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- Editorial Board
- Top-down Modulation of Neural Activity in Anticipa...
- Subscription Page
- Distributed and Overlapping Neural Substrates for ...
- Midcingulate Motor Map and Feedback Detection: Con...
- The Contextual Association Network Activates More ...
- Lying and the Subsequent Desire for Toothpaste: Ac...
- Bodies are Represented as Wholes Rather Than Their...
- Brain Circuitry Supporting Multi-Organ Autonomic O...
- Fulminant hepatitis B as a result of reactivation ...
- Dominant enrichment of phenotypically activated CD...
- Nanopillar films with polyoxometalate-doped polyan...
- Genetically Anchored Fluorescent Probes for Subcel...
- Parents of terror victims. A longitudinal study of...
- Data supporting the regulation of FOXC2 in podocyt...
- Correction: Testing and validating electroanalytic...
- Ascorbic acid supplementation improves skeletal mu...
- Small molecules preventing GAPDH aggregation are t...
- Oxidised LDL induced extracellular trap formation ...
- Continuous attractor network models of grid cell f...
- Prevalence of occult hepatitis C virus infection i...
- The Function of Naringin in Inducing Secretion of ...
- IJMS, Vol. 17, Pages 90: Function and Regulation o...
- IJMS, Vol. 17, Pages 105: Urine Aquaporin-2: A Pro...
- IJMS, Vol. 17, Pages 102: Cellular Pathways in Res...
- IJMS, Vol. 17, Pages 103: Free Radical Scavenging ...
- IJMS, Vol. 17, Pages 104: Fourier Transform Mass S...
- IJMS, Vol. 17, Pages 100: Iron in Multiple Scleros...
- IJMS, Vol. 17, Pages 107: Erdr1 Suppresses Murine ...
- Marine Drugs, Vol. 14, Pages 16: Marine Isonitrile...
- A 70% Ethanol Extract of Mistletoe Rich in Betulin...
- Materials, Vol. 9, Pages 47: Surface Functional Po...
- Energies, Vol. 9, Pages 43: Reliability Analysis a...
- Nutrients, Vol. 8, Pages 45: Effect of Polydextros...
- Antibiotics, Vol. 5, Pages 6: Controversies in Ant...
- Viruses, Vol. 8, Pages 21: Advances and Challenges...
- Applied Sciences, Vol. 6, Pages 18: Fault-Tolerant...
- Materials, Vol. 9, Pages 48: Synthesis, X-ray Stru...
- Antioxidants, Vol. 5, Pages 3: Hydrogen Sulfide, O...
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Ιαν 14
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Αναζήτηση αυτού του ιστολογίου
Πέμπτη 14 Ιανουαρίου 2016
Top-down Modulation of Neural Activity in Anticipatory Visual Attention: Control Mechanisms Revealed by Simultaneous EEG-fMRI
In covert visual attention, frontoparietal attention control areas are thought to issue signals to selectively bias sensory neurons to facilitate behaviorally relevant information and suppress distraction. We investigated the relationship between activity in attention control areas and attention-related modulation of posterior alpha activity using simultaneous electroencephalography (EEG) and functional magnetic resonance imaging in humans during cued visual-spatial attention. Correlating single-trial EEG alpha power with blood-oxygen-level dependent (BOLD) activity, we found that BOLD in the intraparietal sulcus (IPS) and left middle frontal gyrus was inversely correlated with occipital alpha power. Importantly, in IPS, inverse correlations were stronger for alpha within the hemisphere contralateral to the attended hemifield, implicating the IPS in the enhancement of task-relevant sensory areas. Positive BOLD-alpha correlations were observed in sensorimotor cortices and the default mode network, suggesting a mechanism of active suppression over task-irrelevant areas. The magnitude of cue-induced alpha lateralization was positively correlated with BOLD in dorsal anterior cingulate cortex and dorsolateral prefrontal cortex, implicating a role of executive control in attention. These results show that IPS and frontal executive areas are the main sources of biasing influences on task-relevant visual cortex, whereas task-irrelevant default mode network and sensorimotor cortex are inhibited during visual attention.
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Distributed and Overlapping Neural Substrates for Object Individuation and Identification in Visual Short-Term Memory
Object individuation and identification are 2 key processes involved in representing visual information in short-term memory (VSTM). Individuation involves the use of spatial and temporal cues to register an object as a distinct perceptual event relative to other stimuli, whereas object identification involves extraction of featural and related conceptual properties of a stimulus. Together, individuation and identification provide the "what," "where," and "when" of visual perception. In the current study, we asked whether individuation and identification processes are underpinned by distinct neural substrates, and to what extent brain regions that reflect these 2 operations are consistent across encoding, maintenance, and retrieval stages of VSTM. We used functional magnetic resonance imaging to identify brain regions that represent the number of objects (individuation) and/or object features (identification) in an array. Using univariate and multivariate analyses, we found substantial overlap between these 2 operations in the brain. Moreover, we show that regions supporting individuation and identification vary across distinct stages of information processing. Our findings challenge influential models of multiple-object encoding in VSTM, which argue that individuation and identification are underpinned by a limited set of nonoverlapping brain regions.
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Midcingulate Motor Map and Feedback Detection: Converging Data from Humans and Monkeys
The functional and anatomical organization of the cingulate cortex across primate species is the subject of considerable and often confusing debate. The functions attributed to the midcingulate cortex (MCC) embrace, among others, feedback processing, pain, salience, action-reward association, premotor functions, and conflict monitoring. This multiplicity of functional concepts suggests either unresolved separation of functional contributions or integration and convergence. We here provide evidence from recent experiments in humans and from a meta-analysis of monkey data that MCC feedback-related activity is generated in the rostral cingulate premotor area by specific body maps directly related to the modality of feedback. As such, we argue for an embodied mechanism for adaptation and exploration in MCC. We propose arguments and precise tools to resolve the origins of performance monitoring signals in the medial frontal cortex, and to progress on issues regarding homology between human and nonhuman primate cingulate cortex.
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The Contextual Association Network Activates More for Remembered than for Imagined Events
The human capacities to remember events from the past and imagine events in the future rely on highly overlapping neural substrates. Neuroimaging studies have revealed brain regions that are more active for imagined events than remembered events, but the reverse pattern has not been shown consistently. Given that remembered events tend to be associated with more contextual information ( Johnson et al. 1988), one might expect a set of regions to demonstrate greater activity for remembered events. Specifically, regions sensitive to the strength of contextual associations might be hypothesized to show greater activity for remembered events. The present experiment tests this hypothesis. fMRI was used to identify brain regions within the contextual association network ( Bar and Aminoff 2003); regions within this network were then examined to see whether they showed differential activity during remembering and imagining. Bilateral regions within the parahippocampal cortex and retrosplenial complex responded more strongly to remembered past events, supporting work that suggests these events have more contextual information associated with them. Follow-up voxel-wise analysis demonstrated the specificity of these results, as did re-analysis of previous experimental datasets. These results suggest that a key differentiating feature of remembering and imagining is the strength of contextual associations.
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Lying and the Subsequent Desire for Toothpaste: Activity in the Somatosensory Cortex Predicts Embodiment of the Moral-Purity Metaphor
It is well known from literature and religious ceremonies that there is a link between physical cleansing and moral transgressions. Only recently, psychological experiments explored this association and demonstrated that a threat to moral purity increases the demand of physical cleansing. Moreover, it has been shown that physical cleansing is actually efficacious to cope with threatened morality. This so-called Macbeth effect has been explained by an embodiment of the moral-purity metaphor. We tested this hypothesis by means of an functional magnetic resonsce imaging (fMRI) experiment. Participants were instructed to enact scenarios including either an immoral act (lying) or a moral deed (telling the truth). Subsequently, the participants were asked to rate the desirableness of various products. Results revealed that participants rated cleansing products (but not other goods) more desirable after performing an immoral than after a moral act. This Macbeth effect was accompanied by an active cortical network including sensorimotor brain areas during rating of cleansing products (but not while evaluating noncleansing goods). The results demonstrate neurobiological evidence for an embodiment of the moral-purity metaphor. Thus, abstract thoughts about morality can be grounded in sensory experiences.
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Bodies are Represented as Wholes Rather Than Their Sum of Parts in the Occipital-Temporal Cortex
Behavioral studies suggested that bodies are represented as wholes rather than in a part-based manner. However, neural selectivity for body stimuli is found for both whole bodies and body parts. It is therefore undetermined whether the neural representation of bodies is configural or part-based. We used functional MRI to test the role of first-order configuration on body representation in the human occipital-temporal cortex by comparing the response to a whole body versus the sum of its parts. Results show that body-selective areas, whether defined by selectivity to headless bodies or body parts, preferred whole bodies over their sum of parts and successfully decoded body configuration. This configural representation was specific to body stimuli and not found for faces. In contrast, general object areas showed no preference for wholes over parts and decoded the configuration of both bodies and faces. Finally, whereas effects of inversion on configural face representation were specific to face-selective mechanisms, effects of body inversion were not unique to body-selective mechanisms. We conclude that the neural representation of body parts is strengthened by their arrangement into an intact body, thereby demonstrating a central role of first-order configuration in the neural representation of bodies in their category-selective areas.
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Brain Circuitry Supporting Multi-Organ Autonomic Outflow in Response to Nausea
While autonomic outflow is an important co-factor of nausea physiology, central control of this outflow is poorly understood. We evaluated sympathetic (skin conductance level) and cardiovagal (high-frequency heart rate variability) modulation, collected synchronously with functional MRI (fMRI) data during nauseogenic visual stimulation aimed to induce vection in susceptible individuals. Autonomic data guided analysis of neuroimaging data, using a stimulus-based (analysis windows set by visual stimulation protocol) and percept-based (windows set by subjects' ratings) approach. Increased sympathetic and decreased parasympathetic modulation was associated with robust and anti-correlated brain activity in response to nausea. Specifically, greater autonomic response was associated with reduced fMRI signal in brain regions such as the insula, suggesting an inhibitory relationship with premotor brainstem nuclei. Interestingly, some sympathetic/parasympathetic specificity was noted. Activity in default mode network and visual motion areas was anti-correlated with parasympathetic outflow at peak nausea. In contrast, lateral prefrontal cortical activity was anti-correlated with sympathetic outflow during recovery, soon after cessation of nauseogenic stimulation. These results suggest divergent central autonomic control for sympathetic and parasympathetic response to nausea. Autonomic outflow and the central autonomic network underlying ANS response to nausea may be an important determinant of overall nausea intensity and, ultimately, a potential therapeutic target.
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Fulminant hepatitis B as a result of reactivation in hematologic patient after rituximab therapy
Abstract
With great interest, we read the recent article by Cho et al. (Cho et al. 2015). regarding the high titers of anti-HBs prevent rituximab-related viral reactivation in resolved hepatitis B patient with non-Hodgkin's lymphoma. The authors very clearly determined the predictive factors for rituximab-related HBV reactivation in resolved hepatitis B patients, defined as HBsAg-negative, anti-HBc-positive, and undetectable HBV DNA. This article is protected by copyright. All rights reserved
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Dominant enrichment of phenotypically activated CD38+HLA-DR+CD8+ T cells, rather than CD38+HLA-DR+CD4+ T cells, in HIV/HCV coinfected patients on antiretroviral therapy
Abstract
Background
HIV infection may enhance immune-activation, while little is known regarding the role of HCV infection. This study investigates the impact of HCV in HIV coinfected patients with undetectable viraemia under HAART on the levels of peripheral T cell's immune-activation.
Methods
We determined T lymphocytes subsets to characterize immune-activation defined as CD38 and/or HLA-DR expression in chronic monoinfected HCV, HIV, and HIV/HCV coinfected subjects. 156 patients were divided into three groups: a) 77 HIV+ patients; b) 50 HCV+ patients; c) 29 coinfected HIV/HCV patients.
Results
The level of CD4+ was significantly higher in HCV+ than in HIV+ or in coinfected HIV/HCV subjects. The frequencies of CD4+CD38+/HLA-DR-, CD4+CD38-/HLA-DR+ and CD4+CD38+/HLA-DR+ in HIV+ patients were comparable to those measured in coinfected patients, but statistically higher than those observed in HCV+ subjects. The percentage of CD8+ was comparable in HIV-1+ patients and coinfected HIV/HCV but the results obtained in both groups were significantly higher compared to the results obtained in HCV patients. The level of CD8+CD38+/HLA-DR- showed values lower in HIV+ patients than in that monoinfected HCV and coinfected HIV/HCV patients. The frequencies of CD8+CD38-/HLA-DR+ were higher in HIV+ patients compared to HCV+ and coinfected HIV/HCV patients. HIV/HCV coinfected group showed highest levels of CD8+CD38+/HLA-DR+.
Conclusions
HIV plays a pivotal role to determine the immune activation in the host. The role of HCV needs of further investigations but our data show that HCV mainly influences the immune-activation of the pool of CD8, but also probably plays a supporting additive effect on CD4 immune-activation. This article is protected by copyright. All rights reserved
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Nanopillar films with polyoxometalate-doped polyaniline for electrochemical detection of hydrogen peroxide
DOI: 10.1039/C5AN02134K, Paper
An enzymeless electrochemical sensor was developed for detection of hydrogen peroxide based on the use of highly ordered polyoxometalate-doped polyaniline nanopillar arrays.
To cite this article before page numbers are assigned, use the DOI form of citation above.
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Genetically Anchored Fluorescent Probes for Subcellular Specific Imaging of Hydrogen Sulfide
DOI: 10.1039/C5AN02497H, Communication
Imaging hydrogen sulfide (H2S) at the subcellular resolution will greatly improve the understanding of functions of this signaling molecule. Taking advantage of the protein labeling technologies, we report a general...
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Parents of terror victims. A longitudinal study of parental mental health following the 2011 terrorist attack on Utøya Island
Publication date: Available online 13 January 2016
Source:Journal of Anxiety Disorders
Author(s): Siri Thoresen, Tine K. Jensen, Tore Wentzel-Larsen, Grete Dyb
Background and aimsLittle is known about parents' health following their children's exposure to trauma. We investigated the mental health of parents of young terrorist survivors and assessed parental distress and guilt as potential predictors of mental health.MethodMothers and fathers (N=531) participated in two study waves 4–5 and 14–15 months after the shooting. Posttraumatic stress reactions (PTSS) and anxiety/depression were compared with age- and gender-adjusted expected scores that were calculated from a concurrent population study. Mixed effects models investigated the associations between parental distress, parental guilt, and mental health.ResultsParents' level of anxiety/depression was three times higher and PTSS was five times higher than that of the general population. Parental distress and guilt about their child's traumatic experience contributed uniquely to symptoms at both time points.ConclusionsParents of traumatized youth constitute a vulnerable group that has been overlooked in the literature. Intervention strategies following trauma should include both survivors and their parents.
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Data supporting the regulation of FOXC2 in podocyte dysfunction
Publication date: March 2016
Source:Data in Brief, Volume 6
Author(s): Neeta Datta, Sonja Lindfors, Naoyuki Miura, Moin A. Saleem, Sanna Lehtonen
This data article shows the expression levels of specific podocyte injury markers and podocyte slit diaphragm protein nephrin in obese and lean Zucker rat glomeruli. It also contains information on the effect of the overexpression of transcription factor FOXC2 on the ratio of F- and G-actin and the expression level of ZO-1 in differentiated human podocytes. The article also shows data on the effect of treatments of differentiated podocytes with various factors associated with obesity and diabetes on the expression level of FOXC2. The detailed interpretation of these data and other aspects of podocyte injury mediated by upregulation of FOXC2 can be found in "Overexpression of transcription factor FOXC2 in cultured human podocytes upregulates injury markers and increases motility [1].
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Correction: Testing and validating electroanalytical simulations
DOI: 10.1039/C6AN90007K, Correction
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Ascorbic acid supplementation improves skeletal muscle oxidative stress and insulin sensitivity in people with type 2 diabetes: Findings of a randomized controlled study
Publication date: Available online 13 January 2016
Source:Free Radical Biology and Medicine
Author(s): Shaun A. Mason, Paul A. Della Gatta, Rod J. Snow, Aaron P. Russell, Glenn D. Wadley
Aim/hypothesisSkeletal muscle insulin resistance and oxidative stress are characteristic metabolic disturbances in people with type 2 diabetes. Studies in insulin resistant rodents show an improvement in skeletal muscle insulin sensitivity and oxidative stress following antioxidant supplementation. We therefore investigated the potential ameliorative effects of antioxidant ascorbic acid (AA) supplementation on skeletal muscle insulin sensitivity and oxidative stress in people with type 2 diabetes.MethodsParticipants with stable glucose control commenced a randomized cross-over study involving four months of AA (2×500mg/day) or placebo supplementation. Insulin sensitivity was assessed using a hyperinsulinaemic, euglycaemic clamp coupled with infusion of 6,6-D2 glucose. Muscle biopsies were measured for AA concentration and oxidative stress markers that included basal measures (2′,7′-dichlorofluorescin [DCFH] oxidation, ratio of reduced-to-oxidized glutathione [GSH/GSSG] and F2-Isoprostanes) and insulin-stimulated measures (DCFH oxidation). Antioxidant concentrations, citrate synthase activity and protein abundances of sodium-dependent vitamin C transporter 2 (SVCT2), total Akt and phosphorylated Akt (ser473) were also measured in muscle samples.ResultsAA supplementation significantly increased insulin-mediated glucose disposal (delta rate of glucose disappearance; ∆Rd) (p=0.009), peripheral insulin-sensitivity index (p=0.046), skeletal muscle AA concentration (p=0.017) and muscle SVCT2 protein expression (p=0.008); but significantly decreased skeletal muscle DCFH oxidation during hyperinsulinaemia (p=0.007) when compared with placebo. Total superoxide dismutase activity was also lower following AA supplementation when compared with placebo (p=0.006). Basal oxidative stress markers, citrate synthase activity, endogenous glucose production, HbA1C and muscle Akt expression were not significantly altered by AA supplementation.Conclusions/interpretationIn summary, oral AA supplementation ameliorates skeletal muscle oxidative stress during hyperinsulinaemia and improves insulin-mediated glucose disposal in people with type 2 diabetes. Findings implicate AA supplementation as a potentially inexpensive, convenient, and effective adjunct therapy in the treatment of insulin resistance in people with type 2 diabetes.
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Small molecules preventing GAPDH aggregation are therapeutically applicable in cell and rat models of oxidative stress
Publication date: March 2016
Source:Free Radical Biology and Medicine, Volume 92
Author(s): Vladimir F. Lazarev, Alina D. Nikotina, Pavel I. Semenyuk, Diana B. Evstafyeva, Elena R. Mikhaylova, Vladimir I. Muronetz, Maxim A. Shevtsov, Anastasia V. Tolkacheva, Anatoly V. Dobrodumov, Alexey L. Shavarda, Irina V. Guzhova, Boris A. Margulis
Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is one of the most abundant targets of the oxidative stress. Oxidation of the enzyme causes its inactivation and the formation of intermolecular disulfide bonds, and leads to the accumulation of GAPDH aggregates and ultimately to cell death. The aim of this work was to reveal the ability of chemicals to break the described above pathologic linkage by inhibiting GAPDH aggregation. Using the model of oxidative stress based on SK-N-SH human neuroblastoma cells treated with hydrogen peroxide, we found that lentivirus-mediated down- or up-regulation of GAPDH content caused inhibition or enhancement of the protein aggregation and respectively reduced or increased the level of cell death. To reveal substances that are able to inhibit GAPDH aggregation, we developed a special assay based on dot ultrafiltration using the collection of small molecules of plant origin. In the first round of screening, five compounds were found to possess anti-aggregation activity as established by ultrafiltration and dynamic light scattering; some of the substances efficiently inhibited GAPDH aggregation in nanomolar concentrations. The ability of the compounds to bind GAPDH molecules was proved by the drug affinity responsive target stability assay, molecular docking and differential scanning calorimetry. Results of experiments with SK-N-SH human neuroblastoma treated with hydrogen peroxide show that two substances, RX409 and RX426, lowered the degree of GAPDH aggregation and reduced cell death by 30%. Oxidative injury was emulated in vivo by injecting of malonic acid into the rat brain, and we showed that the treatment with RX409 or RX426 inhibited GAPDH-mediated aggregation in the brain, reduced areas of the injury as proved by magnetic resonance imaging, and augmented the behavioral status of the rats as established by the "beam walking" test. In conclusion, the data show that two GAPDH binders could be therapeutically relevant in the treatment of injuries stemming from hard oxidative stress.
Graphical abstract
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Oxidised LDL induced extracellular trap formation in human neutrophils via TLR-PKC-IRAK-MAPK and NADPH-oxidase activation
Publication date: Available online 14 January 2016
Source:Free Radical Biology and Medicine
Author(s): Deepika Awasthi, Sheela Nagarkoti, Amit Kumar, Megha Dubey, Abhishek Kumar Singh, Priya Pathak, Tulika Chandra, Manoj Kumar Barthwal, Madhu Dikshit
Neutrophil extracellular traps (NETs) formation was initially linked with host defence and extracellular killing of pathogens. However, recent studies have highlighted their inflammatory potential. Oxidized low density lipoprotein (oxLDL) has been implicated as an independent risk factor in various acute or chronic inflammatory diseases including systemic inflammatory response syndrome (SIRS). In the present study we investigated effect of oxLDL on NETs formation and elucidated the underlying signalling mechanism. Treatment of oxLDL to adhered PMNs led to a time and concentration dependent ROS generation and NETs formation. OxLDL induced free radical formation and NETs release were significantly prevented in presence of NADPH oxidase (NOX) inhibitors suggesting role of NOX activation in oxLDL induced NETs release. Blocking of both toll like receptor (TLR) -2 and 6 significantly reduced oxLDL induced NETs formation indicating requirement of both the receptors. We further identified Protein kinase C (PKC)-Interleukin-1 receptor associated kinase (IRAKs)-mitogen-activated protein kinase (MAPK) pathway as downstream intracellular signalling mediators involved in oxLDL induced NETs formation. OxLDL components such as oxidized phospholipids (lysophosphatidylcholine (LPC) and oxidized 1-palmitoyl-2-arachidonyl-sn- glycero-3-phosphorylcholine (oxPAPC)) were most potent NETs inducers and might be crucial for oxLDL mediating NETs release. Other components like, oxysterols, malondialdehyde (MDA) and 4-hydroxynonenal (4-HNE) were however less potent as compared to oxidized phospholipids. This study thus demonstrates for the first time that treatment of human PMNs with oxLDL or its various oxidized phopholipid component mediated NETs release, implying their role in the pathogenesis of inflammatory diseases such as SIRS.
Graphical abstract
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Continuous attractor network models of grid cell firing based on excitatory-inhibitory interactions
Abstract
Neurons in the medial entorhinal cortex encode location through spatial firing fields that have a grid-like organisation. The challenge of identifying mechanisms for grid firing has been addressed through experimental and theoretical investigations of medial entorhinal circuits. Here, we discuss evidence for continuous attractor network models that account for grid firing by synaptic interactions between excitatory and inhibitory cells. These models assume that grid-like firing patterns are the result of computation of location from velocity inputs, with additional spatial input required to oppose drift in the attractor state. We focus on properties of continuous attractor networks that are revealed by explicitly considering excitatory and inhibitory neurons, their connectivity and their membrane potential dynamics. Models at this level of detail can account for theta-nested gamma oscillations as well as grid firing, predict spatial firing of interneurons as well as excitatory cells, show how gamma oscillations can be modulated independently from spatial computations, reveal critical roles for neuronal noise, and demonstrate that only a subset of excitatory cells in a network need have grid-like firing fields. Evaluating experimental data against predictions from detailed network models will be important for establishing the mechanisms mediating grid firing.
This article is protected by copyright. All rights reserved
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Prevalence of occult hepatitis C virus infection in the Iranian patients with human immunodeficiency virus infection
Abstract
Occult hepatitis C virus infection is a new form of chronic HCV infection described by the presence of the genomic HCV-RNA in liver biopsy and/or PBMC samples, and undetectable levels or absence of HCV-RNA and in the absence or presence of anti HCV antibodies in the plasma specimens. The aim of the present study was to evaluate the occurrence of OCI among Iranian subjects infected with HIV using RT-nested PCR. From March 2014 until April 2015, 109 Iranian patients with established HIV infection were enrolled in this cross-sectional study. After extraction of viral RNA from the plasma and PBMC samples, HCV-RNA status was examined by RT–nested PCR using primers from the 5′-NTR. HCV genotyping was conducted using RFLP analysis. For the confirmation of HCV genotyping by RFLP method, the PCR products were sequenced. Of the 109 patients, 50 were positive for antibodies against HCV. The HCV-RNA was detected in PBMC specimens in 6 (10.2%) out of the total 59 patients negative for anti-HCV Abs and undetectable plasma HCV-RNA and also from 4 (8.0%) out of the total 50 patients positive for anti-HCV Abs and undetectable plasma HCV-RNA. HCV genotyping analysis showed that 6 (60.0%) patients were infected with HCV subtype 3a, 3 (30.0%) were infected with HCV subtype 1a and 1 (10.0%) patient was infected with HCV subtype 1b. This study revealed the incidence of OCI (9.2%) in HIV-infected Iranian patients. Hence, designing prospective studies focusing on the detection of OCI in these patients would provide more information. This article is protected by copyright. All rights reserved
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The Function of Naringin in Inducing Secretion of Osteoprotegerin and Inhibiting Formation of Osteoclasts
Osteoporosis has become one of the most prevalent and costly diseases in the world. It is a metabolic disease characterized by reduction in bone mass due to an imbalance between bone formation and resorption. Osteoporosis causes fractures, prolongs bone healing, and impedes osseointegration of dental implants. Its pathological features include osteopenia, degradation of bone tissue microstructure, and increase of bone fragility. In traditional Chinese medicine, the herb Rhizoma Drynariae has been commonly used to treat osteoporosis and bone nonunion. However, the precise underlying mechanism is as yet unclear. Osteoprotegerin is a cytokine receptor shown to play an important role in osteoblast differentiation and bone formation. Hence, activators and ligands of osteoprotegerin are promising drug targets and have been the focus of studies on the development of therapeutics against osteoporosis. In the current study, we found that naringin could synergistically enhance the action of 1α,25-dihydroxyvitamin D3 in promoting the secretion of osteoprotegerin by osteoblasts in vitro. In addition, naringin can also influence the generation of osteoclasts and subsequently bone loss during organ culture. In conclusion, this study provides evidence that natural compounds such as naringin have the potential to be used as alternative medicines for the prevention and treatment of osteolysis.
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IJMS, Vol. 17, Pages 90: Function and Regulation of Heterotrimeric G Proteins during Chemotaxis
Chemotaxis, or directional movement towards an extracellular gradient of chemicals, is necessary for processes as diverse as finding nutrients, the immune response, metastasis and wound healing. Activation of G-protein coupled receptors (GPCRs) is at the very base of the chemotactic signaling pathway. Chemotaxis starts with binding of the chemoattractant to GPCRs at the cell-surface, which finally leads to major changes in the cytoskeleton and directional cell movement towards the chemoattractant. Many chemotaxis pathways that are directly regulated by Gβγ have been identified and studied extensively; however, whether Gα is just a handle that regulates the release of Gβγ or whether Gα has its own set of distinct chemotactic effectors, is only beginning to be understood. In this review, we will discuss the different levels of regulation in GPCR signaling and the downstream pathways that are essential for proper chemotaxis.
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IJMS, Vol. 17, Pages 105: Urine Aquaporin-2: A Promising Marker of Response to the Arginine Vasopressin Type-2 Antagonist, Tolvaptan in Patients with Congestive Heart Failure
Aquaporin-2, a member of the aquaporin family, is an arginine vasopressin-regulated water channel expressed in the renal collecting duct, and a promising marker of the concentrating and diluting ability of the kidney. The arginine vasopressin type-2 antagonist, tolvaptan, is a new-generation diuretic; it is especially indicated in patients with decompensated heart failure refractory to conventional diuretics. However, the ideal responders to tolvaptan have not yet been identified, and non-responders experience worse clinical courses despite treatment with tolvaptan. Urine aquaporin-2 has recently been demonstrated as a promising predictor of response to tolvaptan. We here validated aquaporin-2-guided tolvaptan therapy in patients with decompensated heart failure. Long-term efficacy of tolvaptan treatment in the responders defined by aquaporin-2 needs to be validated in the future prospective study.
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IJMS, Vol. 17, Pages 102: Cellular Pathways in Response to Ionizing Radiation and Their Targetability for Tumor Radiosensitization
During the last few decades, improvements in the planning and application of radiotherapy in combination with surgery and chemotherapy resulted in increased survival rates of tumor patients. However, the success of radiotherapy is impaired by two reasons: firstly, the radioresistance of tumor cells and, secondly, the radiation-induced damage of normal tissue cells located in the field of ionizing radiation. These limitations demand the development of drugs for either radiosensitization of tumor cells or radioprotection of normal tissue cells. In order to identify potential targets, a detailed understanding of the cellular pathways involved in radiation response is an absolute requirement. This review describes the most important pathways of radioresponse and several key target proteins for radiosensitization.
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IJMS, Vol. 17, Pages 103: Free Radical Scavenging and Cellular Antioxidant Properties of Astaxanthin
Astaxanthin is a coloring agent which is used as a feed additive in aquaculture nutrition. Recently, potential health benefits of astaxanthin have been discussed which may be partly related to its free radical scavenging and antioxidant properties. Our electron spin resonance (ESR) and spin trapping data suggest that synthetic astaxanthin is a potent free radical scavenger in terms of diphenylpicryl-hydrazyl (DPPH) and galvinoxyl free radicals. Furthermore, astaxanthin dose-dependently quenched singlet oxygen as determined by photon counting. In addition to free radical scavenging and singlet oxygen quenching properties, astaxanthin induced the antioxidant enzyme paroxoanase-1, enhanced glutathione concentrations and prevented lipid peroxidation in cultured hepatocytes. Present results suggest that, beyond its coloring properties, synthetic astaxanthin exhibits free radical scavenging, singlet oxygen quenching, and antioxidant activities which could probably positively affect animal and human health.
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IJMS, Vol. 17, Pages 104: Fourier Transform Mass Spectrometry: The Transformation of Modern Environmental Analyses
Unknown compounds in environmental samples are difficult to identify using standard mass spectrometric methods. Fourier transform mass spectrometry (FTMS) has revolutionized how environmental analyses are performed. With its unsurpassed mass accuracy, high resolution and sensitivity, researchers now have a tool for difficult and complex environmental analyses. Two features of FTMS are responsible for changing the face of how complex analyses are accomplished. First is the ability to quickly and with high mass accuracy determine the presence of unknown chemical residues in samples. For years, the field has been limited by mass spectrometric methods that were based on knowing what compounds of interest were. Secondly, by utilizing the high resolution capabilities coupled with the low detection limits of FTMS, analysts also could dilute the sample sufficiently to minimize the ionization changes from varied matrices.
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IJMS, Vol. 17, Pages 100: Iron in Multiple Sclerosis and Its Noninvasive Imaging with Quantitative Susceptibility Mapping
Iron is considered to play a key role in the development and progression of Multiple Sclerosis (MS). In particular, iron that accumulates in myeloid cells after the blood-brain barrier (BBB) seals may contribute to chronic inflammation, oxidative stress and eventually neurodegeneration. Magnetic resonance imaging (MRI) is a well-established tool for the non-invasive study of MS. In recent years, an advanced MRI method, quantitative susceptibility mapping (QSM), has made it possible to study brain iron through in vivo imaging. Moreover, immunohistochemical investigations have helped defining the lesional and cellular distribution of iron in MS brain tissue. Imaging studies in MS patients and of brain tissue combined with histological studies have provided important insights into the role of iron in inflammation and neurodegeneration in MS.
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IJMS, Vol. 17, Pages 107: Erdr1 Suppresses Murine Melanoma Growth via Regulation of Apoptosis
Melanoma, one of the aggressive cancers, is known to be resistant to chemotherapy. Because of its aggressive nature, effectively inducing apoptosis is necessary to treat melanoma. Erythroid differentiation regulator 1 (Erdr1) is known to be a stress-related survival factor exhibiting anti-cancer effects in several cancers. However, little is known about the functions and underlying mechanisms of Erdr1 so far. To demonstrate the effect of Erdr1 in melanoma apoptosis, recombinant murine Erdr1 was injected into mice implanted with B16F10 melanoma cells. In vivo tumor growth was significantly inhibited in mice injected with Erdr1 compared to the control. In addition, the tumor from Erdr1-injected mice showed an increased level of apoptosis. Accordingly, apoptosis-regulating factors including anti-apoptotic marker Bcl-2 and pro-apoptotic marker Bax in the tumor tissues were examined. As expected, the decreased level of Bcl-2 and increased level of Bax were detected in tumors within the mice injected with Erdr1. Based on the in vivo study, the role of Erdr1 in tumor apoptosis was further tested by incubating it with cells of the murine melanoma cell line B16F10. Erdr1-induced apoptosis in B16F10 cells was observed. Additionally, Erdr1 downregulated STAT3 activity, inhibiting apoptosis via regulation of the Bcl-2 family. Overall, data demonstrate that Erdr1 induced murine melanoma apoptosis through the regulation of Bcl-2 and Bax. These findings suggest that Erdr1 is a novel regulator of apoptosis in melanoma.
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Marine Drugs, Vol. 14, Pages 16: Marine Isonitriles and Their Related Compounds
Marine isonitriles represent the largest group of natural products carrying the remarkable isocyanide moiety. Together with marine isothiocyanates and formamides, which originate from the same biosynthetic pathways, they offer diverse biological activities and in spite of their exotic nature they may constitute potential lead structures for pharmaceutical development. Among other biological activities, several marine isonitriles show antimalarial, antitubercular, antifouling and antiplasmodial effects. In contrast to terrestrial isonitriles, which are mostly derived from α-amino acids, the vast majority of marine representatives are of terpenoid origin. An overview of all known marine isonitriles and their congeners will be given and their biological and chemical aspects will be discussed.
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A 70% Ethanol Extract of Mistletoe Rich in Betulin, Betulinic Acid, and Oleanolic Acid Potentiated β-Cell Function and Mass and Enhanced Hepatic Insulin Sensitivity
We investigated that the long-term consumption of the water (KME-W) and 70% ethanol (KME-E) mistletoe extracts had antidiabetic activities in partial pancreatectomized (Px) rats. Px rats were provided with a high-fat diet containing 0.6% KME-E, 0.6% KME-W, and 0.6% dextrin (control) for 8 weeks. As normal-control, Sham-operated rats were provided with 0.6% dextrin. In cell-based studies, the effects of its main terpenoids (betulin, betulinic acid, and oleanolic acid) on glucose metabolism were measured. Both KME-W and KME-E decreased epididymal fat mass by increasing fat oxidation in diabetic rats. KME-E but not KME-W exhibited greater potentiation of first-phase insulin secretion than the Px-control in a hyperglycemic clamp. KME-E also made β-cell mass greater than the control by increasing β-cell proliferation and decreasing its apoptosis. In a euglycemic-hyperinsulinemic clamp, whole-body glucose infusion rate and hepatic glucose output increased with potentiating hepatic insulin signaling in the following order: Px-control, KME-W, KME-E, and normal-control. Betulin potentiated insulin-stimulated glucose uptake via increased PPAR-γ activity and insulin signaling in 3T3-L1 adipocytes, whereas oleanolic acid enhanced glucose-stimulated insulin secretion and cell proliferation in insulinoma cells. In conclusion, KME-E prevented the deterioration of glucose metabolism in diabetic rats more effectively than KME-W and KME-E can be a better therapeutic agent for type 2 diabetes than KME-W.
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Materials, Vol. 9, Pages 47: Surface Functional Poly(lactic Acid) Electrospun Nanofibers for Biosensor Applications
In this work, biotin surface functionalized hydrophilic non-water-soluble biocompatible poly(lactic acid) (PLA) nanofibers are created for their potential use as biosensors. Varying concentrations of biotin (up to 18 weight total percent (wt %)) were incorporated into PLA fibers together with poly(lactic acid)-block-poly(ethylene glycol) (PLA-b-PEG) block polymers. While biotin provided surface functionalization, PLA-b-PEG provided hydrophilicity to the final fibers. Morphology and surface-available biotin of the final fibers were studied by Field Emission Scanning Electron Microscopy (FESEM) and competitive colorimetric assays. The incorporation of PLA-b-PEG block copolymers not only decreased fiber diameters but also dramatically increased the amount of biotin available at the fiber surface able to bind avidin. Finally, fiber water stability tests revealed that both biotin and PLA-b-PEG, migrated to the aqueous phase after relatively extended periods of water exposure. The functional hydrophilic nanofiber created in this work shows a potential application as a biosensor for point-of-care diagnostics.
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Energies, Vol. 9, Pages 43: Reliability Analysis and Overload Capability Assessment of Oil-Immersed Power Transformers
Smart grids have been constructed so as to guarantee the security and stability of the power grid in recent years. Power transformers are a most vital component in the complicated smart grid network. Any transformer failure can cause damage of the whole power system, within which the failures caused by overloading cannot be ignored. This research gives a new insight into overload capability assessment of transformers. The hot-spot temperature of the winding is the most critical factor in measuring the overload capacity of power transformers. Thus, the hot-spot temperature is calculated to obtain the duration running time of the power transformers under overloading conditions. Then the overloading probability is fitted with the mature and widely accepted Weibull probability density function. To guarantee the accuracy of this fitting, a new objective function is proposed to obtain the desired parameters in the Weibull distributions. In addition, ten different mutation scenarios are adopted in the differential evolutionary algorithm to optimize the parameter in the Weibull distribution. The final comprehensive overload capability of the power transformer is assessed by the duration running time as well as the overloading probability. Compared with the previous studies that take no account of the overloading probability, the assessment results obtained in this research are much more reliable.
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Nutrients, Vol. 8, Pages 45: Effect of Polydextrose on Subjective Feelings of Appetite during the Satiation and Satiety Periods: A Systematic Review and Meta-Analysis
Introduction: Subjective feelings of appetite are measured using visual analogue scales (VAS) in controlled trials. However, the methods used to analyze VAS during the Satiation (pre- to post-meal) and Satiety (post-meal to subsequent meal) periods vary broadly, making it difficult to compare results amongst independent studies testing the same product. This review proposes a methodology to analyze VAS during both the Satiation and Satiety periods, allowing us to compare results in a meta-analysis. Methods: A methodology to express VAS results as incremental areas under the curve (iAUC) for both the Satiation and Satiety periods is proposed using polydextrose as a case study. Further, a systematic review and meta-analysis on subjective feelings of appetite was conducted following the PRISMA methodology. Meta-analyses were expressed as Standardized Mean Difference (SMD). Results: Seven studies were included in the meta-analysis. There were important differences in the methods used to analyze appetite ratings amongst these studies. The separate subjective feelings of appetite reported were Hunger, Satisfaction, Fullness, Prospective Food Consumption, and the Desire to Eat. The method proposed here allowed the results of the different studies to be homogenized. The meta-analysis showed that Desire to Eat during the Satiation period favors polydextrose for the reduction of this subjective feeling of appetite (SMD = 0.24, I2 < 0.01, p = 0.018); this effect was also significant in the sub-analysis by sex for the male population (SMD = 0.35, I2 < 0.01, p = 0.015). There were no other significant results. Conclusion: It is possible to compare VAS results from separate studies. The assessment of iAUC for both the Satiation and Satiety periods generates results of homogeneous magnitudes. This case study demonstrates, for the first time, that polydextrose reduces the Desire to Eat during the Satiation period. This may explain, at least in part, the observed effects of polydextrose on the reduction of levels of energy intake at subsequent meals.
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Antibiotics, Vol. 5, Pages 6: Controversies in Antimicrobial Stewardship: Focus on New Rapid Diagnostic Technologies and Antimicrobials
Antimicrobial stewardship programs (ASPs) are challenged with ensuring appropriate antimicrobial use while minimizing expenditures. ASPs have consistently demonstrated improved patient outcomes and significant cost reductions but are continually required to justify the costs of their existence and interventions due to the silo mentality often adopted by hospital administrators. As new technologies and antimicrobials emerge, ASPs are in a constant tug-of-war between providing optimal clinical outcomes and ensuring cost containment. Additionally, robust data on cost-effectiveness of new rapid diagnostic technologies and antimicrobials with subsequent ASP interventions to provide justification are lacking. As the implementation of an ASP will soon be mandatory for acute care hospitals in the United States, ASPs must find ways to justify novel interventions to align themselves with healthcare administrators. This review provides a framework for the justification of implementing a rapid diagnostic test or adding a new antimicrobial to formulary with ASP intervention, reviews approaches to demonstrating cost-effectiveness, and proposes methods for which ASPs may reduce healthcare expenditures via alternative tactics.
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Viruses, Vol. 8, Pages 21: Advances and Challenges in Studying Hepatitis B Virus In Vitro
Hepatitis B virus (HBV) is a small DNA virus that infects the liver. Current anti-HBV drugs efficiently suppress viral replication but do not eradicate the virus due to the persistence of its episomal DNA. Efforts to develop reliable in vitro systems to model HBV infection, an imperative tool for studying HBV biology and its interactions with the host, have been hampered by major limitations at the level of the virus, the host and infection readouts. This review summarizes major milestones in the development of in vitro systems to study HBV. Recent advances in our understanding of HBV biology, such as the discovery of the bile-acid pump sodium-taurocholate cotransporting polypeptide (NTCP) as a receptor for HBV, enabled the establishment of NTCP expressing hepatoma cell lines permissive for HBV infection. Furthermore, advanced tissue engineering techniques facilitate now the establishment of HBV infection systems based on primary human hepatocytes that maintain their phenotype and permissiveness for infection over time. The ability to differentiate inducible pluripotent stem cells into hepatocyte-like cells opens the door for studying HBV in a more isogenic background, as well. Thus, the recent advances in in vitro models for HBV infection holds promise for a better understanding of virus-host interactions and for future development of more definitive anti-viral drugs.
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Applied Sciences, Vol. 6, Pages 18: Fault-Tolerant Visual Secret Sharing Schemes without Pixel Expansion
Visual cryptography encrypts a secret image into two meaningless random images, called shares, such that it can be decrypted by human vision without any calculations. However, there would be problems in alignment when these two shares are staked by hand in practice. Therefore, this paper presents the fault-tolerant schemes of stacking two shares that are acquired from secret image encryption without pixel expansion. The main idea of these schemes is to combine several pixels as a unit and then to encrypt each unit into a specific combination of pixels. Both theoretical analysis and simulation results demonstrate the effectiveness and practicality of the proposed schemes.
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Materials, Vol. 9, Pages 48: Synthesis, X-ray Structure, Optical, and Electrochemical Properties of a White-Light-Emitting Molecule
A new white-light-emitting molecule (1) was synthesized and characterized by NMR spectroscopy, high resolution mass spectrometry, and single-crystal X-ray diffraction. Compound 1 crystallizes in the orthorhombic space group Pnma, with a = 12.6814(6), b = 7.0824(4), c = 17.4628(9) Å, α = 90°, β = 90°, γ = 90°. In the crystal, molecules are linked by weak intermolecular C-H···O hydrogen bonds, forming an infinite chain along [100], generating a C(10) motif. Compound 1 possesses an intramolecular six-membered-ring hydrogen bond, from which excited-state intramolecular proton transfer (ESIPT) takes place from the phenolic proton to the carbonyl oxygen, resulting in a tautomer that is in equilibrium with the normal species, exhibiting a dual emission that covers almost all of the visible spectrum and consequently generates white light. It exhibits one irreversible one-electron oxidation and two irreversible one-electron reductions in dichloromethane at modest potentials. Furthermore, the geometric structures, frontier molecular orbitals (MOs), and the potential energy curves (PECs) for 1 in the ground and the first singlet excited state were fully rationalized by density functional theory (DFT) and time-dependent DFT calculations. The results demonstrate that the forward and backward ESIPT may happen on a similar timescale, enabling the excited-state equilibrium to be established.
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Antioxidants, Vol. 5, Pages 3: Hydrogen Sulfide, Oxidative Stress and Periodontal Diseases: A Concise Review
In the past years, biomedical research has recognized hydrogen sulfide (H2S) not only as an environmental pollutant but also, along with nitric oxide and carbon monoxide, as an important biological gastransmitter with paramount roles in health and disease. Current research focuses on several aspects of H2S biology such as the biochemical pathways that generate the compound and its functions in human pathology or drug synthesis that block or stimulate its biosynthesis. The present work addresses the knowledge we have to date on H2S production and its biological roles in the general human environment with a special focus on the oral cavity and its involvement in the initiation and development of periodontal diseases.
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Healthcare, Vol. 4, Pages 10: Developing a Complex Educational–Behavioural Intervention: The TREAT Intervention for Patients with Atrial Fibrillation
This article describes the theoretical and pragmatic development of a patient-centred intervention for patients with atrial fibrillation (AF). Theoretical models (Common Sense Model, Necessity-Concerns Framework), clinical frameworks, and AF patient feedback contributed to the design of a one-off hour-long behaviour-change intervention package. Intervention materials consisted of a DVD, educational booklet, diary and worksheet, which were patient-centred and easy to administer. The intervention was evaluated within a randomised controlled trial. Several "active theoretical ingredients" were identified (for e.g., where patients believed their medication was less harmful they spent more time within the therapeutic range (TTR), with general harm scores predicting TTR at 6 months). Allowing for social comparison and adopting behaviour change techniques enabled accurate patient understanding of their condition and medication. The process of developing the intervention using theory-derived content and evaluation tools allowed a greater understanding of the mechanisms by which this intervention was successful. Alleviating concerns about treatment medication by educating patients can help to improve adherence. This process of intervention development could be adopted for a range of chronic illnesses and treatments. Critical elements should include the use of: (1) clinical guidelines; (2) appropriate theoretical models; (3) patient input; and (4) appropriate evaluation tools.
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Gels, Vol. 2, Pages 3: Synthesis and Characterization of New Functional Photo Cross-Linkable Smart Polymers Containing Vanillin Derivatives
The synthesis of new functional monomers based on vanillin is reported. The monomers further were used in the synthesis of different temperature-responsive photo cross-linkable polymers via free radical polymerization with N-isopropyl acrylamide and a maleimide photo cross-linker. These polymers were characterized by NMR, FTIR and UV spectroscopy, as well as gel permeation chromatography (GPC) and differential scanning calorimetry (DSC). Critical solution temperatures were determined by UV spectroscopy. Hydrogel thin films were formed by spin coating of a polymer solution over gold with adhesion promotor followed by cross-linking by UV irradiation. The swelling properties were determined by surface plasmon resonance coupled with optical waveguide spectroscopy. The swelling behavior of the hydrogel films was determined as a function of temperature. The incorporation of a dialkyl amino group compensated the hydrophobic effect of the vanillin monomer. Transition temperatures in the physiological range could be obtained.
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JCM, Vol. 5, Pages 8: MicroRNA Regulation of Epithelial to Mesenchymal Transition
Epithelial to mesenchymal transition (EMT) is a central regulatory program that is similar in many aspects to several steps of embryonic morphogenesis. In addition to its physiological role in tissue repair and wound healing, EMT contributes to chemo resistance, metastatic dissemination and fibrosis, amongst others. Classically, the morphological change from epithelial to mesenchymal phenotype is characterized by the appearance or loss of a group of proteins which have come to be recognized as markers of the EMT process. As with all proteins, these molecules are controlled at the transcriptional and translational level by transcription factors and microRNAs, respectively. A group of developmental transcription factors form the backbone of the EMT cascade and a large body of evidence shows that microRNAs are heavily involved in the successful coordination of mesenchymal transformation and vice versa, either by suppressing the expression of different groups of transcription factors, or otherwise acting as their functional mediators in orchestrating EMT. This article dissects the contribution of microRNAs to EMT and analyzes the molecular basis for their roles in this cellular process. Here, we emphasize their interaction with core transcription factors like the zinc finger enhancer (E)-box binding homeobox (ZEB), Snail and Twist families as well as some pluripotency transcription factors.
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Coatings, Vol. 6, Pages 3: On Modulating Interfacial Structure towards Improved Anti-Icing Performance
The design of anti-icing surfaces presents an interface with high causal density that has been challenging to quantify in terms of individual contributions of various interactions and environmental factors. In this commentary, we highlight the role of interfacial water structure as uniquely expressing the physico-chemical aspects of ice accretion. Recent work on the topic that focuses on control of interfacial structure is discussed along with results by our research group on wettability of chemically modified surfaces and the role of ions in modulating interfacial structure. Suggestions for systematic studies to understand the fundamental interactions at play in ice adhesion at interfaces are made especially in the under-explored areas of cooperative hydrogen bonding and the role of solvated counterions. Insights expected from such studies would contribute to design of robust anti-icing hierarchies.
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IJERPH, Vol. 13, Pages 129: Behavior Change without Behavior Change Communication: Nudging Handwashing among Primary School Students in Bangladesh
Behavior change communication for improving handwashing with soap can be labor and resource intensive, yet quality results are difficult to achieve. Nudges are environmental cues engaging unconscious decision-making processes to prompt behavior change. In this proof-of-concept study, we developed an inexpensive set of nudges to encourage handwashing with soap after toilet use in two primary schools in rural Bangladesh. We completed direct observation of behaviors at baseline, after providing traditional handwashing infrastructure, and at multiple time periods following targeted handwashing nudges (1 day, 2 weeks, and 6 weeks). No additional handwashing education or motivational messages were completed. Handwashing with soap among school children was low at baseline (4%), increasing to 68% the day after nudges were completed and 74% at both 2 weeks and 6 weeks post intervention. Results indicate that nudge-based interventions have the potential to improve handwashing with soap among school-aged children in Bangladesh and specific areas of further inquiry are discussed.
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Remote Sensing, Vol. 8, Pages 64: Correction: Pimont, F. et al. Estimating Leaf Bulk Density Distribution in a Tree Canopy Using Terrestrial LiDAR and a Straightforward Calibration Procedure. Remote Sens. 2015, 7(6), 7995-8018
After publication of the research paper [1] an error during the data analysis process was recognized. [...]
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Sustainability, Vol. 8, Pages 77: Determinants of Financial Sustainability for Farm Credit Applications—A Delphi Study
Farmers use credit from commercial credit providers to finance production activities. Commercial credit providers have to predict the financial sustainability of the enterprise to ensure that the borrower will have the ability to repay the loan. A Delphi study was conducted to explore what factors are used as indicators of loan-repayment ability of farmers. The objective was not only to identify factors that are currently considered, but also to identify other personal attributes that may improve the accuracy in predicting the repayment ability of potential borrowers. The Delphi was applied to a panel consisting of nine credit analysts and credit managers from a commercial credit provider in South Africa. The results indicate that the current and past financial performance, account standing, collateral, and credit record of the farm are very important in the assessment of applications in terms of financial performance. Experience and the success factors compared to competitors were found to be important, while age and education/qualification are regarded as less important in predicting repayment ability. The results also show that, although not currently objectively included in credit evaluations, credit analysis regards leadership and human relations; commitment and confidence; internal locus of control; self-efficacy; calculated risk taking; need for achievement; and opportunity seeking as important indicators of the ability of potential borrows to repay their loans. Thus, credit analysts and managers also regard management abilities and entrepreneurial characteristics of potential borrowers to be good indicators of repayment ability. Results from this research provide new indicator factors that can be used to extend existing credit evaluation instruments in order to more accurately predict repayment ability.
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Energies, Vol. 9, Pages 44: Screening Criteria and Considerations of Offshore Enhanced Oil Recovery
The application of enhanced oil recovery (EOR) in offshore oil fields has received significant attention due to the potentially enormous amount of recoverable oil. However, EOR application offshore is in its very early stage due to conditions that are more complex than onshore oil fields, owing to the unique parameters present offshore. Therefore, successful EOR applications in offshore oil fields require different screening criteria than those for conventional onshore applications. A comprehensive database for onshore applications of EOR processes together with a limited offshore EOR application database are analyzed in this paper, and the important parameters for successful offshore application are incorporated into the new EOR screening criteria. In this paper, screening criteria to determine acceptable EOR processes for offshore fields, including hydrocarbon gas miscible, CO2 miscible, and polymer processes, are presented. Suggested screening criteria for these EOR processes comprise quantitative boundaries and qualitative considerations. Quantitative screening criteria are predominantly based on quantifiable data, such as oil and reservoir properties. Qualitative screening considerations mainly focus on the operational issues present offshore, including platform space constraints, limited disposal options, injectant availability, and flow assurance matters (including hydrate formation and difficulties in emulsion separation).
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Remote Sensing, Vol. 8, Pages 62: Quantifying Multi-Decadal Change of Planted Forest Cover Using Airborne LiDAR and Landsat Imagery
Continuous monitoring of forest cover condition is key to understanding the carbon dynamics of forest ecosystems. This paper addresses how to integrate single-year airborne LiDAR and time-series Landsat imagery to derive forest cover change information. LiDAR data were used to extract forest cover at the sub-pixel level of Landsat for a single year, and the Landtrendr algorithm was applied to Landsat spectral data to explore the temporal information of forest cover change. Four different approaches were employed to model the relationship between forest cover and Landsat spectral data. The result shows incorporating the historic information using the temporal trajectory fitting process could infuse the model with better prediction power. Random forest modeling performs the best for quantitative forest cover estimation. Temporal trajectory fitting with random forest model shows the best agreement with validation data (R2 = 0.82 and RMSE = 5.19%). We applied our approach to Youyu county in Shanxi province of China, as part of the Three North Shelter Forest Program, to map multi-decadal forest cover dynamics. With the availability of global time-series Landsat imagery and affordable airborne LiDAR data, the approach we developed has the potential to derive large-scale forest cover dynamics.
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IJERPH, Vol. 13, Pages 128: Occupants’ Perceptions of Amenity and Efficiency for Verification of Spatial Design Adequacy
The best spatial design condition to satisfy the occupancy needs of amenity and efficiency is determined through analyzing the spatial design adequacy (SDA). In this study, the relationship between the space design elements and space on future occupants' perception are analyzed. The thirty-three participants reported their self-evaluated SDA that describes the quality of eight alternative housing living rooms with different spatial factors. The occupants were guided through the perception processing elaboration in order for them to evaluate the actual perception in the real space. The findings demonstrated that the spatial size (e.g., width, depth, and height) is significantly correlated with the overall satisfaction of amenity. It is also found that the spatial shape (e.g., the width-to-depth ratio, the height-to-area ratio, and room shape) may significantly influence the overall satisfaction of efficiency. The findings also demonstrate that the causal relationship between the spatial factors and space is clearly present in the occupants' perception, reflecting the time-sequential characteristics of the actual experience divided into amenity and efficiency. This result indicates that the correlation between the spatial factors and space of SDA under the occupants' perception processing elaboration can be a useful guide to predict the occupancy satisfaction of amenity and efficiency in real spaces.
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Crystals, Vol. 6, Pages 11: Accelerated Approach for the Band Structures Calculation of Phononic Crystals by Finite Element Method
We present here a fast and easily realized computational approach based on the finite element methods with consistent and lumped mass matrices (CM-FEM and LM-FEM, respectively), and the Bloch's theorem, to calculate the elastic band structures of phononic crystals. Two improvements, the adjustment of the introduction of Bloch's theorem as well as weighting treatment of consistent and lumped mass matrices, are performed. Numerical simulations show that convergence speed is accelerated obviously. Furthermore, the method is verified by analytical solutions in specified homogeneous cases. It is concluded that compared with CM-FEM or LM-FEM, the present method gives higher precision results with sparser mesh and takes less time.
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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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