This Perspective gives an overview of the definitions, advantages, and the importance of behavioral studies in ecotoxicology. Recent developments in automated quantitative recording technology as ...well as in mathematical data analysis and statistical data treatment have given rise to increased research in behavioral ecotoxicology. As an example, several studies performed with different invertebrate and vertebrate species using the non-optical impedance recorder, the Multispecies Freshwater Biomonitor™, are mentioned and discussed under the aspect of recent developments. However, some problems have still to be solved, such as (1) linking behavior to other biological test parameters on the suborganismal as well as the population level, (2) standardization of test designs and methods, and (3) creating more acceptance of these methods in the legislative framework of biomonitoring.
In this study, evidence is provided for supporting siblings as a standard of care in pediatric oncology. Using Medline, PsycInfo, and CINAHL, a systematic search of articles published over the past ...two decades about siblings of children with cancer was conducted. A total of 125 articles, which were primarily descriptive studies, were evaluated by the four investigators using Grading of Recommendations Assessment, Development, and Evaluation (GRADE) criteria. There is moderate‐quality evidence, as well as support from community stakeholders, to justify a strong recommendation that siblings of children with cancer should be provided with psychosocial services and that parents and professionals are advised about how to meet siblings’ needs.
Regeneration after severe peripheral nerve injury is often poor. Knowledge of human nerve regeneration and the growth microenvironment is greatly lacking. We aimed to identify the regenerative ...proteins in human peripheral nerve by comparing the proteome before and after a transection injury. In a unique study design, we collected closely matched samples of naïve and injured sural nerve. Naïve and injured (two weeks after injury) samples were analyzed using mass spectrometry and immunoassays. We found significantly altered levels following the nerve injury. Mass spectrometry revealed that injury samples had 568 proteins significantly upregulated and 471 significantly downregulated compared to naïve samples (q-value ≤ 0.05 and Z ≥ |2| (log2)). We used Gene Ontology (GO) pathway overrepresentation analysis to highlight groups of proteins that were significantly upregulated or downregulated with injury-induced degeneration and regeneration. Significant protein changes in key pathways were identified including growth factor levels, Schwann cell de-differentiation, myelination downregulation, epithelial-mesenchymal transition (EMT), and axonal regeneration pathways. The proteomes of the uninjured nerve compared to the degenerating/regenerating nerve may reveal biomarkers to aid in the development of repair strategies such as infusing supplemental trophic factors and in monitoring neural tissue regeneration.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
In this research, transparent conductive films of indium tin oxide (ITO) were deposited by solution processing sol–gel ink through spin coating on soda-lime glass and sheet glass substrates. The ...processing parameters evaluated include the deposition humidity, spin coating speed, and ink concentration. The optical transmittance of the ITO thin films was collected by UV–vis spectrophotometry, while the electrical properties were studied by sheet resistance measurements and impedance spectroscopy (IS) using an in-plane configuration. The lowest sheet resistance achieved for a single layer film is 104 Ω/□, with a corresponding low frequency impedance magnitude of 2 × 105. These values were obtained at medium humidity values while maintaining high optical transparency (>90%) in the visible light region. High humidity values were found to affect the substrate wetting property of the ITO ink and increased the possibility of hydrolysis during deposition, resulting in the formation of non-uniform surface patterns. A spin coating speed of 4000 rpm or more is required to obtain a uniform ITO film with desirable electrical and optical properties. Once the optimum combination of parameters is obtained, the sheet resistance and impedance magnitude can be reduced to ∼102 Ω/□ through multilayer deposition and annealing in a reducing atmosphere with minimal effect on the optical transmittance (>90%) and surface morphology, making these materials useful as electrodes for electro-optic applications. When the optimal values of the main deposition parameters are used, the ink concentration was found to have minimal effect on the quality and properties of the ITO films.
Nanocomposite sensors consisting of carbon fiber microelectrodes modified with Nafion® and carbon nanotubes, and ceramic-based microelectrode biosensor arrays were used to measure ascorbate and ...glutamate in the brain with high spatial, temporal and chemical resolution. Nanocomposite sensors displayed electrocatalytic properties towards ascorbate oxidation, translated into a negative shift from +0.20V to −0.05V vs. Ag/AgCl, as well as a significant increase (10-fold) of electroactive surface area. The estimated average basal concentration of ascorbate in vivo in the CA1, CA3 and dentate gyrus (DG) sub regions of the hippocampus were 276±60μM (n=10), 183±30μM (n=10) and 133±42μM (n=10), respectively. The glutamate microbiosensor arrays showed a high sensitivity of 5.3±0.8pAμM−1 (n=18), and LOD of 204±32nM (n=10), and t50% response time of 0.9±0.02s (n=6) and high selectivity against major interferents. The simultaneous and real-time measurements of glutamate and ascorbate in the hippocampus of anesthetized rats following local stimulus with KCl or glutamate revealed a dynamic interaction between the two neurochemicals.
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•Basal ascorbate was measured in vivo in the hippocampus with a nanocomposite sensor.•A microbiosensor array was characterized and used for in vivo glutamate measurements.•Simultaneous monitoring of ascorbate and glutamate in anesthetized rat is reported.
Multiwalled carbon nanotubes (MWCNTs) are a one-dimensional nanomaterial with several desirable material properties, including high mechanical tensile modulus and strength, high electrical ...conductivity, and good thermal conductivity. A wide variety of techniques have been optimized to synthesize MWCNTs and to fabricate thin films of MWCNTs. These synthesis and fabrication methods vary based on precursor materials, process parameters, and physical and chemical principals, and have a strong influence on the properties of the nanotubes and films. Thus, the fabrication methods determine the performance of devices that can exploit the advantageous material properties of MWCNTs. Techniques for the fabrication of carbon nanotubes and carbon nanotube thin films are reviewed, followed by a discussion of the use of MWCNTs as an electrode material for electrochemical double-layer supercapacitors (EDLCs). EDLCs feature high power density, excellent reversibility and lifetime, and improved energy density over electrolytic capacitors. Beyond surveying fabrication techniques previously explored for MWCNT electrodes, an alternative approach based on inkjet printing capable of depositing a small amount of active material is discussed. Such an approach allows for a high degree of control over electrode properties and can potentially reduce cost and active material waste, which are essential components to the gradual conversion to green energy.
A self-referencing technique utilizing two microelectrodes on a ceramic-based multisite array is employed for confirmation and elimination of interferences detected by enzyme-based microelectrodes. ...The measurement of l-glutamate using glutamate oxidase was the test system; however, other oxidase enzymes such as glucose oxidase can be employed. One recording site was coated with Nafion with l-glutamate oxidase and bovine serum albumin (BSA) cross-linked with glutaraldehyde while the other had Nafion with BSA cross-linked with glutaraldehyde. Differences in the chemistry of the two recording sites allowed for identification and elimination of interfering signals to be removed from the analyte response. The electrode showed low detection limits (LOD = 0.98 ± 0.09 μM, signal-to-noise ratio of 3), fast response times (T 90 ∼1 s), and excellent linearity (R 2 = 0.999 ± 0.000) over the concentration range of 0−200 μM for calibrations of l-glutamate in vitro. The selectivity and dimensions of the multisite electrode allow in vivo glutamate measurements. This electrode has been applied to in vivo measurements of the clearance of locally applied glutamate and release of glutamate in the prefrontal cortex of anesthetized rats. In addition, a similar approach has been applied to the development of a microelectrode for measures of glucose.
Spreading depolarization (SD) is a slow propagating wave of strong depolarization of neural cells, implicated in several neuropathological conditions. The breakdown of brain homeostasis promotes ...significant hemodynamic and metabolic alterations, which impacts on neuronal function. In this work we aimed to develop an innovative multimodal approach, encompassing metabolic, electric and hemodynamic measurements, tailored but not limited to study SD. This was based on a novel dual-biosensor based on microelectrode arrays designed to simultaneously monitor lactate and glucose fluctuations and ongoing neuronal activity with high spatial and temporal resolution. In vitro evaluation of dual lactate-glucose microbiosensor revealed an extended linear range, high sensitivity and selectivity, fast response time and low oxygen-, temperature- and pH- dependencies. In anesthetized rats, we measured with the same array a significant drop in glucose concentration matched to a rise in lactate and concurrently with pronounced changes in the spectral profile of LFP-related currents during episodes of mechanically-evoked SD. This occurred along with the stereotypical hemodynamic response of the SD wave. Overall, this multimodal approach successfully demonstrates the capability to monitor metabolic alterations and ongoing electrical activity, thus contributing to a better understanding of the metabolic changes occurring in the brain following SD.
Aims
To examine the impact of errors or adverse events on emotional distress and professional quality of life in healthcare providers in the neonatal intensive care unit, and the moderating role of ...coworker support.
Background
Errors or adverse events can result in negative outcomes for healthcare providers. However, the role of coworker support in improving emotional and professional outcomes has not been examined.
Design
A cross‐sectional online survey from a quality improvement initiative to train peer supporters in a neonatal intensive care unit.
Methods
During 2015, 463 healthcare providers in a neonatal intensive care unit completed a survey assessing their experiences with an error or adverse event, anxiety, depression, professional quality of life and coworker support.
Results
Compared with those who did not experience an error or adverse event (58%), healthcare providers who observed (23%) or were involved (19%) in an incident reported higher levels of anxiety and secondary traumatic stress. Those who were involved in an event reported higher levels of depression and burnout. Differences between the three groups (no event, observation and involvement) for compassion satisfaction were non‐significant. Perceived coworker support moderated the association between experiencing an event and both anxiety and depression. Specifically, experiencing an event was associated with higher levels of anxiety and depression when coworkers were perceived as low in supportiveness, but not when they were viewed as highly supportive.
Conclusion
Findings suggest that errors or adverse events can have a harmful impact on healthcare providers and that coworker support may reduce emotional distress.
Direct measurement of glucose in the brain extracellular space with high spatial and temporal resolution is needed for understanding of brain energy metabolism. In this work we developed and ...extensively characterized an amperometric glucose microbiosensor using ceramic-based platinum multisite microelectrode arrays (MEAs) for measuring extracellular glucose in the rat brain in vivo. Glucose-oxidase (GOx) was immobilized at the microelectrode surface by cross-linking with glutaraldehyde in the presence of BSA. The in vitro evaluations supported the high analytical performance of these microbiosensors for application in the brain, including high selectivity and sensitivity, adequate linear range and limit of detection, good operational stability and response time, minimal oxygen-, pH- and temperature-dependencies. The microbiosensors were successfully used for measurements of glucose with high temporal and spatial resolution in the hippocampus of anesthetized rats in response to systemic, local glucose changes and upon glutamatergic stimulation. Overall, the results support the suitability of these microbiosensors for measuring rapid changes of extracellular glucose in the rat brain.
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