Correction to: Osteogenic prospective of deriving human dental stem cells in collagen matrix boost.

The original version of this article unfortunately contained a mistake. The country was incorrect in the authors affiliations. It should read as "ROC". The corrected affiliations are given below.

Osteogenic prospective of deriving human dental stem cells in collagen matrix boost.

Stem cells derived from oral tissue represent a highly attractive alternative source for clinical bone regeneration because they can be collected by non-invasive or minimally invasive procedures. Herein, we describe the human dental stem cells (DSCs) deriving from buccal fat pads (BFP), dental pulp (DP) of impacted teeth, and periodontal ligaments (PDL) to obtain BFPSCs, DPSCs, and PDLSCs, respectively. Cells were purified with selected medium and expanded through passages in stem cell culture medium. Purified cells were characterized for stemness by their growth rate, immunostaining, and multilineage differentiation ability. They showed plastic adherence, expression of stemness-specific markers, and multilineage differentiation potential. Immunocytochemistry analysis confirmed that DPSCs had more osteogenic potential than BFSCs and PDLSCs. Calcium-rich deposits, evaluated by von Kossa and Alizarin red staining, showed greater mineralization when DPSCs were cultured on collagen type I matrix than without collagen. Furthermore, DPSC-seeded collagen type I matrix maintained consistent osteogenesis and boosted mineral formation by 1-2 weeks over that in DPSCs cultured without collagen. Radiographic analysis of DPSC-seeded collagen type I matrix transplanted into rat cranial defects showed significant bone regeneration after 8 weeks. These results suggested that the redundant oral tissue can be used as a source of adult multipotent stem cells for clinical bone regeneration. Triple overlay images with biomarkers (red), nuclei (blue) and bright field morphology of DPSCs. The specifically osteo-differentiation shown by osteocalcin (left) expression and lack of sox9 (right) expressed in the images below which were cultured with collagen matrix, contrast with no collagen matrix group above.

Cyclosporin-induced downregulation of the expression of E-cadherin during proliferation of edentulous gingival epithelium in rats.

BACKGROUND: To examine the role of E-cadherin in epithelial hyperplasia of cyclosporin A (CsA)-induced gingival enlargement, mRNA and protein levels of E-cadherin, beta-catenin, proliferating cell nuclear antigen (PCNA), and Cyclin D1 were examined in the edentulous gingiva of rats following CsA treatment. METHODS: Three weeks after the extraction of all maxillary molars, 20 male Sprague-Dawley rats were assigned to a CsA-fed group (30 mg/kg daily) or a control group. Five rats per group were sacrificed at weeks 1 and 4. Edentulous ridge specimens were taken, and the expression levels of E-cadherin, beta-catenin, Cyclin D1, and PCNA mRNAs were estimated by reverse transcription-polymerase chain reaction (RT-PCR). Tissue specimens of the week 4 groups were examined using immunohistochemical (IHC) staining for proteins. RESULTS: The mRNA expression of E-cadherin was significantly weaker in the CsA-treated group than the control group at both times. Using IHC staining, a weaker level of membrane-bonded E-cadherin was also observed in the gingival epithelial cells in the CsA group than in controls. By contrast, significantly stronger beta-catenin and Cyclin D1 mRNA expressions and protein levels were found in CsA-treated rats than controls by RT-PCR and immunohistochemistry at week 4, whereas PCNA production was stronger at both times. CONCLUSIONS: CsA treatment reduced the production of E-cadherin but increased the production of beta-catenin, Cyclin D1, and PCNA. Thus, CsA may downregulate E-cadherin gene expression, leading to the epithelial cell proliferation of gingival overgrowth.

Which test is a better strategy to determine the outcome of atypical glandular cell-categorized Pap smears? Immunocytochemical p16INK4A expression or human papillomavirus test--a retrospective cohort study.

OBJECTIVE: This study was to correlate high-risk human papillomavirus (HR-HPV) viral load to p16(INK4A) (p16) expression in atypical glandular cell (AGC)-categorized Pap smears with follow-up biopsies for elucidating their relationships. METHODS: We enrolled 36 AGC-categorized Pap smears with subsequent follow-up biopsies. HR-HPV viral load was determined by Hybrid Capture II assay in each AGC-diagnosed Pap smear. Both smears and biopsies were immunostained with a primary anti-p16 antibody, clone E6H4. Correlations between HR-HPV viral load in each AGC-diagnosed Pap smear and p16 expression of smears with follow-up biopsies were performed. RESULTS: Comparative analysis of two tests disclosed both consistencies and discrepancies. There were significant differences (P=0.02) between negative or weak p16 expression of Pap smears with the presence of reactive lesion or LSILs/CIN1s in follow-up biopsies and negative HR-HPV viral load. However, no significant difference (P=0.317) was found between p16 expression of Pap smears with the presence of HSIL/CIN2, 3 and AIS or adenocarcinoma in follow-up biopsies and high HR-HPV viral load. In addition, there were significant differences (P=0.012) in specificity, but no significant differences were found in sensitivity (P=0.604), positive and negative predictive value (P=0.066 and 0.264) between p16 immunoexpression and HR-HPV viral load. CONCLUSIONS: Pathogenic activity of HR-HPV was indicated by p16 expression on smears and tissue sections, which appears to be a better strategy than HR-HPV viral load test for the detection of clinically insignificant lesions from AGC-categorized Pap smears.