Characterization of the unique oral microbiome of children harboring Helicobacter pylori in the oral cavity.

Objective: Helicobacter pylori infection is acquired in childhood via the oral cavity, although its relationship with the characteristics of the oral microbiome has not been elucidated. In this study, we performed comprehensive analysis of the oral microbiome in children and adults with or without H. pylori in the oral cavity. Methods: Bacterial DNA was extracted from 41 adult and 21 child saliva specimens, and H. pylori was detected using PCR. 16S rRNA gene amplification was performed for next-generation sequencing. Bioinformatic analyses were conducted using Quantitative Insights into Microbial Ecology 2 (QIIME 2). Results: Faith's phylogenetic diversity analysis showed a significant difference between H. pylori-negative adult and child specimens in terms of α-diversity (p < 0.05), while no significant difference was observed between H. pylori-positive adult and child specimens. There was also a significant difference in ß-diversity between H. pylori-positive and negative child specimens (p < 0.05). Taxonomic analysis at the genus level revealed that Porphyromonas was the only bacterium that was significantly more abundant in both H. pylori-positive adults and children than in corresponding negative specimens (p < 0.01 and p < 0.05, respectively). Conclusion: These results suggest unique oral microbiome characteristics in children with H. pylori infection in the oral cavity.

Host-microbiome associations in saliva predict COVID-19 severity.

Established evidence indicates that oral microbiota plays a crucial role in modulating host immune responses to viral infection. Following severe acute respiratory syndrome coronavirus 2, there are coordinated microbiome and inflammatory responses within the mucosal and systemic compartments that are unknown. The specific roles the oral microbiota and inflammatory cytokines play in the pathogenesis of coronavirus disease 2019 (COVID-19) are yet to be explored. Here, we evaluated the relationships between the salivary microbiome and host parameters in different groups of COVID-19 severity based on their oxygen requirement. Saliva and blood samples (n = 80) were collected from COVID-19 and from noninfected individuals. We characterized the oral microbiomes using 16S ribosomal RNA gene sequencing and evaluated saliva and serum cytokines and chemokines using multiplex analysis. Alpha diversity of the salivary microbial community was negatively associated with COVID-19 severity, while diversity increased with health. Integrated cytokine evaluations of saliva and serum showed that the oral host response was distinct from the systemic response. The hierarchical classification of COVID-19 status and respiratory severity using multiple modalities separately (i.e. microbiome, salivary cytokines, and systemic cytokines) and simultaneously (i.e. multimodal perturbation analyses) revealed that the microbiome perturbation analysis was the most informative for predicting COVID-19 status and severity, followed by the multimodal. Our findings suggest that oral microbiome and salivary cytokines may be predictive of COVID-19 status and severity, whereas atypical local mucosal immune suppression and systemic hyperinflammation provide new cues to understand the pathogenesis in immunologically compromised populations.

Potential salivary and serum biomarkers for burning mouth syndrome and their relationship with anxiety/depression.

Background/purpose: The pathophysiology of burning mouth syndrome (BMS), although considered a multifactorial etiology including psychological factors, is still not well understood. Hence, this study aimed to investigate the potential usage of salivary and serum biomarkers, including brain-derived neurotrophic factor (BDNF), interferon-gamma (IFN-γ), interleukin-1beta (IL-1ß), interleukin-6 (IL-6), interleukin-8 (IL-8), and tumor necrosis factor-alpha (TNF-α), in diagnosing BMS and their correlations with anxiety/depression. Materials and methods: 45 BMS patients and 14 healthy volunteers were enrolled. The patients were divided into BMS with anxiety/depression group and BMS without anxiety/depression group according to the scores of the Zung Self-rating Anxiety Scale (SAS) and Zung Self-rating Depression Scale (SDS). Additionally, concentrations of BDNF, IFN-γ, IL-1ß, IL-6, IL-8, and TNF-α in saliva and those in serum among the patients and healthy volunteers were assessed by multiplex assay using Luminex 200TM system and Enzyme-linked immunosorbent assay (ELISA), respectively. Results: Among all the serum biomarkers, only BDNF showed a statistically significant decrease in the patients than the healthy volunteers (P < 0.05). Regarding saliva biomarkers, BDNF, IL-1ß, and IL-8 all exhibited a statistically significant increase in all the BMS patients versus the healthy volunteers (P < 0.05) but only BDNF was significantly different between patients with anxiety/depression and healthy individuals when considering anxiety/depression. Among BMS patients with anxiety/depression, saliva TNF-α had positive associations with other biomarkers including BDNF, IFN-γ, IL-1ß, IL-6, and IL-8 (P < 0.05). Conclusion: The increased concentration of saliva BDNF holds strong potential for diagnosing BMS and the elevated level of saliva TNF-α is crucial in identifying BMS patients with anxiety/depression.

The Influence of Circadian Rhythm on the Antioxidant Capacity of Saliva in Periodontal Diseases.

Background Saliva has a powerful antioxidant activity proposing that it might have a protective role in the oral cavity. It is yet unclear, how circadian rhythm might affect this activity. Objective The main goal of this study was to compare the antioxidant status of saliva in patients with periodontal diseases (PD) to that of healthy people on a diurnal basis. Material and methods A total of 18 periodontal healthy individuals and 18 patients with chronic periodontitis were chosen. Samples of saliva were collected in the morning between 6:00 and 8:00 and in the evening between 6:00 and 8:00 (both stimulated and non-stimulated). The amount of glutathione (GSH), malondialdehyde (MDA), and total antioxidant status (TAS) in the salivary samples were analyzed, and its flow was also assessed. In addition, the scavenging capacity of saliva was tested in three systems generating oxygen free radicals. Results Results showed that GSH and TAS concentrations in the evening saliva of healthy subjects were significantly higher than those in the morning saliva, while MDA levels decreased (p<0.05). Conversely, there was no significant increase in GSH and TAS levels in the evening saliva of subjects with PD, and lipid peroxidation remained constant. On the other hand, the evening saliva of healthy subjects but not of subjects with PD was significantly more potent in scavenging free radicals in vitro than the morning saliva, especially for the superoxide (O2.-) radical (p<0.05). Moreover, scavenging activity was higher in stimulated than non-stimulated saliva. This activity was higher in evening saliva compared to the morning one and greater in healthy subjects compared to patients with PD (p<0.05). Conclusion A balance exists between oxidative stress and antioxidant mechanisms to maintain homeostasis in the oral cavity. This balance is deregulated in patients with PD as their saliva is unable to properly scavenge free radicals that might potentially increase over the day. Antioxidant supplements may be used in accordance with the circadian rhythm to minimize oxidative damage.

Clinical characteristics and salivary biomarkers of burning mouth syndrome.

OBJECTIVES: To investigate the clinical characteristics and salivary biomarkers in each type of burning mouth syndrome (BMS) patients. MATERIALS AND METHODS: Ninety-eight postmenopausal female patients with BMS were included. Fifty and 21 patients were assigned to the primary and secondary groups, respectively. Twenty-seven patients with both primary and secondary characteristics were assigned to the intermediate group. Comprehensive clinical characteristics and salivary biomarkers were analyzed. RESULTS: Significant differences in age, proportion of hyposalivator patients based on unstimulated whole saliva (UWS), symptom distribution, severties of burning sensation and effect of oral complaints in daily life (Eff-life), and positive symptom distress index (PSDI) were observed among the three groups. The primary group had significant higher UWS flow rate, fewer UWS hyposalivator proportions, and lesser severity of Eff-life than the secondary group. The intermediate group had significantly greater intensities of burning sensation and Eff-life and higher PSDI score than did the primary group. The primary group had significantly higher cortisol and dehydroepiandrosterone (DHEA) levels in stimulated whole saliva than did the secondary group. CONCLUSIONS: This study's findings show that clinical characteristics differentiate each BMS type. Cortisol and DHEA levels are potential salivary biomarkers for discriminating between the primary and secondary types of BMS.

Salivary Neutrophil-to-Lymphocyte Ratio as a Prognostic Predictor of Oral Premalignant and Malignant Disorders: A Prospective Study.

INTRODUCTION: Inflammation is a definitive characteristic of carcinogenesis. The neutrophil-to-lymphocyte ratio (NLR) is an easy and efficient indicator of inflammation and a valuable marker in individuals with malignancies. The present study was performed to ascertain NLR values in salivary samples collected from individuals with oral premalignant disorders (OPMDs) and to assess the prognostic significance of NLR in distinguishing OPMDs from oral malignancies. MATERIALS AND METHODS: This study was conducted on 50 patients histopathologically diagnosed with OPMDs with mild dysplasia. The patients were provided with standard medicinal treatment, encouraged to quit their habits, and followed up for one year at three-month regular intervals. During the follow-up, 29 (67.4%) patients completely recovered, whereas 14 (32.6%) developed oral malignancies. Salivary samples were collected at baseline (T0) and one-year follow-up (T1). The total salivary neutrophils and lymphocytes were counted using an improved cell counting method with a Neubauer chamber. The NLR values were calculated at T0 and T1. The paired t-test was used to compare the NLR values at T0 and T1. The cutoff value of the NLR was determined using the receiver operating characteristic (ROC) curve. The Youden index was used to determine the optimal cutoff NLR values in the groups. Statistical significance was set at p ≤0.05. RESULTS: OPMDs were predominantly observed in males, with leukoplakia being the most prevailing one. Erythroplakia exhibited the highest propensity for malignant transformation, and habitual consumption of alcohol and tobacco was identified as a risk factor for this transformation. NLR increased in both premalignant and malignant conditions. NLR value equal to or exceeding 4 was determined to be a reliable indicator for the occurrence of oral cancer in patients with OPMDs. The ROC curve analysis yielded a sensitivity and specificity of 92%, with an area under the curve (AUC) of 0.928. CONCLUSION: The poor prognosis of oral cancers was associated with higher NLR values. NLR values in salivary samples can serve as an independent reliable predictor in oral cancer and OPMDs.

Influence of saliva on the sensory properties of US commercial smoke affected wines: Preliminary findings.

Previous research has suggested that the impact of smoke affected wines require human evaluation due to in-mouth changes in perception, perhaps associated with saliva. Smoke affected wines (n = 36) from three major wine growing regions in the US were sourced from commercial wineries. A subset of these wines (n = 7) were evaluated by a consumer panel (n = 57) and electronic tongue (e-tongue) to determine the influence of saliva in the sensory profile. Consumers assessed the wines for aroma and other sensory attributes, before and after individual saliva addition. Pooled saliva from consumers was used to treat all wines obtained (n = 36) and then analyzed using the e-tongue. Results showed that saliva did not significantly alter the overall aroma, other than fruity or woody aroma liking by consumers (p > .05). However, the presence of saliva significantly lowered overall liking in both red and white wines that were affected by smoke (p ≤ .05). Consumers rated the subset of smoke affected wines below the "might purchase" category, indicating these wines were not considered acceptable by consumers. When individual pairs of smoke affected wines (before and after saliva additions) were assessed using the e-tongue, the device was able to differentiate the pairs, validating potential usefulness to discern wine changes, though the discrimination indices were moderate to low (68.8% to 11.9%). Based on these data, in human ratings of the aroma and appearance of smoked affected wines, saliva decreased overall liking, and this was somewhat distinguishable by e-tongue analysis.

Gender Identification by Fingerprint Pattern and Salivary Blood Group Antigen Expression: A Forensic Approach.

Introduction Fingerprints found at the crime scene are important and valuable evidence, as they are unique to every individual. Determining the blood group from the blood samples obtained at the site of the crime helps in identifying a person. However, where blood stains are not available, saliva obtained at the crime site can be used to identify the victim. Since fingerprint patterns and blood groups are unique to every individual and remain unchanged throughout life, the correlation between dermatoglyphics and blood groups can be of use in victim identification. Objectives The present study is conducted with the objective of finding out if there is any association between the distribution of fingerprint patterns and blood groups and if this association is of use in gender identification. Materials and method Fingerprint patterns were determined in 200 (females: n = 152, males: n = 48) dental undergraduate students in the age range of 18 to 24 years. ABO blood grouping was done on saliva by using the absorption-elution method. To determine the accuracy of ABO blood group determination using saliva, it was correlated with the ABO blood grouping in blood.  Observations and result The most common fingerprint pattern was found to be loops (87, 43.50%), followed by whorls (81, 40.50%) and arches (32, 16.00%). The most common blood group was B (68, 34%), followed by O (46, 23%) and A (42, 21%), and the least common was AB (12, 6%). A higher percentage of secretors in saliva was observed in females (130, 86%) than males (38, 79%). The correlation of gender with blood group and fingerprint pattern showed that in males, the most common blood group was B (20, 42%), and the most common fingerprint pattern was whorls (21, 44%). In females, the most common blood group was B (48, 32%), while the most common fingerprint pattern was loop (68, 45%). Conclusion Present study reports an association between blood group and dermatoglyphics, which may help in gender identification. Saliva can be used as a helpful tool in victim identification in cases where blood stains are not available.

MOLECULAR DETECTION PROTOCOL OF SARS-COV-2 THROUGH SELF-COLLECTED SALIVA SPECIMENS VERSUS NASOPHARYNGEAL SWABS.

Background: Several reports have shown that saliva specimen is an excellent alternative biofluid sample for SARS-CoV-2 detection. We conducted this study, in order to assess the sensitivity and specificity of using saliva self-collected by adult and pediatric patients, as a biological sample for RT-PCR diagnosis. Aims: The present study was carried out to assess the sensitivity and specificity of using saliva self-collected from adult and pediatric patients, as a biological sample for RT-qPCR diagnosis. Methods: In this study, 50 symptomatic patients and 40 asymptomatic subjects (adult and pediatric) were enrolled between September 2020 and November 2020 at the Department of Infectious Diseases, Bejaia University Hospital (CHU), and tested simultaneously for the sensitivity and specificity of the SARS-CoV-2 viral genome by RT-PCR on both nasopharyngeal swabs NP swab and saliva samples. Results: Our RT-qPCR results revealed that saliva samples showed the highest sensitivity (95% CI [27.67, 29.82]) followed by a nasopharyngeal swab for symptomatic (95% CI [29.64, 31.49]) as well as for asymptomatic adult patients. Moreover, the saliva of symptomatic and asymptomatic patients was monitored, and the presence of viral RNA was detected in >95% of the asymptomatic patients as well as the symptomatic patients. Surprisingly, the Ct values of ORF1ab and N genes are highly lower in nasopharyngeal swabs compared to saliva. Indeed, the mean difference note that for the ORF1ab gene and N gene, the mean of difference in ΔCt value were respectively 3.683 and 3.578. Together, including symptomatic and asymptomatic subjects, the overall agreement between the saliva sample and the nasopharyngeal is about 84%. Conclusion: The sensitivity of saliva samples remains acceptable; it may still be a viable option in locations where laboratory facilities are lacking for diagnostic purposes in the early phase of the disease.

Diagnostic performance, stability, and acceptability of self-collected saliva without additives for SARS-CoV-2 molecular diagnosis.

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) caused the coronavirus disease 2019 (COVID-19), leading to a global pandemic. The molecular diagnosis of this virus is mostly performed by collecting upper respiratory samples, which has many disadvantages, including patient discomfort and the need for trained healthcare professionals. Although saliva has emerged as a more comfortable sample, the use of additives to preserve viral RNA is expensive and, in some cases, difficult for self-collection. METHOD: This study evaluated the diagnostic performance by RT-PCR and stability of self-collected saliva using wide-mouth specimen collection cups without stabilization and/or inactivation buffers for SARS-CoV-2 detection, compared to nasopharyngeal samples and saliva collected with additives. Additionally, the study assessed the acceptability of this sample collection method among participants and healthcare personnel. RESULTS: The study included 1281 volunteers with a 24.6% positive infection rate. Saliva demonstrated comparable diagnostic performance to nasopharyngeal samples, with a sensitivity of 87.6% and specificity of 99.6%, for a total percent agreement of 96.4%. The study also showed that viral RNA in saliva remained stable for at least 72 h at different temperatures. Notably, saliva samples without additives exhibited a lower RdRp Ct compared to samples with additives, suggesting that the absence of stabilization and/or inactivation buffers does not significantly affect its performance. The study highlighted the acceptability of saliva among patients and healthcare personnel due to its noninvasive nature and ease of collection. CONCLUSIONS: This research supports the implementation of self-collected saliva as a comfortable and user-friendly alternative sample for SARS-CoV-2 diagnosis.

Proteomic Analysis of Salivary Extracellular Vesicles from COVID-19 Patients Reveals a Specific Anti-COVID-19 Response Protein Signature.

Despite the understanding of the coronavirus disease-19 (COVID-19), the role of salivary extracellular vesicles (sEVs) in COVID-19 remains unclear. Exploring the proteomic cargo of sEVs could prove valuable for diagnostic and prognostic purposes in assessing COVID-19. The proteomic cargo of sEVs from COVID-19(+) subjects and their healthy close contacts (HCC) was explored. sEVs were isolated by ultracentrifugation from unstimulated saliva samples, and subsequently characterized through nanoparticle tracking, transmission electron microscopy, and Western blot analyses. The proteomic cargo of sEVs was processed by LC-MS/MS. sEVs were morphologically compatible with EVs, with the presence of Syntenin-1 and CD81 EV markers. The sEV pellet showed 1417 proteins: 1288 in COVID-19(+) cases and 1382 in HCC. In total, 124 proteins were differentially expressed in sEVs from COVID-19(+) subjects. "Coronavirus-disease response", "complement and coagulation cascades", and "PMN extracellular trap formation" were the most enriched KEGG pathways in COVID-19(+) cases. The most represented biological processes were "Hemoglobin and haptoglobin binding" and "oxygen carrier activity", and the best-denoted molecular functions were "regulated exocytosis and secretion" and "leucocyte and PMN mediated immunity". sEV proteomic cargo in COVID-19(+) suggests activity related to immune response processes, oxygen transport, and antioxidant mechanisms. In contrast, in HCC, sEV signature profiles are mainly associated with epithelial homeostasis.

Appearance of hexahydrocannabinols as recreational drugs and implications for cannabis drug testing - focus on HHC, HHC-P, HHC-O and HHC-H.

This study investigated the effects of hexahydrocannabinol (HHC) and other unclassified cannabinoids, which were recently introduced to the recreational drug market, on cannabis drug testing in urine and oral fluid samples. After the appearance of HHC in Sweden in 2022, the number of posts about HHC on an online drug discussion forum increased significantly in the spring of 2023, indicating increased interest and use. In parallel, the frequency of false positive screening tests for tetrahydrocannabinol (THC) in oral fluid, and for its carboxy metabolite (THC-COOH) in urine, rose from <2% to >10%. This suggested that HHC cross-reacted with the antibodies in the immunoassay screening, which was confirmed in spiking experiments with HHC, HHC-COOH, HHC acetate (HHC-O), hexahydrocannabihexol (HHC-H), hexahydrocannabiphorol (HHC-P), and THC-P. When HHC and HHC-P were classified as narcotics in Sweden on 11 July 2023, they disappeared from the online and street shops market and were replaced by other unregulated variants (e.g. HHC-O and THC-P). In urine samples submitted for routine cannabis drug testing, HHC-COOH concentrations up to 205 (mean 60, median 27) µg/L were observed. To conclude, cannabis drug testing cannot rely on results from immunoassay screening, as it cannot distinguish between different tetra- and hexahydrocannabinols, some being classified but others unregulated. The current trend for increased use of unregulated cannabinols will likely increase the proportion of positive cannabis screening results that need to be confirmed with mass spectrometric methods. However, the observed cross-reactivity also means a way to pick up use of new cannabinoids that otherwise risk going undetected.

Shaping the future of oral cancer diagnosis: advances in salivary proteomics.

INTRODUCTION: Saliva has gained increasing attention in the quest for disease biomarkers. Because it is a biological fluid that can be collected is an easy, painless, and safe way, it has been increasingly studied for the identification of oral cancer biomarkers. This is particularly important because oral cancer is often diagnosed at late stages with a poor prognosis. AREAS COVERED: The review addresses the evolution of the experimental approaches used in salivary proteomics studies of oral cancer over the years and outlines advantages and pitfalls related to each one. In addition, examines the current landscape of oral cancer biomarker discovery and translation focusing on salivary proteomic studies. This discussion is based on an extensive literature search (PubMed, Scopus and Google Scholar). EXPERT OPINION: The introduction of mass spectrometry has revolutionized the study of salivary proteomics. In the future, the focus will be on refining existing methods and introducing powerful experimental techniques such as mass spectrometry with selected reaction monitoring, which, despite their effectiveness, are still underutilized due to their high cost. In addition, conducting studies with larger cohorts and establishing standardized protocols for salivary proteomics are key challenges that need to be addressed in the coming years.

Investigating the metabolite signature of an altered oral microbiota as a discriminant factor for multiple sclerosis: a pilot study.

In multiple sclerosis (MS), alterations of the gut microbiota lead to inflammation. However, the role of other microbiomes in the body in MS has not been fully elucidated. In a pilot case-controlled study, we carried out simultaneous characterization of faecal and oral microbiota and conducted an in-depth analysis of bacterial alterations associated with MS. Using 16S rRNA sequencing and metabolic inference tools, we compared the oral/faecal microbiota and bacterial metabolism pathways in French MS patients (n = 14) and healthy volunteers (HV, n = 21). A classification model based on metabolite flux balance was established and validated in an independent German cohort (MS n = 12, HV n = 38). Our analysis revealed decreases in diversity indices and oral/faecal compartmentalization, the depletion of commensal bacteria (Aggregatibacter and Streptococcus in saliva and Coprobacter and Roseburia in faeces) and enrichment of inflammation-associated bacteria in MS patients (Leptotrichia and Fusobacterium in saliva and Enterobacteriaceae and Actinomyces in faeces). Several microbial pathways were also altered (the polyamine pathway and remodelling of bacterial surface antigens and energetic metabolism) while flux balance analysis revealed associated alterations in metabolite production in MS (nitrogen and nucleoside). Based on this analysis, we identified a specific oral metabolite signature in MS patients, that could discriminate MS patients from HV and rheumatoid arthritis patients. This signature allowed us to create and validate a discrimination model on an independent cohort, which reached a specificity of 92%. Overall, the oral and faecal microbiomes were altered in MS patients. This pilot study highlights the need to study the oral microbiota and oral health implications in patients with autoimmune diseases on a larger scale and suggests that knowledge of the salivary microbiome could help guide the identification of new pathogenic mechanisms associated with the microbiota in MS patients.

Diurnal 11-ketotestosterone and 17-hydroxyprogesterone saliva profiles in paediatric classical congenital adrenal hyperplasia.

OBJECTIVES: The most suitable biochemical markers for therapy adjustment in patients with congenital adrenal hyperplasia are controversial. 11-Oxygenated androgens are a promising new approach. The objective of this study was to investigate the diurnal rhythm of 11-ketotestosterone in children and adolescents in saliva and to correlate it with salivary 17-hydroxyprogesterone. METHODS: Fifty-one samples of steroid day-profiles from 17 patients were additionally analysed for 11-ketotestosterone, retrospectively. All patients were treated in our university outpatient clinic for paediatric endocrinology between 2020 and 2022. Steroid day-profiles of 17 patients could be examined. The cohort showed a balanced sex ratio. The median age was 13 years. The measurements for 17-hydroxyprogesterone were carried out during routine care by immunoassay. The measurements of 11-ketotestosterone were performed from frozen saliva samples using an implemented in-house protocol for liquid chromatography - tandem mass spectrometry (LC-MS/MS). The most important outcome were the absolute values for 11-ketotestosterone, their diurnal rhythmicity and the correlation with 17-hydroxyprogesterone. RESULTS: Both steroids show a circadian diurnal rhythm. 17-hydroxyprogesterone and 11-ketotestosterone correlate significantly. 11-Ketotestosterone showed a positive correlation with BMI at all times of the day. CONCLUSIONS: 11-Ketotestosterone shows circadian rhythmicity in our cohort and correlates with 17-hydroxyprogesterone. These findings serve as an important basis for prospective research into 11-oxygenated androgens as therapeutic markers in paediatrics. However, 11-ketotestosterone appears to be very dependent on BMI.

Saliva and tongue microbiota in burning mouth syndrome: An exploratory study of potential roles.

OBJECTIVES: Burning mouth syndrome (BMS) is a chronic orofacial pain disorder with unclear etiology, in which the tongue is most commonly affected. This study aims to provide implication of the possible relationship between oral microbiota and the pathogenesis of BMS. MATERIALS AND METHODS: Saliva and tongue swabs of 15 primary BMS patients and 10 healthy controls were collected and assessed by 16S rRNA gene amplicon sequencing. The microbiota compositions were compared and bioinformatic analysis was conducted. RESULTS: Differences in microbiota compositions between BMS patients and healthy controls were revealed in both saliva and tongue samples. In saliva, Streptococcus, Rothia, and Neisseria were the predominant genus at the taxonomic level in BMS patients. In tongue samples, Prevotella, Streptococcus, and Neisseria were the dominant genus at the taxonomic level in BMS patients. LEfSe analysis and linear discriminant analysis score showed that Actinobacteria were the predominant phylum in saliva, and Selenomonas were enriched in the dorsum of the tongue of BMS patients. CONCLUSIONS: This study for the first-time reported saliva and tongue microbiota profiles were distinguished from that of healthy controls, indicating a necessity for further research on the possible relationship between oral microbes and the pathogenesis of BMS.

A look upon the adsorption of different astringent agents to oral models: Understanding the contribution of alternative mechanisms in astringency.

Salivary proteins precipitation by interaction with polyphenols is the major mechanism for astringency. However, alternative mechanisms seem involved in the perception of different subqualities of astringency. In this study, adsorption of four astringent agents to in vitro oral models and their sensory properties were assessed. Overall, green tea infusion and tannic acid have shown a higher adsorption potential for models with oral cells and absence of saliva. Alum and grape seed extract presented higher adsorption in models with presence of oral cells and saliva. Multiple factor analysis suggested that adsorption may represent important mechanisms to elicit the astringency of alum. Models including saliva, were closely associated with overall astringency and aggressive subquality. Models with cells and absent saliva were closely associated with greenness, suggesting a taste receptor mechanism involvement in the perception. For the first time a correlation between an oral-cell based assay and astringency sensory perception was shown.

Estimation and Association of Total Protein Concentration with Early Childhood Caries in 3-6-year-old Children: A Randomized Clinical Trial.

Background and objective: Caries is a common problem witnessed in children, early childhood caries (ECC) is the most predominant chronic disease which not only leads to distress and pain but also poor quality of life, thus affecting the overall well-being of children. Salivary protein plays a vital part in monitoring health status or disease. It was stated that the salivary proteins could regulate the equilibrium of oral health, preserve a stable ecosystem, and constrain the growth of cariogenic bacteria. Aim: The aim of this study is to estimate the total protein concentration in saliva and its correlation to ECC. Materials and methods: A total of 20 patients with ECC in the age-group of 3-6 years were selected as the experimental group and 20 patients without caries for the control group. Unstimulated saliva samples were collected and subjected to spectrophotometry. The data obtained was subjected to statistical analysis. Independent student's t-test was used for the comparison of mean salivary pH between the caries group and the control group. Mann-Whitney test was used for a comparison of salivary total protein concentrations between the two groups. Results: The mean pH of the carious group showed a statistically significant slightly lower value than that of the noncarious group. On the contrary, the mean total protein concentration of the carious group presented a statistically significant higher value than that of the noncarious group. Age-wise comparison of mean salivary proteins in the carious group and the noncarious group showed an increase in the protein concentration in the children aged 4 years or younger. Conclusion: Based on the results of this study, it can be concluded that there is a strong association between the total protein concentration in saliva and ECC. There exists a significant increase in the total protein concentration in children with ECC. As age increases, total protein concentration decreases with age. Clinical significance: Total protein concentration and particular protein estimation and quantification help us in assessing the risk of caries in children at the earliest and prevention of caries through preventive measures. Estimation of total salivary protein concentration in children can be a marker for ECC in children. How to cite this article: Thimmegowda U, Pai S, Chikkanarasaiah N, et al. Estimation and Association of Total Protein Concentration with Early Childhood Caries in 3-6-year-old Children: A Randomized Clinical Trial. Int J Clin Pediatr Dent 2024;17(1):36-40.

Interactions between Salivary Proteins and Apple Polyphenols and the Fate of Complexes during Gastric Digestion.

Beneficial polyphenols in apples can reach the stomach as complexes formed with salivary proteins. The present study aimed at documenting the interactions between salivary proteins and cider apple polyphenols and the fate of complexes during gastric digestion. A polyphenolic extract was mixed with human saliva, and interactions were characterized by analyzing proteins and polyphenols in the insoluble and soluble fractions of the mixtures, before and after in vitro gastric digestion. Results confirmed that proline-rich proteins can efficiently precipitate polyphenols and suggested that two zinc-binding proteins can also form insoluble complexes with polyphenols. The classes of polyphenols involved in such complexes depended on the polyphenol-to-protein ratio. In vitro gastric digestion led to extensive proteolysis of salivary proteins, and we formulate the hypothesis that the resulting peptides can interact with and precipitate some procyanidins. Saliva may therefore partly modulate the bioaccessibility of at least procyanidins in the gastric compartment.

Antigen-functionalized turnip mosaic virus nanoparticles increase antibody sensing in saliva. A case study with SARS-CoV-2 RBD.

Nanoparticles derived from plant viruses play an important role in nanomedicine due to their biocompatibility, self-assembly and easily-modifiable surface. In this study, we developed a novel platform for increasing antibody sensing using viral nanoparticles derived from turnip mosaic virus (TuMV) functionalized with SARS-CoV-2 receptor binding domain (RBD) through three different methods: chemical conjugation, gene fusion and the SpyTag/SpyCatcher technology. Even though gene fusion turned out to be unsuccessful, the other two constructs were proven to significantly increase antibody sensing when tested with saliva of patients with different infection and vaccination status to SARS-CoV-2. Our findings show the high potential of TuMV nanoparticles in the fields of diagnostics and immunodetection, being especially attractive for the development of novel antibody sensing devices.