사람과 흰쥐의 고환에서 Aquaporin 유전자의 발현

박남철,박영수,오금수,정진섭,Park, Nam-Cheol,Park, Young-Soo,Oh, Gom-Su,Jung, Jin-Sup 대한생식의학회 2000 Clinical and Experimental Reproductive Medicine Vol.27 No.2

Objective: Several water channels (aquaporins; AQP) that belong to the MIP (major intrinsic protein) family have identified. In the selected tissues including red blood cells or renal tubules, water movements are abundant and/or physiologically important. Unexpectedly, a high water permeability of human and ram sperm has been reported. Recent studies showed that AQP7 and AQP8 are present in testes, so that the high water permeability of human sperm suggested to be mediated by AQPs. Method: To identify the identity of aquaporins expressed in testes, RT-PCR was performed using degenerative primers, which were designed to correspond to highly conserved sequences surrounding the Asn-Pro-Ala (NPA) motifs in the aquaporins. New expressed AQP series were reconfirmed by immunohistochemical study using rabbit polyclonal antibodies. Results: DNA sequencing of PCR products revealed that AQP2 and AQP3 mRNA as well as AQP7 and AQP8 are expressed in human and rat testes. In human and rat testes, AQP2 are expressed in spermatozoa, interstitial cells and myofibroblasts and AQP3 are expressed in myofibroblasts of semineferous tubules on immunocytochemical stain. Conclusion: These results indicate that multiple aquaporins are expressed in testes, and that they may have important roles in the spermatogenesis and the germ cell function of testis.

기상산업의 변화와 전망

박남철,Park, Nam-Cheol 환경보전협회 2009 환경정보 Vol.31 No.381

정장액내의 금속성분이 정액지표 및 가임능에 미치는 영향

박남철,김민수,윤종병,Park, Nam-Cheol,Kim, Min-Soo,Yoon, Jong-Byung 대한생식의학회 1997 Clinical and Experimental Reproductive Medicine Vol.24 No.1

To determine the concentration and the physiologic role of metal components in blood plasma and seminal plasma in relation to male infertility, the concentrations of twelve metal components in blood plasma and seminal plasma including Na, Mg, K, Ca, Cr, Mn, Fe, Cu, Zn, Se, Cd and Pb were measured by atomic absorbance spectrophotometery or ion selective electrode analysis. Semen and blood samples were obtained from a total of 110 men including 70 male infertility patients, 20 vasectomized persons and 20 fertility proven volunteers visited to the Male Infertility Clinic of Pusan National University Hospital. The concentrations of Ca, Zn, Mg, Cr and Cd in control group were higher in seminal plasma than in blood plasma, and additionally Pb were higher in infertility group. The concentrations of all metal components revealed no significant difference according to patients' age, resident, occupation, sperm density, motility and hormone level in blood plasma, but some metal components including Ca, Mg, Cu, Mn, Cd and Pb revealed a significant difference according to each these parameters except patient's age in seminal plasma. The concentrations of Mn, Cd and Pb in the vasectomy persons were higher than in the infertility group III including testicular and epididymal factors, but not in blood plasma. We conclude that the quantitative changes of metal components in the seminal plasma may have effects on not only spermatogenesis and sperm function, but also contribute to diagnostic parameter according to organ specificity of the metal in the male reproduction.

도시철도 차량 공기압축기 베어링의 진동 파라메터 분석을 통한 고장진단 연구

박남철(Nam-Cheol Park),구정서(Jeong-Seo Goo) 한국도시철도학회 2021 한국도시철도학회논문집 Vol.9 No.4

도시철도 5호선 전동차 공기압축기(Air Compressor) 정비주기는 4년이나, 베어링 고장예방을 위해 2년마다 분해 정비를 시행함으로써 가용성을 저하시키고 있어, 본 논문에서는 베어링 상태진단 방법을 제시함으로써 차량의 가용성 향상 방안을 제시하고자 하였다. 공기압축기는 1,750 rpm으로 회전하고 있으며, 발생되는 진동을 시간 도메인으로 측정한 RMS와 Crest Facter 크기로 이상여부를 확인하고 푸리에 변환된 베어링 주파수(BPFI, BPFO, BSF, FTF) 크기를 비교하여 결함 베어링을 확인하였다. 결함검지 알고리즘은 신품 베어링 진동크기를 기준으로 관측대상 진동 크기를 20초간 4회 비교하여 베어링 결함여부를 판단하였으며, 2개의 베어링 고장 모사시험결과 확률이 87.5%로 나타나 결함 베어링 검지 확률이 높음을 확인할 수 있었다. The maintenance cycle of the Air Compressor on Subway Line 5 is four years, and the availability is reduced by performing disassembly maintenance every two years to prevent bearing failures, so this paper suggested ways to improve the availability of vehicles. The air compressor rotates at 1,750 rpm, checks for abnormalities in the RMS and Crest Factor sizes measuring the generated vibration in the time domain, and compares the Fourier transformed bearing frequencies (BPFI, BPFO, BSF, FTF) sizes to confirm defects. The defect detection algorithm compared the vibration size to be observed four times for 20 seconds based on the vibration size of the new bearing to determine whether there is a bearing defect, and the probability of detecting the defective bearing was 87.5%.

도시철도차량 세브론 고무 특성 변화가 진동승차감 레벨에 미치는 영향 연구

박남철(Nam Cheol Park),구정서(Jeong Seo Koo) 한국기계가공학회 2016 한국기계가공학회지 Vol.15 No.2

The suspension system of a subway vehicle is composed of 1st and 2nd springs. The suspension system is the most important parameter in determining the vibration ride comfort. If the 1st suspension spring is designed as a spring with strong stiffness to improve the running stability at high speed, it causes vehicle vibrations. In this paper, by testing and analyzing changes of the characteristics of Chevron springs, which have been the primary suspension springs used for about 20 years, we study how changing the characteristics affects vehicle acceleration and ride comfort. The lateral and longitudinal vibrational ride comfort index levels were lower than the vertical ones. Therefore, as increasing the stiffness of Chevron springs has the greatest effect on the vertical vibrational ride comfort index level, a countermeasure for vertical vibration reduction is needed when the stiffness increases owing to aging. Finally, maintenance guidelines, including the replacement time for the Chevron rubber, were proposed based on these findings.

철도차량 현가장치 강성변화가 주행중 진동에 미치는 영향연구

박남철(Nam Cheol Park),구정서(Jeong Seo Koo),유원희(Won Hee You) 한국철도학회 2014 한국철도학회 학술발표대회논문집 Vol.2014 No.10

철도 차량의 현가장치는 1 차와 2 차 현가장치로 구성되어 있으며, 주행 중 진동에 영향을 미치는 중요한 요소이다. 특히, 현가장치에 있어서 강성은 설계단계에서 중요한 요소로서 강성(Stiffness)의 증가는 고속에서의 주행성능이 좋아지는 장점이 있는 반면에 주행 중 진동이 증가하는 요소로 작용된다. 본 연구에서는 서울도시철도 5 호선 차량의 1 차 현가 장치인 세브론 러버 스프링(Chevron Rubber Spring)의 강성(Stiffness)증가가 주행 중 진동에 미치는 영향 연구를 1 차 현가장치를 샘플링 하여 강성을 측정하였으며, 적정강성(2 kN/mm)에서 수직방향기준 0.7kN/mm (35%) 초과시 수직방향 최대 진동 가속도가 0.045g(58%), 횡방향 최대진동가속도가 0.008g(10%)증가되는 것을 확인하였다. A suspension system of subway vehicles is composed of 1<SUP>st</SUP>. and 2<SUP>nd</SUP>.spring. The suspension system is the most important parameter of running vibration. Application of the 1st. suspension with a strong stiffness is the main design direction in order to improve the running performance at a high speed, but it causes severe vibration problems of the vehicle. In this paper, it was studied how much the stiffness changes of the 1<SUP>st</SUP>. suspension in EMU(Line 5), which consists of chevron rubber springs, has effects on the vibration of the subway vehicle. We measured the chevron rubber spring stiffness and the vibration of the subway vehicle. We found out that if 35% (0.7kN/mm) of the vertical stiffness exceeded over the standard vertical spring stiffness (2.0kN/mm), the maximum vibration acceleration to the vertical and lateral directions increased by 0.045g (58%) and 0.008g(10%), respectively.

Acrobeads Test를 이용한 정자수정능의 평가

박영수,박남철,Park, Young-Soo,Park, Nam-Cheol 대한생식의학회 1996 Clinical and Experimental Reproductive Medicine Vol.23 No.1

The assessment of acrosomal status is important in evaluating the ability of sperm to fertilize the egg. The acrosomal status of sperm from 47 normal volunteers with proven fertility and 167 subfertile men with not to achieve pregnancy for at least 1 year were evaluated with Acrobeads test(FUSO Pharmaceutical Industries, Ltd, Japan) using immunobeads coated with MH61 monoclonal antibody, which is specific for acrosome-reacted sperm. The mean${\pm}$SD of acrobeads score in 47 volunteer group was $2.8{\pm}0.7$, of which 46(97.9%)cases were ${\geq}$ 2. The mean${\pm}$SD of acrobeads score in 167 subfertile group was $1.7{\pm}0.8$, of which 73(79.3%)cases were ${\leq}$ 1. The aerobe ads score in subfertile group were significantly lower(r=0.294, p<0.05) than those in volunteer group. In subfertile group, acrobeads score were well correlated with the sperm density and motility(r=0.275, r=0.281, p<0.01), but not with semen volume(r=0.16) and serum hormone level(FSH r=0.084, LH r=0.036, testosterone r=0.058, prolactin r=0.006 and estradiol r=0.060)(p>0.05). Of 63 subfertile cases with normozoospermia, 22(34.9%)cases showed 0 or 1 of acrobeads score, which means to accompany with a functional defect in spite of normal morphology. As a results, Acrobeads test is not only a technically simple sensitive procedure with good reproducibility in evaluating the sperm fertilizing capacity but also an useful in the evaluation of effectiveness in the treatment of infertility and the separation of acrosome-reacted sperm in the assisted reproductive technique.

비배우자간 인공수정이 권유된 남성불임환자의 의식조사

박현준,박남철,Park, Hyun-Jun,Park, Nam-Cheol 대한생식의학회 2003 Clinical and Experimental Reproductive Medicine Vol.30 No.4

Objectives: In determining to perform non-spousal artificial insemination by donor (AID) to an infertile married couple, infertile couple requires not only the thorough understanding of the medical procedure but also scrutinizing the effect, which it will have on the relationship of the family including the baby to be born itself. Materials and methods: 148 cases with non-curable male infertility were enrolled in this inquiry survey. The donor insemination questionnaire consists of 18-items which are assessing subjects' clinical properties, the background for AID practice, psychological traits, and long term influence. Results: Of the survey, 49 cases were returned (33.1%) and 10 cases (20.4%) of these gave birth after AID practice. The mean age of husbands and wives of the 49 cases were $34.6{\pm}4.2$ and $32.1{\pm}3.0$ yers old, respectively and the duration of marriage was 5 years and 4 months. In about half of the cases, AID was first suggested by husband and the decision was made by only the couple. The major reason for the operation was to form a complete family. In the item of the psychological effects, two-third of the couples felt anxiety related to the procedure which are mostly about the possible congenital or acquired deformity of baby. The AID was positively suggested in overall by all of recipients. After giving birth to a child, most couples felt positive about their decision. As a child grows up, about half of the couples felt the child as their own and expected not to tell of the AID. In overall, about 50% of couples presented satisfaction with the procedure. Conclusions: As the above results, various psychological impacts including anxiety about a child-to-be-born were accompanied to those who were recommended of AID. To overcome these problems, sufficient medical information and consultation about the course of selecting the donor and the whole procedures of AID should be provided beforehand.

20년간 정관정관문합술 1000례의 임상적 경험

서호경,박남철,Seo, Ho-Kyung,Park, Nam-Cheol 대한생식의학회 1998 Clinical and Experimental Reproductive Medicine Vol.25 No.2

Since the male sterilization (vasectomy) has been performed on a large scale as an accepted family planning in Korea on 1980s and this, in turn, has been followed by an increase in the number of patients requesting vasovasostomy. We studies 1000 consecutive cases of vasovasostomy performed from January 1975 to July 1995 in Pusan National University Hospital. In this report, we are going to present serial studies of vasovasostomy through which we attempted to find out what factors are of impotence in influencing the successful outcome of vasovasostomy operation. We inquired the operative results data through the questionnaire and telephone interview with survey of medical records. A total of 259 cases was excluded due to the loss of follow-up. The overall patency and pregnancy rates of 741 cases were 86.9% and 51.1%, respectively. The age of man at the time of anastomosis ranged from 23 to 57 years old with an average of 34.9. The most frequent reason for requesting vasovasostomy was the desire to have more children (43.4%). The average obstructive interval was 60.6 months with range from 1 to 264 months. If the obstructive interval had been less than 5 years patency rate was 92.4% and pregnancy rate 64.8%, but 6 years or more 84.1% and 48.5% (p<0.01, p<0.01). Patency and pegnancy rates according to intraoperative vas fluid were 93.1% and 62.8% for presence and 83.7% and 53.1% for absence (p<0.01, p<0.05). Patency and pregnancy rates according to histologically proven sperm granuloma at vasectomy site were 87.7% and 49.2% for presence and 86.9% and 50.6% for absence (p>0.05, p<0.05). Patency and pregnancy rates were not significantly different between microscopic standard vasovasostomy (88.4%, 64.3%) and modified vasovasostomy (89.5%, 56.3%)(p>0.05, p>0.05). Both patency and pregnancy rates according to level of anastomosis were 89.8% and 59.8% in cases of straight vas and 91.5%, 60.1% in cases of convoluted vas (p>0.05, p>0.05). Patency and pregnancy rates according to the kind of suture materials were 91.5% and 56.2% for absorbable, 91.0% and 64.2% for non-absorbable and 93.3% and 53.3% for absorbable plus non-absorbable, respectively (p>0.05, p<0.05). Thus it is suggested that the important factor influencing the success rate of vasovasostomy is the interval of obstruction and vasal ooze with surgical skills.

생체외 L-carnitine과 Acetylcarnitine의 정자지표 개선 효과

이완,박남철,Lee, Wan,Park, Nam-Cheol 대한생식의학회 2002 Clinical and Experimental Reproductive Medicine Vol.29 No.2

Objectives: To assess the scavenging effect of carnitine derivatives on oxidative damage to sperm during sperm processing, cryopreservation and thawing. Materials and Methods: Fresh semen samples from 20 normal healthy volunteers were collected by masturbation after at least 48 hours abstinence. After liquefaction of semen samples at room temperature, the specimens were diluted with sperm wash media (Ham's F-10, Life technologics) to a uniform density of $20{\times}10^6/ml$. L-carnitine or acetylcarnitine were added with various concentration of $0{\mu}M$, $10{\mu}M$, $30{\mu}M$ in semen sample or cryoprotectant. All specimens were cryopreservated at $-196^{circ}C$ $LN_2$ for 3 days. Sperm motility, vitality, fertilizing capacity, reactive oxygen species formation and the level of lipid peroxidation were analyzed by computer assisted semen analyzer, eosin-nigrosin stain, hypoosmotic swelling test, chemiluminescence and thiobarbituric acid method, respectively, during sperm processing, cryopreservation and thawing. Results: The sperm motility was only increased in proportion to the concentration of acetylcarnitine with no statistical significance (p>0.05). The sperm vitality was also significantly improved in proportion to the concentration of acetylcarnitine with statistical significance (p<0.05). The sperm fertilizing capacity was significantly increased in proportion to the concentration of L-carnitine and acetylcarnitine and reactive oxygen species generation and lipid peroxidation were significantly decreased with same fashion (p<0.05). On comparison of effects between L-carnitine and acetylcarnitine, acetylcarnitine was superior to L-carnitine on the improvement of sperm motility and vitality as well as the suppression of reactive oxygen species generation and lipid peroxidation. Conclusions: These results suggest that carnitine derivatives have a scavenging effect against oxidative damages during sperm processing, cryopreservation and thawing. Therefore, carnitine derivatives may be useful as an oral antioxidant in patients with male infertility due to increased ROS generation.