578 research outputs found
The impact of globalisation on the position of developing countries in the international tax system
The objective of this thesis is to analyse the relationship between international taxation
and developing countries. The main idea is to examine this relationship through
arguments that challenge the current legal debate that has described their interest as
capital importers of foreign direct investment.
Globalisation has changed the economic relations between developed and developing
countries. The evolution of the economic aspects as well as tax policies implemented
during the process of globalisation provides the background necessary to understand the
increased importance of international taxation and the participation of developing
countries in the global economy.
The hypothesis tested here addresses the question whether the dichotomy between
developing and developed countries and their characterisation as capital importers and
capital exporters still provides an appropriate basis for the legal debate on international
taxation in the context of globalisation. To approach this question, the behaviour of
international flow of capital will be assessed in order to provide an overview of the
economic relations among these countries.
To perform this study, initially the meaning of globalisation and international taxation
are explained in order to build up the framework of this thesis; secondly, the current
debate on harmful tax competition is examined to put in evidence the problem addressed
in this thesis; thirdly, an analysis of the international flow of capital is performed to
identify new premises that could update the legal debate; fourthly, based on the profile
of the international flow of capital, the phenomenon of capital flight is addressed.
Fifthly, having in mind the difficulty in taxing capital flight, taxation of portfolio
investment is examined. Based on the arguments raised, the legal debate is updated
demonstrating the higher importance of double taxation over tax avoidance and evasion
in the recent past. Finally, considering the increased relevance of international tax
avoidance and evasion, instruments available for exchange of information are analysed,
and their effectiveness to curb capital flight from developing countries
Impact of paracoccin gene silencing on Paracoccidioides brasiliensis Virulence
Among the endemic deep mycoses in Latin America, paracoccidioidomycosis (PCM), caused by thermodimorphic fungi of the Paracoccidioides genus, is a major cause of morbidity. Disease development and its manifestations are associated with both host and fungal factors. Concerning the latter, several recent studies have employed the methodology of gene modulation in P. brasiliensis using antisense RNA (AsRNA) and Agrobacterium tumefaciens-mediated transformation (ATMT) to identify proteins that influence fungus virulence. Our previous observations suggested that paracoccin (PCN), a multidomain fungal protein with both lectin and enzymatic activities, may be a potential P. brasiliensis virulence factor. To explore this, we used AsRNA and ATMT methodology to obtain three independent PCN-silenced P. brasiliensis yeast strains (AsPCN1, AsPCN2, and AsPCN3) and characterized them with regard to P. brasiliensis biology and pathogenicity. AsPCN1, AsPCN2, and AsPCN3 showed relative PCN expression levels that were 60%, 40%, and 60% of that of the wild-type (WT) strain, respectively. PCN silencing led to the aggregation of fungal cells, blocked the morphological yeast-to-mycelium transition, and rendered the yeast less resistant to macrophage fungicidal activity. In addition, mice infected with AsPCN1, AsPCN2, and AsPCN3 showed a reduction in fungal burden of approximately 96% compared with those inoculated with the WT strain, which displayed a more extensive destruction of lung tissue. Finally, mice infected with the PCN-silenced yeast strains had lower mortality than those infected with the WT strain. These data demonstrate that PCN acts as a P. brasiliensis contributory virulence factor directly affecting fungal pathogenesis. IMPORTANCE The nonexistence of efficient genetic transformation systems has hampered studies in the dimorphic fungus Paracoccidioides brasiliensis, the etiological agent of the most frequent systemic mycosis in Latin America. The recent development of a method for gene expression knockdown by antisense RNA technology, associated with an Agrobacterium tumefaciens-mediated transformation system, provides new strategies for studying P. brasiliensis. Through this technology, we generated yeasts that were silenced for paracoccin (PCN), a P. brasiliensis component that has lectin and enzymatic properties. By comparing the phenotypes of PCN-silenced and wild-type strains of P. brasiliensis, we identified PCN as a virulence factor whose absence renders the yeasts unable to undergo the transition to mycelium and causes a milder pulmonary disease in mice, with a lower mortality rate. Our report highlights the importance of the technology used for P. brasiliensis transformation and demonstrates that paracoccin is a virulence factor acting on fungal biology and pathogenesis.This work had financial support from the following agencies: Fundação de Amparo à Pesquisa do Estado de São Paulo – FAPESP (2016/00629-4, 2014/05359-0, 2012/08552-0, 2014/22561-7, 2012/09611-0, 2016/04877-2, 2016/60642-2, and 2013/04088-0); Conselho Nacional de Desenvolvimento Científico e Tecnológico – CNPq (150036/2014-0, 477161/2008-1, and 475357/2013-2); Financiadora de Estudos e Projetos – FINEP (0110045900); Ministry of Education and Science – Fundação para a Ciência e a Tecnologia – FCT (SFRH/BPD/96176/2013 and IF/00735/2014)info:eu-repo/semantics/publishedVersio
TLR9 activation dampens the early inflammatory response to paracoccidioides brasiliensis, Impacting host survival
Background: Paracoccidioides brasiliensis causes paracoccidioidomycosis, one of the most prevalent systemic mycosis in
Latin America. Thus, understanding the characteristics of the protective immune response to P. brasiliensis is of interest, as it
may reveal targets for disease control. The initiation of the immune response relies on the activation of pattern recognition
receptors, among which are TLRs. Both TLR2 and TLR4 have been implicated in the recognition of P. brasiliensis and
regulation of the immune response. However, the role of TLR9 during the infection by this fungus remains unclear.J.F. Menino was supported by a grant from Fundacao para a Ciencia e Tecnologia (FCT), Portugal (SFRH/BD/33446/2008). This work was supported by a grant from FCT (PTDC/BIA-MIC/108309/2008). M. Saraiva is a Ciencia 2007 fellow and M. Sturme is a Ciencia 2008 fellow. We would also like to thank FAPESP (Fundacao para Amparo a Pesquisa do Estado de Sao Paulo) and CNPq (Conselho Nacional de Desenvolvimento Cientifico e Tecnologico) for financial support. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript
Pulmonary paracoccidioidomycosis in AhR deficient hosts is severe and associated with defective Treg and Th22 responses
© The Author(s) 2020. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.AhR is a ligand-activated transcription factor that plays an important role in the innate and adaptive immune responses. In infection models, it has been associated with host responses that promote or inhibit disease progression. In pulmonary paracoccidioidomycosis, a primary fungal infection endemic in Latin America, immune protection is mediated by Th1/Th17 cells and disease severity with predominant Th2/Th9/Treg responses. Because of its important role at epithelial barriers, we evaluate the role of AhR in the outcome of a pulmonary model of paracoccidioidomycosis. AhR-/- mice show increased fungal burdens, enhanced tissue pathology and mortality. During the infection, AhR-/- mice have more pulmonary myeloid cells with activated phenotype and reduced numbers expressing indoleamine 2,3 dioxygenase 1. AhR-deficient lungs have altered production of cytokines and reduced numbers of innate lymphoid cells (NK, ILC3 and NCR IL-22). The lungs of AhR-/- mice showed increased presence Th17 cells concomitant with reduced numbers of Th1, Th22 and Foxp3+ Treg cells. Furthermore, treatment of infected WT mice with an AhR-specific antagonist (CH223191) reproduced the main findings obtained in AhR-/- mice. Collectively our data demonstrate that in pulmonary paracoccidioidomycosis AhR controls fungal burden and excessive tissue inflammation and is a possible target for antifungal therapy.This work was supported by a grant from the Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP-grant to VLGC 2011/51258-2 and 2016/23189-0; fellowship to EFA 2014/18668-2; grant to FVL 2018/14762-3; fellowship to NWP 2019-09278-8), European Union H2020 ERA project (No 667824 – EXCELLtoINNOV) to MV and Conselho Nacional de Pesquisas (CNPq).info:eu-repo/semantics/publishedVersio
Comparative Genomic Analysis of Human Fungal Pathogens Causing Paracoccidioidomycosis
Paracoccidioides is a fungal pathogen and the cause of paracoccidioidomycosis, a health-threatening human systemic mycosis endemic to Latin America. Infection by Paracoccidioides, a dimorphic fungus in the order Onygenales, is coupled with a thermally regulated transition from a soil-dwelling filamentous form to a yeast-like pathogenic form. To better understand the genetic basis of growth and pathogenicity in Paracoccidioides, we sequenced the genomes of two strains of Paracoccidioides brasiliensis (Pb03 and Pb18) and one strain of Paracoccidioides lutzii (Pb01). These genomes range in size from 29.1 Mb to 32.9 Mb and encode 7,610 to 8,130 genes. To enable genetic studies, we mapped 94% of the P. brasiliensis Pb18 assembly onto five chromosomes. We characterized gene family content across Onygenales and related fungi, and within Paracoccidioides we found expansions of the fungal-specific kinase family FunK1. Additionally, the Onygenales have lost many genes involved in carbohydrate metabolism and fewer genes involved in protein metabolism, resulting in a higher ratio of proteases to carbohydrate active enzymes in the Onygenales than their relatives. To determine if gene content correlated with growth on different substrates, we screened the non-pathogenic onygenale Uncinocarpus reesii, which has orthologs for 91% of Paracoccidioides metabolic genes, for growth on 190 carbon sources. U. reesii showed growth on a limited range of carbohydrates, primarily basic plant sugars and cell wall components; this suggests that Onygenales, including dimorphic fungi, can degrade cellulosic plant material in the soil. In addition, U. reesii grew on gelatin and a wide range of dipeptides and amino acids, indicating a preference for proteinaceous growth substrates over carbohydrates, which may enable these fungi to also degrade animal biomass. These capabilities for degrading plant and animal substrates suggest a duality in lifestyle that could enable pathogenic species of Onygenales to transfer from soil to animal hosts.National Institute of Allergy and Infectious Diseases (U.S.)National Institutes of Health. Department of Health and Human Services (contract HHSN266200400001C)National Institutes of Health. Department of Health and Human Services(contract HHSN2722009000018C)Brazil. National Council for Scientific and Technological Developmen
Cardiac autonomic impairment and chronotropic incompetence in fibromyalgia
Abstract\ud
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Introduction\ud
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We aimed to gather knowledge on the cardiac autonomic modulation in patients with fibromyalgia (FM) in response to exercise and to investigate whether this population suffers from chronotropic incompetence (CI).\ud
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Methods\ud
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Fourteen women with FM (age: 46 ± 3 years; body mass index (BMI): 26.6 ± 1.4 kg/m2) and 14 gender-, BMI- (25.4 ± 1.3 kg/m2), and age-matched (age: 41 ± 4 years) healthy individuals (CTRL) took part in this cross-sectional study. A treadmill cardiorespiratory test was performed and heart-rate (HR) response during exercise was evaluated by the chronotropic reserve. HR recovery (deltaHRR) was defined as the difference between HR at peak exercise and at both first (deltaHRR1) and second (deltaHRR2) minutes after the exercise test.\ud
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Results\ud
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FM patients presented lower maximal oxygen consumption (VO2 max) when compared with healthy subjects (22 ± 1 versus CTRL: 32 ± 2 mL/kg/minute, respectively; P < 0.001). Additionally, FM patients presented lower chronotropic reserve (72.5 ± 5 versus CTRL: 106.1 ± 6, P < 0.001), deltaHRR1 (24.5 ± 3 versus CTRL: 32.6 ± 2, P = 0.059) and deltaHRR2 (34.3 ± 4 versus CTRL: 50.8 ± 3, P = 0.002) than their healthy peers. The prevalence of CI was 57.1% among patients with FM.\ud
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Conclusions\ud
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Patients with FM who undertook a graded exercise test may present CI and delayed HR recovery, both being indicative of cardiac autonomic impairment and higher risk of cardiovascular events and mortality.This work was supported by the Fundação de Amparo a Pesquisa do Estado de São Paulo (Grant 2009/51897-5)
O PAPEL DO BRASIL COMO INDUTOR DO PROCESSO DE INTEGRAÇÃO ENERGÉTICA REGIONAL NA AMÉRICA DO SUL
O presente artigo tem como objetivo analisar qual o papel do Brasil como indutor do processo de integração energética regional na América do Sul. Tem-se como hipótese que o Brasil exerce função de liderança na integração energética sul-americana. Destaca-se, para tal, o papel do Conselho Energético Sul-Americano (UNASUL), da Petrobrás e da integração via hidrelétricas no subcontinente sul-americano. Entretanto, ainda são identificadas diversas dificuldades e insuficiências, como a ausência de um marco regulatório, a falta de capacidade de financiamento e a falta de medidas tomadas no âmbito multilateral para a conquista de uma integração energética efetiva na América do Sul
TLR2 Is a Negative Regulator of Th17 Cells and Tissue Pathology in a Pulmonary Model of Fungal Infection
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