Saliva analysis in the clinical setting: revisiting an underused diagnostic tool

Spicy Recipe for At-Home Diagnostics: Smart Salivary Sensors for Point-of-Care Diagnosis of Jaundice

Even though significant advances have been made, there is still a lack of reliable sensors capable of noninvasively monitoring bilirubin and diagnosing jaundice as the most common neonatal disease, particularly at the point-of-care (POC) where blood sampling from infants is accompanied by serious challenges and concerns. Herein, for the first time, using an easy-to-fabricate/use assay, we demonstrate the capability of curcumin embedded within paper for noninvasive optical monitoring of bilirubin in saliva. The highly selective sensing of the developed sensor toward bilirubin is attributed to bilirubin photoisomerization under blue light exposure, which can selectively restore the bilirubin-induced quenched fluorescence of curcumin. We also fabricated an IoT-enabled hand-held optoelectronic reader to measure and quantify the fluorescence and color signals of our sensor. Clinical analysis on the saliva of 18 jaundiced infants by using our developed smart salivary sensor proved that it is amenable to be widely exploited in POC applications for bilirubin monitoring as there are good correlations between its results with those of reference methods in saliva and blood. Meeting all WHO's REASSURED criteria by our developed sensor makes it a highly promising sensor for smart noninvasive diagnosis and therapeutic monitoring of jaundice, hepatitis, and other bilirubin-induced neurologic diseases at the POC.

Detection of Propionic Acids Trapped in Thin Zeolite Layer Using Thermal Desorption Analysis

Volatile organic compounds (VOCs) have recently received considerable attention for the analysis and monitoring of different biochemical processes in biological systems such as humans, plants, and microorganisms. The advantage of using VOCs to gather information about a specific process is that they can be extracted using different types of samples, even at low concentrations. Therefore, VOC levels represent the fingerprints of specific biochemical processes. The aim of this work was to develop a sensor based on a photoionization detector (PID) and a zeolite layer, used as an alternative analytic separation technique for the analysis of VOCs. The identification of VOCs occurred through the evaluation of the emissive profile during the thermal desorption phase, using a stainless-steel chamber for analysis. Emission profiles were evaluated using a double exponential mathematical model, which fit well if compared with the physical system, describing both the evaporation and diffusion processes. The results showed that the zeolite layer was selective for propionic acid molecules if compared to succinic acid molecules, showing linear behavior even at low concentrations. The process to define the optimal adsorption time between the propionic acid molecules was performed in the range of 5 to 60 min, followed by a thermal desorption process at 100 °C. An investigation of the relationship between the evaporation and diffusion rates showed that the maximum concentration of detected propionic acid molecules occurred in 15 min. Other analyses were performed to study how the concentration of VOCs depended on the desorption temperature and the volume of the analysis chamber. For this purpose, tests were performed using three analysis chambers with volumes of 25 × 10-6, 50 × 10-6, and 150 × 10-6 m3 at three different desorption temperatures of 20 °C, 50 °C, and 100 °C, respectively. The results demonstrated that the evaporation rate of the VOCs increased rapidly with an increasing temperature, while the diffusion rate remained almost constant and was characterized by a slow decay time. The diffusion ratio increased when using a chamber with a larger volume. These results highlight the capabilities of this alternative technique for VOC analysis, even for samples with low concentrations. The coupling of a zeolite layer and a PID improves the detection selectivity in portable devices, demonstrating the feasibility of extending its use to a wide range of new applications.

Peri-implant Bone Healing: Its Basic Osteogenesis and Biomarkers

The continuous sequence of bone healing phases starts off with osteoconduction to the implant surface, depending on the migration of osteogenic cells. Osteoneogenesis ensues resulting in a mineralised interfacial matrix and is followed by bone remodelling to the implant interface at discrete sites. Dental implant drilling procedure and placement produce osseous defect which is filled by blood. Within seconds, blood proteins are adsorbed onto the implant surface and platelets are activated resulting in the release of cytokines and growth factors. Further platelet aggregation initiates osteoconduction to the surface, followed by osteoneogenesis, forming an extracellular matrix. Subsequently, remodelling creates a bone to implant interface which can be explained through distance and contact osteogenesis. The dental implant surface has been shown to influence osteoconduction by modifying protein properties and adsorption around the implant. Salivary biomarkers may be considered as a specific and sensitive diagnostic tool to detect these changes in protein expressions after implant placement. Thus, the purpose of this narrative review is to provide a detailed account of the bone healing mechanism associated with dental implant placement, as well as how the implant surface architecture and protein release play a role in bone healing, and the potential use of saliva to detect these biomarkers.

Changes in Salivary Amylase and Glucose in Diabetes: A Scoping Review

BACKGROUND AND OBJECTIVE

Diabetes mellitus (DM) is a common long-term disease which can be related with salivary amylase levels. DM has recently been associated with salivary amylase diagnostics that could further impair diagnoses in the diabetic population, as well as being an interesting alternative to traditional methods of determine glucose levels. The main advantage of this method is related to the fact that it is a fast diagnostic method. The DM population experiences changes to their metabolism which affects their salivary parameters, making this an alternative procedure for diagnosis and follow-up of the illness due to the non-invasive nature of salivary analyzes. The objective of this review is to summarize the evidence regarding the changes in salivary amylase and glucose levels, and their relationship with blood markers of glycemic control used in clinical settings such as blood glucose and glycated hemoglobin. The differences in salivary amylase levels depending on the method of saliva collection under fasting or non-fasting conditions. The changes in salivary amylase depends on the type of diabetes, the type of insulin treatment or the quality of glycemic control.

CONCLUSIONS

Salivary amylase concentration is increased in diabetic patients in most of the studies and salivary glucose concentration in all studies in both fasting and non-fasting (post-prandial) conditions. Salivary amylase and glucose concentration represent potential non-invasive biomarkers to evaluate glycemic control and clinical management of diabetic patients, although it is necessary to evaluate the influence of potential modulating factors such as age, duration diseases, sex and the effects of pharmacological treatments in these outcomes which remained to be elucidated.

Association of Salivary Statherin, Calcium, and Proline-Rich Proteins on Oral Hygiene: A Cross-Sectional Study

Background

Saliva, as a complex biofluid, plays a pivotal role in maintaining oral health and tooth integrity. There has been inconsistent data available on the relationship between salivary parameters and oral health. This study aims to investigate the association between salivary statherin, acidic proline-rich proteins (aPRP), and calcium with oral hygiene status.

Methods

One hundred and eighty-eight healthy subjects aged between 18 and 50 years with varying oral hygiene status who gave consent to participate were included in this cross-sectional study. The subjects were recruited from primary oral health care of MAHSA University. Oral hygiene of all the participants was measured using Oral Hygiene Index–Simplified (OHI-S). Stimulated saliva collected using paraffin wax was analyzed for salivary statherin, aPRP, and calcium. The relationship between salivary statherin, aPRP, and calcium levels with OHI-S was assessed using Spearman's Rank correlation coefficient; the strength of relationship was assessed by multiple linear regression analysis.

Results

The study found a weak positive correlation (r = 0.179, p = 0.014) between salivary statherin and OHI-S; weak negative correlation (r = −0.187, p = 0.010) between salivary aPRP and OHI-S; and moderate negative correlation between salivary statherin and salivary aPRP levels (r = −0.50, p < 0.001) which were statistically significant.

Conclusion

Poor oral hygiene is associated with increased statherin and reduced aPRP levels in saliva. Thus, these salivary components may have a role in predicting oral hygiene status.

Periodontal condition, changes in salivary biochemical parameters, and oral health-related quality of life in patients with anorexia and bulimia nervosa

BACKGROUND

Anorexia and bulimia nervosa can have significant effects on oral health. Assessment of enzyme concentrations in saliva can be useful for obtaining information on molecular biomarkers for the prevention, monitoring, and diagnosis of oral diseases. This study investigated the periodontal condition, changes in salivary biochemical parameters, and oral health-related quality of life (OHRQoL) in patients with anorexia and bulimia nervosa.

METHODS

The study comprised 60 women patients who attended a Brazilian medical school. Participants were divided into two groups: patients with anorexia and bulimia nervosa (ABN; n = 30) and control patients (CN; n = 30). Oral clinical examinations were carried out to evaluate the periodontal condition by Community Periodontal Index, and interviews using the Oral Health Impact Profile (OHIP-14) were conducted to assess OHRQoL. Saliva samples were collected for the evaluation of salivary concentrations of total protein, alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), and thiobarbituric acid reactive substance (TBARS), and salivary flow rate.

RESULTS

Periodontal condition in the ABN group was significantly worse than that in the CN group. The ABN group showed significantly higher salivary concentrations of total protein, AST, ALT, and LDH than the CN group. There was no significant difference in the salivary concentrations of TBARS among the groups. The OHIP-14 score was higher in the ABN group than in the CN group.

CONCLUSION

Anorexia and bulimia nervosa are associated with poor periodontal condition, elevated salivary concentrations of total protein, AST, ALT, and LDH, decreased salivary flow rate and a significant adverse impact on OHRQoL.

A New Approach for the Diagnosis of Systemic and Oral Diseases Based on Salivary Biomolecules

Early diagnosis represents the target of contemporary medicine and has an important role in the prognosis and further treatment. Saliva is a biofluid that generated a high interest among researchers due to its multiple advantages over other body fluids. The multitude of components that can act as biomarkers influenced the existing technologies to develop protocols that could allow saliva to become the new noninvasive diagnostic method. Saliva as a diagnostic tool can bring substantial addition to the diagnostic armamentarium, providing important information about oral and general health. The diagnostic applications of saliva extended and had a rapid evolution due to the advancement in salivaomics. The present review summarizes the latest researches in saliva-related studies and explores the information and correlations that saliva can offer regarding the systemic and oral diseases, highlighting its great potential of diagnosis. It is expected that in the future specific guidelines and results regarding the salivary diagnostics are to be available, together with high-sensitivity and specificity tests for multiple systemic and oral diseases.

Synergy between nanomaterials and volatile organic compounds for non-invasive medical evaluation

This article is an overview of the present and ongoing developments in the field of nanomaterial-based sensors for enabling fast, relatively inexpensive and minimally (or non-) invasive diagnostics of health conditions with follow-up by detecting volatile organic compounds (VOCs) excreted from one or combination of human body fluids and tissues (e.g., blood, urine, breath, skin). Part of the review provides a didactic examination of the concepts and approaches related to emerging sensing materials and transduction techniques linked with the VOC-based non-invasive medical evaluations. We also present and discuss diverse characteristics of these innovative sensors, such as their mode of operation, sensitivity, selectivity and response time, as well as the major approaches proposed for enhancing their ability as hybrid sensors to afford multidimensional sensing and information-based sensing. The other parts of the review give an updated compilation of the past and currently available VOC-based sensors for disease diagnostics. This compilation summarizes all VOCs identified in relation to sickness and sampling origin that links these data with advanced nanomaterial-based sensing technologies. Both strength and pitfalls are discussed and criticized, particularly from the perspective of the information and communication era. Further ideas regarding improvement of sensors, sensor arrays, sensing devices and the proposed workflow are also included.

Altered Salivary Profile in Heavy Smokers and its Possible Connection to Oral Cancer

Saliva is the first biological fluid to encounter inhaled cigarette smoke, whose numerous carcinogens and oxidants are responsible for the oral cancer so prevalent among smokers. Whole saliva, collected from 25 consenting heavy smokers and from a control group of 25 age- and gender-matched non-smokers, was subjected to sialochemical, biochemical, immunological and oxidative analyses. The mean flow rate was significantly higher in smokers than in non-smokers, as were the median activity value of superoxide dismutase (SOD) and the total salivary antioxidant capacity (ImAnOx) (by 32% and 12%, respectively, p=0.05). The salivary carbonyl concentration (an oxidative stress indicator) was significantly higher by 126% (p=0.0006) among smokers, while lactate dehydrogenase, albumin, total immunoglobulin G, and the metalloproteinases MMP-2 and MMP-9 concentrations were significantly lower in the smokers, by 86% (p=0.003), 65% (p=0.003), 61% (p=0.048), 35% (p=0.005) and 55% (p=0.035), respectively. Apparently, the oral cavity's salivary antioxidant system fails to cope with the severe attack of reactive oxygen species originating in cigarette smoke. Moreover, various other salivary functional and protective parameters also decreased among the smokers. Hence, further research aimed at examining the possibility of administration of agents as antioxidants or saliva substitutes to the oral cavity of smokers should be considered.

The effects of storage time and temperature on the stability of salivary phosphatases, transaminases and dehydrogenase

OBJECTIVES

To investigate the influence of temperature and storage time on salivary acid phosphatase (ACP), tartrate-resistant acid phosphatase (TRAP), alkaline phosphatase (ALP), aspartate aminotransferase (AST) and alanine aminotransferase (ALT) and lactate dehydrogenase (LDH).

DESIGN

Unstimulated whole expectorated saliva was collected from healthy men and women subjects (n=26) between 8 and 10a.m. The saliva samples were centrifuged, and the supernatants were measured for ACP, TRAP, ALP, AST, ALT and LDH activities immediately (without freezing) [baseline values] and after time intervals of 3, 7, 14 and 28days (d) of storage at -20°C and -80°C using spectrophotometric methods The influence of storage time was analyzed by one-way ANOVA followed by the Dunnett post-test, while the paired Student's-t-test was used to compare the differences between the temperature (p<0.05).

RESULTS

There was significant decline in the activities of all enzymes at -20°C with increasing storage time. This decrease was relevant from day 14 onward for the majority of the enzymes, with the exception of AST. After day 28, the more sensitive enzymes were ALP and LDH, which showed residual activity of 39% and 16%, respectively, compared with baseline values. There were considerable, but insignificant changes, in the activities of all enzymes after storage at -80°C for 28days.

CONCLUSIONS

Frozen samples should be kept at -80°C to preserve these activities, but there are restrictions for the enzymes ALP, ALT and LDH. Storage of samples at -20°C could introduce high error variance in measured activities.

Optimal reference genes for RT-qPCR normalization in the newborn

It is difficult to identify reliable reference genes for transcriptomic analyses in biofluids such as saliva. This situation is particularly relevant for the newborn population, where rapid development is associated with dynamic changes in gene expression. Real-time gene expression monitoring holds great promise for elucidating disrupted pathways that result in morbidities unique to this population, such as retinopathy of prematurity, but its impact depends on identifying stable and consistently expressed genes across a wide range of gestational ages. We extracted total RNA from 400 neonatal saliva samples (postconceptional ages: 32 5/7 to 48 2/7 weeks), converted it to cDNA, and pre-amplified and analyzed it by qPCR for three commonly used reference genes, ACTB, GAPDH, and YWHAZ. Relative quantification was determined using the Δ Ct method. Data were analyzed as a whole and also stratified by age and sex. Descriptive statistics and homogeneity of variance were performed to identify optimal reference genes. Data analyzed from all ages and both sexes showed significant expression variation for ACTB, while GAPDH and YWHAZ showed greater stability. Male infants exhibited increased expression variation compared to females for ACTB, but neither GAPDH nor YWHAZ showed significant variance for either sex. We suggest that ACTB is an unreliable reference gene for the newborn population. Males showed significantly more variation in ACTB expression compared to females, which suggests a sex-specific developmental role for this biomarker. By contrast, GAPDH and YWHAZ were less variable and therefore preferable for use in neonates. Our findings may improve the use of reference genes for the RT-qPCR platform in the newborn over a wide range of gestational ages, thereby minimizing the likelihood of erroneous interpretation of gene expression during rapid growth, development, and differentiation.

Salivary and serum levels of tumor necrosis factor-alpha in oral lichen planus: a systematic review and meta-analysis study

OBJECTIVE

Tumor necrosis factor-α (TNF-α) has a role in the progression of the oral lichen planus (OLP). The aim of this meta-analysis study was to evaluate the salivary and serum TNF-α levels in patients with OLP.

STUDY DESIGN

We searched in the databases of PubMed/Medline, Science direct, Scopus, Web of Science, and Cochrane Library for studies reported from 1983 to 2016. All studies were checked for evaluation of salivary and serum levels of TNF-α in patients with OLP compared with healthy controls.

RESULTS

Twelve studies were included in the meta-analysis. The mean difference of 7 studies reporting salivary TNF-α levels in patients with OLP versus healthy controls was 25.90 pg/mL (95% confidence interval [CI] 15.31-36.49; P < .00001) and 7 studies reporting serum TNF-α levels was 1.65 pg/mL (95% CI -0.82 to 4.11; P = .19).

CONCLUSIONS

In patients with OLP, the higher levels of TNF-α in saliva compared with serum suggest that measurement of this marker in saliva may be more useful than in serum for determining diagnostic and therapeutic aims.

Clinical evaluation of salivary carbohydrate antigen 125 and leptin in controls and parotid tumours

OBJECTIVES

We determined the correlation between saliva and serum for CA125 and leptin, and evaluated their clinical screening potential for parotid tumours.

SUBJECTS AND METHODS

Serum, acid-stimulated bilateral parotid saliva and chewing-stimulated whole saliva were collected and measured the levels of CA125 and leptin with electrochemiluminescence immunoassay and enzyme-linked immunosorbent assay for healthy controls and patients with unilateral parotid tumour. Intra- and intergroup comparisons were made among them. Correlations and receiver operating curve analyses were also conducted.

RESULTS

There was no correlation between salivary and serum CA125 (r = -0.157-0.265, P > 0.05), while significant correlation was found for leptin (r = 0.219-0.761, P < 0.05). Leptin levels in tumour parotid saliva and CA125 levels in whole saliva were elevated significantly (P < 0.001) and showed screening potential for parotid tumours. Salivary and serum leptin levels were significantly higher in women than in men (P < 0.001).

CONCLUSIONS

Salivary CA125 might originate primarily from salivary gland and tumour rather than from blood, while salivary leptin might originate from both blood and salivary gland. Multiple sources might contribute to the significantly elevated CA125 in whole saliva. Whole saliva CA125 and parotid saliva leptin reflected the occurrence of parotid tumours, while serum CA125 and leptin did not. Salivary CA125 and leptin could not distinguish malignant parotid tumours. When detecting leptin level, the influence of subjects' sex must be considered.

Nanoscale Sensor Technologies for Disease Detection via Volatolomics

The detection of many diseases is missed because of delayed diagnoses or the low efficacy of some treatments. This emphasizes the urgent need for inexpensive and minimally invasive technologies that would allow efficient early detection, stratifying the population for personalized therapy, and improving the efficacy of rapid bed-side assessment of treatment. An emerging approach that has a high potential to fulfill these needs is based on so-called "volatolomics", namely, chemical processes involving profiles of highly volatile organic compounds (VOCs) emitted from body fluids, including breath, skin, urine and blood. This article presents a didactic review of some of the main advances related to the use of nanomaterial-based solid-state and flexible sensors, and related artificially intelligent sensing arrays for the detection and monitoring of disease with volatolomics. The article attempts to review the technological gaps and confounding factors related to VOC testing. Different ways to choose nanomaterial-based sensors are discussed, while considering the profiles of targeted volatile markers and possible limitations of applying the sensing approach. Perspectives for taking volatolomics to a new level in the field of diagnostics are highlighted.

Hybrid volatolomics and disease detection

This Review presents a concise, but not exhaustive, didactic overview of some of the main concepts and approaches related to "volatolomics"-an emerging frontier for fast, risk-free, and potentially inexpensive diagnostics. It attempts to review the source and characteristics of volatolomics through the so-called volatile organic compounds (VOCs) emanating from cells and their microenvironment. It also reviews the existence of VOCs in several bodily fluids, including the cellular environment, blood, breath, skin, feces, urine, and saliva. Finally, the usefulness of volatolomics for diagnosis from a single bodily fluid, as well as ways to improve these diagnostic aspects by "hybrid" approaches that combine VOC profiles collected from two or more bodily fluids, will be discussed. The perspectives of this approach in developing the field of diagnostics to a new level are highlighted.

Salivary diagnostics using a portable point-of-service platform: a review

Clinical diagnostics can be improved by faster and more accessible disease detection. Our laboratory has developed a point-of-service (POS) device capable of rapid, sensitive, automated, and multiplexed biomarker detection that uses human saliva instead of other biofluids. Here, we review the technology that led to the development of this POS device. This POS technology can advance clinical diagnostics by saving time because of faster diagnosis, saving money because of a shorter hospital stay, and ultimately improving clinical care.

Salivary alkaline phosphatase and calcium in caries-active type II diabetes mellitus patients: An in vivo study

Background:

Diabetes Mellitus is a metabolic syndrome, affecting the oral health in various ways with dental caries being one of the most common problems encountered. Saliva is one of the most abundant secretions in the human body with a variety of natural protective and defence molecules bathing the oral cavity maintaining equilibrium. Its collection is easy and non-invasive.

Aims:

To compare and evaluate salivary alkaline phosphatase levels and calcium ion levels between caries active type II diabetes mellitus patients and non-diabetics.

Materials and Methods:

This study was carried out on caries-active age and gender matched 60 non-diabetic and 60 patients with known Type II diabetes mellitus subjects of age group 25-50 years with DMFT index >10. Saliva sample was collected to analyse for alkaline phosphatase enzyme and concentration of calcium ions using Agappe kits.

Statistical Analysis:

Student ‘t’ test was used to correlate the salivary electrolyte concentration in non- diabetic and diabetic patients with dental caries. A ‘P’ value of 0.05 or less was considered significant. Results are presented as mean ± standard deviation (X ± SD).

Results:

The alkaline phosphatase (ALP) activity in saliva was higher in diabetic patients when compared to that of non-diabetic patients with salivary calcium ions were significantly higher in non-diabetic individuals.

Conclusion:

Diabetes Mellitus patients are more prone to dental caries, hence require intervention to improve the quality of saliva.

The human volatilome: volatile organic compounds (VOCs) in exhaled breath, skin emanations, urine, feces and saliva

Breath analysis is a young field of research with its roots in antiquity. Antoine Lavoisier discovered carbon dioxide in exhaled breath during the period 1777-1783, Wilhelm (Vilém) Petters discovered acetone in breath in 1857 and Johannes Müller reported the first quantitative measurements of acetone in 1898. A recent review reported 1765 volatile compounds appearing in exhaled breath, skin emanations, urine, saliva, human breast milk, blood and feces. For a large number of compounds, real-time analysis of exhaled breath or skin emanations has been performed, e.g., during exertion of effort on a stationary bicycle or during sleep. Volatile compounds in exhaled breath, which record historical exposure, are called the 'exposome'. Changes in biogenic volatile organic compound concentrations can be used to mirror metabolic or (patho)physiological processes in the whole body or blood concentrations of drugs (e.g. propofol) in clinical settings-even during artificial ventilation or during surgery. Also compounds released by bacterial strains like Pseudomonas aeruginosa or Streptococcus pneumonia could be very interesting. Methyl methacrylate (CAS 80-62-6), for example, was observed in the headspace of Streptococcus pneumonia in concentrations up to 1420 ppb. Fecal volatiles have been implicated in differentiating certain infectious bowel diseases such as Clostridium difficile, Campylobacter, Salmonella and Cholera. They have also been used to differentiate other non-infectious conditions such as irritable bowel syndrome and inflammatory bowel disease. In addition, alterations in urine volatiles have been used to detect urinary tract infections, bladder, prostate and other cancers. Peroxidation of lipids and other biomolecules by reactive oxygen species produce volatile compounds like ethane and 1-pentane. Noninvasive detection and therapeutic monitoring of oxidative stress would be highly desirable in autoimmunological, neurological, inflammatory diseases and cancer, but also during surgery and in intensive care units. The investigation of cell cultures opens up new possibilities for elucidation of the biochemical background of volatile compounds. In future studies, combined investigations of a particular compound with regard to human matrices such as breath, urine, saliva and cell culture investigations will lead to novel scientific progress in the field.

Salivary and serum analysis in children diagnosed with pneumonia

The aim of the current study was to evaluate specific markers for pneumonia by using a non-invasive assessment of inflammatory/oxidative biomarkers in saliva accompanying a routine serum analysis. No study evaluating saliva of children with pneumonia has been published previously. Salivary analysis was performed in 15 children diagnosed with lobar pneumonia and in a parallel group of 16 children matching in age and gender in whom there was no respiratory illness, and compared to the serum analysis obtained routinely in both groups of children. Salivary flow rate was lower in the patients' group as was uric acid concentration (by 60%). Increase in salivary concentrations of almost all parameters analyzed was found: Ca, P, and Mg concentrations were higher in the patients' group by 23%, 55%, and 33%, respectively, while LDH, total protein amylase and albumin concentrations were higher by 275%, 79%, and 42%, respectively. In the serum, white cell counts and neutrophils were significantly higher, and sodium level significantly lower in the patients' group. Compositional changes were in the range of 3-80% while the saliva alterations were more profound, in the range of 42-275%. The results demonstrated in the current study indicate salivary analysis as a potentially novel tool for children with pneumonia. Human salivary collection and analysis is a non-invasive tool that could provide additional information for diagnosis and follow-up of pneumonia, especially in children. This is especially beneficial for pediatric patients, as salivary collection is simple, non-invasive, and patient-friendly.

Salivary biomarker analysis complementing regular clinical examination

AIM

Tools for the diagnosis and evaluation of the severity and prognosis of periodontitis are currently insufficient. The aim of the current study was to find an array of salivary biomarkers that would be both sensitive and specific enough to be used as a complement to regular clinical examination. Furthermore, we investigated salivary markers of successful periodontal treatment to elucidate the underlying mechanism of disease.

PATIENTS & METHODS

Saliva was collected from periodontitis patients during illness and following successful disease termination. Parameters measured included sodium, potassium, chloride, calcium, phosphate, magnesium, total protein, Alb, LDH, amylase, IL-1α, uric acid and carbonyls.

RESULTS

Seven of the parameters analyzed were significantly altered when the disease is active and may be considered biomarkers.

CONCLUSION

Salivary composition reflects disease severity and response to therapy, suggesting the efficacy of saliva monitoring for periodontal disease status and care.

Preference changes of adult outpatients for giving saliva, urine and blood for clinical testing after actual sample collection

PURPOSE

Patients' preferences of the type of sample collections for clinical testing are currently unknown. The aims of this study were: (1) to assess patients' preferences of three types of samples for clinical testing (saliva, urine and blood) both before and after collection and (2) to assess whether prior experiences with collection of saliva impacted patients responses.

METHODS

Adult outpatients underwent collection of one sample each of saliva, urine and blood. Patients' perceptions of comfort, convenience and easiness were assessed in pre-collection and post-collection questionnaires.

RESULTS

Post-collection, patients' endorsement of saliva as being the "most comfortable" and "most convenient" significantly declined (pre vs. post, 61.5% vs. 37.5% and 73.1% vs. 42.3%). However, saliva was still endorsed as the "most convenient" post-collection (compared to urine 33.7% and blood 24.0%). Although not statistically significant, the proportion of patients who changed their response in terms of what sample was "easiest to collect at home" was considerably higher in the group with vs. without prior experience giving saliva (54.6% vs. 32.6%, p=0.19 Fisher's exact test).

CONCLUSIONS

Overall, saliva remained as the most highly preferred sample to donate despite a decline in patients' preferences of saliva donation after sample collection. The results of the study are promising for future widespread patient acceptance of saliva as a diagnostic fluid.

The effect of academic exam stress on mucosal and cellular airway immune markers among healthy and allergic individuals

Research suggests that psychological stress can exacerbate allergies, but relatively little is known about the effect of stress on mucosal immune processes central to allergic pathophysiology. In this study, we quantified vascular endothelial growth factor (VEGF), interferon gamma (IFN-γ), and interleukin-4 concentrations in saliva (S) and exhaled breath condensate (EBC) during final exams and at midsemester among 23 healthy and 21 allergic rhinitis individuals. IFN-γs decreased during exams for both groups while VEGF(EBC) increased (and increases in VEGFs were a trend). Elevated negative affect ratings predicted higher VEGF(EBC) in allergic individuals. IFN-γ(EBC) increased in healthy individuals early during exams and then decreased, while allergic individuals showed a decrease in IFN-γ(EBC) throughout final exams. These findings suggest that psychological stress can suppress cellular immune function among allergic individuals while increasing VEGF.

Effects of psychosocial stress on the pattern of salivary protein release

Previous research suggests that acute stress can increase the release of immune-relevant proteins in saliva. However, no attempts have been made to examine a wider range of salivary proteins in response to stress. In this study, we identified and quantified changes in the pattern of salivary protein release in a 45 min time period following the Trier Social Stress Test (TSST) in 12 asthmatic and 13 healthy participants. Proteins were separated using sodium dodecyl sulfate polyacrylamide gel electrophoresis. The relative protein amounts were quantified using the Image J software (NIH), and identified and characterized using mass spectroscopy. Negative affect was increased immediately after stress in both groups. The results showed that alpha amylase, cystatin S and light chain IgA were increased after the TSST and significant increases in glutathione S-transferase and prolactin inducible protein were also observed. Asthma patients showed responses similar to healthy controls, but had a tendency toward overall lower alpha amylase levels. Our findings suggest that a variety of proteins relevant to mucosal immunity are elevated following acute psychosocial stress, including glutathione S-transferase and prolactin inducible protein, which had not been characterized in this context before.

Validation of three commercially available immunoassays for quantification of IgA, IgG, and IgM in porcine saliva samples

The objectives of this study were to perform the optimization and validation of three commercially available immunoassays for the measurement of IgA, IgG, and IgM (Igs) in porcine saliva samples and to determinate if their concentrations may be used to distinguish healthy from diseased animals. Intra and inter assay coefficients of variation were lower than 15% in all cases. All methods showed good linearity and recovery; and detection limits were low enough to detect Igs levels in healthy and diseased animals. The clinical validation showed an increase statistically significant (P<0.05) in the group of diseased animals versus healthy pigs. Therefore, these assays may be used in porcine saliva samples, in addition, the measurement of Igs in saliva could be a practical tool, simple and minimally invasive, to evaluate the humoral immune status of pigs.

Intraoperative bleeding during open flap debridement and regenerative periodontal surgery

BACKGROUND

The objective of this study was to measure the intraoperative bleeding during periodontal flap surgery.

METHODS

Patients scheduled for periodontal surgery were recruited for this study. Data regarding smoking habits, general health, and medications were collected. The amount of the local anesthetic that was injected was then recorded, as well as the number of teeth in the operative field and the duration of the procedure. During surgery, the liquids from the oral cavity were suctioned and collected into a sterile empty vial. To calculate the net amount of blood volume in the liquids, colorimetric assay using capillary blood fructosamine as a reference molecule was used.

RESULTS

Twenty-six patients were included in this study. The amount of blood lost during the procedure ranged from 6.0 to 145.1 mL, with an overall mean of 59.47 ± 38.2 mL. Patients taking aspirin (acetylsalicylic acid) showed mean blood loss of 43.26 ± 31.5 mL, whereas the mean blood loss among patients that did not use this medication was higher (65.4 ± 39.4 mL) but not statistically significant. Local anesthetic amount, surgical field size, and the operation duration did not relate to blood-loss volume. The mean blood loss among current smokers was significantly higher (96.47 ± 44.2 mL) compared to former (12 ± 8.4 mL) or never (54.74 ± 30.5 mL, P = 0.011) smokers.

CONCLUSION

The results of the current study support previous papers and confirm that blood loss during periodontal surgery is minimal.

Salivary monitoring related to major surgery

BACKGROUND

Prolonged surgical procedures involving stress, extended general anaesthesia and a long pre-surgical fasting period may have systemic effects such as alterations in saliva flow rate and composition. These may compromise the patient's electrolytes and fluid balance and cause dehydration, systemic stress and oxidative changes.

PATIENTS AND METHODS

Saliva was collected prior and following surgery from 20 patients and 20 control subjects. The saliva samples were analysed for flow rates and levels of the following: calcium (Ca), magnesium (Mg), total protein, albumin and lactate dehydrogenase (LDH), total antioxidant status (TAS), uric acid (UA), superoxide dismutase (SOD), carbonyls, matrix metalloproteinases (MMPs) -2, -3 and -9 and heat shock proteins (HSPs) 70 and 90.

RESULTS

Salivary levels of Ca, Mg, protein, albumin and LDH were higher in post-surgical patients by 70% (P = 0·002), 88% (P = 0·0001), 120% (P = 0·13), 111% (P = 0·039) and 492% (P = 0·006) respectively than that in healthy controls. Salivary antioxidants in the surgical patients were higher while salivary carbonyls remained unchanged. Salivary TAS levels in pre- and post-surgical patients were higher by 63% (P = 0·001) and 85% (P = 0·0001) respectively, UA concentrations by 92% (P = 0·014) and 81% (P = 0·036) respectively and SOD values by 47% (P = 0·61) and 112% (P = 0·049) respectively. Salivary concentrations of MMP3 were higher in pre- and post-surgical patients by 23% (P = 0·067) and 30% (P = 0·044) respectively.

CONCLUSIONS

Local salivary, oral and systemic-induced alterations should be prevented. Moreover, salivary collection and analysis may be a new, efficient tool in the monitoring of patients undergoing major surgery. Further related research is necessary.

Oxidative stress biomarkers in urine and plasma of rabbits with partial bladder outlet obstruction

What's known on the subject? and What does the study add? It has been known that there is an increase of oxidative damage in the bladder tissues of animals after PBOO. However, no reliable oxidative stress biomarkers in either urine or plasma have been available for the assessment of the severity of PBOO. This study clearly demonstrated that the levels of oxidative stress biomarkers are increased in urine and plasma of the rabbits with PBOO.

OBJECTIVE

To investigate oxidative stress and oxidative damage biomarkers in urine and plasma after partial bladder outlet obstruction (PBOO) in rabbits.

MATERIALS AND METHODS

In all, 16 male New Zealand White rabbits were separated equally into four groups: a control group and PBOO-treated groups for 2, 4 and 8 weeks. The oxidative stress biomarkers assessed included urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG) and plasma malondialdehyde (MDA). We also measured the total antioxidant capacity (TAC) in blood plasma. 8-OHdG, MDA and TAC were measured at both the beginning and indicated time points of the experimental design.

RESULTS

There was no significant difference in body weight among rabbits in the four groups. However, there was a significant increase in bladder weight after 2 weeks of PBOO. After 4 and 8 weeks of PBOO, there was an additional significant increase in bladder weight in all three groups. There was no difference in blood creatinine levels among the groups. In the 4- and 8-week PBOO groups, there was a significant increase of 8-OHdG in urine and of MDA in plasma, while there was a significant decrease in TAC in plasma.

CONCLUSION

The results showed that oxidative stress could be detected in the plasma and urine of rabbits after 4 and 8 weeks of PBOO, and not only from bladder tissue as previously reported. Thus, there could be an easy and alternative way to evaluate bladder function by analysis of urine and/or plasma. Additionally, rabbits with chronic PBOO showed an increase in systemic oxidative stress, which could be a novel starting point for examining the link between the lower urinary tract symptoms/benign prostate hyperplasia and metabolic syndrome in future studies.

Altered Salivary Redox Homeostasis in Patients with Systemic Sclerosis

Objective.

Oxidative stress has been implicated in the pathogenesis of systemic sclerosis (SSc). Our objective was to determine whether SSc is associated with altered redox homeostasis in human saliva.

Methods.

Study participants were 70 women with SSc and 120 female controls. 8-hydroxy-2’-deoxyguanosine (8-OHdG), 8-epi-prostaglandin F 2α (8-epi-PGF2α), and total protein carbonyls were assayed by ELISA to quantify oxidative damage to nucleic acids, lipids, and proteins, respectively, in whole nonstimulated saliva.

Results.

We observed a significantly positive association between salivary log protein carbonyls and SSc in a crude statistic (OR 9.06, p < 0.0001), and multivariable model adjusted for log 8-OHdG, log 8-epi-PGF2α, and antioxidant exposure (OR 9.26, p < 0.0001). No significant association was noted between SSc and salivary log 8-epi-PGF2α or log 8-OHdG.

Conclusion.

Salivary redox homeostasis is perturbed in patients with SSc and may inform on the pathophysiology and presence of the disease (biomarkers) and efficacy of therapeutic interventions.

Salivary antioxidants and metalloproteinases in juvenile idiopathic arthritis

Juvenile idiopathic arthritis (JIA) is the most common autoimmune inflammatory disease in children; joint inflammation is the hallmark of the disease. Thirty-five children with JIA were studied, of whom 26 had active disease and 14 were receiving anti-TNF therapy (5 with Infliximab, 9 with Etanercept). Sixteen healthy controls also were studied. Saliva samples were obtained for analysis of anti-oxidant status, metalloproteinases (MMPs) and sialochemistry. The total antioxidant status was significantly higher in the saliva of all JIA patients, whether treated (P = 0.014) or not treated (P = 0.038) with anti-TNF agents. The increase in antioxidant status (TAS) in the saliva of the active patients was nearly two times higher than that of non-active patients (P = 0.01). MMP levels were significantly lower in JIA patients than in controls. MMP-9, MMP-3 and MMP-2 were lower in JIA patients without anti-TNF treatment by 36.7% (P = 0.01), 30.0% (P = 0.0001) and 10.7% (P = 0.0001), respectively. A greater reduction in MMP levels was observed in the group of patients treated with anti-TNF drugs: MMP-9, MMP-3 and MMP-2 were lower than in controls by 51.1% (P = 0.0001), 61.5% (P = 0.0001) and 55.4% (P = 0.0001), respectively. Children with JIA exhibited a significantly higher salivary antioxidant activity and significantly lower MMP levels. Anti-TNF treatment was associated with a further decrease in MMP levels in the saliva of JIA patients while an active state of JIA was associated with a further increase in the salivary antioxidant activity. Anti-TNF treatment may modulate the degradation process during the course of arthritis by inhibition of the activity of MMP.

Salivary analysis of oral cancer biomarkers

BACKGROUND

Oral cancer is a common and lethal malignancy. Direct contact between saliva and the oral cancer lesion makes measurement of tumour markers in saliva an attractive alternative to serum testing.

METHODS

We tested 19 tongue cancer patients, measuring the levels of 8 salivary markers related to oxidative stress, DNA repair, carcinogenesis, metastasis and cellular proliferation and death.

RESULTS

Five markers increased in cancer patients by 39-246%: carbonyls, lactate dehydrogenase, metalloproteinase-9 (MMP-9), Ki67 and Cyclin D1 (CycD1) (P< or =0.01). Three markers decreased by 16-29%: 8-oxoguanine DNA glycosylase, phosphorylated-Src and mammary serine protease inhibitor (Maspin) (P< or =0.01). Increase in salivary carbonyls was profound (by 246%, P=0.012); alterations in CycD1 (87% increase, P=0.000006) and Maspin (29% decrease, P=0.007) were especially significant. Sensitivity values of these eight analysed markers ranged from 58% to 100%; specificity values ranged from 42% to 100%. Both values were especially high for the CycD1 and Maspin markers, 100% for each value of each marker. These were also high for carbonyls, 90% and 80%, respectively, and for MMP-9, 100% and 79%, respectively.

CONCLUSION

The significance of each salivary alteration is discussed. As all alterations correlated with each other, they may belong to a single carcinogenetic network. Cancer-related changes in salivary tumour markers may be used as a diagnostic tool for diagnosis, prognosis and post-operative monitoring.

Salivary profile and oxidative stress in children and adolescents with cystic fibrosis

BACKGROUND

Cystic fibrosis (CF) is characterized by altered exocrine secretions; however, no comprehensive compositional profile of CF serous and mucous saliva secretions has been published.

DESIGN

We analyzed salivary flow rate and composition, and oxidative stress-related parameters, comparing CF patients with non-CF bronchiectasis patients and the healthy controls.

RESULTS

Median salivary magnesium concentration and lactate dehydrogenase activity were significantly lower in CF patients than in the healthy controls. Salivary total protein concentration was 45% higher in CF patients than in non-CF bronchiectasis patients. CF patients showed 8% lower levels of peroxidase compared with non-CF bronchiectasis. Salivary total antioxidant status, superoxide dismutase and uric acid values in the CF group were higher by 15%, 35% and 31%, respectively, than in both control groups.

CONCLUSIONS

Cystic fibrosis patients demonstrated altered salivary profile, especially in antioxidant enzymatic and molecular activity, possibly resulting from the oral cavity's ongoing inflammatory and oxidative process. Free radical mechanisms may be involved in CF pathogenesis.

Serum and salivary oxidative analysis in Complex Regional Pain Syndrome

Although both inflammatory and neural mechanisms have been suggested as potential contributors to Complex Regional Pain Syndrome type I (CRPS-I), the pathogenesis of the syndrome is still unclear. Clinical trials have shown that free radical scavengers can reduce signs and symptoms of CRPS-I, indirectly suggesting that free radicals and increased oxidative stress are involved in the pathogenesis of CRPS-I. This study investigated this premise by determining the levels of antioxidants in the serum and saliva of 31 patients with CRPS-I and in a control group of 21 healthy volunteers. Serum lipid peroxidation products (MDA) and all antioxidative parameters analyzed were significantly elevated in CRPS-I patients: median salivary peroxidase and superoxide dismutase (SOD) activity values, uric acid (UA) concentration and total antioxidant status (TAS) values were higher in CRPS-I patients by 150% (p=0.01), 280% (p=0.04), 60% (p=0.0001), and 200% (p=0.0003), respectively, as compared with controls. Similar although not as extensive pattern of oxidative changes were found in the serum: mean serum UA and MDA concentrations and TAS value in the CRPS-I patients were higher by 16% (p=0.04), 25% (p=0.02), and 22% (p=0.05), respectively, than in the controls. Additionally, median salivary albumin concentration and median salivary LDH activities in the patients were 2.5 times (p=0.001) and 3.1 (p=0.004) times higher than in the controls. The accumulated data show that free radicals are involved in the pathophysiology of CRPS-I, which is reflected both in serum and salivary analyses. These data could be used for both diagnostic and therapeutic purposes in CRPS-I patients.

Salivary analysis and antioxidants in cleft lip and palate children

OBJECTIVE

To investigate the sialometry, sialochemistry and antioxidants in cleft patients prior to alveolar closure procedures.

DESIGN

Saliva was collected from 21 children with unilateral and bilateral cleft lip and palate (UCLP and BCLP) with overt oronasal alveolar communication and with recurrent licking of fluids and soft diet complaints (the study group) and in 22 normal individuals (the control group). Salivary flow rate was measured, and calcium (Ca), phosphate (P), magnesium (Mg), total protein, albumin, amylase, lactate dehydrogenase (LDH), and secretory IgA were analysed. Salivary total antioxidant status (TAS), peroxidase activity, superoxide dismutase (SOD) activity, uric acid (UA), was also determined.

RESULTS

The sialometry and sialochemistry analyses did not reveal significant difference between the two groups. Salivary median uric acid concentration was 6-fold lower in the cleft group (p<0.05). The median total antioxidant status (TAS) of the cleft group however, was significantly higher by 58% (p<0.005) than that of the control group. Median SOD activity was also higher in the cleft group, by 42%, though these differences did not reach statistical significance.

CONCLUSIONS

Our findings suggest that the oral biology system of cleft patients in their prealveolar closure stage does not differ significantly from normal controls. Low UA found in the saliva of cleft patients may suggest that some genetic alteration of the UA transport occurs simultaneously when cleft lip and palate occur. TAS reduction may also reveal an increased oxidative stress burden in the oral cavities of cleft children which has never been shown before.

Concomitant analysis of salivary tumor markers--a new diagnostic tool for oral cancer

PURPOSE

Oral squamous cell carcinoma (OSCC) is a common human malignancy. Circulatory epithelial tumor markers were previously investigated in the serum of OSCC patients but almost never in their saliva, in spite of the fact that there is a direct contact between the saliva and the oral cancer lesion. The purpose of the current study was to examine tumor markers in the saliva of OSCC patients.

EXPERIMENTAL DESIGN

We measured the concentrations of the six most studied epithelial serum circulatory tumor markers in the saliva of OSCC (tongue) patients.

RESULTS

Significant increases (of 400%) in salivary concentrations of Cyfra 21-1, tissue polypeptide antigen, and CA125 were shown. Salivary concentrations of CA19-9, SCC, and carcinoembryonic antigen were increased without statistical significance. A concurrent analysis of the three significantly increased markers revealed sensitivity, specificity, and negative and positive predictive values of 71%, 75%, 71%, and 75%, respectively.

CONCLUSIONS

The increase reported in salivary tumor markers may be used as a diagnostic tool, especially when a concurrent analysis for significantly increased markers is done. Salivary testing is noninvasive, making it an attractive, effective alternative to serum testing, and the possibility of developing home testing kits would further facilitate it as a diagnostic aid, enabling patients to monitor their own health at home and is important for those who live far from their treatment centers and especially for those at risk of developing OSCC.

Comparison of Electrokinetics-Based Multidimensional Separations Coupled with Electrospray Ionization-Tandem Mass Spectrometry for Characterization of Human Salivary Proteins

The foundation for saliva-based diagnostics is the development of a complete catalog of secreted proteins detectable in saliva. Besides protein complexity, the greatest bioanalytical challenge facing comprehensive analysis of saliva samples is related to the large variation of protein relative abundances including the presence of high-abundance proteins such as amylases, mucins, proline-rich proteins (PRPs), and secretory IgA complex. Among a number of electrokinetic separation techniques, transient capillary isotachophoresis/capillary zone electrophoresis (CITP/CZE) specifically targets trace amounts of proteins and thus reduces the range of relative protein abundances for providing unparallel advantages toward the identification of low-abundance proteins. By employing a CITP/CZE-based multidimensional separation platform coupled with electrospray ionization-tandem mass spectrometry (ESI-tandem MS), a total of 6112 fully tryptic peptides are sequenced at a 1% false discovery rate (FDR), leading to the identification of 1479 distinct human SwissProt protein entries. By comparing with capillary isoelectric focusing (CIEF) as another electrokinetics-based stacking approach, CITP/CZE not only offers a broad field of application but also is less prone to protein/peptide precipitation during the analysis. The ultrahigh resolving power of CITP/CZE is evidenced by the large number of distinct peptide identifications measured from each CITP fraction together with the low peptide fraction overlapping among identified peptides. Furthermore, when evaluating the protein sequence coverage by the number of distinct peptides mapping to each protein identification, the CITP-based proteome technology similarly achieves the superior performance with 674 proteins (46%) having three or more distinct peptides, 288 (19%) having two distinct peptides, and 517 (35%) having a single distinct peptide.

Salivary and gustatory alterations among bulimia nervosa patients

OBJECTIVE AND DESIGN

This study systematically examined salivary composition and taste perception and monitored related subjective complaints in a group of bulimia nervosa (BN) patients.

SUBJECTS

Fifty-two consenting female individuals participated in the current cross-sectional study, 26 patients diagnosed with BN according to the Diagnostic and Statistical Manual of Mental Disorders-IV (DSM-IV) criteria (mean age: 24+/-7 years) and 26 healthy controls matching in age and body mass index (BMI).

METHODS

All participants were given diagnostic BN-related questionnaires, had taste and salivary-composition analyses and were monitored for oral sensorial complaints. The patients were also subjected to psychological and psychiatric examinations focusing on established criteria known to be pathognomonic of the disease (including binge eating episodes, depression, impulsive traits, enhanced awareness of body image, typical compensatory behavior, and so on).

RESULTS

The self-answered questionnaires of Bulimic Investigatory Test Edinburgh (BITE), Beck Depression Inventory (BDI), brief symptom inventory (BSI) and impulsivity scale (IS) revealed highly significant differences between the two groups with respect to the various BN diagnostic symptoms of the patients (P=0.0001). Subjective and objective examinations showed an overall disturbed salivary and taste profile in BN patients, who complained of xerostomia (dry mouth) and taste aberration or oral burning sensation.

CONCLUSIONS

Regardless of the specific mechanism responsible for the disturbed salivary and taste profile in BN patients, these observed changes are associated with active illness. Accordingly, administration of therapeutic agents, including antioxidants, anti-inflammatory drugs and saliva substitutes, to the oral cavity (and maybe even systemically) of BN patients should be considered.

Age-related changes in salivary antioxidant profile: possible implications for oral cancer

Oral cancer's much higher prevalence among older people may be due to an age-related reduction in protective salivary antioxidant mechanisms and/or an age-related increase in the magnitude of oral carcinogen attack, such as reactive oxygen species (ROS) and reactive nitrogen species (RNS), causing DNA aberrations. This study found a significantly reduced total value of salivary antioxidant capacity in elderly persons (as measured by overall antioxidant capacity [ImAnOx] assay), (46% of healthy individuals, p =.004), increased oxidative stress (86% increase in carbonyl concentrations--indicators of enhanced ROS attack, p =.001), and increased salivary concentrations and total values of RNS (7-fold and 3-fold higher respectively, p =.001), all contributing to increased DNA oxidation of oral epithelial cells. Salivary oxidative stress-related changes in the intimately related saliva and oral epithelium compounded with higher viscosity of saliva may explain the higher prevalence of oral cancer in the elderly population. Administration of local therapeutic agents (i.e., antioxidants) to the oral cavity should be considered.

Relationship of flow rate, uric acid, peroxidase, and superoxide dismutase activity levels with complications in diabetic patients: can saliva be used to diagnose diabetes?

Can salivary free radicals and antioxidant parameters be useful in general diagnosis and evaluation of diabetes mellitus Type II (DM)? Serum and salivary redox state of 40 diabetes mellitus patients were examined and compared with 20 controls. The involvement of salivary gland in diabetes mellitus has been suggested based on salivary flow rate and compositional alterations. In addition, the redox state of saliva of diabetes mellitus patients is different than that of normoglycemic control human subjects. This observation unveils the opportunity to use noninvasive saliva-based diagnostics for diabetes mellitus patients.