Methylglyoxal-induced neurotoxic effects in primary neuronal-like cells transdifferentiated from human mesenchymal stem cells: Impact of low concentrations.

In the last decades, advanced glycation end-products (AGEs) have aroused the interest of the scientific community due to the increasing evidence of their involvement in many pathophysiological processes including various neurological disorders and cognitive decline age related. Methylglyoxal (MG) is one of the reactive dicarbonyl precursors of AGEs, mainly generated as a by-product of glycolysis, whose accumulation induces neurotoxicity. In our study, MG cytotoxicity was evaluated employing a human stem cell-derived model, namely, neuron-like cells (hNLCs) transdifferentiated from mesenchymal stem/stromal cells, which served as a source of human based species-specific "healthy" cells. MG increased ROS production and induced the first characteristic apoptotic hallmarks already at low concentrations (≥10 µM), decreased the cell growth (≥5-10 µM) and viability (≥25 µM), altered Glo-1 and Glo-2 enzymes (≥25 µM), and markedly affected the neuronal markers MAP-2 and NSE causing their loss at low MG concentrations (≥10 µM). Morphological alterations started at 100 µM, followed by even more marked effects and cell death after few hours (5 h) from 200 µM MG addition. Substantially, most effects occurred as low as 10 µM, concentration much lower than that reported from previous observations using different in vitro cell-based models (e.g., human neuroblastoma cell lines, primary animal cells, and human iPSCs). Remarkably, this low effective concentration approaches the level range measured in biological samples of pathological subjects. The use of a suitable cellular model, that is, human primary neurons, can provide an additional valuable tool, mimicking better the physiological and biochemical properties of brain cells, in order to evaluate the mechanistic basis of molecular and cellular alterations in CNS.

Microwave-Assisted and Conventional Extractions of Volatile Compounds from Rosa x damascena Mill. Fresh Petals for Cosmetic Applications.

Rosa x damascena Mill. essential oil is mainly used in the cosmetics and perfumery industry, but it also finds application in the food industry as a flavoring agent. The chemical composition of essential oils is affected by environment, soil, harvesting technique, storage condition, and extraction methods. Nowadays, the study and design of greener, more efficient, and sustainable extractive procedures is the main and strategic focus in the chemical research and development of botanical derivatives, especially as regards fragrances and essential oils. Several technologies are available, and the best method to use depends on the desired chemicals, but conventional extractive processes are often laborious and time-consuming, involve large amounts of solvents, and may cause the partial loss of volatiles, affecting the quality of the final product. In the last decade, microwave irradiation has been successfully applied to classical techniques, often improving the general extractive efficiency and extract quality. In the present paper, as a preliminary analytical screening approach, two microwave-mediated techniques, Solvent-Free Microwave Extraction (SFME) and Microwave Hydrodiffusion and Gravity (MHG), and two conventional procedures, Hydrodistillation (HD) and Steam Distillation (SD), were applied and compared for the extraction of volatile compounds from R. x damascena fresh petals to highlight differences and advantages of the selected procedure and of the obtained extracts useful in a cosmetic context as fragrances or active ingredients. The chemical composition of the extracts was investigated by GC-MS and GC-FID. Sixty-one components, distributed in the four techniques, were identified. SD and HD are dominated by oxygenated terpenes (59.01% and 50.06%, respectively), while MHG and SFME extracts are dominated by alcohols (61.67% and 46.81%, respectively). A relevant variability in the composition of the extracts relating to the extraction techniques used was observed. To point out the correlation between the process and composition of the obtained natural products, principal component analysis (PCA) of the data extracted from GC-FID was used. Taking into account a cosmetic application, SFME shows several advantages when compared with the other procedures. The extract (obtained in a significantly higher amount) contains a meaningful lower level of potential fragrance allergenic compounds and quite a double amount of benzyl alcohol and 2-phenyl ethanol that can also enhance the preservative action in personal care products.

Validation of cleaning procedures used in an Italian Hospital Pharmacy for antineoplastic drug decontamination: a new tool for industrial hygiene.

BACKGROUND: Current Italian regulations and procedures for surface decontamination of antineoplastic drugs (ADs) are not clear. Therefore, most hospital pharmacies follow internal procedures as an interpretation of the recommended handling guidelines. OBJECTIVES: Our study compared 7 different cleaning procedures after controlled contamination of the work surface of a biological safety cabinet workbench in an Italian hospital oncology pharmacy (HOP) to determine which of them is more efficient and practical. Moreover, in order to approximate operative routine and improve risk awareness, cleaning procedures were carried out by the personnel that usually operate in the HOP. METHODS: Measured quantities, i.e. a drop (100 µL) of 5-FluoroUracil, IPhosfamide, CycloPhosphamide and Gemcitabine, were deposited on the work surface within precisely delimited areas. Following the wipe-test analysis using UPLC-MS/MS, the cleaning efficacy was calculated based on the ratio of the residual concentration of the AD, after the cleaning procedure, to the concentration of each AD before the procedure. RESULTS: Tested cleaning procedures were: 1) Hypo-Chlor®, hot water and Farmecol70®; 2) Hypo-Chlor® and hot water; 3) Farmecol70®; 4) Surfa'Safe SH® and hot water; 5) Amuchina® 10%, hot water and Farmecol70®; 6) Incidin® Oxyfoam and hot water; 7) liquid Marseille soap, hot water and Farmecol70®. Within the studied HOP, the Marseille soap was evaluated to be the optimal choice due to its efficacy, low cost, and the very short contact time needed before rinsing. DISCUSSION: The application of the protocol for procedure validation suggested here could be used in every HOP as a reliable industrial hygiene tool to demonstrate the validity of the chosen cleaning procedure.

[Risk assessment for food preparation, cooking and service]. / Rischi da lavoro nel settore della ristorazione.

The restaurant and food preparation, cooking and distribution sector includes hotels, restaurants, catering, fast food, ecc. The restaurant and food preparation, cooking and distribution sector form a significant part of the Italian economy; they provide employment for a large number of people, both direct employees as well as part-time and contract staff. In this sector there are many hazards that can lead to a broad range of injuries and/or diseases to the workers. For the safety these hazards principally are slick floors, open flames, high temperature cooking surfaces, steam, knives and other cutting instruments and machineries. For the health: cleaning and disinfecting chemicals substances, cooking fumes and vapors, biological agents, heavy loads handling, thermal comfort, ecc. The paper presents an overview of the hazards in the sector and then make a focus on chemical risks identification and assessment to evaluate the workers' exposure (by skin adsorption and inhalation).

Evaluation of the Biological Activity of Manna Exudate, from Fraxinus ornus L., and Its Potential Use as Hydrogel Formulation in Dermatology and Cosmetology.

Manna, a well-known herbal drug has multiple traditional and pharmaceutical uses and the entire composition, sugar derivatives and polyphenols, gives rise to a very interesting bioactive complex with versatile therapeutic and benefic properties such as antioxidant and anti-inflammatory activities. The aim of this research was to investigate a F. ornus manna extract loaded in a pectin hydrogel as a synergic vehicle to evaluate the potential use of the complex for cosmetic and dermatological applications. In particular, the study set out to disclose manna properties as a wound healing agent with antimicrobial and reparative activity on infected tissues. Moreover, considering the correlation between antioxidant activity and antiaging potential, the extract was investigated in regard to the anti-elastase activity and skin whitening potential. The total phenolic content of each extract was also determined and a safe profile by in vitro cytotoxicity studies was verified. The hydrogel complex, containing the manna extract and pectin as the gelling agent, exhibited suitable properties in terms of pH (from 5.50 to 6.80), rheological behavior and ability of preserving the antioxidant activity of the manna exudate (around 10%). All the peculiarities that make the pectin hydrogels ideal systems for skin disease, as wound dressings and for antiaging cosmetic formulations.

Combined Ferritin Nanocarriers with ICG for Effective Phototherapy Against Breast Cancer.

Introduction: Photodynamic Therapy (PDT) is a promising, minimally invasive treatment for cancer with high immunostimulatory potential, no reported drug resistance, and reduced side effects. Indocyanine Green (ICG) has been used as a photosensitizer (PS) for PDT, although its poor stability and low tumor-target specificity strongly limit its efficacy. To overcome these limitations, ICG can be formulated as a tumor-targeting nanoparticle (NP). Methods: We nanoformulated ICG into recombinant heavy-ferritin nanocages (HFn-ICG). HFn has a specific interaction with transferrin receptor 1 (TfR1), which is overexpressed in most tumors, thus increasing HFn tumor tropism. First, we tested the properties of HFn-ICG as a PS upon irradiation with a continuous-wave diode laser. Then, we evaluated PDT efficacy in two breast cancer (BC) cell lines with different TfR1 expression levels. Finally, we measured the levels of intracellular endogenous heavy ferritin (H-Fn) after PDT treatment. In fact, it is known that cells undergoing ROS-induced autophagy, as in PDT, tend to increase their ferritin levels as a defence mechanism. By measuring intracellular H-Fn, we verified whether this interplay between internalized HFn and endogenous H-Fn could be used to maximize HFn uptake and PDT efficacy. Results: We previously demonstrated that HFn-ICG stabilized ICG molecules and increased their delivery to the target site in vitro and in vivo for fluorescence guided surgery. Here, with the aim of using HFn-ICG for PDT, we showed that HFn-ICG improved treatment efficacy in BC cells, depending on their TfR1 expression. Our data revealed that endogenous H-Fn levels were increased after PDT treatment, suggesting that this defence reaction against oxidative stress could be used to enhance HFn-ICG uptake in cells, increasing treatment efficacy. Conclusion: The strong PDT efficacy and peculiar Trojan horse-like mechanism, that we revealed for the first time in literature, confirmed the promising application of HFn-ICG in PDT.

[Evolution of technology and occupational exposures in petrochemical industry and in petroleum refining]. / Evoluzioni della tecnologia e delle esposizioni professionali nell'industria petrolchimica e nella raffinazione del petrolio.

The industry of oil refining and petrochemical play an important role in terms of number of employees in the Italian production. Often the terms "petroleum refining" and "petrochemical" are used interchangeably to define processes that occur in complex plants, which grow outdoors on large surfaces and a visual impact is not irrelevant. In reality, the two areas involve potential exposure to different chemical agents, related to raw materials processed and the specific products. The petrochemical uses as raw materials, the oil fractions, obtained by distillation in the refinery, or natural gas; petrochemical products are, usually, single compounds with a specific degree of purity, used as basic raw materials for the entire industry of organic chemistry, from the production of plastics to pharmaceuticals. The oil refining, that is the topic of this paper, processes mainly oil to obtain mixtures of hydrocarbon compounds, the products of which are specified on the basis of aptitude for use. For example gasolines, are obtained by mixing of fractions of the first distillation, reforming products, antiknock. The paper illustrates, necessarily broadly due to the complexity of the productive sectors, the technological and organizational changes that have led to a significant reduction of occupational exposure to chemical agents, the results of environmental monitoring carried out in some refineries both during routine conditions that during scheduled maintenance activities with plant shutdown and a store of petroleum products. The chemical agents measured are typical for presence, physico-chemical properties and toxicological characteristics of the manufacturing processes of petroleum products like benzene, toluene, xylenes, ethyl benzene, n-hexane, Volatile Hydrocarbons belonging to gasoline, kerosene, diesel fuel. Data related to both personal sampling and fixed positions.

Accurate low-dose exposure assessment of benzene and monoaromatic compounds by diffusive sampling: sampling and analytical method validation according to ISO 23320 for radiello® samplers packed with activated charcoal.

The research study aimed at providing an accurate low-dose benzene exposure assessment method, by validating diffusive monitoring techniques for benzene personal exposure measurements at workplaces where benzene concentrations are expected in the low ppb range, such as in the present-day chemical, petrochemical, foundry, and pharmaceutical industry. The project was aimed at addressing the need for a robust and fully validated method to perform personal exposure measurements considering that the occupational exposure limit value for benzene is going to be significantly lowered in the next few years. Diffusive sampling offers a reliable alternative to pumped sampling methods, intrinsic safety in potentially explosive atmospheres, lightness, and ease of use. In this study, the radiello® diffusive sampler, with the packed activated charcoal RAD130 adsorbing substrate [suitable for solvent desorption and analysis by high-resolution gas chromatography-flame ionization detection (HRGC-FID)], was used. The experiments have been conducted following the ISO 23320 standard in the range from 0.005 to 0.1 ppm (16 to 320 µg/m3), yielding a full validation of the sampling and analytical method. The sampler performances have fulfilled all requisites of the ISO 23320 standard, in particular: bias due to the selection of a non-ideal sorbent is lower than 10% (no significant back diffusion of benzene due to concentration change in the atmosphere); bias due to storage of samples for up to 2 months is lower than 10%; nominal uptake rate for benzene on RAD130 is 74.65 mL/min; and expanded uncertainty of the sampling and analytical method is 20.6%. The sampling and analytical method is therefore fit-for-purpose for the personal exposure measurements aimed at testing compliance with occupational exposure limit values for benzene. The method is also fit for short-duration exposure monitoring related to specific tasks, and other volatile organic compounds, usually found in the same workplaces, such as aliphatic and aromatic hydrocarbons and some oxygenated compounds, have also been studied. In particular, n-hexane and isopropyl benzene, whose classification is currently under revision, can be efficiently monitored by this technique.

Deciphering the Role of H-Ferritin Nanocages in Improving Tumor-Targeted Delivery of Indocyanine Green: Combined Analysis of Murine Tissue Homogenates with UHPLC-MS/MS and Fluorescence.

We investigated the relevance of encapsulation in H-ferritin nanocages (HFn) in determining an improved tumor-targeted delivery of indocyanine green (ICG). Since from previous experiments, the administration of HFn loaded with ICG (HFn-ICG) resulted in an increased fluorescence signal of ICG, our aim was to uncover if the nanoformulation could have a major role in driving a specific targeting of the dye to the tumor or rather a protective action on ICG's fluorescence. Here, we took advantage of a combined analysis involving ultrahigh performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) on murine tissue homogenates matched with fluorescence intensities analysis detected by ex vivo optical imaging. The quantification of ICG content performed on different organs over time combined with the fluorescent signal detection confirmed the superior delivery of ICG thanks to the nanoformulation. Our results showed that HFn-ICG drives a real accumulation at the tumor instead of only having a role in the preservation of ICG's fluorescence, further supporting its use as a delivery system of ICG for fluorescence-guided surgery applications in oncology.

[Exposure to leather dusts and organic solvents--results of the PPTP-shoe study]. / Esposizione a polveri di cuoio e solventi organici--I risultati dello studio PPTP-calzatura.

In the shoe industry leather dusts and organic solvents present in glues can be identified as a significant chemical risks. To assess the level of occupational exposure a sector study was conducted on small to medium size companies: in 9 were measured the respirable and inhalable dust concentrations and in 13 the solvents. The measurements were performed using personal samplers. The results confirmed the assumed Similar Exposure Group (SEG). The average concentrations of dust were well below the TLV-TWA, the Mixture Index for the solvents is exceeded in 9 out of 67 cases, the "critical" solvent has proven to be cyclohexane.

Exposure to Antineoplastic Drugs in Occupational Settings: A Systematic Review of Biological Monitoring Data.

The high toxicity of antineoplastic drugs (ADs) makes them dangerous not only for patients, but also for exposed workers. Therefore, the aim of this review was to provide an updated overview of the biological monitoring of occupational AD exposure in order to extrapolate information useful to improve risk assessment and management strategies in workplaces. Several studies demonstrated that remarkable portions of healthcare workers may have traces of these substances or their metabolites in biological fluids, although with some conflicting results. Nurses, directly engaged in AD handling, were the occupational category at higher risk of contamination, although, in some cases, personnel not involved in AD-related tasks also showed quantifiable internal doses. Overall, further research carried out on greater sample sizes appears necessary to gain deeper insight into the variability retrieved in the reported results. This may be important to understand the impact of the extent of ADs use, different handling, procedures, and cleaning practices, spill occurrence, training of the workforce, as well as the adoption of adequate collective and personal protective equipment in affecting the occupational exposure levels. This may support the achievement of the greatest clinical efficiency of such therapies while assuring the health and safety of involved workers.

Particle measurements of metal additive manufacturing to assess working occupational exposures: a comparative analysis of selective laser melting, laser metal deposition and hybrid laser metal deposition.

This paper presents the results of a measurement campaign for assessing the release of particles and the potential exposure of workers in metal additive manufacturing. The monitoring deals with three environments, i.e., two academic laboratories and one production site, while printing different metallic alloys for chemical composition and size. The monitored devices implement different metal 3D printing processes, named Selective Laser Melting, Laser Metal Deposition and Hybrid Laser Metal Deposition, providing a wide overview of the current laser-based Additive Manufacturing technologies. Despite showing the generation of metal powders during the printing processes, the usual measurements based on gravimetric analysis did not highlight concentrations higher than the international exposure limits for the selected metals (i.e., chromium, cobalt, iron, nickel, and copper). Additional data, collected through a cascade impactor and particle counter coupled with the achievements from previous measurements reported in literature, indicate that during the printing operations, fine and ultrafine metal particles might be generated. Finally, the authors introduced a preliminary characterisation of the particles released during the different phases of the investigated AM processes (powder charging, printing, part cleaning and support removal), highlighting how the different operations may affect the particle size and concentration.

Occupational Exposure Assessment to Antineoplastic Drugs in Nine Italian Hospital Centers over a 5-Year Survey Program.

In the present study, surface contamination where antineoplastic drugs (ADs) are present was investigated, as occupational exposure risk is still an open debate. Despite recommendations and safety standard procedures being in place in health care settings, quantifiable levels of ADs are being reported in the recent literature. Thus, a survey monitoring program was conducted over five years (2016-2021) in nine Italian hospitals. The repeated surveys produced 8288 data points that have been grouped according to the main hospital settings, such as pharmacy areas and patient care units. Based on the most often prepared ADs, the investigated drugs were cyclophosphamide (CP), gemcitabine (GEM), 5-fluorouracil (5-FU), and platinum compounds (Pt). Patient care units had a frequency of positive wipe samples (59%) higher than pharmacies (44%). Conversely, pharmacies had a frequency of positive pad samples higher (24%) than patient care units (10%). Moreover, by statistical analysis, pad samples had a significantly higher risk of contamination in pharmacy areas than in patient care units. In this study, the 75th and the 90th percentiles of the contamination levels were obtained. The 90th percentile was chosen to describe a suitable benchmark that compares results obtained by the present research with those previously reported in the literature. Based upon surface contamination loads, our data showed that 5-FU had the highest concentration values, but the lowest frequency of positive samples. In pharmacy areas, the 90th percentile of 5-FU data distribution was less than 0.346 ng/cm2 and less than 0.443 ng/cm2 in patient care units. AD levels are higher than those reported for health care settings in other European countries yet trends of contamination in Italy have shown to decrease over time.

Modelling infrared radiation exposure by black body-like sources.

In this work, a method previously proposed in the literature (Sisto R, Pinto I, Stacchini N et al. Infrared radiation exposure in traditional glass factories. AIHAJ 2000; 61: 5-10) to evaluate the exposure to infrared (IR) radiation when the source can be approximated as a black body is implemented in a mathematical code developed in Matlab. Some practical situations are discussed. A comparison between the results obtained by a spectroradiometric technique and that obtained by using a broadband radiometer and the modelling of the source is shown. The IR radiation exposure evaluations in a cement industry and in a steel forge are shown and compared to the exposure limit values.

[Risk assessment of chemical agents]. / La valutazione del rischio da agenti chimici.

The risk assessment of chemical agents is a well known and applied process carried out by Industrial Hygienists and Occupational Physicians based on exposure evaluation. The application of REACH (CE 1907/2006), CLP (CE 1272/2008) and SDS (UE 453/2010) introduces some changes and instruments to carry out the occupational exposure assessment, like new classification of substances, Exposure Scenario, suggested control measures that the Industrial Hygienist and the Occupational Physician must evaluate. If there is not a similar Exposure Scenario to apply a new risk assessment must carried out also by recommended software (ECETOC Targeted Risk Assessment; Easy to use workplace EMKG; Stoffenmanager). Looking at the relevance of the control measures and evaluation of Exposure Scenario we report the flowchart of risk assessment and management by the Method of Organisational Congruencies carried out with the Prevention and Protection Service and Occupational Physician Office of the Health Service of the Azienda Provinciale of Trento.

[The Maugeri Stress Index: a questionnaire to assess work-related psychological stress]. / Il Maugeri Stress Index questionnaire per la valutazione dello stress lavoro correlato.

INTRODUCTION: The European directives concerning the evaluation of work-related stress were absorbed into Italian law by means of Legislative Decree No. 81 of 9 April 2008. AIMS: To develop a new questionnaire to assess the impact of work-related psychological distress and to validate it by testing its factorial structure, its content, its construct and discriminant validity. METHODS: After critically reviewing the literature, we generated an initial item set to identify the items to be used in a preliminary version of the questionnaire, and then used a focus group to test the comprehensibility of the items. The questionnaire was administered to 329 subjects working in state and private organisation and a small sample of 29 subjects complaining of vexation at work. RESULTS: The Maugeri Stress Index (MSI) is reliable (Cronbach alpha: 0.93). Factorial analysis indicated five factors: Well-being, Adaptation, Support, Irritability and Avoidance. The total and subscale scores were significantly different when comparing subjects with and without vexation at work. CONCLUSION: The MSI has a multi-factorial structure, good internal reliability and sufficient discriminant power.

Chemical Composition of Essential Oil from Flowers of Five Fragrant Dendrobium (Orchidaceae).

A detailed chemical composition of Dendrobium essential oil has been only reported for a few main species. This article is the first to evaluate the essential oil composition, obtained by steam distillation, of five Indian Dendrobium species: Dendrobium chrysotoxum Lindl., Dendrobium harveyanum Rchb.f., and Dendrobium wardianum R.Warner (section Dendrobium), Dendrobium amabile (Lour.) O'Brien, and Dendrobium chrysanthum Wall. ex Lindl. (section Densiflora). We investigate fresh flower essential oil obtained by steam distillation, by GC/FID and GC/MS. Several compounds are identified, with a peculiar distribution in the species: Saturated hydrocarbons (range 2.19-80.20%), organic acids (range 0.45-46.80%), esters (range 1.03-49.33%), and alcohols (range 0.12-22.81%). Organic acids are detected in higher concentrations in D. chrysantum, D. wardianum, and D. harveyanum (46.80%, 26.89%, and 7.84%, respectively). This class is represented by palmitic acid (13.52%, 5.76, and 7.52%) linoleic acid (D. wardianum 17.54%), and (Z)-11-hexadecenoic acid (D. chrysantum 29.22%). Esters are detected especially in species from section Dendrobium, with ethyl linolenate, methyl linoleate, ethyl oleate, and ethyl palmitate as the most abundant compounds. Alcohols are present in higher concentrations in D. chrysantum (2.4-di-tert-butylphenol, 22.81%), D. chrysotoxum (1-octanol, and 2-phenylethanol, 2.80% and 2.36%), and D. wardianum (2-phenylethanol, 4.65%). Coumarin (95.59%) is the dominant compound in D. amabile (section Densiflora) and detected in lower concentrations (range 0.19-0.54%) in other samples. These volatile compounds may represent a particular feature of these plant species, playing a critical role in interacting with pollinators.

Oxidative stress induction in woodworkers occupationally exposed to wood dust and formaldehyde.

BACKGROUND: Many workers are exposed to wood dust (WD) and formaldehyde (FA), whose carcinogenic activity is supposed to be oxidative stress-mediated. This study aims to assess to what extent the occupational exposure to WD and FA, albeit within regulatory limits, could result in OS induction in a woodworkers' population. METHODS: The sample population consisted of 127 woodworkers from 4 factories and 111 unexposed controls. Individual exposure was assessed by personal air-samplers. Each participant enrolled in the study filled out a questionnaire and provided a urinary sample to quantify OS biomarkers, namely 15-F2t-IsoProstane (15-F2t-IsoP) and 7,8-dihydro-8-oxo-2'-deoxyguanosine (8-oxo-dGuo). The main confounding factor for OS, i.e. tobacco smoking exposure, was assessed by measuring cotinine in urine samples. RESULTS: Woodworkers were exposed to significantly higher amounts of WD and FA as compared to controls (p < 0.001). Among OS biomarkers, 15-F2t-IsoP showed statistically significant higher values in woodworkers compared to controls (p = 0.004). A significant, positive correlation was observed between 15-F2t-IsoP and 8-oxo-dGuo (p = 0.005), cotinine (p = 0.05), FA (p < 0.001) and WD (p = 0.01); 8-oxo-dGuo was significantly correlated with cotinine (p = 0.001) and WD (p = 0.004). In addition, WD and FA were significantly correlated each other (p < 0.001). CONCLUSIONS: The study confirms that WD and FA may induce OS in woodworkers, and highlights that even the compliance with occupational exposure limits can result in measurable biological outcomes.

Development and Validation of a Bioanalytical UHPLC-MS/MS Method Applied to Murine Liver Tissue for the Determination of Indocyanine Green Loaded in H-Ferritin Nanoparticles.

Indocyanine green (ICG) is one of the most commonly used fluorophores in near-infrared fluorescence-guided techniques. However, the molecule is prone to form aggregates in saline solution with a limited photostability and a moderate fluorescence yield. ICG was thus formulated using protein-based nanoparticles of H-ferritin (HFn) in order to generate a new nanostructure, HFn-ICG. In this study, an ultrahigh performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) system was employed to develop and validate the quantitative analysis of ICG in liver tissue samples from HFn-ICG-treated mice. To precipitate HFn, cold acetone in acidic solution at pH 5.0 was used. The processed liver samples were injected into the UHPLC-MS/MS system for analysis using the positive electrospray ionization mode. Chromatographic separation was achieved on a Waters Acquity UPLC® HSS T3 Column (1.8 µm, 2.1 × 100 mm) with 0.1% formic acid and acetonitrile as the mobile phase with gradient elution. The selected reaction monitoring transitions of   m / z 753 → m / z 330 and m / z 827 → m / z 330 were applied for ICG and IR-820 (the internal standard, IS), respectively. The method was selective and linear over a concentration range of 50-1,500 ng/ml. The method was validated for sensitivity, accuracy, precision, extraction recovery, matrix effect, and stability in liver tissue homogenates. ICG extraction recoveries ranged between 85 and 108%. The intra- and inter-day precisions were less than 6.28%. The method was applied to a bio-distribution study to compare the amount of ICG levels from mice treated with HFn-ICG and free ICG. The analyses of the homogenate samples from the two types of treatment showed that the concentration levels of ICG is approximately six-fold higher than those of free ICG (1,411 ± 7.62 ng/ml vs. 235 ± 26.0 ng/ml) at 2 h post injection.

Biomarkers of Low-Level Environmental Exposure to Benzene and Oxidative DNA Damage in Primary School Children in Sardinia, Italy.

BACKGROUND: The main anthropic sources of exposure to airborne benzene include vehicular traffic, cigarette smoke, and industrial emissions. METHODS: To detect early genotoxic effects of environmental exposure to benzene, we monitored environmental, personal, and indoor airborne benzene in children living in an urban area and an area near a petrochemical plant. We also used urinary benzene and S-phenylmercapturic acid (S-PMA) as biomarkers of benzene exposure and urinary 8-hydroxydeoxyguanosine (8-OHdG) as a biomarker of early genotoxic effects. RESULTS: Although always below the European Union limit of 5 µg/m3, airborne benzene levels were more elevated in the indoor, outdoor, and personal samples from the industrial surroundings compared to the urban area (p = 0.026, p = 0.005, and p = 0.001, respectively). Children living in the surroundings of the petrochemical plant had urinary benzene values significantly higher than those from the urban area in both the morning and evening samples (p = 0.01 and p = 0.02, respectively). Results of multiple regression modelling showed that age was a significant predictor of 8-OHdG excretion, independent of the sampling hour. Moreover, at the low exposure level experienced by the children participating in this study, neither personal or indoor airborne benzene level, nor personal monitoring data, affected 8-OHdG excretion. CONCLUSIONS: Our results suggest the importance of biological monitoring of low-level environmental exposure and its relation to risk of genotoxic effects among children.