9 research outputs found

    EMILIN proteins are novel extracellular constituents of the dentin-pulp complex

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    Odontoblasts and pulp stroma cells are embedded within supramolecular networks of extracellular matrix (ECM). Fibrillin microfibrils and associated proteins are crucial constituents of these networks, serving as contextual scaffolds to regulate tissue development and homeostasis by providing both structural and mechanical properties and sequestering growth factors of the TGF-beta superfamily. EMILIN-1, -2, and -3 are microfibril-associated glycoproteins known to modulate cell behaviour, growth factor activity, and ECM assembly. So far their expression in the various cells of the dentin-pulp complex during development, in the adult stage, and during inflammation has not been investigated. Confocal immunofluorescence microscopy and western blot analysis of developing and adult mouse molars and incisors revealed an abundant presence of EMILINs in the entire dental papilla, at early developmental stages. Later in development the signal intensity for EMILIN-3 decreases, while EMILIN-1 and -2 staining appears to increase in the pre-dentin and in the ECM surrounding odontoblasts. Our data also demonstrate new specific interactions of EMILINs with fibulins in the dentin enamel junction. Interestingly, in dentin caries lesions the signal for EMILIN-3 was significantly increased in inflamed odontoblasts. Overall our findings point for the first time to a role of EMILINs in dentinogenesis, pulp biology, and inflammation

    Regulator of Calcineurin 1 in Periodontal Disease

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    Nuclear factor of activated T-cells (NFAT) and NF-kB pathway associated processes are involved in the pathogenesis of various inflammatory disorders, for example, periodontal disease. The activation of these pathways is controlled by the regulator of calcineurin 1 (RCAN1). The aim of this study was to elucidate the role of RCAN1 in periodontal disease. Healthy and inflamed periodontal tissues were analyzed by immunohistochemistry and immunofluorescence using specific rabbit polyclonal anti-RCAN1 antibodies. For expression analysis human umbilical vein endothelial cells (HUVEC) were used. HUVEC were incubated for 2h with Vascular Endothelial Growth Factor (VEGF) or with wild type and laboratory strains of Porphyromonas gingivalis (P. gingivalis). Expression analysis of rcan1 and cox2 was done by real time PCR using specific primers for rcan1.4 and cox2. The expression of rcan1 was found to be significantly suppressed in endothelial cells of chronically inflamed periodontal tissues compared to healthy controls. Rcan1 and cox2 were significantly induced by VEGF and wild type and laboratory P. gingivalis strains. Interestingly, the magnitude of the rcan1 and cox2 induction was strain dependent. The results of this study indicate that RCAN1 is suppressed in endothelial cells of chronically inflamed periodontal tissues. During an acute infection, however, rcan1 seems to be upregulated in endothelial cells, indicating a modulating role in immune homeostasis of periodontal tissues

    Epidural lornoxicam administration - innocent

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    WOS: 000249938200010PubMed ID: 17823047We aimed to determine the analgesic efficacy and clincial or histopathological neurotoxicity of epidural single-dose lornoxicam. Caudal epidural catheters were inserted into 28 rabbits, divided into four groups, on day 1. Pain latency and degree of motor and sensory loss for each animal for different concentrations of lornoxicam were determined on day 2. All animals were sacrificed on day 3 and laminectomy was performed. Five-mu m thick sections of spinal cord, obtained from two segments caudal and two segments rostral from tip of the catheter, were fixed and were stained and evaluated by light microscopy. Lornoxicam produced dose-dependent analgesia (increase in pain latency), brief, mild and reversible motor and sensory block, and histopathological signs of neurotoxicity. Clinical application of epidural lornoxicam should proceed with caution. (c) 2006 Elsevier Ltd. All rights reserved

    The Ca2+-binding protein calretinin is selectively enriched in a subpopulation of the epithelial rests of Malassez

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    During tooth development, the inner and outer enamel epithelia fuse by mitotic activity to produce a bilayered epithelial sheath termed Hertwig's epithelial root sheath (HERS). The epithelial rests of Malassez (ERM) are the developmental residues of HERS and remain in the adult periodontal ligament (PDL). Although the cellular regulation of the Ca2+-binding proteins parvalbumin, calbindin-D28k, and calretinin has been reported in the inner and outer enamel epithelia during tooth development, an involvement of Ca2+-binding proteins in the ERM has not so far been characterized. Among the three Ca2+-binding proteins tested (calbindin D28k, parvalbumin, calretinin), we have only been able to detect calretinin in a subpopulation of adult rat molar ERM, by using quantitative immunohistochemical and confocal immunofluorescence techniques. TrkA (a marker for ERM) is present in numerous epithelial cell clusters, whereas calretinin has been localized in the cytosol and perinuclear region of a subpopulation of TrkA-positive cells. We conclude that, in inner and outer enamel epithelial cells, Ca2+ is regulated by calbindin, parvalbumin, and calretinin during tooth development, whereas in the ERM of adult PDL, Ca2+ is regulated only by calretinin. The expression of Ca2+-binding proteins is restricted in a developmental manner in the ERM

    Epithelial loss of mitochondrial oxidative phosphorylation leads to disturbed enamel and impaired dentin matrix formation in postnatal developed mouse incisor

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    The formation of dentin and enamel matrix depends on reciprocal interactions between epithelial-mesenchymal cells. To assess the role of mitochondrial function in amelogenesis and dentinogenesis, we studied postnatal incisor development in K320E-Twinkle(Epi) mice. In these mice, a loss of mitochondrial DNA (mtDNA), followed by a severe defect in the oxidative phosphorylation system is induced specifically in Keratin 14 (K14+) expressing epithelial cells. Histochemical staining showed severe reduction of cytochrome c oxidase activity only in K14+epithelial cells. In mutant incisors, H&E staining showed severe defects in the ameloblasts, in the epithelial cells of the stratum intermedium and the papillary cell layer, but also a disturbed odontoblast layer. The lack of amelogenin in the enamel matrix of K320E-Twinkle(Epi) mice indicated that defective ameloblasts are not able to form extracellular enamel matrix proteins. In comparison to control incisors, von Kossa staining showed enamel biomineralization defects and dentin matrix impairment. In mutant incisor, TUNEL staining and ultrastructural analyses revealed differentiation defects, while in hair follicle cells apoptosis is prevalent. We concluded that mitochondrial oxidative phosphorylation in epithelial cells of the developed incisor is required for Ca2+homeostasis to regulate the formation of enamel matrix and induce the differentiation of ectomesenchymal cells into odontoblasts

    The colocalizations of pulp neural stem cells markers with dentin matrix protein-1, dentin sialoprotein and dentin phosphoprotein in human denticle (pulp stone) lining cells

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    Background: The primary dentin, secondary dentin, and reactive tertiary dentin are formed by terminal differentiated odontoblasts, whereas atubular reparative tertiary dentin is formed by odontoblast-like cells. Odontoblast-like cells differentiate from pulpal stem cells, which express the neural stem cell markers nestin, S100 beta, Sox10, and P0. The denticle (pulp stone) is an unique mineralized extracellular matrix that frequently occurs in association with the neurovascular structures in the dental pulp. However, to date, the cellular origin of denticles in human dental pulp is unclear. In addition, the non-collagenous extracellular dentin matrix proteins dentin matrix protein 1 (DMP1), dentin sialoprotein (DSP), and dentin phosphoprotein (DPP) have been well characterized in the dentin matrix, whereas their role in the formation and mineralization of the denticle matrix remains to be clarified. Methods: To characterize the formation of denticle, healthy human third molars (n = 59) were completely sectioned and evaluated by HE staining in different layers at 720 mu m intervals. From these samples, molars with (n = 5) and without denticles (n = 8) were selected. Using consecutive cryo-sections from a layer containing denticles of different sizes, we examined DMP1, DSP, and DPP in denticle lining cells and tested their co -localizations with the glial stem cell markers nestin, S100 beta, Sox10, and P0 by quantitative and double staining methods. Results: DMP1, DSP and DPP were found in odontoblasts, whereas denticle lining cells were positive only for DMP1 and DSP but not for DPP. Nestin was detected in both odontoblasts and denticle lining cells. S100 beta, Sox10, and P0 were co-localized with DMP1 and DSP in different subpopulations of denticle lining cells. Conclusions: The co-localization of S100 beta, Sox10, and P0 with DMP1 and DSP in denticle lining cells suggest that denticle lining cells are originated from glial and/or endoneurial mesenchymal stem cells which are involved in biomineralization of denticle matrix by secretion of DMP1 and DSP. Since denticles are atubular compared to primary, secondary, reactionary tertiary dentin and denticle formed by odontoblasts, our results suggest that DPP could be one of the proteins involved in the complex regulation of dentinal tubule formation. (c) 2021 Elsevier GmbH. All rights reserved

    Comprehensive Analysis of VEGFR2 Expression in HPV-Positive and -Negative OPSCC Reveals Differing VEGFR2 Expression Patterns

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    Simple Summary:& nbsp;Up to 50% of oropharyngeal squamous cell carcinomas (OPSCC) are associated with human papillomavirus type 16 (HPV16), the annual incidence of which is steadily increasing. HPV-positive and -negative OPSCC exhibit a different biology, which is characterized by distinct mutation signatures and expression patterns. It is known that VEGFR2 is commonly overexpressed in HNSCC, but the influence of HPV on VEGFR2 in OPSCC is still unknown, although VEGFR2 has emerged as a promising target in tumor therapy. The aim of our study was to evaluate whether HPV exerts specific effects on VEGFR2 expression in OPSCC and thus possibly on the regulation of vascularization. Interestingly, while HPV-negative carcinoma upregulates VEGFR2 in tumor cells, in HPV-positive carcinoma VEGFR2 is upregulated in tumor-supporting blood vessels. HPV-positive OPSCC with high VEGFR2 expression is associated with poor prognosis, supporting the prognostic significance of deregulated VEGF signaling for OPSCC patients. VEGF signaling regulated by the vascular endothelial growth factor receptor 2 (VEGFR2) plays a decisive role in tumor angiogenesis, initiation and progression in several tumors including HNSCC. However, the impact of HPV-status on the expression of VEGFR2 in OPSCC has not yet been investigated, although HPV oncoproteins E6 and E7 induce VEGF-expression. In a series of 56 OPSCC with known HPV-status, VEGFR2 expression patterns were analyzed both in blood vessels from tumor-free and tumor-containing regions and within tumor cells by immunohistochemistry using densitometry. Differences in subcellular colocalization of VEGFR2 with endothelial, tumor and stem cell markers were determined by double-immunofluorescence imaging. Immunohistochemical results were correlated with clinicopathological data. HPV-infection induces significant downregulation of VEGFR2 in cancer cells compared to HPV-negative tumor cells (p = 0.012). However, with respect to blood vessel supply, the intensity of VEGFR2 staining differed only in HPV-positive OPSCC and was upregulated in the blood vessels of tumor-containing regions (p < 0.0001). These results may suggest different routes of VEGFR2 signaling depending on the HPV-status of the OPSCC. While in HPV-positive OPSCC, VEGFR2 might be associated with increased angiogenesis, in HPV-negative tumors, an autocrine loop might regulate tumor cell survival and invasion.</p

    A province-based study using sampling method to investigate the prevalence of cystic echinococcosis among primary school children in Manisa, Turkey

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    WOS: 000249681300006PubMed ID: 17603988A province-based field study using a portable ultrasound scanner (US) was performed for the first time using sampling method to investigate the prevalence of cystic echinococcosis (CE) in primary school children in Manisa, Turkey. A total of 6093 children from 37 primary schools was selected as the representative sample of the total number of 166,766 primary school children, and examined by the US. Prevalence was found to be 0.15%, as nine children were diagnosed with CE, seven new and two previously operated. A questionnaire applied to the children revealed no significant relationship between the risk factors and the infection (P > 0.05). In conclusion, it would be advisable to repeat the study at the same schools in eight years' time, in order to evaluate the efficacy of the control programs, since nearly all students involved in this study will have graduated by then. Besides, it is recommended to choose a sampling group to find the prevalence of an infection in a defined region. (c) 2007 Elsevier B.V. All rights reserved

    Upregulation of AKR1C1 and AKR1C3 expression in OPSCC with integrated HPV16 and HPV-negative tumors is an indicator of poor prognosis

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    Different studies have shown that HPV16-positive OPSCC can be subdivided based on integration status (integrated, episomal and mixed forms). Because we showed that integration neither affects the levels of viral genes, nor those of virally disrupted human genes, a genome-wide screen was performed to identify human genes which expression is influenced by viral integration and have clinical relevance. Thirty-three fresh-frozen HPV-16 positive OPSCC samples with known integration status were analyzed by mRNA expression profiling. Among the genes of interest, Aldo-keto-reductases 1C1 and 1C3 (AKR1C1, AKR1C3) were upregulated in tumors with viral integration. Additionally, 141 OPSCC, including 48 HPV-positive cases, were used to validate protein expression by immunohistochemistry. Results were correlated with clinical and histopathological data. Non-hierarchical clustering resulted in two main groups differing in mRNA expression patterns, which interestingly corresponded with viral integration status. In OPSCC with integrated viral DNA, often metabolic pathways were deregulated with frequent upregulation of AKR1C1 and AKR1C3 transcripts. Survival analysis of 141 additionally immunostained OPSCC showed unfavorable survival rates for tumors with upregulation of AKR1C1 or AKR1C3 (both p <0.0001), both in HPV-positive (p <= 0.001) and -negative (p <= 0.017) tumors. OPSCC with integrated HPV16 show upregulation of AKR1C1 and AKR1C3 expression, which strongly correlates with poor survival rates. Also in HPV-negative tumors, upregulation of these proteins correlates with unfavorable outcome. Deregulated AKR1C expression has also been observed in other tumors, making these genes promising candidates to indicate prognosis. In addition, the availability of inhibitors of these gene products may be utilized for drug treatment
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