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Yan ZZ, Wang YX, Zhang TL, Xun JN, Ma YC, Ji C, Gao J, Xiao SC. [Properties of gelatin-polyethylene glycol hydrogel loaded with silver nanoparticle Chlorella and its effects on healing of infected full-thickness skin defect wounds in mice]. Zhonghua Shao Shang Yu Chuang Mian Xiu Fu Za Zhi 2024; 40:33-42. [PMID: 38296235 DOI: 10.3760/cma.j.cn501225-20231020-00126] [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: 02/08/2024]
Abstract
Objective: To explore the properties of gelatin-polyethylene glycol hydrogel loaded with silver nanoparticle (AgNP) Chlorella (hereinafter referred to as the composite hydrogel) and its effects on healing of infected full-thickness skin defect wounds in mice. Methods: The research was an experimental research. The simple gelatin-polyethylene glycol hydrogel (hereinafter referred to as the simple hydrogel) and the composite hydrogel were prepared, and the appearance and injectability of the two hydrogels were observed at 55 and 37 ℃, and under the irradiation of 808 nm near-infrared light, respectively. An electronic universal testing machine was employed to assess the tensile and compressive stress-strain properties of both types of hydrogels at room temperature. Additionally, the cyclic compressive stress-strain properties of the composite hydrogel were examined at 80% of the maximum compressive stress. Staphylococcus aureus or Escherichia coli solution was added to phosphate buffer solution (PBS), simple hydrogel, and composite hydrogel, respectively. The part of composite hydrogel containing Staphylococcus aureus or Escherichia coli solution was irradiated with near-infrared light for 5 minutes. After each sample was incubated for 6 h, the dilution plating method was used to detect and calculate the mortality rates of the two bacteria at 24 h of culture (n=5). The discarded foreskin tissue was taken from a 6-year-old healthy boy admitted to the Department of Urology of the First Affiliated Hospital of Naval Medical University for circumcision. Primary human fibroblasts (HFbs) were isolated using the enzyme extraction method, routinely cultured to the 3rd to 6th passages for subsequent cellular experiments. Composite hydrogel extracts with final mass concentrations of 100.0, 50.0, 25.0, 12.5, and 0 mg/mL were respectively prepared and used to culture HFbs, and the cell proliferation after 24 h of culture was detected using a cell counting kit 8 (n=3). A total of twenty 6-8 weeks old C57BL/6J female mice were utilized, and a full-thickness skin defect was surgically created on the back of each mouse. The wounds were infected with Staphylococcus aureus solution. The infected mice were divided into blank control group, simple hydrogel group, composite hydrogel group, and combined treatment group according to the random number table, and the wounds were treated with PBS, simple hydrogel, composite hydrogel, and composite hydrogel+light irradiation (under the irradiation of 808 nm near-infrared light for 5 min), respectively, with 5 mice in each group. On post injury day (PID) 0 (immediately after the first wound treatment), 3, 7, and 14, an overall assessment of wound exudation and healing were conducted, and the wound healing rates on PID 7 and 14 were calculated (n=5). On PID 14, hematoxylin-eosin staining was performed to observe histopathological changes in the mouse wound. Results: Both simple hydrogel and composite hydrogel were in a solution state at 55 ℃ and transition to a gel state when cooling to 37 ℃. After the two hydrogels were irradiated by near-infrared light, only the composite hydrogel reheated up and returned to the solution state again with injectability. The maximum tensile stress of the composite hydrogel was up to 301.42 kPa, with a corresponding strain of 87.19%; the maximum compressive stress was up to 413.79 kPa, with a corresponding strain of 91.67%, which was similar to the tensile and compressive properties of the simple hydrogel. After 10 compression cycles, the maximum compressive stress of the composite hydrogel still reached 84.1% of the first compressive stress. After 24 h of culture, the mortality rate of Staphylococcus aureus treated with simple hydrogel was significantly higher than that treated with PBS (P<0.05); the mortality rates of Escherichia coli and Staphylococcus aureus treated with composite hydrogel alone were significantly higher than those treated with simple hydrogel (P<0.05); the mortality rates of Escherichia coli and Staphylococcus aureus treated with composite hydrogel+light irradiation were significantly higher than those treated with composite hydrogel alone (P<0.05). After 24 h of culture, compared with that cultured in composite hydrogel immersion solution with final mass concentration of 0 mg/mL, the proliferation activity of HFbs cultured in composite hydrogel immersion solution with final mass concentrations of 25.0 and 50.0 mg/mL was significantly enhanced (P<0.05), while the proliferation activity of HFbs cultured in composite hydrogel immersion solution with final mass concentration of 100 mg/mL was significantly decreased (P<0.05). On PID 0 and 3, more purulent secretions were seen in the wounds of mice in blank control group and simple hydrogel group, while only a small amount of exudate was observed in the wounds of mice in composite hydrogel group, and no obvious infection was observed in the wounds of mice in combined treatment group. On PID 7 and 14, the wound healing rates of mice in simple hydrogel group were significantly higher than those in blank control group (P<0.05); the wound healing rates of mice in composite hydrogel group were significantly higher than those in simple hydrogel group (P<0.05); the wound healing rates in combined treatment group were significantly higher than those in composite hydrogel group (P<0.05). On PID 14, the wounds of mice in blank control group exhibited a high infiltration of inflammatory cells with no new epithelial layer observed; the wounds of mice in simple hydrogel group displayed a short length of newly formed epithelium with a small amount of inflammatory cells; the wounds of mice in composite hydrogel group exhibited continuous formation of new epithelium and a large amount of immature granulation tissue; the wounds of mice in combined treatment group showed continuous epithelialization with less immature granulation tissue. Conclusions: The prepared composite hydrogel exhibits excellent thermosensitivity, photothermal properties, and injectability, as well as excellent mechanical properties, antibacterial properties, and biocompatibility, and can promote the healing of infected full-thickness skin defect wounds in mice.
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Affiliation(s)
- Z Z Yan
- Department of Burn Surgery, the First Affiliated Hospital of Naval Medical University, Shanghai 200433, China
| | - Y X Wang
- Department of Burn Surgery, the First Affiliated Hospital of Naval Medical University, Shanghai 200433, China
| | - T L Zhang
- Clinical Research Center, the First Affiliated Hospital of Naval Medical University, Shanghai 200433, China
| | - J N Xun
- Department of Burn Surgery, the First Affiliated Hospital of Naval Medical University, Shanghai 200433, China
| | - Y C Ma
- Department of Burn Surgery, the First Affiliated Hospital of Naval Medical University, Shanghai 200433, China
| | - C Ji
- Department of Burn Surgery, the First Affiliated Hospital of Naval Medical University, Shanghai 200433, China
| | - J Gao
- Clinical Research Center, the First Affiliated Hospital of Naval Medical University, Shanghai 200433, China
| | - S C Xiao
- Department of Burn Surgery, the First Affiliated Hospital of Naval Medical University, Shanghai 200433, China
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Xia CM, Zhu M, Zhu LF, Ji PZ, Wu PF, Yang YL, Liu B, Ma YC. [Research progress in the regulation of tumor cell PD-L1 expression by N6-methyladenosine modification]. Zhonghua Bing Li Xue Za Zhi 2023; 52:976-980. [PMID: 37670637 DOI: 10.3760/cma.j.cn112151-20221201-01012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 09/07/2023]
Affiliation(s)
- C M Xia
- Department of Pathology, 940th Hospital of the Chinese People's Liberation Army Joint Logistic Support Force, Lanzhou 730000, China
| | - M Zhu
- Department of Pathology, Gansu University of Chinese Medicine, Lanzhou 730000, China
| | - L F Zhu
- School of Clinical Medicine, Ningxia Medical University, Yinchuan 750004, China
| | - P Z Ji
- Department of Pathology, 940th Hospital of the Chinese People's Liberation Army Joint Logistic Support Force, Lanzhou 730000, China
| | - P F Wu
- Department of Pathology, Gansu University of Chinese Medicine, Lanzhou 730000, China
| | - Y L Yang
- Department of Pathology, 940th Hospital of the Chinese People's Liberation Army Joint Logistic Support Force, Lanzhou 730000, China
| | - B Liu
- Department of Pathology, 940th Hospital of the Chinese People's Liberation Army Joint Logistic Support Force, Lanzhou 730000, China
| | - Y C Ma
- Department of Pathology, 940th Hospital of the Chinese People's Liberation Army Joint Logistic Support Force, Lanzhou 730000, China
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Ma YC, Huang P, Wang XL, Liu GQ. Multi-omics analysis unravels positive effect of rotenone on the cordycepin biosynthesis in submerged fermentation of Cordyceps militaris. Bioresour Technol 2023; 373:128705. [PMID: 36746212 DOI: 10.1016/j.biortech.2023.128705] [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] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Revised: 02/01/2023] [Accepted: 02/02/2023] [Indexed: 06/18/2023]
Abstract
Cordycepin is the key pharmacologically active compound of Cordyceps militaris, and various fermentation strategies have been developed to increase cordycepin production. This study aimed to investigate the effect of rotenone on cordycepin biosynthesis in submerged fermentation of C. militaris, and also to explore its possible induction mechanisms via multi-omics analysis. Adding 5 mg/L rotenone significantly increased the cordycepin production by 316.09 %, along with mycelial growth inhibition and cell wall destruction. Moreover, transcriptomic analysis and metabolomic analysis revealed the accumulation of cordycepin was promoted by alterations in energy metabolism and amino acid metabolism pathways. Finally, the integration analysis of the two omics confirmed rotenone altered the nucleotide metabolism pathway toward adenosine and up-regulated the cordycepin synthesis genes (cns1-3) to convert adenosine to cordycepin. This work reports, for the first time, rotenone could act as an effective inducer of cordycepin synthesis.
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Affiliation(s)
- You-Chu Ma
- International Cooperation Base of Science and Technology Innovation on Forest Resource Biotechnology of Hunan Province, Central South University of Forestry & Technology, Changsha, Hunan 410004, China; Hunan Provincial Key Laboratory of Forestry Biotechnology, Central South University of Forestry & Technology, Changsha, Hunan 410004, China; Microbial Variety Creation Center, Hunan Provincial Laboratory of Yuelushan Seed Industry, Changsha 410004, China
| | - Ping Huang
- International Cooperation Base of Science and Technology Innovation on Forest Resource Biotechnology of Hunan Province, Central South University of Forestry & Technology, Changsha, Hunan 410004, China; Hunan Provincial Key Laboratory of Forestry Biotechnology, Central South University of Forestry & Technology, Changsha, Hunan 410004, China
| | - Xiao-Ling Wang
- International Cooperation Base of Science and Technology Innovation on Forest Resource Biotechnology of Hunan Province, Central South University of Forestry & Technology, Changsha, Hunan 410004, China; Hunan Provincial Key Laboratory of Forestry Biotechnology, Central South University of Forestry & Technology, Changsha, Hunan 410004, China; Microbial Variety Creation Center, Hunan Provincial Laboratory of Yuelushan Seed Industry, Changsha 410004, China
| | - Gao-Qiang Liu
- International Cooperation Base of Science and Technology Innovation on Forest Resource Biotechnology of Hunan Province, Central South University of Forestry & Technology, Changsha, Hunan 410004, China; Hunan Provincial Key Laboratory of Forestry Biotechnology, Central South University of Forestry & Technology, Changsha, Hunan 410004, China; Microbial Variety Creation Center, Hunan Provincial Laboratory of Yuelushan Seed Industry, Changsha 410004, China.
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Zhang ZJ, Yin YY, Cui Y, Zhang YX, Liu BY, Ma YC, Liu YN, Liu GQ. Chitinase Is Involved in the Fruiting Body Development of Medicinal Fungus Cordyceps militaris. Life (Basel) 2023; 13:life13030764. [PMID: 36983919 PMCID: PMC10051443 DOI: 10.3390/life13030764] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2023] [Revised: 02/22/2023] [Accepted: 03/10/2023] [Indexed: 03/14/2023] Open
Abstract
Cordyceps militaris is a famous traditional edible and medicinal fungus in Asia, and its fruiting body has rich medicinal value. The molecular mechanism of fruiting body development is still not well understood in C. militaris. In this study, phylogenetically analysis and protein domains prediction of the 14 putative chitinases were performed. The transcription level and enzyme activity of chitinase were significant increased during fruiting body development of C. militaris. Then, two chitinase genes (Chi1 and Chi4) were selected to construct gene silencing strain by RNA interference. When Chi1 and Chi4 genes were knockdown, the differentiation of the primordium was blocked, and the number of fruiting body was significantly decreased approximately by 50% compared to wild-type (WT) strain. The length of the single mature fruiting body was shortened by 27% and 38% in Chi1- and Chi4-silenced strains, respectively. In addition, the chitin content and cell wall thickness were significantly increased in Chi1- and Chi4-silenced strains. These results provide new insights into the biological functions of chitinase in fruiting body development of C. militaris.
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Affiliation(s)
- Zi-Juan Zhang
- Hunan Provincial Key Laboratory of Forestry Biotechnology, Central South University of Forestry & Technology, Changsha 410004, China
- International Cooperation Base of Science and Technology Innovation on Forest Resource Biotechnology of Hunan Province, Central South University of Forestry & Technology, Changsha 410004, China
- Microbial Variety Creation Center, Yuelushan Laboratory of Seed Industry, Changsha 410004, China
| | - Yuan-Yuan Yin
- Hunan Provincial Key Laboratory of Forestry Biotechnology, Central South University of Forestry & Technology, Changsha 410004, China
- International Cooperation Base of Science and Technology Innovation on Forest Resource Biotechnology of Hunan Province, Central South University of Forestry & Technology, Changsha 410004, China
- Microbial Variety Creation Center, Yuelushan Laboratory of Seed Industry, Changsha 410004, China
| | - Yao Cui
- Hunan Provincial Key Laboratory of Forestry Biotechnology, Central South University of Forestry & Technology, Changsha 410004, China
- International Cooperation Base of Science and Technology Innovation on Forest Resource Biotechnology of Hunan Province, Central South University of Forestry & Technology, Changsha 410004, China
- Microbial Variety Creation Center, Yuelushan Laboratory of Seed Industry, Changsha 410004, China
| | - Yue-Xuan Zhang
- Hunan Provincial Key Laboratory of Forestry Biotechnology, Central South University of Forestry & Technology, Changsha 410004, China
- International Cooperation Base of Science and Technology Innovation on Forest Resource Biotechnology of Hunan Province, Central South University of Forestry & Technology, Changsha 410004, China
- Microbial Variety Creation Center, Yuelushan Laboratory of Seed Industry, Changsha 410004, China
| | - Bi-Yang Liu
- Hunan Provincial Key Laboratory of Forestry Biotechnology, Central South University of Forestry & Technology, Changsha 410004, China
- International Cooperation Base of Science and Technology Innovation on Forest Resource Biotechnology of Hunan Province, Central South University of Forestry & Technology, Changsha 410004, China
- Microbial Variety Creation Center, Yuelushan Laboratory of Seed Industry, Changsha 410004, China
| | - You-Chu Ma
- Hunan Provincial Key Laboratory of Forestry Biotechnology, Central South University of Forestry & Technology, Changsha 410004, China
- International Cooperation Base of Science and Technology Innovation on Forest Resource Biotechnology of Hunan Province, Central South University of Forestry & Technology, Changsha 410004, China
- Microbial Variety Creation Center, Yuelushan Laboratory of Seed Industry, Changsha 410004, China
| | - Yong-Nan Liu
- Hunan Provincial Key Laboratory of Forestry Biotechnology, Central South University of Forestry & Technology, Changsha 410004, China
- International Cooperation Base of Science and Technology Innovation on Forest Resource Biotechnology of Hunan Province, Central South University of Forestry & Technology, Changsha 410004, China
- Microbial Variety Creation Center, Yuelushan Laboratory of Seed Industry, Changsha 410004, China
- Correspondence: (Y.-N.L.); (G.-Q.L.); Tel./Fax: +86-731-8562-3490 (Y.N.-L.)
| | - Gao-Qiang Liu
- Hunan Provincial Key Laboratory of Forestry Biotechnology, Central South University of Forestry & Technology, Changsha 410004, China
- International Cooperation Base of Science and Technology Innovation on Forest Resource Biotechnology of Hunan Province, Central South University of Forestry & Technology, Changsha 410004, China
- Microbial Variety Creation Center, Yuelushan Laboratory of Seed Industry, Changsha 410004, China
- Correspondence: (Y.-N.L.); (G.-Q.L.); Tel./Fax: +86-731-8562-3490 (Y.N.-L.)
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Huang P, Luo FJ, Ma YC, Wang SX, Huang J, Qin DD, Xue FF, Liu BY, Wu Q, Wang XL, Liu GQ. Dual antioxidant activity and the related mechanisms of a novel pentapeptide GLP4 from the fermented mycelia of Ganoderma lingzhi. Food Funct 2022; 13:9032-9048. [PMID: 35943028 DOI: 10.1039/d2fo01572b] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Oxidative stress causes chronic inflammation, and mediates various diseases. The discovery of antioxidants from natural sources is important to research. Here we identified a novel antioxidant peptide (GLP4) from Ganoderma lingzhi mycelium and investigated its antioxidant type and potential protective mechanisms. Through free radical scavenging assay, active site shielding validation, superoxide dismutase (SOD) activity assay, and lipid peroxidation assay, we demonstrated that GLP4 was a novel protective agent with both direct and indirect antioxidant activities. GLP4 could directly enter human umbilical vein endothelial cells (HUVECs) as an exogenous substance. Meanwhile, GLP4 promoted the nuclear translocation of nuclear factor erythroid-2-related factor 2 (Nrf2) and activated the Nrf2/antioxidant response element (ARE) signaling pathway, exhibiting antioxidant and anti-apoptotic cytoprotective effects on hydrogen peroxide (H2O2)-induced HUVECs. Pull-down experiments of GLP4 target proteins, bioinformatics analysis and molecular docking further revealed that GLP4 mediated Nrf2 activation through binding to phosphoglycerate mutase 5 (PGAM5). The results suggested that GLP4 is a novel peptide with dual antioxidant activity and has promising potential as a protective agent in preventing oxidative stress-related diseases.
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Affiliation(s)
- Ping Huang
- Hunan Provincial Key Laboratory of Forestry Biotechnology & International Cooperation Base of Science and Technology Innovation on Forest Resource Biotechnology, Central South University of Forestry and Technology, Changsha 410004, China. .,Microbial Variety Creation Center, Yuelushan National Laboratory of Seed Industry, Changsha 410004, China
| | - Fei-Jun Luo
- Laboratory of Molecular Nutrition, National Engineering Research Center for Rice and Byproducts, Central South University of Forestry and Technology, Changsha 410004, China
| | - You-Chu Ma
- Hunan Provincial Key Laboratory of Forestry Biotechnology & International Cooperation Base of Science and Technology Innovation on Forest Resource Biotechnology, Central South University of Forestry and Technology, Changsha 410004, China. .,Microbial Variety Creation Center, Yuelushan National Laboratory of Seed Industry, Changsha 410004, China
| | - Si-Xian Wang
- Hunan Provincial Key Laboratory of Forestry Biotechnology & International Cooperation Base of Science and Technology Innovation on Forest Resource Biotechnology, Central South University of Forestry and Technology, Changsha 410004, China. .,Microbial Variety Creation Center, Yuelushan National Laboratory of Seed Industry, Changsha 410004, China
| | - Jia Huang
- Hunan Provincial Key Laboratory of Forestry Biotechnology & International Cooperation Base of Science and Technology Innovation on Forest Resource Biotechnology, Central South University of Forestry and Technology, Changsha 410004, China. .,Microbial Variety Creation Center, Yuelushan National Laboratory of Seed Industry, Changsha 410004, China
| | - Dan-Dan Qin
- Laboratory of Molecular Nutrition, National Engineering Research Center for Rice and Byproducts, Central South University of Forestry and Technology, Changsha 410004, China
| | - Fei-Fei Xue
- Hunan Provincial Key Laboratory of Forestry Biotechnology & International Cooperation Base of Science and Technology Innovation on Forest Resource Biotechnology, Central South University of Forestry and Technology, Changsha 410004, China. .,Microbial Variety Creation Center, Yuelushan National Laboratory of Seed Industry, Changsha 410004, China
| | - Bi-Yang Liu
- Hunan Provincial Key Laboratory of Forestry Biotechnology & International Cooperation Base of Science and Technology Innovation on Forest Resource Biotechnology, Central South University of Forestry and Technology, Changsha 410004, China. .,Microbial Variety Creation Center, Yuelushan National Laboratory of Seed Industry, Changsha 410004, China
| | - Qiang Wu
- Hunan Provincial Key Laboratory of Forestry Biotechnology & International Cooperation Base of Science and Technology Innovation on Forest Resource Biotechnology, Central South University of Forestry and Technology, Changsha 410004, China. .,Microbial Variety Creation Center, Yuelushan National Laboratory of Seed Industry, Changsha 410004, China
| | - Xiao-Ling Wang
- Hunan Provincial Key Laboratory of Forestry Biotechnology & International Cooperation Base of Science and Technology Innovation on Forest Resource Biotechnology, Central South University of Forestry and Technology, Changsha 410004, China. .,Microbial Variety Creation Center, Yuelushan National Laboratory of Seed Industry, Changsha 410004, China
| | - Gao-Qiang Liu
- Hunan Provincial Key Laboratory of Forestry Biotechnology & International Cooperation Base of Science and Technology Innovation on Forest Resource Biotechnology, Central South University of Forestry and Technology, Changsha 410004, China. .,Microbial Variety Creation Center, Yuelushan National Laboratory of Seed Industry, Changsha 410004, China
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Liu YN, Liu BY, Ma YC, Yang HL, Liu GQ. Analysis of reference genes stability and histidine kinase expression under cold stress in Cordyceps militaris. PLoS One 2020; 15:e0236898. [PMID: 32785280 PMCID: PMC7423124 DOI: 10.1371/journal.pone.0236898] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Accepted: 07/15/2020] [Indexed: 11/17/2022] Open
Abstract
The development of fungal fruiting bodies from a hyphal thallus is inducible under low temperature (cold stress). The molecular mechanism has been subject to surprisingly few studies. Analysis of gene expression level has become an important means to study gene function and its regulation mechanism. But identification of reference genes (RGs) stability under cold stress have not been reported in famous medicinal mushroom-forming fungi Cordyceps militaris. Herein, 12 candidate RGs had been systematically validated under cold stress in C. militaris. Three different algorithms, geNorm, NormFinder and BestKeeper were applied to evaluate the expression stability of the RGs. Our results showed that UBC and UBQ were the most stable RGs for cold treatments in short and long periods, respectively. 2 RGs (UBC and PP2A) and 3 RGs (UBQ, TUB and CYP) were the suitable RGs for cold treatments in short and long periods, respectively. Moreover, target genes, two-component-system histidine kinase genes, were selected to validate the most and least stable RGs under cold treatment, which indicated that use of unstable expressed genes as RGs leads to biased results. Our results provide a good starting point for accurate reverse transcriptase quantitative polymerase chain reaction normalization by using UBC and UBQ in C. militaris under cold stress and better support for understanding the mechanism of response to cold stress and fruiting body formation in C. militaris and other mushroom-forming fungi in future research.
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Affiliation(s)
- Yong-Nan Liu
- Hunan Provincial Key Laboratory for Forestry Biotechnology & International Cooperation Base of Science and Technology Innovation on Forest Resource Biotechnology, Central South University of Forestry and Technology, Changsha, China
| | - Bi-Yang Liu
- Hunan Provincial Key Laboratory for Forestry Biotechnology & International Cooperation Base of Science and Technology Innovation on Forest Resource Biotechnology, Central South University of Forestry and Technology, Changsha, China
| | - You-Chu Ma
- Hunan Provincial Key Laboratory for Forestry Biotechnology & International Cooperation Base of Science and Technology Innovation on Forest Resource Biotechnology, Central South University of Forestry and Technology, Changsha, China
| | - Hai-Long Yang
- College of Environmental & Life Science, Wenzhou University, Wenzhou, China
| | - Gao-Qiang Liu
- Hunan Provincial Key Laboratory for Forestry Biotechnology & International Cooperation Base of Science and Technology Innovation on Forest Resource Biotechnology, Central South University of Forestry and Technology, Changsha, China
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Xu LL, Zhao JH, Qin Y, Peng ZB, Zheng JD, Wang LP, Ding XJ, Feng LZ, Ma YC. [Current situation and related policies on the implementation and promotion of influenza vaccination among health care workers]. Zhonghua Yu Fang Yi Xue Za Zhi 2019; 53:973-977. [PMID: 31607040 DOI: 10.3760/cma.j.issn.0253-9624.2019.10.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Health care workers have higher risk of influenza infection because of their occupational exposure to infected patients. Infection of the health care workers may not only result in the increasing risk of the nosocomial infection and family transmission, but also disrupt the health services due to absence from work. Health care workers were recommended as a priority group of influenza vaccinationin more than 40 countries and regions in the world. In recent years, domestic surveys show that the influenza vaccine coverage among health care workers was low. This paper outlines the current status and related policies of influenza vaccination among health care workers in China and global. Additionally, we analyzed and discussed the proper immunization strategy of influenza vaccine for medical staff in China.
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Affiliation(s)
- L L Xu
- Institute for Infectious Disease Control and Prevention, Qinghai Provincial Center for Disease Control and Prevention, Xining 810007, China
| | - J H Zhao
- Institute for Infectious Disease Control and Prevention, Qinghai Provincial Center for Disease Control and Prevention, Xining 810007, China
| | - Y Qin
- Division of Infectious Disease, Chinese Center for Disease Control and Prevention, Beijing 102206, China
| | - Z B Peng
- Division of Infectious Disease, Chinese Center for Disease Control and Prevention, Beijing 102206, China
| | - J D Zheng
- Division of Infectious Disease, Chinese Center for Disease Control and Prevention, Beijing 102206, China
| | - L P Wang
- Division of Infectious Disease, Chinese Center for Disease Control and Prevention, Beijing 102206, China
| | - X J Ding
- Institute for Infectious Disease Control and Prevention, Qinghai Provincial Center for Disease Control and Prevention, Xining 810007, China
| | - L Z Feng
- Division of Infectious Disease, Chinese Center for Disease Control and Prevention, Beijing 102206, China
| | - Y C Ma
- Institute for Infectious Disease Control and Prevention, Qinghai Provincial Center for Disease Control and Prevention, Xining 810007, China
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Liu YN, Tong T, Zhang RR, Liu LM, Shi ML, Ma YC, Liu GQ. Interdependent nitric oxide and hydrogen peroxide independently regulate the coix seed oil-induced triterpene acid accumulation in Ganoderma lingzhi. Mycologia 2019; 111:529-540. [PMID: 31158070 DOI: 10.1080/00275514.2019.1615816] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Recent progress has been made in adding exogenous vegetable oils in culture media to promote bioactive metabolite production in several medicinal mushrooms, but the mechanism is still unclear. In this study, we found that the vegetable oil coix seed oil (CSO) could induce the biosynthesis of triterpene acids (TAs) and also significantly increase cytoplasmic nitric oxide (NO) and hydrogen peroxide (H2O2) concentrations in the mycelium of Ganoderma lingzhi. The change in TA biosynthesis caused by CSO could be reversed by adding NO scavenger or H2O2 scavenger, and adding NO scavenger or H2O2 scavenger resulted in the reduction of the cytoplasmic H2O2 or NO concentration under CSO treatment, respectively. Moreover, adding NO scavenger or H2O2 scavenger reversed TA biosynthesis, which could be rescued by H2O2 or NO donor, respectively. Taken together, our study indicated that both NO and H2O2 were involved in the regulation of TA biosynthesis, and CSO-activated NO and H2O2 were interdependent but independently regulated the TA biosynthesis under CSO treatment in G. lingzhi.
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Affiliation(s)
- Yong-Nan Liu
- a International Cooperation Base of Science and Technology Innovation on Forest Resource Biotechnology of Hunan Province, Central South University of Forestry & Technology , 498 Southern Shaoshan Road, Changsha 410004 , China.,b Hunan Provincial Key Laboratory of Forestry Biotechnology, Central South University of Forestry & Technology , Changsha 410004 , China
| | - Tian Tong
- a International Cooperation Base of Science and Technology Innovation on Forest Resource Biotechnology of Hunan Province, Central South University of Forestry & Technology , 498 Southern Shaoshan Road, Changsha 410004 , China.,b Hunan Provincial Key Laboratory of Forestry Biotechnology, Central South University of Forestry & Technology , Changsha 410004 , China
| | - Rong-Rong Zhang
- a International Cooperation Base of Science and Technology Innovation on Forest Resource Biotechnology of Hunan Province, Central South University of Forestry & Technology , 498 Southern Shaoshan Road, Changsha 410004 , China.,b Hunan Provincial Key Laboratory of Forestry Biotechnology, Central South University of Forestry & Technology , Changsha 410004 , China
| | - Li-Ming Liu
- c School of Biotechnology, Jiangnan University , Wuxi 214122 , China
| | - Mu-Ling Shi
- a International Cooperation Base of Science and Technology Innovation on Forest Resource Biotechnology of Hunan Province, Central South University of Forestry & Technology , 498 Southern Shaoshan Road, Changsha 410004 , China.,b Hunan Provincial Key Laboratory of Forestry Biotechnology, Central South University of Forestry & Technology , Changsha 410004 , China
| | - You-Chu Ma
- a International Cooperation Base of Science and Technology Innovation on Forest Resource Biotechnology of Hunan Province, Central South University of Forestry & Technology , 498 Southern Shaoshan Road, Changsha 410004 , China.,b Hunan Provincial Key Laboratory of Forestry Biotechnology, Central South University of Forestry & Technology , Changsha 410004 , China
| | - Gao-Qiang Liu
- a International Cooperation Base of Science and Technology Innovation on Forest Resource Biotechnology of Hunan Province, Central South University of Forestry & Technology , 498 Southern Shaoshan Road, Changsha 410004 , China.,b Hunan Provincial Key Laboratory of Forestry Biotechnology, Central South University of Forestry & Technology , Changsha 410004 , China
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Zhu YL, Wang AF, Fan XX, Zhao NM, Ma YC. [DS2, a newly synthetic ent-kaurane diterpenoid analog, inhibits proliferation and migration of human gastric cancer cell]. Zhonghua Zhong Liu Za Zhi 2018; 40:493-498. [PMID: 30060356 DOI: 10.3760/cma.j.issn.0253-3766.2018.07.003] [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
Objective: To investigate the effects and the underlying mechanism of DS2, a newly synthetic analog of natural ent-kaurane diterpenoid, on the proliferation and migration capabilities of human gastric cancer cells. Methods: MTT assay, colony formation assay and flow cytometry were used to measure the effects of DS2 on growth, apoptosis and cell cycle of several human gastric cancer cell lines. The function of DS2 in the migration was further detected by wound healing and transwell assays. The expression of migration related proteins were determined by western blot. Results: DS2 inhibited the growth of MGC-803, SGC-7901 and HGC-27 cells in a dose dependent manner. After treatment of DS2 at a concentration of 6.25 μmol/L for 24 h, the survival rates of MGC-803, SGC-7901 and HGC-27 cells were 53.87±3.05%, 55.91±6.97% and 32.41±2.64%, respectively. However, for the normal gastric epithelial cell GES-1, no obvious growth inhibition was observed. In addition, DS2 caused significant G(2)/M arrest and induced apoptosis in MGC-803 cells. Furthermore, compared with the negative control, the colony formation, wound healing rate as well as the number of migrating cells of MGC-803 were significantly decreased in a dose dependent manner after DS2 treatment. DS2 induced the expression of E-cadherin, whereas β-catenin and N-cadherin levels were downregulated in MGC-803. Conclusion: The new compound DS2 has a strong anti-cancer activity, and this study will help us to design and synthesize better diterpenoids derivatives.
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Affiliation(s)
- Y L Zhu
- Clinical Pharmacology Laboratory, People's Hospital of Zhengzhou University, Zhengzhou 450003, China
| | - A F Wang
- Department of Pharmacy, Fuwai Central China Cardiovascular Hospital, Zhengzhou 451464, China
| | - X X Fan
- Clinical Pharmacology Laboratory, People's Hospital of Zhengzhou University, Zhengzhou 450003, China
| | - N M Zhao
- Clinical Pharmacology Laboratory, People's Hospital of Zhengzhou University, Zhengzhou 450003, China
| | - Y C Ma
- Department of Pharmacy, Fuwai Central China Cardiovascular Hospital, Zhengzhou 451464, China
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10
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Ma YC, Su N, Zhao NM, Li QY, Zhang M, Zhao HW, Liu HM, Qin YH. [Jaridonin, a new diterpenoid from Isodon rubescens, induces cell cycle arrest in gastric cancer cells through activating ataxia telangiectasia mutated kinase]. Zhonghua Zhong Liu Za Zhi 2016; 38:258-62. [PMID: 27087371 DOI: 10.3760/cma.j.issn.0253-3766.2016.04.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
OBJECTIVE To study the effects of Jaridonin, a novel diterpenoid from isodon rubescens, on the cell cycle of human gastric cancer cells and its molecular mechanism of action. METHODS Flow cytometry was used to analyze the cell cycle distribution and expression of ataxia telangiectasia mutated kinase (ATM) after Jaridonin treatment. Western blot was performed to detect the expression of cell cycle-related proteins. RESULTS The results of flow cytometry showed that the percentages of MGC-803 cells in G(2)/M phase at 6 hours after 0, 10, 20 μmol/L Jaridonin-treatment were (10.8±2.2)%, (18.2±2.5)%, (27.3±3.2)%, respectively; those at 12 hours after Jaridonin-treatment were (12.0±1.5)%, (24.1±2.0)% and (39.7±5.2)%, respectively, indicating a G2/M phase arrest of MGC-803 cells was resulted in a time- and dose-dependent manner. The expressions of ATM, Chk1, Chk2, phosphorylated Cdc2 and CDK2 were up-regulated in the MGC-803 cells after Jaridonin treatment, while the levels of Cdc2 and CDK2 were decreased. KU-55933, an inhibitor of ATM, reversed the expression of relevant proteins and G(2)/M phase arrest induced by Jaridonin. CONCLUSIONS Jaridonin can significantly induce G(2)/M arrest in gastric cancer MGC-803 cells. Its mechanism may be related to the activation of ATM and Chk1/2, and inactivation of Cdc2 and CDK2 phosphorylation.
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Affiliation(s)
- Y C Ma
- Laboratory of Clinical Pharmacology, People's Hospital, Zhengzhou University, Zhengzhou 450003, China
| | - N Su
- School of Food Science and Engineering, Henan University of Animal Husbandry and Economy, Zhengzhou 450011, China
| | - N M Zhao
- Laboratory of Clinical Pharmacology, People's Hospital, Zhengzhou University, Zhengzhou 450003, China
| | - Q Y Li
- Laboratory of Clinical Pharmacology, People's Hospital, Zhengzhou University, Zhengzhou 450003, China
| | - M Zhang
- Laboratory of Clinical Pharmacology, People's Hospital, Zhengzhou University, Zhengzhou 450003, China
| | - H W Zhao
- Laboratory of Clinical Pharmacology, People's Hospital, Zhengzhou University, Zhengzhou 450003, China
| | - H M Liu
- School of Pharmaceutical Sciences, New Drug Research& Development Center, Zhengzhou University, Zhengzhou 450001, China
| | - Y H Qin
- Laboratory of Clinical Pharmacology, People's Hospital, Zhengzhou University, Zhengzhou 450003, China
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11
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Abstract
Temperature-dependent resistivities in the ab-plane and c-axis of Tl-based cuprates have been measured. Unlike the ab-plane properties, which are metallic, c-axis transport is semiconductor-like in the normal state for Tl(2)Ba(2)Ca(2)Cu(3)O(x) (Tl-2223) and Tl(2)Ba(2)CaCu(2)O(x) (Tl-2212). In contrast, for Tl(2)Ba(2)CuO(x) (Tl-2201), transport is metal-like in both the in-plane and the c-axis. For multi-layered cuprates, transport properties along the c-axis could be described by a tunnelling model, whereas for single-layered compound Tl-2201 it would be easier for the out-of-plane transport behaviour to be coherent since the there are no insulating Ca layers in its structure. Moreover, combining the studies on Bi-2201, which has an insulating behaviour for the out-of-plane resistivity, we suggest that the Tl-O layers in Tl-based superconductors could be conducting, unlike the weakly correlated Bi-O layers in Bi-based cuprates.
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Affiliation(s)
- Y C Ma
- Tianjin Key Laboratory for Functional Materials and Device Physics, School of Material Science and Engineering, Tianjin University of Technology, Tianjin 300191, People's Republic of China. Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100080, People's Republic of China
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12
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Wang NL, Zheng P, Wu D, Ma YC, Xiang T, Jin RY, Mandrus D. Infrared probe of the electronic structure and charge dynamics of Na0.7CoO2. Phys Rev Lett 2004; 93:237007. [PMID: 15601194 DOI: 10.1103/physrevlett.93.237007] [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] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/24/2003] [Indexed: 05/24/2023]
Abstract
We present measurements of the optical spectra on Na(0.7)CoO(2) single crystals. The optical conductivity shows two broad interband transition peaks at 1.6 eV and 3.1 eV, and a weak midinfrared peak at 0.4 eV. The intraband response of conducting carriers is different from that of a simple Drude metal. A peak at low but finite frequency is observed, which shifts to higher frequencies with increasing temperature, even though the dc resistivity is metallic. The origin of the interband transitions and the low-frequency charge dynamics have been discussed and compared with other experiments.
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Affiliation(s)
- N L Wang
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100080, People's Republic of China
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13
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Khouri IF, Albitar M, Saliba RM, Ippoliti C, Ma YC, Keating MJ, Champlin RE. Low-dose alemtuzumab (Campath®) in myeloablative allogeneic stem cell transplantation for CD52-positive malignancies: decreased incidence of acute graft-versus-host-disease with unique pharmacokinetics. Bone Marrow Transplant 2004; 33:833-7. [PMID: 14755312 DOI: 10.1038/sj.bmt.1704435] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Alemtuzumab is effective in reducing the risk of acute graft-versus-host disease (GVHD) after allogeneic stem cell transplantation (ASCT). Alemtuzumab may also delay immune reconstitution and reduce graft-versus-leukemia effects. The optimal dose has not been established. We investigated engraftment, acute GVHD incidence and severity, and pharmacokinetics of alemtuzumab associated with the use of low-dose alemtuzumab/cyclophosphamide/total body irradiation and ASCT for patients with aggressive CD52-positive hematologic malignancies. In all, 12 patients were treated. Alemtuzumab 10 mg daily on days -7 to -3 was given intravenously. Tacrolimus and methotrexate were used for GVHD prophylaxis. Alemtuzemab was not detected in any of the 36 sequential serum samples tested between days -1 and +21 of transplant. All patients engrafted rapidly; the median time to an absolute neutrophil count >0.5 x 10(9)/l was 14 days (range 11-17 days), and the median time to a platelet count >20 x 10(9)/l was 16 days (range 6-30 days). By 1 month after transplant, nine patients had 100% donor chimerism, while three had mixed donor chimerism. At 3 months, 11 had achieved 100% donor chimerism. No cases of grade III/IV acute GVHD occurred. At a median follow-up interval of 14.7 months (range 4-24), seven patients remained alive, and five remained free of disease.
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Affiliation(s)
- I F Khouri
- Department of Blood and Marrow Transplantation, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
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14
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Chuang CY, Hung JC, Yang CY, Ma YC, Sung FC. Plasma nitrogen oxides levels in taxi drivers and community residents. Bull Environ Contam Toxicol 2003; 70:430-436. [PMID: 12592514 DOI: 10.1007/s00128-003-0004-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Affiliation(s)
- C Y Chuang
- Institute of Environmental Health, National Taiwan University College of Public Health, 1 Jen-Ai Road Section 1, Room 1521, Taipei 100, Taiwan
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15
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Abstract
Src tyrosine kinase is a critical signal transducer that modulates a wide variety of cellular functions. Misregulation of Src leads to cell transformation and cancer. Heterotrimeric guanine-nucleotide-binding proteins (G proteins) are another group of signaling molecules that transduce signals from cell-surface receptors to generate physiological responses. Recently, it was discovered that G alpha s and G alpha i could directly stimulate Src family tyrosine kinase activity. This novel regulation of Src tyrosine kinase by G proteins provides insights into the adenylyl cyclase-independent signaling mechanisms involved in ligand-induced receptor desensitization, internalization and other physiological processes.
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Affiliation(s)
- Y C Ma
- Department of Physiology, Weill Medical College of Cornell University, New York, NY 10021, USA
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16
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Abstract
Heterotrimeric GTP-binding proteins (G proteins) control cellular functions by transducing signals from the outside to the inside of cells. Regulator of G protein signaling (RGS) proteins are key modulators of the amplitude and duration of G protein-mediated signaling through their ability to serve as guanosine triphosphatase-activating proteins (GAPs). We have identified RGS-PX1, a Galpha(s)-specific GAP. The RGS domain of RGS-PX1 specifically interacted with Galpha(s), accelerated its GTP hydrolysis, and attenuated Galpha(s)-mediated signaling. RGS-PX1 also contains a Phox (PX) domain that resembles those in sorting nexin (SNX) proteins. Expression of RGS-PX1 delayed lysosomal degradation of the EGF receptor. Because of its bifunctional role as both a GAP and a SNX, RGS-PX1 may link heterotrimeric G protein signaling and vesicular trafficking.
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Affiliation(s)
- B Zheng
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, CA 92093-0651, USA
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17
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Abstract
Thiodiglycolic acid (TdGA) is the major metabolite of vinyl chloride monomer (VCM) detected in human urine. Although urinary TdGA has been reported to be associated with ambient VCM exposure, the relationship between urinary TdGA and a low level of air VCM is not clear. Questionnaires were administered to 16 polyvinyl chloride manufacturing workers to obtain a detailed history of occupation and lifestyle. For each worker, personal air monitoring for VCM was performed and a time-weighted average for VCM exposure was calculated. The urinary TdGA levels at the end of a work shift, and at the commencement of the next shift, were also assessed for each worker. Urine analysis revealed that TdGA levels at the beginning of the next shift were higher than those at the end of that shift. Workers experiencing a VCM exposure greater than 5 ppm in air revealed a urinary TdGA level significantly greater than those experiencing a VCM exposure of less than 5 ppm (P < 0.05). The best fit of regression for urinary TdGA on air VCM was Y = 1.06 + 0.57X for urine collected at the commencement of the following work shift, where X is the air VCM concentration and Y is the urinary TdGA concentration (r2 = 0.65, P < 0.01). We conclude that the urinary TdGA level is best detected at the commencement of the next shift and that it can be used as an exposure marker for polyvinyl chloride workers when the air VCM level to which they are exposed is greater than 5 ppm.
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Affiliation(s)
- T J Cheng
- Institute of Occupational Medicine and Industrial Hygiene, College of Public Health, National Taiwan University, No. 1 Ren-Ai Rd., Sec. 1, Taipei, Taiwan.
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18
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Affiliation(s)
- Y C Ma
- Department of Pediatrics, Albert Einstein College of Medicine, Yeshiva University, 1410 Pelham Parkway South, Bronx, NY, USA.
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19
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Abstract
Heterotrimeric G proteins transduce signals from cell surface receptors to modulate the activity of cellular effectors. Src, the product of the first characterized proto-oncogene and the first identified protein tyrosine kinase, plays a critical role in the signal transduction of G protein-coupled receptors. However, the mechanism of biochemical regulation of Src by G proteins is not known. Here we demonstrate that Galphas and Galphai, but neither Galphaq, Galpha12 nor Gbetay, directly stimulate the kinase activity of downregulated c-Src. Galphas and Galphai similarly modulate Hck, another member of Src-family tyrosine kinases. Galphas and Galphai bind to the catalytic domain and change the conformation of Src, leading to increased accessibility of the active site to substrates. These data demonstrate that the Src family tyrosine kinases are direct effectors of G proteins.
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Affiliation(s)
- Y C Ma
- Department of Physiology, Cornell University Medical College, New York, New York 10021, USA
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20
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Gu C, Ma YC, Benjamin J, Littman D, Chao MV, Huang XY. Apoptotic signaling through the beta -adrenergic receptor. A new Gs effector pathway. J Biol Chem 2000; 275:20726-33. [PMID: 10767282 DOI: 10.1074/jbc.m000152200] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.5] [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: 11/06/2022] Open
Abstract
Stimulation of beta-adrenergic receptor normally results in signaling by the heterotrimeric G protein G(s), leading to the activation of adenylyl cyclase, production of cAMP, and activation of cAMP-dependent protein kinase (PKA). Here we report that cell death of thymocytes can be induced after stimulation of beta-adrenergic receptor, or by addition of exogenous cAMP. Apoptotic cell death in both cases was observed with the appearance of terminal deoxynucleotidyl transferase-mediated UTP end labeling reactivity and the activation of caspase-3 in S49 T cells. Using thymocytes deficient in either Galpha(s) or PKA, we find that engagement of beta-adrenergic receptors initiated a Galpha(s)-dependent, PKA-independent pathway leading to apoptosis. This alternative pathway involves Src family tyrosine kinase Lck. Furthermore, we show that Lck protein kinase activity can be directly stimulated by purified Galpha(s). Our data reveal a new signaling pathway for Galpha(s), distinct from the classical PKA pathway, that accounts for the apoptotic action of beta-adrenergic receptors.
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Affiliation(s)
- C Gu
- Graduate Program of Cell Biology and Genetics, Graduate Program of Physiology, Biophysics and Molecular Medicine, and the Department of Physiology, Cornell University Medical College, New York, New York 10021, USA
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21
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Abstract
Heterotrimeric G proteins and tyrosine kinases are two major cellular signal transducers. Although G proteins are known to activate tyrosine kinases, the activation mechanism is not clear. Here, we demonstrate that G protein Gqalpha binds directly to the nonreceptor Bruton's tyrosine kinase (Btk) to a region composed of a Tec-homology (TH) domain and a sarcoma virus tyrosine kinase (Src)-homology 3 (SH3) domain both in vitro and in vivo. Only active GTP-bound Gqalpha, not inactive GDP-bound Gqalpha, can bind to Btk. Mutations of Btk that disrupt its ability to bind Gqalpha also eliminate Btk stimulation by Gqalpha, suggesting that this interaction is important for Btk activation. Remarkably, the structure of this TH (including a proline-rich sequence) -SH3 fragment of the Btk family of tyrosine kinases shows an intramolecular interaction. Furthermore, the crystal structure of the Src family of tyrosine kinases reveals that the intramolecular interaction of SH3 and its ligand is the major determining factor keeping the kinase inactive. Thus, we propose an activation model that entails binding of Gqalpha to the TH-SH3 region, thereby disrupting the TH-SH3 intramolecular interaction and activating Btk.
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Affiliation(s)
- Y C Ma
- Department of Physiology, Cornell University Medical College, 1300 York Avenue, New York, NY 10021, USA
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22
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Garcia MC, Ward G, Ma YC, Salem N, Kim HY. Effect of docosahexaenoic acid on the synthesis of phosphatidylserine in rat brain in microsomes and C6 glioma cells. J Neurochem 1998; 70:24-30. [PMID: 9422343 DOI: 10.1046/j.1471-4159.1998.70010024.x] [Citation(s) in RCA: 72] [Impact Index Per Article: 2.8] [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: 02/05/2023]
Abstract
Docosahexaenoic acid (22:6n-3) is the major polyunsaturated fatty acid (PUFA) in the CNS and accumulates particularly in phosphatidylserine (PS). We have investigated the effect of the 22:6n-3 compositional status on the synthesis of PS. The fatty acid composition of brain microsomes from offspring of rats artificially reared on an n-3-deficient diet showed a dramatic reduction of 22:6n-3 content (1.7 +/- 0.1%) when compared with control animals (15.0 +/- 0.2%). The decrease was accompanied by an increase in docosapentaenoic acid (22:5n-6) content, which replaced the 22:6n-3 phospholipids with 22:5n-6 molecular species, as demonstrated using HPLC/electrospray mass spectrometry. The n-3 deficiency did not affect the total amount of polyunsaturated phospholipids in brain microsomes; however, it was associated with a decrease in the total polyunsaturated PS content and with increased levels of 1-stearoyl-2-docosapentanoyl (18:0/22:5n-6) species, particularly in phosphatidylcholine. Incorporation of [3H]serine into PS in rat brain microsomes from n-3-deficient animals was slightly but significantly less than that of the control animals. Similarly, C6 glioma cells cultured for 24 h in 22:6n-3-supplemented media (10-40 microM) showed a significant increase in the synthesis of [3H]PS when compared with unsupplemented cells. Our data show that neuronal and glial PS synthesis is sensitive to changes in the docosahexaenoate levels of phospholipids and suggest that 22:6n-3 may be a modulator of PS synthesis.
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Affiliation(s)
- M C Garcia
- Laboratory of Membrane Biochemistry and Biophysics, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Rockville, Maryland 20852, USA
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23
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Sun JR, Ma YC, Xu ZH, Zhao WJ, Cai YP. [Effect of norepinephrine on the thermosensitive neurons in preoptic area of hypothalamus tissue slices in cold acclimatized rats]. Sheng Li Xue Bao 1997; 49:666-70. [PMID: 9863189] [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: 02/09/2023]
Abstract
In this work, single unit firing activities were recorded in the preoptic anterior hypothalamus (POAH) brain slices of cold acclimatized and room-temperature housed rats (CR and RR) and the effects of NE on the neuronal discharges were observed. The neurons of POAH in CR became much more sensitive to NE than that in RR (the threshold concentration of NE of CR became significantly lowered). In comparison with RR, the percentage of warm sensitive neurons that could be excited by NE was decreased and some of them even showed inhibitory responses. On the other hand, the percentage of cold sensitive neurons that could be inhibited by NE was decreased and some of them even showed excitatory responses. The percentage of thermo-insensitive neurons that could be either excited or inhibited by NE were increased.
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Affiliation(s)
- J R Sun
- College of Life Sciences, Peking University, Beijing
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24
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Sun JR, Ma YC, Zhao WJ, Cai YP. [Adaptive changes of preoptic thermosensitive neurons in hypothalamic tissue slices of rats after long-term exposure to cold environmental temperature]. Sheng Li Xue Bao 1996; 48:424-30. [PMID: 9387772] [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: 02/05/2023]
Abstract
In the present work, thermosensitivity and spontaneous firing rate of 86 preoptic neurons in hypothalamic tissue slices from 20 cold acclimated rats (CR, at 5 +/- 1 degrees C for more than 3 weeks) and 127 neurons from 35 warm acclimated rats (WR, at 20 +/- 3 degrees C for the same period) were recorded and compared. The results showed that: (1) The percentage of cold-sensitive neurons in CR were higher than that in WR, the critical temperature and the lowest temperature of the spontaneous firing activity of cold-sensitive neurons in CR were also lower than that in WR. (2) Thermosensitivity and critical temperature of the warm-sensitive neurons in CR were remarkably decreased, and spontaneous firing rate under 37 degrees C was increased. (3) Spontaneous firing rate (37 degrees C) of temperature insensitive neurons in CR were conspicuously increased and the lowest temperature extended downward. These profound changes in response to long-term cold exposure suggested that plasticity of preoptic neurons was involved in the thermoregulation in cold adaptation.
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Affiliation(s)
- J R Sun
- Department of Physiology, College of Life Sciences, Peking University, Beijing
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25
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Chi TW, Ma YC. Spontaneous rectus sheath hematoma during treatment of pulmonary embolism with warfarin: report of a case. Kaohsiung J Med Sci 1996; 12:601-4. [PMID: 8918082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
We present a case of a patient suffering from acute abdomen with a palpable mass on the left lower quadrant of the abdominal wall. The clinical manifestations and plain abdomen gave the misleading diagnosis of a ventral hernia. A review of the patient history revealed the use of anticoagulants for pulmonary embolism, and as a result computed tomography (CT) was performed which provided an accurate diagnosis of rectus sheath hematoma. The probable pathogenesis is discussed.
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Affiliation(s)
- T W Chi
- Department of Radiology, Mackay Memorial Hospital, Taipei, Taiwan, Republic of China
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26
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Saruta F, Hirawake H, Takamiya S, Ma YC, Aoki T, Sekimizu K, Kojima S, Kita K. Cloning of a cDNA encoding the small subunit of cytochrome b558 (cybS) of mitochondrial fumarate reductase (complex II) from adult Ascaris suum. Biochim Biophys Acta 1996; 1276:1-5. [PMID: 8764887 DOI: 10.1016/0005-2728(96)00070-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Complex II in the mitochondria of the adult parasitic nematode, Ascaris suum, exhibits high fumarate reductase activity in addition to succinate dehydrogenase activity and plays a key role in the anaerobic energy metabolism of the worm. In this study, the amino acid sequence of the small subunit of cytochrome b558 (cybS) in adult complex II was deduced from the cDNA isolated by immunoscreening an A. suum muscle cDNA library. Histidine residues, which are possible heme axial ligands in cytochrome b558, were found in the second transmembrane segment of the subunit. This is the first report of the primary structure of the small subunit in the two-subunit cytochrome b in mitochondrial complex II from a multicellular eukaryote.
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Affiliation(s)
- F Saruta
- Department of Parasitology, University of Tokyo, Japan
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27
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Abstract
Release of specific polyunsaturated fatty acids for cell membranes may have a significant implication in biological function, considering the involvement of various fatty acids in cell signal transduction. In the present study, release of polyunsaturated fatty acids from rat brain synaptosomes by endogenous synaptosomal lipase activity was examined in comparison to that by cobra venom phospholipase A2 (Naja naja naja). Cobra venom phospholipase A2 (Naja naja naja) preferentially hydrolyzed docosahexaenoic acid (22:6n-3) from both synaptosomes and lipid mixtures containing similar classes of lipids commonly found in the brain. Arachidonic acid (20:4n-6) and oleic acid (18:1n-9) were also hydrolyzed; however, monoene species was hydrolyzed slower than were polyenoic species in synaptosomes. Phosphatidylethanolamine was the most preferred phospholipid class for release of 22:6n-3 fatty acid from both lipid mixtures and synaptosomes. In contrast to hydrolysis by cobra venom phospholipase A2, endogenous synaptosomal lipase activity preferentially hydrolyzed 20:4n-6 from rat brain synaptosomes, despite the high abundance of 22:6n-3 in synaptosomal membranes. Preferential release of 20:4n-6 was observed over a wide range of pH values and calcium concentrations. Synaptosomal 22:6 species appeared to be resistant to hydrolysis even after stimulation with various agents such as phorbolmyristate, suggesting that physiological importance of 22:6n-3 in neuronal membranes may not be as the release fatty acid.
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Affiliation(s)
- H Y Kim
- Section of Mass Spectrometry, National Institute of Alcohol Abuse and Alcoholism, National Institutes of Health, Rockville, Maryland 20892, USA
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28
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Chi TW, Shih SL, Ma YC. Retroperitoneal lipoblastoma: report of one case. Zhonghua Min Guo Xiao Er Ke Yi Xue Hui Za Zhi 1995; 36:376-7. [PMID: 8607366] [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: 01/31/2023]
Abstract
A one-year-old boy presented with progressive distension of the abdomen occurring over a few months. Computed tomography (CT) scan demonstrated a large, well-defined retroperitoneal mass with heterogeneous attenuation appearance and areas of low density showing as fatty substance. Slight enhancement of the soft tissue components was also noted. Reviewing of the literature indicates an accurate preoperative diagnosis of such fatty tumor is allowed by analysis of patient's age, tumor location, and characteristic CT pictures.
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Affiliation(s)
- T W Chi
- Department of Radiology, Mackay Memorial Hospital, Taipei, Taiwan, R.O.C
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Ma YC, Kim HY. Development of the on-line high-performance liquid chromatography/thermospray mass spectrometry method for the analysis of phospholipid molecular species in rat brain. Anal Biochem 1995; 226:293-301. [PMID: 7793631 DOI: 10.1006/abio.1995.1228] [Citation(s) in RCA: 43] [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: 01/27/2023]
Abstract
An on-line thermospray liquid chromatography/mass spectrometry method was developed to rapidly analyze phosphoglyceride molecular species in biological fluid. After total lipid extraction, the extract was subjected to the analysis using on-line reversed-phase high-performance liquid chromatography (HPLC) and filament-on thermospray mass spectrometry. Using nonconventional HPLC conditions, partial separation of individual phospholipid class (phosphatidylserine, phosphatidylinositol, phosphatidylethanolamine, and phosphatidylcholine) and partial separation of molecular species within each class were achieved. In addition, good peak shape was maintained throughout the analysis. By monitoring characteristic fragment ions (diacylglycerol ions) formed in the filament-on thermospray process and according to the retention time, individual molecular species in each phospholipid class can be identified. Using this method, we observed significant differences in the molecular species composition of each phospholipid class in rat whole-brain lipid. Although nonlinear calibration curves were observed for all the diacylglycerol ions monitored, even in the presence of internal standard, semiquantitative and quantitative results still could be obtained for a mixture of phospholipids.
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Affiliation(s)
- Y C Ma
- Section of Mass Spectrometry, LMBB, NIAAA, National Institutes of Health, Bethesda, Maryland 20892, USA
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Abstract
Malignant hemangioendothelioma is an uncommon lesion of the omentum in children. Multiple foci of malignant hemangioendothelioma is even more rare in the omentum. In the present case, a computed tomography scan of the abdomen showed multiple enhanced nodular lesions. To our knowledge, this is the first report of this tumor occurring in a child.
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Affiliation(s)
- S L Shih
- Department of Radiology, MacKay Memorial Hospital, Taipei, Taiwan, Republic of China
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Wang YJ, Ma YC. [Angiography for the management of poorly controlled gastrointestinal hemorrhage--20 cases clinical observation]. Gaoxiong Yi Xue Ke Xue Za Zhi 1995; 11:43-8. [PMID: 7707450] [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: 01/26/2023]
Abstract
Diagnostic and therapeutic angiography has demonstrated an important role in gastrointestinal hemorrhage. During the past 2 years, we performed angiography in the management of 20 patients with uncontrolled gastrointestinal bleeding. Conservative management including medication and transfusion would not appear to suffice in these patients and most patients had been evaluated to have a high operative risk in our series. Ten of the 20 patients had renal dysfunction (creatinine > 1.7 mg/dl) before angiography. The role of angiography in the management of patients with renal dysfunction remains controversial because angiography is likely to produce acute renal failure. We performed angiography to stop bleeding in these patients with renal dysfunction because they could die of blood loss. In our 20 cases, bleeding sites were identified in 14 patients. The detection rate was 70%. Thirteen of the 14 with the use of either vasopressin infusion or arterial embolization showed complete cessation of bleeding in 10 patients. Three cases failed to be controlled. One received an operation after a bleeding site was located by angiography. In our study, sepsis with renal failure was the leading cause of mortality (6 cases). Ten patients with pre-existing renal dysfunction had angiography performed and only one showed abrupt elevation of creatinine levels after angiography. He also developed sepsis. Deterioration of renal function was possibly due to angiography or more likely due to sepsis and hypovolemia. Six patients died of sepsis after angiography although 4 of these patients showed cessation of bleeding. Four cases with pre-existing renal dysfunction and without evidence of infection survived after angiographic management.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- Y J Wang
- Department of Radiology, Min Shen General Hospital, Taipei, Republic of China
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Abstract
An improved technique for phospholipid molecular species analysis was developed using high-performance liquid chromatography/mass spectrometry with the electrospray interface. Using the 0.5% ammonium hydroxide in a water-methanol-hexane mixture and a C-18 column, complex mixtures of phospholipid molecular species were separated and detected mainly as protonated or natriated molecular species. The response was linear over 2 orders of magnitude, allowing quantification of each molecular species. In comparison to the existing LC/MS techniques, marked improvement in sensitivity was observed. The present quantification limit is approximately 0.5 pmol before split (5 fmol after 1/100 split). The relative responses were more dependent on the head group identity rather than fatty acyl composition within a phospholipid class. In general, phosphatidylcholine (PC) species are most sensitively detected followed by phosphatidylethanolamine (PE) species. The sensitivity of phosphatidylserine (PS) in the positive ion mode is approximately 20 times less in comparison to PC under our condition.
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Affiliation(s)
- H Y Kim
- Section of Mass Spectrometry, NIAAA, NIH, Bethesda, Maryland 20892
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Chi TW, Pang KK, Ma YC, Yang FS. Use of computed tomography to detect hepatic portal venous gas and intestinal intramural gas: a case report. Zhonghua Yi Xue Za Zhi (Taipei) 1994; 53:124-6. [PMID: 8167989] [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: 01/29/2023]
Abstract
Hepatic portal venous gas and intestinal intramural gas were demonstrated by computed tomography (CT) in a case of ischemic bowel disease. The patient died on the day following the examination.
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Affiliation(s)
- T W Chi
- Department of Radiology, Mackay Memorial Hospital, Taipei, Taiwan, R.O.C
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Abstract
An intravascular foreign body is an iatrogenic complication that occurs during arterial or venous catheterization or interventional procedures. The foreign body could either be a catheter fragment, a dislodged coil, or a steel guide wire. From January 1987 to December 1992, 12 cases of intravascular foreign-body removals were performed by a percutaneous method at Mackay Memorial Hospital. Of the 12 cases, five were dislodged steel guide wires, four were broken CVP catheters, two were dislodged coils, and one was Port-A fragment. The techniques we used were the loop-snare technique (two cases) and stone basket retriever (10 cases). Eleven cases of intravascular foreign bodies were removed by non-surgical percutaneous retrieval but one case was a failure due to improper extraction of a dislodged steel guide wire. The patient received surgical extraction by regional venotomy finally. No major complications were noted during or after these procedures.
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Affiliation(s)
- F S Yang
- Department of Radiology, Mackay Memorial Hospital, Taipei, Taiwan, ROC
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Abstract
Small cell carcinoma of the stomach is a rare neoplasm. We report the barium meal and computed tomography findings of a 70-year-old man who presented with a long history of postprandial abdominal pain.
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Affiliation(s)
- T W Chi
- Department of Radiology, Mackay Memorial Hospital, Taitung, Taiwan, People's Republic of China
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Duran E, Komuniecki RW, Komuniecki PR, Wheelock MJ, Klingbeil MM, Ma YC, Johnson KR. Characterization of cDNA clones for the 2-methyl branched-chain enoyl-CoA reductase. An enzyme involved in branched-chain fatty acid synthesis in anaerobic mitochondria of the parasitic nematode Ascaris suum. J Biol Chem 1993; 268:22391-6. [PMID: 7693666] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
The 2-methyl branched-chain enoyl-CoA reductase plays a pivotal role in the reversal of beta-oxidation operating in anaerobic mitochondria of the parasitic nematode Ascaris suum. An affinity-purified polyclonal anti-serum against the reductase was used to screen a cDNA library constructed in lambda gt11 with poly(A)+ RNA from adult A. suum muscle. A 1.2-kilobase partial cDNA clone was isolated, subcloned, and sequenced in both directions. Additional sequence at the 5' end of the mRNA was determined by the RACE (rapid amplification of cDNA ends) procedure. Nucleotide sequence analysis of the cDNAs revealed the 22-nucleotide trans-spliced leader sequence characteristic of many nematode mRNAs, an open reading frame of 1236 nucleotides and a 3'-untranslated sequence of 109 nucleotides including a short poly(A) tail 14 nucleotides from a polyadenylation signal (AATAAA). The open reading frame encoded a 396-amino acid sequence (M(r) 43,046) including a 16-amino acid leader peptide. Two-dimensional gel electrophoresis of the purified reductase yielded multiple spots with two distinct but overlapping amino-terminal amino acid sequences. Both sequences overlapped with the sequence predicted from the mRNA, and one of the sequences was identical to the predicted sequence. Comparison of the ascarid sequence with that of mammalian acyl-CoA dehydrogenases revealed a high degree of sequence identity, suggesting that these enzymes may have evolved from a common ancestral gene even though the ascarid enzyme functions as a reductase, not as a dehydrogenase. Immunoblotting of A. suum larval stages and adult tissues with antisera that cross-reacted with each of the spots separated on two-dimensional gels suggested that the reductase was only found in adult muscle. Northern blotting using the partial cDNA revealed a hybridization band of about 1.5 kilobases and also suggested that the enzyme was tissue-specific and developmentally regulated in agreement with the results of the immunoblotting.
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Affiliation(s)
- E Duran
- Department of Biology, University of Toledo, Ohio 43606
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Ma YC, Funk M, Dunham WR, Komuniecki R. Purification and characterization of electron-transfer flavoprotein: rhodoquinone oxidoreductase from anaerobic mitochondria of the adult parasitic nematode, Ascaris suum. J Biol Chem 1993; 268:20360-5. [PMID: 8376393] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Electron-transfer flavoprotein:rhodoquinone oxidoreductase (ETF-RO) was purified to homogeneity from anaerobic mitochondria of the parasitic nematode, Ascaris suum. The enzyme has a subunit molecular mass of 64.5 kDa and is similar in many respects to the electron-transfer flavoprotein:ubiquinone oxidoreductase (ETF-UO) characterized in mammalian tissues. EPR spectroscopy of the purified enzyme revealed signals at g = 2.076, 1,936, and 1.883, arising from an iron-sulfur center, as well as signals attributable to a flavin semiquinone. Potentiometric titration on the enzyme with dithionite yielded an oxidation-reduction midpoint potential (Em) for the iron-sulfur center of +25 mV at pH 7.4. The reduction of flavin occurred in two distinct steps, with a flavin semiquinone radical detected as an intermediate. The Em values for the two steps in the complete reduction of flavin were +15 mV and -9 mV, respectively. Physiologically, the ascarid ETF-RO accepts electrons from a low potential quinone, rhodoquinone, and functions in a direction opposite to that of the ETF-UO. Incubations of A. suum submitochondrial particles with NADH, 2-methylcrotonyl-CoA, purified A. suum electron-transfer flavoprotein and 2-methyl branched-chain enoyl-CoA reductase resulted in significant 2-methylbutyryl-CoA formation, which was inhibited by both rotenone and antisera to the purified ETF-RO. Quinone extraction of the submitchondrial particles with dry pentane resulted in almost the complete loss of 2-MBCoA formation by the system. However, the reincorporation of rhodoquinone, but not ubiquinone restored over 50% of the NADH-dependent 2-MBCoA formation.
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Affiliation(s)
- Y C Ma
- Department of Biology, University of Toledo, Ohio 43606
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Ruff HA, Bijur PE, Markowitz M, Ma YC, Rosen JF. Declining blood lead levels and cognitive changes in moderately lead-poisoned children. JAMA 1993; 269:1641-6. [PMID: 8455297] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
OBJECTIVE To determine whether chelation therapy or biochemical changes during a lead-lowering intervention was associated with changes in cognitive functioning of moderately lead-poisoned children. It was hypothesized that cognitive performance would improve as blood lead level declined over time. DESIGN Short-term intervention study with measures obtained before and after intervention. SETTING Hospital specialty clinic and university research center. PATIENTS A total of 154 previously untreated children referred to clinic with blood lead levels between 1.21 and 2.66 mumol/L (25 and 55 micrograms/dL) at time of enrollment. Ages ranged from 13 to 87 months. INTERVENTION Enrolled children were treated with edetate calcium disodium (EDTA) if eligible and/or with orally administered iron supplement if iron deficient. For all children, housing inspections and abatement procedures were performed as necessary. MAIN OUTCOME MEASURES Score on Bayley Mental Development Scale or Stanford-Binet Intelligence Scale (4th edition). RESULTS There was no effect of edetate calcium disodium treatment per se. In the short term (7 weeks), changes in blood lead levels were not related to changes in cognitive scores. In the long term (6 months), however, changes in performance were significantly related to changes in blood lead level, even after controlling for confounding variables. The standardized score increased 1 point for every decrease of 0.14 mumol/L (3 micrograms/dL) in blood lead level. CONCLUSION The results suggest an association between decreases in blood lead level and cognitive improvements in moderately lead-poisoned children.
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Affiliation(s)
- H A Ruff
- Department of Pediatrics, Albert Einstein College of Medicine, Montefiore Medical Center, Bronx, NY
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Kita K, Takamiya S, Furushima R, Ma YC, Suzuki H, Ozawa T, Oya H. Electron-transfer complexes of Ascaris suum muscle mitochondria. III. Composition and fumarate reductase activity of complex II. Biochim Biophys Acta 1988; 935:130-40. [PMID: 2843227 DOI: 10.1016/0005-2728(88)90210-1] [Citation(s) in RCA: 53] [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] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Complex II of the anaerobic respiratory chain in Ascaris muscle mitochondria showed a high fumarate reductase activity when reduced methyl viologen was used as the electron donor. The maximum activity was 49 mumol/min per mg protein, which is much higher than that of the mammalian counterpart. The mitochondria of Ascaris-fertilized eggs, which require oxygen for its development, also showed fumarate reductase activity with a specific activity intermediate between those of adult Ascaris and mammals. Antibody against the Ascaris flavoprotein subunit reacted with the mammalian counterparts, whereas those against the Ascaris iron-sulfur protein subunit did not crossreact, although the amino acid compositions of the subunits in Ascaris and bovine heart were quite similar. Cytochrome b-558 of Ascaris complex II was separated from flavoprotein and iron-sulphur protein subunits by high performance liquid chromatography with a gel permeation system in the presence of Sarkosyl. Isolated cytochrome b-558 is composed of two hydrophobic polypeptides with molecular masses of 17.2 and 12.5 kDa determined by gradient gel, which correspond to the two small subunits of complex II. Amino acid compositions of these small subunits showed little similarity with those of cytochrome b-560 of bovine heart complex II. NADH-fumarate reductase, which is the final enzyme complex in the anaerobic respiratory chain in Ascaris, was reconstituted with bovine heart complex I, Ascaris complex II and phospholipids. The maximum activity was 430 nmol/min per mg protein of complex II. Rhodoquinone was essential for this reconstitution, whereas ubiquinone showed no effect. The results clearly indicate the unique role of Ascaris complex II as fumarate reductase and the indispensability of rhodoquinone as the low-potential electron carrier in the NADH-fumarate reductase system.
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Affiliation(s)
- K Kita
- Department of Parasitology, Juntendo University, School of Medicine, Tokyo, Japan
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Hsu JC, Yang TL, Chen JS, Ma YC. [Biliary enteric fistula]. Zhonghua Yi Xue Za Zhi (Taipei) 1988; 41:293-8. [PMID: 3052742] [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: 01/03/2023]
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Ma YC, Ho TL, Chang CS, Yao PH, Cheng CF. Experimental studies on treatment of renal trauma. Chin Med J 1965; 84:460-5. [PMID: 5865196] [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: 01/17/2023]
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