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Wu JS, Jin XR, Wang H, Feng Z, Zhang DN, Li XC. [Analysis of Carbon Emissions and Influencing Factors in China Based on City Scale]. Huan Jing Ke Xue 2023; 44:2974-2982. [PMID: 37177969 DOI: 10.13227/j.hjkx.202205326] [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: 05/15/2023]
Abstract
Assessing regional carbon emissions and their relationship with socio-economic conditions is very important for developing strategies for carbon emission reduction. This study explored the impact of the proportion of non-fossil energy, the land development degree, the urbanization rate of permanent residents, the proportion of secondary industry, per capita GDP, and per capita construction land area on per capita CO2 emissions in 339 prefecture-level and above cities in China (excluding some cities in Xinjiang, Hong Kong, Macao, and Taiwan). A Bayesian belief network modeling carbon emissions was constructed to identify the global effects of various factors on per capita CO2 emissions, and multiscale geographically weighted regression was used to analyze their local effects. The results showed that first, per capita CO2 emissions of cities in China increased from the south to the north and decreased from the eastern coast to the inland region. Second, globally, the sensitivity of per capita CO2 emissions to various factors from high to low was in the order of per capita construction land area>per capita GDP>urbanization rate of permanent residents>land development degree>proportion of secondary industry>proportion of non-fossil energy. Third, locally, the direction of the spatial relationship between each factor and per capita CO2 emissions was consistent with the global relationship, and there was spatial heterogeneity in the strength of the relationship. Finally, clean energy, decarbonization technologies, saving and intensive use of land, and green living were effective ways to achieve the dual-carbon goal.
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Affiliation(s)
- Jian-Sheng Wu
- School of Urban Planning and Design, Peking University, Shenzhen 518055, China
| | - Xue-Ru Jin
- School of Urban Planning and Design, Peking University, Shenzhen 518055, China
| | - Han Wang
- School of Urban Planning and Design, Peking University, Shenzhen 518055, China
| | - Zhe Feng
- School of Land Science and Technology, China University of Geosciences, Beijing 100083, China
| | - Dan-Ni Zhang
- School of Urban Planning and Design, Peking University, Shenzhen 518055, China
| | - Xue-Chen Li
- School of Urban Planning and Design, Peking University, Shenzhen 518055, China
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Zhang SX, Zhang JM, Zhang WK, Zhang DN, Fu JY, Zang CF. [Spatiotemporal variability characteristics and driving forces of land use in the Pan-Pearl River Basin, China]. Ying Yong Sheng Tai Xue Bao 2020; 31:573-580. [PMID: 32476351 DOI: 10.13287/j.1001-9332.202002.017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
The Pan-Pearl River Basin is a bridgehead for China's reform and opening-up and the construction of the Belt and Road at Sea, with vital strategic significance in Chinese overall development. Land use data and climate and socio-economic indicators were integrated to probe the spatiotemporal change and its driving forces of land use in the Pan-Pearl River basin with ArcGIS spatial analysis tool and SPSS factor analysis tool. Results showed that land use in the Pan-Pearl River Basin significantly changed between 1990 and 2015, with decreases of the area of paddy field and woodland and rapid increases of urban land and other construction land. Outflow of grassland occurred in the northwestern part of the basin. Reduction of cultivated field was mainly concentrated in the central part of the basin and coastal areas. Increases in urban and rural land, industrial and mining land, and residential land were centrally distributed in the Guangdong-Hong Kong-Marco Greater Bay Area. The prominent change areas were Guangdong-Hong Kong-Marco Greater Bay Area : central and southeast of Guangxi Province : northern Hainan Province. Land use changes during 1990-2000 were most obvious in the basin. The main driving factor of spatiotemporal variation of land use was the rapid development of social economy and industry and the improvement of residents' consumption level.
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Affiliation(s)
- Shi-Xiao Zhang
- School of Geography, South China Normal University, Guangzhou 510631, China
| | - Jun-Mao Zhang
- School of Geography, South China Normal University, Guangzhou 510631, China
| | - Wen-Kang Zhang
- School of Geography, South China Normal University, Guangzhou 510631, China
| | - Dan-Ni Zhang
- School of Geography, South China Normal University, Guangzhou 510631, China
| | - Jia-Yi Fu
- School of Geography, South China Normal University, Guangzhou 510631, China
| | - Chuan-Fu Zang
- School of Geography, South China Normal University, Guangzhou 510631, China
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Wang F, Guo XY, Zhang DN, Wu Y, Wu T, Chen ZG. Ultrasound-assisted extraction and purification of taurine from the red algae Porphyra yezoensis. Ultrason Sonochem 2015; 24:36-42. [PMID: 25542513 DOI: 10.1016/j.ultsonch.2014.12.009] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2014] [Revised: 10/20/2014] [Accepted: 12/12/2014] [Indexed: 05/05/2023]
Abstract
The present study reports on the development of a method using ultrasound-assisted extraction (UAE) during the purification of taurine from Porphyra yezoensis. The Box-Behnken design, which is a widely used form of response surface methodology, was used to investigate the effects of parameters on the UAE process. Three independent variables of taurine purification using UAE were studied including: extraction time, temperature, and ultrasonic power. The results showed that the highest taurine yield of 13.0mg/g was obtained with an extraction time of 38.3 min, the use of 300.0 W ultrasonic power, and an extraction temperature of 40.5°C. A comparative study of taurine extraction was also conducted using either ultrasonication or mechanical agitation. The results indicated that the ultrasonic process required 9 times less time at 40°C to obtain taurine with a similar yield as compared to the conventional extraction method. Therefore, UAE can used as an alternative to the conventional extraction method used during the recovery of taurine from P. yezoensis. The UAE method has several advantages, including that it uses lower extraction temperatures and has a shorter extraction time. The taurine present in the extract supernatant was efficiently separated and purified using a combination of 732 cation exchange chromatography and crystallization. The yield of purified taurine using this process was 1.1%. The structure of the purified taurine was confirmed by FTIR, MS, and NMR. Our findings suggest that P. yezoensis can be used as a taurine-rich food or food material.
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Affiliation(s)
- Fen Wang
- College of Food Science & Technology, Nanjing Agricultural University, Nanjing 210095, PR China
| | - Xiao-Yu Guo
- College of Food Science & Technology, Nanjing Agricultural University, Nanjing 210095, PR China
| | - Dan-Ni Zhang
- College of Food Science & Technology, Nanjing Agricultural University, Nanjing 210095, PR China
| | - Yue Wu
- College of Food Science & Technology, Nanjing Agricultural University, Nanjing 210095, PR China
| | - Tao Wu
- College of Food Science & Technology, Nanjing Agricultural University, Nanjing 210095, PR China
| | - Zhi-Gang Chen
- College of Food Science & Technology, Nanjing Agricultural University, Nanjing 210095, PR China.
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Zhang DN, Guo XY, Yang QH, Chen ZG, Tao LJ. An efficient enzymatic modification of cordycepin in ionic liquids under ultrasonic irradiation. Ultrason Sonochem 2014; 21:1682-1687. [PMID: 24631444 DOI: 10.1016/j.ultsonch.2014.02.023] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2014] [Revised: 02/21/2014] [Accepted: 02/21/2014] [Indexed: 06/03/2023]
Abstract
A comparative study of the immobilized Candida antarctica lipase B (Novozym 435)-catalyzed acylation of cordycepin with vinyl acetate in ionic liquids (ILs) under ultrasonic irradiation and shaking was conducted. The application of ultrasonic irradiation instead of shaking during acylation resulted in an enhanced reaction rate and a higher level of substrate conversion. Among the various ILs examined, 1-butyl-3-methylimidazolium tetrafluorobrate ([C4MIm][BF4]) was the best medium for the reaction because it produced the highest substrate conversion. In [C4MIm][BF4], the optimal ultrasonic power, water activity, and reaction temperature were 120 W, 0.33, and 50 °C, respectively. The acylation of cordycepin in [C4MIm][BF4] proved to be regioselective under both conditions: the C5'-OH was acylated. Novozym 435 exhibited a much higher operational stability in [C4MIm][BF4], and 58.0% of its original activity was maintained after ten reuse cycles under ultrasonic irradiation. Compared with the cordycepin, the rate of adenosine deaminase-catalyzed deamination was greatly reduced when the 5'-OH was substituted by acetyl group. These results demonstrated that the combined application of ultrasonic irradiation and IL as a medium was an efficient approach for the enzymatic modification of cordycepin.
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Affiliation(s)
- Dan-Ni Zhang
- College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, PR China
| | - Xiao-Yu Guo
- College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, PR China
| | - Qiu-Huizi Yang
- College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, PR China
| | - Zhi-Gang Chen
- College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, PR China.
| | - Li-Jia Tao
- College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, PR China
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Yang H, Shi D, Ji SF, Zhang DN, Liu XF. Nanosized Pd assembled on superparamagnetic core–shell microspheres: Synthesis, characterization and recyclable catalytic properties for the Heck reaction. CHINESE CHEM LETT 2014. [DOI: 10.1016/j.cclet.2014.05.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [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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Yang H, Ji S, Liu X, Zhang D, Shi D. Magnetically recyclable Pd/γ-AlOOH@Fe3O4 catalysts and their catalytic performance for the Heck coupling reaction. Sci China Chem 2014. [DOI: 10.1007/s11426-014-5072-4] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Abstract
BACKGROUND Interleukin-33 (IL-33) has recently been implicated in tumor immunity. The aim of this study was to explore the clinical role of serum IL-33 in patients with non-small-cell lung cancer (NSCLC). METHODS Sera collected from 250 healthy volunteers (HV), 256 patients with benign lung diseases (BLD) and 262 NSCLC cases were subjected to IL-33 ELISA and relationships between serum IL-33 and clinical characteristics were evaluated. RESULTS Circulating IL-33 levels were higher in the NSCLC group in comparison with the HV and BLD groups (p<0.001). Using a cut-off level 68 pg/ml (95% specificity in the HV group), IL-33 showed a good diagnostic performance for NSCLC. Multivariate survival analysis indicated that serum IL-33 was an independent prognostic factor in the entire NSCLC group [hazards ratio (HR) = 0.64 for low versus high IL-33 levels, 95% confidence interval (CI) 0.50-0.82; p<0.001] and in 165 selected patients with locally advanced or metastatic disease receiving chemoradiotherapy or chemotherapy (HR 0.70, 95% CI 0.52-0.94; p=0.013). CONCLUSIONS IL-33 is a promising potential diagnostic and prognostic marker in NSCLC, independent of the therapeutic intervention.
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Affiliation(s)
- Liang-An Hu
- Department of Respiratory Diseases, First Affiliated Hospital of Chongqing Medical University, Chongqing, China.
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Chen ZG, Zhang DN, Cao L, Han YB. Highly efficient and regioselective acylation of pharmacologically interesting cordycepin catalyzed by lipase in the eco-friendly solvent 2-methyltetrahydrofuran. Bioresour Technol 2013; 133:82-86. [PMID: 23425581 DOI: 10.1016/j.biortech.2013.01.117] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2012] [Revised: 01/21/2013] [Accepted: 01/21/2013] [Indexed: 06/01/2023]
Abstract
A total of nine lipases and three proteases were tested for enzymatic regioselective acylation(s) of cordycepin with vinyl acetate in organic media. The highest conversion with better initial reaction rate was achieved with immobilized Candida antarctica lipase B (Novozym 435). An eco-friendly solvent 2-methyltetrahydrofuran (MeTHF) was thought to be the most suitable reaction medium. Novozym 435 was found to be a useful biocatalyst for the 25-g scale syntheses of cordycepin acetate (96.2% isolated yield), and the biocatalyst displayed excellent regioselectivity and high operational stability during the transformation. The 5'-substituted cordycepin derivative was the sole detectable product from each acylation reaction. Novozym 435 could be recycled for the synthesis of cordycepin derivative on a 25-g scale and 63% of its original activity was maintained after being reused for 7 batches. MeTHF could be considered as an eco-friendly solvent for the large scale use in biotransformation.
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Affiliation(s)
- Zhi-Gang Chen
- College of Food Science & Technology, Nanjing Agricultural University, Nanjing 210095, PR China.
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Romero LI, Zhang DN, Cooke JP, Ho HK, Avalos E, Herrera R, Herron GS. Differential expression of nitric oxide by dermal microvascular endothelial cells from patients with scleroderma. Vasc Med 2001; 5:147-58. [PMID: 11104297 DOI: 10.1177/1358836x0000500304] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.5] [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: 11/16/2022]
Abstract
Vascular abnormalities in scleroderma are fundamental to the pathogenesis of this disease. The objective of this study was to characterize dermal microvascular endothelial cells (DMEC) isolated from scleroderma patients with respect to growth and expression of the constitutive form of endothelial nitric oxide synthase (eNOS). DMEC from patients with both systemic sclerosis (SSc) and localized scleroderma (Loc Scl) contained small intact microvascular structures in contrast to single cell isolations obtained from control skin. Immunoaffinity selection on anti-PECAM-1 beads yielded pure populations of DMEC expressing normal markers. While the morphology and initial growth of SSc DMEC closely paralleled control cells, the growth of SSc DMEC decreased with time in culture (doubling time of 3 days vs. 5 days). Expression of ecNOS mRNA was reduced in both Loc Scl and SSc as shown by semi-quantitative RT-PCR (p < 0.001). Western blots showed variable but generally lower ecNOS protein levels and decreased levels of nitrogen oxides in media were found from both SSc and Loc Scl relative to control cells. The results indicate an intrinsic defect in the mechanism of nitric oxide production in DMEC isolated from scleroderma patients and suggest its possible involvement in the pathophysiology of scleroderma.
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MESH Headings
- Adult
- Aged
- Cell Division
- Cells, Cultured
- Child
- Endothelium, Vascular/enzymology
- Endothelium, Vascular/pathology
- Female
- Gene Expression Regulation, Enzymologic
- Humans
- Kinetics
- Male
- Microcirculation/pathology
- Microcirculation/physiopathology
- Middle Aged
- Nitric Oxide/metabolism
- Nitric Oxide Synthase/analysis
- Nitric Oxide Synthase/genetics
- Nitric Oxide Synthase Type III
- Platelet Endothelial Cell Adhesion Molecule-1/physiology
- RNA, Messenger/genetics
- Reverse Transcriptase Polymerase Chain Reaction
- Scleroderma, Localized/enzymology
- Scleroderma, Localized/pathology
- Scleroderma, Localized/physiopathology
- Scleroderma, Systemic/enzymology
- Scleroderma, Systemic/pathology
- Scleroderma, Systemic/physiopathology
- Skin/blood supply
- Transcription, Genetic
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Affiliation(s)
- L I Romero
- Department of Dermatology, Stanford University School of Medicine, CA, USA
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Leung DY, Zhang DN. Characteristics of urban ozone level in Hong Kong. J Environ Sci (China) 2001; 13:1-7. [PMID: 11590708] [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: 05/23/2023]
Abstract
The long term trend of ozone level in Hong Kong has been investigated. One of the characteristics of ozone level in Hong Kong is the existence of autumn maximum and summer minimum. Observations of the diurnal variation of ozone level have been made in different area categories. There are early morning peak and afternoon peak occurred in the diurnal variation, which are different from some metropolitans where only an afternoon peak is observed. A negative correlation coefficient was found between monthly ozone level with nitric oxide level. On the contrary, there is a positive correlation between ozone and nitrogen dioxide. The positive correlation coefficient between nitric oxide and nitrogen dioxide shows that the total amount of nitric oxide emitted from a series of moving and fixed sources greatly exceeded the stoichiometric amount of ozone formed from chemical reactions of precursors and long distance transportation.
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Affiliation(s)
- D Y Leung
- Department of Mechanical Engineering, University of Hong Kong, Pokfulam Road, Hong Kong, China.
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12
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Zhang DN, Zhou GY, Zhao ZM. [Treatment of oral leukoplakia: Comparison of the results beteen cryosurgery and laser surgery]. Shanghai Kou Qiang Yi Xue 1999; 8:118-9. [PMID: 15048293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
Affiliation(s)
- D N Zhang
- Department of Dentistry, Material and Children Hygiene Clinic of Pudong New District. Shangahi 201200, China
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Chan VT, Zhang DN, Nagaravapu U, Hultquist K, Romero LI, Herron GS. Membrane-type matrix metalloproteinases in human dermal microvascular endothelial cells: expression and morphogenetic correlation. J Invest Dermatol 1998; 111:1153-9. [PMID: 9856832 DOI: 10.1046/j.1523-1747.1998.00416.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.2] [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: 12/12/2022]
Abstract
Membrane-type matrix metalloproteinases (MT-MMP) activate the zymogen form of MMP-2/Gelatinase A on cell surfaces and are expressed in invasive tumors. We sought to identify and characterize MT-MMP in a non-malignant cell type that undergoes a physiologic and reversible invasive phenotype during angiogenesis. Human dermal microvascular endothelial cells (HDMEC) were isolated from neonatal tissue and purified by anti-CD31 (PECAM) affinity beads. MT-MMP-1 and -3 transcripts were amplified by reverse transcriptase-polymerase chain reaction and northern blots showed a single 4.5 kB mRNA for MT-MMP-1 that was modulated by angiogenic factors and phorbol ester. Immunoblotting of reduced cellular extracts with different MT-MMP-1 antibodies showed the presence of the 63-65 kDa and 57-60 kDa forms, as well as additional forms at lower molecular weights. HDMEC membranes extracted with Triton X114 were incubated with gelatin-sepharose purified MMP-2 and MMP-9 to show activation of proenzymes. Pre-incubation of HDMEC with anti-MT-MMP-1 antibodies decreased proMMP-2 conversion activity only. The movement of HDMEC and the formation of tubule-like structures in three-dimensional collagen gels was markedly delayed by preincubation with the same anti-MT-MMP-1 antibodies. These results demonstrate the presence of MT-MMP in cutaneous microvascular cells in vitro. Modulation of these cell surface proteinases by angiogenic factors, demonstration of multiple processed forms, and specific attenuation of HDMEC morphogenetic patterns in three-dimensional collagen gels implicate their potential roles in the formation of new blood vessels in the skin.
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Affiliation(s)
- V T Chan
- Department of Dermatology, Stanford University School of Medicine, California 94305, USA
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Abstract
To determine the role of the pleiotropic cytokine interleukin-1 (IL-1) on the activation of endothelial cells during inflammation and angiogenesis, pure populations of human dermal microvascular endothelial cells (HDMEC) were obtained by immunoaffinity purification using Ulex europaeus agglutinin-1 and platelet endothelial cell adhesion molecule-1 (PECAM-1) antibody. Exposure of HDMEC to IL-1beta induced morphologic and physiologic changes characterized by 1) phenotypic modulation of endothelial cells from epithelioid to spindle-shaped cells accompanied by reorganization of vimentin filaments; 2) gradual decrease to a complete absence of the endothelial cell markers von Willebrand factor (vWf) and PECAM-1; and 3) increased capability to form tubule-like structures when overlaid with collagen gels. The IL-1 effect on cell morphology, growth, and decrease of endothelial cell antigens was potentiated by basic fibroblast growth factor (bFGF). Similar results were observed in mitotically arrested gamma-irradiated cells demonstrating that the spindle-shaped cells observed after IL-1 stimulation were derived from epithelioid endothelial cells and that DNA synthesis was not required to effect these changes. Immunostaining with an antibody specific for human fibroblasts was negative and further confirmed the endothelial cell origin of the spindle-shaped cells. These data demonstrate that IL-1 can induce phenotypic changes in HDMEC from epithelioid to spindle-shaped, mesenchymal-like cells, that these cells are more susceptible to stimulation by bFGF, and that they lose biochemical and functional properties characteristic of epithelioid HDMEC.
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Affiliation(s)
- L I Romero
- Department of Dermatology, Stanford University School of Medicine, California 94305-5486, USA
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Osbakken M, Douglas PS, Ivanics T, Zhang DN, Van Winkle T. Creatinine kinase kinetics studied by phosphorus-31 nuclear magnetic resonance in a canine model of chronic hypertension-induced cardiac hypertrophy. J Am Coll Cardiol 1992; 19:223-8. [PMID: 1530854 DOI: 10.1016/0735-1097(92)90076-y] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
To determine whether cardiac hypertrophy secondary to chronic renovascular hypertension is associated with altered in vivo myocardial metabolism, phosphorus-31 nuclear magnetic resonance saturation transfer techniques were used to study creatine kinase (CK) kinetics in six chronically hypertensive dogs with moderate cardiac hypertrophy and eight control dogs. The forward rate constant of CK and the flux of phosphocreatine to adenosine triphosphate were determined in both groups of dogs before and during norepinephrine administration (1 microgram/kg per min), used to increase heart rate x systolic blood pressure (rate-pressure product), cardiac output and oxygen consumption. Baseline and norepinephrine-induced changes in rate-pressure product, cardiac output and oxygen consumption were similar in both groups of dogs, as were baseline forward rate constant and flux of phosphocreatine to adenosine triphosphate. However, the norepinephrine-induced changes in forward rate constant and flux were significantly less in hypertensive than in control dogs (p less than 0.05) even though changes in hemodynamic and functional variables were similar in both groups. These data demonstrate that moderate myocardial hypertrophy is associated with altered CK kinetics, which do not appear to affect the heart's ability for global mechanical recruitment at this stage in the hypertensive process. It is possible that the changes in myocardial enzyme kinetics may contribute to diastolic dysfunction previously reported in this model and may be a precursor for ultimate development of heart failure if hypertension is maintained for prolonged periods.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- M Osbakken
- Department of Medicine (Cardiology), School of Medicine, University of Pennsylvania, Philadelphia 19104
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16
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Osbakken M, Zhang DN, Nelson D, Erecińska M. Effect of cyclocreatine feeding on levels of amino acids in rat hearts before and after an ischemic episode. Am J Physiol 1991; 261:H1919-26. [PMID: 1684269 DOI: 10.1152/ajpheart.1991.261.6.h1919] [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] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Feeding Sprague-Dawley rats for 3 wk a diet containing 1% by weight of cyclocreatine increased the reservoir of the high-energy phosphate compounds but also caused alterations in the levels of the two key amino acids, aspartate and glutamate. Both were decreased by approximately 50% in the presence of an unaltered content of glutamine. In vitro exposure of these hearts to sequential perfusion, global ischemia, and reperfusion in the absence of added amino acids resulted in changes in aspartate, glutamate, and glutamine that were different from those in hearts from control rats. In the cyclocreatine-fed group, aspartate concentration ([aspartate]) and [glutamate] fell after global ischemia, whereas [glutamine] was unaltered. [Glutamine] decreased, however, in the reperfusion period. In control hearts, the predominant effect was a steady decline in glutamine, which was accompanied by either less than 10% (after global ischemia) or 30-50% fall (after reperfusion) in [aspartate] and [glutamate]. The concentration of tissue Pi was smaller in hearts from cyclocreatine-fed rats and appeared to increase more slowly during ischemia. In the presence of rotenone and aminooxyacetate, heart homogenates catalyzed production of glutamate from glutamine, which was markedly stimulated by Pi and inhibited by H+. It is postulated that 1) phosphate-activated glutaminase is an important enzyme that determines cardiac [glutamate], 2) lower [phosphate] in hearts from rats fed cyclocreatine is responsible for the apparently lesser activity of glutaminase, 3) breakdown of the high-energy phosphate compounds and consequent rise in Pi activates glutaminase, and 4) slow breakdown of glutamine during global ischemia is a result of inhibition of glutaminase by H+.
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Affiliation(s)
- M Osbakken
- Department of Medicine (Cardiology), University of Pennsylvania School of Medicine, Philadelphia 19104
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17
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Huang DJ, Zhang DN, Yin QX. [Factors affecting parameters of left ventricular diastolic function derived from Doppler echocardiography]. Zhonghua Nei Ke Za Zhi 1990; 29:210-2, 252-3. [PMID: 2226050] [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: 12/30/2022]
Abstract
According to the data from left ventricular catheterization as well as M-mode and two-dimensional echocardiography in 36 patients, the influence of left ventricular diameter, systolic function, systolic and diastolic filling pressures on the parameters of left ventricular diastolic function derived from Doppler echocardiography was analysed. The results indicate: (1) the left ventricular end diastolic pressure, rapid filling wave pressure and the ratio of the both significantly affect the Doppler diastolic function parameters; (2) the decrease of the ratio of early-to-late diastolic mitral flow velocities (E/A) is only a manifestation of early stage of left ventricular diastolic dysfunction and the E/A ratio returns to normal (false improving) at advanced stage of left ventricular diastolic dysfunction.
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Affiliation(s)
- D J Huang
- Department of Internal Medicine, First University Hospital, West China University of Medical Sciences, Chengdu
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18
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Zhang DN. Treatment of chronic renal failure with "serial recipes for renal failure": a report of 64 cases. J TRADIT CHIN MED 1989; 9:159-62. [PMID: 2615442] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The "Serial Recipes for Renal Failure" (SRRF), are 11 recipes formulated in accordance with the morbid mechanisms of deficiency, stagnation, dampness and reverse in chronic renal failure (CRF), for the purposes of replenishing deficiency, and activating blood stagnation as an etiological approach and eliminating dampness and suppressing reverse flow as an symptomatic approach. In the treatment of 64 cases of CRF, the total effective rate of SRRF was 84.4%, and the markedly effective rate 51.6%. The author holds that blood stagnation is the main point in the pathogenic mechanism and recommends comprehensive therapeutic measures.
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Zhang DN, Yin QX, Li XR, Li H, Zhang MS, Wang GG. [Cost-effectiveness analysis of two-dimensional/Doppler echocardiography, cardiac catheterization and angiography in the diagnosis of congenital heart disease]. Hua Xi Yi Ke Da Xue Xue Bao 1989; 20:186-9. [PMID: 2512246] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
To compare the costs and effectivenesses of 2-dimensional/Doppler echocardiography (2D/DE), cardiac catheterization (CC) and angiography (CA) in the evaluation of cardiac anatomy in patients with congenital heart disease, these three kinds of examinations were performed in 100 patients before operation. The 100 patients had 120 separate cardiovascular abnormalities, of which 100 (83.3%) were prospectively identified by 2D/DE. The sensitivity and specificity of 2D/DE were: ASD, 87.9% and 100%; VSD, 97.9% and 96.1%; PDA, 86.7% and 98.2%, Tetralogy of Fallot, 6 of 6 patients; the overall sensitivity and specificity of the less common defects, 31.6% and 95.8%. Ninety-seven (80.8%) were prospectively identified by catheterization. The sensitivity and specificity of catheterization were: ASD, 87.9% and 100.0%; VSD, 80.9% and 94.6%; PDA 93.3% and 96.6%; Tetralogy of Fallot, 6 of 6 patients, the less common defects, 52.6% and 95.5%. Forty-five (81.8%) were prospectively identified by angiography in 55 patients. The sensitivity and specificity of angiography: ASD, 5 of 7 patients, VSD, 88.0% and 94.3%; PDA, 2 of 2 patients; Tetralogy of Fallot, 5 of 5 patients; the less common defects, 68.8% and 100.0%. The economic evaluations were performed. The costs of the depreciation (including equipments and houses), hospital bed, water and electricity, management and staffs' wage were: 2D/DE, RMB 46.09 per patient; catheterization, RMB 314.17 per patient; angiography, RMB 314.17. The ratios of cost to outcome (cost per correct diagnosis) of 2D/DE, CC and CA were: 55.33, 388.82 and 384.07 respectively.(ABSTRACT TRUNCATED AT 250 WORDS)
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Zhang DN, Li XR, Yin QX. [Normal 2-dimensional echocardiographic measurements in 100 adults]. Hua Xi Yi Ke Da Xue Xue Bao 1987; 18:361-4. [PMID: 3449426] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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Zhu Z, Zhang DN. [Experimental study of low-energy intraventricular defibrillation (author's transl)]. Zhonghua Xin Xue Guan Bing Za Zhi 1981; 9:140-3. [PMID: 7318667] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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