• 전기화학회지
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• 제15권1호
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• pp.12-18
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• 2012

다양한 응용분야에서 활용될 수 있는 고체고분자연료전지의 경우 현재 상용화에 가장 큰 걸림돌이 되고 있는 것이 고가의 백금 촉매이다. 따라서 특히 최근 들어 산소환원반응에서 백금을 대체하는 물질을 개발하기 위한 연구가 전세계적으로 확산되고 있다. 그러나 촉매 개발 시 경제성 관점 외에 내구성도 고려해야 하는데, 이런 관점에서 백금과 유사한 물성과 활성이 기대되는 백금족 원소들이 한 대안이 될 것이다. 가장 백금과 유사한 물성, 활성을 나타내는 팔라듐과 칼코겐화물 형태의 루테늄이 지금까지 가장 많이 연구가 되었으며 상대적으로 이리듐, 로듐, 오스뮴은 산소환원 촉매로 많은 연구가 되지 않았다. RDE (rotating disk electrode)를 이용한 반쪽전지 실험이나 연료전지 MEA (membrane electrode assembly) 운전을 통하여 백금과 활성을 비교해보면 팔라듐 계열의 비백금 촉매가 가장 백금에 가까운 활성을 나타내고 있음을 알 수 있다. 이 논문에서는 각 백금족 원소들 기반의, 현재까지 문헌상으로 보고된 촉매조성들을 분석하여 비백금 산소환원 촉매 개발에 도움이 되고자 한다.

• Asian Pacific Journal of Cancer Prevention
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• 제13권4호
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• pp.1333-1340
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• 2012

Epithelial ovarian cancer represents the most lethal gynecological cancer, and the high mortality rate makes this malignancy a major health concern. Poor prognosis results from an inability to detect ovarian cancers at an early, curable stage, as well as from the lack of an effective therapy. Thus, effective and novel strategies for prevention and treatment with non-toxic agents merit serious consideration. Resveratrol, obtained from grapes, berries, peanuts and red wine, has been shown to have a potent growth-inhibitory effect against various human cancer cells as well as in in vivo preclinical cancer models. The objective here was to evaluate potential antitumor effects of resveratrol in both in vitro and in vivo NuTu-19 ovarian cancer models. In vitro an invasion assay was performed. After 48 h, the numbers of viable cells that invaded the extracellular matrix layer were reduced by 94% with resveratrol in comparison to control. For the in vivo anti-tumor assessment, 10 rats were injected with NuTu-19 cells into the ovarian bursa. Thereafter, half were provided with a diet mixed with a dose of 100 mg resveratrol/kg body weight/day for 28 days. Following sacrifice, anticancer effects were assessed by histological evaluation of ovarian as well as surrounding tissues, and immunohistochemical detection of cell proliferation and apoptosis, but there were no observable differences between the control and resveratrol-treated groups for any of the biological endpoints. While resveratrol is effective in suppressing the in vitro cellular invasion of NuTu-19 ovarian cancer cells, these effects do not appear to impact on in vivo NuTu-19 ovarian cancers in rats.

• Asian Pacific Journal of Cancer Prevention
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• 제14권7호
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• pp.4101-4106
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• 2013

Alterations of cyclin D1, one of the main regulators of the cell cycle, are known to be involved in various cancers. The CCDN1 G870A polymorphism causes production of a truncated variant with a shorter half-life and thus thought to impact the regulatory effect of CCDN1. The aim of the present study was to contribute to existing results to help to determine the prognostic value of this specific gene variant and evaluate the role of CCDN1 G870A polymorphism in brain cancer susceptibility. A Turkish study group including 99 patients with primary brain tumors and 155 healthy controls were examined. Genotypes were determined by polymerase chain reaction-restriction fragment length polymorphism analysis. The CCDN1 genotype frequencies in meningioma, glioma and control cases were not significantly different (p>0.05). No significant association was detected according to clinical parameters or tumor characteristics; however, a higher frequency of AG genotype was recorded within patients with astrocytic or oligoastrocytic tumors. A significant association between AG genotype and gliobilastoma multiforme (GBM) was recorded within the patients with glial tumors (p value=0.048 OR: 1.87 CI% 1.010-3.463). According to tumor characteristics, no statistically significant difference was detected within astrocytic, oligoasltrocytic tumors and oligodentrioglias. However, patients with astrocytic astrocytic or oligoastrocytic tumors showed a higher frequency of AG genotype (50%) when compared to those with oligodendrioglial tumors (27.3%). Our results indicate a possible relation between GBM formation and CCDN1 genotype.

• Animal cells and systems
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• 제3권4호
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• pp.385-391
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• 1999

Changes in the levels of prostaglandian F$_{2a}$ (PGF$_{2a}$) and E$_2$ (PGE$_2$) in culture medium during in vitro ovulation of Rana dybowskii follicles were examined. The ovulation was induced by frog pituitary homogenate (FPH) or TPA (12-O-tetradecanoylphorbol-13-acetate, a protein kinase activator) and the levels of PGs were measured by radioimmunoassay. When the ovarian follicles were cultured, only a few oocytes were ovulated by 12 h, but half of them were ovulated by 24 h in response to FPH, whereas around 30% of oocytes were ovulated by 12 h and maximum ovulation (around 50%) occurred by 24 h in response to TPA. Without any stimulation (control), no ovulation occurred. TPA elevated the level of PGF$_{2a}$ to high levels when compared to control (basal levels), but the increase by FPH was less evident. Likewise, the levels of PGE$_2$ increased markedly in response to TPA, but rather decreased by FPH treatment. Interestingly, PGF$_{2a}$ induced ovulation but PGE$_2$ suppressed FPH- or PGF$_{2a}$-induced oocyte ovulation. Basal levels of PGs Increased steadily during culture. When theca/epithelium (THEP) layer and granulosa cell-enclosed oocytes (GCEOs) were separated by microdissection and cultured independently, higher levels of both PGs were secreted by THEP than by GCEOS. Synthesis of PGs by follicle or follicular components was strongly suppressed by exogenous cAMP or indomethacin. These results suggest that: 1) PGF$_{2a}$ plays an important role in Rana ovulation, 2) protein kinase C is involved in PGs production, and 3) thecal epithelium layer is responsible for the PGs production in Rana.

• 전자공학회논문지C
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• 제36C권4호
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• pp.31-43
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• 1999

본 논문의 주요 목표는 고성능 SVP(Stack-based Video Processor)를 설계하는 것이다. SVP는 과거에 제안된 스택 머신과 영상 프로세서의 최적의 측면만을 선택함으로써 더 좋은 구조를 갖도록 하는 포괄적인 구조이다. 본 구조는 객체 지향형 프로그램의 소규모의 많은 서브루틴을 가지고 있기 때문에 스택 버퍼를 갖는 준범용 S-RISC(Stack-based Reduced Instruction Set Comuter)를 이용하여 객체 지향형 영상 데이터를 처리한다. 그리고 MPEG-4의 반화소 단위 처리와 고급 모드 움직임 보상, 움직임 예측, SA-DCT(Shape Adaptive-Discrete Cosine Transform)가 가능하며, 절대값기, 반감기를 가지고 있어서 부호화하기로 확장할 수 있도록 하였다. SVP는 0.6㎛ 3-메탈 계층 CMOS 표준 셀 기준을 이용하여 설계되었으며, 110K 로직 게이트와 12Kbit SRAM 내부 버퍼로 이루어지고 50 MHz의 동작 속도를 가진다 . MPEG-4의 VLBL(Very Low Bitrate Video) 최대 전송율인 QCIF 15fps(frame per second)로 영상 재생 알고리즘을 수행한다.

• Asian Pacific Journal of Cancer Prevention
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• 제15권20호
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• pp.8715-8718
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• 2014

Background: ABVD (doxorubicin, bleomycin, vinblastine (Vb) and dacarbazine) is the standard regimen in Hodgkin's lymphoma (HL).Vincristine (O) is a mitotic spindle agent like Vb. We aimed to evaluate the efficacy and safety of O as a part of ABOD in HL. Materials and Methods: Patients who had ABOD were enrolled. Stage I-II HL were evaluated for unfavorable risk factors according to NCCN. National Cancer Institute Common Toxicity Criteria was used for toxicity. Results: Seventy-nine HL patients in our center between 2003 and 2007 were evaluated retrospectively. Median follow-up was 54 months. Most of the patients were male in their third decade. Median ABOD cycles were 6 (2-8). Primary refractory disease rate was 17.7% whereas it was 5.1% for early relapse and 5.1% for late relapse disease. Response rates were as 82.3% for complete response, 11.4% for partial response, 5.1% for stable disease and 1.3% for progressive disease. Half of relapsed patients had autologous stem cell transplantation. Estimated 5-year failure-free survival was 71% and significantly longer in early stage patients without risk factors, bulky disease or radiotherapy (RT) (p=0.05, p<0.0001, p=0.02; respectively). Estimated 5-year overall survival was 74% and significantly longer in those who had no RT (p=0.001). Dose modification rate was 5.1% and chemotherapy delay rate was 19%. There were no toxicity-related deaths. Conclusions: ABOD seems to be effective with managable toxicity in HL, even in those with poor prognostic factors.

• Asian Pacific Journal of Cancer Prevention
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• 제15권5호
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• pp.2069-2074
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• 2014

Purpose: To appraise the frequency of cervical cytological abnormalities in a population at normal risk via analysing the archive records of cytology for the period of approximately 9,5 years, comparing them with patient demographic charecteristics, and discuss the results for women under age of 35. Materials and Methods: A total of 32,578 cases of Pap smears were retrieved and analysed from our archive included the Pap tests performed between January 2001 and April 2010 at the Early Cancer Screening, Diagnosing and Education Center by the consent of three pathologists via utilizing the Bethesda System Criteria 2001 and the results were compared with some demographical characteristics. Results: Our rate of the cervical cytological abnormality was 1.83%, with ASCUS in 1.18%, LSIL in 0.39, HSIL in 0.16%, AGUS in 0.07%, squamous cell carcinoma in 0.02%, and adenoarcinoma in 0.006%. Cytological abnormalities were detected mostly in those with higher age, lower parity, and premenopausal period whereas the smoking status was without influence. Bacterial vaginosis (5.6%) was the most frequent infectious finding (Candida albicans 2.7%; Actinomyces sp. 1.3%; and Trichomonas vaginalis 0.2%) detected on the smears. The rate of abnormal cervical cytology was 9.5% among the women aged between 30-34. Conclusions: Early detection of the cervical abnormalities by means of the regular cervical cancer screening programmes is useful to attenuate the incidence, mortality, and morbidity of cervical cancer. Our prevalence of the cytological abnormalities was much lower than the one in Western populations in general but very similar to those reported from other Islamic countries that may be explained by the conservative lifestyle and the lower prevalence of HPV in Turkey. A remarkable rate of abnormal cervical cytology of women aged 30-34 was pointed out in the present study.

• ALGAE
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• 제18권4호
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• pp.281-288
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• 2003

To study the environmental features causing a bloom of the novel dinoflagellate Heterocapsa circularisquama (Dinophyceae), hydrographic and chemical aspects were measured in the Uranouchi Bay, Kochi Prefecture, Japan, from January to December, 1997. The cell density of H. circularisquama increased rapidly in early October, and dropped sharply in mid-October. Growth rate of H, circularisquama during bloom period appeared 1.50 division day$^{-1}$ under high water temperature (25$^{\circ}C$) and salinity (32 psu) conditions. Althought the result from hydrographic aspect indicated good condition for their growth, dissolved inorganic phosphorus (DIP) concentration in surface layer before bloom formation was less than 0.70uM, which is lower than their half saturation constant(Ks). Dissolved inorganic nitrogen(DIN): DIP ratio was > 30, indicating potential P-limitation. However, before bloom formation period of H. circularisquama, DIP concentrations were high in bottom layer (> 4.0 uM). Some studies reported that H. circularisquama had the ability to migrate vertically and to utilize dissolved organic phosphorus (DOP). Thus, DIP in bottom layer might have been utilized by H. circularisquama for their growth.DOP might have weakly affected their growth because of low reactive DOP concentrations owing to low DOP concentration (ca. 0.39 uM). Thus, if nutrient condition of bottom layer in Uranuchi Bay is not improved, the outbreaks of H. circularisquama red tides may became an annual feature.

• Asian Pacific Journal of Cancer Prevention
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• 제13권10호
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• pp.4931-4933
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• 2012

Objective: To determine the diagnostic performance of hematuria as a screening test for urinary bladder infiltration in cervical cancer patients with a prospective study design. Materials and Methods: Newly diagnosed cervical cancer patients at Srinagarind hospital from 14 June 2011 to 30 April 2012 were enrolled in this study. We collected midstream urine samples for urinalysis from every patient before routine cystoscopic exam for clinical staging. The presence of 3 or more red blood cells (RBCs) per high power field was defined as positive for hematuria. A two-by-two table was used to determine the diagnostic performance of hematuria to detect urinary bladder mucosal infiltration using cystoscopy and biopsy as the gold standard. Result: A total of 130 were patients included, 54 of which (41.5%) had hematuria. Of these, four patients (3.08%) had pathological report from cystoscopic biopsy confirmed metastatic squamous cell carcinoma. The sensitivity, specificity, PPV, NPV, and accuracy of hematuria as a screening test to detect urinary bladder mucosal infiltration of cervical cancer were 100%, 60.3%, 7.4%, 100%, and 61.5%, respectively. There was no single case of urinary bladder mucosal infiltration in patients initially staged less than stage III. Conclusions: Hematuria can be used as a screening test to detect urinary bladder mucosal infiltration of cervical cancer. This can reduce the number of cervical cancer patients who really need to undergo cystoscopy as a staging procedure to less than half and to less than 20% if stage III or more were included without missing a single case of urinary bladder mucosal infiltration.

• 멤브레인
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• 제18권1호
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• pp.75-83
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• 2008

본 연구에서는 Polyethylene (PE, Asahi) 이차전지용 막의 표면불소화를 통해 기계적 강도 및 열적 안정성과 고출력에서의 안정성을 높이기 위한 연구를 실시하였다. 전자주사현미경(scanning electron microscope, SEM), 접촉각(contact angle)을 통하여 불소가스 노출시간에 따른 막의 표면과 구조의 변화를 관찰하고, 인장강도와 표면 친수성 실험을 통하여 막의 기계적 물성을 확인하였다. 제조된 막의 전기화학적 특성을 확인하기 위하여 충/방전 실험, 수명특성. 고율방전시험을 실시하여 고출력에서 온도에 대한 안정성이 향상되었음을 확인하였다.