Trace elements and electrolytes in human resting mixed saliva after exercise.
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OBJECTIVES: Exercise is known to cause changes in the concentration of salivary components such as amylase, Na, and Cl. The aim of this investigation was to evaluate the effect of physical exercise on the levels of trace elements and electrolytes in whole (mixed) saliva. METHODS: Forty subjects performed a maximal exercise test on a cycle ergometer. Samples of saliva were obtained before and immediately after the exercise test. Sample concentrations of Fe, Mg, Sc, Cr, Mn, Co, Cu, Zn, Se, Sr, Ag, Sb, Cs, and Hg were determined by inductively coupled plasma mass spectrometry and concentrations of Ca and Na by atomic absorption spectrometry. RESULTS: After exercise, Mg and Na levels showed a significant increase (p < 0.05) while Mn levels fell (p < 0.05). Zn/Cu molar ratios were unaffected by exercise. CONCLUSIONS: Intense physical exercise induced changes in the concentrations of only three (Na, Mg, and Mn) of the 16 elements analysed in the saliva samples. Further research is needed to assess the clinical implications of these findings. (+info)
The use of infrared spectrophotometry for measuring body water spaces.
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BACKGROUND: The conventional method of measuring total body water by the deuterium isotope dilution method uses gas isotope ratio mass spectrometry (IRMS), which is both expensive and time-consuming. We investigated an alternative method, using Fourier transform infrared spectrophotometry (FTIR), which uses less expensive instrumentation and requires little sample preparation. METHOD: Total body water measurements in human subjects were made by obtaining plasma, saliva, and urine samples before and after oral dosing with 1.5 mol of deuterium oxide. The enrichments of the body fluids were determined from the FTIR spectra in the range 1800-2800 cm-1, using a novel algorithm for estimation of instrumental response, and by IRMS for comparison. RESULTS: The CV (n = 5) for repeat determinations of deuterium oxide in biological fluids and calibrator solutions (400-1000 micromol/mol) was found to be in the range 0.1-0.9%. The use of the novel algorithm instead of the integration routines supplied with the instrument gave at least a threefold increase in precision, and there was no significant difference between the results obtained with FTIR and those obtained with IRMS. CONCLUSION: This improved infrared method for measuring deuterium enrichment in plasma and saliva requires no sample preparation, is rapid, and has potential value to the clinician. (+info)
A simple saliva-based test for detecting antibodies to human immunodeficiency virus.
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This study was performed to determine the feasibility of using saliva as a diagnostic medium for the detection of antibodies to human immunodeficiency virus type 1 (HIV-1) and HIV-2 under nonlaboratory conditions and to evaluate the performance characteristics of such a test. We developed for this purpose a self-contained kit (Saliva. Strip [ST]), which combines the collection and processing, as well as the analysis, of the specimen. The kit's performance was evaluated in a blinded study. Saliva collection was facilitated with a specially designed device that contains a sample adequacy indicator, and immunochromatography test strips were used for the analysis. A total of 1,336 matched serum and saliva specimens (684 reactive and 652 nonreactive specimens) were tested. We tested sera using an enzyme immunoassay (EIA) and a rapid strip test. Sera reactive in one of the assays were also analyzed by Western blotting. Sensitivity and specificity were 99.4 and 99.4%, respectively, for ST, 100 and 99.1%, respectively, for EIA, and 99.7 and 100%, respectively, for the serum strip test. The saliva test performed well when HIV-2-positive sera or a low-titer performance panel (HIV-1) of serum or plasma specimens were diluted (1:2,000) in nonreactive saliva. Because the methodology we present here uses a noninvasively obtained medium, the methodology may be suitable for use in the field where laboratory support and personnel are limited, such as community outreach programs, doctors' offices, surveillance studies, and community hospitals. (+info)
Defective secretion of saliva in transgenic mice lacking aquaporin-5 water channels.
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Aquaporin-5 (AQP5) is a water-selective transporting protein expressed in epithelial cells of serous acini in salivary gland. We generated AQP5 null mice by targeted gene disruption. The genotype distribution from intercross of founder AQP5 heterozygous mice was 70:69:29 wild-type:heterozygote:knockout, indicating impaired prenatal survival of the null mice. The knockout mice had grossly normal appearance, but grew approximately 20% slower than litter-matched wild-type mice when placed on solid food after weaning. Pilocarpine-stimulated saliva production was reduced by more than 60% in AQP5 knockout mice. Compared with the saliva from wild-type mice, the saliva from knockout mice was hypertonic (420 mosM) and dramatically more viscous. Amylase and protein secretion, functions of salivary mucous cells, were not affected by AQP5 deletion. Water channels AQP1 and AQP4 have also been localized to salivary gland; however, pilocarpine stimulation studies showed no defect in the volume or composition of saliva in AQP1 and AQP4 knockout mice. These results implicate a key role for AQP5 in saliva fluid secretion and provide direct evidence that high epithelial cell membrane water permeability is required for active, near-isosmolar fluid transport. (+info)
Dexamethasone in resting and exercising men. II. Effects on adrenocortical hormones.
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This study presents the reactions of adrenocorticosteroids (cortisol and aldosterone) and sex steroids [testosterone, androstenedione, and dehydroepiandrosterone and its sulfate (DHAS)] 1) to a dexamethasone (Dex) treatment, which is expected to lower steroid levels via the ACTH blockade, and 2) to an exercise bout at maximal O(2) consumption, which is expected to increase steroid production via ACTH stimulation. Consistent with the decrease in ACTH, all steroids except testosterone reacted negatively to Dex, independently of the dose (0.5 and 1.5 mg administered twice daily for 4.5 days). After exercise, plasma ACTH rose to 600% of basal value, resulting in a significant increase in aldosterone and adrenal androgens, but cortisol and DHAS were unaffected. This apparently surprising result can be explained by differences in peripheral metabolism: a theoretical calculation predicted that after 15 min the increase in hormone concentration may only reach 12% for cortisol and 2% for DHAS. For cortisol and adrenal androgens, assays were carried out using plasma and saliva. The consistent results obtained from the two matrices allow us to consider salivary assays as a useful tool for steroid abuse detection. (+info)
The effect of potassium chloride infusion of parotid salivary flow and composition in conscious sheep.
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The composition and flow of parotid saliva in conscious sheep was measured before, during and after the intravenous infusion of 0-43 M-KCl or 0-43 M-NaCl at 2 ml./min for 2 hr. The salivary flow rate was depressed during the infusion of potassium chloride into both intact sheep and adrenalectomized sheep. As the salivary flow was unchanged by sodium chloride infusion it was concluded that the potassium ion was responsible for the decrease in flow and that this effect was not mediated through any of the adrenal hormones. The highly significant negative correlation between plasma potassium concentration and salivary flow throughout all potassium infusions indicated that the extent to which the salivary flow was depressed varied with the degree of hyperkalaemia. Except for situations where mineralocorticoid levels were likely to be elevated the concentrations of sodium and potassium in the saliva were positively correlated with the plasma concentrations of these ions. The salivary bicarbonate concentration of the saliva was negatively related to flow. The chloride concentration of the saliva was negatively correlated with salivary flow during all potassium chloride infusions. (+info)
Serum amylase isoenzymes in patients undergoing operation for ruptured and non-ruptured abdominal aortic aneurysm.
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OBJECTIVE: Previous work has suggested that hyperamylasemia in patients who undergo operation for ruptured abdominal aortic aneurysm (AAA) is associated with poor outcome. The aims of this study were to determine, for the first time, the source of serum amylase in such patients and to examine the prognostic significance of amylase isoenzyme expression. METHODS: This study was designed as a prospective clinical and laboratory study. The study consisted of 40 patients who underwent operation for ruptured AAA and 10 patients who underwent operation for non-ruptured AAA. The main outcome measures were serum total and pancreatic and salivary amylase activities determined with enzymatic colorimetric assay before operation and 6 hours after aortic clamp release. RESULTS: Five of 40 patients (12.5%) with rupture and one of 10 patients (10%) with non-rupture had elevated total amylase levels before operation, and seven of 31 patients (23%) with rupture and five of 10 patients (50%) with non-rupture had elevated total amylase levels after operation. The preoperative salivary amylase (P =.05) and postoperative pancreatic amylase (P <.02) levels were significantly lower in ruptured AAA as compared with non-ruptured AAA. The preoperative salivary amylase level was significantly lower in non-survivors of rupture, such that a level equal to or less than 45 U/L was associated with death in 11 of 13 patients (85%). CONCLUSION: These data do not support previous works that suggest that hyperamylasemia is associated with poor outcome in ruptured AAA. By contrast, a low preoperative salivary amylase level was associated with increased mortality in ruptured AAA and may be a marker of the severity of shock. (+info)
The effect of shot biopsy on behavior, salivary cortisol, and heart rate in slaughter pigs.
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This paper describes behavioral and physiological responses of pigs to shot biopsy, an experimental method used to study muscle tissue processes or to predict meat quality. One biopsy sample from the longissimus muscle was obtained from 23-wk-old gilts (n = 10) using a cannula connected to a captive bolt. Ten other gilts were used as a control and received a sham shot. One week later, a second biopsy was taken from the same gilts. Behavioral and salivary cortisol responses to both biopsies were similar (P > .10). Pigs flinched in response to the biopsies. Salivary cortisol concentrations were increased (P < .05) 15 min after the biopsy as compared with pretreatment levels, but absolute levels were not different (P > .10) from the control group. In both biopsy and control groups, heart rate increased (P < .001) in response to the presence of the technician. In response to the first biopsy, heart rate increased (P < .01) as compared with the rate during the 5-s period before the biopsy, but heart rate did not increase in response to the second biopsy. The biopsy pigs showed a decrease (P < .05) in initiating contact with the technician in the second test. We conclude that shot biopsy had a significant acute effect on behavior and heart rate. Therefore, the usefulness of this technique in studies in which the behavioral and heart rate responses are measured is limited. (+info)