Direct Solution-Phase Synthesis and Functionalization of 2D WSe2 for Ambient Stability.

2H phase tungsten diselenide (WSe2 ) is a p-type 2D semiconductor from the transition metal dichalcogenides (TMDs) family with unique optoelectrical properties. Solution phase production of atomically thin WSe2 is challenging due to its instability under ambient conditions. We present a highly efficient and scalable solution method for simultaneously exfoliating and functionalizing WSe2 by leveraging the non-covalent interaction between mercapto-group and bulk WSe2 . Single and few-layer 2H phase pure WSe2 sheets of lateral size up to 5 µm with minimal basal plane defects, as revealed by XPS, Raman and FTIR spectroscopy, are produced in a water-ethanol mixture. Remarkably, WSe2 dispersion remains stable even at high concentrations (10 mg/mL) and exhibited high colloidal stability with a shelf-life exceeding a year. The findings from our study suggest that through precise manipulation of intercalation chemistry, mass production of solution-processable phase-sensitive 2D materials such as WSe2 can be achieved. This advancement holds great potential for facilitating their practical utilization in various real-world applications.

The assessment of reliability of cognitive evoked potential in normal person.

OBJECTIVE: To evaluate intra-tester reliability of P300 more precisely, this study was designed. Event-related potential (ERP) is the result of endogenous brain response following cognitive stimulus. The P300 component of the human ERP is a positive wave with a latency of 300 ms or greater. Our purpose of this study was to estimate reliability of P300 latency and amplitude with 30 normal persons without head injury, as well as to set up them as the reference values in the event that they would be found to be highly reliable. METHODS: ERP was performed at three separate times on 30 normal adults in their 20s and 30s. We measured P300 latency and amplitude among ERP. RESULTS: P300 latency show excellent reliability with intraclass correlation coefficient (ICC) of 0.81. As to P300 amplitude, reliability was good to fair with ICC of 0.53. Average value of P300 latency was 311.3±37.0 ms, shorter than reference value of previous study in Korea. CONCLUSION: P300 latency revealed higher reliability than P300 amplitude, although reliability of P300 was confirmed in both component. After further study including precise mechanism, influence factor on measurement and method standardization, it is expected to be an objective indicator to assess the cognitive state and predict prognosis.

Expression of matrix metalloproteinase-12 is correlated with extracapsular spread of tumor from nodes with metastasis in head and neck squamous cell carcinoma.

Matrix metalloproteinases (MMPs) play an important role in tumor invasiveness and metastasis. The aim of this study was to investigate the expression pattern of MMPs in the primary tumor of head and neck squamous cell carcinomas (HNSCC) with cervical node metastasis and to correlate the expression of MMP in the primary tumor with the presence of extracapsular spread (ECS) in nodes with metastasis. A retrospective study was conducted. Paraffin blocks were obtained from 40 HNSCC patients with cervical node metastasis who underwent surgery as an initial treatment between 2004 and 2011. Expressions of MMP-2, MMP-3, MMP-12, and MMP-14 were investigated immunohistochemically. MMP-2, MMP-3, MMP-12, and MMP-14 were expressed in 27, 47.5, 55, and 57.5 % of cases, respectively. MMP-12 expression was found to be significantly associated with ECS and correlated with nodal metastasis (p = 0.024, 0.011). No relation was found between MMP expression and survival. MMP-12 expressed in the primary tumor is a molecular marker that may be useful for predicting ECS in HNSCC patients with metastatic nodal disease.

Reconstruction of the head and neck region using lower trapezius musculocutaneous flaps.

BACKGROUND: Recent literature has indicated that free flaps are currently considered the preferred choice for head and neck reconstruction. However, head and neck cancer patients are frequently treated with chemoradiotherapy, which is often associated with a poor general and local condition, and thus, such patients are ineligible for free flap reconstruction. Therefore, other reconstruction modalities should be considered. METHODS: We used lower trapezius musculocutaneous (LTMC) flap based on the dorsal scapular artery to reconstruct head and neck defects that arose from head and neck cancer in 8 patients. All of the patients had undergone preoperative chemoradiotherapy. RESULTS: There were no complications except one case of partial flap necrosis; it was treated with secondary intention. Healing in the remaining patients was uneventful without hematoma, seroma, or infection. The donor sites were closed primarily. CONCLUSIONS: The LTMC flap is the preferred flap for a simple, reliable, large flap with a wide arc of rotation and minor donor-site morbidity. The authors recommend this versatile island flap as an alternative to microvascular free tissue transfer for the reconstruction of defects in the head and neck region, for patients that have undergone preoperative chemoradiotherapy.

Complete laryngotracheal separation following attempted hanging.

Laryngotracheal separation (LTS) is the most immediately life-threatening airway injury. LTS is so rare that very few otolaryngologists have experience with it. LTS is one of the diagnostic and therapeutic challenges in airway diseases and its management remains to be established. We experienced a patient with complete LTS after attempted hanging. A high index of suspicion, adequate imaging, prompt airway establishment and early surgical repair are the most vital factors in managing a patient with LTS.

Prediction of occult central lymph node metastasis in papillary thyroid carcinoma by preoperative BRAF analysis using fine-needle aspiration biopsy: a prospective study.

CONTEXT: Few reports have determined whether preoperative detection of the BRAF V600E mutation in fine-needle aspiration biopsy (FNAB) may influence determination of surgical extent such as prophylactic central lymph node dissection (CLND) in patients with papillary thyroid carcinoma (PTC). OBJECTIVES: Our objectives were to investigate whether preoperative BRAF analysis may assist determination of surgical extent, including prophylactic CLND with variable clinicopathological risk factors for central lymph node metastasis, in patients with PTC and clinically node-negative neck. PATIENTS AND METHODS: From July 2009 to May 2011, we prospectively enrolled 148 PTC patients with clinically node-negative neck who received a total thyroidectomy and prophylactic CLND. BRAF mutation by pyrosequencing was tested on preoperative FNAB specimens. The relationships between occult central lymph node metastasis and preoperative BRAF mutation or clinicopathological factors were analyzed. Additionally, we assessed the associations between preoperative BRAF mutation status and various clinicopathological characteristics of PTC revealed postoperatively. RESULTS: The prevalence of the BRAF V600E mutation was 53.4%, and the rate of occult central lymph node metastasis was 25.7%. Multivariate analysis showed that tumor size over 1 cm [P = 0.006; odds ratio (OR) = 3.559], perithyroidal invasion (P = 0.023; OR = 2.893), and preoperative positive BRAF mutation (P = 0.029; OR = 2.727) were independent risk factors for the presence of occult central lymph node metastasis. BRAF mutation examined in FNAB specimens, compared with the wild-type allele, strongly predicted perithyroidal invasion (48 vs. 29%; P = 0.017), extracapsular spread (65 vs. 45%; P = 0.017), occult central lymph node metastasis (35 vs. 15%; P = 0.004), and advanced TNM stage (44 vs. 28%; P = 0.035). In the multivariate analysis, patients with preoperative positive BRAF mutation were significantly more likely (P = 0.023; OR = 2.848) to have occult central lymph node metastasis. CONCLUSION: Preoperative BRAF analysis by FNAB and primary tumor size based on ultrasonography may assist in predicting occult central lymph node metastasis in patients with PTC and clinically node-negative neck.

Pattern of expression of cyclooxygenase-2 in malignant transformation of sinonasal inverted papilloma.

OBJECTIVE: Cyclooxygenases (COXs) are enzymes that catalyze the conversion of arachidonic acid to prostaglandins. Many studies have suggested that COX-2, the inducible form of COX, is important in carcinogenesis. However, little is known about the pattern of expression of COX-2 in a multistep process of malignant transformation of sinonasal inverted papilloma (IP). In this study, we investigated COX-2 expression in IPs, IPs with dysplasia, IPs with squamous cell carcinoma (SCC), and primary SCCs of sinonasal tract. STUDY DESIGN: A retrospective study was conducted. SETTING: The setting was a tertiary care referral center. SUBJECTS AND METHODS: The expression of COX-2 was evaluated by immunohistochemistry in 56, 7, 18, and 17 cases of IPs, IPs with dysplasia, IPs with SCC, and primary SCCs, respectively. Furthermore, we investigated the possible correlation between the expression of COX-2 and clinicopathologic variables in patients with IPs with SCC and primary SCC patients. RESULTS: Positive immunoreactivity for COX-2 was observed in 3 (5.4%) of 56 IPs, 7 (38.9%) of 18 IPs with SCC, and 7 (41.2%) of 17 primary SCCs, whereas it was not observed in IPs with dysplasia. The percentage of tumors with COX-2-positive immunostaining was significantly higher in IPs with SCC and primary SCCs compared with benign IPs. There was no significant correlation between the expression of COX-2 and clinicopathologic variables, such as tumor stage, histologic differentiation, and the proportion of malignant areas in patients with IPs with SCC. CONCLUSION: Cyclooxygenase-2 may play an important role in the process of malignant transformation from IP to SCC.

Clinical and histologic features of inverted papilloma-associated malignancy.

The objectives of the study were to analyze the clinical features of inverted papillomas (IP) associated with malignancy and to evaluate the correlation of tumor stage, survival and histolologic features. We conducted a retrospective review of 18 IP associated with malignancy patients. In addition, we compared histopathologic characteristics (tumor differentiation and malignant cell proportion) with clinical outcomes. Eleven of the tumors were present on the nasal cavity and 7 on the maxillary sinus. The rates of synchronous and metachronous malignancy were 10.1 and 1.1%, respectively. The disease-free survival rate was 83.3%. The tumors were staged as T1 (5/18), T2 (2/18), T3 (8/18), and T4 (3/18). According to the percentage of the malignant cell in the entire tumor tissue, 4 patients (22%) were in grade I, 4 patients (22%) were in grade II, 3 patients (17%) were in grade III, and 7 patients (39%) were in grade IV. There was no relationship between recurrence- and/or disease-free survival and histologic findings including tumor differentiation and malignant proportion. IP-associated malignancy tends to occur synchronously and have more favorable prognosis compared to other sinonasal malignancy. Furthermore, the proportion of malignant cell to IP and tumor stage seems not to affect the clinical outcome of IP-associated malignancy.

The clinicopathologic differences in papillary thyroid carcinoma with or without co-existing chronic lymphocytic thyroiditis.

The goal of this study is to determine the clinicopathologic differences in patients with papillary thyroid carcinoma (PTC) with or without chronic lymphocytic thyroiditis (CLT). We reviewed the medical records of 195 consecutive PTC patients who underwent total thyroidectomy and bilateral central lymph node dissection from April 2008 to March 2010. The differences in clinicopathologic factors, such as age, gender, size of primary tumor, perithyroidal invasion, lymphovascular invasion, capsular invasion, and central lymph node (CLN) metastasis, were analyzed in PTC patients with or without CLT. Among 195 patients, 56 (28.7%) had co-existing CLT. Patients with CLT had the following characteristics as compared to patients without CLT: significantly younger, female predominance, smaller tumor size, and lower incidence of capsular invasion (p = 0.038, 0.006, 0.037, and 0.026, respectively). Also, patients with CLT (12.5%) had a significantly lower incidence of CLN metastases than patients without CLT (28.1%; p = 0.025) based on univariate analysis. Moreover, multivariate analysis showed that younger age (p = 0.042, odds ratio = 1.033) and female gender (p = 0.012, odds ratio = 6.865) are independent clinical factors in patients with CLT compared to patients without CLT. CLT was shown to be commonly associated with PTC. Compared to patients with PTC without CLT, patients with CLT were younger with a female predominance, which are the most important and well-known prognostic variables for thyroid cancer mortality.

Effects of music therapy on mood in stroke patients.

PURPOSE: To investigate the effects of music therapy on depressive mood and anxiety in post-stroke patients and evaluate satisfaction levels of patients and caregivers. MATERIALS AND METHODS: Eighteen post-stroke patients, within six months of onset and mini mental status examination score of over 20, participated in this study. Patients were divided into music and control groups. The experimental group participated in the music therapy program for four weeks. Psychological status was evaluated with the Beck Anxiety Inventory (BAI) and Beck Depression Inventory (BDI) before and after music therapy. Satisfaction with music therapy was evaluated by a questionnaire. RESULTS: BAI and BDI scores showed a greater decrease in the music group than the control group after music therapy, but only the decrease of BDI scores were statistically significant (p=0.048). Music therapy satisfaction in patients and caregivers was affirmative. CONCLUSION: Music therapy has a positive effect on mood in post-stroke patients and may be beneficial for mood improvement with stroke. These results are encouraging, but further studies are needed in this field.

Is there any synergic effect for coadministration of mitomycin C and halofuginone on the skin wound healing?

OBJECTIVE: This study compared the potencies of the antifibrotic agents mitomycin C (MMC) and halofuginone (HFN) and investigated whether coadministration of these agents produces synergic effects in an animal skin wound model. SUBJECTS AND METHODS: Twenty male Sprague-Dawley rats were used for this study. After a full-thickness excisional wound was made on the dorsum of each rat, each rat was treated with topical mitomycin, intraperitoneal HFN, or both. Wound surface areas were measured over time, and histologic analysis was performed after wounds healed completely. RESULTS: The groups treated with MMC alone, HFN alone, and a combination of the two all exhibited delayed wound healing compared with the untreated group. Histologically, fibrosis and matrix metalloproteinase-2 expression were significantly inhibited in the treated groups. However, there were no gross or histologic differences between the MMC-treated group, the HFN-treated group, and the combination-treatment group. CONCLUSIONS: Both MMC and HFN inhibited excessive fibrosis. However, there was no significant difference in the antifibrotic effects of MMC and HFN on surgically induced skin wounds. Moreover, combination treatment with both MMC and HFN failed to confer an additional antifibrotic effect on skin wounds when compared with treatment with MMC or HFN alone.

Neurodevelopmental disorders of children screened by the infantile health promotion system.

OBJECTIVE: To perform an in depth evaluation of children, and thus provide a systematic method of managing children, who after infantile health screening, were categorized as suspected developmental delay. METHOD: 78 children referred to the Developmental Delay Clinic of Ilsan Hospital after suspected development delay on infantile health examinations were enrolled. A team comprised of a physiatrist, pediatrician and pediatric psychiatrist examined the patients. Neurological examination, speech and cognitive evaluation were done. Hearing tests and chromosome studies were performed when needed clinically. All referred children completed K-ASQ questionnaires. Final diagnoses were categorized into specific language impairment (SLI), global developmental delay (GDD), intellectual disability (ID), cerebral palsy (CP), motor developmental delay (MD) or autism spectrum disorder (ASD). RESULTS: 72 of the 78 patients were abnormal in the final diagnosis, with a positive predictive value of 92.3%. Thirty (38.4%) of the 78 subjects were diagnosed as GDD, 28 (35.8%) as SLI, 5 (6.4%) as ASD, 9 (12.5%) as MD, and 6 (7.6%) as normal. Forty five of the 78 patients had risk factors related to development, and 18 had a positive family history for developmental delay and/or autistic disorders. The mean number of abnormal domains on the K-ASQ questionnaires were 3.6 for ASD, 2.7 for GDD, 1.8 for SLI and 0.6 for MD. Differences between these numbers were statistically significant (p<0.05). CONCLUSION: Because of the high predictive value of the K-ASQ, a detailed evaluation is necessary for children suspected of developmental delay in an infantile health promotion system.

Characteristics of primary papillary thyroid carcinoma with false-negative findings on initial (18)F-FDG PET/CT.

BACKGROUND: We often observe that uptake of tracer is not detected in the primary cancer focus in patients with histologically proven papillary thyroid carcinoma (PTC) on preoperative (18)F-fluorodeoxyglucose positron emission tomography-computed tomography ((18)F-FDG PET/CT). Therefore, we analyzed the clinical and pathologic variables affecting false-negative findings in primary tumors on preoperative (18)F-FDG PET/CT. METHODS: We retrospectively reviewed the medical records of 115 consecutive patients who underwent (18)F-FDG PET/CT for initial evaluation and were diagnosed with PTC by postoperative permanent biopsy. The clinical and pathologic characteristics that influence the (18)F-FDG PET/CT findings in these patients were analyzed with respect to the following variables: age, gender, tumor size, multifocality of the primary tumor, perithyroidal invasion, lymphovascular or capsular invasion, and central lymph node metastasis-based final pathology. RESULTS: Twenty-six (22.6%) patients had false-negative (18)F-FDG PET/CT findings. In patients with negative (18)F-FDG PET/CT findings, tumor size, and perithyroidal and lymphovascular invasion were significantly less than in patients with positive (18)F-FDG PET/CT findings. Tumors >1 cm in size were correlated with (18)F-FDG PET/CT positivity. On multivariate analysis, perithyroidal invasion (P = 0.026, odds ratio = 7.714) and lymphovascular invasion (P = 0.036, odds ratio = 3.500) were independent factors for (18)F-FDG PET/CT positivity. However, there were no significant differences between (18)F-FDG PET/CT positivity and age, gender, capsular invasion, and central lymph node metastasis based on final pathology. CONCLUSIONS: Tumor size and perithyroidal and lymphovascular invasion of papillary carcinoma can influence (18)F-FDG PET/CT findings. Absence of perithyroidal and lymphovascular invasion were independent variables for false-negative findings on initial (18)F-FDG PET/CT in patients with PTC.

Occult contralateral carcinoma in patients with unilateral papillary thyroid microcarcinoma.

BACKGROUND: The optimal resection extent for papillary thyroid microcarcinoma (PTMC) confined within a unilateral lobe remains controversial. MATERIALS AND METHODS: We reviewed the medical records of 132 consecutive patients who underwent total thyroidectomy for the treatment of clinically unilateral PTMC between March 2005 and March 2009. The frequency, pattern, and predictive factors for occult contralateral carcinoma in these patients were analyzed with respect to the following variables: age, gender, tumor size, multifocality of primary tumor, presence of perithyroidal invasion, lymphovascular invasion or capsular invasion, presence of central lymph node metastasis, and the presence of coexistent benign nodules in the contralateral lobe based on preoperative evaluation and final pathology. RESULTS: A total of 22 patients (16.7%) had occult PTMC in the contralateral lobe. In multivariate analysis, multifocality of the primary tumor (P = 0.026, odds ratio = 7.714) and the presence of coexistent benign nodule in the contralateral lobe by preoperative evaluation (P = 0.036, odds ratio = 3.500) were independent predictive factors for occult contralateral PTMC presence. However, there were no significant differences between the presence of occult contralateral carcinomas and age, gender, tumor size, perithyroidal invasion, lymphovascular invasion, capsular invasion, central lymph node metastasis, and coexistent benign nodules by final pathology. CONCLUSIONS: Based on our findings, total thyroidectomy, including the contralateral lobe, should be considered for the treatment of unilateral PTMC if it presents as a multifocal tumor in the unilateral lobe and/or if nodules are found in the contralateral lobe during preoperative evaluation.

Occult lymph node metastases in neck level V in papillary thyroid carcinoma.

BACKGROUND: The extent of lateral neck dissection for clinically evident nodal metastases in the lateral neck in a patient with papillary thyroid cancer (PTC) continues to remain controversial. METHODS: We reviewed retrospectively the medical records between March 2005 and March 2008 of 70 patients with PTC who underwent therapeutic lateral neck dissections (level II-V) to establish indications for omission of a level V lymphadenectomy. No patient in the study had a clinically positive level V lymph node. Neck dissection specimens were obtained for histologic analysis for node metastasis with respect to the individual neck levels. RESULTS: Thirty-four (49%), 52 (74%), and 48 (69%) patients had histologically positive lymph nodes in levels II, III, and IV, respectively. Occult metastases in level V were observed in 11 (16%) patients. Isolated positive level V lymph nodes were never found, while all patients with positive level V lymph nodes had simultaneous positive level IV lymph nodes. In addition, there was no instance of a pathologically positive lymph node in level V without a suspicious metastatic lymph node in level IV by preoperative ultrasonography. In multivariate analysis, simultaneous multilevel involvement (level II, III, and IV) of lymphatic metastases was associated with level V metastasis. CONCLUSION: Level V lymphadenectomy may be omitted in the treatment of PTC patients if positive nodes are not found on histologic exam (frozen section analysis) or by ultrasonography in level IV.

The preventive effect of mitomycin-C on the external auditory canal fibrosis in an experimentally induced animal model.

OBJECTIVE: The aim of this study was to investigate the preventive effect of mitomycin-C (MMC) on external auditory canal (EAC) fibrosis in an animal model. STUDY DESIGN: This is a randomized, controlled animal study. SUBJECTS AND METHODS: Sixteen guinea pigs were used for this study. After the skin of cartilaginous EAC was injured with an electrocautery, the cottonoid soaked in MMC solution with concentration of 0.4 mg/mL was topically applied for 5 minutes to the injured EAC in an MMC-treated group (n = 8). In addition, saline was applied in the control group (n = 8). At 4 weeks after injury, postsurgical changes of EAC were evaluated by histologic examination. RESULTS: External auditory canal fibrosis was induced by injury with electrocautery. The MMC-treated group showed less degree of fibrosis without differences in epithelialization and inflammatory cell infiltration. CONCLUSION: This study suggests that MMC can be helpful in preventing EAC fibrosis after injury.

Predictive factors for ipsilateral or contralateral central lymph node metastasis in unilateral papillary thyroid carcinoma.

OBJECTIVES: To investigate the incidence and the risk factors for occult ipsilateral or contralateral central neck lymph node (LN)metastasis in patients with unilateral papillary thyroid carcinoma (PTC) and a clinically negative neck. SUMMARY BACKGROUND DATA: Elective central lymph node dissection (CLND) in patients with PTC remains controversial. There have been few prospective studies assessing accurate histopathologic information and predictive factors for the presence of metastasis to the ipsilateral or contralateral central compartment of the neck in patients with PTC and clinically negative neck nodes. METHODS: We reviewed a prospective protocol of 111 unilateral PTC patients with clinically node-negative necks who have received total thyroidectomy and elective bilateral CLND from 2005 to 2007. The relationships between LN metastasis to the ipsilateral or contralateral central neck compartment and clinico-pathologic factors such as age, sex, size of primary tumor, perithyroidal invasion, lymphovascular invasion, and capsular invasion were analyzed. RESULTS: Occult central neck LN metastasis was present in 54.1% (60/111). Of these patients, bilateral central LN metastases were present in 50% (30/60), unilateral ipsilateral central LN metastasis in 43.3% (26/60), and unilateral contralateral central LN metastasis in 6.7% (4/60). In the univariate analysis, the rate of ipsilateral central LN metastasis was significantly higher in male patients, high risk MACIS score, carcinoma with a maximal diameter of greater than 1 cm, and carcinoma with lymphovascular invasion (P < 0.05). The rate of contralateral central LN metastasis was significantly higher in cases of carcinoma with a maximal diameter of greater than 1 cm, lymphovascular invasion or histologically proven metastasis to the ipsilateral central LN (P < 0.05). Multivariate analysis showed that the tumor size was an independent risk factor for the presence of ipsilateral central LN metastasis, and the presence of ipsilateral central LN metastasis was the only independent predictor for the presence of contralateral central LN metastasis. CONCLUSIONS: Unilateral PTC with a maximal diameter of greater than 1 cm is associated with a high rate of ipsilateral central neck LN metastasis. Moreover, ipsilateral central LN metastasis is a potential independent predictor of synchronous contralateral central LN metastasis. These findings suggest that contralateral as well as ipsilateral elective CLND, performed during the initial thyroid operation, may be effective in the management of patients with unilateral PTC having a maximal diameter of greater than 1 cm and ipsilateral central LN metastasis.