High-dose intravenous gammaglobulin (HDIVG): therapy of refractory ITP in adults and children

We performed 56 HDIVG administrations in adults (26) and children (30) affected by idiopathic thrombocytopenic purpura with two different schedules: a five-day course at 400 mg/kg/d and a "bolus" 1 gr/kg. Forty-five cases were treated in preparation for surgical operations and eleven for bleeding episodes. Response to the five-day course in adults was good in 3/24, fair in 13/24, poor in 8/24, while in children it was good in 14/26, fair in 9/26, poor in 3/26. The difference between adults and children is statistically significant. None of the responder patients submitted to surgical operation needed platelet infusions during surgery. Response to the "bolus" schedule (6 cases) in adults was poor in 1 case and good in the other one, and in children, fair in 3 cases and good in the other one. In responder patients treated for bleeding episodes we obtained clinical improvement with hemorrhage arrest. In adults the treatment was well-tolerated, while in children we observed 3/30 mild side effects and 1/30 important side effect.

Metabolic fate of zetidoline, a new neuroleptic agent, in man

Healthy volunteers administered orally a single dose (20 mg) of [2-14C]zetidoline, a new dopamine antagonist, exhibited rapid absorption of radioactivity with peak plasma levels of 250-300 ng/ml achieved in 1 h. The compound underwent intensive metabolic first-pass so that plasma radioactivity was represented mostly by two products, metabolite B endowed with neuroleptic activity, and metabolite D inactive, while unchanged zetidoline was not detected. Disappearance of radioactivity from plasma was rapid with a half-life of 1.78 +/- 0.20 h. The simultaneous assay of plasma prolactin showed increased levels of the hormone (+ 464% at the peak time) up to the 6th h after dosing, with plasma concentration profile which mimic those of metabolite B. The radioactive test-dose was eliminated mainly via the kidneys with an average urinary recovery of 84.7 +/- 1.7% in 4 days (73.4 +/- 1.1% within 8 h). The main urinary metabolite (metabolite G) and two minor ones (metabolites B and D) were purified and their structures assigned by IR, MS and NMR spectroscopy, they are: 1-(3-chloro-4-hydroxyphenyl)-3 [2-(3,3-dimethyl-1-azetidinyl)ethyl]imidazolidin-2-one, metabolite B; 1-[2-(3,3-dimethyl-1-azetidinyl)ethyl]-imidazolidin-2-one, metabolite D and the 4'-O-sulphate ester of metabolite B, metabolite G. The metabolic fate of zetidoline in man follows the same phase I reactions demonstrated in rats and dogs, while the phase II reaction is sulphoconjugation instead of the glucuronidation observed in animals.

Metabolism of the neuroleptic agent zetidoline in the rat and the dog

The metabolism of zetidoline, a new neuroleptic, in the rat and the dog has been studied. From the urine of rats and dogs given 5 mg/kg of [2-14C] zetidoline orally, unchanged drug and five metabolites were isolated and the structures of four of them assigned by physicochemical analysis. They are: metabolite B, 4'-hydroxy-3'-chlorophenyl zetidoline; metabolite D, zetidoline without the aryl group; metabolite E, the 6'-hydroxy-4'-beta-D-glucuronide of metabolite B, and metabolite F, the 4'-beta-D-glucuronide of metabolite B. The plasma levels of zetidoline and its metabolites after iv administration show that the drug is rapidly excreted and/or metabolized in both animal species. The plasma radioactivity in the dog consists mainly of the pharmacologically active (neuroleptic) metabolite B, whereas in the rat it consists of the more polar metabolites. After oral administration, elimination in both species occurs mostly via the kidneys. In the dog, within a 24-hr period, 6.2 +/- 0.4% of the dose is accounted for as unchanged zetidoline, 7.6 +/- 0.5% as metabolite B, 10.1 +/- 0.7% as the unidentified metabolite C, and 21.4 +/- 1.1% as metabolite F. In the rat, over the same period, zetidoline is present in traces, metabolite B accounts for 6.9 +/- 0.3% of the dose, metabolite D for 6.6 +/- 0.9%, metabolite E for 15.2 +/- 1.4%, and metabolite F for 31.7 +/- 2.2%.

Structural studies on lipiarmycin. I. Characterization by 1H and 13C NMR spectroscopy and isolation of methyl 2-O-methyl-4-O-homodichloroorsellinate-beta-rhamnoside

1H and 13C NMR spectral studies of lipiarmycin in CDCl3 and in pyridine-d5 provided evidence for the six partial structures I approximately VI and the two sugar units 1 and 2. Acid methanolysis led to the isolation of methyl 2-O-methyl-4-O-homodichloroorsellinate-beta-rhamnoside, whose structure was determined by spectroscopic methods.

Species differences in the disposition and metabolism of 1-methyl-3-(3-pyridyl)-5-(2-hydroxy-methylphenyl)-1H-1,2,4-triazole, a potential sedative-hypnotic compound

1. Disposition and metabolism of 1-methyl-3-(3-pyridyl)-5-(2-hydroxy-methylphenyl)-1H-1,2,4-triazole, a new sedative-hypnotic, were studied in rats (i.v. and p.o.), cats (i.v.) and human volunteers (p.o.) with 14C-labelled drug. 2. In rat and man, the compound is well absorbed, extensively metabolized, and excreted mostly through the kidney; it has short plasma half-lives, 0.6 h in rat, 0.9 h in man, and 1.9 h in cat. 3. In rat and man metabolism involves N-oxidation of the pyridine ring (Metabolite I), and in cat oxidation of the hydroxymethyl group (Metabolite II). Four other conjugated metabolites (III-VI) isolated from rat urine and bile, and from urine of cats and man, have been characterized. 4. The unchanged compound, but not its metabolites, crosses the blood-brain barrier in rat and cat. 5. The species differences in the disposition and metabolism of the compound are consistent with previous pharmacological data indicating a greater and more prolonged effect in cat.

Metabolism of deflazacort in the rat, dog and man

The metabolism of [2'-14C]deflazacort, (11 beta, 16 beta)-21-(acetoxyl)-11-hydroxy-2'-methyl-5'H-pregna-1, 4-dieno[17,16-d]oxazole-3,20-dione, orally given to rats, dogs, and humans, has been studied. From the urine of the three species and from rat bile and liver preparations, five main metabolites I-V have been isolated and their structures investigated by physicochemical analysis: 1,(5 beta,11 beta,16 beta)-11,21-dihydroxy-2'-methyl-5'H-pregn-1-eno[17,16-d]oxazole-3,20-dione; II, (11 beta,16 beta)-11,21-dihydroxy-2'-methyl-5'H-pregna-1,4-dieno[17,16-d]oxazole-3,20-dione; III, (6 beta,11 beta,16 beta)-6,11,21-trihydroxy-2'-methyl-5'H-pregna-1,4-dieno[17,16-d]oxazole-3,20-dione; IV, (3 epsilon,11 beta,16 beta)-3,11,21-trihydroxy-2'-methyl-5'H-pregn-5-eno[17,16-d]oxazol-20-one. Metabolites II and III are quantitatively the most important in the urine of the rat, dog, and man; metabolite V, whose structure is uncertain, has been found in human and rat urine. In the formation of metabolites I-V the fused 2-methyloxazoline ring is unmetabolized, whereas the steroid moiety follows the general metabolic pathways reported for other related corticosteroids.

New antibiotics from Actinoplanes strains. Structure of A 17002 C

A 17002 C is a new metabolite produced by Actinoplanes strains, structurally related to the virginiamycin factor M. On the basis of physico-chemical data, MS, IR, 1H and 13C NMR, structure I is assigned to A 17002 C.

The use of electrical geophysical techniques for the development of groundwater supplies in South African National Parks

Geo-electrical investigations have been carried out along the Nossob River in the Kalahari Gemsbok National Park and in the Nwanedzi area of the Kruger National Park. The object of these investigations was to locate potable groundwater supplies with a greater degree of accuracy than the random drilling of boreholes was able to do. The successful completion of the investigations has proved that when correctly applied the geo-electrical technique is a valuable aid to locating favourable target zones for groundwater development, thus resulting in considerable economic benefits.

Metabolites of 3-hydrazino-6-[bis-(2-hydroxyethyl)amino]pyridazine dihydrochloride in rat urine

In 24 hr urine of rats orally given 150 mg/kg of 3-hydrazino-6-[bis-(2-hydroxyethyl)amino]pyridazine dihydrochloride (DL 150), no unchanged compound was detected. Three metabolites, less polar than DL 150, were isolated, their structures assigned by UV, MS, IR and 1H NMR spectroscopies, and confirmed by synthesis. They are: 3-[bis-(2-hydroxyethyl)amino]-6-isopropoxypyridazine (1); 3-[bis-(2-hydroxyethyl)amino]pyridazine (2); 3-methyl-6-[bis-(2-hydroxyethyl)amino]-s-triazolo[4,3-b]pyridazine (3). The metabolism of DL 150 in the rat follows some of the metabolic pathways reported for hydralazine.

Rifamycin R, a novel metabolite from a mutant of Nocardia mediterranea

Rifamycin R is a novel ansamycin produced by a mutant of Nocardia mediterranea; both physical and chemical data indicate that it is 30-demethyl-30-hydroxymethyl rifamycin S.

Metabolism of 5-isopropyl-1-methyl-2-nitro-1H-imidazole. Identification of some urinary metabolites in the dog

The metabolism of 5-isopropyl-1-methyl-2-nitro-1H-[2-14C] imidazole in dogs has been investigated after oral administration of 50 mg/kg. Three main metabolites, still containing the nitro group and accounting for about 50% of the total radiocarbon, together with a small amount of the unchanged drug, were isolated from the urine within 48 hr. The structures were determined by mass, infrared, and nuclear magnetic resonance spectroscopy. The biotransformations giving rise to the metabolites isolated involve the isopropyl chain of the molecule, either at the tertiary carbon atom or at one of the two methyl groups, or both. Thus, the metabolic behavior of this 2-nitroimidazole derivative appears to be similar to that previously demonstrated for the class of the isomeric 5-nitroimidazoles.

Isolation and structure determination of a further metabolite of diftalone

A further metabolite of diftalone, a new antiinflammatory drug, has been identified as 7,14-dihydroxyphthalazino [2,3-b] phthalazine-5,12(7H,14H)-dione, on the basis of physico-chemical properties. The free metabolite was isolated from guinea-pig urine, where it is present as such and as the beta-glucuronide. This structure confirms the selective susceptibility of the methylene group of diftalone towards biological hydroxylation.

Ansamycin biogenesis: studies on a novel rifamycin isolated from a mutant strain of Nocardia mediterranei

A novel ansamycin, rifamycin W, was isolated from a mutant strain of Nocardia mediterranei. The metabolic origin of rifamycin W was studied by (13)C nuclear magnetic resonance spectroscopy. Examination of the proton-decoupled pulse and Fourier transform (13)C spectra of rifamycin W biogenetically enriched with [1-(13)C]-, [2-(13)C]-, and [3-(13)C]propionate and with [1-(13)C]acetate has revealed that the alignment of acetate and propionate units corresponds to that previously proposed for rifamycin S. Washed mycelium from a rifamycin B-producing strain of N. mediterranei transformed rifamycin W into rifamycin B. We suggest that rifamycin W is a normal intermediate in the biosynthesis of the other rifamycins. These results, together with the structural similarity of rifamycin W to the streptovaricins, reinforce our hypothesis that a common progenitor is involved in the biogenesis of all naphthalenic ansamycins.