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Biomedical subjects

M Riva

Publications and source records attributed to M Riva.

At least 109 records · Page 6Linked to original sources
PubMed1984

[N-acylated derivatives of cyclohexylaniline with potential antiallergic and analgesic-antiinflammatory activity].

Some N-acylated derivatives of cyclohexylaniline were prepared. These can be considered as derived from oxarbazol (A), a carbazolic structure with antiallergic activity, by breaking the bond between carbon atom 4a and 4b. In the new molecule the following groups were introduced: benzoic acid, salicylic acid, acetylsalicylic acid and tetrazol. The synthesized compounds were studied for analgesic, antiedema and antiallergic activity. Some showed analgesic action (phenylquinone) comparable with that of naproxen. Antiinflammatory activity was slight and antiallergic activity nonexistent.

Aniline Compounds↗
PubMed1982

Natural variation in yeast RNA polymerase A. Formation of a mosaic RNA polymerase A in a meiotic segregant from an interspecific hybrid.

There is a natural variation in the molecular structure of RNA polymerase A isolated from several genetically distant yeast species, Saccharomyces cerevisiae, Saccharomyces douglasii, Schizosaccharomyces pombe, and Candida tropicalis. Several biochemical criteria were used to identify their homologous polypeptide components. Based on these correlations, the minimal subunit composition of S. cerevisiae (and Saccharomyces carlsbergensis) RNA polymerase A was tentatively defined as A190, A135, A40, A27, A23, A19, and A14.5. Without the two Saccharomyces species, S. cerevisiae and S. douglasii, 7 of 13 polypeptides of enzyme A(A49, A43, A40, A34.5, A19, A14.5, and A14) differ slightly in molecular weight and can be resolved by electrophoresis on polyacrylamide gel. The RNA polymerase A isolated from the diploid interspecific hybrid contains all the polypeptides characteristic of the two parents. One meiotic segregant had a hybrid RNA polymerase A with five of the polymorphic polypeptides (A49, A43, A19, A14.5, and A14) coming from S. douglasii and two (A40 and A34.5) from S. cerevisiae. In three successive backcrosses with S. cerevisiae, all the genes for S. douglasii polypeptides were shown to recombine although parental ditype tetrads predominated in the four four-spored asci examined. Thus, the genes for the seven polymorphic polypeptides are not clustered: they lie on at least three different chromosomes.

Ascomycota↗
PubMed1982

[Derivatives of 4-phenylcyclohexylethylamine with antidepressive activity].

Several new derivatives of trans-1-(4-phenylcyclohexyl)-ethylamine (M.G. 6669) have been synthesized with various substituents at the alpha-carbon and/or at the amine nitrogen atom. All compounds were evaluated for a potential antidepressant activity taking M.G. 6669 as reference. They turned out to be less active than the reference substance. Pharmacological evaluation of M.G. 6669 itself was broadened during this work. The good antidepressant properties of this compound were confirmed, accompanied however by some toxic phenomena.

Aggression↗
PubMed1981

[Heterocyclic compounds containing the residue of a 4-aminophenylalkanoic acid with potential anti-inflammatory activity. IV. Derivatives of 2-phenyl-2H-indazole].

Numerous derivatives of 2-phenyl-2H-indazole were prepared. The compounds were of general formula I: where R is an acid, neutral or basic radical and R1, R2, R3 represent various functional groups, hydrogen atom or chlorine. The compounds were examined for analgesic-antiinflammatory properties and in some cases as inhibitors of platelets aggregation. Among the compounds where R is an alkanoic acid residue, the only compound showing interesting activity was M.G. 18755 [R = CH(CH3) COOH; R1, R2, R3 = H] and its lysine salt (M.G. 18334), which in various tests showed activity greater than that of ibuprofen. The homologous butyric derivative (M.G. 18860) showed a good anti-aggregatin activity.

Animals↗
PubMed1979

Synthesis and pharmacological properties of 3-O-derivatives of 1,2,5,6-di-O-isopropylidene-alpha-D-glucofuranose.

A series of 3-O-derivatives of 1,2,5,6-di-O-isopropylidene-alpha-D-glucofuranose were prepared and tested for their pharmacological activity in comparison with tribenoside, a well known drug structurally related, and with other anti-inflammatory agents. Almost all the compounds had a very low toxicity and few of them showed a notable antiinflammatory and antipyretic activity and were able to clearly decrease the venous wall permeability.

Analgesics↗
PubMed1979

Residual corneal astigmatism after perforating keratoplasty.

A statistical analysis was made of post-operative astigmatism after perforating keratoplasty in subjects with various corneal diseases. A total of 100 cases were analyzed on discharge (25th day) and 6 months after surgery. The degree of astigmatism and its time course was assessed, and its effect on post-operative visual acuity was investigated, including any changes resulting from removal of the continuous suture. Mean astigmatism values were 4 dioptres on discharge and 4.2 dioptres after 6 months. No statistically significant relation was found between degree of astimatism and recovery of visual acuity.

Adolescent↗
PubMed1979

New cephalosporins and 7 alpha-methoxy cephalosporins. Chemistry and biological activities.

The synthesis and the in vitro activity of a number of cephalosporins and 7 alpha-methoxy cephalosporins having 7-acyl substituents derived from 1-methyl-4 (or 5)-nitro-1H-imidazolyl-thioacetic acids are described. The microbiological profile is influenced by the position of both the nitro group and the side-chain sulfur atom on the 1-methyl imidazole, and by the nature of the 3-substituent.

Bacteria↗
PubMed1977

Synthesis and topical antiinflammatory properties of 17,21-bis(acetyloxy)-6beta,9-difluoro-11beta-hydroxypregna-1,4-diene-3,20-dione and related 2-halogenated compounds.

Introduction of a halogen atom at C-2 of steroid 3-ketofluorohydrins, obtained from the corresponding 5alpha,6alpha-epoxides by trans-diaxial opening with hydrofluoric acid, prevents the 6beta-fluorine atom from undergoing rearrangement to the more stable 6alpha configuration when the 5-tert-hydroxyl is split off to yield to yield a conjugated double bond. Two processes were investigated for the synthesis of 17,21-bis(acetyloxy)-6beta-fluoro-1,4,9(11)-triene-3,20-dione (24a) and the related 2-bromo compound 24b starting from the known 21-(acetyloxy)-6beta-fluoro-5alpha,11alpha,17-trihydroxypregnane-3,20-dione (13). Successive reaction with hypobromous acid, epoxidation, and fluorination converted 24a and 24b into the title compound 27a and the analogue 2-bromo compound 27b. In addition, a synthesis of 17,21-bis(acetyloxy)-2-chloro-6beta,9-difluoropregna-1,4-diene-3,20-dione (27c) is reported. The antiinflammatory activity of 17,21-bis-(acetyloxy)-6beta,9-difluoropregna-1,4-diene-3,20-dione (27a) and its 2-halogenated analogues 27b and 27c in comparison with the corresponding 6alpha,9-difluoro epimers was studied. Some 6beta-fluoro compounds displayed high topical antiinflammatory activity without systemic effects.

Administration, Oral↗
PubMed1977

Derivatives of 2-bromo-6beta-fluoropregna-1,4-diene-3,20-dione and their antiinflammatory activity.

As part of a systematic study of the effects of chemical modifications on the antiinflammatory activity of 17,21-bis(acetyloxy)-2-bromo-6beta,9-difluoro-11beta-hydroxypregna-1,4-diene-3,20-dione (halopredone acetate, Topicon), a new potent antiinflammatory, a series of derivatives of 2-bromo-6beta-fluoropregna-1,4-diene-3,20-dione was prepared for pharmacological screening. Different synthetic approaches are described. All the synthesized compounds had topical antiinflammatory activity, with no side effects, but were lower in activity than halopredone acetate. Most of them showed topical antiinflammatory activity comparable to that of fluocinolone acetonide. Only two of the synthesized compounds were found to have systemic anti-inflammatory activity comparable to that of betamethasone.

Animals↗
PubMed1977

Pharmacology of halopredone acetate, a new topical antiinflammatory steroid.

The topical antiinflammatory activity of 17,21-bis(acetyloxy)-2-bromo-6beta,9-difluoro-11beta-hydroxypregna-1,4-diene-3,20-dione (halopredone acetate; Topicon) has been compared with those of other steroids in a few bioassays in animals. At variance with the reference compounds, halopredone acetate, which exhibited variable potency according to the assay used never displayed substantial systemic effects when locally applied. Even after subcutaneous administration this new steroid did not interfere with adrenal function, carbohydrate and protein metabolism or sodium and potassium excretion. On the basis of the results reported, halopredone acetate may be considered a steroid with potentially high topical antiinflammatory activity and good tolerability.

Administration, Topical↗
PubMed1976

Basic derivatives of 6,7-dihydroindolo(1,7-ab)(1) benzazepine and 6H-indolo(7,1-cd)(1,5) benzoxazepine as potential antidepressant agents.

Basic derivatives of 6,7-dihydroindolo[1,7-ab][1]benzazepine and 6H-indolo[7,1-cd][1,5]benzoxazepine incorporating the imipramine basic side chain were synthesized and screened for antidepressant activity in mice. With few exceptions, the compounds unsubstituted at C-2 antagonized reserpine-induced ptosis and hypothermia showing negligible anticholinergic and antihistaminic properties. The compound 1-[2-(N-methyl-N-benzylamino)ethyl]-6,7-dihydroindolo[1,7-ab][1]benzazepine had the highest toxicity-activity ratio.

Animals↗
PubMed1976

Influence of side chain configuration on anti-inflammatory analgesic and anti-pyretic properties of 4-biphenylyl alkanoic acids.

A study on the influence of the number of carbon atoms in the side chain as well as side chain configuration on some pharmacologic properties of 4-biphenylyl alkanoic acids is presented. Unlike the chemical structure dependent anti-inflammatory properties, mild analgesic and anti-pyretic properties were neither dependent upon number of carbon atoms nor side chain configuration.

Analgesics↗
PubMed1975

Pharmacological properties of n1-piperonyl-n4-3,7,11-trimethyl-2,6,10-dodecatrienyl-piperazine, a new non-anticholinergic gastric antisecretory agent.

The special and general pharmacology of N1-piperonyl-N4-3,7,11-trimethyl-2,6,10-dodecatrienylpiperazine (U-27) is reported. According to the results of the animal experiments the compound turned out to be a well tolerated gastric antisecretory drug devoid of anticholinergic activity. The compound was able to prevent hypersecretion induced by pylorus ligature in rat and guinea pig. Its duration of action was remarkable and no tolerance occurred after a repeated treatment. The compound displayed also an interesting activity on several experimental ulcers.

Animals↗