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      • KCI등재

        조기분만진통 임부와 만삭 전 조기양막파열 임부의 정맥혈장내 산화 스트레스 지표

        김윤하 ( Yoon Ha Kim ),노은지 ( Eun Ji Noh ),백주아 ( Ju A Back ),김종운 ( Jong Woon Kim ),송태복 ( Tae Bok Song ) 대한주산의학회 2015 Perinatology Vol.26 No.4

        목적: 조기분만진통 및 만삭 전 조기양막파열 임부의 정맥혈장내 산화능과 항산화능의 차이를 비교하고 산화 스트레스가 조기양막파열의 병태생리에 어떤 역할을 하는가를 규명하고자 하였다.방법: 75명의 임부를 대상으로 정맥혈을 채취하고 원심분리 후 혈장을 얻었다. (1) A군, 정상 임부 24명, (2) B군, 조기분만진통 임부 25명, (3) C군, 만삭 전 조기양막파열 임부 26명. thiobarbituric acid 반응을 이용하여 지질과산화물 농도를 측정하였고, 2,4-dinitrophenylhydrazine 방법을 이용하여 단백질의 carbonyl 기 함량을 측정하였으며, oxygen radical absorbance capacity assay (ORAC)로 총 항산화능을 측정하였다. Mann-Whitney U test, Kruskal Wallis test를 이용하여 분석하였다. 결과: B군과 C군의 정맥혈장내 지질과산화 치는 A군에 비해 의미있게 높았으며(B군: 4.59±0.30, C군: 5.40±0.22 vs. A군: 3.90±0.26 nmol/mg protein, P<0.05), C군의 정맥혈장내 지질과산화 치는 B군에 비해 의미있게 높았다. C군의 정맥혈장내 carbonyl기 함량은 A군에 비해 의미있게 높았으며(C군: 5.68±0.42 vs. A군: 5.43±0.41 nmol/mg protein, P<0.05), A군과 B군간의 carbonyl기 함량에는 차이가 없었다. 항산화능에 있어서는 B군과 C군이 A군에 비해 의미있게 낮았으며(B군: 117.91±0.48, C군: 111.68±1.23 vs. A군: 119.14±1.12 mM/mL, P<0.05), C군이 B군에 비해 의미있게 낮았다(P<0.05). 결론: 만삭 전 조기양막파열시 조기분만진통에 비해 정맥혈장에서 산화적 변화가 증가되어 있었으며 항산화능은 감소되어 있었다. 이는 조기양막파열시 산화적 스트레스가 증가되어 있을 가능성을 시사한다. Purpose: This study was performed to investigate the oxidation and antioxidation capacity in the maternalvenous plasma of preterm labor with intact membranes, and premature rupture of membranes (PPROM), andalso to evaluate their roles in the pathophysiology of PPROM. Methods: Seventy five women in the following categories had venous blood retrieved: (1) Group A, normal pregnancy (n=24). (2) Group B, preterm labor with intact membranes (n=25). (3) Group C, preterm premature rupture of membranes (n=26). Malondialdehyde (MDA) levels as a marker of lipid peroxidation by thiobarbituric acid reaction, protein carbonyl content by 2,4-dinitrophenylhydrazine reaction, and total antioxidant capacity by oxygen radical absorbance capacity assay (ORAC) were measured. Mann-Whitney U test, Kruskal-Wallis test were used for statistical analysis. Results: Lipid peroxide levels in the venous plasma of group B and C were significantly higher than those of group A (group B: 4.59±0.30, group C: 5.40±0.22 vs. group A: 3.90±0.26 nmol/mg protein, P<0.05). Lipid peroxide levels in the venous plasma of group C were significantly higher than those of group B (P<0.05). Protein carbonyl levels in the venous plasma of group C were significantly higher than those of group A (group C: 5.68±0.42 vs. group A: 5.43±0.41 nmol/mg protein, P<0.05). There was no significant difference of protein carbonyl levels in the venous plasma between group A and B. ORAC levels in the venous plasma of group B and C were significantly lower than those of group A (group B: 117.90±0.48, group C: 111.68±1.23 vs. group A: 119.14±1.12 mM/mL, P<0.05). ORAC levels in the venous plasma of group C were significantly lower than those of group B (P<0.05). Conclusion: In the blood of the women with preterm premature rupture of membranes, the lipid peroxidation was increased and the antioxidant capacity was decreased compared to women with normal pregnancy and preterm labor with intact membranes. These results suggest that oxidative stress was increased in preterm premature rupture of membranes.

      • KCI등재

        Effects of Resistance Training on Skeletal Muscle GLUT-4 Protein and LDH Isozyme Expression in Rats

        김연희(Yeon-Hee Kim),이상학(Sang-Hak Lee),김종오(Jong-Oh Kim),서태범(Tae-beom Seo),김영표(Young-Pyo Kim),백경아(Kyoung-A Back),윤진환(Jin-Hwan Yoon) 한국생명과학회 2011 생명과학회지 Vol.21 No.11

        본 연구는 7주령의 S·D계 흰쥐를 이용하여 12주 동안의 사다리 오르기 저항성 운동 수행 후 가자미근과 비복근 내 GLUT-4 발현량 및 LDH 동위효소들의 변화를 측정하여 당 대사 및 젖산 기전에 대한 연구로 다음과 같은 결론을 얻었다. 12주간의 사다리 오르기 저항성 운동은 체중감소에 효과적인 것으로 나타났으며, 가자미근 및 비복근 조직 GLUT-4 단백질 발현을 유의하게 증가시키는 것으로 나타났다. 또한 가자미근 및 비복근 조직 LDHA B-type 동위효소의 발현을 유의하게 증가시키는 것으로 나타났다. 본 연구의 결과를 종합해 볼 때 12주간의 저항성훈련은 체중의 감소와 골격근 내 GLUT-4의 증가 그리고 LDH A4 동위효소를 제외한 LDH B-type 동위효소의 증가와 같은 신체조성의 균형과 당대사능력 및 미토콘드리아의 기능 개선에 영향을 미치는 것으로 사료된다. 추후 연구에서는 휴식시간이나 운동 강도의 차이와 근형태별에 따른 유?무산소적 저항훈련 프로그램의 효과에 따른 다양한 연구가 실시되어야 할 것으로 생각된다. The purpose of the present study was to investigate the effect of climbing resistance training on GLUT-4 protein and LDH isozyme activities of the soleus and gastrocnemius muscles in rats. Each experimental group was randomly divided into a control group (n=6) and a resistance exercise (n=6) group. Sprague-Dawley rats were made to climb a 180 cm tower for 12 wk. Weight changes in the resistance exercise group were significantly higher than in the control group (p<0.05). GLUT-4 protein expression of the soleus and gastrocnemius muscles was significantly higher (p<0.05) in the resistance exercise group than in the control group. There was no difference in soleus tissue LDHA4 isozyme activity between the groups. In the case of other LDH isozyme, when compared with the control group, the resistance exercise group showed a significantly higher activity (p<0.05). LDHA4 activity of gastrocnemius muscle tissue was not different between the groups. However, the activity of the resistance exercise group of all the other LDH isozymes was significantly higher than that of the control group (p<0.05). In summary, based on the results of this study, over 12 weeks of resistance training, the total body weight of the rats was reduced and the GLUT-4 activity in the gastrocnemius and soleus muscles was increased. In addition, except for LDH A4 all of the other LDH isozymes activities were increased. These results suggest that climbing resistance training affects the balance of body composition, increases LDH B-type isoenzymes and glucose metabolism capacity, and improves mitochondrial function.

      • Protective effect of unilateral and bilateral ear plugs on noise-induced hearing loss: Functional and morphological evaluation in animal model

        Kim, D.-K.,Park, Y.,Back, S.-A.,Kim, H.L.,Park, H.E.,Park, K.-H.,Yeo, S.W.,Park, S.-N. NRN PUBLICATIONS 2014 Noise & health Vol.16 No.70

        The aim of the following study is to evaluate immediate protective effect of ear plug from noise morphologically and functionally. An 1-month aged 29 male C57BL/6 mice. Subjects were divided into four groups as normal control(G1), bilaterally plugged group (G2), unilaterally plugged group (G3) and noise control group (G4) and later 3 groups were exposed to 110 sound pressure level white noise for 60 min. Immediately after noise exposure, audiologic tests were performed and cochlear morphology and expression levels of a-synuclein in the cochlea were investigated. There were no functional changes in G2 and plugged ears of G3 after noise exposure, whereas unplugged ears of G3 and G4 showed significant hearing loss. In morphological study, there were a significant degeneration of the organ of Corti and mean number and diameter of efferent buttons, in unplugged ears of G3 and G4. Plugged ears of G3 also showed mild changes in morphological study. Reduction of a-synuclein was observed at the efferent terminals or cochlear extracts after noise exposure. The protective effect of ear plug on noise exposure was proven morphologically and functionally in the animal model of noise-induced hearing loss. Further study on cellular or ultrastructural level with ear plug will be needed to reveal more precise mechanism.

      • KCI등재

        A case of advanced-stage endometrial stromal sarcoma of the ovary arising from endometriosis

        ( Ju A Back ),( Myeong Gyune Choi ),( U Chul Ju ),( Woo Dae Kang ),( Seok Mo Kim ) 대한산부인과학회 2016 Obstetrics & Gynecology Science Vol.59 No.4

        Endometrial stromal sarcoma (ESS) is a rare malignancy. Development of extrauterine ESS form endometriosis is particularly rare. The majority of extrauterine ESS occurs in areas with preexisting endometriosis. The most common site is the ovary. We experienced a case of ESS of the ovary that arose from endometriosis with multiple disseminated lesions. This disease was managed by total abdominal hysterectomy, bilateral salpingo-oophorectomy, both pelvic lymph nodes dissection, omentectomy, and appendectomy followed by postoperative high-dose progesterone therapy. Here, we report this case with literature review.

      • KCI등재

        Ad libitum Pasture Feeding in Late Pregnancy Does Not Improve the Performance of Twin-bearing Ewes and Their Lambs

        R.A. Corner-Thomas,P.J. Back,P.R. Kenyon,R.E. Hickson,A.L. Ridler,K.J. Stafford,S.T. Morris 아세아·태평양축산학회 2015 Animal Bioscience Vol.28 No.3

        The present study evaluated the effect of controlled ryegrass-white clover herbage availability from day 128 until day 142 of pregnancy in comparison to unrestricted availability, on the performance of twin-bearing ewes of varying body condition score (BCS; 2.0, 2.5, or 3.0) and their lambs. It was hypothesised that under conditions of controlled herbage availability, the performance of lambs born to ewes with a greater BCS would be greater than those born to ewes with a lower BCS. During the period that the nutritional regimens were imposed, the pre- and post-grazing herbage masses of the Control regimen (1,070±69 and 801±30 kg dry matter [DM]/ha) were lower than the ad libitum regimen (1,784±69 and 1,333±33 kg DM/ha; p<0.05). The average herbage masses during lactation were 1,410±31 kg DM/ha. Nutritional regimen had no effect on ewe live weight, BCS and back fat depth or on lamb live weight, indices of colostrum uptake, maximal heat production, total litter weight weaned or survival to weaning (p>0.05). The difference in ewe BCSs and back fats observed among body condition groups was maintained throughout pregnancy (p<0.05). At weaning, ewes from the BCS2.0 group had lower BCS and live weight (2.4±0.2, 74.3±2.6 kg) than both the BCS2.5 (2.6±0.2, 78.6±2.4 kg) and BCS3.0 ewes (2.7±0.2, 79.0±2.6 kg; p<0.05), which did not differ (p>0.05). Ewe BCS group had no effect on lamb live weight at birth or weaning or on maximal heat production (p>0.05). Serum gamma glutamyl transferase concentrations of lambs born to BCS3.0 ewes were higher within 36 hours of birth than lambs born to BCS2.0 ewes and BCS2.5 ewes (51.8±1.9 vs 46.5±1.9 and 45.6±1.9 IU/mL, respectively [p<0.05]). There was, however, no effect of ewe body condition on lamb plasma glucose concentration (p>0.05). Lamb survival was the only lamb parameter that showed an interaction between ewe nutritional regimen and ewe BCS whereby survival of lambs born to BCS2.5 and BCS3.0 ewes differed but only within the Control nutritional regimen ewes (p<0.05). These results indicate farmers can provide twin-bearing ewes with pre- and post-grazing ryegrass-white clover herbage covers of approximately 1,100 and 800 kg DM/ha in late pregnancy, provided that herbage covers are 1400 in lactation, without affecting lamb performance to weaning. The present results also indicate that under these grazing conditions, there is little difference in ewe performance within the BCS range of 2.0 to 3.0 and therefore they do not need to be managed separately.

      • KCI등재

        Measurement of thermal expansion characteristic of root canal filling meterials : Gutta-percha and Resilon : Gutta-percha와 Resilon

        Jeon, Kyung-A,Lee, In-Bog,Bae, Kwang-Shik,Lee, Woo-Cheol,Back, Seung-Ho 대한치과보존학회 2006 Restorative Dentistry & Endodontics Vol.31 No.5

        근관충전재로 사용되는 gutta-percha의 대체재로서 Resilon이라는 bioactive glass와 약간의 방사선 불투과성성분을 포함하는 열가소성 고분자가 최근 소개되었다. 본 연구에서는 열연화 주입식 gutta-percha와 Resilon의 열팽창 특성을 측정하고 상호 비교하였다. 실험재료 중 gutta- percha 군으로는 Obtura, Diadent 그리고 Metadent 사의 gutta-percha를, Resilon으로 Pentron사의 Epiphany를 사용하였다. 열가압주입기인 Obtura Ⅱ에 4가지 재료를 넣고 설정온도를 100℃, 150℃, 180℃ 그리고 200℃로 바꾸어 가며 각 온도에 대해서, heating chamber 입구에서의 온도와 23 게이지와 20 게이지의 needle에서 사출되는 재료의 온도를 디지털 thermometer를 이용하여 측정하였다. 열팽창을 측정하기 위해 세라믹으로 내경 3 mm,외경 10 mm,길이 27mm의 원통형 주형을 제작하였고, 주형 안에 각 재료를 채워 넣은 후 양 끝을 세라믹 공이 (plunger)로 막았다. 이 시편을 dilatometer에 넣고 가열하여 25℃ 에서 75℃까지의 범위에서 열팽창 곡선을 얻었다. 온도에 따른 시편의 길이 변화로부터 각 재료의 열팽창 계수와 전체부피에 대한 팽창량을 계산하였다. 모든 재료에서 온도가 증가함에 따라 45℃ 이하에서는 재료의 부피변화가 거의 없었고, 45℃ 에서 55℃ 구간에서 급격히 팽창하였으며 그 이상의 온도에서는 완만한 부피의 증가를 보였다. 35℃에서 55℃사이에서의 부피의 변화는 재료들 사이에 통계적으로 유의한 차이가 없었으며 (p>0.05), 35℃에서 75℃사이의 부피의 변화는 Obtura사 gutta-percha가 Metadent사와 Diadent사의 gutta-percha에 비해 유의하게 작은 것으로 나타났다 (p<0.05). Epiphany는 gutta-percha 군들과 비슷한 열팽창을 보였다 (p>0.05). The purpose of this study was to evaluate the thermal expansion characteristics of injectable ther-moplasticized gutta-perchas and a Resilon. The materials investigated are Obtura gutta-percha, Diadent gutta-percha, E&Q Gutta-percha Bar and Epiphany (Resilon). The temperature at the heating chamber orifice of an Obtura Ⅱ syringe and the extruded gutta-percha from the tip of both 23- and 20-gauge needle was determined using a Digital thermometer. A cylindrical ceramic mold was fabricated for thermal expansion test, which was 27 mm long, with an internal bore diameter of 3 mm and an outer diameter of 10 mm. The mold was filled with each experi-mental material and barrel ends were closed with two ceramic plunger. The samples in ceramic molds were heated in a dilatometer over the temperature range from 25℃ to 75℃. From the change of specimen length as a function of temperature, the coefficients of thermal expansion were deter-mined. There was no statistical difference between four materials in the thermal expansion in the range from 35℃ to 55℃ (p>0.05). However, Obtura Gutta-percha showed smaller thermal expansion than Diadent and Metadent ones from 35℃ to 75℃ (p<0.05). The thermal expansion of Epiphany was similar to those of the other gutta-percha groups.

      • SCIESCOPUSKCI등재

        Ad libitum Pasture Feeding in Late Pregnancy Does Not Improve the Performance of Twin-bearing Ewes and Their Lambs

        Corner-Thomas, R.A.,Back, P.J.,Kenyon, P.R.,Hickson, R.E.,Ridler, A.L.,Stafford, K.J.,Morris, S.T. Asian Australasian Association of Animal Productio 2015 Animal Bioscience Vol.28 No.3

        The present study evaluated the effect of controlled ryegrass-white clover herbage availability from day 128 until day 142 of pregnancy in comparison to unrestricted availability, on the performance of twin-bearing ewes of varying body condition score (BCS; 2.0, 2.5, or 3.0) and their lambs. It was hypothesised that under conditions of controlled herbage availability, the performance of lambs born to ewes with a greater BCS would be greater than those born to ewes with a lower BCS. During the period that the nutritional regimens were imposed, the pre- and post-grazing herbage masses of the Control regimen ($1,070{\pm}69$ and $801{\pm}30$ kg dry matter [DM]/ha) were lower than the ad libitum regimen ($1,784{\pm}69$ and $1,333{\pm}33kg\;DM/ha$; p<0.05). The average herbage masses during lactation were $1,410{\pm}31kg\;DM/ha$. Nutritional regimen had no effect on ewe live weight, BCS and back fat depth or on lamb live weight, indices of colostrum uptake, maximal heat production, total litter weight weaned or survival to weaning (p>0.05). The difference in ewe BCSs and back fats observed among body condition groups was maintained throughout pregnancy (p<0.05). At weaning, ewes from the BCS2.0 group had lower BCS and live weight ($2.4{\pm}0.2$, $74.3{\pm}2.6kg$) than both the BCS2.5 ($2.6{\pm}0.2$, $78.6{\pm}2.4kg$) and BCS3.0 ewes ($2.7{\pm}0.2$, $79.0{\pm}2.6kg$; p<0.05), which did not differ (p>0.05). Ewe BCS group had no effect on lamb live weight at birth or weaning or on maximal heat production (p>0.05). Serum gamma glutamyl transferase concentrations of lambs born to BCS3.0 ewes were higher within 36 hours of birth than lambs born to BCS2.0 ewes and BCS2.5 ewes ($51.8{\pm}1.9$ vs $46.5{\pm}1.9$ and $45.6{\pm}1.9IU/mL$, respectively [p<0.05]). There was, however, no effect of ewe body condition on lamb plasma glucose concentration (p>0.05). Lamb survival was the only lamb parameter that showed an interaction between ewe nutritional regimen and ewe BCS whereby survival of lambs born to BCS2.5 and BCS3.0 ewes differed but only within the Control nutritional regimen ewes (p<0.05). These results indicate farmers can provide twin-bearing ewes with pre- and post-grazing ryegrass-white clover herbage covers of approximately 1,100 and 800 kg DM/ha in late pregnancy, provided that herbage covers are 1400 in lactation, without affecting lamb performance to weaning. The present results also indicate that under these grazing conditions, there is little difference in ewe performance within the BCS range of 2.0 to 3.0 and therefore they do not need to be managed separately.

      • The efficacy of 3rd generation cephalosporin plus metronidazole versus 3<sup>rd</sup> generation cephalosporin plus clarithromycin in perinatal outcomes for women with preterm premature rupture of membranes

        ( Jong Woon Kim ),( Yoon Ha Kim ),( A Ra Cho ),( Jong Ho Moon ),( Ju A Back ) 대한산부인과학회 2016 대한산부인과학회 학술대회 Vol.102 No.-

        목적: To compare perinatal outcomes of preterm premature of membranes treated with 3rd generation cephalosporin plus metronidazole (regimen A) versus 3rd generation cephalosporin plus clarithromycin (regimen B). 방법: A retrospective chart review compared perinatal outcomes in 186 patients with PROM <34 weeks receiving antibiotics regimen A (n=110) versus regimen B (n=76). Ninety-eight patients with PPROM between 25 and 32 weeks of gestation were chosen for comparing changes of the lipid peroxide, the protein carbonyl groups, ORAC values, and interleukin (IL)-6 levels in the maternal venous plasma (regimen A; n=54, regimen B; n=44). 결과: The rates of spontaneous preterm delivery within 2 days after initiation of antibiotic treatment were significantly lower in those receiving regimen B (4/76, 5.3%) than in those receiving regimen A (18/110, 16.4%) (p=0.022). There was no difference in the mean antibiotic-to-delivery interval (regimen A; 11.0 days, regimen B; 11.5 days). There is no difference in the presence of acute histologic chorioamnionitis and funisitis. There is no difference in the rate of neonatal outcomes including respiratory distress syndrome, bronchopulmonary dysplasia, sepsis, intra-ventricular hemorrhage, peri-ventricular leukomalacia, and necrotizing enterocolitis. There was no significant difference in lipid peroxide levels, protein carbonyl formation, ORAC, and IL-6 of the venous plasma before the antibiotics administration, day 3 and day 7 after the antibiotics administration between regimen A and B. 결론: Our results show that two antibiotics regimens may not effect on the latency period and improvement of neonatal outcomes. And they may not effect on the changes of oxidative stress. Although there was no significant difference in neonatal outcomes, 3rd generation cephalosporin plus clarithromycin regimen may have beneficial effect for short-term prolongation of pregnancy (up to 48 hours) to allow for the administration of antenatal steroids.

      • KCI등재후보

        Effect of Silicon Dioxide and Magnesium Oxide on the Printability, Degradability, Mechanical Strength and Bioactivity of 3D Printed Poly (Lactic Acid)-Tricalcium Phosphate Composite Scaffolds

        Harb Samarah V.,Kolanthai Elayaraja,Backes Eduardo H.,Beatrice Cesar A. G.,Pinto Leonardo A.,Nunes Ana Carolina C.,Selistre-de-Araújo Heloisa S.,Costa Lidiane C.,Seal Sudipta,Pessan Luiz Antonio 한국조직공학과 재생의학회 2024 조직공학과 재생의학 Vol.21 No.2

        Background: Poly (lactic acid) (PLA) is a biodegradable polyester that has been exploited for a variety of biomedical applications, including tissue engineering. The incorporation of β-tricalcium phosphate (TCP) into PLA has imparted bioactivity to the polymeric matrix. Methods: We have modified a 90%PLA-10%TCP composite with SiO2 and MgO (1, 5 and 10 wt%), separately, to further enhance the material bioactivity. Filaments were prepared by extrusion, and scaffolds were fabricated using 3D printing technology associated with fused filament fabrication. Results: The PLA-TCP-SiO2 composites presented similar structural, thermal, and rheological properties to control PLA and PLA-TCP. In contrast, the PLA-TCP-MgO composites displayed absence of crystallinity, lower polymeric molecular weight, accelerated degradation ratio, and decreased viscosity within the 3D printing shear rate range. SiO2 and MgO particles were homogeneously dispersed within the PLA and their incorporation increased the roughness and protein adsorption of the scaffold, compared to a PLA-TCP scaffold. This favorable surface modification promoted cell proliferation, suggesting that SiO2 and MgO may have potential for enhancing the bio-integration of scaffolds in tissue engineering applications. However, high loads of MgO accelerated the polymeric degradation, leading to an acid environment that imparted the composite biocompatibility. The presence of SiO2 stimulated mesenchymal stem cells differentiation towards osteoblast; enhancing extracellular matrix mineralization, alkaline phosphatase (ALP) activity, and bone-related genes expression. Conclusion: The PLA-10%TCP-10%SiO2 composite presented the most promising results, especially for bone tissue regeneration, due to its intense osteogenic behavior. PLA-10%TCP-10%SiO2 could be used as an alternative implant for bone tissue engineering application. Background: Poly (lactic acid) (PLA) is a biodegradable polyester that has been exploited for a variety of biomedical applications, including tissue engineering. The incorporation of β-tricalcium phosphate (TCP) into PLA has imparted bioactivity to the polymeric matrix. Methods: We have modified a 90%PLA-10%TCP composite with SiO2 and MgO (1, 5 and 10 wt%), separately, to further enhance the material bioactivity. Filaments were prepared by extrusion, and scaffolds were fabricated using 3D printing technology associated with fused filament fabrication. Results: The PLA-TCP-SiO2 composites presented similar structural, thermal, and rheological properties to control PLA and PLA-TCP. In contrast, the PLA-TCP-MgO composites displayed absence of crystallinity, lower polymeric molecular weight, accelerated degradation ratio, and decreased viscosity within the 3D printing shear rate range. SiO2 and MgO particles were homogeneously dispersed within the PLA and their incorporation increased the roughness and protein adsorption of the scaffold, compared to a PLA-TCP scaffold. This favorable surface modification promoted cell proliferation, suggesting that SiO2 and MgO may have potential for enhancing the bio-integration of scaffolds in tissue engineering applications. However, high loads of MgO accelerated the polymeric degradation, leading to an acid environment that imparted the composite biocompatibility. The presence of SiO2 stimulated mesenchymal stem cells differentiation towards osteoblast; enhancing extracellular matrix mineralization, alkaline phosphatase (ALP) activity, and bone-related genes expression. Conclusion: The PLA-10%TCP-10%SiO2 composite presented the most promising results, especially for bone tissue regeneration, due to its intense osteogenic behavior. PLA-10%TCP-10%SiO2 could be used as an alternative implant for bone tissue engineering application.

      • KCI등재후보

        화농성 근염과 감염성 대동맥류로 진행한 Klebsiella pneumoniae 간농양 1예

        김주형,김지은,백수영,구태연,이경아,정경희,김현철,김혜영,배현주 대한감염학회 2008 감염과 화학요법 Vol.40 No.6

        Klebsiella pneumonias causes pyogenic infections in various sites, with the risk of which increases in patients with diabetes mellitus. Recently, K. pneumoniae has emerged as a leading cause of pyogenie liver abscess, Primary liver abscess caused by K. pneumoniae in the absence of underlying hepatobiliary disease is commonly associated with metastatic infections such as endophthalmitis, meningitis, brain abscess and infection in other sites. We experienced a case of K. pneumonias liver abscess associated with septic metastatic lesions including pyomyositis and infected aneurysm of aorta. Despite the aggressive management with antibiotics, surgical pus drainage and aortic bypass graft, patient died of ventilator associated pneumonia and multiorgan failure. Our experience suggests that clinicians should be alert to septic metastatic infections when they treat a patient with K. pneumonias liver abscess.

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