Maxillary fungus ball: zinc-oxide endodontic materials as a risk factor.

The objective of this study was to demonstrate the correlation between endodontic treatment on maxillary teeth and fungus ball with inductively coupled plasma mass spectrometry measurement of zinc and other metals (barium, lead and copper) in fungus ball samples. Samples of normal maxillary mucosa were used as comparison. Metal concentration was also measured in several endodontic materials. A significant difference was found between the concentration of zinc and copper in fungus ball compared to normal mucosa. Metal distribution was more similar in fungus ball and in the endodontic materials tested than normal mucosa. The similar metal concentration in the endodontic materials and fungus ball suggests that endodontic materials play a role in the pathogenesis of fungus ball. Endodontic materials accidentally pushed into the maxillary sinus during endodontic treatments may play a crucial role. Dentists should be as careful as possible when treating maxillary teeth to avoid perforating the maxillary sinus floor; the use of zinc-free endodontic materials, as zinc is a metal that plays a pivotal role in fungus growth, should be encouraged.

Defining reference values of trace elements in the tear film: diagnostic methods and possible applications.

The study has been performed on tears of apparently healthy subjects who live and work in urban and rural areas, respectively. After the collection the following elements were investigated: chromium (Cr); arsenic (As); copper (Cu); zinc (Zn); selenium (Se); rubidium (Rb); barium (Ba); lead (Pb) and cobalt (Co). Significantly higher values of As were found in subjects living and working in rural areas as compared to those found in urban area residents (0.290 vs. 0.025; p<0.001). Conversely, Ba and Pb were significantly lower in rural area residents (1.10 vs. 2.50, p=0.027 and 1.70 vs. 1.10, p=0.057, respectively). Our data show that trace elements analysis in tears is possible; further studies could define if it could be a reliable biomarker in persons exposed to high concentration of trace elements due to working or environmental reasons.

[Biological monitoring of exposure to carcinogenic metallic elements and polycyclic aromatic hydrocarbons in four secondary metallurgical sectors]. / Monitoraggio biologico dell'esposizione ad elementi metallici cancerogeni e ad idrocarburi policiclici aromatici in quattro settori metallurgici secondari.

This cross-sectional study was aimed at evaluating in a large sample of male foundry workers the current exposure levels to carcinogenic compounds, including metallic elements [arsenic (As), beryllium (Be), cadmium (Cd), chromium (Cr), nickel (Ni)] and aromatic polycyclic hydrocarbons (PAH) by a biological monitoring approach, using validated biomarkers of exposure. Workers were recruited from 15 aluminium, copper alloy, electric steel and cast iron foundries and provided an end-of-shift urine sample to determine urinary concentrations of As, Be, Cd, Cr, Ni and 1-hydroxypyrene (1-OHP). Metallic elements were determined either by inductively coupled plasma mass spectrometry (Be, Cd and Cr) or by atomic absorption spectrometry (As, Ni), whereas 1-OHP was determined by high pressure liquid chromatography with fluorimetric detection. Most of the determinations fell within the laboratory's reference values. Age and lifestyle habits (smoking, alcohol, diet) played a significant interfering role.

[Reference values of urinary mercury in the Italian population]. / Valori di riferimento del mercurio urinario nella popolazione Italiana.

This paper shows the results of a polycentric study performed to assess the reference values of urinary mercury (U-Hg) in Italian population. 374 subjects from four Italian cities (Bari, Brescia, Genova e Siena) have been examined. A questionnaire on life style, dietary habits, occupational or environmental exposure to Hg and clinical history has been administered to every participant and number and surface of dental amalgams have been verified for all subjects. The determination of U-Hg has been performed on urinary extemporary samples by hydride generation atomic absorption method (HG-AAS); urinary creatinine has been determinated to reduce the intraindividual variability. U-Hg reference values were: 0.21-3.20 micrograms/g creat (5 degrees and 95 degrees percentile) and 0.12-6.04 micrograms/g creat (range). Moreover study results have shown that number and surface of dental amalgams, dietary fish intake and body mass index (BMI) influenced significatively U-Hg excretion. U-Hg reference values from this polycentric study resulted comparable to those assessed in other European countries, whereas the mean U-Hg observed in the referent Italian population was lower.

The relationship between stress protein induction and the oxidative defense system in the rat hippocampus following kainic acid administration.

The time and dose-dependent effects of kainic acid (KA) induced excitotoxicity on the oxidative defense system and the relationship to the induction of stress proteins were investigated in the rat hippocampus. Male Long-Evans rats were injected subcutaneously with 5.0, 7.5, or 10 mg KA/kg. Rats were sacrificed and the hippocampus removed and processed for biochemical and electrophoretic analysis. The activity of glutathione peroxidase (GPx) increased significantly at the 5 mg KA/kg dose, while malondialdehyde (MDA) levels significantly increased at 7.5 mg KA/kg when measured at 24 h. A dose of 10 mg KA/kg depleted significantly hippocampal glutathione (GSH) levels at 8, 16 and 24 h post-treatment while GPx activity was increased significantly at 2, 4, 8 and 16 hr post-treatment. The 10 mg KA/kg increased significantly hippocampal MDA levels at 2 h post-treatment and decreased significantly thereafter. The induction of stress proteins increased in a dose and time dependent manner. The expression of Hp72 and Hsp32 increased significantly at 16 h with a maximum induction observed at 24 h post-treatment. The data suggests that KA toxicity is mediated through the formation of reactive oxygen species resulting in alterations in the oxidative defense system. The expression of stress proteins following KA administration may reflect a concomitant but alternate response to excitotoxic events.