Simultaneous determination of methanol, acetaldehyde, acetone, and ethanol in human blood by gas chromatography with flame ionization detection.

BACKGROUND: Methanol, acetaldehyde, acetone, and ethanol, which are commonly used as biomarkers of several diseases, in acute intoxications, and forensic settings, can be detected and quantified in biological fluids. Gas chromatography (GC)-mass spectrometry techniques are complex, require highly trained personnel and expensive materials. Gas chromatographic determinations of ethanol, methanol, and acetone have been reported in one study with suboptimal accuracy. Our objective was to improve the assessment of these compounds in human blood using GC with flame ionization detection. METHODS: An amount of 50 µl of blood was diluted with 300 µl of sterile water, 40 µl of 10% sodium tungstate, and 20 µl of 1% sulphuric acid. After centrifugation, 1 µl of the supernatant was injected into the gas chromatograph. We used a dimethylpolysiloxane capillary column of 30 m × 0.25 mm × 0.25 µm. RESULTS: We observed linear correlations from 7.5 to 240 mg/l for methanol, acetaldehyde, and acetone and from 75 to 2400 mg/l for ethanol. Precision at concentrations 15, 60, and 120 mg/l for methanol, acetaldehyde, and acetone and 150, 600, and 1200 mg/ml for ethanol were 0.8-6.9%. Ranges of accuracy were 94.7-98.9% for methanol, 91.2-97.4% for acetaldehyde, 96.1-98.7% for acetone, and 105.5-111.6% for ethanol. Limits of detection were 0.80 mg/l for methanol, 0.61 mg/l for acetaldehyde, 0.58 mg/l for acetone, and 0.53 mg/l for ethanol. CONCLUSION: This method is suitable for routine clinical and forensic practices.

[Drug interactions in an elderly population. Prospective assessment of their frequency and seriousness among 56 patients]. / Interactions médicamenteuses dans une population âgée.

OBJECTIVE: To assess the nature and the number of potential adverse drug interactions by analysis of outpatient prescriptions for elderly patients, of medications taken during the week before hospitalization in a general surgery department. METHOD: The study of 56 patients older than 65 years was conducted from November 2002 through February 2003. The outpatient prescriptions corresponding to medications taken during the 7 days before admission were analyzed by a pharmacy resident, who used data-processing tools and databases. RESULTS: Most patients (83%) knew the reason for their prescription. Thirteen (28%) reported using over-the-counter medication. Only 89% of the patients reported complete compliance with the prescription. The average age of the patients was 72.1 +/- 6.3 years and the median was 71 years [65-91]; 43% were women and 57% men. The 257 lines of prescriptions analyzed averaged 5.7 +/- 2.6 drugs (range: 2-10) per prescription. The average number of possible interactions was 3.1 +/- 2.8 per prescription for a total of 89 listed potential interactions. The levels observed were 3 warnings (3%), 37 precautions (42%) and 49 possible adverse interactions (55%). No contraindication was noted. The drugs mentioned most often were benzodiazepines, diuretics, conversion enzyme inhibitors, angiotensin II inhibitors, and beta-blockers. The potential risks most often found were hypotension, depression of the central nervous system, hypoglycemia and acute renal failure. The drug interactions were mainly due to the accumulation of the effects of separate drug classes. Deterioration in renal function was often noted as plasma concentration of the second drug increased. DISCUSSION: This exploratory study shows the reality of the iatrogenic risk for elderly patients. This analysis of outpatient prescriptions is consistent with findings in the literature. Analysis of interactions is conducted on a pairwise basis. It is thus difficult to envisage the consequences of the association of 5 or more drugs in patients with complex illnesses and diminished physiological and metabolic capacity. Patient files kept by the pharmacist could provide information about individual combinations ofthe prescription and over-the-counter drugs.

Stability of doxorubicin combined with Radioselectan, a contrast agent, for chemoembolization.

OBJECTIVE: To assess the stability of doxorubicin combined with Radioselectan. METHODS: Solutions of doxorubicin 5 mg/mL were prepared from commercially available 50 mg powder with 10 mL of Radioselectan. They were stored in glass syringes at 4, 25 and 45 degrees C. The concentrations of doxorubicin were determined using a stability-indicating high-performance liquid chromatography method. The initial and final pHs of solutions were compared. The times (t90) needed for doxorubicin to fall to 90% of its initial concentration were calculated by a linear regression analysis. RESULTS: The t90 [95% confidence limits] were 79 [75-83], 56 [53-59] and 22 [21-23] hours for the solutions stored at 4, 25 and 40 degrees C respectively. The initial pH of the solutions stored at 4, 25 and 40 degrees C were 6.52, 6.50 and 6.51 respectively. The final pH of solutions stored at 25 and 40 degrees C decreased significantly by 0.3 and 0.9 respectively. No change of pH solution stored at 4 degrees C was observed. CONCLUSION: Doxorubicin combined with Radioselectan stored at room temperature is stable for 48 h.

[Fast diagnostic tests in the management of group A beta-heamolytic streptococcal pharyngitis]. / Tests de diagnostic rapide dans la prise en charge des angines à streptocoques bêta-hémolytiques du groupe A.

OBJECTIVE: Routine clinical diagnosis of Streptococcus pyogenes in pharyngitis is not always easy. The use in common practice of rapid diagnosis test (RDT), might offer a best control of the antibiotic treatments. The aim of this study is to present seven rapid diagnosis tests, to assess their feasibility and finally to determine the bacteriological correlation. METHOD: We propose to compare the results obtained with seven RDT, and to assess their interest in medical diagnosis for group A streptococcus pharyngitis. A prospective study was conducted for three months, a RDT was performed for children (n=75) between eight and fourteen years old presenting acute pharyngitis. Several throat sampling were performed to order cultures. RESULTS: The group A streptococcus was isolated in 33% (n=25) of throat sampling. Comparing cultures results, and for all studied tests, we obtained comparable performances with manufacturer data, specificity upper than 94% and sensitivity upper than 88%. CONCLUSION: All assessed RDT may offer to physicians a decision-making tool for rapid diagnosis. However, because of its complexity, the agglutination test can be used only in pathology laboratories.