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Fourteen male patients with periodontitis and 10 patients free of periodontitis were included in the study. The concentrations of testosterone (T), calcium (Ca), magnesium (Mg), and zinc (Zn) were measured in serum and parotid saliva. Patients with periodontitis had increased Ca and decreased Zn serum levels, and they had decreased Ca and increased T levels in parotid saliva. Furthermore, there was a low correlation between parotid saliva T and Mg levels in the patients with periodontitis (r = 0.61, n = 14, t = 2.663, p less than 0.005), and there is an inverse relationship between serum and parotid saliva Mg levels (r = - 0.58, n = 14, t = 2.468, p less than 0.05).  相似文献   

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1. The role of the sympathetic autonomic division on the parotid gland of normal and thyroparathyroidectomized (t.x.p.t.x.) goats was studied. 2. The salivary flow rate and concentration of Ca, P and protein was tested during the intravenous infusions of sympathomimetic and sympatholytic agents. 3. The intravenous infusion of isoprenaline modified the salivary flow rate and the concentration of total protein. 4. None of the tested drugs modified significantly the concentration of Ca and P in the parotid saliva. 5. The results obtained in normal and t.x.p.t.x animals were similar; it seems that PTH is not involved in the observed changes.  相似文献   

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Effects of radiotherapy on human parotid saliva   总被引:3,自引:0,他引:3  
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Recent findings indicate that ion-chelator probes with tetracarboxylate structure bind proteins. It was suggested that these fluorescent probes are valuable tools to gain information on protein structure through the energy transfer from tryptophans to the bound probe. Here, the binding of the fluorescent probe Mag-Indo-1 to bovine serum albumin (BSA) was investigated. Mag-Indo-1 was reported previously to serve as a probe for magnesium cations (Kd = 2.8 x 10(-4) M for zero ionic strength) which can also interact with calcium cations (Kd = 7.5 x 10(-7) M). Probe complexation with protein results in a shift of the emission fluorescence spectrum of the probe from 480 to 457 nm. We used emission fluorescence techniques to monitor this interaction. Computational resolution of the complex fluorescence spectra and a new software to test the theoretical model were developed in our laboratory. This enabled us to calculate the number of interacting sites and the dissociation constants. The fluorescent probe Mag-Indo-1 binds at a singular site with high affinity (Kd = 1.8 x 10(-7) M) to bovine serum albumin (BSA). Since proteins are known to bind several compounds unspecifically, we have studied the influence of EDTA as a competitor of the probe. Our findings suggest that the BSA binding site is identical for both Mag-Indo-1 and EDTA. We found that EDTA binds the protein with Kd = 0.4 x 10(-3) M. We studied the influence of calcium and found that Mag-Indo-1 does not bind the calcium free Apo-protein anymore.  相似文献   

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Effect of magnesium, calcium and EDTA on slime production by 15 slime-positive and 13 slime-negative Staphylococcus epidermidis strains isolated from various clinical specimens was determined. The slime production on tryptic soy broth was significantly enhanced after addition of 128 mumol/L Mg2+. Similarly, the addition of Ca2+ caused a significant increase in slime production of all tested strains when concentration of Ca2+ exceeded 64 mumol/L. In contrast, in the presence of EDTA the slime production by all strains was significantly reduced. Hence Ca2+ and Mg2+ increase slime production of S. epidermidis. This finding is important in the context of the pathogenesis of biomedical implant infections caused by S. epidermidis.  相似文献   

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The major proteins in human parotid saliva, isolated in Fractions II-V following chromatography on Sephacryl S-200, DEAE-Sephadex A-50, or CM cellulose, contain 6 moles of phosphate per mole of protein, the phosphate probably bound to the protein via an ester linkage. This phosphate represents greater than 90% of the protein-bound phosphate in human parotid saliva. Neither purified gustin nor amylase, the two other major proteins in human parotid saliva, contain phosphate.  相似文献   

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A three factorial designed feeding experiment with common carp (Cyprinus carpio L.) was carried out in an intensive experimental rearing system. Fish (initial body weight 200 g) were fed on two different levels of dietary energy (16 and 18 MJ DE/kg DM), two different levels of protein (320 and 420 g CP/kg DM) and also two different feeding intensities (100% and 75% of the maximum intake). The experiment was terminated when fish reached a mean body weight of 1300 g.

Growth, feed utilization and nutrient composition of the whole body and fillet were observed. The highest growth was obtained when the fish were fed on the diet containing high dietary energy and high dietary protein with satiation feeding. High dietary energy, high dietary protein and restriction of feed intake improved feed conversion ratios. High dietary energy, low dietary protein and restrictive feeding increased energy utilization. Low dietary protein and restrictive feeding resulted in better protein utilization.

Fish fed with high dietary energy contained more fat and less protein in their carcasses. A lower fat content but higher protein and higher ash content in fish carcasses was shown when fish were fed with a diet high in protein and fed restrictively.  相似文献   

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Small quantities of parotid saliva were obtained from 7 of 11 rats in which hypokalemia was induced by treatment with deoxycorticosterone acetate (DOCA). Thirst in the treated rats was indicated by an increase in water consumption. A decrease of 28% in plasma potassium levels indicated that the DOCA-treated rats had become hypokalemic; chloride decreased 6-7% while sodium was unchanged. Saliva showed significant increases in potassium and protein and a decrease in sodium; lactate dehydrogenase-2 and -4 bands appeared darker on the electrophoretic profile. These changes are relevant to the clinical manifestations and diagnosis of hypokalemia.  相似文献   

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The effects of increasing concentrations of magnesium (Mg2+), calcium (Ca2+) or EDTA, and pH on the adhesion of five slime-positive strains of Staphylococcus epidermidis (Se+) to plastic were examined using an in vitro microwell assay. The addition of Mg2+ (as either MgSO4 or MgCl2) to the bacterial suspension in concentrations as low as 16 microM significantly enhanced the adhesion of all test strains to plastic (P < 0.001). Similarly, the addition of Ca2+ (as CaCl2) in concentrations exceeding 128 microM produced a significant increase in the adhesion of all test strains, but not to the extent observed with Mg2+. In contrast, the adhesion of all test strains to plastic was significantly reduced in the presence of EDTA at concentrations greater than 8 mM. However, EDTA in concentrations as low as 0.25 mM caused a significant decrease in the adhesion of two strains of Se+. The effect of pH was variable, but at a pH of 5.0 and 6.0, the adhesion of all test strains was significantly reduced compared to control values at a pH of 7.0. Two strains showed a significant increase in adhesion at a pH of 8.0. We also compared the effects of these variables on the adherence of a slime-negative phase variant derived from a slime-positive parent strain. With the exception of pH, the adhesion of both strains in response to increasing divalent cations or EDTA was similar. These data indicate that, in addition to hydrophobic interactions, ligand-specific binding, and slime production, pH and divalent cations, especially Mg2+, are important determinants of the adhesion of S. epidermidis to plastic surfaces in vitro.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

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The purpose of this study was to investigate the effects of isoflurane on unstimulated and pilocarpine-stimulated parotid saliva secretion. Ten male Sprague-Dawley rats weighing 350-400 g were randomized into two groups, and the saliva flow rate and lag phase were measured at two doses of isoflurane in a crossover study design. Increasing the isoflurane concentration from 1% to 2% was associated with a 19% decrease in saliva secretion rate, and the lag to saliva secretion was increased by 155%. To clarify whether the effect of isoflurane (1.5%) on the parotid flow varied with stimulus intensity, we measured the parotid flow induced by seven different doses of pilocarpine on sham-irradiated rats and rats irradiated with single doses of 15 Gy. A maximal pilocarpine response was obtained with 1.5 mg/kg in both irradiated and sham-irradiated rats; however, the parotid flow of the irradiated rats was 50% slower than that of the sham-irradiated rats. In conclusion, 1.5% isoflurane was found to be a good compromise between proper anesthesia and isoflurane-induced inhibition of saliva secretion. Pilocarpine induces saliva secretion in a dose-dependent matter, with supra-maximal stimulation achieved using 1.5 mg/kg.  相似文献   

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Human salivary secretions contain many proteins in which proline forms an unusually large fraction of the amino-acid residues present, typically from 20% to over 40%. These proteins are also unusually rich in glycine and glutamine, generally account for over half the total protein in saliva, and include acidic, basic and glycosylated molecules. The functions of most of these are not clearly defined. One group, however, the acidic proline-rich phosphoproteins (PRP), have been shown to be potent inhibitors of secondary precipitation (crystal growth) of calcium phosphate salts. Acting together with a salivary protein inhibitor of primary precipitation of calcium phosphates, statherin, the PRP stabilize saliva which is supersaturated with respect to the calcium phosphate salts which form dental enamel. These inhibitory activities act to provide a protective, reparative, but stable environment for dental enamel, which is important for maintaining the health of the teeth. The PRP are a complex group of phosphoproteins which include four major and at least eight minor members. The primary structures of three of the major proteins have been determined. These are PRP-1, also designated Protein-C, PRP-3, also designated Protein-A (17), and PRP-4. The designations PRP-1,-2,-3 and -4 will be used here. The purpose of this paper is to report the complete primary structure of PRP-2 as a further step towards establishing the structural basis of the biological activity of the PRP, and clarifying the genetic and biosynthetic relationships of these closely related proteins.  相似文献   

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