Study on the γ + X, γ + β, γ + α Coincidence Summing Effects of the Intrinsic Background Instrument Spectrum of a LaBr3(Ce) Scintillation Counter

Sun Shangqing,Ge Liangquan,Li Yuandong,Hu Chuanhao 한국물리학회 2020 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.77 No.12

The energy resolution of a LaBr3(Ce) scintillation counter can reach 2.7% (662 keV) at room temperature. As a radiation measuring device, it has remarkably good characteristics. However, the LaBr3(Ce) crystal has its own intrinsic radioactivity background, which mainly comes from 138La and from 227Ac and its daughters. 138La can emit β, γ and X-rays through β and γ decay; 227Ac and its daughters can emit α, β and γ-rays through α, β and γ decay. α, γ and X-ray energy are characteristic while β-ray energy is continuous. The energy of α, β and X-rays is mainly deposited in the crystal unless the α, β and X-rays at the edge of the crystal can escape from the crystal. Therefore, the α, β, γ and X-rays generated by the intrinsic radioactivity of the crystal are superimposed on the instrument spectrum, which makes the instrument spectrum more complicated and produces the coincidence summing effects of γ + X, γ + β and γ + α. In this research, the GEANT4.9.5 software package was used to simulate the spectra of α, β, γ and X-rays. On the basis of a combination of fitting decomposition and reconstruction, the simulation spectrum of the LaBr3(Ce) self-radioactive background was obtained accurately and was verified by using physical experiments.

AMPK γ is Required for Maintaining Epithelial Cell Structure and Polarity

Hyongjong Koh(고형종) 한국생명과학회 2011 생명과학회지 Vol.21 No.5

AMPK는 catalytic α subunit과 regulatory β 및 γ subunit으로 구성된 인산화 효소로, 그 동안 생체 내 중요 대사 조절자로써 연구되어 왔으나, 최근 유전학 연구를 통해 지금까지 밝혀지지 아니한 새로운 생체기능을 가짐이 밝혀졌다. 본 연구에서 초파리 유전학 기법을 활용하여 AMPK γ subunit 유전자가 결손된 모델 초파리를 제작 하여 연구한 결과, AMPK γ 유전자 결손 시 초파리 embryo의 표피형성이 심각하게 저해됨을 발견하였고, 조직학적 실험을 통해 표피세포의 극성이 AMPK γ 유전자 결손 초파리에서 손상되어 있음을 확인하였다. 또한 세포극성을 조절하는 중요 분자인 MRLC의 인산화 또한 AMPK γ 유전자 결손 시 저해되었으며, AMPK γ 유전자 재도입 시 MRLC인산화와 표피세포의 극성이 모두 회복됨이 확인되어, 초파리 표피세포의 극성유지에 AMPK γ 유전자가 필수적 임을 확인하였다. AMP-activated protein kinase (AMPK), a heterotrimeric complex comprising a catalytic α subunit and regulatory β and γ subunits, has been primarily studied as a major metabolic regulator in various organisms, but recent genetic studies discover its novel physiological functions. The first animal model with no functional AMPK γ subunit gene was generated by using Drosophila genetics. AMPK γ null flies demonstrated lethality with severe defects in cuticle formation. Further histological analysis found that deletion of AMPK γ causes severe defects in cell polarity in embryo epithelia. The phosphorylation of nonmuscle myosin regulatory light chain (MRLC), a critical regulator of epithelial cell polarity, was also diminished in AMPK γ null embryo epithelia. These defects in AMPK γ mutant epithelia were successfully restored by over-expression of AMPK γ. Collectively, these results suggested that AMPK γ is a critical cell polarity regulator in metazoan development.

Helicobacter pylori 감염 위점막에서 Peroxisome Proliferator-activated Receptor (PPAR)γ의 발현

손성현 ( Seong Hyun Son ),김형근 ( Hyung Keun Kim ),지정선 ( Jeong Seon Ji ),조영석 ( Young Seok Cho ),김성수 ( Sung Soo Kim ),채현석 ( Hiun Suk Chae ),최명규 ( Myung Gyu Choi ),한석원 ( Sok Won Han ),최규용 ( Kyu Yong Choi ),정 대한소화기학회 2007 대한소화기학회지 Vol.49 No.2

목적: Peroxisome proliferator-activated receptorγ (PPAR γ)는 핵 전사인자로 염증과 악성종양에 관련된 여러 유전자의 발현을 조절한다. PPAR γ는 대장암뿐만 아니라 위암에서도 발현되며, PPAR γ 배위자는 암세포의 분화와 세포자멸사를 유도한다. H. pylori의 지속적인 감염은 만성위염과 소화성 궤양을 일으키고, 세포 전환율을 변화시킨다. 또한 H. pylori는 위암의 주요한 원인 인자이다. 이에 저자들은 H. pylori 감염이 위점막에서 PPAR γ 발현에 미치는 영향에 대해 알아보고자 하였다. 대상 및 방법: 상부위장관내시경검사를 시행한 39명에서 위점막 검체를 얻었다. H. pylori 감염 여부 확인을 위한 신속요소분해효소검사와 조직 검사를 시행하여 H. pylori 감염 정도와 염증세포들의 침윤 정도를 확인하였다. 면역조직화학염색을 시행하여 위점막 검체에서 PPAR γ 단백의 발현 위치, 발현 정도와 강도를 확인하였다. 또한 PPAR γ의 특이 primer를 이용하여 real time PCR을 시행하여 mRNA의 발현 정도를 확인하였다. 결과: PPAR γ 단백은 선와상피세포의 핵에서 발현되었고, 장상피화생 조직과 위암 조직에서도 발현되었다. PPAR γ 단백 발현은 H. pylori 감염 군에서 3.8±0.4, 비감염군에서 2.6±1.0으로 의미있는 차이를 보였다(p=0.012). PPAR γ mRNA 발현은 대장암군에서 H. pylori 감염군과 비감염군에 비하여 유의하게 증가하였으나(p<0.05), H. pylori 감염군과 비감염군에서는 유의한 차이가 없었다(p>0.05). 결론: H. pylori 감염이 위점막에서 PPAR γ 단백 발현을 증가시킴을 확인하였고, PPAR γ가 H. pylori에 의해 유발되는 일련의 염증반응에 중요한 역할을 하는 것으로 생각한다. 추후 이에 대한 더 많은 연구가 필요하다. Background/Aims: Peroxisome proliferator-activated receptor γ (PPARγ), a nuclear transcription factor, plays a critical role in the regulation of gene expression associated with inflammation and cancer. PPAR γ is expressed in human gastric cancer as well as in colon cancer. Activation of PPAR γ by ligand produces pro-apoptotic effect and ameliorate growing of cancer cells. Helicobacter pylori (H. pylori) is a main etiologic agent for gastric inflammation, and raises cell turnover in gastric epithelium. Longstanding infection with this organism is related with the development of non-cardiac gastric cancer. The aim of this study was to investigate the effect of H. pylori on the expression of PPARγ protein and mRNA in chronic gastritis. Methods: Gastric biopsy samples were taken from H. pylori infected (n=18) and non-infected (n=21) patients during endoscopic examination. PPAR γ expressions were assessed by real time polymerase chain reaction and immunohistochemistry. Results: PPAR γ was localized to the nuclei of the foveolar epithelial cells in both infected and non-infected mucosa. PPAR γ protein expression was higher in H. pylori infected patients than in non-infected patients (3.8±0.4 vs. 2.6±1.0, H. pylori infected and non-infected, respectively; p<0.05). However, PPAR γ mRNA levels were not significantly different between the two groups (24±18 vs. 29±25, H. pylori infected and noninfected, respectively). Conclusions: PPAR γ expression is increased in the gastric mucosa of H. pylori infected chronic gastritis, which suggests a certain role of PPARγ in the mucosal inflammatory reaction to H. pylori infection. (Korean J Gastroenterol 2007;49:72-78)

Study of the 3He(α,γ)7Be and 3H(α,γ)7Li Reactions at Astrophysical Energies

H. Sadeghi,R. Ghasemi 한국물리학회 2014 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.64 No.11

We have studied the important astrophysical 3He(α,γ)7Be and 3H(α,γ)7Li reactions in the framework of a potential model. 3He(α,γ)7Be and 3H(α,γ)7Li processes are key reactions in both bigbang nucleosynthesis and the p-p chain of hydrogen-burning in stars. The stellar 3He(α,γ)7Be and 3H(α,γ)7Li reactions were analyzed at low energies on the basis of a direct radiative capture mechanism. The astrophysical S-factors near zero energy were calculated without using the effective expansion of the S-factor or the asymptotic wave functions. In this paper, 3He(α,γ)7Be and 3H(α,γ)7Li radiative capture reactions at very low energies are taken as a case study. Using the M3Y potential, we have calculated the astrophysical S-factors for the E1 transition. In comparison with other theoretical methods and available experimental data, excellent agreement is achieved for the astrophysical S-factors of these processes.

T 림프구 아형 측정에서 총 T 림프구 측정의 재현성 및 CD3⁺ CD4^- CD8^- 세포군의 특성

성흥섭,권수진,박찬정,지현숙 대한임상병리학회 2002 대한임상병리학회지 Vol.22 No.2

Precipitation Examination of δ, σ, and γ Phases using Modified Cr/Ni Equivalent Ratios during the Multipass Welding of Stainless Steels

Dong-Yih Lin,Chih-Chun Hsieh 대한금속·재료학회 2009 METALS AND MATERIALS International Vol.15 No.3

The purpose of this study is to discuss the precipitation tendencies of δ, σ, and γ phases using a modified Cr/Ni equivalent ratio with 309L filler after welding dissimilar steels (SUS 304L and AISI 1017) while adding various Si contents of 0.25 wt.%, 0.45 wt.%, and 0.65 wt.% and hot rolling in AISI 309LSi stainless steels at 1200 °C for 2 h. The elemental compositions of δ, σ, and γ phases were performed by EDS in as-hotrolled AISI 309LSi as well as dissimilar welded samples, and the Creq/Nieq ratios were calculated by Hammer & Svensson’s equation. In this research, the Creq/Nieq of phase and matrix were presented as [Creq/Nieq]phase and [Creq/Nieq]matrix, respectively. The modified equation ([Creq/Nieq]modified) was equal to [Creq/Nieq]phase /[Creq/Nieq]matrix, and it was used to examine the effect of materials and processes in the δ, σ, and γ phases. The results indicated the Creq/Nieq ratios of the δ, σ, and γ phases were 2.557~1.304, over 3.143, and 1.229, respectively. The purpose of this study is to discuss the precipitation tendencies of δ, σ, and γ phases using a modified Cr/Ni equivalent ratio with 309L filler after welding dissimilar steels (SUS 304L and AISI 1017) while adding various Si contents of 0.25 wt.%, 0.45 wt.%, and 0.65 wt.% and hot rolling in AISI 309LSi stainless steels at 1200 °C for 2 h. The elemental compositions of δ, σ, and γ phases were performed by EDS in as-hotrolled AISI 309LSi as well as dissimilar welded samples, and the Creq/Nieq ratios were calculated by Hammer & Svensson’s equation. In this research, the Creq/Nieq of phase and matrix were presented as [Creq/Nieq]phase and [Creq/Nieq]matrix, respectively. The modified equation ([Creq/Nieq]modified) was equal to [Creq/Nieq]phase /[Creq/Nieq]matrix, and it was used to examine the effect of materials and processes in the δ, σ, and γ phases. The results indicated the Creq/Nieq ratios of the δ, σ, and γ phases were 2.557~1.304, over 3.143, and 1.229, respectively.

Neuropeptide γ의 구조 및 생리활성

구희정,서정길,김은희,허민도,정준기,박장수,강신원,박남규 부산대학교 유전공학연구소 1997 분자생물학 연구보 Vol.13 No.-

생리활성을 지닌 신경펩타이드의 구조와 활성간의 관계를 규명하기 위하여 고상법으로 합성한 세종류의 neuropeptide γ(mammalian-,trout- 그리고 goldfish-neuropeptide γ)를 사용하여 연구하였다. Circular dichroism spectra에 의하면 mammalian-,trout- 와 goldfish-neuropeptide γ는 완충액 조건하에 모두 random한 구조를 나타내었다. 중성 및 산성 지질 존재 하에서, mammalian-과 trout- neuropeptide γ는 여전히 random한 구조를 취하였다. 그러나, goldfish-neuropeptide γ는 중성 및 산성지질하에서 부분적으로 α-helix구조를 나타내었다. 장관 수축활성에 있어서는 carp 장관, guinea-pig 회장 그리고 rat십이지장에 대하여 비교하였다. Carp에 대해서는 goldfish-neuropeptide γ= trout- neuropeptide γ>mammalian-neuropeptide γ순으로 활서이 나타났다. 그러나, guinea-pig 회장과 rat십이지장에 대해서 mammalian-neuropeptide γ는 어류 유래성 neuropeptide g들 보다 높은 수축활성을 나타내었다. 이러한 결과들은 neuropeptide γ들이 종-특이적인 활성을 나타낸다는 것을 제시한다. The relationship between structure and biological activity was studied on the three neuropeptides(mammalian-,trout- and goldfish-neuropeptide γ)that were syntheized by the solid-phase method. Circular dichroism spectra showed that mammalian-,trout- and goldfish-neuropeptide γadopted an undered structure in buffer solution. In the presence od neutral and acidic liposomes, mammalian-and trout- neuropeptide γ also took a random structure. However, goldfish-neuropeptide γ took an α-helical structure in acidic liposomes. The intestinal motility response was investigated with carp interstines, guinea-pig ileums and rat duodenums. In case of carp intestine, contractine activity was as follows:goldfish-neuropeptide γ= trout- neuropeptide γ> mammalian-neuropeptide γ. On the other hand, the contracile activity of mammalian-neuropeptide γ was more potent than trout- and goldfish-neuropeptide γ in the guinea-pig ileums and rat duodenums. these results suggest that neuropeptide γs showed the species-specific activity.

Anti-IgE mAb Suppresses Systemic Anaphylaxis through the Inhibitory IgG Receptor Fc γ RIIb in Mice

Kang, Nam-In,Jin, Zhe-Wu,Lee, Hern-Ku 대한면역학회 2007 Immune Network Vol.7 No.3

Anti-IgE mAb which binds circulating but not receptor-bound IgE has been shown to be effective in treatment for asthma and other allergic diseases. However, the mechanisms by which anti-IgE mAb influences the pathophysiological responses are remained to be illustrated. This study was undertaken to examine the therapeutic efficacy of non-anaphylactogenic anti-mouse IgE mAb using murine models of IgE-induced systemic fatal anaphylaxis. Methods: Active systemic anaphylaxis was induced by either penicillin V(Pen V) or OVA and passive systemic anaphylaxis was induced by either anaphylactogenic anti-mouse IgE or a mixture of anti-chicken gamma globulin (CGG) IgG1 mAb and CGG. The binding of the Fc portion of anti-IgE to CHO-stable cell line expressing mouse Fc γ RIIb was examined using flow cytometry. Fc fragments of anti-IgE mAb were prepared using papain digestion. The expression of phosphatases in lungs were assessed by Western blotting and immunohistochemistry. Results: Anti-IgE mAb prevented IgE- and IgG-induced active and passive systemic fatal reactions. In both types of anaphylaxis, anti-IgE mAb suppressed antigen-specific IgE responses, but not those of IgG. Anti-IgE mAb neither prevented anaphylaxis nor suppressed the IgE response in Fc γ RIIb-deficient mice. The Fc portion of anti-IgE mAb was bound to murine Fc γ RIIb gene-transfected CHO cells and inhibited systemic anaphylaxis. Anti-IgE mAb blocked the anaphylaxis-induced downregulation of Fc γ RIIb-associated phosphatases such as src homology 2 domain-containing inositol 5-phosphatase (SHIP) and phosphatase and tensin homologue deleted on chromosome ten (PTEN). Conclusion: Anti-IgE mAb prevented anaphylaxis by delivering nonspecific inhibitory signals through the inhibitory IgG receptor, Fc γ RIIb, rather than targeting IgE.

Duvelisib (IPI-145), a PI3K-δ,γ inhibitor, attenuates LPS-induced lung injury through the regulation of MHC II-VEGFR2 epithelial expression

( So Ri Kim ) 대한결핵 및 호흡기학회 2019 대한결핵 및 호흡기학회 추계학술대회 초록집 Vol.127 No.-

Purpose: Duvelisib (IPI-145), a novel targeted PI3K-δ,γ dual inhibitor is a medication used to treat hematologic malignancy. Phosphatidylinositol-3-kinase (PI3K)-δ and -γ are highly expressed in leukocytes in contrast to the other class IA PI3Ks p110α and p110β expressed ubiquitously. Theses two isoforms of PI3K plays a role in immune/ inflammatory responses in the white blood cells, although they have some distinct functions. Recent studies have demonstrated that epithelial cells (ECs) may also have primary immune functions; however, the role of PI3K- δ,γ isoforms in epithelial cell-mediated immune responses are still unclear. Methods: In this study, using LPS-induced acute lung injury animal model, we aimed to evaluate the pharmacologic effects of duvelisib on acute lung injury and to investigate the action mechanism of PI3K-δ,γ dual inhibitor focusing on MHC II-VEGFR2 epithelial expression in LPS-induced lung injury. Results: Our results showed that LPS-instilled mice showed typical features of severe lung inflammation; pulmonary neutrophilia with increases in the production of inflammatory cytokines, vascular leakage, VEGF production, and nuclear translocation of nuclear factor-κB (NF-κB) and PI3K-δ and - γ isoform activation. In addition, confocal microscopic analysis revealed that the expression of VEGFR2 and MHC II were substantially increased in LPS-stimulated lung, including the respiratory epithelium. The treatment with duvelisib substantially improved the LPS-induced pulmonary neutrophilic inflammation compared to the mice treated with vehicle only. Interestingly, the increased epithelial expression of MHC II and VEGFR2 was also reduced significantly. Conclusion: These findings suggest that PI3K-δ,γ dual inhibitor can be a promising therapeutic agent for the treatment of acute lung injury, at least in part, through the attenuation of VEGFR2-MHC II epithelial expression.

Fuzzy γ-Compactness on Fuzzy γ-Minimal Spaces

Jung Il Kim,Won Keun Min,Young Ho Yoo 한국지능시스템학회 2009 INTERNATIONAL JOURNAL of FUZZY LOGIC and INTELLIGE Vol.9 No.4

In [8], we introduced the concept of fuzzy γ-minimal structure which is an extension of smooth fuzzy topological spaces and fuzzy topological spaces in Chang's sense. And we also introduced and studied the fuzzy γ-M continuity. In this paper, we introduce the concepts of fuzzy γ-minimal compactness, almost fuzzy γ-minimal compactness and nearly fuzzy γ-minimal compactness on fuzzy γ-minimal spaces and investigate the relationships between fuzzy γ-M continuous mappings and such types of fuzzy γ-minimal compactness.