303 research outputs found
Effects of gabapentin on muscle spasticity and both induced as well as spontaneous autonomic dysreflexia after complete spinal cord injury
We recently reported that the neuropathic pain medication, gabapentin (GBP; Neurontin), significantly attenuated both noxious colorectal distension (CRD)-induced autonomic dysreflexia (AD) and tail pinch-induced spasticity compared to saline-treated cohorts 2–3 weeks after complete high thoracic (T4) spinal cord injury (SCI). Here we employed long-term blood pressure telemetry to test, firstly, the efficacy of daily versus acute GBP treatment in modulating AD and tail spasticity in response to noxious stimuli at 2 and 3 weeks post-injury. Secondly, we determined whether daily GBP alters baseline cardiovascular parameters, as well as spontaneous AD events detected using a novel algorithm based on blood pressure telemetry data. At both 14 and 21 days after SCI, irrespective of daily treatment, acute GBP given 1 h prior to stimulus significantly attenuated CRD-induced AD and pinch-evoked tail spasticity; conversely, acute saline had no such effects. Moreover, daily GBP did not alter 24 h mean arterial pressure (MAP) or heart rate (HR) values compared to saline treatment, nor did it reduce the incidence of spontaneous AD events compared to saline over the three week assessment period. Power spectral density (PSD) analysis of the MAP signals demonstrated relative power losses in mid frequency ranges (0.2–0.8 Hz) for all injured animals relative to low frequency MAP power (0.02–0.08 Hz). However, there was no significant difference between groups over time post-injury; hence, GBP had no effect on the persistent loss of MAP fluctuations in the mid frequency range after injury. In summary, the mechanism(s) by which acute GBP treatment mitigate aberrant somatosensory and cardiophysiological responses to noxious stimuli after SCI remain unclear. Nevertheless, with further refinements in defining the dynamics associated with AD events, such as eliminating requisite concomitant bradycardia, the objective repeatability of automatic detection of hypertensive crises provides a potentially useful tool for assessing autonomic function pre- and post-SCI, in conjunction with experimental pharmacotherapeutics for neuropathic pain, such as GBP
Glutathione <em>S</em>-transferase P1 (<em>GSTP1</em>) directly influences platinum drug chemosensitivity in ovarian tumour cell lines
BACKGROUND: Chemotherapy response in ovarian cancer patients is frequently compromised by drug resistance, possibly due to altered drug metabolism. Platinum drugs are metabolised by glutathione S-transferase P1 (GSTP1), which is abundantly, but variably expressed in ovarian tumours. We have created novel ovarian tumour cell line models to investigate the extent to which differential GSTP1 expression influences chemosensitivity. METHODS: Glutathione S-transferase P1 was stably deleted in A2780 and expression significantly reduced in cisplatin-resistant A2780DPP cells using Mission shRNA constructs, and MTT assays used to compare chemosensitivity to chemotherapy drugs used to treat ovarian cancer. Differentially expressed genes in GSTP1 knockdown cells were identified by Illumina HT-12 expression arrays and qRT–PCR analysis, and altered pathways predicted by MetaCore (GeneGo) analysis. Cell cycle changes were assessed by FACS analysis of PI-labelled cells and invasion and migration compared in quantitative Boyden chamber-based assays. RESULTS: Glutathione S-transferase P1 knockdown selectively influenced cisplatin and carboplatin chemosensitivity (2.3- and 4.83-fold change in IC(50), respectively). Cell cycle progression was unaffected, but cell invasion and migration was significantly reduced. We identified several novel GSTP1 target genes and candidate platinum chemotherapy response biomarkers. CONCLUSIONS: Glutathione S-transferase P1 has an important role in cisplatin and carboplatin metabolism in ovarian cancer cells. Inter-tumour differences in GSTP1 expression may therefore influence response to platinum-based chemotherapy in ovarian cancer patients
Psychological responses after a major fatal earthquake: The effect of preitraumatic dissociation and posttraumatic stress symptoms on anxiety and depression.
Following trauma, most people with initial symptoms of stress recover, but it is important to identify those at risk for continuing difficulties so resources are allocated appropriately. There has been limited investigation of predictors of posttraumatic stress disorder following natural disasters. This study assessed psychological difficulties experienced in 101 adult treatment seekers following exposure to a significant earthquake. Peritraumatic dissociation, posttraumatic stress symptoms, anxiety, depression, and emotional support were assessed. Path analysis was used to determine whether the experience of some psychological difficulties predicted the experience of other difficulties. As hypothesized, peritraumatic dissociation was found to predict posttraumatic stress symptoms and anxiety. Posttraumatic stress symptoms then predicted anxiety and depression. Depression and anxiety were highly correlated. Contrary to expectations, emotional support was not significantly related to other psychological variables. These findings justify the provision of psychological support following a natural disaster and suggest the benefit of assessing peritraumatic dissociation and posttraumatic stress symptoms soon after the event to identify people in need of monitoring and intervention
Effect of torso morphology on maximum hydrodynamic resistance in front crawl swimming
The aim of this study was to determine the influence of torso morphology on maximum instantaneous hydrodynamic resistance in front crawl swimming. Outlines of the torso in the frontal and anteroposterior planes were calculated from photographic images to determine continuous form gradients (m/m) for the anterior, posterior and lateral aspects of the torso. Torso cross-sectional areas at each vertical sample (0.001 m) were used to calculate maximal rate of change in cross-sectional area (m2/m) in the chest-waist and waist-hip segments. During the non-propulsive hand phase in middle-long distance front crawl, kicking propulsion is negligible and therefore the net force is equal to the drag. Drag coefficients were calculated at the instant of maximum horizontal deceleration of centre of mass during the non-propulsive hand phase of 400 m pace front crawl. Maximal rate of change in cross-sectional area (r = 0.44, p = 0.014) and posterior form gradient (r = 0.50, p = 0.006) of the waist-hip torso segment had moderate positive correlations with the maximal drag coefficient. A regression model including these variables explained 41% of the variance (p = 0.001). Indentation at the waist and curvature of the buttocks may result in greater drag force and influence swimming performance
The Star Formation Reference Survey. I. Survey Description and Basic Data
Star formation is arguably the most important physical process in the cosmos.
It is a fundamental driver of galaxy evolution and the ultimate source of most
of the energy emitted by galaxies. A correct interpretation of star formation
rate (SFR) measures is therefore essential to our understanding of galaxy
formation and evolution. Unfortunately, however, no single SFR estimator is
universally available or even applicable in all circumstances: the numerous
galaxies found in deep surveys are often too faint (or too distant) to yield
significant detections with most standard SFR measures, and until now there
have been no global, multi-band observations of nearby galaxies that span all
the conditions under which star-formation is taking place. To address this need
in a systematic way, we have undertaken a multi-band survey of all types of
star-forming galaxies in the local Universe. This project, the Star Formation
Reference Survey (SFRS), is based on a statistically valid sample of 369 nearby
galaxies that span all existing combinations of dust temperature, SFR, and
specific SFR. Furthermore, because the SFRS is blind with respect to AGN
fraction and environment it serves as a means to assess the influence of these
factors on SFR. Our panchromatic global flux measurements (including GALEX
FUV+NUV, SDSS ugriz, 2MASS JHKs, Spitzer 3-8{\mu}m, and others) furnish uniform
SFR measures and the context in which their reliability can be assessed. This
paper describes the SFRS survey strategy, defines the sample, and presents the
multi-band photometry collected to date.Comment: 48 pages, 12 figures, 10 tables. Accepted by PASP. This version
edited to correct references and typographical error
Modulation of detoxification gene expression in human colon HT29 cells by glutathione-S-transferase inhibitors
SUMMAR
PBjam: A Python package for automating asteroseismology of solar-like oscillators
Asteroseismology is an exceptional tool for studying stars by using the
properties of observed modes of oscillation. So far the process of performing
an asteroseismic analysis of a star has remained somewhat esoteric and
inaccessible to non-experts. In this software paper we describe PBjam, an
open-source Python package for analyzing the frequency spectra of solar-like
oscillators in a simple but principled and automated way. The aim of PBjam is
to provide a set of easy-to-use tools to extract information about the radial
and quadrupole oscillations in stars that oscillate like the Sun, which may
then be used to infer bulk properties such as stellar mass, radius and age or
even structure. Asteroseismology and its data analysis methods are becoming
increasingly important as space-based photometric observatories are producing a
wealth of new data, allowing asteroseismology to be applied in a wide range of
contexts such as exoplanet, stellar structure and evolution, and Galactic
population studies.Comment: 12 Pages, 4 figures. Accepted for publication in AJ. Associated
software available at https://doi.org/10.5281/zenodo.430007
Phase 2 study of canfosfamide in combination with pegylated liposomal doxorubicin in platinum and paclitaxel refractory or resistant epithelial ovarian cancer
<p>Abstract</p> <p>Background</p> <p>Canfosfamide is a novel glutathione analog activated by glutathione S-transferase P1-1. This study evaluated the safety and efficacy of canfosfamide in combination with pegylated liposomal doxorubicin (PLD) in patients with platinum resistant ovarian cancer. Patients with platinum resistant ovarian carcinoma and measurable disease received canfosfamide at 960 mg/m<sup>2 </sup>in combination with PLD at 50 mg/m<sup>2</sup>, intravenously day 1 in every 28 day cycles until tumor progression or unacceptable toxicities. The primary endpoints were objective response rate (ORR) and progression-free survival (PFS).</p> <p>Results</p> <p>Canfosfamide plus PLD combination therapy was administered at 960/50 mg/m<sup>2</sup>, respectively. Thirty-nine patients received a median number of 4 cycles (range 1.0-18.0). The ORR was 27.8% (95% CI, 14.2-45.2) with a disease stabilization rate of 80.6% (95% CI, 64.0-91.8) in the evaluable population. The CA-125 marker responses correlated with the radiological findings of complete response or partial response. The median PFS was 6.0 months (95% CI, 4.2-7.9) and median survival was 17.8 months. The combination was well tolerated. Myelosuppression was managed with dose reductions and growth factor support. Grade 3 febrile neutropenia was observed in 2 patients (5.1%). Non-hematologic adverse events occurred at the expected frequency and grade for each drug alone, with no unexpected or cumulative toxicities.</p> <p>Conclusions</p> <p>Canfosfamide in combination with PLD is well tolerated and active in platinum and paclitaxel refractory or resistant ovarian cancer. A randomized phase 3 study was conducted based on this supportive phase 2 study.</p> <p>Trial Registration</p> <p>This study was registered at www.clinicaltrials.gov: NCT00052065.</p
Collaborative European NeuroTrauma Effectiveness Research in Traumatic Brain Injury (CENTER-TBI): A Prospective Longitudinal Observational Study
BACKGROUND: Current classification of traumatic brain injury (TBI) is suboptimal, and management is based on weak evidence, with little attempt to personalize treatment. A need exists for new precision medicine and stratified management approaches that incorporate emerging technologies. OBJECTIVE: To improve characterization and classification of TBI and to identify best clinical care, using comparative effectiveness research approaches. METHODS: This multicenter, longitudinal, prospective, observational study in 22 countries across Europe and Israel will collect detailed data from 5400 consenting patients, presenting within 24 hours of injury, with a clinical diagnosis of TBI and an indication for computed tomography. Broader registry-level data collection in approximately 20 000 patients will assess generalizability. Cross sectional comprehensive outcome assessments, including quality of life and neuropsychological testing, will be performed at 6 months. Longitudinal assessments will continue up to 24 months post TBI in patient subsets. Advanced neuroimaging and genomic and biomarker data will be used to improve characterization, and analyses will include neuroinformatics approaches to address variations in process and clinical care. Results will be integrated with living systematic reviews in a process of knowledge transfer. The study initiation was from October to December 2014, and the recruitment period was for 18 to 24 months. EXPECTED OUTCOMES: Collaborative European NeuroTrauma Effectiveness Research in TBI should provide novel multidimensional approaches to TBI characterization and classification, evidence to support treatment recommendations, and benchmarks for quality of care. Data and sample repositories will ensure opportunities for legacy research. DISCUSSION: Comparative effectiveness research provides an alternative to reductionistic clinical trials in restricted patient populations by exploiting differences in biology, care, and outcome to support optimal personalized patient management
Diagnostic Accuracy of a Convolutional Neural Network Assessment of Solitary Pulmonary Nodules Compared With PET With CT Imaging and Dynamic Contrast-Enhanced CT Imaging Using Unenhanced and Contrast-Enhanced CT Imaging
Background: Solitary pulmonary nodules (SPNs) measuring 8 to 30 mm in diameter require further workup to determine the likelihood of malignancy. Research Question: What is the diagnostic performance of a lung cancer prediction convolutional neural network (LCP-CNN) in SPNs using unenhanced and contrast-enhanced CT imaging compared with the current clinical workup? Study Design and Methods: This was a post hoc analysis of the Single Pulmonary Nodule Investigation: Accuracy and Cost-Effectiveness of Dynamic Contrast Enhanced Computed Tomography in the Characterisation of Solitary Pulmonary Nodules trial, a prospective multicenter study comparing the diagnostic accuracy of dynamic contrast-enhanced (DCE) CT imaging with PET imaging in SPNs. The LCP-CNN was designed and validated in an external cohort. LCP-CNN-generated risk scores were created from the noncontrast and contrast-enhanced CT scan images from the DCE CT imaging. The gold standard was histologic analysis or 2 years of follow-up. The area under the receiver operating characteristic curves (AUC) were calculated using LCP-CNN score, maximum standardized uptake value, and DCE CT scan maximum enhancement and were compared using the DeLong test. Results: Two hundred seventy participants (mean ± SD age, 68.3 ± 8.8 years; 49% women) underwent PET with CT scan imaging and DCE CT imaging with CT scan data available centrally for LCP-CNN analysis. The accuracy of the LCP-CNN on the noncontrast images (AUC, 0.83; 95% CI, 0.79-0.88) was superior to that of DCE CT imaging (AUC, 0.76; 95% CI, 0.69-0.82; P = .03) and equal to that of PET with CT scan imaging (AUC, 0.86; 95% CI, 0.81-0.90; P = .35). The presence of contrast resulted in a small reduction in diagnostic accuracy, with the AUC falling from 0.83 (95% CI, 0.79-0.88) on the noncontrast images to 0.80 to 0.83 after contrast (P < .05 for 240 s after contrast only). Interpretation: An LCP-CNN algorithm provides an AUC equivalent to PET with CT scan imaging in the diagnosis of solitary pulmonary nodules. Trial Registration: ClinicalTrials.gov Identifier; No.: NCT0201306
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