Anti-obesity effects of agar (Gelidium amansii)-derived oligosaccharides in high-fat diet-treated C57BL/6N mice due to differential regulations of lipogenesis and lipolysis.

To investigate the effects of agar oligosaccharides (AO) on lipid metabolism, changes in obesity phenotypes and related molecular factors were evaluated in C57BL/6N mice fed a high-fat diet (HFD). When HFD-induced obese mice were fed AO, they lost weight. Also, fat accumulation in abdominal and liver tissues was lower in the AO groups than in the Vehicle group. Lipid droplet sizes in tissue sections were reduced by AO, and these observations were mirrored by serum lipid contents. To evaluate the effects of AO on lipid metabolism, lipogenesis and lipolysis-related factors were analyzed. The mRNA expressions of genes involved in lipogenesis, such as adipocyte-protein 2 (aP2) and fatty acid synthase (FAS), were reduced by AO administration, and the expressions of lipolysis-associated proteins, including perilipin, hormone-sensitive lipase (HSL), and fat triglyceride lipase (ATGL), were increased. Taken together, our results suggest that AO should be considered a valuable natural agent that inhibits obesity.

Tuning the Electrical Properties of Graphene via Nitrogen Plasma-Assisted Chemical Modification.

The control in electrical properties of graphene is essentially required in order to realize graphenebased nanoelectronics. In this study, N-doped graphene was successfully obtained via nitrogen plasma treatment. Graphene was synthesized on copper foil using thermal chemical vapor deposition. After N2 plasma treatment, the G-band of the graphene was blueshifted and the intensity ratio of 2D- to G-bands decreased with increasing the plasma power. Pyrrolic-N bonding configuration induced by N2 plasma treatment was studied by X-ray photoelectron spectroscopy. Remarkably, electrical characterization including Hall measurement and I-V characteristics of the N-doped graphene exhibit semiconducting behavior as well as the n-type doping effect.

Fabrication of graphene-based flexible devices utilizing a soft lithographic patterning method.

There has been considerable interest in soft lithographic patterning processing of large scale graphene sheets due to the low cost and simplicity of the patterning process along with the exceptional electrical or physical properties of graphene. These properties include an extremely high carrier mobility and excellent mechanical strength. Recently, a study has reported that single layer graphene grown via chemical vapor deposition (CVD) was patterned and transferred to a target surface by controlling the surface energy of the polydimethylsiloxane (PDMS) stamp. However, applications are limited because of the challenge of CVD-graphene functionalization for devices such as chemical or bio-sensors. In addition, graphene-based layers patterned with a micron scale width on the surface of biocompatible silk fibroin thin films, which are not suitable for conventional CMOS processes such as the patterning or etching of substrates, have yet to be reported. Herein, we developed a soft lithographic patterning process via surface energy modification for advanced graphene-based flexible devices such as transistors or chemical sensors. Using this approach, the surface of a relief-patterned elastomeric stamp was functionalized with hydrophilic dimethylsulfoxide molecules to enhance the surface energy of the stamp and to remove the graphene-based layer from the initial substrate and transfer it to a target surface. As a proof of concept using this soft lithographic patterning technique, we demonstrated a simple and efficient chemical sensor consisting of reduced graphene oxide and a metallic nanoparticle composite. A flexible graphene-based device on a biocompatible silk fibroin substrate, which is attachable to an arbitrary target surface, was also successfully fabricated. Briefly, a soft lithographic patterning process via surface energy modification was developed for advanced graphene-based flexible devices such as transistors or chemical sensors and attachable devices on a biocompatible silk fibroin substrate. Significantly, this soft lithographic patterning technique enables us to demonstrate a simple and efficient chemical sensor based on reduced graphene oxide (rGO), a metallic nanoparticle composite, and an attachable graphene-based device on a silk fibroin thin film.

Synthesis of graphene and carbon nanotubes hybrid nanostructures and their electrical properties.

The gapless semimetallic nature of graphene-based nanoelectronics is a major hurdle for the advancement of graphene-based field-effect transistors. Here graphene-carbon nanotubes hybrid nanostructures (Gr-CNTs HNSs) were formed by synthesizing single-walled carbon nanotubes (SWCNTs) with a bandgap on monolayer graphene by thermal chemical vapor deposition. We systematically established optimum conditions for the synthesis of Gr-CNTs HNSs by adjusting catalytic layer formation. The structural features of Gr-CNTs HNSs were investigated by scanning electron icroscopy and Raman spectroscopy. The surface morphologies and chemical states of the catlytic films used to optimize Gr-CNTs HNSs synthesis were explored by atomic force microscopy and X-ray photoelectron spectroscopy. In this process, graphene played a role as a barrier to prevent Fe nanoparticles from interdiffusing into Al2O3 layer. Based on these studies, we determined the catalytic structure (Fe/Graphene/Al2O3/SiO2) optimal for growing high-density SWCNTs on monolayer graphene. Electrical transport measurements revealed that Gr-CNTs HNSs exhibited p-type semiconducting behavior with combined properties of graphene and CNTs.

Effect of nitrogen plasma on the surface of indium oxide nanowires.

The change in the atomic nitrogen concentration on a semiconducting nanowire's surface and the consequent changes in the electrical characteristics of a nanowire transistor were investigated by exposing In(2)O(3) nanowires to nitrogen (N(2)) plasma. After plasma was applied at N(2) flow rates of 20, 40, and 70 sccm with a fixed source power of 50 W, the In(2)O(3) nanowire transistor exhibited changes in the threshold voltage (V(th)), subthreshold slope (SS), and on-current (I(on)). In particular, after treatment at an N(2) flow rate of 40 sccm, V(th) shifted positively by ~2.3 V, the SS improved by ~0.24 V/dec, and I(on) increased by ~0.8 µA on average. The changes are attributed to the combination of nitrogen ions produced by the plasma with oxygen vacancies or indium interstitials on the nanowires. Optimization of the plasma treatment conditions is expected to yield desirable device characteristics by a simple, nondestructive process.

Prediction of compensated liver cirrhosis by ultrasonography and routine blood tests in patients with chronic viral hepatitis.

BACKGROUND/AIMS: Liver biopsy is a standard method for diagnosis of liver cirrhosis in patients with chronic hepatitis. Because liver biopsy is an invasive method, non-invasive methods have been used for diagnosis of compensated liver cirrhosis in patients with chronic hepatitis. The current study was designed to evaluate the usefulness of ultrasonography and routine blood tests for diagnosis of compensated liver cirrhosis in patients with chronic viral hepatitis. METHODS: Two hundred three patients with chronic viral hepatitis who underwent liver biopsy were included in this study and ultrasonography and routine blood tests were analyzed retrospectively. Ultrasonographic findings, including surface nodularity, parenchyma echogenecity, and spleen size, were evaluated. The diagnostic accuracy of ultrasonography and routine blood tests were examined. RESULTS: Discriminant analysis with forward stepwise selection of variables showed that liver surface nodularity, platelet count, and albumin level were independently associated with compensated liver cirrhosis (p<0.05). Cross-tabulation revealed that the following 4 variables had >95% specificity: platelet count <100,000 /uL; albumin level <3.5 g/dL; INR >1.3; and surface nodularity. If at least one of the four variables exists in a patient with chronic viral hepatitis, we can predict liver cirrhosis with 90% specificity and 61% sensitivity. CONCLUSIONS: These results suggest that four variables (platelet count <100,000 /uL, albumin level <3.5 g/dL, INR >1.3, and surface nodularity) can be used for identification of liver cirrhosis in patients with chronic viral hepatitis with high specificity.

Analysis of endoscopic features for histologic discrepancies between biopsy and endoscopic submucosal dissection in gastric neoplasms: 10-year results.

BACKGROUND AND AIM: The histologic discrepancies between preoperative endoscopic forceps biopsy (EFB) and endoscopic submucosal dissection (ESD) specimens sometimes confuse the endoscope operator. This study aimed to analyze the limitation of the biopsy-based diagnosis before ESD and to evaluate which factors affect the discordant pathologic results between EFB and ESD. METHODS: A total of 1427 patients, who were diagnosed with gastric adenoma by EFB, were enrolled. Cancer confirmed on EFB was excluded (n = 513). We retrospectively reviewed cases and compared histologic diagnoses in the biopsy sample with the final diagnosis in the endoscopically resected specimen. RESULTS: The diagnosis was upgraded (from low-grade dysplasia to high-grade dysplasia or adenocarcinoma, or from high-grade dysplasia to adenocarcinoma) in 328 cases (23.0%), concordant in 944 (66.1%), and downgraded (from high-grade dysplasia to low-grade dysplasia or non-neoplasia, or from low-grade dysplasia to non-neoplasia) in 155 (10.9%). Multivariate logistic regression analysis showed that surface ulceration and depressed lesions were associated with significant risk factors for upgrading. Age younger than 60 years and size <1 cm were associated with significant factors for downgrading. CONCLUSIONS: Careful endoscopic observation should consider size, ulceration, and depression to ensure accurate diagnosis when a gastric neoplasm is suspected.

Realization of large-area wrinkle-free monolayer graphene films transferred to functional substrates.

Structural inhomogeneities, such as the wrinkles and ripples within a graphene film after transferring the free-standing graphene layer to a functional substrate, degrade the physical and electrical properties of the corresponding electronic devices. Here, we introduced titanium as a superior adhesion layer for fabricating wrinkle-free graphene films that is highly applicable to flexible and transparent electronic devices. The Ti layer does not influence the electronic performance of the functional substrates. Experimental and theoretical investigations confirm that the strong chemical interactions between Ti and any oxygen atoms unintentionally introduced on/within the graphene are responsible for forming the clean, defect-free graphene layer. Our results accelerate the practical application of graphene-related electronic devices with enhanced functionality. The large-area monolayer graphenes were prepared by a simple attachment of the Ti layer with the multi-layer wrinkle-free graphene films. For the first time, the graphene films were addressed for applications of superior bottom electrode for flexible capacitors instead of the novel metals.

Accelerated rehabilitation after arthroscopic Bankart repair for selected cases: a prospective randomized clinical study.

PURPOSE: Increased stress within a certain limit enhances ligament healing and improves joint function. In this prospective randomized clinical trial, we compared the clinical results of early motion versus conventional immobilization after arthroscopic Bankart repair in a selected patient population. TYPE OF STUDY: Prospective randomized clinical trial. METHODS: We performed an arthroscopic Bankart repair using suture anchors in 62 patients with traumatic recurrent anterior instability of the shoulder. Patients were randomized into 2 groups; group 1 (28 patients; mean age, 28 years) was managed with 3 weeks of immobilization using an abduction sling and conventional rehabilitation program, and group 2 (34 patients; mean age, 29 years) was managed with an accelerated rehabilitation program that consisted of staged range of motion and strengthening exercises from the immediate postoperative day. Selection criteria were nonathletes with recurrent anterior shoulder dislocation and a classic Bankart lesion with a robust labrum limited to 1 cm from the midglenoid notch. The patients were followed up for a mean of 31 months (range, 27 to 45 months; standard deviation, 9 months). Analysis of outcome included pain scores at 6 weeks and at final follow-up evaluation, range of motion, return to activity, recurrence rate, patient satisfaction with each rehabilitation program, and shoulder scores assessed by the American Shoulder and Elbow Surgeons Shoulder Index, the rating system of the University of California at Los Angeles, and another scoring system. RESULTS: The recurrence rate was not different between the 2 groups (P =.842). None of the groups developed recurrent dislocation. Two patients from each group were positive for anterior apprehension signs. Patients who underwent accelerated rehabilitation resumed functional range of motion faster (P <.001) and returned earlier to the functional level of activity (P <.001). Accelerated rehabilitation decreased postoperative pain (P =.013), and more patients were satisfied with this program (P <.001). Shoulder scores, return to activity, pain score, and range of motion were not different between the 2 groups at the final follow-up evaluation (P >.05). CONCLUSIONS: Early mobilization of the operated shoulder after arthroscopic Bankart repair does not increase the recurrence rate in a selected group of patients. Although the final outcomes are approximately the same for both groups, the accelerated rehabilitation program promotes functional recovery and reduces postoperative pain, which allows patients an early return to desired activities.

Enhanced transparency, mechanical durability, and antibacterial activity of zinc nanoparticles on glass substrate.

Homogeneously distributed zinc nanoparticles (NPs) on the glass substrate were investigated for the transmittance, mechanical durability, and antibacterial effect. The buffered Ti NPs between Zn NPs and glass substrate were studied for an enhancement of the transmittance and mechanical endurance. The Ti NPs buffered Zn NPs showed a high transmittance of approximately 91.5% (at a wavelength of 550 nm) and a strong antibacterial activity for Staphylococcus aureus and Escherichia coli bacteria. The buffered Ti NPs are attractive for an excellent mechanical endurance of the Zn NPs. The Zn NPs did not require the protection layer to prevent the degradation of the performance for both the antibacterial effect and the transmittance.

High-mobility ambipolar ZnO-graphene hybrid thin film transistors.

In order to combine advantages of ZnO thin film transistors (TFTs) with a high on-off ratio and graphene TFTs with extremely high carrier mobility, we present a facile methodology for fabricating ZnO thin film/graphene hybrid two-dimensional TFTs. Hybrid TFTs exhibited ambipolar behavior, an outstanding electron mobility of 329.7 ± 16.9 cm(2)/V·s, and a high on-off ratio of 10(5). The ambipolar behavior of the ZnO/graphene hybrid TFT with high electron mobility could be due to the superimposed density of states involving the donor states in the bandgap of ZnO thin films and the linear dispersion of monolayer graphene. We further established an applicable circuit model for understanding the improvement in carrier mobility of ZnO/graphene hybrid TFTs.

Novel fabrication of flexible graphene-based chemical sensors with heaters using soft lithographic patterning method.

We have fabricated graphene-based chemical sensors with flexible heaters for the highly sensitive detection of specific gases. We believe that increasing the temperature of the graphene surface significantly enhanced the electrical signal change of the graphene-based channel, and reduced the recovery time needed to obtain a normal state of equilibrium. In addition, a simple and efficient soft lithographic patterning process was developed via surface energy modification for advanced, graphene-based flexible devices, such as gas sensors. As a proof of concept, we demonstrated the high sensitivity of NO2 gas sensors based on graphene nanosheets. These devices were fabricated using a simple soft-lithographic patterning method, where flexible graphene heaters adjacent to the channel of sensing graphene were utilized to control graphene temperature.

Comparison of hydroxyapatite- and porous-coated stems in total hip replacement.

24 patients underwent bilateral hip replacement, using the SROM modular system (Depuy Johnson & Johnson, MA, USA) with the porous-coated sleeve in one hip and an HA-coated sleeve in the other. 20 patients were followed for at least 4 years with clinical and radiographic evaluations. We found no difference between the two sides as regards the time of disappearance of thigh pain and hip scores. Radiographs showed a buttress sign in 18 HA-coated and 15 porous coated stems. There were no differences in the serial bone-remodeling pattern around the proximal sleeve and measurement of wear volume between the two groups. In the short- to medium-term, our findings support the view that the hydroxyapatite-coated femoral stem has no advantages over those with porous coating.