5000 W Slaughter Ln Bldg 2
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Crystal Structure of Hypothetical Fructose-Specific EIIB from Escherichia coli. - Molecules and cells
We have solved the crystal structure of a predicted fructose-specific enzyme IIBfruc from Escherichia coli (EcEIIBfruc) involved in the phosphoenolpyruvate-carbohydrate phosphotransferase system transferring carbohydrates across the cytoplasmic membrane. EcEIIBfruc belongs to a sequence family with more than 5,000 sequence homologues with 25-99% amino-acid sequence identity. It reveals a conventional Rossmann-like Î±-Î²-Î± sandwich fold with a unique Î²-sheet topology. Its C-terminus is longer than its closest relatives and forms an additional Î²-strand whereas the shorter C-terminus is random coil in the relatives. Interestingly, its core structure is similar to that of enzyme IIBcellobiose from E. coli (EcIIBcel) transferring a phosphate moiety. In the active site of the closest EcEIIBfruc homologues, a unique motif CXXGXAHT comprising a P-loop like architecture including a histidine residue is found. The conserved cysteine on this loop may be deprotonated to act as a nucleophile similar to that of EcIIBcel. The conserved histidine residue is presumed to bind the negatively charged phosphate. Therefore, we propose that the catalytic mechanism of EcEIIBfruc is similar to that of EcIIBcelÂ transferring phosphoryl moiety to a specific carbohydrate.
Pharmacopuncture in Korea: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. - Evidence-based complementary and alternative medicine : eCAM
Background. Pharmacopuncture is a new form of acupuncture combining acupuncture with herbal medicine, and it has been used under various conditions in Korea. The aim of this study is to establish clinical evidence for the safety and efficacy of pharmacopuncture in Korea. Methods. We searched 9 databases and two relevant journals up to December 2014 using keywords, such as pharmacopuncture. All randomized, controlled trials evaluating pharmacopuncture under any conditions in Korea were considered. Results. Twenty-nine studies involving 1,211 participants were included. A meta-analysis of two studies on obesity showed that 5 to 8 weeks of pharmacopuncture reduced weight, waist circumference, and body mass index (BMI) more than normal saline injections. In the 5 studies of musculoskeletal conditions, 7 to 30 days of pharmacopuncture had additional effects on the reduction of pain intensity, and this benefit was maintained by limiting analyses to studies with a low risk of bias for randomization and/or allocation concealment. Conclusions. This systematic review suggests the potential of pharmacopuncture for obesity and musculoskeletal diseases. However, it is difficult to recommend pharmacopuncture as an evidence-based treatment because of methodological flaws and small sample sizes of the included studies. Further well-designed trials are needed to draw a definitive conclusion.
Additional Effects of Back-Shu Electroacupuncture and Moxibustion in Cardioprotection of Rat Ischemia-Reperfusion Injury. - Evidence-based complementary and alternative medicine : eCAM
Many preclinical studies show that electroacupuncture (EA) on PC6 and ST36 can reduce infarct size after ischemia-reperfusion (IR) injury. Yet studies to enhance the treatment effect size are limited. The purpose of this study was to explore whether EA has additional myocardial protective effects on an ischemia-reperfusion (IR) injury rat model when back-shu EA and moxibustion are added. SD rats were divided into several groups and treated with either EA only, EA + back-shu EA (B), or EA + B + moxibustion (M) for 5 consecutive days. Transthoracic echocardiography and molecular and immunohistochemical evaluations were performed. It was found that although myocardial infarct areas were significantly lower and cardiac function was also significantly preserved in the three treatment groups compared to the placebo group, there were no additional differences between the three treatment groups. In addition, HSP20 and HSP27 were expressed significantly more in the treatment groups. The results suggest that adding several treatments does not necessarily increase protection. Our study corroborates previous findings that more treatment, such as prolonging EA duration or increasing EA intensity, does not always lead to better results. Other methods of increasing treatment effect size should be explored.
Evaluating validity of various acupuncture device types: a random sequence clinical trial. - BMC complementary and alternative medicine
Although various placebo acupuncture devices have been developed and used in acupuncture research, there is controversy concerning whether these devices really serve as appropriate placebos for control groups.The proposed study is a single-center prospective random sequence participant- and assessor-blinded trial with two parallel arms. A total of 76 participants will be randomly assigned to Group 1 or Group 2 in a 1:1 ratio. Group 1 will consist of Sham Streitberger's needle, Real Streitberger's needle, and Phantom acupuncture session. Group 2 will consist of Park Sham device with real needle, Park Sham device with sham needle, and no treatment session. Participants will have a total of three acupuncture sessions in a day. The primary endpoint is blinding test questionnaire 1. Secondary endpoints are the Bang's blinding index, the Massachusetts General Hospital Acupuncture Sensation Scale index, and physiological data including heart rate, heart rate variability, and skin conductance response.This trial will evaluate the relevance of using placebo acupuncture devices as controls using a validation test procedure.Clinical Research Information Service: KCT0001347 .
Elasticity Modulation of Fibroblast-Derived Matrix for Endothelial Cell Vascular Morphogenesis and Mesenchymal Stem Cell Differentiation. - Tissue engineering. Part A
Biophysical properties of the microenvironment, including matrix elasticity and topography, are known to affect various cell behaviors; however, the specific role of each factor is unclear. In this study, fibroblast-derived matrix (FDM) was used as cell culture substrate and physically modified to investigate the influence of its biophysical property changes on human umbilical vein endothelial cells (HUVECs) and human mesenchymal stem cells (hMSCs) behavior in vitro. These FDMs were physically modified by simply storing them at different temperatures: the one stored at 4Â°C, maintained its original properties, was considered natural FDM, whereas the ones stored at -20Â°C or -80Â°C, exhibited a distinct surface morphology, were considered physically modified FDM. Physical modification induced matrix fiber rearrangement in FDM, forming different microstructures on the surface as characterized by focused ion beam (FIB)-cryoSEM. A significant increase of matrix elasticity was found with physically modified FDMs as determined by atomic force microscopy. HUVEC and hMSC behaviors on these natural and physically modified FDMs were observed and compared with each other and with gelatin-coated coverslips. HUVECs showed a similar adhesion level on these substrates at 3â€‰h, but exhibited different proliferation rates and morphologies at 24â€‰h; HUVECs on natural FDM proliferated relatively slower and assembled to capillary-like structures (CLSs). It is observed that HUVECs assembled to CLSs on natural FDMs are independent on the exogenous growth factors and yet dependent on nonmuscle myosin II activity. This result indicates the important role of matrix mechanical properties in regulating HUVECs vascular morphogenesis. As for hMSCs multilineage differentiation, adipogenesis is improved on natural FDM that with lower matrix elasticity, while osteogenesis is accelerated on physically modified FDMs that with higher matrix elasticity, these results further confirm the crucial role of matrix elasticity on cell fate determination.
Creating Hierarchical Topographies on Fibrous Platforms Using Femtosecond Laser Ablation for Directing Myoblasts Behavior. - ACS applied materials & interfaces
Developing an artificial extracellular matrix that closely mimics the native tissue microenvironment is important for use as both a cell culture platform for controlling cell fate and an in vitro model system for investigating the role of the cellular microenvironment. Electrospinning, one of the methods for fabricating structures that mimic the native ECM, is a promising technique for creating fibrous platforms. It is well-known that align or randomly distributed electrospun fibers provide cellular contact guidance in a single pattern. However, native tissues have hierarchical structures, i.e., topographies on the micro- and nanoscales, rather than a single structure. Thus, we fabricated randomly distributed nanofibrous (720 Â± 80 nm in diameter) platforms via a conventional electrospinning process, and then we generated microscale grooves using a femtosecond laser ablation process to develop engineered fibrous platforms with patterned hierarchical topographies. The engineered fibrous platforms can regulate cellular adhesive morphology, proliferation, and distinct distribution of focal adhesion proteins. Furthermore, confluent myoblasts cultured on the engineered fibrous platforms revealed that the direction of myotube assembly can be controlled. These results indicate that our engineered fibrous platforms may be useful tools in investigating the roles of nano- and microscale topographies in the communication between cells and ECM.
Long-term clinical study and multiscale analysis of in vivo biodegradation mechanism of Mg alloy. - Proceedings of the National Academy of Sciences of the United States of America
There has been a tremendous amount of research in the past decade to optimize the mechanical properties and degradation behavior of the biodegradable Mg alloy for orthopedic implant. Despite the feasibility of degrading implant, the lack of fundamental understanding about biocompatibility and underlying bone formation mechanism is currently limiting the use in clinical applications. Herein, we report the result of long-term clinical study and systematic investigation of bone formation mechanism of the biodegradable Mg-5wt%Ca-1wt%Zn alloy implant through simultaneous observation of changes in element composition and crystallinity within degrading interface at hierarchical levels. Controlled degradation of Mg-5wt%Ca-1wt%Zn alloy results in the formation of biomimicking calcification matrix at the degrading interface to initiate the bone formation process. This process facilitates early bone healing and allows the complete replacement of biodegradable Mg implant by the new bone within 1 y of implantation, as demonstrated in 53 cases of successful long-term clinical study.
Feasibility for non-destructive discrimination of natural and beryllium-diffused sapphires using Raman spectroscopy. - Talanta
Raman spectroscopy based non-destructive discrimination between natural and beryllium-diffused (Be-diffused) sapphires has been attempted. The initial examination of Raman image acquired on a sapphire revealed that microscopic structural and compositional heterogeneity was apparent in the sample, so acquisition of spectra able to represent a whole body of sapphire rather than a localized area was necessary for a reliable discrimination. For this purpose, a wide area illumination (WAI) scheme (illumination area: 28.3mm(2)) providing a large sampling volume was employed to collect representative Raman spectra of sapphires. Upon the diffusion of Be into a sapphire, the band shift originated from varied lattice structure by substitution of Be at cation sites was observed and utilized as a valuable spectral signature for the discrimination. In the domain of principal component (PC) scores, the groups of natural and Be-diffused sapphires were identifiable with minor overlapping and the cross-validated discrimination error was 7.3% when k-Nearest Neighbor (k-NN) was used as a classifier.Copyright Â© 2015 Elsevier B.V. All rights reserved.
Direct and accurate measurement of size dependent wetting behaviors for sessile water droplets. - Scientific reports
The size-dependent wettability of sessile water droplets is an important matter in wetting science. Although extensive studies have explored this problem, it has been difficult to obtain empirical data for microscale sessile droplets at a wide range of diameters because of the flaws resulting from evaporation and insufficient imaging resolution. Herein, we present the size-dependent quantitative change of wettability by directly visualizing the three phase interfaces of droplets using a cryogenic-focused ion beam milling and SEM-imaging technique. With the fundamental understanding of the formation pathway, evaporation, freezing, and contact angle hysteresis for sessile droplets, microdroplets with diameters spanning more than three orders of magnitude on various metal substrates were examined. Wetting nature can gradually change from hydrophobic at the hundreds-of-microns scale to super-hydrophobic at the sub-Î¼m scale, and a nonlinear relationship between the cosine of the contact angle and contact line curvature in microscale water droplets was demonstrated. We also showed that the wettability could be further tuned in a size-dependent manner by introducing regular heterogeneities to the substrate.
Magnesium Corrosion Triggered Spontaneous Generation of H2O2 on Oxidized Titanium for Promoting Angiogenesis. - Angewandte Chemie (International ed. in English)
Although the use of reactive oxygen species (ROS) has been extensively studied, current systems employ external stimuli such as light or electrical energy to produce ROS, which limits their practical usage. In this report, biocompatible metals were used to construct a novel electrochemical system that can spontaneously generate H2O2 without any external light or voltage. The corrosion of Mg transfers electrons to Au-decorated oxidized Ti in an energetically favorable process, and the spontaneous generation of H2O2 in an oxygen reduction reaction was revealed to occur at titanium by combined spectroscopic and electrochemical analyses. The controlled release of H2O2 noticeably enhanced inâ€…vitro angiogenesis even in the absence of growth factors. Finally, a new titanium implant prototype was developed by Mg incorporation, and its potential for promoting angiogenesis was demonstrated.Â© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
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