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Childhood Malignancies, Cysts, and Sinuses of the Head and Neck
Published in R James A England, Eamon Shamil, Rajeev Mathew, Manohar Bance, Pavol Surda, Jemy Jose, Omar Hilmi, Adam J Donne, Scott-Brown's Essential Otorhinolaryngology, 2022
Chordoma is a rare, slow-growing, bony tumour from embryonic remnants of notochord. In head and neck, chordoma is most often found in the nasopharynx and skull base, and it is locally aggressive. Rarely is completely excisable, so post-operative radiotherapy is used, but proton-beam therapy is increasingly used.
Developmental Diseases of the Nervous System
Published in Philip B. Gorelick, Fernando D. Testai, Graeme J. Hankey, Joanna M. Wardlaw, Hankey's Clinical Neurology, 2020
James H. Tonsgard, Nikolas Mata-Machado
Anomalies of gastrulation/disorders of notochord development: Neurenteric cysts.Split spinal cord malformations (SSCM; diastematomyelia).Dermal sinus.
Congenital Anomalies
Published in Swati Goyal, Neuroradiology, 2020
The spinal cord is developed in three main stages − gastrulation, primary neurulation, and secondary neurulation during early embryogenesis. Gastrulation (second or third week) − conversion of the embryonic bilaminar disk to a trilaminar disk, composed of the ectoderm, the mesoderm, and the endoderm. The notochord is formed from the midline mesoderm interacting with the overlying ectoderm.Primary neurulation (third or fourth week) − formation of the neural plate and eventually the closure of the neural tube in a zip-like manner.Secondary neurulation (fifth or sixth week) − formation of the central canal (canalization), with the caudal cell mass undergoing retrogressive differentiation to form the conus medullaris, filum terminale, ventriculus terminalis, and most of the sacrum and coccyx.
Focal Pachymeningitis Induced Papilloedema as an Early Manifestation of Relapsing Polychondritis
Published in Neuro-Ophthalmology, 2023
Majda Rachdi, Abraham J. Beun, Stelianos Kampouridis, François Willermain, Tom Buelens
The exact aetiology of RPC remains currently unknown, but it is considered to involve genetic predisposition and both the humoral and cell-mediated immune systems.1,17 One study that examined the immunogenetics of RPC identified human leukocyte antigen (HLA)-DR4 as the major risk allele for RPC.18 In addition to genetic susceptibility, circulating antibodies against several types of collagen (mainly collagens II, IX, and XI) have been detected, as well as against other cartilage proteins, such as cartilage matrix protein (or matrilin-1) and cartilage oligomeric matrix proteins.1,17,19 Up to one-third of patients with RPC present with other autoimmune disease, whether this association with other diseases is purely coincidental or representative of a shared genetic predisposition is currently unknown.16,19 Nervous system involvement is uncommon, especially at disease onset, and may be related to vasculitis20 or meningoencephalitis.21,22 It has also been speculated that remnants of the notochord could serve as antigens, or that the central nervous system may contain an antigen distinct from collagen.23
SDH5 down-regulation mitigates the damage of osteoporosis via inhibiting the MyD88/NF-κB signaling pathway
Published in Immunopharmacology and Immunotoxicology, 2023
Hongzi Wu, Dehua Zhang, Haijun Xia, Yongqi Li, Feng Mao, Yi Liao
Histological analysis was conducted to further evaluate the function of SDH5 knockdown on osteoporosis rats. In the Sham group, the nucleus pulposus was hydrated, the cartilage was smooth and there was an extracellular matrix around it. However, nucleus pulposus atrophy, cluster formation, and cleft formation were put into an observation in the OVX group. This abnormal histological phenomenon was restored by the knockdown of SDH5. The nucleus pulposus shows a normal number of notochord cells and slight mucoid degeneration (Figure 3(A)). As indicated in Figure 3(B), the percentage of cartilage area was dramatically decreased in OVX group compared with the Sham group. Notably, this trend could be reverse by SDH5 knockdown. Moreover, Western blot showed that the expression of bone remodeling-associated cytokines, such as Osx, CoL1A1, and OC, were markedly enhanced by suppressing SDH5 in osteoporosis rats. Moreover, IHC was performed to determine the presentation of Osx, RUNX2, and OC in the tibia tissues of rats. After silencing of SDH5, the expression of RUNX2, Osx, and OC was obviously increased in OVX rats (Supporting Information Figure S1). Taken together, SDH5 knockdown could ameliorate OVX-induced cartilage damage in vivo.
Intervertebral Disc Degeneration Models for Pathophysiology and Regenerative Therapy -Benefits and Limitations
Published in Journal of Investigative Surgery, 2022
Yidian Wang, Jihe Kang, Xudong Guo, Daxue Zhu, Mingqiang Liu, Liang Yang, Guangzhi Zhang, Xuewen Kang
Unlike cells of the AF and CEP, which remain relatively stable throughout life, cells in the NP undergo dramatic changes within the first decade of human growth and development. Humans, bovine, ovine, horses and chondrodystrophoid dogs(CD)are born with a progressive reduction of vacuolated notochordal cells (NCs), which gradually differentiate into chondroid cells and disappear before adulthood. However, pigs, rabbits, nonchondrodystrophoid dogs (NCD), mice, and rats maintain a constant number of NCs until adulthood [41–44](Figure 2 illustrates the time course of NPCs isolated from rat tail IVD in vitro). Currently, several studies have found that incubation of notochordal cell conditioned medium (NCCM) and partially digested NCs enriched nucleus pulposus tissue with NPCs upregulates the expression of extracellular matrix (ECM), enhances cell viability, and inhibits stress-induced apoptosis [45–47]. In addition, the use of mesenchymal stem cells (MSCs), a type of pluripotent stem cells, holds great promise in the field of IVD regeneration [48–51], and soluble factors secreted by NCs can similarly promote the expression of PGs and COL2 in MSCs and reduce cell senescence [52]. These results suggest that NCs have a potential role in delaying IDD, and the disappearance of NCs in adults is likely to be directly related to IDD. Therefore, the potential effects of NCs should be considered in both in vivo and in vitro models, and results obtained from animals that retain NCs in adulthood may not be related to human IDD.