• 제목/요약/키워드: Adhesion effort

검색결과 33건 처리시간 0.025초

Clinical and molecular biological aspect of the hyaluronidases: basis and clinical overview for oriental medical application

  • Kim, Cheorl-Ho;Lee, Dong-Gyu;Jang, Jun-Hyouk;Kim, Jong-De;Nam, Kyung-Soo;Kim, Jeong-Joong;Park, Jong-Kun;Choo, Young-Kug;Kim, Hyung-Min;Lee, Young-Choon
    • Advances in Traditional Medicine
    • /
    • 제1권1호
    • /
    • pp.8-27
    • /
    • 2000
  • Components of extracellular matrix and the matrix-degrading enzymes are some of the key regulators of tumor metastasis and angiogenesis. Hyaluronic acid (HA), a matrix glycosaminoglycan, is known to promote tumor adhesion and migration, and its small fragments are angiogenic. Until now, we have compared levels of hyaluronidase, an enzyme that degrade HA, in normal adult prostate, benign prostate hyperplasia and prostate cancer tissues and in conditioned media from epithelial explant cultures, using a substrate (HA)-gel assay and ELISA-like assay (Kim et al., unpublished results). The present review described an overall characterization of hyaluronidases and its application to human diseases. The hyaluronidases are a family of enzymes that have, until recently, deed thorough explication. The substrate for these enzymes, hyaluronan, is becoming increasingly important, recognized now as a major participant in basic processes such as cell motility, wound healing, embryogenesis, and implicated in cancer progression. And in those lower life forms that torment human beings, hyaluronidase is associated with mechanisms of entry and spread, e.g. as a virulence factor for bacteria, for tissue dissection in gas gangrene, as a means of treponema spread in syphilis, and for penetration of skin and gut by nematode parasites. Hyaluronidase also comprises a component of the venom of a wide variety of organisms, including bees, wasps, hornets, spiders, scorpions, sh, snakes and lizards. Of particular interest is the homology between some of these venom hyaluronidases and the enzyme found in the plasma membrane of mammalian spermatozoa, attesting to the ancient nature of the conserved sequence, a 36% identity in a 300 amino acid stretch of the enzyme protein. Clearly, hyaluronidase is of biological interest, being involved in the pathophysiology of so many important' human disorders. Greater effort should be made in studying this family of enzymes that have, until recently, been overlooked. Also, oriental medical application of the hyaluronidase will be discussed with respect to inhibition and suppression of inflammation and malignacy.

  • PDF

A STUDY ON THE ADHESION OF A SOFT LINER CONTAINING 4-META TO THE BASE METAL ALLOY AND ITS VISCOELASTIC PROPERTY

  • Park Hyun-Joo;Kim Chang-Whe;Kim Yung-Soo
    • 대한치과보철학회지
    • /
    • 제41권6호
    • /
    • pp.732-746
    • /
    • 2003
  • Statement of problem. Soft lining materials, also referred to as tissue conditioning materials, tissue heating materials, relining materials, soft liners or tissue conditioners, were first introduced to dentistry by a plastic manufacturer in 1959. Since the introduction of the materials to the dental field, their material properties have been continually improved through the effort of many researchers. Soft lining materials have become widely accepted, particularly by prosthodontists, because of their numerous clinical advantages and ease of manipulation. Unfortunately, few reports have been issued upon the topic of increasing the bond strength between the base metal alloy used in cast denture bases and PMMA soft liner modified with 4-META, nor upon the pattern of debonding and material change in wet environment like a intra oral situation. Purpose. The purposes of this study were comparing the bond strength between base metal alloy used for the cast denture bases and PMMA soft liner modified with 4-META, and describing the pattern of debonding and material property change in wet environment like the intraoral situation. Material and Methods. This study consisted of four experiments: 1. The in vitro measurement of shear bond strength of the adhesive soft liner. 2. The in vitro measurement of shear bond strength of the adhesive soft liner after 2 weeks of aging. 3. A comparison of debonding patterns. 4. An evaluation the Relation time of modified soft liner. The soft liner used in this study was commercially available as Coe-soft (GC America.IL.,USA), which is provided in forms of powder and liquid. This is a PMMA soft liner commonly used in dental clinics. The metal primer used in this study was 4-META containing primer packed in Meta fast denture base resin (Sun Medical Co., Osaka, Japan). The specimens were formed in a single lap joint desist which is useful for evaluating the apparent shear bond strength of adhesively bonded metal plate by tensile loading. Using the $20{\times}20mm$ transparent grid, percent area of adhesive soft liner remaining on the shear area was calculated to classify the debonding patterns. To evaluate the change of the initial flow of the modified adhesive soft liner, the gelation time was measured with an oscillating rheometer (Haake RS150W/ TC50, Haake Co., Germany). It was a stress control and parallel plate type with the diameter of 35mm. Conclusion. Within the conditions and limitations of this study, the following conclusions were drawn as follows. 1. There was significant increase of bond strength in the 5% 4-META, 10% 4-META containing groups and in the primer coated groups versus the control group(P<0.05). 2. After 2 weeks of aging, no significant increase in bond strength was found except for the group containing 10% 4-META (P<0.05). 3. The gelation times of the modified soft liner were 9.3 minutes for the 5% 4-META containing liner and 11.5 minutes for the 10% 4-META liner. 4. The debonding patterns of the 4-META containing group after 2 weeks of aging were similar to those of immediaely after preparation, but the debonding pattern of the primer group showed more adhesive failure after 2 weeks of aging.

유성기음반과 라디오방송을 통해 향유된 시조의 양상과 특징 (Communication and Enjoyment of Sijo through the Mass Media in the First Half of the 20th Century)

  • 박지애
    • 한국시조학회지:시조학논총
    • /
    • 제44권
    • /
    • pp.7-28
    • /
    • 2016
  • 이 글은 20세기 이후 새롭게 등장한 근대적 대중매체 중 유성기음반과 라디오 방송을 통해 소통되고 향유된 가곡창과 시조창의 실상을 객관적 자료를 통해 살피는 것을 목적으로 한다. 먼저 유성기음반으로 취입된 가곡 및 시조의 특징은 다음과 같다. 첫째, 가곡과 시조 유성기음반은 취입 초기부터 '고급문화의 향유'를 강조함으로써, 잡가 위주로 취입되던 당시의 전통노래 음반과의 변별성을 강조하였다. 둘째, 유성기음반 취입이 본격화되는 1920년대 중반까지만 하더라도 가곡창 위주로 음반 취입이 진행되었으며, 유성기음반이 대중화되는 1930년대 이후에는 가곡창보다는 시조창 위주로 음반이 취입되었다. 다음으로 라디오로 방송된 가곡 및 시조의 특징은 다음과 같다. 첫째, 라디오방송에서는 가곡 방송이 시조 방송에 비해 상대적으로 우세하였다. 둘째, 가곡 방송은 가곡창만으로 하나의 프로그램을 구성하여 방송하였으며, 시조는 1930년대 후반에 와서야 시조창만으로 방송 프로그램이 구성되었다. 당시 시조와 함께 방송된 노래 양식은 가창가사뿐만 아니라 긴잡가, 통속 민요에 이르기까지 다양하였다. 셋째, 시조 방송은 연행자와 방송 곡목에 따라 크게 세 시기로 구분할 수 있다. 라디오방송이 시작된 1926년부터 1932년까지는 19세기 연행문화의 연장에 가까운 시기라고 할 수 있다. 라디오가 대중적으로 보급되기 시작하는 1933년부터 936년까지는 기생들이 주도적으로 활동하며, 당시 대중적인 인기를 얻고 있던 잡가 및 통속민요와 시조창을 묶어 방송 레퍼토리로 구성한 시기이다. 1937년 이후는 이왕직아악부, 향제 가객들의 방송 진출 등 기녀 집단 일변도로 구연되던 방송 환경은 다변화되는 시기이다. 가곡과 시조는 1920년대와 30년대 초반까지만 하더라도 대중매체를 통한 노래 향유와 전승이라는 달라진 매체 환경에 적극적으로 대응한 것으로 파악된다. 빠른 악곡 위주의 음반 취입, 시조창과 잡가 및 통속민요를 하나의 방송 프로그램으로 편성한 것 등은 이러한 노력의 일환으로 볼 수 있다. 하지만 달라진 매체 환경에 맞추어서 새롭게 만들어진 신가요와 기존의 노랫말을 더욱 통속적으로 변화시킨 잡가와의 경쟁에서 가곡과 시조가 우위를 차지하기는 힘들 수밖에 없다. 이러한 노래 향유 환경의 변화 속에서 1930년대 중 후반에 이르면, 가곡과 시조 담당층은 오히려 전통적인 형태를 재현하는 방향으로 기존의 통속적인 노래 양식들과 변별되고자 하였다. 이왕직아악부의 음반 취입과 방송 참여, 지방 가객들의 진출, 남성 연행자들의 참여 등은 가곡과 시조의 향유문화를 다변화시켰을 뿐만 아니라, 통속적인 노래와의 '격조의 차이'를 더욱 분명하게 드러나게 하였다.

  • PDF