Optimization of a fast and sensitive method based on matrix solid-phase dispersion-LC-ms/ms for simultaneous determination of phthalates and bisphenols in mussel samples

Bisphenols and phthalates are wide classes of endocrine disrupting chemicals (EDCs) extensively used as additives in plastic products. In this study, a fast and reliable analytical method based on matrix solid-phase dispersion (MSPD) coupled with LC-MS/MS was developed and optimized for simultaneous determination of 8 bisphenols and 7 phthalates in raw mussel extract. The LC-MS/MS method was tested for linearity (R2), inter- and intra-day repeatability, limit of detection and quantification, both for matrix-free and matrix-matched solutions. The MSPD method was optimized in terms of ratio between sample and sorbent, and the type and quantity of the eluents in order to maximize the recoveries and to minimize matrix effects. The obtained recoveries (values between 75% and 113%), limits of detection (values between 0.048 and 0.36 µg kg-1), limits of quantification (values between 0.16 and 1.28 µg kg-1), repeatability (RSD% between 1.30% and 8.41%) and linearity (R2 > 0.998) were satisfactory and suitable for the determination of target micropollutants in food samples. In addition, the low solvent consumption and fast execution make this method ideal for routinely determinations of bisphenols and phthalates in mussels.

Human semen quality and environmental and occupational exposure to pollutants: A systematic review

Background

The aim of the present systematic review was to evaluate the correlation between the exposure to environmental and/or occupational pollutants and possible alteration of semen quality, focalizing the attention on the studies performed using a biomonitoring approach.

Methods

The review was conducted from inception to May 11 2023, according to the PRISMA Statement 2020 and using the following databases: Scopus, Pubmed and Web of Science. The protocol was registered on PROSPERO (CRD42023405607). Studies were considered eligible if they reported data about the association between exposure to environmental pollutants and alteration of semen quality using human biomonitoring. The quality assessment was carried out by the use of the Newcastle-Ottawa Quality Assessment Scale.

Results

In total, 21 articles were included, conducted in several countries. The main matrices used for biomonitoring were urine and blood and the most sought-after contaminants were bisphenols, phthalates, pesticides, polychlorinated biphenyls, polycyclic aromatic hydrocarbons, heavy metals and other inorganic trace elements. The results of the studies demonstrated a significant positive correlation between the increase of the pollutants' levels in the biological matrices examined and some alterations of the semen quality indicators, such as a decrease in motility, concentration and morphology of the spermatozoa.

Conclusions

Male fertility can be negatively affected by the exposure to environmental and/or occupational pollutants. Human biomonitoring programs may be considered a useful tool for specific surveillance programs devoted to early highlight subjects who are more exposed to environmental pollutants in order to reduce risk exposure.

Natural Mineral Water and Diuresis: A Systematic Review

The present systematic review is aimed at evaluating the diuretic effects determined according to the natural mineral water consumption on healthy individuals. This systematic review has been performed following the guidelines of the PRISMA (preferred reporting items for systematic reviews and meta-analyses) Statement, investigating PubMed, Scopus, Web of Science and Cochrane Library from inception to November 2022. Studies performed both on animals and on humans were considered. After screening, a total of 12 studies have been identified. Of these, 11 studies were performed in Italy and 1 in Bulgaria. The time range of publication is very wide, ranging from 1962 to 2019 for human studies and from 1967 to 2001 for animal studies. All the included studies found an increase in diuresis determined according to the consumption of natural mineral water, in some cases after just one administration of the tested water. However, the quality of the studies is not so high, especially for the research conducted many years ago. Thus, it would be desirable to carry out new clinical studies using more appropriate methodological approaches and more refined methods of statistical data processing.

Impact of Air Pollution on the Composition and Diversity of Human Gut Microbiota in General and Vulnerable Populations: A Systematic Review

Recently, growing attention has focused on the impact of air pollution on gut microbiota as a possible mechanism by which air pollutant exposure increased the risk for chronic diseases, as evidenced by in vivo studies demonstrating important exposure-induced alterations in the diversity and relative abundance of gut bacterial taxa. This systematic review provides updated state-of-art findings of studies examining the impact of air pollution on the human gut microbiota. Databases PubMed, Scopus, and Web of Science were searched with the following strategy: "air poll*" AND "gut micro*" OR "intestinal micro*"; moreover, a total of 10 studies were included. Overall, there is the evidence that short-term and long-term exposure to air pollutants have the potential to alter the composition and diversity of gut microbiota; some studies also correlated air pollution exposure to adverse health effects (impaired fasting glucose, adverse pregnancy outcomes, and asthma attacks) via alterations in the composition and/or function of the gut microbiota. However, the evidence on this topic is still scarce, and large cohort studies are needed globally.

Determination of Carbonyl Compounds in Different Work Environments: Comparison between LC-UV/DAD and LC-MS/MS Detection Methods

There were two analytical methods for the determination of 12 carbonyl compounds (CCs) by using liquid chromatography (LC) coupled with mass spectrometry (MS/MS) and diode array detector (UV/DAD) that were developed and applied to 52 samples that were collected in 10 workplaces. Linearity (0.996 < R² < 0.999), intra-day repeatability (0.7 < RSD% < 10), and inter-day repeatability (5 < RSD% < 16) were acceptable for both techniques, but the highest sensibility of the MS/MS method allowed us to correctly quantify 98% of the samples (versus 32% by UV/DAD). The comparison of the concentrations that were obtained by quantifying the same sample with both techniques showed good agreement for acetaldehyde and formaldehyde (0.1 < % deviation < 30) but much higher for the less abundant congeners. In real samples, formaldehyde was the most abundant congener (concentrations between 2.7 and 77 µg m^-3), followed by acetaldehyde (concentrations between 1.5 and 79 µg m^-3) and butyraldehyde (concentrations between 0.4 and 13 µg m^-3). In all the beauty salon samples, instead, the most abundant congener was acetaldehyde (concentrations between 19 and 79 µg m^-3), probably associated with the use of beauty products. Principal components analysis (PCA) confirms the ubiquitous character of formaldehyde and highlights the influence of minority CCs on different workplaces.

P202 PRETREATMENT WITH ANTAGONISTS OF P2Y12 PLATELETS RECEPTORS IN ST–ELEVATION MYOCARDIAL INFARCTION: CLINICAL AND ANGIOGRAPHIC OUTCOMES

Background

The use of antagonists of P2Y12 platelets receptors as antiplatelets drugs is a cornerstone in the treatment of ACS. Many efforts are made to understand the right timing of beginning this therapy with the purpose to reduce intra– and periprocedural complications (stent thrombosis, no reflow phenomenon). The rationale behind “pretreatment” (administration of antagonists of P2Y2 platelet receptor before the coronarography) is valuable but the evidences are lacking, also in the setting of ACS–STEMI.

Method and Objectives

We conduct an observational, monocentric (Ospedale dell’Angelo – Venezia Mestre), retrospective study including patients with STEMI (1st January 2016 – 9th august 2018). We compared two strategies of administration of clopidogrel, ticagrelor and prasugrel (pretreatment vs no pretreatment). Primary endpoints were bleeding BARC 3–5, acute or subacute stent thrombosis and TIMI flow grade &gt; 0 in the culprit coronary. Secondary endpoints were cardiovascular and no cardiovascular in–hospital mortality and in–hospital neurological complications.

Results

We studied 501 patients (199 in the group pretreated and 302 in the group no pretreated). The median time from first medical contact to PCI was 70,5 minutes in the pretreated group and 60 minutes in the no pretreated group (p = 0.022). No significant differences between the two groups were observed in terms of acute or subacute stent thrombosis (OR 3.72 [0.82–14.20], p = 0.09) e TIMI flow grade &gt; 0 in the culprit coronary (OR 1.11 [0.77–1.58], p = 0.58). In the multivariate analysis we observed that bleeding BARC 3–5 significantly were increased in the pretreated group (adjusted OR 2.78 [1.13–6.83, p = 0.025). In the subgroup analysis, the pretreated subjects with age &gt; 75 were at augmented risk of bleeding BARC 3–5.

Conclusions

Pretreatment in the setting of ACS–STEMI is not associated with benefits in terms of acute or subacute stent thrombosis and perfusion of culprit coronary but may cause clinically relevant bleedings, in particular in the elderly (age &gt; 75).

P2 IMPACT OF CATHETER ABLATION ON ARRHYTHMIC STORM: A SINGLE–CENTER EXPERIENCE

Background

Arrhythmic storm (AS) is a medical emergency whom management is multidisciplinary and includes antiarrhythmic medications, sedation and mechanical circulatory support, as well as catheter ablation, a procedure that is gaining growing relevance in clinical practice, supported by guidelines.

Methods and Aims

It is a retrospective observational study of patients admitted to Cardiology Department of Ospedale dell’Angelo for AS from 2016 to 2021. The primary endpoint was the rate of arrhythmic recurrences and their clinical predictors; the secondary endpoint was a composite of all– cause death, LVAD or cardiac transplant. Successful CA was defined as no inducibility of any VT at the end of the procedure.

Result

We evaluated 74 patients. Catheter ablation (CA) was performed in 56 patients, while in the other 18 patients, the treatment of the arrhythmic emergency was limited to medical therapy. At a median follow–up of 10 months (range 4–36 months), the overall arrhythmic recurrence rate was 39.1% and AS recurrence occurred in 11% of patients; the incidence of the composite end–point of all–cause death, LVAD implant or cardiac transplant was 20.2%. B–blockers (85% vs 100%, p = 0.025) and successful CA (60% vs 88.6%, p = 0.021) were associated with less arrhythmic recurrences. At multivariate analysis, a successful CA was an independent predictor of arrhythmic recurrence free survival (HR 0.32, [0.11–0.94], p = 0.039), and of ICD shocks free survival (HR 0.087, [0.02–0.37], p = 0.001). ICD shocks at admission (8.06 ± 9.8 vs 3.18 ± 4.24, p = 0.005), NYHA class III–IV (46.6% vs 5%, p = 0.001), medical treatment (53.3% vs 83%, p = 0.031), ICD shocks during follow–up (53.3% vs 18,6%, p = 0.004) and AS recurrence (33.3% vs 10.1%, p = 0.039) were associated with an increased rate of the secondary endpoint.

Conclusions

In our real world experience of patients admitted for AS, CA was a predictor of arrhythmic recurrence free survival and may have a role in improving quality of life and prognosis by reducing ICD shocks. CA was an independent predictor of the reduced incidence of all–cause death, LVAD implant or cardiac transplant, although this finding might reflect a more severe cardiac disease of the medically treated patients than a real benefit of CA on mortality.

P146 A CASE OF TYROSINE–KINASE INHIBITOR INDUCED CARDIOTOXICITY

This case is about a 69 years–old woman with no prior cardiovascular disease and a history of rheumatoid arthritis;in 2017 underwent right nephrectomy for renal cancer. A few weeks before admission, due to evidence of secondary bone lesions at a follow–up CT–scan, a single dose of the tyrosine kinase inhibitor (TKI) Nivolumab was administered. On the same evening she suffered from a severe reacutization of arthritic symptoms, that led her Oncologist to suspend treatment with nivolumab, and oral corticosteroid therapy was initiated. The following weeks remained though characterized by intense persistent asthenia, severe arthralgias, profuse diarrhea and a syncopal episode; no chest pain was reported. Given the persistence of symptoms, she went to the Emergency Room. Initial work–up revealed a complete heart block, with a previously unknown right bundle branch block (see Figure 1). At blood tests there was a significant increase of troponin I to 7616 ng/L (Normal&lt;12ng/L), BNP 1113 pg/mL (NR &lt; 100 pg/mL), creatinine 2.34 mg/dL (NR 0.55–1.02mg/dL), CPK 1681 U/L (NR 10–145 U/L) and D–dimer 17780 mcg/L (NR &lt; 600). She was immediately transferred to our Cardiologic Intensive Care Unit, where an echocardiogram showed normally functioning ventricular chambers and no valvulopathies. Due to the ongoing acute kidney injury and the history of right nephrectomy, a coronary angiography was not immediately performed, considering the low probability of ACS (no typical symptoms, no regional wall motion abnormalities).Suspecting nivolumab–induced myocarditis, high–dose glucocorticoids were initiated. After a few days we observed persistence of bradycardia and complete AV block despite isoprenaline infusion, and due to signs of peripheral malperfusion (acute kidney injury, hypotension) a definitive leadless pace–maker Micra was implanted (this choice given the need of immunosuppressive therapy that could predispose her to device infections). After normalization of renal function, we performed a coronary angiography that showed normal coronary arteries. Despite the initial improvement of the clinical conditions, the patient suffered a fatal cardiac arrest due to electromechanical dissociation 3 weeks after admission. This case report is an important example showing the significant mortality of cardiotoxicity induced by tyrosine–kinase inhibitors, a side effect that every Cardiologist must be aware of in order to recognize it and immediately intervene with the appropriate therapy.

Exposure Profile to Traffic Related Pollution in Pediatric Age: A Biomonitoring Study

The aim of this study was to trace an exposure profile to traffic-derived pollution during pediatric age. For this purpose, two biomonitoring campaigns for the determination of urinary (u-) methyl tert-butyl ether (MTBE), ethyl tert-butyl ether (ETBE), tert-amyl methyl ether (TAME), and diisopropyl ether (DIPE) were carried out in two different periods of the year (summer 2017 and winter 2018), among a large sample of healthy children (n = 736; 5–11 years old) living in rural and urban areas in central Italy. The quantification of u-MTBE, u-ETBE, u-TAME, and u-DIPE was performed by HS-SPME-GC/MS technique and information on participants was collected by a questionnaire. u-DIPE concentrations resulted always under the LOQ. u-TAME mean levels were similar in both seasons (18.7 ng L⁻¹ in summer vs. 18.9 ng L⁻¹ in winter), while u-MTBE and u-ETBE levels were, respectively, 69.9 and 423.5 ng L⁻¹ (summer) and 53.3 and 66.2 ng L⁻¹ (winter). Main predictors of urinary excretion resulted the time spent in motor vehicles, being male and younger.

A survey on knowledge and awareness on the issue "microplastics": a pilot study on a sample of future public health professionals

BACKGROUND

Microplastics pollution represents a global public health concern. Since the greatest amount of microplastics are of anthropogenic origin, one of the most relevant strategies to reduce microplastics pollution is to raise awareness among the population and this is even more important for all those involved in public health prevention interventions. The aim of this study was to assess the level of knowledge and awareness on microplastics of a samples of future healthcare workers.

STUDY DESIGN

A cross-sectional study was performed on 151 university students in the field of Public Health, both pre- and post-graduate, attending the Sapienza University of Rome courses.

METHODS

A questionnaire consisting of three sections was administered to the participants. The first section assessed knowledge and awareness on microplastics, the second consisted of an informative brochure on microplastics, the third evaluated the awareness after reading the brochure, and interventions considered useful to manage microplastics pollution.

RESULTS

About 25% of participants had never heard of microplastics. The scores on knowledge about microplastics were low, and differences between the investigated courses were not statistically significant (p-Value=0.134). Internet was the main source of information on microplastics, while the scores describing concern about the investigated issue resulted always higher after reading the informative brochure respect to before reading.

CONCLUSIONS

The lack of knowledge about microplastics pollution highlights that future public health workers should be better informed and, therefore, able to transfer essential information to the population. Increasing general population's knowledge and awareness would increase risk perception and make all individuals more active actors for reducing microplastics pollution.

Occupational Exposure Assessment of Major and Trace Elements in Human Scalp Hair Among a Group of Eritrean Workers

The aim of the study was to evaluate occupational exposure to 40 elements among a group of Eritrean adults employed at the Medeber metal market by analysing human scalp hair samples and by investigating the role of some predictors (gender, age, and body mass index-BMI) on their levels. Scalp hair samples were collected from 60 subjects (32 subjects working at the Medeber metal market and 28 subjects not working at Medeber and not employed in other industrial or artisanal activities) and were analysed through inductively coupled plasma mass spectrometry to determine the contents of 40 major and trace elements. Information on participants was collected via questionnaire. Significant differences were found in the hair levels of certain elements between subjects working at the Medeber metal market and subjects not exposed. In particular, working at the Medeber metal market increased hair levels of Be, B, Cu, Zn, Mo, Cd, Sb, Tl, Pb, and Fe from 25 to 100%, while reduced Na, K, and Rb levels from 30 to 50%. With multivariate adjustment for age, gender, and BMI, the results confirm that working at Medeber significantly increased the hair levels of Cu, Zn, Sb, Pb, and Fe. This finding reveals the need for more accurate and routine biomonitoring surveys and the necessity of health promotion campaigns both for local decision-makers and workers to increase health promotion and safety in this workplace.

A Cross-Sectional Study on Benzene Exposure in Pediatric Age and Parental Smoking Habits at Home

After the introduction of the smoke-free legislation, household smoking has become the major source of environmental tobacco smoke (ETS) exposure for children. In our previous research, we found a strong association between urinary unmodified benzene (u-UB) levels and passive smoking exposure related to the home smoking policies (HSP). The aim of the study is to further investigate the impacts of several factors on ETS-exposure in childhood by using u-UB as tobacco-related carcinogen biomarker of exposure. Two cross-sectional studies were performed on the same target population of our previous research, in summer and winter season of the years 2017 and 2018, respectively. A questionnaire and a head space-solid phase micro-extraction/gas chromatography-mass spectrometry (HS-SPME/GC-MS) analytical method were used as investigative procedures. The improvement found in smoking habits, when compared to our previous surveys, reduced the levels of u-UB in children. However, significant differences related to the high number of smokers and smoked cigarettes, in total and at home, still persist. These differences are more relevant in the winter season. Finally, the only effective way for making homes completely smokefree is to develop public health policies for encouraging people to quit or drastically reduce smoking.

Multicentre evaluation of case volume in minimally invasive hepatectomy

Background

Surgical outcomes may be associated with hospital volume and the influence of volume on minimally invasive liver surgery (MILS) is not known.

Methods

Patients entered into the prospective registry of the Italian Group of MILS from 2014 to 2018 were considered. Only centres with an accrual period of at least 12 months and stable MILS activity during the enrolment period were included. Case volume was defined by the mean number of minimally invasive liver resections performed per month (MILS/month).

Results

A total of 2225 MILS operations were undertaken by 46 centres; nine centres performed more than two MILS/month (1376 patients) and 37 centres carried out two or fewer MILS/month (849 patients). The proportion of resections of anterolateral segments decreased with case volume, whereas that of major hepatectomies increased. Left lateral sectionectomies and resections of anterolateral segments had similar outcome in the two groups. Resections of posterosuperior segments and major hepatectomies had higher overall and severe morbidity rates in centres performing two or fewer MILS/month than in those undertaking a larger number (posterosuperior segments resections: overall morbidity 30·4 versus 18·7 per cent respectively, and severe morbidity 9·9 versus 4·0 per cent; left hepatectomy: 46 versus 22 per cent, and 19 versus 5 per cent; right hepatectomy: 42 versus 34 per cent, and 25 versus 15 per cent).

Conclusion

A volume–outcome association existed for minimally invasive hepatectomy. Complex and major resections may be best managed in high-volume centres.

Air quality assessment in different environmental scenarios by the determination of typical heavy metals and Persistent Organic Pollutants in native lichen Xanthoria parietina

The study was aimed to evaluate the ability of native lichen Xanthoria (X.) parietina to biomonitor and bioaccumulate some heavy metals (As, Cd, Co, Cr, Ni, Pb), PAHs, PCDDs, PCDFs, PCBs and PBDEs and to evaluate the use of the native X. parietina as a multi-tracer tool for scenarios characterized by different anthropogenic pressures. Samples of native X. parietina were collected in six different sites (two green, two residential and two industrial areas, respectively) and analyzed for the target compounds. The results show that X. parietina was a useful tool for the biomonitoring of air quality in the selected areas, and was able to bioaccumulate all the studied metals and POPs. In particular, the total concentrations dry weight (dw) ranged between 8.1 and 103.4 mg kg^-1 for metals, from 113 × 10³ to 183 × 10³ ng kg^-1 for PAHs, from 868 to 7685 ng kg^-1 for PCBs, from 14.3 to 113.8 ng kg^-1 for PCDDs/Fs (∑TEq = 0.9-7.1), and from 194 to 554 ng kg^-1 for PBDEs. Besides, in general, the levels of analytes recovered in the different samples of lichen show an increasing trend from green to industrial sites, especially for PCBs (mean values equal to 1218, 4253 and 7192 ng kg^-1 respectively for green, residential and industrial areas). The statistical approach, based on Pearson's correlation and principal component analysis tests, showed that one of the industrial sites was well-separated from the others, that resulted grouped due to some similarities.

Further Insights on Predictors of Environmental Tobacco Smoke Exposure during the Pediatric Age

Background: The smoking ban in public places has reduced Environmental Tobacco Smoke (ETS) exposure for non-smokers, but despite this, domestic environments still remain places at high risk of exposure, and, today, about 40% of children worldwide are exposed to ETS at home. The aims of the study are to investigate the contribution of several factors on ETS exposure among a group of Italian children and to evaluate the changes in smoking precautions adopted at home when the smoker is the mother, the father, or both parents, respectively. Methods: A cross-sectional study was performed on a sample of 519 Italian schoolchildren. Information was collected via a questionnaire. Results: 41.4% of the participants lived with at least one smoker. Almost half of the children exposed to ETS lived with one or more smokers who do not observe any home smoking ban. Lower maternal or paternal educational levels significantly increase the risk of ETS exposure at home and the "worst case" is represented by both parents who smoke. Conclusions: More effective preventive interventions are needed to protect children from ETS exposure. Some interventions should be specifically dedicated to smokers with a low educational level and to mothers that smoke.

Exposure to individual and multiple carcinogenic metals during paediatric age: an experience from an Italian urban scenario

BACKGROUND

Exposure to single and multiple carcinogenic metals and/or semimetals represents a major environmental risk factor for public health. In particular, children are more susceptible to environmental pollutants than adults, but specific studies are still limited. The aims of the present study were: 1) to trace the exposure and co-exposure profiles to eight known or suspected carcinogenic metals and semimetals (As, Be, Cd, Co, Cr, Ni, Pb, and Sb); and: 2) to evaluate the influence of some possible interfering/confounding factors on the exposure to these elements during childhood.

STUDY DESIGN

Cross-sectional study.

METHODS

We recruited 159 healthy Italian children attending a primary school of the urban area of Rome, Italy. Selected metals were determined by inductively coupled plasma mass spectrometry on urinary samples collected at the end of a "typical" day (one sample for each child), while information about possible confounding/interfering factors were collected via questionnaires.

RESULTS

The great part of the studied children resulted co-exposed to the monitored metals: 83.2%, 69.2%, 51.0% and 29.3% of the participants were concurrently exposed to at least two, three, four and five trace elements, respectively. Gender was the only one among the investigated variable that significantly influenced the co-exposure, with females resulting at lower risk (OR = 0.392; 95 IC = 0.156 - 0.989; p < 0.047).

CONCLUSIONS

Given the importance of protecting child's health and the risks related to the exposure to carcinogenic metals, especially when they occur simultaneously, other researches in this field are strongly recommended.

Seven-day Storage of Single Donor Platelets in Polyolefin Bags: Clinical, Biochemical, Morphological and Microbiological Evaluation

We compared the in vitro and in vivo function of fresh and stored platelet concentrates (PCs) collected by an automated continuous-flow blood cell separator (CS 3000 Fenwal) in a closed-system apheresis kit in order to evaluate the possibility of extending the storage time to seven days with the polyolefin container (PL-732). The initial 220 ml platelet volume (5.14 ± 1.23 x 1011) was divided into two parts. Half was transfused and the other half was stored for 7 days. All cultured units were negative for bacterial contamination. Mean counts for fresh and stored platelets were respectively 2.34 ± 0.59 and 2.17 ± 0.50 x 1011/100 ml of PCs (mean recovery 88.7 ± 11.9%). The pO2 levels were maintained during storage (179.9 ± 30.5 mmHg) but pCO2, pH, LDH, osmolality, glucose consumption, bicarbonates, ATP, and osmotic stress values changed significantly after 7 days storage. From a clinical point of view, in 14 patients receiving a total of 38 PC transfusions no statistically significant change in corrected post-transfusional levels was observed between fresh and stored PC. Biochemical and morphological data and clinical results suggest that PCs collected with CS-3000 blood cell separator in a closed system and stored for 7 days in polyolefin bags (PL-732) can be satisfactorily employed in clinical practice.

Cholestasis is the Main Determinant of Abnormal CA 19–9 Levels in Patients with Liver Cirrhosis

Background/Aims

Altered CA19–9 levels are commonly found in patients with liver cirrhosis though a clear explanation for this finding has not yet been given. The aim of this study was to investigate whether CA19–9 levels might be related to alterations in biochemical parameters and/or to functional impairment in cirrhotic patients with and without hepatocellular carcinoma. Methods: We studied 126 patients with liver cirrhosis, 60 of whom also had hepatocellular carcinoma. CA19–9 values were related to clinical, biochemical and functional parameters. In half of the patients CA19–9 levels were related to the monoethylglycinexylidide test, which is a dynamic liver function test.

Results

In more than half the cases CA19–9 values were above the upper limit. Liver function worsening as assessed by Child-Pugh's score and monoethylglycinexylidide test did not seem to influence the alteration of the marker. By contrast, in univariate analysis CA19–9 correlated with aminotransferases, γ-glutamyltransferase and alkaline phosphatase. Multivariate analysis showed that besides alkaline phosphatase also the presence of hepatocellular carcinoma might influence the alteration of CA19–9, although the marker was of no use for the diagnosis of liver cancer in patients with altered though not diagnostic α-fetoprotein levels.

Conclusions

In our study we confirmed the correlation of CA19–9 levels with cholestasis and cytolysis parameters. Moreover, we found no association between CA19–9 levels and impaired liver function as assessed by means of the Child-Pugh's score and the monoethylglycinexylidide test, which is cholestasis-independent and explores liver metabolic and clearance activities. The cholestatic picture that characterizes liver cirrhosis might enhance the expression and passage of the marker from the bile to the blood. The addition of CA19–9 assessment is not useful for the diagnosis of hepatocellular carcinoma in patients with non-diagnostic levels of α-fetoprotein. Caution should therefore be used when evaluating CA19–9 in cirrhotic patients with cholestasis, since false positive results may occur.

Assessing indoor air quality of school environments: transplanted lichen Pseudovernia furfuracea as a new tool for biomonitoring and bioaccumulation

The aim of this research is to evaluate the ability of transplanted lichen Pseudovernia (P). furfuracea to biomonitor and bioaccumulate in urban indoor environments. The elements As, Cd, Cr, Cu, Hg, Ni and Pb and 12 selected polycyclic aromatic hydrocarbons (PAHs) were used to assess P. furfuracea as a biomonitoring tool for the indoor air quality of school environments. To achieve this purpose, lichen samples were exposed for 2 months in the outdoor and indoor environments of five school settings located in urban and rural areas. The results demonstrated that transplanted lichen P. furfuracea is a suitable biomonitoring tool for metals and PAHs in indoor settings and can discriminate between different levels of air pollution related to urbanisation and indoor conditions, such as those characterised by school environments. A transplanted lichen biomonitoring strategy is cost-effective, "green", educational for attending children and less "invasive" than traditional air sampling methods. The feasibility of indoor monitoring by P. furfuracea is a relevant finding and could be a key tool to improve air quality monitoring programmes in school scenarios and thus focus on health prevention interventions for children, who are one of the most susceptible groups in the population.

Protein Kinase Cζ Regulation of Hypertrophic and Apoptotic Events Occurring during Rat Neonatal Heart Development and Growth

The development and growth of the rat heart implies hyperplasia, which stops at birth, and hypertrophy, allowing cardiac mass to grow in response to programmed genetic events along with to haemodynamic overload. Moreover, hypertrophy is accomplished to apoptosis which controls the final number of myocardial cells, deletes vestigial structures, and takes part in remodelling the organ. Since at the basis of all these processes, which lead to the complete development of the heart, the activation of specific signalling pathways underlies, attention has been addressed to the role played in vivo by Protein Kinase Cζ (PKCζ) in regulating NF-kB signalling system and “intrinsic” mitochondrial apoptotic route at days 1, 4, 10 and 22 of rat life. In fact, a role has been assigned to PKCζ in indirectly phosphorylating IKBα, which peaks between 10 and 22 days, through a IKK determining, in turn, NF-kB activation, concomitantly to cytochrome c/Apaf 1 co-localization in the cytoplasm and caspase-9/caspase-3 activation, which leads to the occurrence of apoptosis. Thus a key role for PKCζ in regulating the hypertrophic and apoptotic events leading to establishment of complete function in rat neonatal heart is here suggested.

Sensitive multiresidue method by HS-SPME/GC-MS for 10 volatile organic compounds in urine matrix: a new tool for biomonitoring studies on children

A HS-SPME method coupled with GC-MS analysis has been developed for simultaneously measuring the concentration of 10 volatile organic compounds (VOCs) (benzene, toluene, ethylbenzene, o-, m-, and p-xylene, methyl tert-butyl ether, ethyl tert-butyl ether, 2-methyl-2-butyl methyl ether, and diisopropyl ether) in urine matrix as a biomonitoring tool for populations at low levels of exposure to such VOCs. These compounds, potentially toxic for human health, are common contaminants of both outdoor and indoor air, as they are released by autovehicular traffic; some of them are also present in environmental tobacco smoke (ETS). Thus, the exposure to these pollutants cannot be neglected and should be assessed. The low limits of detection and quantification (LODs and LOQs <6.5 and 7.5 ng L(-1), respectively) and the high reproducibility (CVs <4 %) make the developed method suited for biomonitoring populations exposed at low levels such as children. Further, the method is cost-effective and low in time-consumption; therefore, it is useful for investigating large populations. It has been applied to children exposed to traffic pollution and/or ETS; the relevant results are reported, and the relevant implications are discussed.

Probabilistic Inference in Credal Networks: New Complexity Results

Credal networks are graph-based statistical models whose parameters take values in a set, instead of being sharply specified as in traditional statistical models (e.g., Bayesian networks). The computational complexity of inferences on such models depends on the irrelevance/independence concept adopted. In this paper, we study inferential complexity under the concepts of epistemic irrelevance and strong independence. We show that inferences under strong independence are NP-hard even in trees with binary variables except for a single ternary one. We prove that under epistemic irrelevance the polynomial-time complexity of inferences in credal trees is not likely to extend to more general models (e.g., singly connected topologies). These results clearly distinguish networks that admit efficient inferences and those where inferences are most likely hard, and settle several open questions regarding their computational complexity. We show that these results remain valid even if we disallow the use of zero probabilities. We also show that the computation of bounds on the probability of the future state in a hidden Markov model is the same whether we assume epistemic irrelevance or strong independence, and we prove a similar result for inference in naive Bayes structures. These inferential equivalences are important for practitioners, as hidden Markov models and naive Bayes structures are used in real applications of imprecise probability.

The oxidation of aminoethylcysteine ketimine dimer by oxygen reactive species

The prominent spontaneous reaction of aminoethylcysteine ketimine in the neutral pH range is the concentration-dependent dimerization (Hermann, 1961). The carboxylated dimer first produced loses the free carboxyl yielding the more stable decarboxylated dimer (named simply the dimer in this note). In the search for a possible biochemical activity of this uncommon tricyclic compound we have assayed whether it could interact with oxygen reactive species (H2O2, O2 (-),(•)OH) thus exhibiting a scavenging effect of possible biomedical interest. The dimer interacts with H2O2 producing compounds detectable by chromatographic procedures. The presence of Fe(2+) stimulates the oxidative reaction by yielding the hydroxyl radical (the Fenton reaction). Using the system xanthine oxidase-xanthine as superoxide producer, the dimer oxidation by O2 (-) has also been documented. Among the oxidation products the presence of taurine and cysteic acid has been established. Identification of remaining oxidation products and investigation of the possible function of the dimer as a biological scavenger of oxygen reactive species are now oncoming.

[Innovation in the ergonomic procedures for evaluating risk in building activities of the Abruzzo region (Italy)]

After the earthquake of L'Aquila, INAIL further stimulated the local Universities to train specialists in the prevention of occupational risks on construction sites. Since 2005 the University of Chieti-Pescara evaluated occupational stress (through the Karasek's JCQ) as well as perception of occupational risk of the building workers. Moreover, procedures (including planning) in the field of building technology were analyzed. The perception of job strain of the workers in building activities were high because of elevated job demand and low decision latitude. The risk perception was higher regarding dangers producing immediate injury. There was no direct relationship between considering the job dangerous and having attended training courses, while the relationship between risk perception and past injury events was marked. At present, we are also evaluating, by instrumental methods, the biomechanical overload of workers, due to the main repetitive and forceful manual activities.

Perception of occupational risk by rural workers in an area of central Italy

The aim of this study is to analyze the subjective perception of risks for rural workers in Abruzzo, an area of central Italy. A group of 273 workers were asked to fill in a questionnaire which included, apart from general information, questions relative to six different types of risks normally found in the field of agriculture. The types of risks considered were: falling from a height, manually moving loads, overturning/accident whilst driving an agricultural tractor, noise and vibration, use of pesticides, the risk of being cut/injured. The workers were requested to assess, on a scale of 1 to 3, both the probability of an accident taking place and the consequent damage which could result from each of the risks considered. The assessment of the risks provided by the workers was related to the objective assessment of the risks carried out by the study group, also on the basis of objective data provided by INAIL (Italian insurance company) indexes, to highlight the eventual under/over estimations of risk. Furthermore, the possible correlation was evaluated between having received specific training regarding work safety and the workers perception of the risk. The results showed that approximately 11 percent of the workers do not consider their job as being dangerous; the risk perceived by the workers is higher for accidents that cause an immediate injury compared to those which cause professional illnesses, except the risk deriving from noise/vibrations. A direct correlation was found between the job as being dangerous and having attended courses on accident prevention.

p53 and telomerase control rat myocardial tissue response to hypoxia and ageing

Cellular senescence implies loss of proliferative and tissue regenerative capability. Also hypoxia, producing Reactive Oxygen Species (ROS), can damage cellular components through the oxidation of DNA, proteins and lipids, thus influencing the shortening of telomeres.

Since ribonucleoprotein Telomerase (TERT), catalyzing the replication of the ends of eukaryotic chromosomes, promotes cardiac muscle cell proliferation, hypertrophy and survival, here we investigated its role in the events regulating apoptosis occurrence and life span in hearts deriving from young and old rats exposed to hypoxia.

TUNEL (terminal-deoxinucleotidyl -transferase- mediated dUTP nick end-labeling) analysis reveals an increased apoptotic cell number in both samples after hypoxia exposure, mainly in the young with respect to the old. TERT expression lowers either in the hypoxic young, either in the old in both experimental conditions, with respect to the normoxic young. These events are paralleled by p53 and HIF-1 α expression dramatic increase and by p53/ HIF-1 α co-immunoprecipitation in the hypoxic young, evidencing the young subject as the most stressed by such challenge. These effects could be explained by induction of damage to genomic DNA by ROS that accelerates cell senescence through p53 activation. Moreover, by preventing TERT enzyme down-regulation, cell cycle exit and apoptosis occurrence could be delayed and new possibilities for intervention against cell ageing and hypoxia could be opened.

Patient-reported outcomes and gut dysmotility in functional gastrointestinal disorders

BACKGROUND

Unlike chronic idiopathic intestinal pseudo-obstruction (CIIP), severe digestive syndromes that are not characterized by episodes resembling mechanical obstruction remain poorly characterized. The present study compared clinical features, small bowel motility, and quality of life (QoL) in patients with CIIP or severe functional gastrointestinal disorders (SFGID), compared to irritable bowel syndrome (IBS).

METHODS

We enrolled 215 consecutive patients: 70 CIIP, 110 malnourished SFGID [body mass index (BMI) 17.8±1.8kg m(-2) ] and 35 non-malnourished SFGID (BMI 22.8±3.6kgm(-2) ).

KEY RESULTS

Abnormal motor patterns that fulfilled diagnostic criteria for small bowel dysmotility were virtually absent in IBS patients, but were recorded in69 CIIP patients (98.6%), 82 malnourished SFGID patients (74.5%;), and 23 SFGID patients without malnutrition (65.7%) (P<0.0001). CIIP patients presented more frequently abnormal activity fronts, lack of response to feeding, and hypomotility than malnourished and non-malnourished SFGID patients (61.4%vs 42.7% and 31.4%, P<0.05 only vs non-malnourished SFGID; 8.6%vs 0.9% and 2.9%; 21.4%vs 0.9% and 0%, P<0.05). Quality of life mean scores were all significantly lower in CIIP patients and malnourished SFGID patients than in IBS. Bodily pain, general health, and vitality scores were lower in CIIP also compared to non-malnourished SFGID.

CONCLUSIONS & INFERENCES

Chronic idiopathic intestinal pseudo-obstruction and SFGIDs are frequently associated with small bowel dysmotility and marked derangements of QoL which are significantly more severe than in IBS and result particularly in being severe in patients with recurrent sub occlusive episodes or inability to maintain a normal body weight.

Patient-reported outcomes and gut dysmotility in functional gastrointestinal disorders

BACKGROUND

Unlike chronic idiopathic intestinal pseudo-obstruction (CIIP), severe digestive syndromes that are not characterized by episodes resembling mechanical obstruction remain poorly characterized. The present study compared clinical features, small bowel motility, and quality of life (QoL) in patients with CIIP or severe functional gastrointestinal disorders (SFGID), compared to irritable bowel syndrome (IBS).

METHODS

We enrolled 215 consecutive patients: 70 CIIP, 110 malnourished SFGID [body mass index (BMI) 17.8±1.8kg m(-2) ] and 35 non-malnourished SFGID (BMI 22.8±3.6kgm(-2) ).

KEY RESULTS

Abnormal motor patterns that fulfilled diagnostic criteria for small bowel dysmotility were virtually absent in IBS patients, but were recorded in69 CIIP patients (98.6%), 82 malnourished SFGID patients (74.5%;), and 23 SFGID patients without malnutrition (65.7%) (P<0.0001). CIIP patients presented more frequently abnormal activity fronts, lack of response to feeding, and hypomotility than malnourished and non-malnourished SFGID patients (61.4%vs 42.7% and 31.4%, P<0.05 only vs non-malnourished SFGID; 8.6%vs 0.9% and 2.9%; 21.4%vs 0.9% and 0%, P<0.05). Quality of life mean scores were all significantly lower in CIIP patients and malnourished SFGID patients than in IBS. Bodily pain, general health, and vitality scores were lower in CIIP also compared to non-malnourished SFGID.

CONCLUSIONS & INFERENCES

Chronic idiopathic intestinal pseudo-obstruction and SFGIDs are frequently associated with small bowel dysmotility and marked derangements of QoL which are significantly more severe than in IBS and result particularly in being severe in patients with recurrent sub occlusive episodes or inability to maintain a normal body weight.

Effectiveness of FIr-B/FOx and liver metastasectomies in liver-only metastatic colorectal cancer (MCRC)

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Background: Effectiveness of liver metastasectomies was evaluated in liver-MCRC patients treated with FIr-B/FOx association in a previous phase II study (Bruera et al, submitted 2010).

Methods: Treatment schedule: 12h-timed-flat-infusion/5-Fluorouracil 900 mg/m2 days 1-2, 8-9, 15-16, 22-23; Irinotecan 160 mg/m2, Bevacizumab 5 mg/kg days 1, 15; Oxaliplatin 80 mg/m2 days 8, 22; every 4 weeks. Resection rate, activity, efficacy were analysed and compared in liver-only versus multiple metastatic sites and single versus multiple liver metastases.

Results: Liver-MCRC were 33: liver-only 22 patients (67%); multiple metastatic sites 11 patients (33%). Liver metastasectomies were performed in 13 patients (11 R0, 84.6%): 26% of 50 MCRC patients enrolled in the FIr-B/FOx phase II study; 39% of liver-MCRC patients; 54% of liver-only, 6 of 9 (67%) single and 6 of 13 (46%) multiple liver metastases; one liver and lung metastasectomy. Pathologic complete responses (CRs) were 2 (15%); downsizing with modification of surgical resectability, 9 patients (41%); conversion rate of unresectable liver metastases, 83%. Overall activity, including 3 clinical CR, in liver-only patients, 68%. ORR, PFS, OS, respectively: in liver-MCRC patients, 84%, 11 and 23 months; in liver-only metastases, 86%, 17 and 44 months; in liver metastasectomies, 100%, 21 months (PFS from liver surgery 10 months) and 47 months. Significantly increased efficacy: PFS and OS in liver-only versus multiple metastatic sites (p 0.006 and 0.011, respectively) and single versus multiple liver metastasis (p 0.026 and 0.022, respectively).

Conclusions: FIr-B/FOx chemotherapy increases resection rate of liver metastases, thus significantly improving efficacy of liver-only MCRC patients.

No significant financial relationships to disclose.

[In vitro study on the immune effects of the exposure to palladium nanoparticles]

Pd allergic contact dermatitis is increasing in the general population; aim of this preliminary study was to determine, in women with Pd sensitization, the cytokine release from PBMC exposed to Pd nanoparticles similar to those emitted from catalytic converters. PBMC of 8 non-atopic and of 5 Pd sensitized women were incubated with LPS stimulation in presence of Pd nanoparticles (5-10 nm) or potassium hexa-chloropalladate 10(-5) and 10(-6) M. This Pd salt inhibited IFN-gamma, TNF-alpha, IL-10 and IL-17 release from PBMC of non-atopic women, whereas Pd nanoparticles enhanced the release of IFN-gamma and inhibited that of TNF-alpha and IL-17. In the Pd-sensitized women, with high basal values of cytokine release, the 10(-5) M Pd salt (but not Pd nanoparticles) inhibited IL-10 and IL-17 release. In conclusion, Pd salt inhibits the cytokine release from PBMC, whereas Pd nanoparticles exert modulatory effects enhancing release of IFN-gamma which plays an important role in autoimmune diseases.

Natural history of intestinal failure induced by chronic idiopathic intestinal pseudo-obstruction

Chronic intestinal pseudo-obstruction is a severe, often unrecognized disease characterized by disabling and potentially life-threatening complications over time. The diagnosis is based on the evidence of typical clinical manifestations, radiological evidence of distended bowel loops with air-fluid levels, and the exclusion of any organic obstruction of the gut lumen. The radiological sign of intestinal occlusion allows the distinction from enteric dysmotility, which is characterized by better outcomes. Manometry can play a supportive role in defining the diagnosis, and differences in the manometric pattern of chronic intestinal pseudo-obstruction and enteric dysmotility have been shown. The disease is often unrecognized, and the diagnosis, therefore, delayed by several years. Thus, the majority of patients undergo useless and potentially dangerous surgeries. Long-term outcomes are generally poor despite surgical and medical therapies characterized by disabling and potentially life-threatening complications over time. A substantial percentage of patients requires parenteral nutrition. Failure of this nutritional support represents an indication for small bowel transplantation.

Correlation between BMI and PASI in patients affected by moderate to severe psoriasis undergoing biological therapy

Obesity is common in psoriatic patients, and it has been shown to be important for many aspects of the condition. In particular, low-calorie diets can improve the symptoms and response to treatment in pustular psoriasis. The present study investigates the influence of body-weight alteration on the disease's clinical manifestations in moderate to severe psoriasis patients treated with biological drugs. Finally, the influence of a caloric restriction was assessed. This observational transversal study enrolled 33 patients attending our Severe Psoriasis Outpatient Clinic, who were treated with biological drugs. Body Mass Index (BMI) was used as a diagnostic indicator of being overweight and of obesity. Waist circumference was also measured. Body weight and Psoriasis Area Severity Index (PASI) index were measured at follow-up visits at 4 and 8 months. Nonparametric test of Mann-Whitney was used to detect the differences between patient groups. Fisher's exact test was performed to evaluate the different results depending on the therapeutic changes of BMI. There was a strong prevalence of overweight-obese individuals in the group with a mean BMI of 30.59 +/- 6.94. Waist circumference was also above normal in the majority of the patients. Obese patients had a PASI index higher than the average of the whole group (25.03 +/- 12.43), with grade III obese patients having an average PASI of 44 +/- 3.37. At the first and second follow-ups, patients who put on weight did not achieve PASI 50; patients who had a stable weight presented variable response to treatment, while patients who decreased their weight achieved PASI 90 or PASI 75 even when not responding at the first. Further studies are needed to understand if the poor response observed in heavier patients is due to biological drugs pharmacokinetics or because therapy should be BMI based rather than administered in fixed doses, posing then an ethical consideration.

Safety in Construction Yards: Perception of Occupational Risk by Italian Building Workers

The purpose of this study is to analyse the perception of occupational risk by building workers in an area of Central Italy. Three hundred male building workers compiled questionnaires including 7 different types of dangers: falling from height, cuts and wounds to body and eyes, manual handling of loads, noise, vibrations and dust inhalation. The workers quantified, on a scale of one to five, the potential injury and frequency of occurrence of each risk, as well as providing information on the possibility of checking/avoiding the risk. Furthermore, attendance of the workers at previous specific courses on accident prevention and the effectiveness of these was evaluated. A possible correlation between the perception of job risk and having had previous injuries was also assessed. The results showed that about 35% of workers do not consider their job hazardous; moreover, the risk perception is higher regarding dangers producing immediate injury, as opposed to those producing occupational illnesses. Moreover, there is no direct relationship between considering the job dangerous for health and having attended training courses, while the relationship between risk perception and past injuries is more marked. In conclusion, accident prevention training is essential for building workers; however, it is even more important to improve the quality of workers' information in order to increase their awareness of danger.

Effects of palladium nanoparticles on the cytokine release from peripheral blood mononuclear cells of non-atopic women

The object of this study is to determine the cytokine release from PBMCs exposed to Pd model nanoparticles emitted from catalytic converters. PBMCs of 8 healthy non-atopic women were incubated in the presence of Pd nanoparticles (5-10 nm) or salt (potassium hexa-chloropalladate) 10-5 and 10-6 M. Release of cytokines in supernatant of PBMCs was then determined. In cultures without LPS, IL-10 and IL-17 release from PBMCs was inhibited by Pd salt, while Pd nanoparticles inhibited TNF-alpha and IL-17 release. In LPS-stimulated cultures, release of IFN-gamma, TNF-alpha, IL-10 and IL-17 was inhibited by Pd salt, whereas IFN-gamma release was enhanced and TNF-alpha and IL-17 release was inhibited by Pd nanoparticles. In conclusion, Pd salt inhibits cytokine release, whereas Pd nanoparticles exert modulatory effects enhancing the release of IFN-gamma, a Th1 cytokine typical of delayed allergic reactions. This result is interesting considering the increase of allergic contact dermatitis to Pd in people exposed to Pd nanoparticles in urban environments.

Protein kinase Calpha early activates splicing factor SC-35 during post-natal rat heart development

Rat myocardial fiber development and formation is a complex event which begins in the early stages of fetal life and continues until the end of the first month of life. In fact, a progressive morphological structure arrangement is observed until the 22nd day of life. These modifications are based on biochemical events which are switched on at plasma membrane level and then transduced into the nucleus. Since the presence of Protein Kinase C (PKC) inside the nucleus could allow the enzyme to phosphorylate also proteins located on chromatin, on nuclear matrix and speckles, in this study attention was paid to the role played by phospho-Protein Kinase C-alpha (p-PKCalpha) in regulating the activation of SC-35 splicing factor which leads to the occurrence of morphological modifications during post-natal rat heart development. Besides the parallel increase of the expression of both proteins up to 4/8 days of life, firstly p-PKCalpha and SC-35 co-localize at nuclear level at day 1 after birth, thus suggesting a main role of p-PKCalpha in modulating the early transcription of components related to post-natal rat heart development.

Combined effects of electromagnetic fields on immune and nervous responses

In technologically developed countries, there is concern about hazards from electromagnetic fields (EMFs). Several studies have reported that immune and neuroendocrine systems exert an integrated response to EMF exposure. The aim of this review is to summarize the results of studies on the effect of low and high frequency EMF on immune and neuroendocrine systems on which our research group has been working for several years.

[Technical survey of safety levels established in building sites in the Pescara area]

In 2006, in the context of the initiative aimed at "Promotion of safety and health of workers in construction yards", the Operative Unit of Occupational Health, University G. d'Annunzio, in collaboration with the Construction School of the Province of Pescara and INAIL, started a survey of construction yards around Pescara aimed at collecting data regarding respect of the specific law concerning construction yards and the risk perception of workers. The survey of 100 construction yards provided useful information towards a concise picture of safety levels obtained. In addition 300 interviews were carried out with workers to find out about their knowledge of accident prevention, how important they considered the use of personal protection devices, how often they used them, reasons for not using them, the devices most used,....and any injuries that occurred. The studied showed that, although the situation as improved compared to the past, further steps need to be taken.

[The perception of risk in construction workers]

Accidents in building sites led us to study risk perception in workers employed in this field. We disposed of 300 workers, aged 18-65, who had to answer to a questionnaries were signing among seven risks the more present in their activity, chosing among five levels. So for each risk the worker had to quantify parameters such as: danger, frequence of accidents, actitude to risk-control, training on risk. The risk of falling from high sites has been perceived as extremely dangerous but it is possible to control it. Less dangerous is eyes exposition to chemical agents or dust. Manual movementation of weight and lacerations would be the most frequent source of accidents. Moreover would be insufficient the capacity to control the rick related to Weight manual movementation and vibrations. Workers answered in questionnaries that risk training on vibration was not sufficient, on the contrary they knew the risk of falling from high site. So we conclude that to reduce accidents in building sites it is necessary make better training on field, modifying the individual behavior among workers.