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Biomedical subjects

L Ambrosi

Publications and source records attributed to L Ambrosi.

At least 73 records · Page 4Linked to original sources

[Fatiguing work, aging and health: a cross-sectional study of a group of anesthesiologists].

A cross-sectional study was carried out to verify if work as an anaesthetician-reanimator can be considered as a fatiguing job. An anonymous self-administered questionnaire was utilized to obtain information about the general characteristics of the subjects, job organization, human relations, perceived risks and previous diseases; 1438 questionnaires were examined. The results of the study showed that in anaesthetist-reanimator: organic diseases do not occur earlier than expected; perception of the emotional aspects related to the particular occupation is low; the group relationships are difficult, on both horizontal and vertical levels, and these difficulties increase work-stress and hinder its management; age influences the occurrence of both arthritic and stress-related diseases; there is an association between jobs dissatisfaction and stress disorders; all the causal variables considered, evaluated as a group, constitute a heavy physical load, that leads to risk of stress related diseases.

Age Factors↗

[Immunologic effects of exposure to low levels of inorganic mercury].

OBJECTIVE: The immune system is a target for the toxic effects of inorganic mercury, both in humans and animals. In humans it has been observed that occupational and environmental exposure to inorganic mercury may cause both clinical (autoimmunity, hypersensitivity) and subclinical effects (cellular and humoral immunologic variable modifications). To obtain a better definition of these effects with respect to the exposure levels, a multicentre study was performed on 117 workers exposed to very low doses of inorganic mercury and 172 subjects from the general population of the same geographical area with environmental exposure to mercury from dental amalgams and dietary fish intake. RESULTS: The white blood cell count was included in the normality range for all subjects and there was no difference between exposed and non exposed subjects. The immunologic variables studied showed an increase of the CD4+ and CD8+ number in exposed workers compared to non-exposed subjects, with a statistically significance only for CD4+, while no difference was observed regarding CD4+, CD8+, NK+ percentage and CD4+/CD8+ ratio. A significative decrease of serum IL-8 and an inverse correlation between serum levels of this cytokine and HgU were observed in exposed workers compared to non exposed subjects. No association between immunologic variables and both dental amalgams and dietary fish intake was found in subjects not occupationally exposed to inorganic mercury. DISCUSSION: The decrease in IL-8 serum levels observed in exposed workers might suggest an immunosuppressive effect of occupational exposure to very low doses of inorganic mercury. This result suggests the need to revise of current HgU BEI after further definition of its prognostic significance.

Adult↗

[Promoter effect of mercury chloride and methyl-mercury on human keratinocytes in culture].

Mercury has received considerable media focus because it is present in dental amalgams and seafood. There is potential exposure in gas meters, thermometers and fluorescent lamps workers. To evaluate its possible epigenetic carcinogen effect, cultures of human keratinocytes were treated with increasing doses of HgCl2 for 30 min, 24 h and of CH3HgCl for 24 h, respectively. The red neutral method was used to evaluate the doses of HgCl2 and CH3HgCl which had no cytotoxic effect. Then, the dye transfer method was used to investigate the gap junctions-mediated intercellular communication (GJIC). Cells were microinjected with Lucifer Yellow CH by using the Eppendorf Apparatus and the Leica inverted microscope. After 30 min incubation at the concentration of 10 microM, HgCl2 did not exert inhibition of GJIC. Conversely, after 24 h at the concentration of 10 nM, HgCl2 inhibited GJIC. Incubation with CH3HgCl at the concentration of 250 nM for 24 h reduced the number of fluorescent cells, thus denoting a inhibition of GJIC. Taken together our data demonstrated that: i) HgCl2 and CH3HgCl exerted an inhibitory effect upon GJIC; ii) HgCl2 resulted to inhibit GJIC at concentrations 25 folds lower than CH3HgCl. Further studies will be addressed to evaluate whether the reversal of GJIC inhibition could be obtained by withdrawal of toxic substance, or by the addition of a GJIC activator like the retinoic acid. Finally to shed light on the possible effect of mercury derivates at the transcriptional or translational levels, the expression profile of the connexin 43 gene after HgCl2 and CH3HgCl exposure of cultured human keratinocytes will be investigated.

Cell Communication↗

[Effects of noise on cortical mechanisms involved in the development of linguistic sounds].

So far studies about noise effects on speech perception have been focused on the development of hearing loss and other related pathologies. However, behavioral findings indicate that speech perception and intelligibility are disrupted in presence of noise in certain clinical groups in a way that is unpredictable on the basis of the audiogram performed in silence. This observation suggests that even soft noise can modify the cerebral mechanisms underlying speech information processing. Confirming the behavioral results, electric and magnetic brain measurements showed that noise presented to healthy subjects decreases the amplitude and increases the latency of brain responses to speech sounds. Recently, further experimental data allowed us to have a deeper knowledge of the neural mechanisms interventing in difficult listening conditions. In particolar, speech sounds presented in noisy background evoke bioelectric responses in neural populations located in the right cerebral hemisphere, that otherwise would not be activated. These findings can in future contribute to unveal new aspects of the noise pathology and its assessment in an early pre-clinical stage.

Cerebral Cortex↗

[Implementation of parliamentary act D. Lgs 25/02 and definition of "moderate risk"].

This paper describes the position of the Joint Working Group of the Italian Association of Industrial Hygienists (AIDII), the Italian Society of Occupational Health and Industrial Hygiene (SIMLII) and the Italian Society of Toxicology (SITOX) on "Analysis of Parliamentary Act D.Lgs 25/02 and role of the Scientific Societies in the definition of Limit Values". The positive aspects of the new law which implements the European Directive 98/24 are discussed, including the abolition of the rigid periodicity of medical examinations as stated by the old rule D.P.R. 303/56. The Authors also address various parts of the law which appear to be unclear and controversial and highlight the expected difficulties arising for the employers and the safety and health professionals during the application of this new piece of legislation. Moreover, a number of discrepancies are noted between the new Italian law and the original Directive or other current Italian rules such as i. the translation of the term "slight risk", as from the original Directive, into "moderate risk", and the resulting non compulsoriness of health surveillance and biological monitoring of the workers in presence of a "moderate risk", ii. the concurrent exclusion, under the same circumstances, of the occupational physician from risk assessment procedures and iii. the upward modification of the previously established (D.Lgs 277/91) occupational exposure limits for lead. Moreover, the Authors examine and criticize--both in semantic and in toxicological terms--a recent proposal for the definition of "moderate risk" made by an ad hoc Consulting Committee of the Labour Ministry, in which the term "moderate" has been interpreted either as "low" or as "irrelevant for health effects", clearly two very different meanings. Besides, it would be inappropriate to define the conditions of a moderate risk based only on the level of exposure to the chemical (expressed as a fraction of the corresponding limit value), without considering the two other components of risk assessment for that chemical (hazard and susceptibility). Even worse would be the use of simplified models based on "algorithms", which might be useful in a preliminary phase of risk assessment, but easily could lead to an under- or over-estimation of risk, particularly when used by non professionals. In conclusion, the Working Group recommend that the new law be amended in order to clarify its most controversial aspects, whose misinterpretation could severely jeopardize the protection of the workers' safety and health at work.

Humans↗

[Ocular hypertension in radiologists and radiology technicians].

Ionizing radiations (IR) produce changes in the eye and, above all, in the lens. Several studies on radiotherapy in neoplastic diseases and dangerous nuclear accidents like Chernobyl have indicated the percentage and the exposure level at which the eye becomes the target organ of IR. The aim of the study was to establish the association between ocular tension and low-level IR exposure. The incidence of ocular hypertension in the general population is about 1-2% in persons aged 30-40 years and 10% in the 70-80 years age group; the frequency of glaucoma is 0.2-0.5% in persons aged 50-55 years and 2% in those aged 70 years and over; after 15 years of disease, conversion from ocular hypertension to glaucoma is observed in 40% of the cases. We examined 128 subjects occupationally exposed to IR (42 radiologists and 86 radiology technicians) and 130 non-exposed. For each subject we recorded age, length of employment, job titles, dosimetry, ocular tension, refraction and motility impairments. The data obtained from a complete ophthalmologic test was analyzed by the t-Student test, Chi-square and Pearson's test. The ocular tension of 33 occupationally exposed subjects and 2 non-occupationally exposed subjects was higher than the cut-off value of 18 mmHg. There was no analogy between age distribution of ocular hypertension in the groups under study and the general population. There seems to have been a relationship between ocular tension and job titles since a higher incidence was observed among the radiology technicians than among the radiologists and also in the 30-40 years age class.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

[Excellency accreditation by the Italian Society of Occupational Medicine and Industrial Hygiene (SIMLII)].

BACKGROUND: The Italian Society for Occupational Health and Industrial Hygiene (Società Italiana di Medicina del Lavoro e Igiene Industriale)--SIMLII--has taken a systematic approach to the topic of permanent education of occupational health physicians over the last 4 years, developing its own project entitled "SIMLII Permanent Education and Excellency Accreditation". OBJECTIVES: The SIMLII Project, which is addressed to occupational health specialists and physicians authorized under Law 277/91, art. 55, is based on the participation of "obligatory" and "non-obligatory" educational activities and on assessment of professional activity. "Obligatory" educational activities are events organized directly by SIMLII and consist of a detailed study of the guidelines concerning specific occupational health topics. The "non-obligatory" events are those regarding occupational health that the physician chooses voluntarily, with accreditation by the Ministry of Health and/or by SIMLII. The occupational health physician who enrolls for the 3-year course must obtain a total of 180 SIMLII training credits in the 3 years (60 per year). Assessment of activity performed is made at the end of the 3 years of training according to criteria set out by SIMLII and approved by the membership, via a self-administered questionnaire. METHODS AND RESULTS: The SIMLII Project has laid great emphasis on drawing up guidelines on topics specific for occupational health. These guidelines are developed by groups of experts selected by SIMLII and deal with topics that the occupational health physician most frequently encounters in the course of his/her professional activity. There are 405 participants in the first 3-year training course covering the whole of Italy. The aim of the Italian Society for Occupational Health and Industrial Hygiene, via excellency accreditation and drawing up of guidelines for particularly important topics, is to provide useful tools to satisfy the training requirements of its membership, to improve the quality of professional services and to emphasize the uniqueness and specific nature of occupational health within the medical specialties.

Accreditation↗

[Assessment of heart rate variability (HRV) as a stress index in an emergency team of urban police].

Stress is usually defined as the experience of negative events or the perceptions of distress and negative affect that are associated with the inability to cope with them. The parameter most suitable for large-scale field studies is the determination of endocrine activity by measurement of salivary cortisol. The aim of the present study is to identify the presence of sources of stress in an emergency team of urban police and to objective such stress using the PSS (Professional Stress Scale) test and bioumoral markers as salivary cortisol and interleukin 1 beta (IL1-B). Moreover it will be determined the Heart Rate Variability (HRV) that is able to mirror the sympathetic-parasympathetic balance. We studied 30 policemen who belonged to an emergency team. Thirty policemen made cardiologic exams as ECG, Heart Eco-doppler and Holter Ecg during the work and during the holiday. Particularly we studied HRV using frequency-domain based HRV measures. The results were evidenced as the differences of the spectral power. As control we used the same subjects during the holiday. T test was performed to evaluate the differences between the means, the Chi Square's Test was performed to determine the statistically significant association between PSS subscales, HRV, salivary cortisol and IL1-B concentrations. The study of HRV demonstrated a statistically significant association between HRV parameters during the holiday, salivary cortisol concentrations and PSS test. IL1-B, instead, was not associated with HRV parameters. Several precedent studies agree with our results. Our study has suggested a work related stress in urban police employed in an emergency team. We might conclude that salivary IL1-B and cortisol are useful markers of stress. The study of HRV parameters gave evidence that LF/HF during the holiday is a useful marker of work stress, because it correlated with cortisol difference during the work. Conclusively we can believe that the HRV parameters evaluated during the work are useful as confront, instead the HRV parameters during the holiday are surest indexes of work stress. Probably the effect of stress on the heart aren't present during the work because the work experience reduces these effects, they appear during the holiday when the imagination could make the conflicts or the problems more complex than they are. It might be useful to repeat this study after some structure organizational modifications and after training that will teach the workers coping strategies. If we consider only the bioumoral and PSS results, we might conclude that the stress discovered in this study is not hazardous for the health when the workers have adequate holidays, but if we evaluate the HRV parameters, we have believe that, for a heart health, it's necessary either to increment the holidays or, it can appear paradoxical, to work again.

Adult↗

[Occupational asthma and biological damage: adequate compensation?].

The evaluation of the damage to biological and relational capacities of the subject is the novel approach of the Italian Insurance Regulation Decree N(o) 38/2000 for compensating occupational asthma (OA). In this study we aimed to apply retrospectively the novel rating system to mild OA. From a data base of 201 diagnosis of OA collected in the 1987-97 decade 85 eligible consecutive cases of mild asthma according to the criteria of NIH/WHO guidelines on asthma were studied. Records on compensation were documented for 41 subjects. The average difference between novel scales and the actual rating individually assessed by Italian National Agency for compensation through criteria used at that time was 45.6 +/- 20%. The average difference between novel scales and rating calculated with guidelines considering the measurement of non-specific bronchial hyperreactivity developed by international experts and American Thoracic Society, endorsed by American Medical Association, was 41.5 +/- 12%. Within the actual rating individually assessed with previous Italian Insurance criteria no significant relationship (r=-0.20, p=0.2) was shown with bronchial responsiveness to methacoline expressed as provocative dose causing a 20% fall in FEV1 (PD20FEV1 microg of mch). A significant (p<0.05) relationship was observed with age at the time of OA diagnosis (r=0.37, p=0.017) and with duration of exposure (r=0.34, p=0.034). This study suggests that scales of the Insurance Regulation Decree N(o) 38/2000 grading mild OA underevaluate biological damage/impairment with reference both to previous practice in Italy and to international criteria guidelines. Among the parameters of evaluation methacoline challenge should be considered an adequate tool in measuring biological damage in OA for medicolegal purpose.

Asthma↗

[Survey on educational needs in occupational medicine in Italy].

The importance to correctly address continuing education among occupational health professionals in Italy has been particular in the focus of the Scientific and Professional Medical Community also in consideration of the recent regulations implemented in the field of Continuing Medical Education (CME). The Italian Society of Occupational Medicine recently developed an advanced programme of Continuing Medical Education for Occupational Physician. In order to correctly asses the education needs and collect valid information of Occupational Physicians in Italy we administered a target questionnaire among a group of them. The results are analyzed and discussed.

Adult↗

The study of gap junctional intercellular communication in keratinocytes as screening of promoter effect induced by industrial and environmental toxic substances.

BACKGROUND: Disordered functioning of gap junctions between normal and initiated cells has been proposed as one possible mechanism of tumour promotion. Many putative carcinogens such as peroxisome proliferators, are known to activate various signal transduction mechanisms and modulate gap junctional intercellular communication (GJIC). They act as tumour promoters on pre-existing "initiated" cells, rather than as genotoxic initiators. OBJECTIVES: The aim of this article is to provide a screening-tool to evaluate the promoter carcinogen effect of environmental and occupational chemical contaminants, focusing on their ability to alter GJIC. METHODS: GJIC was investigated in serum-free cultured primary human keratinocytes, by directly evaluating the intercellular transfer of a microinjected fluorescent dye (Dye transfer). The expression of caspase 3, which is the ultimate target to be activated of both mitochondrial- and non-mitochondrial-linked pro-apoptotic pathways, was evaluated using Reverse Transcriptase-Polymerase Chain Reaction (RT-PCR). RESULTS: Mercury chloride (10 nM), mono-methyl Mercury (250 nM) and Trichloroethylene (500 I1M) were shown to significantly inhibit GJIC. Conversely di-methyl mercury, lead acetate and epichloridine had no effect on GJIC. All Trans Retinoic Acid completely reversed the inhibitory effect on GJIC induced by HgCI2 but not that induced by mono-methyl mercury and trichloroethylene. The result of a RT-PCR assay on total RNA cell extract showed that treatment of keratinocytes with 10 nM HgCl2 resulted in a decrease of the pro-apoptotic caspase 3 expression. CONCLUSIONS: In this work a protocol is designed to study gap junction intercellular communication in primary cultures of human keratinocytes which could be used as a reliable screening tool to test the promoter carcinogen effect of various environmental and occupational contaminants.

Air Pollutants, Occupational↗

[Symptoms and musculo-skeletal changes among personnel of the State Police exposed to mechanical risk].

The aim of this present study was to inquire about spine morfo-functional alterations among policemen with jobs regarded as potentially hazardous, in order to identify preclinical alterations of column and to plan adequate preventive measures. A physiopathologic and working anamnesis was carried out by means of questionnaire about personal data, jobs, reported rachidian symptomatology and presence of orthopedic diseases, given to policemen on duty in Bari. Every chosen worker was subject to orthopedic and neurological examination, radiography of column, Formetric tridimensional examination, telethermography of spine. We stratified the sample on the basis of age and job. Under the jobs we individuated 4 biomechanical hazardous activities, performed separately or together: driving motorcycle, driving car, flying helicopter, video terminal use. The whole sample, formed by 211 subjects, all male, had the average age of 39 years (Standard Deviation: +/- 4). About the reported rachidian symptomatology, only 41 (17, 98%) subjects were asymptomatical, contrary to clinical results, that were normal in almost the entire sample, with the exception of 3 workers (1, 31%), who had neurological clinical alterations. Structural alterations were checked by radiography among 64, 9% of subjects. The Formetric examination found alterations in different tract of rachis, also coexiting between each other. The telethermographic changes affected 63,99% of the sample and involved especially the lumbar tract (38,86%), dorsal region (18%) and cervical zone (7,1%). The relative frequency of dorsal tract increased with growing of age. The morfo-functional changes of the sample seem to depend rather on the performed job, than on degenerative process of age, partly because the average age of the sample is not much elevated and because the enlistment in Italian Police Force is subordinated to verification of optimum conditions, also characterized by absence of anomaly of column. The absence of clinical alteration, in contrast to reported rachidian symptomatology by 82,02% of subjects and with discovered objectivity, demands more clinical attention in presence of symptomatology and proposes supplementary non-invasive techiniques of investigation, as the telethermography and the formetric tridimensional examination.

Adult↗

[In vitro mucociliary clearance: observations in subjects exposed to acute inhalation of nitrous vapors].

Acute inhalation of nitrous vapours did not cause any damage to the respiratory apparatus detectable via spirometric or X-ray tests in the four workers who were actually exposed and kept under observation during the two months following the explosion of a tank containing nitric acid. However, measurement of the coefficient of relative transport speed in vitro of tracheo-bronchial secretions revealed alterations of the mucus related to specific situations, such as during acute inhalation of nitrous vapours and upon resuming work. The coefficient of relative speed, obtained with the in vitro technique on the palate of the frog, thus proved to be reliable in monitoring irritation of the mucus secreting apparatus of workers accidentally exposed to acute inhalation of nitrous vapours.

Adult↗

[Total and partial O2 and CO2 ductances in workers exposed to inhalation of cement-asbestos].

The aim of the study was to assess the efficiency of the respiratory system in ensuring the correct dynamics of respiratory gases in subjects chronically exposed to the inhalation of asbestos-cement dust but not yet suffering from parenchymal asbestosis, via measurement of total and partial O2 and CO2 ductance coefficients (Du). Two groups of male workers of working age were selected, the first consisting of 22 workers employed on the manufacture of asbestos-cement products, the second consisting of 26 workers who had never been exposed to the inhalation of significant concentrations of occupational respiratory irritants. The two groups were comparable for age, smoking, and normal spirometric parameters for FVC, FEV1 and PEF, and were free of any type on interstitial lung disease according to ILO standards. In the exposed group, all O2 and CO2 ductance coefficients were significantly lower than in the non-exposed, except DuBCO2 (alveolar-capillary ductance for CO2). Measurement of O2 and CO2 lung ductances at rest thus revealed an impairment of the diffusion and of the interpulmonary exchange of blood and air in subjects chronically exposed to the inhalation of asbestos-cement dust. In the sample under study, such impairment preceded lung damage detectable by spirometric and radiological tests and was an obstacle not only to oxygen intake but also to the elimination of carbon dioxide.

Adult↗