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Han YH, Peng JB, Gu YC, Quan NB, Yang DY, Li XD. [Analysis of factors influencing lung function in patients with pneumoconiosis]. Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi 2023; 41:663-667. [PMID: 37805425 DOI: 10.3760/cma.j.cn121094-20220509-00244] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 10/09/2023]
Abstract
Objective: To analyze the influencing factors of lung function in pneumoconiosis patients, and to provide reference for clinical treatment. Methods: From July 2020 to December 2020, a questionnaire survey was conducted on pneumoconiosis patients in the jurisdiction by using the "Guangdong Province Occupational Disease Prevention and Control Institute" questionnaire, and the relevant items of patients were examined. The rate of counting data is expressed, and the measurement data is expressed by mean and standard deviation. Chi-square test was used for comparison between groups, trend chi-square test was used for trend analysis of ordered classified data. Multivariate analysis was carried out with binary logistic regression model. Results: A total of 1409 pneumoconiosis patients were enrolled. The abnormal rate of lung function in pneumoconiosis patients was 68.77%. The results of trend Chi-square test showed that the abnormal rate of lung function increased with the age of exposure to dust in different age groups (Chi Sqnare Trend=64.12、8.49、24.20, P<0.05) . In univariate analysis, there were statistical significance in different dust exposure age, working age, pneumoconiosis stage, complications and occupational pneumoconiosis diseases (P<0.05) . Multiple logistic regression results showed that age of exposure to dust, years of service, stage of pneumoconiosis and complications were the main influencing factors of lung function in pneumoconiosis patients (P<0.05) . Compared with patients aged 0-30 years, patients aged 50-70 years and older had a higher rate of abnormal lung function (OR=2.16, 95%CI: 1.12~4.16; OR=4.82, 95%CI: 2.05~11.35, all P<0.05) ; Compared with patients with 0~20 years of service, patients with 20~30 years of service and more than 30 years of service had a higher rate of abnormal lung function (OR=1.58, 95%CI: 1.10~2.25; OR=1.63, 95%CI: 1.28~2.40, P<0.05) ; Compared with stage Ⅰ patients, Stage Ⅱ and Stage Ⅲ patients had a higher rate of abnormal lung function (OR=1.62, 95%CI: 1.20~2.17; OR=2.23, 95%CI: 1.40~3.55, all P<0.05) ; Compared with patients without comorbidities, patients with comorbidities had a higher rate of abnormal lung function (OR=1.68, 95%CI: 1.20~2.38, P<0.05) . Conclusion: The factors such as age of exposure to dust, working age, stage of pneumoconiosis and complications may be the influencing factors of lung function in pneumoconiosis patients.
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Affiliation(s)
- Y H Han
- Guangdong Provincial Institute of Occupational Disease Prevention and Control, Guangdong Occupational Health Engineering Technology Research Center, Guangdong Provincial Key Laboratory of Occupational Disease Prevention and Control, Guangzhou 510300, China School of Public Health, Sun Yat-sen University, Guangzhou 510080, China
| | - J B Peng
- Guangdong Provincial Institute of Occupational Disease Prevention and Control, Guangdong Occupational Health Engineering Technology Research Center, Guangdong Provincial Key Laboratory of Occupational Disease Prevention and Control, Guangzhou 510300, China
| | - Y C Gu
- Guangdong Provincial Institute of Occupational Disease Prevention and Control, Guangdong Occupational Health Engineering Technology Research Center, Guangdong Provincial Key Laboratory of Occupational Disease Prevention and Control, Guangzhou 510300, China
| | - N B Quan
- Guangdong Provincial Institute of Occupational Disease Prevention and Control, Guangdong Occupational Health Engineering Technology Research Center, Guangdong Provincial Key Laboratory of Occupational Disease Prevention and Control, Guangzhou 510300, China
| | - D Y Yang
- Guangdong Provincial Institute of Occupational Disease Prevention and Control, Guangdong Occupational Health Engineering Technology Research Center, Guangdong Provincial Key Laboratory of Occupational Disease Prevention and Control, Guangzhou 510300, China
| | - X D Li
- Guangdong Provincial Institute of Occupational Disease Prevention and Control, Guangdong Occupational Health Engineering Technology Research Center, Guangdong Provincial Key Laboratory of Occupational Disease Prevention and Control, Guangzhou 510300, China
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Han YH, Wan Y, Xiong H, Sun GL. Structural maintenance of chromosomes 2 is identified as an oncogene in bladder cancer in vitro and in vivo. Neoplasma 2020; 67:364-370. [PMID: 31986889 DOI: 10.4149/neo_2020_190510n419] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Accepted: 08/26/2019] [Indexed: 11/08/2022]
Abstract
Taurine upregulated gene 1 (TUG1) has been found to promote bladder cancer cell growth in our recent research. In this study, TUG1-depleted bladder cancer cells were used to identify potent players in bladder cancer. Human gene expression arrays were used for transcriptome profiling of TUG1-depleted bladder cancer cells. Cell proliferation was analyzed by MTT assay. Cell apoptosis and cell cycle were analyzed by flow cytometry. Colony formation assay was used to observe the changes of colony formation rates. Xenograft formation assay was performed in nude mice. Immunohistochemical staining was used to test the gene expression levels in tissues from bladder cancer patients. We found that deregulated genes were strongly enriched in cell cycle or pathways in cancer in TUG1-depleted bladder cancer cells. Structural maintenance of chromosomes 2 (SMC2) was inhibited after TUG1 knockdown. The depletion of TUG1 or SMC2 led to G2/M phase arrest in bladder cancer cells. SMC2 depletion inhibited bladder cancer cell proliferation, promoted apoptosis, decreased colony formation, and reduced tumor growth in xenograft nude mice. Overexpression of SMC2 restored the growth of TUG1-depleted cells. The expression levels of SMC2 were higher in human bladder cancer tissues than that in paired normal tissues. Our data suggest that SMC2 is an oncogene in bladder cancer and depletion of SMC2 might have potential therapeutical significance in bladder cancer.
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Affiliation(s)
- Y H Han
- Department of Clinical Medicine, Tibet University Medical College, Lhasa, China
| | - Y Wan
- Department of Geriatric Medicine and Neurology, West China School of Public Health and West China Forth Hospital, Sichuan University, Chengdu, China
| | - H Xiong
- Department of Clinical Medicine, Tibet University Medical College, Lhasa, China.,Department of Geriatric Medicine and Neurology, West China School of Public Health and West China Forth Hospital, Sichuan University, Chengdu, China
| | - G L Sun
- Department of Clinical Medicine, Tibet University Medical College, Lhasa, China
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Park S, Kwon JH, Han YH, Lee KS. Percutaneous Transcatheter Embolisation of the Renal Artery for Chronic Unilateral Haematuria. Hong Kong J Radiol 2017. [DOI: 10.12809/hkjr1715352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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Ingravallo F, Kim KH, Han YH, Volta A, Chiari P, Taddia P, Kim JS. Difficulties and practices regarding information provision among Korean and Italian nurses. Int Nurs Rev 2017; 64:528-535. [PMID: 28556200 DOI: 10.1111/inr.12374] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
AIM To investigate nurses' opinions and practices of providing information in a global context through cultural comparison. BACKGROUND AND INTRODUCTION Providing sufficient information to patients about nursing interventions and plans is essential for patient-centred care. While many countries have specific legislation making information delivery to patients a legal duty of nurses, no such legislation exists in both the Republic of Korea and Italy; nurses' only guidance is the deontological code. METHODS This was a cross-sectional survey study involving a convenience sample of 174 Korean nurses and 121 Italian nurses working in internal medicine and surgery at university hospitals. Data were collected using a self-administered questionnaire between February and November 2014. The questionnaire assessed demographic and professional characteristics, and difficulties and practices regarding information provision. RESULTS Korean and Italian nurses significantly differed in all demographic and professional characteristics. More Korean than Italian participants reported that their role in providing information was well explained within their teams, but both groups reported the same level and type of difficulties in delivering information. Nurses in both countries regularly informed patients about medications and nursing procedures, but provided information about nursing care plans less frequently. Few nurses frequently provided information to relatives instead of patients. CONCLUSIONS Despite cultural, demographic and professional differences between Korean and Italian nurses, their difficulties and practices in information delivery to patient were similar. IMPLICATIONS FOR NURSING AND HEALTH POLICY Hospital managers and policymakers should be aware that nurse-patient communication can be impaired by organizational factors, patient characteristics or the interaction among providers. Educational interventions and strategies are needed to increase information provision to patients about nursing care plans.
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Affiliation(s)
- F Ingravallo
- Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy
| | - K H Kim
- Red Cross College of Nursing, Chung-Ang University, 84 Heukseok-Ro, Dongjack-Gu, Seoul, 156-756, Republic of Korea
| | - Y H Han
- Department of Nursing, Hallym Polytechnic University, Chuncheon, Republic of Korea
| | - A Volta
- Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy
| | - P Chiari
- Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy
| | - P Taddia
- Nursing, Technical and Rehabilitation Assistance Service, Rizzoli Orthopedic Institute, Bologna, Italy
| | - J S Kim
- Red Cross College of Nursing, Chung-Ang University, 84 Heukseok-Ro, Dongjack-Gu, Seoul, 156-756, Republic of Korea
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Shi SM, Han YH, Wang HB. [Research progress of mutational spectrum and pathophysiology of WFS1 gene in Wolfram syndrome and nonsyndromic low frequency sensorineural hearing loss]. Zhonghua Er Bi Yan Hou Tou Jing Wai Ke Za Zhi 2016; 51:712-715. [PMID: 27666717 DOI: 10.3760/cma.j.issn.1673-0860.2016.09.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Compound homozygous or heterozygous mutations in WFS1 can lead to autosomal recessive Wolfram syndrome (WS), and heterozygous mutations in WFS1 can lead to autosomal dominant non-syndromic low frequency sensorineural hearing loss (LFSNHL). In addition, mutations in the WFS region has relationship with diabetes and psychiatric diseases. In this paper, we provide an overview of genetic research with different phenotypes, including WS and LFSNHL.
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Affiliation(s)
- S M Shi
- Department of Otorhinolaryngology Head and Neck Surgery, Shandong Provincial Hospital Affiliated to Shandong University, Shandong Province Key Laboratory of Otology, Jinan 250021, China
| | - Y H Han
- Department of Otorhinolaryngology Head and Neck Surgery, Shandong Provincial Hospital Affiliated to Shandong University, Shandong Province Key Laboratory of Otology, Jinan 250021, China
| | - H B Wang
- Department of Otorhinolaryngology Head and Neck Surgery, Shandong Provincial Hospital Affiliated to Shandong University, Shandong Province Key Laboratory of Otology, Jinan 250021, China
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Zhang XB, Yin YF, Yao HM, Han YH, Wang N, Ge ZL. [Finite element analysis of different load mode on tooth movement for space closure in patient with bimaxillary protrusion]. Zhonghua Kou Qiang Yi Xue Za Zhi 2016; 51:415-419. [PMID: 27480432 DOI: 10.3760/cma.j.issn.1002-0098.2016.07.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
OBJECTIVE To investigate the stress distribution on the maxillary anterior teeth retracted with sliding mechanics and micro-implant anchorage using different retraction hook heights and positions. METHODS DICOM image data including maxilla and upper teeth were obtained with cone-beam CT. The three-dimensional finite element model was constructed using Mimics software. Brackets and archwire model were constructed using Creo software. The models were instantiated using Pro/Engineer software. Abaqus software was used to simulate the sliding mechanics by loading 2 N force on 0, 2, 4, 6, 8, 10 mm retraction hooks and three different positions, repectively. Rotation of the occlusal plane, the initial displacement and stress distribution of teeth were analyzed. RESULTS Lingual rotation of maxillary central incisor(0.021°), gingival movement of the maxillary first molar(0.005 mm), and clockwise rotation of the maxillary occlusal plane(0.012°) were observed when the force application point located at the archwire level (0 mm). In contrast, 0.235° labial rotation of the maxillary central incisor, 0.015 mm occlusal movement of the maxillary first molar, and 0.075° anti-clockwise rotation of the maxillary occlusal plane were observed when the force application point located at the higher level(10 mm retraction hook). The more the force application point was located posteriorly at the archwire level, the less lingual rotation of the maxillary central incisor and the more buccal displacement of maxillary first molar was observed. CONCLUSIONS Maxillary anterior tooth rotation and retraction, vertical displacement of posterior segment, and rotation of the occlusal plane could be controlled by adjusting the height and position of the retraction hook in space closure using miniscrew and sliding mechanics.
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Affiliation(s)
- X B Zhang
- Department of Orthodontics, School of Stomatology Lanzhou University, Lanzhou 730030, China
| | - Y F Yin
- Department of Orthodontics, School of Stomatology Lanzhou University, Lanzhou 730030, China
| | - H M Yao
- Department of Orthodontics, School of Stomatology Lanzhou University, Lanzhou 730030, China
| | - Y H Han
- Department of Stomatology, Jiuquan City People's Hospital, Jiuquan Gansu 735000, China
| | - N Wang
- Department of Orthodontics, School of Stomatology Lanzhou University, Lanzhou 730030, China
| | - Z L Ge
- Department of Orthodontics, School of Stomatology Lanzhou University, Lanzhou 730030, China
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Ren XY, Zhang LS, Han YH, An T, Liu Y, Li YY, Chen HY. Proteomic research on diapause-related proteins in the female ladybird, Coccinella septempunctata L. Bull Entomol Res 2016; 106:168-174. [PMID: 26603522 DOI: 10.1017/s0007485315000954] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
In the experiments reported here, we used the female ladybird Coccinella septempunctata L. as a model to identify diapause-associated proteins using proteomics technology. Our results indicated that protein expression patterns of diapausing and nondiapausing individuals were highly differentiated. A total of 58 spots showed significant differences in abundance (Ratio > 2 and P < 0.05) according to two-dimensional electrophoresis and GE Image Scanner III analysis. Sixteen protein spots were further investigated using mass spectrometry. Eight proteins were characterized, including chaperones and proteins involved in glucose metabolism, lipid metabolism, and the tricarboxylic acid cycle. Among these proteins, five proteins were upregulated in diapausing female adults, including a chaperone (Symbionin symL), malate dehydrogenase (putative), two proteins linked to lipid metabolism (unknown and conserved hypothetical protein) and phosphoglyceromutase (partial). By contrast, isocitrate dehydrogenase (RH49423p), fumarylacetoacetate hydrolase (AGAP001942-PA), and a putative medium chain acyl-CoA dehydrogenase were downregulated. These results contribute to the understanding of diapause mechanisms of the ladybird C. septempunctata and may suggest methods for improving the application of this natural enemy insect.
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Affiliation(s)
- X Y Ren
- State Key Laboratory for Biology of Plant Diseases and Insect Pests,Institute of Plant Protection,Chinese Academy of Agricultural Sciences;Sino-American Biological Control Laboratory,USDA-ARS,Beijing 100081,P.R. China
| | - L S Zhang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests,Institute of Plant Protection,Chinese Academy of Agricultural Sciences;Sino-American Biological Control Laboratory,USDA-ARS,Beijing 100081,P.R. China
| | - Y H Han
- State Key Laboratory for Biology of Plant Diseases and Insect Pests,Institute of Plant Protection,Chinese Academy of Agricultural Sciences;Sino-American Biological Control Laboratory,USDA-ARS,Beijing 100081,P.R. China
| | - T An
- State Key Laboratory for Biology of Plant Diseases and Insect Pests,Institute of Plant Protection,Chinese Academy of Agricultural Sciences;Sino-American Biological Control Laboratory,USDA-ARS,Beijing 100081,P.R. China
| | - Y Liu
- State Key Laboratory for Biology of Plant Diseases and Insect Pests,Institute of Plant Protection,Chinese Academy of Agricultural Sciences;Sino-American Biological Control Laboratory,USDA-ARS,Beijing 100081,P.R. China
| | - Y Y Li
- State Key Laboratory for Biology of Plant Diseases and Insect Pests,Institute of Plant Protection,Chinese Academy of Agricultural Sciences;Sino-American Biological Control Laboratory,USDA-ARS,Beijing 100081,P.R. China
| | - H Y Chen
- State Key Laboratory for Biology of Plant Diseases and Insect Pests,Institute of Plant Protection,Chinese Academy of Agricultural Sciences;Sino-American Biological Control Laboratory,USDA-ARS,Beijing 100081,P.R. China
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Park KM, Kim TH, Han YH, Mun CW, Shin KJ, Ha SY, Park JS, Kim SE. Brain morphology in juvenile myoclonic epilepsy and absence seizures. Acta Neurol Scand 2016; 133:111-118. [PMID: 25950250 DOI: 10.1111/ane.12436] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/21/2015] [Indexed: 01/12/2023]
Abstract
OBJECTIVE We evaluated the differences in brain morphology among patients with juvenile myoclonic epilepsy according to the occurrence of absence seizures. MATERIALS AND METHODS Twenty-one juvenile myoclonic epilepsy patients with (n = 6) and without (n = 15) absence seizures were enrolled. We analyzed whole-brain T1-weighted magnetic resonance imaging using FreeSurfer 5.1. Measures of cortical morphology, such as thickness, surface area, volume, and curvature, and the volumes of subcortical structures, the cerebellum, and cerebrum, were compared between the groups. Moreover, we quantified correlations between clinical variables and each measures of abnormal brain morphology. RESULTS Compared to normal controls, patients without absence seizures demonstrated thinning of the cortical thickness in the right hemisphere, including the post-central, lingual, orbitofrontal, and lateral occipital cortex. Compared to normal controls, patients with absence seizures had more widespread thinning of the cortical thickness, including the right post-central, lingual, orbitofrontal, and lateral occipital cortexes as well as the right inferior temporal cortex. Additionally, the volume of cerebellar white matter in patients without absence seizures was significantly smaller than that in normal controls. Patients with absence seizures had a much smaller cerebellar white matter volume than normal controls or patients without absence seizures. Moreover, there was significantly positive correlation between the age of seizure onset and the volume of cerebellar white matter in patients with juvenile myoclonic epilepsy. CONCLUSIONS We demonstrated that there were significant brain morphology differences in patients with juvenile myoclonic epilepsy according to the presence of absence seizures. These findings support the hypothesis that juvenile myoclonic epilepsy may be a heterogeneous syndrome.
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Affiliation(s)
- K. M. Park
- Department of Neurology; Haeundae Paik Hospital; Inje University College of Medicine; Busan Korea
| | - T. H. Kim
- Department of Health Science and Technology; Inje University; Gimhae Korea
| | - Y. H. Han
- Centre for Molecular and Cellular Imaging; Samsung Biomedical Research Institute; Seoul Korea
| | - C. W. Mun
- Department of Health Science and Technology; Inje University; Gimhae Korea
- Department of Biomedical Engineering/u-HARC; Inje University; Gimhae Korea
| | - K. J. Shin
- Department of Neurology; Haeundae Paik Hospital; Inje University College of Medicine; Busan Korea
| | - S. Y. Ha
- Department of Neurology; Haeundae Paik Hospital; Inje University College of Medicine; Busan Korea
| | - J. S. Park
- Department of Neurology; Haeundae Paik Hospital; Inje University College of Medicine; Busan Korea
| | - S. E. Kim
- Department of Neurology; Haeundae Paik Hospital; Inje University College of Medicine; Busan Korea
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Abstract
We conducted a case-control study to investigate the influence of IL6 -174G/C (rs1800795) and -572C/G (rs1800796) genetic variants on the development of cerebral thrombosis in a Chinese population. This study included 305 cerebral infarction patients and 326 control subjects enrolled between May 2012 and May 2014. The genotyping of IL6 -174G/C (rs1800795) and -572C/G (rs1800796) polymorphisms was performed using polymerase chain reaction combined with restriction fragment length polymorphism analysis. By using logistic regression, we found that when compared with the wild-type genotype, CC and GC+CC IL6 -174G/C (rs1800795) genotypes were associated with an increased risk of cerebral infarction. Odds ratios (and 95% confidence intervals) were calculated to be 3.10 (1.57-6.41) and 1.63 (1.14-2.33) for the CC and GC+CC genotypes, respectively. In conclusion, our study suggests that the CC genotype and C allele of the IL6 -174G/C (rs1800795) polymorphism are associated with an increased risk of cerebral infarction.
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Affiliation(s)
- Y H Han
- Department of Neurology II, Xinxiang Central Hospital, Xinxiang, Henan, China
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Kim YH, Kim GH, Kim AY, Baek NS, Jeong JI, Han YH, Shin BC, Chung MA, Jung SD. Optimisation of bi-layer resist overhang structure formation and SiO2 sputter-deposition process for fabrication of gold multi-electrode array. RSC Adv 2015. [DOI: 10.1039/c4ra11746h] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
In this paper we report the results on the optimization of the bi-layer lift-off resist (LOR) SiO2 sputter-deposition technique which is ideal for obtaining damage-free multi-electrode array (MEA).
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Affiliation(s)
- Y. H. Kim
- Electronics and Telecommunications Research Institute
- Synapse Device Creative Research Centre
- Daejeon
- South Korea
| | - G. H. Kim
- Electronics and Telecommunications Research Institute
- Synapse Device Creative Research Centre
- Daejeon
- South Korea
| | - A.-Y. Kim
- Electronics and Telecommunications Research Institute
- Synapse Device Creative Research Centre
- Daejeon
- South Korea
| | - N. S. Baek
- Electronics and Telecommunications Research Institute
- Synapse Device Creative Research Centre
- Daejeon
- South Korea
| | - J. I. Jeong
- Electronics and Telecommunications Research Institute
- Synapse Device Creative Research Centre
- Daejeon
- South Korea
| | - Y. H. Han
- Electronics and Telecommunications Research Institute
- Synapse Device Creative Research Centre
- Daejeon
- South Korea
| | - B. C. Shin
- Pusan National University
- Department of Rehabilitation Medicine
- Yangsan
- South Korea
| | - M.-A. Chung
- Electronics and Telecommunications Research Institute
- Synapse Device Creative Research Centre
- Daejeon
- South Korea
| | - S.-D. Jung
- Electronics and Telecommunications Research Institute
- Synapse Device Creative Research Centre
- Daejeon
- South Korea
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Li J, Zhang Y, Xu KC, Yang JY, Han YH, Sun YX, Huang Q. First Report of Wilt of Eucalyptus Caused by Ceratocystis fimbriata in China. Plant Dis 2014; 98:1744. [PMID: 30703923 DOI: 10.1094/pdis-06-14-0580-pdn] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Eucalyptus spp., most of which are native to Australia, are one of the world's most commonly planted forestry crops, and have been widely planted in the tropics and subtropics. Eucalyptus trees are distributed in more than 600 counties in 19 provinces/regions throughout China, especially in the southern regions of the country (1). From April of 2013 to May of 2014, eucalyptus trees were noted to be wilting and dying rapidly in Kunming, Yunnan Province (25°02' N, 102°42' E), southwest China. Symptomatic trees typically have many wilted or dead leaves hanging throughout the tree or on some major branches, sometimes followed by death of the whole tree. Dark brown to black discoloration can be seen in the woody xylem, and elongated cankers were also present on some affected trees. A fungus was consistently isolated from the leaves and cankers when symptomatic tissue was incubated between two slices of fresh carrot root. Spore masses were removed from the apices of perithecia, transferred to malt extract agar medium (MEA), and incubated at 25°C. Perithecia developed on the medium, and were black, globose, 212.5 to 242.4 × 207.5 to 254.2 μm, and possessed a long black neck (952.3 to 1,303.3 μm). Ascospores had the typical "hat" morphology and were 4.3 to 5.2 × 3.0 to 3.8 μm. Cylindrical endoconidia (11.2 to 22.2 × 3.9 to 6.1 μm) were found. Chlamydospores produced on media were ovoid and smooth, and were 7.8 to 9.7 × 9.9 to 12.8 μm. Chains of barrel-shaped conidia were not found. PCR amplification and sequencing of the ITS region of rDNA were carried out for one isolate, E2-2, using the procedures of Thorpe et al. (3). Analysis of ITS sequence data (GenBank Accession No. KJ511481) showed that the isolates were 99% homologous to the isolate of C. fimbriata from diseased Colocasia esculenta in Cuba, China, and Hawaii (AY526304 to 06) by BLAST analysis. Thus, the fungus was identified as C. fimbriata based on morphological and molecular characteristics. Pathogenicity tests were made on 1-year-old E. grandis seedlings as follows. A conidial suspension of each isolate was diluted to 106 conidia/ml, and 0.2 ml was injected into wounds on three petioles on each of five healthy plants of E. grandis, and control seedlings were injected with sterile water that had been placed on MEA plates. The seedlings were incubated at 25°C in moist chambers. After 3 days, all inoculated E. grandis plants showed dark brown to black discoloration in the leaf axils. After 5 days, leaf wilting was present. C. fimbriata was re-isolated from all inoculated symptomatic tissue. No symptoms were visible in the control plants and no fungus was isolated from them. Ceratocystis wilt was first observed in eucalyptus in 1997 in the state of Bahia. This was followed by a report of C. fimbriata causing wilt of E. grandis in the Republic of Congo, Uganda, and Uruguay (2). Chen et al. reported two species of Ceratocystis, C. acaciivora and a previously undescribed species C. chinaeucensis, from eucalyptus plantations in Guangdong Province in China (1). To our knowledge, this is the first report of C. fimbriata causing wilt of eucalyptus in China. References: (1) S. F. Chen et al. Fungal Diversity 58:267, 2011. (2) F. A. Ferreira et al. Fitopatol. Bras. 24:284, 1999. (3) D. J. Thorpe et al. Phytopathology 95:316, 2005.
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Affiliation(s)
- J Li
- College of Plant Protection, Yunnan Agricultural University, Kunming, 650201, Yunnan, China. This work was supported by National Natural Science Foundation of China (No. 31270067)
| | - Y Zhang
- College of Plant Protection, Yunnan Agricultural University, Kunming, 650201, Yunnan, China. This work was supported by National Natural Science Foundation of China (No. 31270067)
| | - K C Xu
- College of Plant Protection, Yunnan Agricultural University, Kunming, 650201, Yunnan, China. This work was supported by National Natural Science Foundation of China (No. 31270067)
| | - J Y Yang
- College of Plant Protection, Yunnan Agricultural University, Kunming, 650201, Yunnan, China. This work was supported by National Natural Science Foundation of China (No. 31270067)
| | - Y H Han
- College of Plant Protection, Yunnan Agricultural University, Kunming, 650201, Yunnan, China. This work was supported by National Natural Science Foundation of China (No. 31270067)
| | - Y X Sun
- College of Plant Protection, Yunnan Agricultural University, Kunming, 650201, Yunnan, China. This work was supported by National Natural Science Foundation of China (No. 31270067)
| | - Q Huang
- College of Plant Protection, Yunnan Agricultural University, Kunming, 650201, Yunnan, China. This work was supported by National Natural Science Foundation of China (No. 31270067)
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Abstract
The loquat (Eriobotrya japonica (Thunb.) Lindl.), an important perennial evergreen fruit crop that originated in China and is also cultivated as an ornamental plant, is well known all over the world for high nutritional, medicinal, economic, and ecological values (4). So far, it has been grown in more than 30 countries (1) and is becoming an important industry in China, Spain, Japan, India, Pakistan, and Turkey (2). During an investigation from May to August of 2013, severely withered loquat plants were observed in Kunming city of Yunnan Province (25°02' N; 102°42' E), Southwest China. Initial symptoms were brown lesions of leaves and canker on one to several branches, leaves of the whole tree turned wilted. Cross sections of diseased plants revealed irregularly shaped brown discoloration in the xylem of the trunk. A fungus was consistently isolated from the leaf when diseased leaves were incubated between two slices of fresh carrot root. Spore masses were picked from the apices of perithecia and transferred to malt extract agar medium (MEA) and incubated at 25°C. After perithecium formation, observed perithecia were black, globose (176.0 to 303.2 × 186.0 to 274.3 μm) and showed a long black neck (634.2 to 809.9 μm). Ascospore had the typical format of a "hat" with dimensions of 4.6 to 6.3 × 3.3 to 4.8 μm. Cylindrical endoconidia (7.1 to 36.1 × 2.9 to 6.0 μm) were found. Chlamydospores were ovoid or obpyriform and smooth (8.6 to 12.1 × 6.9 to 12.1 μm). PCR amplification was carried out for one isolate, YT2. The ITS region of rDNA was sequenced using the procedures of Thorpe et al (3). Analysis of ITS sequence data (GenBank Accession Nos. KF963101 and KF963102) showed that the isolates were 99% homologous to the isolate of Ceratocystis fimbriata from diseased Colocasia esculenta in Cuba, China, and Hawaii (AY526304 to 06) by BLAST analysis. Therefore, the fungus was identified as C. fimbriata based on morphological and molecular characteristics. Pathogenicity of the six isolates from this study was tested by inoculation of 1-year-old pot grown seedlings of loquat. The soil of six plants was inoculated by drenching with 40 ml spore suspension (106 spores/ml). Control plants were inoculated with 40 ml of sterile distilled water. The plants were maintained in a controlled greenhouse at 25°C and watered weekly. After inoculation for 1 week, all plants produced wilt symptoms; as the disease progressed, leaves withered and died after 3 weeks of inoculation while control plants remained symptomless. C. fimbriata was successfully re-isolated from the infected trees and no fungal growth was observed in the controls. The pathogenicity assay showed that C. fimbriata was pathogenic to loquat. To our knowledge, this is the first report of C. fimbriata causing wilt of loquat in China. Since C. fimbriata is one of the most aggressive plant pathogens on a wide variety of perennial as well as agronomic crop plants worldwide, and the infection can pose a significant threat to the production of loquat, it is critical to deploy appropriate management strategies to limit the fungus spread. References: (1) J. J. Feng et al. Acta Hort. 750:117, 2007. (2) J. Janick. Acta Hort. 750:27, 2007. (3) D. J. Thorpe et al. Phytopathology 95:316, 2005. (4) J. Yan et al. Pak. J. Bot. 44:1215, 2012.
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Affiliation(s)
- J Li
- College of Plant Protection, Yunnan Agricultural University, Kunming, 650201, Yunnan, China. This work was supported by National Natural Science Foundation of China (No. 31270067)
| | - J M Gao
- College of Plant Protection, Yunnan Agricultural University, Kunming, 650201, Yunnan, China. This work was supported by National Natural Science Foundation of China (No. 31270067)
| | - Y H Han
- College of Plant Protection, Yunnan Agricultural University, Kunming, 650201, Yunnan, China. This work was supported by National Natural Science Foundation of China (No. 31270067)
| | - Y X Sun
- College of Plant Protection, Yunnan Agricultural University, Kunming, 650201, Yunnan, China. This work was supported by National Natural Science Foundation of China (No. 31270067)
| | - Q Huang
- College of Plant Protection, Yunnan Agricultural University, Kunming, 650201, Yunnan, China. This work was supported by National Natural Science Foundation of China (No. 31270067)
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Han YH, Wang HB, Troyan IA, Gao CX, Eremets MI. Pressure induced ionic-superionic transition in silver iodide at ambient temperature. J Chem Phys 2014; 140:044708. [PMID: 25669568 DOI: 10.1063/1.4862824] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Silver iodide (AgI-V) is an archetypical ionic compound for studying the formation mechanism of a superionic state. Previous studies have proven that superionic AgI with high ionic conductivity greater than 0.1 Ω(-1)cm(-1) could only be obtained at high temperatures. We show in this paper that high pressure could also induce the superionic state in AgI even at ambient temperature. Using electrochemical impedance spectroscopy, we investigated Ag(+) ions diffusing in rock-salt structured AgI-III and KOH-type AgI-V under high pressures and directly observed the superionic state in AgI-V. The diffusion coefficient of AgI-V is ∼3.4 × 10(-4)-8.6 × 10(-4) cm(2)/s in the investigated pressure range of 12-17 GPa, comparable with those of superionic α-AgI and AgI-III'. By analyzing the half infinite length Warburg diffusion process, two parameters α and β, which closely relate to the disordered state of Ag(+) ions, have been determined and it was suggested that Ag(+) ions in AgI-V become disordered. The ionic conductivity of AgI-V is three orders of magnitude higher than that of AgI-III, and has reached around 0.1 Ω(-1)cm(-1). Evidence for all three, the diffusion coefficient, α and β, and conductivity have proven that AgI-V is a superionic conductor at ambient temperature.
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Affiliation(s)
- Y H Han
- Biogeochemistry Department,Max Planck Institute for Chemistry, P.O. Box 3060, 55020 Mainz, Germany
| | - H B Wang
- Biogeochemistry Department,Max Planck Institute for Chemistry, P.O. Box 3060, 55020 Mainz, Germany
| | - I A Troyan
- Biogeochemistry Department,Max Planck Institute for Chemistry, P.O. Box 3060, 55020 Mainz, Germany
| | - C X Gao
- State Key Laboratory of Superhard Materials, Jilin University, 130021 Changchun, China
| | - M I Eremets
- Biogeochemistry Department,Max Planck Institute for Chemistry, P.O. Box 3060, 55020 Mainz, Germany
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Hou WJ, Guan JH, Dong Q, Han YH, Zhang R. Dexamethasone inhibits the effect of paclitaxel on human ovarian carcinoma xenografts in nude mice. Eur Rev Med Pharmacol Sci 2013; 17:2902-2908. [PMID: 24254559] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
BACKGROUND Recent studies showed that dexamethasone (DEX) could render cancer cells resistant to paclitaxel (PTX) induced apoptosis though an unknown mechanism. AIM This study aimed to evaluate the influence of DEX pretreatment on the anti-tumor effect of PTX in an in vivo xenograft model with grafted ovarian cancer SKOV-3 cells innude mice. MATERIALS AND METHODS The xenograft procedure was performed, and the nude mice were grouped into four cohorts of ten that received the following treatments: Control group, DEX group, PTX group and DEX+PTX group. Individual treatments were administered once every three days for a total of 6 courses. The growth of tumors and the inhibition rates were measured. Changes in tissue morphology and cellular ultrastructure were observed using light and transmission electron microscopy. Immunohistochemistry was performed to examine the expression of Ki-67, Bcl-xL and cleaved caspase-3. RESULTS Premedication with DEX reduced the inhibitory effect of PTX on tumor growth by approximately 20% compared to the PTX-only-treated group in the ovarian carcinoma xeno-grafted mice. Hematoxylin-eosin (H&E) staining revealed that significantly fewer cells exhibited vacuolization and apoptosis in the DEX + PTX group compared to the PTX group. Apoptotic characteristics including karyopyknosis, nuclear chromatin condensation along the nuclear membrane and aggregation were observed in both DEX+PTX and PTX groups under electron microscopy. However, these characteristics were less significant in the DEX+PTX group than those in the PTX group. The immunohistochemistry demonstrated that protein expression levels of Ki-67 and Bcl-xL were significantly increased, whereas cleaved caspase-3 decreased in the DEX+PTX group, compared to PTX group (p < 0.0125). CONCLUSIONS DEX inhibits the therapeutic efficacy of PTX in a human ovarian carcinoma SKOV-3 xenograft model.
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Affiliation(s)
- W J Hou
- Department of Obstetrics and Gynecology, Shanghai Jiaotong University-Affiliated Sixth People's Hospital of Fengxian Branch, Shanghai, China.
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Li YX, Wang XG, Yang CH, Cong LL, Wu FF, Xue JG, Han YH. Identification of a locus characteristic of male individuals of buffalo grass [Buchloe dactyloides (Nutt.) Engelm.] by using an RAPD marker. Genet Mol Res 2013; 12:4070-7. [PMID: 24089096 DOI: 10.4238/2013.september.27.8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Buffalo grass [Buchloe dactyloides (Nutt.) Engelm.] plants can be either male, female, or hermaphrodite (monoecious). As there is no morphological difference in the early vegetative growth of these three classes of plants, it is worthwhile to use molecular biological methods to attempt to identify the sex of a plant at this early growth period. In this study, we identified 23 plants that had a stable sex for over at least 3 years. Of these, 9 were male plants, 10 were female plants, and 4 were hermaphrodites. Screening of 300 RAPD primers identified a primer, namely S211 (5'-ttccccgcga-3'), which is capable of identifying male plants. The specific fragment was cloned, sequenced, and submitted to the GenBank database (accession No. JN982469). When used to identify the sex of 188 plants during their first growing season, the S211 primer correctly identified 85.8% of all male plants. Our results showed that the S211 primer can identify the male, and in doing so, it facilitates buffalo grass breeding work.
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Affiliation(s)
- Y X Li
- Department of Grassland Science, China Agricultural University, Beijing, China
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Lee HB, Kim SH, Kang SW, Han YH. Characterisation of mechanically alloyed Ti–Al–B nanocomposite consolidated by spark plasma sintering. ACTA ACUST UNITED AC 2013. [DOI: 10.1179/096797803225009319] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
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17
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Ye YW, Jiang ZM, Li WH, Li ZS, Han YH, Sun L, Wang Y, Xie J, Liu YC, Zhao J, Tang AF, Li XX, Guan ZC, Gui YT, Cai ZM. Down-regulation of TCF21 is associated with poor survival in clear cell renal cell carcinoma. Neoplasma 2013; 59:599-605. [PMID: 22862160 DOI: 10.4149/neo_2012_076] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Transcription factor 21 (TCF21) has been identified as a candidate tumor suppressor at 6q23-q24 that is epigenetically inactivated in many types of human cancers. We recently found that TCF21 methylation level was significantly increased in clear cell renal cell carcinoma (ccRCC). The purpose of this study was to investigate the prognostic impact of TCF21 expression in ccRCC and analyze the relationship between TCF21 expression and methylation level. We used real-time PCR and immunohistochemical staining to detect the expression of TCF21, and used methylation specific-PCR (MS-PCR) to determine the methylation status of TCF21 in ccRCC samples and cell line 786-O. The results showed that TCF21 expression level in ccRCC samples was significantly lower than in normal adjacent tissue samples (NAT samples). The Kaplan-Meier survival analysis demonstrated that TCF21 was a significant prognosticator of cancer-specific survival (p=0.001). Furthermore, the DNA demethylating agent 5'-azacytidine restored part of TCF21 expression by suppressing TCF21 methylation in 786-O. The methylation level of TCF21 in ccRCC samples was much higher than in NAT samples. These results suggest that the expression of TCF21 was an independent prognostic factor for poor survival in patients with ccRCC. Aberrant methylation was an important reason for the down-regulation the expression of TCF21, and may be associated with tumorigenesis in ccRCC.
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Affiliation(s)
- Y W Ye
- guangdong and Shenzhen Key Laboratory of Male Reproductive Medicine and Genetics, Institute of Urology, Peking University Shenzhen Hospital, Shenzhen PKU-HKUST Medical Center, Shenzhen, China
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Hwang YJ, Sohn MJ, Lee BH, Kim SY, Seo JW, Han YH, Lee JY, Cha SJ, Kim YH. Radiosurgery for metastatic spinal tumors: follow-up MR findings. AJNR Am J Neuroradiol 2011; 33:382-7. [PMID: 22033723 DOI: 10.3174/ajnr.a2760] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE MR imaging is the primary tool for evaluation and monitoring of spinal tumors. We retrospectively analyzed the MR imaging findings before and after SRS for metastatic spinal tumors. MATERIALS AND METHODS We reviewed MR imaging findings on 79 metastatic spinal tumor lesions in 44 patients (29 male and 15 female)who had undergone radiosurgery between November 2003 and April 2008. Posttreatment MR imaging was evaluated retrospectively for 3 aspects: 1) changes in tumor volume; 2) changes in T2 signal intensity;and 3) changes in contrast enhancement patterns. RESULTS With regard to tumor volume on MR images, 32 lesions(40.5%) decreased in volume (group 1), 39 (49.4%) showed no change (group 2), and 8 (10.1%) increased in volume (group 3). T2 signal intensities were unchanged in 4 lesions (type 1), homogeneously increased in 3 (type 2), and changed to a homogeneously dark signal in 4 (type 4). The T2 signal intensity was increased and inter mixed with dark signal intensity (type 3) in 68 lesions. A decrease in contrast enhancement with or without non-enhancing foci was seen in 73 lesions. A persistent homogeneous enhancement pattern was seen in all 4 of the type 1 lesions, in 1 of the 3 type 2 lesions, and in 1 of the 68 type 3 lesions. CONCLUSIONS Main MR imaging features of locally controlled metastatic spinal tumors included no increase in tumor volume, increased T2 signal intensity with intermixed T2 dark signal intensity,and decreased contrast enhancement. Follow-up MR imaging also provided several patterns of tumor recurrence [corrected].
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Affiliation(s)
- Y J Hwang
- Department of Radiology, Inje University Ilsan Paik Hospital, College of Medicine, Goyang-si, Gyenggi-do, Republic of Korea.
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Han YH, Zhang ZH, Liu JH, Lu JY, Huang SW, Jin WW. Distribution of the tandem repeat sequences and karyotyping in cucumber ( Cucumis sativus L.) by fluorescence in situ hybridization. Cytogenet Genome Res 2008; 122:80-8. [PMID: 18931490 DOI: 10.1159/000151320] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/12/2008] [Indexed: 11/19/2022] Open
Affiliation(s)
- Y H Han
- National Maize Improvement Center of China, Key Laboratory of Crop Genetic Improvement and Genome Ministry of Agriculture, China Agricultural University, Beijing, China
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Han YH, Kim MY, Kim SY, Kim YH, Hwang YJ, Seo JW, Cha SJ, Hur G. Percutaneous insertion of Zilver stent in malignant biliary obstruction. ACTA ACUST UNITED AC 2006; 31:433-8. [PMID: 16465567 DOI: 10.1007/s00261-005-8017-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2005] [Accepted: 08/23/2005] [Indexed: 11/27/2022]
Abstract
BACKGROUND We evaluated the clinical efficacy and technical feasibility of the percutaneously inserted self-expandable nitinol stent (Zilver stent) for palliation of malignant biliary obstruction. METHODS Seventeen patients with malignant tumors involving the intra- or extrahepatic bile duct who presented with obstructive jaundice underwent percutaneous insertion of a self-expandable nitinol stent. We retrospectively reviewed the hospital records of patients and evaluated the technical feasibility on stent placement, complications, patient survival, and duration of stent patency. RESULTS Percutaneous biliary stenting with 27 Zilver stents was performed in 17 patients with malignant biliary obstruction. Technical success was 95%. Malposition of the stent was encountered in one patient. Minor technical problems were encountered in two patients: the introducer tip was broken during stent insertion, so endoscopic removal was done. Mean follow-up period for the 17 patients was 182 days (range 29-485 days): nine patients died of progressive disease at a mean follow-up of 151 days (range 61-371days) after stent insertion and eight patients remained alive at the final follow-up of 216 days (range 29-485 days). The median survival period for all patients was 277 days. The stent occlusion rate was 26% and the mean patency period was 280 days. In five patients, seven stents were obstructed by tumor ingrowth and overgrowth. Stent patency rates were 100%, 100%, 75%, 61%, and 41% at 1, 2, 3, 6, and 12 months, respectively. A late complication, erosive bleeding of the hepatic artery by the stent, developed in one patient. CONCLUSION Percutaneous biliary stenting using the nitinol stent is technically feasible and safe and clinically efficacious treatment for malignant biliary obstruction, even with a minor technical problem during stent insertion.
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Affiliation(s)
- Y H Han
- Department of Radiology, Ilsan Paik Hospital, Medical College of Inje University, 2240, Daewha-dong, Ilsan-gu, Goyang-si, Gyonggi-do, 411-706, Korea.
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Abstract
Stormwater runoff from highway land use is a common non-point source of pollutants. A large quantity of highway stormwater runoff characteristics were collected in California during the past three years. Correlations among various water quality parameters and constituents were performed using data sets collected over the 2000-2001, 2001-2002, and 2002-2003 wet seasons for 18, 21 and 23 storm events at three highway sites in west Los Angeles, California. In addition, statistical and graphical correlation analysis of the mass first flush ratio (MFF) with storm characteristics was made to determine if the first flush is related to site or storm characteristics. The results and analyses performed indicate that (1) TSS correlates well with most particulate-bound metals. However, TSS was poorly correlated with most other pollutants. (2) Strong correlations were also observed among dissolved and total metals; DOC, COD, TKN and oil and grease; conductivity and Cl. (3) Total metals, COD and DOC were generally well correlated with mass first flush, suggesting that BMPs that treat the early portion of runoff have an opportunity to remove high concentrations of these pollutants.
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Affiliation(s)
- Y H Han
- Civil and Environmental Engineering Department, University of California, Los Angeles, CA 90095-1593, USA.
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Abstract
BACKGROUND Late-onset Tay-Sachs disease (LOTS) is an adult-onset, autosomal recessive, progressive variant of GM2 gangliosidosis, characterized by involvement of the cerebellum and anterior horn cells. OBJECTIVE To determine the range of visual and ocular motor abnormalities in LOTS, as a prelude to evaluating the effectiveness of novel therapies. METHODS Fourteen patients with biochemically confirmed LOTS (8 men; age range 24 to 53 years; disease duration 5 to 30 years) and 10 age-matched control subjects were studied. Snellen visual acuity, contrast sensitivity, color vision, stereopsis, and visual fields were measured, and optic fundi were photographed. Horizontal and vertical eye movements (search coil) were recorded, and saccades, pursuit, vestibulo-ocular reflex (VOR), vergence, and optokinetic (OK) responses were measured. RESULTS All patients showed normal visual functions and optic fundi. The main eye movement abnormality concerned saccades, which were "multistep," consisting of a series of small saccades and larger movements that showed transient decelerations. Larger saccades ended earlier and more abruptly (greater peak deceleration) in LOTS patients than in control subjects; these changes can be attributed to premature termination of the saccadic pulse. Smooth-pursuit and slow-phase OK gains were reduced, but VOR, vergence, and gaze holding were normal. CONCLUSIONS Patients with late-onset Tay-Sachs disease (LOTS) show characteristic abnormalities of saccades but normal afferent visual systems. Hypometria, transient decelerations, and premature termination of saccades suggest disruption of a "latch circuit" that normally inhibits pontine omnipause neurons, permitting burst neurons to discharge until the eye movement is completed. These measurable abnormalities of saccades provide a means to evaluate the effects of novel treatments for LOTS.
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Affiliation(s)
- J C Rucker
- Department of Neurology, Veterans Affairs Medical Center and University Hospitals, Case Western Reserve University, Cleveland, OH 44106-5040, USA
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Han YH, Lou HX, Ren DM, Sun LR, Ma B, Ji M. Stereoselective metabolism of silybin diastereoisomers in the glucuronidation process. J Pharm Biomed Anal 2004; 34:1071-8. [PMID: 15019041 DOI: 10.1016/j.jpba.2003.12.002] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2003] [Revised: 11/22/2003] [Accepted: 12/01/2003] [Indexed: 11/18/2022]
Abstract
A separation method for the hepatoprotective drug silybin and its metabolites by RP-HPLC was described. Based on this separation, the stereoselectivity of the metabolism of silybin was investigated by incubation of the drug and its two diastereoisomers with bovine liver microsomes. Information about the structures of these metabolites was obtained, using UV, HPLC/MS and NMR spectra. Four major metabolites (M(1), M(4) of silybin A and M(2), M(5) of silybin B), were prepared by preparative HPLC, and their configurations were accomplished by NMR spectra. A HPLC method was used to quantify the metabolites. The results showed that silybin was extensively metabolized and the major sites for glucuronidation were the C-20, C-7, at phenolic OH groups. Furthermore, the results obtained reveal that there was significant stereoselectivity in the glucuronidation process of silybin. Silybin B was glucuronidated at a more efficient rate than its diastereoisomer, and glucuronidation of silybin B was much preferred at the 20 position, while that of silybin A was similar at both 7 and 20 position.
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Affiliation(s)
- Y H Han
- School of Pharmaceutical Sciences, Shandong University, Jinan 250012, China
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Han YH, Yon M, Hyun TH. Folate intake estimated with an updated database and its association to blood folate and homocysteine in Korean college students. Eur J Clin Nutr 2004; 59:246-54. [PMID: 15483632 DOI: 10.1038/sj.ejcn.1602065] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
OBJECTIVE To measure folate content in cooked foods commonly consumed in Korea for evaluating its relation to folate nutriture of college students. DESIGN Folate content in 32 raw and cooked foods was measured by microbiological assay after trienzyme extraction. These values and the previously published values of 110 raw foods commonly consumed in Korea were used to update the currently available food tables to estimate dietary folate intake of 106 students based on a 3-day 24-h recall. The association of folate intake with blood folate and homocysteine concentrations was evaluated. SETTING Cheongju, Korea. SUBJECTS Healthy college students aged 18 to 27 y old (44 males and 62 females). RESULTS The average folate loss in 32 foods caused by cooking was 29%. The mean daily dietary folate intakes estimated with an updated database were 406 and 305 mug in males and females, respectively. About 10% of both male and female students showed low serum folate (<6.8 nmol/l). Folate intake was positively correlated with serum and erythrocyte folate concentrations in female students (r=0.27 and 0.29, respectively, P<0.05), and negatively correlated with serum homocysteine in male students (r=-0.41, P<0.05). CONCLUSIONS Mean dietary folate intake was higher than those of previous studies since the database was updated using values obtained with trienzyme extraction. Folate intake for the general population should be re-evaluated using reliable food folate values obtained with trienzyme extraction.
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Affiliation(s)
- Y H Han
- Department of Food and Nutrition, Chungbuk National University, Gaeshin-dong, Cheongju, Korea
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Kellinghaus C, Iwasaki M, Leigh JR, Alexopoulos A, Hornig K, Kumar AN, Han YH, Luders HO. Effects of Blinks and Eyelid Closure on the EEG. KLIN NEUROPHYSIOL 2004. [DOI: 10.1055/s-2004-832042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Han YH, Ichikawa K, Utsumi H. A kinetic study of enhancing effect by phenolic compounds on the hydroxyl radical generation during ozonation. Water Sci Technol 2004; 50:97-102. [PMID: 15566192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Ozone decomposition in aqueous solution proceeds through a radical type chain mechanism. These reactions involve the very reactive and catalytic intermediates O2- radical, OH radical, HO2 radical, OH-, H2O2, etc. OH radical is proposed as an important factor in the ozonation of water among them. In the present study, the enhancing effects of several phenolic compounds; phenol, 2-, 3-, 4-monochloro, 2,4-dichloro, 2,4,6-trichlorophenol on OH radical generation were mathematically evaluated using the electron spin resonance (ESR)/spin-trapping technique. OH radical was trapped with a 5,5-dimethyl-1-pyrroline-N-oxide (DMPO) as a stable adduct, DMPO-OH. The initial velocities of DMPO-OH generation in ozonated water containing phenolic compounds were quantitatively measured using a combined system of ESR spectroscopy with stopped-flow apparatus, which was controlled by homemade software. The initial velocities of DMPO-OH generation increased as a function of the ozone concentration. The relation among ozone concentration, amount of phenolic compounds and the initial velocity (v0) of DMPO-OH generation was mathematically analyzed and the following equation was obtained, v0 (10(-6) M/s) = (A' x [PhOHs (10(-9) M)] + 0.0005) exp (60 x [ozone (10(-9) M)]). The equation fitted very well with the experimental results, and the correlation coefficient was larger than 0.98.
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Affiliation(s)
- Y H Han
- Department of Bio-function Science, Faculty of Pharmaceutical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi, Fukuoka, Japan.
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Yang JZ, Si TM, Ruan Y, Ling YS, Han YH, Wang XL, Zhou M, Zhang HY, Kong QM, Liu C, Zhang DR, Yu YQ, Liu SZ, Ju GZ, Shu L, Ma DL, Zhang D. Association study of neuregulin 1 gene with schizophrenia. Mol Psychiatry 2003; 8:706-9. [PMID: 12874607 DOI: 10.1038/sj.mp.4001377] [Citation(s) in RCA: 188] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
A number of studies have indicated that 8p22-p12 is likely to harbor schizophrenia susceptibility loci. In this region, the candidate gene of interest, neuregulin 1 (NRG1), may play a role in the pathogenesis of schizophrenia. Then in the present study, we performed the linkage disequilibrium to determine the association between three genetic variants (SNPs: rs3924999, rs2954041, SNP8NRG221533) on NRG1 gene and schizophrenia in 246 Chinese Han schizophrenic family trios using PCR-based restriction fragment length polymorphism method and denaturing high-performance liquid chromatography. The transmission disequilibrium test analysis for each variant showed a significant difference between two transmitted alleles even after Bonferroni correction (rs3924999, P=0.007752; rs2954041, P=0.0009309; SNP8NRG221533, P=0.012606). The global chi(2) test for haplotype transmission also revealed a strong association (chi(2)=46.068, df=7, P&<0.000001). Our results suggest that the NRG1 gene may play a role in conferring susceptibility to the disease.
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Affiliation(s)
- J Z Yang
- Institute of Mental Health, Peking University, Beijing 100083, China
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Abstract
The physical locations of the 5S and 45S rDNA sequences were examined in three types of teosinte, Zea mays ssp. mexicana (2n = 20), Zea diploperennis (2n = 20) and Zea perennis (2n = 40) by biotinylated fluorescence in situ hybridization (FISH). The tested materials only showed one hybridization site of 5S rDNA on their genomes, but they were different in the position of the signals. The hybridization site of Zea mays ssp. mexicana was located on the long arm of chromosome 2, indicating that it is the same as the cultivated maize in the position of 5S rDNA, while the sites of Zea diploperennis and Zea perennis were on the short arms of other chromosomes. For 45S rDNA, one hybridization site was detected at secondary constriction region of the satellite chromosomes in Zea mays ssp. mexicana and Zea diploperennis, while in Zea perennis, besides the site located at the secondary constriction region, a second site on the short arm of another chromosome pair was observed. Our results provide additional evidence for Zea mays ssp. mexicana being a subspecies of Zea mays.
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Affiliation(s)
- Y H Han
- The Key Laboratory of MOE for Plant Developmental Biology, Wuhan University, Wuhan Hubei, P.R. China
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Kojima T, Matsushima E, Ohta K, Toru M, Han YH, Shen YC, Moussaoui D, David I, Sato K, Yamashita I, Kathmann N, Hippius H, Thavundayil JX, Lal S, Vasavan Nair NP, Potkin SG, Prilipko L. Stability of exploratory eye movements as a marker of schizophrenia--a WHO multi-center study. World Health Organization. Schizophr Res 2001; 52:203-13. [PMID: 11705714 DOI: 10.1016/s0920-9964(00)00181-x] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The exploratory eye movements of patients with schizophrenia reportedly differ from those of patients without schizophrenia and healthy controls. In an attempt to determine whether exploratory eye movements provide valid markers for schizophrenia, the present collaborative study was conducted in six countries to analyze the stability of and variation in the following parameters of exploratory eye movements: the number of eye fixations (NEFs) and mean eye scanning length (MESL) in a retention task; the cognitive search score (CSS) that indicates how frequently the eye focused on each important area of a figure in order to recognize it in a comparison task; and the responsive search score (RSS), which reflects the frequency of eye fixations on each section of a figure in response to questioning in a comparison task. In addition, we investigated the validity of the currently employed discriminant function to extract a common feature of schizophrenia by applying it to the findings of the present study. The exploratory eye movements of 145 patients with schizophrenia, 116 depressed patients and 124 healthy controls at seven WHO collaborative centers in six countries were measured using eye mark recorders during viewing of stationary S-shaped figures in two sequential tasks. The RSSs of patients with schizophrenia were found to be significantly lower than those of depressed patients or healthy controls irrespective of geographical location, with no significant difference existing between the RSSs for depressed patients and those for healthy controls. By inserting the RSS and NEF data for each subject into the formula used to calculate discriminant function, patients with schizophrenia could be discriminated from depressed patients and healthy controls with a sensitivity of 89.0% and a specificity of 86.7%. The RSS is an exploratory eye movement parameter that detected schizophrenia irrespective of culture, race and various other subject variables. Furthermore, it is indicative of the stable, significant difference that exists between subjects with and without schizophrenia. The results of discriminant analysis confirm the previously reported validity of discriminant function.
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Affiliation(s)
- T Kojima
- Department of Neuropsychiatry, Nihon University School of Medicine, Oyaguchi Kamimachi 30-1, Itabashi-ku, Tokyo 173-8610, Japan
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30
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Abstract
The four species of microalgae (Dunaliella bardawil, Chlorella minutissima, Pavlova lutheri and Haematococcus pluvialis) were immobilized in Ca-alginate capsules as a basic study for the development of the economic cultivation process. Under the batch culture of aerobic conditions, the thickness of the capsule membrane and CO2 supply did not affect the growth of the immobilized microalgae, Dunaliella bardawil. Cell concentration of immobilized microalgae in the capsule was higher than those of immobilized microalgae in beads and free cells. The cell concentrations of microencapsulated Dunaliella bardawil and Haematococcus pluvialis were five times greater than that of free cells. Based on these results, microencapsulation for the culture of microalgae was an effective method for the high-density cultivation. In comparison to the immobilized cultivation on the bioreactor type, it was more effective for the cultivation in the bubble column bioreactor than that in the stirrer tank bioreactor.
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Affiliation(s)
- D S Joo
- East Coastal Marine Bioresources Research Center, Kangnung National University, Korea
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Park KB, Do YS, Kang WK, Choo SW, Han YH, Suh SW, Lee SJ, Park KS, Choo IW. Malignant obstruction of gastric outlet and duodenum: palliation with flexible covered metallic stents. Radiology 2001; 219:679-83. [PMID: 11376254 DOI: 10.1148/radiology.219.3.r01jn21679] [Citation(s) in RCA: 120] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
PURPOSE To assess the usefulness of flexible covered metallic stents in the palliation of malignant obstruction of the gastric outlet and duodenum. MATERIALS AND METHODS Twenty-four consecutive patients with malignant obstruction of the gastric outlet (n = 22) or duodenum (n = 2) underwent palliative treatment with self-expandable flexible covered metallic stents. Fourteen patients had advanced gastric carcinoma at the antrum and/or pylorus, and eight had obstruction at the anastomosis site of previous gastrojejunostomy. Complications and clinical status were investigated during the study period. RESULTS The technical success rate was 75% (18 of 24 patients). Twenty-one stents were placed in 18 patients by using an introducer 6 (n = 7) or 8 mm (n = 14) in diameter. The mean follow-up period was 3.4 months (range, 1 week to 9 months). Symptoms improved in 12 (67%) patients after the procedure. There was no change in symptoms in five and a decrease in one. Twelve patients died during the follow-up period (mean survival, 4.3 months). The complication rate was 25% (six of 24 patients), including stent migration (n = 5) and fracture (n = 3). CONCLUSION Flexible covered metallic stent placement can be useful for palliation in patients with malignant obstruction of the gastric outlet or duodenum.
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Affiliation(s)
- K B Park
- Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50, Ilwon-Dong, Kangnam-Ku, Seoul, 135-710, Korea
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Han YH, Kato Y, Haramura M, Ohta M, Matsuoka H, Sugiyama Y. Physicochemical parameters responsible for the affinity of methotrexate analogs for rat canalicular multispecific organic anion transporter (cMOAT/MRP2). Pharm Res 2001; 18:579-86. [PMID: 11465411 DOI: 10.1023/a:1011064806507] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
PURPOSE Canalicular multispecific organic anion transporter (cMOAT/MRP2) is known to exhibit a broad substrate specificity toward amphiphatic organic anions, including methotrexate (MTX). The present study aims to identify the physicochemical properties of MTX derivatives that correlate with recognition specificity by cMOAT/MRP2. METHODS We examined the inhibitory effect of MTX and 24 analogs on the transport of [3H]-S-(2,4-dinitrophenyl)glutathione by cMOAT/MRP2. The affinity constants of these compounds were compared with their physicochemical parameters. The primary active transport of several compounds was also confirmed. RESULTS The affinity constants closely correlated with the octanol/water partition coefficient (clogP), and a linear combination of polar and nonpolar surface areas. The affinity for cMOAT/MRP2 also closely correlated with the molecular weight, which also showed a significant correlation with nonpolar surface area and clogP. CONCLUSIONS Recognition by cMOAT/MRP2 depends on a balance of dynamic surface properties between the polar and nonpolar regions of MTX analogs. The so-called "molecular weight threshold" for the cMOAT/MRP2 affinity of these compounds can be explained by their physicochemical parameters, especially their nonpolar surface areas.
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Affiliation(s)
- Y H Han
- Graduate School of Pharmaceutical Sciences, University of Tokyo, Japan
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Do YS, Choo SW, Suh SW, Kang WK, Rhee PL, Kim K, Shim YM, Park KB, Han YH, Choo IW. Malignant esophagogastric junction obstruction: palliative treatment with an antireflux valve stent. J Vasc Interv Radiol 2001; 12:647-51. [PMID: 11340148 DOI: 10.1016/s1051-0443(07)61493-6] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
The authors assessed the efficacy of an antireflux valve stent in the palliation of malignant esophagogastric junction (EGJ) obstruction after in vitro testing of the stent. Seventeen patients with inoperable malignant EGJ obstruction were treated. Antireflux valves, made of three polyurethane leaflets, were attached to the distal part of the stent to prevent reflux. When the flow rate of normal saline was 100 mL/sec in the forward direction, the valve fully opened at a pressure of 10 mm Hg. When the flow rate of normal saline was 0.35 mL/sec in the backward direction, the valve nearly completely closed at a pressure of 10 mm Hg. Stent placement was successful in all patients without complications. The median dysphagia score decreased significantly, from 3.0 (dysphagia to liquids) to 1.0 (dysphagia to normal solid food) (P < .0005). No patients experienced reflux symptoms. There was one case of stent migration. A valve stent that can prevent major reflux is an effective device for the palliation of malignant EGJ obstruction.
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Affiliation(s)
- Y S Do
- Department of Radiology, Sungkyunkwan University School of Medicine, Samsung Medical Center, 50 Ilwon-dong, Kangnam-ku, Seoul 135-710, Korea
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Kim KM, Giedt CD, Basañez G, O'Neill JW, Hill JJ, Han YH, Tzung SP, Zimmerberg J, Hockenbery DM, Zhang KY. Biophysical characterization of recombinant human Bcl-2 and its interactions with an inhibitory ligand, antimycin A. Biochemistry 2001; 40:4911-22. [PMID: 11305906 DOI: 10.1021/bi002368e] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Apoptosis is an essential physiological process, regulated by the family of Bcl-2-related proteins. However, the molecular mechanism by which Bcl-2 regulates apoptosis still remains elusive. Here we report the functional studies of recombinant human Bcl-2 with the deletion of 22 residues at the C-terminal membrane-anchoring region (rhBcl-2Delta22). Characterization of rhBcl-2Delta22 showed that the recombinant protein is homogeneous and monodisperse in nondenaturing solutions, stable at room temperature in the presence of a metal chelator, and an alpha-helical protein with unfolding of secondary structure at a T(m) of 62.8 degrees C. Optimal membrane pore formation by rhBcl-2Delta22 required negatively charged phospholipids. The existence of a hydrophobic groove in rhBcl-2Delta22 was demonstrated by the fluorescence enhancement of the hydrophobic ANS probe with which a pro-apoptotic Bak BH3 peptide competed. The respiratory inhibitor antimycin A also bound to the hydrophobic groove of rhBcl-2Delta22 with a K(d) of 0.82 microM. The optimal binding conformation of antimycin A was predicted from molecular docking of antimycin A with the hBcl-2 model created by homology modeling. Antimycin A selectively induces apoptosis in cells overexpressing Bcl-2, suggesting that hydrophobic groove-binding compounds may act as selective apoptotic triggers in tumor cells.
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Affiliation(s)
- K M Kim
- Divisions of Basic Sciences and Clinical Research, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109, USA
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Han YH, Chung YH, Kim TY, Hong SJ, Choi JD, Chung YJ. Crystallization of Clonorchis sinensis 26 kDa glutathione S-transferase and its fusion proteins with peptides of different lengths. Acta Crystallogr D Biol Crystallogr 2001; 57:579-81. [PMID: 11264588 DOI: 10.1107/s0907444900019314] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2000] [Accepted: 11/30/2000] [Indexed: 11/10/2022]
Abstract
A Clonorchis sinensis 26 kDa glutathione S-transferase (CsGST) and its fusion proteins containing 14 and 48 amino-acid peptides at the N-terminus have been crystallized using polyethylene glycol monomethylether 550 as a precipitant. Crystals of the three proteins show very similar crystal properties: they diffract to at least 2.3 A resolution and belong to the orthorhombic space group P2(1)2(1)2(1). The unit-cell parameters of CsGST crystals were a = 66.64 (1), b = 68.91 (1), c = 123.41 (2) A, which are very close to those of the crystals of the two fusion proteins. In addition, CsGST fusion proteins containing varying extents of N-terminal-extended peptides are incorporated into a crystal, indicating that the extended peptides have little effect on crystal packing. These results suggest that the crystallization system of CsGST/peptide fusion protein may be generally applicable to obtain crystals of small peptides.
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Affiliation(s)
- Y H Han
- School of Biological Sciences, Chungbuk National University, Cheongju 360-763, South Korea
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Han YH, Kato Y, Watanabe Y, Terao K, Asoh Y, Sugiyama Y. Carrier-mediated hepatobiliary transport of a novel antifolate, N-[4-[(2,4-dianninopteridine-6-yl)methyl]-3,4-dihydro-2H-1,4-benzothiazin-7-yl]carbonyl-L-homoglutamic acid, in rats. Drug Metab Dispos 2001; 29:394-400. [PMID: 11259322] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023] Open
Abstract
The hepatic uptake and biliary excretion of a novel methotrexate derivative, N-[4-[(2,4-diamminopteridine-6-yl)methyl]-3,4-dihydro-2H-1,4-benzothiazin-7-yl]carbonyl-L-homoglutamic acid (MX-68), were examined in rats in vitro using isolated hepatocytes and bile canalicular membrane vesicles (CMVs), respectively. The uptake of MX-68 by isolated rat hepatocytes showed a saturable component (Km = 2.15 microM and Vmax = 2.34 pmol/min/mg of protein) and was inhibited by ATP-depletors and anionic compounds such as taurocholate and probenecid. [3H]MX-68 uptake was also inhibited by folate analogs such as methotrexate and 5CH3-tetrahydrofolate, but the effect of these compounds was slightly less than that of unlabeled MX-68. On replacing Na+ with choline, MX-68 uptake remained unchanged, whereas the methotrexate uptake was reduced. Uptake of MX-68 increased as the extracellular pH fell from 7.5 to 5.5. These results suggest that MX-68 is taken up via active transport systems. The uptake of MX-68 by CMVs prepared from normal rats exhibited clear ATP dependence, whereas ATP had only a minimal effect on the uptake by CMVs from Eisai-hyperbilirubinemic rats with a hereditary deficiency in canalicular multispecific organic anion transporter (cMOAT). The initial uptake rate of ATP-dependent MX-68 transport showed saturation with kinetic parameters similar to those of methotrexate. MX-68 inhibited the ATP-dependent transport of 2,4-dinitrophenyl-S-glutathione, a typical substrate for cMOAT, the inhibition constant (162 microM) being comparable with the Km of ATP-dependent MX-68 transport. These results suggest that the biliary excretion of MX-68 via the bile canalicular membrane is mediated mainly by cMOAT. In conclusion, active transport systems are involved in membrane penetration of MX-68 both at sinusoidal and canalicular sides in the liver, the latter being mainly involved with methotrexate (MTX) whereas the former differs partially from that for MTX.
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Affiliation(s)
- Y H Han
- Graduate School of Pharmaceutical Sciences, University of Tokyo, Bunkyo-ku, Tokyo, Japan
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Han YH, Sweet DH, Hu DN, Pritchard JB. Characterization of a novel cationic drug transporter in human retinal pigment epithelial cells. J Pharmacol Exp Ther 2001; 296:450-7. [PMID: 11160630] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023] Open
Abstract
Retinal pigment epithelial (RPE) cells transport a variety of solutes, but the capacity of human RPE cells to transport drugs and xenobiotics is not well understood. As an initial step to address this issue, we have examined human RPE transport of verapamil. Transport of [3H]verapamil was measured in two human RPE cell lines (RPE/Hu and ARPE-19) grown to confluence on 12-well culture plates. Verapamil uptake by RPE/Hu cells was highly concentrative, reaching cell-to-medium ratios as high as 42 by 1 h. Uptake was saturable, with an apparent K(m) of 7.2 microM. Verapamil uptake decreased in the presence of metabolic inhibitors, low temperature, and organic cations, including quinidine, pyrilamine, quinacrine, and diphenhydramine. However, other organic cations, including tetraethylammonium and cimetidine failed to inhibit. Verapamil uptake was also inhibited by the cationic antiglaucoma drugs diltiazem, timolol, and propranolol. Verapamil uptake was insensitive to changes in membrane potential. However, transport was markedly altered by changes in pH. Decreasing external pH inhibited uptake, whereas efflux was stimulated. Intracellular acidification via NH4Cl prepulse also stimulated uptake. Identical findings were obtained using the commercially available cell line ARPE-19. In view of its unique specificity, the RPE cell verapamil transporter described above is a novel, heretofore undescribed, organic cation transporter, distinct from the known members of the OCT family of organic cation transporters.
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Affiliation(s)
- Y H Han
- Laboratory of Pharmacology and Chemistry, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, North Carolina 27709, USA
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Han YH, Ham JH, Lee NJ, Park CH, Shin YH, Lee DU. Antimutagenic activity of 5alpha-cholest-7-en-3beta-ol, a new component from the starfish asterina pectinifera. Biol Pharm Bull 2000; 23:1247-9. [PMID: 11041261 DOI: 10.1248/bpb.23.1247] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
From the butanol fraction of the starfish Asterina pectinifera Müler et Troschel (Asteriidae), we have isolated a new component, 5alpha-cholest-7-en-3beta-ol. Its antigenotoxic and antimutagenic activities were examined by the SOS chromotest with Escherichia coli PQ37 and by Ames test with Salmonella typhimurium TA1538, respectively. 5alpha-Cholest-7-en-3beta-ol showed potent antigenotoxic activity against the mutagens, both MNNG and NQO. For 100% of antigenotoxicity, the concentration of the compound applied against MNNG and NQO were 10 microg and 5 microg per reaction tube, respectively. Its antimutagenic activity with S. typhimurium TA1538 against the mutagen MNNG was very effective. When its concentrations were varied from 1 up to 10 microg dose per plate, the inhibition ratio of revertant CFU of TA1538 per plate was increased accordingly, from 25.2 to 99.2%. These results suggest that 5alpha-cholest-7-en-3beta-ol possesses antigenotoxic and antimutagenic activity and might be useful as a chemopreventive agent.
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Affiliation(s)
- Y H Han
- Department of Biology, Dongguk University, Kyongju, Kyongbuk, Republic of Korea
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Choo SW, Do YS, Park KB, Kim SH, Han YH, Choo I. Transjugular liver biopsy: modified Ross transseptal needle versus quick-core biopsy needle. Abdom Imaging 2000; 25:483-5. [PMID: 10931981 DOI: 10.1007/s002610000043] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/15/2023]
Abstract
BACKGROUND We evaluated the differences in sample adequacy and safety between a transseptal needle and Quick-core biopsy needle for transjugular liver biopsy. METHODS Eighteen consecutive patients who had a bleeding diatheses and/or ascites underwent transjugular liver biopsy using a transseptal needle (11 patients) and Quick-core biopsy needle (seven patients). The length of the specimens was measured before fixation. A pathologist reviewed histologic slides for sample adequacy and pathologic diagnoses. Clinical records were reviewed for complication. RESULTS In all patients, liver biopsy was successful. A total of 45 specimens were obtained, with an average of 2.5 passes per patient. The length of specimen was significantly longer with the Quick-core biopsy needle than with the transseptal needle (p<0.05). Biopsied tissue was fragmented in 17 of 25 specimens with the transseptal needle but not fragmented in any specimen with the Quick-core biopsy needle. All specimens were determined to be adequate except one with the transseptal needle. There was no early or delayed complication in any patient. CONCLUSION Transjugular liver biopsy is a safe and effective procedure without any significant difference in complication and adequacy when using a transseptal needle or Quick-core biopsy needle. Larger specimens can be obtained without tissue fragmentation with the Quick-core biopsy needle.
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Affiliation(s)
- S W Choo
- Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Ilwon-Dong, Kangnam-Gu, Seoul, 135-710, Korea
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Abstract
Binding and transport properties of methotrexate (MTX) and its novel derivative, MX-68, were examined in brush-border membrane vesicles (BBMVs) isolated from rat kidneys. The uptake of MTX, MX-68 and folic acid by BBMVs was stimulated by an inwardly-directed H(+) gradient. Such H(+)-dependent uptake of folic acid is compatible with a previous report (Bhandari et al., Biochim Biophys Acta 1988; 937: 211). The MTX uptake exhibits saturation with a K(m) of 0.834 microM. Although the uptake of these three compounds at optimal pH depended on the osmolarity of the medium, a substantial portion of the uptake was osmolarity-insensitive. By changing the medium osmolarity, the uptake by BBMVs could be separately discriminated as osmolarity-sensitive and insensitive portions, representing transport into the intravesicular space and binding to the surface of BBMVs, respectively. For all three compounds, the binding increased in a time-dependent manner, while the amount transported reached a maximum after a relatively short incubation period. The transport of folic acid, but not its binding, exhibited an overshoot phenomenon under conditions of an inward H(+) gradient. The present results suggest that reabsorption of MTX and MX-68 in the kidney is governed by both their binding and transport mechanisms, with a similar kinetic profile to that of folic acid. The involvement of a transport system seems to make a relatively small contribution to the reabsorption of MTX assessed in BBMVs compared with MX-68 and folic acid.
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Affiliation(s)
- Y H Han
- Graduate School of Pharmaceutical Sciences, University of Tokyo, Hongo, Bunkyo-ku, Tokyo, Japan
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Han YH, Kato Y, Sugiyama Y. Nonlinear disposition kinetics of a novel antifolate, MX-68, in rats. J Pharmacol Exp Ther 1999; 291:204-12. [PMID: 10490906] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023] Open
Abstract
The excretion and tissue distribution kinetics of a novel antifolate, MX-68, were evaluated under conditions of a continuous steady-state infusion in Sprague-Dawley rats (SDRs). The biliary excretion clearance defined with respect to the hepatic concentration (CL(bile, h)) was much lower in Eisai hyperbilirubinemic rats with a hereditary deficiency in canalicular multispecific organic anion transporter than that in SDRs, suggesting the involvement of canalicular multispecific organic anion transporter in its transport across the bile canalicular membrane. The CL(bile, h) in SDRs increased as the infusion rate increased; this can be largely explained by saturation of the intracellular binding of MX-68. On the other hand, the urinary excretion clearance defined with respect to the renal concentration (CL(urine, k)) was comparable for the two strains but showed an increase and subsequent decrease as the renal concentration increased. This nonlinear profile was also found even when the CL(urine, k) was normalized by the unbound fraction in kidney. Therefore, this kinetic profile represents the saturation of both reabsorption and secretion. Reabsorption of MX-68 in kidney was supported by its saturable transport by renal brush border membrane vesicles at an inward H(+) gradient. The liver-to-plasma unbound concentration ratio decreased as the steady-state plasma concentration increased, suggesting that MX-68 is taken up by a saturable mechanism or mechanisms. Thus, the saturation of transport systems across several plasma membranes and intracellular binding in both the liver and kidney produce the nonlinear disposition of MX-68.
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Affiliation(s)
- Y H Han
- Graduate School of Pharmaceutical Sciences, University of Tokyo, Hongo, Bunkyo-ku, Tokyo, Japan
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Abstract
To explore the oxygen response regulators involved in thiol peroxidase gene (tpx) expression in Escherichia coli, we constructed a single-copy tpx-lacZ operon fusion and monitored tpx-lacZ expression in various genetic backgrounds. Expression of the tpx-lacZ fusion was increased 4-fold by aerobic growth. Anaerobic expression of tpx-lacZ in either (delta)arcA or delta(fnr) strains was 2.5-fold depressed compared with that of the wild-type strain. The results of immunoblotting experiments also demonstrated that ArcA and Fnr regulatory proteins repressed thiol peroxidase gene expression during anaerobic growth. Inspection of the tpx promoter region revealed putative binding sites for ArcA and Fnr. It thus appears that ArcA and Fnr function as repressors by blocking the binding of RNA polymerase to the tpx promoter in E. coli under anaerobic growth conditions.
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Affiliation(s)
- S J Kim
- Department of Genetic Engineering, Pai-Chai University Taejon, Republic of Korea
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Han YH, Chung SJ, Shim CK. Canalicular membrane transport is primarily responsible for the difference in hepatobiliary excretion of triethylmethylammonium and tributylmethylammonium in rats. Drug Metab Dispos 1999; 27:872-9. [PMID: 10421613] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/13/2023] Open
Abstract
Two structurally similar quaternary ammonium compounds, triethylmethylammonium (TEMA, M(r) 116) and tributylmethylammonium (TBuMA, M(r) 200) were used as model compounds to identify the unit process of hepatobiliary excretion that is responsible for markedly different biliary excretion of organic cations (OCs). Cumulative biliary excretion (in percentage of dose; i.v., 12 micromol/kg) was 0.17 for TEMA and 34.5 for TBuMA. In vivo uptake clearance into the liver was 0.686 +/- 0.020 ml/min for TEMA and 0.421 +/- 0.028 ml/min for TBuMA. When the uptake clearance was examined in an isolated hepatocyte system, comparable clearance between TEMA and TBuMA was obtained, consistent with the in vivo result. These observations suggest that uptake into the liver is not the major determinant for the difference in biliary excretion of the OCs. Coadministration of colchicine, an inhibitor of microtubule formation, had no effect on biliary excretion of the model compounds, and the primary site of subcellular distribution of the OCs appears to be the cytosol, suggesting that intracellular movement does not play a major role in the markedly different biliary excretion of the OCs. In contrast, in vivo excretion clearance across the canalicular membrane for TBuMA was 180-fold greater than that for TEMA, and in vitro efflux clearance of TBuMA was smaller than that of TEMA (p <.01), indicative of involvement of these processes in the markedly different biliary excretion of the OCs. Therefore, these data indicate that canalicular transport is primarily responsible for the markedly different biliary excretion of TEMA and TBuMA.
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Affiliation(s)
- Y H Han
- Department of Pharmaceutics, College of Pharmacy, Seoul National University, Seoul, Korea
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Han YH, Kato Y, Kusuhara H, Suzuki H, Shimoda M, Kokue E, Sugiyama Y. Kinetic profile of overall elimination of 5-methyltetrahydropteroylglutamate in rats. Am J Physiol 1999; 276:E580-7. [PMID: 10070027 DOI: 10.1152/ajpendo.1999.276.3.e580] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The in vivo biliary and urinary excretion kinetics of 5-methyltetrahydropteroylglutamate (5-CH3-H4PteGlu) were studied in rats. During infusion at various rates (48-965 nmol. h-1. kg-1), the total body clearance (CLtotal) of 5-CH3-H4PteGlu could be attributed almost entirely to the sum of the biliary and urinary (CLurine,p) excretion clearances. After a 4-h infusion at the highest rate, the 5-CH3-H4PteGlu in the liver was 10 times higher than the endogenous level, whereas its polyglutamate form did not increase, suggesting that most of the infused 5-CH3-H4PteGlu is not incorporated in the polyglutamate pool but is eliminated by excretion. The parallel increase in CLtotal and CLurine,p with the increase in infusion rate might result from saturation of reabsorption at the renal proximal tubules, since the urinary excretion clearance, defined with respect to the kidney concentration, also increased while the biliary excretion clearance, defined with respect to the liver concentration, remained almost constant. We conclude that the hepatobiliary excretion is a relatively low-affinity process with a constant clearance, whereas the renal tubular reabsorption is saturated at higher plasma 5-CH3-H4PteGlu concentration ( approximately 0.5 microM). Urinary excretion becomes the predominant elimination route for any excess 5-CH3-H4PteGlu in the body.
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Affiliation(s)
- Y H Han
- Graduate School of Pharmaceutical Sciences, University of Tokyo, Hongo, Tokyo 113-0033, Japan
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Abstract
By employing 2D-PAGE, a protein differentially expressed during the development of Dictyostelium discoideum was discovered. The full cDNA of this protein was cloned using RT-PCR. The deduced protein is composed of 166 amino acid residues containing four EF-hand domains typical for calcium-binding proteins and was named CBP3. This protein shows little amino acid sequence homology with the other calcium-binding proteins from D. discoideum except EF-hand domains. The CBP3 mRNA was absent in vegetative amebas and accumulated maximally at 6 h of the development on filters. The mRNA level decreased thereafter and disappeared after 12 h of the development, while the protein level peaked at 8 h of development and remained constant thereafter. The mobility of CBP3 on SDS gel was shifted by treatment with EGTA, confirming the Ca2+-binding activity of the protein.
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Affiliation(s)
- Y H Han
- Department of Microbiology, College of Natural Sciences, and Research Center for Molecular Microbiology, Seoul National University, South Korea
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Kusuhara H, Han YH, Shimoda M, Kokue E, Suzuki H, Sugiyama Y. Reduced folate derivatives are endogenous substrates for cMOAT in rats. Am J Physiol 1998; 275:G789-96. [PMID: 9756510 DOI: 10.1152/ajpgi.1998.275.4.g789] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
We examined the role of the canalicular multispecific organic anion transporter (cMOAT) in the biliary excretion of reduced folate derivatives in vivo and in vitro using normal [Sprague-Dawley rats (SDR)] and mutant [Eisai hyperbilirubinemic rats (EHBR)] rats whose cMOAT is hereditarily deficient. In vivo, the biliary excretion of endogenous tetrahydrofolate (H4PteGlu), 5-methyltetrahydrofolate (5-CH3-H4PteGlu), and 5,10-methylenetetrahydrofolate (5, 10-CH2-H4PteGlu) in EHBR was reduced to 8.2%, 1.9%, and 5.5% of those in SDR, respectively, whereas that of 10-formyltetrahydrofolate (10-HCO-H4PteGlu) was detected only in SDR and not in EHBR. Bile drainage caused reduction of endogenous plasma folate concentrations in SDR but not in EHBR. In vitro, significant ATP-dependent uptake of 3H-labeled 5-CH3-H4PteGlu into canalicular membrane vesicles was observed only in SDR. This ATP-dependent uptake was saturable with a Michaelis constant (Km) value of 126 microM, which was comparable with its inhibitor constant (Ki) value of 121 microM for the ATP-dependent uptake of a typical cMOAT substrate, 2,4-dinitrophenyl-S-glutathione (DNP-SG). Vice versa, DNP-SG inhibited the uptake of 5-CH3-H4PteGlu with a Ki of 35 microM, which was similar to its Km value. In addition, H4PteGlu and 5, 10-CH2-H4PteGlu also inhibited the ATP-dependent uptake of DNP-SG. These results indicate that 5-CH3-H4PteGlu and other derivatives are transported via cMOAT. Therefore, reduced folate derivatives are the first endogenous substrates for cMOAT that do not contain glutathione, glucuronide, or sulfate moieties.
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Affiliation(s)
- H Kusuhara
- Graduate School of Pharmaceutical Sciences, University of Tokyo, Bunkyo-ku, Tokyo 113, Japan
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Abstract
The properties of the haem environment of an extracellular peroxidase from Pleurotus ostreatus were studied by electronic absorption spectroscopy. A high-spin ferric form was predominant in the native enzyme and a high-spin ferrous form in the reduced enzyme. Cyanide was readily bound to the haem iron in the native form, thereby changing the enzyme to a low-spin cyano adduct. The electronic absorption spectra of the enzyme were similar to those of lignin peroxidase from Phanerochaete chrysosporium. Compound III of the enzyme was formed after the addition of an excess of H2O2 to the native enzyme, and thereafter spontaneously reverted to the native form. The enzyme oxidized 1-(3,5-dimethoxy-4-hydroxyphenyl)-2-(2-methoxyphenoxy)-1,3-dihydroxyp ropane in the presence of H2O2 to produce 1-(3,5-dimethoxy-4-hydroxyphenyl)-2-(2-methoxyphenoxy)-1-oxo-3-hydroxypr opane , 2,6-dimethoxyhydroquinone, 2-(2-methoxyphenoxy)-3-hydroxypropanal, 2-(2-methoxyphenoxy)-3-hydroxypropanoic acid, 2,6-dimethoxy-1,4-benzoquinone and guaiacol. A similar oxidation pattern was demonstrated with a one-electron oxidant, ammonium cerium(IV)nitrate. Free radicals were detected as intermediates of the enzyme-mediated oxidation of 1-(3,5-dimethoxy-5-hydroxyphenyl)-2-(2-methoxyphenoxy)-1,3-dihydroxyp ropane and acetosyringone. These results can be explained by the mechanisms involving an initial one-electron oxidation of the lignin substructure. This radical may undergo C alpha-C beta cleavage, C alpha-oxidation and alkyl-phenyl cleavage.
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Affiliation(s)
- Y H Han
- Department of Microbiology, College of Natural Sciences, Seoul National University, Republic of Korea
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Youn HD, Kim KJ, Maeng JS, Han YH, Jeong IB, Jeong G, Kang SO, Hah YC. Single electron transfer by an extracellular laccase from the white-rot fungus Pleurotus ostreatus. Microbiology (Reading) 1995; 141 ( Pt 2):393-8. [PMID: 7704270 DOI: 10.1099/13500872-141-2-393] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Two different bands with laccase activity were obtained after nondenaturing PAGE of the culture filtrate of Pleurotus ostreatus. Immunoblot analysis revealed that antisera raised against laccase I were not reactive to laccase II. Laccase I, which exhibited faster mobility on nondenaturing polyacrylamide gel, was purified 42.9-fold with an overall yield of 10.8%. Gel filtration and SDS-PAGE revealed that laccase I is a single polypeptide with a molecular mass of approximately 64 kDa. Laccase I contained 12.5% carbohydrate by weight and 3.9 mol copper (mol protein)-1. The absorption spectrum of laccase I showed a type 1 signal at 605 nm and EPR spectra showed that the parameters of the type 1 and type 2 Cu signals were g parallel = 2.197 and A parallel = 0.009 cm-1, and g parallel = 2.263 and A parallel = 0.0176 cm-1, respectively. The data obtained from the pH profiles suggested that two ionization groups, whose pKa values were 5.60-5.70 and 6.70-6.85, may play an important role in the active site of laccase I as the ligand of copper metal. The optimal pH and temperature for the activity of laccase I were 6.0-6.5 and 30-35 degrees C, respectively. The enzyme had affinity for various lignin-related phenolic compounds: the Km values for ferulic acid and syringic acid were 48 and 89 microM, respectively. EPR spectroscopic study of the action of laccase I on 3,5-dimethoxy-5-hydroxyacetophenone indicated that this enzyme catalyses single electron transfer with the formation of the phenoxy radical as an intermediate.
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Affiliation(s)
- H D Youn
- Department of Microbiology, College of Natural Sciences, Seoul National University, Republic of Korea
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Siegfried JM, Han YH, DeMichele MA, Hunt JD, Gaither AL, Cuttitta F. Production of gastrin-releasing peptide by a non-small cell lung carcinoma cell line adapted to serum-free and growth factor-free conditions. J Biol Chem 1994; 269:8596-603. [PMID: 8132585] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Gastrin-releasing peptide is an important growth-modulating factor in developing lung epithelium. It is known to be produced by small cell carcinomas of the lung, and an autocrine loop involving gastrin-releasing peptide and its receptor has been demonstrated in many small cell lung tumors. We investigated whether such an autocrine loop could also be demonstrated in non-small cell lung carcinoma, since gastrin-releasing peptide is known to stimulate human bronchial epithelial cells, from which non-small cell tumors should emerge. We report here that gastrin-releasing peptide is produced by a bronchiolo-alveolar carcinoma cell line (A549) adapted to serum-free and growth factor-free conditions. A549 cells adapted to these conditions, termed A549-R0 cells, display extensive membrane interdigitations, Golgi apparatus, and secretory-like granules, and grow as a mixture of attached colonies and floating cells. Gastrin-releasing peptide is present in the conditioned medium produced by A549-R0 cells. Colony formation of cells derived from a squamous cell carcinoma of the lung, 239T, was stimulated 9-fold by A549-R0 conditioned medium or by authentic gastrin-releasing peptide, measured in serum-free conditions. The growth stimulatory activity was inhibited by a monoclonal antibody to gastrin-releasing peptide. Transcripts for receptors for the bombesin family of peptides were also demonstrated in A549-R0 cells and 239T cells. These results demonstrate that non-small cell lung carcinomas can secrete gastrin-releasing peptide and can also respond to the peptide.
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Affiliation(s)
- J M Siegfried
- Department of Pharmacology, University of Pittsburgh, Pennsylvania 15261
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Shin KS, Youn HD, Han YH, Kang SO, Hah YC. Purification and characterisation of D-glucose oxidase from white-rot fungus Pleurotus ostreatus. Eur J Biochem 1993; 215:747-52. [PMID: 8354282 DOI: 10.1111/j.1432-1033.1993.tb18088.x] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
D-Glucose oxidase was purified 27.5-fold to apparent homogeneity with an overall yield of 23.8%, from Pleurotus ostreatus, through a purification procedure of ammonium sulphate precipitation, gel-permeation, anion-exchange and hydrophobic-interaction chromatography. The molecular mass determined by gel filtration was found to be 290 kDa. SDS/PAGE revealed that the enzyme consists of four subunits with a molecular mass of 70 kDa. The absorption spectra of the enzyme exhibit maxima at 280, 360 and 460 nm. The enzyme shows a fluorescence spectrum with an excitation maximum at 470 nm and an emission maximum at 530 nm. These results indicate that the prosthetic group of the enzyme is flavin and that the enzyme contains 4 mol flavin/mol enzyme. The enzyme is optimally active at 50 degrees C and at pH 5.5-6.0. It exhibits broad affinity for various sugars and specificity for D-glucose with Km value of 1.34 mM. 2,6-Dichloroindophenol, Wurster's blue, and 4-benzoquinone can function as electron acceptors but phenazine methosulphate cannot function as an electron acceptor. The enzyme is inhibited completely by mercuric chloride and partially by silver sulphate, sodium azide 8-hydroxyquinoline.
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Affiliation(s)
- K S Shin
- Department of Microbiology, College of Sciences, Taejon University, South Korea
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