Long-lasting antidiabetic effect of a dipeptidyl peptidase IV-resistant analog of glucagon-like peptide-1.

Glucagon-like peptide-1(7-37) (GLP-1) is the most potent insulinotropic hormone characterized thus far. Because its activity is preserved in non-insulin-dependent diabetes mellitus (NIDDM) patients, it is considered a potential new drug for the treatment of this disease. One limitation in its therapeutic use is a short half-life in vivo (5 minutes), due in part to a fast degradation by the endoprotease dipeptidylpeptidase IV (DPPIV). Recently, it was reported that GLP-1 became resistant to DPPIV when the alanine residue at position 8 was replaced by a glycine (GLP-1-Gly8). We report here that this change slightly decreased the affinity of the peptide for its receptor (IC50, 0.41 +/- 0.14 and 1.39 +/- 0.61 nmol/L for GLP-1 and GLP-1-Gly8, respectively) but did not change the efficiency to stimulate accumulation of intracellular cyclic adenosine monophosphate (cAMP) (EC50, 0.25 +/- 0.05 and 0.36 +/- 0.06 nmol/L for GLP-1 and GLP-1-Gly8, respectively). Second, we demonstrate for the first time that this mutant has an improved insulinotropic activity compared with the wild-type peptide when tested in vivo in an animal model of diabetes. A single injection of 0.1 nmol GLP-1-Gly8 in diabetic mice fed a high-fat diet can correct fasting hyperglycemia and glucose intolerance for several hours, whereas the activity of 1 nmol GLP-1 vanishes a few minutes after injection. These actions were correlated with increased insulin and decreased glucagon levels. Interestingly, normoglycemia was maintained over a period that was longer than the predicted peptide half-life, suggesting a yet undescribed long-term effect of GLP-1-Gly8. GLP-1-Gly8 thus has a markedly improved therapeutic potential compared with GLP-1, since it can be used at much lower doses and with a more flexible schedule of administration.

Le principe de transparence dans le canton de Vaud : évaluation des chapitres I, III, IV et VI de la Loi du 24 septembre 2002 sur l'information

La Loi vaudoise sur l'information (LInfo), en vigueur depuis le 1er septembre 2003, contient les bases légales relatives à l'information communiquée par l'Etat aux médias et au public. A l'image de plus en plus de législations en la matière, elle consacre le principe de l'information sur demande, selon lequel tout individu a désormais le droit de consulter des documents officiels et d'obtenir de l'information de la part des autorités sans devoir motiver sa demande. La présente évaluation s'intéresse à comprendre comment ce principe de transparence est défini dans cette loi, quelle est son application par l'administration, dans quelle mesure il est utilisé par les citoyens et enfin quels sont ses effets six ans après son entrée en vigueur. Das waadtländische Informationsgesetz (LInfo), in Kraft seit dem 1. September 2003, liefert die rechtliche Grundlage betreffend Informationen die durch den Kanton an die Medien und die Öffentlichkeit kommuniziert werden. Als Grundlage dient dazu das Prinzip um Erhalt von Informationen, nach welchem jede Person das Recht hat offizielle Dokumente einzusehen und Informationen von den Behörden zu erhalten ohne die Anfrage begründen zu müssen. Der vorliegende Beitrag hinterfragt wie dieses Transparenzprinzip im Gesetz definiert ist und wie es durch die Verwaltung angewendet wird. Weiter wird untersucht in welchem Ausmass es durch die Bürger und Bürgerinnen angewendet wird und was das Gesetz sechs Jahre nach seinem Inkrafttreten bewirkt hat.

IV thrombolysis and statins.

Objective: To examine whether prior statin use affects outcome and intracranial hemorrhage (ICH) rates in stroke patients receiving IV thrombolysis (IVT).Methods: In a pooled observational study of 11 IVT databases, we compared outcomes between statin users and nonusers. Outcome measures were excellent 3-month outcome (modified Rankin scale 0-1) and ICH in 3 categories. We distinguished all ICHs (ICH(all)), symptomatic ICH based on the criteria of the ECASS-II trial (SICH(ECASS-II)), and symptomatic ICH based on the criteria of the National Institute of Neurological Disorders and Stroke (NINDS) trial (SICH(NINDS)). Unadjusted and adjusted odds ratios (OR) with 95% confidence intervals were calculated.Results: Among 4,012 IVT-treated patients, 918 (22.9%) were statin users. They were older, more often male, and more frequently had hypertension, hypercholesterolemia, diabetes, coronary heart disease, and concomitant antithrombotic use compared with nonusers. Fewer statin users (35.5%) than nonusers (39.7%) reached an excellent 3-month outcome (OR(unadjusted) 0.84 [0.72-0.98], p = 0.02). After adjustment for age, gender, blood pressure, time to thrombolysis, and stroke severity, the association was no longer significant (0.89 [0.74-1.06], p = 0.20). ICH occurred by trend more often in statin users (ICH(all) 20.1% vs 17.4%; SICH(NINDS) 9.2% vs 7.5%; SICH(ECASS-II) 6.9% vs 5.1%). This difference was statistically significant only for SICH(ECASS-II) (OR = 1.38 [1.02-1.87]). After adjustment for age, gender, blood pressure, use of antithrombotics, and stroke severity, the OR(adjusted) for each category of ICH (ICH(all) 1.15 [0.93-1.41]; SICH(ECASS-II) 1.32 [0.94-1.85]; SICH(NINDS) 1.16 [0.87-1.56]) showed no difference between statin users and nonusers.Conclusion: In stroke patients receiving IVT, prior statin use was neither an independent predictor of functional outcome nor ICH. It may be considered as an indicator of baseline characteristics that are associated with a less favorable course. Neurology (R) 2011;77:888-895

Cellular delivery of pyrenyl-arene ruthenium complexes by a water-soluble arene ruthenium metalla-cage.

Three pyrenyl-arene ruthenium complexes (M(1)-M(3)) of the general formula [Ru(η(6)-arene-pyrenyl)Cl(2)(pta)] (pta = 1,3,5-triaza-7-phosphaadamantane) have been synthesised and characterised. Prior to the coordination to ruthenium, pyrene was connected to the arene ligand via an alkane chain containing different functional groups: ester (L(1)), ether (L(2)) and amide (L(3)), respectively. Furthermore, the pyrenyl moieties of the M(n) complexes were encapsulated within the hydrophobic cavity of the water soluble metalla-cage, [Ru(6)(η(6)-p-cymene)(6)(tpt)(2)(donq)(3)](6+) (tpt = 2,4,6-tri-(pyridin-4-yl)-1,3,5-triazine; donq = 5,8-dioxydo-1,4-naphthoquinonato), while the arene ruthenium end was pointing out of the cage, thus giving rise to the corresponding host-guest systems [M(n)⊂Ru(6)(η(6)-p-cymene)(6)(tpt)(2)(donq)(3)](6+) ([M(n)⊂cage](6+)). The antitumor activity of the pyrenyl-arene ruthenium complexes (M(n)) and the corresponding host-guest systems [M(n)⊂cage][CF(3)SO(3)](6) were evaluated in vitro in different types of human cancer cell lines (A549, A2780, A2780cisR, Me300 and HeLa). Complex M(2), which contains an ether group within the alkane chain, demonstrated at least a 10 times higher cytotoxicity than the reference compound [Ru(η(6)-p-cymene)Cl(2)(pta)] (RAPTA-C). All host-guest systems [M(n)⊂cage](6+) showed good anticancer activity with IC(50) values ranging from 2 to 8 μM after 72 h exposure. The fluorescence of the pyrenyl moiety allowed the monitoring of the cellular uptake and revealed an increase of uptake by a factor two of the M(2) complex when encapsulated in the metalla-cage [Ru(6)(η(6)-p-cymene)(6)(tpt)(2)(donq)(3)](6+).

Influence of the diketonato ligand on the cytotoxicities of [Ru(eta(6)-p-cymene)-(R(2)acac)(PTA)](+) complexes (PTA=1,3,5-triaza-7-phosphaadamantane)

A series of compounds of general formula [Ru(eta(6)-p-cymene) (R(2)acac)(PTA)][X] (R(2)acac = Me(2)acac, tBu(2)acac, Ph(2)acac, Me(2)acac-Cl; PTA = 1,3,5-triaza-7-phosphaadamantane; X = BPh4, BF4), and the precursor to the Me2acac-Cl derivative [Ru(eta(6)-p-cymene)(Me(2)acac-Cl)Cl], have been prepared and characterised spectroscopically. Five of the compounds have also been characterised in the solid state by X-ray crystallography. The tetrafluoroborate salts are water-soluble, quite resistant to hydrolysis, and have been evaluated for cytotoxicity against A549 lung carcinoma and A2780 human ovarian cancer cells. The compounds are cytotoxic towards the latter cell line, and relative activities are discussed in terms of hydrolysis (less important) and lipophilicity, which appears to exert the dominating influence.

Soluble MHC-peptide complexes: tools for the monitoring of T cell responses in clinical trials and basic research.

Soluble MHC-peptide complexes, commonly known as tetramers, allow the detection and isolation of antigen-specific T cells. Although other types of soluble MHC-peptide complexes have been introduced, the most commonly used MHC class I staining reagents are those originally described by Altman and Davis. As these reagents have become an essential tool for T cell analysis, it is important to have a large repertoire of such reagents to cover a broad range of applications in cancer research and clinical trials. Our tetramer collection currently comprises 228 human and 60 mouse tetramers and new reagents are continuously being added. For the MHC II tetramers, the list currently contains 21 human (HLA-DR, DQ and DP) and 5 mouse (I-A(b)) tetramers. Quantitative enumeration of antigen-specific T cells by tetramer staining, especially at low frequencies, critically depends on the quality of the tetramers and on the staining procedures. For conclusive longitudinal monitoring, standardized reagents and analysis protocols need to be used. This is especially true for the monitoring of antigen-specific CD4+ T cells, as there are large variations in the quality of MHC II tetramers and staining conditions. This commentary provides an overview of our tetramer collection and indications on how tetramers should be used to obtain optimal results.

IL-7/anti-IL-7 mAb complexes restore T cell development and induce homeostatic T Cell expansion without lymphopenia.

IL-7, a member of the common gamma-chain family of cytokines, is essential for B and T lymphocyte development and homeostasis of mature T cell subsets. Thus, naive and memory T cells are both dependent on IL-7 for survival and homeostatic proliferation under lymphopenic conditions. In line with prior findings with IL-2, we show in this study that the biological activity of IL-7 in vivo is greatly increased by association with anti-IL-7 mAb. Under in vivo conditions, IL-7/mAb complexes displayed 50- to 100-fold higher activity than free IL-7 and induced massive expansion of pre-B cells. IL-7/mAb complexes also increased thymopoiesis in normal mice and restored thymopoeisis in IL-7-deficient mice. For mature T cells, IL-7/mAb complexes induced marked homeostatic proliferation of both naive and memory CD4(+) and CD8(+) cell subsets even under normal T cell-replete conditions. Finally, IL-7/mAb complexes were able to enhance the magnitude of the primary response of Ag-specific naive CD8(+) cells. The strong stimulatory activity of IL-7/mAb complexes could be useful for treatment of immunodeficiency and cancer.

Calmodulin kinase IV: expression and function during rat brain development.

The expression of calmodulin kinase IV (CaMKIV) can be induced by the thyroid hormone T3 in a time- and concentration-dependent manner at a very early stage of brain differentiation using a fetal rat telencephalon primary cell culture system which can grow and differentiate under chemically defined conditions (Krebs et al. (1996) J. Biol. Chem. 271, 11055-11058). After the induction of CaMKIV by T3 we examined the influence of prolonged absence of T3 from the culture medium on the expression of CaMKIV. We could demonstrate that after the T3-dependent induction of CaMKIV, omission of the hormone, even for 8 days, from the medium did not downregulate the expression of CaMKIV indicating that different regulatory mechanisms became important for the expression of the enzyme. We further showed that CaMKIV could be involved in the Ca(2+) -dependent expression of the immediate early gene c-fos, probably via phosphorylation of the transcription factor CREB. Convergence of signal transduction pathways on this transcription factor by using different protein kinases may explain the importance of CREB for the regulation of different cellular processes.

Anévrismes complexes de l'aorte abdominale: la chirurgie ouverte est-elle obsolète [The complex aortic abdominal aneurysm: is open surgery old fashion?].

Open surgery is still the main treatment of complex abdominal aortic aneurysm. Nevertheless, this approach is associated with major complications and high mortality rate. Therefore the fenestrated endograft has been used to treat the juxtarenal aneurysms. Unfortunately, no randomised controlled study is available to assess the efficacy of such devices. Moreover, the costs are still prohibitive to generalise this approach. Alternative treatments such as chimney or sandwich technique are being evaluated in order to avoid theses disadvantages. The aim of this paper is to present the endovascular approach to treat juxtarenal aneurysm and to emphasize that this option should be used only by highly specialized vascular centres.

Crystal structures of two closely related but antigenically distinct HLA-A2/melanocyte-melanoma tumor-antigen peptide complexes.

We have determined high-resolution crystal structures of the complexes of HLA-A2 molecules with two modified immunodominant peptides from the melanoma tumor-associated protein Melan-A/Melanoma Ag recognized by T cells-1. The two peptides, a decamer and nonamer with overlapping sequences (ELAGIGILTV and ALGIGILTV), are modified in the second residue to increase their affinity for HLA-A2. The modified decamer is more immunogenic than the natural peptide and a candidate for peptide-based melanoma immunotherapy. The crystal structures at 1.8 and 2.15 A resolution define the differences in binding modes of the modified peptides, including different clusters of water molecules that appear to stabilize the peptide-HLA interaction. The structures suggest both how the wild-type peptides would bind and how three categories of cytotoxic T lymphocytes with differing fine specificity might recognize the two peptides.

Treatment of osteitis pubis with on single iv injection of Ibandronate: report of two cases

Objectives: Osteitis pubis is a noninfectious painfulinflammatory disorder of the symphysis pubis. Etiologicfactors are numerous, the most common are: osseousextension of adductor enthesis due to sport overuse,irritation after urological and abdominal procedures, andsystemic inflammatory disorders in particular spondylarthropathies.Many cases are idiopathic. The symptomsconsist of regional chronic mechanical and sometimenocturnal pain. Diagnosis is usually confirmed by eitherbone scintigraphy or by MRI. There are no standardtreatments but conservative approaches including rest andNSAIDS are generally recommended. In 2001, a goodclinical and radiological response of three refractory caseswith 3-6 monthly perfusions of pamidronate was reported(1). Ibandronate is a much more powerful and long-lastingbisphosphonate than pamidronate, and has not yet beenreported in literature to our knowledge in this indication.Materials/Methods: We present two cases of idiopathicorigin: one woman (63 years old) and one man (36 yearsold).The symptoms were present >3 months in the firstpatient and 1 year in the second. The diagnosis wasconfirmed by MRI which showed bone edema on bothsizes of symphysis and in the second case bony erosionsadjacent to the joint were seen. Both cases failed to respondto conservative measures. Both patients received one singledirect iv Injection of 3 mg of Ibandronate.Results: The injections resulted in a rapid (within a fewdays) resolution of pain that lasted more than 6 months inboth patients. No side effects were observed. In the firstcase, an isotope bone scan performed 4 months after theinjection showed no residual uptake. The second patienthad a repeated MRI after 6 months. It demonstrated anattenuation of bone edema compared to the first MRI.Conclusions: IV Ibandronate may constitute a safe andeffective treatment option for patients with refractoryosteitis pubis.Reference: 1: Maksymowych WP, Aaron SL, Russell AS, JRheumatol 28:2754, 2001.Disclosure of Interest: None declared.

Regulation of the transforming growth factor beta-responsive transcription factor CTF-1 by calcineurin and calcium/calmodulin-dependent protein kinase IV.

Transforming growth factor beta (TGF-beta) is a pluripotent peptide hormone that regulates various cellular activities, including growth, differentiation, and extracellular matrix protein gene expression. We previously showed that TGF-beta induces the transcriptional activation domain (TAD) of CTF-1, the prototypic member of the CTF/NF-I family of transcription factors. This induction correlates with the proposed role of CTF/NF-I binding sites in collagen gene induction by TGF-beta. However, the mechanisms of TGF-beta signal transduction remain poorly understood. Here, we analyzed the role of free calcium signaling in the induction of CTF-1 transcriptional activity by TGF-beta. We found that TGF-beta stimulates calcium influx and mediates an increase of the cytoplasmic calcium concentration in NIH3T3 cells. TGF-beta induction of CTF-1 is inhibited in cells pretreated with thapsigargin, which depletes the endoplasmic reticulum calcium stores, thus further arguing for the potential relevance of calcium mobilization in TGF-beta action. Consistent with this possibility, expression of a constitutively active form of the calcium/calmodulin-dependent phosphatase calcineurin or of the calcium/calmodulin-dependent kinase IV (DeltaCaMKIV) specifically induces the CTF-1 TAD and the endogenous mouse CTF/NF-I proteins. Both calcineurin- and DeltaCaMKIV-mediated induction require the previously identified TGF-beta-responsive domain of CTF-1. The immunosuppressants cyclosporin A and FK506 abolish calcineurin-mediated induction of CTF-1 activity. However, TGF-beta still induces the CTF-1 TAD in cells treated with these compounds or in cells overexpressing both calcineurin and DeltaCaMKIV, suggesting that other calcium-sensitive enzymes might mediate TGF-beta action. These results identify CTF/NF-I as a novel calcium signaling pathway-responsive transcription factor and further suggest multiple molecular mechanisms for the induction of CTF/NF-I transcriptional activity by growth factors.

Taxometric analysis of DSM-IV and DSM-5 alcohol use disorders.

BACKGROUND: With preparations currently being made for the Diagnostic and Statistical Manual of Mental Disorders-5th Edition (DSM-5), one prominent issue to resolve is whether alcohol use disorders are better represented as discrete categorical entities or as a dimensional construct. The purpose of this study was to investigate the latent structure of DSM-4th edition (DSM-IV) and proposed DSM-5 alcohol use disorders. METHODS: The study used the Wave 2 National Epidemiologic Survey on Alcohol and Related Conditions (NESARC) to conduct taxometric analyses of DSM-IV and DSM-5 alcohol use disorders defined by different thresholds to determine the taxonic or dimensional structure underlying the disorders. RESULTS: DSM-IV and DSM-5 alcohol abuse and dependence criteria with 3+ thresholds demonstrated a dimensional structure. Corresponding thresholds with 4+ criteria were clearly taxonic, as were thresholds defined by cut-offs of 5+ and 6+ criteria. CONCLUSIONS: DSM-IV and DSM-5 alcohol use disorders demonstrated a hybrid taxonic-dimensional structure. That is, DSM-IV and DSM-5 alcohol use disorders may be taxonically distinct compared to no disorder if defined by a threshold of 4 or more criteria. However, there may be dimensional variation remaining among non-problematic to subclinical cases. A careful and systematic program of structural research using taxometric and psychometric procedures is warranted.

Structure and function of RecA-DNA complexes.

While the E. coli RecA protein has been the most intensively studied enzyme of homologous recombination, the unusual RecA-DNA filament has stood alone until very recently. It now appears that this protein is part of a universal family that spans all of biology, and the filament that is formed by the protein on DNA is a universal structure. With RecA's role in recombination given new and greatly increased significance, we focus in this review on the energetics of the RecA-mediated strand exchange and the relation between the energetics and recombination spanning heterologous inserts.