• Journal of the Society of Cosmetic Scientists of Korea
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• v.40 no.4
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• pp.413-421
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• 2014

Corticotropin-releasing factor (CRF) is involved in the stress response and there is increasing evidence that stress influences skin disease such as hair loss. In cultured human hair follicles, CRF inhibits hair shaft elongation, induces premature regression and promotes the apoptosis of hair matrix keratinocytes. We investigated whether CRF influences the dermal papilla cells (DPC) that play pivotal roles in hair growth and cycling. Human DPCs were treated with CRF, adrenocorticotropic hormone (ACTH) and cortisol, key stress hormones along the hypothalamic-pituitary -adrenal (HPA) axis for 1-24 h. Interestingly, CRF modulated the expression of cytokines related to hair growth (KGF, Wnt5a, $TGF{\beta}-2$, Nexin) and increased cAMP production in cultured DPCs. CRF receptors were down-regulated by negative feedback systems. Pretreatment of CRF receptor antagonists or protein kinase A (PKA) inhibitor prevented the CRF-induced modulation. Since the CRF induces proopiomelanocortin (POMC) expression through the cAMP/PKA pathway, we analyzed POMC mRNA. CRF stimulated POMC expression in cultured human DPCs, yet we were unable to detect ACTH levels by western blot. These results indicate that CRF operates within DPCs through CRF receptors along the classical CRF signaling pathway and CRF receptor antagonists could serve as potential therapeutic and cosmetic agents for stress-induced hair loss.

• Radiation Oncology Journal
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• v.32 no.3
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• pp.187-197
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• 2014

Purpose: We aimed to analyze the treatment outcome and long-term toxicity of 70 Gy hypofractionated intensity-modulated radiotherapy (IMRT) for localized prostate cancer using a customized rectal balloon. Materials and Methods: We reviewed medical records of 86 prostate cancer patients who received curative radiotherapy between January 2004 and December 2011 at our institution. Patients were designated as low (12.8%), intermediate (20.9%), or high risk (66.3%). Thirty patients received a total dose of 70 Gy in 28 fractions over 5 weeks via IMRT (the Hypo-IMRT group); 56 received 70.2 Gy in 39 fractions over 7 weeks via 3-dimensional conformal radiotherapy (the CF-3DRT group, which served as a reference for comparison). A customized rectal balloon was placed in Hypo-IMRT group throughout the entire radiotherapy course. Androgen deprivation therapy was administered to 47 patients (Hypo-IMRT group, 17; CF-3DRT group, 30). Late genitourinary (GU) and gastrointestinal (GI) toxicity were evaluated according to the Radiation Therapy Oncology Group criteria. Results: The median follow-up period was 74.4 months (range, 18.8 to 125.9 months). The 5-year actuarial biochemical relapse-free survival rates for low-, intermediate-, and high-risk patients were 100%, 100%, and 88.5%, respectively, for the Hypo-IMRT group and 80%, 77.8%, and 63.6%, respectively, for the CF-3DRT group (p < 0.046). No patient presented with acute or late GU toxicity ${\geq}$grade 3. Late grade 3 GI toxicity occurred in 2 patients (3.6%) in the CF-3DRT group and 1 patient (3.3%) in the Hypo-IMRT group. Conclusion: Hypo-IMRT with a customized rectal balloon resulted in excellent biochemical control rates with minimal toxicity in localized prostate cancer patients.

• Korean Journal of Optics and Photonics
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• v.31 no.5
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• pp.223-230
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• 2020

In this paper, we have studied the characteristics of stimulated Brillouin scattering (SBS) and mode instability (MI) in a ytterbium-doped polarization-maintaining fiber laser with master oscillator power amplifier configuration. We measured the laser output power and back-reflection spectrum for a variety of ytterbium-doped fibers and seed lights, to investigate the power-scaling limits of fiber lasers. By optimizing the laser structure, we demonstrated an all-fiber high-power polarization-maintaining fiber laser with near-diffraction-limited beam quality. The output power of 1.5 kW was achieved with a linewidth of 10 GHz, generated by pseudo-random binary sequence (PRBS) phase modulation. The beam quality M² was about 1.15 at the maximum output power. The polarization extinction ratio (PER) was greater than 17 dB.

• Journal of Broadcast Engineering
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• v.14 no.6
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• pp.733-741
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• 2009

The design rule of digital communication systems is the reliable data transmission with high spectral efficiency and minimum allowable power. This paper suggests the method that saves the average power by implementing a multi-dimensional constellation in case of multi-carrier communication system. By using multi-dimensional constellations we can relocate constellation points in the form of a sphere. If we simply convert the two-dimensional QAM modulation into multi-dimensional QAM, constellation points of 2 N dimensional cube form are made up. Relocating outermost constellation points of 2 N dimensional cube form into low energy constellation points, the constellation of the 2 N-dimensional sphere form is made up which decreases power consumption. In this paper, the multi-dimensional constellations of 2 N-dimensional sphere form are designed from 16-QAM to 2,048-QAM, and power reductions are obtained by comparing constellations of 2-dimensional QAMs and multi-dimensional constellations of 2 N-dimensional sphere form. The result shows that the average power consumption of higher dimensional constellations increases, because the more a dimension elevates, the more the relocatable constellation points increase. But, the increment of the average power savings decreases as the a dimension elevates. The transmission of the data by using multi-dimensional constellations of the sphere form is effective to save the average power consumption with little hardware complexity.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.42 no.2 s.332
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• pp.61-74
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• 2005

Digital Multimedia Broadcasting(DMB) is a reliable multi-service system for reception by mobile and portable receivers. DMB system allows interference-free reception under the conditions of multipath propagation and transmission errors using COFDM modulation scheme, simultaneously, needs powerful channel error's correction ability. Viterbi Decoder for DMB receiver uses punctured convolutional code and needs lots of computations for real-time operation. So, it is desired to design a high speed and low-power hardware scheme for Viterbi decoder. This paper proposes a combined add-compare-select(ACS) and path metric normalization(PMN) unit for computation power. The proposed PMN architecture reduces the problem of the critical path by applying fixed value for selection algorithm due to the comparison tree which has a weak point from structure with the high-speed operation. The proposed ACS uses the decomposition and the pre-computation technique for reducing the complicated degree of the adder, the comparator and multiplexer. According to a simulation result, reduction of area $3.78\%$, power consumption $12.22\%$, maximum gate delay $23.80\%$ occurred from punctured viterbi decoder for DMB system.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.43 no.1 s.307
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• pp.45-52
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• 2006

In this paper, authors propose a step-up converter of pulse width modulation (PWM) and power factor correction (PFC) by using a novel loss-less snubber. The proposed converter for a discontinuous conduction mode (DCM) eliminates the complicated circuit control requirement and reduces the size of components. The input current waveform in the proposed converter is got to be a sinusoidal form of discontinuous pulse in proportion to magnitude of ac input voltage under the constant duty cycle switching. Thereupon, the input power factor is nearly unity and the control method is simple. In the general DCM converters, the switching devices are fumed-on with the zero current switching (ZCS), and the switching devices must be switched-off at a maximum reactor current. To achieve a soft switching (ZCS and ZVS) of the switching turn-off, the proposed converter is constructed by using a new loss-less snubber which is operated with a partial resonant circuit. The result is that the switching loss is very low and the efficiency of converter is high. Some simulative results on computer and experimental results are included to confirm the validity of the analytical results.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.43 no.1 s.343
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• pp.7-12
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• 2006

In this study, we developed irreversible and stable micro-size ferromagnetic structures utilizing hydrogenation and electron-beam lithography processes. The compositionally modulated (CM) Fe-Zr thin films that had average compositions $Fe_XZr_{100-x}$ with $x=65-85\%$ modulation periods of similar to 1 nm, and total thicknesses of similar to 100 m were prepared. The magnetic properties of CM Fe-Zr thin films were measured using a SQUID magnetometer, VSM and B-H loop tracer. After hydrogenation, the CM films exhibited larger magnetic moment increases than similar homogeneous alloy films for all compositions and かey showed largest increase in $Fe_{80}Zr_{20}$ composition. After aging in air at $300^{\circ}K$ the hydrogenated $Fe_{80}Zr_{20}$ CM films showed much larger magnetic moment increases, indicating that they relax to a stable, irreversible, soft magnetic state. The selective hydrogenation through electron-beam lithographed windows were performed after the circle shaped windows were prepared on $Fe_{80}Zr_{20}$ CM films by electron beam lithography. The hydrogenation through electron-beam resist and W lithographic techniques give a $49\%$ magnetic moment increase. This method can be applied to nano scale structures.

• Journal of Acupuncture Research
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• v.19 no.5
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• pp.219-233
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• 2002

면역억제활성이 알려진 Cerves korean TEMMINCK var. manchur-icus Swinhoe(Nokyong) 약침(CPH)은 다모 뿔의 녹용을 열수추출한 용액이다. 본 연구에서는 녹용 약침의 효과를 adjuvant 유발 관절염 실험용쥐를 이용하여 골체, 골강도 및 골대체율의 감소를 평가하였다. 위의 골 대사 관련 검정실험을 위하여 6주령의 암컷 실험용쥐에 20일간 약물투여를 실시하였다. 실험적인 관절염유발은 실험용쥐의 뒤쪽 다리에 Adjuvant를 주사하여 유발시킨 결과, 요부의 골 무기질함량과 밀도(BMC, BMD) 그리고 압축강도는 관절염 실험용쥐에서 감소되었다. 10일 경과 후 골형성도(BFR/BS, BFR/BV)의 조직형태학적 기준척도인 혈청 osteocalcin 수가 정상대조군과 비교해 볼 때 현저하게 감소되었다. 그러나, 몸무게로 나눈 BMC치는 관절염 유발군과 정상군 사이에 큰 차이가 보이지 않았다. 그리고 골무기질 함량은 정상군에 비해 감소하지 않았다. 20일 경과후 몸무게로 나누거나 나누지 않은 BMC치 모두, 관절염 군에서 요부 몸체의 골무기질 함량과 강도가 정상군과 비교해 볼 때 현저하게 감소되었다. 잔존 소주(小柱)의 무기질 침착 표면은 현저하게 감소하였으며 파골 세포의 수는 증가하였다. 초기부터 매일 Shinsu(B23)에 CPH 약침 투여(10, 20, $50{\mu}g/kg$)는 20일 경과후 만성적인 다리 부종을 현저하게 방지하였으며, 골 무기질함량, 골강도 및 소주골 형성등의 감소와 파골세포수 증가도 완화하였다. Adjuvant주사로 장애를 받았던 연령대비 요부 길이 증가도 유지되었다. 이러한 결과는 Adjuvant에 의한 관절염 실험용쥐의 2차적인 골관절염에서 충분히 요추 몸체뼈와 강도 감소를 나타내기 위해서는 적어도 20일이 필요하다는 것을 제시하였다. 본 결과로부터 CPH가 실험용쥐의 관절염에 대한 골체, 골강도 및 골대체율을 조절하는데 유효하게 작용하고 있음을 알 수 있었다.

• The Korea Journal of Herbology
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• v.30 no.4
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• pp.109-119
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• 2015

Objectives : The aim of this study was to evaluate the effect of aqueous extracts of Mume Fructus(MF) on the 6-n-propyl-2-thiouracil(PTU)-induced rat hypothyroidism.Methods : Aqueous extracts of MF(yield = 19.38%) were administered, once per day for 42 days from 2 weeks before starting of PTU treatment as an oral dose of 300 and 150 ㎎/㎏(body weight), and hypothyroidism was induced by daily subcutaneous treatment of PTU 10 ㎎/㎏ for 28 days. The changes in the body weight, thyroid gland weights, liver weight, serum levels of thyroid hormone-thyroid stimulating hormone(TSH), tri-iodothyronine(T₃) and thyroxine(T₄), total cholesterol, low density lipoprotein(LDL), high density lipoprotein(HDL) and triglyceride (TG), aspartate aminotransferase(AST), alanine aminotransferase(ALT), liver antioxidant defense system-lipid peroxidation, H₂O₂, superoxide dismutase(SOD) and catalase(CAT) were examined with histopathology of thyroid glands and liver.Results : Results were compared with LevoT₄0.5 ㎎/㎏ treated rats. MF extracts recovered from the decreases in the body weight, liver weight, T₃and T₄, TG, liver CAT activities as results of PTU treatment. And MF extracts recovered from the increases of thyroid gland weights, TSH, HDL contents, liver H₂O₂, AST as results of PTU treatment. In addition, these PTU-induced histopathological changes in thyroid glands and liver related to hypothyroidism were dramatically decreased by treatment of both different dosages of MF extract, respectively.Conclusions : According to the above results, it is suggested that MF extracts have advantageous effects on the thyroid hormone productions with beneficial effects on the hypothyroidism related liver injuries mediated by the modulation on the antioxidant system.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.10
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• pp.4353-4358
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• 2014

Background: PI3/AKT and NF-kB signaling pathways are constitutively active in acute myeloid leukemia and cross-talk between the two has been shown in various cancers. However, their role in acute myeloid leukemia has not been completely explored. We therefore used cell penetrating inhibitor peptides to define the contributions of AKT and NF-kB to survival and multi drug resistance (MDR) in HL-60 cells. Materials and Methods: Inhibition of AKT and NF-kB activity by AKT inhibitor peptide and NBD inhibitor peptide, respectively, resulted in decreased expression of mRNA for the MDR1 gene as assessed by real time PCR. In addition, treatment of HL-60 cells with AKT and NBD inhibitor peptides led to inhibition of cell viability and induction of apoptosis in a dose dependent manner as detected by flow cytometer. Results: Finally, co-treatment of HL-60 cells with sub-optimal doses of AKT and NBD inhibitor peptides led to synergistic apoptotic responses in AML cells. Conclusions: These data support a strong biological link between NF-kB and PI3-kinase/AKT pathways in the modulation of antiapoptotic and multi drug resistant effects in AML cells. Synergistic targeting of these pathways using NF-kB and PI3-kinase/AK inhibitor peptides may have a therapeutic potential for AML and possibly other malignancies with constitutive activation of these pathways.