Analytical characterization of movements of the spinal column and risk assessment due to repeated movements of the upper limbs of building painters.

Manual activities of construction workers may induce musculoskeletal disorders. This study on a group of painters aimed to analytically characterize movements of the spinal column by both lumbar motion monitor and television cameras and to determine, using the Occupational Repetitive Actions (OCRA) Index method, the risk exerted by repeated movements of the upper limbs. The main results are: painting with a roller generally exposes workers to a lesser risk for upper limbs than painting with a brush; a roller-stick fixed at the wrong length can lead to stretching of the back at lumbar and cervical levels; to remain within the range of 'acceptable risk' (OCRA Index evaluation), a worker should not paint a vertical wall for over 3 h if using a roller and 2.5 h if painting with a brush; and, on average, a painter who paints for 5 h in a day lifts the bucket about 120,140 times.

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.

Occupational stress and biomechanical risk in a high fashion clothing company.

Psychosocial discomfort may amplify job-related risk factors. The aim of this study is to evaluate job stress in a high fashion clothing company with upper limb biomechanical overload due to repetitive and forceful manual activities. Biomechanical risk was analyzed and in part reduced using the OCRA Check list. A total of 518 workers (433 females and 85 males) were investigated to determine anxiety (by STAI 1 and 2), occupational stress (using the Italian version of the Karasek Job Content Questionnaire) and perception of symptoms. Final biomechanical assessment did not reveal high risk jobs, except for cutting. Although the perception of anxiety and job insecurity was within the normal range, all the workers showed a high level of job strain (correlated with the perception of symptoms) due, probably, to very low decision latitude. It was suggested that job strain may increase the perception of symptoms. Moreover, the result of this study indicates that musculoskeletal overload has to be further analyzed since its low level is not in agreement with the level of discomfort due to the repetitive tasks.

Analysis of occupational stress in a high fashion clothing factory with upper limb biomechanical overload.

PURPOSE: To study job stress and upper limb biomechanical overload due to repetitive and forceful manual activities in a factory producing high fashion clothing. METHODS: A total of 518 workers (433 women and 85 men) were investigated to determine anxiety, occupational stress (using the Italian version of the Karasek Job Content Questionnaire) and perception of symptoms (using the Italian version of the Somatization scale of Symptom Checklist SCL-90). Biomechanical overload was analyzed using the OCRA Check list. RESULTS: Biomechanical assessment did not reveal high-risk jobs, except for cutting. Although the perception of anxiety and job insecurity was within the normal range, all the workers showed a high level of job strain (correlated with the perception of symptoms) due to very low decision latitude. CONCLUSION: Occupational stress resulted partially in line with biomechanical risk factors; however, the perception of low decision latitude seems to play a major role in determining job strain. Interactions between physical and psychological factors cannot be demonstrated. Anyway, simultaneous long-term monitoring of occupational stress features and biomechanical overload could guide workplace interventions aimed at reducing the risk of adverse health effects.

Daily intake of Lactobacillus casei Shirota increases natural killer cell activity in smokers.

Dietary probiotics supplementation exerts beneficial health effects. Since cigarette smoking reduces natural killer (NK) activity, we evaluated the effect of Lactobacillus casei Shirota (LcS) intake on NK cytotoxic activity in male smokers. The double-blind, placebo-controlled, randomised study was conducted on seventy-two healthy Italian blue-collar male smokers randomly divided for daily intake of LcS powder or placebo. Before and after 3 weeks of intake, peripheral blood mononuclear cells were isolated and NK activity and CD16⁺ cells' number were assessed. Daily LcS intake for 3 weeks significantly increased NK activity (P < 0.001). The increase in NK activity was paralleled by an increase in CD16⁺ cells (P < 0.001). Before intake, NK cytotoxic activity inversely correlated with the number of cigarettes smoked (R - 0.064). LcS intake prevented the smoke-dependent expected NK activity reduction. The analysis of the distribution of changes in smoke-adjusted NK activity demonstrated that the positive variations were significantly associated with LcS intake, while the negative variations were associated with placebo intake (median value of distributions of differences, 20.98 lytic unit (LU)/107 cells for LcS v. - 4.38 LU/107 cells for placebo, P = 0.039). In conclusion, 3 weeks of daily LcS intake in Italian male smokers was associated with a higher increase in cytotoxic activity and CD16⁺ cells' number in comparison to the placebo intake group.

Effects of palladium nanoparticles on the cytokine release from peripheral blood mononuclear cells of palladium-sensitized women.

OBJECTIVE: To investigate the effects of palladium (Pd) nanoparticles on cytokine release from peripheral blood mononuclear cells (PBMCs) of control or Pd-sensitized nonatopic women. METHODS: TNF-α, IL-5, IL-10 and IFN-γ release and/or expression from PBMCs incubated in presence of 5 to 10 nm Pd nanoparticles or Pd salt (potassium hexachloropalladate) were determined by enzyme-linked immunosorbent assay and reverse transcription-polymerase chain reaction analysis. Transmission electronmicroscopy was performed. RESULTS: In lipopolysaccharide-stimulated PBMCs from controls, Pd salt inhibited IFN-γ and IL-10 release, whereas Pd nanoparticles enhanced IFN-γ release and inhibited TNF-α secretion. In lipopolysaccharide-stimulated PBMCs from Pd-sensitized women showing high IFN-γ release, Pd nanoparticles inhibited TNF-α release and Pd salt IL-10 release. TNF-α and IFN-γ release and messenger RNA expression were correlated. Transmission electronmicroscopy demonstrated uptake of nanoparticles in the endocytic compartment and activation of autophagy. CONCLUSIONS: Palladium ions and nanoparticles exert different effects in vitro on the expression and release of cytokines.

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.

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.

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.

Environmental and occupational stress and autoimmunity.

The immune system and the neuroendocrine system machinery modulate each other, including life events-induced stresses and interpersonal conflicts, promoting the synthesis of proinflammatory cytokines, overproduction of which influence behaviour. In addition, the balance of systemic and local pro-inflammatory cytokines to systemic and local anti-inflammatory cytokines, is impaired to such an extent that, in genetically-predisposed individuals, this aberrancy may lead to autoimmune diseases. Occupational stress likely influences their onset. For example, subclinical autoimmune hypothyroidism has been identified in numerous shift-workers of an Italian hospital. Such a threat impacts the policy of health surveillance of the workers and requires dedication of further studies to the relationship between occupational stress and autoimmunity.

Inhibitory effects of cadmium on peripheral blood mononuclear cell proliferation and cytokine release are reversed by zinc and selenium salts.

Zinc (Zn) and selenium (Se) exert regulatory activities on immune functions, while cadmium (Cd) is an immunotoxic agent. The object of this study was to detect effects of 10(-4), 10(-5), and 10(-6) M Cd sulphate, Zn sulphate, and sodium selenite, and their combinations on human peripheral blood mononuclear cell (PBMC) proliferation and IFN-gamma and TNF-alpha production. Only 10(-5) M Zn sulphate significantly enhanced spontaneous PBMC proliferation, which was unaffected by the other salts. At 10(-4) and 10(-5) M, Cd sulphate exerted a dose-response inhibitory action on phytohemagglutinin- (PHA-) stimulated PBMC proliferation and cytokine release, while 10(-4) M and 10(-5) M Zn sulphate and 10(-5) M sodium selenite induced a stimulatory effect on both proliferation and cytokine release; 10(-4) M sodium selenite enhanced only the PBMC proliferation; at 10(-6) M, none of the salts changed the PHA-stimulated immune activity. Moreover, 10(-4) and 10(-5) M Zn and 10(-5) M Se strongly upregulated IFN-gamma (a Th1 cytokine) release, even in presence of 10(-5) M Cd, and reduced the inhibitory effects of Cd on PBMC proliferation and TNF-alpha release. This study confirms that Zn and Se both strongly enhance cytokine release induced by mitogenic stimulation, showing also that Zn acts with a broader range of concentrations than Se. This suggests that dietary excess of Se may not have beneficial effects.

Different effects of platinum, palladium, and rhodium salts on lymphocyte proliferation and cytokine release.

The effects of graded concentrations of Pt, Pd, and Rh salts on spontaneous and PHA-stimulated peripheral blood mononuclear cell (PBMC) proliferation and IFN-gamma, TNF-alpha, and IL-5 release were the focus of this study. Spontaneous PBMC proliferation was inhibited by all 10(-4) M salts (with the exception of PtCl2), while it was enhanced by 10(-5) M PtCl2 as well as by 10(-5) and 10(-6) M (NH4)2[RhCl6] and RhCl3 (but not by 10(-7) M salts). Pt, Pd, and Rh compounds showed similar effects on PHA-stimulated PBMC proliferation and cytokine release; however, the effects on IFN-gamma release were stronger. Thus, 10(-4) and 10(-5) M (NH4)2[PtCl6] and 10(-4) M (NH4)2[PtCl4] inhibited the PHA-stimulated immune activity; 10(-4) M PtCl2 did not exert activity, while 10(-6) M (NH4)2[PtCl6] and 10(-5) and 10(-6) M (NH4)2[PtCl4] and PtCl2 enhanced PBMC proliferation and/or cytokine release. (NH4)2[PdCl6] showed stronger dose-related inhibitory effects (present also at 10(-7) M concentration) on PHA-stimulated proliferation and cytokine release than (NH4)2[PdCl4], PdCl2, or Rh salts; the inhibitory activity of (NH4)2[RhCl6] was slightly higher than that of RhCl3. In conclusion, this study shows that: (a) the immune capacity of Pt, Pd, and Rh depends on speciation; (b) low concentrations of Pt salts stimulate spontaneous and PHA-stimulated immune responses; (c) the in vitro activity of Pd compounds (which are only inhibitory) is higher than that of Pt and Rh salts. These findings are consistent with the observations that sensitization and allergic contact dermatitis in response to Pd are increased in the general population, although the roles of cross-sensitization to Pd and Ni are difficult to determine.

In vitro effects of platinum compounds on lymphocyte proliferation and cytokine release.

In vitro immune effects of Pt compounds of occupational and/or environmental importance, or those used in cancer treatment were studied. Spontaneous and PHA-stimulated proliferation of peripheral blood mononuclear cells (PBMC) and in vitro release of TNF-alpha, IFN-gamma, and IL-5 were assessed in presence of high and very low concentrations of Pt salts: 10(-4) and 10(-7) M (NH4)2[PtCl6], (NH4)2[PtCl4], PtCl4, PtCl2, Na2PtI6, and cis-diaminedichloroPt (CisPt). Spontaneous and PHA-stimulated PBMC proliferation were both inhibited by 10(-4) M (NH4)2[PtCl6] and (NH4)2[PtCl4], while only PHA-stimulated proliferation was inhibited by 10(-4) M CisPt, without significant effects of the other Pt salts. TNF-alpha release from PBMC was reduced by 10(-4) M (NH4)2[PtCl6] and INF-gamma release was reduced by 10(-4) and 10(-7) M hexa- and tetrachloroplatinate and 10(-4) M Na2PtI6, but not by other Pt salts. IL-5 release (related to the Th2 immune response) was inhibited by 10(-4) M (NH4)2[PtCl6], (NH4)2[PtCl4] and Na2PtI6, but it was enhanced by both 10(-4) and 10(-7) M PtCl4. PtCl2 did not influence the immune effects. The study shows Pt salts have immune effects and their potency is ranked in the following order: (NH4)2[PtCl6] > (NH4)2[PtCl4] > Na2PtI6 and CisPt > PtCl4 > PtCl2. These results indicate that certain Pt salts affect lymphocyte proliferation and cytokine release. The intracellular mechanisms responsible for such effects have not been identified.

In vitro effects of nickel-sulphate on immune functions of normal and nickel-allergic subjects: a regulatory role for zinc.

Nickel hypersensitivity represents a very common human disease state, mainly occurring in females, defined as allergic contact dermatitis. Ni is a transition metal whose activity may be modulated by congeners. Zinc, an essential component for living organisms, has been shown to counteract Ni effects in patients with Ni hypersensitivity. We analysed immune responses to both Ni and Zn in healthy subjects and patients with allergic contact dermatitis to Ni. Our in vitro results show that Ni modulates surface receptors expression, reduces phytohemagglutinin (PHA)-driven lymphoproliferation, and upregulates some proinflammatory cytokines production, including interferon (IFN)-gamma. Zn also induced CD4+ lymphocyte proliferation, but it abolished or reduced most Ni-mediated effects. Our data are consistent with the hypothesis that Zn and Ni, as part of the heavy transition metals, may exchange roles in immune-mediated phenomena leading to expression of allergic contact dermatitis.

Prevalence and risk factors for latex-related diseases among healthcare workers in an Italian general hospital.

Latex allergy has become an occupational hazard among healthcare workers. Atopy and degree of exposure have been recognized as predisposing factors for latex sensitization. We investigated the prevalence of latex allergy and the potential risk factors for latex sensitization, by distributing a questionnaire to 284 employees of a general hospital in central Italy. We collected information about occupational history, including specific tasks performed; time of first exposure to latex gloves; number of pairs of gloves; and duration of daily exposure. We also investigated the interval between first exposure and onset of symptoms, as well as the exact circumstances of their appearance. We evaluated pre-existing rhinoconjunctivitis, asthma, atopic and contact dermatitis, and allergies to drugs and foods using prick and patch tests. Latex allergy was established by means of skin-prick test, specific IgE, patch-test, and latex-glove-wearing test. This survey documented a high prevalence of symptoms related to the use of latex (47%) among the hospital staff, demonstrable sensitization to latex was considerably lower (12%), though strongly associated to atopy and duration of occupational exposure. Despite non-specificity, validated questionnaires constitute the most useful means to implement health surveillance and prevention of latex-related diseases among healthcare workers.

Effects of resveratrol on lymphocyte proliferation and cytokine release.

Resveratrol, synthesized in dietary plants and contained in wine, has been reported to play a beneficial role in certain cardiovascular regulatory mechanisms and to inhibit carcinogenesis by activating immune and inflammatory responses and apoptosis. The object of this study was to elucidate the "in vitro" effects of different concentrations of resveratrol (10(-4), 10(-5), and 10(-7) M) on human peripheral blood mononuclear cell (PBMC) proliferation and cytokine release. Spontaneous PBMC proliferation was unaffected by resveratrol, while the compound at 10(-4) M inhibited (69%) the PHA-stimulated PBMC proliferation. The proliferation stimulation index (ie, the ratio of PHA-stimulated PBMC proliferation/spontaneous PBMC proliferation) of cultures containing 10(-4) M resveratrol was very low in relation to the control, while the proliferation stimulation index values at 10(-5) and 10(-7) M were similar and slightly higher (without statistical significance), respectively. At 10(-4) M, resveratrol strongly inhibited PHA-stimulated IFN-gamma and TNF-alpha release from PBMC, but it did not cause inhibition at 10(-5) or 10(-7) M. The concomitant immune effects of resveratrol on PBMC proliferation and release of IFN-gamma and TNF-alpha may be explained by an inhibitory effect on transcription factor NF-kappaB. This study suggests that resveratrol, which is typically present in red wine at about 10(-5) M, is unlikely to cause inhibitory immune effects. However, a stimulatory effect of low concentrations of resveratrol on the immune system cannot be excluded.

In vitro effects of vanadate on human immune functions.

Vanadium (V) is an element with wide industrial applications and environmental release. The object of this study was to determine the in vitro effects of high (10(-4) M) and low (10(-7) M) concentrations of sodium metavanadate (NaVO3) on cultured peripheral blood mononuclear cell (PBMC) proliferation, cytokine release, CD expression, and granulocyte O2- production. At 10(-4) and 10(-7) M, NaVO3 did not modify PBMC proliferation in the absence of phytohemagglutinin (PHA). On the other hand, 10(-4) M NaVO3 reduced by -25% the PBMC proliferation in PHA-stimulated cultures, with a significant reduction of the stimulation index (SI) of blastogenesis. Moreover, 10(-4 M NaVO3 significantly reduced the release of IFN-gamma by PHA-stimulated PBMCs, and 10(-7) M NaVO3 significantly enhanced the release of TNF-alpha. In addition, IL-5 release was significantly inhibited by high concentration of sodium metavanadate and significantly enhanced by low concentration of NaVO3. Neither 10(-4) nor 10(-7) M NaVO3 modified the expression of CD3+, CD4+, CD8+, or CD56+ in PHA-stimulated and unstimulated lymphocytes. Finally, 10(-4) M NaVO3 reduced the granulocyte production of O2- by about 70%, while 10(-7) vanadate reduced its production to a lesser extent. These results show that 10(-4) M NaVO3 exerts inhibitory effects on PBMCs, while at 10(-7) M it exerts a stimulatory action with a slight shift of the immune response towards a Th2-type response. This investigation suggests that environmental V can have important effects on the human immune system.