스파이크 검출 기반의 적응적 지터 추정

최홍재(Hong Jae Choi),김형국(Hyoung Gook Kim) 한국통신학회 2012 한국통신학회 학술대회논문집 Vol.2012 No.6

EM(Effective Microorganism)을 이용한 음식물쓰레기의 악취 절감 효과

최홍재 ( Hong Jae Choi ),이영옥 ( Young Ok Lee ) 한국물환경학회 ( 구 한국수질보전학회 ) 2012 한국물환경학회·대한상하수도학회 공동 춘계학술발표회 Vol.2012 No.-

스마트TV향 VoIP 컨퍼런스 기능을 위한 잡음제거 알고리즘의 성능비교

서광덕(Seo, Kwang-duk),최홍재(Choi, Hong-Jae),김형국(Kim, Hyoung-Gook) 한국방송·미디어공학회 2011 한국방송공학회 학술발표대회 논문집 Vol.2011 No.7

본 논문에서는 스마트TV향 VoIP(Voice over Internet Protocol) 컨퍼런스 기능을 위한 잡음제거 알고리즘의 성능비교 하였다. 기존에 연구 되어져 있는 Improved Minima Controlled Recursive Averaging(IMCRA)방식과 Gaussian분포 기반의 잡음제거 알고리즘, IMCRA방식과 Gamma분포 기반의 잡음제거 알고리즘, IMCRA방식과 Mel-filter를 적용한 잡음제거 알고리즘, R&L 알고리즘들의 방식을 비교하였으며, 성능 비교를 위해 각 알고리즘을 통해 나온 다양한 잡음 환경에서의 잡음이 제거된 신호의 PESQ와 연산속도를 비교한다.

위암환자의 위배출시간에 관한 연구

황성오(Sung Oh Hwang),이상주(Sang Joo Lee),이상인(Sang In Lee),박인서(In Suh Park),최홍재(Heung Jai Choi),박창윤(Chang Yun Park) 대한내과학회 1990 대한내과학회지 Vol.39 No.2

N/A Gastric emptying in patients with stomach cancer can be influenced by several factors, such as location, size, depth of invasion, and gross morphology. In order to identify the change of gastric emptying in patients with stomach cancer, a gastric emptying scan using solid test meal (99mTc-DTPA labeled scrambled egg: was performed on 12 healthy subjcts and 44 patients with stomach cancer. The results were as follows: 1) The mean of gastric emptying times (GET, T1/2) in the control group was 35.8±12.1 (Mean±S.D) minutes, and the gastric emptying rate (GER) at 60 minutes after ingestion of test meal was 75.1%. 2) In the stomach cancer group, the mean of GET was delayed (56.7±37.4 minutes) compared with that of the control group, although insignificant statistically, and the GER at 60 minutes was reduced (57.8%) more than in the control group. 3) In patients with a tumor located distally, invaded beyond the muscle layer (T2-T4 group) or larger than 5 cm in diameter, the mean of GET was delayed, and the GER at 60 minutes was reduced more than in the control group(p<0.05). 4) In patients with tumor of Borrmann's type II, type III, and type IV, the mean of GET was delayed, and the GER at 60 minutes was reduced more than in the contro1 group (p<0.05). In conclusion, gastric emptying of solid meal in patients with stomach cancer was delayed in cases with a tumor located distally. invaded beyond the muscle layer, or involved extensively.

경피 내시경하 위루술을 이용한 위감압 치험

박인서(In Suh Park),이상인(Sang In Lee),이관식(Kwan Sik Lee),박효진(Hyo Jin Park),신준한(Joon Han Shin),최홍재(Heung Jai Choi),권선옥(Seon Og Kweon),정준표(Jun Pyo jeong) 대한소화기학회 1993 대한소화기학회지 Vol.25 No.2

Percutaneous endoscopic gastromy (PEG) and percutaneous endoscopic jejunostomy (PEJ) are used commonly for enteral feeding. Rut there were some reports of using PEG as an alternative to naso-gastrointestinal tube for decompression in parients with mechanical obstruction, particularly obstraction with malignancies involving the upper gastrointesrinal tract. Palliation is usually achieved by the placement of a nasogastric or nasointestinal tube. Hower these tubes tend to have some disadvantages which can be overcome with drainage PEG. In our experience, a 65 years old male patiert with pyloric obstruction due to advanced gastric cancer was successfly decompressed by drainage PEG. Thus, we present this case with supporting literatures.

만성 B 형 활동성 간염 환자에서 Prednisolone 이탈요법후의 알파인터페론 병용투여의 치료 효과

한광협(Kwang Hyup Han),김경희(Kyung Hee Kim),홍성표(Sung Pyo Hong),김원호(Won Ho Kim),전재윤(Chae Yoon Chon),이상인(Sang In Lee),문영명(Young Myoung Moon),강진경(Jin Kyung Kang),박인서(In Suh Park),최홍재(Heung Jai Choi),박찬일(Chan 대한내과학회 1990 대한내과학회지 Vol.39 No.3

N/A To evaluate the efficacy of a short course of prednisolone withdrawal followed by recombinant alpha interferon (rIFNa 2-a) treatment with chronic active hepatitis B (CAHB), forty patients with peritoneoscopic, liver biopsy-proven CAHB were randomized to receive either a 3 week tapered course of prednisolone followed by rIFNa 2-a (Alpha-Feron) or no treatment. All patients were HBeAg positive and two groups were comparable with respect to age, sex and biochemical and histologic data. Interferon was administered at a dose of 6 million units (mu) given I.M. qd for 1 week and at the same dose thvee times a week for 15 weeks after prednisolone withdrawal. Transient side effects occurred in all treated patients, but the treated patients all tolerated and concluded treatment without side effects serious enough to give up the trials. Twelve of 20 treated patients (60%) cleared HBeAg and eleven patients (55%) seroconverted from HBeAg to antiHBe, whereas five of 20 control patients (25%) cleared HReAg and only two control patients (10%) seroconverted during a mean follow-up interval of 12 months. The seroconversion rate of HBeAg was significantly higher in treated groups than control (p<0.05). None of the treated or control patients became negative for HBsAg. The ALT normalization rate at last followup was higher in treated groups (60%) than control groups (35%) but there was no significant difference. Comparison of responders (n=10) to non-responders (n=10) indicated that there was no significant difference in age, sex and pretreatment ALT levels and HBV-DNA values. The responsers who had follow-up liver biopsy had improvement in liver histology. In conclusion, these results suggest that a short course of prednisolone withdrawal followed by rIFNa 2-a can be effective for selected patitns with HBeAg-positive CAHB.

위암환자에서 수술전 Polyadenylic-Polyuridylic Acid 투여가 말초혈액과 영역림프절 단핵구의 NK 및 LAK 활성도에 미치는 영향

김원호,강진경,박인서,함기백,윤정구,민진식,노성훈,최홍재,전미연 대한소화기학회 1992 대한소화기학회지 Vol.24 No.2

Although the biological significance of the regional lymphnode as a barrier to tumor remains unclear, the clinical prognostic relevance of the neoplastic infiltration of these nodes is accepted. The most potent antitumor effector cells may be expected to be present within or around the site of tumor growth. However, lymphocytes isolated from solid tumor, cancer ascites fluid, and carcinomatous pleural effusion have been shown to expresse low natural killer (NK) activity or none at all. Similarly, it has been reported that lymphnode can be regarded as an NK-deficient tissue, since more limited cytotoxic activity is recorded in the lymphnode cells. Although there is general agreement that the NK and lymphokine-activated killer (LAK) activities of peripheral blood mononuclear cells (PBMC) decrease in patients with various tumors, this decrease remains unclear with regard to the cytotoxic activities of their regional lymphnode mononuclear cells (LNMC), especially after in vitro stimulation by lymphakines or after in vivo administration of biological response modifier (BRM). Polyadenylic-polyuridylic acid [poly (A)·poly (U)], a nontoxic double-stranded complex of synthetic polyribonucleotides has been successfully used as an adjunt to surgery in animal tumors as well as resectable human breast and gastric cancers. The mechanisms governing the antitumor action of poly (A)·poly (U) has been discussed with respect to various biological effects such as immunomodulation for both humoral and cell-mediated immune responses, induction of interferon, and enhancement of NK cell activity. However, detection of serum interferoin induced be poly (A)·poly (U) is very difficult, because low dose of poly (A)·poly (U) lead to not sufficient production of detectable levels of interferon and half-life of circulating interferon is very short. Under these conditions, the interferon-mediated enzymes [2´, 5´-oligoadenylate synthetase (2´, 5´-AS) and p67K kinase] are enhanced, and the degree of enhancement is correlated with the dose of poly (A)·poly (U). Therefore, these enzymes may be used as convenient remarkers to monitor the interferon-inducing effect of poly (A)·poly (U). It is of interest to assess whether the in vivo administration of poly (A)·poly (U) auguments the NK and LAK activities and 2´, 5´-AS activity of PBMC and LNMC. So, the present study was designed to investigate the effects of the in vivo administration of poly (A)·poly (U) on the NK and LAK activities arid 2´, 5´-AS activities of PBMC and LNMC from patients with gastric icarcinoma. Fourtyseven patients with refectable gaatsic carcinanta were divided into poly (A)· poly (U)-non-treated group (26 patients) and poly (A) poly (U)-treated group (21 patients) to whom 100 mg of poly (A)·poly (U) was intravenously adkninisterded 3 times preoperatively. NK and LAK activities of PBMC and LNMC were measured by 4 hour ^(51)Cr-release assay using K562 and Raji cells as targets and 2´, 5´-AS actavitiea were measufed by measuring 2´, 5´-A produced by 2´, 5´-AS attached to polyinosinie-polyeytidilc acid agaroge bead. The results obtained are as follows: 1) NK and LAK activities of LNMC were significantly lower than those of PBMC from patients with gastric carcinoma. 2) AS the stage of gaatrtc carcinoma progressed, NK and LAK activities of PBMG decreased but those of LNMC did not. No differences were found in NK and LAK activities of LNMC, whether regional lymplnodes were infiltrated or not by the carcinoma. 3) 2´, 5´-AS activities of LNMC were sightly higher than those of PBMC. 4) 2´, 5´-AS activities of PBMC showed decreasing tendency and those of LNMC showed increasing tendency according to the stage of gastric carcinoma. 5) After administration of poly (A)·poly (U), NK and LAK activities of PBMC increased but those of LNMC did riot. 6) After administration of poly (A)·poly (U), 2´, 5´-AS activities of PBMC and LNMC showed increasing tendency. These results suggest that even though NK and LAK activtiea of LNMC were significantly lower than those of PBMC, 2´, 5´-AS activitiy of LNMC were maintained in high level even in patients with gastric carcinoma. And anti-cancer effect of poly (A)·poly (U) in patients with gastric carcinoma may be related with augumented 2´, 5´-AS activities of PBMC and LNMC as well as enhanced NK and LAK activities of PBMC after administration of poly (A)·poly (U).

각종 간질환에 있어서 이상 Prothrombin (des-γ-Carboxyprothrombin)에 관한 연구

이혁우,정경섭,김원호,한광협,정재복,이상인,박인서,최홍재,도윤정,윤홍섭 대한내과학회 1990 대한내과학회지 Vol.38 No.4

The absence of vitamin K or the ingestion of vitamin K antagonists inhibits vitamin K-dependent carboxylase activity in the liver, and an abnormal prothrombin, known as des-y-carboxyprothrombin(DCP) or PIVKA -Ⅱ(a protein induced by vitamin K absence or antagonists-Ⅱ), is released into the blood. In order to evaluate whether abnormal prothrombin levels can be clinically used as an index of hepatocellular dysfunction or as a tumor marker of hepatocellular carcinoma(HHC), DCP levels were determined by a latex agglutination test in 20 normal subjects and in patients with various liver diseases, including 70 hepatocellular carcinoma, sever metastatic liver disease, 45 liver cirrhosis, 13 acute viral hepatitisB, six chronic active hepatitis B, three fatty liver and one liver abscess. The usefulness of the combination assay of DCP and alpha-fetoprotein(AFP) levels to improve the diagnostic value and the effects of vitamin K administration on DCP levels were assessed in the present study. The results obtained were as follows: 1) DCP was detected in 42 out of 70 patients with HCC(60.0%), in three seven patients with metastatic liver disease(42.9%), in 23 out of 45 patients with liver cirrhosis(51.1%), and in one out of six patients with chronic active hepatitisb(16.7%), but there was no detectable DCP among the 20 healthy control subjects or in the 13 acute viral hepatitis B, three fatty liver and one liver abscess cases. 2) The detection rates of DCP according to the size of the HCC were 66.7% in the larger-than 5㎝ size and 44.4% in the 3~5㎝ size, but there was no detection in four patients with smaller-than 3㎝ size. The detection rates of DCP according to Child’s classification of liver cirrhosis were 60% in class C and 25% in class B, but there was no detection in two patients in class A. 3) There was no significant correlation between DCP and AFP levels. However, DCP was also detected 62.5% in less than 400ng/㎖ of AFP, and the positive rates were 91.0% in higher than 400ng/㎖ of AFP or higher than 1:10(+) of DCP in patients with HCC. 4) The detection rate of DCP was 56.8% in liver cirrhosis patients with prolonged prothrombin time(PT). However, 61.4% was detected in HCC patients with normal levels of prothrombin time(PT). 5) On observation of the effectiveness of vitamin K administration on DCP level, are was no effectiveness of vitamin K administration in all patients with 13 HCC, but the DCP level decreased or was not detected in seven out of nine patients with liver cirrhosis after vitamin K administration (p<0.05). Based on these results, DCP determined by a latex agglutination test may be useful as an index of hepatocellular dysfunction. However, due to the lower sensitivity and specificity of the latex agglutination test, it is doubtful whether DCP is a definite tumor marker of HCC. But the combination assay of AFP and DCP is helpful for obtaining an increased diagnostic rate of HCC. We recommended comparison of the effectiveness of vitamin K administration on DCP concentrations during the follow-up observation of chronic liver disease, such as liver cirrhosis, for increasing the diagnostic rate of HCC. Further study utilizing methods such as RIA or ELISA might be needed to evaluate the usefulness of DCP as a tumor marker for HCC.

각종 간질환 환자에서 혈중 lipoprotein(a)농도의 변화

김원호,강진경,박인서,전재윤,한광협,함기백,최홍재,김치정,김한수,백승운,김은주 대한소화기학회 1992 대한소화기학회지 Vol.24 No.2

Lipoprotein (a) [Lp (a)] is a LDL-like lipoprotein whose concentrations in plasma are significantly are correlated with atherosclerosis. The characteristic protein compoment of Lp (a) is apoliporotein (a) which is linked to apolipoprotein B-100 by disulfide bonds. Although Lp (a) might play an important role in the development of premature atherosclerotic vascular lesions, only scarse information about the metabolism of this lipoprotein is available. The major site of synthesis of Lp (a) appers to be the liver because it was found that a complete conversion of the Lp (a) phenotype of thc receipient to that of the donor occurs after liver transplantation and presence of apo (a) mRNA in human liver and hepatoma cell line. Until the present time, little information is available about determining the influence of liver disease on Lp (a) concentration. This study was designed to find out the changes of Lp (a) concentrations in 88 patients with various liver diseases, diagnosed histologically through the peritoneoscopic liver biopsy. The Lp (a) concentrations were checked by the method of radioimmunoassay. The mean Lp (a) concentrations of CAH with LC (6.1±4.8 ㎎/㎖) and LC group (4.1±2.2 ㎎/㎖) were significantly lower than those of normal control (24.4±19.1 ㎎/㎖), CPH (25.4±18.5㎎/㎖), and CAH group (16.6±13.7 ㎎/㎖). The Lp (a) concentrations were significantly correlated with serum albumin concentrations (r=0.54 p$lt;0.05) and prothrombin time (r=0.62, p$lt;0.01). There was a significant difference in mean Lp (a) coincentration between the cases with serum albumin above and below 3.0 g/ml in patients with liver cirrhosis. These data suggest that lipoprotein (a) may be secreted frorn the liver in accordance with the capability of liver to synthesize the protein and we find out that as the liver diseases progressed and deteriorated, the levels of Lp (a) concentrations were significantly decreased.

췌장종양에서의 Ras 암유전자

김원호,강진경,박인서,박영년,정재복,송시영,최홍재,전미연 대한소화기학회 1992 대한소화기학회지 Vol.24 No.4

Point mutations leading to the activation of ras genes represent one of the best-studied mechanisms that convert proto-anocogenes into transforming sequences. The human ras gene family comprises 3 active members, H-ras, K-ras and N-ras and a growing list of distantly related genes. The 21-kDa ras proteins are located at the inner surface of the plasma membrane, bind guanine nucleotides and possess intrinsic GTPase activity. Although precise physiological function of ras-encoded proteins remains to be elucidated, it appears that they are involved in transduction of receptor-mediated external sigruals across the cell membrane. The incidence of ras gene mutations varies among different kinds of tumors. The highest incidence of ras gene nlutatians was reported in pancreatic adenocarcinomas, where about 90% of the tumors showed a mutant K-ras gene. In addition, despite seven possible sites of mutation in the ras genes, the mutations found to date have been restricted in colon 12 of the K-ras gene in pancreatic adenocarcinoma. However there have been no report on ras gene mutation of the pancreatic tumor in Korea, To evaluate the frequency of K-ras gene mutations, we analyzed the paraffin-embedded sections obtained from 6 cases of pancreatic adenocarcinama, 3 cases of mutinous cystadenoma (including mucin-secreting ductectatfc type of rnucinous cystadenma) and 1 case of mutinous cystadenocarcinoma by in vitro amplification of target sequences via polymerase chain reaction and selective oligonucleotide hybridization. Specific point mutation ask K-ras talon 12 was found in 1 of 6 cases of pancreatic cancer. The point mutation was a G-to-A transition at the second base (aspartic acid substitution). No mutations were found in all cases with mutinous cystadenoma, mutinous cystadenocarcinoma and adjacent normal pancreatic tissues. We might Conclude that K-rays activation at colon 12 might be related to the pancreas cancer but a more extencive analysis ineluding direct sequencing at colon 12, 13 and 61 will be required to determine whether there are carrelhtions of pancreatic cancer with point mutations or not.