930 resultados para Saliva


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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 eVect 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 unaVected 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.

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Based on previous research which shows parallelism between the saliva and blood lactate response during incremental exercise, we hypothesized that a "maximum salivary lactate steady state" (saliva-MLSS) might exist. Thus, the aim of the present investigation was to establish 1) which lower limit for the increase in salivary lactate concentration during a constant workload (i.e., from the 10th to the 20th min) test could be used to determine the saliva-MLSS and 2) if the exercise intensity corresponding to the saliva-MLSS is identical to that evoking the (blood) MLSS. Twelve male amateur athletes of mean (+/-SD) age 24+/-5 year were selected for the study. Based on the results of a previous maximal cycle ergometer test for lactate threshold (LT) determination, each subject performed consecutive constant workload tests of 20-min duration on separate days for MLSS determination, Blood and saliva (25 mu l) samples were collected at 0, 10, and 20 min during the tests for lactate determination. A Student's t-test for paired data demonstrated that a salivary lactate increase of 0.8 mM corresponded to the saliva-MLSS. At this value, indeed, no significant differences were observed between the mean (V) over dot O-2, and W values corresponding to the MLSS and the saliva-MLSS. In conclusion, the present findings indicate that 0.8 mM is the lower limit for the increase in saliva lactate concentration during a constant load test and thus is that which might be used as a reference to determine saliva-MLSS. Furthermore, saliva-MLSS might be used as an alternative to MLSS determination in blood samples.

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Polyphenols are widely present in fruits, vegetables, cereals and beverages. Their study gained scientific interest because of their beneficial effects on health. Although there is currently no official dietary recommendation for polyphenol intake, health professionals recommend the consumption of 5-8 daily portions of fruits and vegetables. This is not always achieved and, despite possible causes associated to practical schedule difficulties, the aversive bitter and astringent sensations associated to polyphenols may also lead to avoidance. As such, a better understanding on mechanisms responsible for differences among people, in polyphenol oral perception, is needed for promoting healthier choices. Saliva has been linked to polyphenol consumption. We have previously observed, in animal models, changes in salivary proteome induced by tannin-enriched diets. Moreover, differences in astringency perception were attributed to differences in salivary protein composition. In a recent experiment, we observed differences among individuals with dissimilar tannic-acid perception: people with high sensitivity for the oral sensations elicited by tannins have higher amounts of salivary cystatins and lower capacity to maintain their levels after tannic-acid ingestion. Additionally, and similarly to previous studies, salivary amylase was observed to be involved in tannin perception. In this presentation, oral cavity characteristics influencing the perception of polyphenol-containing foods will be discussed.

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Understanding the relationship between diet, physical activity and health in humans requires accurate measurement of body composition and daily energy expenditure. Stable isotopes provide a means of measuring total body water and daily energy expenditure under free-living conditions. While the use of isotope ratio mass spectrometry (IRMS) for the analysis of 2H (Deuterium) and 18O (Oxygen-18) is well established in the field of human energy metabolism research, numerous questions remain regarding the factors which influence analytical and measurement error using this methodology. This thesis was comprised of four studies with the following emphases. The aim of Study 1 was to determine the analytical and measurement error of the IRMS with regard to sample handling under certain conditions. Study 2 involved the comparison of TEE (Total daily energy expenditure) using two commonly employed equations. Further, saliva and urine samples, collected at different times, were used to determine if clinically significant differences would occur. Study 3 was undertaken to determine the appropriate collection times for TBW estimates and derived body composition values. Finally, Study 4, a single case study to investigate if TEE measures are affected when the human condition changes due to altered exercise and water intake. The aim of Study 1 was to validate laboratory approaches to measure isotopic enrichment to ensure accurate (to international standards), precise (reproducibility of three replicate samples) and linear (isotope ratio was constant over the expected concentration range) results. This established the machine variability for the IRMS equipment in use at Queensland University for both TBW and TEE. Using either 0.4mL or 0.5mL sample volumes for both oxygen-18 and deuterium were statistically acceptable (p>0.05) and showed a within analytical variance of 5.8 Delta VSOW units for deuterium, 0.41 Delta VSOW units for oxygen-18. This variance was used as “within analytical noise” to determine sample deviations. It was also found that there was no influence of equilibration time on oxygen-18 or deuterium values when comparing the minimum (oxygen-18: 24hr; deuterium: 3 days) and maximum (oxygen-18: and deuterium: 14 days) equilibration times. With regard to preparation using the vacuum line, any order of preparation is suitable as the TEE values fall within 8% of each other regardless of preparation order. An 8% variation is acceptable for the TEE values due to biological and technical errors (Schoeller, 1988). However, for the automated line, deuterium must be assessed first followed by oxygen-18 as the automated machine line does not evacuate tubes but merely refills them with an injection of gas for a predetermined time. Any fractionation (which may occur for both isotopes), would cause a slight elevation in the values and hence a lower TEE. The purpose of the second and third study was to investigate the use of IRMS to measure the TEE and TBW of and to validate the current IRMS practices in use with regard to sample collection times of urine and saliva, the use of two TEE equations from different research centers and the body composition values derived from these TEE and TBW values. Following the collection of a fasting baseline urine and saliva sample, 10 people (8 women, 2 men) were dosed with a doubly labeled water does comprised of 1.25g 10% oxygen-18 and 0.1 g 100% deuterium/kg body weight. The samples were collected hourly for 12 hrs on the first day and then morning, midday, and evening samples were collected for the next 14 days. The samples were analyzed using an isotope ratio mass spectrometer. For the TBW, time to equilibration was determined using three commonly employed data analysis approaches. Isotopic equilibration was reached in 90% of the sample by hour 6, and in 100% of the sample by hour 7. With regard to the TBW estimations, the optimal time for urine collection was found to be between hours 4 and 10 as to where there was no significant difference between values. In contrast, statistically significant differences in TBW estimations were found between hours 1-3 and from 11-12 when compared with hours 4-10. Most of the individuals in this study were in equilibrium after 7 hours. The TEE equations of Prof Dale Scholler (Chicago, USA, IAEA) and Prof K.Westerterp were compared with that of Prof. Andrew Coward (Dunn Nutrition Centre). When comparing values derived from samples collected in the morning and evening there was no effect of time or equation on resulting TEE values. The fourth study was a pilot study (n=1) to test the variability in TEE as a result of manipulations in fluid consumption and level of physical activity; the magnitude of change which may be expected in a sedentary adult. Physical activity levels were manipulated by increasing the number of steps per day to mimic the increases that may result when a sedentary individual commences an activity program. The study was comprised of three sub-studies completed on the same individual over a period of 8 months. There were no significant changes in TBW across all studies, even though the elimination rates changed with the supplemented water intake and additional physical activity. The extra activity may not have sufficiently strenuous enough and the water intake high enough to cause a significant change in the TBW and hence the CO2 production and TEE values. The TEE values measured show good agreement based on the estimated values calculated on an RMR of 1455 kcal/day, a DIT of 10% of TEE and activity based on measured steps. The covariance values tracked when plotting the residuals were found to be representative of “well-behaved” data and are indicative of the analytical accuracy. The ratio and product plots were found to reflect the water turnover and CO2 production and thus could, with further investigation, be employed to identify the changes in physical activity.

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Stimulated human whole saliva (WS) was used to study the dynamics of papain hydrolysis at defined pH, ionic strength and temperature with the view of reducing an acquired pellicle. A quartz crystal microbalance with dissipation (QCM-D) was used to monitor the changes in frequency due to enzyme hydrolysis of WS films and the hydrolytic parameters were calculated using an empirical model. The morphological and conformational changes of the salivary films before and after enzymatic hydrolysis were characterized by atomic force microscopy (AFM) imaging and grazing angle infrared spectroscopy (GA-FTIR) spectra, respectively. The characteristics of papain hydrolysis of WS films were pH-, ionic strength- and temperature-dependent. The WS films were partially removed by the action of enzyme, resulting thinner and smoother surfaces. The IR data suggested that hydrolysis-induced deformation did not occur onto the remnants salivary films. The processes of papain hydrolysis of WS films can be controlled by properly regulating pH, ionic strength and temperature.

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- Historically by default we have created an operational environment where the key AOD issue has been testing and not safety, behaviour and culture. - The tail wagging the dog. - We risk loosing the point the point. - Many people traditionally want to hear a paper about, testing, technology or the pros and cons of saliva VS urine testing etc . - This is a good example of how the workplace alcohol and other drugs area has been politicised, commercialised, simplified and myopic.

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Abstract Background: The importance of quality-of-life (QoL) research has been recognised over the past two decades in patients with head and neck (H&N) cancer. The aims of this systematic review are to evaluate the QoL status of H&N cancer survivors one year after treatment and to identify the determinants affecting their QoL. Methods: Pubmed, Medline, Scopus, Sciencedirect and CINAHL (2000–2011) were searched for relevant studies, and two of the present authors assessed their methodological quality. The characteristics and main findings of the studies were extracted and reported. Results: Thirty-seven studies met the inclusion criteria, and the methodological quality of the majority was moderate to high. While patients of the group in question recover their global QoL by 12 months after treatment, a number of outstanding issues persist – deterioration in physical functioning, fatigue, xerostomia and sticky saliva. Age, cancer site, stage of disease, social support, smoking, feeding tube placement and alcohol consumption are the significant determinants of QoL at 12 months, while gender has little or no influence. Conclusions: Regular assessments should be carried out to monitor physical functioning,degree of fatigue, xerostomia and sticky saliva. Further research is required to develop appropriate and effective interventions to deal with these issues, and thus to promote the patients’ QoL.

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Background: Xanthine oxidase (XO) is a complex molybdeno-flavoprotein occurring with high activity in the milk fat globule membrane (MFGM) in all mammalian milk and is involved in the final stage of degradation of purine nucleotides. It catalyzes the sequential oxidation of hypoxanthine to xanthine and uric acid, accompanied by production of hydrogen peroxide and superoxide anion. Human saliva has been extensively described for its composition of proteins, electrolytes, cortisol, melatonin and some metabolites such as amino acids, but little is known about nucleotide metabolites. Method: Saliva was collected with swabs from babies; at full-term 1-4 days, 6-weeks, 6-months and 12-months. Unstimulated fasting (morning) saliva samples were collected directly from 77 adults. Breast milk was collected from 24 new mothers. Saliva was extracted from swabs and ultra-filtered. Nucleotide metabolites were analyzed by RP-HPLC with UV-photodiode array and ESI-MS/MS. XO activity was measured as peroxide production from hypoxanthine. Bacterial inhibition over time was assessed using CFU/mL or OD. Results: Median concentrations (μmol/L) of salivary nucleobases and nucleosides for neonates/6-weeks/6-months/12-months/adult respectively were: uracil 5.3/0.8/1.4/0.7/0.8, hypoxanthine 27/7.0/1.1/0.8/2.0, xanthine 19/7.0/2.0/2.0/2.0, adenosine 12/7.0/0.9/0.8/0.1, inosine 11/5.0/0.3/0.4/0.2, guanosine 7.0/6.0/0.5/0.4/0.1, uridine 12/0.8/0.3/0.9/0.4. Deoxynucleosides and dihydropyrimidines concentrations were essentially negligible. XO activity (Vmax:mean ± SD) in breast milk was 8.9 ± 6.2 μmol/min/L and endogenous peroxide was 27 ± 12 μmol/L; mixing breast milk with neonate saliva generated ~40 μmol/L peroxide,which inhibited Staphylococcus aureus. Conclusions: Salivary metabolites, particularly xanthine/hypoxanthine, are high in neonates, transitioning to low adult levels between 6-weeks to 6-months (p < 0.001). Peroxide occurs in breast milk and is boosted during suckling as an antibacterial system.

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The aim of this study was to investigate the influence of low-dose bovine colostrum protein concentrate (CPC) supplementation on selected immune variables in cyclists. Twenty-nine highly trained male road cyclists completed an initial 40-km time trial (TT(40)) and were then randomly assigned to either a supplement (n = 14, 10 g bovine CPC/day) or placebo group (n = 15, 10 g whey protein concentrate/day). After 5 wk of supplementation, the cyclists completed a second TT(40). They then completed 5 consecutive days of high-intensity training (HIT) that included a TT(40), followed by a final TT(40) in the following week. Venous blood and saliva samples were collected immediately before and after each TT(40), and upper respiratory illness symptoms were recorded over the experimental period. Compared with the placebo group, bovine CPC supplementation significantly increased preexercise serum soluble TNF receptor 1 during the HIT period (bovine CPC = 882 +/- 233 pg/ml, placebo = 468 +/- 139 pg/ml; P = 0.039). Supplementation also suppressed the postexercise decrease in cytotoxic/suppressor T cells during the HIT period (bovine CPC = -1.0 +/- 2.7%, placebo = -9.2 +/- 2.8%; P = 0.017) and during the following week (bovine CPC = 1.4 +/- 2.9%, placebo = -8.2 +/- 2.8%; P = 0.004). Bovine CPC supplementation prevented a postexercise decrease in serum IgG(2) concentration at the end of the HIT period (bovine CPC = 4.8 +/- 6.8%, P = 0.88; placebo = -9.7 +/- 6.9%, P = 0.013). There was a trend toward reduced incidence of upper respiratory illness symptoms in the bovine CPC group (P = 0.055). In summary, low-dose bovine CPC supplementation modulates immune parameters during normal training and after an acute period of intense exercise, which may have contributed to the trend toward reduced upper respiratory illness in the bovine CPC group.

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Introduction: Although advances in treatment modalities have improved the survival of head and neck (H&N) cancer patients over recent years, survivors’ quality of life (QoL) could be impaired for a number of reasons. The investigation of QoL determinants can inform the design of supportive interventions for this population. Objectives: To examine the QoL of H&N cancer survivors at 1 year after treatment and to identify potential determinants affecting their QoL. Methods: A systematic search of literature was done in December 2011 in five databases: Pubmed, Medline, Scopus, Sciencedirect and CINAHL, using combined search terms ‘head and neck cancer’, ‘quality of life’, ‘health-related quality of life’ and ‘systematic review’. The methodological qualities of selected studies were assessed by two reviewers using predefined criteria. The study characteristics and results were abstracted and summarized. Results: Thirty-seven studies met all inclusion criteria with methodological quality from moderate to high. The global QoL of H&N cancer survivors returned to baseline at 1 year after treatment. Significant improvement showed in emotional functioning while physical functioning, xerostomia, sticky/insufficient saliva, and fatigue were consistently worse at 12 months compared with baseline. Age, cancer sites and stages, social support, smoking, presence of feeding tube are significant QoL determinants at 12 months. Conclusions: Although the global QoL of H&N cancer survivors recover by 12 months after treatment, problems with physical functioning, fatigue, xerostomia and sticky saliva persist. Regular assessment should be carried out to monitor these problems. Further research is required to develop appropriate and effective interventions for this population.

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Objectives To investigate the frequency of the ACTN3 R577X polymorphism in elite endurance triathletes, and whether ACTN3 R577X is significantly associated with performance time. Design Cross-sectional study. Methods Saliva samples, questionnaires, and performance times were collected for 196 elite endurance athletes who participated in the 2008 Kona Ironman championship triathlon. Athletes were of predominantly North American, European, and Australian origin. A one-way analysis of variance was conducted to compare performance times between genotype groups. Multiple linear regression analysis was performed to model the effect of questionnaire variables and genotype on performance time. Genotype and allele frequencies were compared to results from different populations using the chi-square test. Results Performance time did not significantly differ between genotype groups, and age, sex, and continent of origin were significant predictors of finishing time (age and sex: p < 5 × 10−6; continent: p = 0.003) though genotype was not. Genotype and allele frequencies obtained (RR 26.5%, RX 50.0%, XX 23.5%, R 51.5%, X 48.5%) were found to be not significantly different from Australian, Spanish, and Italian endurance athletes (p > 0.05), but were significantly different from Kenyan, Ethiopian, and Finnish endurance athletes (p < 0.01). Conclusions Genotype and allele frequencies agreed with those reported for endurance athletes of similar ethnic origin, supporting previous findings for an association between 577X allele and endurance. However, analysis of performance time suggests that ACTN3 does not alone influence endurance performance, or may have a complex effect on endurance performance due to a speed/endurance trade-off.

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Aim: To describe the recruitment, ophthalmic examination methods and distribution of ocular biometry of participants in the Norfolk Island Eye Study, who were individuals descended from the English Bounty mutineers and their Polynesian wives. Methods: All 1,275 permanent residents of Norfolk Island aged over 15 years were invited to participate, including 602 individuals involved in a 2001 cardiovascular disease study. Participants completed a detailed questionnaire and underwent a comprehensive eye assessment including stereo disc and retinal photography, ocular coherence topography and conjunctival autofluorescence assessment. Additionally, blood or saliva was taken for DNA testing. Results: 781 participants aged over 15 years were seen (54% female), comprising 61% of the permanent Island population. 343 people (43.9%) could trace their family history to the Pitcairn Islanders (Norfolk Island Pitcairn Pedigree). Mean anterior chamber depth was 3.32mm, mean axial length (AL) was 23.5mm, and mean central corneal thickness was 546 microns. There were no statistically significant differences in these characteristics between persons with and without Pitcairn Island ancestry. Mean intra-ocular pressure was lower in people with Pitcairn Island ancestry: 15.89mmHg compared to those without Pitcairn Island ancestry 16.49mmHg (P = .007). The mean keratometry value was lower in people with Pitcairn Island ancestry (43.22 vs. 43.52, P = .007). The corneas were flatter in people of Pitcairn ancestry but there was no corresponding difference in AL or refraction. Conclusion: Our study population is highly representative of the permanent population of Norfolk Island. Ocular biometry was similar to that of other white populations. Heritability estimates, linkage analysis and genome-wide studies will further elucidate the genetic determinants of chronic ocular diseases in this genetic isolate.

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Background Recurrent protracted bacterial bronchitis (PBB), chronic suppurative lung disease (CSLD) and bronchiectasis are characterised by a chronic wet cough and are important causes of childhood respiratory morbidity globally. Haemophilus influenzae and Streptococcus pneumoniae are the most commonly associated pathogens. As respiratory exacerbations impair quality of life and may be associated with disease progression, we will determine if the novel 10-valent pneumococcal-Haemophilus influenzae protein D conjugate vaccine (PHiD-CV) reduces exacerbations in these children. Methods A multi-centre, parallel group, double-blind, randomised controlled trial in tertiary paediatric centres from three Australian cities is planned. Two hundred six children aged 18 months to 14 years with recurrent PBB, CSLD or bronchiectasis will be randomised to receive either two doses of PHiD-CV or control meningococcal (ACYW(135)) conjugate vaccine 2 months apart and followed for 12 months after the second vaccine dose. Randomisation will be stratified by site, age (<6 years and >= 6 years) and aetiology (recurrent PBB or CSLD/bronchiectasis). Clinical histories, respiratory status (including spirometry in children aged >= 6 years), nasopharyngeal and saliva swabs, and serum will be collected at baseline and at 2, 3, 8 and 14 months post-enrolment. Local and systemic reactions will be recorded on daily diaries for 7 and 30 days, respectively, following each vaccine dose and serious adverse events monitored throughout the trial. Fortnightly, parental contact will help record respiratory exacerbations. The primary outcome is the incidence of respiratory exacerbations in the 12 months following the second vaccine dose. Secondary outcomes include: nasopharyngeal carriage of H. influenzae and S. pneumoniae vaccine and vaccine-related serotypes; systemic and mucosal immune responses to H. influenzae proteins and S. pneumoniae vaccine and vaccine-related serotypes; impact upon lung function in children aged >= 6 years; and vaccine safety. Discussion As H. influenzae is the most common bacterial pathogen associated with these chronic respiratory diseases in children, a novel pneumococcal conjugate vaccine that also impacts upon H. influenzae and helps prevent respiratory exacerbations would assist clinical management with potential short- and long-term health benefits. Our study will be the first to assess vaccine efficacy targeting H. influenzae in children with recurrent PBB, CSLD and bronchiectasis.

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Hypothesis Melatonin synthesis, which is directly controlled by the central circadian pacemaker indicates the circadian phase better than rectal temperature. Methods: Thirty four men (16-32 years, 7 morning, 13 neither, 14 evening types) performed a constant routine (24-26-hr bedrest, < 30 lux, 18-20°C, hourly isocaloric diet). Salivary melatonin level was determined hourly and rectal temperature was continuously recorded. Results: The nadir of rectal temperature occurred 1.5 hr (P = 0.017), the onset of melatonin synthesis 3 hr earlier (P < 0.0001) in morning than in evening types. Morningness was not related to the quantitative but significantly to the temporal parameters, closer to those of melatonin than of rectal temperature. Conclusions: The melatonin onset is a more reliable indicator of the diurnal type than the nadir of rectal temperature. As morningness has been associated with intolerance to shiftwork, melatonin profiling provides a suitable basis for the establishment of directed preventive measures.

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Saliva is a crucial biofluid for oral health and is also of increasing importance as a non-invasive source of disease biomarkers. Salivary alpha-amylase is an abundant protein in saliva, and changes in amylase expression have been previously associated with a variety of diseases and conditions. Salivary alpha-amylase is subject to a high diversity of post-translational modifications, including physiological proteolysis in the oral cavity. Here we developed methodology for rapid sample preparation and non-targeted LC-ESI-MS/MS analysis of saliva from healthy subjects and observed an extreme diversity of alpha-amylase proteolytic isoforms. Our results emphasize the importance of consideration of post-translational events such as proteolysis in proteomic studies, biomarker discovery and validation, particularly in saliva. (C) 2012 Elsevier B.V. All rights reserved.