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Showing papers by "University of São Paulo published in 2007"


Journal ArticleDOI
TL;DR: In this paper, the authors present a survey of topological features of complex networks, including trajectories in several measurement spaces, correlations between some of the most traditional measurements, perturbation analysis, as well as the use of multivariate statistics for feature selection and network classification.
Abstract: Each complex network (or class of networks) presents specific topological features which characterize its connectivity and highly influence the dynamics of processes executed on the network. The analysis, discrimination, and synthesis of complex networks therefore rely on the use of measurements capable of expressing the most relevant topological features. This article presents a survey of such measurements. It includes general considerations about complex network characterization, a brief review of the principal models, and the presentation of the main existing measurements. Important related issues covered in this work comprise the representation of the evolution of complex networks in terms of trajectories in several measurement spaces, the analysis of the correlations between some of the most traditional measurements, perturbation analysis, as well as the use of multivariate statistics for feature selection and network classification. Depending on the network and the analysis task one has in mind, a s...

2,140 citations


Journal ArticleDOI
09 Feb 2007-Science
TL;DR: Most of the “new renewable energy sources” are still undergoing large-scale commercial development, but some technologies are already well established and fully competitive with motor gasoline and appropriate for replication in many countries.
Abstract: Renewable energy is one of the most efficient ways to achieve sustainable development. Increasing its share in the world matrix will help prolong the existence of fossil fuel reserves, address the threats posed by climate change, and enable better security of the energy supply on a global scale. Most of the "new renewable energy sources" are still undergoing large-scale commercial development, but some technologies are already well established. These include Brazilian sugarcane ethanol, which, after 30 years of production, is a global energy commodity that is fully competitive with motor gasoline and appropriate for replication in many countries.

1,234 citations


Journal ArticleDOI
Vishvanath Nene1, Jennifer R. Wortman1, Daniel Lawson, Brian J. Haas1, Chinnappa D. Kodira2, Zhijian Jake Tu3, Brendan J. Loftus, Zhiyong Xi4, Karyn Megy, Manfred Grabherr2, Quinghu Ren1, Evgeny M. Zdobnov, Neil F. Lobo5, Kathryn S. Campbell6, Susan E. Brown7, Maria de Fatima Bonaldo8, Jingsong Zhu9, Steven P. Sinkins10, David G. Hogenkamp11, Paolo Amedeo1, Peter Arensburger9, Peter W. Atkinson9, Shelby L. Bidwell1, Jim Biedler3, Ewan Birney, Robert V. Bruggner5, Javier Costas, Monique R. Coy3, Jonathan Crabtree1, Matt Crawford2, Becky deBruyn5, David DeCaprio2, Karin Eiglmeier12, Eric Eisenstadt1, Hamza El-Dorry13, William M. Gelbart6, Suely Lopes Gomes13, Martin Hammond, Linda Hannick1, James R. Hogan5, Michael H. Holmes1, David M. Jaffe2, J. Spencer Johnston, Ryan C. Kennedy5, Hean Koo1, Saul A. Kravitz, Evgenia V. Kriventseva14, David Kulp15, Kurt LaButti2, Eduardo Lee1, Song Li3, Diane D. Lovin5, Chunhong Mao3, Evan Mauceli2, Carlos Frederico Martins Menck13, Jason R. Miller1, Philip Montgomery2, Akio Mori5, Ana L. T. O. Nascimento16, Horacio Naveira17, Chad Nusbaum2, Sinéad B. O'Leary2, Joshua Orvis1, Mihaela Pertea, Hadi Quesneville, Kyanne R. Reidenbach11, Yu-Hui Rogers, Charles Roth12, Jennifer R. Schneider5, Michael C. Schatz, Martin Shumway1, Mario Stanke, Eric O. Stinson5, Jose M. C. Tubio, Janice P. Vanzee11, Sergio Verjovski-Almeida13, Doreen Werner18, Owen White1, Stefan Wyder14, Qiandong Zeng2, Qi Zhao1, Yongmei Zhao1, Catherine A. Hill11, Alexander S. Raikhel9, Marcelo B. Soares8, Dennis L. Knudson7, Norman H. Lee, James E. Galagan2, Steven L. Salzberg, Ian T. Paulsen1, George Dimopoulos4, Frank H. Collins5, Bruce W. Birren2, Claire M. Fraser-Liggett, David W. Severson5 
22 Jun 2007-Science
TL;DR: A draft sequence of the genome of Aedes aegypti, the primary vector for yellow fever and dengue fever, which at approximately 1376 million base pairs is about 5 times the size of the genomes of the malaria vector Anopheles gambiae was presented in this paper.
Abstract: We present a draft sequence of the genome of Aedes aegypti, the primary vector for yellow fever and dengue fever, which at approximately 1376 million base pairs is about 5 times the size of the genome of the malaria vector Anopheles gambiae. Nearly 50% of the Ae. aegypti genome consists of transposable elements. These contribute to a factor of approximately 4 to 6 increase in average gene length and in sizes of intergenic regions relative to An. gambiae and Drosophila melanogaster. Nonetheless, chromosomal synteny is generally maintained among all three insects, although conservation of orthologous gene order is higher (by a factor of approximately 2) between the mosquito species than between either of them and the fruit fly. An increase in genes encoding odorant binding, cytochrome P450, and cuticle domains relative to An. gambiae suggests that members of these protein families underpin some of the biological differences between the two mosquito species.

1,107 citations


Journal ArticleDOI
TL;DR: The aim of this study was to improve the neuropathologic recognition and provide criteria for the pathological diagnosis in the neurodegenerative diseases grouped as frontotemporal lobar degeneration (FTLD) and incorporate up-to-date neuropathology in the light of recent immunohistochemical, biochemical, and genetic advances.
Abstract: The aim of this study was to improve the neuropathologic recognition and provide criteria for the pathological diagnosis in the neurodegenerative diseases grouped as frontotemporal lobar degeneration (FTLD); revised criteria are proposed. Recent advances in molecular genetics, biochemistry, and neuropathology of FTLD prompted the Midwest Consortium for Frontotemporal Lobar Degeneration and experts at other centers to review and revise the existing neuropathologic diagnostic criteria for FTLD. The proposed criteria for FTLD are based on existing criteria, which include the tauopathies [FTLD with Pick bodies, corticobasal degeneration, progressive supranuclear palsy, sporadic multiple system tauopathy with dementia, argyrophilic grain disease, neurofibrillary tangle dementia, and FTD with microtubule-associated tau (MAPT) gene mutation, also called FTD with parkinsonism linked to chromosome 17 (FTDP-17)]. The proposed criteria take into account new disease entities and include the novel molecular pathology, TDP-43 proteinopathy, now recognized to be the most frequent histological finding in FTLD. TDP-43 is a major component of the pathologic inclusions of most sporadic and familial cases of FTLD with ubiquitin-positive, tau-negative inclusions (FTLD-U) with or without motor neuron disease (MND). Molecular genetic studies of familial cases of FTLD-U have shown that mutations in the progranulin (PGRN) gene are a major genetic cause of FTLD-U. Mutations in valosin-containing protein (VCP) gene are present in rare familial forms of FTD, and some families with FTD and/or MND have been linked to chromosome 9p, and both are types of FTLD-U. Thus, familial TDP-43 proteinopathy is associated with defects in multiple genes, and molecular genetics is required in these cases to correctly identify the causative gene defect. In addition to genetic heterogeneity amongst the TDP-43 proteinopathies, there is also neuropathologic heterogeneity and there is a close relationship between genotype and FTLD-U subtype. In addition to these recent significant advances in the neuropathology of FTLD-U, novel FTLD entities have been further characterized, including neuronal intermediate filament inclusion disease. The proposed criteria incorporate up-to-date neuropathology of FTLD in the light of recent immunohistochemical, biochemical, and genetic advances. These criteria will be of value to the practicing neuropathologist and provide a foundation for clinical, clinico-pathologic, mechanistic studies and in vivo models of pathogenesis of FTLD.

1,000 citations


Journal ArticleDOI
TL;DR: The ICTP Regional Climate Model version 3 (RegCM3) as mentioned in this paper is a state-of-the-art regional climate model, which is used by a large research community for a diverse range of climate-related studies.
Abstract: Regional climate models are important research tools available to scientists around the world, including in economically developing nations (EDNs). The Earth Systems Physics (ESP) group of the Abdus Salam International Centre for Theoretical Physics (ICTP) maintains and distributes a state-of-the-science regional climate model called the ICTP Regional Climate Model version 3 (RegCM3), which is currently being used by a large research community for a diverse range of climate-related studies. The RegCM3 is the central, but not only, tool of the ICTP-maintained Regional Climate Research Network (RegCNET) aimed at creating south–south and north–south scientific interactions on the topic of climate and associated impacts research and modeling. In this paper, RegCNET, RegCM3, and illustrative results from RegCM3 benchmark simulations applied over south Asia, Africa, and South America are presented. It is shown that RegCM3 performs reasonably well over these regions and is therefore useful for climate studies in...

939 citations


Journal ArticleDOI
TL;DR: The current review describes the main substances biosynthesized by algae with potential economic impact in food science, pharmaceutical industry and public health.
Abstract: In order to survive in a highly competitive environment, freshwater or marine algae have to develop defense strategies that result in a tremendous diversity of compounds from different metabolic pathways. Recent trends in drug research from natural sources have shown that algae are promising organisms to furnish novel biochemically active compounds. The current review describes the main substances biosynthesized by algae with potential economic impact in food science, pharmaceutical industry and public health. Emphasis is given to fatty acids, steroids, carotenoids, polysaccharides, lectins, mycosporine-like amino acids, halogenated compounds, polyketides and toxins.

849 citations


Journal ArticleDOI
TL;DR: The results represent the most precise estimates available of the independent association of each of the two main risk factors of head and neck cancer, and they exemplify the strengths of large-scale consortia in cancer epidemiology.
Abstract: Background At least 75% of head and neck cancers are attributable to a combination of cigarette smoking and alcohol drinking. A precise understanding of the independent association of each of these factors in the absence of the other with the risk of head and neck cancer is needed to elucidate mechanisms of head and neck carcinogenesis and to assess the efficacy of interventions aimed at controlling either risk factor. Methods We examined the extent to which head and neck cancer is associated with cigarette smoking among never drinkers and with alcohol drinking among never users of tobacco. We pooled individual-level data from 15 case – control studies that included 10 244 head and neck cancer case subjects and 15 227 control subjects, of whom 1072 case subjects and 5775 control subjects were never users of tobacco and 1598 case subjects and 4051 control subjects were never drinkers of alcohol. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using unconditional logistic regression models. All statistical tests were two-sided. Results Among never drinkers, cigarette smoking was associated with an increased risk of head and neck cancer (OR for ever versus never smoking = 2.13, 95% CI = 1.52 to 2.98), and there were clear dose – response relationships for the frequency, duration, and number of pack-years of cigarette smoking. Approximately 24% (95% CI = 16% to 31%) of head and neck cancer cases among nondrinkers in this study would have been prevented if these individuals had not smoked cigarettes. Among never users of tobacco, alcohol consumption was associated with an increased risk of head and neck cancer only when alcohol was consumed at high frequency (OR for three or more drinks per day versus never drinking = 2.04, 95% CI = 1.29 to 3.21). The association with high-frequency alcohol intake was limited to cancers of the oropharynx/hypopharynx and larynx. Conclusions Our results represent the most precise estimates available of the independent association of each of the two main risk factors of head and neck cancer, and they exemplify the strengths of large-scale consortia in cancer epidemiology. J Natl Cancer Inst 2007;99: 777 – 89

849 citations


Journal ArticleDOI
TL;DR: The use of the PICO strategy for the construction of the research question and bibliographical search is described.
Abstract: Evidence based practice is the use of the best scientific evidence to support the clinical decision making. The identification of the best evidence requires the construction of an appropriate research question and review of the literature. This article describes the use of the PICO strategy for the construction of the research question and bibliographical search.

833 citations


Journal ArticleDOI
01 Aug 2007
TL;DR: It is shown that C3H/HeJ mice, which have a loss-of-function mutation in TLR4, are protected against the development of diet-induced obesity and a potential target for the therapy of these highly prevalent medical conditions.
Abstract: Obesity is associated with insulin resistance and a state of abnormal inflammatory response. The Toll-like receptor (TLR)4 has an important role in inflammation and immunity, and its expression has been reported in most tissues of the body, including the insulin-sensitive ones. Because it is activated by lipopolysaccharide and saturated fatty acids, which are inducers of insulin resistance, TLR4 may be a candidate for participation in the cross-talk between inflammatory and metabolic signals. Here, we show that C3H/HeJ mice, which have a loss-of-function mutation in TLR4, are protected against the development of diet-induced obesity. In addition, these mice demonstrate decreased adiposity, increased oxygen consumption, a decreased respiratory exchange ratio, improved insulin sensitivity, and enhanced insulin-signaling capacity in adipose tissue, muscle, and liver compared with control mice during high-fat feeding. Moreover, in these tissues, control mice fed a high-fat diet show an increase in IkappaB kinase complex and c-Jun NH(2)-terminal kinase activity, which is prevented in C3H/HeJ mice. In isolated muscles from C3H/HeJ mice, protection from saturated fatty acid-induced insulin resistance is observed. Thus, TLR4 appears to be an important mediator of obesity and insulin resistance and a potential target for the therapy of these highly prevalent medical conditions.

809 citations


Journal ArticleDOI
J. Abraham1, P. Abreu2, Marco Aglietta3, C. Aguirre  +449 moreInstitutions (69)
09 Nov 2007-Science
TL;DR: In this article, the authors demonstrate that there is a correlation between the arrival directions of cosmic rays with energy above 6 x 10{sup 19} eV and the positions of active galactic nuclei lying within 75 Mpc.
Abstract: Using data collected at the Pierre Auger Observatory during the past 3.7 years, we demonstrate that there is a correlation between the arrival directions of cosmic rays with energy above {approx} 6 x 10{sup 19} eV and the positions of active galactic nuclei (AGN) lying within {approx} 75 Mpc. We reject the hypothesis of an isotropic distribution of these cosmic rays at over 99% confidence level from a prescribed a priori test. The correlation we observe is compatible with the hypothesis that the highest energy particles originate from nearby extragalactic sources whose flux has not been significantly reduced by interaction with the cosmic background radiation. AGN or objects having a similar spatial distribution are possible sources.

798 citations


Journal ArticleDOI
TL;DR: It is demonstrated that dendritic cells modified by Treg cells induced the generation of IL-10-producing Tr1 cells, and IL-27 and transforming growth factor-β promote the generation.
Abstract: Regulatory T cells (Treg cells) expressing the transcription factor Foxp3 are key in maintaining the balance of immune homeostasis. However, distinct induced T regulatory type 1 (Tr1) cells that lack Foxp3 expression also regulate T cell function, mainly by producing the immunosuppressive cytokine interleukin 10 (IL-10). However, the factors required for the induction of IL-10-producing suppressive T cells are not fully understood. Here we demonstrate that dendritic cells modified by Treg cells induced the generation of IL-10-producing Tr1 cells. The differentiation of naive CD4+ T cells into IL-10-producing cells was mediated by IL-27 produced by the Treg cell–modified dendritic cells, and transforming growth factor-β amplified the generation of induced IL-10+ Tr1 cells by IL-27. Thus, IL-27 and transforming growth factor-β promote the generation of IL-10-producing Tr1 cells.

Journal ArticleDOI
TL;DR: The main environmental factors that can streamline or alter the production or concentration of secondary metabolites in plants are reviewed.
Abstract: Since secondary metabolites represent a chemical interface between plants and surrounding environment, their syntheses are frequently affected by environmental conditions. Thus, variations in the total content and/or of the relative proportions of secondary metabolites in plants can take place. We review the main environmental factors that can streamline or alter the production or concentration of secondary metabolites in plants. How seasonality, circadian rhythm, developmental stage and age, temperature, water availability, UV radiation, soil nutrients, altitude, atmospheric composition and tissue damage influence secondary metabolism are discussed.

Journal ArticleDOI
TL;DR: It is shown that pseudogene formation and gene loss are the principal forces shaping the different genomes of Leishmania, and genes that are differentially distributed between the species encode proteins implicated in host-pathogen interactions and parasite survival in the macrophage.
Abstract: Leishmania parasites cause a broad spectrum of clinical disease. Here we report the sequencing of the genomes of two species of Leishmania: Leishmania infantum and Leishmania braziliensis. The comparison of these sequences with the published genome of Leishmania major reveals marked conservation of synteny and identifies only 200 genes with a differential distribution between the three species. L. braziliensis, contrary to Leishmania species examined so far, possesses components of a putative RNA-mediated interference pathway, telomere-associated transposable elements and spliced leader–associated SLACS retrotransposons. We show that pseudogene formation and gene loss are the principal forces shaping the different genomes. Genes that are differentially distributed between the species encode proteins implicated in host-pathogen interactions and parasite survival in the macrophage.

Journal ArticleDOI
14 Nov 2007-JAMA
TL;DR: Despite gaps in the evidence base, current knowledge is sufficient to make practical recommendations to guide appropriate evaluation, management, and etiologic treatment of Chagas disease.
Abstract: ContextBecause of population migration from endemic areas and newly instituted blood bank screening, US clinicians are likely to see an increasing number of patients with suspected or confirmed chronic Trypanosoma cruzi infection (Chagas disease).ObjectiveTo examine the evidence base and provide practical recommendations for evaluation, counseling, and etiologic treatment of patients with chronic T cruzi infection.Evidence AcquisitionLiterature review conducted based on a systematic MEDLINE search for all available years through 2007; review of additional articles, reports, and book chapters; and input from experts in the field.Evidence SynthesisThe patient newly diagnosed with Chagas disease should undergo a medical history, physical examination, and resting 12-lead electrocardiogram (ECG) with a 30-second lead II rhythm strip. If this evaluation is normal, no further testing is indicated; history, physical examination, and ECG should be repeated annually. If findings suggest Chagas heart disease, a comprehensive cardiac evaluation, including 24-hour ambulatory ECG monitoring, echocardiography, and exercise testing, is recommended. If gastrointestinal tract symptoms are present, barium contrast studies should be performed. Antitrypanosomal treatment is recommended for all cases of acute and congenital Chagas disease, reactivated infection, and chronic T cruzi infection in individuals 18 years or younger. In adults aged 19 to 50 years without advanced heart disease, etiologic treatment may slow development and progression of cardiomyopathy and should generally be offered; treatment is considered optional for those older than 50 years. Individualized treatment decisions for adults should balance the potential benefit, prolonged course, and frequent adverse effects of the drugs. Strong consideration should be given to treatment of previously untreated patients with human immunodeficiency virus infection or those expecting to undergo organ transplantation.ConclusionsChagas disease presents an increasing challenge for clinicians in the United States. Despite gaps in the evidence base, current knowledge is sufficient to make practical recommendations to guide appropriate evaluation, management, and etiologic treatment of Chagas disease.

Journal ArticleDOI
TL;DR: Among the interventions to preserve or "rejuvenate" beta-cells, short-term intensive insulin therapy of newly diagnosed type 2 diabetes will improve beta-cell function, usually leading to a temporary remission time and the use of antiapoptotic drugs, such as the thiazolidinediones (TZDs), and incretin mimetics and enhancers, which have demonstrated significant clinical evidence of effects on human beta- cell function.
Abstract: There is a progressive deterioration in beta-cell function and mass in type 2 diabetics. It was found that islet function was about 50% of normal at the time of diagnosis, and a reduction in beta-cell mass of about 60% was shown at necropsy. The reduction of beta-cell mass is attributable to accelerated apoptosis. The major factors for progressive loss of beta-cell function and mass are glucotoxicity, lipotoxicity, proinflammatory cytokines, leptin, and islet cell amyloid. Impaired beta-cell function and possibly beta-cell mass appear to be reversible, particularly at early stages of the disease where the limiting threshold for reversibility of decreased beta-cell mass has probably not been passed. Among the interventions to preserve or "rejuvenate" beta-cells, short-term intensive insulin therapy of newly diagnosed type 2 diabetes will improve beta-cell function, usually leading to a temporary remission time. Another intervention is the induction of beta-cell "rest" by selective activation of ATP-sensitive K+ (K(ATP)) channels, using drugs such as diazoxide. A third type of intervention is the use of antiapoptotic drugs, such as the thiazolidinediones (TZDs), and incretin mimetics and enhancers, which have demonstrated significant clinical evidence of effects on human beta-cell function. The TZDs improve insulin secretory capacity, decrease beta-cell apoptosis, and reduce islet cell amyloid with maintenance of neogenesis. The TZDs have indirect effects on beta-cells by being insulin sensitizers. The direct effects are via peroxisome proliferator-activated receptor gamma activation in pancreatic islets, with TZDs consistently improving basal beta-cell function. These beneficial effects are sustained in some individuals with time. There are several trials on prevention of diabetes with TZDs. Incretin hormones, which are released from the gastrointestinal tract in response to nutrient ingestion to enhance glucose-dependent insulin secretion from the pancreas, aid the overall maintenance of glucose homeostasis through slowing of gastric emptying, inhibition of glucagon secretion, and control of body weight. From the two major incretins, glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP), only the first one or its mimetics or enhancers can be used for treatment because the diabetic beta-cell is resistant to GIP action. Because of the rapid inactivation of GLP-1 by dipeptidyl peptidase (DPP)-IV, several incretin analogs were developed: GLP-1 receptor agonists (incretin mimetics) exenatide (synthetic exendin-4) and liraglutide, by conjugation of GLP-1 to circulating albumin. The acute effect of GLP-1 and GLP-1 receptor agonists on beta-cells is stimulation of glucose-dependent insulin release, followed by enhancement of insulin biosynthesis and stimulation of insulin gene transcription. The chronic action is stimulating beta-cell proliferation, induction of islet neogenesis, and inhibition of beta-cell apoptosis, thus promoting expansion of beta-cell mass, as observed in rodent diabetes and in cultured beta-cells. Exenatide and liraglutide enhanced postprandial beta-cell function. The inhibition of the activity of the DPP-IV enzyme enhances endogenous GLP-1 action in vivo, mediated not only by GLP-1 but also by other mediators. In preclinical studies, oral active DPP-IV inhibitors (sitagliptin and vildagliptin) also promoted beta-cell proliferation, neogenesis, and inhibition of apoptosis in rodents. Meal tolerance tests showed improvement in postprandial beta-cell function. Obviously, it is difficult to estimate the protective effects of incretin mimetics and enhancers on beta-cells in humans, and there is no clinical evidence that these drugs really have protective effects on beta-cells.

Journal ArticleDOI
TL;DR: Patients with septic AKI had an increased risk for death and longer duration of hospitalization yet showed trends toward greater renal recovery and independence from RRT.
Abstract: Sepsis is the most common cause of acute kidney injury (AKI) in critical illness, but there is limited information on septic AKI. A prospective, observational study of critically ill patients with septic and nonseptic AKI was performed from September 2000 to December 2001 at 54 hospitals in 23 countries. A total of 1753 patients were enrolled. Sepsis was considered the cause in 833 (47.5%); the predominant sources of sepsis were chest and abdominal (54.3%). Septic AKI was associated with greater aberrations in hemodynamics and laboratory parameters, greater severity of illness, and higher need for mechanical ventilation and vasoactive therapy. There was no difference in enrollment kidney function or in the proportion who received renal replacement therapy (RRT; 72 versus 71%; P = 0.83). Oliguria was more common in septic AKI (67 versus 57%; P < 0.001). Septic AKI had a higher in-hospital case-fatality rate compared with nonseptic AKI (70.2 versus 51.8%; P < 0.001). After adjustment for covariates, septic AKI remained associated with higher odds for death (1.48; 95% confidence interval 1.17 to 1.89; P = 0.001). Median (IQR) duration of hospital stay for survivors (37 [19 to 59] versus 21 [12 to 42] d; P < 0.0001) was longer for septic AKI. There was a trend to lower serum creatinine (106 [73 to 158] versus 121 [88 to 184] mumol/L; P = 0.01) and RRT dependence (9 versus 14%; P = 0.052) at hospital discharge for septic AKI. Patients with septic AKI were sicker and had a higher burden of illness and greater abnormalities in acute physiology. Patients with septic AKI had an increased risk for death and longer duration of hospitalization yet showed trends toward greater renal recovery and independence from RRT.

Journal ArticleDOI
TL;DR: Non-digestible oligosaccharides possess important physicochemical and physiological properties, and are claimed to behave as dietary fibers and prebiotics, which gives opportunity for improving of gut microecology including bacterial populations, biochemical profiles and physiological effects.

Journal ArticleDOI
TL;DR: Evidence from studies in animal models and in anima nobile points to 4 main pathogenetic mechanisms to explain the development of chronic Chagas heart disease: autonomic nervous system derangements, microvascular disturbances, parasite-dependent myocardial aggression, and immune-mediatedMyocardial injury.
Abstract: Background— Chagas disease remains a significant public health issue and a major cause of morbidity and mortality in Latin America. Despite nearly 1 century of research, the pathogenesis of chronic Chagas cardiomyopathy is incompletely understood, the most intriguing challenge of which is the complex host-parasite interaction. Methods and Results— A systematic review of the literature found in MEDLINE, EMBASE, BIREME, LILACS, and SCIELO was performed to search for relevant references on pathogenesis and pathophysiology of Chagas disease. Evidence from studies in animal models and in anima nobile points to 4 main pathogenetic mechanisms to explain the development of chronic Chagas heart disease: autonomic nervous system derangements, microvascular disturbances, parasite-dependent myocardial aggression, and immune-mediated myocardial injury. Despite its prominent peculiarities, the role of autonomic derangements and microcirculatory disturbances is probably ancillary among causes of chronic myocardial damag...

Journal ArticleDOI
TL;DR: The objective of the present review is to discuss different aspects of the use of ILs in carbohydrate chemistry, in particular, dissolution and functionalization of simple sugars, cyclodextrins, cellulose, starch, and chitin/chitosan.

Journal ArticleDOI
TL;DR: Alterations in BMI were associated with dyslipidemic profile and oxidative stress in serum of rats and BMI may predict these adverse consequences of the obesity in rats.
Abstract: The present study was undertaken to determine anthropometrical parameters in male adult Wistar rats. We tested the hypothesis that the anthropometrical index may identify obesity and may predict its adverse effects on lipid profile and oxidative stress in rats. Two experimental protocols were performed. In the first experiment, 50 male Wistar rats, 21 days old and fed a control chow were studied up to 150 days of age. In the second experiment, male Wistar rats, 60 days old, were divided into three groups (n = 8): control (C) given free access to a control chow; (S) receiving the control chow and drinking 30% sucrose ad libitum and (HC) fed a high-carbohydrate diet ad libitum. The first experiment showed that food consumption, energy intake and body weight increased with increasing age, while specific rate of body mass gain was significantly decreased. There were no significant differences in body length and thoracic circumference of rats from 60 days of age. The abdominal circumference (AC) and body mass index (BMI) significantly increased with enhancing age in rats up to 90 days of age and remained constant thereafter. In the second experiment, after 30 days of dietary treatment, the final body weight, body mass gain, carcass fat and BMI were higher in S and HC rats than in C. There were no significant alterations in body length and carcass protein among the groups. Triacylglycerol (TG), total cholesterol (CT), low-density lipoprotein cholesterol (LDL-C) and lipid hydroperoxide (LH) were higher in S and HC rats than in C. High-density lipoprotein cholesterol (HDL-C) decreased in HC rats and total antioxidant substances (TAS) decreased in S and HC rats. There were positive correlations between BMI with carcass fat, BMI with LH and BMI and serum TG concentration. In conclusion, the BMI for male adult Wistar rats ranged between 0.45 and 0.68 g/cm(2). Obesity may be easily estimated from the BMI in rats. Alterations in BMI were associated with dyslipidemic profile and oxidative stress in serum of rats and BMI may predict these adverse consequences of the obesity in rats.

Journal ArticleDOI
TL;DR: In this article, a class of composite Higgs models arising from a warped extra dimension that can satisfy all the electroweak precision tests in a significant portion of their parameter space is presented. But their mass is not known.
Abstract: We present a class of composite Higgs models arising from a warped extra dimension that can satisfy all the electroweak precision tests in a significant portion of their parameter space. A custodial symmetry plays a crucial role in keeping the largest corrections to the electroweak observables below their experimental limits. In these models the heaviness of the top quark is not only essential to trigger the electroweak symmetry breaking, but it also implies that the lowest top resonance and its custodial partners, the custodians, are significantly lighter than the other resonances. These custodians are the trademark of these scenarios. They are exotic colored fermions of electromagnetic charges $5/3$, $2/3$, and $\ensuremath{-}1/3$, with masses predicted roughly in the range 500--1500 GeV. We discuss their production and detection at the CERN LHC.

Journal ArticleDOI
TL;DR: A diversity of phenomena are surveyed, which may be classified into no less than 11 areas, providing a clear indication of the impact of the field of complex networks.
Abstract: The success of new scientific areas can be assessed by their potential for contributing to new theoretical approaches and in applications to real-world problems. Complex networks have fared extremely well in both of these aspects, with their sound theoretical basis developed over the years and with a variety of applications. In this survey, we analyze the applications of complex networks to real-world problems and data, with emphasis in representation, analysis and modeling, after an introduction to the main concepts and models. A diversity of phenomena are surveyed, which may be classified into no less than 22 areas, providing a clear indication of the impact of the field of complex networks.

Journal ArticleDOI
TL;DR: NADPH oxidase associated ROS may be a useful target for intervention strategies based on reversing the negative impact of glucolipotoxicity in diabetes and may alter parameters of signal transduction, insulin secretion, insulin action and cell proliferation or cell death.
Abstract: It is now widely accepted, given the current weight of experimental evidence, that reactive oxygen species (ROS) contribute to cell and tissue dysfunction and damage caused by glucolipotoxicity in diabetes. The source of ROS in the insulin secreting pancreatic β-cells and in the cells which are targets for insulin action has been considered to be the mitochondrial electron transport chain. While this source is undoubtably important, we provide additional information and evidence for NADPH oxidase-dependent generation of ROS both in pancreatic β-cells and in insulin sensitive cells. While mitochondrial ROS generation may be important for regulation of mitochondrial uncoupling protein (UCP) activity and thus disruption of cellular energy metabolism, the NADPH oxidase associated ROS may alter parameters of signal transduction, insulin secretion, insulin action and cell proliferation or cell death. Thus NADPH oxidase may be a useful target for intervention strategies based on reversing the negative impact of glucolipotoxicity in diabetes.

Journal ArticleDOI
TL;DR: CABG was superior to MT in terms of the primary end points, reaching a significant 44% reduction at the 5-year follow-up of patients with stable multivessel coronary artery disease, and was associated with an incidence of long-term events and rate of additional revascularization similar to those for PCI.
Abstract: Background— Despite routine use of coronary artery bypass graft (CABG) and percutaneous coronary intervention (PCI), no conclusive evidence exists that either modality is superior to medical therapy (MT) alone for treating multivessel coronary artery disease with stable angina and preserved ventricular function. Methods and Results— The primary end points were total mortality, Q-wave myocardial infarction, or refractory angina requiring revascularization. The study comprised 611 patients randomly assigned to undergo CABG (n=203), PCI (n=205), or MT (n=203). At the 5-year follow-up, the primary end points occurred in 21.2% of patients who underwent CABG compared with 32.7% treated with PCI and 36% receiving MT alone (P=0.0026). No statistical differences were observed in overall mortality among the 3 groups. In addition, 9.4% of MT and 11.2% of PCI patients underwent repeat revascularization procedures compared with 3.9% of CABG patients (P=0.021). Moreover, 15.3%, 11.2%, and 8.3% of patients experienced n...

Journal ArticleDOI
TL;DR: This study tested the hypothesis that interfacial degradation of resin-dentin bonds may be prevented or delayed by the application of chlorhexidine (CHX), a matrix metalloproteinase inhibitor, to dentin after phosphoric acid-etching.
Abstract: Host-derived proteases have been reported to degrade the collagen matrix of incompletely-resin-infiltrated dentin. This study tested the hypothesis that interfacial degradation of resin-dentin bonds may be prevented or delayed by the application of chlorhexidine (CHX), a matrix metalloproteinase inhibitor, to dentin after phosphoric acid-etching. Contralateral pairs of resin-bonded Class I restorations in non-carious third molars were kept under intra-oral function for 14 months. Preservation of resin-dentin bonds was assessed by microtensile bond strength tests and TEM examination. In vivo bond strength remained stable in the CHX-treated specimens, while bond strength decreased significantly in control teeth. Resin-infiltrated dentin in CHX-treated specimens exhibited normal structural integrity of the collagen network. Conversely, progressive disintegration of the fibrillar network was identified in control specimens. Auto-degradation of collagen matrices can occur in resin-infiltrated dentin, but may be prevented by the application of a synthetic protease inhibitor, such as chlorhexidine.

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TL;DR: In this paper, the authors determined the kinetics of the ORR on the surfaces of single crystals of Au(111), Ag(111, Pd, Rh, Ir, and R...
Abstract: We determined, by the rotating disk electrode technique, the kinetics of the oxygen-reduction reaction (ORR) on the surfaces of single crystals of Au(111), Ag(111), Pd(111), Rh(111), Ir(111), and R...

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TL;DR: It is found that the electronic scattering process is spin-anisotropic; namely, the spin-down (up) transmittance channels are weakly (strongly) reduced by the presence of boron atoms, which can be controlled by the width of the nanoribbon.
Abstract: We report a spin polarized density functional theory study of the electronic and transport properties of graphene nanoribbons doped with boron atoms. We considered hydrogen terminated graphene (nano)ribbons with width up to 3.2 nm. The substitutional boron atoms at the nanoribbon edges (sites of lower energy) suppress the metallic bands near the Fermi level, giving rise to a semiconducting system. These substitutional boron atoms act as scattering centers for the electronic transport along the nanoribbons. We find that the electronic scattering process is spin-anisotropic; namely, the spin-down (up) transmittance channels are weakly (strongly) reduced by the presence of boron atoms. Such anisotropic character can be controlled by the width of the nanoribbon; thus, the spin-up and spin-down transmittance can be tuned along the boron-doped nanoribbons.

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26 Oct 2007-Science
TL;DR: Satellite observations showed a large-scale photosynthetic green-up in intact evergreen forests of the Amazon in response to a short, intense drought in 2005, suggesting that Amazon forests may be more resilient to climate changes than ecosystem models assume.
Abstract: Coupled climate-carbon cycle models suggest that Amazon forests are vulnerable to both long- and short-term droughts, but satellite observations showed a large-scale photosynthetic green-up in intact evergreen forests of the Amazon in response to a short, intense drought in 2005. These findings suggest that Amazon forests, although threatened by human-caused deforestation and fire and possibly by more severe long-term droughts, may be more resilient to climate changes than ecosystem models assume.

Journal Article
TL;DR: The findings of this study support previous research showing that tDCS is significantly associated with motor function improvement in stroke patients; and support that consecutive daily sessions of tDCS might increase its behavioral effects.
Abstract: Purpose: Recent evidence has suggested that a simple technique of noninvasive brain stimulation - transcranial direct current stimulation (tDCS) - is associated with a significant motor function improvement in stroke patients. Methods: We tested the motor performance improvement in stroke patients following 4 weekly sessions of sham, anodal- and cathodal tDCS (experiment 1) and the effects of 5 consecutive daily sessions of cathodal tDCS (experiment 2). A blinded rater evaluated motor function using the Jebsen-Taylor Hand Function Test. Results: There was a significant main effect of stimulation condition ( p = 0.009) in experiment 1. Furthermore there was a significant motor function improvement after either cathodal tDCS of the unaffected hemisphere ( p = 0.016) or anodal tDCS of the affected hemisphere (p = 0.046) when compared to sham tDCS. There was no cumulative effect associated with weekly sessions of tDCS, however consecutive daily sessions of tDCS (experiment 2) were associated with a significant effect on time ( p< 0.0001) that lasted for 2 weeks after treatment. Conclusions: The findings of our study support previous research showing that tDCS is significantly associated with motor function improvement in stroke patients; and support that consecutive daily sessions of tDCS might increase its behavioral effects. Because the technique of tDCS is simple, safe and non-expensive; our findings support further research on the use of this technique for the rehabilitation of patients with stroke.

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TL;DR: The treatment of OSA significantly improves early signs of Atherosclerosis, supporting the concept that OSA is an independent risk factor for atherosclerosis.
Abstract: Rationale: Obstructive sleep apnea (OSA) is associated with adverse cardiovascular outcomes, including myocardial infarction and stroke. Atherosclerosis is a key mechanism for these cardiovascular events. Recent cross-sectional studies showed the presence of early signs of atherosclerosis in patients with OSA who were free of comorbidities.Objectives: To determine the impact of treatment with continuous positive airway pressure (CPAP) on atherosclerosis.Methods: We randomly assigned 24 patients with severe OSA (age, 46 ± 6 yr) who were free of comorbidities to receive no treatment (control, n = 12) or CPAP (n = 12) for 4 months. Carotid intima-media thickness, arterial stiffness (evaluated by pulse-wave velocity), carotid diameter, 24-hour blood pressure monitoring, C-reactive protein, and catecholamines were determined at baseline and after 4 months.Measurements and Main Results: At baseline, all measurements were similar in both groups and did not change in the control group after 4 months. In contrast,...