Search Results (2,952)

Composite resins are the material of choice for direct restorations, and their success depends mainly on their color stability, since discoloration causes color mismatch, and consequent patient dissatisfaction. A single- and a multi-shade resin were compared in order to evaluate their pigmentation after immersion in staining substances and to investigate the effect of the polymerization time on their color stability. Two-hundred-and-forty composite specimens were created, half made of a single-shade (Group ONE, n = 120) and half of a multi-shade composite (Group OXP, n = 120). Each group was further divided into ONE30 (n = 60) and OXP30 (n = 60), polymerized for 30″, and ONE80 (n = 60) and OXP80 (n = 60), polymerized for 80″. Randomly, the specimens were immersed in turmeric solution, soy sauce, energy drink, or artificial saliva. By means of a spectrophotometer, ΔE₀₀ and WI_d were calculated at 24 h (T₀), at 7 (T₁), and 30 (T₂) days. Single-shade composites showed statistically significant differences in color change from the turmeric solution, energy drink, and soy sauce than the multi-shade composites (p < 0.005), showing a higher discoloration potential. The polymerization time did not have significative effects on color stability. Single-shade composites showed more color change than multi-shade systems after immersion in staining substances, and the curing time did not influence color variations. Full article

Although titanium and its alloys are widely used as dental implants, they cannot induce the formation of new bone around the implant, which is a basis for the functional integrity and long-term stability of implants. This study focused on the functionalization of the titanium/titanium oxide surface as the gold standard for dental implants, with electrospun composite fibers consisting of polyvinylpyrrolidone and Ca²⁺ ions. Polymer fibers as carriers of Ca²⁺ ions should gradually dissolve, releasing Ca²⁺ ions into the environment of the implant when it is immersed in a model electrolyte of artificial saliva. Scanning electron microscopy, energy dispersive X-ray spectroscopy and attenuated total reflectance Fourier transform infrared spectroscopy confirmed the successful formation of a porous network of composite fibers on the titanium/titanium oxide surface. The mechanism of the formation of the composite fibers was investigated in detail by quantum chemical calculations at the density functional theory level based on the simulation of possible molecular interactions between Ca²⁺ ions, polymer fibers and titanium substrate. During the 7-day immersion of the functionalized titanium in artificial saliva, the processes on the titanium/titanium oxide/composite fibers/artificial saliva interface were monitored by electrochemical impedance spectroscopy. It can be concluded from all the results that the composite fibers formed on titanium have application potential for the development of osteoinductive and thus more biocompatible dental implants. Full article

Red deer (Cervus elaphus), like other ruminants, excrete approximately 70% of the nitrogen they ingest. Developing ways in which to reduce the rate of loss, such as manipulating the diet or selecting for efficiency of growth, requires close monitoring of the plasma urea N (PUN) concentration which, in turn, requires a simple, safe, and reliable method for collecting samples. Saliva is easier to collect than blood, but the relationship between the salivary urea N (SUN) and the PUN is not known for red deer. This was therefore evaluated in two strains of mixed-sex red deer calves (Cervus elaphus): a phenotype with a high seasonality of growth (H, n = 10) and a phenotype with a low seasonality of growth (L, n = 13). Both phenotypes were divided into two groups, which were each offered one of two forage-based diets ad libitum: a medium-quality diverse treatment and a low-quality perennial ryegrass–white clover treatment. Blood and saliva samples for the determination of the PUN and SUN were collected at dawn every four weeks for five months (April to September 2022). There was a strong linear relationship between the PUN and SUN in the pooled sample (R² = 0.65, p < 0.001). The estimations of the PUN were significantly improved by adding diet and the date of sampling into the model (p < 0.001), but not phenotype (p > 0.75). SUN represents a reliable index of the PUN, and collecting saliva therefore represents a simple and inexpensive alternative to collecting blood samples in studies of nitrogen metabolism in red deer. Full article

Objectives: Using toothpaste with activated carbon might increase the decay of orthodontic elastomeric chains’ (ECs) tensile strength, thereby compromising orthodontic treatment. Therefore, this study aimed to evaluate the influence of activated charcoal toothpaste on orthodontic ECs. Materials and Methods: A total sample of 180 EC segments from 3M Unitek^®, Ormco^® and Ortho Classic^® brands were equally divided into 12 groups, each comprising 15 specimens. These pieces were kept in artificial saliva at 37 °C and brushed twice daily for 28 days, with three distinct types of toothpaste: Colgate^® Total, Colgate^® Max White, and Dr Organic^® Extra Whitening Charcoal Toothpaste. The latter two toothpastes contain activated charcoal. Tensile strength, resistance to rupture and colour variation were evaluated at time zero and day 28. Descriptive statistics, one-way ANOVA and Tukey HSD tests were performed at p ≤ 0.05. Results: Toothpaste with and without activated carbon significantly reduced the tensile strength and resistance to rupture of the ECs, and altered EC colour (p < 0.0001). There was inconsistency in the effect of the activated carbon on EC characteristics, most probably due to the different compositions of the ECs and percentages of whitening agents in the toothpastes. Conclusions: The material composition of ECs contributes to their tensile strength decay, resistance to rupture and colour change over time. The variable percentage of activated carbon in a toothpaste likely underlies the different effects observed, depending on the EC brand. Clinical Relevance: It might be reasonable to advise patients wearing ECs to avoid using toothpaste with activated carbon until further evidence becomes available. Full article

Background: Alcohol abuse is one of the most common causes of mortality worldwide. This study aimed to investigate the efficacy of a treatment in reducing circulating ethanol and oxidative stress biomarkers. Methods: Twenty wine-drinking subjects were investigated in a randomized controlled, single-blind trial (ClinicalTrials.gov. Identifier: NCT06548503; Ethical Committee of the University of Padova (HEC-DSB/12-2023) to evaluate the effect of the intake of a product containing silymarin, pyrroloquinoline quinone sodium salt, and myricetin (referred to as Si.Pi.Mi. for this project) on blood alcohol, ethyl glucuronide (EtG: marker for alcohol consumption) and markers of oxidative stress levels (Reactive Oxygen Species—ROS, Total Antioxidant Capacity—TAC, CoQ10, thiols redox status, 8-isoprostane, NO metabolites, neopterin, and uric acid). The effects of the treatment versus placebo were evaluated acutely and after 1 week of supplementation in blood and/or saliva and urine samples. Results: Si.Pi.Mi intake reduced circulating ethanol after 120 min (−33%). Changes in oxidative stress biomarkers, particularly a TAC (range +9–12%) increase and an 8-isoprostane (marker of lipidic peroxidation) decrease (range −22–27%), were observed too. Conclusion: After the administration of Si.Pi.Mi, the data seemed to suggest a better alcohol metabolism and oxidative balance in response to wine intake. Further verification is requested. Full article

West Nile Virus (WNV) poses a significant global public health threat as a mosquito-borne pathogen. While laboratory mouse models have historically played a crucial role in understanding virus biology, recent research has focused on utilizing immunocompromised models to study arboviruses like dengue and Zika viruses, particularly their interactions with Aedes aegypti mosquitoes. However, there has been a shortage of suitable mouse models for investigating WNV and St. Louis encephalitis virus interactions with their primary vectors, Culex spp. mosquitoes. Here, we establish the AG129 mouse (IFN α/β/γ R^−/−) as an effective vertebrate model for examining mosquito–WNV interactions. Following intraperitoneal injection, AG129 mice exhibited transient viremia lasting several days, peaking on the second or third day post-infection, which is sufficient to infect Culex quinquefasciatus mosquitoes during a blood meal. We also observed WNV replication in the midgut and dissemination to other tissues, including the fat body, in infected mosquitoes. Notably, infectious virions were present in the saliva of a viremic AG129 mouse 16 days post-exposure, indicating successful transmission capacity. These findings highlight the utility of AG129 mice for studying vector competence and WNV–mosquito interactions. Full article

Passive smoking from environmental tobacco smoke not only increases the risk of lung cancer and cardiovascular disease but may also be a stressor triggering neuropsychiatric and other disorders. To prevent these diseases, understanding the relationship between passive smoking and stress is vital. In this study, we developed a simple and sensitive method to simultaneously measure nicotine (Nic) and cotinine (Cot) as tobacco smoke exposure biomarkers, and cortisol (CRT), serotonin (5-HT), melatonin (MEL), dopamine (DA), and oxytocin (OXT) as stress-related biomarkers. These were extracted and concentrated from saliva by in-tube solid-phase microextraction (IT-SPME) using a Supel-Q PLOT capillary as the extraction device, then separated and detected within 6 min by liquid chromatography–tandem mass spectrometry (LC−MS/MS) using a Kinetex Biphenyl column (Phenomenex Inc., Torrance, CA, USA). Limits of detection (S/N = 3) for Nic, Cot, CRT, 5-HT, MEL, DA, and OXT were 0.22, 0.12, 0.78, 0.39, 0.45, 1.4, and 3.7 pg mL⁻¹, respectively, with linearity of calibration curves in the range of 0.01–25 ng mL⁻¹ using stable isotope-labeled internal standards. Intra- and inter-day reproducibilities were under 7.9% and 14.6% (n = 5) relative standard deviations, and compound recoveries in spiked saliva samples ranged from 82.1 to 106.6%. In thirty nonsmokers, Nic contents positively correlated with CRT contents (R² = 0.5264, n = 30), while no significant correlation was found with other biomarkers. The standard deviation of intervals between normal beats as the standard measure of heart rate variability analysis negatively correlated with CRT contents (R² = 0.5041, n = 30). After passive smoke exposure, Nic levels transiently increased, Cot and CRT levels rose over time, and 5-HT, DA, and OXT levels decreased. These results indicate tobacco smoke exposure acts as a stressor in nonsmokers. Full article

Dimethyl fumarate (DMF), originally proposed to treat multiple sclerosis, is considered to have a spectrum of anti-inflammatory effects that effectively control periodontitis, mainly when applied with a hydrogel delivery system. Chemokine expression by gingival fibroblasts is a significant driver of periodontitis; thus, hydrogel-based strategies to deliver DMF, which in turn dampen chemokine expression, are of potential clinical relevance. To test this approach, we have established a bioassay where chemokine expression is induced by exposing gingival fibroblast to IL1β and TNFα, or with saliva. We show herein that DMF effectively reduced the expression of CXCL8, CXCL1, CXCL2, and CCL2—and lowered the phosphorylation of ERK and JNK—without affecting cell viability. This observation was confirmed by immunoassays with CXCL8. Consistently, the forced chemokine expression in HSC2 oral squamous epithelial cells was greatly diminished by DMF. To implement our hydrogel-based delivery system, gingival fibroblasts were cocultured with gellan gum hydrogels enriched for DMF. In support of our strategy, DMF-enriched gellan gum hydrogels significantly reduced the forced chemokine expression in gingival fibroblasts. Our data suggest that DMF exerts its anti-inflammatory activity in periodontal cells when released from gellan gum hydrogels, suggesting a potential clinical relevance to control overshooting chemokine expression under chronic inflammatory conditions. Full article

Cancer cachexia is a syndrome characterized by weight and muscle loss and functional impairment, strongly influencing survival in cancer patients. In this study, we aimed to establish the role of saliva cytokine measurement in cancer cachexia investigation and define two potential independent salivary biomarkers of the condition. Methods: serum and saliva specimens were obtained from 78 patients. Forty-six patients were non-cachectic, and 32 patients were cachectic (per SCRINIO group criteria), all with metastatic solid tumors. Commercial ELISA kits were used to determine the salivary and serum concentrations of interleukin 13 (IL-13) and transforming growth factor beta (TGF-β) in two patient groups and healthy controls. Laboratory values were obtained from the hospital information system, and weight and height were measured at the time of sampling. Results: A statistically significant difference was observed between the groups in saliva IL-13 concentrations but no difference in serum concentrations. Statistically significant differences were also observed between the groups in saliva and serum concentrations of TGF-β. Logistic regression analysis has identified salivary IL-13 and TGF-β as independent factors for cancer cachexia. Conclusions: We demonstrated saliva as a valuable specimen for cachexia investigation and established IL-13 and TGF-β as potential cancer cachexia biomarkers. Further research is needed to evaluate these findings. Full article

Amelogenesis imperfecta (AI) is a genetic disease characterized by poor formation of tooth enamel. AI occurs due to mutations, especially in AMEL, ENAM, KLK4, MMP20, and FAM83H, associated with changes in matrix proteins, matrix proteases, cell-matrix adhesion proteins, and transport proteins of enamel. Due to the wide variety of phenotypes, the diagnosis of AI is complex, requiring a genetic test to characterize it better. Thus, there is a demand for developing low-cost, noninvasive, and accurate platforms for AI diagnostics. This case-control pilot study aimed to test salivary vibrational modes obtained in attenuated total reflection fourier-transformed infrared (ATR-FTIR) together with machine learning algorithms: linear discriminant analysis (LDA), random forest, and support vector machine (SVM) could be used to discriminate AI from control subjects due to changes in salivary components. The best-performing SVM algorithm discriminates AI better than matched-control subjects with a sensitivity of 100%, specificity of 79%, and accuracy of 88%. The five main vibrational modes with higher feature importance in the Shapley Additive Explanations (SHAP) were 1010 cm⁻¹, 1013 cm⁻¹, 1002 cm⁻¹, 1004 cm⁻¹, and 1011 cm⁻¹ in these best-performing SVM algorithms, suggesting these vibrational modes as a pre-validated salivary infrared spectral area as a potential biomarker for AI screening. In summary, ATR-FTIR spectroscopy and machine learning algorithms can be used on saliva samples to discriminate AI and are further explored as a screening tool. Full article

Brain-derived neurotrophic factor (BDNF) is a protein involved in synaptic transmission and neuronal plasticity, which underlie the processes of learning and memory formation. Acute exercise and exercise training increase BDNF concentration. We aimed to evaluate the effects of a 3-month integrated neuromuscular training (INT) on salivary BDNF concentration and the mastery of fundamental motor skills in school-aged children. An additional goal was to explore the associations between potential changes in BDNF and fundamental motor skills. Sixty-seven primary school-aged children were randomly allocated to control (N = 32; 7.52 ± 0.31 y) or INT groups (N = 35; 7.56 ± 0.29 y). A 3-month INT was applied during the warm-up of physical education (PE) classes, twice weekly. Salivary BDNF was measured using a sandwich-enzyme-linked immunosorbent assay and the mastery of fundamental motor skills was assessed using the CAMSA test, at baseline and after 3 months. The children in the INT group, as compared to the children in the control group, exhibited higher salivary BDNF (F = 8.865; p = 0.004), higher scores for sidestep (F = 13.240, p = 0.001), 1-foot hop (F = 11.684, p = 0.001), kick (F = 4.010, p = 0.050), the sum of locomotor skills (F = 18.799, p < 0.0001), and the sum of control and manipulative skills (F = 8.151, p = 0.006), as well as the total sum of fundamental motor skills (F = 11.266, p = 0.001) after the 3 months. Interestingly, the increase in salivary BDNF concentration after the 3-month INT was associated with an improvement in locomotor skills (beta = 0.385; p = 0.039; adjusted R² = 0.088) and the total improvement in fundamental motor skills (beta = 0.428; p = 0.020; adjusted R² = 0.124). A school-based 3-month INT increased salivary BDNF and improved the mastery of fundamental motor skills in children, highlighting the positive impact of this intervention for a pediatric population. Full article

Xerostomia induced by antidepressants such as imipramine has long been thought to be due to their anticholinergic effects. However, even antidepressants with low anticholinergic effects may have a high incidence of xerostomia. In salivary glands, norepinephrine activates alpha-adrenergic receptors in blood vessels and beta-adrenergic receptors in acinar cells, respectively, causing a decrease in the blood flow and an increase in the protein secretion, resulting in the secretion of viscous saliva with low water content and high protein content. A previous study demonstrated that perfusion of the submandibular glands of rats with serotonin significantly decreased saliva secretion. The results of the present study revealed the following: (1) that norepinephrine and serotonin, but not epinephrine nor dopamine, were detected in the interstitial fluids in rat submandibular glands; (2) that norepinephrine and serotonin concentrations in the dialysate was 4.3 ± 2.8 nM and 32.3 ± 19.6 nM at stable level, respectively; (3) that infusion with imipramine, a reuptake inhibitor of norepinephrine and serotonin, significantly and dose-dependently increased both norepinephrine and serotonin concentrations in the dialysate; and (4) that intraperitoneal administration of imipramine significantly increased both norepinephrine and serotonin concentrations in the dialysate. These results suggested that one of the mechanisms of xerostomia induced by reuptake inhibitors of norepinephrine and serotonin involves the activation of adrenergic and serotonin receptors in the salivary glands, respectively. Full article

Breastfeeding and human milk are the gold standard for infant feeding. Studying human milk with a systems biology approach in a large longitudinal cohort is needed to understand its complexity and health implications. The Phoenix study is a multicenter cohort study focusing on the interactions of maternal characteristics, human milk composition, infant feeding practices, and health outcomes of Chinese mothers and infants. A total of 779 mother–infant dyads were recruited from November 2021 to September 2022, and 769 mother–infant dyads were enrolled in the study. Scheduled home visits took place at 1, 4, 6, and 12 months postpartum, and 696 dyads (90.5% participants) completed the 12-month visit. At each visit, maternal and infant anthropometry was assessed. Questionnaires were administered to collect longitudinal information on maternal characteristics and lifestyle, infant feeding, and health. Digital diaries were used to record maternal dietary intake, infant feeding, and stool character. Human milk, maternal feces, infant feces, and infant saliva were collected. An external pharmaceutical-level quality assurance approach was implied to ensure the trial quality. Multi-omics techniques (including glycomics, lipidomics, proteomics, and microbiomics) and machine learning algorithms were integrated into the sample and data analysis. The protocol design of the Phoenix study provides a framework for prospective cohort studies of mother–infant dyads and will provide insights into the complex dynamics of human milk and its interplay with maternal and infant health outcomes in the Chinese population. Full article

Transcutaneous auricular vagus nerve stimulation (taVNS) is a non-invasive neuromodulation technique that modulates the noradrenergic activity of the locus coeruleus (LC). Yet, there is still uncertainty about the most effective stimulation and reliable outcome parameters. In a double blind, sham-controlled study including a sample of healthy young individuals (N = 29), we compared a shorter (3.4 s) and a longer (30 s) stimulation duration and investigated the effects of taVNS (real vs. sham) on saliva samples (alpha amylase and cortisol concentration), pupil (pupillary light reflex and pupil size at rest) and EEG data (alpha and theta activity at rest, ERPs for No-Go signals), and cognitive tasks (Go/No-Go and Stop Signal Tasks). Salivary alpha amylase concentration was significantly increased in the real as compared to sham stimulation for the 30 s stimulation condition. In the 3.4 s stimulation condition, we found prolonged reaction times and increased error rates in the Go/No-Go task and increased maximum acceleration in the pupillary light reflex. For the other outcomes, no significant differences were found. Our results show that prolonged stimulation increases salivary alpha-amylase, which was expected from the functional properties of the LC. The finding of longer response times to short taVNS stimulation was not expected and cannot be explained by an increase in LC activity. We also discuss the difficulties in assessing pupil size as an expression of taVNS-mediated LC functional changes. Full article

This study aims to evaluate the expression of salivary and plasmatic miRNAs as diagnostic biomarkers in patients with oral squamous cell carcinoma (OSCC) and oral potentially malignant disorders (OPMDs). A total of 25 patients were divided into three groups, according to their diagnosis: OSCC patients (n = 14); OPMDs patients (n = 6); and healthy controls (n = 5). At the time at diagnosis/enrolment, patients underwent salivary and plasmatic collection. The expression of miRNA -21, -31, -138, -145, -184, and -424 were evaluated by real-time PCR. An F-test and ANOVA test were performed to evaluate the miRNA levels (significance at p < 0.05). By comparing miRNA expression levels from saliva, a statistically significant difference emerged in the expression of miR-138 and miR-424 between the three groups (p < 0.05). In particular, these two miRNAs showed decreased expression levels in saliva samples from OSCC and OPMD patients compared to those from healthy controls. On the other hand, miRNA expression levels in plasma were low in all the groups, and no statistically significant differences were found. Overall, our results showed that liquid biopsy from saliva may be a useful tool for the identification of diagnostic molecular biomarkers in OSCC and OPMDs. Full article