This work was supported by NSFC grant 81800928, Research Funding from the West China School/Hospital of Stomatology Sichuan University (No. RCDWJS2021-1), and the State Key Laboratory of Oral Diseases Open Funding grant SKLOD-R013.

This study was approved by the Institutional Animal Care and Use Committee at the State Key Laboratory of Oral Diseases, Sichuan University. Permission was obtained from relevant local agencies before the experiment. Eight 8-10 week old male Sprague-Dawley (SD) rats, with an average weight of 200-250 g, were used for the present study. The animals were obtained from a commercial source (see Table of Materials). Food and water were provided ad libitum throughout the experimental period.
1. Preoperative preparation for the generation of carbon-nanoparticle-assisted PTX rats
<ol>
	<li>Anesthetize the 8-10 week old rats using 2.0%-2.5% isoflurane inhalation, followed by an intraperitoneal (i.p.) injection of tribromoethanol at 10 mL/kg body weight. Guarantee a sufficient depth of anesthesia by testing the absence of the pupillary light reflex. Use vet ointment on the eyes to prevent dryness while under anesthesia. 
	&#8203;NOTE: Rats that are 8-10 weeks old are recognized as adult rats. However, this modeling method can be used on rats as young as 7 days old.</li>
	<li>Prepare the anesthetized SD rats for surgery by shaving the fur of the ventral neck region in the supine position. Disinfect the operative area using povidone-iodine cotton balls (see Table of Materials).</li>
	<li>Cover the animal with surgical drapes (see Table of Materials), and expose the surgical region, aiming to minimize microbial contamination.</li>
</ol>
2. Parathyroidectomy (PTX)
<ol>
	<li>Start at the midpoint between the two ears, and cut a 2 cm incision longitudinally toward the tail using a surgical scalpel. Dissect the fascia and fat layer successively with sharp, curved, serrated forceps.</li>
	<li>Separate the paratracheal muscles, and expose the trachea using relatively blunt forceps under a stereo microscope at 4x-5x magnification.</li>
	<li>Locate the left and right lobes of the butterfly-shaped thyroid glands by the side of the trachea.</li>
	<li>Inject 1 &#181;L of the carbon nanoparticle suspension (see Table of Materials) beneath the membrane of the thyroid glands using a 10 &#181;L syringe with a 30 G beveled needle. After 5 min, irrigate the operative region with saline to clean the extra carbon nanoparticle suspension covering the thyroid gland membrane. 
	NOTE: The recommended injection point is the mesial portion of the thyroid gland lobe, which has fewer blood vessels. A carbon nanoparticle suspension is commonly used in thyroid surgery due to its ability to detect the lymph nodes. Staining the thyroid glands and leaving the parathyroid glands unstained eases the identification of the latter.</li>
	<li>Check to ensure that the thyroid glands turn black while the parathyroid glands remain unstained in ~5 min. Observe the highlighted parathyroid glands under ordinary light using either the light of a stereo microscope or a table lamp. 
	NOTE: Typically, rodents have two drop-shaped parathyroid glands located on the left and right surfaces of the thyroid glands. Occasionally, additional parathyroid glands may be located further away.</li>
	<li>Precisely cut the unstained parathyroid glands with microsurgery forceps and scissors. Use sterile cotton balls for hemostasis or a gelatin sponge if there is more bleeding.</li>
	<li>Close the muscles, fat layers, and skin, layer by layer, with an interrupted horizontal mattress suture using 6-0 polyglactin 910 sutures (see Table of Materials).</li>
	<li>For the sham group, perform all the steps of the preoperative preparation and PTX except step 2.6. Anesthetize the rats, and separate the tissues above the trachea. Locate the parathyroid glands but do not remove them. Conduct postoperative recovery and observation together with the rats of the PTX group.</li>
</ol>
3. Postoperative recovery and observation
<ol>
	<li>After surgery, place the rats on a thermostatic electric blanket (37 &#176;C) to maintain their body temperature. Inject buprenorphine hydrochloride 0.01 mg/kg subcutaneously (s.c) every 12 h as postoperative analgesia. Transfer the rats to a sterile cage when they begin to move and try to crawl.&#160;</li>
	<li>Closely observe the rats postoperatively for 2 h. Return the rats to the rearing room, observe them routinely, and record their state.</li>
	<li>Draw 10 &#181;L of blood from the tail vein 7 days after the surgery. Measure the serum Ca2+, serum Pi, and serum PTH using appropriate commercial kits (see Table of Materials). A successful parathyroidectomy produces a reduced serum ionized Ca2+ level 2 SD lower than that of sham-operated rats (9.00 mmol/L, n = 16). 
	NOTE: A statistics and graphing software (see Table of Materials) was used for the statistical analysis. A Student&#39;s t-test was used to compare the serum and urinary parameters between the sham and PTX groups. p &#60; 0.05 was considered statistically significant. Serum and urinary Ca2+ and Pi and serum urea and creatinine were measured with commercial kits according to the manufacturers&#39; instructions (see Table of Materials). Serum C-telopeptide of type I collagen and osteocalcin were measured with commercially available ELISA kits (see Table of Materials).</li>
</ol>

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The authors declare that they have no competing financial interests.

Epidemiological reports indicate that the detection of thyroid diseases has increased significantly, and the number of related surgeries performed has increased accordingly19,20. The incidence rate of postsurgical hypoparathyroidism is approximately 7.6%8,21, while the increased morbidity of acquired hypoparathyroidism has caused this rare disease to gain greater research attention. It is, therefore, part...

Parathyroid hormone (PTH) is secreted by the parathyroid glands. It is a major modulator of the calcium balance, maintains phosphate metabolism, and participates in bone turnover1,2. Hypoparathyroidism (HypoPT) manifests as a decreased secretion or functional loss of PTH. It is a rare endocrine disorder, with a prevalence of approximately 9-37 per 100,000 person-years3,4,5. HypoPT is characterized by decreased serum PTH and calcium levels accompanied by increased serum phosphorus6,7. HypoPT is classified based on its cause: acquired hypoparathyroidism (AHypoPT) or idiopathic hypoparathyroidism (IHypoPT)8. AHypoPT is more commonly encountered in clinical practice; about 75% of AHypoPT cases are caused by resection or accidental injury of the parathyroid glands during thyroid surgery or other head and neck surgeries. Other causes include radiotherapy and chemotherapy for head and neck tumors and drug toxicity1,8. Upgraded diagnostic methods and an increase in screening for thyroid gland-associated diseases have increased the number of thyroid gland surgical operations. This has led to a corresponding increase in the related parathyroid gland complications9,10.
Easily established animal models with stable characteristics are needed to better investigate AHypoPT and verify the therapeutic effectiveness of novel treatments. Parathyroidectomy (PTX) performed on rats and mice has been reported in previous studies6,11; however, due to the extremely small size of the parathyroid glands and the variability in their anatomical distribution, the success rate is relatively low in practice. Thus, thyro-parathyroidectomy (TPTX) (i.e., the total removal of the thyroid and parathyroid glands) is usually performed to ensure the resection of the parathyroid glands12. However, the resulting low thyroxine levels may complicate studies with this animal model13. HypoPT models established by other methods, such as drug stimulation and gene editing, cannot properly represent the most common AHypoPT pathogenesis. Our group previously used knockout mouse models to label the parathyroid glands and allow the removal of the parathyroid glands without damaging the thyroid glands and surrounding anatomical structures14,15. However, this method utilizes transgenic mouse models, which require a longer development time due to the mating and breeding requirements.
Therefore, we aimed to establish an easily generated model of AHypoPT. This study describes a rat model for PTX using carbon nanoparticle labeling. A carbon nanoparticle suspension of 50 mg/mL, which is commonly used in thyroid surgery, evenly distributes in the thyroid glands after local injection16. The thyroid glands turn black, but the parathyroid glands are left unstained17, thus clearly distinguishing the parathyroid glands from the thyroid glands and allowing the PTX to be performed without affecting the thyroid glands. This method is suitable for rats of different ages. The injection of the carbon nanoparticle suspension is safe and has a negligible effect on thyroid function18. The carbon nanoparticle-labeled PTX rat model generated in this study showed significant hypocalcemia and hyperphosphatemia phenotypes during the 4 week observation period. Thus, this AHypoPT model is easy to establish and has a reproducible phenotype.

<table><tbody><tr><td>0.9% Sodium Chloride Solution</td><td>Kelun Co. Sichuan, China</td><td></td><td></td></tr><tr><td>10 &amp;micro;L 30G NanoFil Syringe</td><td>WPI</td><td></td><td></td></tr><tr><td>6-0 polyglactin 910 suture with needle</td><td>Ethicon, Inc</td><td>J510G</td><td></td></tr><tr><td>Calcium LiquiColor test</td><td>EKF</td><td>0155-225</td><td>For Ca&lt;sup&gt;2+&lt;/sup&gt; analysis</td></tr><tr><td>Carbon Nanoparticles Suspension Injection</td><td>Lummy, Chongqing, China</td><td>H20073246</td><td>1 mL : 50 mg</td></tr><tr><td>Creatinine (Cr) Assay kit ( sarcosine oxidase )</td><td>Jiancheng, Nanjing, China</td><td>C011-2-1</td><td>For creatinine analysis</td></tr><tr><td>Disposable Scalpel</td><td>Shinva, China</td><td></td><td></td></tr><tr><td>Dumstar Biology forceps</td><td>Shinva, China</td><td></td><td></td></tr><tr><td>Micro Dissecting Spring Scissors</td><td>Shinva, China</td><td></td><td></td></tr><tr><td>MicroVue Rat intact PTH ELISA</td><td>Immunotopics</td><td>30-2531</td><td>For the measurement of PTH in rat serum</td></tr><tr><td>Needle Holder</td><td>Shinva, China</td><td></td><td></td></tr><tr><td>Phosphorus Liqui-UV test</td><td>EKF</td><td>0830-125</td><td>For Pi analysis</td></tr><tr><td>Ply gauze</td><td>Weian Co. Henan, China</td><td></td><td></td></tr><tr><td>Povidone-Iodine</td><td>Yongan pharmaceutical Co.Ltd. Chengdu, China</td><td></td><td></td></tr><tr><td>Prism 9.0 (statistics and graphing software)</td><td>GraphPad Software, Inc., San Diego, CA, USA</td><td></td><td>https://www.graphpad.com/scientific-software/prism/</td></tr><tr><td>Rat C-telopeptide of type I collagen (CTX-I) ELISA Kit</td><td>CUSABIO, Wuhan, China</td><td>CSB-E12776r</td><td>For CTX-I analysis</td></tr><tr><td>Rat Osteocalcin/Bone Gla Protein (OT/BGP) ELISA Kit</td><td>CUSABIO, Wuhan, China</td><td>CSB-E05129r</td><td>For osteocalcin analysis</td></tr><tr><td>Safety Single Edge Razor Blades</td><td>American Safety Razor Company</td><td>66-0089</td><td></td></tr><tr><td>Sprague-Dawley Rats</td><td></td><td></td><td>8 to 10 weeks old</td></tr><tr><td>Surgical Incise Drapes</td><td>Liangyou Co. Sichuan, China</td><td></td><td></td></tr><tr><td>Urea Assay Kit</td><td>Jiancheng, Nanjing, China</td><td>C013-2-1</td><td>For urea analysis</td></tr></tbody></table>

generation of hypoparathyroid rats via carbon-nanoparticle-assisted parathyroidectomy

Hypoparathyroidism (HypoPT) is a rare disease involving the parathyroid glands that is characterized by a reduced secretion or potency of the parathyroid hormone (PTH), which leads to high serum phosphorus levels and low serum calcium levels. HypoPT most commonly results from accidental damage to the glands or their removal during thyroid or other anterior neck surgery. Parathyroid/thyroid surgery has become more common in recent years, with a corresponding rise in the occurrence of HypoPT as a postoperative complication. There is a critical need for a HypoPT animal model to better understand the mechanisms underlying the effects of HypoPT on mineral ion homeostasis and to verify the therapeutic effectiveness of novel treatments. Here, a technique is reported to create acquired HypoPT in male rats by performing parathyroidectomy (PTX) using carbon nanoparticles. The rat model shows great promise over the mouse models of hypoparathyroidism.&#160;Importantly, the human PTH receptor binding region has an 84.2% sequence similarity with that of the rat, which is higher than the 73.7% similarity shared with mice. Moreover, the effects of estrogen, which can affect the PTH/PTHrP receptor signaling pathway, have not been fully investigated in male rats. Carbon nanoparticles are lymphatic tracers that stain the thyroid lymph nodes black without affecting their function, but they do not stain the parathyroid glands, which makes them easy to identify and remove. In this study, serum PTH levels were undetectable after PTX, and this resulted in significant hypocalcemia and hyperphosphatemia. Thus, the clinical state of postoperative HypoPT can be remarkably represented in the rat model. Carbon-nanoparticle-assisted PTX can, therefore, serve as an extraordinarily effective and readily implementable model for studying the pathogenesis, treatment, and prognosis of HypoPT.

The locations and number of parathyroid glands were initially observed in rats under a dissection microscope. Before the carbon nanoparticle injection, the thyroid glands were a translucent red color, and the parathyroid glands were hardly distinguishable under the microscope (Figure 1A). After the nanoparticle injection, the thyroid glands were stained black, while the parathyroid glands remained unstained (Figure 1B). The careful dissection of the light-colore...

Watch this Scientific Journal Video about Generation of Hypoparathyroid Rats via Carbon-Nanoparticle-Assisted Parathyroidectomy at JoVE.com

Generation of Hypoparathyroid Rats via Carbon-Nanoparticle-Assisted Parathyroidectomy

An animal model of acquired hypoparathyroidism (HypoPT) is crucial to understanding how HypoPT affects mineral ion homeostasis and to verify the effectiveness of novel treatments. Here, a technique is presented to generate an acquired hypoparathyroidism (AHypoPT) rat model by parathyroidectomy (PTX) using carbon nanoparticles.

Generation of Hypoparathyroid Rats via Carbon-Nanoparticle-Assisted Parathyroidectomy

Hypoparathyroidism (HypoPT) is a rare disease involving the parathyroid glands that is characterized by a reduced secretion or potency of the parathyroid ...

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1.8K Views.  Sichuan University. Het algemene doel van dit protocol is om een rattenmodel van verworven hypoparathyreoïdie te genereren dat gemakkelijk vast te stellen, stabiel van karakter en onschadelijk voor de schildklier is. Het belangrijkste voordeel van dit model is de nauwkeurige verwijdering van bijschildklieren met behulp van koolstofnanodeeltjes. We hopen dat het model kan helpen bij het oplossen van een paar vragen op het gebied van hypoparathyreoïdie.Bijvoorbeeld preoperatief gebruik van calcium en vita...

Video: Generation of Hypoparathyroid Rats via Carbon-Nanoparticle-Assisted Parathyroidectomy

Renal Capsule Xenografting and Subcutaneous Pellet Implantation for the Evaluation of Prostate Carcinogenesis and Benign Prostatic Hyperplasia

New therapies for two common prostate diseases, prostate cancer (PrCa) and benign prostatic hyperplasia (BPH), depend critically on experiments evaluating their hormonal regulation. Sex steroid hormones (notably androgens and estrogens) are important in PrCa and BPH; we probe their respective roles in inducing prostate growth and carcinogenesis in mice with experiments using compressed hormone pellets. Hormone and/or drug pellets are easily manufactured with a pellet press, and surgically implanted into the subcutaneous tissue of the male mouse host. We also describe a protocol for the evaluation of hormonal carcinogenesis by combining subcutaneous hormone pellet implantation with xenografting of prostate cell recombinants under the renal capsule of immunocompromised mice. Moreover, subcutaneous hormone pellet implantation, in combination with renal capsule xenografting of BPH tissue, is useful to better understand hormonal regulation of benign prostate growth, and to test new therapies targeting sex steroid hormone pathways.

We describe the manufacture of compressed hormone pellets, as well as subcutaneous surgical implantation into mice. This strategy can be combined with the growth of cell and tissue xenografts under the renal capsule of athymic nude mice to evaluate hormonal carcinogenesis and regulation of benign prostate growth.

New therapies for two common prostate diseases,  prostate cancer (PrCa) and benign prostatic hyperplasia (BPH), depend  critically on experiments ...

Two-step Approach to Explore Early- and Late-stages of Organ Formation in the Avian Model: The Thymus and Parathyroid Glands Organogenesis Paradigm

The avian embryo, as an experimental model, has been of utmost importance for seminal discoveries in developmental biology. Among several approaches, the formation of quail-chicken chimeras and the use of the chorioallantoic membrane (CAM) to sustain the development of ectopic tissues date back to the last century. Nowadays, the combination of these classical techniques with recent in vitro methodologies offers novel prospects to further explore organ formation.
Here we describe a two-step approach to study early- and late-stages of organogenesis. Briefly, the embryonic region containing the presumptive territory of the organ is isolated from quail embryos and grown in vitro in an organotypic system (up to 48 h). Cultured tissues are subsequently grafted onto the CAM of a chicken embryo. After 10 days of in ovo development, fully formed organs are obtained from grafted tissues. This method also allows the modulation of signaling pathways by the regular administration of pharmacological agents and tissue genetic manipulation throughout in vitro and in ovo developmental steps. Additionally, developing tissues can be collected at any time-window to analyze their gene-expression profile (using quantitative PCR (qPCR), microarrays, etc.) and morphology (assessed with conventional histology and immunochemistry).
The described experimental procedure can be used as a tool to follow organ formation outside the avian embryo, from the early stages of organogenesis to fully formed and functional organs.

This article provides an updated approach to the classical quail-chicken chimera system to study organ formation, by combining novel in vitro and in ovo experimental procedures.

The avian embryo, as an experimental model, has been of utmost importance for seminal discoveries in developmental biology. Among several approaches, the ...

Developmental Biology

Electrically Conductive Scaffold to Modulate and Deliver Stem Cells

Stem cell therapy has emerged as an exciting stroke therapeutic, but the optimal delivery method remains unclear. While the technique of microinjection has been used for decades to deliver stem cells in stroke models, this technique is limited by the lack of ability to manipulate the stem cells prior to injection. This paper details a method of using an electrically conductive polymer scaffold for stem cell delivery. Electrical stimulation of stem cells using a conductive polymer scaffold alters the stem cell's genes involved in cell survival, inflammatory response, and synaptic remodeling. After electrical preconditioning, the stem cells on the scaffold are transplanted intracranially in a distal middle cerebral artery occlusion rat model. This protocol describes a powerful technique to manipulate stem cells via a conductive polymer scaffold and creates a new tool to further develop stem cell-based therapy.

This protocol describes fabrication of a cell culture system to allow seeding of stem cells on a conductive polymer scaffold for in vitro electrical stimulation and subsequent in vivo implantation of the stem cell-seeded scaffold using a minimally invasive technique.

Stem cell therapy has emerged as an exciting stroke therapeutic, but the optimal delivery method remains unclear. While the technique of microinjection ...

Bioengineering

Two Techniques to Create Hypoparathyroid Mice: Parathyroidectomy Using GFP Glands and Diphtheria-Toxin-Mediated Parathyroid Ablation

Hypoparathyroidism (HP) is a disorder characterized by low levels of PTH which lead to hypocalcemia, hyperphosphatemia, and low bone turnover. The most common cause of the disease is accidental removal of the parathyroid glands during thyroid surgery. Novel therapies for HP are needed, but testing them requires reliable animal models of acquired HP. 
Here, we demonstrate the generation of two mouse models of acquired HP. In the GFP-PTX model, mice with green fluorescent protein (GFP) expressed specifically in the parathyroids (PTHcre-mTmG) were created by crossing PTHcre+ mice with Rosa-mTmGfl/fl mice. Green fluorescing parathyroid glands are easily identified under a fluorescence dissecting microscope and parathyroidectomy is performed in less than 20 min. After fluorescence-guided surgery, mice are profoundly hypocalcemic. Contrary to the traditional thyro-parathyroidectomy, this precise surgical approach leaves thyroid glands and thyroid function intact. The second model, which does not require surgery, is based on a diphtheria-toxin approach. PTHcre-iDTR mice, which express the diphtheria toxin (DT) receptor specifically in the parathyroids, were generated by crossing the inducible DTR mouse with the PTHcre mouse. Parathyroid cells are thus rendered sensitive to diphtheria toxin (DT) and can be selectively destroyed by systemically injecting mice with DT. The resulting hypocalcemic phenotype is stable.

Mice with acquired hypoparathyroidism would be useful for studying novel drug therapies for hypoparathyroidism. Two procedures to create such mice are demonstrated. The GFP-PTX mouse is generated by surgical parathyroidectomy guided by green fluorescing parathyroid glands. A second, non-surgical approach is based on parathyroid-specific expression of the diphtheria toxin receptor.

Hypoparathyroidism (HP) is a disorder characterized by low levels of PTH which lead to hypocalcemia, hyperphosphatemia, and low bone turnover. The most ...

Ex Vivo Release of Calcitonin Gene-Related Peptide from the Trigeminovascular System in Rodents

Calcitonin gene-related peptide (CGRP) was first discovered in the 1980s as a splice variant from the calcitonin gene. Since its discovery, its role in migraine pathophysiology has been well established, first by its potent vasodilator properties and subsequently by its presence and function as a neurotransmitter in the sensory trigeminovascular system. The migraine-provoking ability of CGRP gave support to the pharma industry to develop monoclonal antibodies and antagonists inhibiting the effect of CGRP. A new treatment paradigm has proven effective in the prophylactic treatment of migraine. One of the useful tools to further understand migraine mechanisms is the ex vivo model of CGRP release from the trigeminovascular system. It is a relatively simple method that can be used with various pharmacological tools to achieve know-how to further develop new effective migraine treatments. The present protocol describes a CGRP release model and the technique to quantify the effect of pharmacological agents on the amount of CGRP released from the trigeminovascular system in rodents. A procedure describing the experimental approach from euthanasia to the measurement of protein levels is provided. The essential isolation of the trigeminal ganglion and the trigeminal nucleus caudalis from both mice and rats and the preparation of rat dura mater are described in detail. Furthermore, representative results from both species (rats and mice) are presented. The technique is a key tool to investigate the molecular mechanisms involved in migraine pathophysiology by using various pharmacological compounds and genetically modified animals.

Ex Vivo Release of Calcitonin Gene-Related Peptide from the Trigeminovascular System in Rodents

The present protocol describes the ex vivo calcitonin gene-related peptide (CGRP) release model and the strategy to quantify the effect of pharmacological agents on the amount of CGRP released from the trigeminovascular system in rodents.

Calcitonin gene-related peptide (CGRP) was first discovered in the 1980s as a splice variant from the calcitonin gene. Since its discovery, its role in ...

Neuroscience

Establishment of a Simple and Effective Rat Model for Intraoperative Parathyroid Gland Imaging

Parathyroid gland (PG) identification is a critical unmet need in thyroidectomy. The identification of the PG is challenging in thyroid surgery as it is similar in color to the thyroid gland. The lack of effective animal models in preclinical research is a severe limitation for the development of PG identification techniques. This protocol allows for the establishment of a simple and effective rat model for PG identification. In this model, black iron oxide nanoparticles (IONPs) are injected locally in the thyroid gland and rapidly diffuse within the thyroid gland but not the PG. A negatively stained PG and a positively stained thyroid gland can be easily identified by the naked eye without requiring external microscopes. The position of the PG can be identified by increasing the color contrast between the thyroid gland and the PG, based on the color of the black IONPs. This rat model is low-cost and convenient for PG identification, and the IONPs are a novel PG contrast agent.

To date, the development of parathyroid gland (PG) identification methods is limited by the lack of animal models in preclinical research. Here, we establish a simple and effective rat model for intraoperative PG imaging and evaluate its effectiveness by using iron oxide nanoparticles as a novel PG contrast agent.

Parathyroid gland (PG) identification is a critical unmet need in thyroidectomy. The identification of the PG is challenging in thyroid surgery as it is ...

Investigation of the Electrophysiological and Thermographic Safety Parameters of Surgical Energy Devices During Thyroid and Parathyroid Surgery in a Porcine Model

In thyroid and parathyroid surgery, surgical energy devices (SEDs) provide more efficient hemostasis than conventional clamp-and-tie hemostasis in areas with rich blood supply. However, when a SED is activated near the recurrent laryngeal nerve (RLN), the heat generated by the SED may injure the nerve irreversibly. To safely apply SEDs in thyroid/parathyroid surgery, this article introduces experimental porcine model studies to investigate the activation and cooling safety parameters of SEDs in standardized electrophysiological (EP) and thermographic (TG) procedures, respectively. In the EP safety parameter experiments, continuous intraoperative neuromonitoring (C-IONM) is applied to demonstrate the RLN function in real-time. The EP activation study evaluates the safe activation distance of SEDs; the EP cooling study evaluates the safe cooling time of SEDs. In the TG safety parameter experiment, a thermal imaging camera is used to record the temperature change after activating the SED. The TG activation study evaluates the lateral thermal spread distance after SED activation in a dry or humid environment and whether smoke and splashing are generated; the TG cooling study evaluates the cooling time. This will help establish the safety parameters of newly developed SEDs used in thyroid/parathyroid surgery and provide safety guidelines to avoid RLN injury and related complications.

The safe application of newly developed surgical energy devices in thyroid/parathyroid surgery attracts the attention of surgeons. Animal experimental models can avoid unnecessary trials and errors in human surgery. This report aims to demonstrate electrophysiological and thermographic methods to evaluate the safety parameters of SEDs in thyroid/parathyroid surgery.

In thyroid and parathyroid surgery, surgical energy devices (SEDs) provide more efficient hemostasis than conventional clamp-and-tie hemostasis in areas ...

Transoral Endoscopic Thyroidectomy Vestibular Approach for Thyroid Lobectomy

The manuscript describes the transoral endoscopic thyroidectomy vestibular approach (TOETVA) for thyroid lobectomy. The patient is placed in the supine position with extension and fixation of the neck. One 20 mm transverse incision and two 5 mm incisions are made through the mucosa of the oral vestibule for camera and instrument placement after disinfection of the skin and oral cavity. The workspace is established and maintained by the skin suspension device, which is made of unabsorbable string (3-0) and rubber bands, and the CO2 insufflation pressure. Lobectomy using a medial-to-lateral technique and prophylactic ipsilateral central neck dissection is performed simultaneously on patients with papillary thyroid cancer (PTC). The specimen is extracted through the 20 mm incision. The parathyroid gland is immediately searched for in the specimen and auto-transplanted to the left brachioradialis. A drainage tube is inserted through the retractor hole into the bed of the thyroid gland, and absorbable sutures are used to close the mucosal incisions in the oral vestibule and the linea alba cervicalis. Prophylactics administered intravenously are recommended for the first 24 h after surgery, and oral antibiotics are used for 7 days postoperatively.

Here, we present a protocol to describe the methodology for the transoral endoscopic thyroidectomy vestibular approach in detail.

The manuscript describes the transoral endoscopic thyroidectomy vestibular approach (TOETVA) for thyroid lobectomy. The patient is placed in the supine ...

Transoral Robotic Total Thyroidectomy and Bilateral Central Regional Lymph Node Dissection for Papillary Thyroid Carcinoma

Currently, the common approaches to thyroid surgery include conventional thyroidectomy, bilateral axillo-breast, axillary, retroauricular, and oral vestibule approaches. Essentially, various approaches to thyroid surgery only move the traditional surgical incision to a more concealed position but still leave scars on the body surface. Among them, thyroid surgery via the oral vestibule approach can obtain the best cosmetic outcome through the shortest natural cavity. However, in the early time, thyroid surgery via the oral vestibule approach usually requires three incisions in the mouth and one axillary incision. We have introduced a robotic surgical system into thyroidectomy via the oral vestibule approach and successfully completed total thyroidectomy and bilateral central lymph node dissection. During the operation, only three incisions were made at the oral vestibule without an axillary incision. This article aims to present the unique three-port method of robotic thyroidectomy via oral vestibule for the treatment of patients with papillary thyroid cancer.

The transoral robotic total thyroidectomy and bilateral central regional lymph node dissection using three ports without axillary incision are feasible and safe for early-stage papillary thyroid carcinoma. Here we present the operative techniques of this operation.

Currently, the common approaches to thyroid surgery include conventional thyroidectomy, bilateral axillo-breast, axillary, retroauricular, and oral ...

The Creation of a Rat Model for Osteosarcopenia via Ovariectomy

Osteosarcopenia (OS), a complex degenerative disorder, is characterized by the concurrent decline in skeletal muscle mass and bone mineral density (BMD), posing an enormous health hazard for the elderly population. Despite its clinical relevance, the pathophysiological mechanisms underlying OS are not fully understood, underscoring the necessity for a deeper comprehension of its etiology to facilitate effective treatment strategies. The development of a reliable animal model is pivotal in this endeavor. This study presents a refined protocol for the induction of postmenopausal osteosarcopenia in rats through bilateral ovariectomy, a method known to accelerate the onset of age-related muscle and bone loss. In this study, rats aged 12 weeks were stratified by body weight and randomly assigned to either a sham operation group or an ovariectomized (OVX) group. Tissue samples from the quadriceps and triceps muscles of the left hind limb, as well as the left femur, were systematically collected at 4, 8, and 12 weeks post-surgery. This methodical approach ensures a comprehensive evaluation of the effects of ovariectomy on muscle and bone health. Histological evaluation of muscle fiber atrophy and femoral morphology was conducted using hematoxylin and eosin (HE) staining, while bone mineral density was quantified using dual-energy X-ray absorptiometry (DXA). The temporal progression of OS was meticulously monitored at the aforementioned intervals, providing insights into the dynamic interplay between muscle and bone degeneration. This model not only accurately reflects the clinical manifestations of OS but also serves as a robust platform for investigating novel therapeutic approaches and their underlying mechanisms.

This current protocol outlines a procedure for creating a rat model of osteosarcopenia using ovariectomy.

Osteosarcopenia (OS), a complex degenerative disorder, is characterized by the concurrent decline in skeletal muscle mass and bone mineral density (BMD), ...

Generation of Hypoparathyroid Rats via Carbon-Nanoparticle-Assisted Parathyroidectomy

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