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Ιαν 08
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- Local and global visual processing and eating diso...
- Comparison of RNA extraction kits and histological...
- Rapid Identification of Pseudomonas spp. via Raman...
- Highly Sensitive Laser Scanning of Photon-Upconver...
- Environment-Sensitive Fluorescent Probe for the Hu...
- Disulfide Linkage Characterization of Disulfide Bo...
- Analysis of Chain Branch of Polyolefins by a New P...
- Cost-Effectiveness of Ranibizumab Versus Afliberce...
- Imaging Local Electric Field Distribution by Plasm...
- Sequential learning of psychomotor and visuospatia...
- Infrared and Raman screening of seized Novel Psych...
- Optional Sub-study to Intraoperative Imaging With ...
- Mitochondrial Respiratory Function in Mammalian Sk...
- Exosome Testing as a Screening Modality for Human ...
- A Phase Ib Trial of Concurrent Cetuximab (ERBITUX®...
- Metals, Vol. 6, Pages 15: Casting Alloy Design and...
- Metals, Vol. 6, Pages 14: Effective Synthesis and ...
- Photonics, Vol. 3, Pages 4: Design and Analysis of...
- Metabolites, Vol. 6, Pages 2: Using Molecular Netw...
- Nutrients, Vol. 8, Pages 31: Association of Dietar...
- Materials, Vol. 9, Pages 34: Aminopropyl-Silica Hy...
- JoF, Vol. 2, Pages 5: Pediatric Invasive Candidias...
- Marine Drugs, Vol. 14, Pages 14: Anti-Inflammatory...
- Nanomaterials, Vol. 6, Pages 13: White Light-Emitt...
- Nanomaterials, Vol. 6, Pages 12: The Coupled Photo...
- Materials, Vol. 9, Pages 33: A Critical Evaluation...
- Energies, Vol. 9, Pages 36: Developing a New HSR S...
- Symmetry, Vol. 8, Pages 2: Natural Abundance Isoto...
- Children, Vol. 3, Pages 1: Learning Lessons from A...
- Toxics, Vol. 4, Pages 1: Farmers’ Exposure to Pest...
- Annual Review of Cybertherapy and Telemedicine 2015
- Researchers Face Potential Danger from Protein Par...
- Study finds cerebrovascular disease to be major de...
- Water, Vol. 8, Pages 18: A Reliability Analysis of...
- Viruses, Vol. 8, Pages 13: The Influenza Virus H5N...
- Entropy, Vol. 18, Pages 22: Increment Entropy as a...
- Animals, Vol. 6, Pages 5: Welfare Conditions of Do...
- Viruses, Vol. 8, Pages 14: Metaviromics of Namib D...
- Buildings, Vol. 6, Pages 3: Assessment of the Perf...
- Entropy, Vol. 18, Pages 23: Long Range Dependence ...
- IJERPH, Vol. 13, Pages 116: Regional Differences i...
- IJERPH, Vol. 13, Pages 113: Unemployment Rate, Smo...
- IJERPH, Vol. 13, Pages 115: Descriptive Characteri...
- Cancer cell identification by bi-color ZnO and TiO...
- Real-time endoscopic Raman spectroscopy for in viv...
- IJMS, Vol. 17, Pages 77: Revealing the Effects of ...
- IJMS, Vol. 17, Pages 72: MiRNA-Target Interaction ...
- IJMS, Vol. 17, Pages 71: Anti-Oncogenic gem-Dihydr...
- IJMS, Vol. 17, Pages 76: Antiproliferative Activit...
- IJMS, Vol. 17, Pages 73: NLRP3 Upregulation in Ret...
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Ιαν 08
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Αναζήτηση αυτού του ιστολογίου
Παρασκευή 8 Ιανουαρίου 2016
Local and global visual processing and eating disorder traits: An event-related potential study
Source:Biological Psychology
Author(s): Jennifer Moynihan, Mark Rose, Jose van Velzen, Jan de Fockert
Recent studies have suggested that individuals with eating disorders show a stronger local processing bias and/or a weaker global bias in visual processing than typical individuals. In this study, healthy participants with varying scores on the Eating Disorder Examination Questionnaire (EDE-Q) performed the Navon task, a standard task of local and global visual processing, whilst electrophysiological measures were recorded. Global stimuli were presented that were made up of many local parts, and the information between levels was either compatible or incompatible. Participants were instructed to report the identity of either a global or a local target shape, while ignoring the other level. Higher EDE-Q scores were associated with enhanced amplitude of the P3 component during local visual processing, as well as greater P1 amplitude during local incompatible trials. These findings support the claim that eating disorders are associated with differences in local and global visual processing.
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Comparison of RNA extraction kits and histological stains for laser capture microdissected prostate tissue
Laser capture microdissection offers unique possibilities for the isolation of specific cell populations or histological structures. However, isolation of RNA from microdissected tissue is challenging due to d...
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Rapid Identification of Pseudomonas spp. via Raman Spectroscopy Using Pyoverdine as Capture Probe
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Highly Sensitive Laser Scanning of Photon-Upconverting Nanoparticles on a Macroscopic Scale
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Environment-Sensitive Fluorescent Probe for the Human Ether-a-go-go-Related Gene Potassium Channel
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Disulfide Linkage Characterization of Disulfide Bond-Containing Proteins and Peptides by Reducing Electrochemistry and Mass Spectrometry
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Analysis of Chain Branch of Polyolefins by a New Proton NMR Approach
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Cost-Effectiveness of Ranibizumab Versus Aflibercept for Macular Edema Secondary to Branch Retinal Vein Occlusion: A UK Healthcare Perspective
Abstract
Introduction
Ranibizumab and aflibercept are anti-vascular endothelial growth factor agents licensed for the treatment of visual impairment due to macular edema secondary to branch retinal vein occlusion (BRVO). The aim of this study was to estimate, from a UK healthcare payer's perspective, the cost-effectiveness of ranibizumab versus aflibercept in this indication.
Methods
A Markov model was used to simulate the outcomes and costs of treating BRVO. Patient baseline characteristics and efficacy data for ranibizumab were obtained from the BRAVO trial. The relative efficacy of aflibercept was derived from a published network meta-analysis. Injection frequencies were derived from ranibizumab and aflibercept studies included in the network meta-analysis. Health states were defined by increments of 10 letters in best corrected visual acuity (BCVA). Patients could gain or lose a maximum of two health states between cycles. The first cycle was 6 months, followed by monthly cycles. Different utility values were assigned to the better-seeing and worse-seeing eyes based on BCVA. A 2-year treatment time frame and a lifetime time horizon were used. Future costs and health outcomes were discounted at 3.5% per annum. Sensitivity analyses were used to test the robustness of the model.
Results
The lifetime cost per patient treated was £15,273 with ranibizumab and £17,347 with aflibercept. Ranibizumab was dominant over aflibercept, producing incremental health gains of 0.0120 quality-adjusted life-years (QALYs) and cost savings of £2074. Net monetary benefit for ranibizumab at a willingness-to-pay threshold of £20,000/QALY was £2314. Sensitivity analyses showed that the results were robust to variations in model parameters.
Conclusions
Ranibizumab provides greater health gains at a lower overall cost than aflibercept in the treatment of visual impairment due to macular edema secondary to BRVO. Ranibizumab is therefore cost-effective from a UK healthcare payer's perspective.
Funding
Novartis Pharma AG, Basel, Switzerland
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Imaging Local Electric Field Distribution by Plasmonic Impedance Microscopy
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Sequential learning of psychomotor and visuospatial skills for laparoscopic suturing and knot tying – study protocol for a randomized controlled trial “The shoebox study”
Background: Laparoscopy training has become an integral part of surgical education. Suturing and knot tying is a basic, yet inherent part of many laparoscopic operations, and should be mastered prior to operating on patients. One common and standardized suturing technique is the C-loop technique. In the standard training setting, on a box trainer, the trainee learns the psychomotor movements of the task and the laparoscopic visuospatial orientation simultaneously. Learning the psychomotor and visuospatial skills separately and sequentially may offer a more time-efficient alternative to the current standard of training. Methods: This is a monocentric, two-arm randomized controlled trial. The participants are medical students in their clinical years (third to sixth year) at Heidelberg University who have not previously partaken in a laparoscopic training course lasting more than 2 hours. A total of 54 students are randomized into one of two arms in a 1:1 ratio to sequential learning (group 1) or control (group 2). Both groups receive a standardized introduction to the training center, laparoscopic instruments, and C-loop technique. Group 1 learn the C-loop using a transparent shoebox, thus only learning the psychomotor skills. Once they reach proficiency, they then perform the same knot tying procedure on a box trainer with standard laparoscopic view, where they combine their psychomotor skills with the visuospatial orientation inherent to laparoscopy. Group 2 learn the C-loop using solely a box trainer with standard laparoscopic view until they reach proficiency. Trainees work in pairs and time is recorded for each attempt. The primary outcome is mean total training time for each group. Secondary endpoints include procedural and knot quality subscore differences. Tertiary endpoints include studying the influence of gender and video game experience on performance.DiscussionThis study addresses whether the learning of the psychomotor and visuospatial aspects of laparoscopic suturing and knot tying is optimal sequentially or simultaneously, by assessing total training time, procedural, and knot quality differences between the two groups. It will improve the efficiency of future laparoscopic suturing courses and may serve as an indicator for laparoscopic training in a broader context, i.e., not only for suturing and knot tying.Trial registrationThis trial was registered on 12 August 2015 with the trial registration number DRKS00008668.
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Infrared and Raman screening of seized Novel Psychoactive Substances: A large scale study of >200 samples.
DOI: 10.1039/C5AN02326B, Paper
The potential of IR absorption and Raman spectroscopy for rapid identification of novel psychoactive substances (NPS) has been tested using a set of 221 unsorted seized samples suspected of containing...
The content of this RSS Feed (c) The Royal Society of Chemistry
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Optional Sub-study to Intraoperative Imaging With ICG Registry
Intervention: Other: data collection
Sponsor: Abramson Cancer Center of the University of Pennsylvania
Recruiting - verified January 2016
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Mitochondrial Respiratory Function in Mammalian Skeletal Muscle
Intervention:
Sponsor: The University of Texas Medical Branch, Galveston
Recruiting - verified December 2015
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Exosome Testing as a Screening Modality for Human Papillomavirus-Positive Oropharyngeal Squamous Cell Carcinoma
Intervention:
Sponsor: New Mexico Cancer Care Alliance
Recruiting - verified January 2016
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A Phase Ib Trial of Concurrent Cetuximab (ERBITUX®) and Intensity Modulated Radiotherapy (IMRT) With Ipilimumab (YERVOY®) in Locally Advanced Head and Neck Cancer
Intervention: Drug: Cetuximab/IMRT Plus Ipilimumab
Sponsors: University of Pittsburgh; National Cancer Institute (NCI)
Recruiting - verified January 2016
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Metals, Vol. 6, Pages 15: Casting Alloy Design and Modification
Castings and the cast metals are among the most important facets creating a foundation for modern life. [...]
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Metals, Vol. 6, Pages 14: Effective Synthesis and Recovery of Silver Nanowires Prepared by Tapered Continuous Flow Reactor for Flexible and Transparent Conducting Electrode
Silver nanowires (AgNWs) with high aspect ratio were obtained utilizing a tapered tubular reactor by the polyol process. The tapered tubular type flow reactor allowed us to obtain nanowires in high yield without defects that is generally encountered in a closed reactor due to excessive shearing for a long time. After reaction the AgNWs were precipitated in the aqueous solution with the aid of a hydrogen bond breaker and were recovered effectively without using a high-cost centrifugation process. Dispersion of the AgNWs were used to prepare transparent conducting electrode (TCE) films by a spray coating method, which showed 86% transmittance and 90 Ωsq−1 sheet resistance.
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Photonics, Vol. 3, Pages 4: Design and Analysis of Enhanced Modulation Response in Integrated Coupled Cavities DBR Lasers Using Photon-Photon Resonance
In the last few decades, various solutions have been proposed to increase the modulation bandwidth and, consequently, the transmission bit-rate of semiconductor lasers. In this manuscript, we discuss a design procedure for a recently proposed laser cavity realized with the monolithic integration of two distributed Bragg reflector (DBR) lasers allowing one to extend the modulation bandwidth. Such an extension is obtained introducing in the dynamic response a photon-photon resonance (PPR) at a frequency higher than the modulation bandwidth of the corresponding single-section laser. Design guidelines will be proposed, and dynamic small and large signal simulations results, calculated using a finite difference traveling wave (FDTW) numerical simulator, will be discussed to confirm the design results. The effectiveness of the design procedure is verified in a structure with PPR frequency at 35 GHz allowing one to obtain an open eye diagram for a non-return-to-zero (NRZ) digital signal up to 80 GHz . Furthermore, the investigation of the rich dynamics of this structure shows that with proper bias conditions, it is possible to obtain also a tunable self-pulsating signal in a frequency range related to the PPR design.
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Metabolites, Vol. 6, Pages 2: Using Molecular Networking for Microbial Secondary Metabolite Bioprospecting
The oceans represent an understudied resource for the isolation of bacteria with the potential to produce novel secondary metabolites. In particular, actinomyces are well known to produce chemically diverse metabolites with a wide range of biological activities. This study characterised spore-forming bacteria from both Scottish and Antarctic sediments to assess the influence of isolation location on secondary metabolite production. Due to the selective isolation method used, all 85 isolates belonged to the phyla Firmicutes and Actinobacteria, with the majority of isolates belonging to the genera Bacillus and Streptomyces. Based on morphology, thirty-eight isolates were chosen for chemical investigation. Molecular networking based on chemical profiles (HR-MS/MS) of fermentation extracts was used to compare complex metabolite extracts. The results revealed 40% and 42% of parent ions were produced by Antarctic and Scottish isolated bacteria, respectively, and only 8% of networked metabolites were shared between these locations, implying a high degree of biogeographic influence upon secondary metabolite production. The resulting molecular network contained over 3500 parent ions with a mass range of m/z 149–2558 illustrating the wealth of metabolites produced. Furthermore, seven fermentation extracts showed bioactivity against epithelial colon adenocarcinoma cells, demonstrating the potential for the discovery of novel bioactive compounds from these understudied locations.
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Nutrients, Vol. 8, Pages 31: Association of Dietary Sugars and Sugar-Sweetened Beverage Intake with Obesity in Korean Children and Adolescents
Few studies have examined the association between dietary sugar intake and obesity in Asian children and adolescents. We evaluated the association of dietary sugar intake and its food source with obesity in Korean children and adolescents. In this cross-sectional analysis, data were obtained from five studies conducted between 2002 and 2011. The study included 2599 children and adolescents who had completed more than three days of dietary records and had anthropometric data. Total sugar intake was higher in girls than in boys (54.3 g for girls and 46.6 g for boys, p < 0.0001). Sugar intake from milk and fruits was inversely associated with overweight or obesity in girls only (OR for overweight, 0.52; 95% CI, 0.32–0.84; p for trend = 0.0246 and OR for obesity, 0.42; 95% CI, 0.23–0.79; p for trend = 0.0113). Sugar-sweetened beverage (SSB) consumption was not associated with obesity in girls, while boys had lower odds ratios for obesity (OR for obesity, 0.52; 95% CI, 0.26–1.05; p for trend = 0.0310). These results suggest that total sugars and SSB intake in Asian children and adolescents remains relatively low and sugar intake from milk and fruits is associated with a decreased risk of overweight or obesity, especially in girls.
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Materials, Vol. 9, Pages 34: Aminopropyl-Silica Hybrid Particles as Supports for Humic Acids Immobilization
A series of aminopropyl-functionalized silica nanoparticles were prepared through a basic two step sol-gel process in water. Prior to being aminopropyl-functionalized, silica particles with an average diameter of 549 nm were prepared from tetraethyl orthosilicate (TEOS), using a Stöber method. In a second step, aminopropyl-silica particles were prepared by silanization with 3-aminopropyltriethoxysilane (APTES), added drop by drop to the sol-gel mixture. The synthesized amino-functionalized silica particles are intended to be used as supports for immobilization of humic acids (HA), through electrostatic bonds. Furthermore, by inserting beside APTES, unhydrolysable mono-, di- or trifunctional alkylsilanes (methyltriethoxy silane (MeTES), trimethylethoxysilane (Me3ES), diethoxydimethylsilane (Me2DES) and 1,2-bis(triethoxysilyl)ethane (BETES)) onto silica particles surface, the spacing of the free amino groups was intended in order to facilitate their interaction with HA large molecules. Two sorts of HA were used for evaluating the immobilization capacity of the novel aminosilane supports. The results proved the efficient functionalization of silica nanoparticles with amino groups and showed that the immobilization of the two tested types of humic acid substances was well achieved for all the TEOS/APTES = 20/1 (molar ratio) silica hybrids having or not having the amino functions spaced by alkyl groups. It was shown that the density of aminopropyl functions is low enough at this low APTES fraction and do not require a further spacing by alkyl groups. Moreover, all the hybrids having negative zeta potential values exhibited low interaction with HA molecules.
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JoF, Vol. 2, Pages 5: Pediatric Invasive Candidiasis: Epidemiology and Diagnosis in Children
Pediatric patients present with differing underlying conditions and cytotoxic therapeutic protocols, so the differing epidemiology of invasive candidiasis in children versus adults is not surprising. Understanding the Candida species epidemiology is critical, as we often begin empiric therapy or therapy before antifungal susceptibilities are known. Reports with newer molecular diagnostic assays for invasive candidiasis are rare and require more study to develop firm pediatric-specific guidance. Antifungal treatment of pediatric candidiasis is reviewed in the context of larger epidemiologic studies and the few trials completed to date.
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Marine Drugs, Vol. 14, Pages 14: Anti-Inflammatory Activity of Tanzawaic Acid Derivatives from a Marine-Derived Fungus Penicillium steckii 108YD142
Chemical investigation of a marine-derived fungus, Penicillium steckii 108YD142, resulted in the discovery of a new tanzawaic acid derivative, tanzawaic acid Q (1), together with four known analogues, tanzawaic acids A (2), C (3), D (4), and K (5). The structures of tanzawaic acid derivatives 1–5 were determined by the detailed analysis of 1D, 2D NMR and LC-MS data, along with chemical methods and literature data analysis. These compounds significantly inhibited nitric oxide (NO) production and the new tanzawaic acid Q (1) inhibited the lipopolysaccharide (LPS)-induced inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) proteins and mRNA expressions in RAW 264.7 macrophages. Additionally, compound 1 reduced the mRNA levels of inflammatory cytokines. Taken together, the results of this study demonstrated that the new tanzawaic acid derivative inhibits LPS-induced inflammation. This is the first report on the anti-inflammatory activity of tanzawaic acid Q (1).
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Nanomaterials, Vol. 6, Pages 13: White Light-Emitting Diodes Based on AgInS2/ZnS Quantum Dots with Improved Bandwidth in Visible Light Communication
Quantum dot white light-emitting diodes (QD-WLEDs) were fabricated from green- and red-emitting AgInS2/ZnS core/shell QDs coated on GaN LEDs. Their electroluminescence (EL) spectra were measured at different currents, ranging from 50 mA to 400 mA, and showed good color stability. The modulation bandwidth of previously prepared QD-WLEDs was confirmed to be much wider than that of YAG:Ce phosphor-based WLEDs. These results indicate that the AgInS2/ZnS core/shell QDs are good color-converting materials for WLEDs and they are capable in visible light communication (VLC).
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Nanomaterials, Vol. 6, Pages 12: The Coupled Photothermal Reaction and Transport in a Laser Additive Metal Nanolayer Simultaneous Synthesis and Pattering for Flexible Electronics
The Laser Direct Synthesis and Patterning (LDSP) technology has advantages in terms of processing time and cost compared to nanomaterials-based laser additive microfabrication processes. In LDSP, a scanning laser on the substrate surface induces chemical reactions in the reactive liquid solution and selectively deposits target material in a preselected pattern on the substrate. In this study, we experimentally investigated the effect of the processing parameters and type and concentration of the additive solvent on the properties and growth rate of the resulting metal film fabricated by this LDSP technology. It was shown that reactive metal ion solutions with substantial viscosity yield metal films with superior physical properties. A numerical analysis was also carried out the first time to investigate the coupled opto-thermo-fluidic transport phenomena and the effects on the metal film growth rate. To complete the simulation, the optical properties of the LDSP deposited metal film with a variety of thicknesses were measured. The characteristics of the temperature field and the thermally induced flow associated with the moving heat source are discussed. It was shown that the processing temperature range of the LDSP is from 330 to 390 K. A semi-empirical model for estimating the metal film growth rate using this process was developed based on these results. From the experimental and numerical results, it is seen that, owing to the increased reflectivity of the silver film as its thickness increases, the growth rate decreases gradually from about 40 nm at initial to 10 nm per laser scan after ten scans. This self-controlling effect of LDSP process controls the thickness and improves the uniformity of the fabricated metal film. The growth rate and resulting thickness of the metal film can also be regulated by adjustment of the processing parameters, and thus can be utilized for controllable additive nano/microfabrication.
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Materials, Vol. 9, Pages 33: A Critical Evaluation of the Influence of the Dark Exchange Current on the Performance of Dye-Sensitized Solar Cells
The influence of the thickness of the nanostructured, mesoporous TiO2 film on several parameters determining the performance of a dye-sensitized solar cell is investigated both experimentally and theoretically. We pay special attention to the effect of the exchange current density in the dark, and we compare the values obtained by steady state measurements with values extracted from small perturbation techniques. We also evaluate the influence of exchange current density, the solar cell ideality factor, and the effective absorption coefficient of the cell on the optimal film thickness. The results show that the exchange current density in the dark is proportional to the TiO2 film thickness, however, the effective absorption coefficient is the parameter that ultimately defines the ideal thickness. We illustrate the importance of the exchange current density in the dark on the determination of the current–voltage characteristics and we show how an important improvement of the cell performance can be achieved by decreasing values of the total series resistance and the exchange current density in the dark.
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Energies, Vol. 9, Pages 36: Developing a New HSR Switching Node (SwitchBox) for Improving Traffic Performance in HSR Networks
High availability is crucial for industrial Ethernet networks as well as Ethernet-based control systems such as automation networks and substation automation systems (SAS). Since standard Ethernet does not support fault tolerance capability, the high availability of Ethernet networks can be increased by using redundancy protocols. Various redundancy protocols for Ethernet networks have been developed and standardized, such as rapid spanning tree protocol (RSTP), media redundancy protocol (MRP), parallel redundancy protocol (PRP), high-availability seamless redundancy (HSR) and others. RSTP and MRP have switchover delay drawbacks. PRP provides zero recovery time, but requires a duplicate network infrastructure. HSR operation is similar to PRP, but HSR uses a single network. However, the standard HSR protocol is mainly applied to ring-based topologies and generates excessively unnecessary redundant traffic in the network. In this paper, we develop a new switching node for the HSR protocol, called SwitchBox, which is used in HSR networks in order to support any network topology and significantly reduce redundant network traffic, including unicast, multicast and broadcast traffic, compared with standard HSR. By using the SwitchBox, HSR not only provides seamless communications with zero switchover time in case of failure, but it is also easily applied to any network topology and significantly reduces unnecessary redundant traffic in HSR networks.
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Symmetry, Vol. 8, Pages 2: Natural Abundance Isotopic Chirality in the Reagents of the Soai Reaction
Isotopic chirality influences sensitively the enantiomeric outcome of the Soai asymmetric autocatalysis. Therefore magnitude and eventual effects of isotopic chirality caused by natural abundance isotopic substitution (H, C, O, Zn) in the reagents of the Soai reaction were analyzed by combinatorics and probability calculations. Expectable enantiomeric excesses were calculated by the Pars–Mills equation. It has been found that the chiral isotopic species formed by substitution in the otherwise achiral reagents provide enantiomeric excess (e.e.) levels that are higher than the sensitivity threshold of the Soai autocatalysis towards chiral induction. Consequently, possible chiral induction exerted by these e.e. values should be taken into account in considerations regarding the molecular events and the mechanism of the chiral induction in the Soai reaction.
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Children, Vol. 3, Pages 1: Learning Lessons from Adverse Drug Reactions in Children
Drug toxicity is, unfortunately, a significant problem in children both in the hospital and in the community. Drug toxicity in children is different to that seen in adults. At least one in 500 children will experience an adverse drug reaction each year. For children in hospital, the risk is far greater (one in ten). Additionally, different and sometimes unique adverse drug reactions are seen in the paediatric age groups. Some of the major cases of drug toxicity historically have occurred in neonates. It is important that we understand the mechanism of action of adverse drug reactions. Greater understanding alongside rational prescribing should hopefully reduce drug toxicity in children in the future.
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Toxics, Vol. 4, Pages 1: Farmers’ Exposure to Pesticides: Toxicity Types and Ways of Prevention
Synthetic pesticides are extensively used in agriculture to control harmful pests and prevent crop yield losses or product damage. Because of high biological activity and, in certain cases, long persistence in the environment, pesticides may cause undesirable effects to human health and to the environment. Farmers are routinely exposed to high levels of pesticides, usually much greater than those of consumers. Farmers' exposure mainly occurs during the preparation and application of the pesticide spray solutions and during the cleaning-up of spraying equipment. Farmers who mix, load, and spray pesticides can be exposed to these chemicals due to spills and splashes, direct spray contact as a result of faulty or missing protective equipment, or even drift. However, farmers can be also exposed to pesticides even when performing activities not directly related to pesticide use. Farmers who perform manual labor in areas treated with pesticides can face major exposure from direct spray, drift from neighboring fields, or by contact with pesticide residues on the crop or soil. This kind of exposure is often underestimated. The dermal and inhalation routes of entry are typically the most common routes of farmers' exposure to pesticides. Dermal exposure during usual pesticide handling takes place in body areas that remain uncovered by protective clothing, such as the face and the hands. Farmers' exposure to pesticides can be reduced through less use of pesticides and through the correct use of the appropriate type of personal protective equipment in all stages of pesticide handling.
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Researchers Face Potential Danger from Protein Particles in the Lab
α-Syn is purified and assembled in test tubes into fibrils that are used to investigate/mimic PD pathogenesis in model animals ranging from worms (c. elegans) to rodents and non-human primates in a large number of laboratories. These laboratories typically contain surfaces and non-disposable items made from plastic, glass, aluminum, or stainless steel. These items are often rough, with areas that cannot be completely cleaned by wiping. Therefore, it is important to minimize contamination through effective cleaning procedures.
"Several teams, including ours, demonstrated that fibrillar α-Syn propagate from one cell, including neurons, to another and amplify during this propagation process mimicking prion particle behavior. These observations suggest that fibrillar α-Syn is not innocuous," explained lead investigator Ronald Melki, PhD, Director of Research at the Paris-Saclay Institute of Neurosciences, CNRS, Gif-sur-Yvette, France.
Researchers applied a solution of fluorescently-labeled fibrils and ribbons of α-Syn to roughened surfaces mimicking laboratory conditions. The droplets were easily visible to the eye and could be assessed by their fluorescence.
Five cleaning solutions were tested: 1) sodium hypochlorite (20,000 ppm); 2) sodium hydroxide (1N), 3) sodium dodecyl sulfate (SDS, 1%, W/V); 4) Hellmanex (1%, V/V); and 5) TFD4 (1%, V/V). As a control, the surfaces were washed with just commercially prepared pure water. After cleaning, the amount of small assemblies, fibrils, and ribbons of α-Syn remaining on the surfaces was measured by fluorescence. To evaluate whether the α-Syn fibrils that were washed off the surfaces were destroyed, fibrils and ribbons were incubated in the various cleaning solutions for one hour and the amount of remaining fibrils was measured.
The researchers found that the commercial detergents Hellmanex, and SDS (1%, W/V) are the most suitable cleaning reagents for removal and neutralization of α -Syn seeds from contaminated surfaces. However, solutions of sodium hypochlorite (20,000 ppm) or sodium hydroxide (1N), previously shown to diminish prion infectivity, were ineffective. Plain water was similarly ineffective.
As the result of this investigation, the research teams have implemented "Laboratory Standard Operating Procedures for fibrillar α-Syn" to minimize possible contamination. This includes a cleaning procedure that removes and disassembles α-Syn fibrils adsorbed on plastic, glass, aluminum, or stainless steel surfaces as well as recommended disposal procedures for various forms of α-Syn waste. This cleaning method is sufficiently mild to allow efficient decontamination of non-disposable tools in a laboratory.
"We conclude that cleaning procedures relying on the use of detergents that are compatible with most non-disposable tools in a laboratory are simple to implement and highly recommended when working with fibrillar α-Syn in a laboratory setting," stated co-investigator Patrik Brundin, MD, PhD, Editor-in-Chief of the Journal of Parkinson's Disease and Director of the Center for Neurodegenerative Science at Van Andel Research Institute in Grand Rapids, Michigan.
"The procedures we describe remove and inactivate α-Syn fibrillar assemblies to a level where they are undetectable, which significantly improve researchers' safety when handling fibrillar α-Syn. Further work is needed to establish the infectious unit of recombinant α-Syn and the biological efficiency of the cleaning," added co-investigator Luc Bousset, PhD, at the Paris-Saclay Institute of Neurosciences, CNRS.
# # #
NOTES FOR EDITORS
"An efficient procedure for removal and inactivation of alpha-synuclein assemblies from laboratory materials," by Luc Bousset, Patrik Brundin, Anja Bőckmann, Beat Meier and Ronald Melki; (DOI 10.3233/JPD-150691), published in advance of Journal of Parkinson's Disease, Volume 6, Issue 1 (March 2016), published by IOS Press. The article is openly available here.
For additional information contact Daphne Watrin, IOS Press, at +31 20 688 3355, d.watrin@iospress.nl. Journalists wishing to interview the authors should contact Luc Bousset at +33-16982-3479; luc.bousset@inaf.cnrs-gif.fr, or Ronald Melki at +33-16982-3503; melki@lebs.cnrs-gif.fr.
ABOUT THE JOURNAL OF PARKINSON'S DISEASE (JPD)
Launched in 2011 the Journal of Parkinson's Disease is dedicated to providing an open forum for original research in basic science, translational research and clinical medicine that will expedite our fundamental understanding and improve treatment of Parkinson's disease. The journal is international and multidisciplinary and aims to promote progress in the epidemiology, etiology, genetics, molecular correlates, pathogenesis, pharmacology, psychology, diagnosis and treatment of Parkinson's disease. It publishes research reports, reviews, short communications, and letters-to-the-editor and offers very rapid publication and an affordable open access option.
ABOUT IOS PRESS
Commencing its publishing activities in 1987, IOS Press serves the information needs of scientific and medical communities worldwide. IOS Press now (co-)publishes over 100 international journals and about 75 book titles each year on subjects ranging from computer sciences and mathematics to medicine and the natural sciences.
IOS Press continues its rapid growth, embracing new technologies for the timely dissemination of information. All journals are available electronically and an e-book platform was launched in 2005.
Headquartered in Amsterdam with satellite offices in the USA, Germany, India and China, IOS Press has established several strategic co-publishing initiatives. Notable acquisitions included Delft University Press in 2005 and Millpress Science Publishers in 2008.
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Study finds cerebrovascular disease to be major determinant of psychosis in patients with Alzheimer’s disease
But the pathological mechanisms that underlie psychotic symptoms are unclear, limiting the ability to manage and treat them. Some studies have suggested they are related to the underlying causes of Alzheimer's disease such as the protein deposits found in the brains of Alzheimer's patients, but others found no correlation.
A study published today in the Journal of Alzheimer's Disease found that cerebrovascular disease is a major determinant of psychosis in people with Alzheimer's disease. Cerebrovascular disease is a group of conditions that restrict the circulation of blood to the brain.
Using data from the National Alzheimer's Coordinating Centre database collected from 29 Alzheimer's disease centres in the United States between 2005 and 2012, researchers led by Dr. Corinne Fischer, a psychiatrist and researcher at St. Michael's Hospital, analyzed autopsy data from 1,073 people.
Of the 890 people who had been clinically diagnosed with Alzheimer's while they were alive, the people most likely to be psychotic were those whose autopsies showed they had more physical signs of Alzheimer's such as neuritic plaques (protein deposits) and neurofibrillary tangles (twisted fibers found inside brain cells).
But when they looked at the 728 people whose autopsies confirmed they had Alzheimer's, those with psychosis did not show increased physical evidence of Alzheimer's disease. . Alzheimer's can only be confirmed through an autopsy, so some patients in the clinically diagnosed group had been misdiagnosed with Alzheimer's.
In both groups of patients, psychosis correlated significantly with Lewy bodies, abnormal protein aggregates found in nerve cells of patients with Parkinson's disease. This was not an unexpected finding since psychosis is prominent when dementia accompanies Parkinson's disease.
What was entirely unexpected was the prominent role in psychosis of vascular risk factors (hypertension, diabetes, age at quitting smoking) and cerebral injuries related to small vessel disease,
About 19 per cent of people with Alzheimer's who live in the community (rather than in institutions) are thought to have delusions and 14 per cent have hallucinations. Psychotic symptoms are significant in Alzheimer's patients because they have been shown to be associated with increased burden on caregivers, increased functional decline and more rapid progression of the disease.
This study received funding from the Canadian Institutes of Health Research.
Fischer CE, Qian W, Schweizer TA, Millikin CP, Ismail Z, Smith EE, Lix LM, Shelton P, Munoz DG (2016) Lewy Bodies, Vascular Risk Factors, and Subcortical Arteriosclerotic Leukoencephalopathy, but not Alzheimer Pathology, are Associated with Development of Psychosis in Alzheimer's Disease. J Alzheimers Dis, doi: 10.3233/JAD-150606.
About St. Michael's Hospital
St. Michael's Hospital provides compassionate care to all who enter its doors. The hospital also provides outstanding medical education to future health care professionals in more than 23 academic disciplines. Critical care and trauma, heart disease, neurosurgery, diabetes, cancer care, and care of the homeless are among the Hospital's recognized areas of expertise. Through the Keenan Research Centre and the Li Ka Shing International Healthcare Education Center, which make up the Li Ki Sheng Knowledge Institute, research and education at St. Michael's Hospital are recognized and make an impact around the world. Founded in 1892, the hospital is fully affiliated with the University of Toronto.
Media contact:
For more information or to arrange an interview with Dr. Fischer, please contact:
Leslie Shepherd
Manager, Media Strategy,
St. Michael's Hospital
Phone: 416-864-6094 or 416-200-4087
shepherdl@smh.ca
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Water, Vol. 8, Pages 18: A Reliability Analysis of a Rainfall Harvesting System in Southern Italy
Rainwater harvesting (RWH) may be an effective alternative water supply solution in regions affected by water scarcity. It has recently become a particularly important option in arid and semi-arid areas (like Mediterranean basins), mostly because of its many benefits and affordable costs. This study provides an analysis of the reliability of using a rainwater harvesting system to supply water for toilet flushing and garden irrigation purposes, with reference to a single-family home in a residential area of Sicily (Southern Italy). A flushing water demand pattern was evaluated using water consumption data collected from a sample of residential customers during an extended measurement campaign. A daily water balance simulation of the rainwater storage tank was performed, and the yield-after-spillage algorithm was used to define the tank release rule. The model's performance was evaluated using rainfall data from more than 100 different sites located throughout the Sicilian territory. This regional analysis provided annual reliability curves for the system as a function of mean annual precipitation, which have practical applications in this area of study. The uncertainty related to the regional model predictions was also assessed. A cost-benefit analysis highlighted that the implementation of a rainwater harvesting system in Sicily can provide environmental and economic advantages over traditional water supply methods. In particular, the regional analysis identified areas where the application of this system would be most effective.
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Viruses, Vol. 8, Pages 13: The Influenza Virus H5N1 Infection Can Induce ROS Production for Viral Replication and Host Cell Death in A549 Cells Modulated by Human Cu/Zn Superoxide Dismutase (SOD1) Overexpression
Highly pathogenic H5N1 infections are often accompanied by excessive pro-inflammatory response, high viral titer, and apoptosis; as such, the efficient control of these infections poses a great challenge. The pathogenesis of influenza virus infection is also related to oxidative stress. However, the role of endogenic genes with antioxidant effect in the control of influenza viruses, especially H5N1 viruses, should be further investigated. In this study, the H5N1 infection in lung epithelial cells decreased Cu/Zn superoxide dismutase (SOD1) expression at mRNA and protein levels. Forced SOD1 expression significantly inhibited the H5N1-induced increase in reactive oxygen species, decreased pro-inflammatory response, prevented p65 and p38 phosphorylation, and impeded viral ribonucleoprotein nuclear export and viral replication. The SOD1 overexpression also rescued H5N1-induced cellular apoptosis and alleviated H5N1-caused mitochondrial dysfunction. Therefore, this study described the role of SOD1 in the replication of H5N1 influenza virus and emphasized the relevance of this enzyme in the control of H5N1 replication in epithelial cells. Pharmacological modulation or targeting SOD1 may open a new way to fight H5N1 influenza virus.
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Entropy, Vol. 18, Pages 22: Increment Entropy as a Measure of Complexity for Time Series
Entropy has been a common index to quantify the complexity of time series in a variety of fields. Here, we introduce an increment entropy to measure the complexity of time series in which each increment is mapped onto a word of two letters, one corresponding to the sign and the other corresponding to the magnitude. Increment entropy (IncrEn) is defined as the Shannon entropy of the words. Simulations on synthetic data and tests on epileptic electroencephalogram (EEG) signals demonstrate its ability of detecting abrupt changes, regardless of the energetic (e.g., spikes or bursts) or structural changes. The computation of IncrEn does not make any assumption on time series, and it can be applicable to arbitrary real-world data.
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Animals, Vol. 6, Pages 5: Welfare Conditions of Donkeys in Europe: Initial Outcomes from On-Farm Assessment
This paper is a baseline study to present the initial outcomes of data collected in a sample of EU donkey farms using the AWIN welfare assessment protocol for donkeys, comprehensive of 22 valid, reliable and feasible animal-based indicators. A total of 20 donkey facilities (N = 12 in Italy and N = 8 in United Kingdom) were visited and 278 donkeys of different breed, aged 2–45 years, were assessed. Three assessors underwent a common training period to learn how to perform and score all the indicators included in the protocol. Data was collected using digitalized systems and downloaded to a database. A descriptive statistic for each welfare indicator was calculated. The authors found recurrent issues: 25% of donkeys were moderately over weight; although most of the assessed animals had good quality hoof care, 15.16% of them presented some signs of neglect, such as overgrowth and/or incorrect trimming; 18.05% of donkeys showed an avoidance reaction to an approaching human in the avoidance distance test. The protocol has proven to be applicable in different management conditions and for donkeys of different attitude.
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Viruses, Vol. 8, Pages 14: Metaviromics of Namib Desert Salt Pans: A Novel Lineage of Haloarchaeal Salterproviruses and a Rich Source of ssDNA Viruses
Viral communities of two different salt pans located in the Namib Desert, Hosabes and Eisfeld, were investigated using a combination of multiple displacement amplification of metaviromic DNA and deep sequencing, and provided comprehensive sequence data on both ssDNA and dsDNA viral community structures. Read and contig annotations through online pipelines showed that the salt pans harbored largely unknown viral communities. Through network analysis, we were able to assign a large portion of the unknown reads to a diverse group of ssDNA viruses. Contigs belonging to the subfamily Gokushovirinae were common in both environmental datasets. Analysis of haloarchaeal virus contigs revealed the presence of three contigs distantly related with His1, indicating a possible new lineage of salterproviruses in the Hosabes playa. Based on viral richness and read mapping analyses, the salt pan metaviromes were novel and most closely related to each other while showing a low degree of overlap with other environmental viromes.
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Buildings, Vol. 6, Pages 3: Assessment of the Performance of a Ventilated Window Coupled with a Heat Recovery Unit through the Co-Heating Test
The aim of the article is to describe the results of an experimental campaign based on the assessment of a heat recovery unit coupled with a dynamic window. Two fully monitored and calibrated outdoor test cells are used, in order to evaluate the energy performance and the related thermal comfort. The former presents a traditional window with double-glazing, aluminum frame and indoor blind and a centrifugal extractor for the air circulation. The latter is equipped with a dynamic window with ventilated and blinded double-glazing provided with a heat exchanger. The connection of the dynamic window and heat recovery unit provides different actions: heat recovery; heat transfer reduction; pre-heating before the exchanger. Different operating configurations allowed the trends of the dynamic system to be assessed in different seasons in terms of energy saving, thermal comfort behavior and energy efficiency. The results showed an overall lower consumption of the innovative system, both in winter and summer, with 20% and 15% energy saving, respectively. In general, the dynamic system provided the best comfort conditions, even if it involves a worse behavior than expected, in the summer season.
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Entropy, Vol. 18, Pages 23: Long Range Dependence Prognostics for Bearing Vibration Intensity Chaotic Time Series
According to the chaotic features and typical fractional order characteristics of the bearing vibration intensity time series, a forecasting approach based on long range dependence (LRD) is proposed. In order to reveal the internal chaotic properties, vibration intensity time series are reconstructed based on chaos theory in phase-space, the delay time is computed with C-C method and the optimal embedding dimension and saturated correlation dimension are calculated via the Grassberger–Procaccia (G-P) method, respectively, so that the chaotic characteristics of vibration intensity time series can be jointly determined by the largest Lyapunov exponent and phase plane trajectory of vibration intensity time series, meanwhile, the largest Lyapunov exponent is calculated by the Wolf method and phase plane trajectory is illustrated using Duffing-Holmes Oscillator (DHO). The Hurst exponent and long range dependence prediction method are proposed to verify the typical fractional order features and improve the prediction accuracy of bearing vibration intensity time series, respectively. Experience shows that the vibration intensity time series have chaotic properties and the LRD prediction method is better than the other prediction methods (largest Lyapunov, auto regressive moving average (ARMA) and BP neural network (BPNN) model) in prediction accuracy and prediction performance, which provides a new approach for running tendency predictions for rotating machinery and provide some guidance value to the engineering practice.
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IJERPH, Vol. 13, Pages 116: Regional Differences in Correlates of Daily Walking among Middle Age and Older Australian Rural Adults: Implications for Health Promotion
Rural Australians are less physically active than their metropolitan counterparts, and yet very little is known of the candidate intervention targets for promoting physical activity in rural populations. As rural regions are economically, socially and environmentally diverse, drivers of regular physical activity are likely to vary between regions. This study explored the region-specific correlates of daily walking among middle age and older adults in rural regions with contrasting dominant primary industries. Participants were recruited through print and electronic media, primary care settings and community organisations. Pedometers were worn by 153 adults for at least four days, including a weekend day. A questionnaire identified potential intra-personal, social and environmental correlates of physical activity, according to a social ecological framework. Regression modelling identified independent correlates of daily walking separately in the two study regions. In one region, there were independent correlates of walking from all levels of the social ecological framework. In the other region, significant correlates of daily walking were almost all demographic (age, education and marital status). Participants living alone were less likely to be physically active regardless of region. This study highlights the importance of considering region-specific factors when designing strategies for promoting regular walking among rural adults.
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IJERPH, Vol. 13, Pages 113: Unemployment Rate, Smoking in China: Are They Related?
Background: Studies on the relationship between unemployment rate and smoking have yielded mixed results. The issue in China has not been studied. This study aims to examine the influence of unemployment rate on smoking in China. Methods: Logit model and two-stage least squares (2SLS) estimation were used to estimate the effects. Estimations were done for 4585 individual over 45 using data from China Health and Retirement Longitudinal Study conducted in Zhejiang and Gansu provinces in 2008 and 2012. Results: A percent increase in the unemployment rate resulted in the increase in the likelihood of smoking by a combined 9.1 percent for those who smoked including a 2.9% increase for those who smoked 1–10 cigarettes per day; a 2.8% increase for those who smoked 11–20 cigarettes per day; and a 3.4% increase for those who smoked 20 cigarettes or more per day. The effects were stronger for those who were employed. Non-drinkers were more likely to engage in smoking with increased unemployment rate. 2SLS estimation revealed the same association. Conclusions: The unemployment rate was positively associated with smoking behavior. Smoking control and intervention strategies should focus on both the individual′s characteristics and the physical environment in which unemployment rate tend to rise.
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IJERPH, Vol. 13, Pages 115: Descriptive Characteristics of Surface Water Quality in Hong Kong by a Self-Organising Map
In this study, principal component analysis (PCA) and a self-organising map (SOM) were used to analyse a complex dataset obtained from the river water monitoring stations in the Tolo Harbor and Channel Water Control Zone (Hong Kong), covering the period of 2009–2011. PCA was initially applied to identify the principal components (PCs) among the nonlinear and complex surface water quality parameters. SOM followed PCA, and was implemented to analyze the complex relationships and behaviors of the parameters. The results reveal that PCA reduced the multidimensional parameters to four significant PCs which are combinations of the original ones. The positive and inverse relationships of the parameters were shown explicitly by pattern analysis in the component planes. It was found that PCA and SOM are efficient tools to capture and analyze the behavior of multivariable, complex, and nonlinear related surface water quality data.
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Cancer cell identification by bi-color ZnO and TiO2 nanowires
Semiconductor nanocomposites provide advantages beyond the capability of typical fluorescent materials for cancer detection. In this work, nanowire-based probes with dual color channels are employed to demonstrate the capacity of cancer cell detection. Purple emitting ZnO/antibody probes are applied to detect cancer cells and meanwhile TiO2/antibody probes with green light emission are applied to identify normal fibroblast cells. A series of quantitative analyses are conducted to verify the correlation between the concentrations of ZnO and TiO2 probes, cell numbers, and peak intensities of the PL spectra. The results provide a quantitative reference for developing nanowire-based cancel cell probes.
The microscopic image of the co-cultured SCC and HS68 cells which are applied with ZnO-EGFR and TiO2-Vimentin nanoprobes under the illumination of a laser. Among them, purple emission from ZnO, green emission from TiO2 can be seen. The position of SCC and Hs68 cells can be easily verified with the help of the two probes.
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Real-time endoscopic Raman spectroscopy for in vivo early lung cancer detection
Currently the most sensitive method for localizing lung cancers in central airways is autofluorescence bronchoscopy (AFB) in combination with white light bronchoscopy (WLB). The diagnostic accuracy of WLB + AFB for high grade dysplasia (HGD) and carcinoma in situ is variable depending on physician's experience. When WLB + AFB are operated at high diagnostic sensitivity, the associated diagnostic specificity is low. Raman spectroscopy probes molecular vibrations and gives highly specific, fingerprint-like spectral features and has high accuracy for tissue pathology classification. In this study we present the use of a real-time endoscopy Raman spectroscopy system to improve the specificity. A spectrum is acquired within 1 second and clinical data are obtained from 280 tissue sites (72 HGDs/malignant lesions, 208 benign lesions/normal sites) in 80 patients. Using multivariate analyses and waveband selection methods on the Raman spectra, we have demonstrated that HGD and malignant lung lesions can be detected with high sensitivity (90%) and good specificity (65%).
A custom-made endoscopic Raman spectroscopy system has been used to study the Raman spectroscopy properties of lung tissues in vivo in central airways of 80 patients. Multivariate statistical analysis of the acquired spectral data covering various pathologies including normal, inflammation, hyperplasia, metaplasia, mild/moderate/severe dysplasia, carcinoma-in-situ, and invasive cancer suggests that lung cancers and precancerous lesions can be differentiated from benign lesions and normal tissues with high sensitivity (90%) and good specificity (65%).
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IJMS, Vol. 17, Pages 77: Revealing the Effects of Missense Mutations Causing Snyder-Robinson Syndrome on the Stability and Dimerization of Spermine Synthase
Missense mutations in spermine synthase (SpmSyn) protein have been shown to cause the Snyder-Robinson syndrome (SRS). Depending on the location within the structure of SpmSyn and type of amino acid substitution, different mechanisms resulting in SRS were proposed. Here we focus on naturally occurring amino acid substitutions causing SRS, which are situated away from the active center of SpmSyn and thus are not directly involved in the catalysis. Two of the mutations, M35R and P112L, are reported for the first time in this study. It is demonstrated, both experimentally and computationally, that for such mutations the major effect resulting in dysfunctional SpmSyn is the destabilization of the protein. In vitro experiments indicated either no presence or very little amount of the mutant SpmSyn in patient cells. In silico modeling predicted that all studied mutations in this work destabilize SpmSyn and some of them abolish homo-dimer formation. Since dimerization and structural stability are equally important for the wild type function of SpmSyn, it is proposed that the SRS caused by mutations occurring in the N-domain of SpmSyn is a result of dysfunctional mutant proteins being partially unfolded and degraded by the proteomic machinery of the cell or being unable to form a homo-dimer.
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IJMS, Vol. 17, Pages 72: MiRNA-Target Interaction Reveals Cell-Specific Post-Transcriptional Regulation in Mammalian Cell Lines
MicroRNAs are 18–22 nucleotides long, non-coding RNAs that bind transcripts with complementary sequences leading to either mRNA degradation or translational suppression. However, the inherent differences in preferred mode of miRNA regulation among cells of different origin have not been examined. In our previous transcriptome profiling studies, we observed that post-transcriptional regulation can differ substantially depending on the cell in context. Here we examined mechanistic differences in the regulation of a let-7a targeted (wild type) or resistant (mutant) engineered renilla transcript across various mammalian cell lines of diverse origin. Dual luciferase assays show that compared to mutant (mut), the reporter gene containing wild type (wt) let-7a binding sites was efficiently suppressed upon transfection in various cell lines. Importantly, the strength of miRNA regulation varied across the cell lines. Total RNA analysis demonstrates that wt renilla mRNA was expressed to similar or higher levels compared to mut suggesting that translation repression is a predominant mode of miRNA regulation. Nonetheless, transcript degradation was observed in some cell lines. Ago-2 immunoprecipitation show that miRNA repressed renilla mRNA are associated with functional mi-RISC (miRNA-RNA induced silencing complex). Given the immense potential of miRNA as a therapeutic option, these findings highlight the necessity to thoroughly examine the mode of mRNA regulation in order to achieve the beneficial effects in targeting cells.
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IJMS, Vol. 17, Pages 71: Anti-Oncogenic gem-Dihydroperoxides Induce Apoptosis in Cancer Cells by Trapping Reactive Oxygen Species
Organic gem-dihydroperoxides (DHPs) and their derived peroxides have attracted a great deal of attention as potential anti-cancer agents. However, the precise mechanism of their inhibitory effect on tumors is unknown. To determine the mechanism of the inhibitory effects of DHPs, we examined the effects of DHPs on leukemia K562 cells. As a result, certain DHPs used in this study exhibited growth-inhibitory activity according to a clear structure-activity relationship. The most potent DHP, 12AC3O, induced apoptosis in K562 cells, but not in peripheral blood monocytes (PBMCs) or fibroblast cells. 12AC3O induced apoptosis through the intrinsic mitochondrial pathway and thereafter through the extrinsic pathway. The activity of the former pathway was partly attenuated by a JNK inhibitor. Interestingly, 12AC3O induced apoptosis by trapping a large amount of ROS, leading to an extremely lower intracellular ROS level compared with that in the cells in the steady-state condition. These results suggest that an appropriate level of intracellular ROS was necessary for the maintenance of cancer cell growth. DHPs may have a potential to be a novel anti-cancer agent with minimum adverse effects on normal cells.
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IJMS, Vol. 17, Pages 76: Antiproliferative Activity of Double Point Modified Analogs of 1,25-Dihydroxyvitamin D2 Against Human Malignant Melanoma Cell Lines
Vitamin D is a lipid soluble steroid hormone with pleiotropic biological properties, including regulation of cell proliferation, differentiation and apoptosis. As to these desirable anticancer actions, 1,25-dihydroxyvitamins D and analogs have been reported to inhibit the proliferation and to induce differentiation of a wide variety of cancer cell types, including human malignant melanoma. However, there is a need for novel and more efficacious vitamin D analogs, and how best to design such is still an open issue. A series of double point modified (DPM) analogs of 1,25-dihydroxyvitamin D2 (1,25(OH)2D2) induced differentiation of the vitamin D receptor (VDR) positive A375 and VDR negative SK-MEL 188b human malignant melanoma cell lines. Surprisingly, the dose of 1,25(OH)2D2 required to inhibit the proliferation of the A375 melanoma cell line by was several fold lower than that required in the case of 1,25(OH)2D3. To evaluate the impact of the modification in the side chain (additional 22-hydroxyl) and in the A-ring (5,6-trans modification), the regular side-chain of vitamin D2 or D3 was retained in the structure of our analogs. As expected, 5,6-trans modification was advantageous to enhancing the anti-proliferative activity of analogs, but not as a single point modification (SPM). Very unexpectedly, the additional 22-hydroxyl in the side-chain reduced significantly the anti-proliferative activity of both the natural and 5,6-trans series analogs. Finally, an induction of pigmentation in melanoma SK-MEL 188b cells was observed to sensitized cells to the effect of vitamin D analogs.
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IJMS, Vol. 17, Pages 73: NLRP3 Upregulation in Retinal Pigment Epithelium in Age-Related Macular Degeneration
Inflammation and oxidative stress are involved in age-related macular degeneration (AMD) and possibly associated with an activation of neuronal apoptosis inhibitor protein/class II transcription activator of the Major Histocompatibility Complex (MHC)/heterokaryon incompatibility/telomerase-associated protein 1, leucine-rich repeat or nucleotide-binding domain, leucine-rich repeat-containing family, and pyrin domain-containing 3 (NLRP3) inflammasome. In the present study, we used a translational approach to address this hypothesis. In patients with AMD, we observed increased mRNA levels of NLRP3, pro-interleukin-1 beta (IL-1β) and pro-IL-18 in AMD lesions of the retinal pigment epithelium (RPE) and photoreceptor. In vitro, a similar increase was evoked by oxidative stress or lipopolysaccharide (LPS) stimulation in the adult retinal pigment epithelium (ARPE-19) cell line, and the increase was reduced in siRNA transfected cells to knockdown NLRP3. Ultrastructural studies of ARPE-19 cells showed a swelling of the cytoplasm, mitochondrial damage, and occurrence of autophagosome-like structures. NLRP3 positive dots were detected within autophagosome-like structures or in the extracellular space. Next, we used a mouse model of AMD, Ccl2/Cx3cr1 double knockout on rd8 background (DKO rd8) to ascertain the in vivo relevance. Ultrastructural studies of the RPE of these mice showed damaged mitochondria, autophagosome-like structures, and cytoplasmic vacuoles, which are reminiscent of the pathology seen in stressed ARPE-19 cells. The data suggest that the NLRP3 inflammasome may contribute in AMD pathogenesis.
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Αλέξανδρος Γ. Σφακιανάκης Medicine by Alexandros G. Sfakianakis,Anapafseos 5 Agios Nikolaos 72100 Crete Greece,00302841026182,0030693260717...
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heory of COVID-19 pathogenesis Publication date: November 2020Source: Medical Hypotheses, Volume 144Author(s): Yuichiro J. Suzuki ScienceD...
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