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Cai J, Li T, Lee HFV, Chang HC. Four-dimensional diffusion-weighted magnetic resonance imaging for stereotactic body radiation therapy in patients with abdominal cancer: abridged secondary publication. Hong Kong Med J 2023; 29 Suppl 7:18-23. [PMID: 38148651] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2023] Open
Affiliation(s)
- J Cai
- Department of Health Technology and Informatics, The Hong Kong Polytechnic University, Hong Kong SAR, China
| | - T Li
- Department of Health Technology and Informatics, The Hong Kong Polytechnic University, Hong Kong SAR, China
| | - H F V Lee
- Department of Clinical Oncology, The University of Hong Kong, Hong Kong SAR, China
| | - H C Chang
- Department of Biomedical Engineering, The Chinese University of Hong Kong, Hong Kong SAR, China
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Li ST, Chou YH, Huang HJ, Chang HC, Lee YC. Exploring the Benefits of 3D-Printed Bolus in Cone Beam CT for Modified Radical Mastectomy Breast Cancer. Int J Radiat Oncol Biol Phys 2023; 117:e685. [PMID: 37786014 DOI: 10.1016/j.ijrobp.2023.06.2152] [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] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) To improve the accuracy of superficial dose coverage for patients undergoing modified radical mastectomy (MRM), boluses are frequently applied to the skin surface of targeted region during radiotherapy. The irregular curvature of MRM breast cases results in discrepancies of dosimetry and poor contact. Additionally, the presence of an air gap causes unnecessary high-dose escalation and uncertainty in dose calculation, making the use of commercial flat bolus problematic. This study evaluated the effectiveness of 3D-printed bolus by comparing it to commercial bolus in setup variations and dosimetric compliance through daily cone-beam computed tomography (CBCT) scans. MATERIALS/METHODS Ten patients underwent MRM were divided into 2 groups. 5 patients treated with 0.5 cm commercial bolus as group A while the other 5 patients covered by 3D Bolus as group B. 3D bolus was made of polylactic acid filament (PLA) and contoured in advance with thickness of 0.5 cm on the surface of target. Positional errors were recorded through daily image guidance and compared with the images. Both groups had right-sided breast with neck lymph nodes involved and received 50 Gy in 25 fractions using 4 partial arcs of the volumetric modulated arc therapy (VMAT) technique. The CBCTs were recalculated through treatment planning system (TPS) to assess superficial dose coverage. A two-tailed student's t-test was applied. RESULTS Groups A and B pitch angles were -0.203 ± 0.837° and 0.334 ± 0.909° (p = 0.0003). Roll angle were 0.313 ± 0.728° and -0.633 ± 1.286° (p = 0.0000013). Yaw angle were -0.034 ± 0.872° and 0.018 ± 0.883° (p = 0.721). There was a trend of differences in the Z-axis and significant statistical differences in the pitch and roll angles due to aligning gel layers directly with group A's body surface, while 3D bolus rigidly adherence to group B's delineated curve. In the planned target volume (PTV), the CI and HI of group A were 0.9448±0.0208 and 1.2061±0.0448, respectively, while 0.9776±0.0144 and 1.1472±0.0206 (p<0.005) were for group B. As for the superficial region, which is defined from body surface to 0.5cm inside PTV, CI and HI of A were 0.8290±0.0599 and 1.4675±0.2434, while for B, they were 0.9753±0.0214 and 1.1330±0.0126, respectively (p<0.005). CONCLUSION The study analyzed the results through image comparison and investigated the CI and HI between two types of boluses. The 3D bolus reduces setup errors and improves dose coverage especially when superficial region is concerned. Better consistency of patient repositioning and dosimetry can be achieved and proved by daily assessment of CBCT scan. The customization of 3D bolus with integration of TPS and CT scans provides a solution to the inadequacies of commercial bolus. The results suggest that the use of 3D bolus is a promising development in radiation therapy for MRM breast cancer patients.
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Affiliation(s)
- S T Li
- Department of Radiation Oncology, Chung Shan Medical University Hospital, Taichung, Taiwan
| | - Y H Chou
- Department of Radiation Oncology, Chung Shan Medical University Hospital, Taichung, Taiwan
| | - H J Huang
- Department of Radiation Oncology, Chung Shan Medical University Hospital, Taichung, Taiwan
| | - H C Chang
- Department of Radiation Oncology, Chung Shan Medical University Hospital, Taichung, Taiwan
| | - Y C Lee
- Department of Radiation Oncology, Chung Shan Medical University Hospital, Taichung, Taiwan
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Ready DF, Chang HC. Interommatidial cells build a tensile collagen network during Drosophila retinal morphogenesis. Curr Biol 2023:S0960-9822(23)00549-3. [PMID: 37209679 DOI: 10.1016/j.cub.2023.04.066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Revised: 03/27/2023] [Accepted: 04/27/2023] [Indexed: 05/22/2023]
Abstract
Drosophila compound eye morphogenesis transforms a simple epithelium into an approximate hollow hemisphere comprised of ∼700 ommatidia, packed as tapering hexagonal prisms between a rigid external array of cuticular lenses and a parallel, rigid internal floor, the fenestrated membrane (FM). Critical to vision, photosensory rhabdomeres are sprung between these two surfaces, grading their length and shape accurately across the eye and aligning them to the optical axis. Using fluorescently tagged collagen and laminin, we show that that the FM assembles sequentially, emerging in the larval eye disc in the wake of the morphogenetic furrow as the original collagen-containing basement membrane (BM) separates from the epithelial floor and is replaced by a new, laminin-rich BM, which advances around axon bundles of newly differentiated photoreceptors as they exit the retina, forming fenestrae in this new, laminin-rich BM. In mid-pupal development, the interommatidial cells (IOCs) autonomously deposit collagen at fenestrae, forming rigid, tension-resisting grommets. In turn, stress fibers assemble in the IOC basal endfeet, where they contact grommets at anchorages mediated by integrin linked kinase (ILK). The hexagonal network of IOC endfeet tiling the retinal floor couples nearest-neighbor grommets into a supracellular tri-axial tension network. Late in pupal development, IOC stress fiber contraction folds pliable BM into a hexagonal grid of collagen-stiffened ridges, concomitantly decreasing the area of convex FM and applying essential morphogenetic longitudinal tension to rapidly growing rhabdomeres. Together, our results reveal an orderly program of sequential assembly and activation of a supramolecular tensile network that governs Drosophila retinal morphogenesis.
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Affiliation(s)
- Donald F Ready
- Department of Biological Sciences, Purdue University, 915 West State Street, West Lafayette, IN 47907-2054, USA
| | - Henry C Chang
- Department of Biological Sciences, Purdue University, 915 West State Street, West Lafayette, IN 47907-2054, USA.
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4
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Zhao H, Ren X, Kong R, Shi L, Li Z, Wang R, Ma R, Zhao H, Liu F, Chang HC, Chen CH, Li Z. Auxilin regulates intestinal stem cell proliferation through EGFR. Stem Cell Reports 2022; 17:1120-1137. [PMID: 35427486 PMCID: PMC9133653 DOI: 10.1016/j.stemcr.2022.03.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [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: 10/26/2020] [Revised: 03/14/2022] [Accepted: 03/15/2022] [Indexed: 12/11/2022] Open
Abstract
Adult tissue homeostasis is maintained by residential stem cells. The proliferation and differentiation of adult stem cells must be tightly balanced to avoid excessive proliferation or premature differentiation. However, how stem cell proliferation is properly controlled remains elusive. Here, we find that auxilin (Aux) restricts intestinal stem cell (ISC) proliferation mainly through EGFR signaling. aux depletion leads to excessive ISC proliferation and midgut homeostasis disruption, which is unlikely caused by defective Notch signaling. Aux is expressed in multiple types of intestinal cells. Interestingly, aux depletion causes a dramatic increase in EGFR signaling, with a strong accumulation of EGFR at the plasma membrane and an increased expression of EGFR ligands in response to tissue stress. Furthermore, Aux co-localizes and associates with EGFR. Finally, blocking EGFR signaling completely suppresses the defects caused by aux depletion. Together, these data demonstrate that Aux mainly safeguards EGFR activation to keep a proper ISC proliferation rate to maintain midgut homeostasis.
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Affiliation(s)
- Hang Zhao
- College of Life Sciences, Capital Normal University, Beijing 100048, China
| | - Xuejing Ren
- College of Life Sciences, Capital Normal University, Beijing 100048, China
| | - Ruiyan Kong
- College of Life Sciences, Capital Normal University, Beijing 100048, China
| | - Lin Shi
- College of Life Sciences, Capital Normal University, Beijing 100048, China
| | - Zhengran Li
- College of Life Sciences, Capital Normal University, Beijing 100048, China
| | - Runqi Wang
- College of Life Sciences, Capital Normal University, Beijing 100048, China
| | - Rui Ma
- Department of Neurology, Capital Medical University, Beijing 100053, China
| | - Huiqing Zhao
- College of Life Sciences, Capital Normal University, Beijing 100048, China
| | - Fuli Liu
- College of Life Sciences, Capital Normal University, Beijing 100048, China
| | - Henry C Chang
- Department of Biological Sciences, Purdue University, West Lafayette, IN 47907, USA
| | - Chun-Hong Chen
- Division of Molecular and Genomic Medicine, National Health Research Institute, 35, Keyan Road, Zhunan Town, Miaoli County 350, Taiwan
| | - Zhouhua Li
- College of Life Sciences, Capital Normal University, Beijing 100048, China.
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Chang HC, Kuo L, Niu DM, Yu WC. Left ventricular apical aneurysm in Fabry disease: implications for clinical significance and risk stratification. Eur Heart J Cardiovasc Imaging 2022. [DOI: 10.1093/ehjci/jeab289.435] [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
Funding Acknowledgements
Type of funding sources: None.
Background
More than 50% of patients with Fabry disease (FD) present with cardiac phenotype, and left ventricular hypertrophy (LVH) is the most frequent manifestation. Among FD patients with LVH, a rare and novel presentation of left ventricular apical aneurysm (LVAA) has been reported.
Purpose
This study aimed to investigate the clinical incidence of LVAA and its impacts on prognosis among FD patients.
Methods
We retrospectively analyzed 268 FD patients at a tertiary medical center between January 2003 to September 2020. Two patients with ischemic LVAA were excluded. LVH and LVAA were confirmed either by echocardiography (Figure 1A) or cardiovascular magnetic resonance imaging (Figure 1B). The primary endpoints were a composite of heart failure (HF) hospitalization, sustained ventricular tachycardia (VT), stroke, and death.
Results
Of 266 FD patients, there were 105 (39.5%) patients had LVH, and 11 (10.3%) of them had LVAAs (age 67.5 ± 9.5 years, 8 males [72.7%]). After a mean follow-up of 49.3 ± 34.8 months, 8 patients experienced primary endpoints, including 5 (45.5%) HF hospitalizations, 3 (27.3%) VT, 1 (9.1%) stroke, and 4 (36.4%) deaths. The risk for composite adverse events was significantly higher in patients with LVAA compared with those without (8 [72.7%] vs 17 [18.1%]), leading to significantly lower event-free survival in patients with LVAA (Log-Rank P < 0.001, Figure 2). The presence of LVAA was independently associated with an increased risk of composite adverse events (hazard ratio: 3.59; confidence interval: 1.30-9.91, P = 0.01) after adjusting for age, gender, advanced HF, renal function, dyslipidemia, atrial fibrillation, left ventricular ejection fraction of <40%, average E/e’, and LV mass index.
Conclusions
LVAA presents in around 10% of patients with Fabry cardiomyopathy and is strongly associated with an increased risk of adverse events. The identification of this phenotype would be useful to identify high-risk patients with Fabry cardiomyopathy, among whom more aggressive treatments may be considered. Abstract Figure. Apical aneurysm in Fabry cardiomyopathy Abstract Figure. KM curve of composite adverse events
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Affiliation(s)
- HC Chang
- Taipei Veterans General Hospital, Division of Cardiology, Department of Medicine, Taipei, Taiwan
| | - L Kuo
- Taipei Veterans General Hospital, Division of Cardiology, Department of Medicine, Taipei, Taiwan
| | - DM Niu
- Taipei Veterans General Hospital, Department of Pediatrics, Taipei, Taiwan
| | - WC Yu
- Taipei Veterans General Hospital, Division of Cardiology, Department of Medicine, Taipei, Taiwan
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Willy NM, Ferguson JP, Akatay A, Huber S, Djakbarova U, Silahli S, Cakez C, Hasan F, Chang HC, Travesset A, Li S, Zandi R, Li D, Betzig E, Cocucci E, Kural C. De novo endocytic clathrin coats develop curvature at early stages of their formation. Dev Cell 2021; 56:3146-3159.e5. [PMID: 34774130 DOI: 10.1016/j.devcel.2021.10.019] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 07/14/2021] [Accepted: 10/22/2021] [Indexed: 01/09/2023]
Abstract
Sculpting a flat patch of membrane into an endocytic vesicle requires curvature generation on the cell surface, which is the primary function of the endocytosis machinery. Using super-resolved live cell fluorescence imaging, we demonstrate that curvature generation by individual clathrin-coated pits can be detected in real time within cultured cells and tissues of developing organisms. Our analyses demonstrate that the footprint of clathrin coats increases monotonically during the formation of pits at different levels of plasma membrane tension. These findings are only compatible with models that predict curvature generation at the early stages of endocytic clathrin pit formation. We also found that CALM adaptors associated with clathrin plaques form clusters, whereas AP2 distribution is more homogenous. Considering the curvature sensing and driving roles of CALM, we propose that CALM clusters may increase the strain on clathrin lattices locally, eventually giving rise to rupture and subsequent pit completion at the edges of plaques.
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Affiliation(s)
- Nathan M Willy
- Department of Physics, The Ohio State University, Columbus, OH 43210, USA
| | - Joshua P Ferguson
- Department of Physics, The Ohio State University, Columbus, OH 43210, USA
| | - Ata Akatay
- Department of Physics, The Ohio State University, Columbus, OH 43210, USA
| | - Scott Huber
- Department of Physics, The Ohio State University, Columbus, OH 43210, USA
| | | | - Salih Silahli
- Department of Physics, The Ohio State University, Columbus, OH 43210, USA
| | - Cemal Cakez
- Department of Nuclear Engineering, University of New Mexico, Albuquerque, NM 87131, USA
| | - Farah Hasan
- Department of Physics, The Ohio State University, Columbus, OH 43210, USA
| | - Henry C Chang
- Department of Biological Sciences, Purdue University, West Lafayette, IN 47907, USA
| | - Alex Travesset
- Department of Physics and Astronomy, Iowa State University, Ames, IA 50011, USA; Ames Laboratory, Iowa State University, Ames, IA 50011, USA
| | - Siyu Li
- Department of Physics and Astronomy, University of California, Riverside, Riverside, CA 92521, USA
| | - Roya Zandi
- Department of Physics and Astronomy, University of California, Riverside, Riverside, CA 92521, USA
| | - Dong Li
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China; College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Eric Betzig
- Departments of Physics and Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA; Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA 20147, USA
| | - Emanuele Cocucci
- Division of Pharmaceutics and Pharmacology, College of Pharmacy and Comprehensive Cancer Center, The Ohio State University, Columbus, OH 43210, USA.
| | - Comert Kural
- Department of Physics, The Ohio State University, Columbus, OH 43210, USA; Interdisciplinary Biophysics Graduate Program, The Ohio State University, Columbus, OH 43210, USA.
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Ready DF, Chang HC. Calcium waves facilitate and coordinate the contraction of endfeet actin stress fibers in Drosophila interommatidial cells. Development 2021; 148:272616. [PMID: 34698814 DOI: 10.1242/dev.199700] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Accepted: 10/18/2021] [Indexed: 01/04/2023]
Abstract
Actomyosin contraction shapes the Drosophila eye's panoramic view. The convex curvature of the retinal epithelium, organized in ∼800 close-packed ommatidia, depends upon a fourfold condensation of the retinal floor mediated by contraction of actin stress fibers in the endfeet of interommatidial cells (IOCs). How these tensile forces are coordinated is not known. Here, we discover a novel phenomenon: Ca2+ waves regularly propagate across the IOC network in pupal and adult eyes. Genetic evidence demonstrates that IOC waves are independent of phototransduction, but require inositol 1,4,5-triphosphate receptor (IP3R), suggesting these waves are mediated by Ca2+ releases from ER stores. Removal of IP3R disrupts stress fibers in IOC endfeet and increases the basal retinal surface by ∼40%, linking IOC waves to facilitating stress fiber contraction and floor morphogenesis. Further, IP3R loss disrupts the organization of a collagen IV network underneath the IOC endfeet, implicating ECM and its interaction with stress fibers in eye morphogenesis. We propose that coordinated cytosolic Ca2+ increases in IOC waves promote stress fiber contractions, ensuring an organized application of the planar tensile forces that condense the retinal floor.
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Affiliation(s)
- Donald F Ready
- Department of Biological Sciences, Purdue University, 915 West State Street, West Lafayette, Indiana 47907-2054, USA
| | - Henry C Chang
- Department of Biological Sciences, Purdue University, 915 West State Street, West Lafayette, Indiana 47907-2054, USA
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Li A, Poon JWL, Ching S, Chan K, Chung TS, Yue CS, Ha SCN, Chang HC, Ng MY. Pulmonary pressure-to-longitudinal strain ratio by echocardiography: a rapid surrogate to magnetic resonance for right ventricular failure assessment. Eur Heart J Cardiovasc Imaging 2021. [DOI: 10.1093/ehjci/jeaa356.398] [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
Funding Acknowledgements
Type of funding sources: Public hospital(s). Main funding source(s): United Christian Hospital Ruttonjee and Tang Siu Kin Hospitals
Background
Better risk stratification in pulmonary hypertension (PH) by echocardiography (echo) to detect ventricular vascular uncoupling may act as gate-keeper for downstream management, such as MRI and expensive therapies. Studies showed modest correlation found between RV peak global longitudinal strain (RVGLS), which is afterload dependent, and right ventricular ejection fraction (RVEF)
Purpose
To test the accuracy and optimal cut-off of echo derived mean PA pressure-to-RVGLS ratio against MRI detected severe RV dysfunction (defined as RVEF< 35%), RV dilatation (defined as RVEDVi >87ml), and correlate native T1-values (nT1)
Method
Strain analyses by echo and volumetric assessment by 1.5 tesla MRI were performed in all patients. Contoured MRI short axis images provided RVEF. In a subgroup of pulmonary arterial hypertension (PAH), right heart catheterization and MRI non-contrast native T1 mapping were performed (Figure 1). Using previous study data, to identify a difference of 1.8 pressure-to-strain ratio between mild and severe PH with a variance of 2.2 , power of 80% and a significance level of 0.05, a total of 11 participants per group were needed
Result
Thirty-one PH patients (13 female, age 60 ± 14y, 13 had PAH) were recruited prospectively. Strong correlation was demonstrated between the mean PA pressure-to-RVGLS ratio to MRI derived RVEF (r = 0.80, p < 0.01), and to catheterization derived pulmonary vascular resistance and indexed cardiac output (r = -0.80, p= 0.001; r= -0.75, p = 0.003 respectively). The cut-off value of -2.5 had best accuracy in ROC analyses (Table 1)
In PAH patients, this ratio correlated with global nT1 at basal short-axis level (r= -0.91, p = 0.004), but not at the mid short-axis level. Their basal posterior interventricular insertion regions had significantly higher nT1 than those of age-matched normal controls at the same region on the same scanner (1256 ± 217 ms vs. 932 ± 25 ms, p = 0.04)
Conclusion
In terms of detection of severe right ventricular dysfunction by echocardiography, mean PA pressure-to-RVGLS ratio performed better than RVGLS alone, and a ratio cutoff of -2.5 predicts MRI determined ventricular vascular uncoupling in pulmonary hypertension
Table 1 Echo detect MRI AUC standard error 95% CI sens (%) spec (%) p Mean PA pressure -to-RVGLS ratio RVEF < 35% 0.86 0.073 0.71-1.00 72 83 0.007 RVEDVi > 87ml 0.81 0.081 0.65-0.97 83 70 0.004 RVGLS RVEF < 35% 0.76 0.100 0.57-0.96 60 83 0.048 RVEDVi > 87ml 0.73 0.090 0.55-0.91 67 70 0.032 PA pulmonary artery; RVGLS: RV global longitudinal strain; RVEDVi: indexed RV end-diastolic volume Abstract Figure 1
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Affiliation(s)
- A Li
- Chinese University of HK, Dept. of Medicine & Therapeutics., United Christian Hospital, Dept. of Med & Geri, ., Hong Kong
| | - J WL Poon
- Ruttonjee and Tang Shiu Kin Hospitals, Department of Medicine, Hong Kong, China
| | - S Ching
- United Christian Hospital, Dept. of Med & Geri, ,, Hong Kong
| | - K Chan
- Pro-care heart clinic, Hong Kong, Hong Kong
| | - TS Chung
- United Christian Hospital, Dept. of Med & Geri, ,, Hong Kong
| | - CS Yue
- United Christian Hospital, Dept. of Med & Geri, ,, Hong Kong
| | - S CN Ha
- United Christian Hospital, ,, Hong Kong
| | - HC Chang
- The University of Hong Kong, Department of Diagnostic Radiology, Hong Kong, China
| | - MY Ng
- The University of Hong Kong, Department of Diagnostic Radiology, Hong Kong, China
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Huang WM, Lee CW, Sung SH, Chang HC. P923Feasibility of the transcatheter mitral valve repair as the rescue therapy for patients with severe mitral regurgitation and endangered heart failure. Eur Heart J 2019. [DOI: 10.1093/eurheartj/ehz747.0518] [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: 11/12/2022] Open
Abstract
Abstract
Background
For those who carry high or prohibitive surgical risk, the transcatheter edge-to edge mitral valve repair using MitraClip has been a safe and effective treatment for severe mitral regurgitation (MR). In patients with severe MR and cardiogenic shock under hemodynamic supporting devices, emergent surgical mitral valve interventions carry extremely high risk for peri-operative morbidities and mortalities. The feasibility and efficacy of emergent MitraClip to rescue patients in critical conditions remains elucidate.
Methods
Patients with severe MR were evaluated by the heart team and those with high or prohibitive surgical risks were referred to receive MitraClip procedures. Emergent MitraClip were conducted in patients with unstable hemodynamics and under mechanical or inotropic support. The hemodynamic measures, transthoracic echocardiography, transesophageal echocardiography, and blood tests were performed before MitraClip procedures. Procedural success was defined as having mild mitral regurgitation immediately after MitraClip, and patients were free from in-hospital mortality. Clinical and echocardiographic outcomes were followed by telephones and clinics.
Results
Among 50 consecutive patients (74.7±11.2 years, 74% male), 8 emergent MitraClip procedures were conducted to rescue patients with cardiogenic shock. Extracorporeal membrane oxygenation were used in 2 patients and intra-aortic balloon pump were applied in 4 patients (50%). The rest of 4 patients received continuous inotropic agent administration. Compare to those who underwent elective procedures, patients underwent emergent MitraClip had higher surgical risk profile (Euroscore II 34.8% vs 5.1% and STS score 19.7% vs 5.1%), poorer renal function and higher right atrial pressure. There was no peri-procedural death, myocardial infarction, stroke or any adverse events requiring emergent cardiac surgery in both groups. Mild mitral regurgitation was achieved in 87.5% patients from the emergent group and 95.2% patients in the elective group (P=0.514). In follow up, there were 5 deaths (three in the emergent group), including 2 non-cardiovascular deaths. The Kaplan-Meier analysis showed patients who underwent emergent procedures have poorer long-term survival rate as compare to those who received elective procedures. (P value = 0.008).
Conclusions
When open-heart surgery is not feasible and deferred due to excessive risk, trans-catheter mitral valve repair is an alternative way to rescue patients in cardiogenic shock status. The emergent MitraClip procedure may provide comparable safety and efficacy in treating patients with severe MR and unstable hemodynamics.
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Affiliation(s)
- W M Huang
- Taipei Veterans General Hospital, Cardiology, Taipei, Taiwan
| | - C W Lee
- Taipei Veterans General Hospital, Cardiology, Taipei, Taiwan
| | - S H Sung
- Taipei Veterans General Hospital, Cardiology, Taipei, Taiwan
| | - H C Chang
- Taipei Veterans General Hospital, Cardiology, Taipei, Taiwan
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Stegeman R, Hall H, Escobedo SE, Chang HC, Weake VM. Proper splicing contributes to visual function in the aging Drosophila eye. Aging Cell 2018; 17:e12817. [PMID: 30003673 PMCID: PMC6156539 DOI: 10.1111/acel.12817] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Revised: 06/06/2018] [Accepted: 06/18/2018] [Indexed: 12/19/2022] Open
Abstract
Changes in splicing patterns are a characteristic of the aging transcriptome; however, it is unclear whether these age-related changes in splicing facilitate the progressive functional decline that defines aging. In Drosophila, visual behavior declines with age and correlates with altered gene expression in photoreceptors, including downregulation of genes encoding splicing factors. Here, we characterized the significance of these age-regulated splicing-associated genes in both splicing and visual function. To do this, we identified differential splicing events in either the entire eye or photoreceptors of young and old flies. Intriguingly, aging photoreceptors show differential splicing of a large number of visual function genes. In addition, as shown previously for aging photoreceptors, aging eyes showed increased accumulation of circular RNAs, which result from noncanonical splicing events. To test whether proper splicing was necessary for visual behavior, we knocked down age-regulated splicing factors in photoreceptors in young flies and examined phototaxis. Notably, many of the age-regulated splicing factors tested were necessary for proper visual behavior. In addition, knockdown of individual splicing factors resulted in changes in both alternative splicing at age-spliced genes and increased accumulation of circular RNAs. Together, these data suggest that cumulative decreases in splicing factor expression could contribute to the differential splicing, circular RNA accumulation, and defective visual behavior observed in aging photoreceptors.
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Affiliation(s)
- Rachel Stegeman
- Department of BiochemistryPurdue UniversityWest LafayetteIndiana
- Present address:
University of Minnesota Medical SchoolMinneapolisMinnesota
| | - Hana Hall
- Department of BiochemistryPurdue UniversityWest LafayetteIndiana
| | | | - Henry C. Chang
- Department of Biological SciencesPurdue UniversityWest LafayetteIndiana
| | - Vikki M. Weake
- Department of BiochemistryPurdue UniversityWest LafayetteIndiana
- Purdue University Center for Cancer ResearchPurdue UniversityWest LafayetteIndiana
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Tang YW, Chen IC, Yen JH, Lu CT, Lai CS, Liu HJ, Chang HC, Chen YW. Fluid Restriction for Treatment of “Fluid Creep” after Acute Burn Resuscitation. HONG KONG J EMERG ME 2017. [DOI: 10.1177/102490791402100404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Objective Fluid creep in patients recovering from acute burns still exists, despite the use of a more treatment conservative approach. Most of our severe burn patients develop fluid overload and body weight increase after acute fluid resuscitation. How to quickly return patients to their pre-injury body weight is an important issue. Methods Right after acute fluid resuscitation, we applied a “total fluid requirement” volume (usually 1/2 to 2/3 of initial 24 hour volume) and strictly monitored patients' hourly urine (between 0.5-1 ml/kg/hr). Patients' responses (body weight, enteric feeding amount, pulmonary condition, etc.) were also closely monitored and frequent adjustments of fluid volume administration were performed simultaneously. Results Most patients regained their pre-injury body weight within 2-3 weeks. Enteric feeding also improved markedly. No patients had severe oedema-related complications. Conclusions Stricter fluid administration after acute burn fluid resuscitation is advised for allowing patients to reduce body weight to their pre-injury weight or at least close to it. We use pre-injury body weight, enteric feeding and urine output as our guides. (Hong Kong j.emerg.med. 2014;21:222-229)
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Chang HC, Lin JF, Yeh KH. Paddle Position and Contact Force: An Important Step to Check When Troubleshooting for Refractory Ventricular Fibrillation. HONG KONG J EMERG ME 2017. [DOI: 10.1177/102490791602300506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Ventricular fibrillation (VF) is a lethal medical emergency that requires immediate defibrillation. VF is resistant when it persists after three or more defibrillator shocks. Successful defibrillation requires depolarisation of a critical mass of myocardium. Several variables, such as the length of time in VF, body type, total energy used, and energy waveform have been reported to be associated with the success rate of defibrillation. Correct paddle position and good contact force to create an adequate current flow through the heart is essential for defibrillation. We report a patient who developed VF because of acute myocardial infarction that was resistant to a total of 13 shocks. The cause of shock-resistant VF was diagnosed by noticing the skin marks caused by the defibrillator paddle that indicated incorrect paddle position and inadequate paddle force. By checking the skin marks, an emergency physician could make a correct diagnosis within a few seconds and save a patient.
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13
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Lim S, Sato T, Marino F, Stillitano F, Pioner JM, Haase T, Pianezzi E, Sivakumaran P, Hernandez D, Wong RCB, Taylor C, Dusting G, Pebay A, Bayeva M, Chang HC, Shapiro JS, Yar S, Ardehali H, Camporeale A, Avalle L, Heymans S, Roman B, Kotelianski V, Poli V, Karakikes I, Nonnenmacher M, Ceholski D, Zhang L, Hulot JS, Cai CL, Kranias EG, Hajjar RJ, Racca AW, Klaiman JM, Guan X, Pabon L, Muskheli V, Macadangdang J, Kim DH, Mack DL, Childers MK, Tesi C, Poggesi C, Murry CE, Regnier M, Krause J, Mueller C, Stenzig J, Roethemeier C, Wild PS, Blankenberg S, Zeller T, Altomare C, Cervio E, Bolis S, Moccetti T, Camici GG, Barile L, Vassalli GG. Moderated Poster session - Genetic, Epigenetic & Integrative480Inhibiting mitochondrial fission with Mdivi-1 directs cardiac differentiation of human induced pluripotent stem cells via protein kinase CK2481A novel role of tristetraprolin in preventing mitochondrial dysfunction in the heart against iron deficiency by optimizing expression of Rieske iron-sulfur protein482Different therapeutic approaches to downregulate the activation of the hepatic interleukin-6/stat3/complement pathway in two models of autoimmune myocarditis483In vitro and in vivo genome engineering of Dilated Cardiomyopathy caused by phospholamban R14 deletion.484Contractile dysfunction of induced pluripotent stem cell-derived cardiomyocytes from a duchenne muscular dystrophy patient485Cigarette smoking increases expression of the G protein-coupled receptor 15 mRNA by change in CpG methylation486Cardiogenic potential of iPSC from cardiac progenitor cells. Cardiovasc Res 2016. [DOI: 10.1093/cvr/cvw146] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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14
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Meuret S, Tizei LHG, Cazimajou T, Bourrellier R, Chang HC, Treussart F, Kociak M. Photon bunching in cathodoluminescence. Phys Rev Lett 2015; 114:197401. [PMID: 26024196 DOI: 10.1103/physrevlett.114.197401] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Indexed: 05/22/2023]
Abstract
We have measured the second order correlation function [g^{(2)}(τ)] of the cathodoluminescence intensity resulting from the excitation by fast electrons of defect centers in wide band-gap semiconductor nanocrystals of diamond and hexagonal boron nitride. We show that the cathodoluminescence second order correlation function g^{(2)}(τ) of multiple defect centers is dominated by a large, nanosecond zero-delay bunching (g^{(2)}(0)>30), in stark contrast to their flat photoluminescence g^{(2)}(τ) function. We have developed a model showing that this bunching can be attributed to the synchronized emission from several defect centers excited by the same electron through the deexcitation of a bulk plasmon into few electron-hole pairs.
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Affiliation(s)
- S Meuret
- Laboratoire de Physique des Solides, UMR 8502 CNRS and Université Paris-Sud, Orsay 91405, France
| | - L H G Tizei
- Laboratoire de Physique des Solides, UMR 8502 CNRS and Université Paris-Sud, Orsay 91405, France
| | - T Cazimajou
- Laboratoire de Physique des Solides, UMR 8502 CNRS and Université Paris-Sud, Orsay 91405, France
| | - R Bourrellier
- Laboratoire de Physique des Solides, UMR 8502 CNRS and Université Paris-Sud, Orsay 91405, France
| | - H C Chang
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 106, Taiwan
| | - F Treussart
- Laboratoire Aimé Cotton, UMR 9188 CNRS, Université Paris Sud and ENS Cachan, Orsay 91405, France
| | - M Kociak
- Laboratoire de Physique des Solides, UMR 8502 CNRS and Université Paris-Sud, Orsay 91405, France
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15
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Goh SK, Tompsett DA, Saines PJ, Chang HC, Matsumoto T, Imai M, Yoshimura K, Grosche FM. Ambient pressure structural quantum critical point in the phase diagram of (Ca(x)Sr(1-x))(3)Rh(4)Sn(13). Phys Rev Lett 2015; 114:097002. [PMID: 25793843 DOI: 10.1103/physrevlett.114.097002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Indexed: 06/04/2023]
Abstract
The quasiskutterudite superconductor Sr_{3}Rh_{4}Sn_{13} features a pronounced anomaly in electrical resistivity at T^{*}∼138 K. We show that the anomaly is caused by a second-order structural transition, which can be tuned to 0 K by applying physical pressure and chemical pressure via the substitution of Ca for Sr. A broad superconducting dome is centered around the structural quantum critical point. Detailed analysis of the tuning parameter dependence of T^{*} as well as insights from lattice dynamics calculations strongly support the existence of a structural quantum critical point at ambient pressure when the fraction of Ca is 0.9 (i.e., x_{c}=0.9). This establishes the (Ca_{x}Sr_{1-x})_{3}Rh_{4}Sn_{13} series as an important system for exploring the physics of structural quantum criticality without the need of applying high pressures.
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Affiliation(s)
- S K Goh
- Department of Physics, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
- Cavendish Laboratory, University of Cambridge, J. J. Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - D A Tompsett
- Department of Chemistry, Imperial College London, South Kensington SW7 2AZ, United Kingdom
| | - P J Saines
- Department of Chemistry, University of Oxford, Inorganic Chemistry Laboratory, South Parks Road, Oxford OX1 3QR, United Kingdom
| | - H C Chang
- Cavendish Laboratory, University of Cambridge, J. J. Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - T Matsumoto
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - M Imai
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - K Yoshimura
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
| | - F M Grosche
- Cavendish Laboratory, University of Cambridge, J. J. Thomson Avenue, Cambridge CB3 0HE, United Kingdom
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16
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Chen JF, Yang KH, Zhang ZL, Chang HC, Chen Y, Sowa H, Gürbüz S. A systematic review on the use of daily subcutaneous administration of teriparatide for treatment of patients with osteoporosis at high risk for fracture in Asia. Osteoporos Int 2015; 26:11-28. [PMID: 25138261 DOI: 10.1007/s00198-014-2838-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Accepted: 07/31/2014] [Indexed: 12/15/2022]
Abstract
This systematic review aimed to examine the evidence for teriparatide in Asia for osteoporosis with a high fracture risk and for exploratory (unapproved) bone-related indications. MEDLINE (1946+), EMBASE (1966+), and ClinicalTrials.gov (2008+) were searched (16 August 2013); all studies of daily subcutaneous teriparatide 20 μg for bone-related conditions from China, Hong Kong, Japan, Republic of Korea, Philippines, Singapore, and Taiwan were included. Evidence on efficacy/safety was retrieved primarily from randomized controlled trials (10 publications) of postmenopausal women from Japan and China. In these studies, teriparatide was well tolerated; subjects had significantly greater increases in lumbar spine bone mineral density (BMD) from baseline compared with placebo, antiresorptive agents, or elcatonin/calcitonin; bone turnover markers increased from baseline and were sustained at elevated levels during teriparatide treatment. Few studies reported fracture risk, pain, or quality of life; one study showed a lower incidence of new-onset vertebral fracture with teriparatide versus antiresorptive agents. Nonrandomized studies (nine publications, one unpublished trial) conducted mainly in Taiwan, Japan, and the Republic of Korea provided supporting data for efficacy. The exploratory (unapproved) use of teriparatide (17 publications) for fracture healing and osteonecrosis of the jaw was described primarily in case reports. The clinical effectiveness of teriparatide for treatment of postmenopausal women with osteoporosis who are at high risk of fracture in Asia is focused primarily on improvements in BMD and tolerability. Recommended additional studies may include assessment of fracture risk and the effect of teriparatide on pain, quality of life, and mortality in Asia.
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Affiliation(s)
- J F Chen
- Department of Endocrinology and Metabolism, Chang Gung Memorial Hospital, No. 123, Dapi Rd, Niaosong District, Kaohsiung City, 83301, Taiwan
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17
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Liang CJ, Chang YC, Chang HC, Wang CK, Hung YC, Lin YE, Chan CC, Chen CH, Chang HY, Sang TK. Derlin-1 regulates mutant VCP-linked pathogenesis and endoplasmic reticulum stress-induced apoptosis. PLoS Genet 2014; 10:e1004675. [PMID: 25255315 PMCID: PMC4177747 DOI: 10.1371/journal.pgen.1004675] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2014] [Accepted: 08/14/2014] [Indexed: 12/13/2022] Open
Abstract
Mutations in VCP (Valosin-containing protein), an AAA ATPase critical for ER-associated degradation, are linked to IBMPFD (Inclusion body myopathy with Paget disease and frontotemporal dementia). Using a Drosophila IBMPFD model, we have identified the ER protein Derlin-1 as a modifier of pathogenic TER94 (the fly VCP homolog) mutants. Derlin-1 binds to TER94 directly, and this interaction is essential for Derlin-1 overexpression to suppress the pathogenic TER94-induced neurodegeneration. Derlin-1 overexpression reduces the elevated ATPase activity of pathogenic TER94, implying that IBMPFD is caused by ATPase hyper-activation. Under physiological condition, Derlin-1 expression is increased upon ER stress to recruit TER94 to the ER. However, in response to severe ER stress, Derlin-1 is required for activating apoptosis to eliminate damaged cells. This pro-apoptotic response is mimicked by Derlin-1 overexpression, which elicits acute ER stress and triggers apoptosis via a novel C-terminal motif (α). As this Derlin-1-dependent cell death is negated by TER94 overexpression, we propose that while Derlin-1 and VCP work cooperatively in ER stress response, their imbalance has a role in removing cells suffering prolonged ER stress. We have previously developed a fly model for IBMPFD (inclusion body myopathy with Paget disease and frontotemporal dementia) and demonstrated that specific mutations in VCP gene, a highly conserved ATPase, cause muscle and neuron degeneration by depleting cellular ATP level. Using this model, we show that expression of Derlin-1, an ER membrane protein capable of directly interacting with VCP, restores the normal cellular ATP level and suppresses IBMPFD-like neurodegeneration. As Derlin-1 expression can be induced by tunicamycin (an antibiotic) in experimental systems, our findings may yield new therapeutic strategies for VCP-linked diseases. In addition, we have obtained important insights regarding Derlin-1 function under physiological conditions. ER stress, caused by accumulation of improperly folded proteins, results in increased Derlin-1 expression, which is important for ER stress-induced cell death. We propose that Derlin-1 promotes ER homeostasis through multiple mechanisms. In addition to cooperating with VCP to extract improperly folded proteins from the ER, elevated Derlin-1 expression removes cells suffering from irreparable ER stress, thus preventing these damaged cells from further harming the organisms.
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Affiliation(s)
- Cyong-Jhih Liang
- Institute of Biotechnology, Department of Life Science, National Tsing Hua University, Hsinchu, Taiwan
| | - Ya-Chu Chang
- Institute of Biotechnology, Department of Life Science, National Tsing Hua University, Hsinchu, Taiwan
| | - Henry C. Chang
- Department of Biological Sciences, Purdue University, West Lafayette, Indiana, United States of America
| | - Chung-Kang Wang
- Institute of Biotechnology, Department of Life Science, National Tsing Hua University, Hsinchu, Taiwan
| | - Yu-Chien Hung
- Institute of Biotechnology, Department of Life Science, National Tsing Hua University, Hsinchu, Taiwan
| | - Ying-Er Lin
- Institute of Biotechnology, Department of Life Science, National Tsing Hua University, Hsinchu, Taiwan
| | - Chia-Ching Chan
- Institute of Biotechnology, Department of Life Science, National Tsing Hua University, Hsinchu, Taiwan
| | - Chun-Hong Chen
- Institute of Molecular and Genomic Medicine, National Health Research Institutes, Zhunan, Miaoli County, Taiwan
| | - Hui-Yun Chang
- Brain Research Center, National Tsing Hua University, Hsinchu, Taiwan
- Institute of Systems Neuroscience, National Tsing Hua University, Hsinchu, Taiwan
| | - Tzu-Kang Sang
- Institute of Biotechnology, Department of Life Science, National Tsing Hua University, Hsinchu, Taiwan
- Brain Research Center, National Tsing Hua University, Hsinchu, Taiwan
- * E-mail:
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18
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O'Neill PF, Ben Azouz A, Vázquez M, Liu J, Marczak S, Slouka Z, Chang HC, Diamond D, Brabazon D. Advances in three-dimensional rapid prototyping of microfluidic devices for biological applications. Biomicrofluidics 2014; 8:052112. [PMID: 25538804 PMCID: PMC4241764 DOI: 10.1063/1.4898632] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Accepted: 10/06/2014] [Indexed: 05/02/2023]
Abstract
The capability of 3D printing technologies for direct production of complex 3D structures in a single step has recently attracted an ever increasing interest within the field of microfluidics. Recently, ultrafast lasers have also allowed developing new methods for production of internal microfluidic channels within the bulk of glass and polymer materials by direct internal 3D laser writing. This review critically summarizes the latest advances in the production of microfluidic 3D structures by using 3D printing technologies and direct internal 3D laser writing fabrication methods. Current applications of these rapid prototyped microfluidic platforms in biology will be also discussed. These include imaging of cells and living organisms, electrochemical detection of viruses and neurotransmitters, and studies in drug transport and induced-release of adenosine triphosphate from erythrocytes.
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Affiliation(s)
| | | | | | - J Liu
- Advanced Processing Technology Research Centre, School of Mechanical and Manufacturing Engineering, Dublin City University , Dublin, Ireland
| | - S Marczak
- Centre for Microfluidics and Medical Diagnostics, University of Notre Dame , Notre Dame, Indiana 46556, USA
| | - Z Slouka
- Centre for Microfluidics and Medical Diagnostics, University of Notre Dame , Notre Dame, Indiana 46556, USA
| | - H C Chang
- Centre for Microfluidics and Medical Diagnostics, University of Notre Dame , Notre Dame, Indiana 46556, USA
| | - D Diamond
- Insight Centre for Data Analytics, National Centre for Sensor Research, Dublin City University , Dublin, Ireland
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19
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Stoller ML, Chang HC, Fekete DM. Bicistronic gene transfer tools for delivery of miRNAs and protein coding sequences. Int J Mol Sci 2013; 14:18239-55. [PMID: 24013374 PMCID: PMC3794778 DOI: 10.3390/ijms140918239] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2013] [Revised: 08/08/2013] [Accepted: 08/13/2013] [Indexed: 01/07/2023] Open
Abstract
MicroRNAs (miRNAs) are a category of small RNAs that modulate levels of proteins via post-transcriptional inhibition. Currently, a standard strategy to overexpress miRNAs is as mature miRNA duplexes, although this method is cumbersome if multiple miRNAs need to be delivered. Many of these miRNAs are found within introns and processed through the RNA polymerase II pathway. We have designed a vector to exploit this naturally-occurring intronic pathway to deliver the three members of the sensory-specific miR-183 family from an artificial intron. In one version of the vector, the downstream exon encodes the reporter (GFP) while another version encodes a fusion protein created between the transcription factor Atoh1 and the hemaglutinin epitope, to distinguish it from endogenous Atoh1. In vitro analysis shows that the miRNAs contained within the artificial intron are processed and bind to their targets with specificity. The genes downstream are successfully translated into protein and identifiable through immunofluorescence. More importantly, Atoh1 is proven functional through in vitro assays. These results suggest that this cassette allows expression of miRNAs and proteins simultaneously, which provides the opportunity for joint delivery of specific translational repressors (miRNA) and possibly transcriptional activators (transcription factors). This ability is attractive for future gene therapy use.
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Affiliation(s)
- Michelle L. Stoller
- Department of Biological Sciences, Purdue University, 915 W State St, West Lafayette, IN 47907-1392, USA; E-Mails: (M.L.S.); (H.C.C.)
- Purdue University Center for Cancer Research, Purdue University, 201 S University Dr, West Lafayette, IN 47907-2064, USA
| | - Henry C. Chang
- Department of Biological Sciences, Purdue University, 915 W State St, West Lafayette, IN 47907-1392, USA; E-Mails: (M.L.S.); (H.C.C.)
- Purdue University Center for Cancer Research, Purdue University, 201 S University Dr, West Lafayette, IN 47907-2064, USA
| | - Donna M. Fekete
- Department of Biological Sciences, Purdue University, 915 W State St, West Lafayette, IN 47907-1392, USA; E-Mails: (M.L.S.); (H.C.C.)
- Purdue University Center for Cancer Research, Purdue University, 201 S University Dr, West Lafayette, IN 47907-2064, USA
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +1-765-496-3058; Fax: +1-765-494-0876
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20
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Ermakova A, Pramanik G, Cai JM, Algara-Siller G, Kaiser U, Weil T, Tzeng YK, Chang HC, McGuinness LP, Plenio MB, Naydenov B, Jelezko F. Detection of a few metallo-protein molecules using color centers in nanodiamonds. Nano Lett 2013; 13:3305-9. [PMID: 23738579 DOI: 10.1021/nl4015233] [Citation(s) in RCA: 106] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Nanometer-sized diamonds containing nitrogen-vacancy defect centers (NV) are promising nanosensors in biological environments due to their biocompatibility, bright fluorescence, and high magnetic sensitivity at ambient conditions. Here we report on the detection of ferritin molecules using magnetic noise induced by the inner paramagnetic iron as a contrast mechanism. We observe a significant reduction of both coherence and relaxation time due to the presence of ferritin on the surface of nanodiamonds. Our theoretical model is in excellent agreement with the experimental data and establishes this method as a novel sensing technology for proteins.
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Affiliation(s)
- A Ermakova
- Institut für Quantenoptik and IQST, ‡Institut für Organische Chemie III and IQST, §Institut für Theoretische Physik and IQST, and ∥Materialwissenschaftliche Elektronenmikroskopie and IQST, Albert-Einstein Allee 11, Universität Ulm , 89069 Ulm, Germany
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21
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Yu X, Li X, Jiang G, Wang X, Chang HC, Hsu WH, Li Q. Isradipine prevents rotenone-induced intracellular calcium rise that accelerates senescence in human neuroblastoma SH-SY5Y cells. Neuroscience 2013; 246:243-53. [PMID: 23664925 DOI: 10.1016/j.neuroscience.2013.04.062] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2013] [Revised: 04/16/2013] [Accepted: 04/30/2013] [Indexed: 01/11/2023]
Abstract
Previous research demonstrated that rotenone (RT) induces neuronal injury partially by increasing intracellular Ca(2+) concentrations ([Ca(2+)]i), and inducing oxidative stress, leading to a neurodegenerative disorder. However, the mechanism of RT-induced injury remains elusive. Recent work revealed that Ca(2+) signaling is important for RT-induced senescence in human neuroblastoma SH-SY5Y cells. In the present study, we found that in SH-SY5Y cells, RT increased [Ca(2+)]i, senescence associated β-galactosidase activity, aggregation of lipofuscin, production of reactive oxygen species, G1/G0 cell cycle arrest, and activation of p53/p21 signaling proteins. In addition, RT decreased the expression of the signaling proteins for cell proliferation and survival, Cyclin-dependent kinase 2 (CDK2), cyclin D1, and Akt. Pretreatment of SH-SY5Y cells with isradipine, an L-type Ca(2+) channel blocker, or EGTA antagonized these effects of RT. These results suggested that application of isradipine might be a novel approach to prevent RT-induced neurodegenerative disorder such as Parkinson's disease.
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Affiliation(s)
- X Yu
- Key Laboratory of Xin'an Medicine, Ministry of Education, Anhui Province Key Laboratory of R&D of Chinese Medicine, Anhui University of Traditional Chinese Medicine, Hefei 230038, China
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Abdallah AM, Zhou X, Kim C, Shah KK, Hogden C, Schoenherr JA, Clemens JC, Chang HC. Activated Cdc42 kinase regulates Dock localization in male germ cells during Drosophila spermatogenesis. Dev Biol 2013; 378:141-53. [PMID: 23562806 DOI: 10.1016/j.ydbio.2013.02.025] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2012] [Revised: 02/15/2013] [Accepted: 02/16/2013] [Indexed: 11/25/2022]
Abstract
Deregulation of the non-receptor tyrosine kinase ACK1 (Activated Cdc42-associated kinase) correlates with poor prognosis in cancers and has been implicated in promoting metastasis. To further understand its in vivo function, we have characterized the developmental defects of a null mutation in Drosophila Ack, which bears a high degree of sequence similarity to mammalian ACK1 but lacks a CRIB domain. We show that Ack, while not essential for viability, is critical for sperm formation. This function depends on Ack tyrosine kinase activity and is required cell autonomously in differentiating male germ cells at or after the spermatocyte stage. Ack associates predominantly with endocytic clathrin sites in spermatocytes, but disruption of Ack function has no apparent effect on clathrin localization and receptor-mediated internalization of Boss (Bride of sevenless) protein in eye discs. Instead, Ack is required for the subcellular distribution of Dock (dreadlocks), the Drosophila homolog of the SH2- and SH3-containing adaptor protein Nck. Moreover, Dock forms a complex with Ack, and the localization of Dock in male germ cells depends on its SH2 domain. Together, our results suggest that Ack-dependent tyrosine phosphorylation recruits Dock to promote sperm differentiation.
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Affiliation(s)
- Abbas M Abdallah
- Department of Biological Sciences, Purdue University, 915 West State Street, West Lafayette, IN 47907-2054, USA
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Chang CC, Chang HC, Wu CH, Chang CY, Liao CC, Chen TL. Adverse postoperative outcomes in surgical patients with immune thrombocytopenia. Br J Surg 2013; 100:684-92; discussion 693. [DOI: 10.1002/bjs.9065] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/10/2012] [Indexed: 01/09/2023]
Abstract
Abstract
Background
Patients with immune thrombocytopenia (ITP) are likely to have various medical co-morbidities, yet their global features regarding adverse postoperative outcomes and use of medical resources when undergoing major surgery are unknown. The objective of this study was to validate whether ITP is an independent risk factor for adverse postoperative outcomes, and to explore the potential clinical predictors of outcomes after major surgery among patients with ITP.
Methods
A retrospective population-based cohort study was conducted using Taiwan's National Health Insurance Research Database, controlling for preoperative co-morbidities by means of multiple logistic regression. Major postoperative complication and mortality rates, and in-hospital medical costs were analysed.
Results
The study included 11 085 surgical patients with ITP and 44 340 controls without ITP matched for sex, age, and type of surgery and anaesthesia. Surgical patients with ITP had a higher risk of postoperative death (odds ratio (OR) 1·89, 95 per cent confidence interval 1·57 to 2·27), and overall postoperative complications (OR 1·47, 1·39 to 1·56), and increased hospital stay (OR 1·90, 1·80 to 2·01), admission to the intensive care unit (OR 1·73, 1·63 to 1·83) and medical costs (OR 1·89, 1·79 to 1·99). Amount of preoperative platelet and/or red blood cell transfusion, emergency visits and admission to hospital for ITP care were identified as risk factors for adverse postoperative outcomes.
Conclusion
Patients with ITP undergoing surgery are at increased risk of adverse perioperative events, particularly if blood or blood product transfusion are required preoperatively, or the procedure is done as an emergency.
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Affiliation(s)
- C C Chang
- Department of Anaesthesiology, Taipei Medical University Hospital, Taipei, Taiwan
- Department of Anaesthesiology, Taipei Medical University, Taipei, Taiwan
| | - H C Chang
- Department of Anaesthesiology, Taipei Medical University Hospital, Taipei, Taiwan
- Department of Anaesthesiology, Taipei Medical University, Taipei, Taiwan
| | - C H Wu
- Department of Surgery, College of Medicine, Taipei Medical University, Taipei, Taiwan
| | - C Y Chang
- Department of Paediatrics, Division of Paediatric Haematology/Oncology, Taipei Medical University Hospital, and Graduate Institute of Clinical Medicine, College of Medicine, Taipei, Taiwan
| | - C C Liao
- Department of Anaesthesiology, Taipei Medical University Hospital, Taipei, Taiwan
- Department of Anaesthesiology, Taipei Medical University, Taipei, Taiwan
| | - T L Chen
- Department of Anaesthesiology, Taipei Medical University Hospital, Taipei, Taiwan
- Department of Anaesthesiology, Taipei Medical University, Taipei, Taiwan
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Schoenherr JA, Drennan JM, Martinez JS, Chikka MR, Hall MC, Chang HC, Clemens JC. Drosophila activated Cdc42 kinase has an anti-apoptotic function. PLoS Genet 2012; 8:e1002725. [PMID: 22615583 PMCID: PMC3355085 DOI: 10.1371/journal.pgen.1002725] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2011] [Accepted: 04/05/2012] [Indexed: 01/20/2023] Open
Abstract
Activated Cdc42 kinases (Acks) are evolutionarily conserved non-receptor tyrosine kinases. Activating somatic mutations and increased ACK1 protein levels have been found in many types of human cancers and correlate with a poor prognosis. ACK1 is activated by epidermal growth factor (EGF) receptor signaling and functions to regulate EGF receptor turnover. ACK1 has additionally been found to propagate downstream signals through the phosphorylation of cancer relevant substrates. Using Drosophila as a model organism, we have determined that Drosophila Ack possesses potent anti-apoptotic activity that is dependent on Ack kinase activity and is further activated by EGF receptor/Ras signaling. Ack anti-apoptotic signaling does not function through enhancement of EGF stimulated MAP kinase signaling, suggesting that it must function through phosphorylation of some unknown effector. We isolated several putative Drosophila Ack interacting proteins, many being orthologs of previously identified human ACK1 interacting proteins. Two of these interacting proteins, Drk and yorkie, were found to influence Ack signaling. Drk is the Drosophila homolog of GRB2, which is required to couple ACK1 binding to receptor tyrosine kinases. Drk knockdown blocks Ack survival activity, suggesting that Ack localization is important for its pro-survival activity. Yorkie is a transcriptional co-activator that is downstream of the Salvador-Hippo-Warts pathway and promotes transcription of proliferative and anti-apoptotic genes. We find that yorkie and Ack synergistically interact to produce tissue overgrowth and that yorkie loss of function interferes with Ack anti-apoptotic signaling. Our results demonstrate how increased Ack signaling could contribute to cancer when coupled to proliferative signals. A number of recent studies have uncovered an involvement of Ack family members in human cancer. The majority of these studies focus on human ACK1 and suggest that ACK1 regulates diverse cancer-relevant biological functions, including stimulation of proliferation, blocking programmed cell death, and enhancing metastasis. It is unclear from these studies whether these biological outcomes are directly controlled by ACK1 activity or if they are indirect consequences of ACK1 signaling. Using Drosophila as a model organism, our study demonstrates that Ack serves to promote cell survival by blocking programmed cell death: a mechanism of eliminating excess, damaged, or cancerous cells. We further find that Ack activity functions synergistically with cell growth signals to produce massive cellular overgrowth. Our findings define the physiological role of Ack proteins and add further support to the value of Ack family members as therapeutic drug targets for the treatment of cancer.
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Affiliation(s)
- Jessica A. Schoenherr
- Department of Biochemistry, Purdue University, West Lafayette, Indiana, United States of America
| | - J. Michelle Drennan
- Department of Biochemistry, Purdue University, West Lafayette, Indiana, United States of America
| | - Juan S. Martinez
- Department of Biochemistry, Purdue University, West Lafayette, Indiana, United States of America
| | - Madhusudana Rao Chikka
- Department of Biology, Purdue University, West Lafayette, Indiana, United States of America
| | - Mark C. Hall
- Department of Biochemistry, Purdue University, West Lafayette, Indiana, United States of America
| | - Henry C. Chang
- Department of Biology, Purdue University, West Lafayette, Indiana, United States of America
| | - James C. Clemens
- Department of Biochemistry, Purdue University, West Lafayette, Indiana, United States of America
- * E-mail:
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Lai PH, Chang HC, Chuang TC, Chung HW, Li JY, Weng MJ, Fu JH, Wang PC, Li SC, Pan HB. Susceptibility-weighted imaging in patients with pyogenic brain abscesses at 1.5T: characteristics of the abscess capsule. AJNR Am J Neuroradiol 2012; 33:910-4. [PMID: 22282449 DOI: 10.3174/ajnr.a2866] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE SWI is a high-resolution 3D, fully velocity-compensated gradient-echo sequence that uses both magnitude and phase data. The purpose of this study was to investigate the phase behavior of the capsule of pyogenic brain abscesses with noncontrast SWI. MATERIALS AND METHODS Fourteen patients with pyogenic brain abscesses were studied at 1.5T. In all of the patients, SWI images were obtained and reviewed in addition to conventional MR images. Phase values within the abscess capsule were measured and compared with those from the abscess cavities and contralateral normal white matter using 1-way repeated measures ANOVA with post hoc Bonferroni analysis. RESULTS SWI phase images showed mild hypointesity in 6 patients, isointensity in 3 patients, and mixed iso- to mild hypointensity in 5 patients. The means of phase in the cavity, rim of abscesses, and contralateral normal white matter were -7.552 × 10(-3) ± 0.024, -0.105 ± 0.080, and +0.029 ± 0.011 radians, respectively. Post hoc comparisons showed significant differences between any pair of the 3 regions (abscess cavity, rim capsule, and normal white matter) in SWI (all Ps < .005). CONCLUSIONS SWI phase imaging shows evidence of paramagnetic substances in agreement with the presence of free radicals from phagocytosis. SWI may provide additional information valuable in the characterization of pyogenic brain abscesses.
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Affiliation(s)
- P H Lai
- Department of Radiology, Veterans General Hospital-Kaohsiung, 386 Ta-Chung First Rd., Kaohsiung, Taiwan 813, Republic of China.
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Zhou X, Fabian L, Bayraktar JL, Ding HM, Brill JA, Chang HC. Auxilin is required for formation of Golgi-derived clathrin-coated vesicles during Drosophila spermatogenesis. Development 2011; 138:1111-20. [PMID: 21343365 DOI: 10.1242/dev.057422] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Clathrin has previously been implicated in Drosophila male fertility and spermatid individualization. To understand further the role of membrane transport in this process, we analyzed the phenotypes of mutations in Drosophila auxilin (aux), a regulator of clathrin function, in spermatogenesis. Like partial loss-of-function Clathrin heavy chain (Chc) mutants, aux mutant males are sterile and produce no mature sperm. The reproductive defects of aux males were rescued by male germ cell-specific expression of aux, indicating that auxilin function is required autonomously in the germ cells. Furthermore, this rescue depends on both the clathrin-binding and J domains, suggesting that the ability of Aux to bind clathrin and the Hsc70 ATPase is essential for sperm formation. aux mutant spermatids show a deficit in formation of the plasma membrane during elongation, which probably disrupts the subsequent coordinated migration of investment cones during individualization. In wild-type germ cells, GFP-tagged clathrin localized to clusters of vesicular structures near the Golgi. These structures also contained the Golgi-associated clathrin adaptor AP-1, suggesting that they were Golgi-derived. By contrast, in aux mutant cells, clathrin localized to abnormal patches surrounding the Golgi and its colocalization with AP-1 was disrupted. Based on these results, we propose that Golgi-derived clathrin-positive vesicles are normally required for sustaining the plasma membrane increase necessary for spermatid differentiation. Our data suggest that Aux participates in forming these Golgi-derived clathrin-positive vesicles and that Aux, therefore, has a role in the secretory pathway.
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Affiliation(s)
- Xin Zhou
- Department of Biological Sciences, Purdue University, 915 West State Street, West Lafayette, IN 47907-2054, USA
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Burgess J, Jauregui M, Tan J, Rollins J, Lallet S, Leventis PA, Boulianne GL, Chang HC, Le Borgne R, Krämer H, Brill JA. AP-1 and clathrin are essential for secretory granule biogenesis in Drosophila. Mol Biol Cell 2011; 22:2094-105. [PMID: 21490149 PMCID: PMC3113773 DOI: 10.1091/mbc.e11-01-0054] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.2] [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] [Indexed: 11/11/2022] Open
Abstract
Regulated secretion of hormones, digestive enzymes, and other biologically active molecules requires the formation of secretory granules. Clathrin and the clathrin adaptor protein complex 1 (AP-1) are necessary for maturation of exocrine, endocrine, and neuroendocrine secretory granules. However, the initial steps of secretory granule biogenesis are only minimally understood. Powerful genetic approaches available in the fruit fly Drosophila melanogaster were used to investigate the molecular pathway for biogenesis of the mucin-containing "glue granules" that form within epithelial cells of the third-instar larval salivary gland. Clathrin and AP-1 colocalize at the trans-Golgi network (TGN) and clathrin recruitment requires AP-1. Furthermore, clathrin and AP-1 colocalize with secretory cargo at the TGN and on immature granules. Finally, loss of clathrin or AP-1 leads to a profound block in secretory granule formation. These findings establish a novel role for AP-1- and clathrin-dependent trafficking in the biogenesis of mucin-containing secretory granules.
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Affiliation(s)
- Jason Burgess
- Department of Molecular Genetics, University of Toronto, Ontario, Canada
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Abstract
The aim of this study was to purify and identify an antifungal compound from Lactobacillus plantarum AF1, which was isolated from kimchi. The antifungal compound was purified by solid-phase extraction and recycling preparative high-performance liquid chromatography, and its structure was elucidated by using gas chromatography-mass spectrometry (GC-MS). The active compound from L. plantarum AF1 was confirmed to be δ-dodecalactone (molecular weight, 198.3) by comparison of its gas chromatographic retention time with the mass spectrum of standard δ-dodecalactone. The MICs of δ-dodecalactone against various fungi and bacteria ranged from 350 to 6,250 m g/ml. δ-Dodecalactone showed strong antifungal activity against molds Aspergillus flavus, A. fumigatus, A. petrakii, A. ochraceus, A. nidulans, and Penicillium roqueforti. The three tested yeast strains of Candida albicans were more resistant than the molds. Antibacterial activity was evident but less potent than the antifungal activity. δ-Dodecalactone produced pleasurable (fruity) organoleptic characteristics. The results indicate the potential of the δ-dodecalactone produced by L. plantarum AF1 as a biopreservative and flavoring compound, as well as a biosafe remedy for candidiasis.
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Affiliation(s)
- E J Yang
- Department of Food and Nutrition, Kimchi Research Center, Chosun University, 375 Seosuk-dong, Dong-gu, Gwangju 501-759, Republic of Korea
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Zhou X, Fabian L, Bayraktar JL, Ding HM, Brill JA, Chang HC. Auxilin is required for formation of Golgi-derived clathrin-coated vesicles during Drosophila spermatogenesis. J Cell Sci 2011. [DOI: 10.1242/jcs.088567] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Chang HC, Chen ST, Chien SY, Kuo SJ, Tsai HT, Chen DR. Capsaicin may induce breast cancer cell death through apoptosis-inducing factor involving mitochondrial dysfunction. Hum Exp Toxicol 2011; 30:1657-65. [DOI: 10.1177/0960327110396530] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The majority of breast cancer patients are resistant to chemotherapy or radiotherapy due to the down-regulation or lack of caspase-3 expression. Capsaicin was found to inhibit cancer cell growth in caspase-3-deficient human breast cancer cells. This study aimed to investigate the growth-inhibitive effect of capsaicin and its mechanisms in human breast cancer cell lines, MCF-7 and BT-20. The results showed that cell viability decreased in a dose-dependent manner in both the caspase-3-deficient and non-deficient cells through inducing cell apoptosis and arresting the cell cycle in the S phase. Capsaicin significantly decreased mitochondria membrane potential, induced the cleavage of PARP-1, and decreased procaspase-7 expression in both cells. Apoptosis-inducing factor (AIF) was distinctly released from mitochondria and translocated into the cytoplasm and nucleus in MCF-7 cells (52.9%), but not in BT-20 cells (2%) after treatment with 200 μM of capsaicin for 24 hours. Capsaicin inhibited breast cancer cell growth through inducing cell apoptosis and cell cycle arrest in the S phase. This apoptotic effect could be induced through the mitochondrial pathway, and PARP-1 subsequently cleaved by activation of caspase-7. The application of capsaicin in clinical therapy could be useful for breast cancer patients.
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Affiliation(s)
- HC Chang
- Department of Surgery, Changhua Christian Hospital, Changhua, Taiwan
| | - ST Chen
- Department of Surgery, Changhua Christian Hospital, Changhua, Taiwan
| | - SY Chien
- Department of Pharmacy, Changhua Christian Hospital, Changhua, Taiwan
- College of Health Care and Management, Chung Shan Medical University, Taichung, Taiwan
| | - SJ Kuo
- Department of Surgery, Changhua Christian Hospital, Changhua, Taiwan
- College of Health Care and Management, Chung Shan Medical University, Taichung, Taiwan
- Comprehensive Breast Cancer Center, Changhua Christian Hospital, Changhua, Taiwan
| | - HT Tsai
- School of Nursing, Chung Shan Medical University, Taichung, Taiwan
- Department of Nursing, Chung Shan Medical University Hospital, Taichung, Taiwan
| | - DR Chen
- Department of Surgery, Changhua Christian Hospital, Changhua, Taiwan
- Comprehensive Breast Cancer Center, Changhua Christian Hospital, Changhua, Taiwan
- School of Medicine, Chung Shan Medical University, Taichung, Taiwan
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Chang YC, Hung WT, Chang YC, Chang HC, Wu CL, Chiang AS, Jackson GR, Sang TK. Pathogenic VCP/TER94 alleles are dominant actives and contribute to neurodegeneration by altering cellular ATP level in a Drosophila IBMPFD model. PLoS Genet 2011; 7:e1001288. [PMID: 21304887 PMCID: PMC3033380 DOI: 10.1371/journal.pgen.1001288] [Citation(s) in RCA: 48] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2010] [Accepted: 12/30/2010] [Indexed: 11/18/2022] Open
Abstract
Inclusion body myopathy with Paget's disease of bone and frontotemporal dementia (IBMPFD) is caused by mutations in Valosin-containing protein (VCP), a hexameric AAA ATPase that participates in a variety of cellular processes such as protein degradation, organelle biogenesis, and cell-cycle regulation. To understand how VCP mutations cause IBMPFD, we have established a Drosophila model by overexpressing TER94 (the sole Drosophila VCP ortholog) carrying mutations analogous to those implicated in IBMPFD. Expression of these TER94 mutants in muscle and nervous systems causes tissue degeneration, recapitulating the pathogenic phenotypes in IBMPFD patients. TER94-induced neurodegenerative defects are enhanced by elevated expression of wild-type TER94, suggesting that the pathogenic alleles are dominant active mutations. This conclusion is further supported by the observation that TER94-induced neurodegenerative defects require the formation of hexamer complex, a prerequisite for a functional AAA ATPase. Surprisingly, while disruptions of the ubiquitin-proteasome system (UPS) and the ER-associated degradation (ERAD) have been implicated as causes for VCP-induced tissue degeneration, these processes are not significantly affected in our fly model. Instead, the neurodegenerative defect of TER94 mutants seems sensitive to the level of cellular ATP. We show that increasing cellular ATP by independent mechanisms could suppress the phenotypes of TER94 mutants. Conversely, decreasing cellular ATP would enhance the TER94 mutant phenotypes. Taken together, our analyses have defined the nature of IBMPFD-causing VCP mutations and made an unexpected link between cellular ATP level and IBMPFD pathogenesis.
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Affiliation(s)
- Ya-Chu Chang
- Institute of Biotechnology, Department of Life Science, National Tsing Hua University, Hsinchu, Taiwan
| | - Wan-Tzu Hung
- Institute of Biotechnology, Department of Life Science, National Tsing Hua University, Hsinchu, Taiwan
| | - Yun-Chin Chang
- Institute of Biotechnology, Department of Life Science, National Tsing Hua University, Hsinchu, Taiwan
| | - Henry C. Chang
- Department of Biological Sciences, Purdue University, West Lafayette, Indiana, United States of America
| | - Chia-Lin Wu
- Institute of Biotechnology, Department of Life Science, National Tsing Hua University, Hsinchu, Taiwan
- Brain Research Center, National Tsing Hua University, Hsinchu, Taiwan
| | - Ann-Shyn Chiang
- Institute of Biotechnology, Department of Life Science, National Tsing Hua University, Hsinchu, Taiwan
- Brain Research Center, National Tsing Hua University, Hsinchu, Taiwan
| | - George R. Jackson
- Department of Neurology, Neuroscience, and Cell Biology, University of Texas Medical Branch, Galveston, Texas, United States of America
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, Texas, United States of America
- Mitchell Center for Neurodegenerative Diseases, University of Texas Medical Branch, Galveston, Texas, United States of America
| | - Tzu-Kang Sang
- Institute of Biotechnology, Department of Life Science, National Tsing Hua University, Hsinchu, Taiwan
- Brain Research Center, National Tsing Hua University, Hsinchu, Taiwan
- * E-mail:
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Chang HC, Chen TH, Lin DL. Forensic Science in Support of Wildlife Conservation Efforts - Developments in Morphological and Chemical Approaches in Taiwan. Forensic Sci Rev 2011; 23:37-54. [PMID: 26231168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Parts from animals that are now endangered species (such as bear bile, rhino horn, and tiger bone) have long been important ingredients of traditional Chinese medicine (TCM). Deeply believing in the potency of these ingredients and coupled with substantial gains in wealth of the population in Taiwan in the 1980s, ugly scenarios came to light. Taiwan quickly became the target of investigation pursued by international wildlife conservationists. To provide scientific bases for the government's investigation efforts, morphological, chemical/physical, and genetic methods were developed to characterize TCM products. This review focuses on Taiwanese scientists' efforts on the following topic matters: (a) morphological approach to identify CITES-listed species from the turtle shells traded in the TCM market; (b) chromatographic and spectrophotometric methods for the identification and differentiation of bile products of different animal origins; and (c) gas chromatography-mass spectrometry method for the analysis of deer musk components and alleged musk products.
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Affiliation(s)
- H C Chang
- School of Chinese Medicine, China Medical University, Taichung City, Taiwan
| | - T H Chen
- Institute of Wildlife Conservation, National Pinging University of Science and Technology, Neipu Hsiang, Pinging Hsien, Taiwan
| | - D L Lin
- Institute of Forensic Medicine, Ministry of Justice, New Taipei City, Taiwan
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Lee JH, Kim TW, Lee H, Chang HC, Kim HY. Determination of microbial diversity in meju, fermented cooked soya beans, using nested PCR-denaturing gradient gel electrophoresis. Lett Appl Microbiol 2010; 51:388-94. [PMID: 20704651 DOI: 10.1111/j.1472-765x.2010.02906.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
AIMS To identify the microbiota in meju, fermented cooked soya beans, that may directly affect the microbial communities of Korean fermented soya bean foods. METHODS AND RESULTS Using conventional bacterial 16S rDNA, bacilli-specific 16S rDNA or fungi 18S rDNA-specific primers, PCR products were amplified through a series of PCRs using the DNA extracted from ten meju samples. The amplicons were analysed using denaturing gradient gel electrophoresis (DGGE), which showed that Enterococcus durans was commonly detected in nine of ten meju samples. Bacillus subtilis was shown to be the major strain of bacilli in the samples tested. Based on the DGGE analysis of fungi in meju, we determined that Absidia corymbifera, Aspergillus sp. and Candida rugosa were the main fungi in the tested samples. CONCLUSIONS A variety of bacterial and fungal micro-organisms were identified in meju samples, in addition to the micro-organisms already known to be present. SIGNIFICANCE AND IMPACT OF THE STUDY This is the first report showing the differences and similarities in the populations of micro-organisms in meju samples using nested PCR-DGGE, a culture-independent method. The results may be applicable to the development of improved meju, in which the indigenous micro-organisms required for fermentation can be standardized.
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MESH Headings
- Bacteria/classification
- Bacteria/genetics
- Bacteria/isolation & purification
- Cooking
- DNA, Bacterial/analysis
- DNA, Bacterial/isolation & purification
- DNA, Fungal/analysis
- DNA, Fungal/isolation & purification
- DNA, Ribosomal/genetics
- Denaturing Gradient Gel Electrophoresis/methods
- Ecosystem
- Fermentation
- Fungi/classification
- Fungi/genetics
- Fungi/isolation & purification
- Polymerase Chain Reaction/methods
- RNA, Ribosomal, 16S/genetics
- RNA, Ribosomal, 18S/genetics
- Republic of Korea
- Sequence Analysis, DNA
- Glycine max/microbiology
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Affiliation(s)
- J-H Lee
- Institute of Life Sciences & Resources and Graduate School of Biotechnology, Kyung Hee University, Yongin, Korea
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Yang EJ, Chang HC. Purification of a new antifungal compound produced by Lactobacillus plantarum AF1 isolated from kimchi. Int J Food Microbiol 2010; 139:56-63. [PMID: 20226553 DOI: 10.1016/j.ijfoodmicro.2010.02.012] [Citation(s) in RCA: 147] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2009] [Revised: 01/29/2010] [Accepted: 02/13/2010] [Indexed: 11/20/2022]
Abstract
The aim of this study was to purify and to identify an antifungal compound of Lactobacillus plantarum AF1, which was isolated from kimchi, and to determine if Lb. plantarum AF1 can prevent fungal growth in a particular food model system. The antifungal compound was purified using SPE and recycling prep-HPLC and its structure was elucidated using NMR and ESI-MS. The active compound from Lb. plantarum AF1 is C(12)H(22)N(2)O(2), 3,6-bis(2-methylpropyl)-2,5-piperazinedion has a molecular mass of 226. This is a new antifungal compound produced by lactic acid bacteria (LAB). To investigate the potential application of the antifungal compound to eliminate fungal spoilage in food and feed, soybean was used as a model. White mycelia and dark green spores of Aspergillus flavus ATCC 22546 were observed in the control soybeans after 1 to 2days incubation. However, fungal growth was not observed in the soybeans treated with a 4-fold concentrated supernatant of Lb. plantarum AF1 culture, even after 2days. The end products produced from kimchi LAB, like 3,6-bis(2-methylpropyl)-2,5-piperazinedion identified in this study, may be a promising alternative to chemical preservatives as a potential biopreservative which prevent fungal spoilage and mycotoxin formation in food and feed.
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Affiliation(s)
- E J Yang
- Department of Food and Nutrition, Chosun University, Gwangju 501-759, Republic of Korea
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Bai T, Seebald JL, Kim KE, Ding HM, Szeto DP, Chang HC. Disruption of zebrafish cyclin G-associated kinase (GAK) function impairs the expression of Notch-dependent genes during neurogenesis and causes defects in neuronal development. BMC Dev Biol 2010; 10:7. [PMID: 20082716 PMCID: PMC2821301 DOI: 10.1186/1471-213x-10-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/25/2009] [Accepted: 01/18/2010] [Indexed: 12/19/2022]
Abstract
Background The J-domain-containing protein auxilin, a critical regulator in clathrin-mediated transport, has been implicated in Drosophila Notch signaling. To ask if this role of auxilin is conserved and whether auxilin has additional roles in development, we have investigated the functions of auxilin orthologs in zebrafish. Results Like mammals, zebrafish has two distinct auxilin-like molecules, auxilin and cyclin G-associated kinase (GAK), differing in their domain structures and expression patterns. Both zebrafish auxilin and GAK can functionally substitute for the Drosophila auxilin, suggesting that they have overlapping molecular functions. Still, they are not completely redundant, as morpholino-mediated knockdown of the ubiquitously expressed GAK alone can increase the specification of neuronal cells, a known Notch-dependent process, and decrease the expression of Her4, a Notch target gene. Furthermore, inhibition of GAK function caused an elevated level of apoptosis in neural tissues, resulting in severe degeneration of neural structures. Conclusion In support of the notion that endocytosis plays important roles in Notch signaling, inhibition of zebrafish GAK function affects embryonic neuronal cell specification and Her4 expression. In addition, our analysis suggests that zebrafish GAK has at least two functions during the development of neural tissues: an early Notch-dependent role in neuronal patterning and a late role in maintaining the survival of neural cells.
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Affiliation(s)
- Ting Bai
- Department of Biological Sciences, Purdue University, 915 W, State St,, West Lafayette, Indiana 47907-2054, USA
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Cheli VT, Daniels RW, Godoy R, Hoyle DJ, Kandachar V, Starcevic M, Martinez-Agosto JA, Poole S, DiAntonio A, Lloyd VK, Chang HC, Krantz DE, Dell'Angelica EC. Genetic modifiers of abnormal organelle biogenesis in a Drosophila model of BLOC-1 deficiency. Hum Mol Genet 2009; 19:861-78. [PMID: 20015953 DOI: 10.1093/hmg/ddp555] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Biogenesis of lysosome-related organelles complex 1 (BLOC-1) is a protein complex formed by the products of eight distinct genes. Loss-of-function mutations in two of these genes, DTNBP1 and BLOC1S3, cause Hermansky-Pudlak syndrome, a human disorder characterized by defective biogenesis of lysosome-related organelles. In addition, haplotype variants within the same two genes have been postulated to increase the risk of developing schizophrenia. However, the molecular function of BLOC-1 remains unknown. Here, we have generated a fly model of BLOC-1 deficiency. Mutant flies lacking the conserved Blos1 subunit displayed eye pigmentation defects due to abnormal pigment granules, which are lysosome-related organelles, as well as abnormal glutamatergic transmission and behavior. Epistatic analyses revealed that BLOC-1 function in pigment granule biogenesis requires the activities of BLOC-2 and a putative Rab guanine-nucleotide-exchange factor named Claret. The eye pigmentation phenotype was modified by misexpression of proteins involved in intracellular protein trafficking; in particular, the phenotype was partially ameliorated by Rab11 and strongly enhanced by the clathrin-disassembly factor, Auxilin. These observations validate Drosophila melanogaster as a powerful model for the study of BLOC-1 function and its interactions with modifier genes.
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Affiliation(s)
- Verónica T Cheli
- Department of Human Genetics, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA
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Chung CK, Chang HC, Shih TR, Lin SL, Hsiao EJ, Chen YS, Chang EC, Chen CC, Lin CC. Water-assisted CO(2) laser ablated glass and modified thermal bonding for capillary-driven bio-fluidic application. Biomed Microdevices 2009. [PMID: 19830566 DOI: 10.1007/s10544‐009‐9365‐x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The glass-based microfluidic chip has widely been applied to the lab-on-a-chip for clotting tests. Here, we have demonstrated a capillary driven flow chip using the water-assisted CO(2) laser ablation for crackless fluidic channels and holes as well as the modified low-temperature glass bonding with assistance of adhesive polymer film at 300 degrees Celsius. Effect of water depth on the laser ablation of glass quality was investigated. The surface hydrophilic property of glass and polymer film was measured by static contact angle method for hydrophilicity examination in comparison with the conventional polydimethylsiloxane (PDMS) material. Both low-viscosity deionized water and high-viscosity whole blood were used for testing the capillary-driving flow behavior. The preliminary coagulation testing in the Y-channel chip was also performed using whole blood and CaCl(2) solution. The water-assisted CO(2) laser processing can cool down glass during ablation for less temperature gradient to eliminate the crack. The modified glass bonding can simplify the conventional complex fabrication procedure of glass chips, such as high-temperature bonding, long consuming time and high cost. Moreover, the developed fluidic glass chip has the merit of hydrophilic behavior conquering the problem of traditional hydrophobic recovery of polymer fluidic chips and shows the ability to drive high-viscosity bio-fluids.
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Affiliation(s)
- C K Chung
- Department of Mechanical Engineering, Center for Micro/Nano Science and Technology, National Cheng Kung University, Tainan, Taiwan.
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Chang HC, Cheng HH, Huang CJ, Chen WC, Chen IS, Liu SI, Hsu SS, Chang HT, Wang JK, Lu YC, Chou CT, Jan CR. Safrole-Induced Ca2+Mobilization and Cytotoxicity in Human PC3 Prostate Cancer Cells. J Recept Signal Transduct Res 2008; 26:199-212. [PMID: 16777715 DOI: 10.1080/10799890600662595] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
The effect of the carcinogen safrole on intracellular Ca2+ mobilization and on viability of human PC3 prostate cancer cells was examined. Cytosolic free Ca2+ levels ([Ca2+]i) were measured by using fura-2 as a probe. Safrole at concentrations above 10 microM increased [Ca2+]i in a concentration-dependent manner with an EC50 value of 350 microM. The Ca2+ signal was reduced by more than half after removing extracellular Ca2+ but was unaffected by nifedipine, nicardipine, nimodipine, diltiazem, or verapamil. In Ca2+-free medium, after treatment with 650 microM safrole, 1 microM thapsigargin (an endoplasmic reticulum Ca2+ pump inhibitor) failed to release Ca2+. Neither inhibition of phospholipase C with U73122 nor modulation of protein kinase C activity affected safrole-induced Ca2+ release. Overnight incubation with 0.65-65 microM safrole did not affect cell viability, but incubation with 325-625 microM safrole decreased viability. Collectively, the data suggest that in PC3 cells, safrole induced a [Ca2+]i increase by causing Ca2+ release from the endoplasmic reticulum in a phospholipase C- and protein kinase C-independent fashion, and by inducing Ca2+ influx. Safrole can decrease cell viability in a concentration-dependent manner.
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Affiliation(s)
- H C Chang
- Department of Urology, College of Medicine, National Taiwan University, Taipei, Taiwan
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Maday S, Anderson E, Chang HC, Shorter J, Satoh A, Sfakianos J, Fölsch H, Anderson JM, Walther Z, Mellman I. A PDZ-binding motif controls basolateral targeting of syndecan-1 along the biosynthetic pathway in polarized epithelial cells. Traffic 2008; 9:1915-24. [PMID: 18764819 DOI: 10.1111/j.1600-0854.2008.00805.x] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The cell surface proteoglycan, syndecan-1, is essential for normal epithelial morphology and function. Syndecan-1 is selectively localized to the basolateral domain of polarized epithelial cells and interacts with cytosolic PDZ (PSD-95, discs large, ZO-1) domain-containing proteins. Here, we show that the polarity of syndecan-1 is determined by its type II PDZ-binding motif. Mutations within the PDZ-binding motif lead to the mislocalization of syndecan-1 to the apical surface. In contrast to previous examples, however, PDZ-binding motif-dependent polarity is not determined by retention at the basolateral surface but rather by polarized sorting prior to syndecan-1's arrival at the plasma membrane. Although none of the four known PDZ-binding partners of syndecan-1 appears to control basolateral localization, our results show that the PDZ-binding motif of syndecan-1 is decoded along the biosynthetic pathway establishing a potential role for PDZ-mediated interactions in polarized sorting.
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Affiliation(s)
- Sandra Maday
- Department of Cell Biology, Ludwig Institute for Cancer Research, Yale University School of Medicine, New Haven, CT 06520, USA
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Kandachar V, Bai T, Chang HC. The clathrin-binding motif and the J-domain of Drosophila Auxilin are essential for facilitating Notch ligand endocytosis. BMC Dev Biol 2008; 8:50. [PMID: 18466624 PMCID: PMC2391152 DOI: 10.1186/1471-213x-8-50] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/01/2007] [Accepted: 05/08/2008] [Indexed: 11/24/2022]
Abstract
Background Ligand endocytosis plays a critical role in regulating the activity of the Notch pathway. The Drosophila homolog of auxilin (dAux), a J-domain-containing protein best known for its role in the disassembly of clathrin coats from clathrin-coated vesicles, has recently been implicated in Notch signaling, although its exact mechanism remains poorly understood. Results To understand the role of auxilin in Notch ligand endocytosis, we have analyzed several point mutations affecting specific domains of dAux. In agreement with previous work, analysis using these stronger dAux alleles shows that dAux is required for several Notch-dependent processes, and its function during Notch signaling is required in the signaling cells. In support of the genetic evidences, the level of Delta appears elevated in dAux deficient cells, suggesting that the endocytosis of Notch ligand is disrupted. Deletion analysis shows that the clathrin-binding motif and the J-domain, when over-expressed, are sufficient for rescuing dAux phenotypes, implying that the recruitment of Hsc70 to clathrin is a critical role for dAux. However, surface labeling experiment shows that, in dAux mutant cells, Delta accumulates at the cell surface. In dAux mutant cells, clathrin appears to form large aggregates, although Delta is not enriched in these aberrant clathrin-positive structures. Conclusion Our data suggest that dAux mutations inhibit Notch ligand internalization at an early step during clathrin-mediated endocytosis, before the disassembly of clathrin-coated vesicles. Further, the inhibition of ligand endocytosis in dAux mutant cells possibly occurs due to depletion of cytosolic pools of clathrin via the formation of clathrin aggregates. Together, our observations argue that ligand endocytosis is critical for Notch signaling and auxilin participates in Notch signaling by facilitating ligand internalization.
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Affiliation(s)
- Vasundhara Kandachar
- Department of Biological Sciences, Purdue University, 915 West State Street, West Lafayette, Indiana 47907-2054, USA.
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Liu SI, Cheng HH, Huang CJ, Chang HC, Chen WC, Chen IS, Hsu SS, Chang HT, Huang JK, Chen JS, Lu YC, Jan CR. Melittin-induced [Ca2+]i increases and subsequent death in canine renal tubular cells. Hum Exp Toxicol 2008; 27:417-24. [DOI: 10.1177/0960327108094606] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The effect of melittin on cytosolic free Ca2+ concentration ([Ca2+]i) and viability is largely unknown. This study examined whether melittin alters Ca2+ levels and causes Ca2+-dependent cell death in Madin-Darby canine kidney (MDCK) cells. [Ca2+]i and cell death were measured using the fluorescent dyes fura-2 and WST-1 respectively. Melittin at concentrations above 0.5 μM increased [Ca2+]i in a concentration-dependent manner. The Ca2+ signal was reduced by 75% by removing extracellular Ca2+. The melittin-induced Ca2+ influx was also implicated by melittin-caused Mn2+ influx. After pretreatment with 1 μM thapsigargin (an endoplasmic reticulum Ca2+ pump inhibitor), melittin-induced Ca2+ release was inhibited; and conversely, melittin pretreatment abolished thapsigargin-induced Ca2+ release. At concentrations of 0.5–20 μM, melittin killed cells in a concentration-dependent manner. The cytotoxic effect of 0.5 μM melittin was nearly completely reversed by prechelating cytosolic Ca2+ with BAPTA. Melittin at 0.5–2 μM caused apoptosis as assessed by flow cytometry of propidium iodide staining. Collectively, in MDCK cells, melittin induced a [Ca2+]i rise by causing Ca2+ release from endoplasmic reticulum and Ca2+ influx from extracellular space. Furthermore, melittin can cause Ca2+-dependent cytotoxicity in a concentration-dependent manner.
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Affiliation(s)
- SI Liu
- Department of Surgery, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
| | - HH Cheng
- Section of Allergy, Immunology and Rheumatology, Chi-Mei Medical Center, Tainan, Taiwan
| | - CJ Huang
- Department of Psychiatry, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan; Department of Psychiatry, Tian-Sheng Memorial Hospital, Ping-Tong, Taiwan
| | - HC Chang
- Department of Urology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - WC Chen
- Department of Surgery, Ping Tung Christian Hospital, Ping Tung, Taiwan
| | - IS Chen
- Department of Surgery, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
| | - SS Hsu
- Department of Surgery, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
| | - HT Chang
- Department of Surgery, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
| | - JK Huang
- Department of Surgery, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
| | - JS Chen
- Department of Surgery, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
| | - YC Lu
- Department of Orthopaedic Surgery, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
| | - CR Jan
- Department of Medical Education and Research, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
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Chang HC, Poh SY, Seah SC, Chua DTC, Cha BK, Low CO. Fragment-specific fracture fixation and double-column plating of unstable distal radial fractures using AO mini-fragment implants and Kirschner wires. Injury 2007; 38:1259-67. [PMID: 17631882 DOI: 10.1016/j.injury.2007.03.024] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [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: 11/14/2006] [Revised: 03/06/2007] [Accepted: 03/09/2007] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To evaluate the efficacy of AO mini-fragment implants and 1.25-mm Kirschner wires using fragment-specific fracture fixation and double-column plating for displaced or unstable distal radial fractures. DESIGN prospective and consecutive. SETTING level II trauma hospital. PARTICIPANTS 28 people with 30 fractures and an average follow-up of 21.1 (range 12-41) months, treated with fragment-specific fracture fixation. OUTCOME MEASUREMENTS anatomical assessment using anteroposterior and lateral radiographs, graded according to Sarmiento's modification of Lidstrom's scoring system. CLINICAL OUTCOME ASSESSMENT: DASH and Modified Gartland and Werley scores. RESULTS There were 24 excellent and 6 good radiological results. Final mean grip strength was 83% of uninjured side, and mean wrist range of motion was 61 degrees dorsiflexion, 54 degrees palmar flexion, 85 degrees supination and 83 degrees pronation. Gartland and Werley's demerit point system revealed 13 (43%) excellent, 12 (40%) good, 5 (17%) fair and no poor results. The mean DASH score was 18, with a standard deviation of +/-18. CONCLUSION This fixation method is a reliable and low-cost alternative with good clinical and anatomical results, particularly useful in open reduction and internal fixation of comminuted intra-articular distal radial fractures.
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Affiliation(s)
- H C Chang
- Department of Orthopaedic Surgery, Changi General Hospital, Singapore 529889, Singapore.
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Chang JY, Lee HJ, Chang HC. Identification of the agent from Lactobacillus plantarum KFRI464 that enhances bacteriocin production by Leuconostoc citreum GJ7. J Appl Microbiol 2007; 103:2504-15. [PMID: 17850309 DOI: 10.1111/j.1365-2672.2007.03543.x] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.0] [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: 11/28/2022]
Abstract
AIM To provide evidence that the production of bacteriocin by lactic acid bacteria can be enhanced by the presence of a bacteriocin-sensitive strain and identify the agent that is responsible for enhancing bacteriocin production. METHODS AND RESULTS One bacteriocin-producing lactic acid bacterium was isolated from kimchi. The strain GJ7 was designated as Leuconostoc citreum GJ7 based on Gram staining, biochemical properties, and 16S rRNA gene sequencing. The isolate produced a heat- and pH-stable bacteriocin (kimchicin GJ7), which has antagonistic activity against a broad spectrum of micro-organisms. Tricine-sodium dodecyl sulfate-polyacrylamide gel electrophoresis of purified kimchicin GJ7 showed a single band of molecular weight c. 3500 Da. Cultures of Leuc. citreum GJ7 in the presence of thermally inactivated kimchicin GJ7-sensitive strains, Lactobacillus plantarum KFRI 464, Lactobacillus delbrueckii KFRI 347, or Leuconostoc mesenteroides KCTC 1628, increased bacteriocin production. This inducing factor was characterized and purified from Lact. plantarum KFRI 464, which showed the greatest enhancement of kimchicin GJ7 activity. The inducing factor was purified using a DEAE (diethyl aminoethyl)-Sephacel column and high-performance liquid chromatography, and yielded a single band of c. 6500 Da. N-terminal sequencing of the inducing factor identified 16 amino acids. The N-terminal sequence of the inducing factor was synthesized and examined for the induction of kimchicin GJ7 activity, and was found to induce activity, but at a level about 10% lower than that of the entire molecule. CONCLUSIONS The presence of a bacteriocin-sensitive strain, Lact. plantarum KFRI 464, acts as an environmental stimulus to activate the production of kimchicin GJ7 by Leuc. citreum GJ7. The inducing factor from Lact. plantarum KFRI 464 is highly homologous to the 30S ribosomal protein S16 from various micro-organisms. The N-terminal sequence of the inducing factor examined in this study is a very important sequence related to the inducing activity. Nevertheless, the inducing factor may not be part of the ribosomal protein S16 itself. SIGNIFICANCE AND IMPACT OF THE STUDY We believe that the present study is the first to identify an agent that is produced by one micro-organism and influences bacteriocin production in another. The bacteriocin-enhancing system described in this study could be effectively used to control the growth of other micro-organisms (sensitive cells) in food systems. Moreover, this enhancement of bacteriocin production can be applied usefully in industrial production of natural food preservatives.
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Affiliation(s)
- J Y Chang
- Department of Food and Nutrition, Chosun University, 375 Seosukdong, Donggu, Gwangju, Republic of Korea
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Abstract
PURPOSE To evaluate outcomes of arthroscopic subacromial decompression for stage-II impingement. METHODS Records of 42 consecutive patients with stage-II impingement treated by arthroscopic subacromial decompression from January 2000 to February 2002 were reviewed. Clinical outcomes were measured using the UCLA shoulder rating scale, and radiological outcomes using anteroposterior and supraspinatus outlet shoulder radiographs. RESULTS The mean follow-up period was 14.6 (range, 12-30) months. Using the UCLA scale, 14 (33%) patients had an excellent result, 21 (50%) had a good result, 4 (10%) had a fair result, and 3 (7%) had a poor result. Mean component scores for the UCLA scale were: 8.0 for pain, 8.8 for function, 4.5 for forward flexion, and 4.5 for strength. The mean extent of resection was 2.9 mm in the anteroposterior and 2.0 mm in the supraspinatus outlet radiographs. There was no correlation between the extent of acromial resection and the UCLA shoulder rating scores. CONCLUSION Short-term results of arthroscopic subacromial decompression for stage-II impingement are favourable.
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Affiliation(s)
- K K Lim
- Department of Orthopaedic Surgery, Changi General Hospital, Singapore
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Hagedorn EJ, Bayraktar JL, Kandachar VR, Bai T, Englert DM, Chang HC. Drosophila melanogaster auxilin regulates the internalization of Delta to control activity of the Notch signaling pathway. ACTA ACUST UNITED AC 2006; 173:443-52. [PMID: 16682530 PMCID: PMC2063844 DOI: 10.1083/jcb.200602054] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We have isolated mutations in the Drosophila melanogaster homologue of auxilin, a J-domain-containing protein known to cooperate with Hsc70 in the disassembly of clathrin coats from clathrin-coated vesicles in vitro. Consistent with this biochemical role, animals with reduced auxilin function exhibit genetic interactions with Hsc70 and clathrin. Interestingly, the auxilin mutations interact specifically with Notch and disrupt several Notch-mediated processes. Genetic evidence places auxilin function in the signal-sending cells, upstream of Notch receptor activation, suggesting that the relevant cargo for this auxilin-mediated endocytosis is the Notch ligand Delta. Indeed, the localization of Delta protein is disrupted in auxilin mutant tissues. Thus, our data suggest that auxilin is an integral component of the Notch signaling pathway, participating in the ubiquitin-dependent endocytosis of Delta. Furthermore, the fact that auxilin is required for Notch signaling suggests that ligand endocytosis in the signal-sending cells needs to proceed past coat disassembly to activate Notch.
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MESH Headings
- Animals
- Auxilins/genetics
- Auxilins/physiology
- Body Patterning/genetics
- Body Patterning/physiology
- Clathrin/genetics
- Clathrin/metabolism
- Drosophila melanogaster/embryology
- Drosophila melanogaster/genetics
- Drosophila melanogaster/physiology
- Endocytosis/genetics
- Endocytosis/physiology
- ErbB Receptors/genetics
- ErbB Receptors/physiology
- Eye Abnormalities/genetics
- Eye Abnormalities/ultrastructure
- Gene Expression Regulation, Developmental
- Genotype
- HSC70 Heat-Shock Proteins/genetics
- HSC70 Heat-Shock Proteins/metabolism
- Intracellular Signaling Peptides and Proteins
- Membrane Proteins/genetics
- Membrane Proteins/metabolism
- Microscopy, Electron, Scanning
- Mutation/genetics
- Nervous System/embryology
- Nervous System/metabolism
- Phenotype
- Photoreceptor Cells, Invertebrate/embryology
- Photoreceptor Cells, Invertebrate/metabolism
- RNA, Small Interfering/genetics
- Receptors, Notch/genetics
- Receptors, Notch/physiology
- Signal Transduction/genetics
- Signal Transduction/physiology
- Wings, Animal/embryology
- Wings, Animal/metabolism
- Wings, Animal/ultrastructure
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Affiliation(s)
- Elliott J Hagedorn
- Department of Biological Sciences, Purdue University, West Lafayette, IN 47907, USA
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Affiliation(s)
- H C Chang
- Department of Medicine, Peiping Union Medical College, Peiping
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48
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Affiliation(s)
- H C Chang
- Medical Clinic of the Johns Hopkins Hospital and University, Baltimore
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49
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Affiliation(s)
- H C Chang
- Department of Medicine, Peiping Union Medical College, Peiping, China
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Affiliation(s)
- H C Chang
- Medical Clinic of the Johns Hopkins Hospital and University, Baltimore
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