Determination of levocetirizine in human plasma by liquid chromatography-electrospray tandem mass spectrometry: application to a bioequivalence study.

We describe a liquid chromatography-tandem mass spectrometric method (LC-MS/MS) for levocetirizine quantification (I) in human plasma. Sample preparation was made using a fexofenadine (II) addition as internal standard (IS), liquid-liquid extraction using cold dichloromethane, and dissolving the final extract in acetonitrile. I and II (IS) were injected in a C18 column and the mobile phase composed of acetonitrile:water:formic acid (80.00:19.90:0.10, v/v/v) and monitored using positive electrospray source with tandem mass spectrometry analyses. The selected reaction monitoring (SRM) was set using precursor ion and product ion combinations of m/z 389>201 for I and m/z 502>467 for II. The limit of quantification and the dynamic range achieved were 0.5ng/mL and 0.5-500.0ng/mL. Validation results on linearity, specificity, accuracy, precision and stability, as well as its application to the analysis of plasma samples taken up to 48h after oral administration of 5mg of levocetirizine dichloridrate in healthy volunteers demonstrate its applicability to bioavailability studies.

[Geographic distribution of planorbidae in Santa Catarina, Brazil]. / Distribuição geográfica de planorbídeos em Santa Catarina, Brasil.

A revision of the malacological surveys carried out in Santa Catarina, Brazil, by the National Health Foundation in 52 counties of 8 microregions between 1981 and 1994 was made. Fifty of them were positive for Biomphalaria tenagophila, the only schistosome vector identified in the 94,535 specimens collected. Of 1,358 districts, 617 (45.4%) were positive to the vector, varying from 4.3% to 89.4% per municipality. The percentages of water bodies with planorbids varied from 0.2% to 26.3% and, of the total 28,120 examined 2,013 (7.1%) were positive. Snails infected with cercariae of Schistosoma mansoni were found in the counties of Araquari, Massaranduba, Joinville, Jaraguá do Sul and São Francisco do Sul, the last two constituting the southernmost focus of schistosomiasis mansoni in Brazil. Other planorbid species identified were B. peregrina, B. oligoza, B. schrammi, B. straminea and B. occidentalis.

Plasma amino acid patterns in alcoholic pellagra patients.

Plasma amino acid concentrations in 33 male alcoholic patients with pellagra (age 20-68 years) were compared with those in 17 healthy male subjects (age 20-45 years). Pellagra diagnosis was made on the basis of the typical clinical skin picture, and low urinary excretion of N'methylnicotinamide and N'methyl-2-pyridone-5-carboxamide (reduced by 70 and 80%, respectively, compared with controls). There were significant differences in body mass index, creatinine/high index and serum albumin between the two groups, indicating that besides pellagra the alcoholic patients had some degree of malnutrition. Of 17 plasma amino acids measured, the following had significantly lower concentrations in the pellagrins: tryptophan (3.65 vs 5.93 mumol/dl, pellagrin vs control), isoleucine (6.31 vs 11.13), leucine (11.54 vs 24.19), lysine (16.25 vs 34.47), methionine (2.61 vs 4.22), phenylalanine (5.71 vs 9.23), threonine (13.29 vs 26.81), valine (17.60 vs 41.06), alanine (42.54 vs 70.87), arginine (5.87 vs 10.09), tyrosine (5.57 vs 9.30). Glutamic acid was significantly higher in the pellagrins (18.45 vs 9.49). There was no difference between the groups of aspartic acid, glycine, histidine, proline and serine concentrations. It is concluded that pellagra is an important factor influencing the amino acid profiles in these patients. This finding should be taken into account when using plasma amino acid levels to assess the clinical status of the pellagrin.

Effect of acute glucose infusion on plasma levels of insulin, glucose and free fatty acids, and on the glucose removal rate in obese women

The objective of the present study was to report the variations in levels of insulin, free fatty acids and glucose occurring in a group of obese and nonobese women after acute intravenous glucose infusion. The difference between glucose and insulin levels in obese and nonobese women in response to glucose infusion was statistically significant. The mean maximum value for glucose detected in the obese group was 256 mg/dl versus 283 mg/dl in the nonobese group (p < 0.05). Insulin content was 147 muU/ml in the obese group versus 36 muU/ml in the nonobese group (p < 0.05). K (fractional removal rate constant for glucose) values were similar in both groups suggesting that the higher glucose and insulin peaks showed by the obese were due to the higher glucose uptake by the blood rather than its removal impairment.