-
[show abstract]
[hide abstract]
ABSTRACT: Fusion of the branchial arch derivatives is a crucial event in the development of the craniofacial architecture. Here, we surveyed the gene expression profile, focusing on the fusion process of the mouse mandibular arch at embryonic day 10.5. In order to identify the genes that are relevant to the midline fusion process, we subdivided the mandibular arch medially and laterally, and determined gene expression using microarray and real-time quantitative PCR. By comparing the transcriptomes of the medial and lateral regions, 362 genes were identified as medial region-specific genes, while 346 genes were designated lateral region-specific. Taken with Gene Ontology analysis, KEGG pathways and Ingenuity Pathway Analysis (IPA), a survey of the medial region-specific gene dataset revealed significant expression of the insulin-like growth factor (Igf) family as well as other growth factor families (Hh, Wnt, Tgf-Bmp, Mapk-Fgf and Notch). To determine the discrete expression pattern of Igf family genes in the medial region, we microdissected the medial part of the mandibular arch into epithelial and mesenchymal components, and found that Igf1 was highly expressed in the mesenchyme, Igf2 and Igf1r were expressed in both the midline epithelium and surrounding mesenchyme, and Igfbp5 was highly expressed in the epithelium. Immunohistochemical findings validated the regional Igf gene expression profiles. Our observations suggest that in the merging fusion of the mandibular arch, the Igf cascade may contribute to generation of proliferation pressure from the mesenchyme and preservation of epithelial phenotypes and architecture during mesenchymal confluence.
The International journal of developmental biology 04/2013; · 2.16 Impact Factor
-
Hiroshi Kubo,
Masakazu Shimizu,
Yuji Taya,
Takeshi Kawamoto,
Masahiko Michida,
Emi Kaneko,
Akira Igarashi,
Masahiro Nishimura,
Kazumi Segoshi, Yoshihito Shimazu,
Koichiro Tsuji,
Takaaki Aoba,
Yukio Kato
[show abstract]
[hide abstract]
ABSTRACT: Although ex vivo expanded mesenchymal stem cells (MSC) have been used in numerous studies, the molecular signature and in vivo distribution status of MSC remain unknown. To address this matter, we identified numerous human MSC-characteristic genes--including nine transcription factor genes--using DNA microarray and real-time RT-PCR analyses: Most of the MSC-characteristic genes were down-regulated 24 h after incubation with osteogenesis-, chondrogenesis- or adipogenesis-induction medium, or 48-72 h after knockdown of the nine transcription factors. Furthermore, knockdowns of ETV1, ETV5, FOXP1, GATA6, HMGA2, SIM2 or SOX11 suppressed the self-renewal capacity of MSC, whereas those of FOXP1, SOX11, ETV1, SIM2 or PRDM16 reduced the osteogenic- and/or adipogenic potential. In addition, immunohistochemistry using antibodies for the MSC characteristic molecules--including GATA6, TRPC4, FLG and TGM2--revealed that MSC-like cells were present near the endosteum and in the interior of bone marrow of adult mice. These findings indicate that MSC synthesize a set of MSC markers in vitro and in vivo, and that MSC-characteristic transcription factors are involved in MSC stemness regulation.
Genes to Cells 03/2009; 14(3):407-24. · 2.68 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Phosphoglucosamine mutase (EC 5.4.2.10) catalyzes the interconversion of glucosamine-6-phosphate into glucosamine-1-phosphate, an essential step in the biosynthetic pathway leading to the formation of peptidoglycan precursor uridine 5'-diphospho-N-acetylglucosamine. The gene (glmM) of Escherichia coli encoding the enzyme has been identified previously. We have now identified a glmM homolog in Streptococcus gordonii, an early colonizer on the human tooth and an important cause of infective endocarditis, and have confirmed that the gene encodes phosphoglucosamine mutase by assaying the enzymatic activity of the recombinant GlmM protein. Insertional glmM mutant of S. gordonii did not produce GlmM, and had a growth rate that was approximately half that of the wild type. Morphological analyses clearly indicated that the glmM mutation causes marked elongation of the streptococcal chains, enlargement of bacterial cells, and increased roughness of the bacterial cell surface. Furthermore, the glmM mutation reduces biofilm formation and increases sensitivity to penicillins relative to wild type. All of these phenotypic changes were also observed in a glmM deletion mutant, and were restored by the complementation with plasmid-borne glmM. These results suggest that, in S. gordonii, mutations in glmM appear to influence bacterial cell growth and morphology, biofilm formation, and sensitivity to penicillins.
FEMS Immunology & Medical Microbiology 08/2008; 53(2):166-77. · 2.44 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Inhibitory responses of slowly adapting pulmonary stretch receptor (SAR) activity to CO(2) inhalation (maximal tracheal CO(2) concentration ranging from 9.5 to 12.5%) for approximately 60 s were examined before and after administration of acetazolamide (a carbonic anhydrase inhibitor) or 4-aminopyridine (4-AP, a K(+) channel blocker). The experiments were performed in 35 anesthetized, artificially ventilated rats after unilateral vagotomy. Sixty-eight of eighty-four SARs were inhibited by CO(2) inhalation. The SAR inhibition was attenuated by pretreatment with either acetazolamide (20 mg/kg, n = 10) or 4-AP (0.7 and 2.0 mg/kg, n = 10). In other series of experiments, stainings to show the existence of carbonic anhydrase (CA) enzymatic reaction were not found in the smooth muscle of either extrapulmonary or intrapulmonary bronchi. Protein gene product 9.5 (PGP 9.5)-immunoreactive SAR terminals to form leaflike extensions were found in the bronchioles at different diameters and were smooth-muscle-related receptors. But in the same sections, CA isozyme II-like (erythrocyte CA) immunoreactive SAR terminals were not identified. These results suggest that CO(2)-induced inhibition of SARs may be involved in the CA-dependent CO(2) hydration in addition to the activation of 4-AP sensitive K(+) currents.
Chemical Senses 06/2004; 29(4):351-61. · 2.60 Impact Factor
-
Ryoma Nakao,
Nobuhiro Hanada,
Toshihiko Asano,
Takashi Hara,
Md Abdus Salam,
Khairul Matin, Yoshihito Shimazu,
Tadashi Nakasone,
Shigeo Horibata,
Takaaki Aoba,
Mitsuo Honda,
Teruo Amagasa,
Hidenobu Senpuku
[show abstract]
[hide abstract]
ABSTRACT: Oral-genital contact is one of the risk factors for the transmission of human immunodeficiency virus (HIV) in adults. In recent reports, oral exposure to simian immunodeficiency virus (SIV) was found to have important implications for the achievement of mucosal transmission of HIV in a rhesus monkey animal model. In the present study, we aimed first to establish a small animal model which did not develop tonsils suitable for HIV oral mucosa transmission, using non-obese diabetic/severe combined immunodeficiency (NOD/SCID) mice and NOD/SCID B2m(null) mice grafted with human peripheral blood leucocytes (hu-PBL) and stimulated with interleukin (IL)-4, and second to investigate whether oral exposure to cell-free R5 and X4 HIV-1 could lead to oral transmission of HIV through intact or traumatized mucosal tissues in humanized mice. Both low and high concentrations of cell-free R5 and X4 viruses failed to cause oral transmission with or without trauma in hu-PBL-NOD/SCID and NOD/SCID Beta2m(null) mice, which presented a number of CD4+ cells in gingival tissues and oral cavities with or without tissue injury. The present results show that IL-4-administrated NOD/SCID B2m(null) mice are useful as a small-humanized model for the study of HIV oral infection, which may help to define the window of opportunity for oral transmission by the HIV virus in animal model experiments.
Immunology 07/2003; 109(2):271-82. · 3.32 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: In recent years, the biomineralization process has attracted much interest from academics and industries for potential technological application. The rule in biomineralization is to have a variety of interfaces and surfaces which can act as nucleators. The ultimate step in any biomineralization process, i.e. the deposition of mineral, must conform to the driving forces operating on the system. A new paradigm in the assessment of the driving force for biomineralization is that a variety of ions existing in the mineralizing milieu are not a bystander, but are instead an active player that directly regulates the precipitation process and nature of biogenic apatites. Thus, the most putative stoichiometric model of a biomineral is (Ca)(5-x)(Mg)q(Na)u(HPO4)v(CO3)w(PO4)(3-y)(OH,F)(1-z). Fluoride participates in many aspects of calcium phosphate formation in vivo and has enormous effects on its process and on the nature and properties of the final products. In the development of biogenic apatites, fluoride ion in the mineralizing media is supposed to accelerate the hydrolysis of acidic precursor(s) and increase the growth rates by augmenting the driving force for precipitation. Inhibitory activities of ions and molecules are related to their adsorption onto the apatite surfaces. From theoretical and practical points of view, it is of paramount importance to elucidate and predict the effect and outcome of fluoride (accelerator) and inhibitors of biological relevance, because of their use in combination for healthcare in dentistry and medicine, e.g. prevention of dental caries and calculus deposition and in the formulation of antiosteoporosis treatments.
Journal of Electron Microscopy 02/2003; 52(6):615-25. · 1.31 Impact Factor
-
Hidenobu Senpuku,
Toshihiko Asano,
Khairul Matin,
M Abdus Salam,
Yuzo Tsuha,
Shigeo Horibata, Yoshihito Shimazu,
Yuichi Soeno,
Takaaki Aoba,
Tetsutaro Sata,
Nobuhiro Hanada,
Mitsuo Honda
[show abstract]
[hide abstract]
ABSTRACT: NOD/LtSz-prkdc(scid)/prkdc(scid) (non-obese diabetic-severe combine immunodeficiency; NOD-scid) mice grafted with human peripheral blood lymphoid cells have been used as an in vivo humanized mouse model in various studies. However, cytotoxic human T cells are induced in this model during immune responses, which gives misleading results. To assist in grafting of human lymphocytes without the induction of cytotoxic human T cells, we investigated the effects of T helper type 1 (Th1) and Th2 cytokines on human lymphocyte grafting and migration, as well as the production of immunoglobulin deposited in glomeruli and human immunodeficiency virus-1 (HIV-1) infection using NOD-scid mice. Administration of interleukin-18 (IL-18) and IL-12 enhanced the grafting of human CD4+ and CD8+ T cells in the mice, whereas co-administration prevented grafting due to interferon-gamma-dependent apoptosis. Immunoglobulin A (IgA) deposits were observed in mice treated with IL-18 alone, but not in those given phosphate-buffered saline, IL-12 alone, or IL-18 + IL-12. A high rate of HIV infection was also observed in the IL-18-treated group. Together, these results indicate that IL-18 may be effective for the grafting and migration of CD4+ and CD8+ T cells, except for the induction of apoptosis and regulation of class-switching IgA. IL-18-administered NOD-scid mice provide a useful small humanized model for the study of HIV infection and IgA nephropathy.
Immunology 11/2002; 107(2):232-42. · 3.32 Impact Factor
-
Hidenobu Senpuku,
Toshihiko Asano,
Khairul Matin,
M. Abdus Salam,
YUZO Tsuha,
Shigeo Horibata, Yoshihito Shimazu,
Yuichi Soeno,
Takaaki Aoba,
Tetsutaro Sata,
Nobuhiro Hanada,
Mitsuo Honda
[show abstract]
[hide abstract]
ABSTRACT: SummaryNOD/LtSz-prkdcscid/prkdcscid (non-obese diabetic-severe combine immunodeficiency; NOD-scid) mice grafted with human peripheral blood lymphoid cells have been used as an in vivo humanized mouse model in various studies. However, cytotoxic human T cells are induced in this model during immune responses, which gives misleading results. To assist in grafting of human lymphocytes without the induction of cytotoxic human T cells, we investigated the effects of T helper type 1 (Th1) and Th2 cytokines on human lymphocyte grafting and migration, as well as the production of immunoglobulin deposited in glomeruli and human immunodeficiency virus-1 (HIV-1) infection using NOD-scid mice. Administration of interleukin-18 (IL-18) and IL-12 enhanced the grafting of human CD4+ and CD8+ T cells in the mice, whereas co-administration prevented grafting due to interferon-γ-dependent apoptosis. Immunoglobulin A (IgA) deposits were observed in mice treated with IL-18 alone, but not in those given phosphate-buffered saline, IL-12 alone, or IL-18 + IL-12. A high rate of HIV infection was also observed in the IL-18-treated group. Together, these results indicate that IL-18 may be effective for the grafting and migration of CD4+ and CD8+ T cells, except for the induction of apoptosis and regulation of class-switching IgA. IL-18-administered NOD-scid mice provide a useful small humanized model for the study of HIV infection and IgA nephropathy.
Immunology 10/2002; 107(2):232 - 242. · 3.32 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Osteopontin (OPN) has been proposed to act as a substrate for osteoclast adhesion during bone resorption. The aim of the present study was to examine the presence and distribution of OPN at sites of resorption in traumatized radicular pulp. The upper first molars of 6-week-old male Sprague-Dawley rats were luxated and then repositioned in the original sockets. The animals were sacrificed by intracardiac perfusion at 10 and 14 days after tooth reimplantation. The teeth were decalcified in EDTA and then processed for embedding in paraffin for histochemistry or LR White resin for immunocytochemistry. Odontoclasts were identified by their multinucleated morphology and expression of tartrate-resistant acid phosphatase (TRAP). Osteopontin was immunolocalized using postembedding colloidal gold labeling with a chicken egg yolk anti-rat OPN antibody. After reimplantation of the teeth, TRAP-positive cells were present along the pulp dentin wall. Osteopontin was not consistently detected at exposed predentin/dentin surfaces. However, gold particles were often found at the margin of resorption lacunae. Labeling was also seen over the Golgi region and cytoplasmic vesicles of odontoclasts and of neutrophils and fibroblast-like cells. The results suggest that accumulation of OPN at the predentin/dentin surface is not a prerequisite for adhesion of odontoclasts to the wall substance and that recruited odontoclasts produce OPN locally to mediate cell and/or matrix events within the resorption lacuna.
Journal of Histochemistry and Cytochemistry 08/2002; 50(7):911-21. · 2.72 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: With the specific aim of the examination of tissue-damage and repair of surgically exposed pulp and periapical region in rat With the specific aim of the examination of tissue-damage and repair of surgically exposed pulp and periapical region in rat
molar model, 14 female Sprague-Dawley rats were used. The coronal portion of lower first molars was surgically removed and molar model, 14 female Sprague-Dawley rats were used. The coronal portion of lower first molars was surgically removed and
the teeth remained untreated for 3 weeks prior to euthanasia of the animals. During this experimental period, all animals the teeth remained untreated for 3 weeks prior to euthanasia of the animals. During this experimental period, all animals
were injected with fluorochrome agents twice at the 12th and 19th days, in order to monitor formation of hard tissues in the were injected with fluorochrome agents twice at the 12th and 19th days, in order to monitor formation of hard tissues in the
exposed pulpal chamber and on the surfaces of cementum and alveolar bone. For histologic examination using microradiography exposed pulpal chamber and on the surfaces of cementum and alveolar bone. For histologic examination using microradiography
and fluorescent and light microscopy, resin-embedded ground sections and serial decalcified sections were prepared. Observations and fluorescent and light microscopy, resin-embedded ground sections and serial decalcified sections were prepared. Observations
revealed that: (1) over half of the surgically treated teeth gave rise to the formation of osteodentin so that the exposed revealed that: (1) over half of the surgically treated teeth gave rise to the formation of osteodentin so that the exposed
pulp was partially covered; (2) the number of root canals filled with necrotic tissues was less than 25% of the total teeth pulp was partially covered; (2) the number of root canals filled with necrotic tissues was less than 25% of the total teeth
examined, while the majority comprised vital granulation tissues and newly formed osteodentin, in certain cases with the appearance examined, while the majority comprised vital granulation tissues and newly formed osteodentin, in certain cases with the appearance
of odontoblastic cells aligning on the dentin wall; and (3) active deposition of cementum on the root apex and remodeling of odontoblastic cells aligning on the dentin wall; and (3) active deposition of cementum on the root apex and remodeling
of alveolar bone were prominent in most of the treated teeth. The overall results support the contention that rat molar pulp of alveolar bone were prominent in most of the treated teeth. The overall results support the contention that rat molar pulp
has high potential activities for tissue-repair including hard tissue formation after pulpal exposure to the oral enviroment. has high potential activities for tissue-repair including hard tissue formation after pulpal exposure to the oral enviroment.
Odontology 04/1997; 85(3):419-427. · 1.22 Impact Factor
