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C Minoia

Publications and source records attributed to C Minoia.

At least 19 recordsLinked to original sources

Assessment of reference values for mercury in urine: the results of an Italian polycentric study.

The results of a polycentric study to assess the reference values of urinary mercury (U-Hg) in four Italian cities are presented. A total of 383 subjects were selected on the basis of standardised criteria by a questionnaire on personal habits, lifestyle, occupational or non-occupational exposure to Hg, medical history, number and area of dental amalgams. U-Hg was determined by hydride generation atomic absorption method (HG-AAS), with a detection limit of 0.5 microg/l and by flow injection (FI) inductively coupled plasma mass spectrometry (ICP-MS), with a detection limit of 0.03 microg/l. The median value of U-Hg, determined by HG-AAS, was 0.78 microg/g creatinine (0.75 for males and 0.83 for females), with 5 degrees and 95 degrees percentiles, respectively, of 0.17 and 3.66 microg/g creatinine. When determined by FI ICP-MS, the median value was 0.79 microg/g creatinine (0.77 for males and 0.79 for females) with 5 degrees and 95 degrees percentiles of, respectively, 0.12 and 5.02 microg/g creatinine. Among the independent variables, city of origin, area of dental amalgams, fish intake and tobacco smoking significantly influenced the U-Hg levels. The U-Hg reference values from this survey are lower than those from other recent investigations, probably due to characteristics and selection of the examined individuals and to the strict control of pre-analytical and analytical factors of variability.

Adult↗

Blood lead reference values: the results of an Italian polycentric study.

This paper presents the results of a polycentric study carried out in seven different areas, organized by the Italian Society of Reference Values (SIVR) for assessing reference values of lead in blood (B-Pb) at the current doses of the metal to general population. The estimated arithmetic mean for B-Pb in males was of 45.1 microg/l and 30.6 microg/l in females; the 95th centile was 100 and 60 for males and females, respectively. The main variables influencing B-Pb levels were gender, age, BMI, outside sport practice, alcohol consumption and smoking habits, while the geographic area and the urban residence did not affect the metal concentration in blood.

Adolescent↗

Determination of total urinary mercury by on-line sample microwave digestion followed by flow injection cold vapour inductively coupled plasma mass spectrometry or atomic absorption spectrometry.

The total mercury content in urine was determined by inductively coupled plasma mass spectrometry with the so-called cold vapour method after on-line oxidative treatment of the sample in a microwave oven (FI-MW-CV-ICPMS). Use of a KBr/KBrO(3) mixture, microwave digestion, and the final oxidation with KMnO(4), assure the complete recovery of the organic forms of Hg which would be difficult to determine otherwise if using only the CV-ICPMS apparatus. Quantitative recoveries were obtained for phenyl Hg chloride (PMC), dimethyl Hg (DMM), Hg acetate (MA) and methyl Hg chloride (MMC). Use of automatic flow injection microwave systems (FI-MW) for sample treatment reduces environmental contamination and allows detection limits suitable for the determination of reference values. Since no certified reference materials were commercially available in the concentration ranges of interest, the accuracy of the proposed procedure has been assessed by analysing a series of urine samples with two independent techniques, ICP-MS and AAS. When using the FI-MW-CV-ICP-MS technique, the detection limit was assessed at 0.03microg/L Hg, while with FI-MW-CV-AAS it was 0.2microg/L Hg. The precision of the method was less than 2-3% for FI-MW-CV-ICP-MS and about 3-5% for FI-MV-CV-AAS at concentrations below 1microg/L Hg. These results show that ICP-MS can be considered as a "reference technique" for the determination of total urinary Hg at very low concentrations, such as are present in non-exposed subjects.

Adult↗

Determination of 5-fluorouracil in environmental samples by solid-phase extraction and high-performance liquid chromatography with ultraviolet detection.

5-Fluorouracil (5-FU) is one of the most widely used antineoplastic drugs. It can be therefore considered to be a model compound for the identification of exposure routes during preparation and administration of cytostatic agents, especially for nucleoside analogue drugs. In this study, an HPLC-UV method was validated for determination of 5-FU in wipe samples by direct analysis of the aqueous solutions and in air samples by using solid-phase extraction (SPE). When samples were pre-treated on styrene-divinylbenzene resin SPE columns, a 20-fold preconcentration of the analyte was achieved. As regards air samples, correlation coefficients were always higher than 0.998 and the limit of detection was assessed at 15 ng on filter. In order to verify the reliability of these procedures, 5-chlorouracil was used as internal standard. The procedure presented here has been applied to the environmental monitoring of occupational exposed subjects. The amount of 5-FU ranged from 0.043 to 0.23 microg/m3 in air samples and from 0.2 to 470.1 microg/dm2 in wipe samples. 5-FU was also detected on the internal side of the gloves (0.07 to 3.77 microg/pair of gloves).

Chromatography, High Pressure Liquid↗

High-performance liquid chromatography/tandem mass spectrometry for the quantitative analysis of a novel taxane derivative (BAY59-8862) in biological samples and characterisation of its metabolic profile in rat bile samples.

A sensitive, specific, accurate and reproducible high-performance liquid chromatography (HPLC) analytical method was developed and validated for the quantification of the novel oral taxane analogue BAY59-8862 in mouse plasma and tissue samples. A fully automated solid-phase extraction procedure was applied to the plasma after internal standard (IS) addition, with only 0.2 mL volume of the sample loaded on a CN-Sep-pak cartridge. In the case of the tissues a very simple acetonitrile extraction was used to recover BAY59-8862 and its internal standard from liver. The procedure for the quantification of BAY59-8862 and its IS (IDN5127) is based on high-performance liquid chromatography/ion spray-tandem mass spectrometry, operating in selected ion monitoring mode. The retention times of BAY and IS were 7.21 and 10.36 min, respectively. In both plasma and tissue specimens the assay was linear in the range 50-5000 ng/mL (ng/g). The overall precision and accuracy were assessed on three different days. The results for plasma were within 6.1% (precision) and between 99 and 112% (accuracy), and for the liver samples within 7.3% and between 104 and 118%, respectively. The LOD was 5 ng/mL and 20 ng/g in the plasma and liver, respectively. In addition, the biliary excretion of the compound in rats was studied. The study showed that an oxidative chemical reaction was the preferred metabolic pathway for biliary excretion, and two sets of mono- and dihydroxylated metabolites were detected by LC/ISP-MS/MS experiments. With this method, BAY59-8862 pharmacokinetic was determined in mice. The combined results demonstrate that the methodology can be considered a valid approach to conduct pharmacokinetic and metabolic studies during preclinical and clinical investigations.

Animals↗

Effects of different schedules of oxaliplatin treatment on the peripheral nervous system of the rat.

The aim of this study was to determine the influence of oxaliplatin scheduling on the onset of peripheral neurotoxicity and ototoxicity in a rat model. Animals were treated with four different schedules of oxaliplatin using two cumulative doses (36 and 48 mg/kg intraperitoneally (i.p.)). The neuropathological examination evidenced dorsal root ganglia (DRG) nucleolar, nuclear and somatic size reduction with nucleolar segregation in the treated rats. Sensory nerve conduction velocity (SNCV) was reduced after oxaliplatin treatment, while the auditory pathway was unaffected. After treatment, platinum was detected in the kidney, DRG and sciatic nerve. After a 5-week follow-up period, recovery of the pathological changes in the DRG and sciatic nerves occurred, although platinum was still detectable in these tissues. The following conclusions may be drawn: the main targets of oxaliplatin neurotoxicity were the DRG; the shorter the interval between the injections, the higher the severity of peripheral neuropathy and this was also related to the cumulative oxaliplatin dose; the peripheral neurotoxicity tended to be reversible; ototoxicity was absent even with high cumulative doses of oxaliplatin.

Animals↗

Determination of methotrexate in human urine at trace levels by solid phase extraction and high-performance liquid chromatography/tandem mass spectrometry.

For biological monitoring of hospital personnel occupationally exposed to antineoplastic agents, highly sensitive and specific methods are required. In order to detect trace MTX urinary concentrations, a precise and accurate high-performance liquid chromatography/tandem mass spectrometry (HPLC-MS/MS) procedure, incorporating solid phase extraction, has been developed. Urine samples were purified by solid phase extraction (SPE) on octadecyl bonded, endcapped silica SPE columns. After eluting with methanol, the solvent was evaporated obtaining a 25-fold concentration of the analyte. This procedure was validated by using 7-OHMTX as internal standard. Calibration curves had correlation coefficients always higher than 0.999, and the limit of detection was assessed at 0.2 microg L(-1). High specificity of the HPLC-MS/MS technique assures that no interfering substances are detected rather than the analyte of interest.

Antimetabolites, Antineoplastic↗

Determination of methotrexate in environmental samples by solid phase extraction and high performance liquid chromatography: ultraviolet or tandem mass spectrometry detection?

In order to assess exposure levels of hospital personnel involved in the preparation and administration of antineoplastic drugs, environmental monitoring should be carried out. Wipe samples, pads, gloves and air samples should be collected at the end of each work shift, properly treated and then analysed using instrumental techniques which are sufficiently sensitive and specific to detect even trace amounts of drug. In this study, a method using high performance liquid chromatography/tandem mass spectrometry (HPLC/MS/MS), incorporating solid phase extraction (SPE), was validated for determination of methotrexate (MTX) in wipe and air samples. Each step of the method was first developed and optimised using ultraviolet detection (UV), and afterwards tandem mass spectrometry was used to obtain a lower limit of quantitation when the expected drug level was less than the analytical UV detection limit. SPE enabled a 20-fold preconcentration of the analyte when using HPLC/UV and a further 30-fold preconcentration was obtained when analysing samples by HPLC/MS/MS. For example, the limit of quantitation (LLQ) was lowered from 3000 ng on wipe (direct injection onto an HPLC/UV system) to 5 ng on wipe (SPE plus HPLC/MS/MS). 7-hydroxymethotrexate was used as internal standard to assess precision and accuracy.

Antimetabolites, Antineoplastic↗

Rapid and sensitive determination of paclitaxel (Taxol(R)) in environmental samples by high-performance liquid chromatography tandem mass spectrometry

A new, rapid and sensitive method for the quantitative determination of paclitaxel (Taxol(R)) in environmental samples is developed and validated. This highly sensitive and specific method was successfully applied to an environmental monitoring study for identifying occupational exposure situations to anticancer drugs. After addition of an internal standard, 2'-methylpaclitaxel, aqueous extraction of wipe samples or air filters followed by a single-step liquid-liquid extraction with ethyl acetate was performed. Extraction efficiency averaged 90%. The method is based on analysis by liquid chromatography with tandem mass spectrometry in selected reaction monitoring mode of environmental samples from the preparation and administration of cytostatic agents. The assay is linear (r = 0.998) in the range 2-64 ng on filters (air samples), and 20-320 ng on wipe samples. The accuracy of the assay is always </=20% for both matrices, and the intra- and interday assay variability of paclitaxel ranged from 7 to 19% and 10 to 14%, respectively. The lower limit of quantification is assessed at 2 ng on filter and 10 ng on wipe samples. Copyright 2000 John Wiley & Sons, Ltd.

Journal Article↗

Clinical and pharmacological phase I study with accelerated titration design of a daily times five schedule of BBR3464, a novel cationic triplatinum complex.

OBJECTIVES: To define the maximum tolerated dose (MTD), the toxicity and pharmacokinetic profile of BBR3464, a novel triplatinum complex. PATIENTS AND METHODS: Fourteen patients with advanced solid tumors not responsive to previous antitumor treatments received BBR 3464 on a daily x 5 schedule every twenty-eighth day. The drug was given as a one-hour infusion with pre-and post-treatment hydration (500 ml in one hour) and no antiemetic prophylaxis. The starting dose was 0.03 mg/m2/day. A modified accelerated titration escalation design was used. Total and free platinum (Pt) concentrations in plasma and urine were assessed by ICP-MS on days 1 and 5 of the first cycle. RESULTS: Dose was escalated four times up to 0.17 mg/m2/day. Short-lasting neutropenia and diarrhea of late onset were dose-limiting and defined the MTD at 0.12 mg/m2. Nausea and vomiting were rare, neither neuro- nor renal toxic effects were observed. BBR3464 showed a rapid distribution phase of 1 hour and a terminal half-life of several days. At 0.17 mg/m2 plasma Cmax and AUC on day 5 were higher than on day 1, indicating drug accumulation. Approximately 10% of the equivalent dose of BBR3464 (2.2%-13.4%) was recovered in a 24-hour urine collection. CONCLUSIONS: The higher than expected incidence of neutropenia and GI toxicity might be related to the prolonged half-life and accumulation of total and free Pt after daily administrations. Lack of nephrotoxicity and the low urinary excretion support the use of the drug without hydration. The single intermittent schedule has been selected for clinical development.

Adolescent↗

Levels of house-dust-mite allergen in homes of nonallergic people in Pavia, Italy.

BACKGROUND: HDM distribution varies between geographic areas and may be affected by housing characteristics. We quantified Der p 1 and Der f 1 and assessed the relationships between their levels and housing characteristics in homes of nonallergic subjects. METHODS: Der f 1 and Der p 1 were measured by ELISA in dust samples from living-room floors and mattresses of 44 homes of nonallergic subjects in Pavia. Information about household characteristics was obtained by questionnaire. RESULTS: Der p 1 and Der f 1 concentrations (microg/g dust, median) were 0.34 and 7.8 on mattresses, and 0.15 and 0.83 on living-room floors. Higher Der f 1 levels on mattresses were associated with synthetic pillows (P<0.05), and (only when expressed as microg/m2) with bedding washing temperature of < or = 60 degrees C (P<0.05). Der f 1 levels were higher on the living-room floors of homes located on lower (< or =first) floors (P<0.05). Good correlations were found between Der p 1 and Der f 1 expressed as microg/g dust and microg/m2 on both mattresses and living-room floors. CONCLUSIONS: In homes of nonallergic subjects in northern Italy, Der f 1 exceeded the threshold for sensitization in a high proportion of mattress samples.

Animals↗

Distribution of paclitaxel within the nervous system of the rat after repeated intravenous administration.

The distribution of paclitaxel (Taxol) within the central and peripheral nervous system after repeated administration of this antineoplastic agent is still largely unknown. In this study we determined for the first time paclitaxel tissue concentration in the brain, spinal cord, dorsal root ganglia (DRG) and sciatic nerve using an experimental paradigm in the rat which reproduces the features of paclitaxel peripheral neurotoxicity in humans. Pathological confirmation of the onset of paclitaxel-induced peripheral neurotoxicity was performed. In order to achieve reliable results even with low concentrations of paclitaxel, a newly reported analytical method (high-performance liquid chromatography with tandem mass spectrometry) was used. We demonstrated that paclitaxel has easy access to the DRG, where it accumulates, while the lowest concentrations of the drug were measured in the brain. The intermediate concentrations of paclitaxel observed in the sciatic nerve and spinal cord may be due to paclitaxel transport along the centrifugal and centripetal branches of the DRG neuron axons.

Animals↗

Chronic exposure to aluminium impairs the glutamate-nitric oxide-cyclic GMP pathway in the rat in vivo.

Aluminium is neurotoxic and is considered a possible etiologic factor in Alzheimer's disease, dialysis syndrome and other neurological disorders. The molecular mechanism of aluminium-induced impairment of neurological functions remains unclear. We showed that aluminium impairs the glutamate-nitric oxide-cGMP pathway in cultured neurons. The aim of this work was to assess by in vivo brain microdialysis whether chronic administration of aluminium in the drinking water (2.5% aluminium sulfate) also impairs the glutamate-nitric oxide-cGMP pathway in the cerebellum of rats in vivo. Chronic exposure to aluminium reduced NMDA-induced increase of extracellular cGMP by ca 50%. The increase in extracellular cGMP induced by the nitric oxide generating agent S-nitroso-N-acetylpenicillamine was higher (240%) in rats treated with aluminium than in controls. Immunoblotting experiments showed that aluminium reduced the cerebellar content of calmodulin and nitric oxide synthase by 34 and 15%, respectively. Basal activity of soluble guanylate cyclase was decreased by 66% in aluminium-treated rats, while the activity after stimulation with S-nitroso-N-acetylpenicillamine was similar to controls. Basal cGMP in the cerebellar extracellular space was decreased by 50% in aluminium-treated rats. These results indicate that chronic exposure to aluminium reduces the basal activity of guanylate cyclase and impairs the glutamate-nitric oxide-cGMP pathway in the animal in vivo.

Aluminum↗

Seasonal effect on airborne pyrene, urinary 1-hydroxypyrene, and benzo(a)pyrene diol epoxide-hemoglobin adducts in the general population.

Exposure to airborne polycyclic aromatic hydrocarbons (PAHs) in 65 employees (40 sampled both in summer and winter, 15 sampled in summer only, and 10 sampled in winter only) with no occupational exposure to PAHs was assessed by measuring: personal exposure to pyrene, urinary excretion of 1-hydroxypyrene (1-OHP), and benzo(a)pyrene diol epoxide adducts to hemoglobin (BPDE-Hb). Overall, office employees were exposed to significantly higher levels of pyrene in winter (4.54 +/- 2.35 ng/m3, mean +/- SD) than in summer (1.67 +/- 1.92 ng/m3, mean +/- SD; P < 0.001), but no such seasonal variability was observed in 1-OHP excretion. Tobacco smoking was the major determinant of 1-OHP excretion. BPDE-Hb adducts were measured by gas chromatography-mass spectrometry as benzo(a)pyrene tetrols (BPT) released from adducted hemoglobin. In the 65 employees analyzed, mean BPT levels +/- SD were higher in winter (0.14 +/- 0.38 fmol/mg Hb) than summer (0.031 +/- 0.022 fmol/mg Hb). This difference was not statistically significant, probably because of the small proportion of subjects with detectable adducts (11% in summer and 16% in winter). BPDE-Hb adducts were not significantly associated with sex, age, diet, smoking habits, or with pyrene levels and 1-OHP excretion. This is the first report providing reference BPDE-Hb adduct values for the general population not occupationally exposed to environmental PAHs and shows a tendency to seasonal variability, with higher BPT levels in winter when environmental PAHs are also high.

Adolescent↗

Quality control of 99Mo/99Tcm generators: results of a survey of the Radiopharmacy Working Group of the Italian Association of Nuclear Medicine (AIMN).

A multicentre survey of the quality control of 99Tcm generators has been completed: 245 generators from seven different commercial sources were tested over a period of 2 years. The results indicate that the mean pH of the eluates was 5.8 +/- 0.6; the aluminium contents were typically < 10 ppm; the radiochemical purity was 99.8 +/- 0.4% and the median 99Mo content was 3.8 x 10(-4) percent. The elution profiles gave a volume of 1.9 ml to obtain 50% of the total eluted activity and of 4.9 ml to obtain 95%. Other radionuclide impurities and heavy metal breakthrough were evaluated by graphite furnace absorption spectrometry and inductively coupled plasma mass spectrometry. National guidelines for the standardization of radiopharmacy procedures are currently being compiled.

Hydrogen-Ion Concentration↗

Significance and utility of reference values in occupational medicine.

Although it is generally accepted that reference values can be included among the instruments of modern occupational medicine, problems arise when applying them from clinical chemistry to the needs of occupational medicine. Here some general aspects regarding reference values beginning from their theoretical basis, their significance and importance and their possible use in occupational medicine are reviewed. Furthermore, their relationship with other more familiar 'guideline values', such as action levels and limit values, is demonstrated.

Guidelines as Topic↗

High-performance liquid chromatography tandem mass spectrometry procedure with automated solid phase extraction sample preparation for the quantitative determination of paclitaxel (Taxol) in human plasma.

A sensitive, specific, accurate and reproducible analytical method was developed and validated for the quantitation of the anticancer agent paclitaxel in human plasma. This procedure is based on high performance liquid chromatography/ion spray-tandem mass spectrometry. This methodology is highly specific because a MS/MS technique (multiple reactant-ion monitoring, MRM) was used for both paclitaxel and its internal standard. The use of a fully automated solid phase extraction procedure, using a CN Sep-pak cartridge, to improve the detection limit and quantification limit of paclitaxel in human plasma samples, was evaluated. The method involves the addition of methyl-paclitaxel as internal standard (i.s.). The retention times of paclitaxel and the I.S. were 2.8 and 4.0 min., respectively. The assay was linear over the range 5 to 500 ng/mL, with a quantification limit of 5 ng/mL having a coefficient of variation (c.v.) < 10%. Standard calibration curves, performed on three different days, had correlation coefficients always greater than 0.998. The intra and inter-day precision were within 12%, and accuracy was included in the range 102-110%. Paclitaxel recovery assessed at 15,250 and 500 ng/mL, was determined to be greater than 85%. The assay is applicable to clinical pharmacokinetic studies.

Antineoplastic Agents, Phytogenic↗