Health effects of occupational exposure to acrylamide using hemoglobin adducts as biomarkers of internal dose

OBJECTIVES: This study assessed the health effects of occupational acrylamide exposure using hemoglobin (Hb) adducts as biomarkers of internal dose. METHODS: Two hundred and ten tunnel workers exposed for about 2 months to a chemical-grouting agent containing acrylamide and N-methylolacrylamide underwent a health examination. Blood samples were drawn for the analysis of Hb adducts of acrylamide. Fifty workers claiming recently developed or deteriorated symptoms of the peripheral nervous system (PNS) were referred to a neurophysiological examination. Workers with Hb-adduct levels exceeding 0.3 nmol/g globin attended follow-up examinations 6, 12, and 18 months after exposure cessation. RESULTS: Forty-seven workers had Hb-adduct levels within the normal background range (0.02-0.07 nmol/g globin), while the remaining 163 had increased levels up to a maximum of 17.7 nmol/g globin. Clear-cut dose-response associations were found between the Hb-adduct levels and PNS symptoms. Thirty-nine percent of those with Hb-adduct levels exceeding 1 nmol/g globin experienced tingling or numbness in their hands or feet. A no-observed adverse effect level of 0.51 nmol/g globin was estimated for numbness or tingling in the feet or legs. For 23 workers there was strong evidence of PNS impairment due to occupational exposure to acrylamide. All but two had recovered 18 months after the cessation of exposure. CONCLUSIONS: Occupational exposure to a grouting agent containing acrylamide resulted in PNS symptoms and signs. The use of Hb adducts of acrylamide as a biomarker of internal dose revealed strong dose-response associations. The PNS symptoms were, however, generally mild, and in almost all cases they were reversible.     

Evaluation of Skin and Respiratory Doses and Urinary Excretion of Alkylphosphates in Workers Exposed to Dimethoate During Treatment of Olive Trees

This article describes a study of exposure to dimethoate during spraying of olive trees in Viterbo province in central Italy. Airborne concentrations of dimethoate were in the range 1.5 to 56.7 nmol/m³. Total skin contamination was in the range 228.4 to 3200.7 nmol/d and averaged 96.0%±3.6% of the total potential dose. Cotton garments afforded less skin protection than waterproof ones, which were in turn associated with higher skin contamination than disposable Tyvek overalls. Total potential doses and estimated absorbed doses, including their maxima, were below the acceptable daily intake of dimethoate, which is 43.6 nmol/kg body weight (b.w.). Urinary excretion of alkylphosphates was significantly higher than in the general population, increasing with exposure and usually showing a peak in the urine sample collected after treatment. Metabolite concentrations were influenced by the type of individual protection used: minimum levels were associated with the closed cabin and maximum levels with absence of any respiratory or hand protection. Urinary alkylphosphates showed a good correlation with estimated absorbed doses and are confirmed as sensitive biologic indicators of exposure to phosphoric esters.     

Experience at a branch center of the National HIV Protease Inhibitor Registry

In the present study we show our experience as one of the Centers (center 006) of the Italian Index of Protease Inhibitors (PI). In this multicentric, observational study we studied HIV-positive naive patients for antiretroviral therapy with protease inhibitors. From 8/1/97 to 31/1/98 in our department 64 patients were enrolled and followed up through an electronic medical sheet in order to evaluate efficacy, tolerability, toxicity and compliance of treatment with PI. Our results show a reduction in AIDS-related mortality and a decrease in AIDS defining diseases: in particular data show an increase in CNS pathologies in comparison with other opportunistic events. Moreover, in patients non complaints to therapy, the progression of the disease was more frequent. The side effects more frequently observed during PI treatment were hypertrigliceridaemia and lipodystrophy; gynaecomastia and hyperprolactinaemia were even present, perhaps as expression of direct metabolic action of HAART therapy.     

Acute and chronic viral hepatitis in HIV positive patients

In this study we evaluated the spreading of HBV, HCV, HDV and HIV among drug user patients. Spreading of hepatotropic viruses resulted high (HBV 84%, HCV 87%, HDV 7%), while spreading of HIV resulted relatively low (18%). During the period considered we did not observe any favourable effect of hepatotropic viruses on the progression of HIV infection, while the chronic evolution of acute viral hepatitis HBV related was high (90%) in HIV+ patients. HIV infection did not determine different histological findings in respect to HIV- patients with chronic hepatitis, HBV or HCV related     

Reference Values of Urinary Trans,trans-muconic Acid: Italian Multicentric Study

This article reports the results of a study, conducted in the framework of the scientific activities of the Italian Society for Reference Values, aimed at defining reference values of urinary trans,trans-muconic acid (t,t-MA) in the general population not occupationally exposed to benzene. t,t-MA concentrations detected in 376 subjects of the resident population in three areas of Italy, two in central (Florence and southern Tuscany) and one in northern Italy (Padua), by three laboratories, compared by repeated interlaboratory controls, showed an interval of 14.4–225.0 μg/L (5th–95th percentile) and a geometric mean of 52.5 μg/L. The concentrations measured were influenced by tobacco smoking in a statistically significant way: Geometric mean concentrations were 44.8 μg/L and 76.1 μg/Ll in nonsmokers (264 subjects) and smokers (112 subjects), respectively. In the nonsmoking population, a significant influence of gender was found when concentrations were corrected for urinary creatinine, geometric mean concentrations being 36.7 μg/g creatinine in males (128 subjects) and 44.7 μg/g creatinine in females (136 subjects). The place of residence of subjects did not seem to influence urinary excretion of the metabolite, although personal inhalation exposure to benzene over a 24-h period showed slightly higher concentrations in Padua and Florence (geometric means of 6.5 μg/m³ and 6.6 μg/m³, respectively) than in southern Tuscany (geometric mean of 3.9 μg/m³). Concentration of t,t-MA in urine samples collected at the end of personal air sampling showed little relationship to personal inhalation exposure to benzene, confirming the importance of other factors in determining excretion of t,t-MA when concentrations in personal air samples are very low.     

Ultrasound-guided endoscopic drainage, without radiological examination, in patients with neoplastic biliary obstruction. Preliminary results

AIM: Endoscopic stent insertion has become the preferred method for palliation of malignant biliary obstruction. Currently, endoscopic stent placement involves the use of contrast media and radiological equipment to achieve direct opacification of the biliary duct systems, and to determine the location and the extension of biliary obstruction. This report proposes a new combination of ultrasonography and biliary endoscopy, with endoscopic stent placement entirely performed under US-guidance. METHODS: US-guided stent placement was carried out in 8 patients. A guide-wire and a guiding-catheter were endoscopically introduced and identified, by US, the common bile duct across the stricture. Hydromer-coated polyurethane angled stents (10F) were finally inserted over the guide-wire/guiding-catheter by a pusher tube system. RESULTS: Successful stent insertion was achieved in all patients. There were no complications. Successful drainage, with substantial reduction in bilirubin level, was achieved in all patients (14.2+/-9.5 vs 4.2+/-2.9 mg/dl at 1 week). CONCLUSION: Endoscopic stent placement performed under US-guidance, is safe and effective. Further studies in a larger series, including more proximal strictures are suggested.     

Cross talk between growth factors and viral and cellular factors alters neuronal signaling pathways: Implication for HIV-associated dementia

HIV-associated dementia (HAD) is a serious neurological disorder affecting about 7% of people with AIDS. In the brain, HIV-1 infects a restricted number of cell types, being primarily present in macrophages and microglial cells, less abundant in astrocytes, and rarely seen in oligodendrocytes and neurons. Lack of a productive HIV-1 infection of neuronal cells suggests the presence of an indirect pathway by which the virus may determine the brain pathology and neuronal dysfunction seen in AIDS patients. Among the participants in this event, viral proteins including gp120 and Tat, along with host factors including cytokines, chemokines, and several signaling pathways have received considerable attention. In this article, we discuss the most recent concepts pertaining to the mechanisms of HIV-1-induced neuronal dysfunction by highlighting the interplay between signal transduction pathways activated by viral and host factors and their consequences in neuronal cell function.     

Can technical, functional and structural characteristics of dental units predict Legionella pneumophila and Pseudomonas aeruginosa contamination?

Legionella pneumophila and Pseudomonas aeruginosa are common colonizers of water environments, particularly dental unit waterlines. The aim of this study was to assess whether the technical, functional and structural characteristics of dental units can influence the presence and the levels of opportunistic pathogens. Overall, 42 water samples were collected from dental units in a teaching hospital in Palermo, Italy, including 21 samples from the 21 taps supplied by the municipal water distribution system and 21 samples from oral rinsing cups at 21 dental units. L. pneumophila was present in 16 out of 21 water samples (76.2%) from dental units, and the median concentration was higher in samples from oral rinsing cups than in those from taps (P < 0.001). P. aeruginosa was equally distributed in water samples collected from oral rinsing cups and from taps. Some characteristics of dental units (age, number of chairs per room, number of patients per day and water temperature) were slightly associated with the presence of P. aeruginosa, but not with contamination by L. pneumophila. Our experience suggests that L. pneumophila is frequently detected in dental units, as reported in previous studies, whereas P. aeruginosa is not a frequent contaminant. As a consequence, microbiological control of water quality should be routinely performed, and should include the detection of opportunistic pathogens when bacterial contamination is expected.