1000 resultados para Porto Vivo SRU
Resumo:
Seed extracts of Aphanamixis polystachya Wall et Parker (pithraj) and Azadirachta indica A. Juss (neem) were evaluated for their in vivo and in vitro toxicity to Nephotettix cincticeps Uhler (rice green leafhopper). Crude extracts from both plants showed toxicity to leafhopper. Among them, the methanol extract of pithraj (MCX) was most toxic and showed 95% mortality effects at 72 h after treatment (HAT), followed by neem (74%). When LD50's were compared, it was found that the neem extract possessed the highest toxicity (LD50 16.59 μg/insect) at 72 HAT. Both the pithraj (MCX) and neem extracts showed their enzyme inhibition effectiveness against rice green leafhopper. The highest inhibition rate (IR) was caused by neem (60%) at the concentration of 2.0 mg/ml, followed by MCX (47%). The lowest IR50 value (0.97 mg/ml) was observed in neem at 30 min.
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Objective: To examine whether NKP608, a novel 1-benzoyl-2-benzyl-4-aminopiperidine NK1 receptor antagonist, inhibits substance P (SP)-induced airway plasma protein exudation in vivo. Material: Anaesthetised English shorthair guinea-pigs and Wistar rats. Treatment: Tachykinin peptides were applied topically onto the trachea and antagonists administered intravenously. Methods: Tracheal segments isolated in situ were perfused with saline and plasma-derived protein assayed in the perfusate. Results: SP (1 muM) caused plasma protein exudation, which was abolished by an NK1 antagonist (RP 67580, 1.75 mumol/kg) but unaffected by an NK2 antagonist (SR 48968, 1.75 mumol/kg) indicating the response is NK1-receptor-mediated. This was confirmed with a response to an NK1 agonist ([Sar(9), Met(O-2)(11)]-SP, 1 muM) but none to an NK2 agonist ([betaAla(8)]-neurokinin A(4-10), 1 muM). NKP608 inhibited SP responses with estimated ID50 values (mumol/kg) of 0.0044 (guinea-pigs) and 0.19 (rats). Conclusions: NKP608 is an antagonist in vivo of NK1 receptor-induced tracheal plasma protein exudation and is more potent in guinea-pigs than rats.
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RT-PCR followed by 5'- and 3'- rapid amplification of cDNA ends was used to clone and sequence ovine prolactin-releasing peptide (PrRP). The cDNA was characterised by short 5'- and 3'-untranslated regions and a GC-rich (71%) coding region. The nucleotide and deduced amino acid sequences for the coding region showed 95.6 and 94.9% identity with bovine PrRP but the amino acid sequence of PrRP31 was conserved between these species. Northern blot analysis and RT-PCR showed that, as in the rat, the peptide was more abundantly expressed in the brainstem than the hypothalamus. However, in the ovine hypothalamus, PrRP mRNA expression was more widespread than in the rat, with expression detected in both rostral and caudal parts of the mediobasal hypothalamus. The effects of synthetic ovine PrRP on prolactin secretion both in vitro and in vivo were also examined. In primary cultures of sheep pituitary cells, PrRP significantly (P
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Random mutagenesis and genetic screens for impaired Raf function in Caenorhabditis elegans were used to identify six loss-of-function alleles of lin-45 raf that result in a substitution of a single amino acid. The mutations were classified as weak, intermediate, and strong based on phenotypic severity. We engineered these mutations into the homologous residues of vertebrate Raf-1 and analyzed the mutant proteins for their underlying biochemical defects. Surprisingly, phenotype strength did not correlate with the catalytic activity of the mutant proteins. Amino acid substitutions Val-589 and Ser-619 severely compromised Raf kinase activity, yet these mutants displayed weak phenotypes in the genetic screen. Interestingly, this is because these mutant Raf proteins efficiently activate the MAPK (mitogen-activated protein kinase) cascade in living cells, a result that may inform the analysis of knockout mice. Equally intriguing was the observation that mutant proteins with non-functional Ras-binding domains, and thereby deficient in Ras-mediated membrane recruitment, displayed only intermediate strength phenotypes. This confirms that secondary mechanisms exist to couple Ras to Raf in vivo. The strongest phenotype in the genetic screens was displayed by a S508N mutation that again did not correlate with a significant loss of kinase activity or membrane recruitment by oncogenic Ras in biochemical assays. Ser-508 lies within the Raf-1 activation loop, and mutation of this residue in Raf-1 and the equivalent Ser-615 in B-Raf revealed that this residue regulates Raf binding to MEK. Further characterization revealed that in response to activation by epidermal growth factor, the Raf-S508N mutant protein displayed both reduced catalytic activity and aberrant activation kinetics: characteristics that may explain the C. elegans phenotype.
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Caveolae and their proteins, the caveolins, transport macromolecules; compartmentalize signalling molecules; and are involved in various repair processes. There is little information regarding their role in the pathogenesis of significant renal syndromes such as acute renal failure (ARF). In this study, an in vivo rat model of 30 min bilateral renal ischaemia followed by reperfusion times from 4 h to 1 week was used to map the temporal and spatial association between caveolin-1 and tubular epithelial damage (desquamation, apoptosis, necrosis). An in vitro model of ischaemic ARF was also studied, where cultured renal tubular epithelial cells or arterial endothelial cells were subjected to injury initiators modelled on ischaemia-reperfusion (hypoxia, serum deprivation, free radical damage or hypoxia-hyperoxia). Expression of caveolin proteins was investigated using immunohistochemistry, immunoelectron microscopy, and immunoblots of whole cell, membrane or cytosol protein extracts. In vivo, healthy kidney had abundant caveolin-1 in vascular endothelial cells and also some expression in membrane surfaces of distal tubular epithelium. In the kidneys of ARF animals, punctate cytoplasmic localization of caveolin-1 was identified, with high intensity expression in injured proximal tubules that were losing basement membrane adhesion or were apoptotic, 24 h to 4 days after ischaemia-reperfusion. Western immunoblots indicated a marked increase in caveolin-1 expression in the cortex where some proximal tubular injury was located. In vitro, the main treatment-induced change in both cell types was translocation of caveolin-1 from the original plasma membrane site into membrane-associated sites in the cytoplasm. Overall, expression levels did not alter for whole cell extracts and the protein remained membrane-bound, as indicated by cell fractionation analyses. Caveolin-1 was also found to localize intensely within apoptotic cells. The results are indicative of a role for caveolin-1 in ARF-induced renal injury. Whether it functions for cell repair or death remains to be elucidated. Copyright (C) 2003 John Wiley Sons, Ltd.
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Undiluted culture filtrates of two commercial products of Trichoderma spp., Trichopel and Trichoflow, and two isolates of Penicillium citrinum completely inhibited the conidial germination of macroconidia of Claviceps africana , the cause of ergot or sugary disease of sorghum (Sorghum bicolor) in vitro . Similarly, Pseudomonas aeruginosa and Burkholderia cepacia completely inhibited macroconidial germination, with the former being more effective at high dilutions. In contrast, these bacterial isolates failed to inhibit infection in vivo in glasshouse tests with ergot-inoculated sorghum, but all fungal biocontrol agents (including an isolate of Epicoccum nigrum) reduced the severity of disease (percentage of infected spikelets per panicle), in some cases completely inhibiting the development of ergot. In a second glasshouse trial, optimum control was achieved when the biocontrol agents were applied 3-7 days before inoculation with conidia of C. africana .
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Epstein-Barr virus (EBV)-encoded oncogene latent membrane protein (LMP) 1, which is consistently expressed in multiple EBV-associated malignancies, has been proposed as a potential target antigen for any future vaccine designed to control these malignancies. However, the high degree of genetic variation in the LMP1 sequence has been considered a major impediment for its use as a potential immunotherapeutic target for the treatment of EBV-associated malignancies. In the present study, we have employed a highly efficient strategy, based on ex vivo functional assays, to conduct an extensive sequence-wide analysis of LMP1-specific T-cell responses in a large panel of healthy virus carriers of diverse ethnic origin and nasopharyngeal carcinoma patients. By comparing the frequencies of T cells specific for overlapping peptides spanning LMP1, we mapped a number of novel HLA class I- and class II-restricted LMP1 T-cell epitopes, including an epitope with dual HLA class I restriction. More importantly, extensive sequence analysis of LMP1 revealed that the majority of the T-cell epitopes were highly conserved in EBV isolates from Caucasian, Papua New Guinean, African, and Southeast Asian populations, while unique geographically constrained genetic variation was observed within one HLA A2 supertype-restricted epitope. These findings indicate that conserved LMP1 epitopes should be considered in designing epitope-based immunotherapeutic strategies against EBV-associated malignancies in different ethnic populations.
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Human cytomegalovirus (HCMV) can establish both nonproductive (latent) and productive (lytic) infections. Many of the proteins expressed during these phases of infection could be expected to be targets of the immune response; however, much of our understanding of the CD8(+)-T-cell response to HCMV is mainly based on the pp65 antigen. Very little is known about T-cell control over other antigens expressed during the different stages of virus infection; this imbalance in our understanding undermines the importance of these antigens in several aspects of HCMV disease pathogenesis. In the present study, an efficient and rapid strategy based on predictive bioinformatics and ex vivo functional T-cell assays was adopted to profile CD8(+)-T-cell responses to a large panel of HCMV antigens expressed during different phases of replication. These studies revealed that CD8(+)-T-cell responses to HCMV often contained multiple antigen-specific reactivities, which were not just constrained to the previously identified pp65 or IE-1 antigens. Unexpectedly, a number of viral proteins including structural, early/late antigens and HCMV-encoded immunomodulators (pp28, pp50, gH, gB, US2, US3, US6, and UL18) were also identified as potential targets for HCMV-specific CD8(+)-T-cell immunity. Based on this extensive analysis, numerous novel HCMV peptide epitopes and their HLA-restricting determinants recognized by these T cells have been defined. These observations contrast with previous findings that viral interference with the antigen-processing pathway during lytic infection would render immediate-early and early/late proteins less immunogenic. This work strongly suggests that successful HCMV-specific immune control in healthy virus carriers is dependent on a strong T-cell response towards a broad repertoire of antigens.
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Ageing results in a progressive, intrinsic and generalised imbalance of the control of regulatory systems. A key manifestation of this complex biological process includes the attenuation of the universal stress response. Here we provide the first global assessment of the ageing process as it affects the heat shock response, utilising human peripheral lymphocytes and cDNA microarray analysis. The genomic approach employed in our preliminary study was supplemented with a proteomic approach. In addition, the current study correlates the in vivo total antioxidant status with the age-related differential gene expression as well as the translational kinetics of heat shock proteins (hsps). Most of the genes encoding stress response proteins on the 4224 element microarray used in this study were significantly elevated after heat shock treatment of lymphocytes obtained from both young and old individuals albeit to a greater extent in the young. Cell signaling and signal transduction genes as well as some oxidoreductases showed varied response. Results from translational kinetics of induction of major hsps, from 0 to 24 It recovery period were broadly consistent with the differential expression of HSC 70 and HSP 40 genes. Total antioxidant levels in plasma from old individuals were found to be significantly lower by comparison with young, in agreement with the widely acknowledged role of oxidant homeostasis in the ageing process. (C) 2002 Elsevier Science Ireland Ltd. All rights reserved.
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The platelet inhibitory effects of the nitric oxide (NO) donor drug MAHMA NONOate ((Z-1-{N-methyl-N-[6-(N-methylammoniohexyl)amino] diazen-1-ium-1,2-diolate) were examined in anaesthetised rats and compared with those of S-nitrosoglutathione (GSNO; an S-nitrosothiol). Bolus administration of the aggregating agent ADP dose-dependently reduced the number of circulating free platelets. Intravenous infusions of MAHMA NONOate (3-30 nmol/kg/min) dose-dependently inhibited the effect of 0.3 mumol/kg ADP. MAHMA NONOate was approximately 10-fold more potent than GSNO. MAHMA NONOate (0.3-10 nmol/kg/min) also reduced systemic artery pressure and was again 10-fold more potent than GSNO. Thus MAHMA NONOate has both platelet inhibitory and vasodepressor effects in vivo. The dose ranges for these two effects overlapped, although blood pressure was affected at slightly lower doses. The platelet inhibitory effects compared favourably with those of GSNO, even though NONOates generate free radical NO which, in theory, could have been scavenged by haemoglobin. Therefore platelet inhibition may be a useful therapeutic property of NONOates. (C) 2003 Elsevier B.V. All rights reserved.
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The effects of S-nitrosocaptopril (SNOcap), administered either intravenously or by oral gavage, on pulmonary artery pressure (PAP) were examined in anaesthetised normotensive rats and rats with hypoxic pulmonary hypertension (10% oxygen for 1 week). Mean PAP (MPAP) values in hypoxic and normoxic rats were (mmHg) 26 +/- 1.7 and 15 +/- 1.1, respectively. When given intravenously, 1 mg kg(-1) SNOcap reduced MPAP by 28 and 32% in hypoxic and normoxic rats, respectively. The effects of 2 mg kg(-1) were no greater than those of 1 mg kg(-1). Pulmonary vasoclepressor responses reached equilibrium in 1.7 +/- 0.18 min following intravenous administration. When given orally 30 min before the measurement of PAP, 30 mg kg(-1), but not 10 mg kg(-1), significantly reduced MPAP in hypoxic rats to 17 +/- 1.5 mmHg. These in-vivo data are consistent with previous in-vitro data showing that SNOcap has direct pulmonary vasorelaxant properties in both large and small pulmonary arteries and also show that SNOcap causes pulmonary vasodepression in the setting of pulmonary hypertension. Since SNOcap also inhibits pulmonary vascular angiotensin converting enzyme (ACE) in pulmonary blood vessels (previous study), it would be an interesting drug with which to assess the benefits of direct pulmonary vasodilatation combined with ACE inhibition (which attentuates pulmonary vascular remodelling) in a long-term study in pulmonary hypertension.
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OBJECTIVE - To assess the effect of age on glucose metabolism by examining 1) glucose metabolism in young and middle-aged subjects when total or regional adiposity is taken into account and 2) in vitro glucose transport in adipose tissue explants from young and middle-aged women paired for total and abdominal adiposity. RESEARCH DESIGN AND METHODS - Study 1: body composition, subcutaneous abdominal and visceral adipose tissue areas, and fasting and oral glucose-stimulated glucose and insulin were measured in 84 young and 81 middle-aged men and in 110 young and 91 middle-aged women. Study 2: glucose uptake in subcutaneous abdominal and visceral adipose tissue explants were measured in eight young and eight middle-aged women. RESULTS - Study 1: young and middle-aged men showed similar subcutaneous abdominal tissue area, whereas fat mass and visceral adipose tissue were greater in middle-aged than in young men (P < 0.01). Fat mass and subcutaneous and visceral adipose tissue areas were greater in middle-aged as compared with young women (P < 0.01). Fasting plasma glucose and the glucose response to an oral glucose tolerance test were significantly higher in middle-aged than in young men and women (P < 0.001). Statistical control for visceral adipose tissue area eliminated the difference seen in glucose response in men and women. Study 2: glucose transport in subcutaneous and omental adipose tissue did not differ between young and middle-aged women. CONCLUSIONS - 1) Visceral obesity, more than age per se, correlates with glucose intolerance in middle-aged subjects; 2) aging does not influence in vitro adipose tissue glucose uptake.
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A regulatory protein, PpaA, involved in photosystem formation in the anoxygenic phototrophic proteobacterium Rhodobacter sphaeroides has been identified and characterized in vivo. Based on the phenotypes of cells expressing the ppaA gene in extra copy and on the phenotype of the ppaA null mutant, it was concluded that PpaA activates photopigment production and puc operon expression under aerobic conditions. This is in contrast to the function of the PpaA homologue from Rhodobacter capsulatus, AerR, which acts as a repressor under aerobic conditions [Dong, C., Elsen, S., Swem, L. R. & Bauer, C. E. (2002). J Bacteriol 184, 2805-2814]. The expression of the ppaA gene increases several-fold in response to a decrease in oxygen tension, suggesting that the PpaA protein is active under conditions of low or no oxygen. However, no discernible phenotype of a ppaA null mutant was observed under anaerobic conditions tested thus far. The photosystem gene repressor PpsR mediates repression of ppaA gene expression under aerobic conditions. Sequence analysis of PpaA homologues from several anoxygenic phototrophic bacteria revealed a putative corrinoid-binding domain. It is suggested that PpaA binds a corrinoid cofactor and the availability or structure of this cofactor affects PpaA activity.
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O setor portu??rio envolve uma grande diversidade de usu??rios e ??rg??os intervenientes, cada um com suas normas e processos pr??prios. Tal situa????o, associada ao fato de que todo o fluxo de informa????es e documentos solicitados pelos ??rg??os aos usu??rios era realizado em papel, n??o permitia clareza e efici??ncia na troca de informa????es. A falta de dados confi??veis e tempestivos tamb??m n??o permitia efetividade na gest??o e planejamento do setor. Nesse contexto, foi implantado, na fase inicial do Porto Sem Papel, um sistema que permitia a troca de informa????es e documentos digitais entre os usu??rios e os diversos ??rg??os intervenientes. Assim, os fluxos de informa????es e documentos, que antes eram realizados em papel, passaram a ser realizados digitalmente, dando agilidade e transpar??ncia aos processos. Cabe destacar que todas as informa????es est??o presentes agora em uma base ??nica de dados, o que permite a realiza????o de an??lises que subsidiem a gest??o e a melhoria de processos no setor portu??rio