1
|
Wu TJ, Tsai CL, Huang YH, Fan TY, Chen YP. Corrigendum to "Efficacy of machine learning assisted dental age assessment in local population" [Legal Med. 59 (2022) 102148]. Leg Med (Tokyo) 2023:102191. [PMID: 36610900 DOI: 10.1016/j.legalmed.2022.102191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- Te-Ju Wu
- Department of Craniofacial Orthodontics, Department of Dentistry, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Chia Ling Tsai
- Department of Pedodontics, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Yin-Hua Huang
- Department of Pediatrics, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Tzuo-Yau Fan
- Department of Artificial Intelligence Research and Development, Chang Gung Medical Technology Co., Ltd., Linkou, Taiwan; Center for Artificial Intelligence in Medicine, Chang Gung Memorial Hospital, Linkou, Taiwan
| | - Yueh-Peng Chen
- Center for Artificial Intelligence in Medicine, Chang Gung Memorial Hospital, Linkou, Taiwan.
| |
Collapse
|
2
|
Wu TJ, Tsai CL, Gao QZ, Chen YP, Kuo CF, Huang YH. The Application of Artificial-Intelligence-Assisted Dental Age Assessment in Children with Growth Delay. J Pers Med 2022; 12:jpm12071158. [PMID: 35887655 PMCID: PMC9322373 DOI: 10.3390/jpm12071158] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Revised: 07/11/2022] [Accepted: 07/15/2022] [Indexed: 12/30/2022] Open
Abstract
Background: This study aimed to reveal the efficacy of the artificial intelligence (AI)-assisted dental age (DA) assessment in identifying the characteristics of growth delay (GD) in children. Methods: The panoramic films matching the inclusion criteria were collected for the AI model training to establish the population-based DA standard. Subsequently, the DA of the validation dataset of the healthy children and the images of the GD children were assessed by both the conventional methods and the AI-assisted standards. The efficacy of all the studied modalities was compared by the paired sample t-test. Results: The AI-assisted standards can provide much more accurate chronological age (CA) predictions with mean errors of less than 0.05 years, while the traditional methods presented overestimated results in both genders. For the GD children, the convolutional neural network (CNN) revealed the delayed DA in GD children of both genders, while the machine learning models presented so only in the GD boys. Conclusion: The AI-assisted DA assessments help overcome the long-standing populational limitation observed in traditional methods. The image feature extraction of the CNN models provided the best efficacy to reveal the nature of delayed DA in GD children of both genders.
Collapse
Affiliation(s)
- Te-Ju Wu
- Department of Craniofacial Orthodontics, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung 833253, Taiwan;
| | - Chia-Ling Tsai
- Department of Pedodontics, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung 833253, Taiwan;
| | - Quan-Ze Gao
- Center for Artificial Intelligence in Medicine, Chang Gung Memorial Hospital, Taoyuan 333423, Taiwan; (Q.-Z.G.); (Y.-P.C.)
| | - Yueh-Peng Chen
- Center for Artificial Intelligence in Medicine, Chang Gung Memorial Hospital, Taoyuan 333423, Taiwan; (Q.-Z.G.); (Y.-P.C.)
| | - Chang-Fu Kuo
- Division of Rheumatology, Allergy and Immunology, Center for Artificial Intelligence in Medicine, Chang Gung Memorial Hospital, Linkou Medical Center, Taoyuan 333423, Taiwan;
| | - Ying-Hua Huang
- Department of Pediatrics, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung 833253, Taiwan
- Correspondence: ; Tel.: +886-7731-7123-8712
| |
Collapse
|
3
|
Gao WL, Lee YH, Tsai CY, Wu TJ, Lai JP, Lin SS, Chang YJ. One-Year Treatment Outcome of Profile Changes After Transcutaneous Maxillary Distraction Osteogenesis in Growing Children With Cleft Lip and Palate. Cleft Palate Craniofac J 2021; 59:299-306. [PMID: 33813912 DOI: 10.1177/10556656211005638] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
OBJECTIVE To evaluate the long-term stability of LeFort I osteotomy followed by distraction osteogenesis with a transcutaneous rigid external device for the treatment of severe maxillary hypoplasia in patients with cleft lip and palate. PATIENTS AND METHODS Nine patients with cleft lip and palate underwent rigid external distraction after a LeFort I osteotomy for maxillary advancement. Lateral cephalometric films were analyzed for assessment of treatment outcome and stability in 1 month, 6 months, and 1 year after distraction. RESULTS Significant maxillary advancement was observed in the horizontal direction, with the anterior nasal spine (ANS) distance of the maxilla increasing by an average of 20.5 ± 5.1 mm after distraction. The ANS relapse rates in 6 months and 1 year were 8.7% and 12.8%, respectively. The mean inclination of upper incisors to the palatal plane was almost unchanged (before: 109.8° ± 6.6°; after: 108.9° ± 7.5°). The movement ratios at the nasal tip/ANS, soft tissue A point/A point, and the upper vermilion border/upper incisor edge were 0.36:1, 0.72:1, and 0.83:1, respectively. CONCLUSION Considerable maxillary advancement was achieved with less change of incisors inclination after distraction. Moreover, the relapse rate after 1 year was minimal. The concave facial profile was improved as well as the facial balance and aesthetics.
Collapse
Affiliation(s)
- Wei-Ling Gao
- Department of Craniofacial Orthodontics, Department of Dentistry, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung
| | - Yi-Hao Lee
- Department of Craniofacial Orthodontics, Department of Dentistry, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung
| | - Chi-Yu Tsai
- Department of Craniofacial Orthodontics, Department of Dentistry, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung
| | - Te-Ju Wu
- Department of Craniofacial Orthodontics, Department of Dentistry, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung
| | - Jui-Pin Lai
- Department of Plastic and Reconstructive Surgery, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung
| | - Shiu-Shiung Lin
- Department of Craniofacial Orthodontics, Department of Dentistry, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung
| | - Yu-Jen Chang
- Department of Craniofacial Orthodontics, Department of Dentistry, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung
| |
Collapse
|
4
|
Wenzler E, Lee M, Wu TJ, Meyer KA, Shields RK, Nguyen MH, Clancy CJ, Humphries RM, Harrington AT. Performance of ceftazidime/avibactam susceptibility testing methods against clinically relevant Gram-negative organisms. J Antimicrob Chemother 2020; 74:633-638. [PMID: 30534964 DOI: 10.1093/jac/dky483] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Revised: 10/18/2018] [Accepted: 10/23/2018] [Indexed: 11/13/2022] Open
Abstract
OBJECTIVES To ensure the accuracy of susceptibility testing methods for ceftazidime/avibactam. METHODS The performances of the Etest (bioMérieux), 30/20 μg disc (Hardy diagnostics) and 10/4 μg disc (Mast Group) were evaluated against the reference broth microdilution (BMD) method for 102 clinically relevant Gram-negative organisms: 69 ceftazidime- and meropenem-resistant Klebsiella pneumoniae and 33 MDR non-K. pneumoniae. Essential and categorical agreement along with major and very major error rates were determined according to CLSI guidelines. RESULTS A total of 78% of isolates were susceptible to ceftazidime/avibactam. None of the three methods met the defined equivalency threshold against all 102 organisms. The Etest performed the best, with categorical agreement of 95% and major errors of 6.3%. Against the 69 ceftazidime- and meropenem-resistant K. pneumoniae, only the Etest and the 10/4 μg disc met the equivalency threshold. None of the three methods met equivalency for the 33 MDR isolates. There were no very major errors observed in any analysis. These results were pooled with those from a previous study of 74 carbapenem-resistant Enterobacteriaceae and data from the ceftazidime/avibactam new drug application to define optimal 30/20 μg disc thresholds using the error-rate bound model-based approaches of the diffusion breakpoint estimation testing software. This analysis identified a susceptibility threshold of ≤19 mm as optimal. CONCLUSIONS Our data indicate that the Etest is a suitable alternative to BMD for testing ceftazidime/avibactam against ceftazidime- and meropenem-resistant K. pneumoniae. The 30/20 μg discs overestimate resistance and may lead to the use of treatment regimens that are more toxic and less effective.
Collapse
Affiliation(s)
- E Wenzler
- College of Pharmacy, University of Illinois at Chicago, Chicago, IL, USA
| | - M Lee
- College of Pharmacy, University of Illinois at Chicago, Chicago, IL, USA
| | - T J Wu
- College of Pharmacy, University of Illinois at Chicago, Chicago, IL, USA
| | - K A Meyer
- College of Pharmacy, University of Illinois at Chicago, Chicago, IL, USA
| | - R K Shields
- Department of Medicine, University of Pittsburgh, Pittsburgh, PA, USA.,XDR Pathogen Laboratory, University of Pittsburgh, Pittsburgh, PA, USA
| | - M H Nguyen
- Department of Medicine, University of Pittsburgh, Pittsburgh, PA, USA.,XDR Pathogen Laboratory, University of Pittsburgh, Pittsburgh, PA, USA
| | - C J Clancy
- Department of Medicine, University of Pittsburgh, Pittsburgh, PA, USA.,XDR Pathogen Laboratory, University of Pittsburgh, Pittsburgh, PA, USA.,VA Pittsburgh Healthcare System, Pittsburgh, PA, USA
| | | | | |
Collapse
|
5
|
Chang YJ, Lai JP, Tsai CY, Wu TJ, Lin SS. Accuracy assessment of computer-aided three-dimensional simulation and navigation in orthognathic surgery (CASNOS). J Formos Med Assoc 2020; 119:701-711. [DOI: 10.1016/j.jfma.2019.09.017] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Revised: 09/19/2019] [Accepted: 09/27/2019] [Indexed: 11/27/2022] Open
|
6
|
Lee DJ, Kwon J, Kim YI, Wang X, Wu TJ, Lee YT, Kim S, Miguez P, Ko CC. Effect of pore size in bone regeneration using polydopamine-laced hydroxyapatite collagen calcium silicate scaffolds fabricated by 3D mould printing technology. Orthod Craniofac Res 2019; 22 Suppl 1:127-133. [PMID: 31074145 DOI: 10.1111/ocr.12261] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Accepted: 12/04/2018] [Indexed: 01/14/2023]
Abstract
OBJECTIVE The pore size of the scaffold is a critical factor in repairing large bone defect. Here, we investigated the potential of bone regeneration using novel nanocomposite polydopamine-laced hydroxyapatite collagen calcium silicate (HCCS-PDA) scaffolds with two different pore sizes, 250 and 500 μm. SAMPLES/SETTING A total of 12 male Sprague-Dawley rats were implanted with HCCS-PDA scaffold with pore size of either 250 or 500 μm into surgically created critical-sized defect (CSD). METHODS HCCS-PDA scaffolds were fabricated using mould printing technique. The effect of pore size on mechanical strength of the scaffolds was assessed by compression testing. After seeding with rat mesenchymal stem cells (rMSCs), the scaffolds were implanted, and new bone formation was evaluated using microCT and histomorphometric analysis after 8 weeks. RESULTS MicroCT and histology analysis demonstrated restricted peripheral new bone formation in either dural or periosteal side and limited new bone formation in the 250 μm pore scaffold. Conversely, the 500-μm pore scaffold showed more penetration of new bone into the scaffold and greater bone regeneration in the rat CSD. CONCLUSION Based on our results, which demonstrated improved new bone formation in 500 μm pores scaffold, we can conclude that effective scaffold pore size that induces osteointegration and bone regeneration is around 500 μm for HCCS-PDA nanocomposite scaffold.
Collapse
Affiliation(s)
- Dong Joon Lee
- Oral and Craniofacial Health Sciences Research, School of Dentistry, University of North Carolina, Chapel Hill, North Carolina
| | - Jane Kwon
- Oral and Craniofacial Health Sciences Research, School of Dentistry, University of North Carolina, Chapel Hill, North Carolina
| | - Yong-Il Kim
- Oral and Craniofacial Health Sciences Research, School of Dentistry, University of North Carolina, Chapel Hill, North Carolina.,Department of Orthodontics, School of Dentistry, Pusan National University, Yangsan, Republic of Korea
| | - Xiaoyu Wang
- Oral and Craniofacial Health Sciences Research, School of Dentistry, University of North Carolina, Chapel Hill, North Carolina
| | - Te-Ju Wu
- Oral and Craniofacial Health Sciences Research, School of Dentistry, University of North Carolina, Chapel Hill, North Carolina.,Department of Orthodontics, Chang Gung Memorial Hospital, Kaohsiung, Taiwan
| | - Yan-Ting Lee
- Oral and Craniofacial Health Sciences Research, School of Dentistry, University of North Carolina, Chapel Hill, North Carolina
| | - Steven Kim
- Oral and Craniofacial Health Sciences Research, School of Dentistry, University of North Carolina, Chapel Hill, North Carolina
| | - Patricia Miguez
- Oral and Craniofacial Health Sciences Research, School of Dentistry, University of North Carolina, Chapel Hill, North Carolina
| | - Ching-Chang Ko
- Oral and Craniofacial Health Sciences Research, School of Dentistry, University of North Carolina, Chapel Hill, North Carolina.,Department of Orthodontics, School of Dentistry, University of North Carolina, Chapel Hill, North Carolina
| |
Collapse
|
7
|
Hsieh YC, Liao YC, Li CH, Lin JC, Weng CJ, Lin CC, Lo CP, Huang KC, Huang JL, Lin CH, Wu TJ, Sheu WH. P5644Hypoglycemic episodes increase the risk of ventricular arrhythmias and sudden cardiac arrest in patients with type 2 diabetes - a nationwide cohort study. Eur Heart J 2019. [DOI: 10.1093/eurheartj/ehz746.0587] [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] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Background
Hypoglycemic episode (HE) increases the risk of cardiovascular mortality. The impact of HE on the risk of sudden death remains unclear. We hypothesized that HE increases the risks of ventricular arrhythmia (VA) and sudden cardiac arrest (SCA), and that anti-diabetic agents (ADAs) causing hypoglycemia also increase the risks of VA and SCA.
Methods
Patients aged ≥20 years with newly diagnosed diabetes were identified from the Taiwan National Insurance Database. HE was defined as the presentation of hypoglycemic coma or specified/unspecified hypoglycemia. For control group, we included diabetic patients without HE, and they were frequency-matched to the HE group at a 4:1 ratio. The primary outcome was the occurrence of any event of VA (including ventricular tachycardia and fibrillation) and SCA during the defined follow-up periods. Multivariate Cox hazards regression model was used to evaluate the hazard ratio (HR) for VA or SCA.
Results
A total of 54,303 diabetic patients were screened with 1,037 of them in the HE group, and 4,148 in the control group. During a mean follow-up period of 3.3±2.5 years, 29 VA/SCA events had occurred. Compared to the control group, the HE group had a higher incidence of VA/SCA (adjusted HR: 2.42, p=0.04). Diabetic patients medicated with insulin for glycemic control increased the risk of VA/SCA compared to those without insulin (adjusted HR: 3.05, p=0.01).
Kaplan-Meier survival curves
Conclusions
HEs in patients with diabetes increased the risks of VA and SCA compared to those without. Their use of insulin also independently increased the risk of VA/SCA.
Collapse
Affiliation(s)
- Y C Hsieh
- Taichung Veterans General Hospital, Cardiovascular Center, Taichung, Taiwan
| | - Y C Liao
- Taichung Veterans General Hospital, Cardiovascular Center, Taichung, Taiwan
| | - C H Li
- Taichung Veterans General Hospital, Cardiovascular Center, Taichung, Taiwan
| | - J C Lin
- Chiayi Branch, Taichung Veterans General Hospital, Department of Internal Medicine, Chiayi, Taiwan
| | - C J Weng
- Taichung Veterans General Hospital, Cardiovascular Center, Taichung, Taiwan
| | - C C Lin
- Taichung Veterans General Hospital, Department of Medical Research, Taichung, Taiwan
| | - C P Lo
- Providence University, Department of Financial Engineering, Taichung, Taiwan
| | - K C Huang
- Providence University, Department of Financial Engineering, Taichung, Taiwan
| | - J L Huang
- Taichung Veterans General Hospital, Cardiovascular Center, Taichung, Taiwan
| | - C H Lin
- Taichung Veterans General Hospital, Department of Medical Research, Taichung, Taiwan
| | - T J Wu
- Taichung Veterans General Hospital, Cardiovascular Center, Taichung, Taiwan
| | - W H Sheu
- Taichung Veterans General Hospital, Division of Endocrinology and Metabolism, Department of Medicine, Taichung, Taiwan
| |
Collapse
|
8
|
Lin WW, Lee MF, Lin SJ, Wu TJ. P6204Oral vaccination of Lactococcus lactis expressing Ling Zhi 8 protein prevents nonalcoholic fatty liver and early atherogenesis in cholesterol-fed rabbits. Eur Heart J 2019. [DOI: 10.1093/eurheartj/ehz746.0809] [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] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Background
Atherosclerosis is an inflammatory disease characterized by lipid deposits in the subendothelial space leading to severe inflammation. Nonalcoholic fatty liver disease (NAFLD) shares several risk factors with atherosclerosis. Epidemiology studies have indicated that NAFLD may be an independent risk factor for atherosclerosis. Anti-inflammation therapy by inhibiting IL-1β led to a significantly lower cardiovascular event rate in recent clinical trial (CANTOS trial). Ling Zhi 8 (LZ8) is an immunomodulatory protein that possesses a broad range of pharmacological properties, including anti-inflammatory activities.
Methods and findings
In this study, we developed an oral vaccination of Lactococcus lactis expressing LZ8 protein in a nisin-controlled gene expression system and investigated its anti-inflammation properties. Experimental rabbits received commercial rabbit chow supplemented with 2% cholesterol for 5 weeks and recombinant LZ8 L. lactis vaccine once a day on weekdays. The expression of IL-1β in the aorta (Figure A) was significantly suppressed after LZ8 vaccination. Moreover, in hematoxylin and eosin staining of the aorta, the intima-medial thickness was decreased, and foam cells were significantly reduced in the sub-endothelial space (Figure C). LZ8 also inhibited the expression of IL-1β in the liver (Figure B), decreased fat droplet deposits and infiltration of inflammatory cells (Figure D), and improved liver function by decreasing liver enzymes.
Figure 1
Conclusions
Our results suggest that LZ8 could be used as a therapeutic tool to improve both atherosclerosis and NAFLD due to its anti-inflammatory effect.
Acknowledgement/Funding
TCVGH-1067317C, TCVGH-1063108C
Collapse
Affiliation(s)
- W W Lin
- Taichung Veterans General Hospital, cardiovascular center, Taichung, Taiwan
| | - M F Lee
- Taichung Veterans General Hospital, medical research center, Taichung, Taiwan
| | - S J Lin
- Chung Shan Medical University Hospital, School of Medical Laboratory and Biotechnology, Taichung, Taiwan
| | - T J Wu
- Taichung Veterans General Hospital, cardiovascular center, Taichung, Taiwan
| |
Collapse
|
9
|
Hsieh YC, Li CH, Liao YC, Lin JC, Weng CJ, Lin SF, Huang JL, Wu TJ. P2564Levosimendan shortens action potential duration, decreases alternans threshold and prevents ventricular arrhythmia during therapeutic hypothermia in isolated rabbit hearts. Eur Heart J 2019. [DOI: 10.1093/eurheartj/ehz748.0892] [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] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Background
Therapeutic hypothermia (TH) increases the susceptibility to ventricular arrhythmias (VA) by prolonging action potential duration (APD) and facilitating arrhythmogenic spatially discordant alternans (SDA). The calcium sensitizer levosimendan has been reported to shorten APD by enhancing ATP-sensitive K current. We hypothesize that levosimendan might shorten the already prolonged APD during TH, decreasing SDA threshold, and prevent the occurrence of VA.
Methods
Langendorff-perfused isolated rabbit hearts were subjected to 15-min TH (30°C) followed by 30-min treatment with levosimendan (0.5 μM, n=9) or vehicle (n=8). Using an optical mapping system, epicardial APD was evaluated by S1 pacing. SDA threshold was defined as the longest pacing cycle length (PCL) that induced SDA phenomenon. Ventricular fibrillation (VF) inducibility was evaluated by burst pacing for 30 s using the shortest PCL that achieved 1:1 ventricular capture.
Results
Levosimendan shortened the ventricular APD (at PCL 300 ms, from 229±9 ms to 211±18 ms, p=0.02) and decrease the SDA threshold (from 327±88 ms to 311±68 ms, p=0.001) during TH. The VF inducibility was decreased by levosimendan from 39±30% at 30°C to 14±12% after levosimendan infusion. In control hearts, the APD (p=0.75), SDA threshold (p=ns) and VF inducibility (p=0.12) were not changed by vehicle during TH.
Conclusions
Levosimendan protects the hearts against VA during TH by shortening APD and decreasing SDA threshold. Enhancing ATP-sensitive K current with levosimendan might be a novel approach to prevent VA during TH.
Collapse
Affiliation(s)
- Y C Hsieh
- Taichung Veterans General Hospital, Taichung, Taiwan
| | - C H Li
- Taichung Veterans General Hospital, Taichung, Taiwan
| | - Y C Liao
- Taichung Veterans General Hospital, Taichung, Taiwan
| | - J C Lin
- Chiayi Branch, Taichung Veterans General Hospital, Department of Internal Medicine, Chiayi, Taiwan
| | - C J Weng
- Chiayi Branch, Taichung Veterans General Hospital, Department of Internal Medicine, Chiayi, Taiwan
| | - S F Lin
- National Chiao Tung University, Institute of Biomedical Engineering, Hsinchu, Taiwan
| | - J L Huang
- Taichung Veterans General Hospital, Taichung, Taiwan
| | - T J Wu
- Taichung Veterans General Hospital, Taichung, Taiwan
| |
Collapse
|
10
|
Ahn MS, Shin SM, Yamaguchi T, Maki K, Wu TJ, Ko CC, Kim YI. Relationship between the maxillofacial skeletal pattern and the morphology of the mandibular symphysis: Structural equation modeling. Korean J Orthod 2019; 49:170-180. [PMID: 31149607 PMCID: PMC6533179 DOI: 10.4041/kjod.2019.49.3.170] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [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: 10/11/2018] [Revised: 12/04/2018] [Accepted: 12/19/2018] [Indexed: 11/10/2022] Open
Abstract
Objective The purpose of this study was to investigate the relationship between the facial skeletal patterns and the shape of the mandibular symphysis in adults with malocclusion by using a structural equation model (SEM). Methods Ninety adults who had malocclusion and had records of facial skeletal measurements performed using cone-beam computed tomography were selected for this study. The skeletal measurements were classified into three groups (vertical, anteroposterior, and transverse). Cross-sectional images of the mandibular symphysis were analyzed using generalized Procrustes and principal component (PC) analyses. A SEM was constructed after the factors were extracted via factor analysis. Results Two factors were extracted from the transverse, vertical, and anteroposterior skeletal measurements. Latent variables were extracted for each factor. PC1, PC2, and PC3 were selected to analyze the variations of the mandibular symphyseal shape. The SEM was constructed using the skeletal variables, PCs, and latent variables. The SEM showed that the vertical latent variable exerted the most influence on the mandibular symphyseal shape. Conclusions The relationship between the skeletal pattern and the mandibular symphysis was analyzed using a SEM, which showed that the vertical facial skeletal pattern had the highest effect on the shape of the mandibular symphysis.
Collapse
Affiliation(s)
- Mi So Ahn
- Department of Orthodontics, Dental Research Institute, Pusan National University Dental Hospital, Yangsan, Korea
| | - Sang Min Shin
- Department of Management Information Systems, College of Business, Dong-A University, Busan, Korea
| | - Tetsutaro Yamaguchi
- Department of Orthodontics, School of Dentistry, Showa University, Tokyo, Japan
| | - Koutaro Maki
- Department of Orthodontics, School of Dentistry, Showa University, Tokyo, Japan
| | - Te-Ju Wu
- Department of Orthodontics, Chang Gung Memorial Hospital, Kaohsiung, Taiwan
| | - Ching-Chang Ko
- Department of Orthodontics, School of Dentistry, University of North Carolina at Chapel Hill, NC, USA
| | - Yong-Il Kim
- Department of Orthodontics, Dental Research Institute, Pusan National University Dental Hospital, Yangsan, Korea.,Institute of Translational Dental Sciences, School of Dentistry, Pusan National University, Busan, Korea
| |
Collapse
|
11
|
Trivellin G, Stigliano A, Wu TJ, Stratakis C. SAT-032 In Vitro Characterization Of GPR101 Transcriptional Regulation. J Endocr Soc 2019. [PMCID: PMC6551756 DOI: 10.1210/js.2019-sat-032] [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] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Background: X-linked acrogigantism (X-LAG) is a novel syndrome of early childhood-onset gigantism caused by duplications of GPR101, a gene that is strongly upregulated in the pituitary adenomas (PAs) of the patients. Aim: To study the human GPR101 promoter. Methods:GPR101 promoter annotation was carried out in silico using the Genomatix and MPromDb softwares and by querying specific tracks in the UCSC Genome Browser. The identified sequences were cloned into reporter vectors and transiently transfected into HEK293 cells. Promoter activity was assessed by luciferase assays and quantitative PCR (qPCR) under normal growth conditions and after treatments with forskolin (10 μM, 6h) and β-estradiol (E2, 100 nM, 24h). Putative binding sites for cAMP responsive elements (CREs) were functionally evaluated by mutagenesis studies. GPR101-specific primers were used for an open chromatin assay. Results:In silico characterization of the GPR101 promoter revealed two putative promoter regions, each overlapping a CpG island. The proximal sequence partially extends into the coding sequence (CDS), is marked by a promoter-specific histone modification (H3K4me3), and harbors one CRE; the distal sequence is located 2 Kb upstream of the start codon and harbors three CREs. In vitro reporter assays confirmed that both sequences were functional (3-fold change over mock for both, P<0.001) and that activation of the cAMP signaling pathway further stimulates GPR101 transcription only via the distal promoter (1.8-fold change over basal, P<0.05). Mutation of two CREs within the distal promoter significantly reduced basal transcription rates and forskolin stimulation could not restore normal expression. Treatment with E2 inhibited basal transcription rates of both promoter sequences (0.3 and 0.4-fold change, respectively, P<0.01). qPCR in cells transfected with a promoterless vector containing only GPR101 CDS showed strong GPR101 levels, suggesting that sequences within the CDS can drive its transcription. However, mutation of a CDS-located CRE did not affect basal or forskolin-stimulated transcription. No endogenous GPR101 transcripts were detected in HEK293 cells. We determined that the lack of correlation between reporter activities and endogenous expression was due to the location of the GPR101 locus in a heterochromatin region. Conclusions: These results show that GPR101 is a gene endowed with a complex promoter that likely allow varying levels of expression as required. Unraveling the transcriptional regulation of GPR101 is an important step towards understanding how this gene is regulated during physiological (development) and pathological (X-LAG) states. The finding that cAMP (a pathway commonly deregulated in PAs) stimulates GPR101 expression and that mutations disrupting CREs negatively impact this expression warrants screening of GPR101 promoter in patients with PAs.
Collapse
Affiliation(s)
| | | | - TJ Wu
- Uniformed Services University of the Health Sciences, Bethesda, MD, United States
| | | |
Collapse
|
12
|
Ahn MS, Shin SM, Choi YS, Wu TJ, Ko CC, Yamaguchi T, Maki K, Kim YI. Analysis of the relationship between the morphology of the palate and facial skeletal patterns in Class III malocclusion using structural equation modelling. Orthod Craniofac Res 2019; 22:87-92. [PMID: 30633439 DOI: 10.1111/ocr.12283] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Revised: 12/28/2018] [Accepted: 01/04/2019] [Indexed: 11/29/2022]
Abstract
INTRODUCTION The present study investigated the relationship between facial skeletal patterns and morphology of the palate in adult patients with Class III malocclusion using structural equation modelling (SEM). SETTING AND SAMPLE POPULATION One hundred cone beam computed tomography images of Class III adults were evaluated for skeletal measurements. MATERIALS AND METHODS The skeletal measurements were classified into the vertical, anteroposterior and transverse group based on factor analysis. 3D scanning model of the maxilla was analysed by Generalized procrustes analysis (GPA) and principal component analysis (PCA). Structural equation modelling was used to analyse relationship among the skeletal and morphometric factors. RESULTS According to the factor analysis, latent variables were extracted by each skeletal variable. First principal component (PC1) and PC2 of palatal morphology were used to analyse relationship with skeletal variables. As results of the structural equation model, the transverse latent variable had the most influence on PC1, followed by vertical and anteroposterior variables. This result means that as the facial width increases, the palate becomes narrower, deeper and longer. CONCLUSIONS The relationship between the skeletal pattern with Class III malocclusion and palatal morphology was analysed through SEM. The transverse facial skeletal pattern showed the highest correlation with PC1 of palatal morphology.
Collapse
Affiliation(s)
- Mi So Ahn
- Department of Orthodontics, Dental research institute, Pusan National University Dental Hospital, Yangsan, Korea
| | - Sang Min Shin
- Department of Management Information Systems, College of Business, Dong-A University, Busan, Korea
| | - Yong-Seok Choi
- Department of Statistics, College of Natural Sciences, Pusan National University, Busan, Korea
| | - Te-Ju Wu
- Department of Orthodontics, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan
| | - Ching-Chang Ko
- Department of Orthodontics, School of Dentistry, University of North Carolina at Chapel Hill, North Carolina
| | - Tetsutaro Yamaguchi
- Department of Orthodontics, School of Dentistry, Showa University, Tokyo, Japan
| | - Koutaro Maki
- Department of Orthodontics, School of Dentistry, Showa University, Tokyo, Japan
| | - Yong-Il Kim
- Department of Orthodontics, Dental research institute, Pusan National University Dental Hospital, Yangsan, Korea.,Institute of Translational dental science, School of Dentistry, Pusan National University, Busan, Korea
| |
Collapse
|
13
|
Tsai CY, Chang YJ, Wu TJ, Lai JP, Chen TY, Lin SS. Blood loss and operative time associated with orthognathic surgery utilizing a novel navigation system in cleft lip and palate patients. J Formos Med Assoc 2019; 118:588-599. [PMID: 30630700 DOI: 10.1016/j.jfma.2018.12.011] [Citation(s) in RCA: 6] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2018] [Revised: 09/15/2018] [Accepted: 12/17/2018] [Indexed: 11/18/2022] Open
Abstract
PURPOSE This retrospective study evaluated the volume of blood loss and operative time associated with management of nongrowing patients with cleft lip and palate (CLP) using bimaxillary orthognathic surgery (OGS) designed by a three-dimensional (3D) computer-assisted simulation and navigation for orthognathic surgery (CASNOS) system. METHODS This study included 53 skeletal Class III nongrowing patients with unilateral CLP who underwent bimaxillary OGS using either the CASNOS protocol (n = 30) or the traditional two-dimensional (2D) method (n = 23). The skeletal parameters of jaw-bone components, the levels of hemoglobin (Hb) and hematocrit (Hct) were measured before and after surgery. The estimated blood loss and actual blood loss (ABL) were also calculated. RESULTS The two groups did not differ significantly with regard to the demographic parameters (age, gender, and body mass index), the preoperative skeletal parameters and surgical changes of jaw-bone components. The mean ABL of the CASNOS group was significantly lower than that of the control group (915.6 ± 280.5 vs. 1204.9 ± 201.0 ml, p < 0.001), and the changes in Hb and Hct level also followed a similar pattern in both groups. The mean operative time was significantly shorter in the CASNOS group compared with the control group (384.2 ± 48.5 vs. 469.0 ± 94.9 min, p < 0.001). CONCLUSION This study demonstrated that the application of the 3D CASNOS approach in OGS for the management of complicated Class III nongrowing patients with CLP significantly shortened the operative time and reduced ABL in comparison with the traditional 2D methods.
Collapse
Affiliation(s)
- Chi-Yu Tsai
- Department of Craniofacial Orthodontics, Department of Dentistry, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Yu-Jen Chang
- Department of Craniofacial Orthodontics, Department of Dentistry, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Te-Ju Wu
- Department of Craniofacial Orthodontics, Department of Dentistry, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Jui-Pin Lai
- Department of Plastic and Reconstructive Surgery, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Tzu-Ying Chen
- Department of Plastic and Reconstructive Surgery, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Shiu-Shiung Lin
- Department of Craniofacial Orthodontics, Department of Dentistry, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan.
| |
Collapse
|
14
|
Ahn MS, Shin SM, Wu TJ, Lee DJ, Ko CC, Chung CJ, Kim YI. Correlation between the cross-sectional morphology of the mandible and the three-dimensional facial skeletal pattern: A structural equation modeling approach. Angle Orthod 2018; 89:78-86. [PMID: 30080126 DOI: 10.2319/122117-879.1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
OBJECTIVE To clarify the relationship between the cross-sectional morphology of the mandible and vertical, transverse, and anteroposterior facial skeletal patterns using statistical shape analysis and structural equation modeling (SEM). MATERIALS AND METHODS We used 150 cone beam computed tomography (CBCT) images to obtain three-dimensional (3D) facial landmarks and cross-sectional images of the mandible. The morphology of the inner and outer cortices of the mandible was analyzed using statistical shape analysis, including generalized Procrustes analysis and principal component analysis (PCA). Factor analysis was performed to determine factors pertaining to the skeletal measurements and shape variations for the inner and outer cortices, following which a structural equation model was constructed. RESULTS Using factor analysis, characteristics of the vertical, transverse, and anteroposterior facial skeletal patterns were determined. PCA of the cross-sectional morphology of the mandible revealed 70% of the cumulative proportion by PC1 and PC2 after generalized Procrustes superimpositions. SEM showed complex relationships between the facial skeletal patterns and variations in the cross-sectional morphology of the mandibular cortices. The influence of the transverse factors on the outer cortex as a latent variable was relatively significant ( P = .057). However, the influence of the vertical factors on the outer and inner cortices was not significant. CONCLUSIONS The transverse skeletal pattern is associated with the morphology of the outer cortex of the mandible.
Collapse
|
15
|
Zou XL, Ma PL, Wu TJ. [The application of procalcitonin in differential diagnosis of sepsis/septic shock]. Zhonghua Nei Ke Za Zhi 2018; 57:605-606. [PMID: 30060336 DOI: 10.3760/cma.j.issn.0578-1426.2018.08.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
|
16
|
Rudolph LM, Bentley GE, Calandra RS, Paredes AH, Tesone M, Wu TJ, Micevych PE. Peripheral and Central Mechanisms Involved in the Hormonal Control of Male and Female Reproduction. J Neuroendocrinol 2016; 28:10.1111/jne.12405. [PMID: 27329133 PMCID: PMC5146987 DOI: 10.1111/jne.12405] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/14/2016] [Revised: 05/25/2016] [Accepted: 06/20/2016] [Indexed: 12/18/2022]
Abstract
Reproduction involves the integration of hormonal signals acting across multiple systems to generate a synchronised physiological output. A critical component of reproduction is the luteinising hormone (LH) surge, which is mediated by oestradiol (E2 ) and neuroprogesterone interacting to stimulate kisspeptin release in the rostral periventricular nucleus of the third ventricle in rats. Recent evidence indicates the involvement of both classical and membrane E2 and progesterone signalling in this pathway. A metabolite of gonadotrophin-releasing hormone (GnRH), GnRH-(1-5), has been shown to stimulate GnRH expression and secretion, and has a role in the regulation of lordosis. Additionally, gonadotrophin release-inhibitory hormone (GnIH) projects to and influences the activity of GnRH neurones in birds. Stress-induced changes in GnIH have been shown to alter breeding behaviour in birds, demonstrating another mechanism for the molecular control of reproduction. Peripherally, paracrine and autocrine actions within the gonad have been suggested as therapeutic targets for infertility in both males and females. Dysfunction of testicular prostaglandin synthesis is a possible cause of idiopathic male infertility. Indeed, local production of melatonin and corticotrophin-releasing hormone could influence spermatogenesis via immune pathways in the gonad. In females, vascular endothelial growth factor A has been implicated in an angiogenic process that mediates development of the corpus luteum and thus fertility via the Notch signalling pathway. Age-induced decreases in fertility involve ovarian kisspeptin and its regulation of ovarian sympathetic innervation. Finally, morphological changes in the arcuate nucleus of the hypothalamus influence female sexual receptivity in rats. The processes mediating these morphological changes have been shown to involve the rapid effects of E2 controlling synaptogenesis in this hypothalamic nucleus. In summary, this review highlights new research in these areas, focusing on recent findings concerning the molecular mechanisms involved in the central and peripheral hormonal control of reproduction.
Collapse
Affiliation(s)
- L M Rudolph
- Department of Neurobiology, Laboratory of Neuroendocrinology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - G E Bentley
- Department of Integrative Biology, and Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA, USA
| | - R S Calandra
- Instituto de Biología y Medicina Experimental (IBYME-CONICET), Buenos Aires, Argentina
| | - A H Paredes
- Laboratory of Neurobiochemistry, Faculty of Chemistry and Pharmaceutical Sciences, Universidad de Chile, Independencia, Santiago, Chile
| | - M Tesone
- Instituto de Biología y Medicina Experimental (IBYME-CONICET), Buenos Aires, Argentina
| | - T J Wu
- Department of Obstetrics and Gynecology, Center for Neuroscience and Regenerative Medicine, Uniformed Services University, Bethesda, MD, USA
| | - P E Micevych
- Department of Neurobiology, Laboratory of Neuroendocrinology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| |
Collapse
|
17
|
Larco DO, Williams M, Schmidt L, Sabel N, Lange J, Woller MJ, Wu TJ. Autoshortloop feedback regulation of pulsatile gonadotropin-releasing hormone (GnRH) secretion by its metabolite, GnRH-(1-5). Endocrine 2015; 49:470-8. [PMID: 25516463 DOI: 10.1007/s12020-014-0492-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/04/2014] [Accepted: 11/24/2014] [Indexed: 12/28/2022]
Abstract
Given the central role of the decapeptide gonadotropin-releasing hormone (GnRH) in reproductive function, our long-term objective is to delineate the underlying mechanism regulating these reproductive processes. The outcome of GnRH secretion is in part dependent on the proteolytic metabolism of this decapeptide. In contrast to the belief that the metabolism of GnRH serves only as a degradative process that removes excess GnRH, we have shown that a metabolite of the decapeptide, GnRH-(1-5), can directly regulate GnRH gene expression and reproductive behavior. To further characterize the effect of GnRH-(1-5) on GnRH neuronal function, we determined whether GnRH-(1-5) can directly regulate GnRH secretion and pulsatility using an in vitro perifusion system. We compared the effect of GnRH-(1-5) on GnRH secretion in the immortalized GnRH neuron (GT1-7 cell line), whole rat hypothalamic explant, and enzymatically dispersed rat hypothalamic cells. Tissue preparations were perifused continuously for 9 h during which a 3-h challenge with GnRH-(1-5) was administered (4-6 h). The results show that treatment with GnRH-(1-5) increased (p < 0.05) the mean GnRH secretion and the amplitude of the pulses but not the pulse frequency. The present study supports the notion that GnRH-(1-5) is functionally capable of regulating the reproductive neuroendocrine system.
Collapse
Affiliation(s)
- Darwin O Larco
- Department of Obstetrics and Gynecology, Uniformed Services University of the Health Sciences, 4301 Jones Bridge Road, Bethesda, MD, 20814, USA
| | | | | | | | | | | | | |
Collapse
|
18
|
Keil MF, Briassoulis G, Nesterova M, Miraftab N, Gokarn N, Wu TJ, Stratakis CA. Threat bias in mice with inactivating mutations of Prkar1a. Neuroscience 2013; 241:206-14. [PMID: 23531435 DOI: 10.1016/j.neuroscience.2013.03.027] [Citation(s) in RCA: 5] [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] [Received: 12/13/2012] [Revised: 03/13/2013] [Accepted: 03/14/2013] [Indexed: 01/18/2023]
Abstract
Anxiety disorders are associated with abnormalities in the neural processing of threat-related stimuli. However, the neurobiological mechanisms underlying threat bias in anxiety are not well understood. We recently reported that a Prkar1a heterozygote (Prkar1a(+/-)) mouse with haploinsufficiency for the main regulatory subunit (R1α) of protein kinase A (PKA) exhibits an anxiety-like phenotype associated with increased cAMP signaling in the amygdala. Prkar1a(+/-) mice provide a novel model to test the direct effect of altered PKA expression and subsequent anxiety-like behavioral phenotype on the response to threat. We hypothesized that Prkar1a(+/-)mice would exhibit a bias in threat detection since increased amygdala activity during emotional stimuli is associated with a maladaptive response. We measured behavior and PKA activity in brain areas after exposure to predator or control odor exposure in male Prkar1a(+/-) and wild-type (WT) littermates. Indeed, there were significant differences in the behavioral response to threat detection; WT mice showed the expected response of decrease in exploratory behavior during predator vs. control odor exposure, while Prkar1a(+/-) mice did not alter their behavior between conditions. Basal and total PKA activity was independently associated with genotype, with an interaction between genotype and threat condition. Prkar1a(+/-) mice had higher PKA activity in amygdala and ventromedial hypothalamus in response to predator odor. In contrast, WT mice had higher PKA activity in amygdala and orbitofrontal cortex after exposure to control odor. Dysregulated PKA activity in the amygdala-prefrontal cortex circuitry in Prkar1a(+/-) mice is associated with behavioral phenotype of anxiety and a bias for threat. This is likely related to a failure to inhibit the amydgala response, which is an effect of the genotype. These results suggest that the alteration in PKA signaling in Prkar1a(+/-) mice is not ubiquitous in the brain; tissue-specific effects of the cAMP/PKA pathway are related to threat detection and fear sensitization.
Collapse
Affiliation(s)
- M F Keil
- Section on Endocrinology and Genetics, Program in Developmental Endocrinology and Genetics, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health, Bethesda, MD 20892, USA.
| | | | | | | | | | | | | |
Collapse
|
19
|
Strack AM, Carballo-Jane E, Wang SP, Xue J, Ping X, McNamara LA, Thankappan A, Price O, Wolff M, Wu TJ, Kawka D, Mariano M, Burton C, Chang CH, Chen J, Menke J, Luell S, Zycband EI, Tong X, Raubertas R, Sparrow CP, Hubbard B, Woods J, O'Neill G, Waters MG, Sitlani A. Nicotinic acid and DP1 blockade: studies in mouse models of atherosclerosis. J Lipid Res 2012; 54:177-88. [PMID: 23103473 DOI: 10.1194/jlr.m031344] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
The use of nicotinic acid to treat dyslipidemia is limited by induction of a "flushing" response, mediated in part by the interaction of prostaglandin D(2) (PGD(2)) with its G-protein coupled receptor, DP1 (Ptgdr). The impact of DP1 blockade (genetic or pharmacologic) was assessed in experimental murine models of atherosclerosis. In Ptgdr(-/-)ApoE(-/-) mice versus ApoE(-/-) mice, both fed a high-fat diet, aortic cholesterol content was modestly higher (1.3- to 1.5-fold, P < 0.05) in Ptgdr(-/-)ApoE(-/-) mice at 16 and 24 weeks of age, but not at 32 weeks. In multiple ApoE(-/-) mouse studies, a DP1-specific antagonist, L-655, generally had a neutral to beneficial effect on aortic lipids in the presence or absence of nicotinic acid treatment. In a separate study, a modest increase in some atherosclerotic measures was observed with L-655 treatment in Ldlr(-/-) mice fed a high-fat diet for 8 weeks; however, this effect was not sustained for 16 or 24 weeks. In the same study, treatment with nicotinic acid alone generally decreased plasma and/or aortic lipids, and addition of L-655 did not negate those beneficial effects. These studies demonstrate that inhibition of DP1, with or without nicotinic acid treatment, does not lead to consistent or sustained effects on plaque burden in mouse atherosclerotic models.
Collapse
Affiliation(s)
- Alison M Strack
- Atherosclerosis, Merck Sharp & Dohme Corp., Rahway, NJ 07065, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
20
|
|
21
|
Abstract
Reproduction is an event that requires the coordination of peripheral organs with the nervous system to ensure that the internal and external environments are optimal for successful procreation of the species. This is accomplished by the hypothalamic-pituitary-gonadal axis that coordinates reproductive behavior with ovulation. The primary signal from the central nervous system is gonadotropin-releasing hormone (GnRH), which modulates the activity of anterior pituitary gonadotropes regulating follicle stimulating hormone (FSH) and luteinizing hormone (LH) release. As ovarian follicles develop they release estradiol, which negatively regulates further release of GnRH and FSH. As estradiol concentrations peak they trigger the surge release of GnRH, which leads to LH release inducing ovulation. Release of GnRH within the central nervous system helps modulate reproductive behaviors providing a node at which control of reproduction is regulated. To address these issues, this review focuses on several critical questions. How is the HPG axis regulated in species with different reproductive strategies? What internal and external conditions modulate the synthesis and release of GnRH? How does GnRH modulate reproductive behavior within the hypothalamus? How does disease shift the activity of the HPG axis?
Collapse
Affiliation(s)
- A Christensen
- Department of Neurobiology, University of California, Los Angeles, CA 90095, USA.
| | | | | | | | | | | | | |
Collapse
|
22
|
Zhou HP, Yi DH, Yu SQ, Sun GC, Cui Q, Zhu HL, Liu JC, Zhang JZ, Wu TJ. Administration of donor-derived mesenchymal stem cells can prolong the survival of rat cardiac allograft. Transplant Proc 2007; 38:3046-51. [PMID: 17112896 DOI: 10.1016/j.transproceed.2006.10.002] [Citation(s) in RCA: 105] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2006] [Indexed: 12/11/2022]
Abstract
BACKGROUND Mesenchymal stem cells (MSCs) are multipotent adult elements that have recently been shown to have profound immunomodulatory effects both in vitro and in vivo. Herein we have examined the impact of intravenous infusion of donor MSCs on the survival of transplanted hearts in a rat allograft model. METHODS Recipient Fisher344 rats were transplanted with hearts from inbred Wistar rats. Wistar rat MSCs were infused via the tail vein at designated intervals. In vitro mixed lymphocyte reaction (MLR) and cell-mediated lympholysis (CML) assays were performed to assess whether MSCs downregulated T-cell responses in vivo. Real-time polymerase chain reaction (PCR) was used to analyze the Th1/Th2 balance in MSC-treated and control groups. RESULTS The MSCs cultured in vitro exhibited multipotential for differentiation. Survival of the allografts was markedly prolonged by administration of MSCs compared with the controls, namely mean survivals of 12.4 vs 6.4 days, respectively. Real-time PCR showed a shift in the Th1/Th2 balance toward Th2. By MLR and CML assays, untreated control rats showed greater alloreactivity than did MSC-treated rats. CONCLUSION Our results indicated that MSCs suppressed allogeneic T-cell responses both in vitro and in vivo. Intravenous administration of MSCs prolonged the survival of transplanted hearts, possibly by induction of allograft tolerance through changing the Th1/Th2 balance.
Collapse
Affiliation(s)
- H P Zhou
- Department of Cardiovascular Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an City, Shannxi Province, China.
| | | | | | | | | | | | | | | | | |
Collapse
|
23
|
Abstract
In the female rat, ovulation is preceded by a marked increase in the release of the decapeptide, LHRH, culminating in a preovulatory LH surge, which coincides with a period of sexual receptivity. The decapeptide, LHRH, is processed by a zinc metalloendopeptidase EC 3.4.24.15 (EP24.15) that cleaves the hormone at the Tyr(5)-Gly(6) bond. We have previously reported that the autoregulation of LHRH gene expression can also be mediated by its metabolite, LHRH-(1-5). Given the central function of LHRH in reproduction and reproductive behavior, we examined the role of the metabolite, LHRH-(1-5), in mediation of LHRH-facilitated reproductive behavior. Intracerebroventricular administration of LHRH-(1-5) facilitated sexual behavior responses, similar to those facilitated by the decapeptide LHRH, in ovariectomized estradiol-primed female rats. Furthermore, immunoneutralization of EP24.15 resulted in the inhibition of the LHRH-facilitated lordosis but had no inhibitory effects on LHRH-(1-5)-facilitated lordosis. The LHRH antagonist, Antide, was capable of inhibiting LHRH-facilitated lordosis, without affecting LHRH-(1-5)-facilitated lordosis. Collectively, these results suggest a role for LHRH metabolites in the facilitation of female receptive behavior in rats.
Collapse
Affiliation(s)
- T J Wu
- Department of Obstetrics and Gynecology, Uniformed Services University of the Health Sciences, Bethesda, Maryland 20814, USA.
| | | | | | | |
Collapse
|
24
|
Eddington DO, Baldwin EL, Segars JH, Wu TJ. Estrogen effects on the expression of Brx in the brain and pituitary of the mouse. Brain Res Bull 2006; 69:447-51. [PMID: 16624676 DOI: 10.1016/j.brainresbull.2006.02.021] [Citation(s) in RCA: 2] [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] [Received: 12/30/2005] [Accepted: 02/15/2006] [Indexed: 11/24/2022]
Abstract
A member of the Dbl family of oncoproteins was discovered in breast cancer tissue extracts. This novel protein, designated Brx, contains an estrogen-receptor binding motif and is highly expressed in hormone-responsive breast tissue. Due to its ability to augment ligand-dependent activation of estrogen receptors, we analyzed the expression of Brx in the adult mouse brain and pituitary. Results indicated that Brx was expressed in specific regions of the brain and pituitary. Furthermore, the results indicate that differences exist in both brain and pituitary tissue of male and female mice with greater expression in the female. However, estrogen did not influence Brx expression in ovariectomized mice. The anatomical studies support a role for Brx in its association with the estrogen receptor and that Brx may be involved in neuronal and pituitary function in a sexually dimorphic manner.
Collapse
Affiliation(s)
- David O Eddington
- Program in Molecular and Cellular Biology, Uniformed Services University of Health Sciences, Bethesda, MD 20814, USA
| | | | | | | |
Collapse
|
25
|
Wu TJ, Mani SK, Glucksman MJ, Roberts JL. Stimulation of luteinizing hormone-releasing hormone (LHRH) gene expression in GT1-7 cells by its metabolite, LHRH-(1-5). Endocrinology 2005; 146:280-6. [PMID: 15486221 DOI: 10.1210/en.2004-0560] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Given the central role of the decapeptide LHRH in reproduction and reproductive behavior, it is important to focus on delineating the possible effects of this gene and its products in the regulation of hormone-dependent reproductive processes. In the female, ovulation is preceded by a marked increase in LHRH release; the increase in LHRH release culminates in a preovulatory LH surge, which coincides with a period of sexual receptivity. In contrast to the belief that the proteolytic metabolism of LHRH serves only as a degradative process that removes excess LHRH and attenuates signal transduction through the LHRH receptor, we hypothesized that a metabolite of the decapeptide, LHRH-(1-5), can directly regulate LHRH neuronal function. This study demonstrates the ability of LHRH-(1-5) peptide to regulate LHRH gene expression in the LHRH neuronal cell line, the GT(1-7) cell. The results show that LHRH-(1-5) stimulated LHRH gene expression at the posttranscriptional level. In contrast to the LHRH suppression of its own gene expression, the coadministration of LHRH with the metalloendopeptidase, EC 3.4.24.15, an endopeptidase known to cleave LHRH to form LHRH(1-5), shows a reversal of effect, a stimulation of LHRH gene expression. Finally, the effect of LHRH-(1-5) on LHRH gene expression appears to be mediated by the calcium/calmodulin-dependent protein kinase. The present study supports the hypothesis that the physiological metabolite of LHRH, LHRH-(1-5), is functionally capable of regulating the reproductive neuroendocrine system.
Collapse
Affiliation(s)
- T J Wu
- Department of Obstetrics and Gynecology, Uniformed Services University of the Health Sciences, Bethesda, Maryland 20814, USA.
| | | | | | | |
Collapse
|
26
|
Gore AC, Wu TJ, Oung T, Lee JB, Woller MJ. A novel mechanism for endocrine-disrupting effects of polychlorinated biphenyls: direct effects on gonadotropin-releasing hormone neurones. J Neuroendocrinol 2002; 14:814-23. [PMID: 12372006 DOI: 10.1046/j.1365-2826.2002.00845.x] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Polychlorinated biphenyls (PCBs) cause abnormal development and physiology of the reproductive system. We hypothesized that these effects may be mediated, at least in part, by neuroendocrine cells in the hypothalamus that integrate inputs to and outputs from the central nervous system and reproductive systems. The effects of two PCB mixtures, Aroclor 1221 and Aroclor 1254, were tested on the hypothalamic GT1-7 cells, which synthesize and secrete the key hypothalamic hormone, gonadotropin-releasing hormone (GnRH). GT1-7 cells were treated for 24 h in dose-response experiments and GnRH gene expression and release were quantified. Aroclor 1221 was stimulatory to GnRH gene expression, particularly at post-transcriptional levels (GnRH cytoplasmic mRNA), and increased GnRH peptide levels, suggesting a post-translational regulation of GnRH biosynthesis. It also caused a qualitative increase in GT1-7 neurite outgrowth and cell confluency. Aroclor 1254 had very different effects from Aroclor 1221. It inhibited GnRH nuclear mRNA levels at high dosages, and stimulated GnRH mRNA at low doses, suggesting a post-transcriptional mechanism of regulation. Aroclor 1254 did not alter GnRH peptide levels. Qualitatively, Aroclor 1254 caused a retraction of GT1-7 cell processes and neurotoxicity at high dosages. In order to gauge the involvement of the oestrogen receptor in these responses, the oestrogen receptor antagonist, ICI 182,780 (ICI) was coadministered in other studies with the PCBs. While effects of Aroclor 1221 on GnRH gene expression were not blocked by ICI, its effects on GnRH peptide levels were blocked by ICI, indicating that some but not all of the effects of Aroclor 1221 are mediated by the classical oestrogen receptor alpha and/or beta. The inhibitory effects of Aroclor 1254 on GnRH gene expression were not prevented by ICI, although ICI itself had stimulatory effects on GnRH gene expression that were blocked by cotreatment with Aroclor 1254. These results demonstrate a novel mechanism for effects of the two PCBs directly on GnRH gene expression, and indicate a hypothalamic level for endocrine disruption by these environmental toxicants.
Collapse
Affiliation(s)
- A C Gore
- Kastor Neurobiology of Aging Laboratories, Fishberg Research Center for Neurobiology, and Brookdale Department of Geriatrics and Adult Development, Mount Sinai School of Medicine, New York, NY 10029, USA.
| | | | | | | | | |
Collapse
|
27
|
Abstract
Based on extensive evaluation of the existing evidence and consensus development, there are new recommendations in the Neonatal Resuscitation Program (NRP) guidelines 2000. These guidelines are described along with a brief review of the supporting evidence. The goal is to establish a framework for practice of neonatal resuscitation with a more scientific, evidence-based approach.
Collapse
Affiliation(s)
- T J Wu
- Department of Pediatrics, University of Alabama at Birmingham, 35233, USA
| | | |
Collapse
|
28
|
Wu TJ, Kim YH, Yashima M, Athill CA, Ting CT, Karagueuzian HS, Chen PS. Progressive action potential duration shortening and the conversion from atrial flutter to atrial fibrillation in the isolated canine right atrium. J Am Coll Cardiol 2001; 38:1757-65. [PMID: 11704392 DOI: 10.1016/s0735-1097(01)01606-0] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
OBJECTIVES We sought to evaluate the effects of progressive shortening of the action potential duration (APD) on atrial wave front stability. BACKGROUND The mechanisms of conversion from atrial flutter to atrial fibrillation (AF) are unclear. METHODS Isolated canine right atria were perfused with 1 to 5 micromol/l of acetylcholine (ACh). We mapped the endocardium by using 477 bipolar electrodes and simultaneously recorded transmembrane potentials from the epicardium. The APD(90) was measured during regular pacing (S(1)) with cycle lengths of 300 ms. Atrial arrhythmia was induced by a premature stimulus (S(2)). RESULTS At baseline, only short runs of repetitive beats (<10 cycles) were induced. After shortening the APD(90) from 124 +/- 15 ms to 72 +/- 9 ms (p < 0.01) with 1 to 2.5 micromol/l of ACh, S(2) pacing induced single, stable and stationary re-entrant wave fronts (307 +/- 277 cycles). They either anchored to pectinate muscles (5 tissues) or used pectinate muscles as part of the re-entry (4 tissues). When ACh was raised to 2.5 to 5 micromol/l, the APD(90) was further shortened to 40 +/- 12 ms (p < 0.01); S(2) pacing induced in vitro AF by two different mechanisms. In most episodes (n = 13), AF was characterized by rapid, nonstationary re-entry and multiple wave breaks. In three episodes with APD(90) <30 ms, AF was characterized by rapid, multiple, asynchronous, but stationary wave fronts. CONCLUSIONS Progressive APD shortening modulates atrial wave front stability and converts atrial flutter to AF by two mechanisms: 1) detachment of stationary re-entry from the pectinate muscle and the generation of multiple wave breaks; and 2) formation of multiple, isolated, stationary wave fronts with different activation cycle lengths.
Collapse
Affiliation(s)
- T J Wu
- Division of Cardiology, Department of Medicine, Taichung Veterans General Hospital and Institute of Clinical Medicine, Cardiovascular Research Center, National Yang-Ming University School of Medicine, Taipei, Taiwan.
| | | | | | | | | | | | | |
Collapse
|
29
|
Abstract
AIMS To assess the factors associated with successful discontinuation of insulin therapy after diabetic ketoacidosis (DKA) in adult patients. METHODS Patients (>or= 18 years) attending the Endocrine and Metabolism Clinic at a major hospital in southern Taiwan were recruited. After recovery from the acute stage, those with no contraindications to oral antidiabetic agents, with adequate beta cell reserve, and with no antiglutamic acid decarboxylase (GAD) antibody were treated with oral agents. RESULTS Sixty-six patients (38 males, 28 females, aged 18-76 years) were included, and 21 qualified for treatment with oral agents. These 21 patients were older at diagnosis of diabetes (45.5 +/- 14.0 vs. 40.0 +/- 13.8 years, P = 0.047), had shorter diabetes duration (median 0 vs. 5.5 months, P = 0.040), higher BMI (median 23.4 vs. 19.5 kg/m2, P < 0.001), higher serum osmolality during DKA (352.1 +/- 40.7 vs. 318.0 +/- 16.4 mmol/kg, P = 0.005), and lower insulin dose following recovery (median 0.49 vs. 0.83 unit/kg/d, P < 0.001) than those patients that had to continue insulin therapy. Thirteen patients (8 males, 5 females; 62%) successfully discontinued insulin for at least one year without recurrence of DKA. Multiple logistic regression analyses showed that BMI >or= 25 kg/m2 (adjusted relative risk (ARR) 8.85, 95% CI 1.05, 8.39), diabetes onset age >or= 40 years (ARR 8.08, 95% CI 1.16, 6.95), and undiagnosed diabetes before DKA (ARR 8.90, 95% CI 1.19, 7.51) were significant factors associated with successful discontinuation of insulin therapy. CONCLUSION We identified three independent clinical factors associated with successful discontinuation of insulin therapy after DKA.
Collapse
Affiliation(s)
- E Hsin Yu
- Division of Endocrinology and Metabolism, Department of Internal Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan, Republic of China
| | | | | |
Collapse
|
30
|
Ashton WT, Sisco RM, Kieczykowski GR, Yang YT, Yudkovitz JB, Cui J, Mount GR, Ren RN, Wu TJ, Shen X, Lyons KA, Mao AH, Carlin JR, Karanam BV, Vincent SH, Cheng K, Goulet MT. Orally bioavailable, indole-based nonpeptide GnRH receptor antagonists with high potency and functional activity. Bioorg Med Chem Lett 2001; 11:2597-602. [PMID: 11551758 DOI: 10.1016/s0960-894x(01)00512-1] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [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: 11/20/2022]
Abstract
Stereospecific introduction of a methyl group to the indole-3-side chain enhanced activity in our tryptamine-derived series of GnRH receptor antagonists. Further improvements were achieved by variation of the bicyclic amino moiety of the tertiary amide and by adjustment of the tether length to a pyridine or pyridone terminus. These modifications culminated in analogue 24, which had oral activity in a rat model and acceptable oral bioavailability and half-life in dogs and monkeys.
Collapse
Affiliation(s)
- W T Ashton
- Department of Medicinal Chemistry, Merck Research Laboratories, PO Box 2000, NJ 07065-0900, Rahway, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
31
|
Abstract
In molecular biology, the issue of quantifying the similarity between two biological sequences is very important. Past research has shown that word-based search tools are computationally efficient and can find some new functional similarities or dissimilarities invisible to other algorithms like FASTA. Recently, under the independent model of base composition, Wu, Burke, and Davison (1997, Biometrics 53, 1431 1439) characterized a family of word-based dissimilarity measures that defined distance between two sequences by simultaneously comparing the frequencies of all subsequences of n adjacent letters (i.e., n-words) in the two sequences. Specifically, they introduced the use of Mahalanobis distance and standardized Euclidean distance into the study of DNA sequence dissimilarity. They showed that both distances had better sensitivity and selectivity than the commonly used Euclidean distance. The purpose of this article is to extend Mahalanobis and standardized Euclidean distances to Markov chain models of base composition. In addition, a new dissimilarity measure based on Kullback-Leibler discrepancy between frequencies of all n-words in the two sequences is introduced. Applications to real data demonstrate that Kullback-Leibler discrepancy gives a better performance than Euclidean distance. Moreover, under a Markov chain model of order kQ for base composition, where kQ is the estimated order based on the query sequence, standardized Euclidean distance performs very well. Under such a model, it performs as well as Mahalanobis distance and better than Kullback-Leibler discrepancy and Euclidean distance. Since standardized Euclidean distance is drastically faster to compute than Mahalanobis distance, in a usual workstation/PC computing environment, the use of standardized Euclidean distance under the Markov chain model of order kQ of base composition is generally recommended. However, if the user is very concerned with computational efficiency, then the use of Kullback-Leibler discrepancy, which can be computed as fast as Euclidean distance, is recommended. This can significantly enhance the current technology in comparing large datasets of DNA sequences.
Collapse
Affiliation(s)
- T J Wu
- Department of Statistics, National Cheng-King University, Tainan, Taiwan.
| | | | | |
Collapse
|
32
|
Abstract
This case report describes a patient with drug refractory paroxysmal atrial fibrillation (PAF). Rapid focal activations with multiple sharp spikes were continuously identified inside the left superior pulmonary vein (PV) during sustained AF. Among seven episodes of AF, cessation of rapid focal activations coincided with the conversion of AF to flutter (n = 4) or immediate AF termination (n = 3). Guided by sharp spikes in the PV, abrupt termination of AF occurred during radiofrequency energy application. Conclusively, rapid focal activations inside the PV are critical in AF maintenance. Cessation of these rapid focal activations underlies the mechanism by which AF converts to flutter.
Collapse
Affiliation(s)
- T J Wu
- Division of Cardiology, Department of Medicine, Taichung Veterans General Hospital, 160, Section 3, Chung-Kang Road, Taichung, Taiwan.
| | | | | |
Collapse
|
33
|
Yang SC, Wu TJ. Fournier's gangrene--Taiwan experience. Zhonghua Yi Xue Za Zhi (Taipei) 2001; 64:239-43. [PMID: 11458762] [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: 02/20/2023]
Abstract
BACKGROUND Synergistic necrotizing fascitis of the scrotum, penis and perianal region was first described by Fournier in 1883. If not recognized early, this infectious process will extend along the fascia plane to the lower abdominal and back regions, causing severe morbidity and even mortality. METHODS The records of 8 patients diagnosed of Fournier's gangrene were reviewed between 1988 and 2000. The sex, age, etiology, associated diseases, bacteriological studies and treatments were analyzed. RESULTS The 8 patients were all males, age ranging from 42 to 78 years old, with average 55.1 years. Six patients were due to perianal abscess, one patient was a complication of hemorroidectomy, and one patient had traumatic injury of scrotum. Six patients had poor controlled diabetes mellitus, and there were two patients with cirrhosis of the liver and hepatoma, respectively. Even with aggressive treatments, two patients died; the other 6 recovered completely. The mortality rate was 25%. CONCLUSIONS Fournier's gangrene is a not common but life-threatening disease which needs radical debridement and effective antibiotics to control the infection and early reconstruction with skin graft and myocutaneous flaps. Mortality is usually due to delayed diagnosis.
Collapse
Affiliation(s)
- S C Yang
- Division of Plastic Surgery, Taipei Municipal Chung-Hsiao Hospital, 87, Tung-Teh Road, Nankang, Taipei 115, Taiwan.
| | | |
Collapse
|
34
|
Koo GC, Huang C, Camacho R, Trainor C, Blake JT, Sirotina-Meisher A, Schleim KD, Wu TJ, Cheng K, Nargund R, McKissick G. Immune enhancing effect of a growth hormone secretagogue. J Immunol 2001; 166:4195-201. [PMID: 11238671 DOI: 10.4049/jimmunol.166.6.4195] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Growth hormone (GH) has been known to enhance immune responses, whether directly or through the insulin like growth factor-1, induced by GH. Recently a nonpeptidyl small m.w. compound, a GH secretagogue (GHS), was found to induce the production of GH by the pituitary gland. In this study, we examined the effect of GHS in immunological functions of 5- to 6-wk-old and 16- to 24-month-old mice. In young mice, we observed a significant increase in PBLs, but T and B cell-proliferative responses were not consistently enhanced. The old mice, treated with GHS for 3 wk, did not show increases in peripheral lymphocytes, but they exhibited a statistically significant increase in thymic cellularity and differentiation. When inoculated with a transplantable lymphoma cell line, EL4, the treated old mice showed statistically significant resistance to the initiation of tumors and the subsequent metastases. Generation of CTL to EL4 cells was also enhanced in the treated mice, suggesting that GHS has a considerable immune enhancing effect, particularly in the old mice. We have also found that GHS promoted better thymic engraftment in bone marrow transplant of SCID mice. We found more cycling cells in the spleens of treated mice, suggesting that GHS may exert its immune enhancing effect by promoting cell division in lymphoid cells. These observations ascribe to GHS a novel therapy possible for aging, AIDS, and transplant individuals, whose immune functions are compromised.
Collapse
Affiliation(s)
- G C Koo
- Department of Immunology Research, Merck Research Laboratories, Rahway, NJ 07065, USA.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
35
|
Abstract
Angiogenesis is of vital importance during the development and progression of solid tumors. Vascular endothelial growth factor (VEGF) is a major regulator of angiogenesis and could be produced by some cancer cells. To investigate the clinical relevance of VEGF in the tumorigenesis of human thyroid, an immunohistochemical study was performed on archival materials of follicular adenomas (n = 13), Hürthle cell adenomas (n = 6), papillary carcinomas (n = 76), follicular carcinomas (n = 12), Hürthle cell carcinomas (n = 2), and anaplastic carcinomas (n = 8). Patterns of VEGF expression were analyzed in relation to histologic subtypes of thyroid tumors and were correlated to biologic indicators of papillary carcinoma. All papillary carcinomas and Hürthle cell neoplasms revealed a strong, diffuse staining reaction, whereas anaplastic carcinoma usually exhibited weak and infrequent immunoreactivity. VEGF levels were usually higher in follicular adenomas than in follicular carcinomas. With regard to prognostic value, VEGF expression did not correlate with tumor size, extent of invasion, or scores on the AGES system (i.e., patient age, tumor size, histologic grade, tumor extent, distant metastasis) or the MACIS system (i.e., metastasis, age, completeness of resection, invasion, tumor size) for papillary carcinomas (p > 0.05, respectively). The results of the current study indicate that VEGF may play a role in the development of human thyroid cancer. Determination of the angiogenic phenotype may have limited prognostic value for patients with papillary carcinoma.
Collapse
Affiliation(s)
- S M Huang
- Department of Surgery, Tzu Chi College of Medicine, Hualien, Taiwan 970, Republic of China
| | | | | | | |
Collapse
|
36
|
Wu TJ, Ong JJ, Chang CM, Doshi RN, Yashima M, Huang HL, Fishbein MC, Ting CT, Karagueuzian HS, Chen PS. Pulmonary veins and ligament of Marshall as sources of rapid activations in a canine model of sustained atrial fibrillation. Circulation 2001; 103:1157-63. [PMID: 11222481 DOI: 10.1161/01.cir.103.8.1157] [Citation(s) in RCA: 113] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND In dogs, chronic rapid pacing may result in sustained atrial fibrillation (AF). However, activation patterns in pacing-induced sustained AF are unclear. METHODS AND RESULTS We induced sustained AF (>48 hours) in 6 dogs by rapid pacing for 139+/-84 days. We then performed computerized atrial epicardial mappings and recorded the activations in the ligament of Marshall (LOM) and the pulmonary veins (PVs). During AF, mean activation cycle length in the right atrial free wall (126+/-17 ms) was significantly longer than that in the left atrial free wall (96+/-5 ms, P:=0.006). In addition, mean activation cycle length in the left atrial free wall was significantly longer than that in the LOM (84+/-5 ms, P:<0.001), the left inferior PV (81+/-4 ms, P:=0.001), and the left superior PV (85+/-7 ms, P:=0.003). Similarly, the dominant frequency was highest in the LOM and the PVs (range 11.2 to 13.3 Hz), followed by the left and right atria (P:<0.001). In all dogs studied, rapid and complicated electrograms were consistently observed at the LOM and the PVs. During AF, both wandering wavelets and organized reentry were present. There were more wave fronts in the left atrium than in the right atrium (P:<0.001). CONCLUSIONS In chronic pacing-induced sustained AF, the LOM and the PVs are the sources of rapid activations. The mechanism by which the left atrium activates faster and has more wave fronts than the right atrium may relate to the fact that the left atrium is closer to the sources of rapid activations.
Collapse
Affiliation(s)
- T J Wu
- Division of Cardiology, Department of Medicine, Taichung Veterans General Hospital and Institute of Clinical Medicine, National Yang-Ming University School of Medicine, Taipei, Taiwan
| | | | | | | | | | | | | | | | | | | |
Collapse
|
37
|
Chang CM, Wu TJ, Zhou S, Doshi RN, Lee MH, Ohara T, Fishbein MC, Karagueuzian HS, Chen PS, Chen LS. Nerve sprouting and sympathetic hyperinnervation in a canine model of atrial fibrillation produced by prolonged right atrial pacing. Circulation 2001; 103:22-5. [PMID: 11136680 DOI: 10.1161/01.cir.103.1.22] [Citation(s) in RCA: 149] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Long-term rapid atrial pacing may result in atrial fibrillation (AF) in dogs. Whether there is histological evidence for neural remodeling is unclear. METHOD AND RESULTS We performed rapid right atrial pacing in 6 dogs for 111+/-76 days to induce sustained AF. Tissues from 6 healthy dogs were used as controls. Immunocytochemical staining of cardiac nerves was performed using anti-growth-associated protein 43 (GAP43) and anti-tyrosine hydroxylase (TH) antibodies. In dogs with AF, the density of GAP43-positive and TH-positive nerves in the right atrium was 470+/-406 and 231+/-126 per mm(2), respectively, which was significantly (P:<0.001) higher than the nerve density in control tissues (25+/-32 and 88+/-40 per mm(2), respectively). The density of GAP43-positive and TH-positive nerves in the atrial septum was 317+/-36 and 155+/-85 per mm(2), respectively, and was significantly (P:<0.001) higher than the nerve density in control tissues (9+/-13 and 30+/-7 per mm(2), respectively). Similarly, the density of GAP43-positive and TH-positive nerves in the left atrium of dogs with AF was 119+/-61 and 91+/-40 per mm(2), respectively, which was significantly (P:<0.001) higher than the nerve density in control tissues (10+/-15 and 38+/-39 per mm(2), respectively). Furthermore, in dogs with AF, the right atrium had a significantly higher nerve density than the left atrium. Microscopic examinations revealed an inhomogeneous distribution of cardiac nerves within each sampling site. CONCLUSIONS Significant nerve sprouting and sympathetic hyperinnervation are present in a canine model of sustained AF produced by prolonged right atrial pacing. The magnitude of nerve sprouting and hyperinnervation was higher in the right atrium than in the left atrium.
Collapse
Affiliation(s)
- C M Chang
- Division of Cardiology, Department of Medicine, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | | | | | | | | | | | | | | | | | | |
Collapse
|
38
|
Tsai HY, Wu TJ, Chen HJ, Lu CW. Chylus-like urine as a complication of percutaneous hyperalimentation catheter in an infant: report of one case. Acta Paediatr Taiwan 2001; 42:46-8. [PMID: 11270186] [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: 02/19/2023]
Abstract
A very low-birth-weight neonate developed chylus-like urine after receiving parenteral nutrition (PN) via percutaneous central venous catheters (CVC) for 7 weeks. A perirenal fluid collection could be seen under sonography. This kind of complication has not been described in literature. After withdrawing the CVC for 5 cm, the urine cleared up. For patients under prolonged PN via CVC and repeated change dressing of the CVC, close monitoring and regular evaluation of the position of the catheter tip are warranted.
Collapse
Affiliation(s)
- H Y Tsai
- Department of Pediatrics, Provincial Taoyuan Hospital, 1492, Chong Shan Road, Taoyuan 330, Taiwan
| | | | | | | |
Collapse
|
39
|
Valderrábano M, Kim YH, Yashima M, Wu TJ, Karagueuzian HS, Chen PS. Obstacle-induced transition from ventricular fibrillation to tachycardia in isolated swine right ventricles: insights into the transition dynamics and implications for the critical mass. J Am Coll Cardiol 2000; 36:2000-8. [PMID: 11092677 DOI: 10.1016/s0735-1097(00)00941-4] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
OBJECTIVES The study was done to test the hypothesis that an artificial anatomical obstacle prevents the maintenance of ventricular fibrillation (VF) by stabilizing reentrant wavefronts (RWF) and increases the critical mass (CM) of myocardium required to sustain VF. BACKGROUND Artificial obstacles can anchor RWF in simulated models of VF. Whether an artificial obstacle affects multiple-wavelet VF in real tissue is unclear. METHODS The endocardial surfaces of seven isolated, perfused swine right ventricles were mapped using a plaque of 477 bipolar electrodes with 1.6-mm resolution. An 8-mm hole was punched in the tissue. The CM was reached by tissue mass reductions, at which VF converted to periodic activity (ventricular tachycardia, VT). RESULTS After the creation of the obstacle, the VF cycle length increased from 71.6+/-18.4 ms to 87.5+/-13.0 ms (p<0.05). The obstacle, together with the papillary muscle, facilitated the transition from VF to VT by serving as attachment sites for the RWF. When one RWF attaches to the obstacle and another attaches to the papillary muscle, it may result in stable VT with figure-eight patterns. The CM for VF in the presence of an 8-mm hole (28.7+/-3.8 g) was higher than in the control group (swine right ventricles without holes, 24.0+/-3.4 g, p<0.05). CONCLUSIONS An artificial anatomical obstacle induces slowing and regularization of VF, impairs the persistence of VF as judged by an increase of the CM, and can convert VF to VT by serving as an attachment site to reentrant excitation.
Collapse
Affiliation(s)
- M Valderrábano
- Department of Medicine, Cedars-Sinai Medical Center, and UCLA School of Medicine, Los Angeles, California, USA
| | | | | | | | | | | |
Collapse
|
40
|
Abstract
Diabetes mellitus (DM) in adults is a global health problem, although its prevalence varies widely between different populations and the rate has generally increased worldwide. In Taiwan, the mortality rate from DM has almost doubled over the past 10 years. The prevalence of DM in Taiwan was established between 1985 and 1996 and the rates were between 4.9 and 9.2%. The prevalence of impaired glucose tolerance (IGT) was 15.5% (men 15% and women 15.9%). The prevalence of DM and IGT increased significantly with age for both genders. The significant factors associated with newly diagnosed DM were age, BMI, family history of DM, systolic blood pressure (hypertension), physical activity and serum triglyceride levels. The prevalence of large vessel disease (LVD) in DM and non-diabetic subjects were 20.0 and 12.9%, respectively. Among diabetics, 15.8% had ischemic heart disease (IHD), 1.7% leg vessel disease (leg VD), and 2.5% stroke. In non-diabetics, the prevalence of the aforementioned macroangiopathies were 11.5, 0.2 and 1.2%, respectively. The diabetics had a significantly higher prevalence of macrovascular disease than non-diabetic subjects. The most significantly associated with the LVD was serum cholesterol levels. Serum cholesterol and HbA1(c) were significantly associated with the development of IHD. Cigarette smoking and female gender were significantly associated with the leg VD. The prevalence of diabetic retinopathy (DR) was 35.0%. (background DR 30%, preproliferative DR 2.8% and proliferative DR 2.2%, respectively.) The prevalence of DR for previously and newly diagnosed diabetics were 45.2 and 28.3% (men 42.8 vs. 33.3% and women 47.5 vs. 24.8%), respectively. From multiple logistic regression analysis, duration of DM was the most important risk factor related to DR. Diabetic subjects treated with insulin had a higher risk of developing retinopathy than those treated with dietary control. The prevalence of nephropathy and neuropathy were 12.9 and 23.5%, respectively. For those patients with and those without nephropathy and neuropathy, the duration of DM, percentage of insulin treatment, percentage of hypertension, and fasting plasma glucose were significantly different. Diabetic duration, hypertension, insulin treatment and glycemic control consistently correlated with nephropathy and neuropathy. In conclusion, the prevalence of DM in Taiwan was between 4.9 and 9.2%, and the prevalence of IGT was 15.5%. The possible risk factors of newly diagnosed diabetes were age, family history of DM, BMI, SBP (hypertension), physical activity and triglyceride levels. Diabetes in Chinese subjects share many characteristics similar to other Asian populations. The burden imposed by the chronic complications of diabetes is massive. In Taiwan, the mortality rates from DM have increased greatly over the past 10 years. Reduction of the modificable risk factors such as BMI, hypertenion and dyslipidemia, and increase of physical activity and good glycemic control through public health efforts may help to reduce the risk of DM and its chronic complications.
Collapse
Affiliation(s)
- C Chang
- Department of Family Medicine, College of Medicine, National Cheng Kung University, Taipei, Taiwan, ROC
| | | | | | | | | | | | | | | |
Collapse
|
41
|
Kao PC, Wu TJ, Ho LL, Li XJ. Current trends and new approaches in the management of diabetes mellitus. Ann Clin Lab Sci 2000; 30:339-45. [PMID: 11045757] [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: 02/18/2023]
Abstract
Current trends in the management of type 2 diabetes mellitus, based on the 20-year United Kingdom Prospective Diabetic Study, include intensive treatment to control the blood glucose level and blood pressure in order to prevent or delay microvascular and cardiovascular complications. In the new millennium, type 2 diabetes will become epidemic in developing countries. If diabetes were to develop in 10% of the 1.2 billion population of China, the expense of intensive treatment would be immense. Laboratory tests are useful for detecting risk factors before the onset of the disease and convincing the general public to take preventive measures. Glucose tolerance testing is one of these tests. When glucose tolerance is impaired, 25% of beta-cell function is lost. Determining the plasma proinsulin level is another useful evaluation; impaired glucose tolerance accompanied by increased plasma proinsulin level is indicative of an enhanced risk that type 2 diabetes will develop within 5 years. Educating the public about eating a healthy diet and exercising may prevent the development of diabetes and thereby reduce the global prevalence of type 2 diabetes.
Collapse
Affiliation(s)
- P C Kao
- Department of Laboratory Medicine and Pathology, Mayo Clinic and Mayo Foundation, Rochester, Minnesota 55905, USA.
| | | | | | | |
Collapse
|
42
|
Athill CA, Wu TJ, Yashima M, Kim YH, Weiss JN, Huang HL, Karagueuzian HS, Chen PS. Influence of wavefront dynamics on transmembrane potential characteristics during atrial fibrillation. J Cardiovasc Electrophysiol 2000; 11:913-21. [PMID: 10969755 DOI: 10.1111/j.1540-8167.2000.tb00072.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
INTRODUCTION Although computerized mapping studies have demonstrated the presence of multiple wavelets during atrial fibrillation (AF) and that action potential amplitude and duration in AF vary significantly from beat to beat, no study has correlated the single cell action potential changes with the patterns of activation during AF. METHODS AND RESULTS We studied wavefront dynamics and single cell transmembrane potential (TMP) characteristics in 12 isolated perfused canine right atria. The endocardial surface was mapped using 477 bipolar electrodes while TMP was recorded with a standard glass microelectrode from an epicardial cell. AF was induced in the presence of acetylcholine. Successful simultaneous TMP recordings and activation maps were made during six episodes of AF and for a total of 141 activations. Large variations of TMP amplitude and duration were observed frequently; 34% of them have a low amplitude (<50% of the amplitude recorded during pacing). Low-amplitude potentials were recorded when the impaled cell was (1) in an area of random reentry (67%, n = 36); (2) within 3.2 mm of the core of organized functional reentry (22%, n = 12); (3) in the middle of two merging wavefronts (9%, n = 5); and (4) at the point of spontaneous wavebreak (2%, n = 1). CONCLUSION Large variations of TMP are observed frequently during in vitro AF. Low-amplitude TMPs are associated with specific patterns of AF activation wavefronts.
Collapse
Affiliation(s)
- C A Athill
- Department of Medicine, Cedars-Sinai Medical Center, Los Angeles, California 90048, USA
| | | | | | | | | | | | | | | |
Collapse
|
43
|
Cao JM, Fishbein MC, Han JB, Lai WW, Lai AC, Wu TJ, Czer L, Wolf PL, Denton TA, Shintaku IP, Chen PS, Chen LS. Relationship between regional cardiac hyperinnervation and ventricular arrhythmia. Circulation 2000; 101:1960-9. [PMID: 10779463 DOI: 10.1161/01.cir.101.16.1960] [Citation(s) in RCA: 325] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Sympathetic nerve activity is known to be important in ventricular arrhythmogenesis, but there is little information on the relation between the distribution of cardiac sympathetic nerves and the occurrence of spontaneous ventricular arrhythmias in humans. METHODS AND RESULTS We studied 53 native hearts of transplant recipients, 5 hearts obtained at autopsy of patients who died of noncardiac causes, and 7 ventricular tissues that had been surgically resected from the origin of ventricular tachycardia. The history was reviewed to determine the presence (group 1A) or absence (group 1B) of spontaneous ventricular arrhythmias. Immunocytochemical staining for S100 protein, neurofilament protein, tyrosine hydroxylase, and protein gene product 9.5 was performed to study the distribution and the density of sympathetic nerves. The average left ventricular ejection fraction was 0.22+/-0.07. A total of 30 patients had documented ventricular arrhythmias, including ventricular tachycardia and sudden cardiac death. A regional increase in sympathetic nerves was observed around the diseased myocardium and blood vessels in all 30 hearts. The density of nerve fibers as determined morphometrically was significantly higher in group 1A patients (total nerve number 19.6+/-11.2/mm(2), total nerve length 3.3+/-3.0 mm/mm(2)) than in group 1B patients (total nerve number 13.5+/-6.1/mm(2), total nerve length 2.0+/-1.1 mm/mm(2), P<0. 05 and P<0.01, respectively). CONCLUSIONS There is an association between a history of spontaneous ventricular arrhythmia and an increased density of sympathetic nerves in patients with severe heart failure. These findings suggest that abnormally increased postinjury sympathetic nerve density may be in part responsible for the occurrence of ventricular arrhythmia and sudden cardiac death in these patients.
Collapse
Affiliation(s)
- J M Cao
- Division of Cardiology, University of California Los Angeles School of Medicine, 90027, USA
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
44
|
Abstract
The glutamate analog N-methyl-D,L-aspartate (NMA) affects the regulation of GnRH and LH release in mammals. Several laboratories have reported a rapid and transient increase in GnRH mRNA levels of male rats after NMA injection. Studies employing the simultaneous measurements of nuclear GnRH primary transcript RNA, a reflection of gene transcription, and GnRH mRNA suggest that NMA's effect on GnRH gene expression in the rat is likely due to post-transcriptional regulation. Despite the increasingly widespread use of transgenic mice, surprisingly little is known about the regulation of GnRH gene expression in the mouse. In this study, we assessed in detail the effects of NMA on GnRH gene expression in adult male mice. In the first experiment, GnRH mRNA levels in mice killed 60-min post-NMA injection (20 mg/kg bw, ip; n=9/treatment group) were lower (P<0.05) when compared to controls (saline vehicle). In the second experiment, mice (n=7/treatment group) were administered NMA or saline vehicle and were killed at 15-, 60- and 120-min post-injection. Consistent with the first experiment, treatment with NMA resulted in a significant decrease (P<0.05) in cytoplasmic GnRH mRNA compared to control levels at 15- and 60-min but not 120-min. NMA treatment decreased the nuclear GnRH primary transcript RNA at 120-min but not at earlier time points. In summary, we have shown that regulation by NMA of GnRH gene expression in mice differs substantially from rats. This differential regulation of GnRH gene expression between rats and mice warrants further investigation.
Collapse
Affiliation(s)
- T J Wu
- Fishberg Research Center for Neurobiology, Mount Sinai School of Medicine, 1425 Madison Avenue, New York, NY, USA
| | | | | |
Collapse
|
45
|
Abstract
BACKGROUND Whether or not the muscle bundle within the ligament of Marshall (LOM) can serve as the origin of focal atrial fibrillation (AF) is unknown. METHODS AND RESULTS A total of 28 consecutive patients with paroxysmal AF underwent balloon-occlusion coronary sinus angiograms to identify the vein of Marshall (VOM). Attempts were then made to advance a 1.5-French electrophysiological catheter into the VOM via the coronary sinus orifice. In 17 of the 28 patients (10 of 17 were men aged 38+/-15 years), cannulation was successful. Double potentials were registered in 8 of these 17 patients. The first potential corresponded with local left atrial activation. The second potential was shorter and narrower than the first. The sequence of activation in the second potential in the VOM was proximal to distal. In 6 patients with direct VOM recordings, we documented that the origin of AF was in the muscle bundle within the LOM. Radiofrequency catheter ablation aimed at the insertion site of the VOM successfully terminated AF in 4 of these 6 patients. CONCLUSIONS (1) It is possible to cannulate and to record electrical potentials from the VOM. (2) The characteristics of the double potentials within the VOM suggest that the second potential is from the muscle bundle (Marshall bundle) within the LOM. (3) The Marshall bundle may be the origin of focal AF in some patients.
Collapse
Affiliation(s)
- C Hwang
- Utah Valley Regional Medical Center, Provo, Utah, USA
| | | | | | | | | |
Collapse
|
46
|
Abstract
Leptin, the ob gene product that can decrease caloric intake and increase energy expenditure, is functionally released by insulin from adipose tissue. Adenosine is thought to be an important regulator of the action of insulin in adipose tissue. The present study investigated the role of adenosine in the release of leptin by insulin in isolated rat white adipocytes. Release of leptin, measured by radioimmunoassay, from insulin-stimulated samples was seen after 30 min. Adenosine deaminase, at concentrations sufficient to metabolize endogenous adenosine, decreased insulin-stimulated leptin release. Also, the insulin-stimulated leptin release was completely blocked by the adenosine A1 receptor antagonist 8-cyclopentyl-1,3-dipropylxanthine (DPCPX). Mediation of endogenous adenosine in this action of insulin was further supported by the assay of adenosine released into the medium from adipocytes stimulated with insulin. In addition, activation of adenosine A1 receptors by N6-cyclopentyladenosine (CPA) induced an increase in leptin release in a concentration-dependent manner that could be blocked by antagonists, either DPCPX or 8-(p-sulfophenyl)theophylline (8-SPT). In the presence of U73312, a specific inhibitor of phospholipase C (PLC), CPA-stimulated leptin secretion from adipocytes was reduced in a concentration-dependent manner, but it was not affected by U73343, the negative control for U73312. Moreover, chelerythrine and GF 109203X diminished the CPA-stimulated leptin secretion at concentrations sufficient to inhibit protein kinase C (PKC). These results suggest that, in isolated white adipocytes, the released adenosine acts as a helper and/or a positive regulator for insulin in the release of leptin via an activation of adenosine A1 receptors that involves the PLC-PKC pathway.
Collapse
Affiliation(s)
- J T Cheng
- Department of Pharmacology, College of Medicine, National Cheng Kung University, Tainan City, Taiwan, Republic of China.
| | | | | | | | | | | | | |
Collapse
|
47
|
Abstract
Both electrophysiologic and anatomical substrates are important in the generation and maintenance of atrial fibrillation. This review discusses the nature of re-entrant wavefronts in atrial fibrillation and the importance of anatomical structures, such as the pectinate muscles, in the generation and maintenance of re-entry. The involvement of the pectinate muscle structure on intra-atrial re-entry may have significant implications for both ablation and pharmacologic management of patients with atrial fibrillation.
Collapse
Affiliation(s)
- P S Chen
- Cedars-Sinai Medical Center, Department of Medicine, University of California at Los Angeles School of Medicine, USA
| | | | | | | | | | | |
Collapse
|
48
|
Kim YH, Xie F, Yashima M, Wu TJ, Valderrábano M, Lee MH, Ohara T, Voroshilovsky O, Doshi RN, Fishbein MC, Qu Z, Garfinkel A, Weiss JN, Karagueuzian HS, Chen PS. Role of papillary muscle in the generation and maintenance of reentry during ventricular tachycardia and fibrillation in isolated swine right ventricle. Circulation 1999; 100:1450-9. [PMID: 10500048 DOI: 10.1161/01.cir.100.13.1450] [Citation(s) in RCA: 117] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND The role of papillary muscle (PM) in the generation and maintenance of reentry is unclear. METHODS AND RESULTS Computerized mapping (477 bipolar electrodes, 1.6-mm resolution) was performed in fibrillating right ventricles (RVs) of swine in vitro. During ventricular fibrillation (VF), reentrant wave fronts often transiently anchored to the PM. Tissue mass reduction was then performed in 10 RVs until VF converted to ventricular tachycardia (VT). In an additional 6 RVs, procainamide infusion converted VF to VT. Maps showed that 77% (34 of 44) of all VT episodes were associated with a single reentrant wave front anchored to the PM. Purkinje fiber potentials preceded the local myocardial activation, and these potentials were recorded mostly around the PM. When PM was trimmed to the level of endocardium (n = 4), sustained VT was no longer inducible. Transmembrane potential recordings (n = 5) at the PM revealed full action potential during pacing, without evidence of ischemia. Computer simulation studies confirmed the role of PM as a spiral wave anchoring site that stabilized wave conduction. CONCLUSIONS We conclude that PM is important in the generation and maintenance of reentry during VT and VF.
Collapse
Affiliation(s)
- Y H Kim
- Division of Cardiology, Department of Medicine, Cedars-Sinai Medical Center, UCLA School of Medicine, Los Angeles, Calif, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
49
|
Abstract
In an attempt to know the role of nitric oxide in the disease of insulin-dependent diabetic mellitus (IDDM), the present study examined the change of nitric oxide synthase (NOS) both the activity and gene expression in cerebrocortex of streptozotocin-induced diabetic rats (STZ-diabetic rats). The activity of NOS determined by conversion of [3H] L-arginine to [3H] L-citrulline was markedly decreased in STZ-diabetic rats. Northern blot showed that STZ-diabetic rats expressed a lower mRNA level of neuronal NOS (nNOS). Western blot showed a similar decrease of nNOS in STZ-diabetic rats. However, the NOS activity was increased in rats receiving repeated supply of glucose named glucose-challenged rats. Although the mRNA level of nNOS was not changed in the glucose-challenged rats, the immunoblot of nNOS was also decreased in glucose-challenged rats. These findings suggested that NOS was lowered in the brain of STZ-diabetic rats in a way unrelated to the increase of glucose.
Collapse
Affiliation(s)
- W J Yu
- Department of Pharmacology, College of Medicine, National Cheng Kung University, Tainan City, Taiwan
| | | | | | | | | | | |
Collapse
|
50
|
Doshi RN, Wu TJ, Yashima M, Kim YH, Ong JJ, Cao JM, Hwang C, Yashar P, Fishbein MC, Karagueuzian HS, Chen PS. Relation between ligament of Marshall and adrenergic atrial tachyarrhythmia. Circulation 1999; 100:876-83. [PMID: 10458726 DOI: 10.1161/01.cir.100.8.876] [Citation(s) in RCA: 102] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND The mechanism of the adrenergic atrial tachyarrhythmia is unclear. We hypothesize that the ligament of Marshall (LOM) is sensitive to adrenergic stimulation and may serve as a source of the adrenergic atrial tachyarrhythmia. METHODS AND RESULTS We performed computerized mapping studies in isolated-perfused canine left atrial tissues from normal dogs (n=9) and from dogs with chronic atrial fibrillation (AF) induced by 10 to 41 weeks of rapid pacing (n=3). Before isoproterenol, spontaneous activity occurred in only one normal tissue (cycle length, CL >1300 ms). During isoproterenol infusion, automatic rhythm was induced in both normal tissues (CL=578+/-172 ms) and AF tissues (CL=255+/-29 ms, P<0.05). The origin of spontaneous activity was mapped to the LOM. In the AF tissues, but not the normal tissues, we observed the transition from rapid automatic activity to multiple wavelet AF. Ablation of the LOM terminated the spontaneous activity and prevented AF. Immunocytochemical studies of the LOM revealed muscle tracts surrounded by tyrosine hydroxylase-positive (sympathetic) nerves. CONCLUSIONS We conclude that the LOM is richly innervated by sympathetic nerves and serves as a source of isoproterenol-sensitive focal automatic activity in normal canine atrium. The sensitivity to isoproterenol is upregulated after long-term rapid pacing and may contribute to the development of AF in this model.
Collapse
Affiliation(s)
- R N Doshi
- Division of Cardiology, Department of Medicine, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|