Rheological properties of saliva substitutes containing mucin, carboxymethylcellulose or polyethylenoxide

Apparent viscosities at different shear rates were measured for 3 types of saliva substitutes: (a) mucin-containing saliva; (b) substitutes based upon carboxymethylcellulose (CMC), and (c) solution of polyethylenoxide (PEO). The apparent viscosities were compared with those of human whole saliva. Human whole saliva and mucin-containing saliva substitutes appeared to be similar in their rheological properties. Both types of solution are viscoelastic solutions and adjust their apparent viscosities to their biological functions. Preparations containing CMC or PEO are non-Newtonian liquids. From this study it is concluded that mucin-containing saliva substitutes appear to be the best substitutes for natural saliva, as far as rheological properties are concerned

The problem of collecting different body fluids from drivers in the surveys

Objectives: It is not easy to obtain a blood sample from drivers at the roadside for use in epidemiological studies. Therefore, use of saliva samples has become popular. On the other hand, in studies in injured drivers, obtaining a saliva sample can be problematic, e.g. because of injuries. When drug concentrations in blood and saliva need to be compared e.g. in risk calculations, results from different matrices need to be comparable. Because of the different recoveries with saliva collection devices, saliva:blood ratios should be determined for each collection device. Methods: Drug concentrations in blood and saliva samples from different studies (Rosita-2, roadside surveys) were analysed by GC-MS and UPLC-MS/MS and the results were compared for different drugs. Results: While for some drugs like diazepam, relatively good correlation can be observed (r2 = 0.98, n=23, Saliva blood ratio 0.033), for most other drugs there is a very wide scatter when comparing saliva and blood concentrations. These findings confirm those of other published studies. One of the possible explanations is the trapping of basic drugs in saliva because of the pH effects. Conclusion: The correlation between drug concentrations in saliva and whole blood is poor for most drugs. It might be advisable to use whole blood also in a roadside surveys

Evaluation of the effect of tyrothricin on beta-hemolytic streptococci in salva. Part I: The effect of salvia upon bacteria. Part II: Effect of tyrothricin on the New York 5 strain of Streptococcus pyogenes in saliva

Part II of thesis by Brancato, Noyes, and Swift. Part I of thesis by Swift. Thesis (M.A.)--Boston UniversityThe antibacterial effect of saliva has been known for many years. Still the exact nature of the antagonistic action of saliva upon bacteria is as yet unsettled. Most workers agree, however, that the salivary bacterial inhibitory action is brought about in at least six ways: The first antibacterial effect is changes in pH, which affect the growth of oral organisms. Furthermore, this change in pH is dependent on diet and on the type of organisms in the oral cavity. The second is the mechanical factors involved, for saliva not only flushes bacteria from the mouth, but dilutes the number of organisms as well. The third is the antibacterial action of the cellular components in saliva. The leukocytes in saliva have a phagocytic action, and the non-phagocytic epithelial cells slough off in sheets, carrying with them thousands of organisms which have lodged in the partially turned edges of the necrotic cells . The fourth antibacterial action is ascribed to the presence of immune bodies in the saliva which lyse or agglutinate the oral bacteria. The fifth is the presence of oral bacteria which are antagonistic to new invaders. And the sixth is the presence of enzymes that lyse some oral bacteria or alter their cell membranes thereby inhibiting further growth. In recent years a great deal of investigation has been made to ascribe the enzymatic effect as the chief antibacterial agent in saliva; however, contradictory work has been done to try to attribute the chief antibacterial action of salivary cocci. Indeed the antibacterial effect of saliva is not always present, for the bacteriostatic effect of saliva is variable from day to day and from individual to individual. The only way of reducing the number of oral bacteria is to add to the saliva an antibiotic. Tyrothricin was used. In an attempt to delineate the range of concentration of tyrothricin per ml. effective against the New York 5 strain of Streptococcus pryogenes in saliva, this experiment was carried out. It was molded after the unpublished work of Belding concerning the effect of tyrothricin on the Oxford Strain of Staphylococcus aureus in saliva. The required inoculum of approximately one million organisms per ml was obtained by growing cultures of the streptococci under uniform conditions and setting up a table of the absorbances and viable cell counts, from which dilution factors for further cultures could be estimated. Controls were set up for determining possible inhibition of tyrothricin and/or test organisms by the various diluting fluids including saliva. Final concentrations per ml of 10, 25, 50, 75, and 100 µg of tyrothricin integrated with saliva and an approximated number of streptococci were plated out after 30 and 60 minutes exposure periods and were counted after 24 and 48 hours of incubation at 37°C. Whereas 1 µg per ml of tyrothricin reduced markedly the number of streptococci suspended in water during a 30 minute exposure period and 10 µg per ml, under similar conditions, caused complete inhibition, 10 µg per ml of the antibiotic was ineffective against this test organism suspended in saliva during a 30 minute exposure period but caused about an 80 per cent reduction in viable organisms during 60 minutes exposure. The length of the exposure period necessary for effective inhibition varied inversely with the concentration of tyrothricin per ml, 100 µg per ml causing a 98 per cent reduction of viable organisms during an exposure period of 1 minute. For the 30 minute exposure period, the quantity of tyrothricin effective against this strain of streptococci mixed in saliva would fall in the 10 µg - 25 µg per ml range and for shorter exposure periods, the concentration per ml would have to be greater. Cultures completely negative during 24 hours incubation at 37°C, showed a typical growth during 48 hours. This is considered indicative of the bacteriostatic action of tyrothricin which, prolonged, resulted in the death of large numbers of the streptococci. The results which were obtained in these experiments serve chiefly to point out the way for further work and to form a basis for the general conclusions listed below: 1. The action of tyrothricin on bacteria is inhibited by saliva to a large degree. 2. The minimal amounts of tyrothricin necessary to produce complete inhibition of growth of Streptococcus pyogenes in saliva is between 25 and 50 µg per ml acting for 30 minutes. 3. There is an effective reduction of Streptococcus pyogenes in saliva by concentrations of tyrothricin between 10 and 25 µg per ml acting for 30 minutes. 4. Tyrothricin acts immediately upon contact with Streptococcus pyogenes. 5. The action of tyrothricin on Streptococcus pyogenes in saliva is apparently bacteriostatic and not of a permanent nature as manifested by growth of atypical colonies during 48 hours incubation. 6. Tyrothricin above a concentration of 50 µg per ml had a definite reducing effect on the bacterial population of this saliva. 7. Saliva also has a bactericidal or bacteriostatic (or both) action against Streptococcus pyogenes

Disposable collection kit for rapid and reliable collection of saliva.

ObjectivesTo describe and evaluate disposable saliva collection kit for rapid, reliable, and reproducible collection of saliva samples.MethodsThe saliva collection kit comprised of a saliva absorbent swab and an extractor unit was used to retrieve whole saliva samples from 10 subjects. The accuracy and precision of the extracted volumes (3, 10, and 30 μl) were compared to similar volumes drawn from control samples obtained by passive drool. Additionally, the impact of kit collection method on subsequent immunoassay results was verified by assessing salivary cortisol levels in the samples and comparing them to controls.ResultsThe recovered volumes for the whole saliva samples were 3.85 ± 0.28, 10.79 ± 0.95, and 31.18 ± 1.72 μl, respectively (CV = 8.76%) and 2.91 ± 0.19, 9.75 ± 0.43, and 29.64 ± 0.91 μl, respectively, (CV = 6.36%) for the controls. There was a close correspondence between the salivary cortisol levels from the saliva samples obtained by the collection kit and the controls (R(2)  > 0.96).ConclusionsThe disposable saliva collection kit allows accurate and repeatable collection of fixed amounts of whole saliva and does not interfere with subsequent measurements of salivary cortisol. The simple collection process, lack of elaborate specimen recovery steps, and the short turnaround time (<3 min) should render the kit attractive to test subjects and researchers alike

Rheological Behavior of Food Emulsions Mixed with Saliva: Effect of Oil Content, Salivary Protein Content, and Saliva Type

In this paper, we studied the effect of saliva on the rheological properties of ß-lactoglobulin- and lysozyme-stabilized emulsions, prepared at pH¿=¿6.7 in relation to variation of emulsions- and saliva-related parameters. The effect of oil¿volume fraction (2.5% w/w to 10% w/w), salivary protein concentration (0.1 to 0.8 mg ml¿1), and the use of both stimulated and unstimulated saliva was investigated. Viscosity and storage modulus were measured before (¿ emul and G¿emul, respectively) and after addition of saliva (¿ mix and G¿mix). To better estimate the changes due to saliva-induced flocculation of the emulsions, the ratios ¿ mix/¿ emul, G¿mix/G¿emul were calculated. In addition, tan ¿ (=the ratio of the loss and storage moduli) was investigated to evaluate the viscoelastic behavior of the emulsion/saliva mixtures. Increasing the oil¿volume fraction and salivary protein concentration resulted in an increase in ¿ mix/¿ emul and G¿mix/G¿emul, while a decrease in tan ¿ of the emulsion/saliva mixtures is occurring. When compared with unstimulated saliva, mixing ß-lactoglobulin-stabilized emulsions with stimulated saliva led to a reduction in ¿ mix/¿ emul and G¿mix/G¿emul, and an augment of tan ¿ at all measured deformations. In case of lysozyme-stabilized emulsions, the use of stimulated saliva increased G¿mix/G¿emul for ¿

Bioinformatics advances in saliva diagnostics

There is a need recognized by the National Institute of Dental & Craniofacial Research and the National Cancer Institute to advance basic, translational and clinical saliva research. The goal of the Salivaomics Knowledge Base (SKB) is to create a data management system and web resource constructed to support human salivaomics research. To maximize the utility of the SKB for retrieval, integration and analysis of data, we have developed the Saliva Ontology and SDxMart. This article reviews the informatics advances in saliva diagnostics made possible by the Saliva Ontology and SDxMart

Oral microbiota carriage in patients with multibracket appliance in relation to the quality of oral hygiene

Background: The present study aimed to investigate the prevalence of oral microbiota (Candida species (spp.), Streptococcus mutans, and Lactobacilli) in patients with multibracket (MB) appliances in relation to the quality of oral hygiene. Saliva and plaque samples were collected from three groups of 25 patients each (good oral hygiene (GOH), poor oral hygiene (POH), and poor oral hygiene with white spot lesions (POH/WSL)). Counts of colony forming units (CFU) of the investigated oral microbiota were compared using Chi-square and Mann–Whitney U tests. Results: Both saliva and plaque samples showed a high prevalence of Candida spp. in all patients (saliva: 73.4 %, plaque: 60.9 %). The main Candida species was C. albicans. The salivary CFU of Candida spp. in the GOH group was significantly lower than that in the POH group (p?=?0.045) and POH/WSL group (p?=?0.011). S. mutans was found in the saliva and plaque samples of all patients. Lactobacilli were found in the saliva samples of all patients and in 90.7 % of the plaque samples. In the saliva samples, the CFU of Lactobacilli were more numerous in the POH and POH/WSL groups than in the GOH group (p?=?0.047). Conclusions: The investigated sample of patients showed a high carriage of oral Candida spp. Patients with WSL formation during MB appliance treatment exhibited higher counts of Candida and Lactobacilli compared with patients with good oral hygiene. Independent of oral hygiene quality, S. mutans was detected in all patients

The serlogical specificity of the lectin from Lens culinaris

Lens culinaris, the common lentil, contains a lectin which has been shown to be specific for a glycoprotein saliva antigen and a glycolipoprotein serum antigen. Both the saliva and serum precipitin reactions with the lectin are directly inhibited with saccharides, especially those related to D-mannose. Electrophoresis of the serum antigen showed that it migrates as three bands, while appearing as a single band in double diffusion precipitin patterns. Quantitative studies of the saliva antigen levels by hemagglutination inhibition titration indicated a polygenic, quantitative mode of inheritance with a minimum heritability of O. 34. Blood group ABH secretor individuals were found to have a significantly lower mean saliva antigen level than nonsecretor individuals. The lectins from Pisum sativum and Canavaliafiensiformis formed precipitin bands of identity with L.culinaris lectin against saliva. C. ensiformis and L. culinaris lectins exhibited precipitin bands of partial identity against serum; and P. sativum and L. culinaris lectins exhibited a pattern of identity against serum. In addition, precipitin patterns of partial identity with the non-H lectin from Lotus tetragonolobus has been demonstrated. Using Ulex europaeus lectin in hemagglutination inhibition experiments with saliva from blood group O secretor individuals, a minimum heritability of approximately 0.40 for H antigen levels was found. A higher frequency of nonsecretor individuals was observed in the Black population compared with the White population

DNA Typing Compatibility with a One Step Saliva Screening Test

Screening a substrate for bodily fluids is an extremely important step for locating areas that may contain DNA. Several different methods have been developed for saliva (1). The Phadebas® Forensic Press (PFP) test is a presumptive saliva test that utilizes a preloaded paper that will react with the enzyme amylase, a component of saliva (2-5). Because of its ability to screen for amylase while simultaneously locating stains, the PFP may prove to be an effective, rapid method for screening. However it is important to assess whether the PFP introduces any inhibitors (7) to downstream processing such as PCR amplification. Based on previous studies, we hypothesize that the PFP will provide a rapid and sensitive method for locating multiple saliva stains simultaneously, without introducing inhibitors to DNA profiling. To test the limitations of PFP as well as evaluated its effects on DNA profiling we first created a dilution series of saliva ranging from neat to 1:5000. After this we preformed sensitivity tests on an indirect method, UV degraded samples and washed samples as well as with bodily fluid mixtures. Once all sensitivity tests were done, cuttings were taken from the substrate and PFP paper and analyzed for DNA. Tests found that the sensitivity ranges of the PFP were between 1:10 and 1:1000, indirect tests were less sensitive than direct, all bodily fluid mixtures were detected, and UV degraded samples took more time to react. In addition our DNA results confirmed our hypothesis that PFP does not inhibit DNA and is a useful method for locating stains. This project was funded by NSFREU Grant DBI 1262832

The combined effects of salivas and occlusal indicators on occlusal contact forces

Background Some occlusal detection products are designed for use on dry teeth, but this is not always achieved. Others are suited for dry and wet applications. Objective The objective of this study is to assess the combined effects, on occlusal contact forces, of two previously studied affecting variables—occlusal detection products and saliva. Methods We used a full‐arch dentiform with three occlusal detection products (an articulating film, an articulation paper and T‐Scan) in combination with human (HS) and an artificial saliva. The maxillary arch assembly, weighing ~54 N (the maximum bite force), was lowered onto (occlusion) and lifted off (disclusion) of the mandibular arch through 10 cycles by a mechanical testing machine. The forces and moments acting on the mandibular arch were continuously recorded by a load cell that supported it. Results The maximum values of Flateral (the in‐occlusal plane component of the occlusal contact force) were analysed by occlusion/disclusion separately using one‐way ANOVA, with factor for group type to identify the significant effect of salivas on products, effect of products, effect of salivas with products, effect of human saliva. A difference in occlusion and/or in disclusion was considered different. Statistical differences (P < 0.0001) in Flateral were found in: dry product vs product + HS, dry product vs product + artificial saliva (with articulating film and T‐Scan) and HS vs product + HS (with articulation paper and T‐Scan). Conclusion All products were affected by the salivas, except articulation paper by artificial saliva