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101.
Hokeness-Antonelli KL Crane MJ Dragoi AM Chu WM Salazar-Mather TP 《Journal of immunology (Baltimore, Md. : 1950)》2007,179(9):6176-6183
Chemokine responses critical for inflammation and promotion of effective innate control of murine CMV (MCMV) in liver have been shown to be dependent on immunoregulatory functions elicited by IFN-alphabeta. However, it remains to be determined whether upstream factors that promote viral sensing resulting in the rapid secretion of IFN-alphabeta in liver differ from those described in other tissues. Because plasmacytoid dendritic cells (pDCs) are known producers of high levels of systemic IFN-alpha in response to MCMV, this study examines the in vivo contribution of pDCs to IFN-alpha production in the liver, and whether production of the cytokine and ensuing inflammatory events are dependent on TLR9, MyD88, or both. We demonstrate that whereas MyD88 deficiency markedly impaired secretion of IFN-alpha, production of the cytokine was largely independent of TLR9 signaling, in the liver. MyD88 and TLR9 were needed for IFN-alpha production in the spleen. Moreover, hepatic but not splenic pDCs produced significant amounts of intracellular IFN-alpha in the absence of TLR9 function during infection. Furthermore, production of CCL2, CCL3, and IFN-gamma, as well as the accumulation of macrophages and NK cells, was not affected in the absence of functional TLR9 in the liver. In contrast, these responses were dramatically reduced in MyD88(-/-) mice. Additionally, MyD88(-/-) but not TLR9(-/-) mice exhibited increased sensitivity to virus infection in liver. Collectively, our results define contrasting compartmental functions for TLR9 and MyD88, and suggest that the infected tissue site uniquely contributes to the process of virus sensing and regulation of localized antiviral responses. 相似文献
102.
Tiago M. S. Freitas Ana Thais T. De Paula Híngara Leo Naraiana L. Benone Luciano F. A. Montag 《Zeitschrift fur angewandte Ichthyologie》2019,35(3):793-795
The present study shows the length–weight relationships (LWR) for 11 stream fish species from Anapu River Basin, in eastern Amazon, Pará State, Brazil. Samplings were carried out in October and November 2010, 2012 and 2013, and fishes were collected using hand nets of 55 cm of diameter and 2 mm mesh size. Fixed specimens were measured for standard length (cm) and total weight (g). Allometric coefficients b varied from 2.606 to 3.335 and coefficients of determination (R2) varied from 0.902 to 0.986. Shrinkage effect must be considered in future investigations in order to provide a correction factor. 相似文献
103.
Drought Tolerance Conferred to Sugarcane by Association with Gluconacetobacter diazotrophicus: A Transcriptomic View of Hormone Pathways 总被引:1,自引:0,他引:1
104.
Glucocorticoid and estrogen receptors are reduced in mitochondria of lung epithelial cells in asthma
Mitochondrial glucocorticoid (mtGR) and estrogen (mtER) receptors participate in the coordination of the cell's energy requirement and in the mitochondrial oxidative phosphorylation enzyme (OXPHOS) biosynthesis, affecting reactive oxygen species (ROS) generation and induction of apoptosis. Although activation of mtGR and mtER is known to trigger anti-inflammatory signals, little information exists on the presence of these receptors in lung tissue and their role in respiratory physiology and disease. Using a mouse model of allergic airway inflammation disease and applying confocal microscopy, subcellular fractionation, and Western blot analysis we showed mitochondrial localization of GRα and ERβ in lung tissue. Allergic airway inflammation caused reduction in mtGRα, mtERβ, and OXPHOS enzyme biosynthesis in lung cells mitochondria and particularly in bronchial epithelial cells mitochondria, which was accompanied by decrease in lung mitochondrial mass and induction of apoptosis. Confirmation and validation of the reduction of the mitochondrial receptors in lung epithelial cells in human asthma was achieved by analyzing autopsies from fatal asthma cases. The presence of the mitochondrial GRα and ERβ in lung tissue cells and especially their reduction in bronchial epithelial cells during allergic airway inflammation suggests a crucial role of these receptors in the regulation of mitochondrial function in asthma, implicating their involvement in the pathophysiology of the disease. 相似文献
105.
Lima FC Viana RB da Silva TT Wardell SM do Filho AP Carneiro JW Comar M da Silva AB 《Journal of molecular modeling》2012,18(7):3243-3253
A theoretical study of structures of the 1,7,1 l,17-tetraoxa-2,6,12,16-tetraaza-cycloeicosane ligand ([20]AneN(4)O(4)) coordinated to Fe(2+), Co(2+), Ni(2+), Ru(2+), Rh(2+), and Pd(2+) transition metals ions was carried out with the DFT/B3LYP method. Complexes were fully optimized in C(s) symmetry with the metal ions coordinated either to nitrogen (1a) or oxygen atoms (1b). For all the cases performed in this work, 1a was always more stable than 1b. Considering each row it is possible to see that the binding energy increases with the atomic number. The M(2+) cation binding energies increase in the following order: Fe(2+)相似文献
106.
Simone Quintana de Oliveira Maria Tereza Rojo de Almeida Flora Maraslis Izabella Thaís Silva Thais Cristine Marques Sincero Jorge Alejandro Palermo Gabriela Myriam Cabrera Miguel Soriano Balparda Caro Cláudia Maria Oliveira Simões Eloir Paulo Schenkel 《Phytochemistry letters》2012,5(3):500-505
Investigation of the crude ethanolic extract obtained from the aerial parts of Dodonaea viscosa led to the isolation of three new ent-labdane diterpenes (1–3). The structures were established on the basis of their ESI–MS, UV, IR and NMR spectral data. The crude extract, fractions and compounds were evaluated for in vitro antiviral activity against Herpes Simplex Virus type 1 (HSV-1). The crude extract showed promising antiherpes activity expressed by a selectivity index of 6.2. 相似文献
107.
Parasite levels in blue-black grassquits correlate with male displays but not female mate preference
Aguilar Thais M.; Maia Rafael; Santos Eduardo S.A.; Macedo Regina H. 《Behavioral ecology》2008,19(2):292-301
The handicap principle proposes that male sexual ornaments anddisplays provide honest indicators of quality. Female preferencefor high-quality males, however, may be driven not only by geneticbenefits but also by indirect benefits. We investigated theimpact of parasitism on morphological, ornamental, and behavioralcharacteristics of male and female blue-black grassquits (Volatiniajacarina) in captivity. First, we tested whether male displaysand morphology were influenced by parasitism. Second, we assessedif females were attentive to variation in male morphology anddisplays linked to parasitism. Third, we tested whether parasitismin females influenced health and mate preferences. We maintained2 groups of birds in captivity: nonmedicated birds developedhigh levels of coccidian parasitism, whereas medicated birdswere free of parasitism. Parasitized males developed, relativeto nonparasitized males, lower weight/tarsus indices and mass.They also showed relative deficiencies in their displays, withless persistence and lower rates. Despite the negative effectsof parasitism on males, females did not prefer nonparasitizedmales. This held for both parasitized and nonparasitized females.Our data suggest that coccidian parasitism has adverse effectson morphological condition and expression of displays. Theseeffects, however, appear not to be attended to by females; moreover,female mate preferences appear not to be impacted by the threatof parasitism. It thus seems that female mate preferences maynot depend only on sexual characters affected by parasitismin this species. 相似文献
108.
Expression of matrix metalloproteinases-2 and -9 and RECK during alveolar bone regeneration in rat 总被引:1,自引:0,他引:1
Accorsi-Mendonça T Paiva KB Zambuzzi WF Cestari TM Lara VS Sogayar MC Taga R Granjeiro JM 《Journal of molecular histology》2008,39(2):201-208
MMPs are endopeptidases that play a pivotal role in ECM turnover. RECK is a single membrane-anchored MMP-regulator. Here,
we evaluated the temporal and spatial expression of MMP-2, MMP-9, and RECK during alveolar bone regeneration. The maxillary
central incisor of Wistar rats was extracted and the animals were killed at 1, 3, 7, 10, 14, 21, 28, and 42 days post-operatively
(n = 3/period). The hemimaxillae were collected, demineralized and embedded in paraffin. Immunohistochemical analysis was performed
by the immunoperoxidase technique with polyclonal antibodies. On day 1, polymorphonuclear cells in the blood clot presented
mild immunolabeling for MMPs. During bone remodeling, osteoblasts facing new bone showed positive staining for gelatinases
and RECK in all experimental periods. MMPs were also found in the connective tissue and endothelial cells. Our results show
for the first time that inactive and/or active forms of MMP-2, MMP-9 and RECK are differentially expressed by osteogenic and
connective cells during several events of alveolar bone regeneration. This may be important for the replacement of the blood
clot by connective tissue, and in the formation, maturation and remodeling of new bone. 相似文献
109.
Kempka AP Lipke NL da Luz Fontoura Pinheiro T Menoncin S Treichel H Freire DM Di Luccio M de Oliveira D 《Bioprocess and biosystems engineering》2008,31(2):119-125
Current studies about lipase production by solid-state fermentation involve the use of agro-industrial residues towards developing
cost-effective systems directed to large-scale commercialization of enzyme-catalyzed processes. In this work, lipase production
and partial characterization of the crude enzymatic extracts obtained by Penicillium verrucosum using soybean bran as substrate was investigated. Different inductors were evaluated and the results showed that there is
no influence of this variable on the lipase production, while temperature and initial moisture were the main factors that
affected enzyme production. The optimized cultivation temperature (27.5 °C) and initial moisture of substrate (55%) were determined
using the response surface methodology. Kinetics of lipase production was followed at the optimized growth conditions. Optimum
lipase yield was 40 U/g of dry bran. The crude enzymatic extract showed optimal activity in the range from 30 to 45 °C and
in pH 7.0. 相似文献
110.
Marcia Perez Dos Santos Cabrera Manoel Arcisio‐Miranda Sabrina Thais Broggio Costa Katsuhiro Konno José Roberto Ruggiero Joaquim Procopio João Ruggiero Neto 《Journal of peptide science》2008,14(6):661-669
Anoplin, an antimicrobial, helical decapeptide from wasp venom, looses its biological activities by mere deamidation of its C-terminus. Secondary structure determination, by circular dichroism spectroscopy in amphipathic environments, and lytic activity in zwitterionic and anionic vesicles showed quite similar results for the amidated and the carboxylated forms of the peptide. The deamidation of the C-terminus introduced a negative charge at an all-positive charged peptide, causing a loss of amphipathicity, as indicated by molecular dynamics simulations in TFE/water mixtures and this subtle modification in a peptide's primary structure disturbed the interaction with bilayers and biological membranes. Although being poorly lytic, the amidated form, but not the carboxylated, presented ion channel-like activity on anionic bilayers with a well-defined conductance step; at approximately the same concentration it showed antimicrobial activity. The pores remain open at trans-negative potentials, preferentially conducting cations, and this situation is equivalent to the interaction of the peptide with bacterial membranes that also maintain a high negative potential inside. 相似文献