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Biomedical subjects

R Modica

Publications and source records attributed to R Modica.

6 recordsLinked to original sources
PubMed1976

Importance of pharmacokinetic studies on cyclophosphamide (NSC-26271) in understanding its cytotoxic effect.

Pharmacokinetic studies on cyclophosphamide (CP) and its alkylating metabolites produced by hepatic biotransformation have been performed in vivo in animals and in vitro in the perfused liver. CP levels were determined by a gas-chromatographic method combined with mass-spectrometry, and production of alkylating metabolites was assayed by the 4-(4-nitrobenzyl)pyridine reaction for alkylating compounds. Differenes in serum drug levels between normal rats and rats bearing Walker 256 carcinosarcoma were observed in vivo and were confirmed by the liver-perfusion technique. Pharmacokinetic parameters and enzyme kinetic data both in normal and in tumor-bearing animals will be presented. The disappearance of CP and the corresponding formation of CP metabolites was significantly modified when (a) CP was given after previous treatment with a compound which alters its biotransformation (ie, phenobarbital, an inducer of microsomal metabolism), (b) CP was given after previous treatment with CP (which inhibits microsomal metablism), or (c) CP was given with competitive substrates of aldehyde oxidase or dehydrogenase (glyceraldehyde, chloral hydrate, and disulfiram). Results obtained in animals or in the perfused liver will be discussed. The significance of this modified CP metabolism in influencing its cytotoxic effect will be discussed and correlations between drug levels and activity will be presented.

Animals↗
PubMedDate not supplied

[Limitations in the opening of the mouth of an arthrogenic nature].

Mouth opening limitations of arthrogenous nature are subdivided according to a personal schedule into indirect and direct types. The former are brought on by occlusal alterations: these affect articular remodelling and may cause anatomical and functional changes of varying gravity in the temporo-mandibular joint with consequent limitations on opening movements. The latter are the consequence of various pathogenic agents (traumatic, neoplastic, inflammatory, degenerative) originating within the articular structures and developing therein, progressively limiting their function. Some significant personal cases are reported and on the basis of the series the aetiopathogenetic problems of the various forms are discussed, with emphasis on those which represent the basic criteria for therapy.

Adolescent↗
PubMedDate not supplied

[Reimplantation of a mandibular segment resected for the removal of a voluminous osteoma].

Total resection of the host bone for compact voluminous osteoma of the angle and ascending branch of the mandible was followed by immediate reinsertion of the unimpaired segment in its original site. Radiographical check-up 2 yrs later showed that the segment was notably atrophic and flattened, and looked like a long-standing iliac crest graft.

Aged↗
PubMedDate not supplied

[Treatment of follicular cysts of the mandible with reduction cystostomy].

A surgical technique is described for the treatment of a voluminous mandibular cyst whereby the contrasting need to preserve the vitality of the teeth whose apex was near the cyst wall and that of preventing marsupialisation due to the difficulty of providing continuous and effective postoperative care were met by cystotomy with reduction of the primary cyst to a small, periapical cyst. The operation was planned to take place in two stages, the idea being to secure radical removal of the remains of the cyst at a later date. An exploratory inspection after 14 months showed that a bone cavity of negligible size and with no sign of a wall was left. Two objectives were thus achieved: maintenance of the vitality of the teeth around the cyst; improved and spontaneous alignment of the teeth to facilitate and simplify complementary orthodontic management.

Child↗