Jove-Journal of Visualized Experiments最新文献

{"title":"Surgical Technique for Lumbar Spinal Catheter Insertion in Pigs Enabling Continuous Access to the Thecal Sac in a Terminal Setup.","authors":"Theis Mariager, Jacob Holmen Terkelsen, Pernille Veiss-Pedersen, Carsten Reidies Bjarkam","doi":"10.3791/67907","DOIUrl":"https://doi.org/10.3791/67907","url":null,"abstract":"<p><p>Pigs are increasingly used as a large animal model for pharmacologic CNS research due to the anatomical and physiological similarities between the porcine and human central nervous systems (CNS). However, accessing the cerebrospinal fluid (CSF) in larger pig breeds by conventional lumbar puncture techniques can be challenging due to an oblique orientation of the spinal spinous processes and a limited interlaminar space. Accordingly, an open surgical procedure for inserting a lumbar spinal catheter for continuous CSF sampling at the L4/L5 level in pigs is thoroughly described in this work. After positioning the pig and identifying the anatomical landmarks, a dorsal midline surgical incision is made to expose the spinous processes. By advancing the introducer needle, the spinal catheter is inserted inside the thecal sac of the spinal canal while leaving the bone structures of the spine intact. This method allows continuous infusion into or sampling from the porcine thecal sac with minimal bleeding or CSF leakage. The procedure is simple, time-efficient, and reproducible across different experimental setups, offering significant potential for various pre-clinical studies, including pharmacokinetic research, surgical training, and spinal cord injury models.</p>","PeriodicalId":48787,"journal":{"name":"Jove-Journal of Visualized Experiments","volume":" 216","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143651539","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Electroporation-Based CRISPR-Cas9-Mediated Gene Knockout in THP-1 Cells and Single-Cell Clone Isolation.","authors":"Mathieu Pinaud, Alessia Zamborlini","doi":"10.3791/67469","DOIUrl":"https://doi.org/10.3791/67469","url":null,"abstract":"<p><p>The human acute monocytic leukemia (AML) THP-1 cell line is widely used as a model to study the functions of human monocyte-derived macrophages, including their interplay with significant human pathogens such as the human immunodeficiency virus (HIV). Compared to other immortalized cell lines of myeloid origin, THP-1 cells retain many intact inflammatory signaling pathways and display phenotypic characteristics that more closely resemble those of primary monocytes, including the ability to differentiate into macrophages when treated with phorbol-12-myristate 13-acetate (PMA). The use of CRISPR-Cas9 technology to engineer THP-1 cells through targeted gene knockout (KO) provides a powerful approach to better characterize immune-related mechanisms, including virus-host interactions. This article describes a protocol for efficient CRISPR-Cas9-based engineering using electroporation to deliver pre-assembled Cas9:sgRNA ribonucleoproteins into the cell nucleus. Using multiple sgRNAs targeting the same locus at slightly different positions results in the deletion of large DNA fragments, thereby increasing editing efficiency, as assessed by the T7 endonuclease I assay. CRISPR-Cas9-mediated editing at the genetic level was validated by Sanger sequencing followed by Inference of CRISPR Edits (ICE) analysis. Protein depletion was confirmed by immunoblotting coupled with a functional assay. Using this protocol, up to 100% indels in the targeted locus and a decrease of over 95% in protein expression were achieved. The high editing efficiency makes it convenient to isolate single-cell clones by limiting dilution.</p>","PeriodicalId":48787,"journal":{"name":"Jove-Journal of Visualized Experiments","volume":" 216","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143651482","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Implantation of Electroencephalogram and Electrocardiogram Telemetry Devices in Neonatal Rabbit Kits.","authors":"Julie Ziobro, Dalis Collins, Chunling Chen, Yan Chen, Luis F Lopez-Santiago, Gail Rising, Amber Yanovich, Jack M Parent, Lori L Isom","doi":"10.3791/67740","DOIUrl":"10.3791/67740","url":null,"abstract":"<p><p>Pathogenic variants in ion channel genes are associated with a high rate of sudden unexpected death in epilepsy (SUDEP). Mechanisms of SUDEP are poorly understood but may involve autonomic dysfunction and cardiac arrhythmias in addition to seizures. Some ion-channel genes are expressed in both the brain and the heart, potentially increasing the risk of SUDEP in patients with ion-channelopathies associated with epilepsy and cardiac arrhythmias. Transgenic rabbits expressing epilepsy variants provide a whole organism to study the complex physiology of SUDEP. Importantly, rabbits more closely replicate human cardiac physiology than do mouse models. However, rabbit models have additional health and anesthesia considerations when undergoing invasive monitoring procedures. We have developed a novel method to surgically implant a telemetry device for long-term simultaneous electroencephalogram (EEG) and electrocardiogram (ECG) monitoring in neonatal rabbit kits. Here, we demonstrate surgical methods to implant a telemetry device in P14 (weight range 175-250 g) kits with detailed attention to surgical approach, appropriate anesthesia and monitoring, and postoperative care, resulting in a low complication rate. This method allows for continuous monitoring of neural and cardiac electrophysiology during critical points in the development of cardiac arrhythmias, seizures, and potential SUDEP in rabbit models of genetic or acquired epilepsies.</p>","PeriodicalId":48787,"journal":{"name":"Jove-Journal of Visualized Experiments","volume":" 216","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143651491","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimizing Extracellular Vesicle Delivery Using a Core-Sheath 3D-Bioprinted Scaffold for Chronic Wound Management.","authors":"Saeid Vakilian, Fatemeh Jamshidi-Adegani, Fahad Al-Fahdi, Juhaina Al-Kindi, Ahmed Al-Harrasi, Sulaiman Al-Hashmi","doi":"10.3791/67764","DOIUrl":"https://doi.org/10.3791/67764","url":null,"abstract":"<p><p>This study outlines a detailed protocol for the fabrication of core-sheath 3D-bioprinted scaffolds designed to enhance chronic wound healing. The protocol involves isolating extracellular vesicles (EVs) from mesenchymal stem cells (MSCs), known for their regenerative and immunomodulatory properties. These EVs are then incorporated into a unique scaffold structure. The scaffold features a core composed of alginate loaded with EVs, surrounded by a sheath made of carboxymethyl cellulose and alginate lyase. This innovative design ensures controlled scaffold degradation while promoting efficient and controlled release of EVs at the wound site. The protocol covers key steps, including the preparation and characterization of the EVs, the formulation of bio-inks for 3D bioprinting, and the optimization of printing parameters to achieve the desired core-sheath architecture. By combining structural integrity and bioactivity, the scaffold aims to address the limitations of conventional wound dressings, offering a targeted approach to accelerate tissue regeneration and reduce inflammation in chronic wounds. This method provides a reproducible and scalable strategy for developing advanced biomaterials with potential clinical applications in chronic wound management. The protocol also highlights critical considerations for achieving consistent results, ensuring adaptability for future therapeutic applications.</p>","PeriodicalId":48787,"journal":{"name":"Jove-Journal of Visualized Experiments","volume":" 216","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143651583","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Clinical Application of Artificial Intelligence Preoperative Planning System Combined with Expert Database Retrieval in Complex Revision Hip Surgery.","authors":"Pei Liu, Guojie Liu, Xiaolu Xi, Ke Yuan, Qiang Xie, Peijian Tong, Yongqiang Sun","doi":"10.3791/68063","DOIUrl":"https://doi.org/10.3791/68063","url":null,"abstract":"<p><p>Accurate preoperative planning in revision hip arthroplasty is crucial for achieving successful outcomes. To enhance the intuitive evaluation of acetabular bone defect severity and leverage previous successful experience in revision hip arthroplasty, this study proposes a novel approach based on expert surgical case database retrieval and is initially implemented in clinical application. In this study, five patients who required revision hip arthroplasty were preoperatively planned to employ the expert case database surgical planning system.The patient's imaging data was entered into the system and matched with cases in the expert case database. Based on the expert's surgical experience, a revision surgery plan was recommended. If no suitable case was found, the model and position of the prosthesis were planned based on patient-specific reconstruction results. A total of five patients were enrolled in this study, four males and one female, with a mean age of 50.6 years. The diagnosis was aseptic prosthesis loosening after hip arthroplasty. The mean operative time was 123.2 min, and the mean intraoperative hemorrhage was 672 mL. No intraoperative complications, such as vascular or nerve injury, were observed. In Case 2, for instance, the application of this innovative planning scheme enabled the surgeon to delineate the revision surgery plan for this patient in the preoperative period, thereby reducing the operative time and intraoperative hemorrhage. Furthermore, patients could be apprised of the outcomes of analogous cases in advance. Leveraging a big data analysis approach through our comprehensive case database enables automated identification of matching expert treatment plans throughout the entire process. This particularly benefits inexperienced orthopedic surgeons by providing accurate guidance on surgical strategies to assist them in selecting appropriate prosthetic sizes and mounting positions. Additionally, the matching results can offer patients visualizations depicting predicted postoperative outcomes.</p>","PeriodicalId":48787,"journal":{"name":"Jove-Journal of Visualized Experiments","volume":" 216","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143651459","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Robotic-based Experimental Procedure for Colorimetric Gas Sensing Development.","authors":"Zechen Li, Siyuan Xu, Mengyang Cui, Jie Deng, Jing Jiang, Yijian Shi","doi":"10.3791/67940","DOIUrl":"https://doi.org/10.3791/67940","url":null,"abstract":"<p><p>This paper presents a robot-based experimental program aimed at developing an efficient and fast colorimetric gas sensor. The program employs an automated Design-Build-Test-learning (DBTL) approach, which optimizes the search process iteratively while optimizing multiple recipes for different concentration intervals of the gas. In each iteration, the algorithm generates a batch of recipe suggestions based on various acquisition functions, and with the increase in the number of iterations, the values of weighted objective function for each concentration interval significantly improve. The DBTL method begins with parameter initialization, setting up the hardware and software environment. Baseline tests establish performance standards. Subsequently, the DBTL method designs the following round of optimization based on the proportion of recipes in each round and tests performance iteratively. Performance evaluation compares baseline data to assess the effectiveness of the DBTL method. If the performance improvement does not meet expectations, the method will be performed iteratively; if the objectives are achieved, the experiment concludes. The entire process maximizes system performance through the DBTL iterative optimization process. Compared to the traditional manual developing process, the DBTL method adopted by this experimental process uses multi-objective optimization and various machine learning algorithms. After defining the upper and lower limits of component volume, the DBTL method dynamically optimizes iterative experiments to obtain the optimal ratio with the best performance. This method greatly improves efficiency, reduces costs, and performs more efficiently within the multi-formulation variable space when finding the optimal recipe.</p>","PeriodicalId":48787,"journal":{"name":"Jove-Journal of Visualized Experiments","volume":" 216","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143651535","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Screening and Isolation of C-Glycoside-Cleaving Intestinal Bacteria.","authors":"Lan Yang, Yudi Nie, Wenchao Shen, Wenfu Ma, Rufeng Wang","doi":"10.3791/67346","DOIUrl":"https://doi.org/10.3791/67346","url":null,"abstract":"<p><p>C-glycosides are commonly found in medicinal plants and exhibit extensive structural diversity along with various bioactivities, including antibacterial, anti-inflammatory, antiviral, antioxidant, and antineoplastic activities. In C-glycosides, the anomeric carbon of the sugar moiety is directly connected to an aglycone through carbon-carbon bonding. Compared with O-glycosides, C-glycosides are structurally stable and resistant to acids and enzymes. Consequently, they are typically unbreakable, resulting in poor absorbability and low bioavailability. Interestingly, some intestinal bacteria can cleave C-C glycosidic bonds, providing a specific and environmentally friendly biological approach to degrade C-glycosides. In this study, a set of standard operating procedures (SOPs) was developed for screening intestinal bacteria capable of cleaving C-C glycosidic bonds based on the biotransformation model of natural compounds. The SOPs include the preparation and enrichment of intestinal bacteria, activity-oriented screening, and activity validation in a low-carbon source medium. This methodology provides a foundational reference for researchers aiming to isolate and study these specialized functional bacteria.</p>","PeriodicalId":48787,"journal":{"name":"Jove-Journal of Visualized Experiments","volume":" 216","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143651537","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Preclinical Model of Prenatal Delta-9-Tetrahydrocannabinol Exposure to Assess Its Impact on Neurodevelopmental Outcomes.","authors":"Suzy Davies, Zarena M Dominguez, Jessie R Maxwell","doi":"10.3791/68119","DOIUrl":"https://doi.org/10.3791/68119","url":null,"abstract":"<p><p>Prenatal cannabinoid exposure (PCE) is becoming increasingly frequent as more states across the United States legalize recreational marijuana (cannabinoids). The consumption of cannabinoid products during pregnancy has been associated with various abnormal outcomes, although historical studies were conducted during a time when the potency of these products was approximately 300% lower than that of current products. Given the rising use of cannabinoids, it is essential to understand the potential impacts PCE may have on fetal neurodevelopment and subsequent infant and child development. Previous studies have demonstrated that PCE negatively affects learning and memory, behavioral skills, sleep, and attention in offspring. The aim of this study is to recapitulate PCE through voluntary ingestion of delta-9-tetrahydrocannabinol (THC), the psychoactive component of cannabinoid products, during pregnancy in a preclinical model. This article outlines the procedure for achieving moderate PCE throughout gestation. In this model, the control group consumes plain mini-chocolate/peanut butter cookies, while the PCE group consumes THC mixed into peanut butter paired with mini-chocolate cookies. This approach enables further investigation into the impact of PCE on developmental outcomes.</p>","PeriodicalId":48787,"journal":{"name":"Jove-Journal of Visualized Experiments","volume":" 216","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143651584","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Preparation and Maintenance of Bioexclusion IsoPositive Cage Experiment for Human Fecal Transplantation into Germ-Free Mice.","authors":"Rachel C Newsome, Chancellor McGriff, Raad Z Gharaibeh, Christian Jobin","doi":"10.3791/68029","DOIUrl":"https://doi.org/10.3791/68029","url":null,"abstract":"<p><p>Germ-free mice are an important investigation tool for understanding the contribution of microorganisms in host health and disease, enabling assessment of the specific role of individuals, defined or complex groups of microorganisms in host response. Traditionally bred and reared in flexible-film or semi-rigid isolators, germ-free mouse husbandry and experimental manipulation are costly and require numerous trained staff and a large space footprint in animal housing facilities. The IsoPositive caging system allows for experimental manipulation of germ-free mice in individual, hermetically-sealed, positive-pressure isolator cages (isocages), reducing cost and enabling greater flexibility in experimental manipulations. Here, a protocol is described for transferring germ-free mice from breeding isolators to isocages and subsequent fecal transfer from human donor stool into mice to create stable long-term gut \"humanized\" mice for future studies. The materials and preparation needed for the utilization of the isocage system are described, including the use of chlorine-dioxide sterilant chemical sterilant to clean cages, supplies, equipment, and personal protective equipment. The methods for confirming the germ-free status of transferred mice and how to determine contamination in the caging system are discussed. The procedure for husbandry, including bedding, food, and water supply, is further discussed. The protocol for human fecal slurry preparation and gavage into germ-free mice to create gut \"humanized\" mice, along with stool collection to monitor the microbial community composition of these mice, are described. An experiment illustrates that two weeks post-human fecal transplant allows for stable colonization of donor microbiota in the murine hosts, enabling subsequent experimental usage. Furthermore, the collection of humanized mouse feces in viability preservation media, enabling use in further functional experiments, is described. Overall, these methods allow for the safe and effective establishment of humanized mouse communities in experimental gnotobiotic cages for further manipulation.</p>","PeriodicalId":48787,"journal":{"name":"Jove-Journal of Visualized Experiments","volume":" 216","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143651586","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Covalent Fragment Screening Using the Quantitative Irreversible Tethering Assay.","authors":"Charles P Brown, Alan Armstrong, David J Mann","doi":"10.3791/67178","DOIUrl":"https://doi.org/10.3791/67178","url":null,"abstract":"<p><p>Compounds that form covalent bonds with specific target proteins offer a variety of advantages as chemical probes and therapeutic agents. Most commonly, mildly reactive, electrophilic small molecules are employed to form covalent bonds with select cysteine side chains in specific proteins. Electrophile-first approaches of ligand discovery, whereby a library of electrophilic small molecules are screened against a protein target, have become popular as they avoid the need for time-consuming downstream installation of an electrophilic warhead. Such screening is complicated, however, as electrophilic ligands can exhibit a wide range of different rates of spontaneous reaction with cysteines. Quantitative-irreversible tethering (qIT) offers a fluorescence-based method for hit identification and development that normalizes data for these differences in intrinsic compound reactivity. Rates of reaction of individual compounds with a target protein are determined and compared to compound reactivity with the unstructured tripeptide glutathione (this being a proxy for spontaneous compound reaction), enabling the identification of compounds that preferentially react with the protein of interest. This methodology has been successfully applied to identify selective covalent fragments against several drug targets, including SARS-CoV-2 main protease, cyclin-dependent kinase 2, and RAP27A. Here, we demonstrate the application of qIT to a target protein to generate a quantitative and robust data set, allowing prioritization of hit ligands for future development.</p>","PeriodicalId":48787,"journal":{"name":"Jove-Journal of Visualized Experiments","volume":" 216","pages":""},"PeriodicalIF":1.2,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143651464","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"综合性期刊","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}