A spick-and-span approach to the immobilization of horseradish peroxidase on Au nanospheres incorporated with a methionine/graphene biomatrix for the determination of endocrine disruptor bisphenol A

Vilian, A.T. Ezhil,Giribabu, Krishnan,Choe, Sang Rak,Muruganantham, Rethinasabapathy,Lee, Hoomin,Roh, Changhyun,Huh, Yun Suk,Han, Young-Kyu Elsevier Sequoia 2017 Sensors and actuators. B Chemical Vol.251 No.-

<P><B>Abstract</B></P> <P>In the present study, we employ a straightforward, benign strategy to prepare thiol-functionalized reduced graphene oxide (S-RGO) using methionine as the sulphur source and reducing agent. The immobilization of horseradish peroxidase (HRP) over the AuNPs/S-RGO was developed by incorporating AuNPs on the S-RGO surface. The fabricated HRP/AuNPs/S-RGO electrode exhibits a remarkable decrease in the overpotential and a significantly increased oxidation peak current of bisphenol A (BPA) compared with the bare glassy carbon electrode (GCE) and AuNPs/S-RGO electrode. The biosensor shows an excellent amperometric analytical performance with a low detection limit of 2.6×10<SUP>−12</SUP> M and a linear range from 2.0×10<SUP>−11</SUP> to 1.18×10<SUP>−9</SUP> M, with the response time <2s for BPA. From the results, the apparent Michaelis-Menten constant was calculated as 8.14nM. The HRP/AuNPs/S-RGO biosensor exhibited faster response, adequate storage stability, inexpensive, simple fabrication with disposability, satisfactory reproducibility and repeatability, and outstanding selectivity. Finally, the constructed biosensor was utilized successfully for detecting BPA in tomato juice and milk samples with acceptable results.</P> <P><B>Highlights</B></P> <P> <UL> <LI> HRP/AuNPs/S-RGO biocomposite has been prepared to determine bisphenol A. </LI> <LI> The AuNPs/S-RGO is a promising platform for HRP immobilization. </LI> <LI> The biosensor exhibits excellent stability, reproducibility and high selectivity. </LI> <LI> It exhibits LOD of 2.6×10<SUP>−12</SUP> in a wide linear range from 2.0×10<SUP>−11</SUP> to 1.18×10<SUP>−9</SUP> M. </LI> <LI> It detects bisphenol A in real samples such as tomato juice and milk. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

지역사회간호사업의 내용 및 평가에 관한 연구 : 일부 저소득층 지역사회를 중심으로

방매륜,한영란 이화여자대학교 간호과학연구소 1990 Health & Nursing Vol.2 No.-

All people aspire to a life of health from birth to death. Health is both a right and a responsibility. Health as a human right is expressed in the WHO stated purpose of "Health for All by the Year 2000." In Korea an unequal distribution of health services is related to the ever increasing cost of medical care due to the professionalization of health services, the costly training and education of health care professionals and the soaring costs of medical equipment. It is now generally accepted that the health care wanted and needed by the people is first and foremost the activation and expansion of equally accessable primary health care. This study was carried out by the nursing staff of the Community Health Nursing Clinic of the Social Welfare Centre of Ewha Womans Uni versity. The research problems included the identification of principles from theories supportive of community health nursing services and of criteria from these theories useful for the evaluation of the services and as objectives to guide future services : the description of the i development of the services with a selected community group over a three year period : the evaluation of those services using the criteria developed from the theories and the recommendation of guide - lines for the planning and practice of these and similar community health nursing services. The purpose was to develop a community health nursing model for the expansion and activation of primary health care. The population was a group of women living with their families in a crowded poor area in one district in the Mapho area of Seoul. The women had organized as a mothers association to strength - en their autonomy and decision-making power. The study describes the process whereby the nurses and women worked together from 1987 to 1989 and how the women changed to become active and critical participants in decision making about their health and the nursing services. A theoretical framework was developed to support and guide the practice using Rogers Science of Unitary Human Beings, concepts of Primary Health Care from Health for All by the Year 2000, the health challenges, promotion mechanisms and implementation strategies of the Framework for Health Promotion of the Canadian Ministry of Health and Welfare and principles from the Ottawa Charter for Health Promotion. Four criteria for evaluation of the nursing services were developed from the concepts and principles of the theories. They were : 1. that a nursing theory worthy of providing a world view of the complexity of interrelationships between the human and environmental fields involved in community health nursing - the Science of Unitary Human Beings suplemented by concepts from Primary Health Care and Health Promotion-be used to direct services ; 2. that the people of a community participate in full partnership with service agencies in making decisions regarding the planning, provision and evaluation of their health care ; 3. that both the nurses and people be empowered , and 4. that the community health services be strengthened. Evaluation using the criteria demonstrated the effectiveness of the services in achieving the valued objectives of theory-directed care, empowerment and participation with this population, but relative ineffectiveness in achieving change in official public health policies which would strengthen services or promote a more healthy environment. The four criteria were proposed for use in building more concrete objectives for community health nursing services and the process as helpful for developing future services.

Development of Sensitive Analytical Method of Rhodanthpyrone A by a LC-MS/MS and its Application to Bioavailability Study in Rats

Kang, Bitna,Yoon, Jeong A,Song, Im-Sook,Han, Young Taek,Choi, Min-Koo Korean Society for Mass Spectrometry 2019 Mass spectrometry letters Vol.10 No.3

A sensitive analytical method of rhodanthpyrone A in rat plasma was developed using a liquid chromatography-tandem mass spectrometry (LC-MS/MS). Rhodanthpyrone A and rhodanthpyrone B (internal standard) in rat plasma were extracted by a liquid-liquid extraction method with ethyl acetate. This extraction method gave results in high and reproducible extraction recovery in the range of 73.75-79.90% with no interfering peaks around the peak elution time of rhodanthpyrone A and B. The standard calibration curves for rhodanthpyrone A ranged from 0.5 to 2000 ng/mL were linear with $r^2$ > 0.994 and the inter- and intra-day accuracy and precision and the stability were within acceptance criteria. Using this validated analytical method, pharmacokinetics of rhodanthpyrone A following intravenous and oral administration of rhodanthpyrone A at doses of 2 mg/kg and 30 mg/kg, respectively, were investigated. Rhodanthpyrone A in rat plasma showed multi-exponential elimination pattern with high clearance and volume of distribution values. The absolute oral bioavailability of this compound was calculated as 3.7%. Collectively, the newly developed sensitive LC-MS/MS analytical method of rhodanthpyrone A could be successfully applied to investigate the pharmacokinetic properties of this compound and would be useful for the further studies on the efficacy, toxicity, and biopharmaceutics of rhodanthpyrone A.

Electrical properties and deep traps spectra of a-plane GaN films grown on r-plane sapphire

Polyakov, A.Y.,Smirnov, N.B.,Govorkov, A.V.,Markov, A.V.,Sun, Q.,Zhang, Y.,Yerino, C.D.,Ko, T.S.,Lee, I.H.,Han, J. Elsevier 2010 Materials science & engineering. B, Advanced funct Vol.166 No.3

Electrical properties, deep traps spectra and luminescence spectra were studied for two undoped a-plane GaN (a-GaN) films grown on r-plane sapphire using metalorganic chemical vapor deposition and differing by structural perfection. For sample A, the a-GaN film was directly deposited on AlN buffer. A two-step growth scheme was implemented for sample B, including an initial islanding growth stage and a subsequent enhanced lateral growth. Preliminary detailed X-ray analysis showed that the stacking faults density was 8x10<SUP>5</SUP>cm<SUP>-1</SUP> for sample A and 1.7x10<SUP>5</SUP>cm<SUP>-1</SUP> for sample B. Electrical properties of a-GaN films were largely determined by deep traps with a level near E<SUB>c</SUB> -0.6eV, with other prominent traps having the activation energy of 0.25eV. The Fermi level was pinned by the E<SUB>c</SUB> -0.6eV deep traps for sample A, but shifted to the vicinity of the shallower 0.25eV traps for sample B, most likely due to the reduced density of the 0.6eV traps. This decrease of deep traps density is accompanied by a very pronounced improvement in the overall luminescence intensity. A correlation of the observed improvement in deep traps spectra and luminescence efficiency with the improved crystalline quality of the films is discussed.

Studies on Simultaneous Determination of Chlorophyll a and b, Pheophorbide a, and $\beta-Carotene$ in Chlorella and Spirulina Products

이영자,김소희,김진숙,한정아,서해점,임효정,최수영,Lee Young Ja,Kim So Hee,Kim Jin-Sook,Han Jeong A,Seo Hae Jeom,Lim Hyo Jeong,Choi Soo Young The Korean Society of Food Hygiene and Safety 2005 한국식품위생안전성학회지 Vol.20 No.3

역상 컬럼을 이용하여 건강기능식품 중 클로렐라 및 스피루리나제품에 함유되어 있는 엽록소 a, b,페오포르바이드 a 및 $\beta$-카로틴의 HPLC동시분석법을 확립하였으며, 첨가농도 $50\;\mug/ml$에서 엽록소 a, b, 페오포르바이드 a 및 $\beta$-카로틴에 대한 회수율시험결과, 각각 2.8, 6.0, 10.6 및 $10.4\%$의 상대표준편차와 70.3, 71.6, 60.1 및 $90.5\%$의 회수율을 각각 나타냈다. 이때 검출한계는 $0.1\sim1.0\;\mug/ml$, 정량한계는 $0.2\sim2.0\;\mug/ml$이었으며 검량선 상관계수도 0.995 이상의 직선성을 보여주었다. 국내유통 클로렐라 및 스피루리나제품에 대한 엽록소 a, b,페오포르바이드 a및 $\beta$-카로틴의 함유량을 분석한 결과 엽록소 a $121.g\sim543$, 엽록소 b $0.6\sim160.0$, 페오포르바이드 a 및 P-카로틴 $383.6\sim1713.7mg/ml$ 수준으로 나타났다. 엽록소 b의 함유량은 클로렐라제품에서 평균 374.0 mg/100 g 으로 스피루리나제품의 평균 10.5 mg/100 g 보다 30배 이상 함유하고 있는 것으로 확인되었다. 그러나 $\beta$-카로틴의 함유량은 스피루리나제품이 평균 1335.4 mg/100 g 로 클로렐라제품의 평균 495.0 mg/100 g 보다 평균 함유량에서 2.7배 높은 것으로 나타났다. 국내 건강기능식품공전 중 클로렐라 및 스피루리나제품의 엽록소 a b, 및 페오포르바이드 항목의 규격검사를 본 연구의 동시분석법으로 개정함으로써 각 성분 함량의 정량, 분석시간의 단축 및 비용절감 둥 시험방법을 크게 개선할 수 있을 것으로 기대된다. A simple and sensitive analysis method based on reverse phase (RP) HPLC with UV detector was developed for simultaneous determination of chlorophyll a and b, pheophorbide a and $\beta-Carotene$ in Chlorella and Spirulina products. For added concentration $(50\;\mug/ml)$ of chlorophyll a and b, pheophorbide a and $\beta-Carotene$, recoveries of those were 70.3, 71.6, 60.1 and $90.5\%$, respectively, with relative standard deviations of 2.8,6.0, 10.6 and $10.4\%$. Limit of detection and quantification had ranges of $0.1\sim1.0\;\mug/ml$ and $0.2\sim2.0\;\mug/ml$, respectively. Calibration curve was linear with correlation coefficient of 0.995 for chlorophyll a and b, pheophorbide a and $\beta-Carotene$. Results of simultaneous determination in Chlorella and Spirulina products were showed ranges of $121.g\sim543.0\;\mug/ml$ for chlorophyll a,$0.6\sim160.0\;\mug/ml$ for chlorophyll b, $19.2\sim60.3\;\mug/ml$ for pheophorbide a and $383.6\sim1713.7\;\mug/ml$ for $\beta-Carotene$, respectively. Chlorophyll b contents in Chlorella products were detected above 30 times level to those in Spirulina products. $\beta-Carotene$ contents in Spirulina products were detected 2.7 times level to those in Chlorella products.

Diagnostic usefulness of a T cell-based assay for latent tuberculosis infection in kidney transplant candidates before transplantation

Kim, S.-H.,Lee, S.-O.,Park, I.-A.,Park, S.J.,Choi, S.-H.,Kim, Y.S.,Woo, J.H.,Park, S.-K.,Park, J.S.,Kim, S.C.,Han, D.J. Blackwell Publishing Inc 2010 Transplant infectious disease Vol.12 No.2

<P>S.-H. Kim, S.-O. Lee, I.-A. Park, S.J. Park, S.-H. Choi, Y.S. Kim, J.H. Woo, S.-K. Park, J.S. Park, S.C. Kim, D.J. Han. Diagnostic usefulness of a T cell-based assay for latent tuberculosis infection in kidney transplant candidates before transplantation.Transpl Infect Dis 2010: <B>12:</B> 113–119. All rights reserved</P><P>Background</P><P>The presence of latent tuberculosis (TB) infection (LTBI) should be evaluated before kidney transplantation. Although a new T cell-based assay for diagnosing LTBI gave promising results, this assay has not yet been compared with the tuberculin skin test (TST) for diagnosing LTBI in renal transplant candidates before transplantation.</P><P>Patients and methods</P><P>All adult patients admitted to a single institute for renal transplantation over a 1-year period were prospectively enrolled. A clinically predictive risk of LTBI was defined as: (i) recent close contact with a person with pulmonary TB; (ii) abnormal chest radiography; (iii) a history of untreated or inadequately treated TB; or (iv) a new infection (i.e., a recent conversion of TST).</P><P>Results</P><P>Of 209 renal recipients, 47 (22%) had a positive TST≥5 mm, 21 (10%) had a positive TST≥10 mm, 65 (30%) had a positive T-SPOT.<I>TB</I> test, and 25 (12%) had an indeterminate T-SPOT.<I>TB</I> test. The induration size of TST was significantly associated with a high positivity rate on T-SPOT.<I>TB</I> (<I>P</I><0.001). Agreement between T-SPOT.<I>TB</I> test and TST≥10 mm was fair (<I>k</I>=0.24, 95% confidence interval 0.11–0.36). However, neither univariate nor multivariate analysis showed any association between the clinical risk for LTBI and positivity on T-SPOT.<I>TB</I> or TST.</P><P>Conclusion</P><P>T-SPOT.<I>TB</I> test was more frequently positive than TST in renal transplant candidates. However, further longitudinal studies are awaited to determine whether the ability of T-SPOT.<I>TB</I> assay to detect LTBI in renal transplant recipients can better predict the development of TB than can TST after transplantation.</P>

인간 혈장 아포지단백질 A-1 ( apo A-1 ) 에 대한 단일클론 항체 생산 및 단일클론 항체를 사용한 혈중 apo A-1 측정용 효소면역분석법 ( ELISAs ) 의 개발

이동익,남경수,한문희,김태웅,곽주원,윤미청,최성아 한국지질학회 1994 韓國脂質學會誌 Vol.4 No.1

Recently, apolipoprotein(apo) A-I has received considerable clinical attention as a better marker of inverse correlation with the presence of coronary heart disease than the customary lipid marker, high-density lipoprotein(HDL)-cholesterol. Here we report the production of marine monoclonal antibodies(Mabs) designated as MabA 12 and MabA34 against human apo A-I, recognizing the HDL in plasma. From isotyping analyses, it was found that MabA 12 and MabA34 had IgG2b and IgGI isotype, respectively. Both of the Mabs had κ light chains. The binding specificity of two Mabs was analyzed by immunoblotting and enzyme-linked immunosorbent assay(ELISA). MabA12 and MabA34 reacted well with purified apo A-I or HDL in plasma but they didn't react with low-density lipoproteins(LDL), serum albumin or lipoprotein-deficient serum(LPDS). These indicate that the two Mabs are very specific to human apo A-I in HDL. The validity of the Mabs for serum apo A-I assays was examined by two kinds of ELISA, i.e., non-competitive and competitive ELISA. Both assays revealed that MabA12 or MabA34 reacted well with apo A-I in sample in concentration-dependent manners. Standard curves and, antibody titration curves were drawn. In conclusion, two IgG-type monoclonal antibodies specific to human apo A-I in HDL were produced and applicated for ELISAs of serum apo A-I. The two Mabs would be useful not only for research purposes but also for further development of immuno-diagnostic kits for the measurement of serum apo A-I concentrations.

A Study on Enterovirus Genotypes in Busan, Korea from 2017 to 2022

Nam-Ho Kim,Young-A Jung,Hyeon-Jeong Kwon,Han-Nwi You,이승주 대한미생물학회 2023 Journal of Bacteriology and Virology Vol.53 No.2

Human enteroviruses (HEV) are pathogens that cause a wide variety of clinicalillness such as a hand-foot-mouth disease, herpangina, skin rash, encephalitis,aseptic meningitis and even death in young children. This study was aimed toinvestigate the prevalence of HEV infection in young children in Busan, Korea andanalyze the various genotypes of enterovirus. We collected the stool, throat swaband cerebrospinal fluid samples from admitted pediatrics from 2017 to 2022. HEV detection and genotype identification were performed by real-time RT-PCRand RT-PCR and phylogenetic trees were constructed by neighbor-joining methodcompared with reference strains. A total of 1,412 samples were collected and128 cases (9.1%) were detected. Based on partial VP1 sequencing, a total 93enterovirus isolates were resolved into 4 genotypes and 18 serotypes; Humanenterovirus A, B, D (HEV-A, B, D) and Rhinovirus. HEV-A is 30 isolates included 7serotypes, HEV-B is 63 isolates included 10 serotypes, HEV-D is 1 isolates included1 serotypes and Rhinovirus is 5 isolated included 3 serotypes. Prevalent serotypewas coxsakievirus A10 in 2017, coxsakievirus B5 in 2018, Echovirus 30 in 2019. Thetemporal distribution of HEV epidemics in Busan showed a remarkable seasonalpattern, from June to September. The genotypes of circulating enteroviruseswere diverse from year to year and most of the sequences circulated in Busanshowed homology with reference sequences in neighboring countries such asChina. Monitoring and genotyping of these enteroviruses will play a role inpreventing the development of serious diseases caused by enteroviruses andgenotype analysis can be used as a basic data for epidemiological studies.

A new compound, 1H,8H-pyrano[3,4-c]pyran-1,8-dione, suppresses airway epithelial cell inflammatory responses in a murine model of asthma.

Lee, H,Han, A R,Kim, Y,Choi, S H,Ko, E,Lee, N Y,Jeong, J H,Kim, S H,Bae, H Biomedical Research Press 2009 INTERNATIONAL JOURNAL OF IMMUNOPATHOLOGY AND PHARM Vol.22 No.3

<P>Clinical and experimental studies have established eosinophilia as a sign of allergic disorders. Activation of eosinophils in the airways is believed to cause epithelial tissue injury, contraction of airway smooth muscle and increased bronchial responsiveness. As part of the search for new antiasthmatic agents produced by medicinal plants, the effects of 270 standardized medicinal plant extracts on cytokine-activated A549 human lung epithelial cells were evaluated. After several rounds of activity-guided screening, the new natural compound, 1H,8H-Pyrano[3,4-c]pyran-1,8-dione (PPY), was isolated from Vitex rotundifolia L. To elucidate the mechanism by which the anti-asthmatic responses of PPY occurred in vitro, lung epithelial cells (A549 cell) were stimulated with TNF-alpha, IL-4 and IL-1beta to induce the expression of chemokines and adhesion molecules involved in eosinophil chemotaxis. PPY treatments reduced the expression of eotaxin, IL-8, IL-16 and VCAM-1 mRNA significantly. Additionally, PPY reduced eotaxin secretion in a dose-dependent manner and significantly inhibited eosinophil migration toward A549 medium. In addition, PPY treatment suppressed the phosphorylation of p65 and ERK1/2, suggesting that it can inhibit the MAPK/NF-KB pathway. To clarify the anti-inflammatory and antiasthmatic effects of PPY in vivo, we examined the influence of PPY on the development of pulmonary eosinophilic inflammation in a murine model of asthma. To accomplish this, mice were sensitized and challenged with ovalbumin (OVA) and then examined for the following typical asthmatic reactions: an increase in the number of eosinophils in BALF; the presence of Th2 cytokines such as IL-4 and IL-5 in the BALF; the presence of allergen-specific IgE in the serum; and a marked influx of inflammatory cells into the lung. Taken together, our results revealed that PPY exerts profound inhibitory effects on the accumulation of eosinophils into the airways while reducing the levels of IL-4, IL-5, and IL-13 in the BALF. Therefore, these results suggest that PPY may be useful as a new therapeutic drug for the treatment of allergic asthma.</P>

Aβ-Induced Drp1 phosphorylation through Akt activation promotes excessive mitochondrial fission leading to neuronal apoptosis

Kim, D.I.,Lee, K.H.,Gabr, A.A.,Choi, G.E.,Kim, J.S.,Ko, S.H.,Han, H.J. Elsevier Biomedical Press 2016 Biochimica et biophysica acta, Molecular cell rese Vol.1863 No.11

Mitochondrial dysfunction is known as one of causative factors in Alzheimer's disease (AD), inducing neuronal cell death. Mitochondria regulate their functions through changing their morphology. The present work was undertaken to investigate whether Amyloid β (Aβ) affects mitochondrial morphology in neuronal cells to induce apoptosis. Aβ treatment induced not only the fragmentation of mitochondria but also neuronal apoptosis in association with an increase in caspase-9 and -3 activity. Calcium influx induced by Aβ up-regulated the activation of Akt through CaMKII resulting in changes to the phosphorylation level of Drp1 in a time-dependent manner. Translocation of Drp1 from the cytosol to mitochondria was blocked by CB-124005 (an Akt inhibitor). Recruitment of Drp1 to mitochondria led to ROS generation and mitochondrial fission, accompanied by dysfunction of mitochondria such as loss of membrane potential and ATP production. ROS generation and mitochondrial dysfunction by Aβ were attenuated when treated with Mdivi-1, a selective Drp1 inhibitor. Furthermore, the sustained Akt activation induced not only the fragmentation of mitochondria but also the activation of mTOR, eventually suppressing autophagy. Inhibition of autophagic clearance of Aβ led to increased ROS levels and aggravating mitochondrial defects, which were blocked by Rapamycin (an mTOR inhibitor). In conclusion, sustained phosphorylation of Akt by Aβ directly activates Drp1 and inhibits autophagy through the mTOR pathway. Together, these changes elicit abundant mitochondrial fragmentation resulting in ROS-mediated neuronal apoptosis.