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Yang J, Deng L, Jing M, Xu M, Liu X, Li S, Zhang L, Xi H, Yuan L, Zhou J. Added value of spectral computed tomography quantitative parameters for differentiating tuberculosis-associated fibrosing mediastinitis from endobronchial lung cancer: initial results. Clin Radiol 2024:S0009-9260(24)00132-6. [PMID: 38658213 DOI: 10.1016/j.crad.2024.02.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Revised: 02/09/2024] [Accepted: 02/14/2024] [Indexed: 04/26/2024]
Abstract
OBJECTIVE The objective of this study was to explore the added value of spectral computed tomography (CT) parameters to conventional CT features for differentiating tuberculosis-associated fibrosing mediastinitis (TB-associated FM) from endobronchial lung cancer (EBLC). METHODS Chest spectral CT enhancement images from 109 patients with atelectasis were analyzed retrospectively. These patients were divided into two distinct categories: the TB-associated FM group (n = 77) and the EBLC group (n = 32), based on bronchoscopy and/or pathological findings. The selection of spectrum parameters was optimized with the least absolute shrinkage and selection operator regression analysis. The relationship between the spectrum parameters and conventional parameters was explored using Pearson's correlation. Multivariate logistic regression analysis was used to build spectrum model. The spectrum parameters in the spectrum model were replaced with their corresponding conventional parameters to build the conventional model. Diagnostic performances were evaluated using receiver operating characteristic curve analyses. RESULTS There was a moderate correlation between the parameters ㏒(L-AEFNIC) - ㏒(L-AEFC) (r= 0.419; p< 0.0001), ㏒(O-AEF40KeV) - ㏒(O-AEFC) (r= 0.475; p< 0.0001), [L-A-hydroxyapatite {HAP}(I)] - (L-U-CT) (r= 0.604; p< 0.0001), {arterial enhancement fraction (AEF) derived from normalized iodine concentration (NIC) of lymph node (L-AEFNIC), AEF derived from CT40KeV of bronchial obstruction (O-AEF40KeV), arterial-phase Hydroxyapatite (Iodine) concentration of lymph node [L-A-HAP(I)], AEF derived from conventional CT (AEFC), unenhanced CT value (U-CT)}. Spectrum model could improve diagnostic performances compared to conventional model (area under curve: 0.965 vs 0.916, p= 0.038). CONCLUSION There was a moderate correlation between spectrum parameters and conventional parameters. Integrating conventional CT features with spectrum parameters could further improve the ability in differentiating TB-associated FM from EBLC.
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Affiliation(s)
- J Yang
- Department of Radiology, Lanzhou University Second Hospital, Cuiyingmen No.82, Chengguan District, Lanzhou, 730030, China; Second Clinical School, Lanzhou University, Lanzhou, China; Key Laboratory of Medical Imaging of Gansu Province, Lanzhou, China; Gansu International Scientific and Technological Cooperation Base of Medical Imaging Artificial Intelligence, China.
| | - L Deng
- Department of Radiology, Lanzhou University Second Hospital, Cuiyingmen No.82, Chengguan District, Lanzhou, 730030, China; Second Clinical School, Lanzhou University, Lanzhou, China; Key Laboratory of Medical Imaging of Gansu Province, Lanzhou, China; Gansu International Scientific and Technological Cooperation Base of Medical Imaging Artificial Intelligence, China.
| | - M Jing
- Department of Radiology, Lanzhou University Second Hospital, Cuiyingmen No.82, Chengguan District, Lanzhou, 730030, China; Second Clinical School, Lanzhou University, Lanzhou, China; Key Laboratory of Medical Imaging of Gansu Province, Lanzhou, China; Gansu International Scientific and Technological Cooperation Base of Medical Imaging Artificial Intelligence, China.
| | - M Xu
- Department of Radiology, Lanzhou University Second Hospital, Cuiyingmen No.82, Chengguan District, Lanzhou, 730030, China; Second Clinical School, Lanzhou University, Lanzhou, China; Key Laboratory of Medical Imaging of Gansu Province, Lanzhou, China; Gansu International Scientific and Technological Cooperation Base of Medical Imaging Artificial Intelligence, China.
| | - X Liu
- Department of Radiology, Lanzhou University Second Hospital, Cuiyingmen No.82, Chengguan District, Lanzhou, 730030, China; Second Clinical School, Lanzhou University, Lanzhou, China; Key Laboratory of Medical Imaging of Gansu Province, Lanzhou, China; Gansu International Scientific and Technological Cooperation Base of Medical Imaging Artificial Intelligence, China.
| | - S Li
- Department of Radiology, Lanzhou University Second Hospital, Cuiyingmen No.82, Chengguan District, Lanzhou, 730030, China; Second Clinical School, Lanzhou University, Lanzhou, China; Key Laboratory of Medical Imaging of Gansu Province, Lanzhou, China; Gansu International Scientific and Technological Cooperation Base of Medical Imaging Artificial Intelligence, China.
| | - L Zhang
- Zhang Ye People's Hospital Affiliated to Hexi University, Zhangye, 73400, China.
| | - H Xi
- Department of Radiology, Lanzhou University Second Hospital, Cuiyingmen No.82, Chengguan District, Lanzhou, 730030, China; Second Clinical School, Lanzhou University, Lanzhou, China; Key Laboratory of Medical Imaging of Gansu Province, Lanzhou, China; Gansu International Scientific and Technological Cooperation Base of Medical Imaging Artificial Intelligence, China.
| | - L Yuan
- Department of Radiology, Lanzhou University Second Hospital, Cuiyingmen No.82, Chengguan District, Lanzhou, 730030, China; Second Clinical School, Lanzhou University, Lanzhou, China; Key Laboratory of Medical Imaging of Gansu Province, Lanzhou, China; Gansu International Scientific and Technological Cooperation Base of Medical Imaging Artificial Intelligence, China.
| | - J Zhou
- Department of Radiology, Lanzhou University Second Hospital, Cuiyingmen No.82, Chengguan District, Lanzhou, 730030, China; Second Clinical School, Lanzhou University, Lanzhou, China; Key Laboratory of Medical Imaging of Gansu Province, Lanzhou, China; Gansu International Scientific and Technological Cooperation Base of Medical Imaging Artificial Intelligence, China.
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Jing M, Xi H, Zhu H, Zhang B, Deng L, Han T, Zhang Y, Zhou J. Correlation of pericoronary adipose tissue CT attenuation values of plaques and periplaques with plaque characteristics. Clin Radiol 2023:S0009-9260(23)00172-1. [PMID: 37225572 DOI: 10.1016/j.crad.2023.04.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Revised: 04/19/2023] [Accepted: 04/22/2023] [Indexed: 05/26/2023]
Abstract
AIM To investigate the relationship between different plaque characteristics and pericoronary adipose tissue (PCAT) computed tomography (CT) attenuation values for plaques and periplaques. MATERIALS AND METHODS The data from 188 eligible patients with stable coronary heart disease (280 lesions) who underwent coronary CT angiography between March 2021 and November 2021 were collected retrospectively. All PCAT CT attenuation values of plaques and periplaques (the area within 5 and 10 mm proximal and distal to the plaque) were calculated, and multiple linear regression was used to assess their correlation with different plaque characteristics. RESULTS PCAT CT attenuation of plaques and periplaques was higher in non-calcified plaques (-73.38 ± 10.41 HU, -76.77 ± 10.86 HU, 79.33 ± 11.13 HU, -75.67 ± 11.24 HU, -78.63 ± 12.09 HU) and mixed plaques (-76.83 ± 8.11 HU, -79 [-85, -68.5] HU, -78.55 ± 11 HU, -78.76 ± 9.9 HU, -78.79 ± 11.06 HU) than in calcified plaques (-86.96 ± 10 HU, -84 [-92, -76] HU, -84.14 ± 11.08 HU, -84.91 ± 11.41 HU, -84.59 ± 11.69 HU; all p<0.05) and higher in distal segment plaques than in proximal segment plaques (all p<0.05). Plaque PCAT CT attenuation was lower in plaques with minimal stenosis than in plaques with mild or moderate stenosis (p<0.05). The significant determinants of PCAT CT attenuation values of plaques and periplaques were non-calcified plaques, mixed plaques, and plaques located in the distal segment (all p<0.05). CONCLUSIONS PCAT CT attenuation values in both plaques and periplaques were related to plaque type and location.
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Affiliation(s)
- M Jing
- Department of Radiology, Lanzhou University Second Hospital, Lanzhou, China; Second Clinical School, Lanzhou University, Lanzhou, China; Key Laboratory of Medical Imaging of Gansu Province, Lanzhou, China; Gansu International Scientific and Technological Cooperation Base of Medical Imaging Artificial Intelligence, Lanzhou, China
| | - H Xi
- Department of Radiology, Lanzhou University Second Hospital, Lanzhou, China; Second Clinical School, Lanzhou University, Lanzhou, China; Key Laboratory of Medical Imaging of Gansu Province, Lanzhou, China; Gansu International Scientific and Technological Cooperation Base of Medical Imaging Artificial Intelligence, Lanzhou, China
| | - H Zhu
- Department of Radiology, Lanzhou University Second Hospital, Lanzhou, China; Second Clinical School, Lanzhou University, Lanzhou, China; Key Laboratory of Medical Imaging of Gansu Province, Lanzhou, China; Gansu International Scientific and Technological Cooperation Base of Medical Imaging Artificial Intelligence, Lanzhou, China
| | - B Zhang
- Department of Radiology, Lanzhou University Second Hospital, Lanzhou, China; Second Clinical School, Lanzhou University, Lanzhou, China; Key Laboratory of Medical Imaging of Gansu Province, Lanzhou, China; Gansu International Scientific and Technological Cooperation Base of Medical Imaging Artificial Intelligence, Lanzhou, China
| | - L Deng
- Department of Radiology, Lanzhou University Second Hospital, Lanzhou, China; Second Clinical School, Lanzhou University, Lanzhou, China; Key Laboratory of Medical Imaging of Gansu Province, Lanzhou, China; Gansu International Scientific and Technological Cooperation Base of Medical Imaging Artificial Intelligence, Lanzhou, China
| | - T Han
- Department of Radiology, Lanzhou University Second Hospital, Lanzhou, China; Second Clinical School, Lanzhou University, Lanzhou, China; Key Laboratory of Medical Imaging of Gansu Province, Lanzhou, China; Gansu International Scientific and Technological Cooperation Base of Medical Imaging Artificial Intelligence, Lanzhou, China
| | - Y Zhang
- Department of Radiology, Lanzhou University Second Hospital, Lanzhou, China; Second Clinical School, Lanzhou University, Lanzhou, China; Key Laboratory of Medical Imaging of Gansu Province, Lanzhou, China; Gansu International Scientific and Technological Cooperation Base of Medical Imaging Artificial Intelligence, Lanzhou, China
| | - J Zhou
- Department of Radiology, Lanzhou University Second Hospital, Lanzhou, China; Second Clinical School, Lanzhou University, Lanzhou, China; Key Laboratory of Medical Imaging of Gansu Province, Lanzhou, China; Gansu International Scientific and Technological Cooperation Base of Medical Imaging Artificial Intelligence, Lanzhou, China.
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Zhang B, Lu Y, Li L, Gao Y, Liang W, Xi H, Wang X, Zhang K, Chen L. [Establishment and validation of a nomogram for predicting prognosis of gastric neuroendocrine neoplasms based on data from 490 cases in a single center]. Nan Fang Yi Ke Da Xue Xue Bao 2023; 43:183-190. [PMID: 36946036 PMCID: PMC10034550 DOI: 10.12122/j.issn.1673-4254.2023.02.04] [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] [Subscribe] [Scholar Register] [Indexed: 03/23/2023]
Abstract
OBJECTIVE To develop and validate a nomogram for predicting outcomes of patients with gastric neuroendocrine neoplasms (G-NENs). METHODS We retrospectively collected the clinical data from 490 patients with the diagnosis of G-NEN at our medical center from 2000 to 2021. Log-rank test was used to analyze the overall survival (OS) of the patients. The independent risk factors affecting the prognosis of G-NEN were identified by Cox regression analysis to construct the prognostic nomogram, whose performance was evaluated using the C-index, receiver-operating characteristic (ROC) curve, area under the ROC curve (AUC), calibration curve, DCA, and AUDC. RESULTS Among the 490 G-NEN patients (mean age of 58.6±10.92 years, including 346 male and 144 female patients), 130 (26.5%) had NET G1, 54 (11.0%) had NET G2, 206 (42.0%) had NEC, and 100 (20.5%) had MiNEN. None of the patients had NET G3. The numbers of patients in stage Ⅰ-Ⅳ were 222 (45.3%), 75 (15.3%), 130 (26.5%), and 63 (12.9%), respectively. Univariate and multivariate analyses identified age, pathological grade, tumor location, depth of invasion, lymph node metastasis, distant metastasis, and F-NLR as independent risk factors affecting the survival of the patients (P < 0.05). The C-index of the prognostic nomogram was 0.829 (95% CI: 0.800-0.858), and its AUC for predicting 1-, 3- and 5-year OS were 0.883, 0.895 and 0.944, respectively. The calibration curve confirmed a good consistency between the model prediction results and the actual observations. For predicting 1-year, 3-year and 5-year OS, the TNM staging system and the nomogram had AUC of 0.033 vs 0.0218, 0.191 vs 0.148, and 0.248 vs 0.197, respectively, suggesting higher net benefit and better clinical utility of the nomogram. CONCLUSION The prognostic nomogram established in this study has good predictive performance and clinical value to facilitate prognostic evaluation of individual patients with G-NEN.
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Affiliation(s)
- B Zhang
- Department of General Surgery, First Medical Center of Chinese PLA General Hospital, Beijing 100853, China
| | - Y Lu
- Department of General Surgery, First Medical Center of Chinese PLA General Hospital, Beijing 100853, China
| | - L Li
- Department of General Surgery, First Medical Center of Chinese PLA General Hospital, Beijing 100853, China
| | - Y Gao
- Department of General Surgery, First Medical Center of Chinese PLA General Hospital, Beijing 100853, China
| | - W Liang
- Department of General Surgery, First Medical Center of Chinese PLA General Hospital, Beijing 100853, China
| | - H Xi
- Department of General Surgery, First Medical Center of Chinese PLA General Hospital, Beijing 100853, China
| | - X Wang
- Department of General Surgery, First Medical Center of Chinese PLA General Hospital, Beijing 100853, China
| | - K Zhang
- Department of General Surgery, First Medical Center of Chinese PLA General Hospital, Beijing 100853, China
| | - L Chen
- Department of General Surgery, First Medical Center of Chinese PLA General Hospital, Beijing 100853, China
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Hammond E, Liu Y, Xu F, Liu G, Xi H, Xue L, Bai X, Liao H, Xue S, Zhao S, Zhang A, Kemper J, Afnan M, Mol B, Morbeck D. P–138 When is low quality really low? Should we transfer low-grade blastocysts? Hum Reprod 2021. [DOI: 10.1093/humrep/deab130.137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Study question
What is the live birth rate after single, low-grade blastocyst (LGB) transfer?
Summary answer
The live birth rate for LGBs is 28%, ranging between 15–31% for the different inner cell mass (ICM) and trophectoderm (TE) subgroups of LGBs.
What is known already
Live birth rates following LGB transfer are varied and have been reported to be in the range of 5–39%. However, these estimates are inaccurate as studies investigating live birth rates following LGB transfer are inherently limited by sample size (n = 10–440 for LGB transfers) due to LGBs being ranked last for transfer. Further, these studies are heterogenous with varied LGB definitions and design. Collating LGB live birth data from multiple clinics is warranted to obtain sufficient numbers of LGB transfers to establish reliable live birth rates, and to allow for delineation of different LGB subgroups, including blastocyst age and female age.
Study design, size, duration
We performed a multicentre, multinational retrospective cohort study in 9 IVF centres in China and New Zealand from 2012 to 2019. We studied the outcome of 6966 single blastocyst transfer cycles on days 5–7 (fresh and frozen) according to blastocyst grade, including 875 transfers from LGBs (<3bb, this being the threshold typically applied to LGB studies). Blastocysts with expansion stage 1 or 2 (early blastocysts) were excluded.
Participants/materials, setting, methods
The main outcome measured was live birth rate. Blastocysts were grouped according to quality grade: good-grade blastocysts (GGBs; n = 3849, aa, ab and ba), moderate-grade blastocysts (MGBs; n = 2242, bb) and LGBs (n = 875, ac, ca, bc, cb and cc) and live birth rates compared using the Pearson Chi-squared test. A logistic regression analysis explored the relationship between blastocyst grade and live birth after adjustment for the confounders: clinic, female age, expansion stage, and blastocyst age.
Main results and the role of chance
The live birth rates for GGBs, MGBs and LGBs were 45%, 36% and 28% respectively (p < 0.0001). Within the LGB group, the highest live birth rates were for grade c TE (30%) and the lowest were for grade c ICM (19%). The lowest combined grade (cc) maintained a 15% live birth rate (n = 7/48). After accounting for confounding factors, including female age and blastocyst characteristics, the odds of live birth were 2.33 (95% CI = 1.88–2.89) for GGBs compared to LGBs and 1.56 (95% CI = 1.28–1.92) for MGBs compared to LGBs following fresh and frozen blastocyst transfers (p < 0.0001, odds ratios confirmed in exclusively frozen blastocyst transfer cycles). When stratified by individual ICM and TE grade, the odds of live birth according to ICM grade were 1.31 (a versus b; 95% CI = 1.15–1.48), 2.82 (a versus c; 95% CI = 1.91–4.18) and 2.16 (b versus c; 95% CI = 1.48–3.16; all p < 0.0001). The odds of live birth according to TE grade were 1.33 (a versus b; 95% CI = 1.17–1.50, p < 0.0001), 1.85 (a versus c; 95% CI = 1.45–2.34, p < 0.0001) and 1.39 (b versus c; 95% CI = 1.12–1.73, p = 0.0024).
Limitations, reasons for caution
Despite the large multicentre design of the study, analyses of transfers occurring within the smallest subsets of the LGB group were limited by sample size. The study was not randomised and had a retrospective character.
Wider implications of the findings: LGBs maintain satisfactory live birth rates (averaging 28%) in the general IVF population. Even those in the lowest grading tier maintain modest live birth rates (15%; cc). It is recommended that LGBs not be universally discarded, and instead considered for subsequent frozen embryo transfer to maximize cumulative live birth rates.
Trial registration number
Not applicable
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Affiliation(s)
- E Hammond
- Fertility Associates, Embryology, Auckland, New Zealand
| | - Y Liu
- Monash IVF Group- Southport- Australia, Embryology, Queensland, Australia
| | - F Xu
- Tianjin First Central Hospital, Reproductive Medicine Center, Tianjin, China
| | - G Liu
- Tianjin Aiwei Hospital, Reproductive Center, Tianjin, China
| | - H Xi
- The second affiliated hospital of WenZhou Medical University, Department of Obstetrics and Gynecology, Wenzhou, China
| | - L Xue
- People’s Hospital of Guangxi Zhuang Autonomous Region, Reproductive Medical and Genetic Center, Nanning, China
| | - X Bai
- General Hospital of Tianjin Medical University, Department of Obstetrics and Gynecology, Tianjin, China
| | - H Liao
- The second affiliated hospital of South China University, Reproductive Medicine Center, Hengyang, China
| | - S Xue
- Shanghai East Hospital, Department of Assisted Reproduction, Shanghai, China
| | - S Zhao
- Zaozhuang Maternal and Child Health Care, Reproductive Center, Zaozhuang, China
| | - A Zhang
- Reproductive Medical Center of Ruijin Hospital- School of Medicine- Shanghai Jiao Tong University, Reproductive Medical Center, Shanghai, China
| | - J Kemper
- Monash Women’s- Monash Health- Clayton- Australia, Department of obstetrics and gynaecology, Melbourne, Australia
| | - M Afnan
- Qingdao United Family Hospital- Qingdao- China, Obstetrics and Gynecology, Qingdao, China
| | - B Mol
- Monash Women’s- Monash Health- Clayton- Australia, Obstetrics & Gynaecology Monash Health, Melbourne, Australia
| | - D Morbeck
- Fertility Associates, Embryology, Auckland, New Zealand
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Xi H, Li LJ, Sun LY. [Holistic view of surgery based on membrane anatomy for gastrointestinal tumor]. Zhonghua Wei Chang Wai Ke Za Zhi 2021; 24:560-566. [PMID: 34289537 DOI: 10.3760/cma.j.cn.441530-20210413-00161] [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] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The mesentery is a continuous unity and the operation of digestive carcinoma is the process of mesenteric resection. This paper attempts to simplify the formation process of all kinds of fusion fascia in the process of digestive tract embryogenesis, and to illuminate the continuity of fusion fascia with a holistic concept. This is helpful for beginners to reversely dissect the fusion fascia and maintain the correct surgical plane during operation, and to achieve the purpose of complete mesenteric resection.
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Affiliation(s)
- H Xi
- Department of Oncology, The Fourth Affiliated Hospital, Harbin Medical University, Harbin 150000, China
| | - L J Li
- Department of Oncology, The Fourth Affiliated Hospital, Harbin Medical University, Harbin 150000, China
| | - L Y Sun
- Department of Oncology, The Fourth Affiliated Hospital, Harbin Medical University, Harbin 150000, China
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Harn H, Wang S, Lai Y, Van Handel B, Liang Y, Tsai S, Schiessl IM, Sarkar A, Xi H, Hughes M, Kaemmer S, Tang M, Peti-Peterdi J, Pyle A, Woolley T, Evseenko D, Jiang T, Chuong C. 609 Symmetry breaking of tissue mechanics in wound induced hair follicle regeneration. J Invest Dermatol 2021. [DOI: 10.1016/j.jid.2021.02.638] [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: 10/21/2022]
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Su Y, Lv JL, Yu M, Ma ZH, Xi H, Kou CL, He ZC, Shen AL. Long-term decomposed straw return positively affects the soil microbial community. J Appl Microbiol 2019; 128:138-150. [PMID: 31495045 DOI: 10.1111/jam.14435] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2018] [Revised: 07/24/2019] [Accepted: 08/21/2019] [Indexed: 01/12/2023]
Abstract
AIMS In order to understand the response of soil microbial communities to the long-term of decomposed straw return, the modifications of soil microbial community structure and composition induced by more than 10 years of fresh and decomposed straw return was investigated and the key environmental factors were analysed. METHODS AND RESULTS Phospholipid fatty acid analysis and high-through sequencing technique were applied to analyse the structure and composition of the soil microbial communities. Compared with fresh straw, returning decomposed straw increased the relative abundance of bacteria and fungi by 1·9 and 7·7% at a rate of ~3750 kg ha-1 , and increased by 23·1 and 5·7%, at a rate of ~7500 kg ha-1 respectively. The relative abundance of the bacteria related to soil nitrification increased, but the ones related to soil denitrification decreased with decomposed straw return, which led to higher total nitrogen contents in soils. Moreover, returning decomposed straw reduced pathogenic fungal populations (genus of Alternara), which had significantly positive correlation with soil electric conductivity. It indicated that the long-term of decomposed straw return might have lower risk of soil-borne disease mainly for the reasonable soil salinity. CONCLUSIONS Long-term of decomposed straw return could provide suitable nutrient and salinity for healthier development of soil microbial community, both in abundance and structure, compared with fresh straw return. SIGNIFICANCE AND IMPACT OF THE STUDY The results of the study helps to better understand how the microbial community modifications induced by decomposed straw return benefit on soil health. The obtained key factors impacting soil microbial community variations is meaningful in soil health management under conditions of straw return.
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Affiliation(s)
- Y Su
- Institute of Environment, Resource, Soil and Fertilizer, Zhejiang Academy of Agricultural Sciences, Hangzhou, 310021, China
| | - J L Lv
- Institute of Plant Nutrient, Environment and Resource, Henan Academy of Agricultural Sciences, Zhengzhou, 450002, China
| | - M Yu
- Institute of Environment, Resource, Soil and Fertilizer, Zhejiang Academy of Agricultural Sciences, Hangzhou, 310021, China
| | - Z H Ma
- Institute of Plant Nutrient, Environment and Resource, Henan Academy of Agricultural Sciences, Zhengzhou, 450002, China
| | - H Xi
- Institute of Environment, Resource, Soil and Fertilizer, Zhejiang Academy of Agricultural Sciences, Hangzhou, 310021, China
| | - C L Kou
- Institute of Plant Nutrient, Environment and Resource, Henan Academy of Agricultural Sciences, Zhengzhou, 450002, China
| | - Z C He
- Institute of Environment, Resource, Soil and Fertilizer, Zhejiang Academy of Agricultural Sciences, Hangzhou, 310021, China
| | - A L Shen
- Institute of Environment, Resource, Soil and Fertilizer, Zhejiang Academy of Agricultural Sciences, Hangzhou, 310021, China
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Affiliation(s)
- H. Xi
- Key Laboratory of System Bio-medicine of Jiangxi Province, Jiujiang University, Jiujiang, PR China
- College of Animal Science and Technology, Shanxi Agricultural University, Shanxi, PR China
| | - L. Lei
- Key Laboratory of System Bio-medicine of Jiangxi Province, Jiujiang University, Jiujiang, PR China
| | - W. Fu
- Key Laboratory of System Bio-medicine of Jiangxi Province, Jiujiang University, Jiujiang, PR China
- Department of human anatomy, Jiujiang University, Jiujiang, PR China
| | - L. Li
- Key Laboratory of System Bio-medicine of Jiangxi Province, Jiujiang University, Jiujiang, PR China
- Department of human anatomy, Jiujiang University, Jiujiang, PR China
| | - X. Cao
- Key Laboratory of System Bio-medicine of Jiangxi Province, Jiujiang University, Jiujiang, PR China
| | - L. Yang
- Key Laboratory of System Bio-medicine of Jiangxi Province, Jiujiang University, Jiujiang, PR China
- Department of human anatomy, Jiujiang University, Jiujiang, PR China
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Zhang Z, Fan X, Xi H, Ji R, Shen H, Shi A, He J. Effect of local scrotal heating on the expression of tight junction-associated molecule Occludin in boar testes. Reprod Domest Anim 2018; 53:458-462. [PMID: 29330895 DOI: 10.1111/rda.13131] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Accepted: 11/23/2017] [Indexed: 11/30/2022]
Abstract
The aim of this study was to determine whether local scrotal heating (42°C, for 1 hr) had an effect on the expression of tight junction (TJ)-associated molecule Occludin in boar testes. Adult boars (Landrace, n = 6) were used and randomly divided into two groups (n = 3 each). Three boars were given local scrotal exposure to 42°C for approximately 1 h with a home-made electric blanket of controlled temperature as local scrotal heating group, the other three boars received no heat treatment and were left at standard room temperature as control group. After 6 hr, all boars were castrated and the testes were harvested. qRT-PCR, Western blotting and immunohistochemistry were used to explore the expression and localization of Occludin. qRT-PCR and Western blotting showed that the protein and mRNA levels of Occludin significantly decreased in local scrotal heating group as compared to the control. Furthermore, immunoreactivity staining of Occludin was localized at the sites of the blood-testis barrier (BTB) and formed an almost consecutive and strong immunoreactivity strand in the control, while Occludin was limited to Sertoli cells (SCs) and no obvious immunoreactivity strand was present in local scrotal heating group. These data indicated that local scrotal heating decreased the expression of TJ-associated molecule Occludin, which may be involved in heat-induced spermatogenesis damage.
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Affiliation(s)
- Z Zhang
- Institute of Animal Biotechnology, College of Animal Science and Veterinary Medicine, Shanxi Agricultural University, Taigu, China
| | - X Fan
- Institute of Animal Biotechnology, College of Animal Science and Veterinary Medicine, Shanxi Agricultural University, Taigu, China
| | - H Xi
- Institute of Animal Biotechnology, College of Animal Science and Veterinary Medicine, Shanxi Agricultural University, Taigu, China
| | - R Ji
- Institute of Animal Biotechnology, College of Animal Science and Veterinary Medicine, Shanxi Agricultural University, Taigu, China
| | - H Shen
- Institute of Animal Biotechnology, College of Animal Science and Veterinary Medicine, Shanxi Agricultural University, Taigu, China
| | - A Shi
- Landscape Administration, Yangquan, China
| | - J He
- Institute of Animal Biotechnology, College of Animal Science and Veterinary Medicine, Shanxi Agricultural University, Taigu, China
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Xi H, Fan X, Zhang Z, Liang Y, Li Q, He J. Bax and Bcl-2 are involved in the apoptosis induced by local testicular heating in the boar testis. Reprod Domest Anim 2017; 52:359-365. [DOI: 10.1111/rda.12904] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2016] [Accepted: 11/05/2016] [Indexed: 12/11/2022]
Affiliation(s)
- H Xi
- Institute of Animal Biotechnology; College of Animal Science and Technology; Shanxi Agricultural University; Taigu Shanxi China
| | - X Fan
- Institute of Animal Biotechnology; College of Animal Science and Technology; Shanxi Agricultural University; Taigu Shanxi China
| | - Z Zhang
- Institute of Animal Biotechnology; College of Animal Science and Technology; Shanxi Agricultural University; Taigu Shanxi China
| | - Y Liang
- Institute of Animal Biotechnology; College of Animal Science and Technology; Shanxi Agricultural University; Taigu Shanxi China
| | - Q Li
- Institute of Animal Biotechnology; College of Animal Science and Technology; Shanxi Agricultural University; Taigu Shanxi China
| | - J He
- Institute of Animal Biotechnology; College of Animal Science and Technology; Shanxi Agricultural University; Taigu Shanxi China
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Xi H, Shi J, Meng L, Zhou G, Zhou BY, Dong J, Tan X, Liu JH, Wu WB, Shi H, Yu PL. [Application of frailty index for comprehensive geriatric assessment in the elderly in China]. Zhonghua Liu Xing Bing Xue Za Zhi 2017; 37:718-21. [PMID: 27188370 DOI: 10.3760/cma.j.issn.0254-6450.2016.05.027] [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] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
OBJECTIVE To discuss the suitability of frailty index for comprehensive geriatric assessment(FI-CGA)in the elderly in China, and evaluate the application of FI-CGA in China. METHODS A comprehensive geriatric assessment was conducted among 118 old adults receiving health examination, and frailty index was calculated. Clinical frailty scale(CFS)was also used to evaluate the frail status of the old adults. The correlation between FI-CGA value and CFS level of the old adults was analyzed. RESULTS The mean value of FI-CGA was 0.19 ± 0.07, and the average level of CFS was 3.11 ± 1.46. Women had higher mean value of FI-CGA and higher CFS level than men(FI-CGA= 0.20 ± 0.02 for women, 0.19 ± 0.07 for men; CFS =3.40 ± 0.55 for women, 3.10 ± 1.48 for men), but the differences had no significance(t=0.270, 0.452, P=0.788, 0.652). The FI-CGA value and CFS level increased with age(F=10.437, 5.651, P=0.000, 0.001); and there was a positive correlation between FI-CGA value and CFS level(r=0.615, P=0.000). CONCLUSION FI-CGA is an effective model for the quantitative evaluation of the frail status of the elderly, and can be used in the clinical practice of geriatric medicine.
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Affiliation(s)
- H Xi
- Department of Geriatrics, Beijing Hospital, Beijing 100730, China
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Qin H, Cai A, Xi H, Yuan J, Chen L. ZnRF3 induces apoptosis of gastric cancer cells by antagonizing Wnt and Hedgehog signaling. Panminerva Med 2015; 57:167-175. [PMID: 25923840] [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: 06/04/2023]
Abstract
AIM The aim of this paper was to investigate the function an importance of E3-ubiquitin ligase ZnRF3 in the progression of cancer cell growth. METHODS A total of 58 patients (44 males and 14 females) were enrolled in the study and their gastric tumors were removed surgically and were staged by the TNM approach. Among these patients, 43 patients died and 15 survived at the time of this study. The tumors and the paracancerous tissues were examined by immunohostochemistry for the expression of ZnRF3. We assessed the expression of ZnRF3 in gastric tumors and paracancerous tissues from our patients and related this to patient survival. RESULTS A large proportion of malignant cancers of the stomach are gastric adenocarcinoma type. In spite of many studies, the molecular basis for this cancer is still unclear. Deregulated cell proliferative signaling via Wnt/β-catenin and Hedgehog pathways is considered important in the pathogenesis of many cancers including the gastric cancer. Recent studies identified ZnRF3 protein, which is a E3-ubiquitin ligase and which is either deleted or mutated in cancers, to inhibit Wnt signaling. However, the significance of ZnRF3 in the control of gastric cancer and whether it also regulates Hedgehog signaling pathway, is not known. ZnRF3 expression was much higher in tumors from aged patients. Male patients showed higher mortality than the females. Mechanistic studies using normal gastric cells (GES1) and gastric cancer cells (MGC-803) infected with either AdZnRF3 or AdGFP viral vectors, revealed that ZnRF3 overexpression causes significantly more apoptosis and lowered proliferation of cancer cells. ZnRF3 overexpression led to greatly reduced levels of Lgr5, a component of Wnt signaling and also Gli1, a component of Hedgehog signaling. Thus, ZnRF3 negatively influences both the Wnt and Hedgehog proliferative pathways and probably this way it negatively regulates cancer progression. These results suggest the importance of normal ZnRF3 function in checking the progression of cancer cell growth and indicate that a lack of this protein can lead to poorer clinical outcomes for gastric cancer patients. CONCLUSION We observed a clear relationship between ZnRF3 expression in paracancerous tissue and tumor size.
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Affiliation(s)
- H Qin
- General Surgery Department, PLA General Hospital, Beijing, China -
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Li D, Xi H, Yu X, Cai Y. Molecular cloning and characterization of a subtilisin-like protease from Arabidopsis thaliana. Genet Mol Res 2015; 14:16535-45. [DOI: 10.4238/2015.december.9.25] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Wu CB, Xi H, Zhang LM, Zhou Q. Sialendoscopy-assisted treatment of trauma to Stensen's duct: technical note. Br J Oral Maxillofac Surg 2014; 53:102-3. [PMID: 25451072 DOI: 10.1016/j.bjoms.2014.09.022] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2014] [Accepted: 09/24/2014] [Indexed: 10/24/2022]
Affiliation(s)
- C-B Wu
- Department of Oral and Maxillofacial Surgery, School of Stomatology, China Medical University, No. 117, Nanjing North Street, Heping District, Shenyang 110002, Liaoning Province, PR China.
| | - H Xi
- Department of Pediatric Dentistry, School of Stomatology, Jilin University, No. 1500, Qinghua Street, Chaoyang District, Changchun 130021, Jilin Province, PR China.
| | - L-M Zhang
- Department of Oral and Maxillofacial Surgery, School of Stomatology, China Medical University, No. 117, Nanjing North Street, Heping District, Shenyang 110002, Liaoning Province, PR China.
| | - Q Zhou
- Department of Oral and Maxillofacial Surgery, School of Stomatology, China Medical University, No. 117, Nanjing North Street, Heping District, Shenyang 110002, Liaoning Province, PR China.
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Dong H, Zhang Y, Xi H. The Effects of Epidural Anaesthesia and Analgesia on Natural Killer Cell Cytotoxicity and Cytokine Response in Patients with Epithelial Ovarian Cancer Undergoing Radical Resection. J Int Med Res 2012. [PMID: 23206463 DOI: 10.1177/030006051204000520] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Objective: Epidural anaesthesia appears to promote antitumourigenic activity in patients with malignant disease who are undergoing surgery. This study investigated immune function in women with epithelial ovarian cancer undergoing radical resection with either general anaesthesia alone or in combination with epidural anaesthesia. Methods: Patients ( n = 61) were randomized to receive either combined general/epidural anaesthesia (study group) or general anaesthesia alone (control group). Natural killer cell cytotoxicity (NKCC) and serum concentrations of four cytokines (interleukin [IL]-1β, -8 and -10 and interferon [IFN]-γ) were measured before anaesthesia ( Tpre) and 4h after skinincision ( T4 h) in both groups. Results: In both groups, concentrations of protumourigenic cytokines (IL-1β and IL-8) were significantly higher at T4 h than at Tpre, while concentrations of antitumourigenic cytokines (IL-10 and IFN-γ) and NKCC were significantly lower at T4 h. The study group had significantly higher NKCC, IL-10 and IFN-γ levels and lower IL-1β and IL-8 levels at TT h compared with the control group. Conclusion: Combined general/epidural anaesthesia appeared to promote antitumourigenic NKCC and cytokine responses.
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Affiliation(s)
- H Dong
- Department of Anaesthesiology, Second Affiliated Hospital of Harbin Medical University, Harbin, China
| | - Y Zhang
- Department of Anaesthesiology, Second Affiliated Hospital of Harbin Medical University, Harbin, China
| | - H Xi
- Department of Anaesthesiology, Second Affiliated Hospital of Harbin Medical University, Harbin, China
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Xi H, Mao Y, Wang X, Zeng Q, Feng Y. Allogeneic bone marrow mesenchymal stem cells over-expressing gap junction protein connexin 43 reduce ventricular arrhythmias following myocardial infarction in rats. Heart 2011. [DOI: 10.1136/heartjnl-2011-300867.16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Wang G, Fu B, Sun T, Cui S, Cao R, Feng L, Xiong L, Wang D, Xie P, Xi H. UP-1.004: Retroperitoneoscopic Versus Open Surgical Renal Pedicle Lymphatic Dissection for Chyluria: A Ten-Year Experience. Urology 2009. [DOI: 10.1016/j.urology.2009.07.451] [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: 10/20/2022]
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Fu B, Wang G, Sun T, Cui S, Cao R, Feng L, Xi H, Chen Q, Xiong J. MP-05.12: Three-Stage Training Model for Laparoscopic Nephron-Sparing Nephrectomy. Urology 2009. [DOI: 10.1016/j.urology.2009.07.1015] [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: 10/20/2022]
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Fu B, Wang G, Cui S, Sun T, Cao R, Feng L, Sun X, Chen J, Xi H, Chen Q, Zhong K, Kuang R. MP-04.05: Extraperitoneal Laparoscopic Surgery for the Treatment of Lower Ureteral Disease. Urology 2009. [DOI: 10.1016/j.urology.2009.07.1027] [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: 11/29/2022]
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Fu B, Wang G, Sun T, Cao R, Cui S, Feng L, Sun X, Xi H, Chen J, Chen Q. MP-04.03: Anatomical Retroperitoneoscopic Adrenalectomy: Initial Experience in 60 Cases. Urology 2009. [DOI: 10.1016/j.urology.2009.07.1025] [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: 11/28/2022]
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Fu B, Wang G, Cui S, Sun T, Cao R, Feng L, Kuang R, Xi H, Chen Q, Zhong Z, Sun X, Chen J, Xiong L, Wang D, Xie P, Liu T. UP-1.023: Retroperitoneal Laparoscopic Surgery for the Treatment of Large Adrenal Tumors. Urology 2009. [DOI: 10.1016/j.urology.2009.07.470] [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: 10/20/2022]
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Fu B, Wang G, Sun T, Cui S, Cao R, Feng L, Chen W, Xi H. MP-04.04: Techniques for Reducing Renal Warm Ischemia Time for Laparoscopic Nephron-Sparing Surgery. Urology 2009. [DOI: 10.1016/j.urology.2009.07.1026] [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: 10/20/2022]
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Yu L, Tao J, Sun Y, Xi H, Huang J, Ediger M. What do polymorphs teach us about crystal nucleation and growth? Acta Crystallogr A 2008. [DOI: 10.1107/s0108767308095639] [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: 11/10/2022] Open
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Ling FC, Baldus SE, Khochfar J, Xi H, Neiss S, Brabender J, Metzger R, Drebber U, Dienes HP, Bollschweiler E, Hoelscher AH, Schneider PM. Association of COX-2 expression with corresponding active and chronic inflammatory reactions in Barrett's metaplasia and progression to cancer. Histopathology 2007; 50:203-9. [PMID: 17222248 DOI: 10.1111/j.1365-2559.2007.02576.x] [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] [Indexed: 02/06/2023]
Abstract
AIMS Risk reduction for Barrett's cancer in individuals taking non-steroidal anti-inflammatory drugs has been reported. Cyclooxygenase (COX)-2, one of the inhibited enzymes, is putatively involved in Barrett's cancer pathogenesis. The aim of this study was to examine a possible association between COX-2 protein expression and the development and progression of the Barrett's metaplasia-dysplasia-carcinoma sequence and the type and degree of associated inflammatory reaction. METHODS AND RESULTS Squamous epithelium, metaplastic, low-grade, high-grade dysplastic lesions and tumour tissue of 49 resection specimens from patients with Barrett's adenocarcinoma were immunohistochemically analysed. Active and chronic inflammatory reactions were classified according to the Updated Sydney System. Within the Barrett's sequence, a significant progressive increase in COX-2 expression was identified (P < 0.0001). The most significant differences were detected between squamous epithelium and Barrett's metaplasia (P < 0.001) and from low- to high-grade dysplasia (P < 0.0001). Active and chronic inflammation were significantly different between squamous epithelium and Barrett's metaplasia (P < 0.0001), but not during further progression in the sequence. CONCLUSIONS Increasing COX-2 expression in Barrett's metaplasia is significantly associated with a change in the local inflammatory reaction, but not during further progression through dysplasia to cancer. This supports the potential of a chemoprevention strategy using COX-2 inhibitors independent of the extent and type of the inflammatory reaction in Barrett's oesophagus.
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Affiliation(s)
- F C Ling
- Department of Visceral and Vascular Surgery, University of Cologne, Cologne [corrected] Germany
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Richter A, Pladevall M, Manjunath R, Lafata JE, Xi H, Simpkins J, Brar I, Markowitz N, Iloeje UH, Irish W. Patient characteristics and costs associated with dyslipidaemia and related conditions in HIV-infected patients: a retrospective cohort study. HIV Med 2005; 6:79-90. [PMID: 15807713 DOI: 10.1111/j.1468-1293.2005.00269.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [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: 11/30/2022]
Abstract
BACKGROUND Metabolic abnormalities are common in HIV-infected individuals and, although multifactorial in origin, have been strongly associated with antiretroviral therapy. METHODS Using automated claims and clinical databases, combined with medical record data, we evaluated the burden of dyslipidaemia (DYS) and associated metabolic abnormalities among a cohort of 900 HIV-infected patients aged 18 years and older who received their care from a large multispecialty medical group between 1 January 1996 and 30 June 2002. A Cox proportional hazards model for DYS was developed. Resource use was compiled and subsequently costed with stratification to account for variable length of follow-up. RESULTS Mean follow-up time was 3.3 years. DYS was present in 54% of the cohort and 3.4% experienced a cardiovascular (CV) event. Both unadjusted and adjusted results found patients with dyslipidaemia and cardiovascular events significantly more likely to have received protease inhibitor (PI) treatment for longer periods of time. In the Cox proportional hazards model the following factors were significantly associated with an increased risk for DYS: older age, white race, PI use and male sex. Diagnoses of hypertension, hepatitis C virus infection, depression or opportunistic infections were all negatively associated with a DYS diagnosis. When controlled for length of follow up, patients with DYS (and no CV-related events) incurred greater median and mean total average costs than patients without DYS or CV-related events. For patients with more than 2 years of follow up, these total cost differences were statistically significant (P<0.05). CONCLUSIONS These findings indicate that DYS is common among patients with HIV infection and is associated with increased use of medical resources.
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Affiliation(s)
- A Richter
- Defences Resources Management Institute, Naval Postgraduate School, Monterey, CA 93943, USA.
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Abstract
Aminoglycosides, traditional RNA binders, were found to be a new class of triple helical nucleic acid-stabilizing ligands. Neomycin, of all the aminoglycosides, has shown the most significant effects in stabilizing DNA, RNA, and hybrid triple helices. When compared with minor groove binders or intercalators, neomycin excels at triple helical stabilization in most cases. Molecular modeling studies suggest that neomycin reaches into the larger Watson-Hoogsteen groove. The charge and shape complementarity are the key factors in neomycin-triplex recognition. By conjugating neomycin with intercalators such as BQQ (a potent triple helix intercalating agent designed by Hélène), we have progressed in developing more potent triple helix stabilizing ligands. The design of such dual or even triple recognition ligands opens a new paradigm for recognition of triple helix nucleic acids. The article herein presents studies of neomycin as the first molecule that can selectively stabilize nucleic acid triplex structures. These studies are supported by our recent discovery that neomycin prefers to bind to A-like conformations, of which triple helix structures are known to display some characteristics. These findings will contribute to the development of a new series of triplex-specific ligands, and may contribute to either antisense or antigene therapies.
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Affiliation(s)
- H Xi
- Laboratory of Medicinal Chemistry, Department of Chemistry, Clemson University, Clemson, South Carolina, 29634, USA
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Williams L, Pladevall M, Xi H, Peterson E, Joseph C, Elston Lafata J, Ownby D, Johnson C. Relationship between adherence to inhaled corticosteroids and poor outcomes among adults with asthma. J Allergy Clin Immunol 2005. [DOI: 10.1016/j.jaci.2004.12.1102] [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: 10/25/2022]
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Xi H, Goodwin B, Shepherd AT, Blanck G. Impaired class II transactivator expression in mice lacking interferon regulatory factor-2. Oncogene 2001; 20:4219-27. [PMID: 11464288 DOI: 10.1038/sj.onc.1204556] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [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] [Received: 10/16/2000] [Revised: 04/12/2001] [Accepted: 04/18/2001] [Indexed: 11/09/2022]
Abstract
Class II transactivator (CIITA) is required for both constitutive and inducible expression of MHC class II genes. IFN-gamma induced expression of CIITA in various cell types is directed by CIITA type IV promoter. The two transactivators, STAT1 and IRF-1, mediate the IFN-gamma activation of the type IV promoter by binding to the GAS and IRF-E of the promoter, respectively. In addition to IRF-1, IRF-2, another member of the IRF family, also activates the human CIITA type IV promoter, and IRF-2 cooperates with IRF-1 to activate the promoter in transient transfection assays. IRF-1 and IRF-2 can co-occupy the IRF-E of the human CIITA type IV promoter. To understand the effect of loss of IRF-2 on the endogenous CIITA expression, we assayed for CIITA expression in IRF-2 knock-out mice. Both basal and IFN-gamma induced CIITA expression were reduced in IRF-2 knock-out mice. At least half of the amount of inducible CIITA mRNA depends on IRF-2. The reduction of IFN-gamma induced CIITA mRNA in IRF-2 knock-out mice was due to the reduction of the type IV CIITA mRNA induction. The reduction of basal CIITA mRNA was apparently due to the reduction of CIITA mRNA originating from other promoters. These data indicate that IRF-2, like IRF-1, plays a critical role in the regulation of the endogenous CIITA gene. The implications in understanding the previously described phenotypes of IRF-2 defective mice are discussed.
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Affiliation(s)
- H Xi
- Department of Biochemistry and Molecular Biology, College of Medicine, University of South Florida, Tampa, Florida, FL33612, USA
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Goodwin BL, Xi H, Tejiram R, Eason DD, Ghosh N, Wright KL, Nagarajan U, Boss JM, Blanck G. Varying functions of specific major histocompatibility class II transactivator promoter III and IV elements in melanoma cell lines. Cell Growth Differ 2001; 12:327-35. [PMID: 11432807] [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] [Subscribe] [Scholar Register] [Indexed: 04/16/2023]
Abstract
Melanoma cells commonly express MHC class II molecules constitutively. This is a rare, or possibly unique, phenotype for a nonprofessional antigen-presenting cell, where MHC class II expression ordinarily occurs only after IFN-gamma treatment. Despite the fact that constitutive expression of MHC class II on melanoma cells has been observed for decades and that the regulation of the MHC class II genes is well understood for many different cell types, there is no data regarding the basis for constitutive MHC class II expression in melanoma cells. Here we report that MHC class II expression in melanoma cells can be traced to constitutive expression of the class II transactivator protein (CIITA), which mediates both IFN-gamma-inducible and -constitutive MHC class II expression in all other cell types. In addition, we determined that constitutive CIITA expression is the result of the activation of both the B cell-specific CIITA promoter III and the IFN-gamma-inducible CIITA promoter IV, the latter of which previously has never been known to function as a constitutive promoter in any cell type. The recently described B cell-related ARE-1 activity is important for promoter III activation in the melanoma cells. Constitutive promoter IV activation involves the IFN regulatory factor element (IRF-E), which binds members of the IRF family of proteins, although the major, IFN-gamma inducible member of this family, IRF-1, is not constitutively expressed in these cells. In cells with constitutively active promoter IV, the promoter IV IRF-E is most likely activated by IRF-2. The relevance of these results to the pathway of melanoma development is discussed.
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Affiliation(s)
- B L Goodwin
- Department of Biochemistry and Molecular Biology, College of Medicine and Immunology Program, H. Lee Moffitt Cancer Center and Research Institute, University of South Florida, Tampa, Florida 33612, USA
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Lafata JE, Martin S, Morlock R, Divine G, Xi H. Provider type and the receipt of general and diabetes-related preventive health services among patients with diabetes. Med Care 2001; 39:491-9. [PMID: 11317097 DOI: 10.1097/00005650-200105000-00009] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [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: 11/26/2022]
Abstract
OBJECTIVE Using a measure of provider type that includes "shared care" to determine the contribution of provider type on receipt of general and diabetes-related preventive health services. METHODS Automated clinical and administrative data were used to identify adult patients with type 1 and 2 diabetes receiving care from a multispecialty, salaried group practice and enrolled in a large health maintenance organization between 3/97 and 2/98 (n = 10,991). Logistic regression models were fit using generalized estimating equation approaches to evaluate the contribution of provider type on service receipt. MEASURES Preventive service receipt included receipt of glycated hemoglobin and lipid testing, retinal examinations, pneumococcal vaccines, Papanicolaou (Pap) smears, and mammograms. Multivariable analyses adjusted for age, sex, race, marital status, household income, diabetes-related comorbidities and complications, prescription drug use, laboratory testing results, and frequency of medical care contact. RESULTS Patients seeing an endocrinologist and primary care physician (PCP) were more likely than those seeing endocrinologists alone to receive glycated hemoglobin testing (OR, 1.42), lipid testing (OR, 1.72), mammograms (OR, 2.12), and Pap smears (OR, 2.36), and more likely than those seeing PCPs alone to receive glycated hemoglobin testing (OR, 1.79), lipid testing (OR, 1.54), retinal examinations (OR, 1.33), and mammograms (OR, 1.43). Compared with patients seeing PCPs only, patient's seeing endocrinologists only were more likely to receive retinal examinations (OR, 1.37) and less likely to receive Pap smears (OR, 0.46). CONCLUSIONS Care delivered by no one single provider type is associated with greater receipt of all recommended services. Instead, patients seeing both an endocrinologist and a PCP are most likely to receive recommended services.
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Affiliation(s)
- J E Lafata
- Henry Ford Health System, Detroit, Michigan, USA.
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Xi H, Shin WS, Suzuki J, Nakajima T, Kawada T, Uehara Y, Nakazawa M, Toyo-oka T. Dystrophin disruption might be related to myocardial cell apoptosis caused by isoproterenol. J Cardiovasc Pharmacol 2001; 36 Suppl 2:S25-9. [PMID: 11206716 DOI: 10.1097/00005344-200000006-00007] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Sarcolemma integrity is stabilized by the dystrophin-associated glycoprotein complex that connects actin and laminin-2 in contractile machinery and the extracellular matrix, respectively. Interruption of the connection by the primary gene defect or acquired pathological burden can cause cardiac failure. The purposes of the present study were to verify whether dystrophin is disrupted in acute myocardial injury after the isoproterenol overload (10 mg/kg) and to examine its relation to myocardial cell apoptosis in rats. This injury from 4-16 h at the subendocardium was accompanied by dystrophin disruption and dislocation from subsarcolemma to cytoplasm, which were confirmed by immunohistology and Western blotting. However, delta-sarcoglycan was thoroughly preserved in sarcolemma. The dystrophin degradation preceded the appearance of apoptotic cells and exactly coincided with the transferase-mediated dUTP-biotin nick end labeling-positive cardiomyocytes (TUNEL), as was verified by double-staining. These data suggest that beta-adrenergic stimulation induces dystrophin breakdown followed by apoptosis.
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Affiliation(s)
- H Xi
- Department of Internal Medicine, Tokyo University Hospital, University of Tokyo, Japan
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Abstract
Escherichia coli is not known to utilize purines, other than adenine and adenosine, as nitrogen sources. We reinvestigated purine catabolism because a computer analysis suggested several potential sigma(54)-dependent promoters within a 23-gene cluster whose products have homology to purine catabolic enzymes. Our results did not provide conclusive evidence that the sigma(54)-dependent promoters are active. Nonetheless, our results suggest that some of the genes are metabolically significant. We found that even though several purines did not support growth as the sole nitrogen source, they did stimulate growth with aspartate as the nitrogen source. Cells produced (14)CO(2) from minimal medium containing [(14)C]adenine, which implies allantoin production. However, neither ammonia nor carbamoyl phosphate was produced, which implies that purine catabolism is incomplete and does not provide nitrogen during nitrogen-limited growth. We constructed strains with deletions of two genes whose products might catalyze the first reaction of purine catabolism. Deletion of one eliminated (14)CO(2) production from [(14)C]adenine, which implies that its product is necessary for xanthine dehydrogenase activity. We changed the name of this gene to xdhA. The xdhA mutant grew faster with aspartate as a nitrogen source. The mutant also exhibited sensitivity to adenine, which guanosine partially reversed. Adenine sensitivity has been previously associated with defective purine salvage resulting from impaired synthesis of guanine nucleotides from adenine. We propose that xanthine dehydrogenase contributes to this purine interconversion.
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Affiliation(s)
- H Xi
- Department of Molecular and Cell Biology, The University of Texas at Dallas, Richardson, Texas 75083-0688, USA
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Xi H, Blanck G. Interferon regulatory factor-2 point mutations in human pancreatic tumors. Int J Cancer 2000; 87:803-8. [PMID: 10956389] [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: 02/17/2023]
Abstract
Interferon regulatory factor (IRF)-2, a member of the IRF family, is a transcription factor involved in the regulation of various interferon and virus-stimulated genes and other genes. For example, IRF-2 is an activator of the interferon (IFN)-gamma-inducible MHC class II transactivator (CIITA) type IV promoter. It cooperates with IRF-1 in the activation of the CIITA type IV promoter and can co-occupy the IRF-E of the promoter with IRF-1. In a previous study, we identified an inactivating point mutation in the DNA binding domain of IRF-2 expressed in a human pancreatic tumor cell line that does not express CIITA or MHC class II in response to IFN-gamma. To further assess the potential impact of IRF-2 mutations in tumorigenesis, we screened fresh pancreatic tumor explants and identified 2 IRF-2 point mutations in the 2 alleles of IRF-2 from a single tumor specimen. Both mutations occurred in the DNA binding domain of IRF-2. DNA binding assays demonstrated that the IRF-2 point mutations impaired IRF-2 DNA binding. The transactivation function of the mutant IRF-2s was similarly impaired. This is the first report of IRF-2 mutations in human tumor explants.
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Affiliation(s)
- H Xi
- Department of Biochemistry and Molecular Biology, College of Medicine, University of South Florida, Tampa, Florida 33612, USA
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Wang HY, Zhang FC, Gao JJ, Fan JB, Liu P, Zheng ZJ, Xi H, Sun Y, Gao XC, Huang TZ, Ke ZJ, Guo GR, Feng GY, Breen G, Clair DS, He L. Apolipoprotein E is a genetic risk factor for fetal iodine deficiency disorder in China. Mol Psychiatry 2000; 5:363-8. [PMID: 10889546 DOI: 10.1038/sj.mp.4000735] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [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
Fetal iodine deficiency disorder (FIDD) is the principal form of endemic cretinism, and the most common cause of preventable mental deficiency in the world. However not everyone at risk develops FIDD and familial aggregation is common. This suggests that genetic factors may also be involved. The Apolipoprotein E (APOE) gene encodes for a lipoprotein that possesses a thyroid hormone binding domain, and APOE genotype may affect the efficiency with which thyroid hormone influences neuronal cell growth during the first and second trimesters of fetal development. We have compared ApoE genotypes in 91 FIDD cases with 154 local control subjects, recruited from three iodine deficiency areas in central China. We have also genotyped 42 FIDD family cases and 158 normal individuals from the families of local controls, and 375 population controls from Shanghai. APOE epsilon4 genotypes were significantly enriched in FIDD probands from each of the three iodine deficiency areas; the epsilon4 allele frequency was 16% vs 6% in controls. The same effect was also observed when we compared FIDD family cases with controls and control families. Our data suggest that in iodine-deficient areas, the APOE epsilon4 allele is a genetic risk factor for FIDD. The phenomenon may affect population selection and contribute to the low frequency of the epsilon4 allele in Chinese compared to Caucasian populations.
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Affiliation(s)
- H Y Wang
- Shanghai Institute of Physiology, Chinese Academy Sciences, Shanghai 200031, People's Republic of China
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Xi H, Eason DD, Ghosh D, Dovhey S, Wright KL, Blanck G. Co-occupancy of the interferon regulatory element of the class II transactivator (CIITA) type IV promoter by interferon regulatory factors 1 and 2. Oncogene 1999; 18:5889-903. [PMID: 10557076 DOI: 10.1038/sj.onc.1202969] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.5] [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
Class II transactivator (CIITA) activates the expression of major histocompatibility class II genes, which encode antigen-presenting molecules recognized by the T-cell receptor of CD4+ T cells. IFN-gamma induced CIITA transcription in many cell types is directed by the CIITA Type IV promoter. Here we report that the human CIITA Type IV promoter IRF-E binds IRF-1 and can be activated by exogenous expression of IRF-1. Surprisingly, the CIITA Type IV promoter IRF-E is also activated by IRF-2, another member of the IRF family that generally acts as a transcriptional repressor. In addition, we found that IRF-1 and IRF-2 synergistically activate the CIITA Type IV promoter. Electrophoretic mobility shift assays revealed that IRF-1 and IRF-2 can simultaneously occupy the IRF-E of the CIITA Type IV promoter, suggesting a novel mechanism for the role of these two proteins in promoter activation. Our results also indicate that IRF-1 and IRF-2 can cooperatively activate and co-occupy the IRF-E of the guanylate binding protein (GBP) promoter. Finally, CIITA induction by IFN-gamma does not occur in a pancreatic tumor cell line that expresses a mutated IRF-2, representing the first IRF-2 mutation identified in a human tumor cell line.
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Affiliation(s)
- H Xi
- Department of Biochemistry, College of Medicine, University of South Florida, Tampa, Florida, FL 33612, USA
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Xi H, Peng G, Chou SH. Finite-volume lattice Boltzmann schemes in two and three dimensions. Phys Rev E Stat Phys Plasmas Fluids Relat Interdiscip Topics 1999; 60:3380-8. [PMID: 11970153 DOI: 10.1103/physreve.60.3380] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/1999] [Revised: 04/07/1999] [Indexed: 04/18/2023]
Abstract
Simple and practical finite-volume schemes for the lattice Boltzmann equation are derived in two and three dimensions through the application of modern finite-volume methods. The schemes use a finite-volume vortex-type formulation based on quadrilateral elements in two dimensions and trilinear hexahedral elements in three dimensions. It is shown that the schemes are applicable to domains with irregular boundaries of arbitrary shape in two and three dimensions.
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Affiliation(s)
- H Xi
- Department of Physics and Astronomy, Bowling Green State University, Bowling Green, Ohio 43403, USA
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Xi H, Peng G, Chou SH. Finite-volume lattice Boltzmann method. Phys Rev E Stat Phys Plasmas Fluids Relat Interdiscip Topics 1999; 59:6202-5. [PMID: 11969609 DOI: 10.1103/physreve.59.6202] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/1998] [Revised: 12/15/1998] [Indexed: 04/18/2023]
Abstract
We present a finite-volume formulation for the lattice Boltzmann method (FVLBM) based on standard bilinear quadrilateral elements in two dimensions. The accuracy of this scheme is demonstrated by comparing the velocity field with the analytical solution of the Navier-Stokes equations for time dependent rotating Couette flow and Taylor vortex flow. To demonstrate the flexibility of the scheme, we have also simulated a modified rotating Couette flow, where the inner cylinder has an elliptical shape. The results agree with those obtained from the traditional marker-and-cell method. The FVLBM scheme is applicable to arbitrarily shaped two-dimensional regions, and thus the range of applicability of the lattice Boltzmann method has been significantly extended.
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Affiliation(s)
- H Xi
- Department of Physics and Astronomy, Bowling Green State University, Bowling Green, Ohio 43403, USA
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Lu X, Zhang S, Xi H. [Treatment of lingual angiocavernoma by selective arteriocatheterization with urea injection]. Lin Chuang Er Bi Yan Hou Ke Za Zhi 1997; 11:451-3. [PMID: 10323011] [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: 02/12/2023]
Abstract
Selective arteriocatheterization with urea injection was administered to 36 cases of lingual angiocavernoma. There were 20 males and 16 females, ranging in age from 6 to 18 years with an average of 12 years. Two to five mililiters of 40% urea were injected once a day for 10-15 days as a course of treatment, 29 cases (80.6%) were cured in one course of treatment. The other 7 cases (19.4%) were cured in the 2nd course of treatment. The results suggest that selective arteriocatheterization with urea injection is a safe, convenient and effective technique in the treatment of ingual angiocavernoma.
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Affiliation(s)
- X Lu
- Department of Otolaryngology-Head and Neck Surgery, People's Hospital, Liaocheng Prefecture, Shandong Province
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Xi H, Lynch WG, Tsang MB, Friedman WA. Secondary decays and the helium lithium isotope thermometer. Phys Rev C Nucl Phys 1996; 54:R2163-R2166. [PMID: 9971651 DOI: 10.1103/physrevc.54.r2163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Xi H, Gunton JD. Spatiotemporal chaos in a model of Rayleigh-Bénard convection. Phys Rev E Stat Phys Plasmas Fluids Relat Interdiscip Topics 1995; 52:4963-4975. [PMID: 9963992 DOI: 10.1103/physreve.52.4963] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Abstract
Verapamil has beneficial effects on ischemic myocardium, including reduction in electrophysiological derangements, prevention of intracellular K+ loss, and preservation of high-energy phosphates, but the mechanisms underlying these actions are not clear. Recent studies have demonstrated a role of ATP-regulated K+ (KATP) current in action potential shortening and K+ loss during ischemia and metabolic inhibition. Therefore, we studied the effects of verapamil on KATP current in feline ventricular myocytes to test the hypothesis that the drug prevents ischemic electrophysiological disturbances by affecting the KATP channel. Membrane potentials and currents were recorded using standard patch-clamp techniques. During 15-minute superfusion with 1 mM CN-, action potential duration measured at 90% repolarization was reduced from 259 +/- 12 to 98 +/- 15 msec (62% reduction) in the absence of verapamil and from 266 +/- 11 to 183 +/- 16 msec (31% reduction) in the presence of 2 microM verapamil (p less than 0.01). In inside-out membrane patches, the KATP current, activated in the absence of ATP, was significantly suppressed by intracellular application of 2 microM verapamil, but the single-channel conductance was not changed. Verapamil did not change the mean open and closed times of the channel within bursts (e.g., the mean open time was 1.92 +/- 0.18 and 1.82 +/- 0.21 msec in the absence and presence of 2 microM verapamil, respectively), but it shortened the mean lifetime of bursts from 41.1 +/- 3.5 to 24.9 +/- 2.8 msec (p less than 0.01) and prolonged the closed time between bursts from 39.4 +/- 4.6 to 78.5 +/- 5.1 msec (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- S Kimura
- Department of Medicine, University of Miami School of Medicine, FL 33101
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Abstract
BACKGROUND Cocaine may produce life-threatening cardiac arrhythmias, but it is not clear whether this is an indirect effect of coronary vasoconstriction and ischemia or a direct myocardial effect of the substance. Except for its effects on the Na+ current as a local anesthetic, little is known about the direct electrophysiological actions on cardiac cells. Therefore, we studied the effects of cocaine on action potentials and membrane currents in isolated feline ventricular myocytes to test the hypothesis that cocaine-induced arrhythmogenesis may be based on cellular and ionic mechanisms. METHODS AND RESULTS Action potentials and membrane currents were recorded using the patch clamp technique. Single cells were isolated from feline left ventricles by enzymatic digestion. Exposure to cocaine (10 or 50 microM) depressed the plateau phase of the action potential and prolonged action potential duration. Action potential duration measured at 90% repolarization (APD90) was increased from 280 +/- 12 msec to 325 +/- 17 msec (p less than 0.01) by 5-minute exposure to 10 mumol cocaine, when the cells were stimulated at 1 Hz. During exposure to 50 mumol cocaine, APD90 was markedly increased from 298 +/- 13 msec to 437 +/- 35 msec (p less than 0.01) in seven of 16 cells, and early afterdepolarizations (EADs) developed in these cells. The take-off potential and the amplitude of EADs were -28.3 +/- 2.3 mV and 16.8 +/- 1.2 mV, respectively. Triggered activity arising from EADs was induced in four of the seven cells. Addition of 1 nmol isoproterenol augmented EADs and induced sustained triggered activity, whereas they were suppressed by exposure to 2 microM verapamil. Whole-cell voltage clamp experiments revealed that cocaine (50 microM) reduced the peak L-type Ca2+ current from 1.03 +/- 0.13 nA to 0.79 +/- 0.11 nA (23% reduction, p less than 0.05). Cocaine also reduced the peak delayed rectifier K+ current from 362 +/- 51 pA to 113 +/- 32 pA (69% reduction, p less than 0.01). However, cocaine did not affect activation and inactivation kinetics of these channels. Cocaine had no effect on the inward rectifier K+ current. CONCLUSIONS We conclude that cocaine can prolong action potential duration and induce EADs and triggered activity by blocking the delayed rectifier K+ current, and that cocaine-induced abnormalities of repolarization, modulated by its inhibitory effects on catecholamine reuptake, may play a role in the potential of cocaine for induction of acute fatal arrhythmias.
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Affiliation(s)
- S Kimura
- Department of Medicine (Division of Cardiology), University of Miami School of Medicine, FL 33101
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Huang E, Xu M, Yang J, Xi H, Xu D. [Chemical studies on the constituents of Daphne koreane Nakai]. Zhongguo Zhong Yao Za Zhi 1990; 15:609-10, 640. [PMID: 2268398] [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: 12/31/2022]
Abstract
In this paper three compounds isolated from Daphne koreane are described. Their structures have been identified as beta-sitosterol, naringenin and 7,8-dimethoxycoumarin on the basis of spectral data and chemical reactions.
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Affiliation(s)
- E Huang
- Institute of Traditional Chinese Medicine and Materia Medica of Jilin Province, Changchun
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