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Tania Saskianti,1 Alexander Patera Nugraha,2 Chiquita Prahasanti,3 Diah Savitri Ernawati,4 Kotaro Tanimoto,5 Wibi Riawan,6 Masami Kanawa,7 Takeshi Kawamoto,8,9 Katsumi Fujimoto8,10 1Department of Pediatric Dentistry, Faculty of Dental Medicine, Universitas Airlangga, Surabaya, Indonesia; 2Department of Orthodontics, Faculty of Dental Medicine, Universitas Airlangga, Surabaya, Indonesia; 3Department of Periodontology, Faculty of Dental Medicine, Universitas Airlangga, Surabaya, Indonesia; 4Department of Oral Medicine, Faculty of Dental Medicine, Universitas Airlangga, Surabaya, Indonesia; 5Department of Orthodontics and Craniofacial Developmental Biology, Graduate School of Biomedical & Health Sciences, Hiroshima University, Hiroshima, Japan; 6Biomolecular Biochemistry, Faculty of Medicine, Brawijaya University, Malang, Indonesia; 7Natural Science Center for Basic Research and Development, Hiroshima University, Hiroshima, Japan; 8Department of Dental and Medical Biochemistry, Graduate School of Biomedical & Health Sciences, Hiroshima University, Hiroshima, Japan; 9Writing Center, Hiroshima University, Higashi-Hiroshima, Japan; 10Department of Molecular Biology and Biochemistry, Graduate School of Biomedical & Health Sciences, Hiroshima University, Hiroshima, JapanCorrespondence: Tania Saskianti, Department of Pediatric Dentistry, Faculty of Dental Medicine, Universitas Airlangga, Jalan Prof. Dr. Moestopo No. 47, Surabaya, 60132, Indonesia, Tel +62 81 232014445, Email tania-s@fkg.unair.ac.idBackground: Periodontitis progression is characterized by alveolar bone loss, and its prevention is a major clinical problem in periodontal disease management. Matrix metalloproteinase-8 (MMP-8) has been shown to adequately monitor the treatment of chronic periodontitis patients as gingival crevicular fluid MMP-8s were positively associated with the severity of periodontal disease. Moreover, modulating the vascular endothelial growth factor (VEGF) levels in bones could be a good way to improve bone regeneration and cure periodontitis as VEGF promotes endothelial cell proliferation, proteolytic enzyme release, chemotaxis, and migration; all of which are required for angiogenesis.Purpose: The aim of this study was to determine the effect of hydroxyapatite incorporated with stem cells from exfoliated deciduous teeth (SHED) in Wistar rats’ initial alveolar bone remodeling based on the findings of MMP-8 and VEGF expressions.Methods: A hydroxyapatite scaffold (HAS) in conjunction with SHED was transplanted into animal models with alveolar mandibular defects. A total of 10 Wistar rats (Rattus norvegicus) were divided into two groups: HAS and HAS + SHED. Immunohistochemistry staining was performed after 7 days to facilitate the examination of MMP-8 and VEGF expressions.Results: The independent t-test found significant downregulation of MMP-8 and upregulation VEGF expressions in groups transplanted with HAS in conjunction with SHED compared with the HAS group (p < 0.05).Conclusion: The combination of SHED with HAS on alveolar bone defects may contribute to initial alveolar bone remodeling as evident through the assessments of MMP-8 and VEGF expressions.Keywords: angiogenesis, medicine, osteogenesis, scaffold, tissue engineering

The wettability of a surface of channels filtering liquids and gases under natural conditions of oil and gas reservoirs is one of the parameters that largely determines the filtration. A nature of the filtration channel surface wettability determines a phase permeability, capillary forces and intensity of adsorption at the interface. An ability of the filtration channel surface to be wet by the polar or nonpolar phases of formation fluid and process liquids affects the filtration-capacitive parameters of oil and gas saturated rocks. In this regard, in the development of oil and gas fields, much attention is paid to the study of physicochemical phenomena and processes occurring at the interfaces. An article presents the results of a set of laboratory experiments to study the surface activity of the colloidal system in the form of an emulsion with supercharged nanoparticles. A set of filtration experiments was carried out using the United States Bureau of Mines (USBM) method in order to assess an effect of the emulsion system with nanoparticles on wettability of the surface of oil and gas reservoir rock filtration channels. The research was conducted on rock cores of two oil and gas fields in the Ural-Volga region of the Russian Federation. According to the applied experimental procedure, rock cores were preliminarily maintained under reservoir conditions to give a surface of pore channels the properties close to the natural conditions. After that, the wettability of rocks was assessed by measuring the USBM wettability index before and after filtering the emulsion system with nanoparticles. Analysis of the research results showed that filtration of the emulsion system with high surface activity led to a change in the wettability of rocks from completely hydrophilic (USBM index – 0.60) to completely hydrophobic (USBM index – minus 0.32). The research results allowed to conclude that there is a high potential for application of emulsion systems with supercharged nanoparticles to control the filtration of formation fluids and process liquids in natural oil and gas reservoirs.

Amelogenin with a proline 41 to threonine mutation (P41T) is hydrolyzed at a lower rate by matrix metalloproteinase 20 (MMP20), resulting in an inherited tooth enamel defect, amelogenesis imperfecta (AI). The aim of this study was to elucidate the effect of P41T on the interactions between amelogenin and MMP20, which may contribute to the formation of this type of AI. The interactions of a recombinant wild-type human amelogenin and its P41T mutant with recombinant human MMP20 were compared by substrate competition assay, pull-down assay, and surface plasmon resonance (SPR). The results showed that the binding of the P41T mutant amelogenin for MMP20 was significantly lower than that of wild-type amelogenin. Our study supports a model in which the P41T mutation reduces the interactions between amelogenin and MMP20, leading to decreased degradation of amelogenin by MMP20, and resulting in AI.

Fluorosed enamel is more porous and less mineralized, possibly related to altered amelogenin-modulated crystal growth. The purpose of this study was to examine the role of fluoride in interactions between amelogenin and apatite crystals. Recombinant human amelogenin (rh174) was bound to carbonated hydroxyapatite containing various amounts of fluoride, and analyzed by protein assay, SDS PAGE, and AFM. Interactions between rh174 and fluoride were assayed by isothermal titration calorimetry (ITC). The initial binding rate of rh174, as well as total amount of rh174 bound to fluoride-containing carbonated hydroxyapatite, was greater than that in the control carbonated hydroxyapatite. Fluoride in solution at physiologic (5.3 micromolar, or 0.1 ppm) concentrations showed no significant effect on binding, but higher fluoride levels significantly decreased protein binding. ITC showed no interactions between fluoride and rh174. These results suggest that fluoride incorporation into the crystal lattice alters the crystal surface to enhance amelogenin binding, with no direct interactions between fluoride and amelogenin.

Naturally arising [CD4.sup.+][CD25.sup.+] regulatory T ([T.sub.R]) cells have been shown to prevent and cure murine T cell-mediated colitis. However, their exact mechanism of controlling colitogenic memory [CD4.sup.+] T cells in in vivo systems excluding the initial process of naive T cell activation and differentiation has not been examined to date. Using the colitogenic effector memory ([T.sub.EM]) [CD4.sup.+] cell-mediated colitis model induced by adoptive transfer of colitogenic [CD4.sup.+][CD44.sup.high][CD62L.sup.-] lamina propria (LP) T cells obtained from colitic [CD4.sup.+] [CD45RB.sup.high] T cell-transferred mice, we have shown in the present study that [CD4.sup.+][CD25.sup.+] TR cells are able not only to suppress the development of colitis, Th1 cytokine production, and the expansion of colitogenic LP [CD4.sup.+] [T.sup.EM] cells but also to expand these cells by themselves extensively in vivo. An in vitro coculture assay revealed that [CD4.sup.+][CD25.sup.+] TR cells proliferated in the presence of IL-2-producing colitogenic LP [CD4.sup.+] [T.sub.EM] cells at the early time point (48 h after culture), followed by the acquisition of suppressive activity at the late time point (96 h after culture). Collectively, these data suggest the distinct timing of the IL-2-dependent expansion of [CD4.sup.+][CD25.sup+] [T.sub.R] cells and the their suppressive activity on colitogenic LP [CD4.sup.+] [T.sub.EM] cells. murine colitis model; interleukin-2