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The Effect of Platelets on Endothelin Production in Bovine Pulmonary Artery Endothelial Cells (혈소판이 소 폐동백 내피세포의 Endothelin 생산에 미치는 효과)

  • Lee, Sang-Do;Shim, Tae-Sun;Kwon, Seog-Woon;Ryu, Jin-Sook;Lee, Jae-Dam;Lim, Chae-Man;Koh, Youn-Suck;Kim, Woo-Sung;Kim, Dong-Soon;Kim, Won-Dong
    • Tuberculosis and Respiratory Diseases
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    • v.44 no.5
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    • pp.1114-1124
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    • 1997
  • Background : Endothelin(ET) is a very potent vasoconstrictive peptide produced by endothelial cells of pulmonary artery. The endothelin level was increased in plasma of primary pulmonary hypertension and acute pulmonary thromboembolism and it was suggested that the endothelin might do a critical role in the cardiopulmonary dysfunction in these two conditions. But the exact mechanism of increase of ET has not been known. In these two conditions, platelet activation and thrombosis are the main pathophysiologic findings. So there is a possibility that the platelet might stimulate endothelin secretion from endothelial cells. Therefore, we performed this study to evaluate the role of platelet and its mediators on endothelin production in bovine pulmonary artery endothelial(BPAE) cells. Method : Bovine pulmonary artery endothelial cells, ATCC certified cell line 209, were cultured and treated with human platelets($10^6{\sim}10^8/ml$), thrombin (0.1~10u/ml), TGF-${\beta}1$(1~100uM), serotonin(1~100uM), and endotoxin(1ug/ml) in a final volume of 500ul for 18 hours. Levels of ir(immunoreactive)-ET in each conditioned medium were measured by a radioimmunoassay specific for ET. Result : The increase of ir-ET levels was platelet number and time dependent over 18 hours. When washed human platelets were added($10^8/ml$), the ir-ET levels were significantly higher than that of control(p<0.05) at 8 and 18 hours after culture. Subthreshold concentration of platelets($10^7/ml$) coincubated with endotoxin(1ug/ml) or subthreshold dose of thrombin(0.1u/ml) stimulated ir-ET secretion from BPAE cells significantly(p<0.05) compared with control. Thrombin(1ug/ml, 10ug/ml) and TGF-${\beta}1$(100pM, 1000pM) significantly increased ir-ET secretion from BP AE cells(p<0.05) compared with control, but serotoin(1~100uM) and endotoxin(1ug/ml) did not stimulate the ir-ET secretion. Conclusions : Platelets stimulate endothelin secretion from bovine pulmonary artery endothelial cells. The mechanism of increase of endothelin secretion seems to be a stimulation by platelet itself or by mediators, such as TGF-${\beta}1$, secreted from activated platelets. And, in this study, the priming effect of platelets on endothelin secretion from BPAE cells could be another possibility.

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PS-341-Induced Apoptosis is Related to JNK-Dependent Caspase 3 Activation and It is Negatively Regulated by PI3K/Akt-Mediated Inactivation of Glycogen Synthase Kinase-$3{\beta}$ in Lung Cancer Cells (폐암세포주에서 PS-341에 의한 아포프토시스에서 JNK와 GSK-$3{\beta}$의 역할 및 상호관련성)

  • Lee, Kyoung-Hee;Lee, Choon-Taek;Kim, Young Whan;Han, Sung Koo;Shim, Young-Soo;Yoo, Chul-Gyu
    • Tuberculosis and Respiratory Diseases
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    • v.57 no.5
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    • pp.449-460
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    • 2004
  • Background : PS-341 is a novel, highly selective and potent proteasome inhibitor, which showed cytotoxicity against some tumor cells. Its anti-tumor activity has been suggested to be associated with modulation of the expression of apoptosis-associated proteins, such as p53, $p21^{WAF/CIP1}$, $p27^{KIP1}$, NF-${\kappa}B$, Bax and Bcl-2. c-Jun N-terminal kinase (JNK) and glycogen synthase kinase-$3{\beta}$ (GSK-$3{\beta}$) are important modulators of apoptosis. However, their role in PS-341-induced apoptosis is unclear. This study was undertaken to elucidate the role of JNK and GSK-$3{\beta}$ in the PS-341-induced apoptosis in lung cancer cells. Method : NCI-H157 and A549 cells were used in the experiments. The cell viability was assayed using the MTT assay and apoptosis was evaluated by proteolysis of PARP. The JNK activity was measured by an in vitro immuno complex kinase assay and by phosphorylation of endogenous c-Jun. The protein expression was evaluated by Western blot analysis. Dominant negative JNK1 (DN-JNK1) and GSK-$3{\beta}$ were overexpressed using plasmid and adenovirus vectors, respectively. Result : PS-341 reduced the cell viability via apoptosis, activated JNK and increased the c-Jun expression. Blocking of the JNK activation by overexpression of DN-JNK1, or pretreatment with SP600125, suppressed the apoptosis induced by PS-341. The activation of caspase 3 was mediated by JNK activation. Blocking of the caspase 3 activation suppressed PS-341-induced apoptosis. PS-341 activated the phosphatidylinositol 3-kinase (PI3K)/Akt pathway, but its blockade enhanced the PS-341-induced cell death via apoptosis. GSK-$3{\beta}$ was inactivated by PS-341 via the PI3K/Akt pathway. Overexpression of constitutively active GSK-$3{\beta}$ enhanced PS-341-induced apoptosis; in contrast, this was suppressed by dominant negative GSK-$3{\beta}$ (DN-GSK-$3{\beta}$). Inactivation of GSK-$3{\beta}$ by pretreatment with lithium chloride or the overexpression of DN-GSK-$3{\beta}$ suppressed both the JNK activation and c-Jun up-regulation induced by PS-341. Conclusion : The JNK/caspase pathway is involved in PS-341-induced apoptosis, which is negatively regulated by the PI3K/Akt-mediated inactivation of GSK-$3{\beta}$ in lung cancer cells.

Protective Effect of Plantago asiatica L. Leaf Ethanolic Extract Against Ferric Nitrilotriacetate-Induced Prostate Oxidative Damage in Rats (랫드에서의 Fe-NTA 유발 산화스트레스에 대한 차전초 에탄올 추출물의 전립선보호 효과)

  • Hong, Seung-Taek;Hong, Chung-Oui;Nam, Mi-Hyun;Ma, Yuan-Yuan;Hong, Yun-Jin;Son, Da-Hee;Chun, Su-Hyun;Lee, Kwang-Won
    • Journal of Food Hygiene and Safety
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    • v.26 no.3
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    • pp.260-265
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    • 2011
  • Plantago asiatica L. (P. asiatica) has been used as one of the popular folk medicines in Asia for human health care practices. Various activities of P. asiatica have been reported, such as anti-oxidant, anti-glycation, anti-inflammatory and hepatoprotective activity. Therefore, the potential of P. asiatica to reduce oxidative stress has been studied in several ways for over 20 years, especially at liver and kidney. However no investigation has been reported revealing its protective effect on prostate. Method: Treatment of P. asiatica leaf ethanolic extract (PLE) (1 g/kg body weight (b.w.), 2 g/kg b.w., or 4 g/kg b.w.) were given separately to animals for pretreatment once per day for 7 days, and on the seventh day ferric nitrilotriacetate (Fe-NTA; 0.24 mmol Fe/kg b.w.), which is known as an oxidative stress-inducer at prostate, was administrated by i.p to negative control group. At the end of the study period, dissection was carried out for detecting the prostate protective effect of PLE. Result: Fe-NTA-treated animals produced reactive oxygen species (ROS) resulting in depletion of antioxidant biomaker, such as glutathione (GSH), glutathione reductase (GR), and glutathione s-transferase (GST) and increase of lipid peroxidation in prostate. However, PLE pretreatment resulted in an increase in the GSH, GST and GR levels concentration dependent manner and in an significant decrease in the levels of lipid peroxidation. Conclusion: Our data suggest that PLE may be effective in protecting oxidative stress-induced damage of prostate, and PLE may be an chemopreventive agent against Fe-NTA-mediated prostate oxidative damage.

Preparation and Characterization of Physicochemical and Sensory Properties of Bread Enriched with Two Types of Wild Grape Extract (제조방법이 다른 두 종류의 머루즙 첨가가 빵의 이화학적 및 관능적 특성에 미치는 영향)

  • Lee, Byung-Yong;Lee, Malp-Eum;O, Jin-Hwan;Kim, Eun-Cho;Surh, Jeong-Hee
    • Korean journal of food and cookery science
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    • v.26 no.5
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    • pp.636-648
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    • 2010
  • Two types of wild grape extracts(WGE) prepared by different methods were added into butter-top bread at different concentrations(0, 5, 10, 15, 20% of water). Then, the resulting breads were analyzed for their physicochemical and sensory properties in order to identify whether or not the WGE-enriched breads were comparable to control bread in terms of qualities and preferences. Wild grape sugar mixture(WGS), which was prepared by osmotic dehydration of wild grape fruits with the same amounts of sugar, presented significantly lower moisture content and titratable acidity as well as higher pH and sugar content compared to wild grape juice(WGJ), which was produced by boiling the fruits in a vacuum jar and squeezing. The pH of the doughs and breads containing WGE tended to decrease with increasing amounts of WGE, and this phenomenon was more appreciable in those containing WGJ than WGS. This was presumably due to the higher contents of tartaric acid in WGJ. For both types of extracts, hardness, gumminess, and chewiness of the doughs decreased with the addition of WGE, nevertheless, which properties were not remained in the resulting breads. This could be partially attributed to the relatively high degree of baking loss and lower pH of the WGE-enriched breads than those of control bread. Contrary to the mechanical analyses, the sensory properties of the breads were dependent on the WGE type. That is, WGJ-enriched bread showed lower consistency and moistness than control bread, which consequently led to relatively lower overall acceptability. However, WGS addition did not adversely affect the sensory properties of the bread. In particular, addition of 5% WGS somewhat improved the physical and sensory qualities of the bread. Thus, WGE-enriched bread could be produced without loss of bread quality when prepared with 5% WGS.

Incidence of Chronic Pathologic Nephrotoxicity of Cyclosporine A in Pediatric Nephrotic Syndrome (소아 신증후군에서 Cyclosporine A에 의한 만성 조직학적 신독성의 발현빈도에 대한 연구)

  • Kim Ji-Hong;Jeong Hyun-Ju;Choi In-Jun;Kim Pyung-Kil
    • Childhood Kidney Diseases
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    • v.3 no.2
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    • pp.130-144
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    • 1999
  • Purpose : Long-term use of Cyclosporine(CsA) reduce renal blood flow by afferent arteriolar vasoconstriction and lead to chronic pathologic changes of CsA nephrotoxicity - 1) interstitial nephritis(IN); tubular atrophy (TA) and/or interstitial fibrosis(IF),2) arteriolopathy(AP). The Object of this study is to estimate the incidence of chronic pathologic CsA nephrotoxicity by duration of treatment and type of renal disease, relationship between histologic and clinical nephrotoxicity, and optimal duration of CsA therapy. Methods : 102 children with steroid resistant or dependent nephrotic syndrome confirmed by renal biopsy and treated with CsA from 1986 to 1997 were enrolled in this study(58 MCNS, 10 FSGS, 10 MGN, 15 $Henoch-Sch\"{o}nlein$ purpura nephritis with nephrotic syndrome (HSPN) and 9 IgA nephropathy with nephrotic syndrome(IgAN)). CsA was administered for 1yr, 1.5yr, 2yr in 24, 12, 22 MCNS patients and 2, 2, 6 FSGS patients respectively, 1yr, 2yr in MGN and 1yr in HSPN and IgAN. Sequential biopsies were done in all 102 patients after CsA treatment for evaluation of pathologic nephrotoxicity. Results : Complete remission rate was 92.2% (100% in MCNS and MGN, 80% in FSGS, 86.6% in HSPN and 55.5% in IgAN). Incidence of relapse during 6months after CsA treatment was significantly decreased compaed with relapsing spisodes during 6months before CsA treatment in MCNS(P<0.0001) and FSGS(P<0.0001). According to pathologic changes, 71 patients(69.6%) showed no pathological change, 24 patients(23.5%) showed IN and 7 patients(6.8%) showed AP. IN was 16.6%, 33.3%, 27.2% in 1, 1.5, 2 year of CsA treatment group in MCNS. AP was 0%, 16.6%, 9% in 1, 1.5, 2 year of CsA treatment group in MCNS. 14 out of 58 MCNS(24.1%) showed IN and 4 out of 58 MCNS(6.8%) showed AP. Incidence of pathologic change was significantly lower in CsA therapy of <1yr than >1yr(P=0.03). There were no significant difference of incidence of pathologic change in original renal disease, age and sex. Conclusion : Duration of CsA treatment was significant risk factor for nephrotoxicity and optimal duration seemed to be 1 year. Pathologic change due to nephrotoxicity did not correlate with deterioration of renal function and only detectable by renal biopsy.

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Tetralogy of Fallot Associated with Pulmonary Atresia and Major Aortopulmonary Collateral Arteries -Comparison between the different surgical approaches- (폐동맥폐쇄와 주대동맥폐동맥혈관부행지를 동반한 활로씨사징증 -다양한 외과적 치료접근의 비교-)

  • 이정렬;양지혁;김용진;노준량
    • Journal of Chest Surgery
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    • v.32 no.5
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    • pp.471-479
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    • 1999
  • Background: Patients with tetralogy of Fallot(TOF), pulmonary atresia(PA) and major aortopulmonary collateral arteries(MAPCAs) have been managed by heterogenous surgical strategies. We have taken 5 different surgical approaches to this lesion. In this study, relative advantages and disadvantages of each strategy were discussed by analyzing our surgical results. Material and Method: Between January 1986 and June 1998, 50 patients aged 1 to 177(39${\pm}$31) months at a various morphologic spectrum of this lesion were treated at our institution. The groups, which were classified according to the initial approaches, consisted of one-stage unifocalization(A-1, n=9), staged unifocalization(A-2, n=11), right ventricle to pulmonary artery connection(RV-PA)(B-1, n=11), one-stage RV-PA plus unifocalization (B-2, n=11), and one-stage definitive repair(C, n=8). Morphologic charateristics, operative mortalities, and probabilities of definitive repair were compared between the groups and the causes of death, complications and the follow-up results were described. Result: Mean ages at the first operation were 57${\pm}$18(A-1), 42${\pm}$48(A-2), 18${\pm}$14(B-1), 52${\pm}$55(B-2), and 32${\pm}$34(C) months (p<0.05). Mean numbers of MAPCAs were least in group C (A-1=4.3${\pm}$1.0, A-2=4.5${\pm}$1.3, B-1=4.1${\pm}$1.9, B-2=4.1${\pm}$1.6, C=3.4${\pm}$1.8 : p<0.05). The ratios of the direct and the indirect MAPCAs in each group were not different between the grousps (A-1=91%/9%, A-2=78%/22%, B-1=80%/20%, B-2=80%/20%, C=81%/19% : p>0.05). Nineteen patients had more than 1 dependent MAPCAs. True pulmonary arteries were not present 13 patients and they were confluent in 29. A total of 101 operations were performed. Operative mortalities of initial procedures were 33%(3/9, A-1), 18%(2/11, A-2), 0%(0/11, B-1), 36%(5/11, B-2) and 13%(1/8, C) (p<0.05). Percentages of the definitive repair among the patients of each group were 22%(2/9, A-1), 18%(2/11, A-2). 45%(5/11, B-1), 27%(4/11, B-2), and 100%(8/8, C)(p<0.05). Hypoxic respiratory and cardiac failure(6), hypoxic encephalopathy(2) and sepsis(4) were the major causes of death. Phrenic nerve palsy occured in 5 patients. Thirty-one patients among the survivals have been followed up for a mean duration of 74${\pm}$42(3-145) months. One and five year actuarial survival rates were 73% and 73 %. Conclusion: In conclusion, Right ventricle to pulmonary artery connection used in patients with TOF/PA/MAPCA as an inital procedure appeared to be highly successful in enhancing the chance of satisfactory definitive repair without the significant surgical risks. One-stage total repair at an ealier age group could be performed safely with the resonable outcomes. Unifocalization approach, whether it was performed in a single stage or in the multiple stages, resulted in the high operative mortality and the lowest chance of definitive repair, however more tailored selection of the patients and the long follow-up is mandatory to prove the usefulness of this approach.

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Perceptions of Married Women on Childbirth and Sex Preference and Related Factors in Gyeongju, Korea (도농복합지역 기혼여성들의 출산과 성 선호에 대한 인식 및 관련요인)

  • Youm, Seog-Heon;Kang, Pock-Soo;Kim, Chang-Yoon;Lee, Kyeong-Soo;Hwang, Tae-Yoon;Hwang, In-Sob
    • Journal of agricultural medicine and community health
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    • v.35 no.3
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    • pp.260-273
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    • 2010
  • Objectives: The purpose of this study was to investigate the perceptions of married Korean women regarding marriage and childbirth, and their awareness of childbirth-related issues such as low birth rates, sex preferences and sex imbalances in Korea. Methods: A total of 453 married women aged 20 or older were randomly selected from four urban districts and five rural districts out of 25 districts in Gyeongju, a consolidated city located in Gyeongsangbuk-do Province, South Korea. The survey was conducted from December 2005 to February 2006. A total of 392 out of 453 questionnaires(86.5% response rate) were collected, and 44 incomplete questionnaires were excluded, leaving 348 completed questionnaires to be used for data analysis. Age was divided into three groups as below 49, 50-69, 70 or older. Results: Women's perceptions of marriage were associated with age(p<0.01). Perceptions about childbirth were also significantly related to age(p<0.01), type of residential area (p<0.01) and education level(p<0.05). Sex preferences were significantly related to age(p<0.05) and occupation(p<0.01). Of the respondents aged 49 or younger, 34.8% indicated that the ideal number of children is two, while 25.5% of respondents aged 50 to 69 and 15.3% of respondents aged 70 and 33.7% of respondents aged 70 or older considered four children to be the ideal number. Perceptions of sex imbalance were significantly related to socioeconomic status(p<0.01) and occupation(p<0.01). The largest number of respondents cited "economic burden" as the main reason for low birth rates. Multiple logistic regressions were performed for all three age groups using male sex preference as the dependent variable under the assumption that respondents can have only a single child. Socioeconomic status (p<0.01) and residential area (p<0.05) were significant variables for those aged 49 or below. Education level(p<0.05) and residential area (p<0.01) were statistically significant variables on preferring son in case of having only one child for respondents aged 50 to 69. We did not detect any significant independent variables in respondents who were 70 or older. Conclusions: Our results highlight the necessity of developing policies and public education programs to explain the consequences of low birth rates and sex imbalances in Korea. As increasing numbers of women work outside the home, it is important for the government and employers to provide social and working environments where women do not consider marriage and childbirth to be obstacles to social and business activities.

FAMILY DYNAMICS OF INCEST PERCEIVED BY ADOLESECENTS (청소년이 지각한 근친상간의 가족역동)

  • Kim, Hun-Soo;Shin, Hwa-Sik
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • v.6 no.1
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    • pp.56-64
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    • 1995
  • Family is a primary unit of the major socialization processing for children. Parents among the family members are one of the most important figures from whom the child and adolescent acquire a wide variety of behavior patterns, attitudes, values and norms. An organization of family members product family structural functioning. Abnormal family structure is one of the most important reference models in the learning of antisocial patterns of behavior. Therefore incest and child sexual abuse including spouse abuse, elderly abuse, and neglect occurs in the abnormal family structural setting. In particular, incest, a specific form of sexual abuse, was once thought to be a phenomenon of great rarity, but our clinical experiences, especially over the past decade, have made us aware that incest and child sexual abuse is not rare case and on the increasing trend. Therefore, the aim of this study was to determine the family problem and dynamics of incest family, and character pattern of post-incest adolescent victim in Korea. A total of 1,838 adolescents from middle and high school(1,237) and juvenile correctional institute(601) were studied, sampled from Korean student population and adolescent delinquent population confined in juvenile correctional institutes, using proportional stratified random sampling method. The subjects' ages ranged from 12 to 21 years. Data were collected through questionnaire survey. Data analysis was done by IBM PC of Behavior Science Center at the Korea university, using SAS program. Statistical methods employed were Chi-square, principal component analysis and t-test etc. The results of this study were as follows ; 1) Of 1,071 subjects, 40(3.7%) reported incest experiences(sibling incest : 1.6% ; another type of incest : 2.1%) in their family setting. 2) The character pattern of post-incest adolescent victim was more socially maladjusted, immature, impulsive, rigid, anxious and dependent than non-incest adolescent. Also they showed some problem in academic performance and their assertiveness. 3) The other family members of incest family revealed more psychological and behavioral problem such as depression, alcoholism, psychotic disorder and criminal act than the non-incest family, even though there is no evidence of the context between them. 4) The family dynamics of incest family tended to be dysfunctional trend, as compared with non-incest family. It showed that the psychological instability of family member, parental rejection toward their children, coldness and indifference among family member and marital discordance between the parents had significant correlation with incest.

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An Iterative, Interactive and Unified Seismic Velocity Analysis (반복적 대화식 통합 탄성파 속도분석)

  • Suh Sayng-Yong;Chung Bu-Heung;Jang Seong-Hyung
    • Geophysics and Geophysical Exploration
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    • v.2 no.1
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    • pp.26-32
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    • 1999
  • Among the various seismic data processing sequences, the velocity analysis is the most time consuming and man-hour intensive processing steps. For the production seismic data processing, a good velocity analysis tool as well as the high performance computer is required. The tool must give fast and accurate velocity analysis. There are two different approches in the velocity analysis, batch and interactive. In the batch processing, a velocity plot is made at every analysis point. Generally, the plot consisted of a semblance contour, super gather, and a stack pannel. The interpreter chooses the velocity function by analyzing the velocity plot. The technique is highly dependent on the interpreters skill and requires human efforts. As the high speed graphic workstations are becoming more popular, various interactive velocity analysis programs are developed. Although, the programs enabled faster picking of the velocity nodes using mouse, the main improvement of these programs is simply the replacement of the paper plot by the graphic screen. The velocity spectrum is highly sensitive to the presence of the noise, especially the coherent noise often found in the shallow region of the marine seismic data. For the accurate velocity analysis, these noise must be removed before the spectrum is computed. Also, the velocity analysis must be carried out by carefully choosing the location of the analysis point and accuarate computation of the spectrum. The analyzed velocity function must be verified by the mute and stack, and the sequence must be repeated most time. Therefore an iterative, interactive, and unified velocity analysis tool is highly required. An interactive velocity analysis program, xva(X-Window based Velocity Analysis) was invented. The program handles all processes required in the velocity analysis such as composing the super gather, computing the velocity spectrum, NMO correction, mute, and stack. Most of the parameter changes give the final stack via a few mouse clicks thereby enabling the iterative and interactive processing. A simple trace indexing scheme is introduced and a program to nike the index of the Geobit seismic disk file was invented. The index is used to reference the original input, i.e., CDP sort, directly A transformation techinique of the mute function between the T-X domain and NMOC domain is introduced and adopted to the program. The result of the transform is simliar to the remove-NMO technique in suppressing the shallow noise such as direct wave and refracted wave. However, it has two improvements, i.e., no interpolation error and very high speed computing time. By the introduction of the technique, the mute times can be easily designed from the NMOC domain and applied to the super gather in the T-X domain, thereby producing more accurate velocity spectrum interactively. The xva program consists of 28 files, 12,029 lines, 34,990 words and 304,073 characters. The program references Geobit utility libraries and can be installed under Geobit preinstalled environment. The program runs on X-Window/Motif environment. The program menu is designed according to the Motif style guide. A brief usage of the program has been discussed. The program allows fast and accurate seismic velocity analysis, which is necessary computing the AVO (Amplitude Versus Offset) based DHI (Direct Hydrocarn Indicator), and making the high quality seismic sections.

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APPROXIMATE ESTIMATION OF RECRUITMENT IN FISH POPULATION UTILIZING STOCK DENSITY AND CATCH (밀도지수와 어획량으로서 수산자원의 가입량을 근사적으로 추정하는 방법)

  • KIM Kee Ju
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.8 no.2
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    • pp.47-60
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    • 1975
  • For the calculation of population parameter and estimation of recruitment of a fish population, an application of multiple regression method was used with some statistical inferences. Then, the differences between the calculated values and the true parameters were discussed. In addition, this method criticized by applying it to the statistical data of a population of bigeye tuna, Thunnus obesus of the Indian Ocean. The method was also applied to the available data of a population of Pacific saury, Cololabis saira, to estimate its recuitments. A stock at t year and t+1 year is, $N_{0,\;t+1}=N_{0,\;t}(1-m_t)-C_t+R_{t+1}$ where $N_0$ is the initial number of fish in a given year; C, number o: fish caught; R, number of recruitment; and M, rate of natural mortality. The foregoing equation is $$\phi_{t+1}=\frac{(1-\varrho^{-z}{t+1})Z_t}{(1-\varrho^{-z}t)Z_{t+1}}-\frac{1-\varrho^{-z}t+1}{Z_{t+1}}\phi_t-a'\frac{1-\varrho^{-z}t+1}{Z_{t+1}}C_t+a'\frac{1-\varrho^{-z}t+1}{Z_{t+1}}R_{t+1}......(1)$$ where $\phi$ is CPUE; a', CPUE $(\phi)$ to average stock $(\bar{N})$ in number; Z, total mortality coefficient; and M, natural mortality coefficient. In the equation (1) , the term $(1-\varrho^{-z}t+1)/Z_{t+1}$s almost constant to the variation of effort (X) there fore coefficients $\phi$ and $C_t$, can be calculated, when R is a constant, by applying the method of multiple regression, where $\phi_{t+1}$ is a dependent variable; $\phi_t$ and $C_t$ are independent variables. The values of Mand a' are calculated from the coefficients of $\phi_t$ and $C_t$; and total mortality coefficient (Z), where Z is a'X+M. By substituting M, a', $Z_t$, and $Z_{t+1}$ to the equation (1) recruitment $(R_{t+1})$ can be calculated. In this precess $\phi$ can be substituted by index of stock in number (N'). This operational procedures of the method of multiple regression can be applicable to the data which satisfy the above assumptions, even though the data were collected from any chosen year with similar recruitments, though it were not collected from the consecutive years. Under the condition of varying effort the data with such variation can be treated effectively by this method. The calculated values of M and a' include some deviation from the population parameters. Therefore, the estimated recruitment (R) is a relative value instead of all absolute one. This method of multiple regression is also applicable to the stock density and yield in weight instead of in number. For the data of the bigeye tuna of the Indian Ocean, the values of estimated recruitment (R) calculated from the parameter which is obtained by the present multiple regression method is proportional with an identical fluctuation pattern to the values of those derived from the parameters M and a', which were calculated by Suda (1970) for the same data. Estimated recruitments of Pacific saury of the eastern coast of Korea were calculated by the present multiple regression method. Not only spring recruitment $(1965\~1974)$ but also fall recruitment $(1964\~1973)$ was found to fluctuate in accordance with the fluctuations of stock densities (CPUE) of the same spring and fall, respectively.

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