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A Triolo

Publications and source records attributed to A Triolo.

9 recordsLinked to original sources
PubMed1992

High-performance liquid chromatographic method for determination of ronactolol in urine and plasma: evaluation of pharmacokinetic parameters in healthy humans.

Ronactolol [(+/-)-4'-[2-hydroxy-3-(isopropylamino)propoxy]-p-anisanilide], a new aminopropanol derivative showing beta-adrenoreceptor blocking activity, was administered orally as capsules to healthy humans at three single doses (30, 60, and 120 mg). Two HPLC methods were developed separately for determination of drug levels in urine and plasma. For plasma samples, after addition of internal standard (IS), a single-step extraction of alkalinized plasma was performed with methylene chloride. The organic layer was evaporated to dryness under reduced pressure, and the residue was taken up and chromatographed on a microbore silica column. Ronactolol and IS were detected by a UV detector at a wavelength of 278 nm. Excellent linearity was observed between the peak height ratios (ronactolol:IS) and concentrations in plasma. The lowest limit of detection (signal:noise, 3:1) was 1.5 ng/mL of plasma. Urine samples were directly injected and chromatographed on a microbore C18 column with an ion-pairing mobile phase. Excellent linearity was observed between the peak areas and concentrations in urine. The lowest limit of detection (signal:noise, 3:1) was 75 ng/mL of urine. The assay was used to determine the main pharmacokinetic parameters in healthy humans.

Adrenergic beta-Antagonists↗
PubMed1992

Simultaneous determination of otilonium bromide and diazepam by first-derivative spectroscopy.

A rapid, simple assay procedure was developed for simultaneous analysis of otilonium bromide, a smooth-muscle relaxant, and diazepam in tablets containing 20 mg of otilonium bromide and 2 mg of diazepam (20:2 tablets) or 40 mg of otilonium bromide and 2 mg of diazepam (40:2 tablets) by "zero-crossing" first-derivative spectroscopy. The tablets were dissolved in 0.01 N HCl, mixtures were centrifuged at 3500 rpm (2472 x g) for 5 min, and first-derivative spectra were recorded. The absolute values of the derivative were measured at 264 nm for determination of otilonium bromide and between 406 and 408 nm (380 nm for analysis of 40:2 tablets) for determination of diazepam. The method is linear, quantitative, and reproducible and can also be used for the tablet dissolution test. Ten tablets of the same batch were analyzed by the described method and by a high-performance liquid chromatographic method, and the results were in good agreement.

Calibration↗
PubMed1991

Analysis of platelet-activating factor by gas chromatography-mass spectrometry: low-energy electron impact of the corresponding 3-acetyl-2-tert.-butyldimethylsilyl derivative.

A method for the analysis of platelet-activating factor in platelets employing gas chromatography and selected-ion monitoring mass spectrometry with low-energy electron impact and stable isotope dilution was developed. The procedure involved Bligh and Dyer extraction of the sample followed by thin-layer chromatographic purification. Platelet-activating factor is successively hydrolysed to the corresponding 2-acetyl-1-O-alkylglycerol by digestion with phospholipase C, and the product is allowed to isomerize to the more thermodynamically stable 3-acetyl-1-O-alkylglycerol before column purification and derivatization of the free OH with tert.-butyldimethylchlorosaline-imidazole. This reagent is of common use in platelet-activating factor derivatization, but is made to react with 2-acetyl instead of 3-acetyl isomer. The advantages of using the latter for the final derivatization are discussed and this method is compared with others currently available for gas chromatographic-mass spectrometric analysis of platelet-activating factor.

Blood Platelets↗
PubMed1991

Gas chromatographic-mass spectrometric determination of two new antimycotic agents, 1-[(5-chloro-2-benzofuranyl)(2-chlorophenyl)methyl]-1H-imidazole and 1-[(5-bromo-2-benzofuranyl)phenylmethyl]-1H-imidazole, in rabbit plasma following topical administration: a preliminary comparison with bifonazole.

A method for the analysis of the antimycotic drugs 1-[(5-chloro-2-benzofuranyl)(2-chlorophenyl)methyl]-1H-imidazole, 1-[(5-bromo-2-benzofuranyl)phenylmethyl]-1H-imidazole and bifonazole in rabbit plasma, employing gas chromatography-mass spectrometry with selected-ion monitoring, was developed. The procedure involved single-step purification of the biological matrix via liquid-liquid extraction on Extrelut columns and use of a carrier substance to minimize the negative effects of adsorption sites during the gas chromatographic process. The limits of detection ranged from 0.1 to 1.4 ng/ml, starting from a 200-microliter sample. The method was applied to a preliminary evaluation of percutaneous absorption of both drugs in the rabbit after a single administration, in comparison with bifonazole.

Administration, Topical↗
PubMed1991

A new glucose clamp algorithm: clinical validation.

A new glucose clamp technique for in vivo studies of insulin sensitivity was validated clinically. Eighteen patients (10 males, 8 females, age 35-80 years, body mass index 34.6-17.04) were connected to a computer-assisted artificial pancreas "Betalike R", using a new algorithm based on a "minimal model", to carry out the glucose clamp technique automatically and especially to overcome the well-known problems of its priming phase. We performed the euglycemic hyperinsulinemic clamp in four patients and the hyperglycemic hyperinsulinemic clamp in 14. In one patient both clamps were done. The mean priming time to reach steady-state glycemia was 20 min. Plasma insulin concentrations were measured every 20 min. This new automatic glucose clamp technique enables the priming phase to be run without any significant overshoot, and accidental variations of glycemia in steady state were reduced to a minimum. The system showed satisfactory safety and stability in controlling the patient's glycemia and assured high speed of the priming phase.

Adult↗
PubMed1991

[Evaluation of a new immunoturbidimetry technique for measuring microalbuminuria].

Subclinical elevation of urinary albumin excretion is a good predictor of later clinical proteinuria. A simple, sensitive and rapid immunoturbidimetric method was developed to quantify urinary albumin excretion (URIN-PAK ImmunoMICRO LAB, Miles Italia Spa). In the presence of polyethylene glycol 6000, immunocomplex between human albumin and its specific antibody are rapidly formed (5-50 min, at room temperature). Absorbance reading are mode U 340 nm (Automatic Analyzer RA 1000, Technicon). The test is specific for albumin failing to cross react with other plasma proteins present in urine, as well as with glibenclamide, chlorpropamide, phenformin, hemoglobin, glucose, urea and thymol. The present method correlates with SCLAVO H-ALBUMIN RIA Kit (r = 0.9917). The test is suitable for clinical use.

Albuminuria↗
PubMed1985

Focal cerebral ischemia: reduction in size of infarcts by ventriculo-subarachnoid perfusion with fluorocarbon emulsion.

A new method for brain resuscitation following acute focal ischemic insult has been developed in this laboratory. The technique utilizes a surrogate route to supply cerebral metabolites and employs highly oxygenated fluorocarbons (OFNS), which are efficient gas transport and exchange agents, perfused through the ventriculo-subarachnoid spaces. We previously described a return of aerobic metabolism and EEG after severe global ischemia by oxygenated perfusions and now report treatment-induced reduction in the size of experienced cerebral infarction. Twenty-eight cats were anesthetized (choralose and urethane), tracheotomized and placed in a stereotactic frame. Physiologic adjustments assured arterial blood pCO2 28-35 Torr, pO2 100-150 Torr pH 7.4 and glucose less than 200 mg%. The left middle cerebral artery was exposed transorbitally and temporarily clipped along with both common carotids for 2 h. One hour later (3 h after ischemic onset) the treated group were perfused by the ventriculo-cisternal route either with OFNS [pO2 = 600 Torr; 3 ml/min 6 h, 2 ml/min 2 h, 1 ml/min 2 h, 0.5 ml/min 2 h at 10 mm Hg intracranial pressure (ICP)] or with the vehicle perfusate. Eighteen to twenty hours after the ischemic insult the animals were sacrificed. Sections of fresh brain of 0.5 mm thickness were incubated in 1% triphenyl tetrazolium chloride. The infarcted areas were confirmed with classic neuropathologic techniques. Areas of infarction (expressed in cm3 and as % of the brain) were measured using a planimeter. OFNS-treated brains contained 80% less infarcted tissue than the vehicle-perfused or untreated stroked animals. The infarcted areas were significantly treatment reduced (P less than 0.05 ANOVA and Bonferroni tests).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗