Theoretical investigation of transgastric and intraductal approaches for ultrasound-based thermal therapy of the pancreas.

BackgroundThe goal of this study was to theoretically investigate the feasibility of intraductal and transgastric approaches to ultrasound-based thermal therapy of pancreatic tumors, and to evaluate possible treatment strategies.MethodsThis study considered ultrasound applicators with 1.2 mm outer diameter tubular transducers, which are inserted into the tissue to be treated by an endoscopic approach, either via insertion through the gastric wall (transgastric) or within the pancreatic duct lumen (intraductal). 8 patient-specific, 3D, transient, biothermal and acoustic finite element models were generated to model hyperthermia (n = 2) and ablation (n = 6), using sectored (210°-270°, n = 4) and 360° (n = 4) transducers for treatment of 3.3-17.0 cm3 tumors in the head (n = 5), body (n = 2), and tail (n = 1) of the pancreas. A parametric study was performed to determine appropriate treatment parameters as a function of tissue attenuation, blood perfusion rates, and distance to sensitive anatomy.ResultsParametric studies indicated that pancreatic tumors up to 2.5 or 2.7 cm diameter can be ablated within 10 min with the transgastric and intraductal approaches, respectively. Patient-specific simulations demonstrated that 67.1-83.3% of the volumes of four sample 3.3-11.4 cm3 tumors could be ablated within 3-10 min using transgastric or intraductal approaches. 55.3-60.0% of the volume of a large 17.0 cm3 tumor could be ablated using multiple applicator positions within 20-30 min with either transgastric or intraductal approaches. 89.9-94.7% of the volume of two 4.4-11.4 cm3 tumors could be treated with intraductal hyperthermia. Sectored applicators are effective in directing acoustic output away from and preserving sensitive structures. When acoustic energy is directed towards sensitive structures, applicators should be placed at least 13.9-14.8 mm from major vessels like the aorta, 9.4-12.0 mm from other vessels, depending on the vessel size and flow rate, and 14 mm from the duodenum.ConclusionsThis study demonstrated the feasibility of generating shaped or conformal ablative or hyperthermic temperature distributions within pancreatic tumors using transgastric or intraductal ultrasound

Gene expression profiles in the rat streptococcal cell wall-induced arthritis model identified using microarray analysis

Experimental arthritis models are considered valuable tools for delineating mechanisms of inflammation and autoimmune phenomena. Use of microarray-based methods represents a new and challenging approach that allows molecular dissection of complex autoimmune diseases such as arthritis. In order to characterize the temporal gene expression profile in joints from the reactivation model of streptococcal cell wall (SCW)-induced arthritis in Lewis (LEW/N) rats, total RNA was extracted from ankle joints from naïve, SCW injected, or phosphate buffered saline injected animals (time course study) and gene expression was analyzed using Affymetrix oligonucleotide microarray technology (RAE230A). After normalization and statistical analysis of data, 631 differentially expressed genes were sorted into clusters based on their levels and kinetics of expression using Spotfire(® )profile search and K-mean cluster analysis. Microarray-based data for a subset of genes were validated using real-time PCR TaqMan(® )analysis. Analysis of the microarray data identified 631 genes (441 upregulated and 190 downregulated) that were differentially expressed (Delta > 1.8, P < 0.01), showing specific levels and patterns of gene expression. The genes exhibiting the highest fold increase in expression on days -13.8, -13, or 3 were involved in chemotaxis, inflammatory response, cell adhesion and extracellular matrix remodelling. Transcriptome analysis identified 10 upregulated genes (Delta > 5), which have not previously been associated with arthritis pathology and are located in genomic regions associated with autoimmune disease. The majority of the downregulated genes were associated with metabolism, transport and regulation of muscle development. In conclusion, the present study describes the temporal expression of multiple disease-associated genes with potential pathophysiological roles in the reactivation model of SCW-induced arthritis in Lewis (LEW/N) rat. These findings improve our understanding of the molecular events that underlie the pathology in this animal model, which is potentially a valuable comparator to human rheumatoid arthritis (RA)

Photonic Quantum Logic with Narrowband Light from Single Atoms

Increasing control of single photons enables new applications of photonic quantum-enhanced technology and further experimental exploration of fundamental quantum phenomena. Here, we demonstrate quantum logic using narrow linewidth photons that are produced under nearly perfect quantum control from a single ^87Rb atom strongly coupled to a high-finesse cavity. We use a controlled- NOT gate integrated into a photonic chip to entangle these photons, and we observe non-classical correlations between events separated by periods exceeding the travel time across the chip by three orders of magnitude. This enables quantum technology that will use the properties of both narrowband single photon sources and integrated quantum photonics, such as networked quantum computing, narrow linewidth quantum enhanced sensing and atomic memories.Comment: 5 pates, 3 figure

Comparison of Heart Rate Responses Between Coronary Heart Disease and Age-Matched Normal Subjects in Water-and Land-Based Exercise: A Pilot Study

Background and purpose. Exercise therapy is an integral component of cardiac rehabilitation (CR). Currently, land-based exercise classes are prescribed in Phase IV CR. However, with its unique properties, water-based exercise potentially offers an alternative, or additional mode of exercise, that could be utilized by rehabilitating individuals. The purpose of this pilot study was to measure and compare the heart rate (HR) response and perception of exercise intensity between similar land-and water-based classes

Process evaluation of complex interventions: Medical Research Council guidance.

Process evaluation is an essential part of designing and testing complex interventions. New MRC guidance provides a framework for conducting and reporting process evaluation studiesThe work was funded by the MRC Population Health Science Research Network (PHSRN45).This is the final published version. It first appeared at http://www.bmj.com/content/350/bmj.h1258

Cold temperature does not affect perceived exertion in males and females during submaximal cycling

Background: Perceived exertion is an acknowledged indicator of exercise intensity and homeostasis disturbance of an individual, however, there are few studies that have examined the influence of cold temperatures on perceived exertion measurements. Cognition is crucial to perception and exposure to cold temperatures can elicit decrements in cognition. Aims & Objectives: The aim of this study was to determine if, and to what extent, exposure to cold environments may influence perceived exertion and cognitive ability. Study Design: Randomised controlled trial. Materials & Methods: Sixteen participants (m= 8, f= 8, age: 22.3 ± 1.7 years (mean ± SD)), completed two trials in a randomised order in COLD (5°C) and CONTROL (18 °C, 55% relative humidity) conditions. During each trial, following a standardised warm up, participants performed a 6-minute cycle ergometer submaximal exercise. Cognitive ability was assessed pre and post exercise with a reaction time (RT) test. Participant’s physiological responses were measured using Rate of Perceived Exertion (RPE), Heart Rate (HR), Oxygen consumption (VO2), Minute Ventilation (VE), Tympanic (Tt) and Skin Temperature (Tsk) continuously during testing. Statistics: Two-way repeated measures Analysis of Variances (ANOVA), were between environmental conditions over time.Data are reported as mean (M) ± standard deviation (SD).Ordinal Friedman ANOVA tests were conducted on RPE data between environmental conditions and gender. Non-parametric descriptive statistics were reported as medians (Mdn) and inter-quartile ranges (IQR) (25th–75thPercentile). Statistical significance was accepted at p 0.05) reported in RPE, VO2 and VEbetween COLD and CONTROL groups, however, significant decreases in Tsk(p= 0.001) and Tt(p= 0.001) were observed in COLD compared to CONTROL groups. Additionally, no significant differences (p > 0.05) in RT occurred between COLD and CONTROL. Furthermore, no significant differences in RPE were established between genders. Conclusions: Short-term exposure to cold temperatures does not significantly affect physical exertion perception or cognitive abilit

Dynamic shapes of the zygote and two-cell mouse and human

Mouse zygote morphokinetics were measured during interphase, the mitotic period, cytokinesis, and two-cell stage. Sequences of rounder–distorted–rounder shapes were revealed, as were changing patterns of cross section area. A calcium chelator and an actin-disrupting agent inhibited the area changes that occurred between pronuclear envelope breakdown and cytokinesis. During cell division, two vortices developed in each nascent cell and they rotated in opposite directions at each end of the cell, a pattern that sometimes persisted for up to 10 h. Exchange with the environment may have been promoted by these shape and area cycles and persisting circulation in the cytoplasm may have a similar function between a cell's interior and periphery. Some of these movements were sporadically also seen in human zygotes with abnormal numbers of pronuclei and the two-cell stages that developed from these compromised human zygotes

Life-history traits of the giant squid Architeuthis dux revealed from stable isotope signatures recorded in beaks

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