Drivers of the In-Mouth Interaction between Lupin Protein Isolate and Selected Aroma Compounds: A Proton Transfer Reaction-Mass Spectrometry and Dynamic Time Intensity Analysis.

Plant proteins often carry off-notes, necessitating customized aroma addition. In vitro studies revealed protein-aroma binding, limiting release during consumption. This study employs in vivo nose space proton transfer reaction-time-of-flight-mass spectrometry and dynamic sensory evaluation (time intensity) to explore in-mouth interactions. In a lupin protein-based aqueous system, a sensory evaluation of a trained "green" attribute was conducted simultaneously with aroma release of hexanal, nonanal, and 2-nonanone during consumption. Results demonstrated that enlarging aldehyde chains and relocating the keto group reduced maximum perceived intensity (Imax_R) by 71.92 and 72.25%. Protein addition decreased Imax_R by 30.91, 36.84, and 72.41%, indicating protein-aroma interactions. Sensory findings revealed a perceived intensity that was lower upon protein addition. Aroma lingering correlated with aroma compounds' volatility and hydrophobicity, with nonanal exhibiting the longest persistence. In vitro mucin addition increased aroma binding four to 12-fold. Combining PTR-ToF-MS and time intensity elucidated crucial food behavior, i.e., protein-aroma interactions, that are pivotal for food design.

Effect of oral exposure on chemical, physical, mechanical, and morphologic properties of clear orthodontic aligners.

INTRODUCTION: The dental industry is heavily committed to developing more esthetic solutions for orthodontic treatments. Invisalign is a system of transparent orthodontic aligners introduced as an alternative to conventional orthodontic fittings with brackets and metal wires. This study aimed to assess the chemical, physical, mechanical and morphologic changes in these polymeric aligners after exposure to the oral environment. METHODS: Twenty-four Invisalign orthodontic aligners were equally divided into 2 groups: an in vivo aged group in which patients used aligners for 14 days and the reference group, unexposed to the oral environment. Different experimental techniques were used to study the chemical structure, the color changes and translucency, the density and subsequent volume of the aligners, mechanical properties, surface roughness, morphology and elemental composition. The data were subjected to several statistical analyses. RESULTS: Clear orthodontic aligners exhibit chemical stability but undergo a statistically significant optical change in color and translucency. There was a gradual increase in the water absorption rate and the dimensional variation of the polymer, indicating a strong correlation among these factors. The mechanical properties of the polymer showed a statistically significant decrease in its elastic modulus and hardness. There was a slight tendency toward increased surface roughness of the material, but no statistical differences were found between reference and aged groups. The surface morphology of the used aligners demonstrates microcracks, distortions and biofilm formation. CONCLUSION: Intraoral aging adversely affected the physical, mechanical, and morphologic properties of the Invisalign appliance.

Mouth Level Intake of Nicotine from Three Brands of Little Filtered Cigars with Widely Differing Product Characteristics Among Adult Consumers.

Little filtered cigars are tobacco products with many cigarette-like characteristics. However, despite cigars falling under the U.S. Food and Drug Administration regulatory authority, characterizing flavors, which are still allowed in little filtered cigars, and filter design may influence how people use the products and the resulting exposure to harmful and potentially harmful constituents. We estimated nicotine mouth level intake (MLI) from analyses of little cigar filter butt solanesol levels, brand characteristics, carbon monoxide boost, and puff volume in 48 dual cigarette/cigar users during two repeat bouts of ad lib smoking of three little filtered cigar brands. Mean nicotine MLI for the three brands was significantly different with Swisher Sweets (0.1% ventilation) Cherry at 1.20 mg nicotine, Cheyenne Menthol (1.5%) at 0.63 mg, and Santa Fe unflavored (49%) at 0.94 mg. The association between nicotine MLI and puff volume was the same between Cheyenne Menthol and Santa Fe unflavored. However, these were different from Swisher Sweets Cherry. At least five main factors─flavor, ventilation, filter design, nicotine delivery related to tar, and user puff volume─may directly or indirectly impact MLI and its association with other measures. We found that users of little filtered cigars that have different filter ventilation and flavor draw dissimilar amounts of nicotine from the product, which may be accompanied by differences in exposure to other harmful smoke constituents.

Application of untargeted volatile profiling to investigate the fate of aroma compounds during wine oral processing.

We employed an untargeted volatile profiling approach in combination with spit off-odorant measurement procedure to investigate the fate of aroma compounds in mouth by determining how oral processing and intrinsic biological variables influence the overall volatile composition. A red wine before and after oral processing (expectorated wine), and control samples (expectorated water) were analyzed using GC-TOF-MS to determine as many volatile compounds as possible. We identified compounds in expectorated wines that originated in mouth from either an endogenous or exogenous source, while confirming that compounds might have metabolized by the action of salivary enzymes. Our data also show the changes in volatiles via hydrolysis from the corresponding molecules and may provide evidence of de novo formation of volatiles via transesterification reaction in mouth. While investigating the impact of intrinsic biological variables, we found age and gender specific differences in wine volatile composition due to oral processing and identified the key volatiles.

Saliva as Diagnostic Material and Current Methods of Collection from Oral Cavity.

BACKGROUND: In recent years, more and more attention has been paid to the use of saliva in laboratory diagnostics aimed at monitoring both human health and diseases. Providing fundamental overview takes the reader through composition, functions, protective effects and significant role as biomarker. Therefore, the purpose of the research was a current review on the topic of saliva composition in relation to applied secretory stimuli used in clinical laboratory. METHODS: The paper presents human factors, systems, and neurotransmitters on which saliva production depends. Chapters included a description of the collection methods of unstimulated and stimulated saliva according to the condition of the oral cavity and the usefulness of the analysis of the human saliva as a diagnostic material. RESULTS: Salivary usefulness expanded to monitoring medications, determination of the number of intoxicants, tobacco, exposure to infectious diseases as viral, bacterial and fungal contaminations. Nevertheless, it is recommended for saliva samples to be collected after dental consultation or by trained medical personnel to exclude any risk of local inflammation in oral cavity. CONCLUSIONS: It may seem that salivary diagnostics is necessary and worthy of updating. This last feature undoubt-edly opens up new possibilities in the research for predictive and diagnostic factors in many human conditions. Salivary diagnostics may contribute to a better understanding of the general health status, and thus to more effec-tive treatment methods and improved prognosis.

Bioadhesion on Textured Interfaces in the Human Oral Cavity-An In Situ Study.

Extensive biofilm formation on materials used in restorative dentistry is a common reason for their failure and the development of oral diseases like peri-implantitis or secondary caries. Therefore, novel materials and strategies that result in reduced biofouling capacities are urgently sought. Previous research suggests that surface structures in the range of bacterial cell sizes seem to be a promising approach to modulate bacterial adhesion and biofilm formation. Here we investigated bioadhesion within the oral cavity on a low surface energy material (perfluorpolyether) with different texture types (line-, hole-, pillar-like), feature sizes in a range from 0.7-4.5 µm and graded distances (0.7-130.5 µm). As a model system, the materials were fixed on splints and exposed to the oral cavity. We analyzed the enzymatic activity of amylase and lysozyme, pellicle formation, and bacterial colonization after 8 h intraoral exposure. In opposite to in vitro experiments, these in situ experiments revealed no clear signs of altered bacterial surface colonization regarding structure dimensions and texture types compared to unstructured substrates or natural enamel. In part, there seemed to be a decreasing trend of adherent cells with increasing periodicities and structure sizes, but this pattern was weak and irregular. Pellicle formation took place on all substrates in an unaltered manner. However, pellicle formation was most pronounced within recessed areas thereby partially masking the three-dimensional character of the surfaces. As the natural pellicle layer is obviously the most dominant prerequisite for bacterial adhesion, colonization in the oral environment cannot be easily controlled by structural means.

Development of an Extraction Method of Aflatoxins and Ochratoxin A from Oral, Gastric and Intestinal Phases of Digested Bread by In Vitro Model.

Validated extraction methods from in vitro digestion phases are necessary to obtain a suitable bioaccessibility study of mycotoxins in bakery products. The bakery industry produces bread with different ingredients to enrich the nutritional properties of this product and protect it from fungal growth. This bread can be contaminated by AFB1, AFB2, AFG1, AFG2 and OTA, so an extraction method was developed to analyse these five legislated mycotoxins in digested phases of two types of bread, one with wheat and the other with wheat and also enriched with Cucurbita Maxima Pepo at 20%. The studied "in vitro" digestion model consists of oral, gastric and duodenal phases, each one with different salt solutions and enzymes, that can affect the extraction and most probably the stability of the mycotoxins. The proposed method is a liquid-liquid extraction using ethyl acetate by extract concentration. These analytes and components have an important effect on the matrix effect (MEs) in the analytical equipment, therefore, validating the method and obtaining high sensitivity will be suitable. In the proposed method, the highest MEs were observed in the oral phase of digested pumpkin bread (29 to 15.9 %). Regarding the accuracy, the recoveries were above 83% in the digested duodenal wheat bread and above 76 % in the digested duodenal pumpkin wheat bread. The developed method is a rapid, easy and optimal option to apply to oral, gastric and duodenal phases of digested bread contaminated at a level of established maximum levels by European legislation (RC. 1881/2006) for food.

Oral cavity response to air pollutant exposure and association with pulmonary inflammation and symptoms in asthmatic children.

Exposure to fine particulate matter (PM2.5) and ozone (O3) may lead to inflammation and oxidative damage in the oral cavity, which is hypothesized to contribute to the worsening of airway inflammation and asthma symptoms. In this panel study of 43 asthmatic children aged 5-13 years old, each child had 4 clinic visits with a 2-week interval between two consecutive visits. At each visit, saliva samples were collected and subsequently analyzed for interleukin 6 (IL-6) and eosinophil cationic protein (ECP) as biomarkers of inflammation and malondialdehyde (MDA) as a biomarker of oxidative stress in the oral cavity. At each visit, children were measured for fractional exhaled nitric oxide (FeNO) as a marker of pulmonary inflammation. Asthma symptoms of these children were measured using the Childhood Asthma Control Test (C-ACT). We found that an interquartile range (IQR) increase in 24-h average personal exposure to PM2.5 measured 1 and 2 days prior was associated with increased salivary IL-6 concentration by 3.0% (95%CI: 0.2%-6.0%) and 4.2% (0.7%-8.0%), respectively. However, we did not find a clear association between personal O3 exposure and any of the salivary biomarkers, except for a negative association between salivary MDA and O3 exposure measured 1 day prior. An IQR increase in salivary IL-6 concentration was associated with significantly increased FeNO by 28.8% (4.3%-53.4%). In addition, we found that increasing salivary IL-6 concentrations were associated with decreased individual and total C-ACT scores, indicating the worsening of asthma symptoms. We estimated that 13.2%-22.2% of the associations of PM2.5 exposure measured 1 day prior with FeNO and C-ACT scores were mediated by salivary IL-6. These findings suggest that the induction of inflammation in the oral cavity may have played a role in linking air pollution exposure with the worsening of airway inflammation and asthma symptoms.

The mechanistic pathways of arsenic transport in rice cultivars: Soil to mouth.

Rice cultivars are major conduit of arsenic (As) poisoning to human. We quantified transferability of fifteen rice cultivars representing three groups i.e., high yielding variety (HYV), local aromatic rice (LAR) and hybrid for As from soil to cooked rice and its ingestion led health risk, elucidating the processes of its unloading at five check points. Conducting a field experiment with those cultivars, we sampled roots and shoots at tillering, booting and maturity (with grains), separated the grains into husk, bran and polished rice, cooked it through different methods and analyzed for As. Of the tested groups, As restriction from root to grain followed the order: LARs (94%) > HYVs (88.3%) > hybrids (87.2%). The low As sequestration by LARs was attributed to their higher root biomass (10.20 g hill-1) and Fe-plaque formation (2421 mg kg-1), and lower As transfer coefficients (0.17), and higher As retention in husk and bran (84%). On average, based on calculated four major risk indices, LARs showed 4.7-6.8 folds less As toxicity than HYVs and hybrids. These insights are helpful in advocating some remedies for As toxicity of the tested rice cultivars.

Spatially resolved sampling of the human oral cavity for metabolic profiling.

Here, we present a spatially resolved sampling protocol for the oral human cavity aimed at untargeted metabolomics. We describe the spatial collection of salivary biospecimens, their preparation, and subsequent mass-spectrometry-based untargeted metabolomics analysis. Our protocol avoids complex procedures generally required for gland-specific saliva collection. For the human oral cavity, we provide an easy, flexible, and reproducible solution to comprehensively map the highly heterogeneous environment and elucidate the functionality of salivary components. For complete details on the use and execution of this protocol, please refer to Ciurli et al. (2021).

Bacterial cellulose adhesive composites for oral cavity applications.

Topical approaches to oral diseases require frequent dosing due to limited retention time. A mucoadhesive drug delivery platform with extended soft tissue adhesion capability of up to 7 days is proposed for on-site management of oral wound. Bacterial cellulose (BC) and photoactivated carbene-based bioadhesives (PDz) are combined to yield flexible film platform for interfacing soft tissues in dynamic, wet environments. Structure-activity relationships evaluate UV dose and hydration state with respect to adhesive strength on soft tissue mimics. The bioadhesive composite has an adhesion strength ranging from 7 to 17 kPa and duration exceeding 48 h in wet conditions under sustained shear forces, while other mucoadhesives based on hydrophilic macromolecules exhibit adhesion strength of 0.5-5 kPa and last only a few hours. The work highlights the first evaluation of BC composites for mucoadhesive treatments in the buccal cavity.

Effects of Oral pH Changes on Smoking Desire.

BACKGROUND: Nicotine addiction is associated with nicotine absorption from the buccal mucosa, and it is stated that the main factor that determines nicotine absorption is saliva pH. In the literature, the effects of changes in saliva pH values after eating and drinking on smoking desire in smokers were not questioned. AIM: To show the effect of saliva pH changes on smoking desire. The secondary aim was to show the impact of coffee and water drinking on saliva pH and smoking on oral-dental health (oral hygiene and gingival bleeding). STUDY DESIGN: Case-control study. METHODS: A questionnaire was administered that included "Sociodemographic Data Form" and smoking history and Fagerström Test for Nicotine Dependence (FTND). Oral and dental examinations were performed with mirror sonds and using oral hygiene standard Silness and Leöe plaque index and DMFT Index (Index of Decayed Missing or Filled Teeth). Untreated saliva samples were taken, and baseline saliva flow rate and pH values were measured. To assess pH changes, saliva pH was remeasured after sugar-free instant coffee and water consumption. Smoking desire was evaluated with the Visual Analog Scale (VAS). RESULTS: In this study, 24 (55.8%) females and 19 (44.2%) males were among the 43 smoking and 39 nonsmoking cases. Smoking was significantly associated with poor oral hygiene (in smokers 4.71 (±1.40), in non-smokers 2.30 (±1.59); P < .01). DMFT index was higher in smokers than in non-smokers (in smokers 6.45 (±3.69), in non-smokers 3.87 (±2.67); P < .01). Gingival bleeding was more prevalent in smokers (0.68 (±0.76)) than non-smokers (1.20 (±0.90); P = .009). Salivary flow rates were lower in smokers (in smokers 2.56 (±1.34), in non-smokers 3.00 (±1.22), P = .06). In both groups, pH values increased after coffee consumption and decreased after water; in smokers basal: 6.67 (±0.41), pH coffee: 6.93 (±0.36), pH water: 6.85 (±0.33); in non-smokers pH basal: 6.84 (±0.37), pH coffee: 7.02 (±0.37), pH water: 6.97 (±0.31), P < .01. The VAS values of smokers at basal 4.73 (±3.21); P < 0.01, after coffee consumption 4.91 (±3.08); P < .01, and after water 3.15 (±2.72); P < .01. CONCLUSION: The saliva pH increased after coffee consumption and decreased after drinking water. Besides, VAS values decreased significantly after drinking water. The results suggest that a simple behavior such as drinking water may be used in conjunction with behavioral and cognitive therapies to pursue smoking cessation.

Functionalized Mouth-Conformable Interfaces for pH Evaluation of the Oral Cavity.

Oral health monitoring is highly desired, especially for in home use, however, current methods are not sensitive enough and technically convoluted for this purpose. This paper presents incorporation of bioactive materials and colorimetric chemical sensors into routinely used oral appliances transforming them into bioresponsive, conformable interfaces. Specifically, endodontic paper points and dental floss can be functionalized to locally sense and monitor pH variations within the oral cavity via color changes. Moreover, edible colorimetric indicators are developed and used to make sensing, edible devices in the form factor of candies that can dynamically and visually respond to acidity changes in saliva. These interfaces would enable early detection of caries (e.g., using dental floss and paper points) providing low-cost point of care devices that respond in real-time by detecting pH variations in biological fluids thus bringing monitoring to home settings .

Big eyes can't see microplastics: Feeding selectivity and eco-morphological adaptations in oral cavity affect microplastic uptake in mud-dwelling amphibious mudskipper fish.

Microplastic contamination is a widespread global problem. Plastic pollution in the oceans has received a lot of news coverage, but there is a significant gap in our knowledge about its effect in estuarine areas and a profound regional bias in available information. Here, we estimated the degree of microplastic pollution, its impact on a selected fish, and its function as a vector for heavy metals in the Ulhas River estuary, which is one of the most fragile, polluted, and anthropogenically impacted estuaries in India. Using mudskipper fish, we have also assessed how the feeding guild and ecomorphological adaptations in the feeding apparatus affected the microplastic intake and life history traits of the fish. Sediment, water and fish samples were collected from three sampling localities (S1, S2 and S3) in the Ulhas River estuary and analysed. Findings showed an increase in microplastic abundance from S1 (suburban) to S3 (urban industrial belt) in sediment (96.67-130.0 particles kg-1), water (0.28-0.41 particles L-1) and fish (3.75-6.11 particles per fish). Fragments, followed by pellets and filaments largely contribute to the plastic morphotypes in sediment and water. FTIR analysis revealed polymers of anthropogenic and industrial origin such as polypropylene, Surlyn ionomer, low-density polyethylene, and polyethylene or polybutylene terephthalate. Only filaments were found in the guts of 74% of the mudskippers examined, which may be due to their filter-feeding habit and unique anatomical arrangement of oral structures that effectively filter large microplastic particles. Microplastic abundance showed a strong negative correlation with condition factor, fullness index and hepatosomatic index of fish. SEM-EDS analysis revealed that the microplastic surface topography played an important part in adsorbing heavy metals from a water body containing these contaminants. Results highlight the contamination of vulnerable estuarine habitats, harmful effects on resident biota, and health threats to dependent populations.

Pilot Study to Detect Genes Involved in DNA Damage and Cancer in Humans: Potential Biomarkers of Exposure to E-Cigarette Aerosols.

There is a paucity of data on how gene expression enables identification of individuals who are at risk of exposure to carcinogens from e-cigarette (e-cig) vaping; and how human vaping behaviors modify these exposures. This pilot study aimed to identify genes regulated from acute exposure to e-cig using RT-qPCR. Three subjects (2M and 1F) made three visits to the lab (nTOT = 9 visits); buccal and blood samples were collected before and immediately after scripted vaping 20 puffs (nTOT = 18 samples); vaping topography data were collected in each session. Subjects used their own e-cig containing 50:50 propylene glycol (PG):vegetable glycerine (VG) +3-6 mg/mL nicotine. The tumor suppressor TP53 was significantly upregulated in buccal samples. TP53 expression was puff volume and flow rate dependent in both tissues. In blood, the significant downregulation of N-methylpurine DNA glycosylase (MPG), a base excision repair gene, was consistent across all subjects. In addition to DNA repair pathway, cell cycle and cancer pathways were the most enriched pathways in buccal and blood samples, respectively. This pilot study demonstrates that vaping 20 puffs significantly alters expression of TP53 in human tissues; vaping behavior is an important modifier of this response. A larger study is needed to confirm these relationships.

The solubility of calcium oxalates explains some aspects of their underrepresentation in the oral cavity.

OBJECTIVE: Clarifying the discrepancy between frequently high oxalate concentrations present in saliva, but negligible amounts of calcium oxalate deposits found on oral surfaces. METHODS: Studying the calcium oxalate concentration range that can lead to heterogeneous crystallization in the oral cavity. a) Minimum: calcium oxalate monohydrate (COM) seed crystals were pre-grown ([Ca2+] = [C2O42-] = 1 mM, 30 min, 37 °C), and then re-immersed for ≥6 h to find the solubility equilibrium concentration (no growth, no dissolution). The concentrations tested were [Ca2+]/[C2O42-] : 0.055/0.050, 0.060/0.055, 0.070/0.065 and 0.080/0.075 mM. Supersaturations were calculated via the Debye-Hückel-theory and COM morphologies examined by scanning electron microscopy (SEM). b) Maximum (at the heterogeneous/homogeneous crystallization equilibrium): hydroxyapatite (HA) seed crystals were used to heterogeneously crystallize COM (37 °C, 24 h), using oxalate concentrations between 0.2 and 0.5 mM and calcium concentrations of 0.5 mM. COM-forming oxalate consumption was spectroscopically examined; COM precipitates were investigated by SEM; and HA identity was confirmed by X-ray analysis. RESULTS: Within the concentration range of [Ca2+]/[C2O42-]:0.060/0.055 mM (minimum) and [Ca2+]/[C2O42-]:0.50/0.25 mM (maximum) COM precipitates heterogeneously. In terms of mass, this corresponds to a range of 8.04-36.53 mg/l (daily) or an average of 14.32 mg COM (mimicking e.g. plaque mineralization). Higher concentrations react homogeneously (mimicking precipitation within saliva). CONCLUSION: In vivo, only ∼0.05 % oxalate present in saliva reacts with oral surfaces daily, corresponding to ∼0.0665 µmol/l or ∼9.72 µg COM per day. Calcium-consuming calcium phosphate formation and phosphoproteins such as statherin obviously hinder intraoral COM formation.

Preparation of glass-ionomer cement containing ethanolic Brazilian pepper extract (Schinus terebinthifolius Raddi) fruits: chemical and biological assays.

Plants may contain beneficial or potentially dangerous substances to humans. This study aimed to prepare and evaluate a new drug delivery system based on a glass-ionomer-Brazilian pepper extract composite, to check for its activity against pathogenic microorganisms of the oral cavity, along with its in vitro biocompatibility. The ethanolic Brazilian pepper extract (BPE), the glass-ionomer cement (GIC) and the composite GIC-BPE were characterized by scanning electron microscopy, attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), and thermal analysis. The BPE compounds were identified by UPLC-QTOF-MS/MS. The release profile of flavonoids and the mechanical properties of the GIC-BPE composite were assessed. The flavonoids were released through a linear mechanism governing the diffusion for the first 48 h, as evidenced by the Mt/M∞ relatively to [Formula: see text], at a diffusion coefficient of 1.406 × 10-6 cm2 s-1. The ATR-FTIR analysis indicated that a chemical bond between the GIC and BPE components may have occurred, but the compressive strength of GIC-BPE does not differ significantly from that of this glass-ionomer. The GIC-BPE sample revealed an ample bacterial activity at non-cytotoxic concentrations for the human fibroblast MRC-5 cells. These results suggest that the prepared composite may represent an alternative agent for endodontic treatment.

Identification of potential markers for internal exposure to ambient ozone in oral cavity of healthy adults.

BACKGROUND: Ozone is a highly oxidative gaseous pollutant associated with adverse health outcomes, but markers for internal exposure to ambient ozone are not well-established. METHODS: We aimed to evaluate the feasibility and suitability of the markers in oral microbiome for ambient ozone exposure. Between March and May in 2018, 97 healthy adults were examined on 2 or 3 occasions for oral swab sampling. Hourly concentrations of ambient ozone 1-7 days preceding sampling were collected. Mixed-effect models were fitted to examine the associations between ambient ozone and the diversity and taxon abundances of oral microbiome. Receiver operating characteristic (ROC) curves estimated the accuracies of markers to delineate between samples exposed to different concentrations of ambient ozone. The associations between the makers and lung function were further examined by linear mixed effect models. RESULTS: The averages of daily mean concentrations of ambient ozone (O3-daily), maximum 8-h means (O3-8hmax) and 1-h maximums (O3-1hmax) were respectively 72 µg/m³, 123 µg/m³ and 144 µg/m³. O3-daily was positively associated with α-diversity of oral microbiome, but the exposure-response curves only yielded positive associations in the range of O3-daily from 60 µg/m³ to 75 µg/m³. Results of O3-8hmax and O3-1hmax were consistent with these of O3-daily. With an interquartile range increase in O3-daily at lag04, the abundance of Proteobacteria decreased by 3.1% (95% CI: -4.0%, -2.2%) and Firmicutes increased by 3.3% (95% CI: 2.3%, 4.3%), whilst the Proteobacteria:Firmicutes ratio (P/F) decreased by 0.9 (95% CI: -1.5, -0.4). The areas under ROC curves for Proteobacteria, Firmicutes and P/F were 0.8535, 0.7569 and 0.8929, respectively. Proteobacteria and P/F were associated with forced expiratory volume in the first second and fractional exhaled nitric oxide significantly. CONCLUSION: Ambient ozone disturbs oral microbial homeostasis. Proteobacteria, Firmicutes and their ratio may be potential markers for short-term ambient ozone exposure, and indicators of airway inflammation or lung function decline.

Sedimentary polycyclic aromatic hydrocarbons (PAHs) along the mouth bar of the Yangtze River Estuary: Source, distribution, and potential toxicity.

The source, distribution, and potential toxicity of sedimentary polycyclic aromatic hydrocarbons (PAHs) along the mouth bar of the Yangtze River Estuary were investigated. Total concentrations of 17 PAHs in the study area ranged from 34.94 to 580.26 ng/g (mean value 146.31 ng/g). Results of PMF model revealed that mixed vehicle emissions (38.43%), natural gas combustion (24.98%), biomass combustion (20.76%) and coal combustion (15.83%) were sources of these sedimentary PAHs. The ERL/ERM, TEL/PEL and TEC/PEC values showed that the potential toxicity of PAHs was at low to medium level, but the presence of benzo[a]pyrene (BaP) and benzo[e]pyrene (BeP) requires more attention and research. Sedimentary PAHs pollution level in the three shoals (East Nanhui Shoal, Jiuduansha Shoal and Hengsha Shoal) was higher than that of the two passages (South Passage and North Passage), which demonstrates the possibility of restoration of the adjacent shoals by dredged soils in terms of PAHs pollution.

In vivo solid-phase microextraction swab sampling of environmental pollutants and drugs in human body for nano-electrospray ionization mass spectrometry analysis.

In vivo sampling and sensitive detection of environmental pollutants and drugs in human body play a crucial role in understanding human health. In this study, in vivo solid-phase microextraction (SPME) swab was fabricated using a SPME fiber and a medical cotton swab for noninvasive sampling and extraction of environmental pollutants and drugs in human oral cavity, nasal cavity and on skin surface. After sampling, SPME was coupled with nano-electrospray ionization mass spectrometry (nanoESI-MS) for desorption, ionization, and detection of the extracted analytes. As a result, limit of detection (LOD) and limit of quantification (LOQ) of nicotine in oral fluid were found to be 1.0 pg/mL (S/N ≥ 3) and 4.0 pg/mL (S/N ≥ 10), respectively. Linear dynamic signal responses of nicotine exhibited excellent linearity (R2 = 0.9996) in human oral fluid ranging from 0.1 to 50 ng/mL. The coefficient of variation (CV) values of SPME swab for five measurements from sample vials and human body were 5.1-6.7% and 22.7-32.6%, respectively. Rapid analysis of a single sample could be completed within 10 min. Overall, our results demonstrated that SPME swab-MS is a promising noninvasive method for enhanced detection of analytes in human body.