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Li S, Mu D, Ma C, Yixicuomu, Zhaxiyangzong, Pang J, Zhan M, Liu Z, Dan Q, Cheng X. Establishment of a reference interval for total carbon dioxide using indirect methods in Chinese populations living in high-altitude areas: A retrospective real-world analysis. Clin Biochem 2023; 119:110631. [PMID: 37572984 DOI: 10.1016/j.clinbiochem.2023.110631] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Revised: 08/03/2023] [Accepted: 08/09/2023] [Indexed: 08/14/2023]
Abstract
BACKGROUND Hypoxia leads to different concentrations of the bicarbonate buffer system in Tibetan people. Indirect methods were used to establish the reference interval (RI) for total carbon dioxide (tCO2) based on big data from the adult population of Tibet, a high-altitude area in Western China. METHODS Anonymous tCO2 test data (n = 442,714) were collected from the People's Hospital of the Tibet Autonomous Region from January 2018, to December 2021. Multiple linear regression and variance component analyses were performed to assess the effects of sex, age, and race on tCO2 levels. Indirect methods, including Hoffmann, Bhattacharya, expectation maximization (EM), kosmic and refineR, were used to calculate the total RI and ethnicity-partitioned RI. RESULTS A total of 230,821 real-world tCO2 test results were eligible. Sex, age, and race were significantly associated with the tCO2 levels. The total and ethnically-partitioned RIs estimated using the five indirect methods were comparable. The total RI of tCO2 was 14-24 mmol/L (calculated using Hoffmann and refineR) and 15-24 mmol/L (Bhattacharya, EM and kosmic). For Han nationality, the RIs were 14-25 mmol/L (calculated using Hoffmann and Bhattacharya), 16-23 mmol/L (EM), 15-24 mmol/L (kosmic), and 14.2-24.5 mmol/L (refineR). For the Tibetan population, the RIs were 14-24 mmol/L (calculated using Hoffmann and refineR), 15-24 mmol/L (Bhattacharya and kosmic), and 15-23 mmol/L (EM). The established RIs were significantly lower than those living at lower altitudes area (22-29 mmol/L) that was provided by the manufacturer. CONCLUSION The tCO2 RI of the populations living on the Tibetan Plateau was significantly lower than those at the lower altitudes. The RIs established using indirect methods are suitable for clinical applications in Tibet.
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Affiliation(s)
- Shensong Li
- Department of Clinical Laboratory, People's Hospital of Tibet Autonomous Region, Lhasa, China
| | - Danni Mu
- Department of Laboratory Medicine, Peking Union Medical College Hospital, Peking Union Medical College & Chinese Academy of Medical Science, Beijing, China
| | - Chaochao Ma
- Department of Laboratory Medicine, Peking Union Medical College Hospital, Peking Union Medical College & Chinese Academy of Medical Science, Beijing, China
| | - Yixicuomu
- Department of Clinical Laboratory, People's Hospital of Tibet Autonomous Region, Lhasa, China
| | - Zhaxiyangzong
- Department of Clinical Laboratory, People's Hospital of Tibet Autonomous Region, Lhasa, China
| | - Jinrong Pang
- Department of Clinical Laboratory, People's Hospital of Tibet Autonomous Region, Lhasa, China
| | - Mingjun Zhan
- Department of Clinical Laboratory, People's Hospital of Tibet Autonomous Region, Lhasa, China
| | - Zhijuan Liu
- Department of Clinical Laboratory, People's Hospital of Tibet Autonomous Region, Lhasa, China.
| | - Qu Dan
- Department of Clinical Laboratory, People's Hospital of Tibet Autonomous Region, Lhasa, China.
| | - Xinqi Cheng
- Department of Laboratory Medicine, Peking Union Medical College Hospital, Peking Union Medical College & Chinese Academy of Medical Science, Beijing, China.
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Chen S, Mima D, Jin H, Dan Q, Wang F, Cai J, Shi L, Wang H, Du A, Tang Y, Sun Y. The Association between Neprilysin gene polymorphisms and Alzheimer's disease in Tibetan population. Brain Behav 2021; 11:e02002. [PMID: 33314757 PMCID: PMC7994707 DOI: 10.1002/brb3.2002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Accepted: 11/29/2020] [Indexed: 12/22/2022] Open
Abstract
OBJECTIVES Alzheimer's disease (AD) is a well-known neurodegenerative disease, of which the hallmark is the disposition of β-amyloid (Aβ) in the form of plaque in the brain. Neprilysin (NEP) is the major enzyme to degrade Aβ and prevent accumulation of Aβ. The present study was undertaken to elucidate the correlation between the NEP gene polymorphisms and AD in Chinese Tibetan population. METHODS Ninety-nine sporadic AD Tibetan patients and 113 healthy Tibetan controls were enrolled in this study. The genotype frequencies and allele frequencies of multiple NEP gene loci were analyzed using the case-control association analysis. RESULTS No significant correlation was found between polymorphisms of NEP gene loci (rs9829757, rs1816558, rs6776185, rs3736187, rs701109, rs989692) and the occurrence of AD in Tibetan population. However, allele C of NEP gene locus (rs701109) and allele T of gene locus (rs3736187) were possible risk factors of male AD patients in Tibetan population. CONCLUSIONS NEP gene loci (rs701109, rs989692, rs9829757, rs3736187, rs1816558, rs6776185) were polymorphic in Tibetan population. No difference was found between these loci but for that male gender combined with allele C of NEP gene locus (rs701109) and T of gene locus (rs3736187) might be risk factors for AD in Tibet.
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Affiliation(s)
- Siwei Chen
- Department of Neurology, Peking University First Hospital, Beijing, China
| | - Dunzhu Mima
- Department of Neurology, People's Hospital of Tibet Autonomous Region, Tibet Autonomous Region, China
| | - Haiqiang Jin
- Department of Neurology, Peking University First Hospital, Beijing, China
| | - Qu Dan
- Clinical Laboratory, People's Hospital of Tibet Autonomous Region, Tibet Autonomous Region, China
| | - Fei Wang
- Department of Neurology, Harbin Medical University First Hospital, Harbin, China
| | - Juan Cai
- Department of Neurology, Harbin Medical University First Hospital, Harbin, China
| | - Lin Shi
- Shenzhen BrainNow Research Institute, Shenzhen, China
| | - Huali Wang
- Beijing Dementia Key Lab, National Clinical Research Center for Mental Disorders, Peking University Institute of Mental Health (Sixth Hospital), Beijing, China
| | - Ailian Du
- Department of Neurology, Tongren Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Ying Tang
- Department of Neurology, Harbin Medical University First Hospital, Harbin, China
| | - Yongan Sun
- Department of Neurology, Peking University First Hospital, Beijing, China
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Shi YJ, Sun YF, Gao L, Chen YD, Wang JL, Dan Q, Zhang Y. [Value of fragmented QRS wave in evaluating the prognosis of patients with coronary artery disease]. Zhonghua Yi Xue Za Zhi 2017; 97:3-6. [PMID: 28056281 DOI: 10.3760/cma.j.issn.0376-2491.2017.01.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Objective: The aim of the current study was to investigate the predictive value of fragmented QRS wave ( fQRS) for the prognosis of patients with coronary heart disease (CHD). Methods: A total of 714 consecutive patients with confirmed CHD were included from Department of Cardiology, General Hospital of PLA between January 2013 and January 2014, and were divided into fQRS group and non-fQRS group based on the presence of fQRS wave or not according to Electrocardiograph (ECG). The baseline, ECG characteristic value, the echocardiography results of the patients were compared between the two groups. Cardiac events were recorded in all patients during 12 months' follow-up. Subgroup analysis was also conducted among patients with abnormal Q wave to investigate the association between fQRS and cardiovascular events. Results: A total of 673 patients completed the follow-up, with 533 in fQRS group and 140 in non-fQRS group. The P wave duration in the fQRS group was longer than non-fQRS group [(92±21) vs (82±23)ms, P<0.01]. The left ventricular ejection fraction (LVEF) value in the fQRS group was lower than non-fQRS group (42%±22% vs 49%±15%, P<0.01) according to echocardiography results. The subgroup analysis with abnormal Q wave showed that compared with non-fQRS group, the left ventricular ejection fraction (LVEF) value in the group of fQRS was lower (38%±21% vs 50%±7%, P<0.01). There was statistically significant in the mortality of patients within follow-up period between the two groups (P<0.05), and the survival time in fQRS group was shorter than the non-fQRS group [(28.3±3.4) vs (30.5±1.5)months, P<0.01]. Conclusion: FQRS presence in body surface ECG of CHD patients with abnormal Q wave is a sign for increased risk of cardiovascular events, which can serve as an indicator to identify CHD patients at high risk of death.
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Affiliation(s)
- Y J Shi
- Department of Cardiology, General Hospital of PLA, Beijing 100853, China
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Shen ZQ, Hua M, Dan Q, Lu J, Fang JP. [Spatial pattern analysis and associations of Quercus aquifolioides population at different growth stages in Southeast Tibet, China]. Ying Yong Sheng Tai Xue Bao 2016; 27:387-394. [PMID: 27396109] [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: 06/06/2023]
Abstract
This article analyzed the spatial pattern and its correlation of Quercus aquifolioides, Southeast Tibet at different growing stages by using Ripley' s L function in the method of point pattern, analysis. The results showed the diameter structure of Q. aquifolioides population in Southeast Tibet followed a 'single peak' shape and the saplings and medium trees predominated in number in the whole population. The population had a high regeneration rate and was of increase type. In the growth process of Q. aquifolioides from saplings to large trees, saplings and medium trees showed aggregation distribution at.small scale, while large trees showed basically random distribution at whole scale. There was significant correlation between saplings with medium or large trees at small scale, however, there was no correlation between medium and large trees. In the growth process of Q. aquifolioides population from saplings, medium trees to large trees, its spatial pattern developed from aggregative distribution to random distribution. The natural regeneration of Q. aquifolioides population was affected not only by interspecific competition, but also by intraspecific competition. In the similar natural environment, the most important factors affecting the spatial pattern of Q. aquifoioides population were its own biological and ecological characteristics.
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Ailenberg M, Di Ciano-Oliveira C, Szaszi K, Dan Q, Rozycki M, Kapus A, Rotstein OD. Dynasore enhances the formation of mitochondrial antiviral signalling aggregates and endocytosis-independent NF-κB activation. Br J Pharmacol 2015; 172:3748-63. [PMID: 25850711 DOI: 10.1111/bph.13162] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2014] [Revised: 02/18/2015] [Accepted: 03/31/2015] [Indexed: 01/02/2023] Open
Abstract
BACKGROUND AND PURPOSE Dynasore has been used extensively as an inhibitor of clathrin-mediated endocytosis. While studying the role of endocytosis in LPS-induced signalling events, we discovered that dynasore itself induced activation of NF-κB, independently of its effects on endocytosis and without involving the Toll-like receptor 4 signalling pathways. The purpose of this study was to characterize this novel effect and to explore the underlying mechanism of action. EXPERIMENTAL APPROACH We utilized gel electrophoresis, microscopy, gene knockdown and luciferase-based promoter activity to evaluate the effect of dynasore on cell signalling pathways and to delineate the mechanisms involved in its effects, KEY RESULTS Dynasore activated the NF-κB and IFN-β pathways by activating mitochondrial antiviral signalling protein (MAVS). We showed that MAVS is activated by NOX/Rac and forms high molecular weight aggregates, similar to that observed in response to viral infection. We also demonstrated that dynasore-induced activation of JNK occurs downstream of MAVS and is required for activation of NF-κB and IFN-β. CONCLUSION AND IMPLICATIONS These findings demonstrate a novel effect of dynasore on cell signalling. We describe a novel Rac1-, ROS- and MAVS-mediated signalling cascade through which dynasore dramatically activates NF-κB, mimicking the viral induction of this key inflammatory signalling pathway. Our results call attention to the need for a broader interpretation of results when dynasore is used in its traditional fashion as an inhibitor of clathrin-mediated endocytosis. These results suggest the intriguing possibility that dynasore or one of its analogues might be of value as an antiviral therapeutic strategy or vaccine adjuvant.
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Affiliation(s)
- M Ailenberg
- Departments of Surgery, St. Michael's Hospital, Toronto, ON, Canada.,University of Toronto, Toronto, ON, Canada.,Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, ON, Canada
| | - C Di Ciano-Oliveira
- Departments of Surgery, St. Michael's Hospital, Toronto, ON, Canada.,University of Toronto, Toronto, ON, Canada.,Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, ON, Canada
| | - K Szaszi
- Departments of Surgery, St. Michael's Hospital, Toronto, ON, Canada.,University of Toronto, Toronto, ON, Canada.,Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, ON, Canada
| | - Q Dan
- Departments of Surgery, St. Michael's Hospital, Toronto, ON, Canada.,University of Toronto, Toronto, ON, Canada.,Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, ON, Canada
| | - M Rozycki
- Departments of Surgery, St. Michael's Hospital, Toronto, ON, Canada.,University of Toronto, Toronto, ON, Canada.,Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, ON, Canada
| | - A Kapus
- Departments of Surgery, St. Michael's Hospital, Toronto, ON, Canada.,University of Toronto, Toronto, ON, Canada.,Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, ON, Canada
| | - O D Rotstein
- Departments of Surgery, St. Michael's Hospital, Toronto, ON, Canada.,University of Toronto, Toronto, ON, Canada.,Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, ON, Canada
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Dan Q, Yin S, Wong R, Chung S, Chung S, Lam K. 1P-0137 Interaction between the polyol pathway and non-enzymatic glycation on aortic smooth muscle cell migration and monocyte adhesion in a transgenic mouse model. ATHEROSCLEROSIS SUPP 2003. [DOI: 10.1016/s1567-5688(03)90211-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Dan Q, Sanchez R, Delgado C, Wepsic HT, Morgan K, Chen Y, Jeffes EW, Lowell CA, Morgan TR, Jadus MR. Non-immunogenic murine hepatocellular carcinoma Hepa1-6 cells expressing the membrane form of macrophage colony stimulating factor are rejected in vivo and lead to CD8+ T-cell immunity against the parental tumor. Mol Ther 2001; 4:427-37. [PMID: 11708879 DOI: 10.1006/mthe.2001.0477] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Hepatocellular carcinoma is a lethal disease and methods that develop effective cellular-based immunotherapy are needed. We retrovirally transduced non-immunogenic mouse Hepa1-6 hepatoma cells with the gene encoding the membrane form of macrophage colony stimulating factor (mM-CSF). Excess recombinant M-CSF and phagocytosis-inhibiting chemicals blocked macrophage-mediated killing of cloned mM-CSF transfected Hepa1-6 hepatoma cells. Macrophages derived from Hck(-/-)Fgr(-/-) and Lyn(-/-) triple knockout mice, which are incapable of performing phagocytosis, failed to kill the mM-CSF transduced cells. The mM-CSF transfected tumor clones failed to grow when injected into C57BL/6 or C57L/J mice. Splenocytes from these vaccinated mice displayed cytotoxicity against parental Hepa1-6 cells, but not against B16 and CT-26 tumor cells in vitro. Mice that rejected the mM-CSF transfected Hepa1-6 tumor subsequently rejected parental Hepa1-6 cells but not the B16 melanoma cells when rechallenged. Elimination of the CD8+ effector cells by an anti-CD8 antibody and complement treatment prevented the adoptive transfer of anti-Hepa1-6-specific immunity into naive animals. Thus, mM-CSF provides a method of generating effective anti-tumor immune responses by macrophages and cytotoxic T cells against the parental Hepa1-6 cells. Our work suggests that mM-CSF transduced hepatoma cells could be used as a tumor vaccine to stimulate immune responses against hepatocellular carcinoma.
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Affiliation(s)
- Q Dan
- Diagnostic and Molecular Medicine Health Care Group, Veterans Affairs Medical Center, University of California, 5901 E. 7th Street, Long Beach, CA 90822, USA
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Dan Q, Trinh H, Williams CC, Lloyd C, Wepsic HT, Jeffes EW, Jadus MR. Dexamethasone increases the expression of membrane macrophage colony stimulating factor from retrovirally transduced tumor cells expressing macrophage colony stimulating factor. Int Immunopharmacol 2001; 1:737-48. [PMID: 11357885 DOI: 10.1016/s1567-5769(01)00007-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Many different tumor cell types (breast, ovarian, glioma, liver and colon) were retrovirally transduced with the human macrophage colony stimulating factor (M-CSF) gene (either the membrane associated form [mM-CSF] or the secreted form [sM-CSF]). These cells were tested for their ability to display increased amounts of mM-CSF in response to dexamethasone. M-CSF-transfected tumor cells expressed additional mM-CSF in response to 18-72 h incubations with 3-15 microg/ml dexamethasone, while non-transfected parental cells were unaffected by this treatment. Increased mM-CSF protein expression on the M-CSF transduced cells was observed by flow cytometry and Western blotting using M-CSF specific antibodies. Northern blot analysis revealed an increase in the mM-CSF specific transcripts within the dexamethasone-treated mM-CSF transduced cells, but this was not seen within the non-transfected tumor cells that were treated with dexamethasone. ICAM-1 expression was unaffected by dexamethasone treatment, indicating that this response is mM-CSF specific. All trans-retinal and 1,25-dihydroxy vitamin D3 compounds that have been reported to induce M-CSF expression failed to increase mM-CSF. When dexamethasone-treated mM-CSF transfected clones were used as target cells for macrophage-mediated cytotoxicity assays, an increased killing with the dexamethasone-treated cells was seen. The macrophage-mediated cytotoxicity of these mM-CSF expressing tumor cells was blocked with excess recombinant M-CSF by saturating M-CSF receptors on the macrophage that is required for this form of tumor cell killing. This work suggests the possibility that dexamethasone may prove useful for vaccination purposes using mM-CSF retrovirally transfected tumor cells.
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Affiliation(s)
- Q Dan
- Diagnostic and Molecular Medicine Health Care Group, Veterans Affairs Medical Center, Long Beach, CA 90822, USA
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Williams CC, Trinh H, Tran TV, Dan Q, Sanchez R, Delgado C, Chen Y, Sippel B, Jeffes EW, Wepsic HT, Jadus MR. Membrane macrophage colony-stimulating factor on MADB106 breast cancer cells does not activate cytotoxic macrophages but immunizes rats against breast cancer. Mol Ther 2001; 3:216-24. [PMID: 11237678 DOI: 10.1006/mthe.2001.0253] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Weakly immunogenic, but highly malignant, rat MADB106 breast cancer cells were retrovirally transduced with the membrane form of macrophage colony-stimulating factor (mM-CSF). The cloned mM-CSF-transfected MADB106 cells physically conjugated with macrophages, but were not killed by the macrophages in 48-h cytotoxicity assays. Macrophages killed the mM-CSF-expressing tumors in the presence of noncytotoxic doses of either taxol or taxol plus cisplatin. This indicated that macrophages bind to the mM-CSF expressed on the tumor cells, but for successful macrophage cytotoxicity to occur against mM-CSF-transduced tumor cells other factors must be present. The mM-CSF-transfected tumor cells were rejected when inoculated subcutaneously into normal rats. Cloned MADB106 tumor cells which expressed high amount of mM-CSF were rejected, while tumor cells that displayed lower levels of mM-CSF grew in 60% of the inoculated rats. The mM-CSF-transfected tumors that grew were smaller and had a greater amount of necrosis, compared to the viral vector tumors. Rats that spontaneously rejected the mM-CSF-transfected MADB106 cells showed rechallenge resistance to unmodified parental MADB106 and R3230Ac breast cancers, but not to the F98 glioma. These observations suggest that breast cancer-specific immunity was induced by the inoculation of mM-CSF-expressing MADB106 tumor cells.
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Affiliation(s)
- C C Williams
- Department of Laboratory Service, Box 113, Veterans Affairs Medical Center, 5901 East 7th Street, Long Beach, California 90822, USA
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Dan Q, Huang Y, Peng Z. [DNA polymorphisms of the apolipoprotein AI-CIII-AIV gene cluster in coronary artery disease]. Zhonghua Yi Xue Za Zhi 1995; 75:584-7, 637. [PMID: 8697070] [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: 02/01/2023]
Abstract
Two polymorphic sites of the apolipoprotein AI (ApoAI) gene, PstI and SstI, were examined in a sample of 43 unrelated Chinese patients with coronary artery disease (CAD) and 60 unrelated healthy individuals. Allele frequencies were compared between patients and controls and their impact on lipid and oxygen free radicals metabolism were also studied. The frequencies of the uncommon P2 and S2 alleles in CAD cases were found as 0.14 and 0.22 respectively, which were significantly higher than 0.05 and 0.13 in controls. The more the number of vessel disease in CAD cases, the higher the frequencies of S2 alleles which were the highest in the group of 3 vessel diseases. Some serum lipid and oxygen free radicals levels differed between CAD cases of different genotypes. These data suggest that genetic variation in P2 and S2 alleles of APOAI gene may contribute to the development and extent of CAD in Chinese subjects.
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Affiliation(s)
- Q Dan
- Cardiovascular Institute, Zhejiang Medical University, Hangzhou
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Abstract
In this article some topics related to the MYCIN-model for uncertainty handling are discussed. First, it is pointed out that one of the problems identified by Adams should be considered as evidence supporting the point of view that the probabilistic interpretations of measures of belief and measures of disbelief given by Shortliffe are inappropriate. In this context some results achieved by Heckerman are reviewed, and it is shown that similar problems can be identified in the interpretation given by him. It is also pointed out that Heckerman's argument that the original probabilistic interpretation of certainty factors implies non-commutative evidence-updating is not correct. Then, in the context of the result achieved by Horvitz and Heckerman, in which it was proven that there is an isomorphic mapping from the evidence combination scheme for the likelihood ratio to the evidence combination function in EMYCIN and its successors, it is pointed out that the evidence combination scheme for the likelihood ratio suffers from a great restriction on its applicability in expert systems. Subsequently, some short remarks are made with respect to the complaint that sometimes the MYCIN model cannot work as well as expected. Lastly implementation of the certainty factor mechanism in a HIS-oriented expert system shell with some substantial changes is described.
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Affiliation(s)
- Q Dan
- Institute for Medical Informatics, University Giessen, Germany
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