Melanocytes are selectively vulnerable to UVA-mediated bystander oxidative signaling.

Long-wave UVA is the major component of terrestrial UV radiation and is also the predominant constituent of indoor sunlamps, both of which have been shown to increase cutaneous melanoma risk. Using a two-chamber model, we show that UVA-exposed target cells induce intercellular oxidative signaling to non-irradiated bystander cells. This UVA-mediated bystander stress is observed between all three cutaneous cell types (i.e., keratinocytes, melanocytes, and fibroblasts). Significantly, melanocytes appear to be more resistant to direct UVA effects compared with keratinocytes and fibroblasts, although melanocytes are also more susceptible to bystander oxidative signaling. The extensive intercellular flux of oxidative species has not been previously appreciated and could possibly contribute to the observed cancer risk associated with prolonged UVA exposure

Signal quality measures for unsupervised blood pressure measurement

Accurate systolic and diastolic pressure estimation, using automated blood pressure measurement, is difficult to achieve when the transduced signals are contaminated with noise or interference, such as movement artifact. This study presents an algorithm for automated signal quality assessment in blood pressure measurement by determining the feasibility of accurately detecting systolic and diastolic pressures when corrupted with various levels of movement artifact. The performance of the proposed algorithm is compared to a manually annotated reference scoring (RS). Based on visual representations and audible playback of Korotkoff sounds, the creation of the RS involved two experts identifying sections of the recorded sounds and annotating sections of noise contamination. The experts determined the systolic and diastolic pressure in 100 recorded Korotkoff sound recordings, using a simultaneous electrocardiograph as a reference signal. The recorded Korotkoff sounds were acquired from 25 healthy subjects (16 men and 9 women) with a total of four measurements per subject. Two of these measurements contained purposely induced noise artifact caused by subject movement. Morphological changes in the cuff pressure signal and the width of the Korotkoff pulse were extracted features which were believed to be correlated with the noise presence in the recorded Korotkoff sounds. Verification of reliable Korotkoff pulses was also performed using extracted features from the oscillometric waveform as recorded from the inflatable cuff. The time between an identified noise section and a verified Korotkoff pulse was the key feature used to determine the validity of possible systolic and diastolic pressures in noise contaminated Korotkoff sounds. The performance of the algorithm was assessed based on the ability to: verify if a signal was contaminated with any noise; the accuracy, sensitivity and specificity of this noise classification, and the systolic and diastolic pressure differences between the result obtained from the algorithm and the RS. 90% of the actual noise contaminated signals were correctly identified, and a sample-wise accuracy, sensitivity and specificity of 97.0%, 80.61% and 98.16%, respectively, were obtained from 100 pooled signals. The mean systolic and diastolic differences were 0.37 ± 3.31 and 3.10 ± 5.46 mmHg, respectively, when the artifact detection algorithm was utilized, with the algorithm correctly determined if the signal was clean enough to attempt an estimation of systolic or diastolic pressures in 93% of blood pressure measurements

A Biogeographic Study of Amphibians in Tennessee

Range maps and descriptive, taxonomic, and habitat information are provided for 20 species of frogs and 41 species of salamanders. The environmental setting of Tennessee is described in terms of geology, physiography, climate, drainages, soils, vegetation, and ecoregions. For the purposes of the analyses, a grid cell pattern containing 122 sampling units is used, and the amphibian fauna is organized into three faunal groups. These groups are frog species, salamander species, and all species grouped together as amphibians. The results of a G-test for the frequency distribution of range limits fitted to a Poisson distribution suggest a clumped dispersion pattern for each faunal group. Using the coefficient of Jaccard, cluster analyses of distribution data delineate three areas of faunal homogeneity for frogs, nine for salamanders, and six for all amphibians. Coefficients of correlation of similarity matrices are calculated and indicate that (1) the geographic distribution patterns of both frogs and salamanders are most closely correlated with the patterns of climate, soils, and physiography; and (2) when compared to frogs, salamander distributions exert a larger influence on the determination of amphibian areas of homogeneity. An analysis of the faunal composition of areas of homogeneity in terms of past dispersal patterns of their component species reveals that frog areas are dominated by species that dispersed from southeastern, southwestern, and southern centers of dispersal while salamander areas are dominated by species with an Appalachian Highland center of dispersal. Simple correlation and stepwise multiple regression analyses of the relationships between frog, salamander, and amphibian species densities and values for 17 environmental variables indicate that frogs and salamanders exhibit diametrically different responses to a majority of the environmental gradients studied. Modified by historical factors, aspects of the evolutionary time, ecological time, and spatial heterogeneity theories are used to tentatively explain these density gradients. Frog and salamander faunas of Tennessee exhibit significantly different biogeographic patterns. This is evident in both a study of areas of faunal homogeneity and an analysis of species densities. Results from analyses of total amphibian fauna obscure the unique characteristics of each faunal group

One-pot near-ambient temperature syntheses of aryl(difluoroenol) derivatives from trifluoroethanol

Difluoroalkenylzinc reagents prepared from 1-(2’-methoxy-ethoxymethoxy)-2,2,2-trifluoroethane and 1-(N,N-diethylcarbamoyloxy)-2,2,2-trifluoroethane at ice bath temperatures, underwent Negishi coupling with a range of aryl halides in a convenient one pot procedure. While significant differences between the enol acetal and carbamate reagents were revealed, the Negishi protocol compared very favourably with alternative coupling procedures in terms of overall yields from trifluoroethanol

Analytic perturbation theory in QCD and Schwinger's connection between the beta-function and the spectral density

We argue that a technique called analytic perturbation theory leads to a well-defined method for analytically continuing the running coupling constant from the spacelike to the timelike region, which allows us to give a self-consistent definition of the running coupling constant for timelike momentum. The corresponding $\beta$-function is proportional to the spectral density, which confirms a hypothesis due to Schwinger.Comment: 11 pages, 2 figure

The NCBO OBOF to OWL Mapping

Two of the most significant formats for biomedical ontologies are the Open Biomedical Ontologies Format (OBOF) and the Web Ontology Language (OWL). To make it possible to translate ontologies between these two representation formats, the National Center for Biomedical Ontology (NCBO) has developed a mapping between the OBOF and OWL formats as well as inter-conversion software. The goal was to allow the sharing of tools, ontologies, and associated data between the OBOF and Semantic Web communities.

OBOF does not have a formal grammar, so the NCBO had to capture its intended semantics to map it to OWL.

This official NCBO mapping was used to make all OBO Foundry ontologies available in OWL. 

Availability: This mapping functionality can be embedded into OBO-Edit and Protégé-OWL ontology editors. This software is available at: http://bioontology.org/wiki/index.php/OboInOwl:Main_Pag

Estimating Lower Limb Kinematics using a Lie Group Constrained EKF and a Reduced Wearable IMU Count

This paper presents an algorithm that makes novel use of a Lie group representation of position and orientation alongside a constrained extended Kalman filter (CEKF) to accurately estimate pelvis, thigh, and shank kinematics during walking using only three wearable inertial sensors. The algorithm iterates through the prediction update (kinematic equation), measurement update (pelvis height, zero velocity update, flat-floor assumption, and covariance limiter), and constraint update (formulation of hinged knee joints and ball-and-socket hip joints). The paper also describes a novel Lie group formulation of the assumptions implemented in the said measurement and constraint updates. Evaluation of the algorithm on nine healthy subjects who walked freely within a $4 \times 4$ m$^2$ room shows that the knee and hip joint angle root-mean-square errors (RMSEs) in the sagittal plane for free walking were $10.5 \pm 2.8^\circ$ and $9.7 \pm 3.3^\circ$, respectively, while the correlation coefficients (CCs) were $0.89 \pm 0.06$ and $0.78 \pm 0.09$, respectively. The evaluation demonstrates a promising application of Lie group representation to inertial motion capture under reduced-sensor-count configuration, improving the estimates (i.e., joint angle RMSEs and CCs) for dynamic motion, and enabling better convergence for our non-linear biomechanical constraints. To further improve performance, additional information relating the pelvis and ankle kinematics is needed.Comment: 6 pages. arXiv admin note: text overlap with arXiv:1910.0091

P38 MAP Kinase inhibition promotes primary tumour growth via VEGF independent mechanism

<p>Abstract</p> <p>Background</p> <p>The surgical insult induces an inflammatory response that activates P38 MAP kinases and solid tumours can also release cytokines. Therfore inhibition of these pathways may reduce tumour growth We set out to examine the effects of P38-MAPK inhibition on apoptosis, proliferation, VEGF release and cell cycle effects <it>in-vitro </it>and on primary tumour growth <it>in-vivo</it>.</p> <p>Methods</p> <p>4T-1 cells (2 × 10⁵cells/well) were incubated, in 24 well plates with control, 25, 50 or 100 ng/ml of SB-202190 for 24 hours. Cells were subsequently asessed for apoptosis, proliferation, VEGF release and cell cycle analysis. Balb-c mice each received 1 × 10⁶4T1 cells subcutaneously in the flank and were then randomised to receive control or SB202190 (2.5 μM/kg) by intraperitoneal injection daily. Tumour size was measured alternate days and at day 24 animals were sacrificed and serum VEGF assessed.</p> <p>Results</p> <p>P38-MAPK inhibition <it>in-vitro </it>resulted in a significant reduction in proliferation (75.2 ± 8.4% vs. 100 ± 4.3%, p < 0.05) and G₁cell cycle phase(35.9 ± 1.1% vs. 32.5 ± 0.6%, p < 0.05) but no significant changes in apoptosis or VEGF levels. <it>In-vivo</it>, P38-MAPK inhibition resulted in an increase in primary tumour growth (155.6 ± 34.9 vs. 86.7 ± 18.2 mm³, p < 0.05). P38-MAPK inhibition also lowered circulating VEGF levels but this difference was not significant (101.9 ± 27.1 ηg/ml compared to 158.6 ± 27.1 ηg/ml)</p> <p>Conclusion</p> <p>These findings demonstrate that P38-MAPK inhibition in-vitro reduces proliferation and G₁cell cycle phase as well as promoting primary tumour growth in-vivo. These effects would appear to be independent of VEGF.</p