Altered coordination between sleep timing and cortisol profiles in night working female hospital employees.

BACKGROUND: Cortisol typically peaks in the morning after waking up and declines throughout the day, reaching its lowest levels during nighttime sleep. Shift work can cause misalignment between cortisol levels and sleep-wake timing. We analyzed this misalignment in female shift workers focusing on the timing and extent of these changes. METHODS: We conducted a cross-sectional study involving 68 shift workers (aged 37 ± 10 years) and 21 non-shift workers (aged 45 ± 10 years) from a hospital. Shift workers were monitored through two day shifts and three night shifts, whereas non-shift workers were monitored during two day shifts. Each participant collected six to eight saliva samples (depending on their shift type) and provided sleep timing information, which was recorded via polysomnography and sleep diaries. Generalized additive mixed models were used to estimate shift-specific differences in cortisol smooth curves. Summary measures calculated for the cortisol smooth curves included cortisol awakening response, peak-to-bed slope, and total output. RESULTS: Between shift workers and non-shift workers, we observed similar diurnal cortisol profiles with a steep negative diurnal slope during day shifts. In shift workers on night shifts, a flattened U-shaped cortisol profile after the post-awakening maximum was observed, with a peak-to-bed slope close to zero. When comparing night to day shifts in the group of shift workers, mean cortisol levels were lower between 42 and 56 minutes and 1.8-11.9 hours after waking up, and higher between 14.9 and 22 hours after waking up. CONCLUSION: Our findings indicate altered cortisol profiles in female hospital employees on night shifts. Specifically, cortisol levels were lower at night when higher levels would typically be necessary for work activities, and higher at bedtime after a night shift, when levels should normally be low.

Pediatric Salivary Gland Pathology.

Benign and malignant salivary gland disorders are uncommon in the pediatric population; however, these can be frequently seen in pediatric otolaryngology or oral and maxillofacial surgery practices. The astute clinician should be aware of the clinical presentation, diagnosis, and management options for common inflammatory, infectious, benign, and malignant disorders of salivary glands.

Oral microbiota of patients with phenylketonuria: A nation-based cross-sectional study.

AIM: The oral microenvironment contributes to microbial composition and immune equilibrium. It is considered to be influenced by dietary habits. Phenylketonuria (PKU) patients, who follow a lifelong low-protein diet, exhibit higher prevalence of oral diseases such as periodontitis, offering a suitable model to explore the interplay between diet, oral microbiota and oral health. MATERIALS AND METHODS: We conducted 16S rDNA sequencing on saliva and subgingival plaque from 109 PKU patients (ages 6-68 years) and 114 age-matched controls and correlated oral microbial composition and dental health. RESULTS: PKU patients exhibited worse dental health, reduced oral microbial diversity and a difference in the abundance of specific taxa, especially Actinobacteriota species, compared to controls. PKU patients with poor periodontal health exhibited higher alpha diversity than the orally healthy ones, marked by high abundance of the genus Tannerella. Notably, the observed taxonomic differences in PKU patients with normal indices of decayed/missing/filled teeth, plaque control record, gingival bleeding index and periodontal screening and recording index generally differed from microbial signatures of periodontitis. CONCLUSIONS: PKU patients' reduced microbial diversity may be due to their diet's metabolic challenges disrupting microbial and immune balance, thus increasing oral inflammation. Higher alpha diversity in PKU patients with oral inflammation is likely related to expanded microbial niches.

Metabolomics reveals early pregnancy biomarkers in sows: a non-invasive diagnostic approach.

In an effort to enhance reproductive management and reduce non-productive periods in swine breeding, this study presents a novel, non-invasive metabolomics approach for the identification of early pregnancy biomarkers in sows. Utilizing an untargeted metabolomics approach with mass spectrometry analysis, we examined saliva samples from pregnant (n = 6) and non-pregnant control sows (n = 6, artificially inseminated with non-viable sperm). Our analysis revealed 286 differentially expressed metabolites, with 152 being up-regulated and 134 down-regulated in the pregnant group. Among these, three metabolites, namely Hyodeoxycholic acid, 2'-deoxyguanosine, and Thymidine, emerged as potential early pregnancy biomarkers. These biomarkers were further evaluated using targeted LC-MS/MS quantification and qualification, accompanied by ROC curve analysis. The study confirmed Hyodeoxycholic acid and 2'-deoxyguanosine as promising biomarkers for early pregnancy detection, offering potential for future implementation in swine production environments. This research establishes a robust theoretical foundation for the development of innovative molecular diagnostic techniques and explores new avenues for molecular genetic breeding and non-invasive diagnostics, ultimately enhancing fertility and productivity in sow herds.

Salivary biomarkers: The early diagnosis of Alzheimer's disease.

The precise identification of Alzheimer's disease and other prevalent neurodegenerative diseases remains a difficult issue that requires the development of early detection of the disease and inexpensive biomarkers that can replace the present cerebrospinal fluid and imaging biomarkers. Blood biomarkers, such as amyloid and neurofilament light, have been emphasized as an important and practical tool in a testing or examination procedure thanks to advancements in ultra-sensitive detection techniques. Although saliva is not currently being researched for neurodegenerative diseases, it is an important source of biomarkers that can be used for the identification of diseases and has some advantages over other biofluids. While this may be true for most people, getting saliva from elderly people presents some significant challenges. In this overview, we will first discuss how saliva is created and how aging-related illnesses may affect the amount and kind of saliva produced. The findings support the use of salivary amyloid protein, tau species, and novel biomarkers in the diagnosis of Alzheimer's disease.

Influence of Obstructive Sleep Apnea on the Risk of Dental Caries: Insights from a 13-Year Population-Based Retrospective Study.

KNOWLEDGE TRANSFER STATEMENT: Obstructive sleep apnea has been proven to have a great negative impact on patients, and the relationship between sleep apnea and dental caries is still inconclusive. Our study shows that patients with sleep apnea and those older than 45 y have a significant risk of dental caries.

Concentration of Fluoride in Saliva After Fluoride Gel Application: A Randomised Clinical Trial.

OBJECTIVE: The aim of this randomised clinical trial (RCT) was to assess the concentration of fluoride ions in saliva after applying fluoride gel and to examine the extent to which rinsing the mouth with water affects the content of fluoride ions in saliva as opposed to no rinsing after brushing teeth with gel. METHODS: This single-blind RCT was conducted amongst a group of students (N = 103) and consisted of a questionnaire, clinical examination, saliva collection, and laboratory analysis. After saliva samples were collected, the students brushed their teeth for 2 minutes with Elmex Gelée (Colgate-Palmolive). Next, saliva was collected after 15 and 60 minutes from Group A (spitting out saliva after brushing) and from Group B (spitting out and rinsing with water after brushing). Statistical analysis was performed using a t test to compare the means between the groups. RESULTS: Fifteen minutes after brushing, the level of fluoride increased in Group A about 15-fold to 15.33 ± 14.73 ppm and in Group B about 6-fold to 6.19 ± 5.97 ppm (P < .001). After 60 minutes, in Group A it decreased to 1.68 ± 0.83 ppm and in Group B to 0.60 ± 0.37 ppm (P < .001). CONCLUSIONS: The use of fluoride gel in the absence of mouth rinsing produced significantly higher level and a concentration of fluoride in saliva. A post-gel brushing without rinsing might be suitable for patients at high risk for caries. Hence fruther research on the effect of a mouth rinse after use of fluoride gels is eesential to confirm our findings, and to promulgate evidence-based recommendations.

Salivary High-Sensitivity C-Reactive Protein and Its Clinical Relevance in Modern Medicine: A Comprehensive Review.

High-sensitivity C-reactive protein (hsCRP) has emerged as a critical biomarker in inflammation, offering insights into various chronic diseases. However, traditional blood-based assays for hsCRP measurement pose limitations regarding invasiveness and cost. In recent years, saliva has garnered attention as an alternative diagnostic medium, presenting a noninvasive and easily accessible option for biomarker analysis. Salivary hsCRP has thus emerged as a promising avenue for research and clinical application, offering potential advantages over blood-based assays. This comprehensive review aims to elucidate the biological basis of salivary hsCRP, its clinical applications, and methodologies for measurement. By exploring its diagnostic potential, prognostic value, and implications for treatment monitoring, this review highlights the potential impact of salivary hsCRP in modern medicine. Moreover, it emphasizes the need for continued exploration, validation, and integration of salivary hsCRP into routine clinical practice to realize its full potential for enhancing patient care and advancing personalized medicine approaches.

On the rheological and sensory properties of a novel natural salivary substitute.

The prevalence of xerostomia, the sensation of dry mouth, is estimated at 20% in the general population and up to 50% in older adults. Saliva plays different roles during bolus formation: lubrication, mixing, coating, hydration, dissolution, and comminution of food particles. This study proposes and tests artificial saliva formulations mimicking human saliva rheological and sensory perceptions. Shear and extensional rheology were assessed to select the type of formulation closest to saliva rheological characteristics. After evaluating three alternative sources, an extract simulating saliva rheology was produced from flax seeds. Friction coefficient and rheological properties, such as flow curves, relaxation times, and Trouton ratios, were compared favorably with human saliva. The sensory evaluation demonstrated that flaxseed extracts induce perceived mouth hydration, slipperiness, and adhesion exceeding that of human saliva. The flaxseed extract proposed in this can i) be used to study in vitro food oral processing and ii) pave the way to novel natural salivary substitutes to alleviate the symptoms of xerostomia.

Exogenous melatonin's effect on salivary cortisol and amylase: A randomized controlled trial.

This study aimed to examine the effect of acute exogenous melatonin administration on salivary cortisol and alpha-amylase (sCort and sAA) as representatives of the HPA axis and the sympathetic nervous system, respectively. A single-dose prolonged-release melatonin (2 mg) or a placebo tablet was given to healthy volunteers (n = 64) at 20:00 h in a crossover design. The saliva was collected at six time points (20:00, 21:00, awakening, 30 min after awakening, 10:00, and 12:00 h) and was measured for sCort, sAA, and salivary melatonin (sMT) levels. Pulse rates and sleep parameters were also collected. Melatonin was effective in improving sleep onset latency by 7:04 min (p = .037) and increasing total sleep time by 24 min (p = .006). Participants with poor baseline sleep quality responded more strongly to melatonin than participants with normal baseline sleep quality as they reported more satisfaction in having adequate sleep (p = .017). Melatonin administration resulted in higher sCort levels at awakening time point (p = .023) and a tendency of lower sAA levels but these were not significant. Melatonin ingestion at 20:00 h resulted in a marked increase in sMT levels at 21:00 h and remained higher than baseline up to at least 10:00 h (p < .001). Melatonin increases sCort levels at certain time point with a tendency to lower sAA levels. These opposing effects of melatonin suggested a complex interplay between melatonin and these biomarkers. Also, the results confirmed the positive acute effect of a single-dose melatonin on sleep quality.

Drinking water sources, quality, and associated health outcomes in Appalachian Virginia: A risk characterization study in two counties.

OBJECTIVES: In the US, violations of drinking water regulations are highest in lower-income rural areas overall, and particularly in Central Appalachia. However, data on drinking water use, quality, and associated health outcomes in rural Appalachia are limited. We sought to assess public and private drinking water sources and associated risk factors for waterborne pathogen exposures for individuals living in rural regions of Appalachian Virginia. METHODS: We administered surveys and collected tap water, bottled water, and saliva samples in lower-income households in two adjacent rural counties in southwest Virginia (bordering Kentucky and Tennessee). Water samples were tested for pH, temperature, conductivity, total coliforms, E. coli, free chlorine, nitrate, fluoride, heavy metals, and specific pathogen targets. Saliva samples were analyzed for antibody responses to potentially waterborne infections. We also shared water analysis results with households. RESULTS: We enrolled 33 households (83 individuals), 82% (n = 27) with utility-supplied water and 18% with private wells (n = 3) or springs (n = 3). 58% (n = 19) reported household incomes of <$20,000/year. Total coliforms were detected in water samples from 33% (n = 11) of homes, E. coli in 12%, all with wells or springs (n = 4), and Aeromonas, Campylobacter, and Enterobacter in 9%, all spring water (n = 3). Diarrhea was reported for 10% of individuals (n = 8), but was not associated with E. coli detection. 34% (n = 15) of saliva samples had detectable antibody responses for Cryptosporidium spp., C. jejuni, and Hepatitis E. After controlling for covariates and clustering, individuals in households with septic systems and straight pipes had significantly higher likelihoods of antibody detection (risk ratios = 3.28, 95%CI = 1.01-10.65). CONCLUSIONS: To our knowledge, this is the first study to collect and analyze drinking water samples, saliva samples, and reported health outcome data from low-income households in Central Appalachia. Our findings indicate that utility-supplied water in this region was generally safe, and individuals in low-income households without utility-supplied water or sewerage have higher exposures to waterborne pathogens.

Investigation of a novel biofilm model close to the original oral microbiome.

A more optimized culture medium used in vitro to mimic the bacterial composition of original oral flora as similar as possible remains difficult at present, and the goal of this study is to develop a novel oral biofilm medium to restore the original oral microbiome. Firstly, we conducted a systematic literature review by searching PubMed and summarized the current reported culture media in vitro. Seven culture media were found. We used mixed saliva as the origin of oral species to compare the effects of the above media in culturing oral multispecies biofilms. Results indicated that among the seven media brain heart infusion containing 1% sucrose (BHIs) medium, PG medium, artificial saliva (AS) medium, and SHI medium could obviously gain large oral biofilm in vitro. The nutrients contained in different culture media may be suitable for the growth of different oral bacteria; therefore, we optimized several novel media accordingly. Notably, results of crystal violet staining showed that the biofilm cultured in our modified artificial saliva (MAS) medium had the highest amount of biofilm biomass. 16S rRNA gene sequencing showed that the operational taxonomic units (OTUs) and Shannon index of biofilm cultured in MAS medium were also the highest among all the tested media. More importantly, the 16S rRNA gene sequencing analysis indicated that the biofilm cultured in MAS medium was closer to the original saliva species. Besides, biofilm cultured by MAS was denser and produced more exopolysaccharides. MAS supported stable biofilm formation on different substrata. In conclusion, this study demonstrated a novel MAS medium that could culture oral biofilm in vitro closer to the original oral microbiome, showing a good application prospect. KEY POINTS: • We compare the effects of different media in culturing oral biofilms • A novel modified artificial saliva (MAS) medium was obtained in our study • The MAS medium could culture biofilm that was closer to oral microbiome.

Effects of small extracellular vesicles derived from normoxia- and hypoxia-treated prostate cancer cells on the submandibular salivary gland epithelium in vitro.

Small extracellular vesicles (sEVs) are an important part of intercellular communication. They are phospholipid bilayer particles that carry active biomolecules such as proteins, various nucleic acids, and lipids. In recipient cells, sEVs can alter cellular functions, including cancer development and premetastatic niche formation in distant organs. Moreover, sEVs can carry cancer-specific features, which makes them promising biomarker candidates. However, the interactions of sEVs with biological barriers and consequences thereof, are not clarified yet. The blood-saliva barrier is crucial for preventing the entry of pathogens and (in)organic substances into the bloodstream, as well as molecule filtration from blood to saliva. The effects of brain derived DU145 prostate cancer (PCa) sEVs on a human submandibular salivary gland barrier (SSGB) in vitro were investigated. Small EVs were harvested from normoxic (N, atmospheric O2) or hypoxic (H, 1% O2) conditions, fluorescently labeled with CellTrackerTM Orange and thoroughly characterized. HTB-41 B2 cells were used as SSGB model cultured on 24-well ThinCert® inserts. After model optimization indicating effects of serum and serum-sEVs on barrier properties, PCa sEVs were applied to the basolateral (blood) side in either 10% serum, or serum-free conditions, and barrier integrity was continuously monitored for 40 hours. This study found that H and N PCa sEVs were uptaken by the SSGB in vitro model in similar quantities regardless of the media composition in the basolateral compartment. Permeation of fluorescent PCa sEVs into the apical compartment was not detectable with the applied methods. However, treatment with H and N sEVs under different serum conditions revealed distinct molecular clusters after hierarchical analysis of mRNA data measured by high-throughput qPCR, which were partly reflected at the protein level. For example, serum-reduction dependent decrease of barrier properties was accompanied with the decrease of CDH1 or Claudin-7 expression. Interestingly, the presence of H sEVs significantly increased the number of sEV-sized particles in the apical compartment of the SSGB model compared to basolaterally added N sEVs. This functional effect on the number of particles in the saliva (apical) compartment induced by different sEVs applied in the blood (basolateral) compartment might be a new approach to understand one possible mechanism how differences of salivary EVs might occur which then could be used as biomarker.

Diurnal and day-to-day biological variation of salivary cortisol and cortisone.

OBJECTIVES: There is a growing interest in the relevance of salivary cortisol and cortisone concentrations in stress-related research. To correctly attribute the magnitude of salivary cortisol and cortisone variation as an effect of a stressful event, a coherent understanding of the day-to-day intra-individual and inter-individual variability across the diurnal cycle of the two steroids is required. However, such information is currently lacking. METHODS: This study aimed to overcome these existing limitations by performing an investigation of the biological variation (BV) of salivary cortisol and cortisone within one day and between five days using an LC-MS/MS method. Saliva samples were collected from 20 healthy volunteers immediately after waking up, at 8:00, 12:00, 15:00, 19:00 and 23:00 on each day over five days. All samples were analyzed in duplicate in one run. Nested ANOVA was used to calculate the sums of squares for analytical and biological components of variation. RESULTS: The within-subject BV of salivary cortisol and cortisone (CVI) ranged from a minimum of 29.3 and 19.0 % to a maximum of 56.5 and 49.1 %, respectively, while the between-subject biological variation (CVG) ranged from 29.7 and 29.0 % to 51.6 and 43.6 %. The reference change values (RCVs) ranged from 96 to 245 % for cortisol and from 55 to 194 % for cortisone. A medium index of individuality was observed for both compounds at all time points. CONCLUSIONS: This study provides updated BV estimates and RCVs for different times of day that can be used to assess the magnitude of change in biomarkers in future stress-related research.

Salivary and serum haptoglobin, adenosine deaminase, and immunoglobulin G in growing pigs.

BACKGROUND: Identification of animals in need of medical treatment is important in porcine health management, where analytical samples applicable at farm level could be utilized. Several biomarkers are measurable in saliva, which is less stressful to collect than blood. Saliva sampling is easy to learn and repeatable, making it suitable for monitoring purposes. Previous research suggests that porcine health biomarkers are dependent on production stage and gender, and that combining biomarkers improves diagnostic sensitivity. However, proper monitoring of biomarkers during the complete production cycle has not been studied. We aimed to describe the dynamics of salivary and serum haptoglobin (Hp), adenosine deaminase (ADA), and immunoglobulin G (IgG) in four production stages (suckling, early growing, late growing, finishing), on commercial Finnish pig farms using a total of 117 piglets. The relationship between gender and biomarker dynamics was investigated, as well as the relationships between these biomarkers in saliva and serum. RESULTS: The highest salivary concentrations of Hp, ADA and IgG were measured in suckling piglets. The differences between production stages were generally larger in saliva than for the corresponding serum biomarkers. All correlation coefficients between salivary biomarkers were positive in each production stage and the strength of the correlation varied from 0.245 to 0.762. No similar trend was observed regarding correlation coefficients either between serum biomarkers or between salivary and serum biomarkers. Gender was associated with some biomarker concentrations. CONCLUSIONS: The biomarker dynamics supported previous findings that collection of analytical samples should be conducted in age-matched populations. Positive and even strong relationships between salivary biomarkers indicate the potential to use especially saliva for health monitoring. Our results also suggest the importance of considering gender effects when assessing some salivary or serum biomarkers.

Succession changes of microbial community for inferring the time since deposition of saliva.

Saliva is a common biological examination material at crime scenes and has high application value in forensic case investigations. It can reflect the suspect's time of crime at the scene and provide evidence of the suspect's criminal facts. Even though many researchers have proposed their experimental protocols for estimating the time since deposition (TsD) of saliva, there is still a relative lack of research on the use of microorganisms to estimate TsD. In the current study, the succession change of microbial community in saliva with different TsD values was explored to discern the microbial markers related to TsD of saliva. We gathered saliva samples from six unrelated healthy Han individuals living in Guizhou, China and exposed these samples to indoor conditions at six time points (0, 1, 3, 7, 15, and 28 days). Temporal changes of microbial compositions in these samples were investigated by 16S rRNA sequencing (V3-V4 regions). By assessing temporal variation patterns of microbial abundance at the genus level, four bacteria (Brucella, Prevotella, Pseudomonas, and Fusobacterium) were observed to show good time dependence in these samples. In addition, the hierarchical clustering and principal co-ordinates analysis results revealed that these saliva samples could be classified into t-short (≤7 days) and t-long (>7 days) groups. In the end, the random forest model was developed to predict the TsD of these samples. For the model, the root mean square error, R2, and mean absolute error between predicted and actual TsD values were 1.5213, 0.9851, and 1.1969, respectively. To sum up, we identified TsD-related microbial markers in saliva samples, which could be viewed as valuable markers for inferring the TsD of saliva.

The use of bioluminescent enzyme bioassay for the analysis of human saliva: Advantages and disadvantages.

The purpose of the work was to find optimal conditions for bioluminescent enzymatic analysis of saliva (based on the use of NADH:FMN oxidoreductase + luciferase) and then to determine the biological effect of using bioluminescence assay of saliva to study the physiological state of the body under normal and pathological conditions. The saliva of snowboarders and students were studied in the "rest-training" model. The saliva of patients diagnosed with acute pharyngitis was examined in the "sick-healthy" model. Bioluminescence assay was performed with a lyophilized and immobilized bi-enzyme system using cuvette, plate, and portable luminometers. The concentrations of secretory immunoglobulin A (sIgA) and cortisol were determined by enzyme immunoassay, and the total protein content was measured by spectrophotometric method. The activity of the bioluminescent system enzymes increased as the amount and volume of saliva in the sample was decreased. The cuvette and plate luminometers were sensitive to changes in the luminescence intensity in saliva assay. Luminescence intensity correlated with the concentrations of sIgA and cortisol. The integrated bioluminescent index for saliva was reduced in the "rest-training" model and increased in the "sick-healthy" model. Thus, the non-invasive bioluminescent saliva analysis may be a promising tool for assessing the health of the population.

Comparative salivary proteomics analysis of children with and without early childhood caries using the DIA approach: A pilot study.

OBJECTIVE: To screen differentially expressed proteins (DEPs) in the saliva of Early childhood caries (ECC) with different degrees of severity. METHODS: The proteomic profiles of salivary of children with ECC of varying severity by data independent acquisition data independent acquisition (DIA) technique. A total of 12 preschool children aged 3-5 years were included in this study. RESULTS: In this study, a total of 15,083 peptides and 1944 proteins were quantified; The results of DEPs screening showed that 34 DEPs were identified between the group H and the group LC, including 18 up-regulated proteins and 16 down-regulated proteins; 34 DEPs were screened between the group H and the group HC, including 17 up-regulated proteins and 17 down-regulated proteins; 42 DEPs were screened between the group LC and the group HC, including 18 up-regulated proteins and 24 down-regulated proteins. Among these DEPs, we screened several key proteins that may play a role in ECC, such as MK, histone H4, TGFß3, ZG16B, MUC20, and SMR-3B. CONCLUSION: Salivary proteins, as important host factors of caries, are differentially expressed between the saliva of ECC children and healthy children. Specific DEPs are expected to become potential biomarkers for the diagnosis of ECC.

Assessment of severity and mineral composition of saliva in schoolchildren with molar-incisor hypomineralization (MIH).

The aim of the study was to evaluate the severity of molar incisor hypomineralisation (MIH), related oral health and investigate salivary mineral composition. The study was conducted with 50 participants aged between 6-15 years who were effected with MIH and 50 without MIH. The International Caries Detection and Assessment System (ICDAS) scores, Decayed, Missing, Filled Teeth/Surface (DMFT/S), dft/s and gingival/plaque indices were evaluated. The pH, flow rate, buffering capacity and mineral composition of saliva was measured. "Student t" test, one-way analysis of variance in repeated measurements of groups, and Tukey multiplex in subgroup comparisons was used. Kruskal-Wallis, Mann-Whitney U, Wilcoxon and chi-square tests were used to analyze qualitative data and compare groups. A total of 100 children (57 females 43 males, mean age 10.12 ± 1.85) participated in the study. There was no difference between ICDAS, DMFT/S scores, but dft/s index values were statistically significant (p = 0.001). The simplified oral hygiene index of MIH patients were statistically higher, but no significant differences were found in modified gingival indices (p = 0.52). Although the salivary pH and flow rate of the patients in the study group were lower, the buffering capacity was higher than those in the control group, but no significant difference was observed (p = 0.64). The mean values of phosphorus, carbon and calcium content in the saliva samples of MIH patients were higher than those of patients without MIH, and this difference was low for phosphorus (p = 0.76) and carbon (p = 0.74), but significantly higher for calcium. To the best of our knowledge, this is the first study to evaluate the association between calcium, phosphate and carbon levels in saliva of children with MIH. The significantly high amount of calcium in the saliva of patients with MIH suggests that further investigations are needed.

Antibodies to Aedes aegypti D7L salivary proteins as a new serological tool to estimate human exposure to Aedes mosquitoes.

Introduction: Aedes spp. are the most prolific mosquito vectors in the world. Found on every continent, they can effectively transmit various arboviruses, including the dengue virus which continues to cause outbreaks worldwide and is spreading into previously non-endemic areas. The lack of widely available dengue vaccines accentuates the importance of targeted vector control strategies to reduce the dengue burden. High-throughput tools to estimate human-mosquito contact and evaluate vector control interventions are lacking. We propose a novel serological tool that allows rapid screening of human cohorts for exposure to potentially infectious mosquitoes. Methods: We tested 563 serum samples from a longitudinal pediatric cohort study previously conducted in Cambodia. Children enrolled in the study were dengue-naive at baseline and were followed biannually for dengue incidence for two years. We used Western blotting and enzyme-linked immunosorbent assays to identify immunogenic Aedes aegypti salivary proteins and measure total anti-Ae. aegypti IgG. Results: We found a correlation (rs=0.86) between IgG responses against AeD7L1 and AeD7L2 recombinant proteins and those to whole salivary gland homogenate. We observed seasonal fluctuations of AeD7L1+2 IgG responses and no cross-reactivity with Culex quinquefasciatus and Anopheles dirus mosquitoes. The baseline median AeD7L1+2 IgG responses for young children were higher in those who developed asymptomatic versus symptomatic dengue. Discussion: The IgG response against AeD7L1+2 recombinant proteins is a highly sensitive and Aedes specific marker of human exposure to Aedes bites that can facilitate standardization of future serosurveys and epidemiological studies by its ability to provide a robust estimation of human-mosquito contact in a high-throughput fashion.