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121.
Ferrer B Bermúdez-Silva FJ Bilbao A Alvarez-Jaimes L Sanchez-Vera I Giuffrida A Serrano A Baixeras E Khaturia S Navarro M Parsons LH Piomelli D Rodríguez de Fonseca F 《The Biochemical journal》2007,408(1):97-104
FgFtr1 and FgFtr2 are putative iron permeases, and FgFet1 and FgFet2 are putative ferroxidases of Fusarium graminearum. They have high homologies with iron permease ScFtr1 and ferroxidase ScFet3 of Saccharomyces cerevisiae at the amino acid level. The genes encoding iron permease and ferroxidase were localized to the same chromosome in the manner of FgFtr1/FgFet1 and FgFtr2/FgFet2. The GFP (green fluorescent protein)-fused versions of FgFtr1 and FgFtr2 showed normal functions when compared with FgFtr1 and FgFtr2 in an S. cerevisiae system, and the cellular localizations of FgFtr1 and FgFtr2 in S. cerevisiae depended on the expression of their putative ferroxidase partners FgFet1 and FgFet2 respectively. Although FgFtr1 was found on the plasma membrane when FgFet1 and FgFtr1 were co-transformed in S. cerevisiae, most of the FgFtr1 was found in the endoplasmic reticulum compartment when co-expressed with FgFet2. Furthermore, FgFtr2 was found on the vacuolar membrane when FgFet2 was co-expressed. From the two-hybrid analysis, we confirmed the interaction of FgFtr1 and FgFet1, and the same result was found between FgFtr2 and FgFet2. Iron-uptake activity also depended on the existence of the respective partner. Finally, the FgFtr1 and FgFtr2 were found on the plasma and vacuolar membrane respectively, in F. graminearum. Taken together, these results strongly suggest that FgFtr1 and FgFtr2 from F. graminearum encode the iron permeases of the plasma membrane and vacuolar membrane respectively, and require their specific ferroxidases to carry out normal function. Furthermore, the present study suggests that the reductive iron-uptake system is conserved from yeast to filamentous fungi. 相似文献
122.
Anderson S. Dias Jackson V. Araújo Artur K. Campos Fabio R. Braga Thiago A. Fonseca 《World journal of microbiology & biotechnology》2007,23(9):1245-1252
The viability of a formulation of Duddingtonia flagrans was assessed in the control of parasite gastrointestinal nematodes of cattle. Two groups (A and B) of eight crossbred Holstein × Zebu
cattle, approximately one year old, were placed in Brachiaria decumbens pasture. Each animal in group B (treated) received orally 20 g sodium alginate pellets containing mycelial mass of the D. flagrans fungus, while the animals in the group A (control) received pellets without fungus for seven months, starting in March 2005.
The egg per gram of feces counting the gastrointestinal nematodes showed a difference (P < 0.05) in the treated group in June, July and August, with reductions of 58% (June), 47% (July) and 51% (August) compared
to the control group. The infective larvae recovered in the pastures collected up to 20 cm from distance of the fecal dung
in group B differed (P < 0.01) from the larvae recovered in group A. At the end of the experimental period, the animals in group B presented a greater
weight gain (P < 0.01) compared to the untreated group (A). The treatment of cattle with pellets containing the D. flagrans nematophagous fungus, at the dose and duration used was effective in controlling the infective larvae of gastrointestinal
nematodes of cattle. 相似文献
123.
Susana Carvalho Joo Cúrdia Ana Moura Miguel B. Gaspar Maria Teresa Dinis Pedro Pouso-Ferreira Luís Cancela da Fonseca 《Acta Oecologica》2007,31(3):307-315
The present work evaluates the influence of fish production on macrobenthic colonization over large areas (approximately 700 m2), where the colonizing populations are not nearby the disturbed area. Sampling was undertaken within newly created aquaculture earthen ponds under two contrasting conditions: white seabream (Diplodus sargus) production and no production (control). Macrobenthic and geochemical samples were collected 7, 23, 54, 93 and 180 days after filling the earthen ponds with seawater pumped from a water reservoir for the first time. The water reservoir was also sampled, and is used as a reference for the colonizing populations. Macrobenthic colonization rate in the ponds was low, probably due to the isolation of the disturbed habitat, to the large size of the defaunated area, and possibly to geochemical constraints. Initial colonization was by insect larvae (mainly chironomids), the bivalves Cerastoderma spp., the polychaetes Pseudopolydora paucibranchiata and Hydrodoides elegans, and nemerteneans. The number of species was similar in control and production ponds, even though under production higher total abundance values were observed. Although well represented in the water reservoir, the amphipod Microdeutopus gryllotalpa was only observed within the new ponds after 6 months. Preliminary results suggest that macrobenthic colonization patterns were influenced by fish production, as assemblages were significantly different among ponds. Higher food availability due to fish production may explain the results obtained, but ecological reasons, such as predation, may also contribute for shaping the macrobenthic communities. 相似文献
124.
Rolim MF Riger CJ Eleutherio EC Colão Cda F Pereira GC Schanaider A 《Redox report : communications in free radical research》2007,12(6):267-274
This experimental study aimed to evaluate colon healing after portal ischemia followed by reperfusion. Seventy male Wistar rats randomly distributed in four groups were used: Group 1, colonic anastomosis (n = 20); Group 2, portal ischemia-reperfusion (n = 20); Group 3, colonic anastomosis and portal ischemia-reperfusion (n = 20); and Group 4, control (n = 10). In the postoperative period, these rats were re-allocated into subgroups and lipid peroxidation and protein oxidation plasma levels were evaluated on days 1 and 5 by thiobarbituric acid reactive substances (TBARS) and slot-blotting assays, respectively. A segment of the right colon was also removed for collagen analysis. Both malondialdehyde (MDA) and protein carbonyl levels (oxidative markers of lipids and proteins) presented a significant increase after reperfusion in Group 3 on days 1 (P < 0.002) and 5 (P < 0.0001). In this same group, an extensive inflammatory process showing decreased fibroplasia was observed, with deficiency in collagen deposition on both sides of the anastomosis edges. Taken together, these results indicate that portal congestion followed by reperfusion induces an oxidative stress, which impaired the mechanism of colon anastomotic healing. 相似文献
125.
Guedes HL Rezende JM Fonseca MA Salles CM Rossi-Bergmann B De-Simone SG 《Zeitschrift für Naturforschung. C, Journal of biosciences》2007,62(5-6):373-381
Leishmania (V) braziliensis is one of the most important ethiologic agents of the two distinct forms of American tegumentary leishmaniasis (cutaneous and mucosal). The drugs of choice used in leishmaniasis therapy are significantly toxic, expensive and are associated with frequent refractory infections. Among the promising new targets for anti-protozoan chemotherapy are the proteases. In this study, serine proteases were partially purified from aqueous, detergent and extracellular extracts of Leishmania braziliensis promastigotes by aprotinin-agarose affinity chromatography. By zymography, the enzymes purified from the aqueous extract showed apparent activity bands of 60 kDa and 45 kDa; of 130 kDa, 83 kDa, 74 kDa and 30 kDa from the detergent extract; and of 62 kDa, 59 kDa, 57 kDa, 49 kDa and 35 kDa from the extracellular extract. All purified proteases exhibited esterase activity against Nalpha-benzoyl-L-arginine ethyl ester hydrochloride and Nalpha-p-tosyl-L-arginine methyl ester hydrochloride (serine protease substrates) and optimal activity at pH 8. 0. Proteases purified from the aqueous and extracellular extracts were effectively inhibited by benzamidine (trypsin inhibitor) and those from the detergent extract were inhibited by N-tosyl-L-phenyl-alanine chloromethyl ketone (chymotrypsin inhibitor) indicating that all these enzymes are serine proteases. These findings indicate that L. braziliensis serine proteases display some biochemical similarities with L. amazonensis serine proteases, demonstrating a conservation of this enzymatic class in the Leishmania genus. This is the first study to report the purification of a serine protease from Leishmania braziliensis. 相似文献
126.
Sylvia Kamphuis Kolbrún Hrafnkelsdóttir Mark R Klein Wilco de Jager Margje H Haverkamp Jolanda HM van Bilsen Salvatore Albani Wietse Kuis Marca HM Wauben Berent J Prakken 《Arthritis research & therapy》2007,8(6):R178
Juvenile idiopathic arthritis (JIA) is a heterogeneous autoimmune disease characterized by chronic joint inflammation. Knowing
which antigens drive the autoreactive T-cell response in JIA is crucial for the understanding of disease pathogenesis and
additionally may provide targets for antigen-specific immune therapy. In this study, we tested 9 self-peptides derived from
joint-related autoantigens for T-cell recognition (T-cell proliferative responses and cytokine production) in 36 JIA patients
and 15 healthy controls. Positive T-cell proliferative responses (stimulation index ≥2) to one or more peptides were detected
in peripheral blood mononuclear cells (PBMC) of 69% of JIA patients irrespective of major histocompatibility complex (MHC)
genotype. The peptides derived from aggrecan, fibrillin, and matrix metalloproteinase (MMP)-3 yielded the highest frequency
of T-cell proliferative responses in JIA patients. In both the oligoarticular and polyarticular subtypes of JIA, the aggrecan
peptide induced T-cell proliferative responses that were inversely related with disease duration. The fibrillin peptide, to
our knowledge, is the first identified autoantigen that is primarily recognized in polyarticular JIA patients. Finally, the
epitope derived from MMP-3 elicited immune responses in both subtypes of JIA and in healthy controls. Cytokine production
in short-term peptide-specific T-cell lines revealed production of interferon-γ (aggrecan/MMP-3) and interleukin (IL)-17 (aggrecan)
and inhibition of IL-10 production (aggrecan). Here, we have identified a triplet of self-epitopes, each with distinct patterns
of T-cell recognition in JIA patients. Additional experiments need to be performed to explore their qualities and role in
disease pathogenesis in further detail. 相似文献
127.
Fonseca Bárbara Medeiros Câmara Paulo Eduardo Aguiar Saraiva Ogaki Mayara Baptistucci Pinto Otávio Henrique Bezerra Lirio Juan Manuel Coria Silvia H. Vieira Rosemary Carvalho-Silva Micheline Amorim Eduardo Toledo Convey Peter Rosa Luiz Henrique 《Molecular biology reports》2022,49(1):179-188
Molecular Biology Reports - Vega Island is located off the eastern tip of the Antarctic Peninsula (Maritime Antarctica), in the Weddell Sea. In this study, we used metabarcoding to investigate... 相似文献
128.
129.
Evaluation of blood pressure in feline night monkeys (Aotus azarae infulatus) under different restraint protocols
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130.
Stefania Neiva Lavorato Policarpo Ademar Sales Júnior Silvane Maria Fonseca Murta Alvaro José Romanha Ricardo José Alves/ 《Memórias do Instituto Oswaldo Cruz》2015,110(4):566-568
We describe herein the antitrypanosomal activity of 20 novel
1,3-bis(aryloxy)propan-2-amine derivatives. Compounds 2, 4, 6, 12, 15, 16 and 19 were
significantly active against amastigote and trypomastigote forms, with half maximal
inhibitory concentrationvalues in the range of 6-18 µM. In the cytotoxicity tests
against L929 cells, only compound 4 presented selectivity index value above 10,
indicating low toxicity. 相似文献