• 대한의용생체공학회:의공학회지
• /
• 제14권1호
• /
• pp.81-88
• /
• 1993

This paper is the study of the reflectance of light from biological tissue for red and Infrared wavelengths and relates the acquired reflectance data to expected physiological changes within the skin and muscle layers associated with heat and exercise. The instrument was disigned to collect data from the calf muscle in human subjects with probe located at the surface of skin. Rapid data acquisition method allowed monitoring of rapid changes in reflecttance due to a stimulus. This study demonstrates that changes in O2 saturation and blood fractional volume expected within the dermis and muscle layers were asserted by examining the slopes of the plotted index for heat and exercise. The results presented in thls study support the claim that reflectance can separately discriminate between changes of blood volume and oxygenation in muscle and in skin. The data demonstrate the ability to measure consistent changes In tissue optical properties during exercise and heat.

• Journal of Periodontal and Implant Science
• /
• 제24권3호
• /
• pp.607-617
• /
• 1994

To determine the effect of tenascin on forming periodontal pocket and pseudopocket, the ginival tissues were surgically obtained from the patients with adult periodontitis(10) and non-inflammatory phenytoin-associated gingival hyperplasia(5). The excised tissue specimens were fixed in neutral formalin for $6{\sim}24$ hours, embedded with paraffin, sectioned at 4-6m in thickness, mounted on glass slides coated with 3-aminopropyltriethoxysilane(Sigma Chemical Co., St. Louis, MO, U.SA.) and immunohistochemically processed by Avidin-Biotin peroxidase complex method for the localization of tenascin, using monoclonal mouse anti-human tenascin antiboday(Chemicon-International Inc., Temecula, CA, U.S.A., 1: 5,000) as the primary antibody. Regardless of periodontal pocket and pseudopocket, tenascin was localized along the connective tissue subjacent to basement membrane of gingival epithelium, and strong positive reactivity was obviously noted in the papillary projections of gingival connective tissue. The results suggest that tenascin may affect the development of papillary projections and the proliferation of epithelial cells.

• BMB Reports
• /
• 제51권10호
• /
• pp.493-499
• /
• 2018

Cellular senescence is a state of permanent cell-cycle arrest triggered by different internal and external stimuli. This phenomenon is considered to be both beneficial and detrimental depending on the cell types and biological contexts. During normal embryonic development and after tissue injury, cellular senescence is critical for tissue remodeling. In addition, this process is useful for arresting growth of tumor cells, particularly during early onset of tumorigenesis. However, accumulation of senescent cells decreases tissue regenerative capabilities and induces inflammation, which is responsible for cancer and organismal aging. Therefore cellular senescence has to be tightly regulated, and dysregulation might lead to the aging and human diseases. Among many regulators of cellular senescence, in this review, I will focus on microRNAs, small non-coding RNAs playing critical roles in diverse biological events including cellular senescence.

• 대한의용생체공학회:의공학회지
• /
• 제11권2호
• /
• pp.227-232
• /
• 1990

As a part of the study on ultrasonic tissue characterization, conventional ultrasonic imaging system is interfaced to the personal computer to acquire raw ultrasonic signal. One approach for tissue charaterization is performed using the attenuation map to the conventional images and the resulting attenuation map images are compared and inspected inside the region of interest from the viewpoint of pattern analysis. Currently, these methods are applied and modified to effectively find out the differences between the normal control and the patients with liver cirrhosis.

• 한국식물학회:학술대회논문집
• /
• 한국식물학회 1999년도 제13회 식물생명공학심포지움 New Approaches to Understand Gene Function in Plants and Application to Plant Biotechnology
• /
• pp.1-9
• /
• 1999

Plant biotechnology including plant tissue culture is the most important science to rescue human beings from the crisis of biosphere of the earth which they will face in the 21st century. Global area other than Asia of trangenic crops increased more than 16 times from 1996 to 1998. In Asian countries, micropropagation using tissue culture techniques has been well developed and has contributed to agricultural production. Although researches on levels of laboratory and test field trial of transgenic crops have been performed actively in some Asian countries, areas of growing transgenic crops are still small in Asia countries except in China. In this paper, the status of plant biotechnology in global and Asian countries are reviewed and the future prospect of plant biotechnology in Asia and roles of Korean and Japanese plant scientists in it are discussed.

• The Journal of the Acoustical Society of Korea
• /
• 제29권1E호
• /
• pp.1-10
• /
• 2010

The difference in echogenicity between cancerous and normal tissues is not quite distinguishable in ultrasound B-mode imaging. However, tumor or cancer in breast or prostate tends to be stiffer than the surrounding normal tissue. Thus, imaging the stiffness contrast between the two different tissue types is helpful for quantitative diagnosis, and such a method of imaging the elasticity of human tissue is collectively referred to as ultrasound elasticity imaging. Recently, elasticity imaging has established itself as an effective diagnostic modality in addition to ultrasound B-mode imaging. The purpose of this paper is to present various elasticity imaging methods that have been reported up to now and to describe their principles of operation and characteristics.

• 대한의용생체공학회:의공학회지
• /
• 제15권3호
• /
• pp.265-274
• /
• 1994

This paper proposes a method of noninvasive reflectance light to measure the blood fractional volume (Vb) and oxygen saturation ($SO_2$) of biological tissue. We chose the red light of 660nm and infrared light of 880nm. In Vivo reflectance data were obtained by the physiological changes front the surface of the skin over the calf in human subject. The reflected light intensity from different layers within a biological tissue was measured by specially designed reflectometer to apply photon path diffusion model. The collected data represent the changes of blood (ractional volume and oxygen saturation at each reflected light wavelengths. The data evaluation was assessed by examining the slopes of the plotted indices for the changes in oxygen saturation and blood (ractional volume. The results presented in this paper claim that light reflectance can separately discriminate the change of blood volume and that of oxygenation in muscle and also in skin.

• Molecules and Cells
• /
• 제45권6호
• /
• pp.353-361
• /
• 2022

Chronic rhinosinusitis (CRS) is a multifactorial, heterogeneous disease characterized by persistent inflammation of the sinonasal mucosa and tissue remodeling, which can include basal/progenitor cell hyperplasia, goblet cell hyperplasia, squamous cell metaplasia, loss or dysfunction of ciliated cells, and increased matrix deposition. Repeated injuries can stimulate airway epithelial cells to produce inflammatory mediators that activate epithelial cells, immune cells, or the epithelial-mesenchymal trophic unit. This persistent inflammation can consequently induce aberrant tissue remodeling. However, the molecular mechanisms driving disease within the different molecular CRS subtypes remain inadequately characterized. Numerous secreted and cell surface proteins relevant to airway inflammation and remodeling are initially synthesized as inactive precursor proteins, including growth/differentiation factors and their associated receptors, enzymes, adhesion molecules, neuropeptides, and peptide hormones. Therefore, these precursor proteins require post-translational cleavage by proprotein convertases (PCs) to become fully functional. In this review, we summarize the roles of PCs in CRS-associated tissue remodeling and discuss the therapeutic potential of targeting PCs for CRS treatment.

• 분석과학
• /
• 제36권5호
• /
• pp.224-235
• /
• 2023

An analytical method was developed for the determination of phenol (P) and the seven substituted phenols in water samples and fish tissue samples collected from three streams located in eastern Gangwon State in spring and summer. The phenols were extracted and then derivatized to phenyl acetates using acetic anhydride. The derivatives were subsequently identified and quantified using gas chromatography coupled with mass spectrometry. P and 4-nitrophenol (4NP) were found at relatively high levels in water, ranging from below the method detection limit (MDL) to 3.32 ㎍/L and from < MDL to 4.91 ㎍/L, respectively. P and 4NP were also the dominant compounds in the fish tissue, ranging from < MDL to 407 ㎍/kg and from < MDL to 870 ㎍/kg, respectively. Phenol concentrations were significantly higher in spring than in summer. The ecological risk quotient calculated for P was higher than 4NP but not high enough to pose any risk of adverse effects to fish health.

• 한국정보통신학회논문지
• /
• 제10권8호
• /
• pp.1347-1351
• /
• 2006

초고주파 방사파 측정(microwave radiometry) 기술은 인체내부를 뚫지 않고 인체내부의 온도를 측정할 수 있는 기술로서 인체 내부의 질병이나 비정상을 조기에 진단할 수 있는 기술이다. 본 논문에서는 인체 방사파 신호를 측정하는 안테나로서 원형루프를 가진 다이폴형 안테나를 시뮬레이션하고 측정했다. 측정 결과는 $S11\leq-10dB$에 대해 $130%(0.8\sim3.8GHz)$의 초광대역 특성을 가짐으로써 다양한 질병을 가지는 인체조직의 위치와 크기를 검출하는데 적합하다고 할 수 있다.