Functional tooth restoration by next-generation bio-hybrid implant as a bio-hybrid artificial organ replacement therapy

Bio-hybrid artificial organs are an attractive concept to restore organ function through precise biological cooperation with surrounding tissues in vivo. However, in bio-hybrid artificial organs, an artificial organ with fibrous connective tissues, including muscles, tendons and ligaments, has not been developed. Here, we have enveloped with embryonic dental follicle tissue around a HA-coated dental implant, and transplanted into the lower first molar region of a murine tooth-loss model. We successfully developed a novel fibrous connected tooth implant using a HA-coated dental implant and dental follicle stem cells as a bio-hybrid organ. This bio-hybrid implant restored physiological functions, including bone remodelling, regeneration of severe bone-defect and responsiveness to noxious stimuli, through regeneration with periodontal tissues, such as periodontal ligament and cementum. Thus, this study represents the potential for a next-generation bio-hybrid implant for tooth loss as a future bio-hybrid artificial organ replacement therapy

Quadrupolar effect and rattling motion in heavy fermion superconductor PrOs_4Sb_{12}

The elastic properties of a filled skutterudite PrOs_4Sb_{12} with a heavy Fermion superconductivity at T_C=1.85 K have been investigated. The elastic softening of (C_{11}-C_{12})/2 and C_{44} with lowering temperature down to T_C indicates that the quadrupolar fluctuation due to the CEF state plays a role for the Cooper paring in superconducting phase of PrOs_4Sb_{12}. A Debye-type dispersion in the elastic constants around 30 K revealed a thermally activated Gamma_{23} rattling due to the off-center Pr-atom motion obeying tau=tau_{0}exp(E/k_{B}T) with an attempt time tau_0=8.8*10^{-11} sec and an activation energy E=168 K. It is remarkable that the charge fluctuation of the off-center motion with Gamma_{23} symmetry may mix with the quadrupolar fluctuation and enhance the elastic softening of (C_{11}-C_{12})/2 just above T_C.Comment: 5 pages, 4 figures, to be published to Phys. Rev.

Effect of Retinoic Acid on the Growth and the Expression of the Human Papillomavirus 16 E6 and E7 Genes of the Cervical Carcinoma Cell Lines

Human papillomavirus type 16 (HPV16) is involved in the development of cervical carcinoma and its viral gene products E6 and E7 are believed to be essential for the carcinogenic process. We analyzed the effect of retinoic acid (RA) on the growth and/or HPV16 E6 and E7 gene expression in the HPV16-containing cervical carcinoma cell lines SiHa, CaSki and QG-U and the HPV-free cell lines C33A and EBC-1. RA (10-6 M) suppressed the growth of SiHa cells by more than 90% and of QG-U cells by about 40% ; however, the growth of CaSki, C33A and EBC-1 cells was not affected by RA. Semi-quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) was applied for investigation of the relationship between RA and the level of HPV16 E6/E7 mRNA. As a result, the E6/E7 mRNA level in SiHa and QG-U was reduced by RA by about 60% and 75%, respectively, while RA had no obvious effect on the E6 and E7 gene expression in CaSki cells. The chloramphenicol acetyltransfer-ase (CAT) assay showed that transcription driven by HPV16 non-coding region (NCR) was suppressed by RA by about 75%. These results suggest that at least a part of the growth suppression of SiHa and QG-U by RA is mediated by sup-pression of E6 and E7 expression

A Case of Mucosal Cancer of the Stomach Treated by Endoscopic Submucosal Dissection after Which Nodal Metastasis Became Evident

An 82-year-old male was referred to our institution for evaluation and treatment of a protruding lesion in the stomach. Esophagogastroduodenoscopy (EGD) showed a small protruding lesion and a large superficial elevated lesion on the lesser curvature of the stomach (macroscopic type: 0-I and 0-IIa, resp.). CT and endoscopic ultrasonography (EUS) visualized a small round lymph node (LN) 11 mm in size near the lesser curvature, although submucosal invasion was not evident. These two lesions were resected en bloc by endoscopic submucosal dissection (ESD). Pathological examination of the resected specimen showed moderately differentiated tubular adenocarcinoma (tub2) and well-differentiated tubular adenocarcinoma (tub1), respectively, which were limited to the mucosal layer. Because lymphatic-vascular involvement was not detected by hematoxylin and eosin (HE) staining, additional gastrectomy was not performed. Two months after ESD, follow-up EUS and CT showed an enlarged LN. EUS-guided fine needle aspiration (EUS-FNA) for the LN revealed metastasis. Therefore, total gastrectomy with LN dissection was performed. His postoperative course was uneventful. After discharge, he has been followed up at the outpatient department without any sign of recurrence for 5 years. Histological reexamination of the ESD specimen using immunohistochemistry showed lymphatic invasion of cancer cells in the lamina propria of the 0-I lesion 13 mm in size