocholate.</a> Gut. 56 (11), 1590-1598 (2007).</li><li>Lichtenstein, 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=Acute+lung+injury+in+two+experimental+models+of+acute+pancreatitis:+infusion+of+saline+or+sodium+taurocholate+into+the+pancreatic+duct.">Acute lung injury in two experimental models of acute pancreatitis: infusion of saline or sodium taurocholate into the pancreatic duct.</a> Crit Care Med. 28 (5), 1497-1502 (2000).</li><li>Perides, G., van Acker, G. J., Laukkarinen, J. M., Steer, M. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Experimental+acute+biliary+pancreatitis+induced+by+retrograde+infusion+of+bile+acids+into+the+mouse+pancreatic+duct.">Experimental acute biliary pancreatitis induced by retrograde infusion of bile acids into the mouse pancreatic duct.</a> Nat Protoc. 5 (2), 335-341 (2010).</li><li>Guo, P., 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=Specific+transduction+and+labeling+of+pancreatic+ducts+by+targeted+recombinant+viral+infusion+into+mouse+pancreatic+ducts.">Specific transduction and labeling of pancreatic ducts by targeted recombinant viral infusion into mouse pancreatic ducts.</a> Lab Invest. 93 (11), 1241-1253 (2013).</li><li>Xiao, X., 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=Neurogenin3+activation+is+not+sufficient+to+direct+duct-to-beta+cell+transdifferentiation+in+the+adult+pancreas.">Neurogenin3 activation is not sufficient to direct duct-to-beta cell transdifferentiation in the adult pancreas.</a> J Biol Chem. 288 (35), 25297-25308 (2013).</li></ol>

The authors have nothing to disclose.

This work describes in detail the methodology behind pancreatic duct infusion, an effective mouse model for the delivery of genes and other molecules specifically and effectively to the pancreas. Ambiguity in the specifics of the procedure between various groups highlighted the need for a standardized protocol8,9,10.
There are several critical steps of the procedure, beginning with the selection of yo...

The pancreas is a bifunctional organ, with both endocrine and exocrine components. A number of pathologies can afflict the pancreas, including diabetes, pancreatitis, and pancreatic cancer1. All three of these diseases mark active areas of study, not only to develop immediate therapy, but also to better understand their pathophysiology.
A targeted therapeutic delivery method would be beneficial. We have developed a pancreatic duct infusion technique that is an effective and selective method for drug and viral delivery to pancreatic cells. In this model, the pancreatic duct is selectively cannulated, and the common bile duct is occluded, allowing for delivery exclusively to the pancreas.
This technique can allow for the lineage tracing of specific cell types to further elucidate the developmental pathways important to pancreatic development and pathology2,3. Different promoters in viral vectors allow for the specific targeting of cell lines and for the introduction of genes into these cell lines4,5. This work demonstrates the expression of a green fluorescent protein (GFP) within the pancreas after the pancreatic duct infusion of a viral vector expressing GFP versus a sham surgery.

<table border="0" cellpadding="0" cellspacing="0" width="762">
	<tbody>
		<tr height="42">
			<td height="42" style="height:42px;width:288px;">Mice (25-30g, 8-12 weeks old)</td>
			<td style="width:171px;">Jackson Laboratory</td>
			<td style="width:137px;"></td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:288px;">Ketofen</td>
			<td style="width:171px;">Henry Schein Inc.</td>
			<td style="width:137px;">5487</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:288px;">Ethanol (70%)</td>
			<td style="width:171px;">Sigma-Aldrich</td>
			<td style="width:137px;">34923</td>
			<td></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:288px;">Sterile Saline Solution</td>
			<td style="width:171px;">Baxter Healthcare Corp.</td>
			<td style="width:137px;">2B-13-00</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:288px;">Protective Equipment</td>
			<td style="width:171px;"></td>
			<td style="width:137px;"></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:288px;">Hair Removal Product</td>
			<td style="width:171px;"></td>
			<td style="width:137px;"></td>
			<td>Nair or trimmer</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:288px;">Gauze Pads 2in x 2in</td>
			<td style="width:171px;">Fisher Healthcare</td>
			<td style="width:137px;">22-362-178</td>
			<td></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:288px;">Needles (30.5G and 25G)</td>
			<td style="width:171px;">Becton Dicksinson and Co.</td>
			<td style="width:137px;">305106 and 305122</td>
			<td></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:288px;">Syringe for Ketofen and Saline</td>
			<td style="width:171px;">Becton Dicksinson and Co.</td>
			<td style="width:137px;">309657</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:288px;">Syringe for Pump</td>
			<td style="width:171px;">Henke Sass Wolf</td>
			<td style="width:137px;">4010.200V0</td>
			<td></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:288px;">Infusion Pump</td>
			<td style="width:171px;">Pump Systems Inc.</td>
			<td style="width:137px;">NE-1000</td>
			<td></td>
		</tr>
		<tr height="84">
			<td height="84" style="height:84px;width:288px;">Infusion Catheter</td>
			<td style="width:171px;">World Precision Instruments</td>
			<td style="width:137px;">CMF31G</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:288px;">Curved Bulldog Clamps (2)</td>
			<td style="width:171px;">Roboz</td>
			<td style="width:137px;">RS-7439</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:288px;">Arruga Forceps</td>
			<td style="width:171px;">Roboz</td>
			<td style="width:137px;">RS-5163</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:288px;">Adson Forcep</td>
			<td style="width:171px;">Roboz</td>
			<td style="width:137px;">RS-5234</td>
			<td></td>
		</tr>
		<tr height="24">
			<td height="24" style="height:24px;width:288px;">Needle Holder</td>
			<td style="width:171px;">Roboz</td>
			<td>RS-7882</td>
			<td></td>
		</tr>
		<tr height="24">
			<td height="24" style="height:24px;width:288px;">Scissor</td>
			<td style="width:171px;">Roboz</td>
			<td>RS-5982</td>
			<td></td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:288px;">Cotton Tip Applicators</td>
			<td style="width:171px;">Physician Sales and Services</td>
			<td>22-9988</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:288px;">Dissecting Microscope</td>
			<td style="width:171px;"></td>
			<td style="width:137px;"></td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:288px;">Suture</td>
			<td style="width:171px;">Owens and Minor</td>
			<td>SXMD1B402</td>
			<td></td>
		</tr>
	</tbody>
</table>

pancreatic duct infusion: an effective and selective method of drug and viral delivery

The pancreas is a bifunctional organ with both endocrine and exocrine components. A number of pathologies can afflict the pancreas, including diabetes, pancreatitis, and pancreatic cancer. All three of these diseases mark active areas of study, not only to develop immediate therapy, but also to better understand their pathophysiology. There are few tools to further these areas of study. Pancreatic duct infusion is an important technique that can allow for lineage tracing, gene introduction, and cell line-specific targeting. The technique requires the intricate dissection of the second portion of the duodenum and ampulla, followed by the occlusion of the bile duct and the cannulation of the pancreatic duct. Although the technique is technically challenging at first, the applications are myriad. Ambiguity in the specifics of the procedure between groups highlighted the need for a standard protocol. This work describes the expression of a green fluorescent protein (GFP) within the pancreas after the pancreatic duct infusion of a viral vector expressing GFP versus a sham surgery. The infusion and therefore expression is specific to the pancreas, without expression present in any other tissue type.

With practice and careful surgical technique, the survival rate of these mice should be greater than 95%. One week after infusion, the desired effect should be evident in the pancreas. Mice at 10 to 12 weeks of age were utilized for pancreatic duct infusions. Here we use an adeno-associated virus serotype 8 (AAV8) with a CMV promoter to express green fluorescent protein (GFP), as compared to a sham surgery. Mice pancreases were harvested 7 days after the infusions. Sections of pancreas, s...

Watch this Scientific Journal Video about Pancreatic Duct Infusion: An Effective and Selective Method of Drug and Viral Delivery at JoVE.com

Pancreatic Duct Infusion: An Effective and Selective Method of Drug and Viral Delivery

Pancreatic duct infusion is an important technique that can allow for lineage tracing, gene introduction, and cell line-specific targeting. A pancreatic duct infusion technique for drug and viral delivery to pancreatic cells is presented here.

The pancreas is a bifunctional organ with both endocrine and exocrine components. A number of pathologies can afflict the pancreas, including diabetes, ...

pancreatic-duct-infusion-an-effective-selective-method-drug-viral

Research

JoVE Journal

Medicine

4.6K Views.  Children's Hospital of Pittsburgh of UPMC. Pancreatic duct infusion is an important technique that can allow for lineage tracing, gene introduction, and cell line-specific targeting. A pancreatic duct infusion technique for drug and viral delivery to pancreatic cells is presented here.

Video: Pancreatic Duct Infusion: An Effective and Selective Method of Drug and Viral Delivery

An Affordable HIV-1 Drug Resistance Monitoring Method for Resource Limited Settings

HIV-1 drug resistance has the potential to seriously compromise the effectiveness and impact of antiretroviral therapy (ART). As ART programs in sub-Saharan Africa continue to expand, individuals on ART should be closely monitored for the emergence of drug resistance. Surveillance of transmitted drug resistance to track transmission of viral strains already resistant to ART is also critical. Unfortunately, drug resistance testing is still not readily accessible in resource limited settings, because genotyping is expensive and requires sophisticated laboratory and data management infrastructure. An open access genotypic drug resistance monitoring method to manage individuals and assess transmitted drug resistance is described. The method uses free open source software for the interpretation of drug resistance patterns and the generation of individual patient reports. The genotyping protocol has an amplification rate of greater than 95% for plasma samples with a viral load &#62;1,000 HIV-1 RNA copies/ml. The sensitivity decreases significantly for viral loads &#60;1,000 HIV-1 RNA copies/ml. The method described here was validated against a method of HIV-1 drug resistance testing approved by the United States Food and Drug Administration (FDA), the Viroseq genotyping method. Limitations of the method described here include the fact that it is not automated and that it also failed to amplify the circulating recombinant form CRF02_AG from a validation panel of samples, although it amplified subtypes A and B from the same panel.

Drug resistance testing for HIV-1 infected individuals failing antiretroviral therapy (ART) can guide future therapies and improve treatment outcomes. Optimizing individual and population health outcomes in high HIV prevalence but resource-limited settings will ultimately require affordable and accessible drug resistance genotyping and interpretation methods.

HIV-1 drug resistance has the potential to seriously compromise the effectiveness and impact of antiretroviral therapy (ART). As ART programs in ...

Surgical Injury to the Mouse Pancreas through Ligation of the Pancreatic Duct as a Model for Endocrine and Exocrine Reprogramming and Proliferation

Expansion of pancreatic beta cells in vivo or ex vivo, or generation of beta cells by differentiation from an embryonic or adult stem cell, can provide new expandable sources of beta cells to alleviate the donor scarcity in human islet transplantation as therapy for diabetes. Although recent advances have been made towards this aim, mechanisms that regulate beta cell expansion and differentiation from a stem/progenitor cell remain to be characterized. Here, we describe a protocol for an injury model in the adult mouse pancreas that can function as a tool to study mechanisms of tissue remodeling and beta cell proliferation and differentiation. Partial duct ligation (PDL) is an experimentally induced injury of the rodent pancreas involving surgical ligation of the main pancreatic duct resulting in an obstruction of drainage of exocrine products out of the tail region of the pancreas. The inflicted damage induces acinar atrophy, immune cell infiltration and severe tissue remodeling. We have previously reported the activation of Neurogenin (Ngn) 3 expressing endogenous progenitor-like cells and an increase in beta cell proliferation after PDL. Therefore, PDL provides a basis to study signals involved in beta cell dynamics and the properties of an endocrine progenitor in adult pancreas. Since, it still remains largely unclear, which factors and pathways contribute to beta cell neogenesis and proliferation in PDL, a standardized protocol for PDL will allow for comparison across laboratories.

This protocol describes an injury model involving the surgical ligation of the pancreatic duct in the adult mouse pancreas, resulting in severe injury that establishes an environment that allows beta cell neogenesis and proliferation. This model can be used as a tool to study mechanisms involved in beta cell formation.

Expansion of pancreatic beta cells in vivo or ex vivo, or generation of beta cells by differentiation from an embryonic or adult stem cell, can provide ...

An Improved Method for Rapid Intubation of the Trachea in Mice

Despite some anatomical and physiological differences, mouse models continue to be an essential tool for studying human lung disease. Bleomycin toxicity is a commonly used model to study both acute lung injury and fibrosis, and multiple methods have been developed for administering bleomycin (and other toxic agents) into the lungs. However, many of these approaches, such as transtracheal instillation, have inherent drawbacks, including the need for strong anesthetics and survival surgery. This paper reports a quick, reproducible method of intratracheal intubation that involves mild inhaled anesthesia, visualization of the trachea, and the use of a surrogate spirometer to confirm exposure. As a proof of concept, 8-12 week old C57BL/6 mice were administered either 2.0 U/kg of bleomycin or an equivalent volume of PBS, and both damage and fibrotic endpoints were measured post-exposure. This procedure allows researchers to treat a large cohort of mice in a relatively short period with little expense and minimal post-procedure care.

This article presents a rapid and simple method for administering bleomycin directly into the mouse trachea via intubation. Key advantages of this method are that it is highly reproducible, easy to master, and does not require specialized equipment or lengthy recovery times.

Despite some anatomical and physiological differences, mouse models continue to be an essential tool for studying human lung disease. Bleomycin toxicity ...

Modeling and Simulations of Olfactory Drug Delivery with Passive and Active Controls of Nasally Inhaled Pharmaceutical Aerosols

There are many advantages of direct nose-to-brain drug delivery in the treatment of neurological disorders. However, its application is limited by the extremely low delivery efficiency (&#60; 1%) to the olfactory mucosa that directly connects the brain. It is crucial to develop novel techniques to deliver neurological medications more effectively to the olfactory region. The objective of this study is to develop a numerical platform to simulate and improve intranasal olfactory drug delivery. A coupled image-CFD method was presented that synthetized the image-based model development, quality meshing, fluid simulation, and magnetic particle tracking. With this method, performances of three intranasal delivery protocols were numerically assessed and compared. Influences of breathing maneuvers, magnet layout, magnetic field strength, drug release position, and particle size on the olfactory dosage were also numerically studied.
From the simulations, we found that clinically significant olfactory dosage (up to 45%) were feasible using the combination of magnet layout and selective drug release. A 64 -fold higher delivery of dosage was predicted in the case with magnetophoretic guidance compared to the case without it. However, precise guidance of nasally inhaled aerosols to the olfactory region remains challenging due to the unstable nature of magnetophoresis, as well as the high sensitivity of olfactory dosage to patient-, device-, and particle-related factors.

This manuscript reviews the modeling and simulations of different protocols to deliver medications to the olfactory region in image-based nasal airway models. Multiple software modules are used to develop the anatomically accurate nose model, generate computational mesh, simulate nasal airflows, and predict particle deposition at the olfactory region.

There are many advantages of direct nose-to-brain drug delivery in the treatment of neurological disorders. However, its application is limited by the ...

Intraluminal Drug Delivery to the Mouse Arteriovenous Fistula Endothelium

Delivery of therapeutic agents to enhance arteriovenous fistula (AVF) maturation can be administered either via intraluminal or external routes. The simple murine AVF model was combined with intraluminal administration of drug solution to the venous endothelium at the same time as fistula creation. Technical aspects of this model are discussed. Under general anesthesia, an abdominal incision is made and the aorta and inferior vena cava (IVC) are exposed. The infra-renal aorta and IVC are dissected for clamping. After proximal and distal clamping, the puncture site is exposed and a 25 G needle is used to puncture both walls of the aorta and into the IVC. Immediately after the puncture, a reporter gene-expressing viral vector was infused in the IVC via the same needle, followed by 15 min of incubation. The intraluminal administration method enabled more robust viral gene delivery to the venous endothelium compared to administration by the external route. This novel method of delivery will facilitate studies that explore the role of the endothelium in AVF maturation and enable intraluminal drug delivery at the time of surgical operation.

After puncturing the aorta through the inferior vena cava (IVC) to create an aorto-caval fistula in the mouse, solution containing a drug is infused into the IVC via the same needle, followed by incubation. This method enables more robust drug delivery to the venous endothelium compared to the external route.

Delivery of therapeutic agents to enhance arteriovenous fistula (AVF) maturation can be administered either via intraluminal or external routes. The ...

Drug-Induced Sleep Endoscopy (DISE) with Target Controlled Infusion (TCI) and Bispectral Analysis in Obstructive Sleep Apnea

The aim of this study was to establish a standardized protocol for drug-induced sleep endoscopy (DISE) to differentiate obstruction patterns in obstructive sleep apnea (OSA). Target-controlled infusion (TCI) of the sedative propofol was combined with real-time monitoring of the depth of sedation using bispectral analysis.
In an observational study 57 patients (mean age 44.8 years, &#177; SD 10.5; mean apnea hypopnea Index (AHI) 30.8/hr, &#177; SD 21.6, mean BMI 28.2 kg/m2, &#177; SD 5.3) underwent cardiorespiratory polysomnography followed by DISE with TCI and bispectral analysis. Sleep was induced solely by the intravenous infusion of propofol with a TCI-pump, with an initial target plasma level of 2.0 &#181;g/ml. Under continuous monitoring of the patient&#39;s respiration, state of consciousness and value of the bispectral analysis, the target plasma propofol level was raised in steps of 0.2 &#181;g/ml/2 min until the desired depth of sedation was reached. The mean value of the bispectral analysis at the target depth of sedation was determined and the obstruction patterns during DISE-TCI-bispectral analysis then classified according to the VOTE-system. Subsequently the results were analyzed according to polysomnographic and anthropometric data. The occurrence of multilevel obstruction sites across all degrees of severity of OSA clarifies the need for sleep endoscopy prior to upper airway surgery.
The advantage of this technique is the reproducibility of the protocol even for heterogeneous groups of patients. In addition, the gradual controlled and standardized increase of the plasma level of propofol with real-time control of the bispectral index leads to a precisely controllable depth of sedation. The DISE-TCI-bispectral analysis procedure is a step towards a required reproducible protocol of sleep endoscopy &#8212; capable of standardization. However it is not yet known whether these observed obstruction patterns also correspond to findings in natural sleep.

Drug-Induced Sleep Endoscopy DISE with Target Controlled Infusion TCI and Bispectral Analysis in Obstructive Sleep Apnea

The aim of this study was to establish a standardized protocol for sleep endoscopy to differentiate obstruction patterns in obstructive sleep apnea (OSA). Target-controlled infusion (TCI) of the sedative was combined with real-time monitoring of the depth of sedation using bispectral analysis.

The aim of this study was to establish a standardized protocol for drug-induced sleep endoscopy (DISE) to differentiate obstruction patterns in ...

A Novel Method: Super-selective Adrenal Venous Sampling

Primary aldosteronism (PA) and subclinical Cushing&#39;s syndrome (SCS) are conditions in which the adrenal glands autonomously produce excessive amounts of aldosterone and cortisol, respectively. The conventional adrenal venous sampling (cAVS) method collects blood samples from both adrenal central veins and is useful for identifying the laterality of excess hormone production in a unilateral lesion(s), as documented in PA cases. In cAVS, plasma cortisol concentrations (PCCs) are used to normalize plasma aldosterone concentrations (PACs). A novel &#34;super-selective&#34; adrenal venous sampling (ssAVS) method was developed using a micro-catheter, which collects blood samples from adrenal tributary veins (TVs). PACs in ssAVS samples do not require PCC normalization because samples contain a limited amount of systemic venous blood, if any. The ssAVS method enabled segmental lesion(s) to be detected in both adrenal glands, which may be treated by bilateral adrenalectomy, thereby sparing lesion-free segment(s). Right and left adrenals typically have three TVs each, i.e., the superior, lateral, and inferior TVs in the right adrenal as well as the superior-median, superior-lateral, and lateral TVs in the left adrenal. In the ssAVS method, specific parent catheters and a technique to handle them are required, and have been described herein. Furthermore, ssAVS results from three cases of PA are presented: bilateral aldosterone-producing adenoma (APA) (Case #1), left APA and right possible cortisol-producing adenoma causing SCS (Case #2), and idiopathic hyperaldosteronism in which bilateral adrenal segments produced excessive amounts of aldosterone (Case #3). The ssAVS method is not difficult for expert angiographers, and, thus, is recommended worldwide to treat PA cases for which cAVS does not represent a viable surgical treatment option.

&#39;Super-selective&#39; adrenal venous sampling (ssAVS, also called segmental adrenal venous sampling: sAVS)&#160;was performed using a micro-catheter to identify adrenal segment(s) that produce excessive amounts of hormones. The ssAVS technique was described, cases in which adrenal segmental lesion(s) were identified by ssAVS were presented, and the usefulness of ssAVS in future adrenal research was discussed.

Primary aldosteronism (PA) and subclinical Cushing&#39;s syndrome (SCS) are conditions in which the adrenal glands autonomously produce excessive amounts ...

Optimized LC-MS/MS Method for the High-throughput Analysis of Clinical Samples of Ivacaftor, Its Major Metabolites, and Lumacaftor in Biological Fluids of Cystic Fibrosis Patients

Defects in the cystic fibrosis trans-membrane conductance regulator (CFTR) are the cause of cystic fibrosis (CF), a disease with life-threatening pulmonary manifestations. Ivacaftor (IVA) and ivacaftor-lumacaftor (LUMA) combination are two new breakthrough CF drugs that directly modulate the activity and trafficking of the defective CFTR-protein. However, there is still a dearth of understanding on pharmacokinetic/pharmacodynamic parameters and the pharmacology of ivacaftor and lumacaftor. The HPLC-MS technique for the simultaneous analysis of the concentrations of ivacaftor, hydroxymethyl-ivacaftor, ivacaftor-carboxylate, and lumacaftor in biological fluids in patients receiving standard ivacaftor or ivacaftor-lumacaftor combination therapy has previously been developed by our group and partially validated to FDA standards. However, to allow the high-throughput analysis of a larger number of patient samples, our group has optimized the reported method through the use of a smaller pore size reverse-phase chromatography column (2.6 &#181;m, C8 100 &#197;; 50 x 2.1 mm) and a gradient solvent system (0-1 min: 40% B; 1-2 min: 40-70% B; 2-2.7 min: held at 70% B; 2.7-2.8 min: 70-90% B; 2.8-4.0 min: 90% B washing; 4.0-4.1 min: 90-40% B; 4.1-6.0 min: held at 40% B) instead of an isocratic elution. The goal of this study was to reduce the HPLC-MS analysis time per sample dramatically from ~15 min to only 6 min per sample, which is essential for the analysis of a large amount of patient samples. This expedient method will be of considerable utility for studies into the exposure-response relationships of these breakthrough CF drugs.

Ivacaftor and ivacaftor-lumacaftor combination are two new CF drugs. However, there is still a dearth of understanding on their PK/PD and pharmacology. We present an optimized HPLC-MS technique for the simultaneous analysis of ivacaftor and its major metabolites, and lumacaftor.

Defects in the cystic fibrosis trans-membrane conductance regulator (CFTR) are the cause of cystic fibrosis (CF), a disease with life-threatening ...

Improved Method for the Establishment of an In Vitro Blood-Brain Barrier Model Based on Porcine Brain Endothelial Cells

The aim of this protocol presents an optimized procedure for the purification and cultivation of pBECs and to establish in vitro blood-brain barrier (BBB) models based on pBECs in mono-culture (MC), MC with astrocyte-conditioned medium (ACM), and non-contact co-culture (NCC) with astrocytes of porcine or rat origin. pBECs were isolated and cultured from fragments of capillaries from the brain cortices of domestic pigs 5-6 months old. These fragments were purified by careful removal of meninges, isolation and homogenization of grey matter, filtration, enzymatic digestion, and centrifugation. To further eliminate contaminating cells, the capillary fragments were cultured with puromycin-containing medium. When 60-95% confluent, pBECs growing from the capillary fragments were passaged to permeable membrane filter inserts and established in the models. To increase barrier tightness and BBB characteristic phenotype of pBECs, the cells were treated with the following differentiation factors: membrane permeant 8-CPT-cAMP (here abbreviated cAMP), hydrocortisone, and a phosphodiesterase inhibitor, RO-20-1724 (RO). The procedure was carried out over a period of 9-11 days, and when establishing the NCC model, the astrocytes were cultured 2-8 weeks in advance. Adherence to the described procedures in the protocol has allowed the establishment of endothelial layers with highly restricted paracellular permeability, with the NCC model showing an average transendothelial electrical resistance (TEER) of 1249 &#177; 80 &#937; cm2, and paracellular permeability (Papp) for Lucifer Yellow of 0.90 10-6 &#177; 0.13 10-6 cm sec-1 (mean &#177; SEM, n=55). Further evaluation of this pBEC phenotype showed good expression of the tight junctional proteins claudin 5, ZO-1, occludin and adherens junction protein p120 catenin. The model presented can be used for a range of studies of the BBB in health and disease and, with the highly restrictive paracellular permeability, this model is suitable for studies of transport and intracellular trafficking.

Improved Method for the Establishment of an In Vitro Blood-Brain Barrier Model Based on Porcine Brain Endothelial Cells

The aim of the protocol is to present an optimized procedure for the establishment of an in vitro blood-brain barrier (BBB) model based on primary porcine brain endothelial cells (pBECs). The model shows high reproducibility, high tightness, and is suitable for studies of transport and intracellular trafficking in drug discovery.

The aim of this protocol presents an optimized procedure for the purification and cultivation of pBECs and to establish in vitro blood-brain barrier (BBB) ...

Robotic Enucleation of an Intra-Pancreatic Insulinoma in the Pancreatic Head

Pancreatic parenchyma sparing surgery for insulinomas avoids the risk of endocrine and exocrine insufficiency, and potential high-risk anastomoses associated with pancreatic resection. Robotic surgery may be used as an alternative for open pancreatic enucleation without compromising dexterity and 3D-vision.
We present the case of a 42-year old woman who presented with sweating, tremor and episodes of hypoglycemia. A fasting test confirmed endogenic insulin overproduction. After inconclusive CT- and MRI imaging, endoscopic ultrasonography showed a hypoechoic lesion, which was fully within the pancreatic head. Although consent was obtained for pancreatoduodenectomy, robotic enucleation seemed feasible. After mobilization, intraoperative ultrasonography was used to identify the lesion and its relation with the pancreatic duct. Dissection was performed using a traction suture, hot shears and bipolar diathermia. A sealant patch was applied for hemostasis and a drain placed. The patient developed a grade B pancreatic fistula for which endoscopic sphincterotomy was performed; the surgical drain could be removed in the outpatient clinic after 20 days. Prospective studies should confirm the short- and long-term benefits of robotic enucleation of insulinomas.

Here, we present a robotic approach to enucleate an insulinoma in the pancreatic head.

Pancreatic Duct Infusion: An Effective and Selective Method of Drug and Viral Delivery

Summary

Explore More Videos

Chapters in this video

An Affordable HIV-1 Drug Resistance Monitoring Method for Resource Limited Settings

Surgical Injury to the Mouse Pancreas through Ligation of the Pancreatic Duct as a Model for Endocrine and Exocrine Reprogramming and Proliferation

An Improved Method for Rapid Intubation of the Trachea in Mice

Modeling and Simulations of Olfactory Drug Delivery with Passive and Active Controls of Nasally Inhaled Pharmaceutical Aerosols

Intraluminal Drug Delivery to the Mouse Arteriovenous Fistula Endothelium

Drug-Induced Sleep Endoscopy (DISE) with Target Controlled Infusion (TCI) and Bispectral Analysis in Obstructive Sleep Apnea

A Novel Method: Super-selective Adrenal Venous Sampling

Optimized LC-MS/MS Method for the High-throughput Analysis of Clinical Samples of Ivacaftor, Its Major Metabolites, and Lumacaftor in Biological Fluids of Cystic Fibrosis Patients

Improved Method for the Establishment of an In Vitro Blood-Brain Barrier Model Based on Porcine Brain Endothelial Cells

Robotic Enucleation of an Intra-Pancreatic Insulinoma in the Pancreatic Head