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Yujin Jo,1 Yong Tae Kim,2 Hoonsung Cho,2 Min-Kyung Ji,3 Jaeyeong Heo,2,3 Hyun-Pil Lim1 1Department of Prosthodontics, School of Dentistry, Chonnam National University, Gwangju, Korea; 2Department of Materials Science and Engineering, Chonnam National University, Gwangju, 61186, Korea; 3Optoelectronics Convergence Research Center, Chonnam National University, Gwangju, 61186, Republic of KoreaCorrespondence: Hyun-Pil LimDepartment of Prosthodontics, School of Dentistry, Chonnam National University, Gwangju, 61186, KoreaTel +82-10-2645-7528Fax +82-62-530-5577Email mcnihil@jnu.ac.krJaeyeong HeoDepartment of Materials Science and Engineering, Chonnam National University, Gwangju, 61186, KoreaTel +82-62-530-1716Fax +82-62-530-1699Email jheo@jnu.ac.krPurpose: The study was intended to create a uniform zirconia layer even on the surface of complex structures via atomic layer deposition (ALD). The impact of crystalline zirconia deposited by ALD on bacterial adhesion and osteoblast viability was assessed via surface treatment of dental implants.Methods: Amorphous zirconia was deposited using an atomic layer deposition reactor (Atomic Classic, CN1, Hwaseong, Korea) on titanium discs. Heating the samples at 400°C resulted in crystallization. Samples were divided into three groups: the control group, the group carrying amorphous ALD-zirconia (Z group), and the heat-treated group following zirconia ALD deposition (ZH group).The surface of each sample was analyzed, followed by the assessment of adhesion of Streptococcus mutans and Porphyromonas gingivalis, and viability and differentiation of MC3T3-E1 cells.Results: The adhesion of S. mutans and P. gingivalis was significantly reduced in the Z and ZH groups compared with the control group (P < 0.05). The viability of MC3T3-E1 cells was significantly increased in the ZH group compared with the control group (P < 0.001), while no significant differences were observed in the Z group (P > 0.05). Differentiation of MC3T3-E1 cells showed a marginally significant increase in the ZH group compared with the control group (P < 0.1), while no significant differences were found in the Z group (P > 0.1).Conclusion: Compared with the pure titanium group, the groups that were coated with zirconia via ALD showed a decreased adhesion of S. mutans during the early stages of biofilm formation and P. gingivalis adhesion inducing peri-implantitis, and an increase in MC3T3-E1 cell viability and differentiation. The findings indicate the possibility of treating the implant surface to reduce peri-implantitis and improve osseointegration.Keywords: atomic layer deposition, ALD, surface treatment, titanium, zirconia, implant

Eun Sun Kim,1 Young Tae Kim,2 Chang Hyun Kang,2 In Kyu Park,2 Won Bae,1 Sun Mi Choi,1 Jinwoo Lee,1 Young Sik Park,1 Chang-Hoon Lee,1 Sang-Min Lee,1 Jae-Joon Yim,1 Young Whan Kim,1 Sung Koo Han,1 Chul-Gyu Yoo1 1Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, 2Department of Thoracic and Cardiovascular Surgery, Seoul National University College of Medicine, Seoul, Republic of Korea Purpose: This study aimed to investigate whether the prevalence of postoperative pulmonary complications (PPCs) in patients with non-small-cell lung cancer (NSCLC) is even higher in the early stages of COPD than in such patients with normal lung function and to verify the usefulness of symptom- or quality of life (QoL)-based scores in predicting risk for PPCs.Patients and methods: Patients undergoing pulmonary resection for NSCLC between July 2012 and October 2014 were prospectively enrolled. Preoperative measurements of lung function, dyspnea, and QoL, operative characteristics, PPCs, duration of postoperative hospitalization, and in-hospital mortality were assessed.Results: Among 351 consecutive patients with NSCLC, 343 patients with forced expiratory volume in 1 second (FEV1) ≥70% of predicted value were enrolled. At least one PPC occurred in 57 (16.6%) patients. Prevalence of PPC was higher in patients with COPD (30.1%) than in those with normal spirometry (10.0%; P

Hwa-young Lee,1 Bong-Min Yang,1 Ji-min Hong,1 Tae-Jin Lee,1 Byoung-Gie Kim,2 Jae-Weon Kim,3 Young-Tae Kim,4 Yong-Man Kim,5 Sokbom Kang61Graduate School of Public Health, Seoul National University, Seoul, South Korea; 2Department of Obstetrics and Gynecology, Samsung Medical Center, Seoul, South Korea; 3Department of Obstetrics and Gynecology, Seoul National University, Seoul, South Korea; 4Department of Obstetrics and Gynecology, Yonsei University, Seoul, South Korea; 5Department of Obstetrics and Gynecology, University of Ulsan, Ulsan, South Korea; 6Department of Obstetrics and Gynecology, National Cancer Center, Kyeonggi-do, South KoreaObjective: We performed a cost–utility analysis to assess the cost-effectiveness of a chemotherapy sequence including a combination of polyethylene glycolated liposomal doxorubicin (PLD)/carboplatin versus paclitaxel/carboplatin as a second-line treatment in women with platinum-sensitive ovarian cancer.Methods: A Markov model was constructed with a 10-year time horizon. The treatment sequence consisted of first- to sixth-line chemotherapies and best supportive care (BSC) before death. Cycle length, a time interval for efficacy evaluation of chemotherapy, was 9 weeks. The model consisted of four health states: responsive, progressive, clinical remission, and death. At any given time, a patient may have remained on a current therapy or made a transition to the next therapy or death. Median time to progressions and overall survivals data were obtained through a systematic literature review and were pooled using a meta-analytical approach. If unavailable, this was elicited from an expert panel (eg, BSC). These outcomes were converted to transition probabilities using an appropriate formula. Direct costs included drug-acquisition costs for chemotherapies, premedication, adverse-event treatment and monitoring, efficacy evaluation, BSC, drug administration, and follow-up tests during remission. Indirect costs were transportation expenses. Utilities were also derived from the literature. Costs and utilities were discounted at an annual rate of 5% per cycle.Results: PLD/carboplatin combination as the second line in the sequence is more effective and costly than paclitaxel/carboplatin combination, showing an additional US$21,658 per quality-adjusted life years. This result was robust in a deterministic sensitivity analysis except when median time to progression of second-line therapies and administration cost of PLD/carboplatin per administration cycle were varied. The probability of cost-effectiveness for PLD/carboplatin combination was 49.4% at a willingness to pay $20,000.Conclusion: A PLD/carboplatin combination is an economically valuable option as second-line chemotherapy for the treatment of platinum-sensitive ovarian cancer in South Korea.Keywords: cost, utility, Markov modeling, ovarian cancer, chemotherapy

The incidence of adjacent segment problems after lumbar fusion has been found to vary, and risk factors for these problems have not been precisely verified, especially based on structural changes determined by magnetic resonance imaging. The purpose of this retrospective clinical study was to describe the incidence and clinical features of adjacent segment disease (ASD) after lumbar fusion and to determine its risk factors. We assessed the incidence of ASD in patients who underwent lumbar or lumbosacral fusions for degenerative conditions between August 1995 and March 2006 with at least a 1-year follow-up. Patients less than 35 years of age at the index spinal fusion, patients with uninstrumented fusion, and patients who had not achieved successful union were excluded. Of the 1069 patients who underwent fusions, 28 (2.62%) needed secondary operations because of ASD and were included in this study. In order to identify the risk factors, we matched a disease group and a control group. The disease group consisted of 26 of the 28 patients with ASD, excluding the 2 patients for whom we did not have initial MRI data. Each patient in the disease group was matched by age, sex, fusion level and follow-up period with a control patient. The assumed risk factors included disc and facet degeneration, instability, listhesis, rotational deformity, and disc wedging. The mean age of the 28 patients with ASD requiring surgical treatment was 58.4 years, which did not differ significantly from that of the population in which ASD did not develop (58.2 years, p = 0.894). Of the 21 patients who underwent floating fusion, only 1 developed distal ASD. Facet degeneration was a significant risk factor (p < 0.01) on logistic regression analysis. The incidence of distal ASD was much lower than that of proximal ASD. Pre-existing facet degeneration may be associated with a high risk of adjacent segment problems following lumbar fusion procedures. [ABSTRACT FROM AUTHOR]

In recent years, efforts to develop microrobots for medical applications have been expanding. One of the key design issues in such microrobots is to attain adequate frictional interaction between the robotic foot and the organ tissue. In particular, it is important to generate the necessary frictional force without damaging the tissue. In this work, a design for the robotic foot was proposed on the basis of the frictional behaviour of a tube structure. Fundamental experiments were initially performed to understand the biotribological behaviour of the tube and rod structures. The design was then modified to a multi-tube structure to achieve adequate frictional behaviour. Biotribological investigation of a multi-tube foot in contact with a small intestine specimen of a pig was conducted using a pin-on-reciprocator type biotribotester. It was found that there is an optimum number and arrangement of the tubes for generating high frictional force. Experimental results showed that a nine-tube foot had the highest initial friction coefficient of about 1.5. The major frictional mechanism was determined to be interlocking between the tubes and the surface structures of the intestine specimen. The results of this work will aid the optimum design of frictional surface for medical microrobots and other biological devices. [ABSTRACT FROM AUTHOR]

The effect of stem bark powder from paper mulberry (PMSB) on serum glucose, insulin, fructosamine, and lipid concentrations, as well as enzyme activities that serve as liver injury markers, was investigated in genetically diabetic Otsuka Long-Evans Tokushima fatty (OLETF) rats. Both nondiabetic Long-Evans Tokushima Otsuka (LETO) rats and diabetic OLETF rats (30 weeks old) were fed a semisynthetic diet with or without 50 g/kg PMSB for 8 weeks and then compared. The OLETF control rats showed a high amount of daily water intake in comparison to those in the LETO group. The concentrations of glucose, fructosamine, total lipid, triglyceride, total cholesterol, and high-density lipoprotein-cholesterol and the activities of aspartate aminotransferase and alanine aminotransferase (ALT) in serum were higher in the OLETF control rats than those in the LETO control rats. However, PMSB ingestion decreased the serum levels of glucose, fructosamine, triglyceride, and total cholesterol and the activity of ALT in the OLETF rats, but not in the LETO rats. The concentration of serum insulin was also significantly increased by PMSB consumption in the OLETF rats compared to the OLETF control rats. These results suggest that PMSB might have an antihyperglycemic effect in the OLETF rat and that the increased blood insulin level would be an important regulatory factor for improving hyperglycemia in the current animal model. [ABSTRACT FROM AUTHOR]

Background: The clinical significance of pulmonary nodular ground-glass opacities (NGGOs) in patients with extrapulmonary cancers is not known, although there is an urgent need for study on this topic. The purpose of this study, therefore, was to investigate the clinical significance of pulmonary NGGOs in these patients, and to develop a computerized scheme to distinguish malignant from benign NGGOs.Methods: Fifty-nine pathologically proven pulmonary NGGOs in 34 patients with a history of extrapulmonary cancer were studied. We reviewed the CT scan characteristics of NGGOs and the clinical features of these patients. Artificial neural networks (ANNs) were constructed and tested as a classifier distinguishing malignant from benign NGGOs. The performance of ANNs was evaluated with receiver operating characteristic analysis.Results: Twenty-eight patients (82.4%) were determined to have malignancies. Forty NGGOs (67.8%) were diagnosed as malignancies (adenocarcinomas, 24; bronchioloalveolar carcinomas, 16). Among the rest of the NGGOs, 14 were atypical adenomatous hyperplasias, 4 were focal fibrosis, and 1 was an inflammatory nodule. There were no cases of metastasis appearing as NGGOs. Between malignant and benign NGGOs, there were significant differences in lesion size; the presence of internal solid portion; the size and proportion of the internal solid portion; the lesion margin; and the presence of bubble lucency, air bronchogram, or pleural retraction (p < 0.05). Using these characteristics, ANNs showed excellent accuracy (z value, 0.973) in discriminating malignant from benign NGGOs.Conclusions: Pulmonary NGGOs in patients with extrapulmonary cancers tend to have high malignancy rates and are very often primary lung cancers. ANNs might be a useful tool in distinguishing malignant from benign NGGOs. [ABSTRACT FROM AUTHOR]