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Micromorphology, microstructure and micro-Raman spectroscopy of a case of amelogenesis imperfecta
Published in J. Belinha, R.M. Natal Jorge, J.C. Reis Campos, Mário A.P. Vaz, João Manuel, R.S. Tavares, Biodental Engineering V, 2019
Sebastiana Arroyo Bote, Alfonso Villa-Vigil, M.C. Manzanares Céspedes, Esteban Brau-Aguadé
Amelogenesis Imperfecta (AI) is characterized by presenting enamel defects, without defects in others tissues (Witkop, 1988). Hereditary defects in the enamel development or environmental exposure to chemicals and drugs can damage the ameloblasts (Ferreira et al., 2005). AI is characterized by its heterogeneous phenotypical clinical patterns of variable severity, as well as for its complex genetype (Wright, 2006; Gibson, 2008; Wang et al., 2013) and/or environmental aetiology (Hedge, 2012; Malik et al., 2012). Based on its heredity and clinical evidences, four types and numerous subtypes of AI were described in 1988 by Witkop (hypoplastic, hypomaturation, hypocalcified AI and a combination of them), and today this is the most widely used classification in the clinical practice. The development of enamel starts with the secretion of the enamel protein matrix by the ameloblasts, followed by its calcification and maturation (Sapp et al., 2005; Malik et al., 2012). Less than 1% of the mature enamel is constituted by organic components, while the mineral components constitute more than a 95%. The enamel mineral crystals are deposited in compact hexagonal rod-shaped structure, making this tissue the hardest in the human body (Nanci, 2012). Numerous genes have been reported as responsible of the regulation of this complex process (Sapp et al., 2005; Bailleul-Forestier et al., 2008; Lee et al., 2008; Misiadis & Luder, 2011; Luder et al., 2013; Simmer et al., 2013; Wang et al., 2014; Zhang et al., 2015; Prasad et al., 2016). Mutations of AMELX (amelogenin), ENAM (enamelin) (Misiadis & Luder, 2011), COL17A1 (Prasad et al., 2016) and FAM20A (Wang et al., 2014) have been proven as causes of hypoplastic AI, either with smooth or rough enamel; while the AI with hypomature phenotype has been attributed to genetic defects in AMELX, MMP20, KLK4 and WDR72. Hypocalcified AI have been reported to be caused by FAM83H or C4orf26 (Kim et al., 2008; Parry et al., 2012; Luder et al., 2013) in humans. Additionally, some studies indicate that a mutation in one gene could be related to more than one type of AI; thus CNNM4 mutation is related to hypoplastic/hypomineralized types (Lee et al., 2008), DLX3 mutation is related with and hypomature/hypoplastic types (Wang et al., 2014) and C4orf26 hypomineralized-hypoplastic types (Prasad et al., 2016).
The peripheral blood transcriptome identifies dysregulation of inflammatory response genes in polycystic ovary syndrome
Published in Gynecological Endocrinology, 2018
Nian-Jun Su, Jian Ma, De-Feng Feng, Shuai Zhou, Zi-Tao Li, Wei-Ping Zhou, Hua Deng, Jia-Ying Liang, Xu-Hui Yang, Yue-Mei Zhang, Feng-Hua Liu, Liang Zhang
In the present analysis, several inflammatory molecules were proposed in PCOS. ORM1/2, orosomucoid 1/2, belongs to key acute-phase plasma proteins. Usually, it increases gene expression due to acute inflammation. Therefore, it is classified as an acute phase reactant. Recently, ORM1 and ORM2 mRNA expression levels were identified up-regulation in endometrium from patients with PCOS revealing inflammatory change compared with controls [18]. PROK2, prokineticin 2, is the human paralogue of PROK1. Strong expression of PROK1 has been reported in PCOS, indicating its involvement in this disease entity [19]. MMP25, matrix metallopeptidase (MMP) 25, also is named as MMP20. Proteins of the MMP family can degrade extracellular matrix in normal physiological processes including embryonic development and tissue remodeling, as well as in pathological processes such as PCOS [20,21]. Elevated serum concentrations of MMP2 and MMP9 were found in women with PCOS [22,23]. The dysregulation of MMP25 in PCOS and its pathological role warrant further research. S100A12, S100 calcium binding protein A12, belongs to the S100 family of proteins. RAGE, a receptor of S100A12, was found highly expressed in serum of PCOS patients [24]. Also, mounting evidence has shown that this gene is involved in inflammation and diabetes [25–27]. Taken together, up-regulation of S100A12 may play an important role in the development of PCOS.
Comprehensive analysis of matrix metalloproteinases and their inhibitors in head and neck squamous cell carcinoma
Published in Acta Oncologica, 2022
Mingyuan Zou, Chen Zhang, Yan Sun, Huina Wu, Feng Xiao, Wei Gao, Fengfeng Zhao, Xiaobo Fan, Guoqiu Wu
Next, survival analysis was performed to investigate the effect of MMP/TIMP expression on patient overall survival probability using KM curves. Patients were classified into high-expression and low-expression groups according to the median value of each mRNA. The survival curves of only five genes (MMP14, MMP20, MMP25, TIMP1, and TIMP4) showed significant differences between the high-expression and low-expression groups (Figure S3). The overall survival of patients with high expression of MMP14, MMP20, TIMP1, and TIMP4 was significantly worse than that of patients with low expression of these MMPs. However, the overall survival of patients with low expression of MMP25 was significantly worse than that of patients with low expression of MMP25.
Critical roles of adherens junctions in diseases of the oral mucosa
Published in Tissue Barriers, 2023
Christina Kingsley, Antonis Kourtidis
Ameloblasts are the precursor cells that form enamel, the rigid, outermost surface of the tooth (Box 1). These cells progress through stages that require intercellular contact and communication. AJs are required in order for these cells to fully differentiate. It was demonstrated that the Rho-associated coiled-coil-containing protein kinase (ROCK) regulates ameloblast differentiation as well as enamel production. Inhibition of ROCK hindered polarization of differentiated ameloblasts, as well as formation of the terminal band structure of actin and E-cadherin.107 Furthermore, it was found that mice without nectin-1 exhibited defective enamel formation.108 The integral membrane proteins of ameloblast AJs are E-cadherin and N-cadherin. Also found in these junctions are associated proteins, which include α-catenin, β-catenin, p120, vinculin, actin, and myosin.109,110 One integral protein to this process is MMP20. MMP20 cleaves the extracellular domains of E- and N-cadherin, facilitating ameloblast organization.111 During the secretory stage of enamel formation, AJs are necessary for the attachment-detachment process that allows the pattern of the enamel to form. Indeed, p120 knockout in a mouse model adversely affects dental enamel development, since p120 plays a role directing the attachment and detachment of the secretory stage ameloblasts as they move in rows.112 Mutations in the AJ proteins nectin-1 and nectin-3 also result in enamel defects, such as a hinderance of mineralization and abnormal tooth shape, further denoting the critical involvement of AJ components in enamel epithelia formation and maintenance.113