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Ye H, Hu WH, Chen XX, Zhao BQ, Zhang WX, Chen XM. Heat- and Pressure-driven Room-temperature Polymorphic Transition Accompanied with Switchable SHG Signal in a New Chiral Hexagonal Perovskite. Chem Asian J 2023; 18:e202300608. [PMID: 37553296 DOI: 10.1002/asia.202300608] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Revised: 08/06/2023] [Accepted: 08/08/2023] [Indexed: 08/10/2023]
Abstract
Endowing room-temperature polymorphs with both long-term stability and easy interconvertibility is a big challenge due to the complexity of intermolecular interactions. Herein, we present a chiral hexagonal perovskite (R-3-hydroxy-1-methylpiperidinium)[CdCl3 ] having two room-temperature crystalline forms featuring obviously distinct second-harmonic-generation (SHG) signals with a high switching contrast of ~18 times. The two room-temperature forms could be long-term stable yet easily interconvertible through an irreversible thermal-induced phase transition and a pressure-driven backward transition, by switching hydrogen bonds via collective reorientation of ordered homochiral cations. Based on the essential role of homochiral organic cations in inducing switchable hydrogen bond linkages, this present instance provides good evidence that relatively irregular organic cations could induce more obvious inorganic chain deformations, thus endowing polymorphs with significantly different SHG signals at room temperature.
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Affiliation(s)
- Hui Ye
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Chemistry, IGCME, Sun Yat-sen University, Guangzhou, 510275, China
| | - Wang-Hua Hu
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Chemistry, IGCME, Sun Yat-sen University, Guangzhou, 510275, China
| | - Xiao-Xian Chen
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Chemistry, IGCME, Sun Yat-sen University, Guangzhou, 510275, China
| | - Bing-Qing Zhao
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Chemistry, IGCME, Sun Yat-sen University, Guangzhou, 510275, China
| | - Wei-Xiong Zhang
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Chemistry, IGCME, Sun Yat-sen University, Guangzhou, 510275, China
| | - Xiao-Ming Chen
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Chemistry, IGCME, Sun Yat-sen University, Guangzhou, 510275, China
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Zhao BQ, Chen XX, Ye H, Gong YP, Wang J, Ye L, Zhang WX. An anomalous ferroelastic phase transition arising from an unusual cis-/ anti-conformational reversal of polar organic cations. Chem Sci 2023; 14:5965-5973. [PMID: 37293638 PMCID: PMC10246694 DOI: 10.1039/d3sc01101a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Accepted: 04/30/2023] [Indexed: 06/10/2023] Open
Abstract
Hybrid ferroelastics have attracted increasing attention for their potential application as mechanical switches. The sporadically documented anomalous ferroelastic phase transitions, i.e., ferroelasticity that appears at a high-temperature phase rather than a low-temperature phase, are of particular interest but are not well understood at the molecular level. By judiciously choosing a polar and flexible organic cation (Me2NH(CH2)2Br+) with cis-/anti- conformations as an A-site component, we obtained two new polar hybrid ferroelastics, A2[MBr6] (M = Te for 1 and Sn for 2). These materials undergo distinct thermal-induced ferroelastic phase transitions. The larger [TeBr6]2- anions anchor the adjacent organic cations well and essentially endow 1 with a conventional ferroelastic transition (P21 → Pm21n) arising from a common order-disorder transition of organic cations without conformational changes. Moreover, the smaller [SnBr6]2- anions can interact with the adjacent organic cations in energetically similar sets of intermolecular interactions, enabling 2 to undergo an anomalous ferroelastic phase transition (P212121 → P21) arising from an unusual cis-/anti-conformational reversal of organic cations. These two instances demonstrate the importance of the delicate balance of intermolecular interactions for inducing anomalous ferroelastic phase transitions. The findings here provide important insights for seeking new multifunctional ferroelastic materials.
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Affiliation(s)
- Bing-Qing Zhao
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Chemistry, Sun Yat-Sen University Guangzhou 510275 China
| | - Xiao-Xian Chen
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Chemistry, Sun Yat-Sen University Guangzhou 510275 China
| | - Hui Ye
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Chemistry, Sun Yat-Sen University Guangzhou 510275 China
| | - Ya-Ping Gong
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Chemistry, Sun Yat-Sen University Guangzhou 510275 China
| | - Jun Wang
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Chemistry, Sun Yat-Sen University Guangzhou 510275 China
| | - Le Ye
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Chemistry, Sun Yat-Sen University Guangzhou 510275 China
| | - Wei-Xiong Zhang
- MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Chemistry, Sun Yat-Sen University Guangzhou 510275 China
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Ye H, Chen XX, Liu DX, Zhao BQ, Li YB, Zeng Y, Zhang WX, Chen XM. Subtly tuning intermolecular hydrogen bonds in hybrid crystals to achieve ultrahigh-temperature molecular ferroelastic. Chem Sci 2022; 13:14124-14131. [DOI: 10.1039/d2sc04112j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2022] [Accepted: 11/06/2022] [Indexed: 11/10/2022] Open
Abstract
Molecule-based ferroic phase-transition materials attracted increasing attentions in the past decades due to their promising potentials as sensors, switches, and memories. One of long-term challenges in the development of molecule-based...
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Li JG, Chen XH, Ge H, Qin X, Jing XG, Wang GZ, Mao DW, Zhuang GY, Zhao BQ. [Clinical significance of low-dose CT performed for three consecutive years in diagnosis of lung nodules in coal mine workers with 20 working years]. Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi 2018; 35:679-682. [PMID: 29294521 DOI: 10.3760/cma.j.issn.1001-9391.2017.09.009] [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 clinical significance of low-dose CT (LDCT) in coal mine workers with relatively long working years. Methods: A total of 907 coal mine workers with ≥20 working years were enrolled, among whom there were 863 male and 44 female workers with a mean age of 49.5 years. Digital radiography (DR) was performed for these workers in 2013, and LDCT was performed for three consecutive years from 2014 to 2016. Results: A total of 32 workers were found to have lung nodules by DR in 2013, while in 2014, 269 workers were found to have non-calcified lung nodules by LDCT, and there was a significant difference in the number of workers with lung nodules (χ(2)=233.73, P<0.005) . There was also a significant difference in the detection rate of nodules between the workers with different working years of dust exposure (χ(2)=6.648, P=0.00) . The male workers had a significantly higher detection rate of nodules than the female workers (χ(2)=5.690, P=0.017) . There was no significant difference in the number of nodules between workers with different types of work (χ(2)=16.985, P=0.05) . There were 443 lung nodules in total, among which 71.56% were solid nodules and 55.75% had a size of ≤4mm; malignant nodules were confirmed by surgery in 6 (0.66%) of the 907 workers after baseline LDCT. LDCT reexamination in 2015 and 2016 found new nodules in 8 workers and enlarged nodules in 3 workers, and there was no significant change in the number of nodules with a size of ≤4 mm. Conclusions: It is necessary to perform high-risk population screening for coal mine workers by LDCT. The follow-up strategies for nodules with a size of ≤4mm are the same as those for negative results; annual reexamination is recommended for nodules with a size of >4-8 mm, and clinical treatment should be considered for nodules with a size of >8 mm.
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Affiliation(s)
- J G Li
- Department of Radiology, China Ping Mei Shen Ma Medical Group General Hospital, Pingdingshan, Henan Province 467000, China
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Fan DX, Xu RW, Li YC, Zhao BQ, Sun MY. Impact of the number of examined lymph nodes on outcomes in patients with lymph node-negative gallbladder carcinoma. World J Gastroenterol 2018; 24:2886-2892. [PMID: 30018483 PMCID: PMC6048429 DOI: 10.3748/wjg.v24.i26.2886] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Revised: 05/02/2018] [Accepted: 06/01/2018] [Indexed: 02/06/2023] Open
Abstract
AIM To determine whether the number of examined lymph nodes (LNs) is correlated with the overall survival of gallbladder carcinoma (GBC) patients.
METHODS Patients were collected from the Surveillance Epidemiology and End Results database (2004-2013) and categorized by the number of LNs into six groups: 1 LN, 2 LNs, 3 LNs, 4 LNs, 5 LNs, and ≥ 6 LNs. Survival curves for overall survival were plotted with a Kaplan-Meier analysis. The log-rank test was used for univariate comparisons.
RESULTS In a cohort of 893 patients, the median number of examined LNs was two for the entire cohort. The survival for the 1 LN group was significantly poorer than those of the stage I and II disease groups and for the entire cohort. By dichotomizing the number of LNs from 1 to 6, we found that the minimum number of LNs that should be examined was four for stage I, four or five for stage II, and six for stage IIIA disease. Therefore, for the entire cohort, the number of examined LNs should be at least six, which is exactly consistent with the American Joint Committee on Cancer criteria.
CONCLUSION The examination of higher numbers of LNs is associated with improved survival after resection surgery for N0 GBC. The guidelines for GBC surgery, which recommend that six LNs be examined at least, are statistically valid and should be applied in clinical practice widely.
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Affiliation(s)
- Dong-Xu Fan
- Department of Vascular surgery, First Affiliated Hospital of Jiamusi University, Jiamusi 154002, Heilongjiang Province, China
| | - Rong-Wei Xu
- Department of Vascular Surgery, Shandong Provincial Qianfoshan Hospital, Shandong University, Jinan 250014, Shandong Province, China
| | - Yong-Cheng Li
- Department of Medical Oncology, Xuzhou Central Hospital, The Affiliated Xuzhou Hospital of Medical College of Southeast University, Xuzhou 221009, Jiangsu Province, China
| | - Bing-Qing Zhao
- Department of Surgery, Tianjin Second People’s Hospital, Tianjin 300192, China
| | - Ming-Yu Sun
- Department of Breast Surgery, Xuzhou Central Hospital, The Affiliated Xuzhou Hospital of Medical College of Southeast University, Xuzhou 221009, Jiangsu Province, China
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Yu HF, Zhao BQ, Li YC, Fu J, Jiang W, Xu RW, Yang HC, Zhang XJ. Stage III should be subclassified into Stage IIIA and IIIB in the American Joint Committee on Cancer (8 th Edition) staging system for pancreatic cancer. World J Gastroenterol 2018; 24:2400-2405. [PMID: 29904247 PMCID: PMC6000291 DOI: 10.3748/wjg.v24.i22.2400] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Revised: 04/05/2018] [Accepted: 05/05/2018] [Indexed: 02/06/2023] Open
Abstract
AIM To ascertain the prognostic role of the T4 and N2 category in stage III pancreatic cancer according to the 8th edition of the American Joint Committee on Cancer (AJCC) classification.
METHODS Patients were collected from the Surveillance Epidemiology and End Results (SEER) database (2004-2013) and were divided into three groups: T(1-3)N2, T4N(0-1), and T4N2. Overall survival (OS) and disease-specific survival (DSS) of patients were evaluated by the Kaplan-Meier method.
RESULTS For the first time, we found a significant difference in OS and DSS between T(1-3)N2/T4N(0-1) and T4N2 but not between T(1-3)N2 and T4N(0-1). A higher grading correlated with a worse prognosis in the T(1-3)N2 and T4N2 groups.
CONCLUSION Patients with stage T4N2 had a worse prognosis than those with stage T(1-3)N2/T4N(0-1) in the 8th edition AJCC staging system for pancreatic cancer. We recommend that stage III should be subclassified into stage IIIA [T(1-3)N2/T4N(0-1)] and stage IIIB (T4N2).
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Affiliation(s)
- Hai-Feng Yu
- Department of General Surgery, Tianjin First Central Hospital, Tianjin 300192, China
| | - Bing-Qing Zhao
- Department of Surgery, Tianjin Second People’s Hospital, Tianjin 300192, China
| | - Yong-Cheng Li
- Department of Medical Oncology, XuZhou Central Hospital, The Affiliated XuZhou Hospital of Medical College of Southeast University, Xuzhou 221009, Jiangsu Province, China
| | - Jun Fu
- Department of Hepatic-Biliary-Pancreatic-Splenic Surgery, XuZhou Central Hospital, The Affiliated XuZhou Hospital of Medical College of Southeast University, Xuzhou 221009, China
| | - Wei Jiang
- Department of General Surgery, Tianjin First Central Hospital, Tianjin 300192, China
| | - Rong-Wei Xu
- Department of Vascular Surgery, Shandong Provincial Qianfoshan Hospital, Shandong University, Jinan 250014, China
| | - Hao-Chang Yang
- College of Clinical Medicine, Binzhou Medical University, Yantai 264003, China
| | - Xiao-Jun Zhang
- Department of Hepatic-Biliary-Pancreatic-Splenic Surgery, XuZhou Central Hospital, The Affiliated XuZhou Hospital of Medical College of Southeast University, Xuzhou 221009, China
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Zhao YF, Zhao BQ, Ma KJ, Zhang J, Chen FY. [Forensic Analysis for 54 Cases of Suxamethonium Chloride Poisoning]. Fa Yi Xue Za Zhi 2017; 33:374-375. [PMID: 29219267 DOI: 10.3969/j.issn.1004-5619.2017.04.008] [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] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Indexed: 11/18/2022]
Abstract
OBJECTIVES To observe and analyze the performance of forensic science in the cases of suxa- methonium chloride poisoning, and to improve the identification of suxamethonium chloride poisoning. METHODS Fifty-four cases of suxamethonium chloride poisoning were collected. The rules of determination of suxamethonium chloride poisoning were observed by the retrospective analysis of pathological and toxicological changes as well as case features. RESULTS The pathological features of suxamethonium chloride poisoning were similar to the general changes of sudden death, which mainly included acute pulmonary congestion and edema, and partly showed myocardial disarray and fracture. Suxamethonium chloride could be detected in the heart blood of all cases and in skin tissue of part cases. CONCLUSIONS Suxa-methonium chloride poisoning has the characteristics with fast death and covert means, which are difficult to rescue and easily miss inspection. For the cases of sudden death or suspicious death, determination of suxamethonium chloride should be taken as a routine detection index to prevent missing inspection.
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Affiliation(s)
- Y F Zhao
- Suzhou Municipal Public Security Bureau, Suzhou 234000, China
| | - B Q Zhao
- Suzhou Municipal People's Procuratorate, Suzhou 234000, China
| | - K J Ma
- Suzhou Municipal Public Security Bureau, Suzhou 234000, China
| | - J Zhang
- Suzhou Municipal Public Security Bureau, Suzhou 234000, China
| | - F Y Chen
- Suzhou Municipal Public Security Bureau, Suzhou 234000, China
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Zhao CX, Wang YQ, Wang YJ, Zhang HL, Zhao BQ. [Temporal and spatial distribution of PM2.5 and PM10 pollution status and the correlation of particulate matters and meteorological factors during winter and spring in Beijing]. Huan Jing Ke Xue 2014; 35:418-427. [PMID: 24812928] [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: 06/03/2023]
Abstract
Fogs and hazes broke out many times in winter and spring of 2012-2013 in Beijing, inducing severe pollution of respirable particulate matters (PM10). As a fine particle component in PM10, PM2.5 would cause more severe air pollution if the proportion of PM2.5 to PM10 is high. Based on this, 30 monitoring stations recording the concentration of PM2.5 and PM1.0 all over Beijing were selected, and the contamination characteristics of particulate matters were analyzed, which further served to determine the characteristics of temporal and spatial pollution variations of PM2.5 and PM10. The distribution of PM2.5 and PM10 mass concentration in winter and spring in Beijing were derived by the Original Kriging interpolation method, and it was depicted from the figure that the concentration of particulate matters gradually increased from the northern mountain area to the southern part of Beijing; in the central urban area, the particulate concentration of the western region was generally higher than that of the eastern region, with certain differences between urban and rural area within some local areas. Monthly variation curve of PM2.5 and PM10 mass concentration showed single peak-valley pattern: the maximum was in January and the minimum was in April; daily variation indicated a good correlation between PM2.5 and PM10, both of which were significantly influenced by meteorological conditions; diurnal variation curve showed a double peak-valley type. Meteorological factors such as daily average temperature (degrees C), relative humidity (%), wind speed (wind scale), precipitation (mm) were chosen and their individual relationships with concentrations of PM10 and PM2.5 were investigated using Spearman rank correlation analyses. It was demonstrated that the concentrations of PM10 and PM2.5 were positively correlated with temperature and relative humidity, respectively, and strongly negatively correlated with wind speed; wind speed and relative humidity were two key factors affecting the distributions of PM2.5 and PM10 concentration.
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Suzuki Y, Kondo K, Matsumoto Y, Zhao BQ, Otsuguro K, Maeda T, Tsukamoto Y, Urano T, Umemura K. Dietary supplementation of fermented soybean, natto, suppresses intimal thickening and modulates the lysis of mural thrombi after endothelial injury in rat femoral artery. Life Sci 2003; 73:1289-98. [PMID: 12850244 DOI: 10.1016/s0024-3205(03)00426-0] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.9] [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: 01/14/2023]
Abstract
We have previously demonstrated that natto-extracts containing nattokinase (NK) inactivates plasminogen activator inhibitor type 1 and then potentiates fibrinolytic activity. In the present study, we investigated the effects of dietary supplementation with natto-extracts on neointima formation and on thrombolysis at the site of endothelial injury. Endothelial damage in the rat femoral artery was induced by intravenous injection of rose bengal followed by focal irradiation by transluminal green light. Dietary natto-extracts supplementation containing NK of 50 or 100 CU/body was started 3 weeks before endothelial injury and then continued for another 3 weeks. Intimal thickening in animals given supplementation was significantly (P<0.01) suppressed compared with controls and the intima/media ratio in animals with 50 and 100 CU/body NK and control group was 0.09 +/- 0.03, 0.09 +/- 0.06 and 0.16 +/- 0.12, respectively. Although femoral arteries were reopened both in control animals and those treated with NK within 8 hours after endothelial injury, mural thrombi were histologically observed at the site of endothelial injury. In the control group, the center of vessel lumen was reopened and mural thrombi were attached on the surface of vessel walls. In contrast, in NK-treated groups, thrombi near the vessel wall showed lysis and most of them detached from the surface of vessel walls. In conclusion, dietary natto-extracts supplementation suppressed intimal thickening produced by endothelial injury in rat femoral artery. These effects may partially be attributable to NK, which showed enhanced thrombolysis near the vessel wall.
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Affiliation(s)
- Yasuhiro Suzuki
- Department of Pharmacology, Hamamatsu University School of Medicine, 1-20-1 Handayama, Hamamatsu City, Shizuoka 431-3192, Japan.
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Zhao BQ, Suzuki Y, Kondo K, Ikeda Y, Umemura K. Combination of a free radical scavenger and heparin reduces cerebral hemorrhage after heparin treatment in a rabbit middle cerebral artery occlusion model. Stroke 2001; 32:2157-63. [PMID: 11546911 DOI: 10.1161/hs0901.095640] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE We sought to investigate the effects of EPC-K1, a free radical scavenger, on reducing heparin-produced cerebral hemorrhage in a rabbit model of middle cerebral artery (MCA) photothrombosis and to investigate whether the combination of EPC-K1 and heparin enhances neuroprotection from cerebral ischemic damage. METHODS In the heparin-alone group (n=8), heparin was administered intravenously for 24 hours, starting from 3 hours after MCA occlusion. In the EPC-K1-alone group (n=8), EPC-K1 was administered as a bolus injection (10 mg/kg) twice at 3 and 6 hours after MCA occlusion. In the combination group (n=8), EPC-K1 and heparin both were administered as in the single-drug procedures. In the vehicle group (n=10), saline were infused for 24 hours. RESULTS Heparin prolonged activated partial thromboplastin time by approximately 3 times that of control animals. In the heparin-treated animals, the hemorrhage size was significantly increased (P<0.0001) and neurological symptoms were significantly worse (P<0.01) than in control animals at 48 hours. The combination of EPC-K1 and heparin dramatically reduced heparin-produced cerebral hemorrhage (P<0.0001), with a significant reduction in infarct volume (reduction by 63.2% and 57.2% of heparin-alone and control animals, respectively, P<0.0001) and a significant improvement in neurological symptoms (P<0.01 versus heparin-alone and control animals, respectively). CONCLUSIONS These data indicate that free radical formation may play a key role in intracerebral hemorrhage exacerbated by heparin treatment and that the combination of a free radical scavenger and heparin augmented neuroprotection from acute brain ischemia. The results of the present study may suggest a potential clinical approach for the treatment of acute stroke.
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Affiliation(s)
- B Q Zhao
- Department of Pharmacology, Hamamatsu University School of Medicine, Hamamatsu, 431-3192, Japan
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Zhao BQ, Suzuki Y, Kondo K, Kawano K, Ikeda Y, Umemura K. Cerebral hemorrhage due to heparin limits its neuroprotective effects: studies in a rabbit model of photothrombotic middle cerebral artery occlusion. Brain Res 2001; 902:30-9. [PMID: 11376592 DOI: 10.1016/s0006-8993(01)02285-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
We investigated the efficacy of heparin on cerebral ischemic damage in a rabbit model of middle cerebral artery (MCA) photothrombosis and in the same model, cerebral hemorrhage induced by heparin as its side effect was also investigated. Using a photothrombosis model in rabbits, 38 animals were divided into four groups, heparin low-dose I and II, heparin high-dose and vehicle. In heparin low-dose I (n=10) or II (n=7), heparin was administered for 23.5 or 22 h, respectively, starting 30 or 120 min after the start of photo-irradiation to induce thrombosis. In high-dose (n=7), heparin was administered 30 min after the start of photo-irradiation for 23.5 h. In the vehicle treated group (control), 14 animals were infused continuously with saline for 23.5 h. Heparin at low and high doses prolonged Activated partial thromboplastin time (aPTT) by about 3 and 10 times compared with control group. The results show that cerebral hemorrhage was present in all animals, gross hemorrhage was observed in one animal each of the heparin low-dose I and high-dose groups, and in three animals of the heparin low-dose II group, while no gross hemorrhage was observed in control group. In heparin low-dose I, the size of cerebral infarction was significantly (P<0.01) reduced and neurological deficits were significantly (P<0.01) improved. In contrast, in heparin high-dose, the infarct size significantly increased, especially in the cortex (P<0.0001), and neurological deficits were significantly (P<0.01) worsened. In heparin low-dose II, the size of cerebral hemorrhage significantly (P<0.001) increased compared with the control group. In conclusion, using a photothrombotic model in the rabbit MCA, we have investigated the antithrombotic benefits and hemorrhagic risks associated with heparin. Of unique feature of our model is the fact that in a single animal model, we could evaluate doses of heparin which reduce cerebral infarction and doses which can promote cerebral hemorrhage. This model can be extended to determine both benefits and risks of antithrombotic agents.
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Affiliation(s)
- B Q Zhao
- Department of Pharmacology, Hamamatsu University School of Medicine, 1-20-1 Handayama, 431-3192, Hamamatsu, Japan
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