• The Journal of the Acoustical Society of Korea
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• v.9 no.6
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• pp.5-13
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• 1990

본 논문에서는 16Kbps 및 32 Kbps 전송속도에서 ADM의 음질을 개선하기 위하여 두 가지 방 식을 적용한다. 첫째로, 고차 예측기 또는 적응 예측기를 ADM에 활용한다. ADM의 경우에 2차 또는 3 차 예측기를 사용하면 16Kbps 전송속도에서는 별로 개선이 없지만 32Kbps 전송속도에서는 SQNR\sub SEG\척도로 약 3-4dB의 상당한 이득이 얻어진다. 또한 ADM에 적응 예측기를 활용하면 최대 성능은 SZNR\sub SEG\ dir 2dB 정도 개선되지만 양자화 잡음의 축적 때문에 동작 범위가 매우 좁아진다. 둘 째로, 지연 결정 방식을 ADM에 이용한다. 지연 결정 방식을 2차 예측기를 갖고 있는 ADM에 적용하면 약 2dB 정도 개선되지만 양자화 잡음의 축적 때문에 동작 범위가 매우 좁아진다. 둘째로 지연 결정 방 식을 ADM 에 이용한다. 지연 결정 방식을 2차 예측기를 갖고 있는 ADM에 적용하면 1차 예측기를 갖 고 있는 ADMDP 적용했을 때 보다 16또는 32Kbps일 때 SQNR\sub SEG\척도로 재래의 ADM 보다 약 5dB 정도의 성능 개선이 얻어진다.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.6
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• pp.2619-2623
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• 2014

Aim: To investigate signaling pathways for reversal of EGF-mediated multi-drug resistance (MDR) in hepatocellular carcinoma (HCC) models. Materials and Methods: HCC MDR cell strain HepG2/adriamycin (ADM) and SMMC7721/ADM models were established using a method of exposure to medium with ADM between low and high concentration with gradually increasing concentration. Drug sensitivity and reversal of multi-drug resistance by EGF were determined and the cell cycle distribution and apoptosis were analyzed by flow cytometry. Phosphorylation of ERK1, ERK2, ERK5 and expression of Bim were detected by Western blotting. Results: The results showed that HepG2/ADM and SMMC7721/ADM cells were resistant not only to ADM, but also to multiple anticancer drugs. When used alone, EGF had no anti-tumor activity in HepG2/ADM and SMMC7721/ADM cells in vitro, while it increased the cytotoxicity of ADM. EGF induced cell apoptosis and G0/G1 phase cell cycle arrest in HepG2/ADM And SMMC7721/ADM cells, while enhancing activity of p-ERKs and up-regulated expression of BimEL. Conclusions: EGF might enhance the chemosensitivity of HepG2/ADM and SMMC7721/ADM cells via up-regulating p-ERKs and BimEL protein.

• Journal of Periodontal and Implant Science
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• v.37 no.3
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• pp.511-522
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• 2007

Introduction : The purpose of this study was to evaluate the possibility of the acellular dermal matrix (ADM) as a barrier membrane for bone regeneration, and to evaluate the osteogenic effect of ADM as a carrier system for rhBMP-2 in the rat calvarial defect model. Materials and Methods: An 8-mm, calvarial, critical-size osteotomy defect was created in each of 60 male Spraque-Dawley rats(weight $250{\sim}300g$). Three groups of 20 animals, each received either rhBMP-2(0.025mg/ml) in an ADM carrier, ADM only, or negative surgical control. And each group was divided into 2- and 8-weeks healing intervals. The groups were evaluated by histologic and histomorphometric parameters(10 animals/group/healing intervals). Data were expressed as $means{\pm}standard$ deviations($m{\pm}SD$). Comparisons between experimental and control groups were made using two-way ANOVA and post hoc t-test. Comparisons between 2 weeks and 8 weeks were made using paired t-test. The level of statistical difference was defined as P< 0.05. Results : The ADM group and rhBMP-2/ADM group results in enhanced local bone formation in the rat calvarial defect at both 2 and 8 weeks. The amount of defect closure and new bone formation were significantly greater in the rhBMP-2/ADM group relative to ADM group(P<0.05). At 8 weeks, the majority of ADM in the defect was contracted, and integrated with surrounding host tissues. In addition, host cell infiltration and neovascularization of the ADM in the absence of an inflammatory response were observed, and the newly formed bone around ADM showed a continuous remodeling and consolidation. Conclusion : The results of the present study indicated that ADM may be used as a barrier membrane for bone regeneration and that may be employed as a delivery system for BMPs.

• BMB Reports
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• v.34 no.1
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• pp.66-72
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• 2001

To investigate the mechanism of adriamycin (ADM) resistance in the ADM resistant subline PC-14/ADM, we examined the expressions of p-glycoprotein (P-gp), topoisomerase I (Topo I) and II (Topo II), glutathione-S-transferases (GSTs), tissue transglutaminase (t-TG), epidermal growth factor receptor (EGFR), and E-cadherin and the activity of superoxide dismutase (SOD) in PC-14 and PC-14/ADM cells. There was no change in the cellular levels of P-gp, Topo I, Topo II, and the two isoforms of GSTs. However, SOD activity in PC-14/ADM cells was 2.38 fold higher than that in PC-14 cells. A marked induction of the t-TG expression was also observed in PC-14/ADM cells. In addition to those changes, expressions of EGFR and E-cadherin were down regulated in PC-14/ADM cells. Therefore, molecular modifications such as an increase in SOD activity, induction of the t-TG expression, and down regulation of EGFR and E-cadherin expressions may play important roles in PC-14/ADM cells during the development of ADM resistance.

• Archives of Plastic Surgery
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• v.43 no.6
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• pp.523-528
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• 2016

Background The use of acellular dermal matrix (ADM) in implant-based immediate breast reconstruction has been increasing. The current ADMs available for breast reconstruction are offered as aseptic or sterile. No published studies have compared aseptic and sterile ADM in implant-based immediate breast reconstruction. The authors performed a retrospective study to evaluate the outcomes of aseptic versus sterile ADM in implant-based immediate breast reconstruction. Methods Implant-based immediate breast reconstructions with ADM conducted between April 2013 and January 2016 were included. The patients were divided into 2 groups: the aseptic ADM (AlloDerm) group and the sterile ADM (MegaDerm) group. Archived records were reviewed for demographic data and postoperative complication types and frequencies. The complications included were infection, flap necrosis, capsular contracture, seroma, hematoma, and explantation for any cause. Results Twenty patients were reconstructed with aseptic ADM, and 68 patients with sterile ADM. Rates of infection (15.0% vs. 10.3%), flap necrosis (5.0% vs. 7.4%), capsular contracture (20.0% vs. 14.7%), seroma (10.0% vs. 14.7%), hematoma (0% vs. 1.5%), and explantation (10.0% vs. 8.8%) were not significantly different in the 2 groups. Conclusions Sterile ADM did not provide better results regarding infectious complications than aseptic ADM in implant-based immediate breast reconstruction.

• Archives of Plastic Surgery
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• v.46 no.1
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• pp.34-38
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• 2019

Background Acellular dermal matrices (ADMs) have recently become widely used in breast reconstruction, but the correlation between the final expander volume and the surface area of the ADM is not well understood. In this study, the expansion of the surface area of ADM and the expander volume was studied retrospectively in cases of acellular dermis-assisted tissue expander breast reconstruction. Methods Twenty cases of immediate breast reconstruction using an ADM-assisted tissue expander from January 2015 to December 2015 were evaluated. In all 20 cases, CGCryoDerm was used as the matrix, with a thickness of 1-3 mm. No slit incisions were made. Finally, the proportional increase in the area of the fully expanded ADM was compared to that of the tissue expander volume. Results The proportional increase in the ADM surface area was calculated to be from 1.1 to 2.46, with a mean value of 1.7. Additionally, under the assumption that the expander had a spherical shape, the increase in its radius (the cube root of its volume) was assessed. The range of the proportional increase in the expander radius was 1.1 to 2.24, with a mean value of 1.66. The proportional increase in the radius of the expanded ADM surface area ranged from 1.04 to 1.34, with a mean ratio of 1.28. Conclusions The results of this study confirmed that the ADM expanded when the tissue expander was inflated. However, the ADM expanded to a lesser extent than the tissue expander, indicating that the muscle and other tissues expanded more than the ADM when the tissue expander was inflated.

• Archives of Pharmacal Research
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• v.16 no.2
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• pp.129-133
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• 1993

Temperature sensitive liposomes(TSL) containing adriamycin (ADM) and cytarabine (Ara-C) were prepared. ADM and Ara-C were selected as model compounds of amphiphilic and hydrophilic drug, respectively. Encapsulation efficiency of ADM entrapped into TSL was about twice greater than that of Ara-C. It might be due to different polarity of the drug, Lipid compositions of TSL had no effect on the encapsulation efficiency of drugs. Thermal behavior of TSL using a differential scanning calorimetry (DSC) was also investigated. Phase transition of TSL using a differential scanning calorimetry (DSC) was also investigated. Phase transition temperature $(T_c)$ of TSL was dependent on the lipid compositions of TSL ADM broadened thermogram of TSL but Ara-C did not. However, $T_c$ of TSL was not changed by any drug. Release rate of drugs was highly dependent on temperature. The release profile of ADM was similar to that of Ara-C. The maximum release rate of drugs from TSL was occurred at the near $T_c$ and observed at $39-41^\circ{C}$ for DPPC (Dipalmitoylphosphatidylcholine) only, $52-54^\circ{C}$ for DPPC and DSPC (1:1), respectively. Effect of human serum alburmin (HAA) on the release rate of ADM was investigated. HSA had no significant effect on the release of ADM below $T_c$. However, ADM release from TSL was increased at the near and above $T_c$. The HSA-induced leakage of drug may result from the interaction of liposomal constituents with HSA structure at the near TEX>$4^\circ{C}$. From the fact that the release profiles of ADM from freshly prepared TSL and stored TSL for 1 week at TEX>$4^\circ{C}$ was not changed, the TSL was considered to be stable for at least 1 week at TEX>$4^\circ{C}$. Based on these findings, TSL may be useful to deliver drugs to preheated target sites due to its thermal behaviors.

• Archives of Plastic Surgery
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• v.49 no.2
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• pp.166-173
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• 2022

The introduction of acellular dermal matrix (ADM) to breast reconstruction has allowed surgeons to reexplore the prepectoral implant placement technique in postmastectomy breast reconstruction. Our institution adopted a novel approach using meshed ADM to lessen the financial burden of increased ADM utilization with the prepectoral breast reconstruction. This is a retrospective, single-center review of two-stage prepectoral breast reconstruction using meshed human-derived ADM for anterior prosthesis coverage. Patient demographics, oncologic data, perioperative characteristics, and complications were examined and reported as means with standard deviations. Cost-saving with the meshed technique was evaluated. Forty-eight patients (72 breasts) with a mean age of 48.5 ± 15.0 years (range 26-70 years) were included in the study. The mean follow-up time was 13.2 ± 4.4 months (range 4.1-25.8 months). Nineteen breasts (24.6%) experienced complications, with seromas being the most common complication (12.5%, n = 9). Expander removal and reoperation occurred at a rate of 8.3 and 9.7%, respectively. The average time to drain removal was 18.8 ± 6.6 days (range 8-32 days). Meshed ADM provided an average cost savings of $6,601 for unilateral and $13,202 for bilateral reconstructions. Our study found that human-derived meshed ADM can be safely used in two-staged prepectoral tissue expander-based breast reconstruction and can result in significant cost savings.

• Archives of Plastic Surgery
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• v.42 no.3
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• pp.321-326
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• 2015

Background The acellular dermal matrix (ADM)-assisted breast reconstruction technique is widely known, but discouraging results due to early postoperative complications have been reported. As the literature identifies seroma as the most common issue after breast surgery without identifying its pathogenesis, we aimed to report the trend of postoperative daily serum collection after ADM-assisted breast reconstruction and compare it with data in the literature in order to discover more about this little-known topic. Methods A retrospective study on 28 consecutive patients who received ADM-assisted breast reconstruction between February 2013 and February 2014 was performed. In order to reduce the number of variables that could affect serum production, only one brand of ADM was used and all tissues were handled gently and precisely. The daily drainage volume was recorded per patient during the first four days of hospitalization. Likewise, postoperative complications were noted during routine follow-up. Results In total, five (17.9%) bilateral and 23 (82.1%) unilateral ADM-assisted breast reconstructions (33 implants) were performed. The mean age, body mass index, and length of hospital stay were 53.6 years, $21.3kg/m^2$, and 4.5 days, respectively. One major complication led to implant loss (3.0%), and nine minor complications were successfully treated with ambulatory surgery (27.3%). Serum collection linearly decreased after 24 hours postoperatively. Conclusions Daily drainage decreased following the theoretical decline of acute inflammation. In concordance with the literature, daily serum production may not be related to the use of ADM.

• Archives of Plastic Surgery
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• v.50 no.1
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• pp.3-9
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• 2023

Background In breast reconstruction, synthetic meshes are frequently used to replace acellular dermal matrix (ADM), since ADM is expensive and often leads to complications. However, there is limited evidence that compares the types of substitutes. This study aimed to compare complications between materials via a network meta-analysis. Methods We systematically reviewed studies reporting any type of complication from 2010 to 2021. The primary outcomes were the proportion of infection, seroma, major complications, or contracture. We classified the intervention into four categories: ADM, absorbable mesh, nonabsorbable mesh, and nothing used. We then performed a network meta-analysis between these categories and estimated the odds ratio with random-effect models. Results Of 603 searched studies through the PubMed, MEDLINE, and Embase databases, following their review by two independent reviewers, 61 studies were included for full-text reading, of which 17 studies were finally included. There was a low risk of bias in the included studies, but only an indirect comparison between absorbable and non-absorbable mesh was possible. Infection was more frequent in ADM but not in the two synthetic mesh groups, namely the absorbable or nonabsorbable types, compared with the nonmesh group. The proportion of seroma in the synthetic mesh group was lower (odds ratio was 0.2 for the absorbable and 0.1 for the nonabsorbable mesh group) than in the ADM group. Proportions of major complications and contractures did not significantly differ between groups. Conclusion Compared with ADM, synthetic meshes have low infection and seroma rates. However, more studies concerning aesthetic outcomes and direct comparisons are needed.