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Featured researches published by Chun-Nan Chen.


European Journal of Radiology | 2012

Transcutaneous ultrasound for evaluation of vocal fold movement in patients with thyroid disease

Cheng-Ping Wang; Tseng-Cheng Chen; Tsung-Lin Yang; Chun-Nan Chen; Chin-Fon Lin; Pei-Jen Lou; Ya-Ling Hu; Ming-Jium Shieh; Fon-Jou Hsieh; Tzu-Yu Hsiao; Jenq-Yuh Ko

BACKGROUND Preoperative evaluation of recurrent laryngeal nerve function is important in the context of thyroid surgery. Transcutaneous ultrasound may be useful to visualize vocal fold movement when evaluating thyroid disease. METHODS A 7-18 MHz linear array transducer was placed transversely on the midline of the thyroid cartilage at the anterior neck of patients with thyroid disease. The gray-scale technique was used, with the scan setting for the thyroid gland. RESULTS Between August 2008 and March 2010, 705 patients, including 672 patients with normal vocal fold movement and 33 patients with vocal fold paralysis were enrolled. They included 159 male and 546 female patients. Their ages ranged from 10 to 88 years. Vocal fold movement could be seen by ultrasound in 614 (87%) patients, including 589 (88%) patients with normal vocal fold movement and 25 (76%) patients with vocal fold paralysis (p=0.06). The mean age of patients with visible and invisible vocal fold movement was 46.6 and 57.9 years old, respectively (p=0.001). Ultrasound was able to see vocal fold movement in 533 (98%) female patients but only in 81 (51%) male patients (p=0.001). Among the patients with vocal fold paralysis, ultrasound revealed palsied vocal folds in 17 of 18 (94%) female patients but in only 8 of 15 (53%) male patients (p=0.01). CONCLUSION Transcutaneous ultrasound represents an alternative tool to evaluate vocal fold movement for more than 85% of patients with thyroid disease, including more than 90% of female patients and about half of male patients.


Oral Oncology | 2013

The clinical predictive factors for subsequent distant metastasis in patients with locoregionally advanced oral squamous cell carcinoma

Tseng-Cheng Chen; Chun-Wei Hsu; Pei-Jen Lou; Jeng-Yuh Ko; Tsung-Lin Yang; Chun-Nan Chen; Yih-Leong Chang; Cheng-Ping Wang

OBJECTIVES Only a small portion of the patients with locoregionally advanced oral squamous cell carcinoma (OSCC) experience subsequent distant metastasis. This study is to evaluate the occurrence of distant metastasis after curative treatment and to explore the predictive factors for subsequent distant metastasis in patients with locoregionally advanced OSCC. MATERIALS AND METHODS The medical records of all patients with locoregionally advanced OSCC without distant metastasis at the time of diagnosis (AJCC stage III, IV but not IVC) who underwent curative surgery with or without adjuvant radiation between 2004 and 2009 were retrospectively reviewed. RESULTS A total of 628 patients were enrolled, including 562 male and 66 female patients. The 5-year distant metastasis rate was 13.2%. The 5-year disease-free and overall survival rates were 57.0% and 60.3%, respectively. Multivariate analyses revealed that poorly differentiated tumors (HR=2.3 (1.16-4.53), p=0.02) and contralateral neck metastasis (HR=7.55 (3.20-17.83), p<0.001) were independent adverse factors for distant metastasis-free survival. The 5-year distant metastasis rates of 447 patients with well-differentiated tumors, 140 patients with moderately differentiated tumors and 41 patients with poorly differentiated tumors were 12.1%, 18.2%, and 34.1%, respectively. The 5-year distant metastasis rates of 227 patients without neck metastasis, 350 patients with ipsilateral neck metastasis and 51 patients with contralateral neck metastasis were 6.7%, 15.1%, and 55.3%, respectively. CONCLUSIONS Poorly differentiated tumors and contralateral neck metastasis were independent factors for subsequent distant metastasis in patients with locoregionally advanced OSCC.


Acta Biomaterialia | 2013

Controlling branching structure formation of the salivary gland by the degree of chitosan deacetylation.

Ya-Chuan Hsiao; Chun-Nan Chen; You-Tzung Chen; Tsung-Lin Yang

The salivary gland is characterized by ramified epithelial branches, a specific tissue structure responsible for saliva production and regulation. To regenerate the salivary gland function, it is important to establish the tissue structure. Chitosan is a deacetylated derivative of chitin with wide biomedical applications. Because of its deacetylated nature, chitosan has different properties when prepared with different degrees of deacetylation (DDA). However, the impact of chitosan DDA on the effect of regulating tissue structure formation remains unexplored. In this study, the embryonic murine submandibular gland (SMG) was used as a model to investigate the role of chitosan DDA in regulating tissue structure formation of the salivary gland. When chitin substrates with different DDA were used, the branching numbers of cultured SMG explants changed. Similar effects were observed in the culture with chitosan prepared using different degrees of acetylation. The mRNA expressions of type I and type III collagen were elevated in SMG explants with enhanced branching morphogenesis, as was the protein level. In addition to the amounts of collagen, type I and type III collagen fibers were spatially present in the epithelial-mesenchymal junction of developing branches in the culture with chitosan of a specific range of DDA. The branch-promoting effect of chitosan DDA was abolished when SMG explants were treated with collagenase, both early in the stage of branch initiation and with the establishment of the branching structure. The branch-promoting effect of chitosan DDA disappeared when antisense oligonucleotides were applied to specifically block type III collagen. This study demonstrates for the first time that DDA of chitosan affects tissue structure formation. The different proportions of side-chain components of chitin derivatives regulate structural formation of cultured SMG, indicating that DDA is an important parameter using chitosan as a biomaterial for tissue structure formation of the salivary glands.


PLOS ONE | 2014

Diagnosis of Kikuchi-Fujimoto disease: a comparison between open biopsy and minimally invasive ultrasound-guided core biopsy.

Shan-Chi Yu; Chun-Nan Chen; Hsin-I Huang; Tseng-Cheng Chen; Cheng-Ping Wang; Pei-Jen Lou; Jenq-Yuh Ko; Tzu-Yu Hsiao; Tsung-Lin Yang

Kikuchi-Fujimoto disease (KFD) is a self-limited disease without any need of surgical treatments. Sampling of tissue is the only invasive procedure during the clinical course. However, the standard sampling procedure with accuracy, minimal invasiveness, and esthetic maintenance has not been established yet. In this study, a retrospective review of clinical utility and pathological presentations of the ultrasound-guided core biopsy (USCB) and the open biopsy (OB) in consecutive KFD patients. From 2010 to 2012, 34 consecutive patients were enrolled. USCB was performed in 11 patients, and OB was done in 26 patients. KFD was confirmed in 82% cases by USCB. Similar pathological presentations were found both in the specimens of USCB and OB. In the three patients who had received both USCB and OB, KFD was confirmed by USCB in one case, while two by OB. Sampling errors were found both in USCB and OB. For diagnosing KFD, USCB can serve as the first-line diagnostic tool. OB can be applied only in the failed cases of USCB.


Clinical Otolaryngology | 2016

Application of ultrasound-guided core biopsy as a novel diagnostic tool for base of tongue cancer: Our experiences with ten patients.

Chun-Nan Chen; Che-Yi Lin; Jenq-Yuh Ko; Pei-Jen Lou; Cheng-Ping Wang; Tseng-Cheng Chen; Tzu-Yu Hsiao; Tsung-Lin Yang

*Department of Otolaryngology, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Department of Otolaryngology, National Taiwan University Hospital Hsin-Chu Branch, Hsin-Chu, Graduate Institute of Clinical Medicine, National TaiwanUniversity College ofMedicine, Taipei, Department of Otolaryngology, National TaiwanUniversity Hospital Yun-Lin Branch, Yun-Lin, Research Center for Developmental Biology and Regenerative Medicine, National Taiwan University, Taipei, Taiwan


Optics Express | 2008

Creating optical anisotropy of CdSe/ZnS quantum dots by coupling to surface plasmon polariton resonance of a metal grating

Huai-Lei Fu; Chun-Nan Chen; Cih-Su Wang; T. T. Chen; Yang-Fang Chen

An efficient method that can be used to control the optical anisotropy of CdSe/ZnS quantum dots by coupling to the surface plasmon polariton resonance of a metal grating has been demonstrated. It is found that the unpolarized emission and Raman scattering signals arising from CdSe/ZnS quantum dots can be manipulated and exhibit a strong anisotropic behavior based upon our strategy. The optical anisotropy is interpreted in terms of the coupling between the directional surface plasmon of metal grating and the emitted light beam of quantum dots. Due to the importance of quantum dots in optoelectronic devices, our new approach should be useful for future application.


Data in Brief | 2017

The data of establishing a three-dimensional culture system for in vitro recapitulation and mechanism exploration of tumor satellite formation during cancer cell transition

Chun-Nan Chen; You-Tzung Chen; Tsung-Lin Yang

Tumor satellite formation is an indicator of cancer invasiveness and correlates with recurrence, metastasis, and poorer prognosis. By analyzing pathological specimens, tumor satellites formed at the tumor-host interface reflect the phenomena of epithelial-mesenchymal transition. It is impossible to reveal the dynamic processes and the decisive factors of tumor satellite formation using clinicopathological approaches alone. Therefore, establishment of an in vitro system to monitor the phenomena is important to explicitly elucidate underlying mechanisms. In this study, we explored the feasibility of creating an in vitro three-dimensional collagen culture system to recapitulate the process of tumor satellite formation. This data presented here are referred to the research article (Chen et al., 2017) [1]. Using this model, the dynamic process of tumor satellite formation could be recapitulated in different types of human cancer cells. Induced by calcium deprivation, the treated cells increased the incidence and migratory distance of tumor satellites. E-cadherin internalization and invadopodia formation were enhanced by calcium deprivation and were associated with cellular dynamic change during tumor satellite formation. The data confirmed the utility of this culture system to recapitulate dynamic cellular alteration and to explore the potential mechanisms of tumor satellite formation.


Medicine | 2016

Application of Ultrasound-Guided Core Biopsy to Minimal-Invasively Diagnose Supraclavicular Fossa Tumors and Minimize the Requirement of Invasive Diagnostic Surgery.

Chun-Nan Chen; Che-Yi Lin; Fan-Hsiang Chi; Chen-Han Chou; Ya-Ching Hsu; Yen-Lin Kuo; Chih-Feng Lin; Tseng-Cheng Chen; Cheng-Ping Wang; Pei-Jen Lou; Jenq-Yuh Ko; Tzu-Yu Hsiao; Tsung-Lin Yang

AbstractTumors of the supraclavicular fossa (SC) is clinically challenging because of anatomical complexity and tumor pathological diversity. Because of varied diseases entities and treatment choices of SC tumors, making the accurate decision among numerous differential diagnoses is imperative. Sampling by open biopsy (OB) remains the standard procedure for pathological confirmation. However, complicated anatomical structures of SC always render surgical intervention difficult to perform. Ultrasound-guided core biopsy (USCB) is a minimally invasive and office-based procedure for tissue sampling widely applied in many diseases of head and neck. This study aims to evaluate the clinical efficacy and utility of using USCB as the sampling method of SC tumors. From 2009 to 2014, consecutive patients who presented clinical symptoms and signs of supraclavicular tumors and were scheduled to receive sampling procedures for diagnostic confirmation were recruited. The patients received USCB or OB respectively in the initial tissue sampling. The accurate diagnostic rate based on pathological results was 90.2% for USCB, and 93.6% for OB. No significant difference was noted between USCB and OB groups in terms of diagnostic accuracy and the percentage of inadequate specimens. All cases in the USCB group had the sampling procedure completed within 10 minutes, but not in the OB group. No scars larger than 1 cm were found in USCB. Only patients in the OB groups had the need to receive general anesthesia and hospitalization and had scars postoperatively. Accordingly, USCB can serve as the first-line sampling tool for SC tumors with high diagnostic accuracy, minimal invasiveness, and low medical cost.


Scientific Reports | 2017

The application of ultrasound in detecting lymph nodal recurrence in the treated neck of head and neck cancer patients

Chi-Maw Lin; Cheng-Ping Wang; Chun-Nan Chen; Che-Yi Lin; Ting-Yi Li; Chen-Han Chou; Ya-Ching Hsu; Po-Yen Kuo; Tsung-Lin Yang; Pei-Jen Lou; Jenq-Yuh Ko; Tseng-Cheng Chen

Early detection of neck lymph node (LN) recurrence is paramount in improving the prognosis of treated head and neck cancer patients. Ultrasound (US) with US-guided fine needle aspiration (FNA) and core needle biopsy (CNB) have been shown to have great accuracy for LN diagnoses in the untreated neck. However, in the treated neck with fibrosis, their roles are not clarified. Here, we retrospectively review 153 treated head and neck cancer patients who had received US and US-guided FNA/CNB. In multivariate logistic regression analyses, size (short-axis diameter >0.8 cm) (odds ratio (OR) 4.19, P = 0.007), round shape (short/long axis ratio >0.5) (OR 3.44, P = 0.03), heterogeneous internal echo (OR 3.92, P = 0.009) and irregular margin (OR 7.32, P < 0.001) are effective US features in predicting recurrent LNs in the treated neck. However, hypoechogenicity (OR 2.38, P = 0.289) and chaotic/absent vascular pattern (OR 3.04, P = 0.33) are ineffective. US-guided FNA (sensitivity/specificity: 95.24%/97.92%) is effective in the treated neck, though with high non-diagnostic rate (29.69%). US-guided CNB (sensitivity/specificity: 84.62%/100%) is also effective, though with low negative predictive value (62.5%). Overall, US with US-guided FNA/CNB are still effective diagnostic tools for neck nodal recurrence surveillance.


Biomaterials | 2018

Application of three-dimensional collagen scaffolds to recapitulate and monitor the dynamics of epithelial-mesenchymal transition during tumor satellite formation of head and neck cancer

Chun-Nan Chen; You-Tzung Chen; Tsung-Lin Yang

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Tsung-Lin Yang

National Taiwan University

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Cheng-Ping Wang

National Taiwan University

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Pei-Jen Lou

National Taiwan University

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Tseng-Cheng Chen

National Taiwan University

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Jenq-Yuh Ko

National Taiwan University

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Tzu-Yu Hsiao

National Taiwan University

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Che-Yi Lin

National Taiwan University

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Chen-Han Chou

National Taiwan University

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Ya-Ching Hsu

National Taiwan University

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You-Tzung Chen

National Taiwan University

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