Perilymphatic fistulas of the inner ear constitute abnormal leaks of perilymphatic fluid into the middle ear or mastoid air cell system and represent a rare cause of otorrhea. We report the case of a 5-month-old child presenting with sudden otorrhea. High resolution CT cisternography showed a malformation of the middle ear and a passage of contrast-enhanced CSF into the tympanic cavity through the left oval window. Surgery confirmed a tear of the tympanic membrane as well as a stapes malformation with aplasia of the crura and an associated perilymphatic fistula through a defect in the stapes footplate. The fistula was closed with adipose tissue from the ear lobe.

Cerebrospinal Fluid Otorrhea↗

PubMedDate not supplied

[Biological monitoring of occupational exposure to sevoflurane].

Sevoflurane has been used in the last few years in brief surgical operations, either alone or in combination with nitrous oxide. Occupationally exposed groups include anesthesiologists, surgeons and operating room nurses. In 1977 the National Institute for Occupational Safety and Health (NIOSH) recommended that occupational exposure to halogenated anesthetic agents (halothane, enflurane, and isoflurane), when used as the sole anesthetic, should be controlled so that no worker would be exposed to time-weighted average concentrations greater than 2 ppm during anesthetic administration. When halogenated anesthetics are associated with nitrous oxide, NIOSH recommends that the limit value should not exceed 0.5 ppm. We think these recommendations can be extended to sevoflurane. Metabolism of sevoflurane is catalyzed by cytochrome P-450; this involves oxidation of the fluoromethyl side chain of the molecule, followed by glucuronidation. Two urinary metabolites of sevoflurane have been identified: inorganic fluoride (which, however, is not specific) and a non-volatile compound that yields hexafluoroisopropanol (HFIP) when digested with the enzyme beta-glucuronidase. In order to investigate the role of urinary HFIP as an indicator of occupational exposure to sevoflurane (CI, ppm), CI was measured in 145 members of 18 operating room staffs. The measurements of the time-weighted average of CI in the breathing zone were made by means of diffusive personal samplers. Each sampler was exposed during the whole working period. Sevoflurane was desorbed with CS2 from charcoal and the concentrations were measured on a gas chromatograph (GC) equipped with a mass selective detector (MSD). The GC was equipped with a 25 meter cross-linked phenylmethylsilicon column (internal diameter 0.2 mm). GC conditions were as follows: injector column temperature = 200 degrees C; column temperature = 30 degrees C; carrier gas = helium; injection technique of samples = splitless. The analytical conditions for the MSD were the following: ion mass monitored = 131 m/e; dwell time = 50 msec; selected ion monitoring window time = 0.1 amu; electromultiplier = 400 V. Urine samples were collected near the end of the shift and were analyzed for HFIP by head-space gas chromatography after glucuronide hydrolysis. 0.5 ml of urine and 1.5 ml of 10 M sulfuric acid were added to 21.8 ml headspace vials. The vials were immediately capped, vortexed, and loaded into the headspace autosampler. Samples were maintained at 100 degrees C for 30 min, after which glucuronide hydrolysis was 99% complete. Analyses were performed on a GC equipped with a MSD. The analytical conditions for urine analysis were as follows: cross-linked 5% phenylmethylsilicon column (internal diameter 0.2 mm, length 25 m); column temperature = 35 degrees C; carrier gas = helium. The analytical conditions for the MSD were: monitored ions = 51.05 and 99; dwell time = 100 ms; selected ion monitoring window time = 0.1 amu; electromultiplier voltage = 2000 Volt. With our analytical procedure, the detection limit of HFIP in urine was 20 micrograms/L. The variation coefficient (CV) for HFIP measurement in urine was 8.7% (on 10 determinations; mean value = 1000 micrograms/L). The median value of CI was 0.77 ppm (Geometric Standard Deviation = 4.08; range = 0.05-27.9 ppm). The correlation between CI and HFIP (Cu, microgram/L) was: Log Cu (microgram/L) = 0.813 x Log CI (ppm) + 2.517 (r = 0.79, n = 145, p < 0.0001). On the basis of the equation it was possible to establish tentatively the biological limit values corresponding to the respective occupational exposure limit values proposed for sevoflurane. According to our experimental results, HFIP values of 488 micrograms/L and 160 micrograms/L correspond to airborne sevoflurane concentrations of 2 and 0.5 ppm respectively.

Anesthesiology↗

PubMedDate not supplied

[High-pressure liquid chromatography (HPLC) with UV developer for the analysis of N-acetyl-S-(N-methylcarbomoyl)cysteine (AMCC)].

N,N-dimethylformamide (DMF) is a solvent widely used to prepare synthetic fibers. Biomonitoring of DMF is usually performed by measuring urinary N-methylformamide, which allows us to estimate exposure during the working day. An alternative biomarker is the mercapturic acid N-acetyl-S-(N-methylcarbamoyl)cysteine (AMCC) whose excretion accounts for about 13% of the absorbed DMF dose. Owing to its slow excretion (mean half-life = 23 hours) the urinary levels of AMCC at the end of a workweek reflect the cumulative dose of DMF during the whole week. Methods given in literature for measuring AMCC need the derivatization of the molecule before analysis. The paper describes a method for the determination of urinary AMCC by high-performance liquid chromatography (HPLC) with direct UV detection. Samples were purified by solid phase extraction with C18 and ENV+ cartridges, then 10 microliters were directly injected onto an Aminex HPX-87H Ion Exclusion column maintained at a temperature of 37 degrees C. Analyses were performed by isocratic run with 1 mM sulphuric acid delivered at 0.85 mL/min. The detector was set at 196 nm. Under these conditions, AMCC eluted at 11.1 min., and the detection and quantification limits were 1.32 mg/L and 3.96 mg/L, respectively. The performance of the method was evaluated on samples containing 25 mg/L and 400 mg/L of AMCC: each sample was analysed three times. The mean recovery of the extraction procedure was 88.3%. The precision (CV%) and the accuracy (Error%) ranged from 0.8% to 2.9%, and from -1.2% to +3.2%. The calibration curve was linear up to a concentration of 1000 mg/L, the coefficient of correlation was r = 0.9997. AMCC was measured in urine samples from 30 exposed and 20 unexposed (smokers and nonsmokers) subjects. Measurable amounts of AMCC were found in all of the samples from workers exposed to DMF; on the contrary, none of the samples from unexposed subjects contained this metabolite. The proposed method is sufficiently sensitive and specific for the evaluation of occupational exposure to DMF, thus it could be useful for the biological monitoring of workers exposed to this solvent.

Acetylcysteine↗

PubMedDate not supplied

Treatment options in patients with recurrent ovarian cancer.

The majority of patients with advanced ovarian cancer need a second-line treatment for recurrent disease after surgical cytoreduction and first-line chemotherapy. In these patients, treatment planning is mainly dependent on the platinum-free-interval. The patients may be distinguished as platinum-refractory (progression under platinum-based therapy), platinum-resistant (relapse within 6 months), or platinum-sensitive (relapse after 6 months). Patients with platinum-refractory or -resistant disease should be encouraged to enter clinical trials. Alternatively, these patients could receive tamoxifen or a non-platinum single-agent therapy. Since response rate and duration to different single-agents are similar, patient convenience, toxicities from prior treatment, side-effects and costs play a role in the drug selection for salvage chemotherapy. Patients with platinum-sensitive disease should receive carboplatin based or carboplatin-plus paclitaxel-based regimens. Secondary surgical cytoreduction may have a role in highly selected patients with good performance status, with long disease-free interval and without extra-abdominal or liver metastases.

Female↗

PubMedDate not supplied

[Monitoring air dispersed concentrations of aldehydes during the use of ortho-phthalaldehyde and glutaraldehyde for high disinfection of endoscopes].

Solutions of glutaraldehyde (GTA) and ortho-phthalaldehyde (OPA) can both be used for low-temperature disinfection of endoscopes. Currently, GTA is being replaced by OPA (an aromatic dialdehyde) at the San Matteo Hospital, as OPA is less dangerous for health care workers than GTA, but has a similar capacity to kill viruses, bacteria and spores. The aim of the study was to compare air levels of GTA and OPA in several endoscopy units at our hospital. The air samples were analysed by means of both Infrared Spectroscopy (IR) and HPLC-UV (High Performance Liquid Chromatography with UV detection). The HPLC method gave a much lower aldehyde value when using OPA (8.4 micrograms/m3) compared to that obtained when GTA was used to disinfect endoscopes (21.279.3 micrograms/m3). Both HPLC and IR methods detected low levels of OPA in air, the mean values being below 10 micrograms/m3. In addition, we studied the resistance of various types of gloves to OPA. Tests showed that OPA permeated vinyl gloves more rapidly (26,628 ng/cm2 per hour) than nitrile gloves (13.9 ng/cm2 per hour).

Air Pollution, Indoor↗

PubMedDate not supplied

[Biological monitoring of occupational exposure to desflurane].

In these last years Desflurane (D) has become used, alone or in combination with nitrous oxide, in surgical procedures. Occupational exposed groups include anesthesiologists, other physicians, (e.g. surgeons) and operating room nurses. Desflurane is a halogenated methylethylether which is administered by inhalation. Desflurane is halogenated exclusively with fluorine. The blood/gas partition coefficient of Desflurane is 0.42. Changes in the clinical effects of Desflurane rapidly follow changes in the inspired concentration. Studies in man indicate that Desflurane washes into the body rapidly. It also washes out of the body rapidly, allowing flexibility in adjustment of the depth of anaesthesia. Desflurane is eliminated via the lungs, undergoing only minimal metabolism (0.02%). In order to investigate the role of urinary D as an indicator of occupational exposure to Desflurane (CI, ppm), CI was measured in 21 members of operating room staffs. For the measurement of environmental concentration of Desflurane (CI), the ambient air was sampled using personal passive dosimeters. The analyte was desorbed by a water-methanol mixture and was analysed by means a gas chromatograph--mass spectrometer (GC-MSD) and headspace technique. The biological monitoring of exposed workers was conducted by determining the concentration of Desflurane in urine (Cu, microgram/L). Urine concentrations of Desflurane were determined by headspace analysis using GC-MSD. Significant correlations were found between the environmental Desflurane concentration and the urinary concentrations. The correlation between CI (ppm) and Cu (microgram/L) was: Log D (Cu, microgram/L) = .191 + .922 * LogCI; r = .916 On the basis of the equation it was possible to establish tentatively the biological limit values corresponding to the respective occupational exposure limit values proposed for Desflurane.

Air Pollutants, Occupational↗

PubMedDate not supplied

[Measurement of breast cancer dimensions: correlation between mammographic and macroscopic data].

In this study the maximum diameters of 48 mammary carcinomas of various istotype detected preoperatively on mammography are compared with the diameters of neoplasms diagnosed by the anatomo pathologist on macroscopic examination of the excised part. Statistical analysis has shown that for every mammographic value it is possible to infer the corresponding real macroscopic value by adding or subtracting 0.45 cm.

Breast Neoplasms↗

PubMedDate not supplied

[Excretion kinetics of phenylhydroxyethyl mercapturic acids (PHEMAs), ethanol consumption, and chronic exposure to styrene: preliminary data on humans].

Styrene (S) is a widely used aromatic hydrocarbon, responsible for several adverse effects. In humans, the metabolism of S is well characterized: besides the major metabolites (mandelic and phenylglyoxylic acid), a minor metabolic pathway leads to phenylhydroxyethyl mercapturic acids (PHEMAs) [N-acetyl-S-(1-phenyl-2-hydroxyethyl)-L-cysteine (M1) and N-acetyl-S-(2-phenyl-2-hydroxyethyl)-L-cysteine (M2)], that are potentially useful for biomonitoring purposes. A pilot study on a volunteer exposed under controlled conditions to S, with or without ethanol administration, allowed us to characterize the excretion profile of PHEMAs and the ethanol-induced interference on PHEMAs metabolic pathway. We further considered a group of 9 workers exposed to S during the working week to determine the confounding role of chronic exposure. Our results confirm the wide interindividual variability of both the biotransformation rate of S into PHEMAs and of the excretion rate of these metabolites. Moreover, both the above parameters changed during the working week, suggesting the existence of a large intraindividual variability as a consequence of the exposure to S and to other solvents. As a practical rule, the data indicate that it is necessary to collect samples at the beginning of the working week when studies on the correlation between genotype and phenotype are carried out. Finally, the results emphasise the importance of excluding an even extemporary ethanol assumption when practicing a biological monitoring programme based on the determination of urinary PHEMAs.

Acetylcysteine↗