Acid phosphatase and cathepsin D are active expressed enzymes in the placenta of the cat

Enzymes are crucial for the metabolism of macromolecular substrates. In the great majority of cells, most enzymes are constitutive. Nevertheless, inducible enzymes can predominate, determining specialized cell functions. Within this context, histochemistry/immunohistochemistry and biochemistry were used to investigate expression of peroxidase and reduced nicotinamide-adenine dinucleotide phosphate (NADPH)-oxidase, as well as the expression and activity of cathepsin D and acid phosphatase, in trophoblast cells within the endotheliochorial labyrinth and marginal hematoma of the term cat placenta. In the marginal hematoma, elevated Cathepsin D expression and activity was accompanied by erythrophagocytosis. In contrast, acid phosphatase activity was much more intense in the labyrinth, where metabolic exchanges occur. Peroxidase and NAD(P)H-oxidase were predominantly active in trophoblast cells within endosomal vesicles of different placental compartments, indicating that, although reactive oxygen species might participate in endosomal/lysosomal processes, they are not territorially specific or functional markers. These findings highlight differential characteristics of cathepsin D and acid phosphatase activity within each placental compartment, thereby contributing to the comprehension of the territorial role played by the placenta and facilitating future metabolic studies. (C) 2007 Elsevier Ltd. All rights reserved.

Reappraisal of the effective elastic thickness for the sub-Andes using 3-D finite element flexural modelling, gravity and geological constraints

P>Estimates of effective elastic thickness (T(e)) for the western portion of the South American Plate using, independently, forward flexural modelling and coherence analysis, suggest different thermomechanical properties for the same continental lithosphere. We present a review of these T(e) estimates and carry out a critical reappraisal using a common methodology of 3-D finite element method to solve a differential equation for the bending of a thin elastic plate. The finite element flexural model incorporates lateral variations of T(e) and the Andes topography as the load. Three T(e) maps for the entire Andes were analysed: Stewart & Watts (1997), Tassara et al. (2007) and Perez-Gussinye et al. (2007). The predicted flexural deformation obtained for each T(e) map was compared with the depth to the base of the foreland basin sequence. Likewise, the gravity effect of flexurally induced crust-mantle deformation was compared with the observed Bouguer gravity. T(e) estimates using forward flexural modelling by Stewart & Watts (1997) better predict the geological and gravity data for most of the Andean system, particularly in the Central Andes, where T(e) ranges from greater than 70 km in the sub-Andes to less than 15 km under the Andes Cordillera. The misfit between the calculated and observed foreland basin subsidence and the gravity anomaly for the Maranon basin in Peru and the Bermejo basin in Argentina, regardless of the assumed T(e) map, may be due to a dynamic topography component associated with the shallow subduction of the Nazca Plate beneath the Andes at these latitudes.

Sequence and function of lysosomal and digestive cathepsin D-like proteinases of Musca domestica midgut

Musca domestica larvae display in anterior and middle midgut contents, a proteolytic activity with pH optimum of 3.0-3.5 and kinetic properties like cathepsin D. Three cDNAs coding for preprocathepsin D-like proteinases (ppCAD 1, ppCAD 2, ppCAD 3) were cloned from a M. domestica midgut cDNA library. The coded protein sequences included the signal peptide, propeptide and mature enzyme that has all conserved catalytic and substrate binding residues found in bovine lysosomal cathepsin D. Nevertheless, ppCAD 2 and ppCAD 3 lack the characteristic proline loop and glycosylation sites. A comparison among the sequences of cathepsin D-like enzymes from some vertebrates and those found in M. domestica and in the genomes of Aedes aegypti, Drosophila melanogaster, Tribolium castaneum, and Bombyx mori showed that only flies have enzymes lacking the proline loop (as defined by the motif: DxPxPx(G/A)P), thus resembling vertebrate pepsin. ppCAD 3 should correspond to the digestive cathepsin D-like proteinase (CAD) found in enzyme assays because: (1) it seems to be the most expressed CAD, based on the frequency of ESTs found. (2) The mRNA for CAD 3 is expressed only in the anterior and proximal middle midgut. (3) Recombinant procathepsin D-like proteinase (pCAD 3), after auto-activation has a pH optimum of 2.5-3.0 that is close to the luminal pH of M. domestica midgut. (4) Immunoblots of proteins from different tissues revealed with anti-pCAD 3 serum were positive only in samples of anterior and middle midgut tissue and contents. (5) CAD 3 is localized with immunogold inside secretory vesicles and around microvilli in anterior and middle midguit cells. The data support the view that on adapting to deal with a bacteria-rich food in an acid midgut region, M. domestica digestive CAD resulted from the same archetypical gene as the intracellular cathepsin D, paralleling what happened with vertebrates. The lack of the proline loop may be somehow associated with the extracellular role of both pepsin and digestive CAD 3. (C) 2009 Elsevier Ltd. All rights reserved.

Characterisation of anthracyclines from a cosmomycin D-producing species of Streptomyces by collisionally-activated dissociation and ion mobility mass spectrometry

Cultures of cosmomycin D-producing Streptomyces olindensis ICB20 that were propagated for many generations underwent mutations that resulted in production of a range of related anthracyclines by the bacteria. The anthracyclines that retained the two trisaccharide chains of the parent compound were separated by HPLC. Exact mass determination of these compounds revealed that they differed from cosmomycin D (CosD) in that they contained one to three fewer oxygen atoms (loss of hydroxyl groups). Some of the anthracyclines that were separated by HPLC had the same mass. The location from which the hydroxyl groups had been lost relative to CosD (on the aglycone and/or on the sugar residues) was probed by collisionally-activated dissociation using an electrospray ionisation linear quadrupole ion trap mass spectrometer. The presence of anthracyclines with the same mass, but different structure, was confirmed using an electrospray ionisation travelling wave ion mobility mass spectrometer.

Mechanosensitivity of astrocytes on optimized polyacrylamide gels analyzed by quantitative morphometry

Cells are able to detect and respond to mechanical cues from their environment. Previous studies have investigated this mechanosensitivity on various cell types, including neural cells such as astrocytes. In this study, we have carefully optimized polyacrylamide gels, commonly used as compliant growth substrates, considering their homogeneity in surface topography, mechanical properties, and coating density, and identified several potential pitfalls for the purpose of mechanosensitivity studies. The resulting astrocyte response to growth on substrates with shear storage moduli of G` = 100 Pa and G` = 10 kPa was then evaluated as a function of coating density of poly-D-lysine using quantitative morphometric analysis. Astrocytes cultured on stiff substrates showed significantly increased perimeter, area, diameter, elongation, number of extremities and overall complexity if compared to those cultured on compliant substrates. A statistically significant difference in the overall morphological score was confirmed with an artificial intelligence-based shape analysis. The dependence of the cells` morphology on PDL coating density seemed to be weak compared to the effect of the substrate stiffness and was slightly biphasic, with a maximum at 10-100 mu g ml(-1) PDL concentration. Our finding suggests that the compliance of the surrounding tissue in vivo may influence astrocyte morphology and behavior.

Vitamina D e doenças endocrinometabólicas

Atualmente, a insuficiência/deficiência de vitamina D tem sido considerada um problema de saúde pública no mundo todo, em razão de suas implicações no desenvolvimento de diversas doenças, entre elas, o diabetes melito tipo 2 (DMT2), a obesidade e a hipertensão arterial. A deficiência de vitamina D pode predispor à intolerância à glicose, a alterações na secreção de insulina e, assim, ao desenvolvimento do DMT2. Esse possível mecanismo ocorre em razão da presença do receptor de vitamina D em diversas células e tecidos, incluindo células-β do pâncreas, no adipócito e no tecido muscular. Em indivíduos obesos, as alterações do sistema endócrino da vitamina D, caracterizada por elevados níveis de PTH e da 1,25(OH)2D3 são responsáveis pelo feedback negativo da síntese hepática de 25-OHD3 e também pelo maior influxo de cálcio para o meio intracelular, que pode prejudicar a secreção e a sensibilidade à insulina. Na hipertensão, a vitamina D pode atuar via sistema renina-angiotensina e também na função vascular. Há evidências de que a 1,25(OH)2D3 inibe a expressão da renina e bloqueia a proliferação da célula vascular muscular lisa. Entretanto, estudos prospectivos e de intervenção em humanos que comprovem a efetividade da adequação do status da vitamina D sob o aspecto "prevenção e tratamento de doenças endocrinometabólicas" são ainda escassos. Mais pesquisas são necessárias para se garantir o benefício máximo da vitamina D nessas situações.

Metabólitos séricos da vitamina D não se correlacionam com pressão arterial em adolescentes

OBJETIVO: O objetivo deste estudo foi avaliar a associação entre o estado nutricional da vitamina D, a adiposidade e a pressão arterial (PA) em adolescentes. MÉTODOS: Foi realizada avaliação antropométrica, da composição corporal, da ingestão alimentar, de medidas bioquímicas e aferição da PA de 205 adolescentes, com média de idade de 18,2 anos. RESULTADOS: Destes, 12,19% apresentaram PA elevada. O nível sérico médio da 25OHD foi 29,2(0,8) ng/mL, e 62% dos adolescentes apresentaram insuficiência de vitamina D. Não foi encontrada correlação significativa entre a PAS e a PAD com a 25OHD e a 1,25(OH)2D. Houve correlação negativa entre a PAD com os níveis séricos de adiponectina, e tanto a PAS quanto a PAD apresentaram correlação positiva com a circunferência da cintura em ambos os sexos. CONCLUSÃO: Não houve relação entre os níveis séricos de vitamina D e a PA. Porém, a gordura visceral apresenta risco potencial para elevação da PA em adolescentes.

Deficiência em micronutrientes em mudas de sangra d'agua (Croton urucurana, Baill.)

This study had the following objectives: to induce and describe symptoms of deficiency of boron (B), copper (Cu), iron (Fe), manganese (Mn), molybdenum (Mo) and zinc (Zn), determining the effect on the mineral composition of leaves. The experiment was developed in a green house and used diagnosis technique by subtraction. The experimental design usedn was a randomized blocks, with seven treatments and three replicates. It was verified that micronutrient omission led to morphological alterations which, in turn, caused visual symptoms. The symptoms caused by the omission of Cu, Mn and Zn were the first to appear, and were followed by those of B, Fe and Mo. The omission of B, Mn and Zn was responsible for the more pronounced reduction in height and stem diameter.

Cyclooligomerisation of azido-alkyne-functionalised sugars: synthesis of 1,6-linked cyclic pseudo-galactooligosaccharides and assessment of their sialylation by Trypanosoma cruzi trans-sialidase

Cyclic pseudo-galactooligosaccharides were synthesized by cyclooligomerisation of isomeric azido-alkyne derivatives of beta-D-galactopyranose under Cu(I)-catalysed azide-alkyne 1,3-dipolar cycloaddition reaction conditions. The principal products isolated were cyclic dimers and trimers, with lower amounts of cyclic tetramer and pentamer also evident in some cases. Molecular mechanics calculations suggest very compact but flexible structures for the cyclic trimers, with secondary OH groups exposed outside the macrocycle and available for enzymatic glycosylation. The cyclic dimers and trimers represent a new type of acceptor substrate for Trypanosoma cruzi trans-sialidase, giving rise to doubly and triply sialylated glycomacrocycles, respectively.

Variations on a theme: diversification of cuticular hydrocarbons in a clade of cactophilic Drosophila

Background: We characterized variation and chemical composition of epicuticular hydrocarbons (CHCs) in the seven species of the Drosophila buzzatii cluster with gas chromatography/mass spectrometry. Despite the critical role of CHCs in providing resistance to desiccation and involvement in communication, such as courtship behavior, mating, and aggregation, few studies have investigated how CHC profiles evolve within and between species in a phylogenetic context. We analyzed quantitative differences in CHC profiles in populations of the D. buzzatii species cluster in order to assess the concordance of CHC differentiation with species divergence. Results: Thirty-six CHC components were scored in single fly extracts with carbon chain lengths ranging from C(29) to C(39), including methyl-branched alkanes, n alkenes, and alkadienes. Multivariate analysis of variance revealed that CHC amounts were significantly different among all species and canonical discriminant function (CDF) analysis resolved all species into distinct, non-overlapping groups. Significant intraspecific variation was found in different populations of D. serido suggesting that this taxon is comprised of at least two species. We summarized CHC variation using CDF analysis and mapped the first five CHC canonical variates (CVs) onto an independently derived period (per) gene + chromosome inversion + mtDNA COI gene for each sex. We found that the COI sequences were not phylogenetically informative due to introgression between some species, so only per + inversion data were used. Positive phylogenetic signal was observed mainly for CV1 when parsimony methods and the test for serial independence (TFSI) were used. These results changed when no outgroup species were included in the analysis and phylogenetic signal was then observed for female CV3 and/or CV4 and male CV4 and CV5. Finally, removal of divergent populations of D. serido significantly increased the amount of phylogenetic signal as up to four out of five CVs then displayed positive phylogenetic signal. Conclusions: CHCs were conserved among species while quantitative differences in CHC profiles between populations and species were statistically significant. Most CHCs were species-, population-, and sex-specific. Mapping CHCs onto an independently derived phylogeny revealed that a significant portion of CHC variation was explained by species' systematic affinities indicating phylogenetic conservatism in the evolution of these hydrocarbon arrays, presumptive waterproofing compounds and courtship signals as in many other drosophilid species.

Study of the patency of different peritoneal drains used prophylactically in bariatric surgery

AIM: To compare the performance of different types of abdominal drains used in bariatric surgery. METHODS: A vertical banded Roux-en-Y gastric bypass was performed in 33 morbidly obese patients. Drainage of the peritoneal cavity was performed in each case using three different types of drain selected in a randomized manner: a latex tubular drain, a Watterman tubulolaminar drain, and a silicone channeled drain. Drain permeability, contamination of the drained fluid, ease of handling, and patient discomfort were evaluated postoperatively over a period of 7 d. RESULTS: The patients with the silicone channeled drain had larger volumes of drainage compared to patients with tubular and tubulolaminar drains between the third and seventh postoperative days. In addition, a lower incidence of discomfort and of contamination with bacteria of a more pathogenic profile was observed in the patients with the silicone channeled drain. CONCLUSION: The silicone channeled drain was more comfortable and had less chance of occlusion, which is important in the detection of delayed dehiscence. (C) 2009 The WJG Press and Baishideng. All rights reserved.

Determination and Molecular Analysis of the Complete Genome Sequence of Two Wild-Type Rabies Viruses Isolated from a Haematophagous Bat and a Frugivorous Bat in Brazil

The complete genome sequences of two Brazilian wild-type rabies viruses (RABV), a BR-DR1 isolate from a haematophagous bat (Desmodus rotundus) and a BR-AL1 isolate from a frugivorous bat (Artibeus lituratus), were determined. The genomes of the BR-DR1 and RR-AL1 had 11,923 and 11,922 nt, respectively, and both encoded the five standard genes of rhabdoviruses. The complete nucleotide sequence identity between the BR-DR1 and BR-AL1 isolates was 97%. The BR-DR1 and BR-AL1 isolates had some conserved functional sites revealed by the fixed isolates, whereas both isolates had unique amino acid substitutions in the antigenic region IV of the nucleocapsid gene. Therefore, it is speculated that both isolates were nearly identical in virologic character. According to our phylogenetic analysis based on the complete genomes, both isolates belonged to genotype 1, and to the previously defined ""vampire bat-related RABV lineage"" which consisted of mainly D. rotundus- and A. lituratus- isolates; however, a branch pattern with high bootstrap values suggested that BR-DR1 was more closely related to the 9001FRA isolate, which was collected from a dog bitten by a bat in French Guiana, than to BR-AL1. This result suggests that the vampire bat-related RABV lineage includes Brazilian vampire bat and Brazilian frugivorous bat RABV and is further divided into Brazilian vampire bat and Brazilian frugivorous bat RABV sub-lineages. The phylogenetic analysis based on the complete genomes was valuable in discriminating among very closely related isolates.

Stability of higher dimensional Reissner-Nordstrom-anti-de Sitter black holes

We investigate stability of the D-dimensional Reissner-Nordstrom-anti-de Sitter metrics as solutions of the Einstein-Maxwell equations. We have shown that asymptotically anti-de Sitter (AdS) black holes are dynamically stable for all values of charge and anti-de Sitter radius in D=5,6...11 dimensional space-times. This does not contradict dynamical instability of RNAdS black holes found by Gubser in N=8 gauged supergravity, because the latter instability comes from the tachyon mode of the scalar field, coupled to the system. Asymptotically AdS black holes are known to be thermodynamically unstable for some region of parameters, yet, as we have shown here, they are stable against gravitational perturbations.

Density functional theory investigation of 3d, 4d, and 5d 13-atom metal clusters

The knowledge of the atomic structure of clusters composed by few atoms is a basic prerequisite to obtain insights into the mechanisms that determine their chemical and physical properties as a function of diameter, shape, surface termination, as well as to understand the mechanism of bulk formation. Due to the wide use of metal systems in our modern life, the accurate determination of the properties of 3d, 4d, and 5d metal clusters poses a huge problem for nanoscience. In this work, we report a density functional theory study of the atomic structure, binding energies, effective coordination numbers, average bond lengths, and magnetic properties of the 3d, 4d, and 5d metal (30 elements) clusters containing 13 atoms, M(13). First, a set of lowest-energy local minimum structures (as supported by vibrational analysis) were obtained by combining high-temperature first- principles molecular-dynamics simulation, structure crossover, and the selection of five well-known M(13) structures. Several new lower energy configurations were identified, e. g., Pd(13), W(13), Pt(13), etc., and previous known structures were confirmed by our calculations. Furthermore, the following trends were identified: (i) compact icosahedral-like forms at the beginning of each metal series, more opened structures such as hexagonal bilayerlike and double simple-cubic layers at the middle of each metal series, and structures with an increasing effective coordination number occur for large d states occupation. (ii) For Au(13), we found that spin-orbit coupling favors the three-dimensional (3D) structures, i.e., a 3D structure is about 0.10 eV lower in energy than the lowest energy known two-dimensional configuration. (iii) The magnetic exchange interactions play an important role for particular systems such as Fe, Cr, and Mn. (iv) The analysis of the binding energy and average bond lengths show a paraboliclike shape as a function of the occupation of the d states and hence, most of the properties can be explained by the chemistry picture of occupation of the bonding and antibonding states.

Identification of Novel Immunoregulatory Molecules in Human Thymic Regulatory CD4(+)CD25(+) T Cells by Phage Display

Thymic CD4(+)CD25(+) cells play an important role in immune regulation and are continuously developed in the thymus as an independent lineage. How these cells are generated, what are their multiple pathways of suppressive activity and which are their specific markers are questions that remain unanswered. To identify molecules involved in the function and development of human CD4(+)CD25(+) T regulatory cells we targeted thymic CD4(+)CD25(+) cells by peptide phage display. A phage library containing random peptides was screened ex vivo for binding to human thymic CD4(+)CD25(+) T cells. After four rounds of selection on CD4(+)CD25(+) enriched populations of thymocytes, we sequenced several phage displayed peptides and selected one with identity to the Vitamin D Receptor (VDR). We confirmed the binding of the VDR phage to active Vitamin D in vitro, as well as the higher expression of VDR in CD4(+)CD25(+) cells. We suggest that differential expression of VDR on natural Tregs may be related to the relevance of Vitamin D in function and ontogeny of these cells.