Efficient and sustained FOXP3 locus editing in hematopoietic stem cells as a therapeutic approach for IPEX syndrome.

Immune dysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX) syndrome is a monogenic disorder caused by mutations in the FOXP3 gene, required for generation of regulatory T (Treg) cells. Loss of Treg cells leads to immune dysregulation characterized by multi-organ autoimmunity and early mortality. Hematopoietic stem cell (HSC) transplantation can be curative, but success is limited by autoimmune complications, donor availability and/or graft-vs.-host disease. Correction of FOXP3 in autologous HSC utilizing a homology-directed repair (HDR)-based platform may provide a safer alternative therapy. Here, we demonstrate efficient editing of FOXP3 utilizing co-delivery of Cas9 ribonucleoprotein complexes and adeno-associated viral vectors to achieve HDR rates of >40% in vitro using mobilized CD34+ cells from multiple donors. Using this approach to deliver either a GFP or a FOXP3 cDNA donor cassette, we demonstrate sustained bone marrow engraftment of approximately 10% of HDR-edited cells in immune-deficient recipient mice at 16 weeks post-transplant. Further, we show targeted integration of FOXP3 cDNA in CD34+ cells from an IPEX patient and expression of the introduced FOXP3 transcript in gene-edited primary T cells from both healthy individuals and IPEX patients. Our combined findings suggest that refinement of this approach is likely to provide future clinical benefit in IPEX.

A novel anatomo-physiologic high-grade spondylolisthesis model to evaluate L5 nerve stretch injury after spondylolisthesis reduction.

L5 nerve palsy is a well-known complication following reduction of high-grade spondylolisthesis. While several mechanisms for its occurrence have been proposed, the hypothesis of L5 nerve root strain or displacement secondary to mechanical reduction remains poorly studied. The aim of this cadaveric study is to determine changes in morphologic parameters of the L5 nerve root during simulated intraoperative reduction of high-grade spondylolisthesis. A standard posterior approach to the lumbosacral junction was performed in eight fresh-frozen cadavers with lumbosacral or lumbopelvic screw fixation. Wide decompressions of the spinal canal and L5 nerve roots with complete facetectomies were accomplished with full exposure of the L5 nerve roots. A 100% translational slip was provoked by release of the iliolumbar ligaments and cutting the disc with the attached anterior longitudinal ligament. To evaluate the path of the L5 nerves during reduction maneuvers, metal bars were inserted bilaterally at the inferomedial aspects of the L5 pedicle at a distance of 10 mm from the midpoint of the L5 pedicle screws. There was no measurable change in length of the L5 nerve roots after 50% and 100% reduction of spondylolisthesis. Mechanical strain or displacement during reduction is an unlikely cause of L5 nerve root injury. Further anatomical or physiological studies are necessary to explore alternative mechanisms of L5 nerve palsy in the setting of high-grade spondylolisthesis correction, and surgeons should favor extensive surgical decompression of the L5 nerve roots when feasible.

Split Azygos Vein: A Case Report.

The azygos venous system, which comprises the azygos, hemiazygos, and accessory hemiazygos veins, assists in blood drainage into the superior vena cava (SVC) from the thoracic cage and portions of the posterior mediastinum. Routine dissection of a fresh-frozen cadaveric specimen revealed a split azygos vein. The azygos vein branched off the inferior vena cava (IVC) at the level of the second lumbar vertebra as a single trunk and then split into two tributaries after forming a venous plexus. The right side of this system drained into the SVC and, inferiorly, the collective system drained into the IVC. Variant forms in the venous system, especially the vena cavae, are prone to dilation and tortuosity, leading to an increased likelihood of injury. Knowledge of the anatomical variations of the azygos vein is important for surgeons who use an anterior approach to the spine for diverse procedures.

Update on the Biomechanics of the Craniocervical Junction-Part I: Transverse Atlantal Ligament in the Elderly.

STUDY DESIGN: In vitro biomechanical study. OBJECTIVE: The transverse ligament is the strongest ligament of the craniocervical junction and plays a critical role in atlanto-axial stability. The goal of this cadaveric study, and the subsequent study (part II), was to reevaluate the force required for the transverse ligament and alar ligament to fail in a more physiological biomechanical model in elderly specimens. METHODS: Twelve C1-2 specimens were harvested from fresh-frozen Caucasian cadavers with a mean age at death of 81 years (range 68-89 years). Only the transverse ligament was preserved, and the bony C1-2 complex was left intact. The dens was pulled away from the anterior arch of C1 using a strength test machine that applies controlled increasing force. After testing, the axis was split in half to check for hidden pathologies and osteoporosis. The differences in the failure force between sex and age groups (group 1: <80 years, group 2: >80 years) were compared. RESULTS: The mean force required for the transverse ligament to fail was 236.2 ± 66 N (range 132-326 N). All but 2 specimens had significant osteoporotic loss of trabecular bone. No significant differences between sex and age groups were found. CONCLUSIONS: The transverse ligament's failure in elderly specimens occurred at an average force of 236 N, which was lower than that reported in the previous literature. The ligament's failure force in younger patients differs and may be similar to the findings published to date.

The effects of obesity on the human body, part I: Skin and musculoskeletal.

Obesity is a worldwide issue that many global health authorities consider a growing epidemic. Having a positive correlation between increases in the industrialization of processed foods and sedentary occupations as well as a lack of access to healthcare in poorer socioeconomic areas, obesity is a multifactorial disease affecting several organ systems. The tendency for obesity to cause detrimental changes to the human body is a focal point for healthcare providers to establish more effective clinical treatment and management plans. Implementing comprehensive global educational programs to decrease the prevalence of this unforgiving disease is imperative for a healthier future. Herein, we have provided a comprehensive review of the health effects of obesity upon the human body for the interest of many practicing clinicians managing this health crisis.

The effects of obesity on the human body part II: Nervous, respiratory, and lymphatic systems.

This second installment of The Effects of Obesity on the Human Body considers the nervous, respiratory, and lymphatic systems. Those with obesity face countless psychological hurdles in addition to the respiratory burden and widespread inflammation that can suppress the immune system, resulting in the accumulation of excess fluid in body tissues.

Update on the Biomechanics of the Craniocervical Junction, Part II: Alar Ligament.

STUDY DESIGN: In vitro biomechanical study. OBJECTIVE: The strength of the alar ligament has been described inconsistently, possibly because of the nonphysiological biomechanical testing models, and the inability to test the ligament with both attachments simultaneously. The purpose of this biomechanical model was to reevaluate the alar ligament's tensile strength with both bony attachments, while also keeping the transverse ligament intact, all in a more physiological biomechanical model that mimics the mechanism of traumatic injury closely. METHODS: Eleven fresh-frozen occipito-atlanto-axial (C0-C1-C2) specimens were harvested from individuals whose mean age at death was 77.4 years (range 46-97 years). Only the alar and transverse ligaments were preserved, and the bony C0-C1-C2 complex was left intact. Axial tension was exerted on the dens to displace it posteriorly, while the occipito-axial complex was fixed anteriorly. A device that applies controlled increasing force was used to test the tensile strength (M2-200, Mark-10 Corporation). RESULTS: The mean force required for the alar ligament to fail was 394 ± 52 N (range 317-503 N). However, both the right and left alar ligaments ruptured simultaneously in 10 specimens. The ligament failed most often at the dens (n = 10), followed by occipital condyle rupture (n = 1). The transverse ligament remained intact in all specimens. CONCLUSIONS: When both the right and left alar ligament were included, the total alar ligament failure occurred at an average force of 394 N. The alar ligament failed before the transverse ligament.

The effects of obesity on the human body part III: Cardiovascular, digestive, excretory, endocrine, and reproductive.

This third installment of The Effects of Obesity on the Human Body discusses the endocrine, digestive, reproductive, cardiovascular, and excretory systems. Obesity is known to upset hormonal balance, leading to widespread metabolic disorders involving organs such as the liver and pancreas. Furthermore, the hypersecretion of leptin from adipose tissue triggers various responses from the cardiovascular and gastrointestinal systems, with implications for energy and nutrient balance and uptake.

The Diploic Veins: A Comprehensive Review with Clinical Applications.

The diploic veins serve as an important connection between the extracranial and intracranial venous systems. They change in size during growth from adolescence to adulthood. The diploic space has been identified as an additional site of reabsorption of cerebrospinal fluid (CSF). Herein, the anatomy and physiology of the diploic veins are reviewed.

The carotid body and associated tumors: updated review with clinical/surgical significance.

Purpose: The carotid body functions as a chemoreceptor and receives richer blood supply, by weight, than any other organ in the body. We review the literature regarding the anatomy, histology, and function of the carotid body and the incidence, functionality, and clinical relevance of carotid body tumors and paragangliomas. These lesions are often nonfunctional but can be associated with catecholamine secretion. Most patients are asymptomatic or present initially with a cervical mass. As the tumors grow, they can impinge on nearby cranial nerves. Although there is some debate, the dominant clinical strategy is to surgically resect these tumors as early as possible. If they are resected early, the risk of postoperative neurovascular injury is minimized. Methods: Literature search was performed using the PubMed database with focus on articles including descriptions of the carotid body and associated tumors. Results: We reviewed recent literature that related to the anatomy of the carotid body while also including carotid pargangliomas and associated diagnosis with treatment interventions. Conclusion: As the carotid body serves as a vital modulator of cardiovascular and respiratory functions, illustrates the importance of identifying potential carotid paragangliomas due its ability to impede function of the carotid body. By understanding carotid paraganglioma's distinct etiologies while also understanding proper diagnosis of tumors allows for early detection and appropriate treatment options.

Clinical anatomy of the maxillary sinus: application to sinus floor augmentation.

The anatomy of the maxillary sinus, especially its vascular anatomy, and its relationships with the teeth and alveolar processes have been well documented. The development of cone-beam computed tomography has resulted in dentists being more familiar with maxillary sinus floor augmentation procedures. This paper aims to revisit the classic anatomy of the maxillary sinus and review the newly published literature in order to help dentists diagnose in more detail and perform safer surgery of the maxillary sinus.

An elongated dorsally curved xiphoid process.

The xiphoid process of the sternum lies in the epigastric region and functions to serve as an attachment point for vital muscles that aid in respiration. With the xiphoid process extending as the most inferior portion of the sternum, variable morphology is widely observed. During a routine dissection of a 44-year-old Caucasian male cadaver, we discovered a hook-shaped, elongated xiphoid process that protruded dorsally. Potential clinical significance can arise leading to misdiagnosis of the hook-shaped xiphoid process as an epigastric mass during imaging. Though various variations of xiphoid process have been well documented, knowledge of a hook-shaped xiphoid process orientated dorsally remains scarce. Herein, this case study provides clinicians, surgeons, and radiologists a rare anomaly of the xiphoid process in order to further the knowledge of morphological variations of the xiphoid to prevent misdiagnosis and surgical complications.

Sudden Headache and Blindness Due to Pituitary (Adenoma) Infarction: A Case Report.

Pituitary infarction (PI) is a rare medical emergency appearing in patients with pituitary adenoma, presenting with sudden onset of severe headache, and often associated with vomiting, nausea, visual deterioration, and decreased consciousness. We describe an 83-year-old woman who presented with blindness after a history of severe headache. An urgent computed tomography (CT) scan of the brain had been arranged, and a massive pituitary adenoma with hemorrhage was observed, and admission to the neurosurgical department followed. A multidisciplinary team comprising a neurosurgeon, an ophthalmologist, and an endocrinologist is required to manage such cases. To confirm the diagnosis, an urgent magnetic resonance imaging (MRI) must be performed; CT scan can be indicated if MRI is contraindicated or not possible.

Neck movement during cervical transforaminal epidural injections and the position of the vertebral artery: an anatomical study.

BACKGROUND: Cervical transforaminal epidural steroid injections (CTFESIs) are sometimes performed in patients with cervical radiculopathy secondary to nerve-root compression. Neck movements for patient positioning may include rotation, flexion, and extension. As physicians performing such procedures do not move the neck for fear of injuring the vertebral artery, we performed fluoroscopy and cadaveric dissection to analyze any movement of the vertebral artery during head movement and its relation to the foramina in the setting of CTFESI. PURPOSE: To determine cervical rotational positioning for optimized vertebral artery location in the setting of cervical transforaminal epidural steroid injections. MATERIAL AND METHODS: Four sides from two Caucasian whole cadavers (all fresh-frozen) were used. Using a guide wire and digital subtraction fluoroscopy, we evaluated the vertebral artery mimicking a CTFESI, then we removed the transverse processes and evaluated the vertebral artery by direct observation. RESULTS: After performing such maneuvers, no displacement of the vertebral artery was seen throughout its course from the C6 to the C2 intervertebral foramina. To our knowledge, this is the first anatomical observation of its kind that evaluates the position of the vertebral artery inside the foramina during movement of the neck. CONCLUSION: Special caution should be given to the medial border of the intervertebral foramina when adjusting the target site and needle penetration for the injection. This is especially true for C6-C4 levels, whereas for the remaining upper vertebrae, the attention should be focused on the anterior aspect of the foramen. Since our study was centered on the vertebral artery, we do not discard the need for contrast injection and real-time digital subtraction fluoroscopy while performing the transforaminal epidural injection in order to prevent other vascular injuries.

The Carotid Sinus Nerve and the First English Translation of Hering's Original Research on this Nerve.

This paper provides a brief depiction of the life and achievements of the most iconic experiments of Heinrich Ewald Hering. The authors herein have presented a translation of his paper on the carotid sinus nerve in English; the original paper by Heinrich Ewald Hering, titled "Ueber die Wand des Sinus caroticus als Reizempfänger und den Sinusnerv als zentripetale Bahn für die Sinusreflexe" (1924), provides a detailed account of his experimental process and findings. He recognized that the sinus reflexes are mediated by a branch of the glossopharyngeal nerve (CN IX).

The condylar canal and emissary vein-a comprehensive and pictorial review of its anatomy and variation.

The condylar canal and its associated emissary vein serve as vital landmarks during surgical interventions involving skull base surgery. The condylar canal serves to function as a bridge of communication from the intracranial to extracranial space. Variations of the condylar canal are extremely prevalent and can present as either bilateral, unilateral, or completely absent. Anatomical variations of the condylar canal pose as a potential risk to surgeons and radiologist during diagnosis as it could be misinterpreted for a glomus jugular tumor and require surgical intervention when one is not needed. Few literature reviews have articulated the condylar canal and its associated emissary vein through extensive imaging. This present paper aims to further the knowledge of anatomical variations and surgical anatomy involving the condylar canal through high-quality computed tomography (CT) images with cadaveric and dry bone specimens that have been injected with latex to highlight emissary veins arising from the condylar canal.

The Great Auricular Nerve: Anatomical Study with Application to Nerve Grafting Procedures.

BACKGROUND: When it comes to autogenous nerve grafting, the sural and great auricular nerve (GAN) are the 2 nerves predominately used for trigeminal and facial nerve repair. Arising from the second and third cervical ventral rami, the GAN emerges from the posterior border of the sternocleidomastoid coursing superiorly and anteriorly toward the ear. METHODS: Eleven sides from 5 Caucasian and 1 Asian cadaveric heads (all fresh-frozen) were used. One man and 5 women were used with an age at death ranging from 57 to 91 years, with a mean of 80.3 years. Measurements were made from the inferior border of the ear to the GAN, the GAN to the external jugular vein, and the inferior border of the mastoid process to the GAN; the proximal, medial, and distal diameters of the GAN and the length of the GAN that was obtained from this exposure were also measured. RESULTS: The mean distance from the inferior border of the mastoid process to the GAN, inferior border of the ear to the GAN, and GAN to the external jugular vein was 27.71, 31.03, and 13.28 mm, respectively. The mean length of the GAN was 74.86 mm. The mean diameter of its distal, middle, and proximal portions was 1.51, 1.38, and 1.58 mm, respectively. CONCLUSIONS: The GAN is an excellent option for use in nerve grafting for repair of, for example, facial dysfunction. In this study, we review our measurements, techniques for identification, and dissecting techniques for the GAN. The proximity to the operative area and minimal complications associated with GAN grafting might contribute to improved patient satisfaction and better outcomes regarding functional restoration.

A Median Artery of the Corpus Callosum.

The anterior communicating artery is one of the main components of the vascular network that delivers blood to the brain. Therefore, a good understanding of the normal anatomy and its variations is important to neurologists, neurosurgeons, and other health care providers dealing with the central nervous system. Here, we present a case of a median artery of the corpus callosum found in a cadaver, with consideration of cerebral hemodynamics implications.

Comprehensive Review of Spinal Neurenteric Cysts with a Focus on Histopathological Findings.

Among the occult spinal dysraphisms, neurenteric cysts (NECs) are rare and are thought to arise due to a failure of the separation of the primitive endoderm and ectoderm. Patients experience various neurological symptoms depending on the location of the lesion. As the epithelial morphology of NECs share similarities with other intracranial and intraspinal cystic growths, the definitive diagnosis of NEC can be made after a histochemical analysis with endodermal markers. Complete resection is associated with the lowest disease recurrence rate.

Bilateral sternocleidomastoid variant with six distinct insertions along the superior nuchal line.

Anatomical variations of the sternocleidomastoid muscle (SCM) have been observed to occupy multiple origins and insertion points and have supernumerary heads, sometimes varying in thickness. During routine dissection, a SCM was observed to have six distinct insertions that interface with the course of the superior nuchal line, ending at the midline, bilaterally. This variation was also seen to receive innervation from the accessory nerve as well as the great auricular nerve. To our knowledge, this variant of supernumerary insertions and nerve innervations has not yet been reported. These variants may pose as problematic during surgical approaches to the upper neck and occiput, and should thus be appreciated by the clinician. Herein we discuss the case report, possible embryological origins, and the clinical significance of the observed variant SCM.