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991.
de Moura SA de Sousa JM Lima DF Negreiros AN Silva Fde V da Costa LJ 《Gerodontology》2007,24(3):173-176
Objective: The aim of the present study was to analyse the characteristics of salivary production and its composition in individuals with burning mouth syndrome (BMS). Study Design: Salivary flow rate, concentrations of potassium, iron, chloride, thiocyanate, magnesium, calcium, phosphorus, glucose, total protein and urea, as well as the expression profile of salivary proteins were analysed by SDS‐PAGE. Results: The mean salivary flow rate among control patients was lower than that of BMS patients. Chloride, phosphorus and potassium levels were elevated in patients with BMS (p = 0.041, 0.001 and 0.034, respectively). Total salivary protein concentration was reduced in individuals with BMS (p = 0.223). Analysis of the expression of salivary proteins by Coomassie blue SDS‐PAGE revealed a lower expression of low molecular weight proteins in individuals with BMS compared to healthy controls. Conclusions: These results indicate that the identification and characterisation of low molecular weight salivary proteins in BMS may be important in understanding BMS pathogenesis, thus contributing to its diagnosis and treatment. 相似文献
992.
Pereira L Gonçalves J Franco-Duarte R Silva J Rocha T Arnold C Richards M Macaulay V 《Molecular biology and evolution》2007,24(3):868-874
The first complete mitochondrial DNA (mtDNA) sequences (approximately 16,569 bp) in 20 patients with asthenozoospermia and a comparison with 23 new complete mtDNA sequences in teratoasthenozoospermic individuals, confirmed no sharing of specific polymorphisms or specific mitochondrial lineages between these individuals. This is strong evidence against the accepted claim of a major role played by mtDNA in male fertility, once supported by haplogroup association studies based on the screening of hypervariable region I. The hypothesis of maternally driven selection acting in male reproductive success must thus be treated with caution. 相似文献
993.
Pedrazzoli M Louzada FM Pereira DS Benedito-Silva AA Lopez AR Martynhak BJ Korczak AL Koike Bdel V Barbosa AA D'Almeida V Tufik S 《Chronobiology international》2007,24(1):1-8
A Clock polymorphism T to C situated in the 3' untranslated region (3'-UTR) has been associated with human diurnal preference. At first, Clock 3111C had been reported as a marker for evening preference. However these data are controversial, and data both corroborating and denying them have been reported. This study hypothesizes that differences in Clock genotypes could be observed if extreme morning-type subjects were compared with extreme evening-type subjects, and the T3111C and T257G polymorphisms were studied. The possible relationship between both polymorphisms and delayed sleep phase syndrome (DSPS) was also investigated. An interesting and almost complete linkage disequilibrium between the polymorphisms T257G in the 5' UTR region and the T3111C in the 3' UTR region of the Clock gene is described. Almost always, a G in position 257 corresponds to a C in position 3111, and a T in position 257 corresponds to a T in position 3111. The possibility of an interaction of these two regions in the Clock messenger RNA structure that could affect gene expression was analyzed using computer software. The analyses did not reveal an interaction between those two regions, and it is unlikely that this full allele correspondence affects Clock gene expression. These results show that there is no association between either polymorphism T3111C or T257G in the Clock gene with diurnal preference or delayed sleep phase syndrome (DSPS). These controversial data could result from the possible effects of latitude and clock genes interaction on circadian phenotypes. 相似文献
994.
Molecular modelling and synthetic arguments are valuable tools for the design of potential immunosuppressant agents. In this paper, eight proline-based compounds related to the AP1867 structure are studied and at least one of them is found to be a structurally good candidate for the inhibition of FKBP protein. Theoretical calculations were carried out to locate the most energetically favorable chemical substituent group relative to a core skeleton group on interaction with the FKBP binding cavity. Connolly accessible surface calculations have complemented the molecular mechanics and dynamics approaches. Calculated results were also analyzed on the basis of hydrogen bond interactions, relative energies of interaction, root-mean square deviations of amino acid residues of the crystallized protein, and orientation of the substituent groups within the active site. The results show a significant reduction in the relative interaction energies and very good shape complementarities between our final analog compound and the FKBP binding pocket. 相似文献
995.
Gedoz L Lauxen Ida S Sant'Ana MF Rados PV 《Analytical and quantitative cytology and histology / the International Academy of Cytology [and] American Society of Cytology》2007,29(4):231-238
OBJECTIVE: To evaluate cell proliferation in clinically healthy oral mucosa exposed to smoking and alcohol carcinogens over a period of 24 months using the AgNOR staining technique. STUDY DESIGN: Sixty patients were initially evaluated: 17 were control individuals, 25 were smokers and 18 were smokers and alcohol drinkers. Fifty-two of these patients were reevaluated. Specimens for cytology were obtained from swabs of lower lip mucosa, border of the tongue and floor of the mouth and underwent AgNOR staining for evaluation of mean number and mean area of AgNOR dots per nucleus and percentage of nuclei with > 3 and > 5 AgNOR dots. Student t and Kruskal-Wallis tests were used to compare values obtained. RESULTS: A statistically significant increase was found in mean number of AgNOR dots per nucleus in 2 groups. One group showed a tendency toward increase of these values. The results of the longitudinal evaluation (Kruskal-Wallis test) revealed a statistically significant difference in number and area of AgNOR dots in the cells of the lower lip. CONCLUSION: The increase of the variables suggests that the longitudinal evaluation of changes in cell proliferation in individuals exposed to smoking and alcohol carcinogens may be a useful monitoring tool. 相似文献
996.
997.
Using microdialysis, we have monitored extracellular levels of amino acids and related amines in the human liver at three stages of the transplantation procedure: donor retrieval, back table preparation and during 48 h post-implantation. By comparing the ratio of mean levels at the donor and back table stages, with the ratio between early (2-6 h) and late (43-48 h) post-reperfusion, these amines were classified into one of three groups. In one group, back table levels were markedly higher than during the donor stage, with levels declining over time post-reperfusion. A second group had much lower levels in the back table than during the donor phase, and post-reperfusion levels were either stable or increased over time. Concentrations of amino acids in the final group remained relatively constant at all stages. This study illustrates the value of microdialysis in providing organ-specific metabolic data that may indicate specific mechanisms of poor graft function. 相似文献
998.
Scalon Cunha LC Andrade e Silva ML Cardoso Furtado NA Vinhólis AH Gomes Martins CH da Silva Filho AA Cunha WR 《Zeitschrift für Naturforschung. C, Journal of biosciences》2007,62(9-10):668-672
Triterpene acids (ursolic, oleanoic, gypsogenic, and sumaresinolic acids) isolated from Miconia species, along with a mixture of ursolic and oleanolic acids and a mixture of maslinic and 2-a-hydroxyursolic acids, as well as ursolic acid derivatives were evaluated against the following microorganisms: Streptococcus mutans, Streptococcus mitis, Streptococcus sanguinis, Streptococcus salivarius, Streptococcus sobrinus, and Enterococcus faecalis, which are potentially responsible for the formation of dental caries in humans. The microdilution method was used for the determination of the minimum inhibitory concentration (MIC) during the evaluation of the antibacterial activity. All the isolated compounds, mixtures, and semi-synthetic derivatives displayed activity against all the tested bacteria, showing that they are promising antiplaque and anticaries agents. Ursolic and oleanolic acids displayed the most intense antibacterial effect, with MIC values ranging from 30 microg/mL to 80 microg/mL. The MIC values of ursolic acid derivatives, as well as those obtained for the mixture of ursolic and oleanolic acids showed that these compounds do not have higher antibacterial activity when compared with the activity observed with either ursolic acid or oleanolic acid alone. With regard to the structure-activity relationship of triterpene acids and derivatives, it is suggested that both hydroxy and carboxy groups present in the triterpenes are important for their antibacterial activity against oral pathogens. 相似文献
999.
I.R. Siqueira C. Fochesatto I.L.S. Torres A.L. da Silva D.S. Nunes E. Elisabetsky C.A. Netto 《Phytomedicine》2007,14(11):763-769
Ptychopetalum olacoides (PO) roots are used by Amazonian peoples to prepare traditional remedies for treating various central nervous system conditions in which free radicals are likely to be implicated. Following the identification of PO ethanol extract (POEE) free-radical scavenging properties in vitro, the aim of this study was to verify the in vivo antioxidant effect of POEE. Aging mice (14 months) were treated (i.p.) with saline, DMSO (20%) or POEE (100mg/kg body wt.), and the hippocampi, cerebral cortex, striata, hypothalamus and cerebellum dissected out 60 min later to measure antioxidant enzyme activities, free-radical production and damage to macromolecules. POEE administration reduced free-radical production in the hypothalamus, lead to significant decrease in lipid peroxidation in the cerebral cortex, striatum and hypothalamus, as well as in the carbonyl content in cerebellum and striatum. In terms of antioxidant enzymes, catalase activity was increased in the cortex, striatum, cerebellum and hippocampus, while glutathione peroxidase activity was increased in the hippocampus. This study suggests that POEE contains compounds able to improve the cellular antioxidant network efficacy in the brain, ultimately reducing the damage caused by oxidative stress. 相似文献
1000.
do Vale A Costa-Ramos C Silva A Silva DS Gärtner F dos Santos NM Silva MT 《Cellular microbiology》2007,9(4):988-1003
Bacterial modulation of phagocyte cell death is an emerging theme in pathogenesis. Here we describe the systemic destruction of macrophages and neutrophils by the Gram-negative Photobacterium damselae ssp. piscicida (Phdp) in fish pasteurellosis, a deadly systemic infection. Following experimental inoculation, Phdp spreads by bacteraemia and colonizes the organs, producing a septicaemic infection, and secretes the apoptogenic exotoxin AIP56 which is systemically disseminated. In experimental and natural pasteurellosis, destruction of macrophages and neutrophils by secondary necrosis following caspase-3-associated apoptosis was seen predominantly in the spleen, head kidney and gut lamina propria. Identical phagocyte destruction occurred after injection of rAIP56, but not of heat-inactivated rAIP56, or AIP56-negative Phdp strains, indicating that AIP56 is responsible for phagocyte destruction occurring in pasteurellosis. Active caspase-3 and active neutrophil elastase are present in the blood in advanced infection, indicating that phagocyte lysis by secondary necrosis is accompanied by release of tissue-damaging molecules. The AIP56-induced lysis of phagocytes represents a very efficient, self-amplifying etiopathogenic mechanism, because it results in two effects that operate in concert against the host, namely, evasion of the pathogen from a crucial defence mechanism through the destruction of both professional phagocytes, and release of tissue-damaging molecules. The induction by a bacterial exotoxin of in vivo systemic lysis of both professional phagocytes by secondary necrosis, now described for the first time, may represent an overlooked etiopathogenic mechanism operating in other infections of vertebrates. 相似文献