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Liu JL, Jin JW, Lin LL, Lai ZM, Wang JB, Su JS, Zhang LC. Emergency tracheal intubation peri-operative risk factors and prognostic impact after esophagectomy. BMC Anesthesiol 2022; 22:367. [PMID: 36456899 PMCID: PMC9714176 DOI: 10.1186/s12871-022-01918-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Accepted: 11/18/2022] [Indexed: 12/03/2022] Open
Abstract
BACKGROUND Emergent endotracheal intubation (ETI) is a serious complication after Oesophagectomy. It is still unclear that perioperative risk factors and prognosis of these patients with ETI. METHODS Between January 2015 and December 2018, 21 patients who received ETI after esophagectomy were enrolled (ETI group) at the department of thoracic surgery, Fujian Union hospital, China. Each study subject matched one patient who underwent the same surgery in the current era were included (control group). Patient characteristics and perioperative factors were collected. RESULTS Patients with ETI were older than those without ETI (p = 0.022). The patients with history of smoking in ETI group were significantly more than those in control group (p = 0.013). The stay-time of postanesthesia care unit (PACU) in ETI group was significantly longer than that in control group (p = 0.001). The incidence of anastomotic leak or electrolyte disorder in ETI group was also higher than that in control group (p = 0.014; p = 0.002). Logistic regression analysis indicated history of smoke (HR 6.43, 95%CI 1.39-29.76, p = 0.017) and longer stay time of PACU (HR 1.04, 95%CI 1.01-1.83, p = 0.020) both were independently associated with higher risks of ETI. The 3-year overall survival (OS) rates were 47.6% in patients with ETI and 85.7% in patients without ETI (HR 4.72, 95%CI 1.31-17.00, p = 0.018). COX regression analysis indicated ETI was an independent risk factor affecting the OS. CONCLUSION The study indicated that history of smoking and longer stay-time in PACU both were independently associated with higher risks of ETI; and ETI was an independent risk factor affecting the OS of patients after esophagectomy. TRIAL REGISTRATION This trial was retrospectively registered with the registration number of ChiCTR2000038549.
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Affiliation(s)
- Jun-Le Liu
- grid.411176.40000 0004 1758 0478Department of anesthesiology, Union Hospital, Fujian Medical University, XinQuan Road 29th, 350001 Fuzhou, Fujian China
| | - Jian-Wen Jin
- Department of Clinical Medicine, Fujian Health College, 366th GuanKou, 350101 Fuzhou, Fujian China
| | - Li-Li Lin
- grid.411176.40000 0004 1758 0478Department of anesthesiology, Union Hospital, Fujian Medical University, XinQuan Road 29th, 350001 Fuzhou, Fujian China
| | - Zhong-Meng Lai
- grid.411176.40000 0004 1758 0478Department of anesthesiology, Union Hospital, Fujian Medical University, XinQuan Road 29th, 350001 Fuzhou, Fujian China
| | - Jie-Bo Wang
- grid.411176.40000 0004 1758 0478Department of anesthesiology, Union Hospital, Fujian Medical University, XinQuan Road 29th, 350001 Fuzhou, Fujian China
| | - Jian-Sheng Su
- grid.411176.40000 0004 1758 0478Department of anesthesiology, Union Hospital, Fujian Medical University, XinQuan Road 29th, 350001 Fuzhou, Fujian China
| | - Liang-Cheng Zhang
- grid.411176.40000 0004 1758 0478Department of anesthesiology, Union Hospital, Fujian Medical University, XinQuan Road 29th, 350001 Fuzhou, Fujian China
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Chen KC, Rathore AZ, Deol T, Liu KL, Wu EW, Su JS, Wannenburg TW, Catanzaro JNC. COVID-19 associated Brugada pattern electrocardiogram: systematic review of case reports. Eur Heart J 2022. [PMCID: PMC9619525 DOI: 10.1093/eurheartj/ehac544.385] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
Objective To summarize published case reports of patients diagnosed with COVID-19 infection and Brugada pattern electrocardiogram (ECG). Background Fever is a common clinical manifestation of COVID-19 infection. Fever has also been associated with unmasking Brugada pattern ECG in patients and may result in life-threatening arrhythmia. Little is known regarding COVID-19 associated Brugada pattern ECG. There is paucity of data and guidance in how to manage these patients. Methods To identify all published case reports, the latest Preferred Reporting Items for Systematic Reviews and Meta-Analyses checklist was followed. A literature search was conducted using PubMed, EMBASE, and Scopus through September 2021. A systematic review was performed to identify the incidence, clinical characteristics, and management outcomes of COVID-19 patients with a Brugada pattern ECG. Results A total of 18 cases were collected. The mean age was 47.1 years and 11.1% were women. No patient had prior confirmed diagnosis of Brugada syndrome. The most common presenting clinical symptoms were fever (83.3%), chest pain (38.8%), shortness of breath (38.8%), and syncope (16.6%). All 18 patients presented with type 1 Brugada pattern ECG. Four patients (22.2%) underwent left heart catheterization, and none demonstrated the presence of obstructive coronary disease. The most common reported therapies included antipyretics (55.5%), hydroxychloroquine (27.7%), and antibiotics (16.6%). One patient (5.5%) died during hospitalization. Three patients (16.6%) who presented with syncope received either an implantable cardioverter defibrillator or wearable cardioverter defibrillator at discharge. At follow up, thirteen patients (72.2%) had resolution of type 1 Brugada pattern ECG. Conclusion COVID-19 associated Brugada pattern ECG is rare. Most patients may see resolution of the ECG pattern once their symptoms have improved. Increased awareness and timely use of antipyretics is warranted in this population. Funding Acknowledgement Type of funding sources: None.
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Affiliation(s)
- K C Chen
- University of Florida College of Medicine, Cardiology , Jacksonville , United States of America
| | - A Z Rathore
- University of Florida College of Medicine, Cardiology , Jacksonville , United States of America
| | - T Deol
- University of Florida College of Medicine, Cardiology , Jacksonville , United States of America
| | - K L Liu
- University of Florida College of Medicine, Cardiology , Jacksonville , United States of America
| | - E W Wu
- University of Florida College of Medicine, Cardiology , Jacksonville , United States of America
| | - J S Su
- University of Florida College of Medicine, Cardiology , Jacksonville , United States of America
| | - T W Wannenburg
- University of Florida College of Medicine, Cardiology , Jacksonville , United States of America
| | - J N C Catanzaro
- University of Florida College of Medicine, Cardiology , Jacksonville , United States of America
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Wang C, Xie PJ, Wu JH, Su JS. [Application of CAD in custom tray design for teaching of dental postgraduates]. Shanghai Kou Qiang Yi Xue 2022; 31:221-224. [PMID: 36110085] [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: 06/15/2023]
Abstract
PURPOSE To evaluate the teaching effect of making custom trays via CAD in dental postgraduates. METHODS Twenty-seven dental postgraduates from first to third grade at the School and Hospital of Stomatology, Tongji University, Shanghai were given an informed consent to explain and request participation in the study. First, a lecture about the theory and process of fabricating custom tray via traditional hand-made method and CAD technique was given, then the students fabricated custom trays via the two methods and completed an online survey. The working time, margin extension and students' preference were analyzed with SPSS 22.0 software package. RESULTS The working time was shorter, the margin extension was superior, and students' preference was higher via CAD than traditional method, the difference was significant(P<0.05). CONCLUSIONS CAD is more conducive to enhance students' understanding of custom tray manufacturing process and relevant theoretical knowledge. It is recommended to integrate digital technology into dental curriculum.
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Affiliation(s)
- Can Wang
- Department of Prosthodontics, School and Hospital of Stomatology, Tongji University. Shanghai 200072, China. E-mail:
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Liu JL, Jin JW, Lai ZM, Wang JB, Su JS, Wu GH, Chen WH, Zhang LC. Emergency tracheal intubation during off-hours is not associated with increased mortality in hospitalized patients: a retrospective cohort study. BMC Anesthesiol 2020; 20:265. [PMID: 33087063 PMCID: PMC7576761 DOI: 10.1186/s12871-020-01188-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2020] [Accepted: 10/14/2020] [Indexed: 11/18/2022] Open
Abstract
Background The prognosis of hospitalized patients after emergent endotracheal intubation (ETI) remains poor. Our aim was to evaluate the 30-d hospitalization mortality of subjects undergoing ETI during daytime or off-hours and to analyze the possible risk factors affecting mortality. Methods A single-center retrospective study was performed at a university teaching facility from January 2015 to December 2018. All adult inpatients who received ETI in the general ward were included. Information on patient demographics, vital signs, ICU (Intensive care unit) admission, intubation time (daytime or off-hours), the department in which ETI was performed (surgical ward or medical ward), intubation reasons, and 30-d hospitalization mortality after ETI were obtained from a database. Results Over a four-year period, 558 subjects were analyzed. There were more male than female in both groups (115 [70.1%] vs 275 [69.8%]; P = 0.939). A total of 394 (70.6%) patients received ETI during off-hours. The patients who received ETI during the daytime were older than those who received ETI during off-hours (64.95 ± 17.54 vs 61.55 ± 17.49; P = 0.037). The BMI of patients who received ETI during the daytime was also higher than that of patients who received ETI during off-hours (23.08 ± 3.38 vs 21.97 ± 3.25; P < 0.001). The 30-d mortality after ETI was 66.8% (373), which included 68.0% (268) during off-hours and 64.0% (105) during the daytime (P = 0.361). Multivariate Cox regression analysis found that the significant factors for the risk of death within 30 days included ICU admission (HR 0.312, 0.176–0.554) and the department in which ETI was performed (HR 0.401, 0.247–0.653). Conclusions The 30-d hospitalization mortality after ETI was 66.8%, and off-hours presentation was not significantly associated with mortality. ICU admission and ETI performed in the surgical ward were significant factors for decreasing the risk of death within 30 days. Trial registration This trial was retrospectively registered with the registration number of ChiCTR2000038549.
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Affiliation(s)
- Jun-Le Liu
- Department of anesthesiology, Union Hospital, Fujian Medical University, XinQuan Road 29th, Fuzhou, 350001, Fujian, China
| | - Jian-Wen Jin
- Department of Clinical Medicine, Fujian Health College, 366th GuanKou, Fuzhou, 350101, Fujian, China
| | - Zhong-Meng Lai
- Department of anesthesiology, Union Hospital, Fujian Medical University, XinQuan Road 29th, Fuzhou, 350001, Fujian, China
| | - Jie-Bo Wang
- Department of anesthesiology, Union Hospital, Fujian Medical University, XinQuan Road 29th, Fuzhou, 350001, Fujian, China
| | - Jian-Sheng Su
- Department of anesthesiology, Union Hospital, Fujian Medical University, XinQuan Road 29th, Fuzhou, 350001, Fujian, China
| | - Guo-Hua Wu
- Department of anesthesiology, Union Hospital, Fujian Medical University, XinQuan Road 29th, Fuzhou, 350001, Fujian, China
| | - Wen-Hua Chen
- Department of anesthesiology, Union Hospital, Fujian Medical University, XinQuan Road 29th, Fuzhou, 350001, Fujian, China
| | - Liang-Cheng Zhang
- Department of anesthesiology, Union Hospital, Fujian Medical University, XinQuan Road 29th, Fuzhou, 350001, Fujian, China.
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Chen LL, Han WF, Geng Y, Su JS. A genome-wide study of DNA methylation modified by epigallocatechin-3-gallate in the CAL-27 cell line. Mol Med Rep 2015; 12:5886-90. [PMID: 26239270 DOI: 10.3892/mmr.2015.4118] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Accepted: 03/03/2015] [Indexed: 11/05/2022] Open
Abstract
In order to gain greater understanding of the mechanisms underlying the effect of epigallocatechin-3-gallate (EGCG) on DNA methylation and its chemopreventative action in oral squamous cell carcinoma (OSCC), a genome‑wide methylation and mRNA expression screen was performed in the CAL‑27 cell line with and without EGCG (100 µM) treatment. A total of 761 differentially methylated gene loci were identified following treatment with EGCG. Comparison of gene expression profiling in OSCC samples revealed 184 transcripts with a significant difference (P<0.05) and a fold change difference >2 compared with controls. Gene ontology analysis of differentially methylated loci and functional annotation of the differentially expressed genes indicated that the main pathways involved were metabolic, mitogen‑activated protein kinase (MAPK), wnt, and cell cycle pathways. In conclusion, the present study indicates that EGCG can affect the methylation status and gene expression in the CAL‑27 cell line. Additionally, the changes in several important signaling pathways may reveal the antitumor mechanism of EGCG.
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Affiliation(s)
- Li-Li Chen
- Laboratory of Oral Biomedical Science and Translational Medicine, School of Stomatology, Tongji University, Shanghai 200072, P.R. China
| | - Wen-Fei Han
- Laboratory of Oral Biomedical Science and Translational Medicine, School of Stomatology, Tongji University, Shanghai 200072, P.R. China
| | - Ying Geng
- Laboratory of Oral Biomedical Science and Translational Medicine, School of Stomatology, Tongji University, Shanghai 200072, P.R. China
| | - Jian-Sheng Su
- Laboratory of Oral Biomedical Science and Translational Medicine, School of Stomatology, Tongji University, Shanghai 200072, P.R. China
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Yu L, Su J, Zou D, Mariano Z. The concentrations of IL-8 and IL-6 in gingival crevicular fluid during nickel-chromium alloy porcelain crown restoration. J Mater Sci Mater Med 2013; 24:1717-1722. [PMID: 23564008 DOI: 10.1007/s10856-013-4924-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2012] [Accepted: 04/01/2013] [Indexed: 06/02/2023]
Abstract
We explored gum irritation and cytotoxicity caused by nickel-chromium (Ni-Cr) alloy porcelain by interleukin-8 (IL-8), interleukin-6 (IL-6) and gingival crevicular fluid (GCF) volumes at different time points peri-crown restoration. This prospective study was conducted in 60 young adults. The total amount and concentrations of IL-8 and IL-6 per site, GCF volumes, and blood neutrophil counts were performed prior to and at 1 week, 3 months, and 6 months after Ni-Cr alloy-porcelain crown restoration. Thirty male and 30 female subjects, aged 20-35 years old were enrolled. The total amount and concentrations of IL-8 and IL-6 per site, GCF volumes increased after nickel-chromium (Ni-Cr) alloy-porcelain crown restoration, and reached its peak at the third month as the GCF volume increased by 52.20 %, the total amount and concentrations of IL-8 increased by 112.11 and 22.75 %; the total amount and concentrations of IL-6 increased by 77.66 and 17.17 % when compared to baseline. In particular, the increase of IL-8 concentration was found in female patients at 3 months after restoration; while the neutrophil count of the peripheral blood did not change significantly. The increase in the total amount and the concentrations of IL-8 and IL-6 and GCF volume may be related to the cytotoxicity induced by Ni-Cr alloy. The significant increase of IL-8 concentration in females indicates that more attention should be given to women during Ni-Cr alloy porcelain crown restoration.
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Affiliation(s)
- Lufeng Yu
- Department of Stomatology, The Sixth Affiliated People's Hospital of Shanghai Jiaotong University, No. 600 Yi Shan Road, Shanghai, 200233, China.
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Qiao GY, Shen QP, Su JS. [Study on cytotoxicity of three kinds of dental ceramic alloys on L929 mouse fibroblasts in vitro]. Shanghai Kou Qiang Yi Xue 2010; 19:72-76. [PMID: 20300698] [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: 05/29/2023]
Abstract
PURPOSE To investigate the cytotoxicity in vitro of three kinds of dental ceramic alloys on L929 mouse fibroblasts. METHODS CCK-8 assay was a quick method to study the cell relative proliferation rate or cytotoxicity. L929 mouse fibroblasts were used to detect the cell relative proliferation rate of the three kinds of dental ceramic alloys(NiCr,CoCr and golden alloys containing 58% of gold) by CCK-8 assay. The DNA damage of L929 mouse fibroblasts was determined by single cell gel electrophoresis(SCGE). The data was statistically analyzed with SAS 9.0 software package. RESULTS The relative growth rate induced by NiCr, CoCr and golden dental ceramic alloys was (75.9510+/-7.6244)%, (84.8920+/-8.2660)% and (88.5420+/-12.3611)%, respectively. NiCr ceramic alloys caused the most marked cytotoxicity(P<0.05), and there was no difference between CoCr ceramic alloys and 58% golden ceramic alloys(P>0.05). The cytotoxicity of the three kinds of metal ceramic alloys was all grade 1, i.e. mild cytotoxicity. The DNA damage of L929 mouse fibroblasts induced by NiCr ceramic alloys was most serious(P<0.05). There was no difference in the DNA damage between CoCr ceramic alloys and 58% golden ceramic alloys(P>0.05). CONCLUSIONS NiCr ceramic alloys can suppress the proliferation of the L929 mouse fibroblasts and promote DNA damage. While CoCr ceramic alloys which are similar to 58% golden ceramic alloys show less cytotoxicity than NiCr ceramic alloys. CoCr or 58% golden ceramic alloys should be used as crown and bridge for patients instead of NiCr ceramic alloy clinically.
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Affiliation(s)
- Guang-Yan Qiao
- Department of Prosthodontics, Shanghai Stomatological Disease Center. Shanghai 200001,China.
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Liu WC, Guo LY, Wang HB, Wu JH, Su JS. [The influence of thickness ratios on the fatigue behaviors of two kinds of dental ceramic]. Hua Xi Kou Qiang Yi Xue Za Zhi 2009; 27:92-99. [PMID: 19323406] [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: 05/27/2023]
Abstract
OBJECTIVE To investigate the intensity changes of different thickness ratios of Empress II glass ceramic and GI- II glass-infiltrated alumina ceramic before and after Hertzian contact cyclic fatigue. METHODS Disk-shaped specimens of different thickness ratios of Empress II glass ceramic and GI-II glass-infiltrated alumina ceramic were respectively fabricated. Hertzian contact technique was imposed on the specimens. Critical loads of the specimens before and after 10(5) cycles loading were recorded. RESULTS The average values of critical loads of all specimens reduced significantly after cycles loading (P < 0.05), and critical loads declined with diminishing thickness of the core ceramic. The critical load of GI-II glass-infiltrated alumina ceramic was significantly higher than Empress II glass ceramic before and after cycle loading(P < 0.05). CONCLUSION Cycle loading can reduce the strengths of the two kinds of dental ceramic, and the latter is better than the former in the resistance to fracture and cyclic fatigue. Critical loads of the two kinds of dental ceramic are mainly influenced by the core ceramic's strength and thickness.
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Affiliation(s)
- Wei-Cai Liu
- Dept. of Prosthodontics, School of Stomatology, Tongji University, Shanghai 200072, China
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Su JS, Guo LY, Liu WC. [Compared study of cyclic fatigue behaviors in two kinds of dental ceramic layers structures]. Hua Xi Kou Qiang Yi Xue Za Zhi 2007; 25:166-8, 172. [PMID: 17663343] [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: 05/16/2023]
Abstract
OBJECTIVE To compare the difference in strength degradation and morphology damage of two dental ceramic materials after Hertzian contact cyclic fatigue. METHODS Hertzian contact technique was used to investigate the response of Empress II glass ceramic and GI- II glass-infiltrated alumina ceramic to cyclic fatigue. Critical loads of specimens after different fatigue cycles were recorded. RESULTS For Empress II glass ceramic, critical load had significantly difference between specimens after 10(5) cycles loading. No significant difference of critical load was found in GI- II glass-infiltrated alumina ceramic after cycles loading. CONCLUSION GI- II glass-infiltrated alumina ceramic has better capability in resistance to cyclic loading. It may attribute to microstructure of material. Empress II glass ceramic shows a brittle damage model.
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Affiliation(s)
- Jian-Sheng Su
- Dept. of Prosthodontics, Oral Hospital of Tongdi University, Shanghai
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Su JS, Deng ZY, Shao L, Qiao GY, Wan SJ. [Study of DNA damage of buccal mucosal cells after wearing casting alloy crowns]. Hua Xi Kou Qiang Yi Xue Za Zhi 2006; 24:21-5. [PMID: 16541648] [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: 05/07/2023]
Abstract
OBJECTIVE To test the corrosion behavior of three kinds of dental casting alloys and to investigate the effect of the released metal ions on the DNA damage of dog buccal mucosal cells. METHODS Three kinds of frequently used dental casting alloys were used to make full crowns for dogs. The concentration of the released metal ions was measured after the restoration of 2 weeks, 1 month, 2 months and 3 months. The DNA damage of buccal mucosal cells was studied by the method of SCGE. RESULTS The metal ions released from NiCr and NiCrBe were detected in buccal mucosal cells while the amount of the ions released from noble alloy (gold 58%) was too small to be detected. The DNA damage of mucosal cells increased after restoration of NiCr and NiCrBe crowns. CONCLUSION The noble alloy (gold 58%) is most corrosion resistant of the three alloys and has good biocompatibility. The NiCr and NiCrBe are prone to corrode and have cytotoxicity to cells.
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Affiliation(s)
- Jian-Sheng Su
- Dept. of Prosthodontics, School of Dentistry, Tongji University, Shanghai 200072, China
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Abstract
In the present study six types of tricalcium phosphate ceramic were prepared and soaked in distilled water for different periods to investigate whether a surface apatite layer was formed on TCP ceramics or not. X-ray diffractometry (XRD) and Fourier-transformed infrared (FTIR) spectrometer were used to examine the changes in crystalline phases and functional groups of TCP ceramics for different soaking periods. Calcium and phosphate ions released from TCP ceramics during soaking were recorded by atomic absorption analysis and ion-coupled plasma. Results revealed that alphaTCP, alphaTCP/betaTCP mixture (alphabetaTCP) and betaTCP ceramic were gradually dissolved. There was no apatite layer formed on their surface after being immersed in distilled water for different durations of time. Mg-TCP ceramic, tricalcium phosphate doped with Mg ions, exhibited a lower dissolution rate than the other types of TCP ceramics. Apatite crystals were also not formed on the surface of Mg-TCP ceramic when immersed in distilled water. Tribasic calcium phosphate, prepared from wet precipitation method, was converted to betaTCP/HAP (HbetaTCP) or alphaTCP/betaTCP/HAP (HalphabetaTCP) crystalline composition at different sintering temperatures (1,150 degrees C and 1,300 degrees C). The surface apatite layer did not appear on HbetaTCP ceramic after soaking. We observed that petal-like apatite was formed on the HalphabetaTCP ceramic surface after being immersed for 2 weeks. alphaTCP phase of HalphabetaTCP ceramic was not directly converted to apatite during soaking. The surface apatite layer formed on the HalphabetaTCP ceramic surface was due to the precipitation of the calcium and phosphate ions released from alphaTCP dissolution. HAP, which existed in the structure of HalphabetaTCP ceramic, plays a role as apatite-precipitating seed to uptake calcium and phosphate ions. TCP ceramics which lacked alphaTCP and HAP content neither converted to apatite nor formed surface apatite on their surfaces during immersion.
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Affiliation(s)
- F H Lin
- Center of Biomedical Engineering, College of Medicine, National Taiwan University, Taipei
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Abstract
Deletion diagnostics are developed for identifying observations that influence the estimates of regression parameters and the mixture parameter in the families of relative risk functions for failure time data. The diagnostic for the regression parameters is a generalization of Cain and Lange's (1984, Biometrics 40, 493-499) measure of individual influence. The generalizations of martingale residuals, Schoenfeld's partial residuals (1982, Biometrika 69, 239-241), and score residuals by Therneau, Grambsch, and Fleming (1990, Biometrika 77, 147-160) are also obtained. The influence of some observations on regression parameters can be drastically modified as the mixture parameter changes, even for a very small change. In addition, adding or deleting some observations might result in choosing different models. The diagnostics are applied to a family proposed by Guerrero and Johnson (1982, Biometrika 69, 309-314). One illustrative example is presented.
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Affiliation(s)
- W H Wei
- Institute of Statistics, Academia Sinica, Taiwan, ROC.
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Wang LF, Ting CY, Lo CK, Su JS, Mickley LA, Fojo AT, Whang-Peng J, Hwang J. Identification of mutations at DNA topoisomerase I responsible for camptothecin resistance. Cancer Res 1997; 57:1516-22. [PMID: 9108454] [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: 02/04/2023]
Abstract
A camptothecin-resistant cell line that exhibits more than 600-fold resistance to camptothecin, designated CPT(R)-2000, was established from mutagen-treated A2780 ovarian cancer cells. CPT(R)-2000 cells also exhibit 3-fold resistance to a DNA minor groove-binding ligand Ho33342, a different class of mammalian DNA topoisomerase I inhibitors. However, CPT(R)-2000 cells exhibit no cross-resistance toward drugs such as Adriamycin, amsacrine, vinblastine, and 4'-dimethyl-epipodophyllotoxin. The mRNA, protein levels, and enzyme-specific activity of DNA topoisomerase I are relatively the same in parental and CPT(R)-2000 cells. However, unlike the DNA topoisomerase I activity of parental cells, which can be inhibited by camptothecin, that of CPT(R)-2000 cells cannot. In addition, parental cells after camptothecin treatment results in a decrease in the level of DNA topoisomerase I, whereas CPT(R)-2000 cells are insensitive to camptothecin treatment. These results suggested that the mechanism of camptothecin resistance is most likely due to a DNA topoisomerase I structural mutation. This notion is supported by DNA sequencing results confirming that DNA topoisomerase I of CPT(R)-2000 is mutated at amino acid residues Gly717 to Val and Thr729 to Ile. We also used the yeast system to examine the mutation(s) responsible for camptothecin resistance. Our results show that each single amino acid change results in partial resistance, and the double mutation gives a synergetic effect on camptothecin resistance. Because both mutation sites are near the catalytic active center, this observation raises the possibility that camptothecin may act at the vicinity of the catalytic active site of the enzyme-camptothecin-DNA complex.
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Affiliation(s)
- L F Wang
- Institute of Molecular Biology, Department of Biochemistry, Taipei Medical College, Taiwan, Republic of China
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Hwang DS, Chen YT, Su JS, Hu WH, Wang KY, Ting CT. Evidence of genetic heterogeneity of hypertrophic cardiomyopathy in eight Chinese patients. Zhonghua Yi Xue Za Zhi (Taipei) 1996; 57:315-21. [PMID: 8768378] [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: 02/02/2023]
Abstract
BACKGROUND The genetic basis causing hypertrophic cardiomyopathy (HCM) was found due to missense mutations in cardiac beta-myosin heavy chain (beta-MHC), cardiac troponin T and alpha-tropomyosin genes in certain affected families. However, most mutations and majority of the affected families were reported to be related to beta-MHC gene. Till now, 20 different missense mutations of beta-MHC gene identified in more than 40 independent families were distributed in exons 8, 9, 13, 14, 15, 16, 19, 20, 21 and 23. Therefore, we chose these 10 exons for screening. METHODS Eight probands with HCM and 1 normal control were included for screening. 32P-labeled PCR products of these 10 exons of beta-MHC gene were amplified from genomic DNA obtained from peripheral lymphocytes. PCR-DNA single strand conformation polymorphism (PCR-SSCP) analysis was performed using electrophoresis with polyacrylamide gels with and without 10% glycerol. Large amount copies of these 10 exons were also made from genomic DNA with PCR. Detection of sequencing variation of these exons was determined by the direct sequencing method with dideoxy chain termination method and 35S. RESULTS No abnormal extra bands were noted on PCR-SSCP analysis. Sequencing analysis showed no missense mutation in these probands. CONCLUSIONS Genetic heterogeneity of HCM is evident in Chinese patients with HCM.
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Affiliation(s)
- D S Hwang
- Department of Medicine, Taichung Veterans General Hospital, Taiwan, R.O.C
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Su JS, Zheng GR. [The changes of oral cavity tissues after immediate complete denture rehabilitation.]. Shanghai Kou Qiang Yi Xue 1995; 4:96-8. [PMID: 16538338] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Affiliation(s)
- J S Su
- Faculty of Stomatology, Shanghai Railway University. Shanghai 200072,China
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