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Biomedical subjects

M Ulgen

Publications and source records attributed to M Ulgen.

At least 37 records · Page 2Linked to original sources
PubMed1994

The effects of the Fränkel's function regulator on the Class III malocclusion.

The material of this investigation consisted of 40 functional Class III malocclusion subjects. Each treatment and control group consisted of 20 Class III cases (10 boys and 10 girls). The mean age of the subjects in the function regulator, FR-3, group was 9.5 years at the beginning of the treatment, and in the control group 9.3 years at the beginning of the observation period. The mean treatment period of the FR-3 group was 1.9 years and the mean observation period of the control group is 1.8 years. In this study, as a result of FR-3 appliance therapy in the functional Class III malocclusion group, the negative overjet that was present at the beginning of the treatment has been converted into a positive overjet by an average increase of 3.8 mm at the end of the treatment. The sum of downward and backward rotation of the mandible, the decrease in the SNB angle with a subsequent increase of the ANB angle, and the retrusion of the lower incisors were effective in the increase of the overjet. The increase in the SNA angle and the protrusion of the upper incisors were found to be insignificant. The overbite decreased due largely to the downward and backward rotation of the mandible.

Cephalometry↗
PubMed1994

The recognition of a diarylimine as a metabonate produced during incubation of N-benzyl-4-chloroaniline with hepatic microsomal preparations.

Evidence is presented for the formation of N-benzylidene-4-chloroaniline as a metabonate during the metabolism of N-benzyl-4-chloroaniline. Control studies suggest that the diarylimine is formed as a chemical artifact from the debenzylation products (benzaldehyde and 4-chloroaniline). This novel observation indicates a possible pathway to amide formation from N-benzylanilines via diarylimines as intermediates.

Aniline Compounds↗
PubMed1994

Metabolic and chemical studies on alpha,N-diarylnitrones.

The metabolism of a number of alpha,N-diarylnitrones has been studied in vitro using male hamster microsomes. All substrates produced benzaldehyde and an uncharacterised substance as metabolites. If the metabolic reaction was carried out in the light, or if the metabolic extracts were exposed to light, the chemical formation of two new compounds was observed. One compound had chromatographic and spectroscopic properties identical to the corresponding amide; the other compound had properties which suggested it was an oxaziridine. The results are discussed in relation to the formation of amides as metabolites of N-benzyl anilines. It is concluded that nitrones are not on the above metabolic pathway, but that they may form amides by chemical rearrangement.

Animals↗
PubMed1994

Structure-activity relationships in the formation of amides from substituted N-benzylanilines.

1. The in vitro hepatic microsomal metabolism of certain substituted N-benzylanilines was studied in the male hamster to establish the mechanism(s) and process(es) involved in the formation of the corresponding amides. 2. N-Benzyl-2,4,6-trihalogeno, N-benzyl-4-cyano- and N-benzyl-4-nitroanilines were only metabolized by N-debenzylation. However, N-benzyl-4-methyl- and N-benzyl-2,4,6-trimethylanilines gave rise to both the corresponding amide and nitrone metabolites together with dealkylation products. These latter two substrates also produced hydroxymethyl metabolites as major products. Metabolism of N-(2,4,6,-trimethylbenzyl)aniline also led to the formation of an amide metabolite. The dealkylation products, the corresponding imine and an unknown metabolite, probably an hydroxylated product were also detected with this substrate. 3. N-(2,4-Dichlorobenzyl) and N-(2,6-dichlorobenzyl) anilines yielded the corresponding nitrone metabolites; but no amide metabolite was detected. Oxidative dealkylation leading to the formation of the corresponding primary anilines and aldehydes, together with para hydroxylation of aniline rings, were established as major routes of metabolism for both compounds. Similarly, neither N-(2,4,6-trifluorobenzyl) nor N-(4-nitrobenzyl) anilines produced any amide metabolite although dealkylation products were detected. 4. The pattern of amide formation observed for these N-benzylsubstituted anilines is discussed in terms of the steric and electronic effects of their aromatic substituents.

Amides↗
PubMed1992

Microsomal formation of N-benzyl-4-hydroxymethylaniline from N-benzyl-4-methylaniline.

The in-vitro metabolism of N-benzyl-4-methylaniline was re-examined using male hamster and rabbit hepatic microsomes; both species generated N-benzyl-4-hydroxymethylaniline, confirmed by TLC and HPLC, comparison with authentic compound. Further confirmation of the formation of this metabolite was achieved by use of a rapid scan UV detector.

Animals↗
PubMed1989

[Effect of cervical headgear therapy on point B in class II, division 1 cases].

The aim of this study is to evaluate the effect of cervical headgear on point B. The study depends on 40 lateral cephalometric films of 20 cases. 10 Class II, 1 cases had undergone cervical headgear therapy (Treatment group) and 10 Class II, 1 cases had received no treatment (Control group). 4 angular and 5 linear measurements were made on the films. By comparing the treatment and control groups, the changes related to growth was eliminated and the following results were obtained; According to SNB angle there was a statistically significant (p less than 0.05) difference between the two groups. SNB angle increased more in the treatment group. But in a measurement which was made to see the linear difference on point B, there wasn't any statistically significant difference between the two groups.

Cephalometry↗
PubMedDate not supplied

Characterization of N-benzylcarbazole and its metabolites from microsomal mixtures by tandem mass spectrometry.

The metabolism of N-benzylcarbazole (NBC) was studied in vitro using hamster hepatic microsomes to establish whether the corresponding amide is formed. This work was carried out in order to see if the extremely low pka characteristic of such a benzylic amine would allow the formation of the carbonyl derivative. No amide formation was observed. However, a number of metabolic products were detected using HPLC, including the oxidative debenzylation products, namely carbazole and benzaldehyde, together with 2 phenolic isomers of NBC. These products were tentatively characterized by their UV spectra using a rapiscan UV detector connected to HPLC equipment. The structural characterization of these 4 metabolites, together with unchanged substrate, was carried out using desorption electron impact tandem mass spectrometry (DEI-MS/MS) on a hybrid instrument with EBQ1Q2 configuration.

Animals↗
PubMedDate not supplied

Studies on the in vitro hepatic microsomal formation of amides during the metabolism of certain secondary and tertiary benzylic amines.

Part of our interest during the last few years has been to investigate the possible intermediate(s) and mechanism(s) involved in the formation of amides from N-benzylic amines. A number of benzylic amines with different aryl and alkyl moieties introduced onto the constituent nitrogen were prepared, thus creating a wide variety of secondary, tertiary and heterocyclic benzylic amines with different logP and pKa characteristics (Tables I & II). In some experiments, the possible intermediates of this reaction, i.e. nitrones (Table III), imines (Table IV) and amides themselves (Table V), were used as substrates in our metabolic studies. Their in vitro hepatic microsomal metabolism was studied in order to obtain a structure/metabolic activity relationship for the formation of amides from benzylic amines. This communication reviews these studies and reports our conclusions as to the mechanism of formation of amides from N-benzylic amines.

Amides↗