STE2/SCG1-dependent inhibition of STE4-induced growth arrest by mutant STE4ΔC6 in the yeast pheromone response pathway

AbstractThe yeast pheromone response pathway involves the activation of a heterotrimeric G protein composed by SCGI (α) (also GPA1), STE4 (β), and STE18 (γ) subunits by the pheromone-activated receptors STE2 and STE3 in a and α cells, respectively. Upon exchange of bound GDP for GTP in the SCG1 subunit, the release of STE4/STE18 dimer occurs which, in turn causes activation of downstream effectors leading growth arrest and mating competence. Over-expression of STE4 also leads to growth arrest in a STE18 dependent manner. Removal of 6 amino acids from the C-terminus of STE4 rendered a subunit incapable of downstream signalling but still able to interact with STE18. This ΔC6 mutant acts as a dominant negative because it blocks the growth arresting effect obtained by over-expression of STE4. The inhibitory effect of STE4ΔC6 is dependent on the presence of the SCG1 subunit in a STE2 but not ste2 background. Inhibition of the growth arresting effect of STE4 by the ΔC6 mutant is not due to competition at the effector site, but rather involves an intrinsic activity of STE2 that is dependent on SCG1

Vaccination against GIP for the Treatment of Obesity

BACKGROUND: According to the WHO, more than 1 billion people worldwide are overweight and at risk of developing chronic illnesses, including cardiovascular disease, type 2 diabetes, hypertension and stroke. Current therapies show limited efficacy and are often associated with unpleasant side-effect profiles, hence there is a medical need for new therapeutic interventions in the field of obesity. Gastric inhibitory peptide (GIP, also known as glucose-dependent insulinotropic polypeptide) has recently been postulated to link over-nutrition with obesity. In fact GIP receptor-deficient mice (GIPR(-/-)) were shown to be completely protected from diet-induced obesity. Thus, disrupting GIP signaling represents a promising novel therapeutic strategy for the treatment of obesity. METHODOLOGY/PRINCIPAL FINDINGS: In order to block GIP signaling we chose an active vaccination approach using GIP peptides covalently attached to virus-like particles (VLP-GIP). Vaccination of mice with VLP-GIP induced high titers of specific antibodies and efficiently reduced body weight gain in animals fed a high fat diet. The reduction in body weight gain could be attributed to reduced accumulation of fat. Moreover, increased weight loss was observed in obese mice vaccinated with VLP-GIP. Importantly, despite the incretin action of GIP, VLP-GIP-treated mice did not show signs of glucose intolerance. CONCLUSIONS/SIGNIFICANCE: This study shows that vaccination against GIP was safe and effective. Thus active vaccination may represent a novel, long-lasting treatment for obesity. However further preclinical safety/toxicology studies will be required before the therapeutic concept can be addressed in humans

Norms of Presentational Force

This is the author's accepted manuscript, made available with permission of the American Forensic Association.Can style or presentational devices reasonably compel us to believe, agree, act? I submit that they can, and that the normative pragmatic project explains how. After describing a normative pragmatic approach to presentational force, I analyze and evaluate presentational force in Susan B. Anthony's "Is it a Crime for a U. S. Citizen to Vote" as it apparently proceeds from logic, emotion, and style. I conclude with reflections on the compatibility of the normative pragmatic approach with the recently-developed pragma-dialectical treatment of presentational devices

Opportunistic infections in immunosuppressed patients with juvenile idiopathic arthritis: Analysis by the Pharmachild Safety Adjudication Committee

Background: To derive a list of opportunistic infections (OI) through the analysis of the juvenile idiopathic arthritis (JIA) patients in the Pharmachild registry by an independent Safety Adjudication Committee (SAC). Methods: The SAC (3 pediatric rheumatologists and 2 pediatric infectious disease specialists) elaborated and approved by consensus a provisional list of OI for use in JIA. Through a 5 step-procedure, all the severe and serious infections, classified as per MedDRA dictionary and retrieved in the Pharmachild registry, were evaluated by the SAC by answering six questions and adjudicated with the agreement of 3/5 specialists. A final evidence-based list of OI resulted by matching the adjudicated infections with the provisional list of OI. Results: A total of 772 infectious events in 572 eligible patients, of which 335 serious/severe/very severe non-OI and 437 OI (any intensity/severity), according to the provisional list, were retrieved. Six hundred eighty-two of 772 (88.3%) were adjudicated as infections, of them 603/682 (88.4%) as common and 119/682 (17.4%) as OI by the SAC. Matching these 119 opportunistic events with the provisional list, 106 were confirmed by the SAC as OI, and among them infections by herpes viruses were the most frequent (68%), followed by tuberculosis (27.4%). The remaining events were divided in the groups of non-OI and possible/patient and/or pathogen-related OI. Conclusions: We found a significant number of OI in JIA patients on immunosuppressive therapy. The proposed list of OI, created by consensus and validated in the Pharmachild cohort, could facilitate comparison among future pharmacovigilance studies. Trial registration: Clinicaltrials.gov NCT 01399281; ENCePP seal: awarded on 25 November 2011

Pioneer personal history, Alma Lutz

Typescript of a biographical sketch of Alma Lutz, from an interview. He was born in Pennsylvania in 1841, and his family moved to Nauvoo and were at Winter Quarters before crossing the plains to Utah. He lived at Smithfield, Randolph, Moab, and Provo. Typed by Arnel Holyoak of Moab in 193

Dendritic Cell Subset Distributions in the Aorta in Healthy and Atherosclerotic Mice

Dendritic cells (DCs) can be sub-divided into various subsets that play specialized roles in priming of adaptive immune responses. Atherosclerosis is regarded as a chronic inflammatory disease of the vessel wall and DCs can be found in non-inflamed and diseased arteries. We here performed a systematic analyses of DCs subsets during atherogenesis. Our data indicate that distinct DC subsets can be localized in the vessel wall. In C57BL/6 and low density lipoprotein receptor-deficient (Ldlr−/−) mice, CD11c+ MHCII+ DCs could be discriminated into CD103− CD11b+F4/80+, CD11b+F4/80− and CD11b−F4/80− DCs and CD103+ CD11b−F4/80− DCs. Except for CD103− CD11b− F4/80− DCs, these subsets expanded in high fat diet-fed Ldlr−/− mice. Signal-regulatory protein (Sirp)-α was detected on aortic macrophages, CD11b+ DCs, and partially on CD103− CD11b− F4/80− but not on CD103+ DCs. Notably, in FMS-like tyrosine kinase 3-ligand-deficient (Flt3l−/−) mice, a specific loss of CD103+ DCs but also CD103− CD11b+ F4/80− DCs was evidenced. Aortic CD103+ and CD11b+ F4/80− CD103− DCs may thus belong to conventional rather than monocyte-derived DCs, given their dependence on Flt3L-signalling. CD64, postulated to distinguish macrophages from DCs, could not be detected on DC subsets under physiological conditions, but appeared in a fraction of CD103− CD11b+ F4/80− and CD11b+ F4/80+ cells in atherosclerotic Ldlr−/− mice. The emergence of CD64 expression in atherosclerosis may indicate that CD11b+ F4/80− DCs similar to CD11b+ F4/80+ DCs are at least in part derived from immigrated monocytes during atherosclerotic lesion formation. Our data advance our knowledge about the presence of distinct DC subsets and their accumulation characteristics in atherosclerosis, and may help to assist in future studies aiming at specific DC-based therapeutic strategies for the treatment of chronic vascular inflammation

Identification of DC subsets in the aorta.

<p>Representative FACS plots for identification of DC subsets in healthy, chow-fed <i>Ldlr</i>^−/− mice. After exclusion of TCRβ⁺/CD19⁺ T and B cells, CD11c⁺ MHCII⁺ DCs were further subdivided into CD103⁺ and CD103⁻ DCs. CD103⁺ DCs do not express CD11b or F4/80 while CD103⁻ DCs were further subdivided into CD11b⁺ F4/80⁻, CD11b⁺ F4/80⁺ and CD11b⁻F4/80⁻ DCs. Macrophages were defined as CD11c⁻ MHCII⁺ CD11b⁺ F4/80⁺. Representative contour plots from 6–9 mice per group are shown.</p

Localization of CD11c⁺ cells in the aortic root.

<p>(A) Aortic root sections of healthy and atherosclerotic <i>apoE</i>^−/−CD11c-YFP mice (arrow heads indicate CD11c⁺ cells, green). Nuclei are counterstained with DAPI (blue; scale bars, 50 µm).</p

Characterization of aortic DC subsets.

<p>Representative co-immunofluorescence staining of aortic root sections of <i>Ldlr</i>^−/− mice fed a high fat diet for 12 weeks, revealing cells showing staining for only CD11c (red, filled arrow heads) or F4/80⁺ (green, narrow arrows) as well as both CD11c and F4/80 (yellow, bold arrows). Nuclei are counterstained with DAPI (blue). Oil-red-O staining (red) for lipids in adjacent sections. Scale bars, 50 µm.</p

CD64 expression on aortic DC subsets and macrophages.

<p>Representative histograms of CD64 expression on aortic DC subsets and macrophages. Representative histograms from 6–9 mice per group are shown.</p