Comparison of manual and semi-automated delineation of regions of interest for radioligand PET imaging analysis

BACKGROUND As imaging centers produce higher resolution research scans, the number of man-hours required to process regional data has become a major concern. Comparison of automated vs. manual methodology has not been reported for functional imaging. We explored validation of using automation to delineate regions of interest on positron emission tomography (PET) scans. The purpose of this study was to ascertain improvements in image processing time and reproducibility of a semi-automated brain region extraction (SABRE) method over manual delineation of regions of interest (ROIs). METHODS We compared 2 sets of partial volume corrected serotonin 1a receptor binding potentials (BPs) resulting from manual vs. semi-automated methods. BPs were obtained from subjects meeting consensus criteria for frontotemporal degeneration and from age- and gender-matched healthy controls. Two trained raters provided each set of data to conduct comparisons of inter-rater mean image processing time, rank order of BPs for 9 PET scans, intra- and inter-rater intraclass correlation coefficients (ICC), repeatability coefficients (RC), percentages of the average parameter value (RM%), and effect sizes of either method. RESULTS SABRE saved approximately 3 hours of processing time per PET subject over manual delineation (p 0.8) for both methods. RC and RM% were lower for the manual method across all ROIs, indicating less intra-rater variance across PET subjects' BPs. CONCLUSION SABRE demonstrated significant time savings and no significant difference in reproducibility over manual methods, justifying the use of SABRE in serotonin 1a receptor radioligand PET imaging analysis. This implies that semi-automated ROI delineation is a valid methodology for future PET imaging analysis

Virulence behavior of uropathogenic Escherichia coli strains in the host model Caenorhabditis elegans

Urinary tract infections (UTIs) are among the most common bacterial infections in humans. Although a number of bacteria can cause UTIs, most cases are due to infection by uropathogenic Escherichia coli (UPEC). UPEC are a genetically heterogeneous group that exhibit several virulence factors associated with colonization and persistence of bacteria in the urinary tract. Caenorhabditis elegans is a tiny, free-living nematode found worldwide. Because many biological pathways are conserved in C. elegans and humans, the nematode has been increasingly used as a model organism to study virulence mechanisms of microbial infections and innate immunity. The virulence of UPEC strains, characterized for antimicrobial resistance, pathogenicity-related genes associated with virulence and phylogenetic group belonging was evaluated by measuring the survival of C. elegans exposed to pure cultures of these strains. Our results showed that urinary strains can kill the nematode and that the clinical isolate ECP110 was able to efficiently colonize the gut and to inhibit the host oxidative response to infection. Our data support that C. elegans, a free-living nematode found worldwide, could serve as an in vivo model to distinguish, among uropathogenic E. coli, different virulence behavior

Results of a phase-I/II randomized, masked, placebo-controlled trial of recombinant human interleukin-11 (rhIL-11) in the treatment of subjects with active rheumatoid arthritis

Interleukin-11 (IL-11) is a pleiotropic cytokine that regulates the growth and development of hematopoietic stem cells and decreases the proinflammatory mediators of cytokine and nitric oxide production. In animal models of arthritis, treatment with recombinant human IL-11 (rhIL-11) reduces both the level of synovitis and the histologic lesion scores in the joints. The goal of this phase-I/II study in adults with rheumatoid arthritis (RA) was to evaluate the safety and clinical activity of different doses and schedules of rhIL-11 in patients with active RA for whom treatment with at least one disease-modifying antirheumatic drug had failed. This was a multicenter, randomized, placebo-controlled trial that evaluated the safety and tolerability of rhIL-11 in 91 patients with active RA. rhIL-11 was administered subcutaneously; patients were randomized into one of five treatment groups (ratio of rhIL-11 to placebo, 4:1). Patients were treated for 12 weeks with either 2.5 or 7.5 μg/kg of rhIL-11 or placebo twice per week or 5 or 15 μg/kg of rhIL-11 or placebo once per week. The status of each subject's disease activity in accordance with the American College of Rheumatology (ACR) criteria was assessed before, during, and after completion of administration of the study drug. Administration of rhIL-11 was well tolerated at all doses and schedules. The most frequent adverse event was a reaction at the injection site. The data suggest a statistically significant reduction in the number of tender joints (P < 0.008) at the 15 μg/kg once-weekly dose schedule but showed no overall significant benefit at the ACR criterion of a 20% response. The trial showed rhIL-11 to be safe and well tolerated at a variety of doses and schedules over a 12-week treatment period in patients with active RA. The only adverse event clearly associated with rhIL-11 administration was reaction at the injection site

Targeted Deletion of HIF-1α Gene in T Cells Prevents their Inhibition in Hypoxic Inflamed Tissues and Improves Septic Mice Survival

Sepsis patients may die either from an overwhelming systemic immune response and/or from an immunoparalysis-associated lack of anti-bacterial immune defence. We hypothesized that bacterial superantigen-activated T cells may be prevented from contribution into anti-bacterial response due to the inhibition of their effector functions by the hypoxia inducible transcription factor (HIF-1alpha) in inflamed and hypoxic areas.Using the Cre-lox-P-system we generated mice with a T-cell targeted deletion of the HIF-1alpha gene and analysed them in an in vivo model of bacterial sepsis. We show that deletion of the HIF-1alpha gene leads to higher levels of pro-inflammatory cytokines, stronger anti-bacterial effects and much better survival of mice. These effects can be at least partially explained by significantly increased NF-kappaB activation in TCR activated HIF-1 alpha deficient T cells.T cells can be recruited to powerfully contribute to anti-bacterial response if they are relieved from inhibition by HIF-1alpha in inflamed and hypoxic areas. Our experiments uncovered the before unappreciated reserve of anti-bacterial capacity of T cells and suggest novel therapeutic anti-pathogen strategies based on targeted deletion or inhibition of HIF-1 alpha in T cells

International Veterinary Epilepsy Task Force consensus proposal: Medical treatment of canine epilepsy in Europe

In Europe, the number of antiepileptic drugs (AEDs) licensed for dogs has grown considerably over the last years. Nevertheless, the same questions remain, which include, 1) when to start treatment, 2) which drug is best used initially, 3) which adjunctive AED can be advised if treatment with the initial drug is unsatisfactory, and 4) when treatment changes should be considered. In this consensus proposal, an overview is given on the aim of AED treatment, when to start long-term treatment in canine epilepsy and which veterinary AEDs are currently in use for dogs. The consensus proposal for drug treatment protocols, 1) is based on current published evidence-based literature, 2) considers the current legal framework of the cascade regulation for the prescription of veterinary drugs in Europe, and 3) reflects the authors’ experience. With this paper it is aimed to provide a consensus for the management of canine idiopathic epilepsy. Furthermore, for the management of structural epilepsy AEDs are inevitable in addition to treating the underlying cause, if possible

Planning the integration and test of a space telescope with a 1 m aluminum primary mirror: the Ariel mission case

Ariel (Atmospheric Remote-Sensing Infrared Exoplanet Large Survey) is ESA’s M4 mission of the “Cosmic Vision” program, with launch scheduled for 2029. Its purpose is to conduct a survey of the atmospheres of known exoplanets through transit spectroscopy. Ariel is based on a 1 m class telescope optimized for spectroscopy in the waveband between 1.95 and 7.8 µm, operating at cryogenic temperatures in the range 40–50 K. The Ariel Telescope is an off-axis, unobscured Cassegrain design, with a parabolic recollimating tertiary mirror and a flat folding mirror directing the output beam parallel to the optical bench. The secondary mirror is mounted on a roto-translating stage for adjustments during the mission. The mirrors and supporting structures are all realized in an aerospace-grade aluminum alloy T6061 for ease of manufacturing and thermalization. The low stiffness of the material, however, poses unique challenges to integration and alignment. Care must be therefore employed when designing and planning the assembly and alignment procedures, necessarily performed at room temperature and with gravity, and the optical performance tests at cryogenic temperatures. This paper provides a high-level description of the Assembly, Integration and Test (AIT) plan for the Ariel telescope and gives an overview of the analyses and reasoning that led to the specific choices and solutions adopted

Measurement of the Charged Multiplicities in b, c and Light Quark Events from Z0 Decays

Average charged multiplicities have been measured separately in $b$, $c$ and light quark ($u,d,s$) events from $Z^0$ decays measured in the SLD experiment. Impact parameters of charged tracks were used to select enriched samples of $b$ and light quark events, and reconstructed charmed mesons were used to select $c$ quark events. We measured the charged multiplicities: $\bar{n}_{uds} = 20.21 \pm 0.10 (\rm{stat.})\pm 0.22(\rm{syst.})$, $\bar{n}_{c} = 21.28 \pm 0.46(\rm{stat.}) ^{+0.41}_{-0.36}(\rm{syst.})$ $\bar{n}_{b} = 23.14 \pm 0.10(\rm{stat.}) ^{+0.38}_{-0.37}(\rm{syst.})$, from which we derived the differences between the total average charged multiplicities of $c$ or $b$ quark events and light quark events: $\Delta \bar{n}_c = 1.07 \pm 0.47(\rm{stat.})^{+0.36}_{-0.30}(\rm{syst.})$ and $\Delta \bar{n}_b = 2.93 \pm 0.14(\rm{stat.})^{+0.30}_{-0.29}(\rm{syst.})$. We compared these measurements with those at lower center-of-mass energies and with perturbative QCD predictions. These combined results are in agreement with the QCD expectations and disfavor the hypothesis of flavor-independent fragmentation.Comment: 19 pages LaTex, 4 EPS figures, to appear in Physics Letters

A Search for Jet Handedness in Hadronic Z0Z^0 Decays

We have searched for signatures of polarization in hadronic jets from $Z^0 \to q \bar{q}$ decays using the ``jet handedness'' method. The polar angle asymmetry induced by the high SLC electron-beam polarization was used to separate quark jets from antiquark jets, expected to be left- and right-polarized, respectively. We find no evidence for jet handedness in our global sample or in a sample of light quark jets and we set upper limits at the 95% C.L. of 0.063 and 0.099 respectively on the magnitude of the analyzing power of the method proposed by Efremov {\it et al.}Comment: Revtex, 8 pages, 2 figure