145 research outputs found

    Novel anticoagulant drugs

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    A presente revisão discute as características e o uso clínico potencial de novos agentes anticoagulantes, com ênfase para os inibidores dos fatores da coagulação IIa (trombina), IXa, Xa e FVIIa/fator tecidual, e para agentes que potencializam os mecanismos anticoagulantes e fibrinolíticos.The present review focuses on the characteristics and potential clinical use of new anticoagulant drugs, with emphasis on inhibitors of coagulation factors IIa (thrombin), IXa, Xa and VIIa/tissue factor, and on enhancers of anticoagulant and fibrinolytic activities

    Expanding The Knowledge On Lignocellulolytic And Redox Enzymes Of Worker And Soldier Castes From The Lower Termite Coptotermes Gestroi

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    Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Termites are considered one of the most efficient decomposers of lignocelluloses on Earth due to their ability to produce, along with its microbial symbionts, a repertoire of carbohydrate-active enzymes (CAZymes). Recently, a set of Pro-oxidant, Antioxidant, and Detoxification enzymes (PAD) were also correlated with the metabolism of carbohydrates and lignin in termites. The lower termite Coptotermes gestroi is considered the main urban pest in Brazil, causing damage to wood constructions. Recently, analysis of the enzymatic repertoire of C. gestroi unveiled the presence of different CAZymes. Because the gene profile of CAZy/PAD enzymes endogenously synthesized by C. gestroi and also by their symbiotic protists remains unclear, the aim of this study was to explore the eukaryotic repertoire of these enzymes in worker and soldier castes of C. gestroi. Our findings showed that worker and soldier castes present similar repertoires of CAZy/PAD enzymes, and also confirmed that endo-glucanases (GH9) and beta-glucosidases (GH1) were the most important glycoside hydrolase families related to lignocellulose degradation in both castes. Classical cellulases such as exo-glucanases (GH7) and endo-glucanases (GH5 and GH45), as well as classical xylanases (GH10 and GH11), were found in both castes only taxonomically related to protists, highlighting the importance of symbiosis in C. gestroi. Moreover, our analysis revealed the presence of Auxiliary Activity enzyme families (AAs), which could be related to lignin modifications in termite digestomes. In conclusion, this report expanded the knowledge on genes and proteins related to CAZy/PAD enzymes from worker and soldier castes of lower termites, revealing new potential enzyme candidates for second-generation biofuel processes.7FAPESP (The State of Sao Paulo Research Foundation) [11/20977-3, 15/06971-3, 12/19040-0, 14/10351-8, 06/59086-8, 14/20576-7, 13/03061-0, 10/11469-1]National Council for Scientific and Technological Development (CNPq) [140796/2013-4][08/58037-9][14/50371-8][08/50114-4][310186/2014-5][442333/2014-5]Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

    Leucemia linfocítica crônica: anormalidades cromossômicas e a sua relação com o estágio clínico CD38 e o ZAP-70

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    Chronic lymphocytic leukemia is the most prevalent type of leukemia in the West. It is characterized by an extremely variable clinical course. The aim of the study was to detect the most frequent chromosomal abnormalities in patients with CLL using FISH, and assess them regarding age, gender, clinical stage and CD38 and ZAP-70 expressions. We found 51.7% of the patients with chromosome abnormalities. The most frequent one was del 13q14 in 34.5% of cases. It was associated to other alterations in 17.2%. 17p13 deletions were found in 17.2% and trisomy 12 in 13.8% (in isolation in 6.9% and associated to del 13q14, in 6.9% of the cases). An 11q22 deletion was found in one case associated to a 13q14 deletion. To better evaluate the relationship between chromosome aberrations and other prognostic factors in CLL, two cytogenetics groups were considered: favorable (13q deletion in isolation and no alteration) and unfavorable outcomes (trisomy 12, 17p13 deletion, 11q22 deletion and two simultaneous alterations).The unfavorable alterations were more frequently seen among young individuals (<60y). There were more females (70%) than males in this group (p=0.04). In relation to the Binet's staging system, patients with unfavorable cytogenetic alterations, tended to be B and C stages, while in the favorable group prevailed patients in stage A. Additionally, patients with poor prognostic cytogenetics tended to express CD38 and ZAP-70 proteins.A leucemia linfocítica crônica (LLC) é o tipo de leucemia mais prevalente no Ocidente e é caracterizada por curso clínico extremamente variável. O objetivo deste estudo foi detectar as anomalias cromossômicas mais freqüentes em pacientes com LLC, empregando a técnica FISH, e correlacioná-las com idade, sexo, estádio clínico, expressão de CD 38 e ZAP-70. Foram encontradas alterações cromossômicas em 51,7% dos pacientes. A mais freqüente foi a del 13q14, observada em 34,5% dos casos e que esteve associada a outras anomalias em 17,2%. Deleção 17p13 foi encontrada em 17,2% e trissomia 12 em 13,8% (isolada em 6,9% e associada à del 13q14 em 6,9%). Deleção 11q22 foi observada em um caso em concomitância à del 13q14. Para melhor avaliar a relação entre alteração cromossômica e outros fatores prognósticos em LLC, dois grupos citogenéticos foram considerados: favorável (deleção 13q isolada e ausência de alterações) e desfavorável (trissomia 12, deleção 17p13, deleção 11q22 e duas anomalias simultâneas). As alterações desfavoráveis foram mais freqüentemente observadas em indivíduos jovens (<60 anos) e em mulheres (70%)(p=0,04). Em relação ao sistema de estadiamento de Binet, houve tendência dos pacientes com alterações cromossômicas desfavoráveis apresenteram-se nos estágios B e C enquanto no grupo favorável prevaleceram aqueles com estágio A. Em adição, pacientes com achados citogenéticos de prognóstico desfavorável tiveram tendência a expressar proteínas CD 38 e ZAP-70.Universidade Federal de São Paulo (UNIFESP) Escola Paulista de MedicinaUNIFESP, EPMSciEL

    Expanding the knowledge on lignocellulolytic and redox enzymes of worker and soldier castes from the lower termite coptotermes gestroi

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    Termites are considered one of the most efficient decomposers of lignocelluloses on Earth due to their ability to produce, along with its microbial symbionts, a repertoire of carbohydrate-active enzymes (CAZymes). Recently, a set of Pro-oxidant, Antioxidant, and Detoxification enzymes (PAD) were also correlated with the metabolism of carbohydrates and lignin in termites. The lower termite Coptotermes gestroi is considered the main urban pest in Brazil, causing damage to wood constructions. Recently, analysis of the enzymatic repertoire of C. gestroi unveiled the presence of different CAZymes. Because the gene profile of CAZy/PAD enzymes endogenously synthesized by C. gestroi and also by their symbiotic protists remains unclear, the aim of this study was to explore the eukaryotic repertoire of these enzymes in worker and soldier castes of C. gestroi. Our findings showed that worker and soldier castes present similar repertoires of CAZy/PAD enzymes, and also confirmed that endo-glucanases (GH9) and beta-glucosidases (GH1) were the most important glycoside hydrolase families related to lignocellulose degradation in both castes. Classical cellulases such as exo-glucanases (GH7) and endo-glucanases (GH5 and GH45), as well as classical xylanases (GH10 and GH11), were found in both castes only taxonomically related to protists, highlighting the importance of symbiosis in C. gestroi. Moreover, our analysis revealed the presence of Auxiliary Activity enzyme families (AAs), which could be related to lignin modifications in termite digestomes. In conclusion, this report expanded the knowledge on genes and proteins related to CAZy/PAD enzymes from worker and soldier castes of lower termites, revealing new potential enzyme candidates for second-generation biofuel processes7CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP140796/2013-4; 310186/2014-5; 442333/2014-511/20977-3; 15/06971-3; 12/19040-0; 14/10351-8; 06/59086-8; 14/20576- 7; 13/03061-0; 10/11469-1; 08/58037-9; 14/50371-8; 08/50114-

    Acceleration of methane production by carbon nanotubes

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    Book of Abstracts of CEB Annual Meeting 2017[Excerpt] Carbon nanotubes and other conductive materials have been found to influence the rates of several anaerobic reactions. A range of different conductive carbon materials (CM) were reported to enhance methane production by anaerobic microbial communities. In most studies, the improvement of the overall process is attributed to the ability of these compounds to promote direct interspecies electron transfer (DIET) between bacteria, degrading more complex substrates, and methanogens, producing methane. The occurrence of DIET in the majority of these systems is not, however, proved and the effect of such conductive compounds on the activity of individual members, inside complex microbial communities, was never investigated. Thus, we herein present the results obtained when incubating pure cultures of methanogens, without any other microbial partner, in the presence of increasing concentrations of carbon nanotubes (CNT). Methane production from acetate, by the acetoclastic methanogens Methanosaeta concilii and Methanosarcina mazei, and from hydrogen plus carbon dioxide, by the hydrogenotrophic methanogens Methanospirillum hungatei and Methanobacterium formicicum, was accelerated, up to 17 times, in the presence of CNT [1]. Physical/chemical properties of the growth media changed in the presence of CNT, with redox potential decreasing with increasing CNT concentrations, and thus favouring methanogenesis. These findings show that CNT influences the microbial activity of methanogens in pure cultures and most likely this effect is extended to methanogens in complex communities as well, occurring in anaerobic bioreactors and in the environment. [...]info:eu-repo/semantics/publishedVersio

    The MHC Gene Region of Murine Hosts Influences the Differential Tissue Tropism of Infecting Trypanosoma cruzi Strains

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    We have previously demonstrated that both parasite genetic variability and host genetic background were important in determining the differential tissue distribution of the Col1.7G2 and JG T. cruzi monoclonal strains after artificial infections in mice. We observed that the JG strain was most prevalent in hearts of mouse lineages with the MHC haplotype H-2d (BALB/c and DBA2), while Col1.7G2 was predominant in hearts from C57BL/6 mice, which have the H-2b haplotype. To assess whether the MHC gene region indeed influenced tissue tropism of T. cruzi, we used the same two parasite strains to infect C57BL/6 (H-2b) and C57BLKS/J (H-2d) mice; the latter strain results from the introgression of DBA2 MHC region into the C57BL/6 background. We also performed ex vivo infections of cardiac explants from four congenic mice lineages with the H-2b and H-2d haplotypes arranged in two different genetic backgrounds: C57BLKS/J (H-2d) versus C57BL/6 (H-2b) and BALB/c (H-2d) versus BALB/B10-H2b (H-2b). In agreement with our former observations, Col1.7G2 was predominant in hearts from C57BL/6 mice (H-2b), but we observed a clear predominance of the JG strain in hearts from C57BLKS/J animals (H-2d). In the ex vivo experiments Col1.7G2 also prevailed in explants from H-2b animals while no predominance of any of the strains was observed in H-2d mice explants, regardless of the genetic background. These observations clearly demonstrate that the MHC region influences the differential tissue distribution pattern of infecting T. cruzi strains, which by its turn may be in a human infection the determinant for the clinical forms of the Chagas disease

    On the roles of AA15 lytic polysaccharide monooxygenases derived from the termite Coptotermes gestroi

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    Lytic polysaccharide monooxygenases (LPMOs) are copper-dependent enzymes which catalyze the oxidative cleavage of polysaccharides. LPMOs belonging to family 15 in the Auxiliary Activity (AA) class from the Carbohydrate-Active Enzyme database are found widespread across the Tree of Life, including viruses, algae, oomycetes and animals. Recently, two AA15s from the firebrat Thermobia domestica were reported to have oxidative activity, one towards cellulose or chitin and the other towards chitin, signalling that AA15 LPMOs from insects potentially have different biochemical functions. Herein, we report the identification and characterization of two family AA15 members from the lower termite Coptotermes gestroi. Addition of Cu(II) to CgAA15a or CgAA15b had a thermostabilizing effect on both. Using ascorbate and O2 as co-substrates, CgAA15a and CgAA15b were able to oxidize chitin, but showed no activity on celluloses, xylan, xyloglucan and starch. Structural models indicate that the LPMOs from C. gestroi (CgAA15a/CgAA15b) have a similar fold but exhibit key differences in the catalytic site residues when compared to the cellulose/chitin-active LPMO from T. domestica (TdAA15a), especially the presence of a non-coordinating phenylalanine nearby the Cu ion in CgAA15a/b, which appears as a tyrosine in the active site of TdAA15a. Despite the overall similarity in protein folds, however, mutation of the active site phenylalanine in CgAA15a to a tyrosine did not expanded the enzymatic specificity from chitin to cellulose. Our data show that CgAA15a/b enzymes are likely not involved in lignocellulose digestion but might play a role in termite developmental processes as well as on chitin and nitrogen metabolisms

    Tropical and Boreal Forest Atmosphere Interactions: A Review

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    This review presents how the boreal and the tropical forests affect the atmosphere, its chemical composition, its function, and further how that affects the climate and, in return, the ecosystems through feedback processes. Observations from key tower sites standing out due to their long-term comprehensive observations: The Amazon Tall Tower Observatory in Central Amazonia, the Zotino Tall Tower Observatory in Siberia, and the Station to Measure Ecosystem-Atmosphere Relations at Hyytiala in Finland. The review is complemented by short-term observations from networks and large experiments.The review discusses atmospheric chemistry observations, aerosol formation and processing, physiochemical aerosol, and cloud condensation nuclei properties and finds surprising similarities and important differences in the two ecosystems. The aerosol concentrations and chemistry are similar, particularly concerning the main chemical components, both dominated by an organic fraction, while the boreal ecosystem has generally higher concentrations of inorganics, due to higher influence of long-range transported air pollution. The emissions of biogenic volatile organic compounds are dominated by isoprene and monoterpene in the tropical and boreal regions, respectively, being the main precursors of the organic aerosol fraction.Observations and modeling studies show that climate change and deforestation affect the ecosystems such that the carbon and hydrological cycles in Amazonia are changing to carbon neutrality and affect precipitation downwind. In Africa, the tropical forests are so far maintaining their carbon sink.It is urgent to better understand the interaction between these major ecosystems, the atmosphere, and climate, which calls for more observation sites, providing long-term data on water, carbon, and other biogeochemical cycles. This is essential in finding a sustainable balance between forest preservation and reforestation versus a potential increase in food production and biofuels, which are critical in maintaining ecosystem services and global climate stability. Reducing global warming and deforestation is vital for tropical forests
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