Some of the figures in this manuscript were generously provided by the laboratory of Bart O. Williams. The authors are supported by National Cancer Institute grants U54CA143803, CA163124, CA093900, AND CA143055.

This protocol meets and follows the guidelines set by the Johns Hopkins University Institutional Animal Care and Use Committee.
1. Micro-dissecting a Mouse Prostate
<ol>
	<li>Euthanize the mouse by carbon dioxide asphyxiation or an alternative approved method in accordance with institutional animal care and use guidelines.</li>
	<li>Pin the mouse in a supine position to a dissection board by putting a pin through each of the four paws.</li>
	<li>Spray the abdomen with 70% ethanol.</li>
	<li>Hold the skin of the lower abdomen with forceps, and use scissors to cut through the skin and peritoneum approximately 1 cm anterior to the opening of the penis, careful not to cut any organs.</li>
	<li>Cut away the skin and peritoneum from the lower abdomen, up both sides of the abdomen to the rib cage, exposing the peritoneal cavity.</li>
	<li>Identify the bladder and urogenital tract, and expose them by gently moving fat and other organs to the side.</li>
	<li>Using forceps, grip the vas deferens at the base near the urethra, and tear it away.</li>
	<li>Repeat with the opposite vas deferens.</li>
	<li>Using forceps, carefully grip the bladder and pull it up, while simultaneously using scissors to cut through the urethra below the bladder and ventral prostate (approximately 1 cm below the base of the bladder). 
	Note: As the bladder is pulled up, the entire urogenital tract (containing bladder, a section of the urethra, all prostate lobes, and the seminal vesicles) will come with it. There may be some resistance.</li>
	<li>Place the urogenital tract (UGT) into a 60-100 mm Petri dish containing approximately 5-10 ml phosphate buffered saline (PBS).</li>
	<li>Perform the remaining part of the protocol under a dissection microscope. Use two fine forceps, one in each hand. Hold the forceps &#34;like a pencil&#34; and rest the forearms on the bench top so as to steady them.</li>
	<li>Use fine forceps to position the UGT such that the bladder is on top, the urethra is pointed down, and the seminal vesicles are positioned on either side of the bladder.</li>
	<li>Grip the urethra with one forceps and carefully pull away fat with the other forceps without tearing away any prostate tissue. Note: Fat will appear &#34;shiny&#34; relative to the surrounding tissue.</li>
	<li>Once the fat is removed, use forceps to tear the connective tissue between the two ventral lobes of the prostate and separate them.</li>
	<li>To remove one of the ventral lobes, use one forceps to grip a single ventral lobe near the tip, and use the other forceps to grip that lobe at the base as close to the urethra as possible. While still gripping the base of the lobe, use the other forceps to grip the urethra. Pull the lobe away from the urethra with a firm, smooth motion. Make sure no prostate tissue remains attached to the urethra. Place the lobe into the appropriate medium, depending on the next experimental step.
	<ol>
		<li>To fix and paraffin-embed the sample for histological analysis, place the lobe in 10% neutral-buffered formalin (NBF) 8.</li>
		<li>Place the lobe in freezing medium, such as OCT, for cryopreservation and sectioning 8.</li>
		<li>Place the lobe in cold PBS for single cell isolation for culture or flow cytometry 9.</li>
	</ol>
	</li>
	<li>Repeat step 1.15 with the other ventral lobe.</li>
	<li>To remove one of the anterior lobes, use forceps to gently pull the lobe away from the seminal vesicle, making sure not to puncture the seminal vesicle. Once the lobe is independent of the seminal vesicle, remove it in the same fashion as the ventral lobe in step 1.15.</li>
	<li>Repeat step 1.17 with the other anterior lobe.</li>
	<li>Flip the remaining urogenital tract over such that the dorsal prostate is visible.</li>
	<li>To remove one of the dorsolateral lobes, use forceps to tear the connective tissue between the two dorsolateral lobes and also the connective tissue between the lobes and the posterior region of the seminal vesicles. Remove the lobe in a similar fashion as the ventral lobe in step 1.15.</li>
	<li>Repeat step 1.20 with the other dorsolateral lobe.</li>
</ol>
2. Surgical Castration
Note: This is a survival surgery, so asepsis, anesthesia, and pain management are important to the ethical and successful completion of this protocol. Follow all institutional animal care and use guidelines. Use an external heat source, such as a recirculating water blanket, during the surgical procedure to prevent hypothermia. &#160;Do not leave an 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 fully recovered. Autoclave all surgical instruments before use in surgery.
<ol>
	<li>On a clean, sterile surface anesthetize the mouse using appropriate measures (e.g. 2% inhaled isoflurane) and position the mouse in a supine position. Note: Alternative anesthesia methods, such as ketamine, may also be used, depending on the approved animal protocol.</li>
	<li>Check the mouse&#39;s reflexes by pinching the toes. If the mouse does not react, proceed to the next step. If it does react, wait 1-3 min and check again. Shave the surgical area with an electric razor.</li>
	<li>Aseptically prepare the abdomen of the mouse using alternating scrubs of 70% ethanol and iodine or procedures recommended by the institutional veterinary staff or IACUC.</li>
	<li>Using a sterile scalpel, make a 1 cm vertical incision through the skin in the midline of the lower abdomen, approximately 1.5 cm anterior to the penis.</li>
	<li>Make a small incision (&#60;1 cm) through the peritoneum, careful not to cut any organs.</li>
	<li>Using sterile forceps, grip the cut edge of the peritoneum and lift it up gently so as to be able to see the peritoneal cavity beneath.</li>
	<li>Using another sterile forceps, reach into the peritoneal cavity and grip either the left or right testicular fat pad, lateral to the bladder. Pull the fat pad through the opening in the peritoneum and skin until the testis comes out as well. Be careful not to injure any other tissues or organs during this step.</li>
	<li>Using a cautery pen, cut through the fat pad that is holding the testis. Cut slowly through the testicular artery with the cautery pen Note: If the testicular artery is cut too fast, there may be too much bleeding and the mouse may have to be euthanized.</li>
	<li>Once the fat pad and artery are cut, remove the testis and fat pad.</li>
	<li>Repeat steps 2.6-2.9 with the other testis.&#160;Note: An alternative method for removal of the testes is to surgically ligate the testicular artery, followed by cutting the vessel with scissors.</li>
	<li>Suture the peritoneum closed with absorbable suture.</li>
	<li>Staple the skin closed with surgical wound clips.</li>
	<li>Administer an analgesic to manage pain, and place the mouse in a clean cage on a cage warmer for 5-10 min. Monitor the mouse for signs of pain or bleeding.</li>
</ol>

<ol>
	<li>Siegel, R. L., Miller, K. D., Jemal, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cancer+statistics.">Cancer statistics.</a> CA Cancer J Clin. 65 (1), 5-29 (2015).</li><li>Roehrborn, C. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pathology+of+benign+prostatic+hyperplasia.">Pathology of benign prostatic hyperplasia.</a> Int J Impot Res. 20 (suppl 3), 11-18 (2008).</li><li>Valkenburg, K. C., Williams, B. O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mouse+models+of+prostate+cancer.">Mouse models of prostate cancer.</a> Prostate Cancer. , 895238 (2011).</li><li>Shappell, S. B., 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=Prostate+pathology+of+genetically+engineered+mice:+definitions+and+classification.+The+consensus+report+from+the+Bar+Harbor+meeting+of+the+Mouse+Models+of+Human+Cancer+Consortium+Prostate+Pathology+Committee.">Prostate pathology of genetically engineered mice: definitions and classification. The consensus report from the Bar Harbor meeting of the Mouse Models of Human Cancer Consortium Prostate Pathology Committee.</a> Cancer Res. 64 (6), 2270-2305 (2004).</li><li>Valkenburg, K. C., Pienta, K. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Drug+discovery+in+prostate+cancer+mouse+models.">Drug discovery in prostate cancer mouse models.</a> Expert Opin Drug Discov. , 1-14 (2015).</li><li>El-Alfy, M., Pelletier, G., Hermo, L. 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The authors declare that they have no competing financial interests.

Prostate micro-dissection allows for lobe-specific experimentation and analysis of the mouse prostate (Figure 1). In genetically engineered mouse models, phenotypes may be seen in one lobe that is not seen in others. Also, for histological analysis, this protocol assures that the maximum amount of pure prostate tissue can be sectioned and stained, without other urogenital tract tissues present in the section. Finally, for single-cell experiments, this protocol allows for isolation of almost pure prostate...

The prostate is the most common site of cancer in men in the US. Nearly 220,000 men each year will be diagnosed with prostate cancer, and approximately 27,000 men will succumb to their disease 1. Men have a 1 in 7 lifetime risk of a prostate cancer diagnosis in the US 1. Benign prostate hyperplasia (BPH), an age-related noncancerous enlargement of the prostate, is also a widespread condition, affecting over 80% of men over 80 2. As such, the prostate is the focus of considerable research.
Mouse models have been used widely to study diseases of the prostate 3. Overall, the mouse prostate is an excellent representative of the human gland 4, but there are similarities and differences between mouse and human prostate anatomy and physiology 5. In both species, the prostate is located at the base of the bladder, surrounding the urethra. The human prostate gland is a single lobe, split into four zones: central, transition, peripheral, and anterior fibromuscular stroma. In contrast, the mouse prostate consists of three paired lobes at different positions around the urethra: anterior, ventral, and dorsolateral. On a cellular level, the main difference is that the basal cell to luminal cell ratio in human is about 1:1, but it is 1:4 in mice 6. The murine stroma is also different in mice relative to humans &#8211; humans have more extensive smooth muscle, while the muscle layer is much thinner in murine prostate. The proper identification, dissection, and handling of the mouse prostate are essential to mouse prostate research.
Hormone levels drastically affect the development and homeostasis of the prostate gland in both humans and mice. While estrogen seems to play a role in prostate development 7, the most important hormone in the prostate is testosterone. Testosterone is essential for glandular development and maintenance. Following either physical or chemical castration, approximately 90% of the luminal cells in the adult prostate apoptose, and the gland shrinks. If testosterone is reintroduced to an individual under castration conditions, the prostate is able to regenerate itself to full capacity. Testosterone also seems to drive prostate cancer, which is why androgen deprivation therapy is a commonly used therapeutic strategy. However, many prostate cancers become resistant to androgen deprivation. In addition, men undergoing androgen deprivation therapy for treatment of prostate cancer undergo cycles of castrated and regenerated conditions. In the mouse, surgical castration, along with hormonal regeneration of the prostate by reintroducing testosterone, is an important tool with which to study castration resistance and the effects of testosterone cycling on the prostate.
In this article, we will discuss and demonstrate the proper techniques by which to locate and micro-dissect a mouse prostate, as well as to surgically castrate a mouse.

<table border="0" cellpadding="0" cellspacing="0" width="741">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:244px;">Surgical tools</td>
			<td style="width:145px;">Roboz</td>
			<td style="width:113px;">Various</td>
			<td style="width:239px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Formaldehyde</td>
			<td>Sigma</td>
			<td>F8775</td>
			<td></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;">OCT medium</td>
			<td>VWR</td>
			<td>25608-930</td>
			<td style="width:239px;">Must be placed on dry ice to freeze, and stored at -80C</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">PBS</td>
			<td>Life Technologies</td>
			<td align="right">10010</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Isoflurane</td>
			<td>Johns Hopkins</td>
			<td></td>
			<td>Also available from vendors online</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Cautery Pen</td>
			<td>Medline</td>
			<td>ESCT002</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Silk suture</td>
			<td>AD Surgical</td>
			<td>M-S330R19</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Surgical Wound Clips</td>
			<td>Roboz</td>
			<td>RS-9265</td>
			<td></td>
		</tr>
	</tbody>
</table>

murine prostate micro-dissection and surgical castration

Mouse models are used extensively to study prostate cancer and other diseases. The mouse is an excellent model with which to study the prostate and has been used as a surrogate for discoveries in human prostate development and disease. Prostate micro-dissection allows consistent study of lobe-specific prostate anatomy, histology, and cellular characteristics in the absence of contamination of other tissues. Testosterone affects prostate development and disease. Androgen deprivation therapy is a common treatment for prostate cancer patients, but many prostate tumors become castration-resistant. Surgical castration of mouse models allows for the study of castration resistance and other facets of hormonal biology on the prostate. This procedure can be coupled with testosterone reintroduction, or hormonal regeneration of the prostate, a powerful method to study stem cell lineages in the prostate. Together, prostate micro-dissection and surgical castration opens up a multitude of opportunities for robust and consistent research of prostate development and disease. This manuscript describes the protocols for prostate micro-dissection and surgical castration in the laboratory mouse.

All six prostate lobes were removed from a mouse via prostate micro-dissection (Figure 1). The complete urogenital tract (UGT) is composed of all prostate lobes, the bladder, seminal vesicles, and the urethra (Figure 1a). The vas deferens attaches to the urethra, but is unnecessary for prostate micro-dissection, and can thus be detached before removal of the UGT by cutting the urethra (Figure 1b-1c). The urogenital tract will remain toget...

Watch this Scientific Journal Video about Murine Prostate Micro-dissection and Surgical Castration at JoVE.com

Murine Prostate Micro-dissection and Surgical Castration

This manuscript describes the protocols for prostate micro-dissection and surgical castration in the laboratory mouse. We also depict representative results produced by these protocols. Finally, we discuss the advantages and utilization of these protocols.

Mouse models are used extensively to study prostate cancer and other diseases. The mouse is an excellent model with which to study the prostate and has ...

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45.1K Views.  Johns Hopkins University. This manuscript describes the protocols for prostate micro-dissection and surgical castration in the laboratory mouse. We also depict representative results produced by these protocols. Finally, we discuss the advantages and utilization of these protocols.

Video: Murine Prostate Micro-dissection and Surgical Castration

Microvascular Decompression: Salient Surgical Principles and Technical Nuances

Trigeminal neuralgia is a disorder associated with severe episodes of lancinating pain in the distribution of the trigeminal nerve. Previous reports indicate that 80-90% of cases are related to compression of the trigeminal nerve by an adjacent vessel. The majority of patients with trigeminal neuralgia eventually require surgical management in order to achieve remission of symptoms. Surgical options for management include ablative procedures (e.g., radiosurgery, percutaneous radiofrequency lesioning, balloon compression, glycerol rhizolysis, etc.) and microvascular decompression. Ablative procedures fail to address the root cause of the disorder and are less effective at preventing recurrence of symptoms over the long term than microvascular decompression. However, microvascular decompression is inherently more invasive than ablative procedures and is associated with increased surgical risks. Previous studies have demonstrated a correlation between surgeon experience and patient outcome in microvascular decompression. In this series of 59 patients operated on by two neurosurgeons (JSN and PEK) since 2006, 93% of patients demonstrated substantial improvement in their trigeminal neuralgia following the procedure&#x2014;with follow-up ranging from 6 weeks to 2 years. Moreover, 41 of 66 patients (approximately 64%) have been entirely pain-free following the operation.
In this publication, video format is utilized to review the microsurgical pathology of this disorder. Steps of the operative procedure are reviewed and salient principles and technical nuances useful in minimizing complications and maximizing efficacy are discussed.

There are many available options for management of the patient with trigeminal neuralgia. Microvascular decompression, while the most invasive of all options, is also the most effective at achieving long term remission of symptoms. Video instruction on how to maximize efficacy and minimize complications with this procedure is described.

Trigeminal neuralgia is a disorder associated with severe episodes of lancinating pain in the distribution of the trigeminal nerve. Previous reports ...

Evaluation of Nanoparticle Uptake in Tumors in Real Time Using Intravital Imaging

Current technologies for tumor imaging, such as ultrasound, MRI, PET and CT, are unable to yield high-resolution images for the assessment of nanoparticle uptake in tumors at the microscopic level1,2,3, highlighting the utility of a suitable xenograft model in which to perform detailed uptake analyses. Here, we use high-resolution intravital imaging to evaluate nanoparticle uptake in human tumor xenografts in a modified, shell-less chicken embryo model. The chicken embryo model is particularly well-suited for these in vivo analyses because it supports the growth of human tumors, is relatively inexpensive and does not require anesthetization or surgery 4,5. Tumor cells form fully vascularized xenografts within 7 days when implanted into the chorioallantoic membrane (CAM) 6. The resulting tumors are visualized by non-invasive real-time, high-resolution imaging that can be maintained for up to 72 hours with little impact on either the host or tumor systems. Nanoparticles with a wide range of sizes and formulations administered distal to the tumor can be visualized and quantified as they flow through the bloodstream, extravasate from leaky tumor vasculature, and accumulate at the tumor site. We describe here the analysis of nanoparticles derived from Cowpea mosaic virus (CPMV) decorated with near-infrared fluorescent dyes and/or polyethylene glycol polymers (PEG) 7, 8, 9,10,11. Upon intravenous administration, these viral nanoparticles are rapidly internalized by endothelial cells, resulting in global labeling of the vasculature both outside and within the tumor7,12. PEGylation of the viral nanoparticles increases their plasma half-life, extends their time in the circulation, and ultimately enhances their accumulation in tumors via the enhanced permeability and retention (EPR) effect 7, 10,11. The rate and extent of accumulation of nanoparticles in a tumor is measured over time using image analysis software. This technique provides a method to both visualize and quantify nanoparticle dynamics in human tumors.

We present a novel approach to quantify nanoparticle localization in the vasculature of human xenografted tumors using dynamic, real-time intravital imaging in an avian embryo model.

Current technologies for tumor imaging, such as ultrasound, MRI, PET and CT, are unable to yield high-resolution images for the assessment of nanoparticle ...

An Orthotopic Murine Model of Human Prostate Cancer Metastasis

Our laboratory has developed a novel orthotopic implantation model of human prostate cancer (PCa). As PCa death is not due to the primary tumor, but rather the formation of distinct metastasis, the ability to effectively model this progression pre-clinically is of high value. In this model, cells are directly implanted into the ventral lobe of the prostate in Balb/c athymic mice, and allowed to progress for 4-6 weeks. At experiment termination, several distinct endpoints can be measured, such as size and molecular characterization of the primary tumor, the presence and quantification of circulating tumor cells in the blood and bone marrow, and formation of metastasis to the lung. In addition to a variety of endpoints, this model provides a picture of a cells ability to invade and escape the primary organ, enter and survive in the circulatory system, and implant and grow in a secondary site. This model has been used effectively to measure metastatic response to both changes in protein expression as well as to response to small molecule therapeutics, in a short turnaround time.

This orthotopic model of human prostate cancer allows for quantification of tumor size, circulating tumor cells, and formation of distinct metastasis to the lung. As cells must escape the primary organ, enter the blood stream, and implant into a secondary site, this model effectively recapitulates the scenario in humans.

Our laboratory has developed a novel orthotopic implantation model of  human prostate cancer (PCa). As PCa death is not due to the primary tumor, but  ...

Surgical Fixation of Sternal Fractures: Preoperative Planning and a Safe Surgical Technique Using Locked Titanium Plates and Depth Limited Drilling

Different ways to stabilize a sternal fracture are described in literature. Respecting different mechanisms of trauma such as the direct impact to the anterior chest wall or the flexion-compression injury of the trunk, there is a need to retain each sternal fragment in the correct position while neutralizing shearing forces to the sternum. Anterior sternal plating provides the best stability and is therefore increasingly used in most cases. However, many surgeons are reluctant to perform sternal osteosynthesis due to possible complications such as difficulties in preoperative planning, severe injuries to mediastinal organs, or failure of the performed method.
This manuscript describes one possible safe way to stabilize different types of sternal fractures in a step by step guidance for anterior sternal plating using low profile locking titanium plates. Before surgical treatment, a detailed survey of the patient and a three dimensional reconstructed computed tomography is taken out to get detailed information of the fracture&#8217;s morphology. The surgical approach is usually a midline incision. Its position can be described by measuring the distance from upper sternal edge to the fracture and its length can be approximated by the summation of 60 mm for the basis incision, the thickness of presternal soft tissue and the greatest distance between the fragments in case of multiple fractures.
Performing subperiosteal dissection along the sternum while reducing the fracture, using depth limited drilling, and fixing the plates prevents injuries to mediastinal organs and vessels.
Transverse fractures and oblique fractures at the corpus sterni are plated longitudinally, whereas oblique fractures of manubrium, sternocostal separation and any longitudinally fracture needs to be stabilized by a transverse plate from rib to sternum to rib. Usually the high convenience of a patient is seen during follow up as well as a precise reconstruction of the sternal morphology.

Here we present a method to stabilize sternal fractures by using locked titanium plates in a low profile design. Performing subperiosteal dissection along the sternum while reducing the fracture, using depth limited drilling, and fixing the plates provides a safe surgical way.

Different ways to stabilize a sternal fracture are described in literature. Respecting different mechanisms of trauma such as the direct impact to the ...

A Novel Murine Model of Arteriovenous Fistula Failure: The Surgical Procedure in Detail

The arteriovenous fistula (AVF) still suffers from a high number of failures caused by insufficient remodeling and intimal hyperplasia from which the exact pathophysiology remains unknown. In order to unravel the pathophysiology a murine model of AVF-failure was developed in which the configuration of the anastomosis resembles the preferred situation in the clinical setting. A model was described in which an AVF is created by connecting the venous end of the branch of the external jugular vein to the side of the common carotid artery using interrupted sutures. At a histological level, we observed progressive stenotic intimal lesions in the venous outflow tract that is also seen in failed human AVFs. Although this procedure can be technically challenging due to the small dimensions of the animal, we were able to achieve a surgical success rate of 97% after sufficient training. The key advantage of a murine model is the availability of transgenic animals. In view of the different proposed mechanisms that are responsible for AVF failure, disabling genes that might play a role in vascular remodeling can help us to unravel the complex pathophysiology of AVF failure.

Here we present a murine model of arteriovenous fistula (AVF) failure in which a clinically relevant anastomotic configuration is incorporated. This model can be used to study the pathophysiology and to test possible therapeutic interventions.

The arteriovenous fistula (AVF) still suffers from a high number of failures caused by insufficient remodeling and intimal hyperplasia from which the ...

Pre-clinical Orthotopic Murine Model of Human Prostate Cancer

To study the multifaceted biology of prostate cancer, pre-clinical in vivo models offer a range of options to uncover critical biological information about this disease. The human orthotopic prostate cancer xenograft mouse model provides a useful alternative approach for understanding the specific interactions between genetically and molecularly altered tumor cells, their organ microenvironment, and for evaluation of efficacy of therapeutic regimens. This is a well characterized model designed to study the molecular events of primary tumor development and it recapitulates the early events in the metastatic cascade prior to embolism and entry of tumor cells into the circulation. Thus it allows elucidation of molecular mechanisms underlying the initial phase of metastatic disease. In addition, this model can annotate drug targets of clinical relevance and is a valuable tool to study prostate cancer progression. In this manuscript we describe a detailed procedure to establish a human orthotopic prostate cancer xenograft mouse model.

Prostate cancer is the second most common cause of cancer-related deaths in the United States. An orthotopic cancer model provides a useful approach to understand the biology of prostate cancer and to evaluate the efficacy of therapeutic regimens. This protocol describes detailed steps necessary to establish an orthotopic prostate cancer mouse model.

To study the multifaceted biology of prostate cancer, pre-clinical in vivo models offer a range of options to uncover critical biological information ...

Intravital Microscopy of Tumor-associated Vasculature Using Advanced Dorsal Skinfold Window Chambers on Transgenic Fluorescent Mice

Tumor and tumor vessel development, as well as tumor response to therapeutics, are highly dynamic biological processes. Histology provides static information and is often not sufficient for a correct interpretation. Intravital evaluation, in which a process is followed in time, provides extra and often unexpected information. With the creation of transgenic animals expressing cell-specific markers and live cell tracers, improvements to imaging equipment, and the development of several imaging chambers, intravital microscopy has become an important tool to better understand biological processes. This paper describes an experimental design for the investigation of tumor vessel development and of therapeutic effects in a spatial and temporal manner. Using this setup, the stage of vessel development, tip cell and lumen formation, blood flow, extravasation, an established vascular bed, and vascular destruction can be visualized and followed. Furthermore, therapeutic effects, intratumoral fate, and the localization of chemotherapeutic compounds can also be followed.

This protocol describes the intravital imaging of transgenic mice expressing cell-specific fluorescent markers. Intravital imaging provides a non-invasive method for high-resolution observations in living animals using implantable windows through which the microscopic visualization of processes is possible. This method is especially useful to study longitudinal processes.

Tumor and tumor vessel development, as well as tumor response to therapeutics, are highly dynamic biological processes. Histology provides static ...

Using In Vitro Live-cell Imaging to Explore Chemotherapeutics Delivered by Lipid-based Nanoparticles

Conventional imaging techniques can provide detailed information about cellular processes. However, this information is based on static images in an otherwise dynamic system, and successive phases are easily overlooked or misinterpreted. Live-cell imaging and time-lapse microscopy, in which living cells can be followed for hours or even days in a more or less continuous fashion, are therefore very informative. The protocol described here allows for the investigation of the fate of chemotherapeutic nanoparticles after the delivery of doxorubicin (dox) in living cells. Dox is an intercalating agent that must be released from its nanocarrier to become biologically active. In spite of its clinical registration for more than two decades, its uptake, breakdown, and drug release are still not fully understood. This article explores the hypothesis that lipid-based nanoparticles are taken up by the tumor cells and are slowly degraded. Released dox is then translocated to the nucleus. To prevent fixation artifacts, live-cell imaging and time-lapse microscopy, described in this experimental procedure, can be applied.

Using In Vitro Live-cell Imaging to Explore Chemotherapeutics Delivered by Lipid-based Nanoparticles

Live-cell imaging is a powerful tool to visualize dynamic processes. The examination of fixed cells provides only static pictures, which can lead to misinterpretation and confusion about the process. This work presents a method to study uptake, drug release, and intracellular localization of liposomal nanoparticles in living cells.

Conventional imaging techniques can provide detailed information about cellular processes. However, this information is based on static images in an ...

Surgical Treatment for Benign Prostatic Hyperplasia: Holmium Laser Enucleation of the Prostate (HoLEP).

Benign prostatic hyperplasia (BPH) commonly occurs among elderly males. The condition causes symptoms in the lower urinary tract, thereby reducing the quality of life. BPH includes 2 major treatments: medication and surgery. Surgical treatment is often the most effective and final intervention. Holmium laser enucleation of the prostate (HoLEP), one of the most efficient surgical procedures for BPH, is conducted transurethrally. During surgery, the most important and most difficult part is to locate the surgical capsule of the prostate, which is consistent to the idea of anatomic surgery. Different skills may be needed in treating different parts of the prostate. HoLEP tends to be efficient and safe with good hemostatic properties, and able to treat bladder calculus, which may be the complications of BPH. The technique is particularly suitable for prostate of varying volumes and sizes. Indeed, HoLEP also presents certain disadvantages, such as a long learning curve and costly equipment. Regardless, this method may be the "new standard" and the excellent method for the surgical treatment of BPH.

Surgical Treatment for Benign Prostatic Hyperplasia: Holmium Laser Enucleation of the Prostate HoLEP.

Here we present a safe and efficient protocol, holmium laser enucleation of the prostate, to treat benign prostatic hyperplasia.

Benign prostatic hyperplasia (BPH) commonly occurs among elderly males. The condition causes symptoms in the lower urinary tract, thereby reducing the ...

Micro-dissection of Enamel Organ from Mandibular Incisor of Rats Exposed to Environmental Toxicants

Enamel defects resulting from environmental conditions and ways of life are public health concerns because of their high prevalence. These defects result from altered activity of cells responsible for enamel synthesis named ameloblasts, which present in enamel organ. During amelogenesis, ameloblasts follow a specific and precise sequence of events of proliferation, differentiation, and death. A rat continually growing incisors is a suitable experimental model to study ameloblast activity and differentiation stages in physiological and pathological conditions. Here, we describe a reliable and consistent method to micro-dissect enamel organ of rats exposed to environmental toxicants. The micro-dissected dental epithelia contain secretion- and maturation-stage ameloblasts that may be used for qualitative experiments, such as immunohistochemistry assays and in situ hybridization, as well as for quantitative analyses such as RT-qPCR, RNA-seq, and Western blotting.

Understanding enamel formation and possible alterations requires the study of ameloblast activity. Here, we describe a reliable and consistent method to micro-dissect enamel organs containing secretion- and maturation-stage ameloblasts that may be used for further quantitative and qualitative experimental procedures.

Enamel defects resulting from environmental conditions and ways of life are public health concerns because of their high prevalence. These defects result ...