PubMed HealthSearch

Biomedical subjects

M Chiarotti

Publications and source records attributed to M Chiarotti.

At least 19 recordsLinked to original sources

Effectiveness and side effects of two different doses of caffeine in preventing apnea in premature infants.

The effectiveness of caffeine citrate in preventing idiopathic apnea in premature infants was evaluated. Thirty-seven preterm infants born before the 32nd week of gestation were studied. After an intravenous loading dose of 10 mg/kg of caffeine citrate, two different oral maintenance regimens were followed: 5 mg/kg in Group I and 2.5 mg/kg in Group II. A significant decrease in the number of apneic spells occurred in both treated groups as compared with a control group. In Group II, the frequency of side effects such as tachycardia and gastrointestinal intolerance was significantly lower than in Group I. Group II theophylline plasma levels were significantly lower than those of Group I. The lower Group II theophylline levels presumably explain the reduced frequency of side effects.

Apnea

Pharmacokinetic aspects of caffeine in premature infants.

The pharmacokinetic profile of caffeine was studied in 15 premature infants. Five infants received a single intravenous dose of 10 mg/kg of caffeine citrate 100% at birth and on the 15th day of life. Ten neonates were studied during daily therapy with caffeine for prophylaxis of idiopathic apnea. The time course of plasma and urinary concentrations of caffeine and theophylline shows that caffeine is transformed to theophylline at birth, while total urinary xanthines decrease significantly (p less than 0.001) 72 h after the loading dose given on the 15th day of life. During the whole period of treatment, the decrease in total urinary xanthines and the constant urinary percentage elimination of theophylline are due to further metabolism of theophylline. We confirm that the intravenous loading dose of 10 mg/kg can rapidly obtain therapeutic blood levels of caffeine. We also confirm that the maintenance therapy can be carried out with a single daily dose.

Biotransformation

Analysis of benzodiazepines. II. High-performance liquid chromatography-fluorescence detection after molecular rearrangement to acridanones.

A molecular rearrangement of benzophenones (hydrolysis products of 1,4-benzodiazepines) to 9-acridones has been studied. The compounds synthesized were analysed by high-performance liquid chromatography coupled with a fluorescence detector, because of their high luminescence. The method, which can detect sixteen benzodiazepines simultaneously, is highly sensitive and adequately specific. It is reliable for the analysis of these compounds in biological samples at therapeutic concentrations.

Acridines

Methadone in pregnancy: clinical-toxicological aspects.

The authors describe their experience with methadone treatment in pregnancy. Thirteen abuser pregnant women were studied under defined obstetrical and toxicological protocol. Newborns were also included in this study. In some cases a complete adherence to therapeutic program, allowing labour under very low methadone dosage (5 mg/day), minimized toxicological neonatal risk. Withdrawal syndrome in newborns was well controlled pharmacologically. The role of the toxicological laboratory during clinical management of drug dependent pregnant women is also discussed.

Female

Muscular dystrophy in mice after chronic subcutaneous treatment with cannabinoids.

Swiss male albino mice were treated subcutaneously with the main cannabinoids (CBN, CBD, delta9-THC) at the dosage of 1 mg/kg per day for 30 days, and with the crude resin. At the end of the treatment, after supramaximal stimulation of the sciatic nerve, a significant decrease of both maximal twitch and tetanus tensions was observed in delta9-THC-treated animals; CBD and resin treatment produced some decrease in active tension, while CBN treatment induced an enhancement of the contractile strength. Histology showed lesions interpretable as due to muscular dystrophy. Analysis of protein and hydroxyproline muscular content showed a marked reduction in protein in all treated animals, with a corresponding high increase in hydroxyproline content.

Animals

Methadone extraction from minimal amounts of biological fluids.

A new solid phase extraction method was studied to extract methadone from small amounts of biological samples, by using little disposable columns prepacked with reverse phase sorbents. Two different commercial kinds of reversed phase columns prepacked with octadecylsilane (ODS) were tested; the results were compared to those obtained by a direct liquid/liquid extraction method. Gas chromatograms of extracts obtained by means of ODS reversed phase columns showed a good signal/noise ratio resulting in higher sensitivity (20 ng/ml as detection limit), in comparison with the liquid/liquid extraction method.

Chromatography, Gas

Drugs in hair: a new extraction procedure.

An enzymatic hydrolysis of hair for drug detection is described. The results obtained with the suggested method are compared with those observed by chemical hydrolysis. Enzymatic digestion provides a high recovery (80%) for cocaine metabolite, while alkaline hydrolysis causes its chemical destruction. The two hydrolytic procedures yielded comparable results for morphine. The outlined procedure is recommended when unstable compounds are to be detected in hair.

Cocaine

Comparative analysis of illicit heroin samples.

The comparative analysis of street heroin samples is still an object of scientific discussion. A combination of a wide range of analytical techniques is necessary to obtain a valid amount of information about the sample composition, and it is impossible to define an unique analytical approach. We suggest a complete analytical sequence based on analysis of volatile compounds, opiates, diluents, adulterants and metals, by head space gas chromatography (HS/GC), gas chromatography mass spectrometry (GC/MS), thin layer chromatography (TLC), high pressure liquid chromatography (HPLC) and atomic absorption (AA) using a sample amount as low as 50-100 mg. The outlined procedure can be successfully applied to routine work, thus obtaining suitable information about a sample's chemical composition. This helps to attribute or exclude common sources of separate specimens. Results obtained on 33 street heroin samples confiscated in the metropolitan area of Rome are listed.

Chromatography, Gas