Characterization of a fully active N-terminal 37-kDa polypeptide obtained by limited tryptic cleavage of pig kidney D-amino acid oxidase.

In order to obtain further information on the structure of D-amino acid oxidase (EC 1.4.3.3), limited proteolysis experiments have been carried out on its apo-, holo-, and holoenzyme-benzoate forms. The enzyme is unsensitive to 10% (w/w) chymotrypsin, while incubation with 10% (w/w) trypsin, under nondenaturating conditions, produces inactivation and proteolysis patterns which are different for the three forms of enzyme analyzed. These results confirm the previously reported conformational changes which occur upon binding of coenzyme to the apoprotein, and of benzoate to holoenzyme. The stable 37.0-kDa polypeptide, obtained from the apo- and holoenzyme-benzoate complex upon cleavage of a C-terminal 2.0-kDa fragment, retains full catalytic activity with unaltered kinetic parameters, and the coenzyme binding properties of the native enzyme. These results are in agreement with the tentative localization of the FAD-binding domain in the N-terminal region of the enzyme, and with the hypothesis that the function of the C-terminal region of D-amino acid oxidase could be related to the import of the enzyme into the peroxisomes, as suggested by Gould et al. (Gould, S. J., Keller, G. A., and Subramani, S. (1988) J. Cell. Biol. 107, 897-905)

The primary structure of the flavoprotein D-aspartate oxidase from beef kidney.

The complete primary structure of the peroxisomal flavoenzyme D-aspartate oxidase from beef kidney has been determined by analyses of the peptides obtained through fragmentation of the carboxymethylated protein with trypsin, CNBr, heptafluorobutyric acid/CNBr and Staphylococcus aureus V8 protease. The protein consists of a single polypeptide of 338 residues, accounting for a M(r) of 37,305 for the apoprotein. A form of the enzyme lacking Lys-338 and therefore ending with Pro-337 has been detected. The N-terminal residue is blocked. Seven cysteines and no disulfide bridges are present. Residue 228 can be either Ile or Val. Thus, D-aspartate oxidase presents two types of heterogeneity in the polypeptide chain in addition to the one already described concerning the possible content of FAD or 6-hydroxyflavin adenine dinucleotide. Comparison of the primary structure of D-aspartate oxidase with other known sequences reveals that D-aspartate oxidase is homologous with D-amino acid oxidase (another flavo-oxidase) and does not present significant sequence similarities with any other protein, including flavoenzymes

The Global Health Watch

Why three non-governmental organizations are launching an alternative to the World Health Repor

Conversion of nanoscale topographical information of cluster-assembled zirconia surfaces into mechanotransductive events promotes neuronal differentiation

Additional file 4: Table S1. Proteomic data for upregulated proteins. Proteins upregulated (compared to flat-Zr) or present only in cells grown on ns-Zr15. Adhesome proteins and proteins with roles in mechanobiological processes are marked in dark and light grey, respectively

Guidelines for the diagnosis, prevention and treatment of osteoporosis, 2012

La osteoporosis es una patología en constante crecimiento y que afecta a más de 200 millones de personas a nivel mundial. Las recomendaciones presentes son guías para el diagnóstico, la prevención y tratamiento pero no normas para las decisiones clínicas en pacientes individuales. El médico debe adaptarlas a situaciones y pacientes deferentes, incorporando factores personales que trascienden los límites de estas guías y hacen al saber y al arte del médico. Como todo conocimiento médico científico deben ser revisadas y actualizadas periódicamente a medida que se adquieran nuevas, mejores y más efectivas herramientas diagnósticas y terapéuticas.Osteoporosis is a constantly growing disease which affects over 200 million people worldwide. The present recommendations are guidelines for its diagnosis, prevention and treatment, but they do not constitute standards for clinical decisions in individual patients. The physician must adapt them to individual patients and special situations, incorporating personal factors that transcend the limits of these guidelines and are dependent on the knowledge and art of the physician. These guidelines should be reviewed and updated periodically as new, better and more effective diagnostic and therapeutic tools become available.Fil: Schurman, Leon. Grupo de Investigación en Osteopatías y Metabolismo Mineral; ArgentinaFil: Bagur, Alicia. Centro de Osteopatías Médicas; ArgentinaFil: Claus Hermberg, Heraldo. Hospital Alemán; ArgentinaFil: Messina, Osvaldo D.. Ministerio de Defensa. Ejercito Argentino. Hospital Militar Central Cirujano Mayor "Cosme Argerich"; ArgentinaFil: Negri, Armando L.. Universidad del Salvador; ArgentinaFil: Sánchez, Ariel. Centro de Endocrinología; ArgentinaFil: González, Claudio. Centro de Educación Médica e Investigaciones Clínicas; ArgentinaFil: Diehl, María. Hospital Italiano de Buenos Aires; ArgentinaFil: Rey, Paula. Universidad del Salvador; ArgentinaFil: Gamba, Julieta. Ministerio de Defensa. Ejercito Argentino. Hospital Militar Central Cirujano Mayor "Cosme Argerich"; ArgentinaFil: Chiarpenello, Javier. Universidad Nacional de Rosario; ArgentinaFil: Moggia, María Susana. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; ArgentinaFil: Mastaglia, Silvina Rosana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Inmunología, Genética y Metabolismo; Argentin

Proteomic dissection of nanotopography-sensitive mechanotransductive signaling hubs that foster neuronal differentiation in PC12 cells

Neuronal cells are competent in precisely sensing nanotopographical features of their microenvironment. The perceived microenvironmental information will be “interpreted” by mechanotransductive processes and impacts on neuronal functioning and differentiation. Attempts to influence neuronal differentiation by engineering substrates that mimic appropriate extracellular matrix (ECM) topographies are hampered by the fact that profound details of mechanosensing/-transduction complexity remain elusive. Introducing omics methods into these biomaterial approaches has the potential to provide a deeper insight into the molecular processes and signaling cascades underlying mechanosensing/-transduction but their exigence in cellular material is often opposed by technical limitations of major substrate top-down fabrication methods. Supersonic cluster beam deposition (SCBD) allows instead the bottom-up fabrication of nanostructured substrates over large areas characterized by a quantitatively controllable ECM-like nanoroughness that has been recently shown to foster neuron differentiation and maturation. Exploiting this capacity of SCBD, we challenged mechanosensing/-transduction and differentiative behavior of neuron-like PC12 cells with diverse nanotopographies and/or changes of their biomechanical status, and analyzed their phosphoproteomic profiles in these settings. Versatile proteins that can be associated to significant processes along the mechanotransductive signal sequence, i.e., cell/cell interaction, glycocalyx and ECM, membrane/f-actin linkage and integrin activation, cell/substrate interaction, integrin adhesion complex, actomyosin organization/cellular mechanics, nuclear organization, and transcriptional regulation, were affected. The phosphoproteomic data suggested furthermore an involvement of ILK, mTOR, Wnt, and calciumsignaling in these nanotopography- and/or cell mechanics-related processes. Altogether, potential nanotopography-sensitive mechanotransductive signaling hubs participating in neuronal differentiation were dissected

Nitric oxide synthase mediates PC12 differentiation induced by the surface topography of nanostructured TiO2

Background: Substrate nanoscale topography influences cell proliferation and differentiation through mechanisms that are at present poorly understood. In particular the molecular mechanism through which cells 'sense' and adapt to the substrate and activate specific intracellular signals, influencing cells survival and behavior, remains to be clarified. Results: To characterize these processes at the molecular level we studied the differentiation of PC12 cells on nanostructured TiO2 films obtained by supersonic cluster beam deposition. Our findings indicate that, in PC12 cells grown without Nerve Growth Factor (NGF), the roughness of nanostructured TiO2 triggers neuritogenesis by activating the expression of nitric oxide synthase (NOS) and the phospho-extracellular signal-regulated kinase 1/2 (pERK1/2) signaling. Differentiation is associated with an increase in protein nitration as observed in PC12 cells grown on flat surfaces in the presence of NGF. We demonstrate that cell differentiation and protein nitration induced by topography are not specific for PC12 cells but can be regarded as generalized effects produced by the substrate on different neuronal-like cell types, as shown by growing the human neuroblastoma SH-SY5Y cell line on nanostructured TiO2. Conclusion: Our data provide the evidence that the nitric oxide (NO) signal cascade is involved in the differentiation process induced by nanotopography, adding new information on the mechanism and proteins involved in the neuritogenesis triggered by the surface properties

Reflexiones en salud pública

Desde una visión general y práctica este texto facilita la reflexión sobre tópicos de interés para la salud pública. Con un lenguaje sencillo, busca aproximarse al estudio de la salud desde una visión interdisciplinar, partiendo del reconocimiento del rol que le compete al individuo, la sociedad y el Estado. El objetivo general es promover en el lector el análisis crítico de problemáticas relacionadas con el ámbito de la salud pública, constituyéndose en una iniciativa para el posterior desarrollo de acciones en el área

Pleuroparenchymal fibroelastosis in systemic sclerosis: prevalence and prognostic impact

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