loss-gain-function-approach-to-investigate-early-cell-fate

Loss- and Gain-of-function Approach to Investigate Early Cell Fate Determinants in Preimplantation Mouse Embryos

 Gene silencing and overexpression techniques are instrumental for the identification of genes involved in embryonic development. Direct target gene ...

procedure-for-adaptive-laboratory-evolution-microorganisms-using

Procedure for Adaptive Laboratory Evolution of Microorganisms Using a Chemostat

Natural evolution involves genetic diversity such as environmental change and a selection between small populations. Adaptive laboratory evolution (ALE) ...

Sahmyook University

Korea Research Institute of Bioscience and Bioengineering (KRIBB)

The goal of this study was to fabricate a 3-dimensional (3-D) porous scaffold derived from bladder submucosa (BSM) and further recellularize the scaffold with human bladder cells for cell-based urethral tissue engineering. Fresh porcine BSM was soaked with peracetic acid (PAA) at different concentrations (0,1,3,5 and 10%) and then treated with Triton X-100 for decellularization. DNA content analysis showed that nuclear material was removed from the BSM scaffold. Treatment with 5% PAA led to high porosity on the surface of the matrix with retention of less cellular material and maintained about 75% of normal tensile strength. In 3-D dynamic culture, cells formed even multiple layers on the surface of matrix. Cells also penetrated deeper into the lamina propria of the matrix compared to untreated matrix. Immunocytochemical staining indicated that the grafted bladder cells expressed urothelial- and smooth muscle-specific markers both, in vitro and in vivo. This study demonstrates that decellularized/oxidized BSM possesses 3-D porosity for cell infiltration into the matrix. Further, cells seeded on decellularized/oxidized BSM and grown in dynamic culture, significantly promoted cell-matrix penetration in vitro and promoted cell growth in vivo. Scaffolds with such characteristics have potential applications in cell-based urological tissue engineering.

Optimization of a natural collagen scaffold to aid cell-matrix penetration for urologic tissue engineering.

Little is known about the function of natural IgM autoantibodies, especially that of IgM anti-leukocyte autoantibodies (IgM-ALA). Natural IgM-ALA are present at birth and characteristically increase during inflammatory and infective conditions. Our prior clinical observations and those of other investigators showing fewer rejections in renal and cardiac allografts transplanted into recipients with high levels of IgM-ALA led us to investigate whether IgM-ALA regulate the inflammatory response. In this article, we show that IgM, in physiologic doses, inhibit proinflammatory cells from proliferating and producing IFN-γ and IL-17 in response to alloantigens (MLR), anti-CD3, and the glycolipid α-galactosyl ceramide. We showed in an IgM knockout murine model, with intact B cells and regulatory T cells, that there was more severe inflammation and loss of function in the absence of IgM after renal ischemia reperfusion injury and cardiac allograft rejection. Replenishing IgM in IgM knockout mice or increasing the levels of IgM-ALA in wild-type B6 mice significantly attenuated the inflammation in both of these inflammatory models that involve IFN-γ and IL-17. The protective effect on renal ischemia reperfusion injury was not observed using IgM preadsorbed with leukocytes to remove IgM-ALA. We provide data to show that the anti-inflammatory effect of IgM is mediated, in part, by inhibiting TLR-4-induced NF-κB translocation into the nucleus and inhibiting differentiation of activated T cells into Th-1 and Th-17 cells. These observations highlight the importance of IgM-ALA in regulating excess inflammation mediated by both innate and adaptive immune mechanisms and where the inflammatory response involves Th-17 cells that are not effectively regulated by regulatory T cells.

Natural IgM anti-leukocyte autoantibodies attenuate excess inflammation mediated by innate and adaptive immune mechanisms involving Th-17.

The aim of this pilot study was to evaluate the efficiency, difficulty and operator's preference of a digital impression compared with a conventional impression for single implant restorations.

Digital vs. conventional implant impressions: efficiency outcomes.

Abstract Computer guided implant treatment allows implants and associated restorations to be precisely placed at the same procedure directly through the gingiva with reduced post-operative complications and surgical time. When bone height is adequate but very narrow, the virtual guided sleeve is often placed too deeply into the ridge crest interfering with the seating of the surgical template. This case report of a patient exhibiting very narrow residual ridges due to severe resorption describes a new computer guided procedure using a single surgical template maintaining bone height and immediate restoration without a mucoperiosteal flap. The success of this technique is the result of innovative modifications in the software as well as instrumentation. Modifications include planning a different implant length virtually to raise the position of guide sleeves, alteration of drilling sequences, modifications of the start drill, incorporation of osteotomes, and use of an alternative implant seating mount. The combination of these methods allows for deeper site preparation and implant seating beyond the default settings, without any crestal bone reduction. These modifications not only make the guided concept possible for the entire preparation and seating procedures, but also allow for the slight removal of bone that would interfere with the implant seating through the surgical template without a mucoperiosteal flap. This new approach to computer guided surgery maintains prosthetic precision in the fabrication of a provisional restoration prior to implantation with minimal delivery adjustments using prefabricated conical abutments when placing implants at differing levels into the high narrow ridge.

Guided Flapless Surgery With Immediate Loading For The High Narrow Ridge Without Grafting.

What's known on the subject? and What does the study add? The association between subjects with the genetic variation of 8q24 and the risk of development of prostate cancer in Korean men was found. As a result of haplotype analysis, [AGC] and [CTA] carriers showed a significant association with prostate cancer risk. This is clinically meaningful as an initial study on genetic susceptibility to prostate cancer in Korean men and the first report of 8q24 haplotypes in an Asian population.

Association of common variations of 8q24 with the risk of prostate cancer in Koreans and a review of the Asian population.

Computer guided implant treatment allows implants and associated restorations to be precisely placed during the same procedure directly through the gingiva with reduced postoperative complications and surgical time. When bone height is adequate but very narrow, the virtual guided sleeve is often placed too deeply into the ridge crest interfering with the seating of the surgical template. This case report of a patient exhibiting very narrow residual ridges due to severe resorption describes a new computer guided procedure using a single surgical template maintaining bone height and immediate restoration without a mucoperiosteal flap. The success of this technique is the result of innovative modifications in the software as well as instrumentation. Modifications include planning a different implant length virtually to raise the position of guide sleeves, alteration of drilling sequences, modifications of the start drill, incorporation of osteotomes, and use of an alternative implant seating mount. The combination of these methods allows for deeper site preparation and implant seating beyond the default settings, without any crestal bone reduction. These modifications not only make the guided concept possible for the entire preparation and seating procedures, but also allow for the slight removal of bone that would interfere with the implant seating through the surgical template without a mucoperiosteal flap. This new approach to computer guided surgery maintains prosthetic precision in the fabrication of a provisional restoration prior to implantation with minimal delivery adjustments using prefabricated conical abutments when placing implants at differing levels into the high narrow ridge.

Guided flapless surgery with immediate loading for the high narrow ridge without grafting.

The purpose of this study was to investigate the shear bond strength of the porcelain repair system on alumina and zirconia core ceramics, comparing this strength with that of veneering porcelain.

Bond strength of the porcelain repair system to all-ceramic copings and porcelain.

The accuracy and efficiency of digital implant impressions should match conventional impressions. Comparisons should be made with clinically relevant data.

An evaluation of student and clinician perception of digital and conventional implant impressions.

The accuracy of digital impressions greatly influences their clinical viability in implant restorations. The aim of this study was to compare the accuracy of gypsum models acquired from the conventional implant impression to digitally milled models created from direct digitalization by three-dimensional analysis.

Accuracy of digital versus conventional implant impressions.

Photodynamic therapy (PDT) is a method to treat cancers using photosensitizer and light. PDT has been tried for several tumors. However, the clinical applications are limited by the toxicity of photosensitizer and narrow effect. Sulforaphane (SFN) is a material of isothiocyanate group and known to have anticancer effect. We evaluated the cytotoxic effect of PDT combined with SFN on human head and neck cancer cells. We measured the cell viability, extent of apoptosis and necrosis, reactive oxygen species (ROS) generation and caspase activation. Cell viability was decreased significantly by combination treatment. Cellular apoptosis and necrosis were increased in combination treatment compared to SFN or PDT. ROS generation was also higher in combination treatment than single treatment. In combination treatment group, apoptosis and necrosis were decreased by administration of sodium azide (SA) which is scavenger of ROS. Increased caspase activation in combination treatment was also inhibited by SA. Combination of PDT and SFN led to enhanced cytotoxic effect on head and neck cancer cells. Combination treatment promoted the ROS generation, which induced cell death through activation of caspase pathway.

Enhancement of cytotoxic effect on human head and neck cancer cells by combination of photodynamic therapy and sulforaphane.

The objectives of this case series are to describe a novel clinical approach to treat completely edentulous patients and determine its viability. Computer-guided implant planning was used to create a screw-retained surgical template (ST) supported by transitional implants and a fixed screw-retained provisional prosthesis supported by the transitional implants at the time of definitive implant placement.

Innovative approach to computer-guided surgery and fixed provisionalization assisted by screw-retained transitional implants.

Understanding the morphological structure of membranes is essential to improve performance of membrane-based applications. In this paper, macroporous membranes were investigated and two methods introduced as an alternative for characterization of stereo-structure of the membranes. We combined the use of synchrotron X-ray nanotomography and small-angle X-ray scattering to examine the internal structure of cellulose acetate membranes with studies of the capture of surface-modified gold nanoparticles within these membranes. Finally, the morphological structures of macroporous membranes were visualized and their relationships with penetration tendency of surface-modified gold nanoparticles were explained.

The Internal Structure of Macroporous Membranes and Transport of Surface-Modified Nanoparticles.

The accuracy of digital impressions and the milling of implant crowns greatly influence the clinical outcome of implant restorations.

ArticleTotal : 2	Year
Publication title Cited by 2	2016
Publication title Cited by 11	2016

Article	Year
Optimization of a natural collagen scaffold to aid cell-matrix penetration for urologic tissue engineering. Biomaterials\| PubMed ID: 19427687	2009
Natural IgM anti-leukocyte autoantibodies attenuate excess inflammation mediated by innate and adaptive immune mechanisms involving Th-17. Journal of immunology (Baltimore, Md. : 1950)\| PubMed ID: 22262657	2012
Digital vs. conventional implant impressions: efficiency outcomes. Clinical oral implants research\| PubMed ID: 22353208	2013
Guided Flapless Surgery With Immediate Loading For The High Narrow Ridge Without Grafting. The Journal of oral implantology\| PubMed ID: 22380871	2012
Association of common variations of 8q24 with the risk of prostate cancer in Koreans and a review of the Asian population. BJU international\| PubMed ID: 22583965	2012
Guided flapless surgery with immediate loading for the high narrow ridge without grafting. The Journal of oral implantology\| PubMed ID: 22783940	2012
Bond strength of the porcelain repair system to all-ceramic copings and porcelain. Journal of prosthodontics : official journal of the American College of Prosthodontists\| PubMed ID: 23725343	2014
An evaluation of student and clinician perception of digital and conventional implant impressions. The Journal of prosthetic dentistry\| PubMed ID: 23998623	2013
Accuracy of digital versus conventional implant impressions. Clinical oral implants research\| PubMed ID: 24720423	2015
Enhancement of cytotoxic effect on human head and neck cancer cells by combination of photodynamic therapy and sulforaphane. General physiology and biophysics\| PubMed ID: 25395599	2015
Innovative approach to computer-guided surgery and fixed provisionalization assisted by screw-retained transitional implants. The International journal of oral & maxillofacial implants\| PubMed ID: 25830401	2015
The Internal Structure of Macroporous Membranes and Transport of Surface-Modified Nanoparticles. Microscopy and microanalysis : the official journal of Microscopy Society of America, Microbeam Analysis Society, Microscopical Society of Canada\| PubMed ID: 26156882	2015
Accuracy in the digital workflow: From data acquisition to the digitally milled cast. The Journal of prosthetic dentistry\| PubMed ID: 26803173	2016

Sang J. Lee

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