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81.
82.
Walter L. Siqueira Young Ho Lee Yizhi Xiao Katharina Held Williston Wong 《Proteomics》2012,12(22):3426-3435
With recent progress in the analysis of the salivary proteome, the number of salivary proteins identified has increased dramatically. However, the physiological functions of many of the newly discovered proteins remain unclear. Closely related to the study of a protein's function is the identification of its interaction partners. We investigated interactions among and functions of histatin 1 and the other proteins that are present in saliva by using high‐throughput mass spectrometric techniques. This led to the identification of 43 proteins able to interact with histatin 1. In addition, we found that these protein–protein interactions protect complex partners from proteolysis and modulate their antifungal activity. Our data contribute significantly to characterization of the salivary interactome and to understanding the biology of salivary protein complexes. 相似文献
83.
Influence of nutrient management on growth and nutrient use efficiency of two plant species for mineland revegetation 下载免费PDF全文
João M. Carvalho Silvio J. Ramos Antonio E. Furtini Neto Markus Gastauer Cecilio F. Caldeira Jr. José O. Siqueira Maria L. S. Silva 《Restoration Ecology》2018,26(2):303-310
Rehabilitation of degraded areas by mining activities is necessary to achieve sustainable mining. For an effective revegetation, the understanding of plant growth and the nutrient requirements of native plant species, especially those with the potential to be used in the rehabilitation of mined areas such as waste piles or mine pits, is indispensable. In this study, we evaluated the growth performance, nutrient levels, and nutrient use efficiency of an endemic plant (Mimosa acutistipula var. ferrea) and ruderal shrub (Solanum crinitum) that are both found in ferriferous savannas, locally called “canga” in Carajás Mineral Province, Brazil. An experiment was conducted under greenhouse conditions using samples of three different soils (oxisol, canga soil, and iron mining waste) without and with nutrient application; additionally, an omission trial was carried out in canga soils. Fertilization increased the growth of both plant species in all substrates. Macronutrient omission reduced the growth of plants stronger than micronutrient omission, indicating that the lack of N, P, and K may especially impact the rehabilitation of areas. The growth of S. crinitum was higher than M. acutistipula var. ferrea, highlighting its preponderance in mineland rehabilitation, although concerns regarding its role as a ruderal species persist. Therefore, further research is necessary for a risk assessment of the propagation of S. crinitum within mineland restoration projects. 相似文献
84.
Siqueira IR Elsner VR Leite MC Vanzella C Moysés Fdos S Spindler C Godinho G Battú C Wofchuk S Souza DO Gonçalves CA Netto CA 《Neurochemistry international》2011,58(4):527-532
Ascorbate, an intracellular antioxidant, has been considered critical for neuronal protection against oxidant stress, which is supported especially by in vitro studies. Besides, it has been demonstrated an age-related decrease in brain ascorbate levels. The aims of the present study were to investigate ascorbate uptake in hippocampal slices from old Wistar rats, as well as its neuroprotective effects in in vitro and in vivo assays. Hippocampal slices from male Wistar rats aged 4, 11 and 24 months were incubated with radiolabeled ascorbate and incorporated radioactivity was measured. Hippocampal slices from rats were incubated with different concentrations of ascorbate and submitted to H(2)O(2)-induced injury, cellular damage and S100B protein levels were evaluated. The effect of chronic administration of ascorbate on cellular oxidative state and astrocyte biochemical parameters in the hippocampus from 18-months-old Wistar rats was also studied. The ascorbate uptake was decreased in hippocampal slices from old-aged rats, while supplementation with ascorbate (2 weeks) did not modify any tested oxidative status in the hippocampus and the incubation was unable to protect hippocampal slices submitted to oxidative damage (H(2)O(2)) from old rats. Our data suggest that the decline of ascorbate uptake might be involved in the brain greater susceptibility to oxidative damage with advancing age and both in vitro and vivo assays suggest that ascorbate supplementation did not protect hippocampal cells. 相似文献
85.
Germano Siqueira Adriane MF Milagres Walter Carvalho Gerald Koch André Ferraz 《Biotechnology for biofuels》2011,4(1):7
Background
Lignin and hemicelluloses are the major components limiting enzyme infiltration into cell walls. Determination of the topochemical distribution of lignin and aromatics in sugar cane might provide important data on the recalcitrance of specific cells. We used cellular ultraviolet (UV) microspectrophotometry (UMSP) to topochemically detect lignin and hydroxycinnamic acids in individual fiber, vessel and parenchyma cell walls of untreated and chlorite-treated sugar cane. Internodes, presenting typical vascular bundles and sucrose-storing parenchyma cells, were divided into rind and pith fractions. 相似文献86.
Santos Lda S Fernandes VC Cruz SG Siqueira WC Goes AM Pedroso ER 《Memórias do Instituto Oswaldo Cruz》2012,107(1):1-10
The levels of total of IgG, IgG1, IgG2, IgG3 and IgG4 were evaluated in 54 patients with chronic paracoccidioidomycosis (PCM) before, during and after treatment using an enzyme-linked immunosorbent assay with Mexo and recombinant Pb27 (rPb27) as the antigens. Mexo was effective in distinguishing PCM patients from individuals in the negative control group (NC) based on total IgG and rPb27 performed worse than Mexo when these two groups were compared. IgG1, IgG2, IgG3 and IgG4 could not be used to clearly distinguish PCM patients from those in the NC group using either antigen. There was no clear relationship between antibody levels and the period of treatment. The majority of patients presented with decreased antibody levels during treatment, with no statistically significant differences among the different periods of treatment. Only IgG4 presented a negative correlation between its levels and clinical improvement during treatment. In total, 65% of untreated PCM patients showed reactivity against IgG4 when the Mexo antigen was used and this reactivity decreased over the course of treatment. There was a tendency towards decreasing antibody levels during treatment, but these antibody levels did not necessarily clear after the treatment was stopped. Mexo was useful for PCM diagnosis using total IgG; however, more studies are necessary before this antigen can be used in measuring the levels of total IgG and its subclasses for monitoring patients during treatment. 相似文献
87.
Mingoti GZ Castro VS Méo SC Sá Barretto LS Garcia JM 《In vitro cellular & developmental biology. Animal》2011,47(5-6):361-367
Aiming to standardize in vitro production of bovine embryos and to obtain supplements to replace serum in culture media, this study evaluated the nuclear maturation kinetics and embryonic development in bovine after in vitro maturation (IVM) and culture (IVC) with several macromolecules (animal origin: bovine serum albumin (BSA), fetal calf serum (FCS); synthetic: polyvinyl alcohol (PVA), polyvinyl pyrrolidone (PVP), Ficoll, and Knockout) at two oxygen tensions (20% and 5% O(2)). Regarding nuclear kinetics, neither the presence of the expected stage (metaphase I, transition anaphase to telophase, and metaphase II) at each evaluation moment (6, 18, and 24?h after IVM, respectively) nor the accelerated polar body emission (at 18?h after IVM) related developmental competence to blastocyst stage when different supplements were compared. Independently of supplement, cleavage rates at 20% O(2) (61.6-79.2%) were higher than at 5% O(2) (38.9-58.7%). At 20% O(2), higher blastocyst and hatching rates, respectively, were obtained in treatments BSA, FCS, Knockout, and control group (IVM with FCS and IVC with BSA + FCS, 14.0-23.5% and 6.8-15.4%) in comparison to PVA, PVP, and Ficoll (0%). The same was observed at 5% O(2) for blastocyst rates with BSA, FCS, Knockout, and control (5.4-16.8%) and for hatching rates with BSA, FCS, and control (2.0-11.1%). We can conclude that producing bovine embryos at 20% O(2) during the entire IVP process resulted in higher developmental rates than at 5% O(2). In addition, while defined macromolecules PVA, PVP, and Ficoll were not suitable for embryonic development, the synthetic serum Knockout was able to replace serum and albumin for IVP in bovine at 20% O(2). 相似文献
88.
Sleep disorders and demand for medical services: evidence from a population-based longitudinal study
Background
The aim of this study was to investigate whether insomnia and obstructive sleep apnea (OSA) were predictors of hospitalizations or emergency department visits during two years following the Sao Paulo Epidemiologic Sleep Study (EPISONO) sample.Methods and Findings
All participants (n = 1,101) who underwent a baseline evaluation between July and December 2007 were contacted in December 2009 and asked to fill out a questionnaire about body weight changes, number of hospitalizations and visits to the emergency department. Participants lost during the follow-up period represented 3.2% (n = 35) and 7 subjects had died. Hospitalizations were reported by 116 volunteers (10.5%) and emergency department visits were reported by 136 participants (12.4%). The average body mass index (BMI) did not vary significantly between the first and the second assessment [26.7(95%CI:26.3–27.1) vs. 26.9(26.5–27.4) kg/m2]. After adjusting for confounders, a multiple logistic regression model revealed that female gender [1.4(1.0–1.9)], age ≥40 years, insomnia diagnosed according to the DSM-IV criteria [1.6(1.0–2.6)], and apnea-hypopnea index ≥15 [1.5(1.0–2.2)] were predictors of hospitalizations and/or demand for emergency services.Conclusion
Our study of a probabilistic sample of the Sao Paulo inhabitants shows that over a period of two years, insomnia and OSA were both associated with health impairment. Considering the high prevalence and public health burden of sleep disorders, the consequences of untreated disease for both the individual and society are undeniable and should be addressed. 相似文献89.
Soares RP Barbosa SE Dujardin JP Schofield CJ Siqueira AM Diotaiuti L 《Memórias do Instituto Oswaldo Cruz》1999,94(2):161-166
Among the triatomines considered as secondary in the epidemiology of Chagas disease, Rhodnius neglectus is frequently captured in artificial ecotopes, especially peridomiciliary ones, rarely producing colonies indoors. Nevertheless, the presence of breeding colonies in houses was unquestionably demonstrated in some areas of the State of Goiás, Brazil. Previous isoenzyme comparisons of this species with morphologically close triatomines, such as R. prolixus, R. robustus or R. nasutus, did not produce definitive conclusions because of doubt about the geographical origin of the R. neglectus. We present here, for the first time, the isoenzyme profile of topotypes of R. neglectus. In addition, wild caught specimens from the type locality, Uberaba (Minas Gerais, Brazil), were compared to wild caught specimens from Jaraguá (Goiás, Brazil), where R. neglectus is more frequently reported invading houses. We used isoenzyme, morphology and morphometry analysis. Neither morphological nor enzymatic differences were found between areas, but metric, size-related divergence was evidenced between them. 相似文献
90.
Patricia C lia da Rocha Viana Maria Clara Caldas Bussiere Rachel Siqueira de Queiroz Sim es Marins Luiz Silveira Menna-Barreto Leopoldo Jos Cury 《Biological Rhythm Research》2003,34(4):347-354
The purposes of this study were to observe the presence of diurnal rhythms in plasma ions and metabolites levels in Thoroughbred racehorses under physical training, and to determine the time of blood sampling in clinical investigations. Plasma calcium, phosphorus, potassium, sodium, chloride, magnesium, iron, glucose, cholesterol, triglycerides, and total proteins levels were studied over a 72-h period. Blood samples were taken every 4 hours from five male and five female Thoroughbred racehorses under physical training. COSINOR analyses (P = 0.05) were done. Plasma potassium and triglycerides showed significant diurnal rhythms, with its acrophases occurring at dark period. No significant diurnal rhythms of other variables were found. It was concluded that, in Thoroughbred racehorses, the optimum time for potassium, and triglycerides sampling seems to be light period. And for other variables, time of diagnosis is not important. 相似文献