Assessment of buccal mucosa genotoxicity in insecticide-exposed urban fumigators in Cali, Colombia.

OBJECTIVES: This study aimed to evaluate cytogenetic damage in the buccal mucosa of non-exposed subjects (N = 33) and insecticide-exposed fumigators (N = 31) in the urban area of Cali, Colombia. MATERIAL AND METHODS: Through a questionnaire sociodemographic data, anthropometric measurements, state of health, and lifestyle were collected. Buccal micronucleus cytome (BMCyt) assay was using for evaluate cytogenetic damage. RESULTS: The study showed that all fumigators used adequate personal protective equipment (PPE) and had low alcohol consumption. The authors did not find significant differences in BMCyt biomarkers between the groups (p > 0.05). Multivariate analysis showed a 13% increase in micronucleus (MN) frequency for every year of increasing age (OR = 1.13, p = 0.029), and higher MN with the decrease in daily fruit consumption (OR = 4.71, p = 0.084), without statistical significance. CONCLUSIONS: The results between groups could be related to healthy habits and PPE use among the subjects. Int J Occup Med Environ Health. 2024;37(1):128-37.

DNA damage in workers exposed to pigment grade titanium dioxide (TiO2) and association with biomarkers of oxidative stress and inflammation.

The present study was aimed at investigating DNA damage, micronuclei frequency and meta-nuclear alterations in buccal cells of workers involved in pigment-grade TiO2 production (15 exposed and 20 not-exposed). We also assessed associations of genotoxicity biomarkers with oxidative stress/inflammatory biomarkers in urine and exhaled breath condensate (EBC), as well as possible associations between biomarkers and reported respiratory symptoms. In spite of compliance with TiO2 Occupational Exposure Limits, results showed increased direct/oxidative DNA damage and micronuclei frequency in exposed workers. Genotoxicity parameters were associated with oxidative stress/inflammation biomarkers in urine and EBC, thus confirming that TiO2 exposure can affect the oxidative balance. Workers with higher genotoxic/oxidative stress biomarkers levels reported early respiratory symptoms suggesting that molecular alterations can be predictive of early health dysfunctions. These findings suggest the need to assess early health impairment in health surveillance programs and to address properly safety issues in workplaces where TiO2 is handled.

Processing biological samples from simulated radiological terrorist events using Rapid DNA instruments.

Two commercially available portable Rapid DNA instruments were evaluated for their ability to process 1 µL and 10 µL saliva samples deposited on metal and plastic surfaces and contaminated with surrogates of cesium (Cs)-137, strontium (Sr)-90 and cobalt (Co)-60; radioactive materials potentially released during a nuclear weapon accident or a radiological dispersal device detonation. A comparable success rate was noted for both Rapid DNA instruments when considering the number of complete and balanced DNA profiles, the number of profiles with a minimum of 10 autosomal STR loci (out of 23 [FlexPlex™ 27] or 21 [GlobalFiler™ Express]), and the possibility to search a national DNA database in Canada and the United States. Cobalt had an adverse impact on the quality of the megaplex short tandem repeat (STR) DNA profiles derived on each instrument for two of the three contamination levels tested in this study, i.e., 0.05 M and 0.1 M as reflected by a reduced number of detected alleles and decreased profile peak heights. Strontium exhibited some adverse effect on the Rapid DNA results when used at the highest contamination level (0.1 M) whereas cesium had none. No new artifacts were observed in the Rapid DNA profiles of samples spiked with the non-radiogenic surrogates. Importantly, in the context of a radiological/nuclear (RN) event, the ANDE™ 6C offers the possibility to dispose of all radioactive materials associated with contaminated samples quickly using a chip on which all steps of the Rapid DNA process are performed whereas the RapidHIT™ ID accumulates radioactive materials for many days before disposal. An individual handling 25 samples in a week (5 per day) on the RapidHIT™ ID at a 30.5 cm distance with a 5 min exposure to the radioactive source estimated at every run would exceed the 0.042 µSv/5 min limit with gamma dose rates for Cs at 0.13 mSv and for Co at 3.8 mSv. Beta dose rates calculated for the surrogate isotopes at the three concentrations tested were also above the recommended radiation exposure limit of 1 mSv/yr (0.042 µSv/5 min). Various potential mechanisms of action behind the interference noted for Sr and Co at high concentrations are presented. These elements may play a role in the steps prior to PCR (at the DNA molecule by binding to bases or to phosphate groups), during PCR (at the DNA polymerase as cofactors for catalytic sites), or even during amplified DNA fragment detection (as fluorescence quenchers).

Prenatal exposure to environmental air pollution and psychosocial stress jointly contribute to the epigenetic regulation of the serotonin transporter gene in newborns.

Antenatal exposures to maternal stress and to particulate matter with an aerodynamic diameter of less than 2.5 µm (PM2.5) have been independently associated with developmental outcomes in early infancy and beyond. Knowledge about their joint impact, biological mechanisms of their effects and timing-effects, is still limited. Both PM2.5 and maternal stress exposure during pregnancy might result in altered patterns of DNA methylation in specific stress-related genes, such as the serotonin transporter gene (SLC6A4 DNAm), that might, in turn, influence infant development across several domains, including bio-behavioral, cognitive and socio-emotional domains. Here, we investigated the independent and interactive influence of variations in antenatal exposures to maternal pandemic-related stress (PRS) and PM2.5 on SLC6A4 DNAm levels in newborns. Mother-infant dyads (N = 307) were enrolled at delivery during the COVID-19 pandemic. Infants' methylation status was assessed in 13 CpG sites within the SLC6A4 gene's region (chr17:28562750-28562958) in buccal cells at birth and women retrospectively report on PRS. PM2.5 exposure throughout the entire gestation and at each gestational trimester was estimated using a spatiotemporal model based on residential address. Among several potentially confounding socio-demographic and health-related factors, infant's sex was significantly associated with infants' SLC6A4 DNAm levels, thus hierarchical regression models were adjusted for infant's sex. Higher levels of SLC6A4 DNAm at 6 CpG sites were found in newborns born to mothers reporting higher levels of antenatal PRS and greater PM2.5 exposure across gestation, while adjusting for infant's sex. These effects were especially evident when exposure to elevated PM2.5 occurred during the second trimester of pregnancy. Several important brain processes (e.g., synaptogenesis and myelination) occur during mid-pregnancy, potentially making the second trimester a sensitive time window for the effects of stress-related exposures. Understanding the interplay between environmental and individual-level stressors has important implications for the improvement of mother-infant health during and after the pandemic.

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

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. 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. 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. Intraoral aging adversely affected the physical, mechanical, and morphologic properties of the Invisalign appliance.

DNA Purification from Bloodstains and Buccal Cells/Saliva on FTA® Cards.

FTA® cards enable efficient, long-term storage of blood and buccal cells/saliva samples for future forensic DNA analysis; these are typically collected as known reference samples, as opposed to evidentiary, crime scene samples. Upon contact with the FTA® card, cells are lysed and the DNA is immobilized. Different FTA® cards are available and have been specially formulated based on sample type: bloodstains are added to the traditional FTA® Card, while colorless sources (e.g., buccal cells/saliva) are added to the FTA® Indicating Card. The main difference between these cards is the presence of a pink dye embedded in the indicating cards that becomes white when exposed to colorless fluids, like saliva; this aids in location confirmation of the stain for future sampling. Although DNA can be eluted/extracted from FTA® punches using various methods or, alternatively, direct STR amplification from unpurified punches can be performed, the protocol herein describes a simple purification method for bloodstained punches from FTA® Cards as well as buccal/saliva-stained punches from FTA® Indicating Cards. Following this purification, STR amplification can be performed via the "punch-in" method.

Hydroxyethyl cellulose functionalised with maleimide groups as a new excipient with enhanced mucoadhesive properties.

Hydroxyethylcellulose (HEC) is a non-ionic water-soluble polymer with poor mucoadhesive properties. The mucoadhesive properties of hydroxyethylcellulose can be improved by modifying it through conjugation with molecules containing maleimide groups. Maleimide groups interact with the thiol groups present in cysteine domains in the mucin via Michael addition reaction under physiological conditions to form a strong mucoadhesive bond. This will prolong the residence time of a dosage form containing this modified polymer and drug on mucosal surfaces. In this study HEC was modified by reaction with 4-bromophenyl maleimide in varying molar ratios and the successful synthesis was confirmed using 1H NMR and FTIR spectroscopies. The safety of the newly synthesised polymer derivatives was assessed with in vivo planaria assays and in vitro MTT assay utilising Caco-2 cell line. The synthesized maleimide-functionalised HEC solutions were sprayed onto blank tablets to develop a model dosage form. The physical properties and mucoadhesive behavior of these tablets were evaluated using a tensile test with sheep buccal mucosa. The maleimide-functionalised HEC exhibited superior mucoadhesive properties compared to unmodified HEC.

Characterization of the external exposome and its contribution to the clinical respiratory and early biological effects in children: The PROMESA cohort study protocol.

BACKGROUND: Air pollution contains a mixture of different pollutants from multiple sources. However, the interaction of these pollutants with other environmental exposures, as well as their harmful effects on children under five in tropical countries, is not well known. OBJECTIVE: This study aims to characterize the external exposome (ambient and indoor exposures) and its contribution to clinical respiratory and early biological effects in children. MATERIALS AND METHODS: A cohort study will be conducted on children under five (n = 500) with a one-year follow-up. Enrolled children will be followed monthly (phone call) and at months 6 and 12 (in person) post-enrolment with upper and lower Acute Respiratory Infections (ARI) examinations, asthma development, asthma control, and genotoxic damage. The asthma diagnosis will be pediatric pulmonologist-based and a standardized protocol will be used. Exposure, effect, and susceptibility biomarkers will be measured on buccal cells samples. For environmental exposures PM2.5 will be sampled, and questionnaires, geographic information, dispersion models and Land Use Regression models for PM2.5 and NO2 will be used. Different statistical methods that include Bayesian and machine learning techniques will be used for the ambient and indoor exposures-and outcomes. This study was approved by the ethics committee at Universidad Pontificia Bolivariana. EXPECTED STUDY OUTCOMES/FINDINGS: To estimate i) The toxic effect of particulate matter transcending the approach based on pollutant concentration levels; ii) The risk of developing an upper and lower ARI, based on different exposure windows; iii) A baseline of early biological damage in children under five, and describe its progression after a one-year follow-up; and iv) How physical and chemical PM2.5 characteristics influence toxicity and children's health.

Electronic waste exposure and DNA damage: a systematic review and meta-analysis.

OBJECTIVES: Inappropriate processing and disposal of electronic waste (e-waste) expose workers and surrounding populations to hazardous chemicals, including clastogens and aneugens. Recently, considerable literature has grown around e-waste recycling, associated chemical exposures and intermediate health outcomes, including DNA damage. Micronuclei (MN) frequency has been widely used as a biomarker to investigate DNA damage in human populations exposed to genotoxic agents. We conducted a systematic review of published studies to assess DNA damage in e-waste-exposed populations and performed a meta-analysis to evaluate the association between e-waste exposure and DNA damage. METHODS: This systematic review with meta-analysis was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement checklist. Articles published in English from January 2000 through December 2020 investigating the associations between e-waste exposure and DNA damage were retrieved from the following three major databases: MEDLINE, ProQuest, and Scopus. Studies that reported the use of MN assay as a biomarker of DNA damage were included for meta-analysis. Studies that also reported other DNA damage biomarkers such as chromosomal aberrations, comet assay biomarkers, 8-hydroxy-2'-deoxyguanosine (8-OHdG), telomere length, apoptosis rate were reported using narrative synthesis. RESULTS: A total of 20 publications were included in this review, of which seven studies were within the occupational setting, and the remaining 13 studies were ecological studies. The review found six biomarkers of DNA damage (micronuclei, comets assay parameters (tail length, % tail DNA, tail moment, and olive tail moment), 8-OHdG, telomere length, apoptosis rate and chromosomal aberrations) which were assessed using seven different biological matrices (buccal cells, blood, umbilical cord blood, placenta, urine and semen). Most studies showed elevated levels of DNA damage biomarkers among e-waste exposed populations than in control populations. The most commonly used biomarkers were micronuclei frequency (n=9) in peripheral blood lymphocytes or buccal cells and 8-OHdG (n=7) in urine. The results of the meta-analysis showed that electronic waste recycling has contributed to an increased risk of DNA damage measured using MN frequency with a pooled estimate of the standardized mean difference (SMD) of 2.30 (95% CI: 1.36, 3.24, p<0.001) based on 865 participants. CONCLUSIONS: Taken together, evidence from this systematic review with meta-analysis suggest that occupational and non-occupational exposure to e-waste processing is associated with increased risk of DNA damage measured through MN assay and other types of DNA damage biomarkers. However, more studies from other developing countries in Africa, Latin America, and South Asia are needed to confirm and increase these results' generalizability.

Exfoliated oral mucosa cells as bioindicators of short- and long-term systemic titanium contamination.

BACKGROUND: Humans are exposed to exogenous sources of titanium-containing particles that can enter the body mainly by inhalation, ingestion, or dermal absorption. Given the widespread use of biomaterials in medicine, the surface of a titanium (Ti) biomedical device is a potential endogenous source of Ti ions and/or Ti-containing particles, such as TiO2 micro-(MPs) and nano-particles (NPs), resulting from biotribocorrosion processes. Ti ions or Ti-containing particles may deposit in epithelial cells of the oral mucosa, and the latter may therefore serve as bioindicators of short and long-term systemic Ti contamination. The aim of the present study was to histologically and quantitatively evaluate the presence of Ti traces in cells exfoliated from the oral mucosa as possible bioindicators of systemic contamination with this metal at short and long-term experimental time points METHODS: Thirty Wistar rats were intraperitoneally injected with a suspension of titanium dioxide (TiO2) (0.16 g/100 g body weight of TiO2 in 5 ml of NaCl 0.9%) using 5 nm NPs (Group: TiO2-NP5; n = 10), 45 µm MPs (Group: TiO2-MP45; n = 10), or vehicle alone (Control group; n = 10). At one and six months post-injection, right-cheek mucosa cells were obtained by exfoliative cytology using a cytobrush; they were spray fixed and stained using Safranin or the Papanicolaou technique. The smears were cytologically evaluated (light microscopy) to determine the presence of particulate material, which was also analyzed microchemically (SEM-EDS). Left-cheek mucosa cells were similarly obtained and re-suspended in 5 ml of PBS (pH: 7.2-7.4); the samples corresponding to each group were pooled together and analyzed spectrometrically (ICP-MS) to determine Ti concentration in each of the studied groups. Blood samples were obtained for histological determination of the presence of particulate material on Safranin-stained blood smears and determination of plasma concentration of Ti by ICP-MS RESULTS: Different size and shape metal-like particles were observed inside and outside epithelial cells in TiO2-NP5 and TiO2-MP45 cytological smears at both one and six months post-injection. EDS analysis showed the presence of Ti in the particles. ICP-MS revealed higher Ti concentrations in both TiO2 injected groups compared to the control group. In addition, Ti concentration did not vary with time or particle size. Monocytes containing particles were observed in blood smears of TiO2-exposed animals one- and six-months post-injection. Plasma levels of Ti were significantly higher in TiO2-NP5- and TiO2-MP45- exposed animals than in controls (p < 0.05), and Ti concentration was significantly higher at one month than at six months in both TiO2-exposed groups (p < 0.05). CONCLUSIONS: Cells exfoliated from the oral mucosa could be used as bioindicators of short- and long-term systemic contamination with Ti. Exfoliative cytology could be used as a simple, non-invasive, and inexpensive diagnostic method for monitoring biotribocorrosion of Ti implants and patient clinical follow-up.

Is Curcumin a Safe and Effective Therapeutic in the Treatment against Oral Lichen Planus?

Oral lichen planus (OLP) is a chronic mucocutaneous, immunological disease that occurs more frequently in the buccal mucosa of middle-aged female patients. OLP's standard treatment is topical or systemic corticosteroids. Due to corticosteroids' numerous potential side effects, there is an effort to find an alternative treatment. One alternative treatment is curcumin. Several studies have investigated the effectiveness and safety of curcumin in OLP patients. In this review, we summarized the literature focusing on the effectiveness and safety of curcumin in OLP patients. Our review of clinical trials revealed that either 6000 mg/day curcumin, 80 mg/day nano-curcumin, or 1% curcumin oral gel 6 times/day offered benefits in the treatment of OLP.

Short tandem repeat (STR) instability in the oral mucosa of patients submitted to fixed orthodontic therapy: a limitation of STR profile quality for human identification.

The purpose of this study was to evaluate changes in short tandem repeat (STR) profile quality before and after fixed orthodontic therapy. Samples of oral epithelial cells were obtained from 28 volunteers who had an indication for orthodontic treatment. The samples were collected before and three months after starting orthodontic treatment with fixed appliances. DNA extraction and integrity were evaluated by electrophoresis, and STR profiles were obtained by polymerase chain reaction amplification and STR typing via capillary electrophoresis. DNA electrophoresis showed a higher proportion (7/28, 25%) of DNA degradation in the samples collected after fixed orthodontic treatment compared to those obtained before starting orthodontic therapy (3/28, 11%), however, changes in DNA were not significant (p=0.289). In concordance all STR profiles showed complete genotyping; however, imbalances in the size of heterozygotes and in the signal were detected in 25% of STR profiles after orthodontic therapy. Moreover, STR instability was demonstrated by an increase in stutter bands detected in 60% of the DNA profiles after treatment and a spurious allele of the D195433 marker was found in one sample after treatment. The STR profiles of samples obtained from the oral cavity with orthodontic appliances should be interpreted with caution. STR instability increases the incidence of artifacts that could compromise the quality of the results of tests performed in forensic DNA laboratories.

Liquid Chromatography-Nanoelectrospray Ionization-High-Resolution Tandem Mass Spectrometry Analysis of Apurinic/Apyrimidinic Sites in Oral Cell DNA of Cigarette Smokers, e-Cigarette Users, and Nonsmokers.

Cigarette smoking is an established risk factor for oral cancer. The health effects of e-cigarettes are still under investigation but may disturb oral cavity homeostasis and cause lung and cardiovascular diseases. Carcinogens and toxicants in tobacco products and e-cigarettes may damage DNA, resulting in the formation of apurinic/apyrimidinic (AP) sites and initiation of the carcinogenic process. In this study, we optimized a liquid chromatography-nanoelectrospray ionization-high-resolution tandem mass spectrometry method to analyze AP sites in buccal cell DNA of 35 nonsmokers, 30 smokers, and 30 e-cigarette users. AP sites in e-cigarette users (median 3.3 per 107 nts) were significantly lower than in smokers (median 5.7 per 107 nts) and nonsmokers (median 6.0 per 107 nts). AP sites in smokers were not significantly different from nonsmokers (p > 0.05). The e-cigarette vaporizing solvents propylene glycol and glycerin were tested and did not protect against AP site formation in in vitro control and carcinogen exposed rat liver homogenates. However, propylene glycol may inhibit bacteria in oral cells, resulting in reduced inflammation and related effects, and reduced AP site levels in e-cigarette user DNA. This is the first study to examine AP site formation in e-cigarette users and to evaluate AP sites in human oral cell DNA.

Development and optimization of tibezonium iodide and lignocaine hydrochloride containing novel mucoadhesive buccal tablets: a pharmacokinetic investigation among healthy humans.

OBJECTIVE: It is clinically important to deliver a sustained-release mucoadhesive dosage of local anesthetic and antimicrobial agents for pain control. The current study aimed to develop and evaluate chitosan (CHI) based buccal mucoadhesive delivery for the local release of tibezonium iodide (TBN) and lignocaine hydrochloride (LGN). METHODS: Direct compression technique was employed, aided by other mucoadhesive polymers like hydroxypropylmethylcellulose (HPMC) and sodium alginate (SA) and evaluated for physicochemical and in vivo character. RESULTS: Fourier transform infrared spectral analysis (FTIR), powdered X-ray diffraction (XRPD), and differential scanning calorimetry (DSC) absence of physical interaction between ingredients. The physical parameters complied with USP specifications for all formulations. Optimum swellability (551.9%) was offered from formulation TL15, containing 30% SA. The highest ex vivo mucoadhesive strength (24.79 g) and time (18.39 h) was found with TL8. Formulation TL8 also exhibited maximum in vivo residence time (11.37 h). Almost complete drug release at 6 h was possessed by formulation TL5 (HPMC and CHI, 20% each) for TBN (99.98%) and LGN (99.06%). The optimized formulation TL5 exhibited dosage stability up to 6 months at 75% relative humidity and retained drug contents. TL5 was well tolerated by the volunteers with no inflammation, pain or irritation found. Almost 73% of volunteers reported an increase in salivary secretion. The first-order salivary Cmax of TBN and LGN were found as 16.02 and 7.80 µg/mL within 4 h, respectively. CONCLUSION: Therefore, the sustained release mucoadhesive dosage form of TBN and LGN can be an effective and alternative option to conventional delivery.

Does Panoramic X-ray Induce Cytogenetic Damage to Oral Cells? A Systematic Review With Meta-analysis.

AIM: The aim of this review was to evaluate the scientific literature regarding the cytogenetic damage in oral exfoliated cells of adult patients submitted to panoramic X-ray. MATERIALS AND METHODS: An extensive search of the literature was conducted on PubMed, Scopus and Web of Science databases for all studies published until April 2021 using combinations of the following keywords: "panoramic X-ray," "DNA damage," "genetic damage", "genotoxicity", "mutagenicity", cytotoxicity", "buccal cells", "oral mucosa", "tongue", "gingiva", "micronucleus assay", according to the PRISMA guidelines. All clinical studies in English language were included in the study. A total of 10 studies were identified. RESULTS: As expected, the results regarding the cytogenetic damage induced by panoramic X-ray are conflicting. Some authors have demonstrated that panoramic X-ray induces mutagenesis in oral cells, whereas others did not. After reviewing the 10 studies, two were classified as strong, four were considered moderate, and four were considered weak, according to the quality assessment components of the Effective Public Health Practice Project (EPHPP). Meta-analysis data revealed a negative response related to mutagenicity in oral cells by panoramic X-ray. CONCLUSION: Taken together, this review failed to demonstrate the association between micronucleus frequency and panoramic X-ray.

High-Payload Buccal Delivery System of Amorphous Curcumin-Chitosan Nanoparticle Complex in Hydroxypropyl Methylcellulose and Starch Films.

Oral delivery of curcumin (CUR) has limited effectiveness due to CUR's poor systemic bioavailability caused by its first-pass metabolism and low solubility. Buccal delivery of CUR nanoparticles can address the poor bioavailability issue by virtue of avoidance of first-pass metabolism and solubility enhancement afforded by CUR nanoparticles. Buccal film delivery of drug nanoparticles, nevertheless, has been limited to low drug payload. Herein, we evaluated the feasibilities of three mucoadhesive polysaccharides, i.e., hydroxypropyl methylcellulose (HPMC), starch, and hydroxypropyl starch as buccal films of amorphous CUR-chitosan nanoplex at high CUR payload. Both HPMC and starch films could accommodate high CUR payload without adverse effects on the films' characteristics. Starch films exhibited far superior CUR release profiles at high CUR payload as the faster disintegration time of starch films lowered the precipitation propensity of the highly supersaturated CUR concentration generated by the nanoplex. Compared to unmodified starch, hydroxypropyl starch films exhibited superior CUR release, with sustained release of nearly 100% of the CUR payload in 4 h. Hydroxypropyl starch films also exhibited good payload uniformity, minimal weight/thickness variations, high folding endurance, and good long-term storage stability. The present results established hydroxypropyl starch as the suitable mucoadhesive polysaccharide for high-payload buccal film applications.

Environmental Tobacco Smoke in Occupational Settings: Effect and Susceptibility Biomarkers in Workers From Lisbon Restaurants and Bars.

Environmental tobacco smoke (ETS) has been recognized as a major health hazard by environmental and public health authorities worldwide. In Portugal, smoke-free laws are in force for some years, banning smoking in most indoor public spaces. However, in hospitality venues such as restaurants and bars, owners can still choose between a total smoke-free policy or a partial smoking restriction with designated smoking areas, if adequate reinforced ventilation systems are implemented. Despite that, a previous study showed that workers remained continuously exposed to higher ETS pollution in Lisbon restaurants and bars where smoking was still allowed, comparatively to total smoke-free venues. This was assessed by measurements of indoor PM2.5 and urinary cotinine, a biomarkers of tobacco smoke exposure, demonstrating that partial smoking restrictions do not effectively protect workers from ETS. The aim of the present work was to characterize effect and susceptibility biomarkers in non-smokers from those hospitality venues occupationally exposed to ETS comparatively to non-exposed ones. A group of smokers was also included for comparison. The sister chromatid exchange (SCE), micronucleus (MN) and comet assays in whole peripheral blood lymphocytes (PBLs) and the micronucleus assay in exfoliated buccal cells, were used as biomarkers of genotoxicity. Furthermore, a comet assay after ex vivo challenge of leukocytes with an alkylating agent, ethyl methanesulfonate (EMS), was used to analyze the repair capacity of those cells. Genetic polymorphisms in genes associated with metabolism and DNA repair were also included. The results showed no clear association between occupational exposure to ETS and the induction of genotoxicity. Interestingly, the leukocytes from non-smoking ETS-exposed individuals displayed lower DNA damage levels in response to the ex vivo EMS challenge, in comparison to those from non-exposed workers, suggesting a possible adaptive response. The contribution of individual susceptibility to the effect biomarkers studied was unclear, deserving further investigation.

IL-6, sTNF-R2, and CRP in the context of sleep, circadian preference, and health in adolescents with eveningness chronotype: Cross-sectional and longitudinal treatment effects.

BACKGROUND: Inflammation-related processes have emerged as a biological pathway related to adolescent development. This study examined cross-sectional and longitudinal associations of baseline inflammatory markers with sleep, circadian preference, and health at baseline and following treatment. METHODS: Participants included 165 adolescents (58.2% female, mean age 14.7 years, 42.4% taking medication) "at-risk" in at least one domain (emotional, cognitive, behavioral, social, and physical health) who received a sleep-based intervention. Self-reported eveningness as well as total sleep time (TST) and bedtime from sleep diary were assessed at baseline and following treatment. Baseline soluble tumor necrosis factor receptor-2 (sTNF-R2) and interleukin (IL)-6 were assayed from oral mucosal transudate. Baseline C-reactive protein (CRP) was assayed from saliva. RESULTS: At baseline, shorter TST was associated with more emotional risk among adolescents with higher CRP (b = -0.014, p = 0.007). Greater eveningness was related to more behavioral risk in the context of lower IL-6 (b = -0.142, p = 0.005). Following treatment, lower baseline IL-6 was associated with reduced behavioral risk (Χ2 = 8.06, p = 0.045) and lower baseline CRP was related to reduced physical health risk (Χ2 = 9.34, p = 0.025). Baseline inflammatory markers were not significantly associated with sleep, circadian, or other health domain change following treatment. CONCLUSIONS: There was cross-sectional evidence that sleep and circadian dysfunction differentially relate to emotional and behavioral health risk for high and low levels of inflammatory markers. Longitudinal analyses indicated that lower levels of baseline inflammatory markers may be related to better treatment response to a sleep-based intervention.

Extraction and electrochemical detection for quantification of trace-level DNA.

A novel strategy was developed to extract, detect, and quantify trace-level DNA. For the extraction step, a composite of methylene blue (MB), poly(acrylic acid) (PAA), and modified iron oxide magnetic nanoparticles (IOMNPs) (PAA/IOMNPs) was used to adsorb DNA from the sample. MB-PAA/IOMNPs with adsorbed DNA were then separated from the solution with an external magnet and MB-DNA was eluted from PAA/IOMNPs with acetic acid. In the detection step, MB-DNA was adsorbed on the surface of 3-aminopropyltriethoxysilane (APTES)-modified glassy carbon electrode via electrostatic force. DNA was quantified by measuring the oxidation peak of MB at a potential -0.13 V vs. Ag/AgCl using differential pulse voltammetry. Under the optimal experimental conditions, the DNA sensor showed linear ranges from 0.001 to 0.005 pg µL-1, 0.005 to 0.070 pg µL-1, and 0.070 to 0.400 pg µL-1 and a limit of detection of 0.87 fg µL-1. The proposed sensor detected trace DNA in real samples with recoveries that ranged from 80.4 to 90.4%.

Associations of fine particulate matter and its constituents with airway inflammation, lung function, and buccal mucosa microbiota in children.

BACKGROUND: Previous studies have suggested acute effects of ambient fine particulate matter (PM2.5) air pollution on respiratory health among children, but evidence for PM2.5 constituents and respiratory health were still limited. OBJECTIVES: To investigate associations of short-term exposure to PM2.5 and its constituents with airway inflammation, lung function, and airway microbiota in children. METHODS: We conducted a longitudinal panel study with 3 repeated health measurements among 62 children in Shanghai, China from November 2018 to June 2019. Respiratory health was measured by fractional exhaled nitric oxide (FeNO), saliva tumor necrosis factor-α (TNF-α), lung function (forced vital capacity and forced exhaled volume in 1 s), and microbiota diversity in buccal mucosa samples. Based on the linear mixed-effect models, we applied the single-constituent models and the constituent-PM2.5 adjustment models to examine the associations between PM2.5 constituents and health outcomes. RESULT: Short-term exposure to PM2.5 was associated with higher TNF-α, FeNO levels and reduced lung function. Among all constituents, organic carbon, elemental carbon, NO3- and NH4+ had the consistent and strongest associations with airway inflammation biomarkers and lung function parameters, followed by metallic elements. We also found short-term PM2.5 exposure was associated with decreased diversity in buccal mucosa bacterial community and two bacterial phyla, Fusobacteria and Proteobacteria, were identified as differential microbes with PM2.5 exposure. CONCLUSION: Short-term exposure to PM2.5 may impair children's respiratory health represented by higher airway inflammation, lower lung function and altered buccal mucosa microbial colonization. Organic carbon, elemental carbon, NO3- and NH4+ may dominate these effects.