• Reproductive and Developmental Biology
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• v.36 no.1
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• pp.33-37
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• 2012

Differential capacity of the parthenogenetic embryonic stem cells (PESCs) is still under controversy and the mechanisms of its neural induction are yet poorly understood. Here we demonstrated neural lineage induction of PESCs by addition of insulin-like growth factor-2 (Igf2), which is an important factor for embryo organ development and a paternally expressed imprinting gene. Murine PESCs were aggregated to embryoid bodies (EBs) by suspension culture under the leukemia inhibitory factor-free condition for 4 days. To test the effect of exogenous Igf2, 30 ng/ml of Igf2 was supplemented to EBs induction medium. Then neural induction was carried out with serum-free medium containing insulin, transferrin, selenium, and fibronectin complex (ITSFn) for 12 days. Normal murine embryonic stem cells derived from fertilized embryos (ESCs) were used as the control group. Neural potential of differentiated PESCs and ESCs were analyzed by immunofluorescent labeling and real-time PCR assay (Nestin, neural progenitor marker; Tuj1, neuronal cell marker; GFAP, glial cell marker). The differentiated cells from both ESC and PESC showed heterogeneous population of Nestin, Tuj1, and GFAP positive cells. In terms of the level of gene expression, PESC showed 4 times higher level of GFAP expression than ESCs. After exposure to Igf2, the expression level of GFAP decreased both in derivatives of PESCs and ESCs. Interestingly, the expression level of $Tuj1$ increased only in ESCs, not in PESCs. The results show that IGF2 is a positive effector for suppressing over-expressed glial differentiation during neural induction of PESCs and for promoting neuronal differentiation of ESCs, while exogenous Igf2 could not accelerate the neuronal differentiation of PESCs. Although exogenous Igf2 promotes neuronal differentiation of normal ESCs, expression of endogenous $Igf2$ may be critical for initiating neuronal differentiation of pluripotent stem cells. The findings may contribute to understanding of the relationship between imprinting mechanism and neural differentiation and its application to neural tissue repair in the future.

• Korean Journal of Bronchoesophagology
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• v.8 no.1
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• pp.29-34
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• 2002

Background and Objectives : Sulfur dioxide gas is one of the major airborne Pollutants noxious to human in industrialized countries. The most vulnerable areas in the human respiratory system were the trachea and main bronchi and a gradient of decreasing damage was observed in the peripheral tracheobronchial tree. Induced functional alteration was increased mucosal permeability, and morphological changes were epithelial sloughing, intracellular edema, mitochondrial swelling, widened intercellular spaces, and ciliary cytoplamic extrusions. The laminins are a family of extracellular matrix glycoproteins localized in the basement membrane. Their primary role is cell-matrix attachment, but many additional biologic activities, including Promoting cell growth and migration, tumor growth and metastasis, wound repair, and graft survival, have been demonstrated. Materials and Methods : Histologic changes and expression of laminin in tracheal mucosa sacrificed at 1 day, 2 day, 3 day, 1 week, 2 weeks, and 3 weeks after continued SO2 exposure of 250 ppm for 30 minutes a day(to 7week) were studied in rats. In this study, mild immune reaction for laminin was noted at the apical cytoplasm of epithelial cells and basement membrane one day after a 7 week $SO_2$ exposure. The cilia and nucleoi of epithelial cells were normal and no immune reaction was noted in Goblet cells. The lamina propria of the tracheal tissue was infiltrated by monocytes and lymphocytes. Results : At 24 hours after exposure, all tracheal cells except Goblet cells revealed a mild immune reaction for laminin. No immune reactions were noted in the basement membrane. At 72 hours after exposure, mild or moderate immune reactions for laminin was seen in the tracheal cell cytoplasm. Irregular faint immune reaction for laminin was noted in the basement membrane. At 1 week after exposure, strong immune reaction for laminin was detected over all tracheal cells, and the basement membrane was seen clearly. At 2~3 weeks after exposure, strong immune reaction for laminin was seen in all tracheal epithelial cells except Goblet cells and a mild immune reaction was partly revealed in the basement membrane. Conclusion : Our study suggests that 502 produces histologic damage on the tracheal mucosa. Longer duration after exposure of $SO_2$ makes more progressive healing on the tracheal mucosa and increased immunoreactivity for laminin.

• Journal of Korean Society of Forest Science
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• v.86 no.1
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• pp.80-86
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• 1997

The objective of this study was to investigate how resistant poplar hybrid makes compensation to ozone stress. Growth, net assimilation rate and initial Rubisco activity were investigated. This study elucidates the physiological mechanisms associated with ozone sensitivity and resistance in 3 selected $F_2$ hybrids, a family originating from a cross between Populus trichocarpa${\times}$P. deltoides. Open-top chambers were used. Ozone concentrations varied from 90 to 115 ppb for 126 days, 6 to 9 hours in a day. This study tested the hypothesis that resistant poplar hybrid maintains the biomass production to ozone exposure via increased net assimilation rate and Rubisco activity. Growth, biomass, net assimilation rate and initial Rubisco activity were generally reduced by ozone treatment. In the tree parts, root under ozone stress was the most sensitive part. Reduced allocation of photosynthates to root growth might be due to increased respiratory demands for maintenance and repair of aboveground tissue damaged by ozone stress. Maintenance or increases remaining leaves in photosynthetic rates and Rubisco activity in resistant clone in response to ozone treatment were the results of biological compensation to ozone stress.

• Journal of Periodontal and Implant Science
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• v.32 no.1
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• pp.213-224
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• 2002

The ultimate goal of periodontal disease therapy is to promote the regeneration of lost periodontal tissue, there have been many attempts to develop a method to achieve this goal, but none of them was completely successful. The purpose of this study was to compare the effects of treatment using BBP(R) with control treated by only modified Widman flap. 22 intrabony defects from 12 patients with chronic periodontitis were used for this study, 10 sites of them were treated with BBP(R) as experimental group and 12 site were treated by only modified Widman flap as control group. Clinical parameters including probing depth, gingival recession, bone probing depth and loss of attachment were recorded at 6 months later, and the significance of the changes was statistically analyzed. The results are as follows : 1. Probing depth of control(${\triangle}2.7{\pm}1.3mm$) and experimental group(${\triangle}3.6{\pm}1.8mm$) weres reduced with statistically significance(P<0.05), but this changes were not different between the two experiment, control group with statistically significance. 2. Gingival recession showed statistically significant increase in control group(${\triangle}2.1{\pm}1.2mm$)(P<0.05), but not in experimental group(${\triangle}0.5{\pm}0.7mm$), and this changes were different between the two experiment, control group with statistically significance(P<0.05). 3. Bone probing depth showed statistically significant decrease in experimental group(${\triangle}2.9{\pm}1.0mm$)(P<0.05), but not in control group(${\triangle}1.1{\pm}1.4mm$), and this changes were different between the two experiment, control group with statistically significance(P<0.05). 4. Loss of attachment showed statistically significant decrease in experimental group(${\triangle}3.1{\pm}1.7mm$), but not in control group(${\triangle}0.6{\pm}1.2mm$), and this changes were different between the two experiment, control group with statistically significance(P<0.05) On the basis of these results, treatment using BBP(R) improves the probing depth, bone probing depth and loss of attachment in intrabony defects.

• Journal of the korean academy of Pediatric Dentistry
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• v.27 no.3
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• pp.388-393
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• 2000

Cleft lip and palate is one of the most common congenital defects in oro-maxillo-facial region. Because most patients undergo surgical repair in early life, the sagittal jaw relationships used to be deteriorated gradually from palate surgery up to adulthood. Also, the maxillary lateral incisor may be absent or atypical-shaped in the cleft site and may not erupt or erupt ectopically, so multidisciplinary dental cares are needed for cleft lip and palate patients. The effects of the cleft lip and alveolus seem to be limited to that part of the dentofacial complex that surrounds the cleft area. In the maxillary arch, the anterior part of the non cleft segment has a tendency to be rotated forward. On the other hand, the cleft segment has a tendency to rotated slightly medially ; hence, the tendency for canines to be edge-to-edge and sometimes in crossbite. Lip and alveolus surgery adequetely correct these problems, with little untoward effect on the skeletal maxillary-mandible relationships. In this report, the patient has a repaired lip and cleft alveolus on the left side with congenital missing on '62, '22, oronasal fistula, and skeletal class III malocclusion which is not affected by lip surgery. Dental treatments for this patient including orthodontic(space supervision, functional regulator in mixed dentition, fixed therapy in permanent dentition) and prosthodontic(removable obturator with key and keyway attachment and Konus crown) therapy were performed to improve the patient's functions and esthetics.

• Journal of Periodontal and Implant Science
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• v.37 no.4
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• pp.655-669
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• 2007

Reactive oxygen species (ROS) have been implicated in the pathogenesis of various diseases. And vitamin C has shown a protective effect for the tissues. The aim of this study was to evaluate the effects of $H_2O_2$ and ascorbic acid on matrix metalloproteinase-1 (MMP-1), tissue inhibitor of metalloproteinase (TIMP: TIMP-1, TIMP-2), Type 1 collagen, fibronectin, and PDLs22 level in human periodontal ligament fibroblasts (hPDLF) via reverse transcription-polymerase chain reaction (RT-PCR). hPDLF was obtained from a healthy periodontium and cultured in Dulbecco's modified Eagles's medium plus 10% fetal bone serum. The concentration of ascorbic acid in hPDLF was $50{\mu}g/ml$, and that of $H_2O_2$ in hPDLF was 0.03% and 0.00003%. Ascorbic acid only, $H_2O_2$ only and mixture of ascorbic acid and $H_2O_2$ were applied with hPDLF for 1-, 3-, and 30-min. respectively. The gene expression of MMP-1-, TIMP-1-, TIMP-2-, Type 1 collagen-, fibronectin-, and PDLs22-mRNA in hPDLF was analysed via RT-PCR. The results were as follows; 1. hPDLF in response to 30-min. incubation with 0.03% $H_2O_2$ did not show any gene expression. 2. In all the experimental groups, the gene expression of fibronectin mRNA showed the decreased tendency compared to control. 3. In all the experimental groups, the gene expression of TIMP-1 mRNA showed the tendency similar to control. 4. hPDLF in response to 30-min. incubation with 0.03% $H_2O_2$ and ascorbic acid increased mRNA induction for MMP-1. 5. In all the experimental groups, hPDLF increased mRNA induction for PDLs22, collagen type 1, and TIMP-2 compared to control. Within the limited experiments, $H_2O_2$ and ascorbic acid increased mRNA induction for PDLs22, collagen type 1, TIMP-2 in hPDLF. More research will be needed in order to confirm the relative importance of the different roles of ROS and antioxidants in hPDLF from a periodontal regeneration or repair standpoint.

• Journal of Microbiology and Biotechnology
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• v.26 no.6
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• pp.1140-1147
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• 2016

The plasma and serum of Crocodylus siamensis have previously been reported to exhibit potent antimicrobial, antioxidant, and anti-inflammatory activities. During wound healing, these biological properties play a crucial role for supporting the formation of new tissue around the injured skin in the recovery process. Thus, this study aimed to evaluate the wound healing properties of C. siamensis plasma and serum. The collected data demonstrate that crocodile plasma and serum were able to activate in vitro proliferation and migration of HaCaT, a human keratinocyte cell line, which represents an essential phase in the wound healing process. With respect to investigating cell migration, a scratch wound experiment was performed which revealed the ability of plasma and serum to decrease the gap of wounds in a dose-dependent manner. Consistent with the in vitro results, remarkably enhanced wound repair was also observed in a mouse excisional skin wound model after treatment with plasma or serum. The effects of C. siamensis plasma and serum on wound healing were further elucidated by treating wound infections by Staphylococcus aureus ATCC 25923 on mice skin coupled with a histological method. The results indicate that crocodile plasma and serum promote the prevention of wound infection and boost the re-epithelialization necessary for the formation of new skin. Therefore, this work represents the first study to demonstrate the efficiency of C. siamensis plasma and serum with respect to their wound healing properties and strongly supports the utilization of C. siamensis plasma and serum as therapeutic products for injured skin treatment.

• Journal of Veterinary Clinics
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• v.31 no.6
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• pp.523-526
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• 2014

Three dogs were admitted for repair of bone fracture. Case 1 (Maltese, 1.8 kg, intact female, 5-month-old) and case 2 (poodle, 3.0 kg, intact female, 6-month-old) had non-weight bearing lameness in the left pelvic limb, and case 3 (mixed, 3.3 kg, intact female, age unknown) had non-weight-bearing lameness in the left thoracic limb. On orthopedic examination, there was pain, crepitus, palpable instability and substantial soft tissue swelling on the affected side. No neurological deficits were identified. Radiographs revealed left proximal metaphyseal tibial and fibular fractures in cases 1 and 2, and left proximal metaphyseal radial and ulnar fractures in case 3. All cases had closed long-bone fractures with short juxta-articular fracture segments. Under fluoroscopic guidance, proper placement of the ring fixation elements was confirmed during surgery. Two or three rings were used to stabilize fractures with traditional circular external skeletal fixators (CESF). Postoperative radiographs showed acceptable alignment and apposition of the previously identified fracture. Time to radiographic union ranged from 5 to 14 weeks and there were no signs of implant failure or pin tract infection. Functional outcomes were excellent in all cases. CESF can be successfully used to reduce short juxta-articular fractures in which bone plates or external skeletal fixation cannot be applied.

• Nutritional Sciences
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• v.9 no.4
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• pp.233-239
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• 2006

Porous matrices of bioactive polymers such as polyglycolic acid (PGA) or polylactic acid (PLA) can be used as scaffolds in bone tissue growth during bone repair process. These polymers are highly porous and serve as a template for the growth and organization of new bone tissues. We evaluated the effect of PGA and PLA polymers on osteoblastic MC3T3-E1 cell extracellular mineralization. MC3T3-E1 cells were cultured in a time-dependent manner -1, 15, 25d as appropriate - for the period of bone formation stages in one of the five culture circumstances, such as normal osteogenic differentiation medium, PGA-plated, fetal bovine serum (FBS)-plated, PGA/FBS-coplated, and PLA-plated For the evaluation of bone formation, minerals (Ca, Mg, Mn) and alkaline phosphatase activity, a marker for osteoblast differentiation, were measured Alizarin Red staining was used for the measurement of extracellular matrix Ca deposit During the culture period, PGA-plated one was reabsorbed into the medium more easily and faster than the PLA-plated one. At day 15, at the middle stage of bone formation, cellular Ca and Mg levels showed higher tendency in PGA- or PLA-plated treatments compared to non-plated control and at day 25, at the early late stage of bone formation, all three cellular Ca, Mg or Mn levels showed higher tendency as in order of PGA-related treatments and PLA-plated treatments, compared to control even without significance. Medium Ca, Mg or Mn levels didn't show any consistent tendency. Cellular ALP activity was higher in the PGA- or PLA-plated treatments compare to normal osteogenic medium treatment PGA-plated and PGA/FBS-plated treatments showed better Ca deposits than other treatments by measurement of Alizarin Red staining, although PLA-plated treatment also showed reasonable Ca deposit. The results of the present study suggest that biodegradable material, PGA and also with less extent for PLA, can be used as a biomaterial for better extracellular matrix mineralization in osteoblastic MC3T3-E1 cells.

• Journal of Life Science
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• v.29 no.3
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• pp.382-393
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• 2019

Wound care is a health industry concern affecting millions worldwide. Recent increase in metabolic disorders such as diabetes comes with elevated risk of wound-based complications. Treatment and management of wounds are difficult practices due to complexity of the wound healing process. Conventional wound dressings and treatment applications only provide limited benefits which are mainly aimed to keep wound protected from external factors. To improve wound care, recent developments make biopolymers to be of high interest and importance to researchers and medical practitioners. Biopolymers are polymers or natural origin produced by living organisms. They are credited to be highly biocompatible and biodegradable. Currently, studies reported biopolymers to exhibit various health beneficial properties such as antimicrobial, anti-inflammatory, hemostatic, cell proliferative and angiogenic activities which are crucial for effective wound management. Several biopolymers, namely chitosan, cellulose, collagen, hyaluronic acid and alginic acid have been already investigated and applied as wound dressing agents. Different derivatives of biopolymers have also been developed by cross-linking with other molecules, grafting with other polymers, and loading with bioactive agents or drugs which showed promising results towards wound healing without any undesired outcome such as scarring and physiological abnormalities. In this review, current applications of common biopolymers in wound treatment industry are highlighted to be a guide for further applications and studies.