Association of Soda Drinks and Fast Food with Allergic Diseases in Korean Adolescents: A Nationwide Representative Study.

INTRODUCTION: A high consumption of carbonated soft drinks (i.e., soda drinks) and fast food is potentially associated with the observed global rise in adolescent allergic diseases. Thus, our study aimed to examine the potential associations between the consumption of soda drinks and fast food and allergic conditions, identifying specific relationships across subgroups and each allergic condition (asthma, allergic rhinitis, and atopic dermatitis). METHODS: This study uses large-scale data from the Korea Youth Risk Behavior Web-Based Survey (total n = 865,614). Soda drinks and fast food were defined by a self-reported questionnaire and allergic conditions by physician-diagnosed within 1 year. Multivariable logistic regression was used to analyze the weighted odds ratios (ORs), along with 95% confidence intervals (CIs), for allergic diseases associated with the intake of soda drinks and fast food. RESULTS: Among 865,614 adolescents in grades 7-12 (male, 51.40%), patients with asthma, allergic rhinitis, and atopic dermatitis were 18,568 (2.15%), 153,536 (17.74%), and 59,014 (6.82%), respectively. Current asthma was associated with soda drinks (OR, 1.07; 95% CI, 1.03-1.12) and fast food consumption (1.25; 1.17-1.33). Interestingly, stronger associations were observed for female high schoolers, compared to male high schoolers and middle schoolers, in relation to the consumption of soda drinks (1.31; 1.19-1.44) and fast food (1.46; 1.26-1.69) with asthma. Current allergic rhinitis and atopic dermatitis had no significant association with fast food consumption and soda drinks. CONCLUSION: This first large-scale study suggests that fast food and soda drinks consumption are potentially associated with current asthma, with stronger associations observed in females than males, underscoring the need for sex-specific allergy prevention programs.

Factors predicting different times for brushing teeth during the day: multilevel analyses.

BACKGROUND: The most effective and simple intervention for preventing oral disease is toothbrushing. However, there is substantial variation in the timing of brushing teeth during the day. We aimed to identify a comprehensive set of predictors of toothbrushing after lunch and after dinner and estimated contextual (i.e., geographic) variation in brushing behavior at different times of the day. METHODS: We constructed a conceptual framework for toothbrushing by reviewing health behavior models. The main data source was the 2017 Community Health Survey. We performed a four-level random intercept logistic regression to predict toothbrushing behavior. (individual, household, Gi/Gun/Gu, and Si/Do). RESULTS: Individuals under 30 years of age had higher likelihood of brushing after lunch, while brushing after dinner was higher among those aged 40-79 years. People engaged in service/sales, agriculture/fishing/labor/mechanics, as well as student/housewife/unemployed were 0.60, 0.41, and 0.49 times less likely to brush their teeth after lunch, respectively, compared to those working in the office, but the gap narrowed to 0.97, 0.96, 0.94 for brushing after dinner. We also found significant area-level variations in the timing of brushing. CONCLUSIONS: Different patterns in association with various factors at individual-, household- and Si/Gun/Gu-levels with toothbrushing after lunch versus toothbrushing after dinner suggests a need for tailored interventions to improve toothbrushing behavior depending on the time of day.

Differential Clearance of Aß Species from the Brain by Brain Lymphatic Endothelial Cells in Zebrafish.

The failure of amyloid beta (Aß) clearance is a major cause of Alzheimer's disease, and the brain lymphatic systems play a crucial role in clearing toxic proteins. Recently, brain lymphatic endothelial cells (BLECs), a non-lumenized lymphatic cell in the vertebrate brain, was identified, but Aß clearance via this novel cell is not fully understood. We established an in vivo zebrafish model using fluorescently labeled Aß42 to investigate the role of BLECs in Aß clearance. We discovered the efficient clearance of monomeric Aß42 (mAß42) compared to oligomeric Aß42 (oAß42), which was illustrated by the selective uptake of mAß42 by BLECs and peripheral transport. The genetic depletion, pharmacological inhibition via the blocking of the mannose receptor, or the laser ablation of BLECs resulted in the defective clearance of mAß42. The treatment with an Aß disaggregating agent facilitated the internalization of oAß42 into BLECs and improved the peripheral transport. Our findings reveal a new role of BLECs in the differential clearance of mAß42 from the brain and provide a novel therapeutic strategy based on promoting Aß clearance.

Folate, alcohol, ADH1B and ALDH2 and colorectal cancer risk.

OBJECTIVE: There is limited evidence on the interaction by alcohol dehydrogenase 2 (ADH1B) (rs1229984) and aldehyde dehydrogenase 2 (ALDH2) (rs671) regarding the associations of alcohol and a methyl diet (low folate and high alcohol intake) with cancer risk, partly because of rare polymorphisms in Western populations. DESIGN: In a case-control study, we estimated the ORs and 95 % CIs to evaluate the associations of ADH1B and ALDH2 genotypes with colorectal cancer (CRC) and the joint association between methyl diets and ADH1B and ALDH2 polymorphisms with CRC risk using logistic regression models. SETTING: A hospital-based case-control study. PARTICIPANTS: In total, 1001 CRC cases and 899 cancer-free controls admitted to two university hospitals. RESULTS: We found that alcohol intake increased the risk of CRC; OR (95 % CI) was 2·02 (1·41, 2·87) for ≥60 g/d drinkers compared with non-drinkers (Ptrend < 0·001). The associations for two polymorphisms with CRC were not statistically significant. However, we found a potential interaction of ALDH2 with methyl diets and CRC. We observed a 9·08-fold (95 % CI 1·93, 42·60) higher risk of CRC for low-methyl diets compared with high-methyl diets among individuals with an A allele of ALDH2, but the association was not apparent among those with ALDH2 GG (Pinteraction = 0·02). CONCLUSIONS: Our data support the evidence that gene-methyl diet interactions may be involved in CRC risk in East Asian populations, showing that a low-methyl diet increased the risk of CRC among individuals with an A allele of ALDH2.

Ion-Selective Carbon Nanotube Field-Effect Transistors for Monitoring Drug Effects on Nicotinic Acetylcholine Receptor Activation in Live Cells.

We developed ion-selective field-effect transistor (FET) sensors with floating electrodes for the monitoring of the potassium ion release by the stimulation of nicotinic acetylcholine receptors (nAChRs) on PC12 cells. Here, ion-selective valinomycin-polyvinyl chloride (PVC) membranes were coated on the floating electrode-based carbon nanotube (CNT) FETs to build the sensors. The sensors could selectively measure potassium ions with a minimum detection limit of 1 nM. We utilized the sensor for the real-time monitoring of the potassium ion released from a live cell stimulated by nicotine. Notably, this method also allowed us to quantitatively monitor the cell responses by agonists and antagonists of nAChRs. These results suggest that our ion-selective CNT-FET sensor has potential uses in biological and medical researches such as the monitoring of ion-channel activity and the screening of drugs.

Rifabutin and Furazolidone Could Be the Candidates of the Rescue Regimen for Antibiotic-Resistant H. pylori in Korea.

Background/Aim. In Korea, the rate of Helicobacter pylori (H. pylori) eradication has declined steadily as a result of increasing resistance to antibiotics, especially dual resistance to clarithromycin and metronidazole. However, microbiological culture data on drug-resistant H. pylori is lacking. This study evaluated the antimicrobial efficacy of candidate antibiotics against resistant H. pylori strains. Methods. After retrospectively reviewing the data from the Helicobacter Registry in Gil Medical Center (GMC) and Asan Medical Center (AMC), along with 4 reference strains, we selected the 31 single- or multidrug-resistant strains. The susceptibility of the H. pylori strains to seven antibiotics (clarithromycin, metronidazole, levofloxacin, amoxicillin, tetracycline, rifabutin, and furazolidone) and minimum inhibitory concentration were tested using the broth microdilution technique. Results. Among 31 antibiotic resistance strains for H. pylori, there were no strains resistant to rifabutin or furazolidone, which had MICs of <0.008 and 0.5 µg/mL, respectively. Only one tetracycline-resistant strain was found (MIC < 2 µg/mL). Amoxicillin and levofloxacin were relatively less effective against the H. pylori strains compared to rifabutin or furazolidone (resistance rates 22.6%, 1.9%, respectively). Tetracycline showed the relatively low resistance rates (3.2%) for H. pylori strains. Conclusions. Therefore, along with tetracycline which has already been used as a component for second-line eradication regimen for Helicobacter, rifabutin and furazolidone, alone or in combination, could be used to eradicate antibiotic-resistant H. pylori strains where drug-resistant Helicobacter spp. are increasing.

Conversion of retardation dispersion in self-organized smectic reactive mesogen compound and its dependence on the UV polymerization temperature and the molecular orientation.

We investigated the dependence of the dispersion of retardation on the UV-polymerization temperature and the molecular orientation in a self-organized smectic host-guest reactive mesogen (RM) compound. The positive dispersion of retardation was converted to the negative dispersion of retardation with decreasing the UV-polymerization temperature. From the Fourier-transform infrared (FT-IR) dichroism measurement, it was found that more fractions of the guest molecules were aligned parallel to the smectic layer plane with decreasing the UV-polymerization temperature. The guest molecules located in the inter-layer space absorb a longer wavelength of UV light compared to the host and induce the negative dispersion of retardation.

The age-related characteristics of adults with asthma who visited emergency departments in Korea from 2007 to 2012.

BACKGROUND: Understanding the patterns of emergency department (ED) visits of patients with asthma is important for disease control and prevention of exacerbations. OBJECTIVE: This study aimed to investigate the characteristics of adult patients who visited EDs because of their asthma. METHODS: Patients with asthma, ages ≥19 years old, who visited 117 EDs throughout Korea between January 2007 and December 2012 were identified in the National Emergency Department Information System (NEDIS) data base using the International Classification of Disease, 10th revision, codes J45 (asthma) and J46 (status asthmaticus). RESULTS: A total of 97,835 adult patients with asthma visited 117 EDs throughout Korea during the study period. There was a slight female preponderance (male-to-female ratio, 1:1.09). The number of patients aged 70-79-years-old was 28,031 (28.7%), the highest among the patients with asthma. ED visits showed a seasonal distribution, with most occurring in winter and spring, followed by autumn. The seasonal distribution varied by age; most patients ages 19-49 years presented in autumn (September), whereas those patients ages ≥50 years presented to the ED most often in winter. Overall, 65.5% of patients were admitted to the hospital, including 12.6% admitted to an intensive care unit (ICU). Overall, 209 patients (0.2%) died. The rates of hospital admission to general wards and ICUs were highest in those patients ≥70 years old; this group also had the highest mortality rate. CONCLUSION: In this nationwide study, which spanned 6 years, of adult patients with asthma, we observed an age-specific seasonal pattern of ED visits. Identifying the causes of age-related deterioration and seasonal visits to the ED will help prevent asthma symptoms and reduce medical costs.

An Antibody-Immobilized Silica Inverse Opal Nanostructure for Label-Free Optical Biosensors.

Three-dimensional SiO2-based inverse opal (SiO2-IO) nanostructures were prepared for use as biosensors. SiO2-IO was fabricated by vertical deposition and calcination processes. Antibodies were immobilized on the surface of SiO2-IO using 3-aminopropyl trimethoxysilane (APTMS), a succinimidyl-[(N-maleimidopropionamido)-tetraethyleneglycol] ester (NHS-PEG4-maleimide) cross-linker, and protein G. The highly accessible surface and porous structure of SiO2-IO were beneficial for capturing influenza viruses on the antibody-immobilized surfaces. Moreover, as the binding leads to the redshift of the reflectance peak, the influenza virus could be detected by simply monitoring the change in the reflectance spectrum without labeling. SiO2-IO showed high sensitivity in the range of 10³-105 plaque forming unit (PFU) and high specificity to the influenza A (H1N1) virus. Due to its structural and optical properties, SiO2-IO is a promising material for the detection of the influenza virus. Our study provides a generalized sensing platform for biohazards as various sensing strategies can be employed through the surface functionalization of three-dimensional nanostructures.

On-Site Detection of Aflatoxin B1 in Grains by a Palm-Sized Surface Plasmon Resonance Sensor.

Aflatoxins (AFs) are highly toxic compounds that can cause both acute and chronic toxicity in humans. Aflatoxin B1 (AFB1) is considered the most toxic of AFs. Therefore, the rapid and on-site detection of AFB1 is critical for food safety management. Here, we report the on-site detection of AFB1 in grains by a portable surface plasmon resonance (SPR) sensor. For the detection of AFB1, the surface of an SPR Au chip was sequentially modified by cysteine-protein G, AFB1 antibody, and bovine serum albumin (BSA). Then, the sample solution and AFB1-BSA conjugate were flowed onto the Au chip in serial order. In the absence of AFB1, the SPR response greatly increased due to the binding of AFB1-BSA on the Au chip. In the presence of AFB1, the SPR response showed little change because the small AFB1 molecule binds on the Au chip instead of the large AFB1-BSA molecule. By using this portable SPR-based competitive immunoassay, the sensor showed low limits of detection (2.51 ppb) and quantification (16.32 ppb). Furthermore, we successfully detected AFB1 in rice, peanut, and almond samples, which suggests that the proposed sensing method can potentially be applied to the on-site monitoring of mycotoxins in food.

Identification of Susceptibility Loci and Genes for Colorectal Cancer Risk.

BACKGROUND & AIMS: Known genetic factors explain only a small fraction of genetic variation in colorectal cancer (CRC). We conducted a genome-wide association study to identify risk loci for CRC. METHODS: This discovery stage included 8027 cases and 22,577 controls of East-Asian ancestry. Promising variants were evaluated in studies including as many as 11,044 cases and 12,047 controls. Tumor-adjacent normal tissues from 188 patients were analyzed to evaluate correlations of risk variants with expression levels of nearby genes. Potential functionality of risk variants were evaluated using public genomic and epigenomic databases. RESULTS: We identified 4 loci associated with CRC risk; P values for the most significant variant in each locus ranged from 3.92 × 10(-8) to 1.24 × 10(-12): 6p21.1 (rs4711689), 8q23.3 (rs2450115, rs6469656), 10q24.3 (rs4919687), and 12p13.3 (rs11064437). We also identified 2 risk variants at loci previously associated with CRC: 10q25.2 (rs10506868) and 20q13.3 (rs6061231). These risk variants, conferring an approximate 10%-18% increase in risk per allele, are located either inside or near protein-coding genes that include transcription factor EB (lysosome biogenesis and autophagy), eukaryotic translation initiation factor 3, subunit H (initiation of translation), cytochrome P450, family 17, subfamily A, polypeptide 1 (steroidogenesis), splA/ryanodine receptor domain and SOCS box containing 2 (proteasome degradation), and ribosomal protein S2 (ribosome biogenesis). Gene expression analyses showed a significant association (P < .05) for rs4711689 with transcription factor EB, rs6469656 with eukaryotic translation initiation factor 3, subunit H, rs11064437 with splA/ryanodine receptor domain and SOCS box containing 2, and rs6061231 with ribosomal protein S2. CONCLUSIONS: We identified susceptibility loci and genes associated with CRC risk, linking CRC predisposition to steroid hormone, protein synthesis and degradation, and autophagy pathways and providing added insight into the mechanism of CRC pathogenesis.

Simple and rapid detection of bacteria using a nuclease-responsive DNA probe.

We demonstrate simple and rapid bacterial detection using a nuclease-responsive DNA probe. The probe consisting of a fluorescent dye and a quencher at the 5' and 3' termini, respectively, was designed to be cleaved by nucleases such as endonucleases, exonucleases, and DNases, which are released from bacteria using an optimized lysis buffer. The fluorescence signal of the cleaved DNA probe correlates with the number of Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus, and the detection limit was 103 CFU for E. coli and 104 CFU for S. aureus. Moreover, this method is specific for live bacteria and takes just one minute to get the signal including sample collection. These features make the present bacterial detection method a powerful on-site bacterial contamination assay which is simple, rapid, and quantitative.

Relationships between cognitive function and body composition among community-dwelling older adults: a cross-sectional study.

BACKGROUND: Previous studies reported mixed results regarding the association between cognition and body weight in late life. We evaluated the relationships between cognitive function and body composition among community-dwelling older adults. METHODS: Three hundred twenty subjects (≥65 years, women 53%) with available data of cognitive function and body composition from 2010 Hallym Aging Study. Cognitive function was assessed using Korean Mini-Mental State Examination (K-MMSE). Dual-energy X-ray absorptiometry (DEXA) was used for measuring body composition including body fat and lean body mass. Anthropometric measurements and laboratory data were collected in clinical examination. Body composition variables were divided into sex-specific tertiles, and examined by multivariable logistic regression. RESULTS: Among female, the highest tertile group of fat mass and second tertile group of total lean body mass were associated with lower risk for cognitive impairment compared to the respective first tertile groups (odds ratios, 0.23 and 0.09, respectively; 95% confidence intervals, 0.04-0.88 and 0.01-0.44, respectively) after adjusting for confounding factors. In male, higher arm bone mineral content was associated with lower risk for cognitive impairment, but significance was lost after adjusting for adiponectin, age, and education. CONCLUSIONS: Higher fat mass and lean body mass were associated with lower risk of cognitive impairment in older women. These observations suggest that body fat and lean mass later in life might be beneficial for cognition.

Treatment of comminuted proximal humeral fractures using locking plate with strut allograft.

BACKGROUND: This study compared the radiologic outcome of fixation using locking plate only with fixation using locking plate with an endosteal strut allograft in the treatment of comminuted proximal humeral fracture. METHODS: Among 52 patients with comminuted proximal humeral fracture, 32 patients underwent fixation with locking plate only, and 20 patients underwent fixation using locking plate with an endosteal strut allograft. The strut allograft was inserted into the intramedullary cavity of the humerus to support the humeral head and fixed with the locking plate. Immediate postoperative radiologic findings were compared with those of 6 months or more after the surgery, and loss of anatomic fixation was defined if the varus malalignment of neck-shaft angle (NSA) was more than 5° or if the change of humeral head height (HHH) was more than 3 mm. RESULTS: In the locking plate-only group, 22 of 32 patients (69%) showed the change in NSA of more than 5°, with an average of 10.2°. The HHH change in 20 patients (62.5%) was more than 3 mm, with an average of 4 mm. Among 20 patients who underwent locking plate with the endosteal strut allograft, the average NSA and HHH change was 3° and 1 mm, respectively. Varus malalignment was evident in 2 patients (10%). The HHH change was more than 3 mm in 1 patient (5%). CONCLUSION: Fixation using a locking plate with an endosteal strut allograft can be considered a reasonable option to maintain the anatomic reduction in elderly patients with comminuted proximal humeral fracture.

Prevalence of asymptomatic rotator cuff tear and their related factors in the Korean population.

BACKGROUND: No information is available about asymptomatic rotator cuff tears (RCTs) in the Korean population. This study evaluated the prevalence of rotator cuff tears without symptoms and their related risk factors. MATERIALS AND METHODS: The study included 486 volunteers (70.4% female; mean age, 53.1; range, 20-82 years) without any shoulder symptom complaints. Background data, medical history, clinical self-assessment, and physical examination were recorded. An ultrasonographic examination was conducted to identify rotator cuff pathology, but only full-thickness RCTs (FTRCTs) were included for the statistical analysis. RESULTS: FTRCTs were found in 23 subjects (4.7%) but only in those aged ≥49 years. Subjects aged 50-59, 60-69, and ≥70 years of age had FTRCT prevalence rates of 3.5%, 13.3%, and 11.1%, respectively. The prevalence of FTRCTs was higher in subjects with diabetes (P = .042) and a smoking history (P= .002), but no differences were noted for the presence of thyroid disease (P = .051). Almost half of those who had FTRCTs had some pain and limited daily activity that was not bothersome. After excluding these subjects from the analysis, the prevalence of asymptomatic FTRCTs decreased to 2.3%. CONCLUSIONS: The prevalence of asymptomatic FTRCTs was lower than expected. Half of asymptomatic FTRCTs were not actually symptom free after the clinical and physical assessments. The risk factors for a FTRCT were age, diabetes, and smoking.

Evaluation of the effects of the combination of autologous mesenchymal stem cells and platelet-rich plasma on structural bone allograft healing.

In this study, we evaluated the efficacy of the combination of autologous mesenchymal stem cells (MSCs) and platelet-rich plasma (PRP) for enhancing structural allogenic bone graft healing in rabbits. For these experiments segmental bone defects (1.5-2 cm) were generated on femoral diaphysis of New Zealand white rabbits and reconstructed via structural allogenic bone grafting and additional intramedullary nail fixation. The structural allografts were subsequently wrapped with Gelfoam containing autologous MSCs and PRP, or PRP alone (control). Grafted periosteal tissues were harvested at 4, 8, and 12 weeks post-implantation and subjected to plain radiographic and, histological, as well as real-time quantitative reverse transcription-PCR analysis of bone morphogenic protein (BMP)-2, BMP-4, BMP-7, receptor activator of nuclear factor-kappa B ligand (RANKL), and vascular endothelial growth factor (VEGF) expression. Compared to those in the control group, the animals in the experimental group exhibited significantly higher Taira radiographic scores at 4 and 12 weeks after surgery, as well as callus formation. Likewise, these animals exhibited increases in BMP-4 production at 4 weeks, RANKL production at 4 and 12 weeks, and BMP-2, BMP-7, and VEGF production at 4, 8, and 12 weeks. Together, these data suggest that the administration of autologous MSCs and PRP resulted in enhanced healing of structural allogenic bone grafts compared to PRP alone. As such, this combination might comprise an ideal therapy for improving the clinical outcomes of structural allografts.

Early weaning of calves after different dietary regimens affects later rumen development, growth, and carcass traits in Hanwoo cattle.

OBJECTIVE: The main objective of this study was to determine the effect of different diets for early-weaned (EW) calves on rumen development, and how this affects fat deposition in the longissimus dorsi of adult Korean Hanwoo beef cattle. METHODS: Three EW groups were established (each n = 12) in which two- week-old Hanwoo calves were fed for ten weeks with milk replacer+concentrate (T1), milk replacer+concentrate+ roughage (T2), or milk replacer+concentrate+30% starch (T3); a control group (n = 12) was weaned as normal. At six months, 5 calves of each group were slaughtered and their organs were assessed and rumen papillae growth rates were measured. The remaining calves (n = 7 in each group) were raised to 20 months for further analysis. RESULTS: Twenty-month-old EW calves had a higher body weight (BW), backfat thickness (BF), longissimus dorsi muscle area (LMA) and intramuscular fat (IMF) than the control (p<0.05). Organ growth, rumen histology, and gene expression patterns in the 6-month-old calves were positively related to the development of marbling in the loin, as assessed by ultrasound analysis (p<0.05). In the group fed the starch-enriched diet (T3), higher BW, BF, LMA, and IMF were present. The IMF beef quality score of 20-month-old cattle was 1+ for the T2 and T3 diets and 1 for the T1 diet (p<0.05). CONCLUSION: Papillae development was significantly greater in calves fed on high-concentrate diets and this may have resulted in the improved beef quality in the EW dietary groups compared to the control.

Korean Version of the painDETECT Questionnaire: A Study for Cultural Adaptation and Validation.

OBJECTIVE: The purpose of this study was to adapt the painDETECT Questionnaire (PD-Q) into a Korean version (KPD-Q) and validate it. METHODS: A single-center prospective observational study was performed. During the first phase of the study, linguistic adaptation was carried out to develop the KPD-Q. During the second phase of the study, feasibility, internal consistency, discriminant validity, and concurrent validity were assessed for psychometric validation of the KPD-Q. RESULTS: A total of 232 patients participated. Among them, 82 patients (35%) were classified in the neuropathic pain (NeP) group, 80 (34%) in the nociceptive pain group, and 70 (30%) in the mixed pain group. Regarding the reliability of the KPD-Q, internal consistency for the whole scale was 0.804, as evaluated by Cronbach's alpha. Pearson's correlation between the Leeds Assessment of Neuropathic Symptoms and Signs scale and the KPD-Q scores was positive and statistically significant (r = 0.74, P < 0.001). Similar to the result obtained by the original developers, a value of ≥ 19 points suggested a clear diagnosis of the presence of an NeP component with 95.4% sensitivity, 73.8% specificity, and 0.737 Youden index. We used ≤ 13 (as opposed to ≤ 12, as suggested previously) as an alternative cutoff value, which showed a sensitivity of 95.4%, specificity of 73.8%, and the Youden index of 0.691. CONCLUSION: The KPD-Q showed good psychometric and discriminant features for assessing the neuropathic component in chronic pain patients. We hope that this newly validated KPD-Q will be recognized in Korea as a credible tool for detection of NeP and thus may be used in further international clinical research.

Simultaneous retardation compensation during bending of plastic film coated with a polymer layer of opposite birefringence.

We proposed a method of eliminating the bending-induced retardation of a plastic film by coating it with a polymer layer with an opposite birefringence. We coated a polystyrene (PS) or a poly(methyl methacrylate) (PMMA) layer on a polycarbonate (PC) plastic film. The bare PC film is composed of main-chain-type polymers and showed an increase in retardation with bending. The main-chains of the PC polymer are reoriented along the circular arc direction during bending, resulting in a positive birefringence. In contrast, the 11 wt. % PS-coated and the 19 wt. % PMMA-coated PC films showed minimal change in the retardation regardless of the radius of curvature. The PS and the PMMA polymers are of the side-chain-type, and the side-chains were aligned perpendicular to the circular arc direction during bending, resulting in a negative birefringence. Consequently, the bending-induced retardation of the PC film can be compensated by the PS or the PMMA layer during bending of the film. This method of compensating for the bending-induced retardation of the plastic film can be useful for flexible display applications.

Surgical treatment of lesions of the long head of the biceps brachii tendon with rotator cuff tear: a prospective randomized clinical trial comparing the clinical results of tenotomy and tenodesis.

BACKGROUND: Tenotomy and tenodesis are common treatments for lesions in the long head of biceps tendon (LHBT); however, which treatment is superior is still controversial. This study compared the outcomes of tenotomy with outcomes of tenodesis for treatment of LHBT lesions with rotator cuff tears. METHODS: The study enrolled 128 patients with LHBT lesions and small- to medium-sized rotator cuff tear. Arthroscopic LHBT tenotomy was done in 56 patients (group I), and LHBT tenodesis was done for 72 patients (group II) with rotator cuff repair. American Shoulder and Elbow Surgeons Score, simple shoulder test, pain visual analog scale, range of motion, and cosmetic changes were assessed initially, at 3, 6, and 12 months postoperatively, and the last visit. The elbow motor power and magnetic resonance imaging were evaluated at 12 months. RESULTS: Both groups showed improvement in functional scores after treatments, but no significant difference was found between the 2 groups at each assessment. The rate of Popeye deformity was 3 times higher in group I (P = .04). Group II showed greater forearm supination power than group I (P = .02). On magnetic resonance imaging, 45 patients (80.4%) in group I showed maintenance of the LHBT cut end within the bicipital groove, whereas 65 patients (90.3%) in group II showed maintenance of fixated LHBT. CONCLUSION: For the treatment of LHBT lesions with rotator cuff tear, patients with tenotomy and tenodesis both showed significant improvements in functional scores. The incidence of Popeye deformity was about 3-times higher in tenotomy group. No significant differences in elbow motor power were observed except greater forearm supination power in the tenodesis group.