A case report: Use of FT-IR analysis to improve Colovesical fistula diagnosis.

Colovesical fistula (CVF) is an abnormal connection between the colon and the urinary bladder. Faecaluria, reported in 40-70% of cases, is virtually pathognomonic for CVF. During the 5th day of recovery in an 84 years old subject, the passage of cloudy, malodorous urine with visible debris was observed. According to the pathognomonic character of faecaluria, the sample was signed to the laboratory for biochemical and microbiological investigation, able to define the type and origin of materials. Following clinical requirements, both biochemical pathways and instrumental procedures able to confirm or exclude the presence of faecal components in urine were considered. No biochemical compound or component addressing faecal compounds in urine results available between laboratory tests. The brown powder component of the pellet was identified as Keratin, with 90% overlapping with the reference spectrum of the compound. FT-IR analysis on urine pellet can be proposed as a simple, non-invasive, and fast method to improve the diagnostic course of CVF.

Fully automated solid-phase microextraction-fast gas chromatography-mass spectrometry method using a new ionic liquid column for high-throughput analysis of sarcosine and N-ethylglycine in human urine and urinary sediments.

A fully automated, non invasive, rapid and high-throughput method for the direct determination of sarcosine and N-ethylglycine in urine and urinary sediments using hexyl chloroformate derivatization followed by direct immersion solid-phase micro extraction and fast gas chromatography-mass spectrometric analysis was developed and validated. The use of a new ionic liquid narrow bore column, as well as the automation and miniaturization of the preparation procedure by a customized configuration of the utilized XYZ robotic system, allowed a friendly use of the GC apparatus achieving a quantitation limit of 0.06 µg L(-1) for sarcosine, good repeatability with CV always lower than 7% and reduced analysis times useful for point-of-care testing. The method was then applied for the analysis of 56 samples of urine and urinary sediments in healthy subjects, in those with benign prostatic hypertrophy and in patients with clinically localized prostate cancer. The results obtained showed that the medians of sarcosine/creatinine in urine were 103, 137 and 267 µg g(-1) respectively, thus assessing the potential use of sarcosine as urinary biomarker for prostate cancer detection. The highest values of sensitivity (79%) and specificity (87%) were obtained in correspondence of a cut-off value of 179 µg sarcosine(g creatinine)(-1), thus by using this cut-off threshold, sarcosine was significantly associated with the presence of cancer (p<0.0001). Finally, ROC analyses proved that the discrimination between clinically localized prostate cancer and patients without evidence of tumor is significantly correlated with sarcosine.

Novel method for simultaneous aqueous in situ derivatization of THC and THC-COOH in human urine samples: validation and application to real samples.

The present work describes the validation of a novel aqueous in situ derivatization procedure with trimethyloxonium tetrafluoroborate (TMO) as methylating agent for the simultaneous, quantitative analysis of Δ(9)-tetrahydrocannabinol (THC) and 11-nor-Δ(9)-tetrahydrocannabinol carboxylic acid (THC-COOH) in human urine. The derivatizing agent is directly added to the urine sample and the methyl-derivatives are then recovered by liquid-liquid extraction procedure. Gas chromatography-mass spectrometry was used to detect the derivatives in selected ion monitoring mode. The limits of detection were 0.7 ng/mL for THC and 0.5 ng/mL for THC-COOH, whereas the limits of quantification were 1.9 and 0.9 ng/mL, respectively. The method has been applied to 60 real samples both positive and negative to immunochemical screening test resulting to be very useful and reliable in routine analysis of THC-COOH in human urine for toxicological and forensic purposes.

Locating industrial VOC sources with aircraft observations.

Observation and characterization of environmental pollution, focussing on Volatile Organic Compounds (VOCs), in a high-risk industrial area, are particularly important in order to provide indications on a safe level of exposure, indicate eventual priorities and advise on policy interventions. The aim of this study is to use the Solid Phase Micro Extraction (SPME) method to measure VOCs, directly coupled with atmospheric measurements taken on a small aircraft environmental platform, to evaluate and locate the presence of VOC emission sources in the Marghera industrial area. Lab analysis of collected SPME fibres and subsequent analysis of mass spectrum and chromatograms in Scan Mode allowed the detection of a wide range of VOCs. The combination of this information during the monitoring campaign allowed a model (Gaussian Plume) to be implemented that estimates the localization of emission sources on the ground.

Compound A, formaldehyde and methanol concentrations during low-flow sevoflurane anaesthesia: comparison of three carbon dioxide absorbers.

AIM: To determine compound A, formaldehyde and methanol concentrations in low-flow anaesthesia using different carbon dioxide absorbers. METHODS: Fifteen patients scheduled for general or urological surgery were exposed to low-flow (500 ml/min) anaesthesia with sevoflurane. The patients were randomly allocated to three groups: soda lime, DrägerSorb Free or Amsorb Plus. The concentrations of compound A, formaldehyde and methanol were sampled and analysed from the limbs of the anaesthesia circuit at T30 (30 min after the start of low-flow sevoflurane anaesthesia), T90 (90 min) and T150 (150 min). The temperatures of the absorbers were measured at the same time. RESULTS: Statistically significant differences (P < 0.05) were found in the production of compound A from soda lime (with the highest values), DrägerSorb Free and Amsorb Plus at each measurement time. Only traces of methanol (ranging from < 0.131 to 3.799 mg/m(3)) were measured, higher with Amsorb Plus (statistically significant differences were found only at T90). The formaldehyde values (ranging from < 0.1227 to 17.79 mcg/m(3) p.p.b.) were higher with soda lime, and the difference was statistically significant at T150 and, in the inspiratory limb only, at T90. The temperatures of the absorbers were higher for soda lime and lower for Amsorb Plus; the difference was statistically significant at T0 in the upper canister and at T30 in both canisters. CONCLUSION: The concentrations of harmful products in the circuit were negligible and were lower using the new-generation absorbers. Using Amsorb Plus, the temperatures in the canisters were lower than with the other two absorbers.

Evaluation of occupational exposure to high-level disinfectants in endoscopic services in an Italian hospital.

The aim of this study is the evaluation of exposure to airborne, high-level disinfectants to efficiently organize prevention of the risks due to the manipulation of these substances in the endoscopic units in medical facilities. In field and personal samples in the breathing zone of the workers were taken in 27 endoscopic units in a hospital during the replacement of high-level disinfectants in basins, tubes and lavaendoscopes. After a campaign of environmental monitoring of glutaraldehyde in nineteen endoscopic units (176 employees) of the hospital and considering the entity of glutaraldehyde problem, two substitutes, peracetic acid and electrolyzed acid water, have recently been introduced. The level of glutaraldehyde was higher than the TLV-Ceiling in 13 out of 19 working units, while the value of peracetic acid resulted higher than TLV-TWA in 1 out of 15. EAW has recently been used in two units and the chlorine environmental concentrations resulted lower than the sensibility limit of the method (<75 microg/m3). The results obtained during this study of measurements allowed to identify those operations which have the highest degree of risk for employees; this serves for taking suitable measures for prevention and individual protection as well as for evaluating current practices and decisional processes in the hospital.

Determination of S-phenylmercapturic acid by GC-MS and ELISA: a comparison of the two methods.

S-phenylmercapturic acid (PMA) is a specific urinary biomarker of benzene at exposure levels lower than 1 ppm. However, measuring PMA in urine is an expensive task by either GC or HPLC due to the necessity of extensive sample pretreatment. In the present study, a commercial chemiluminescence enzyme-linked immunosorbent assay (ELISA) test for PMA and GC-MS were used for screening urine samples of 60 workers employed in petrochemical settings. The ELISA results were evaluated by comparison with the GC-MS. Overall, the ELISA test proved sensitive (limit of detection=0.1 microg l(-1)), rapid, robust and reliable, affording results in good agreement with the GC-MS (54% of measurements) and no false-negatives. On the other hand, 46% of the ELISA assays were assigned as false-positives (arbitrarily established when ELISA >5 microg l(-1), GC-MS <5 microg l(-1) and a correlation coefficient of 0.687 was calculated between the two methods. It appears that urinary PMA routine biomonitoring on large numbers of samples is carried out in a cost-effective and rapid approach by preliminary screening with the ELISA assay followed by GC-MS confirmation of concentrations exceeding the biological exposure index for PMA.

Sevoflurane low-flow anaesthesia: best strategy to reduce Compound A concentration.

BACKGROUND: To define the best strategy to reduce Compound A production in Sevoflurane low-flow anaesthesia by experiments in vitro and in vivo of different absorbers and different anaesthesia machines. METHODS: In vitro Compound A has been measured at 45 degrees C in vitro following Sevoflurane interactions with potassium hydroxide, sodium hydroxide, soda lime, Dragersorb 800 Plus and Amsorb, a new absorber that does not contain sodium or potassium hydroxide. In vivo Compound A concentration in the anaesthesia circuit (inspiratory branch) has been measured using an indirect sampling method through absorber vials (SKC) with active coal granules, during low flows (500 ml/min) general anaesthesia using soda lime, Dragersorb 800 Plus or Amsorb as absorber. Compound A was also measured during low flows (500 ml/min) general anaesthesia using as carbon dioxide absorber soda lime with different anaesthesia machines. RESULTS: In vitro at 45 degrees C Compound A concentration with soda lime and Dragersorb 800 Plus was about 10 times higher than with Amsorb. In vivo the Compound A concentrations in the inspiratory branch of the circuit were lower in the group with Amsorb. CONCLUSION: The Compound A production is minimal with Amsorb as carbon dioxide absorber.