Biomedical subjects

F Rossi

Publications and source records attributed to F Rossi.

At least 469 records · Page 26Linked to original sources

PubMed1992

4H-thieno[3,4-c]pyrazole derivatives with antiinflammatory, analgesic, antipyretic and platelet antiaggregating activities.

The synthesis of a series of 1-aryl-1,6-dihydro-4H-thieno[3,4-c]pyrazol-4-ones by cyclization of 3-[(2-arylhydrazino)methylene]thiophene-2,4(3H,5H)-diones, prepared by reacting 3-dimethylaminomethylenethiophene-2,4(3H,5H)-dione with arylhydrazines, is described. The 4-fluorophenyl derivative showed remarkable analgesic, antiinflammatory and antipyretic activities in mice or rats, as well as a platelet antiaggregating activity in vitro comparable to that of acetylsalicylic acid.

Acetates↗

PubMed1992

Clinical pharmacokinetics of teicoplanin and aminophylline during cotreatment with both medicaments.

The influence of teicoplanin and aminophylline (theophylline ethylenediamine) on their mutual steady-state pharmacokinetics was studied in two parts, namely experimental and clinical studies. The concentrations of teicoplanin and aminophylline (theophylline) were evaluated at several times after intravenous administration of teicoplanin (3 and 15 mg/kg) and aminophylline (5 mg/kg) in 12 rabbits. Ten COPD patients were treated for 5 consecutive days with a short-term intravenous infusion of 240 mg aminophylline twice daily; ten more patients received for 5 days a short-term intravenous infusion of 200 mg teicoplanin twice daily. On the last day, blood samples were taken for teicoplanin and theophylline determination by means of the HPLC method. Subsequently, while aminophylline and teicoplanin were continued at the same dosage, the first ten patients received in addition a short-term intravenous infusion of 200 mg teicoplanin twice daily, and the second ten patients a short-term intravenous infusion of 240 mg aminophylline twice daily. After 5 days the serial assays of serum teicoplanin and theophylline were repeated. Our results demonstrated, in both experimental and clinical studies, no influence of theophylline on the steady-state pharmacokinetics of teicoplanin. Likewise teicoplanin had no significant effect on the steady-state pharmacokinetics of intravenous administration of theophylline in the form of aminophylline.

Aged↗

PubMed1992

Antiflammins suppress the A23187- and arachidonic acid-dependent chloride secretion in rabbit distal colonic mucosa.

Antiflammins are synthetic peptides with sequence homology to proteins inhibitory for phospholipase A2. The effects of antiflammins on chloride secretion induced by the calcium ionophore A23187, arachidonic acid (AA) and prostaglandin E2 (PGE2) were investigated in distal rabbit colonic mucosa mounted in Ussing-type chambers. 100 nM AF-2 (antiflammin 2, peptide HDMNKVLDL) fully prevented the increase in Isc, net chloride secretion, tissue PGE2 and second messenger cAMP induced by 5 microM A23187. AF-1 (antiflammin 1, peptide MQMKKVLDS) also inhibited, although to a lesser extent, the A23187-mediated increase in Isc. AF-2 inhibition began at doses of 100 nM (delta Isc -0.20 +/- 0.08, microEq h-1 cm-2, mean +/- S.E.M., N = 3) and was maximal at doses comprised between 200 and 250 nM (delta Isc -0.51 +/- 0.12, microEq h-1 cm-2, mean +/- S.E.M., N = 3). AF-2 also inhibited the increase in Isc and chloride secretion induced by the incubation with 10 microM AA and bradykinin but it was ineffective when tissues were stimulated with 10 microM PGE2. 100 nM AF-2 brought about an inhibition of the increase in AA-mediated increases in PGs and cAMP comparable to that of 10 microM of the cyclooxygenase inhibitor indomethacin. In vitro assay of colonic cyclooxygenase activity showed that 100 nM AF-2 and AF-1 inhibited cyclooxygenase activity (73 and approximately 30%, respectively), but they did not modify the in vitro activity of porcine phospholipase A2.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗

PubMed1992

Effects of tetanus toxin, Salmonella typhimurium porin, and bacterial lipopolysaccharide on platelet aggregation.

Endotoxins may interfere with platelet aggregation by interacting with the platelet membrane. The aim of this study was to evaluate the effects of tetanus toxin, Salmonella typhimurium porin, and bacterial lipopolysaccharide (LPS) on platelet aggregation induced by ADP and thrombin in vitro. Spontaneous platelet aggregation and platelet aggregation induced by ADP and thrombin were measured. Our results show that Salmonella typhimurium porin and bacterial LPS enhanced human and rabbit platelet aggregation induced by ADP and thrombin. Tetanus toxin did not affect platelet aggregation.

Animals↗

PubMed1992

Effects of gadolinium on N-methyl-D-aspartate (NMDA)-induced centrogenic arrhythmias.

In urethane-anesthetized rats, the intracerebroventricular (i.c.v.) administration of N-methyl-D-aspartate (NMDA)-induced central arrhythmias. These cardiac rhythm disorders could be prevented by the i.c.v. microinjection of gadolinium, an inhibitor of exocytosis. These findings suggest that inhibition of central neurotransmitter exocytosis could protect against centrogenic arrhythmias.

Anesthesia↗

PubMed1992

omega-Dialkylaminoalkyl esters of N-phenyl aminethiocarboximidic acids with local anesthetic and other activities.

A series of omega-dialkylaminoalkyl esters of N-phenyl aminethiocarboximidic acids was prepared by reaction of N-phenyl 1-pyrrolidine, 1-piperidine, 4-morpholine, 1,2,3,4-tetrahydro-1-quinoline, 1,2,3,4-tetrahydro-2-isoquinoline, 10-phenothiazine, N-phenyl-2-pyridylamine and N-benzyl-2-pyridylamine-carbothioamides (prepared in situ from the appropriate secondary amine and phenyl isothiocyanate) with a number of omega-chloroalkyldialkylamines in anhydrous DMF or THF solution in the presence of sodium hydride. Good yields of the above esters were obtained provided that sodium hydride was added initially or after the formation of 3,3-disubstituted 1-phenylthiourea, according to the nature of the secondary amine. Some esters showed in mice local anesthetic activity comparable with that of lidocaine, as well as moderate hypoglycemic, antiarrhythmic, analgesic, antiacetylcholine, H1-antithistamine and platelet antiaggregating activities.

Acetylcholine↗

PubMed1992

4-substituted 1-methyl-1H-indazoles with analgesic, antiinflammatory and antipyretic activities.

The synthesis of [(1-methyl-1H-indazol-4-yl)oxy]acetic acid 4, 1-methyl-1H-indazole-4-acetic acid 9, 2-(1-methyl-1H-indazol-4-yl)propanoic acid 15 and [[(1,5,6,7-tetrahydro-1-methyl-4H-indazol-4-ylidene)amino]oxy]acet ic acid 16, as well as of amides and esters derived from 4 and 9, starting from 1,5,6,7-tetrahydro-1-methyl-4H-indazol-4-one is described. Some of the above compounds showed weak antiinflammatory, analgesic, antipyretic and hypotensive activities in rats and mice, as well as moderate platelet antiaggregating effects in vitro.

Animals↗

PubMed1992

Research on heterocyclic compounds. XXX. Synthesis and pharmacological activity of 2-methylimidazo[1,2-b]pyridazine-3-carboxylic acids.

A group of ethyl 2-methylimidazo[1,2-b]pyridazine-3-carboxylates were prepared by reaction in anhydrous ethanol of some substituted 3-amino-pyridazines with ethyl 2-chloroacetoacetate. The corresponding carboxylic acids were obtained via alkaline or acid hydrolysis and then tested both in vivo to evaluate their antiinflammatory, analgesic and ulcerogenic actions and in vitro for their ability to inhibit the prostaglandin biosynthesis. The pharmacological results are discussed in terms of both structure-activity relationships and mechanism of action.

Animals↗

PubMed1992

Photosensitizing activity of water- and lipid-soluble phthalocyanines on prokaryotic and eukaryotic microbial cells.

The photosensitizing activity of lipophilic zinc-phthalocyanine (Zn-Pc) and its water-soluble sulphonated derivative (Zn-PcS) towards Streptococcus faecium and Candida albicans was studied and correlated with the amount of cell-bound photosensitizer. With both micro-organisms Zn-PcS was more tightly bound in larger amounts than Zn-Pc in the protoplasts of the cytoplasmic membrane. As a consequence, the photoinduced damage in S. faecium initially involved membrane proteins, while DNA was modified only upon prolonged irradiation. For C. albicans only Zn-PcS showed a preferential affinity for the spheroplasts and the decrease in cell survival was not accompanied by detectable modifications of the electrophoretic pattern of membrane proteins. The photoinduced ultrastructural alteration of both micro-organisms suggests damage at membrane level. This would indicate the involvement of different targets in bacteria and yeast for phthalocyanine photosensitization.

Candida albicans↗

PubMed1992

[Cocaine: the historical aspects].

The habitual use of drugs acting on the human mental faculties is very ancient. An overview on the history of cocaine, from the pre-Colombian populations of South-America to our days, is reported.

Cocaine↗

PubMed1992

Effects of flunoxaprofen, a non-steroidal anti-inflammatory agent, on the cardiovascular system.

The effects of flunoxaprofen (FL) were investigated using anesthetized normotensive and spontaneously hypertensive (SHR) young and old rats. The animals were divided into two groups. One group received a non-steroidal anti-inflammatory agent at doses significantly inhibiting prostaglandin (PG)-cyclooxygenase; the other received no non-steroidal anti-inflammatory drugs. Oral pretreatment of anesthetized rats with flunoxaprofen (6.6, 11.5, and 19.9 mg/kg/day in the feed for 560 days) significantly increased the following responses: occlusion of the common carotid arteries, and reactivity to L-noradrenaline (NA) (i.v.), and angiotensin II (Ang) (i.v.). Pressor responses also increased in normotensive and in SHR rats treated with FL (20 mg/kg/day for seven days). The effects were more intense in the SHR rats. Moreover, oral pretreatment of normotensive rats with FL (20 mg/kg/day for seven days) partially yet significantly reduced the antihypertensive activity of etozolin (ET), a diuretic and antihypertensive drug. Our data confirm the important role of prostaglandins in the regulation of the cardiovascular system, and an increase in arachidonic acid metabolite biosynthesis with vasodilatory effects being part of the mechanism of action of some antihypertensive drugs.

Administration, Oral↗

PubMed1992

Central arrhythmogenic effects of N-methyl-D-aspartate (NMDA) in anesthetized rats: influence of the denervation of the carotid-sinus baroreceptors on the susceptibility to arrhythmias.

The intracerebroventricular (i.c.v.) administration of NMDA into urethane anesthetized rats could induce centrogenic cardiac arrhythmias. There were some important differences between sodium glutamate- and NMDA-induced arrhythmias which rendered it difficult to accept the assumption that glutamate-induced arrhythmias were due to the stimulation of only NMDA receptors. Denervation of the carotid-sinus baroreceptor zones enhanced the central arrhythmogenic activity of both sodium glutamate and NMDA.

Anesthesia↗

PubMed1992

3,5-Diphenyl-1H-pyrazole derivatives. X. N-substituted 1-(2-aminopropyl)- and 1-(3-amino-2-hydroxypropyl)-3,5-diphenyl-1H-pyrazoles with antiinflammatory and other activities.

The syntheses of 1-(2-hydroxypropyl)-3,5-diphenyl-1H-pyrazole 1 by reaction of 1-hydrazino-2-propanol with dibenzoylmethane and of N-substituted 1-(2-aminopropyl)-3,5-diphenyl-1H-pyrazoles 3 by reaction of primary and secondary amines with the tosylate of 1, as well as of N-substituted 1-(3-amino-2-hydroxypropyl)-3,5-diphenyl-1H-pyrazoles 6 starting from 3,5-diphenyl-1H-pyrazole, are described. Some compounds 3 and 6 showed remarkable antiinflammatory activity in rats, as well as weak analgesic, antipyretic, antiarrhythmic, hypotensive activities in mice and rats and moderate platelet antiaggregating effects in vitro.

Animals↗

PubMed1992

N-substituted O-(3-amino-2-hydroxypropyl)oximes of 1,3,3-trimethyl-5-endo-(1-piperidinyl or 4-morpholinyl)-2-oxabicyclo [2.2.2]-octan-6-ones with platelet antiaggregating and local anesthetic activities.

The synthesis of a series of N-substituted O-(3-amino-2-hydroxypropyl)oximes of 1,3,3-trimethyl-5-endo-(1-piperidinyl or 4-morpholinyl)-2-oxabicyclo [2.2.2]octan-6-ones is described. Some of these ethers showed strong local anesthetic activity in mice and platelet antiaggregating activity in vitro comparable to that of acetylsalicylic acid, as well as moderate hypotensive, antiarrhythmic and analgesic activities in rats and mice.

Analgesics↗

PubMed1992

Cyclohepta[b]pyran derivatives with platelet antiaggregating and other activities.

The synthesis of some N,N-disubstituted 4-amino-6,7,8,9-tetrahydro-3-phenylcyclohepta[b]pyran-2(5H)-ones by reaction of phenylchloroketene with a series of N,N-disubstituted 2-aminomethylenecycloheptanones, followed by dehydrochlorination of the primary adducts with DBN, is described. Some compounds showed a platelet antiaggregating activity in vitro superior or comparable to that of acetylsalicylic acid, as well as weak local anesthetic, antiinflammatory and analgesic activities in mice and rats.

Analgesics↗

PubMed1992

3,5-Diphenyl-1H-pyrazole derivatives. IX. 2-substituted 4-phenyl-5-(3,5-diphenyl-1H-pyrazol-1-yl) pyrimidines with platelet antiaggregating and other activities.

The synthesis of 2-substituted 4-phenyl-5-(3,5-diphenyl-1H-pyrazol-1-yl)pyrimidines 4 a-e by reaction of 1-(1-dimethylaminomethylene-2-oxo-2-phenylethyl)-3,5-diphenyl-1H-pyrazol e with acetamidine, benzamidine, guanidine, guanidinaecetic acid and creatine, respectively, is described. The alpha-aminoacid derivatives 4 d and 4 e gave a series of amides 7 by coupling with primary or secondary amines in dimethylformamide (DMF) solution in the presence of diphenyl-phosphorylazide (DPPA) and triethylamine. Some compounds 4 and 7 showed a platelet antiaggregating activity in vitro superior or comparable to that of acetyl-salicylic acid, as well as moderate antihypertensive, local anesthetic, analgesic and antiinflammatory activities in rats and mice.

Anesthetics, Local↗

PubMed1992

Soluble interleukin 2 receptors in polymyalgia rheumatica/giant cell arteritis. Clinical and laboratory correlations.

Serum levels of soluble interleukin 2 receptors (sIL-2R) were measured in 21 patients with polymyalgia rheumatica (PMR)/giant cell arteritis (GCA) prior to steroid treatment. These levels were significantly elevated in patients with PMR/GCA compared with healthy controls (p = 0.002). A significantly longer duration of morning stiffness (p = 0.005) was observed in patients with a high concentration of sIL-2R. A significant correlation was observed at diagnosis between sIL-2R and erythrocyte sedimentation rate (ESR) (p = 0.01) and between ESR and C-reactive protein (CRP) (p = 0.005). We investigated prospectively a group of 10 patients over a period of 6 months of prednisone therapy. At the end of the study sIL-2R levels fell significantly compared to pretreatment values (p = 0.02), but remained significantly higher compared to controls (p = 0.02). ESR and CRP values also fell significantly compared to pretreatment levels (p = 0.0001 in both cases). We observed a significant correlation between the decrease in ESR values and the decrease in sIL-2R and CRP levels after 6 weeks (p = 0.01 in both cases) and after 6 months of therapy (p = 0.002 and p = 0.05). sIL-2R may be considered a useful serologic marker for monitoring response to steroid therapy in patients with PMR/GCA. This laboratory variable correlated more closely with ESR than with CRP. The presence of elevated levels of sIL-2R is likely to reflect T cell activation occurring in PMR/GCA. T lymphocyte activation persisted after 6 months of steroid therapy, despite rapid and continuous control of disease manifestations.

Aged↗

PubMed1992

Low dose cyclosporine A in psoriatic arthritis: relation between soluble interleukin 2 receptors and response to therapy.

Twelve patients with psoriatic arthritis (PsA) were treated with low doses of cyclosporine A (CsA) (the initial dose was 3 mg/kg daily) and were entered into an open 6-month study. At the end of the study arthritis was improved in 7 patients (number of patients achieving a 50% or more reduction in the number of swollen or tender joints) and unchanged in 4 patients. Cutaneous psoriasis also improved significantly as shown by psoriasis area and severity index score. Only one patient withdrew from the study after one month because of severe nephrotoxicity. Serum creatinine fell to baseline value 6 weeks after the discontinuation of CsA. Three patients had minor side effects. CsA maintained articular improvement also in the 9 patients who are still taking this drug (mean duration of therapy of 12 +/- 0.8 months). There was no significant reduction of erythrocyte sedimentation rate during the study period. We assayed levels of soluble interleukin 2 receptors (sIL-2R) in serial serum samples obtained from 10 patients during the study period. Concentrations of sIL-2R were significantly increased in patients with PsA compared to controls. In 6 responder patients we observed a parallel decrease in joint pain/tenderness score and serum sIL-2R values. This finding was not observed in 4 nonresponders. Our results suggest that low dose CsA is a short term effective and safe therapy in patients with PsA and that serial sIL-2R levels are a useful means of measuring changes in disease activity.

Arthritis, Psoriatic↗