• Title/Summary/Keyword: tissue morphology

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Ectopic expression of $ARR1{\Delta}DDK$ in tobacco: alteration of cell fate in root tip region and shoot organogenesis in cultured segments

  • Rashid, Syeda Zinia;Kyo, Masaharu
    • Plant Biotechnology Reports
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    • v.4 no.1
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    • pp.53-59
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    • 2010
  • A specific deleted version of ARABIDOPSIS RESPONSE REGULATOR1 (ARR1) lacking the signal receiver domain (1.152 amino acids)-coding sequence, referred to as $ARR1{\Delta}DDK$, was amplified using Arabidopsis thaliana cDNA prepared from adult leaves and transferred into the genome of Nicotiana tabacum cv. Samsun under the transcriptional control of a ${\beta}$-estradiol-inducible expression system. The ectopic expression of $ARR1{\Delta}DDK$ affected the morphology of transgenic seedlings and their segments in vitro. In the presence of an inducer, ${\beta}$-estradiol, ectopic expression of $ARR1{\Delta}DDK$ induced only the formation of soft, pseudo-bulbous tissue in the root tip region of intact seedlings, which appeared similar to callus generated on a hypocotyl segment in the presence of 2,4-D and 6-benzyladenine (BA), both at $1\;{\mu}M$. Those callus tissues on the root tip region could not generate shoots unless $1\;{\mu}M$ BA was supplied. In segment culture, ectopic expression of $ARR1{\Delta}DDK$ induced calluslike tissue around the cut-end of cotyledon and hypocotyl segments with occasional shoot formation, suggesting that the expression of $ARR1{\Delta}DDK$ could substitute for the effects of cytokinin on these segments. Additionally, treatment with only ${\beta}$-estradiol induced NtWUS, a WUS ortholog in tobacco, which was detected during the process of callus tissue formation in the root tip region and also in cotyledon or hypocotyl segments. These findings suggest that the NtWUS might be associated in the transdifferentiation process caused by the functional regulation of $ARR1{\Delta}DDK$ in transgenic tobacco seedlings.

Evaluation of Morphological Changes in Degenerative Cartilage Using 3-D Optical Coherence Tomography

  • Youn, Jong-In
    • Journal of the Optical Society of Korea
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    • v.12 no.2
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    • pp.98-102
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    • 2008
  • Optical Coherence Tomography (OCT) is an important noninvasive medical imaging technique that can reveal subsurface structures of biological tissue. OCT has demonstrated a good correlation with histology in sufficient resolution to identify morphological changes in articular cartilage to differentiate normal through progressive stages of degenerative joint disease. Current OCT systems provide individual cross-sectional images that are representative of the tissue directly under the scanning beam, but they may not fully demonstrate the degree of degeneration occurring within a region of a joint surface. For a full understanding of the nature and degree of cartilage degeneration within a joint, multiple OCT images must be obtained and an overall assessment of the joint surmised from multiple individual images. This study presents frequency domain three-dimensional (3-D) OCT imaging of degenerative joint cartilage extracted from bovine knees. The 3-D OCT imaging of articular cartilage enables the assembly of 126 individual, adjacent, rapid scanned OCT images into a full 3-D image representation of the tissue scanned, or these may be viewed in a progression of successive individual two-dimensional (2-D) OCT images arranged in 3-D orientation. A fiber-based frequency domain OCT system that provides cross-sectional images was used to acquire 126 successive adjacent images for a sample volume of $6{\times}3.2{\times}2.5\;mm^3$. The axial resolution was $8\;{\mu}m$ in air. The 3-D OCT was able to demonstrate surface topography and subsurface disruption of articular cartilage consistent with the gross image as well as with histological cross-sections of the specimen. The 3-D OCT volumetric imaging of articular cartilage provides an enhanced appreciation and better understanding of regional degenerative joint disease than may be realized by individual 2-D OCT sectional images.

A STUDY ON USEFULNESS OF THE REFERENCE LINE IN DIAGNOSIS OF THE FACIAL ASYMMETRY (안모비대칭의 진단용 기준선의 유용성에 관한 연구)

  • Ryu, Sung-Ho;Chang, Hyun-Ho
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.31 no.3
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    • pp.266-273
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    • 2005
  • Purpose: To assess the relationship between soft tissue reference line and hard tissue reference line using the standardized photographs and the posteroanterior cephalometric radiographs(P-A)in facial asymmetric patients and to compare the differences of angular measurement between normal group and asymmetry group. Methods: Normal group consisted of 44 persons with normal occlusion and normal facial morphology. Asymmetry group consisted of 90 patients with facial asymmetry. Standardized facial photographs and P-A were taken in all subjects. The horizontal reference lines were bipupillary line in photographs and latero-orbitale line in P-A respectively. The vertical reference line were the line from the midpoint of horizontal reference line perpendicularly. Angular measurement of otobasion canting, lip canting, nose deviation, chin deviation, and maxillary deviation were compared and analyzed in photographs. And angular measurement of mastoid canting, mandibular canting, nose deviation, chin deviation, and maxillary deviation were compared and analyzed in P-A. Results: 1. The variables of photographs and P-A were significantly related in the asymmetry group. 2. Significant differences between all variables except for PT2 and PA2 were shown in the asymmetry group and between PT1 and PA1, PT3 and PA3 in the normal group respectively. 3. Comparison measurement scores of angular difference between control group and experimental group concerning each variable showed significant difference except for PA1. Conclusions: Soft tissue components may not compensate for underlying skeletal imbalance in nose deviation and chin deviation. The horizontal reference lines in photographs were significant related with the P-A, but angular variables between the two studies show significant differences. Therefore, we do not recommend use photography in the assessment the facial asymmetry as complemented in the P-A.

Regulation of Skeletal Muscle Differentiation by Akt (Akt에 의한 근육세포의 분화 조절)

  • Woo, Dae-Han;Yun, Sung-Ji;Kim, Eun-Kyoung;Ha, Jung-Min;Shin, Hwa-Kyoung;Bae, Sun-Sik
    • Journal of Life Science
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    • v.22 no.4
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    • pp.447-455
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    • 2012
  • Akt plays an important role in a variety of cellular physiologies such as growth, proliferation, and differentiation. In skeletal muscle, Akt has been implicated in regulating regeneration, hypertrophy, and atrophy. In this study, the role of Akt has been examined during skeletal muscle differentiation. Culturing C2C12 myoblasts under low serum (1% horse serum) and high density converted cell morphology from a round shape to an elongated and multi-nucleated shape. Morphological changes were initiated from day 2 of differentiation. In addition, the expression of both myogenin G and myogenin D was elevated from day 2 of differentiation. Skeletal muscle differentiation was abolished by silencing Akt1 or Akt2, but was significantly enhanced by the over-expression of either Akt1 or Akt2. The activation of Akt was observed from day 2 of differentiation and disappeared after day 7. The expression of kruppel-like factor 4 was observed from day 6 of differentiation. Moreover, this expression was blocked in cells silencing either Akt1 or Akt2. In addition, the promoter activity of kruppel-like factor 4 was significantly reduced in cells silencing Akt1 or Akt2. These results suggest that Akt regulates skeletal muscle differentiation through the regulation of kruppel-like factor 4 expression.

Expression and Significance of TSGF, CEA and AFP in Patients Before and after Radical Surgery for Colon Cancer

  • Hu, Yi;Wang, Jing-Liang;Tao, Hai-Tao;Wu, Bai-Shou;Sun, Jin;Cheng, Yao;Dong, Wei-Wei;Li, Rui-Xin
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.6
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    • pp.3877-3880
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    • 2013
  • Objective: To explore the expression and significance of tumor specific growth factor (TSGF), carcinoembryonic antigen (CEA) and alpha fetoprotein (AFP) in cancer tissue and serum of patients with colon cancer. Materials and Methods: Radical surgery for colon cancer was performed on 43 patients with laparoscopu under conditions of general anesthesia. The Elisa method was used to detect the levels of serum TSGF, CEA and AFP before and after radical operation, and cancer tissue underwent TSGF, CEA and AFP immunohistochemistry staining after laparoscopic surgery. The decreased conditions of serum TSGF, CEA and AFP in patients with colon cancer at different levels of differentiation and clinical stagings were analyzed, and the relationships of expression rates between histological types, colon cancer morphology, lymph node metastasis and TSGF, CEA as well as AFP in cancer tissue were assessed. Results: Compared with before radical surgery, the levels of serum TSGF, CEA and AFP decreased notably in patients after operations (p<0.01). The decreased degree of TSGF and CEA was the largest in patients with poorly differentiated cancer tissue (p<0.01), while that of AFP was noted in patients with moderately differentiated cancer tissue (p<0.01). The decreased degree of TSGF and AFP was the largest in patients at phase Dukes A (p<0.01), while that of CEA in patients at phase Dukes C (p<0.01). There were no significant differences among the positive expression rates of TSGF, CEA and AFP with different histological types and colon cancer morphologies (p>0.05). The positive expression rates of TSGF and CEA in patients with lymph node metastasis were significantly higher than those without lymph node metastasis (p<0.01). Conclusions: TSGF, CEA and AFP can be used to evaluate the effect of radical operation for colon cancer, and the changed levels of different markers are associated with tumor differentiation, clinical stating and presence or absence of lymph node metastasis.

Characterization of Low-phosphorus Tolerance in an Anthocyanin-deficient Lycopersicon esculentum by tissue culture (조직 배양을 이용한 안토시아닌 결핍 돌연변이 토마토의 저인 내성 평가)

  • Lee, Dong-Hee;Bae, Gong-Young;Park, So-Hong
    • Korean Journal of Environmental Agriculture
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    • v.18 no.2
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    • pp.174-178
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    • 1999
  • An anthocyanin-deficient tomato (Lycopersicon esculentum Mill.) strain, H957, shows an unusual tolerance to low phosphorus (P). To investigate whether the tolerance originates from a tissue/cellular strength, plant tissue culture procedure was employed which facilitate to characterize the tolerance independent of morphological features. The tolerance was analyzed by comparing H957 against H883, its maternal wild type, while each explant was co-cultured on minimal P media. Comparisons were made in fresh weight, dry weight, callus and shoot formation, mineral contents, and P utilization ratios at $0-400{\cdot}\bar{I}MP$, . Growth of the two strains was severely impaired at 0 and $12.5{\cdot}\bar{I}MP.\;At\;25-200{\cdot}\bar{I}MP$, however, H957 consistently showed a greater fresh and dry weight than H883. Shoot onset of H957 was less delayed than H883 compared to optimal P conditions. H957 tissue contains an overall lower P concentration than H883. These observations indicate that H957 may tolerate to low P by its tissue or cellular strength in P utilization side from its morphology.

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Chondrogenic Differentiation of Human Mesenchymal Stem Cells on a Patterned Polymer Surface (패턴된 폴리머를 이용한 중간엽줄기세포의 연골 분화)

  • Heo, June Seok
    • Korean Journal of Clinical Laboratory Science
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    • v.47 no.3
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    • pp.117-124
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    • 2015
  • Mesenchymal stem cells (MSCs) are an attractive tool in tissue engineering as they have the required potential to treat injured articular cartilage. UV-exposed DTOPV (S-triazine bridged p-phenylene vinylene) is a biocompatible and fluorescent polymer with a hydrophilic surface. Previous studies have demonstrated that the surface wettability and hydrophilicity play critical roles in regulating cell adhesion and proliferation. The objective of this study was to improve the potential of in vitro MSC differentiation into Chondrocytes using DTOPV. MSCs were cultured on two different substrates: (1) tissue culture polystyrene (TCPS) as a reference and (2) UV-exposed and patterned DTOPV films. Chondrogenesis of MSCs was induced for two weeks on TCPS and DTOPV in the presence of an induction medium containing transforming growth factor (TGF)-${\beta}3$. Interestingly, the MSCs on TCPS adhered and spread, while those on DTOPV tended to form aggregates within several days. The cells cultured on DTOPV for two weeks had a round morphology, with stronger Safranine O staining of the extracellular matrix than that of the cells cultured on TCPS. Also, Type II collagen gene was significantly expressed in cells induced on DTOPV. These results indicate that chondrogenic differentiation of MSCs proceeds more rapidly on DTOPV than on TCPS. Therefore, in cartilage tissue engineering, DTOPV could be used to induce effective chondrogenic differentiation of MSCs.

Effects of histochemical staining in microwave-irradiated tissues (마이크로파 처리 고정 조직의 조직염색 효과)

  • Lee, Yoon-Jin;Lee, Sang-Han
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.8
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    • pp.417-424
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    • 2019
  • Despite its superior ability to show distinct cellular morphology and for long-term storage, conventional tissue fixation by formalin has many drawback, including slower fixation, the exposure to harmful chemicals and extensive protein modification. Herein, we assessed the effects of rapid microwave-assisted tissue fixation on histological examination and on protein integrity by comparing these microwave irradiation fixated tissues with the formalin-fixed tissues. One of the paired mouse tissues (liver and kidney) was fixed in formalin and the other was fixed by using microwave irradiation in phosphate buffered saline. Each slide from the paraffin-embedded tissues was examined by H & E staining for the adequacy of fixation and by immunohistochemical staining for antigenicity in a blinded fashion. Evaluation of protein recovery and the protein quality from the fixed tissues were analyzed by the BCA method and Western blotting, respectively. The results from H & E staining and immunohistochemical staining showed that the sections obtained from microwave-fixed tissues under our experimental conditions were comparable to those of the formalin-fixed tissues except for the integrity of RBCs. Furthermore, proteins were effectively extracted from the microwave-fixed tissues with acceptable preservation of the proteins' quality. Taken together, this microwave-assisted tissue processing yields a quick fixation and better protein recovery in higher amounts, as well as the adequacy of fixation and the antigenicity being comparable to formalin-fixed tissues, and this all suggests that this new fixation technique can be applied in an environment where rapid tissue fixation is required.

Natural Tooth Form Zirconia Implant Based on Anatomical Morphology (임상가를 위한 특집 2 - 형태 해부학적 특징을 바탕으로 한 자연치형 지르코니아 임플란트)

  • Park, Young-Seok;Lee, Seung-Pyo
    • The Journal of the Korean dental association
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    • v.52 no.9
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    • pp.541-549
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    • 2014
  • The restorative treatment using titanium implants has become a standard procedures in everyday clinical practice. However, there are several concerns about the use of titanium as a materials. Above all, the grayish metal color provokes esthetic problems when the soft tissue around the implants is not optimal. Recently, zirconia has been emerging as an alternative to titanium due to its white color and superior physicochemical properties. In this paper, the current findings about zirconia implants was reviewed based on the results from animal and clinical experiments. In addition, the immediate implantation protocols using the natural tooth form zirconia implants was introduced as a novel procedures and future perspectives were discussed.

Characteristics and clinical meanings of the implant with a sloped marginal configuration (경사진 상부 형태(sloped marginal configuration)를 가진 임플란트의 특징과 임상적 의미)

  • Kim, Taehyung
    • The Journal of the Korean dental association
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    • v.54 no.5
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    • pp.328-341
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    • 2016
  • An overall reduction in the horizontal and vertical dimensions occurs following tooth extraction and the resorption of the buccal part of the ridge is more pronounced than the lingual part. Thus, the resulting morphology of the healed alveolar ridge is often presenting with a discrepancy in bone height between the buccal and lingual aspects of the ridge. The implant with a sloped marginal configuration that is designed to match the sloped contour of the alveolar ridge provides the opportunity to maintain the buccal-lingual bone discrepancy and soft tissue around the implant. This paper introduces the OsseoSpeed TX Profile implants with sloped marginal configuration and explains the characteristics and clinical meanings of those implants.

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