Mast Cells and Arachidonic Acid Cascade in Inflammation

Prostaglandin D2 PGD2 is a major cyclooxygenase metabolite of arachidonic acid produced by mast cells and it is released following allergen challenge in diseases, such as allergic diseases. PGD2 may act as a neuromodulator and as an allergic and inflammatory mediator. In allergic diseases, activated mast cell synthesizes prostaglandin D2 (first cyclo-oxygenate mediator) which has bronchoconstrictive and vasodilating effects and attracts several leukocytes. It has been found that activated mast cells, challenged with physiological and non- physiological secretagogues, release elevated histamine and tryptase and chymase, leukotrienes B4, C4 and D4, 5-hydroxyeicosatetraenoic acid, PGD2, Platelet Activating Factor (PAF), heparin, and high-molecular-weight neutrophil chemotactic factor and cytokines/chemokines. PGD2 exerts its biological activity through the DP and CRTH2 receptors and their cDNA cloning which were characterized 15 years ago. In this report, we revisited the biological effects of arachidonic acid compounds released by activated mast cells in allergic and inflammatory states.

Blood pressure changes and polycyclic aromatic hydrocarbons in outdoor workers

OBJECTIVES

Everyday outdoor workers are exposed to chemicals including the polycyclic aromatic hydrocarbons (PAHs). The aim of the study is to evaluate the relationship between hydroxypyrene and blood pressure in outdoor workers.

MATERIALS AND METHODS

374 subjects of both sexes entered the study. We evaluated the assay of urinary hydroxypyrene (1-HOP); their blood pressure (BP) was measured in upright position and in the supine position and the correlation between the levels of 1-HOP and BP was assessed using Pearson test and linear multiple regression.

RESULTS

The results obtained show that in the total sample the levels of urinary 1-OHP are negatively associated with systolic and diastolic BP in supine position and in upright position. The significance is maintained despite the stratification of the sample according to age; in non-smokers we found a negative relationship between 1-OHP and differential blood pressure, both systolic and diastolic.

CONCLUSIONS

The results of the study suggest that occupational exposure to PAHs may be able to significantly influence the blood pressure probably acting on the autonomic nervous system.

Immunotoxicity and Sensitizing Capacity of Metal Compounds Depend on Speciation

Immunotoxicity of metal compounds is an issue of great importance due to the recent industrial application of metals with unknown toxicity on the immune system and the discovery of metal intermediary compounds not sufficiently studied yet. In this report we show results of our study on the immunotoxicity of the following metals: the Platinum group elements (Platinum, Palladium, Rhodium), Titanium and Arsenic. We applied functional and non functional assays and investigated both innate and adaptive immune systems, in particular, cell proliferation, cytokine production by PBMCs and O−2 production by neutrophils. We obtained the following results: only some Ti compounds (Titanocene, Ti ascorbate and Ti oxalate) show immunotoxicity. Trivalent As compounds (Sodium arsenite and tetraphenyl arsonium chloride) are more immunotoxic than the other investigated As compounds. Genotoxicity of Pt group compounds is in the following order: Pt < Rh < Pd. Immunotoxicity of Pt group compounds is in the following order: Pd < Pt < Rh. Lymphocytes and macrophages show a different reaction of neutrophils to metal toxicity. We can conclude that these studies show that metal immunotoxicity depends on speciation. In general speciation provides additional and often essential information in evaluating metal toxicity. However, there are many difficulties in applying speciation in investigating toxico-kinetic aspects to many metals, mainly due to the lack of information about the existence and significance of species and to the lack of analytical methods for measuring species in biological samples.

Clastogenic but Not Apoptotic Effects on Human Artery Endothelial Cells by Concentrations of Inorganic Lead Inhibiting Their Nitric Oxide Production

Human coronary artery endothelial cells (HCAEC 5156) were cultured as monolayers and exposed to concentrations of lead (as acetate, Pb) in the culture medium similar or lower than those commonly found in the blood of human beings occupationally or environmentally exposed to this element. Only at the concentration of 200 ng/mL, Pb reduced growth rate of HCAEC 5156 cells starting from the 3rd day and up to the 5th day of incubation. On the other hand, Pb (0.2, 2 and 200 ng/mL) increased concentration-dependently micronuclei formation in binucleated HCAEC5156 cells, as it was shown by the cytokinesis-blocked micronucleus assay (CBMN assay) carried out after 48 hours of exposure to the metal. However, Pb was unable, at all the above concentrations, to induce apoptosis in HCAEC 5156 cells following a 48 hour-exposure, as shown by an electrophoretic apoptotic DNA fragmentation test. Moreover, Pb (2 and 200 ng/mL) reduced significantly the concentration of nitric oxide (NO, determined analytically as L-citrulline) in both culture medium and cytosol of HCAEC 5156 cells following a 7 day-exposure to the element. Results were discussed also in relation to evidences of other studies reporting genotoxic and/or apoptotic effects of Pb on various cell types at very elevated dosages or concentrations. The observed clastogenic effects of Pb were explained through a series of mechanisms involving interactions between oxygen reactive species and NO and/or reduced NO synthesis in the endothelium, thus leading to a depressed NO bioavailability. This research first shows that Pb is provided with clastogenic but not apoptotic effects on cultured human endothelial cells. It was emphasized that such effects are induced by Pb concentrations similar to those commonly found in blood and tissues of laboratory animals showing Pb induced cardiovascular and/or neuropsychological alterations.

Neurobehavioral Functions, Serum Prolactin and Plasma Renin Activity of Manganese-Exposed Workers

Objective of this study was to assess effects of manganese (Mn) exposure on 56 workers employed in a Mn welding workshop of a machine building factory in Taiyuan (Shanxi Province, P.R. China) for a mean period of 16.1 years. The mean air Mn level in the workshop was 138.4 μg/m3. Neurobehavioral Core Test Battery (NCTB), including the Profile of Mood States (POMS), was performed. Blood pressure (BP) increase following immediate stand-up (BP-IS), serum prolactin (PRL) and plasma renin activity (PRA) in supine position were also determined. Most of the NCTB scores of the Mn-exposed workers were lower than those of the controls, while the POMS scores were higher, indicating a Mn-induced impairment of neurophysiological functions and a deflection of mood towards negative emotion states. PRL values of the Mn-exposed workers were higher than those of the controls. BP-IS of Mn-exposed workers was significantly lower than that of the controls. PRA of the same workers was augmented more than 200 %. In the Mn-exposed workers, the higher PRL values are possibly due to a reduced inhibitory effect on pituitary lactotrope cells by the tubero-infundibular dopamine system; the decreased BP-IS was referred to imbalance between the sympathetic and parasympathetic activities, whereas the higher basal PRA was thought to depend on neuroendocrine changes (including increased central sympathetic tone) and/or on a direct effect of Mn on renal juxta-glomerular cells. On the whole, this study demonstrates that occupational Mn exposure is responsible for neurobehavioral changes coexisting with alterations of neuroendocrine and humoral systems.

“In Vitro” Comparative Immune Effects of Different Titanium Compounds

Exposure to Ti compounds is today an occupational and environmental health hazard. Object of this study was to determine “in vitro” effects of different Ti salts on cultured human peripheral blood mononuclear cells (PBMC) proliferation and cytokine release. 10−4 and 10−7 M Ti compounds did not modify spontaneous PBMC proliferation. Ti dioxide (a biocompatible material and sunscreen component) did not exert effects on phytoemagglutinin (PHA) stimulated PBMC proliferation and on PHA stimulated IFN-γ and TNF-α release from PBMC. On the other hand, 10−4 M Ti oxalate (with wide industrial applications) and Ti ascorbate (used mainly in agriculture) inhibited about 70 % the PHA stimulated PBMC proliferation; both these Ti compounds at 10−4 and 10−7 M concentrations significantly inhibited TNF-α release, while only Ti oxalate inhibited that of IFN-γ. Titanocene (used in chemotherapy) did not exert effects on PBMC proliferation but markedly inhibited IFN-γ and TNF-α release. On the whole, this study demonstrates that Ti dioxide is not immunotoxic; Ti oxalate shows marked immunotoxicity; titanocene exerts selective toxicity on cytokine release but not on PBMC proliferation, while Ti ascorbate affects TNF-α release from PBMC but not IFN-γ release. In conclusion, these data show that immunotoxicity of Ti depends on speciation.

Job strain in different types of employment affects the immune response

The immune system, in cooperation with neuroendocrine functions, defends from cancer and infections mainly by the activity of blood natural killer (NK) cells. Blood NK activity may be influenced by the type of employment since work is the central part of life; moreover, job stress is a situation affecting both neuroendocrine and immune systems. This study examines anxiety (by STAI 1 and 2), job strain (by the Karasek's JCQ) and blood NK activity (by an in vitro radio-isotopic method) of 134 male workers. These men, over 38 years old with stable employment, were working in factories, in construction yards, in offices, as hospital attendants or as self-employed craftsmen. Workers in factories and in construction yards, with high job strain, showed lower NK activity, while office employees, with low job demand, and craftsmen with low anxiety and elevated decision latitude, showed higher NK activity; the level of NK activity of the hospital attendants was between the other groups. In conclusion, this study confirms that the type of employment, related to job stress, affects blood NK activity. Moreover, blood NK activity may be used in the bio-monitoring of workers at high risk.

[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.

Immunotoxicity of nanoparticles

The interaction between NPs and immune system has been demonstrated, however, the data available are limited. Among all traits, i.s. hydrophilicity, lipophilicity, catalytic activity, composition, electronic structure, capacity to bind or coat surface species and solubility, the dimension, and consequently the surface area, seems to be the main factor that contribute to the interactions of NPs with biological tissues and immune system in particular. Certain NPs accumulate to regional lymph nodes, where they can be taken up and processed by dendritic cells, interact with self-proteins and, hence, modify their antigenicity and elicit altered immune responses and even autoimmunity. Other NPs may induce allergic sensitization, i.e. allergic contact dermatitis to Pd. In vitro studies demonstrated that NPs can modulate cytokine production toward Th1 (Pl, Pd, Ni, Co) or Th2 (Ti, mw and sw Carbon) production patterns. Some NPs have been linked to allergic sensitization, however, It is unlikely that NPs can act as a hapten inducing a specific IgE production, likely they can act as adjuvant and induce a specific pattern of cytokines, antibody and cells that favor allergic sensitization to environmental allergens. Furthermore, NPs demonstrated pro-inflammatory effects in the lung in experimental animal with increased expression on IL-1beta, MIP-1alpha, MCP-1, MIP-2, keratinocyte chemoattractant, TARC, GM-CSF, MIP-1alpha and activation of the stress-activated MAPKs p38 and JNKs. All considered, the available data suggest that through the elicitation of an oxidative stress mechanism, engineered NPs may contribute to pro-inflammatory disease processes in the lung, particularly allergy.

Work stress and innate immune response

Several reports highlight the relationship between blood NK cytotoxic activity and life style. Easy life style, including physical activity, healthy dietary habits as well as good mental health are characterized by an efficient immune response. Life style is related to the type of occupational activity since work has a central part in life either as source of income or contributing to represent the social identity. Not only occupational stress, but also job loss or insecurity are thus considered serious stressful situations, inducing emotional disorders which may affect both neuroendocrine and immune systems; reduced reactivity to mitogens and/or decreased blood NK cytotoxic activity was reported in unemployed workers or in those with a high perception of job insecurity and/or job stress. Although genetic factors have a key role in the pathogenesis of autoimmune disorders, occupational stress (as in night shifts) was reported associated to an increased incidence of autoimmune disorders. Monitoring blood NK response may thus be included in the health programs as an indirect index of stressful job and/or poor lifestyle.

[The development of organizational comfort: organizational training as strategic instrument for changing]

The organizational comfort has been defined as the relationship between people and work environment. The supervisor's functions imply organizing and relation competences, listening and observation, communication and negotiation. Unfortunately, the reality is quite different: there are often situations of communication disorder between the supervisor and the worker, where the first, unaware of his role and responsibility, doesn't understand the worker's needs, doesn't communicate rightly the risk, doesn't develop any emphatic attitude and organize work without thinking to individual inclinations and limitations. The worker perceives this situation as increasing sensation of tiredness and working stress. The workers, often involved in this organization, have to ask overtime medical examinations to obtain some limitations. Observing this big increase of limitations in some firms with working people relatively young, we have decided to elaborate an experimental project involving both the occupational doctor and the psychologist. We analyzed the relations between the supervisor and the worker, with the aim to increase organizational comfort, through the diffusion of anonymous questionnaires or training courses about behaviour analyses and communication strategies, verifying any possible modifications of the organization after our intervention.

[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.

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.

[Comparison of the training schemes of the specialization schools of the public health area: a rational basis for a proposal of a core curriculum for the university training programme contained in article 38 of Legislative Decree (D.Lgs) 81/2008]

A document by the B. Ramazzini College of University Teachers of Occupational Medicine of the Italian Society of Occupational Health and Industrial Hygiene (S.I.M.L.I.I). The aim of this document was to compare the professional competence, training profile and core curricula of the three main specialization courses in the Public Health postgraduate medical area, i.e., Occupational Medicine, Hygiene and Preventive Medicine, and Forensic Medicine, such as contained in the Ministerial Decree (D.M) of 1 August 2005. We set out to identify, using clear and objective criteria, the knowledge and skills that specialists in Hygiene or Forensic Medicine must develop, in accordance with Art. 38 of the new Italian law on safety ahd health at work (D.Lgs 81/2008), in order to be authorized to perform occupational health activities as "Competent Physicians" (CP). The comparison revealed significant differences in structure and content among the three courses. In particular, compared to the course in Occupational Medicine, the courses in Hygiene and in Forensic Medicine both lack clinical training, including diagnostic and therapeutic skills, risk-oriented occupational health activities, biological monitoring, assessment of individual susceptibility, and clinical or instrumental procedures to prevent and detect occupational diseases. Furthermore, the specialization course in Hygiene lacks any training regarding the criteria and methods for assessing the individual worker's fitness for work, while the course in Forensic Medicine lacks any training in occupational risk assessment and management. From this comparison, a list was derived of the education and training debits that specialists in Hygiene or Forensic Medicine should cover (credits) in order to be authorized to perform CP activities as indicated by the new law. A core curriculum is proposed here, based on the corresponding credits, for use as a reference.

Impact of IL-32 on Histamine Release by Human Derived Umbilical Cord Blood Mast Cells

IL-32 is onae of the last important cytokines discovered, produced mainly by T cells, natural killer cells, and epithelial cells. Probably many other different cells are a source of IL-32, which has been found to be a powerful pro-inflammatory mediator. Here we studied the effect of IL-32 on histamine release by human-derived cord-blood mast cells. In these studies we found that IL-32 significantly stimulates the release of histamine only at high concentrations (100 ng/ml) while at 10 or 50 ng/ml it had no effect. These results were found for the first time and demonstrate that IL-32 may play an important role in allergic and inflammatory diseases.

Stimulation of CCL2 (MCP-1) and CCL2 mRNA by substance P in LAD2 human mast cells

Chemokines are cytokines with chemotactic properties on inflammatory cells and other cell types. Chemokine (C-C motif) ligand 2 (CCL2), which is also called monocyte chemotactic protein 1 (MCP-1), is a potent chemotactic molecule that attracts lymphocytes, monocytes, mast cells, and memory T cells, but not neutrophils. CCL2/MCP-1 represents a link between the activation of monocytes, lymphocytes, basophils, mast cells, and eosinophils in inflammatory disorders, such as the late-phase allergic reaction. This C-C chemokine also plays a role in regulating Th-cell cytokine production and leukocyte trafficking. Laboratory of allergic diseases (LAD) cells is the first reported human mast cell line that closely resembles a primary culture of CD34+-derived human mast cells. These cells were cultured in vitro and treated with different concentrations of substance P (SP) for the production of CCL2/MCP-1. We used calcium ionophore as a positive control for stimulating transcription and translation of CCL2/MCP-1. The stimulation of SP on CCL2/MCP-1 was statistically significant (P < 0.05) compared with the control (untreated cells). In this study, we determined the expression and secretion of CCL2/MCP-1 from SP-activated LAD2 human mast cells in vitro. The levels of CCL2/MCP-1 from SP-activated LAD2 human mast cells were higher at 10 microM and at 18 h incubation compared with controls. This effect was also revealed on CCL2/MCP-1 messenger RNA (mRNA) expression, as determined by reverse transcriptase polymerase chain reaction (RT-PCR) analysis. Our data suggest that SP is an important neurotransmitter that can stimulate the chemokine CCL2, which plays a fundamental role in inflammation by recruiting inflammatory cells to specific cites.

[Effects of occupational stress and job insecurity on the immune response]

The immune system responds to environmental signals. High blood NK activity characterizes individuals with a good life style and mental health condition or those exerting physical activity. Mental instability, depression and a poor life style exert opposite effects. A poor work environment with low social support or repetitive and shift work, as well as unemployment, are shown to affect the immune response, inducing autoimmune disorders or reducing NK cell activity. We studied anxiety, job strain and insecurity and the NK cell activity of 118 men and 68 women working in a university. A group of older male employees with high job strain and anxiety showed lower NK cell activity. Young male employees with temporary jobs showed reduced NK cell activity, while male doctors in training in Dental School underwent increased job strain, but anxiety, job insecurity and immune response were within a normal range. Analysis of all the data of the men showed that anxiety and job insecurity (more than occupational stress) reduce NK cell activity, thus affecting the health status. On the other hand, the results of this study on women may not exclude that nurses working in hospital in a stressful work environment may show reduced immune response.

Autism and immunity: revisited study

Autism spectrum disorder is of interest neurochemically because it represents a relatively homogeneous disorder with regard to disease development, abnormal cognitive development and intellectual development disturbance. A consistent finding in autistic children is a high number of mast cells and a high level of serotonin which is also found at elevated concentrations in the urine of autistic patients. In addition, a dysfunction of clinical conditions, such as gastrointestinal and immunological symptoms, is frequently noted in autistic children, however, IgE does not appear to be prevalent in these children but probably an increase of cytokines/chemokines produced by mast cells at an early age may play an important role. Therefore an immune hypothesis, involving also autoimmunity, is one possible pathogenetic mechanism in autism. In conclusion, mast cell activation could contribute to immune and neuroinflammatory abnormalities that are evident in patients with autism spectrum disorders.

Chlamydia pneumoniae and atherosclerosis: the role of mast cells

Chlamydia pneumoniae (C. pneumoniae), a respiratory pathogen, has been implicated in the pathogenesis of atherosclerosis, an inflammatory progressive disease, characterized by the formation of atherosclerotic plaques. Among several types of inflammatory cells involved in the atherogenesis process, recently particular attention has been directed toward the mast cells. Experimental studies have provided several mechanisms by which C. pneumoniae and mast cells could play a role in all stages of atherosclerosis, from initial inflammatory lesions to plaque rupture. C. pneumoniae, as well as mast cells, may actively participate both through the production of cytokines and matrix-degrading metalloproteinases and by provoking apoptosis of atheroma-associated vascular cells, key events in plaque rupture. This mini-review provides a brief overview on adventitial inflammatory effects of C. pneumoniae and mast cells and their potential role in plaque instability. In addition, in this paper we review the role of mast cells in innate immunity.

Occupational stress, job insecurity and perception of the health status in Italian teachers with stable or temporary employment

The object of this study is to analyse job stress and insecurity and the perception of symptoms (health status) of 374 teachers (30 women and 74 men) with stable or temporary employment in schools in Pescara, a town in Central Italy. Job strain and job insecurity were analysed by an Italian version of the Karasek?s questionnaire, the perception of the health status by a 12 item test, and state and trait anxiety by STAI I and STAI II. There were no significant differences depending on the type of school. The young women with temporary contracts showed only higher levels of job insecurity than the women with stable employment, while those over 50 years old also showed more elevated values of job strain. Men with temporary contracts showed higher levels of both job insecurity and state and trait anxiety. The following highly significant correlations were observed: a) in women, job strain and perception of symptoms vs STAI I and STAI II (p<0.001); b) in men, job strain, job insecurity and perception of symptoms vs STAI II; job strain vs perception of symptoms as well as a negative correlation of decision latitude vs job insecurity, STAI I and STAI II (p<0.01). These results highlight differences in the perception of job insecurity between men and women. In particular, the decision latitude (skill decision + decision authority) plays an important role in men; temporary employment is mainly related to anxiety in men, while anxiety enhances the perception of poor health status mainly in women.

Is necroptosis a death pathway in aluminum-induced neuroblastoma cell demise?

Besides being an aggravating factor secondary to major physiological alterations in degenerative diseases, aluminum has also been considered as a risk factor in the etiology. Although many in vivo and in vitro data are in favor of apoptosis and necrosis being involved in Al induced neurodegenerative processes, there is considerable evidence that very complex events may contribute to neural cell death. Necroptosis, a novel cell death pathway, was recently reported to contribute to ischemia brain injury. It is different from, but associated with, apoptosis and necrosis, the two common major pathways of cell demise. In the present study, SH-SY5Y cells were put under stress by Al, a potential degenerative cell death inducer. Nec-1, a specific inhibitor, was used to identify necroptosis. The characteristics observed in Nec-1 and Al treated SH-SY5Y cells showed that necrotic morphological changes were reduced, and a sharp decrease of necrotic rate was detected. Besides, there were Al-induced mitochondria membrane potential decreasing, reactive oxygen species remaining, and autophagosomes declining. The mechanism of Nec-1s effect on cell death may be related to caspases pathways. To our best knowledge, this is the pioneer report on necroptosis in mixed human neural cell death pathways, which might offer a novel therapeutic target for neurodegenerative diseases, and an extended window for neuroprotection.

The latest interleukin: IL-33 the novel IL-1-family member is a potent mast cell activator

IL-33, a member of IL-1 family, induces the differentiation of T-cells (depending on the phosphorylation of MAPKs and NF-kB) and is involved in T-cell mediated immune responses. IL-33 is also involved in the production of IL-5, IL-4 and IL-13 and several chemokines. In this editorial we show the importance of IL-33 in allergic diseases and its role as an inflammatory cytokine. In addition, the induction of certain chemokines by IL-33 may candidate this new cytokine as a mediator in inflammatory and autoimmune diseases and may prove to be a therapeutic target for the prevention of these diseases.

Neuropeptide substance P induces mRNA expression and secretion of CXCL8 chemokine, and HDC in human umbilical cord blood mast cells

PURPOSE

Mast cells play an important role in innate and acquired immunity and are thought to be the cellular origin of most proteases and cytokines. Substance P (SP) and its receptor, NK-1R, play critical roles in immune regulation in human and animal models of inflammation.

METHODS

We used mature human cord blood mast cells (HCBMC) differentiated from cord blood CD34+ precursor activated with SP in culture.

RESULTS

Our data indicate that Substance P strongly activates mature HCBMC in releasing CXCL8 expression and secretion (

CONTROL

1.200 +/- 1.0; SP: 4.10 +/- 0.90; P < 0.01). Moreover, in a RT-PCR, HCBMC expressed CXCL8 mRNA after Substance P activation. Since calcium ionophore A23187 is a pharmacological activator that raises cytosolic free calcium ion concentraion and stimulates mast cells in the production and secretion of proinflammatory compounds, it was used as positive control. In addition, we found that HCBMCs generate the transcription of histidine decarboxylase (HDC), the enzyme responsible for the generation of histamine from histidine, after SP treatment. Since CXCL8 is a member of the CXC chemokine subfamily with potent chemotactic activity and is a primary inflammatory cytokine we conclude that our results, obtained from HCBMC cultures, a good and valid model in vitro, support the concept that the neurogenic system modulates inflammatory events by Substance P-mediated HCBMC chemokine CXCL8 release.

CONCLUSION

The expression, synthesis and release of CXCL8 suggest an increase of inflammatory process in vivo mediated by the recruitment and infiltration of inflammatory cells in inflamed tissues.

Blood natural killer activity is reduced in men with occupational stress and job insecurity working in a university

PURPOSE

To examine the immune response to job strain and insecurity of 88 men working in a university, divided according to age and type of employment.

METHODS

Anxiety, job strain, job insecurity and subjective symptoms were measured by questionnaires. Blood NK cytotoxic activity was determined by an in vitro method and lymphocyte subpopulations by flow-cytometry analysis.

RESULTS

Employees (over 40 years old) in a library showed higher values of job strain, anxiety and subjective symptoms and lower blood NK activity than the controls. The young employees with temporary employment showed high job insecurity and reduced blood NK activity, while the young sanitary staff with temporary position showed normal immune response. NK cytotoxic activity of the recruited men was negatively correlated with anxiety, work load and job insecurity.

CONCLUSIONS

Not only anxiety and depression but also high levels of job strain and/or insecurity may affect the health status by reducing blood NK activity.

How Do Rat Cortical Cells Cultured with Aluminum Die: Necrosis or Apoptosis?

Aluminum (Al) exposure has been implicated as the cause of neural cells loss in several neurodegenerative diseases. Therefore, defining the mechanism of neural cell death in Al toxicity and degenerative diseases might lead to the development of therapeutic agents which promote neural cell survival. Furthermore, knowledge of cell death pathways might facilitate the discovery of treatments for neurodegeneration. However, the death mode of neural cells triggered by Al has not been firmly established. The present study focuses on understanding the pathway of cells death in cultured cortical cells treated with Al. Primary neurons cultured alone, astrocytes cultured alone, and neuron/astrocyte co-cultures obtained from newborn rats were incubated with Al at the concentrations of 0, 0.5,1.0, or 2.0 mM for 72 h. Morphological changes were observed with an inverted phase microscope, a fluorescent microscope, and an electron microscope. Simultaneously, the rate of apoptosis was quantified with flow cytometry. Morphological characteristics of apoptosis such as cell shrinkage, aggregation and fragmentation of chromatin, membrane buds, and formation of membrane-bound apoptotic bodies were observed in Al-treated neurons, while none of these characteristics were found in Al-treated astrocytes. Quantitative results of apoptotic rates detected with flow cytometry indicated a typical apoptosis progression in neurons at various dosages. A concentration-dependent relationship between Al concentration and apoptotic rates confirmed that apoptosis is the prominent cause of cell death in primary cultured neurons, even at a concentration lower than 2 mM. Both necrosis and apoptosis are evident in neuron/astrocyte co-cultures, but the intensity of apoptosis is much less compared with that of neurons, suggesting that astrocytes may be especially important for neuronal survival in the presence of Al.

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.

[Occupational stress and job insecurity in men working in a university]

77 men working in a university were investigated. Trait and state anxiety were determined by STAI I and STAI II; job strain (job demand/decision latitude), social support and job insecurity were analysed by a 46 item Karasek's questionnaire and subjective symptoms by a 12 item test. The employees of a library (mean age 49 years), in contact with students, showed significantly higher values of job strain, STAI I, STAI II and subjective symptoms than a control group of employees with similar age. Young employees and sanitary staff with temporary employment showed higher level of job insecurity than control subjects with stable position. Blood cytotoxic activity (reported in another study) was significantly lower in the old employees with job strain or in the young employees with job insecurity (but not in the sanitary staff) than in the controls; this demonstrates that not only occupational stress but also job insecurity may play an important role in affecting the health status.

[Prevention of low back pain diseases in a center for the disabled]

Our unit of occupational medicine has been asked to solve the problem of an incrising percentage of workers affected by low-back pain in a clinic for patients with handicaps. The consequence of this affections caused frequently absences at work. We organized a course for training about correct methods for moving patient not self-sufficient. The 84 workers, all female (aged 30-45), had to sign on a card all the problems they found at work and their possible solutions according to them. Then we put the cards in a box and we red each one, signing on a blackboard the problems, using a red pen and the solutions proposed, in blue. Bed organization, turnation of patient, and the difficulties in the use of lifter were the principal problems, solved trought the training course made. Then we obtained a reduction in absence at work for low-back pain of about 40% after six months since the beginning of a course of posture exercises made in the same clinic one day a week after work.

[Risk perception in a group of dentists from Abruzzo]

Dentist's office represents an area with high infectious risk both for workers and patients. With our study we tried to analyse the relationship between dentists and prevention. We studied 104 dentists who had to answer to a questionnaire composed by 25 questions on topics such as job management, risk perception, measures adopted for prevention and knowledge about normatives regarding safety at work. From the answers we can conclude that dentists know the risk present in their work and use correctly the individual preventive dispositives; make blood control to test hepatitis markers, in particular HCV. But only 68% made HBV vaccination. Many dentists,even if they know the way of transmission of HIV, avoid to cure positive patient.

[Anxiety, job stress and job insecurity among teachers with indefinite or definite time contract]

Object of this study was the occupational stress of 336 teachers (276 women and 60 men) with stable or temporary employment in schools of Pescara, town of Central Italy. The levels of anxiety were determined by STAI and STAI II, those of job strain", "job insecurity" and social support by the Karasek's questionnaire, and the perception of subjective symptoms by a 12 item test. There were no significant differences depending on the type of school. The women with temporary contract showed higher levels of "job insecurity", while the men with temporary job showed also higher values of STAI I and STAI II. The scores of anxiety of the women were positively correlated with "job strain", "job insecurity" and perception of subjective symptoms and negatively with social support, while the only correlations of STAI I and STAI II of men showing statistical significance of men was that with "job insecurity. Job strain was negatively correlated with the perception of symptoms both in women and men. These results evidence differences in the occupational stress of men and women; in particular, job insecurity may enhance anxiety in men.

Quality in emergency departments: a study on 3,285,440 admissions

INTRODUCTION

A multi-centre study has been conducted, during 2005, by means of a questionnaire posted on the Italian Society of Emergency Medicine (SIMEU) web page. Our intention was to carry out an organisational and functional analysis of Italian Emergency Departments (ED) in order to pick out some macro-indicators of the activities performed. Participation was good, in that 69 ED (3,285,440 admissions to emergency services) responded to the questionnaire.

METHODS

The study was based on 18 questions: 3 regarding the personnel of the ED, 2 regarding organisational and functional aspects, 5 on the activity of the ED, 7 on triage and 1 on the assessment of the quality perceived by the users of the ED.

RESULTS AND CONCLUSION

The replies revealed that 91.30% of the ED were equipped with data-processing software, which, in 96.83% of cases, tracked the entire itinerary of the patient. About 48,000 patients/year used the ED: 76.72% were discharged and 18.31% were hospitalised. Observation Units were active in 81.16% of the ED examined. Triage programmes were in place in 92.75% of ED: in 75.81% of these, triage was performed throughout the entire itinerary of the patient; in 16.13% it was performed only symptom-based, and in 8.06% only on-call. Of the patients arriving at the ED, 24.19% were assigned a non-urgent triage code, 60.01% a urgent code, 14.30% a emergent code and 1.49% a life-threatening code. Waiting times were: 52.39 min for non-urgent patients, 40.26 min for urgent, 12.08 for emergent, and 1.19 for life-threatening patients.

Occupational asthma due to low molecular weight agents

Occupational asthma is defined as variable airflow obstruction and airways hyperresponsiveness caused by exposure to agents present in the workplace. Low molecular weight agents such as isocyanates, aldehydes, anhydrides, colophony, dyes, persulphate, amines, acrylates and metals are steadily increasing as causative agents of occupational asthma. Isocyanates, aldehydes and anhydrides my cause sensitisation through an IgE mediated response in some workers. These agents act as haptens which combine with a carrier protein to form a complete antigen. Assays for the detection of specific IgE are standardized for very few agents and have a good specificity, but poor sensitivity. The diagnosis of occupational asthma relies not only on a suggestive hystory showing that asthma is caused or exacerbated specifically by work exposure, but in most cases needs to be confirmed by objective means. Combined monitoring of lung function parameters, such as peak expiratory flow rate at the work site and non specific bronchial hyperresponsiveness during and away from exposure, is necessary. The "gold standard" for confirming a diagnosis in an individual worker still remains the specific bronchoprovocation test, which has now reached a high degree of sensitivity, specificity and reproducibility for agents such a s isocyanates. In occupation asthma due to low molecular weight agents there are no individual risk factors which could predict the susceptibility to develop the disease. The primary prevention is based on appropriate interventions tn the workplace. The strict medical surveillance of workers may allow the early diagnosis and removal from further exposure in order to prevent morbidity and disability.

Follow up study on the immune response to low frequency electromagnetic fields in men and women working in a museum

Seven women and eight men, exposed to low frequency (50 Hz) electromagnetic fields (EMFs) in a museum for 20 hours a week, were investigated in the years 1999 and 2005. During the first study, the mean EMF exposure in the working place was 1.7 microT and 1.1 microT, respectively. In the first investigation, the EMF-exposed men showed reduced blood NK lymphocytes in relation to controls, while EMF-exposed women presented reduced PHA-stimulated IFN-gamma release from peripheral blood mononuclear cells (PBMC). In the year 2005, blood cytotoxic activity, state and trait anxiety (STAI I and II, respectively) and occupational stress were also investigated. The scores of STAI I and II of the control women were slightly higher than those of the control men. EMF-exposed men showed higher occupational stress but normal immune parameters. EMF-exposed women showed, in relation to controls, lower PHA-stimulated IFN-gamma release from PBMC and reduced blood cytotoxic activity/CD45+-CD16+-56+ NK lymphocytes (but not per ml of blood). One of the women exposed to EMF, who worked a night shift, showed marked lymphopenia with very low NK lymphocytes and reduced IFN-gamma release; these immune parameters returned to normal following a change of work site. This study suggests that low frequency EMFs affect the immune functions of women more than those of men. Moreover, the determination of immune parameters seems to be a useful marker of the health effects of exposure to EMFs.

Effect of occupational stress and anxiety on natural killer lymphocyte activity of men and women employed in a university

The aim of this study is the immune response of the staff of a university and a museum (referent group). 46 women and 40 men with similar mean age (44 years) were investigated. The first group of women (A) worked in libraries, B in offices in contact with students, C as secretaries and D in a museum. One group of men (E) was composed of employees of the university, one worked in a library temporarily located underground (F) and the last group (G) in a museum. STAI I and II (state and trait anxiety, respectively), and occupational stress were measured by questionnaires. Blood samples were collected for determining NK cytotoxic activity vs human erythroleukaemia cells and the lymphocyte subsets CD45+, CD45+-CD3+, CD45+-CD3+-CD4+, CD45+-CD3+-CD8+, CD45+-CD3-CD8+, CD3+-CD16+-56+ and CD3+-CD19+. Group B showed significantly higher score of occupational stress and STAI I (but not of STAI II) than the other groups of women. Group F of men showed higher levels of occupational stress and both STAI I and II than groups E and G. Group B of women and F of men also showed significantly lower values of blood cytotoxic activity. The scores of STAI I and II were negatively correlated with the cytotoxic activity expressed per ml of blood and/or total lymphocytes. and/or NK CD45+-CD16+-CD56+ cells. In conclusion, this study shows that occupational stress may increase anxiety which is negatively correlated with blood cytotoxic activity. This is a useful tool for determining the health effects of stress.

The immune response of women with prolonged exposure to electromagnetic fields produced by radiotelevision broadcasting stations

Twelve women, five of them housewives, exposed in their residences to electromagnetic fields (EMFs)emitted by radio-television broadcasting stations for a mean period of 13 years, were investigated. The EMFs in the balconies of the homes were (mean + S.D.) 4.3 + 1.4 V/m in the year 2000 and 3.7 + 1.3 V/m in 2005, while the exposure in the nearby area was <2.0 V/m. The EMF exposed women showed in 2000 reduced blood NK lymphocytes as well as PHA stimulated PBMC proliferation and IL-2 and IFN-gamma release. In the year 2005, the EMF exposed women and 48 control women with similar ages(mean 43 years), smoking habits, atopy and social level were investigated. State (temporary) and trait(tendency of the personality) anxiety were determined by STAI I and II, respectively. Blood cytotoxic activity and lymphocyte subsets were also determined. The ratio STAI I/STAI II of the EMF exposed group was lower than that of the control group. The blood cytotoxic activity of the exposed women was lower (p<0.01), percent of B CD45+-CD19+ lymphocytes higher and percent of CD45+-CD3+-CD8+ cells lower (p<0.05). Moreover, cytotoxic activity/CD45+-CD16+-56+ NK lymphocytes of the controls was negatively correlated with STAI I and STAI II (p<0.001). In conclusion, this study demonstrates reduced blood cytotoxic activity and increased trait anxiety in relation to state anxiety in EMF exposed women. An effect of EMFs on immune functions, in part mediated by nervous mechanisms, may be hypothesized. However, the influence of lifestyle may not be excluded.

The effects of sub-acute exposure to palladium on cytokines in male Wistar rats

Palladium (Pd) and its compounds can cause sensitization, asthma and skin disorders. Sensitization to Pd is increasing in the European general population. In this study, Wistar rats were exposed for two weeks to 0, 1, 10,100 and 250 ng ml-1 of Pd as potassium hexachloro-palladate in drinking water. At the end of exposure, possible changes in two type-1 cytokines (IL-2, INF-gamma) and one type-2 cytokine (IL-4) in the serum were measured. Our findings suggest that, after a sub-acute exposure, a moderate level of Pd causes a strong Th2 response. This also occurs at higher concentrations. Although no effect on Th1 cells is observed up to a concentration of 250 ng/ml, a significant increase in IL-2 production is reported thereafter. These results therefore suggest that in sub-acute exposure, Pd exerts a significant immuno-modulating effect, altering the Th1/Th2 cytokine balance, even at low exposure doses. Our preliminary results indicate the need to carry out further studies to observe the effect of different types of Pd compounds and to measure other types of cytokines both in the animal model used in our study and in other models.

Shift work and autoimmune thyroid disorders

Stress induces autoimmune disorders by affecting the immune response modulation. Recent studies have shown that shift work stress may enhance the onset of the autoimmune Graves hyperthyroidism. On the other hand, the possible association between occupational stress and autoimmune hypothyroidism has not yet been investigated. In order to detect the possible association between shift work and subclinical autoimmune hypothyroidism we investigated the prevalence of isolated anti-peroxidase thyroid (TPO) autoantibodies in 220 shift workers and in 422 day-time workers. Subclinical autoimmune hypothyroidism was diagnosed by the concomitant presence of high anti-TPO values and TSH levels higher than 2.51 mU/l. Anti TPO antibodies were measured by chemiluminescent technology (Advia Centaur) (a value above 60 IU/l was considered altered). Subclinical autoimmune hypothyroidism was diagnosed in 7.7 percent shift workers and in 3.8 percent day-time workers with a statistically significant difference: Odds Ratio (OR) 2.12, 95 percent Confidence Interval (CI) 1.05 to 4.29; p=0.03. The difference persisted after multivariate analysis taking into account age, sex, smoking habits, alcohol intake, familial history of autoimmune thyroid disease and exposure to radiation as possible confounders: OR. 2.24, 95 percent CI.1.01 to 4.94, p 0.05. Altered anti- TPO autoantibodies were found in 13.6 percent shift workers and in 8.6 percent day-time workers OR. 1.64, 95 percent CI.1.03 to 2.74, p=0.05. The significant difference was still detectable after multivariate analysis: OR. 1.95, 95 percent CI. 1.09 to 3.48, p=0.02. Our data show a significant association between shift work and autoimmune hypothyroidism. This finding may have implications in the health surveillance programs.

Cobalt nano-particles modulate cytokine in vitro release by human mononuclear cells mimicking autoimmune disease

The use of particles from micro to nanoscale provides benefits to diverse scientific fields, but because a large percentage of their atoms lie on the surface, nanomaterials could be highly reactive and pose potential risks to humans. Due to their wide range of application, Cobalt nano-particles are of great interest both in industry and in life-science. To date, there are few studies on Co nano-particle toxicology. In this respect, this study aims at evaluating in vitro the potential interference of Co nano-particles on the production of several cytokines (IL-2, IL-4, IL-6, IL-10, IFNgamma and TNFalpha) by PBMCs, comparing their effects to those of Co micro-particles and Co solution (CoCl2). Cells were cultured in Opticell flasks with escalating concentrations (10-5, 10-6 and 10-7 M), of Co nano and micro-particles and CoCl2 or without metal. Cytokines were quantified in the supernatants using a human Th1/Th2 cytokine cytometric bead array. Co micro-particles showed a greater inhibitory effect compared to other Co forms. Its inhibitory activity was detected at all concentrations and towards all cytokines, whereas Co solutions selectively inhibited IL-2, IL-10 and TNF-alpha at maximal concentration. Co nano-particles induced an increase of TNF-alpha and IFN-gamma release and an inhibition of IL-10 and IL-2: a cytokine pattern similar to that detected in the experimental and clinical autoimmunity. On the basis of the obtained data, immune endpoints should be sought in the next series of studies both in vitro and in vivo in subjects exposed to cobalt nano-particles.

[Predisposition and evaluation of sanitary procedures in occupational medicine]

"Sanitary procedures" are used to perform preventive and periodic clinical examinations of workers. Their main purpose is to evaluate health status and function of target organs. Periodic medical procedures are used to evaluate the possible onset of precocious and reversible modifications of the health status induced by exposure to specific risk factors during working activities. Moreover, they must be considered an essential step of a correct management of the quality.