MONTE CARLO SIMULATION FOR CORRECTION OF IONIZATION CHAMBER WALL

Kurosawa, Tadahiro,Takata, Nobuhisa,Koyama, Yasuji Korean Association for Radiation Protection 2001 방사선방어학회지 Vol.26 No.3

In precise measurement of air kerma with cavity ionization chambers, the effect of wall attenuation and scatter are corrected by Kwall and that of nonuniformity by Knu. Using the EGS4 code, we calculated these two correction factors. Correction factors calculated for two different-sized cylindrical ionization chamber differ by up to 0.7% from those obtained by measurements.

Comprehensive Identification of Tumor-associated Antigens via Isolation of Human Monoclonal Antibodies that may be Therapeutic

Kurosawa, Yoshikazu The Korean Association of Immunobiologists 2009 Immune Network Vol.9 No.1

Although the success of trastuzumab and rituximab for treatment of breast cancer and non-Hodgkins lymphoma, respectively, suggests that monoclonal antibodies(mAbs) will become important therapeutic agents against a wider range of cancers, useful therapeutic Abs are not yet available for the majority of the human cancers because of our lack of knowledge of which antigens (Ags) are likely to become useful targets. We established a procedure for comprehensive identification of such Ags through the extensive isolation of human mAbs that may be therapeutic. Using the phage-display Ab library we isolated a large number of human mAbs that bind to the surface of tumor cells. They were individually screened by immunostaining, and clones that preferentially and strongly stained the malignant cells were chosen. The Ags recognized by those clones were isolated by immunoprecipitation and identified by mass spectrometry(MS). We isolated 2,114 mAbs with unique sequences and identified 25 distinct Ags highly expressed on several carcinomas. Of those 2,114 mAbs 434 bound to specifically to one of the 25 Ags. I am going to discuss how we could select proper target Ags for therapeutic Abs and candidate clones are therapeutic agents.

Promotion of grain growth in NiFe₂O₄ by annealing with oleic acid

Kurosawa, R.,Suzuki, T.,Nakayama, T.,Suematsu, H.,Niihara, K.,Jeong, Y.K.,Kim, K.H. Elsevier 2012 CURRENT APPLIED PHYSICS Vol.12 No.suppl2

For investigation of the grain-size dependence on magnetization, NiFe<SUB>2</SUB>O<SUB>4</SUB> nanoparticles were heated at 440 <SUP>o</SUP>C, 600 <SUP>o</SUP>C, 800 <SUP>o</SUP>C, and 1000 <SUP>o</SUP>C with and without oleic acid. It was recognized that the median diameter (D<SUB>50</SUB>) increased from 5.9 to 145.9 nm by the heat treatments from 440 to 1000 <SUP>o</SUP>C. In addition, it was confirmed that NiFe<SUB>2</SUB>O<SUB>4</SUB> nanoparticles after the heat treatment with oleic acid at 600 <SUP>o</SUP>C have higher grain growth rate than that after only heat treatment without oleic acid. It was deduced that NiFe<SUB>2</SUB>O<SUB>4</SUB> was dissolved in oleic acid, so that sintering speed became fast. From these results, it was concluded that the formally observed saturation magnetization increase in heat treated NiFe<SUB>2</SUB>O<SUB>4</SUB> nanoparticles with oleic acid was caused partly by grain growth enhancement with the presence of oleic acid.

Prompt gamma detection for range verification in proton therapy

Shunsuke Kurosawa,Hidetoshi Kubo,Kazuki Ueno,Shigeto Kabuki,Satoru Iwaki,Michiaki Takahashi,Kojiro Taniue,Naoki Higashi,Kentaro Miuchi,Toru Tanimori,김도균,김종원 한국물리학회 2012 Current Applied Physics Vol.12 No.2

It is an on-going challenge to verify the proton range in situ during proton therapy. Since the protons stop in target tissue, measurement of gamma-rays emitted either promptly from nuclear de-excitation or in pair from positron annihilation is the feasible method to monitor the proton range in-vivo. Using the technique of gamma collimation, we empirically demonstrated that the proton range and prompt gamma distribution are well correlated in the therapy energy range, and that measuring prompt gammas is a viable method for the clinical application. However, this collimation technique appears not to be applicable to passively scattered proton beams. The device chosen for gamma imaging in 2D is an electron tracking Compton camera, which images single-emission photons employing a gas chamber to induce Compton scattering. Images of prompt gammas were attained at the proton beam energy of 140 MeV. Measurements showed that gamma image in the energy range of 800e2000 keV provides a better match with the proton range compared to the image by lower energy gammas.

MONTE CARLO SIMULATION FOR CORRECTION OF IONIZATION CHAMBER WALL

Tadahiro, Kurosawa,Nobuhisa, Takata,Yasuji, Koyama 대한방사선 방어학회 2001 방사선방어학회지 Vol.26 No.3

In precise measurement of air kerma with cavity ionization chambers, the effect of wall attenuation and scatter are corrected by Kwall and that of nonuniformity by Knu. Using the EGS4 code, we calculated these two correction factors. Correction factors calculated for two different-sized cylindrical ionization chamber differ by up to 0.7% from those obtained by measurements.

Comprehensive Identification of Tumor-associated Antigens via Isolation of Human Monoclonal Antibodies that may be Therapeutic

Yoshikazu Kurosawa 대한면역학회 2009 Immune Network Vol.9 No.1

Although the success of trastuzumab and rituximab for treatment of breast cancer and non-Hodgkins lymphoma, respectively, suggests that monoclonal antibodies (mAbs) will become important therapeutic agents against a wider range of cancers, useful therapeutic Abs are not yet available for the majority of the human cancers because of our lack of knowledge of which antigens (Ags) are likely to become useful targets. We established a procedure for comprehensive identification of such Ags through the extensive isolation of human mAbs that may be therapeutic. Using the phage-display Ab library we isolated a large number of human mAbs that bind to the surface of tumor cells. They were individually screened by immunostaining, and clones that preferentially and strongly stained the malignant cells were chosen. The Ags recognized by those clones were isolated by immunoprecipitation and identified by mass spectrometry (MS). We isolated 2,114 mAbs with unique sequences and identified 25 distinct Ags highly expressed on several carcinomas. Of those 2,114 mAbs 434 bound to specifically to one of the 25 Ags. I am going to discuss how we could select proper target Ags for therapeutic Abs and candidate clones as therapeutic agents. Although the success of trastuzumab and rituximab for treatment of breast cancer and non-Hodgkins lymphoma, respectively, suggests that monoclonal antibodies (mAbs) will become important therapeutic agents against a wider range of cancers, useful therapeutic Abs are not yet available for the majority of the human cancers because of our lack of knowledge of which antigens (Ags) are likely to become useful targets. We established a procedure for comprehensive identification of such Ags through the extensive isolation of human mAbs that may be therapeutic. Using the phage-display Ab library we isolated a large number of human mAbs that bind to the surface of tumor cells. They were individually screened by immunostaining, and clones that preferentially and strongly stained the malignant cells were chosen. The Ags recognized by those clones were isolated by immunoprecipitation and identified by mass spectrometry (MS). We isolated 2,114 mAbs with unique sequences and identified 25 distinct Ags highly expressed on several carcinomas. Of those 2,114 mAbs 434 bound to specifically to one of the 25 Ags. I am going to discuss how we could select proper target Ags for therapeutic Abs and candidate clones as therapeutic agents.

Ge Fraction Dependence of Al-Induced Crystallization of SiGe at Low Temperatures

Masashi Kurosawa,Yoshitaka Tsumura,Taizoh Sadoh,Masanobu Miyao 한국물리학회 2009 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.54 No.1

Al-induced crystallization of Si<SUB>1-x</SUB>Ge<SUB>x</SUB> films (x = 0 - 0.5) has been investigated by using amorphous SiGe (a-SiGe)/Al structures to realize polycrystalline SiGe (poly-Si) layers on insulating lms at low temperatures. For the Si sample, poly-Si oriented to the (111) direction was formed after annealing (450 ℃, 20 h) and inversion of Si/Al layers occurred completely. For Si<SUB>1-x</SUB>Ge<SUB>x</SUB> samples (x > 0), the layer exchange occurred in partial areas and poly-SiGe with the (111) orientation was grown only in the exchanged areas. The Ge fractions of the crystallized SiGe were almost the same as those of the initial a-SiGe layers. The diameters of the crystallized areas decreased from ∼100 (x = 0) to ∼30 μm (x = 0.5) with increasing Ge fraction. This technique can be utilized for the formation of high-quality poly-SiGe at low temperatures. Al-induced crystallization of Si<SUB>1-x</SUB>Ge<SUB>x</SUB> films (x = 0 - 0.5) has been investigated by using amorphous SiGe (a-SiGe)/Al structures to realize polycrystalline SiGe (poly-Si) layers on insulating lms at low temperatures. For the Si sample, poly-Si oriented to the (111) direction was formed after annealing (450 ℃, 20 h) and inversion of Si/Al layers occurred completely. For Si<SUB>1-x</SUB>Ge<SUB>x</SUB> samples (x > 0), the layer exchange occurred in partial areas and poly-SiGe with the (111) orientation was grown only in the exchanged areas. The Ge fractions of the crystallized SiGe were almost the same as those of the initial a-SiGe layers. The diameters of the crystallized areas decreased from ∼100 (x = 0) to ∼30 μm (x = 0.5) with increasing Ge fraction. This technique can be utilized for the formation of high-quality poly-SiGe at low temperatures.

RDIU-Net: Lightweight Medical Image Segmentation Network

Juon Kurosawa,Armagan Elibol,Nak Young Chong 제어로봇시스템학회 2023 제어로봇시스템학회 국제학술대회 논문집 Vol.2023 No.10

공업화학,촉매/반응공학 : 플라즈마 중합 폴리스티렌막을 피복한 수정진동자 가스센서의 응용

흑택무 ( Shigeru Kurosawa ),애택수신 ( Hidenobu Aizawa ),한대상 ( Dae Sang Han ),송성훈 ( Seong Hun Song ),김영한 ( Sang Mok Chang ),장상목 한국화학공학회 2003 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.41 No.2

Effects of Val-Pro-Pro and Ile-Pro-Pro on Nondipper Patients: A Preliminary Study

Mari Takahashi Kurosawa,Yasunori Nakamura,Naoyuki Yamamoto,Kazuhisa Yamada,Toshiro Iketani 한국식품영양과학회 2011 Journal of medicinal food Vol.14 No.5

Much clinical evidence on the antihypertensive effects of the milk-derived antihypertensive peptides Val-Pro-Pro and Ile-Pro-Pro (lactotripeptides) has been reported. However, circadian rhythm effects determined by ambulatory blood pressure monitoring (ABPM) to eliminate the confounding influence of the white-coat effect have not been fully studied. Twelve hypertensive patients not receiving antihypertensive medication (2 men, 10 women; mean age±standard deviation, 63.5±8.3 years) who had been visiting our clinic for more than 1 year participated in this study. Mean (±standard deviation) systolic blood pressure (SBP) and diastolic blood pressure (DBP) were 142.4±2.6 and 83.5±6.4 mm Hg, respectively, at the first office visit. After patients ingested a fermented milk product containing antihypertensive peptides (2.53 mg Val-Pro-Pro; 1.52 mg Ile-Pro-Pro) for more than 4 weeks, both office SBP and DBP were significantly reduced to a mean (±standard deviation) of 133.3±7.0 mm Hg and 76.5±8.4 mm Hg (P<.001 and P<.005 by paired t-test), respectively. The 24-hour SBP and DBP determined by ABPM were reduced from 127.3±2.4 and 78.7±2.3 mm Hg to 120.2±2.4 and 75.0±2.2 mm Hg (P<.001 and P<.05), respectively. Awake-time SBP (08:00–21:00), night-time SBP (0:00–05:00), and early-morning SBP (06:00–07:00) were reduced from 130.9±2.4 to 123.3±2.3 mm Hg, 118.7±2.9 to 113.2±3.4 mm Hg, and 132.8±4.3 to 122.4±3.9 mm Hg (by paired t-test: P<.001, P<.05, and P<.05), respectively. As seen with DBP measured by ABPM, 24-hour DBP and awake-time DBP were significantly reduced from 78.7±2.3 to 75.0±2.2 mm Hg and 82.1±2.5 to 77.3±2.2 mm Hg (P<.05 and P<.01), respectively. Office BP and 24-hour blood pressure did not significantly differ between the dipper and nondipper groups at baseline. However, after treatment, night-time and early-morning blood pressure were significantly reduced from baseline in the nondipper group (−8.5±2.5 and −15.6±3.7 mm Hg; P<.05 and P<.01, respectively) but not in the dipper group (−2.5±3.6 and −1.2±4.7 mm Hg; P not significant), and the reduction in early-morning blood pressure significantly differed between the groups (P<.05). These results suggest that Val-Pro-Pro and Ile-Pro-Pro decrease blood pressure in patients with stage I hypertension and result not only in lower blood pressure at night-time but also in lower early-morning SBP in nondipper patients.