eoe sub articles

EoE Sub Articles

All procedures involving animal models have been reviewed by the local institutional animal care committee and the JoVE veterinary review board.
1. Preparation of hemoglobin and CSF solutions
<ol>
	<li>Prepare a sterile artificial cerebrospinal fluid (aCSF) solution by adding 500 &#181;L of the aCSF solution to a 1.5 mL microtube and store on ice.</li>
	<li>Prepare a sterile 150 mg/mL hemoglobin solution by adding 75 mg of hemoglobin to 500 &#181;L of aCSF in a 1.5 mL microtube and store on ice.</li>
</ol>
2. Preparation of the animal for injection
<ol>
	<li>Turn the heating pad to the medium setting to maintain the body temperature of the rat.</li>
	<li>Anesthetize postnatal day 4 (P4) rats in an induction chamber filled with 3% isoflurane. 
	NOTE: Confirm sufficient anesthesia using the toe/tail-pinch response every 15 min. Monitor anesthesia with visual observation of tissue color, body temperature, and respiratory rate.</li>
	<li>Administer pain relief with a 5 mg/kg subcutaneous carprofen injection to the anesthetized rat.</li>
	<li>Place the anesthetized rat prone in the stereotactic apparatus with the nose positioned in the anesthesia adaptor with a constant flow of 1.5% isoflurane.</li>
	<li>Tighten non-rupture ear bars on the external auditory meatus to secure the head. 
	NOTE: Apply vet ointment to keep the eyes moisturized if the eyes are open at the age of injection.</li>
	<li>Clean the head, alternating with sterile cotton-tipped applicators soaked in betadine and 70% ethanol.
	<ol>
		<li>Touch the betadine-soaked applicator to the center of the scalp and spread the betadine in circles, moving outward.</li>
		<li>Repeat step 2.6.1.1 with the ethanol-soaked applicator.</li>
		<li>Repeat step 2.6.1.1 and step 2.6.1.2 3x.</li>
	</ol>
	</li>
	<li>Apply a sterile surgical drape to protect the surgical field.</li>
	<li>Using a sterile scalpel, make a 0.3 cm incision vertically down the center of the head to expose the bregma of the skull. 
	NOTE: If injecting from the lambda, expose the lambda of the skull instead of the bregma.</li>
	<li>Use a sterile cotton-tipped applicator to dry the area.</li>
</ol>
3. Setting up the stereotactic injector
<ol>
	<li>Draw the hemoglobin solution prepared in step 1.2 into a 0.3 mL sterile syringe with a 30G needle and place the syringe into the stereotactic injector system. 
	&#8203;NOTE: If generating control conditions, draw aCSF solution prepared in step 1.1 into a 0.3 mL sterile syringe and proceed with the protocol.</li>
	<li>Turn on the stereotactic injector interface and click on the Configuration button to input the injection volume and rate settings.
	<ol>
		<li>Click on Volume and set the volume at 20,000 nL (20 &#181;L).</li>
		<li>Click on Infusion rate and set the rate at 8,000 nL/min (8 &#181;L/min).</li>
	</ol>
	</li>
	<li>Exit Configuration by clicking on the Reset Pos button.</li>
	<li>Flush the needle tip by clicking on the Infuse button until a small bead of hemoglobin solution emerges at the needle tip.</li>
	<li>Gently wick the hemoglobin solution from the needle tip with a sterile cotton-tipped applicator.</li>
</ol>
4. Animal injection
<ol>
	<li>Set the bregma as zero on the stereotactic injector system by adjusting the mediolateral and anteroposterior positions of the syringe before lowering the tip of the flushed syringe needle to gently touch the skull at the bregma. 
	NOTE: If injecting from the lambda, set lambda as zero.</li>
	<li>Identify the coordinates of choice.
	<ol>
		<li>If injecting from the bregma, in P4 rats described here, use 1.5 mm lateral, 0.4 mm anterior, and 2.0 mm deep from bregma.</li>
		<li>If injecting from the lambda, use the following coordinates for P4 rats: 1.1 mm lateral, 4.6 mm anterior, and 3.3 mm deep from lambda.</li>
	</ol>
	</li>
	<li>Raise the syringe needle 1 cm above the skull to clear the scalp. When the syringe is raised, proceed to set the mediolateral and anteroposterior coordinates.</li>
	<li>Lower the syringe needle to gently touch the skull. Check that the needle is touching the skull.</li>
	<li>Set the dorsoventral coordinate over a 30 s period. 
	NOTE: While setting the dorsoventral coordinate, the needle will puncture the skull. Care must be taken to assure that the syringe passes through the skull without deforming the skull. Skull deformation is avoided by slowly withdrawing the needle along the dorsoventral coordinate if deformation occurs, then placing the needle back along the same trajectory. This allows the needle to pass through the hole in the skull with less force and no deformation.</li>
	<li>On the stereotactic injector interface, click on the Run button to begin injection.</li>
	<li>After the injection is finished, leave the syringe needle in place for 2 min to minimize backflow of the solution.</li>
	<li>Withdraw the syringe slowly along the dorsoventral coordinate over 2 min until the needle tip is 2 cm above the scalp.</li>
	<li>Rotate the stereotactic injector arm away from the operative field.</li>
</ol>
5. Postoperative care
<ol>
	<li>Close the scalp with a 6-0 monofilament suture. Make one simple interrupted suture at the center of the 0.3 cm incision.</li>
	<li>Remove the pup from anesthesia and place it onto a secure area on the heating pad.</li>
	<li>Return the rodent to the home cage to recover from the anesthesia under the care of its dam. 
	NOTE: Timely return to the care of the dam reduces early postoperative mortality.</li>
	<li>Monitor the animals for anesthesia by loss of the righting reflex hourly post-surgery for 3 h.</li>
	<li>Monitor the animals daily for 7 days for normal activity, food intake, and weight gain. Monitor the incision site for wound healing, closure, and reappearance of fur at the site of surgery. 
	NOTE: In the rare case that neurological changes such as seizures, central depression, or decreased appetite are observed during monitoring, euthanize the animal using intravascular perfusion or cervical dislocation under anesthesia.</li>
	<li>To prevent infection once the suture is closed and the wound is healing, apply topical triple-antibiotic at the incision site.</li>
</ol>

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>0.3 mL insulin syringe</td>
			<td>BD Microfine + Insulin Syringe</td>
			<td>230-4533</td>
			<td>0.3-0.5 mL synringes will work</td>
		</tr>
		<tr>
			<td>1.5 mL microtube</td>
			<td>USA Scientific</td>
			<td>1615-5500</td>
			<td>Lot No. K194642H -3 511</td>
		</tr>
		<tr>
			<td>6-0 monofilament suture</td>
			<td>ETHICON</td>
			<td>667G</td>
			<td></td>
		</tr>
		<tr>
			<td>Analytical balance</td>
			<td>CCURIS Instruments</td>
			<td>W3200-320</td>
			<td></td>
		</tr>
		<tr>
			<td>Artificial CSF (aCSF)</td>
			<td>Tocris Bioscience</td>
			<td>3525</td>
			<td>Batch No: 72A</td>
		</tr>
		<tr>
			<td>Betadine</td>
			<td>Purdue Products L.P.</td>
			<td>301005-00</td>
			<td>NDC 67618-150-09</td>
		</tr>
		<tr>
			<td>Carprofen (injectable)</td>
			<td>Zoetis Inc.</td>
			<td>PI 4019448</td>
			<td>Rimadyl</td>
		</tr>
		<tr>
			<td>Ethanol</td>
			<td>Decon Laboratories</td>
			<td>2701</td>
			<td></td>
		</tr>
		<tr>
			<td>Heating pad</td>
			<td>Sunbeam</td>
			<td>E12107-819</td>
			<td>UL 612A, Z-1228-001</td>
		</tr>
		<tr>
			<td>Hemoglobin</td>
			<td>MP Biomedicals</td>
			<td>100714</td>
			<td>LOT NO. SR02321</td>
		</tr>
		<tr>
			<td>Isoflurane</td>
			<td>Piramal Critical Care</td>
			<td>NDC 66794-017-25</td>
			<td></td>
		</tr>
		<tr>
			<td>Isoflurane vaporizer</td>
			<td>VETEQUIP</td>
			<td>911103</td>
			<td></td>
		</tr>
		<tr>
			<td>Light for stereotactic insturment</td>
			<td>Dolan-Jenner industries</td>
			<td>Fiber-Lite MI-150</td>
			<td></td>
		</tr>
		<tr>
			<td>Microinjection syringe pump</td>
			<td>World Precision Instruments</td>
			<td>MICRO21</td>
			<td>Serial 184034 T08K</td>
		</tr>
		<tr>
			<td>Oxygen</td>
			<td>Airgas Healthcare</td>
			<td>UN1072</td>
			<td>LOT NUMBER S1432080XA02</td>
		</tr>
		<tr>
			<td>Sprague Dawley rats</td>
			<td>Charles River Laboratories</td>
			<td>Strain code: 001</td>
			<td></td>
		</tr>
		<tr>
			<td>Stereotactic instrument</td>
			<td>KOPF Instuments</td>
			<td>Model 900LS Lazy Susan</td>
			<td></td>
		</tr>
		<tr>
			<td>Sterile cotton tipped applicator</td>
			<td>Fischerbrand</td>
			<td>23-400-118</td>
			<td></td>
		</tr>
		<tr>
			<td>Surgical blade</td>
			<td>covetrus</td>
			<td>#10</td>
			<td></td>
		</tr>
		<tr>
			<td>Topical triple antibiotic</td>
			<td>Triple Antibiotic Ointment</td>
			<td>NDC 51672-2120-1</td>
			<td></td>
		</tr>
	</tbody>
</table>

modeling neonatal intraventricular hemorrhage through intraventricular injection of hemoglobin

Source: Miller, B. A., et al. <a href="https://app.jove.com/v/63345">Modeling Neonatal Intraventricular Hemorrhage Through Intraventricular Injection of Hemoglobin.</a> J. Vis. Exp. (2022).
This video demonstrates a method to generate a rat model of neonatal intraventricular hemorrhage. In this procedure, an anesthetized rat pup is injected with hemoglobin into the lateral ventricle of the brain. The hemoglobin causes oxidative stress and releases heme, simulating intraventricular hemorrhage. The resulting damage to brain tissues, driven by reactive oxygen species and inflammatory cytokines, leads to ventricular enlargement, a common consequence of intraventricular hemorrhage.

Modeling Neonatal Intraventricular Hemorrhage Through Intraventricular Injection of Hemoglobin

Source: Miller, B. A., et al. Modeling Neonatal Intraventricular Hemorrhage Through Intraventricular Injection of Hemoglobin. J. Vis. Exp. (2022).
This ...

Secure an anesthetized rat pup on a stereotactic frame. Disinfect the head and incise to expose the skull.
Identify the bregma, an anatomical landmark, to locate the lateral ventricles, cerebrospinal fluid-filled cavities in the brain.
Choroid plexus epithelial cells and ependymal cells line the ventricles, forming a barrier from the periventricular space.
Use a microsyringe to inject hemoglobin into a ventricle, mimicking intraventricular hemorrhage.
Withdraw the needle, close the incision, and allow the pup to recover.
Injected hemoglobin undergoes degradation, releasing heme and generating reactive oxygen species or ROS.
ROS oxidize cell membrane lipids and proteins, causing cell death and disrupting the barrier, which allows heme to enter the periventricular space.
Tissue-resident immune cells recognize free heme as a danger signal and release proinflammatory cytokines to recruit additional immune cells, which damage the neighboring brain tissues.
The loss of periventricular tissue leads to ventricular enlargement, a consequence of intraventricular hemorrhage.

modeling-neonatal-intraventricular-hemorrhage-through

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Cerebrovascular Diseases

18 visualizações. Source: Miller, B. A., et al. Modeling Neonatal Intraventricular Hemorrhage Through Intraventricular Injection of Hemoglobin. J. Vis. Exp. (2022). This video demonstrates a method to generate a rat model of neonatal intraventricular hemorrhage. In this procedure, an anesthetized rat pup is injected with hemoglobin into the lateral ventricle of the brain. The hemoglobin causes oxidative stress and releases heme, simulating intraventricular hemorrhage. The resulting damage to brain tissues, drive...

Vídeo: Modeling Neonatal Intraventricular Hemorrhage Through Intraventricular Injection of Hemoglobin - Conceito

Minimally Invasive Endoscopic Intracerebral Hemorrhage Evacuation

Intracerebral hemorrhage (ICH) is a subtype of stroke with high mortality and poor functional outcomes, largely because there are no evidence-based treatment options for this devastating disease process. In the past decade, a number of minimally invasive surgeries have emerged to address this issue, one of which is endoscopic evacuation. Stereotactic ICH Underwater Blood Aspiration (SCUBA) is a novel endoscopic evacuation technique performed in a fluid-filled cavity using an aspiration system to provide an additional degree of freedom during the procedure. The SCUBA procedure utilizes a suction device, endoscope, and sheath and is divided into two phases. The first phase involves maximal aspiration and minimal irrigation to decrease clot burden. The second phase involves increasing irrigation for visibility, decreasing aspiration strength for targeted aspiration without disturbing the cavity wall, and cauterizing any bleeding vessels. Using the endoscope and aspiration wand, this technique aims to maximize hematoma evacuation while minimizing collateral damage to the surrounding brain. Advantages of the SCUBA technique include the use of a low-profile endoscopic sheath minimizing brain disruption and improved visualization with a fluid-filled cavity rather than an air-filled one.

This paper details the surgical protocol for minimally invasive endoscopic intracerebral hemorrhage evacuation using the SCUBA technique.

Evacuação de hemorragia intracerebral endoscópica minimamente invasiva

Intracerebral hemorrhage (ICH) is a subtype of stroke with high mortality and poor functional outcomes, largely because there are no evidence-based ...

JoVE Journal

Neurociência

Massive Pontine Hemorrhage by Dual Injection of Autologous Blood

We provide a protocol to establish a massive pontine hemorrhage model in a rat. Rats weighing about 250 grams were used in this study. One hundred microliters of autologous blood was taken from the tail vein and stereotaxically injected into the pons. The injection process was divided into 2 steps: First, 10 &#181;L of blood was injected into a specific location, anteroposterior position (AP) -9.0 mm; lateral (Lat) 0 mm; vertical (Vert) -9.2 mm, followed by a second injection of the residual blood located at AP -9.0 mm; Lat 0 mm; Vert -9.0 mm with a 20-minute interval. The balance beam test, limb placement test, and the modified Voestch neuroscore were used to evaluate neurological function. Magnetic Resonance Imaging (MRI) was used to assess the volume of hemorrhage in vivo. The symptoms of this model were in line with patients with massive pontine hemorrhage.

We present a protocol to establish a massive pontine hemorrhage model in a rat via dual injection of autologous blood.

Hemorragia pontina maciça por dupla injeção de sangue autólogo

We provide a protocol to establish a massive pontine hemorrhage model in a rat. Rats weighing about 250 grams were used in this study. One hundred ...

Intracranial Pressure Monitoring In Nontraumatic Intraventricular Hemorrhage Rodent Model

Survivors of intraventricular hemorrhage are often left with significant long-term memory impairment; thus, research utilizing intraventricular hemorrhage animal models is essential. In this study, we sought out ways to measure intracranial pressure, mean arterial pressure, and cerebral perfusion pressure during nontraumatic intraventricular hemorrhage in rats. The experimental design included three Sprague Dawley groups: sham, standard 200 &#181;l intraventricular hemorrhage, and vehicle control groups. By introducing an intraparenchymal fiberoptic pressure sensor, precise intracranial pressure measurements were obtained in all groups. Cerebral perfusion pressures were calculated with the knowledge of intracranial pressure and mean arterial pressure values. As expected, the intraventricular hemorrhage and vehicle control groups both experienced a rise in the intracranial pressure and subsequent decline in cerebral perfusion pressure during intraventricular injection of autologous blood and artificial cerebrospinal fluid, respectively. The addition of an intraparenchymal fiberoptic pressure sensor is beneficial in monitoring precise intracranial pressure changes.

Monitoring intracranial pressure in rodent&#160;models of nontraumatic intraventricular hemorrhage is not common in the current literature. Herein, we demonstrate a technique for measuring intracranial pressure, mean arterial pressure, and cerebral perfusion pressure during intraventricular hemorrhage in a rat&#160;animal model.

Monitorização da Pressão Intracraniana em Modelo de Roedor de Hemorragia Intraventricular Não Traumática

Survivors of intraventricular hemorrhage are often left with significant long-term memory impairment; thus, research utilizing intraventricular hemorrhage ...

Modeling Neonatal Intraventricular Hemorrhage Through Intraventricular Injection of Hemoglobin

Transcrição

Modeling Neonatal Intraventricular Hemorrhage Through Intraventricular Injection of Hemoglobin

Evacuação de hemorragia intracerebral endoscópica minimamente invasiva

Hemorragia pontina maciça por dupla injeção de sangue autólogo

Monitorização da Pressão Intracraniana em Modelo de Roedor de Hemorragia Intraventricular Não Traumática