Psychometric properties of the Clarke questionnaire for hypoglycemia awareness in the Spanish population with type 2 diabetes

Objectives: The Clarke questionnaire, validated in Spanish language, assesses hypoglycemia awareness in patients with type 1 diabetes. This study aimed to analyze its psychometric properties in patients with type 2 diabetes (T2DM). Methods: This was a questionnaire validation study. Patients with T2DM and treated with insulin, sulfonylureas or glinides were consecutively recruited from six endocrinology consultations and six primary care centers. The internal structure of the 8-item Clarke questionnaire was analyzed by exploratory (training sample) and confirmatory (testing sample) factor analysis; the internal consistency using Omega’s McDonald coefficient; and goodness of fit with comparative fit index (CFI, cutoff >0.9), Goodness of Fit Index (GFI, cutoff >0.9), and root mean-square error of approximation (RMSEA, cutoff <0.09), as well as unidimensionality indicators. Results: The 265 participants (56.8% men) had a mean age of 67.8 years. Confirmatory factor analysis for one dimension obtained poor indicators: fit test (p < 0.001); CFI = 0.748; RMSEA = 0.122 and SRMR = 0.134. Exploratory factor analysis showed 2 or 3 dimensions with poor adjustment indicators. Omega’s McDonald was 0.739. Conclusions: The Spanish version of the Clarke questionnaire was not valid or reliable for assessing hypoglycemia awareness in people with T2DM in Spanish population

Platinum-Doped Dendritic Structure as a Phosphorescent Label for Bacteria in Two-Photon Excitation Microscopy.

Herein, we present a water-soluble dendritric Pt(II) complex as a phosphorescent label for bacterial cells. The dendritic moiety endows the Pt(II) complex with unique properties such as water solubility, shielding from quenching by dioxygen, and binding to bacterial surfaces. The new biosensor was employed for two-photon excitation microscopy, and the binding was confirmed by electron microscopy, which demonstrates that such hybrid arrays can provide orthogonal yet complementary readouts

Retinoic Acid and VEGF Delay Smooth Muscle Relative to Endothelial Differentiation to Coordinate Inner and Outer Coronary Vessel Wall Morphogenesis

Rationale: Major coronary vessels derive from the proepicardium, the cellular progenitor of the epicardium, coronary endothelium, and coronary smooth muscle cells (CoSMCs). CoSMCs are delayed in their differentiation relative to coronary endothelial cells (CoEs), such that CoSMCs mature only after CoEs have assembled into tubes. The mechanisms underlying this sequential CoE/CoSMC differentiation are unknown. Retinoic acid (RA) is crucial for vascular development and the main RA-synthesizing enzyme is progressively lost from epicardially derived cells as they differentiate into blood vessel types. In parallel, myocardial vascular endothelial growth factor (VEGF) expression also decreases along coronary vessel muscularization. Objective: We hypothesized that RA and VEGF act coordinately as physiological brakes to CoSMC differentiation. Methods and Results: In vitro assays (proepicardial cultures, cocultures, and RALDH2 [retinaldehyde dehydrogenase-2]/VEGF adenoviral overexpression) and in vivo inhibition of RA synthesis show that RA and VEGF act as repressors of CoSMC differentiation, whereas VEGF biases epicardially derived cell differentiation toward the endothelial phenotype. Conclusion: Experiments support a model in which early high levels of RA and VEGF prevent CoSMC differentiation from epicardially derived cells before RA and VEGF levels decline as an extensive endothelial network is established. We suggest this physiological delay guarantees the formation of a complex, hierarchical, tree of coronary vessels. (Circ Res. 2010;107:204-216.)Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)[05/60637-6]Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)[06/50843-0]DGUCoordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES/DGU)[4096/09-6]Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Conselho Nacional de Desenvolvimento Tecnologico (CNPq)[477418/2004-0]Conselho Nacional de Desenvolvimento Tecnologico (CNPq)[305260/2007-3]Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Spanish Ministry of Science and InnovationSpanish Ministry of Innovation and Science[BFU2009-07929]Junta de Andalucia (Spain)Junta de Andalucia[P06-CTS-01614]Spanish cooperative networks on research TERCEL and RECAVA (ISCIII)Spanish cooperative networks on research TERCEL and RECAVA (ISCIII)European UnionEuropean Union[LSHM-CT-2005-018630

A New Versatile Platform for Assessment of Improved Cardiac Performance in Human-Engineered Heart Tissues

Cardiomyocytes derived from human pluripotent stem cells (hPSC-CMs) hold a great potential as human in vitro models for studying heart disease and for drug safety screening. Nevertheless, their associated immaturity relative to the adult myocardium limits their utility in cardiac research. In this study, we describe the development of a platform for generating three-dimensional engineered heart tissues (EHTs) from hPSC-CMs for the measurement of force while under mechanical and electrical stimulation. The modular and versatile EHT platform presented here allows for the formation of three tissues per well in a 12-well plate format, resulting in 36 tissues per plate. We compared the functional performance of EHTs and their histology in three different media and demonstrated that tissues cultured and maintained in maturation medium, containing triiodothyronine (T3), dexamethasone, and insulin-like growth factor-1 (TDI), resulted in a higher force of contraction, sarcomeric organization and alignment, and a higher and lower inotropic response to isoproterenol and nifedipine, respectively. Moreover, in this study, we highlight the importance of integrating a serum-free maturation medium in the EHT platform, making it a suitable tool for cardiovascular research, disease modeling, and preclinical drug testin

Epicardially derived fibroblasts preferentially contribute to the parietal leaflets of the atrioventricular valves in the murine heart

The importance of the epicardium for myocardial and valvuloseptal development has been well established; perturbation of epicardial development results in cardiac abnormalities, including thinning of the ventricular myocardial wall and malformations of the atrioventricular valvuloseptal complex. To determine the spatiotemporal contribution of epicardially derived cells to the developing fibroblast population in the heart, we have used a mWt1/IRES/GFP-Cre mouse to trace the fate of EPDCs from embryonic day (ED)10 until birth. EPDCs begin to populate the compact ventricular myocardium around ED12. The migration of epicardially derived fibroblasts toward the interface between compact and trabecular myocardium is completed around ED14. Remarkably, epicardially derived fibroblasts do not migrate into the trabecular myocardium until after ED17. Migration of EPDCs into the atrioventricular cushion mesenchyme commences around ED12. As development progresses, the number of EPDCs increases significantly, specifically in the leaflets which derive from the lateral atrioventricular cushions. In these developing leaflets the epicardially derived fibroblasts eventually largely replace the endocardially derived cells. Importantly, the contribution of EPDCs to the leaflets derived from the major AV cushions is very limited. The differential contribution of EPDCs to the various leaflets of the atrioventricular valves provides a new paradigm in valve development and could lead to new insights into the pathogenesis of abnormalities that preferentially affect individual components of this region of the heart. The notion that there is a significant difference in the contribution of epicardially and endocardially derived cells to the individual leaflets of the atrioventricular valves has also important pragmatic consequences for the use of endocardial and epicardial cre-mouse models in studies of heart development. (C) 2012 Elsevier Inc. All rights reserve

A novel prohibitin-binding compound induces the mitochondrial apoptotic pathway through NOXA and BIM upregulation

We previously described diaryl trifluorothiazoline compound 1a (hereafter referred to as fluorizoline) as a first-in-class small molecule that induces p53-independent apoptosis in a wide range of tumor cell lines. Fluorizoline directly binds to prohibitin 1 and 2 (PHBs), two proteins involved in the regulation of several cellular processes, including apoptosis. Here we demonstrate that fluorizoline-induced apoptosis is mediated by PHBs, as cells depleted of these proteins are highly resistant to fluorizoline treatment. In addition, BAX and BAK are necessary for fluorizoline-induced cytotoxic effects, thereby proving that apoptosis occurs through the intrinsic pathway. Expression analysis revealed that fluorizoline induced the upregulation of Noxa and Bim mRNA levels, which was not observed in PHB-depleted MEFs. Finally, Noxa(-/-)/ Bim(-/-) MEFs and NOXA-downregulated HeLa cells were resistant to fluorizoline-induced apoptosis. All together, these findings show that fluorizoline requires PHBs to execute the mitochondrial apoptotic pathway