Atrophy and Neuron Loss: Effects of a Protein-Deficient Diet on Sympathetic Neurons

Protein deficiency is one of the biggest public health problems in the world, accounting for about 30-40% of hospital admissions in developing countries. Nutritional deficiencies lead to alterations in the peripheral nervous system and in the digestive system. Most studies have focused on the effects of protein-deficient diets on the enteric neurons, but not on sympathetic ganglia, which supply extrinsic sympathetic input to the digestive system. Hence, in this study, we investigated whether a protein-restricted diet would affect the quantitative structure of rat coeliac ganglion neurons. Five male Wistar rats (undernourished group) were given a pre- and postnatal hypoproteinic diet receiving 5% casein, whereas the nourished group (n = 5) was fed with 20% casein (normoproteinic diet). Blood tests were carried out on the animals, e.g., glucose, leptin, and triglyceride plasma concentrations. The main structural findings in this study were that a protein-deficient diet (5% casein) caused coeliac ganglion (78%) and coeliac ganglion neurons (24%) to atrophy and led to neuron loss (63%). Therefore, the fall in the total number of coeliac ganglion neurons in protein-restricted rats contrasts strongly with no neuron losses previously described for the enteric neurons of animals subjected to similar protein-restriction diets. Discrepancies between our figures and the data for enteric neurons (using very similar protein-restriction protocols) may be attributable to the counting method used. In light of this, further systematic investigations comparing 2-D and 3-D quantitative methods are warranted to provide even more advanced data on the effects that a protein-deficient diet may exert on sympathetic neurons. (C) 2009 Wiley-Liss, Inc.

Tissue distribution of quiescin Q6/sulfhydryl oxidase (QSOX) in developing mouse

Quiescin Q6/sulfhydryl oxidases (QSOX) are revisited thiol oxidases considered to be involved in the oxidative protein folding, cell cycle control and extracellular matrix remodeling. They contain thioredoxin domains and introduce disulfide bonds into proteins and peptides, with the concomitant hydrogen peroxide formation, likely altering the redox environment. Since it is known that several developmental processes are regulated by the redox state, here we assessed if QSOX could have a role during mouse fetal development. For this purpose, an anti-recombinant mouse QSOX antibody was produced and characterized. In E-13.5, E-16.5 fetal tissues, QSOX immunostaining was confined to mesoderm- and ectoderm-derived tissues, while in P1 neonatal tissues it was slightly extended to some endoderm-derived tissues. QSOX expression, particularly by epithelial tissues, seemed to be developmentally-regulated, increasing with tissue maturation. QSOX was observed in loose connective tissues in all stages analyzed, intra and possibly extracellularly, in agreement with its putative role in oxidative folding and extracellular matrix remodeling. In conclusion, QSOX is expressed in several tissues during mouse development, but preferentially in those derived from mesoderm and ectoderm, suggesting it could be of relevance during developmental processes.

Effects of isoflavones on the coagulation and fibrinolytic system of postmenopausal women

Objective: We evaluated the effects of soy isoflavone supplementation on hemostasis in healthy postmenopausal women. Methods: In this double-blinded, placebo-controlled study, 47 postmenopausal women 47-66 y of age received 40 mg of soy isoflavone (n = 25) or 40 mg of casein placebo (n = 22) once a day for 6 mo. Levels of factors VII and X. fibrinogen, thrombin-antithrombin complex, prothrombin fragments I plus 2, antithrombin, protein C, total and free protein S, plasminogen, plasminogen activator inhibitor-1, and D-dimers were measured at baseline and 6 mo. Urinary isoflavone concentrations (genistein and daidzein) were measured as a marker of compliance and absorption using high-performance liquid chromatography. Baseline characteristics were compared by unpaired Student`s t test. Within-group changes and comparison between the isoflavone and casein placebo groups were determined by a mixed effects model. Results: The levels of hemostatic variables did not change significantly throughout the study in the isoflavone group; however, the isoflavone group showed a statistically significant reduction in plasma concentration of prothrombin fragments I plus 2; both groups showed a statistically significant reduction in antithrombin, protein C, and free protein S levels. A significant increase in D-dimers was observed only in the isoflavone group. Plasminogen activator inhibitor-l levels increased significantly in the placebo group. However, these changes were not statistically different between groups. Conclusion: The results of the present study do not support a biologically significant estrogenic effect of soy isoflavone on coagulation and fibrinolysis in postmenopausal women. However, further research will be necessary to definitively assess the safety and efficacy of isoflavone. (D 2008 Elsevier Inc. All rights reserved.

Functional Characterization of LcpA, a Surface-Exposed Protein of Leptospira spp. That Binds the Human Complement Regulator C4BP

We have previously shown that pathogenic leptospiral strains are able to bind C4b binding protein (C4BP). Surface-bound C4BP retains its cofactor activity, indicating that acquisition of this complement regulator may contribute to leptospiral serum resistance. In the present study, the abilities of seven recombinant putative leptospiral outer membrane proteins to interact with C4BP were evaluated. The protein encoded by LIC11947 interacted with this human complement regulator in a dose-dependent manner. The cofactor activity of C4BP bound to immobilized recombinant LIC11947 (rLIC11947) was confirmed by detecting factor I-mediated cleavage of C4b. rLIC11947 was therefore named LcpA (for leptospiral complement regulator-acquiring protein A). LcpA was shown to be an outer membrane protein by using immunoelectron microscopy, cell surface proteolysis, and Triton X-114 fractionation. The gene coding for LcpA is conserved among pathogenic leptospiral strains. This is the first characterization of a Leptospira surface protein that binds to the human complement regulator C4BP in a manner that allows this important regulator to control complement system activation mediated either by the classical pathway or by the lectin pathway. This newly identified protein may play a role in immune evasion by Leptospira spp. and may therefore represent a target for the development of a human vaccine against leptospirosis.

Immune Evasion of Leptospira Species by Acquisition of Human Complement Regulator C4BP

Leptospirosis is a spirochetal zoonotic disease of global distribution with a high incidence in tropical regions. In the last 15 years it has been recognized as an important emerging infectious disease due to the occurrence of large outbreaks in warm-climate countries and, occasionally, in temperate regions. Pathogenic leptospires efficiently colonize target organs after penetrating the host. Their invasiveness is attributed to the ability to multiply in blood, adhere to host cells, and penetrate into tissues. Therefore, they must be able to evade the innate host defense. The main purpose of the present study was to evaluate how several Leptospira strains evade the protective function of the complement system. The serum resistance of six Leptospira strains was analyzed. We demonstrate that the pathogenic strain isolated from infected hamsters avoids serum bactericidal activity more efficiently than the culture-attenuated or the nonpathogenic Leptospira strains. Moreover, both the alternative and the classical pathways of complement seem to be responsible for the killing of leptospires. Serum-resistant and serum-intermediate strains are able to bind C4BP, whereas the serum-sensitive strain Patoc I is not. Surface-bound C4BP promotes factor I-mediated cleavage of C4b. Accordingly, we found that pathogenic strains displayed reduced deposition of the late complement components C5 to C9 upon exposure to serum. We conclude that binding of C4BP contributes to leptospiral serum resistance against host complement.

Lack of effects of isoflavones on the lipid profile of Brazilian postmenopausal women

Objective: To evaluate the effects of soy isoflavone supplementation on profile lipid and endogenous hormone levels. Methods: In this double-blind, placebo-controlled Study, 47 post menopausal women 47-66 v of age received 40 mg of isoflavone (n = 25) or 40 mg of casein placebo (11 = 22). Cardiovascular risk factors were assessed by evaluating lipid profile at baseline and after 6 mo of treatment. To examine the effects of this regime on endogenous hormone levels, follicle-stimulating hormone and beta-estradiol were measured. Urinary isoflavone concentrations (genistein and daidzein) were measured as markers of both compliance and absorption using high performance liquid chromatography. Baseline characteristics were compared by the unpaired Student`s t-test. Within-group changes were determined by paired Student`s t-test and comparison between the isoflavone and casein placebo groups were determined by analysis of variance. Results: Lipid levels (low-density lipoprotein and total cholesterol) similarly decreased in both,groups. High-density lipoprotein increased significantly in both groups and cannot thus be attributable to treatment: the reason for Such variation is unknown and can be attributed to chance or to bias (even that of a real placebo effect in both groups or perhaps in spontaneous changes in exercise and dietary habits of patients after their inclusion). Furthermore, in both groups very low-density lipoprotein and triacylglycerol levels increased in a non-significant manner. Conclusion: The results of the present Study do not support any biologically significant estrogenic effects of isoflavone on the parameters assessed. Further research will he necessary to definitively assess the safety and efficacy of isoflavone. (C) 2008 Elsevier Inc. All rights reserved.

Putative outer membrane proteins of Leptospira interrogans stimulate human umbilical vein endothelial cells (HUVECS) and express during infection

Cell adhesion molecules (CAMs) are surface receptors present in eukaryotic cells that mediate cell-cell or cell-extracellular matrix interactions. Vascular endothelium stimulation in vitro that lead to the upregulation of CAMs was reported for the pathogenic spirochaetes, including rLIC10365 of Leptospira interrogans. In this study, we report the cloning of LIC10507, LIC10508, LIC10509 genes of L interrogans using Escherichia coli as a host system. The rational for selecting these sequences is due to their location in L. interrogans serovar Copenhageni genome that has a potential involvement in pathogenesis. The genes encode for predicted lipoproteins with no assigned functions. The purified recombinant proteins were capable to promote the upregulation of intercellular adhesion molecule 1 (ICAM-1) and E-selectin on monolayers of human umbilical vein endothelial cells (HUVECS). In addition, the coding sequences are expressed in the renal tubules of animal during bacterial experimental infection. The proteins are probably located at the outer membrane of the bacteria since they are detected in detergent-phase of L interrogans Triton X-114 extract. Altogether our data suggest a possible involvement of these proteins during bacterial infection and provide new insights into the role of this region in the pathogenesis of Leptospira. (C) 2008 Elsevier Ltd. All rights reserved.

Software reuse: The Brazilian industry scenario

This paper aims at identifying some of the key factors in adopting an organization-wide software reuse program. The factors are derived from practical experience reported by industry professionals, through a survey involving 57 Brazilian small, medium and large software organizations. Some of them produce software with commonality between applications, and have mature processes, while others successfully achieved reuse through isolated, ad hoe efforts. The paper compiles the answers from the survey participants, showing which factors were more associated with reuse success. Based on this relationship, a guide is presented, pointing out which factors should be more strongly considered by small, medium and large organizations attempting to establish a reuse program. (C) 2007 Elsevier Inc. All rights reserved.

Lot sizing and furnace scheduling in small foundries

A lot sizing and scheduling problem prevalent in small market-driven foundries is studied. There are two related decision levels: (I the furnace scheduling of metal alloy production, and (2) moulding machine planning which specifies the type and size of production lots. A mixed integer programming (MIP) formulation of the problem is proposed, but is impractical to solve in reasonable computing time for non-small instances. As a result, a faster relax-and-fix (RF) approach is developed that can also be used on a rolling horizon basis where only immediate-term schedules are implemented. As well as a MIP method to solve the basic RF approach, three variants of a local search method are also developed and tested using instances based on the literature. Finally, foundry-based tests with a real-order book resulted in a very substantial reduction of delivery delays and finished inventory, better use of capacity, and much faster schedule definition compared to the foundry`s own practice. (c) 2006 Elsevier Ltd. All rights reserved.

Periodic window arising in the parameter space of an impact oscillator

In the bi-dimensional parameter space of an impact-pair system, shrimp-shaped periodic windows are embedded in chaotic regions. We show that a weak periodic forcing generates new periodic windows near the unperturbed one with its shape and periodicity. Thus, the new periodic windows are parameter range extensions for which the controlled periodic oscillations substitute the chaotic oscillations. We identify periodic and chaotic attractors by their largest Lyapunov exponents. (C) 2010 Elsevier B.V. All rights reserved.

Suppressing grazing chaos in impacting system by structural nonlinearity

In this note we investigate the influence of structural nonlinearity of a simple cantilever beam impacting system on its dynamic responses close to grazing incidence by a means of numerical simulation. To obtain a clear picture of this effect we considered two systems exhibiting impacting motion, where the primary stiffness is either linear (piecewise linear system) or nonlinear (piecewise nonlinear system). Two systems were studied by constructing bifurcation diagrams, basins of attractions, Lyapunov exponents and parameter plots. In our analysis we focused on the grazing transitions from no impact to impact motion. We observed that the dynamic responses of these two similar systems are qualitatively different around the grazing transitions. For the piecewise linear system, we identified on the parameter space a considerable region with chaotic behaviour, while for the piecewise nonlinear system we found just periodic attractors. We postulate that the structural nonlinearity of the cantilever impacting beam suppresses chaos near grazing. (C) 2007 Elsevier Ltd. All rights reserved.

Control and chaos for vibro-impact and non-ideal oscillators

In the paper, we discuss dynamics of two kinds of mechanical systems. Initially, we consider vibro-impact systems which have many implementations in applied mechanics, ranging from drilling machinery and metal cutting processes to gear boxes. Moreover, from the point of view of dynamical systems, vibro-impact systems exhibit a rich variety of phenomena, particularly chaotic motion. In this paper, we review recent works on the dynamics of vibro-impact systems, focusing on chaotic motion and its control. The considered systems are a gear-rattling model and a smart damper to suppress chaotic motion. Furthermore, we investigate systems with non-ideal energy source, represented by a limited power supply. As an example of a non-ideal system, we analyse chaotic dynamics of the damped Duffing oscillator coupled to a rotor. Then, we show how to use a tuned liquid damper to control the attractors of this non-ideal oscillator.

A portable Compton spectrometer for clinical X-ray beams in the energy range 20-150 keV

Primary beam spectra were obtained for an X-ray industrial equipment (40-150 kV), and for a clinical mammography apparatus (25-35 kV) from beams scattered at angles close to 90 degrees, measured with a CdTe Compton spectrometer. Actual scattering angles were determined from the Compton energy shift of characteristic X-rays or spectra end-point energy. Evaluated contribution of coherent scattering amounts to more than 15% of fluence in mammographic beams. This technique can be used in clinical environments. (C) 2010 Elsevier Ltd. All rights reserved.

Conversion coefficients from air kerma to personal dose equivalent in mammography

In this work, the scattered X-ray beams produced by a mammography unit with a Mo/Mo, Mo/Rh and W/Rh anode/filter combinations were applied in the evaluation of the Hp(10, 0) and mean conversion coefficients from air kerma to the personal dose equivalent ((C) over barH(p(10,0 degrees))). The higher values of H(p)(10,0 degrees) are related to the Mo/Rh combination whereas the lower ones are for the W/Rh target/filter. (C) over barH(p(10,0 degrees)) values are in the range 0.19-0.54 Sv/Gy, where the higher values comprise the W/Rh combination. (C) 2009 Elsevier Ltd. All rights reserved.

Compressible Sherrington-Kirkpatrick spin-glass model

We introduce a Sherrington-Kirkpatrick spin-glass model with the addition of elastic degrees of freedom. The problem is formulated in terms of an effective four-spin Hamiltonian in the pressure ensemble, which can be treated by the replica method. In the replica-symmetric approximation, we analyze the pressure-temperature phase diagram, and obtain expressions for the critical boundaries between the disordered and the ordered (spin-glass and ferromagnetic) phases. The second-order para-ferromagnetic border ends at a tricritical point, beyond which the transition becomes discontinuous. We use these results to make contact with the temperature-concentration phase diagrams of mixtures of hydrogen-bonded crystals.