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Biomedical subjects

G Falcone

Publications and source records attributed to G Falcone.

At least 19 recordsLinked to original sources
PubMed2001

Synthesis of new N,N-disubstituted 4-amino-5,6-dihydro-3-phenyl-2H-thieno[2,3-h]-1-benzopyran-2-ones.

The synthesis of some N,N-disubstituted 4-amino-5,6-dihydro-3-phenyl-2H-thieno[2,3-h]-1-benzopyran-2-ones (4a-f), by reaction of phenylchloroketene with a series of N,N-disubstituted (E)-5-aminomethylene-6,7-dihydrobenzo[b]thiophen-4(5)-ones, followed by dehydrochlorination in situ of the primary adducts with DBN, is described. A moderate local anaesthetic activity was observed in the title compounds, particularly in 4e.

Analgesia↗
PubMed2001

N-Acyl-N-phenyl ureas of piperidine and substituted piperidines endowed with anti-inflammatory and anti-proliferative activities.

Six series of N-acyl-N-phenyl ureas 1-6 of piperidine (1), and 2-ethyl- (2), 3-methyl- (3), 4-methyl- (4), 4-phenyl- (5), cis-2,6-dimethyl- (6) piperidine were synthesised and evaluated for their anti-inflammatory, anaesthetic, anti-pyretic properties. Some derivatives of series 1 and 5 were also assayed for anti-proliferative activity. Several compounds showed an anti-inflammatory activity comparable or slighty inferior to that of indomethacin in rats (1c,d, 2a,b,g,h, 3b, 4h, 5d,e). Moreover, an appreciable anti-inflammatory activity was also found in 2c,e, 3e,f,g, 4g, 5a,b,c,f,h, and 6a,b,d. All the compounds were devoid of anti-pyretic activity and only a few of them exhibited a low level of infiltration anaesthesia in mice. Compound 5a showed a broad spectrum anti-cancer activity (at low micromolar concentrations), particulary significant against leukemia subpanel.

Analgesia↗
PubMed2001

3-Arylsulphonyl-5-arylamino-1,3,4-thiadiazol-2(3H)ones as anti-inflammatory and analgesic agents.

Two series of 3-arylsulphonyl-5-arylamino-1,3,4-thiadiazol-2(3H)ones 2 with potential anti-inflammatory and analgesic activity were prepared and tested. Pharmacological results revealed that all the title compounds, endowed with an arylsulphonyl side chain, possess good antalgic activity and fair anti-inflammatory properties. The analgesic profile of the two series, evaluated by the acetic acid writhing test, showed that compounds 2c, 2f and 2h, in particular, were the most active. Structure-activity relationships are briefly discussed.

Analgesics↗
PubMed2000

Anti-inflammatory and analgesic amides: new developments.

A series of substituted N-cycloalkyl benzamides, cinnamamides, and indole-3-carboxamides were synthesized and evaluated for their analgesic, antiinflammatory activities as well as for their gastrointestinal irritation liability. Indomethacin was used as reference drug in both tests. Compounds 1k, 1b, 1h, 1j, and 1g were the most active in the antiinflammatory paw edema inhibition test, with a sharply dose-dependent effect. In terms of the analgesic activity (acetic acid writhing test), the most active compound was 5a followed by 3a, but many other compounds were found to have a non-negligible potency. Even in this case, the effect was dose dependent.

Amides↗
PubMed2000

Synthesis and preliminary biological evaluation of novel N-substituted 1-amino-3-[1-methyl(phenyl)-1H-indazol-4-yloxy]-propan-2-ols interesting as potential antiarrhythmic, local anaesthetic and analgesic agents.

A series of indazoloxypropanolamines 7 and 8, pindolol isosteres, were synthesized to extend the structure activity relationship (SAR) which was observed in an earlier series of related derivatives. Compounds 7, characterized by methyl substitution on the N-1 indazole nucleus, generally exhibited significant antiarrhythmic, local anaesthetic and analgesic activities. The preliminary radioligand binding assay highlighted, in compounds 7, an interesting beta 1-affinity which can be well correlated to their antiarrhyhtmic activity. Analogues 8 characterized by a phenyl group on the N-1 indazole nucleus, were generally less active as antiarrhyhtmic agents but generally interesting as local anaesthetics. Due to the importance of the indazole moiety as a carrier of antiphlogistic activity, the two classes of derivatives 7 and 8 were evaluated for their NSAID behaviour. Once again, compounds 7 resulted having more interesting analgesic and antipyretic effects than analogues 8.

Analgesics, Non-Narcotic↗
PubMed2000

Characterization of clinical tolerance to inhaled zinc oxide in naive subjects and sheet metal workers.

Clinical tolerance to the acute effects of zinc oxide inhalation develops in workers during periods of repeated exposure. The aims of this study were to determine whether clinical tolerance is accompanied by a reduction in the acute pulmonary inflammatory and cytokine responses to zinc oxide exposure and whether tolerance can be demonstrated in sheet metal workers who chronically inhale low levels of zinc oxide. Naive (never-exposed) subjects inhaled 5 mg/m3 zinc oxide on 1 or 3 days and underwent bronchoalveolar lavage 20 hours after the final exposure. Sheet metal workers inhaled zinc oxide on 1 day and control furnace gas on another day. Among naive subjects in whom tolerance was induced, bronchoalveolar lavage fluid percent neutrophils and interleukin-6 (IL-6) levels were significantly decreased compared with subjects who underwent only a single exposure. Sheet metal workers were much less symptomatic, but they still experienced a significant increase in plasma IL-6. The results indicate that clinical tolerance to zinc oxide is accompanied by reduced pulmonary inflammation and that chronically exposed sheet metal workers are not clinically affected by exposure to zinc oxide fume at the Occupational Safety and Health Administration Permissible Exposure Limit. The increase in IL-6 levels observed in the clinically responsive, and to a lesser extent, tolerant, states following zinc oxide inhalation is consistent with the dual role of IL-6 as a pyrogen and anti-inflammatory agent.

Administration, Inhalation↗
PubMed2000

Antibiotic drug prescription in respiratory tract infections: a pharmacoepidemiological survey among general practitioners in a region of Italy.

Data concerning patients undergoing antibiotic treatment for upper (URTI) or lower (LRTI) respiratory tract infections were collected from 23 General Practitioners (GPs) in the Campania Region of Italy from November 15, 1997 to March 15, 1998. The objectives of the study were: a) to assess the occurrence of URTIs and LRTIs; b) to document the factors that influence GPs' choice of therapy; c) to correlate antibiotic choice with duration and outcome of treatment; d) to assess the incidence of unwanted effects. 2198 questionnaires were collected. Patients were +/-43.9 of age. URTIs were diagnosed in 65.4% and 34.6% LRTIs. The mean duration of antibiotic treatment was 4.5 days in URTIs and 5.6 days in LRTIs. The choice of antibiotic treatment was influenced by clinical assessment of infections (67.1%). The most commonly used antibiotic categories in URTIs were macrolides (39.3%), penicillins (27.4%) and cephalosporins (23.8%) whereas for LRTIs mainly cephalosporins (63.8%), penicillins (9.2%) and fluoroquinolones (7.4%) were used. Adverse events were experienced by 3.9% of patients.

Adolescent↗
PubMed2000

Synthesis of substituted N-(4-piperidyl)-N-(3-pyridyl)amides with antiarrhythmic activity. Note 1.

The synthesis of analogues of N,2-diphenyl-N-(4-piperidyl)acetamide endowed with antiarrhythmic activity is reported. Benzoyl, cinnamoyl, acetyl and propionyl groups replace the phenacyl group as N-acyl substituent, while pyridine replaces benzene as aromatic ring bound to the amide nitrogen. The title compounds were evaluated for antiarrhythmic activity on experimental arrhythmias induced by aconitine in rats. The presence of a n-propyl chain and an unsubstituted cinnamoyl moiety (1j) gives the highest protection against aconitine induced extrasystoles while the best efficacy against lethal effects is due to the presence of a n-propyl chain and an acetyl moiety (1m).

Aconitine↗
PubMed1999

Synthesis and biological evaluation of [alpha-(1,5-disubstituted 1H-pyrazol-4-yl)benzyl]azoles, analogues of bifonazole.

A series of pyrazole analogues of bifonazole, an antifungal drug used in clinical practice, 2a-h and 4a-h were synthesized and tested in vitro against Candida albicans, Cryptococcus neoformans and Aspergillus fumigatus, with no significant results. Imidazoles 2a-h were also tested in vivo for antiarrhythmic and antihypertensive activities; two of these compounds showed moderate activity against ventricular fibrillation caused by aconitine in rats. The above compounds were prepared by reaction of phenyl-[5 substituted 1-phenyl (or 1-methyl)-1H-pyrazol-4-yl]methanols with N,N'-carbonyldiimidazole (2a-h) or of the respective chloro derivatives with 1H-1,2,4-triazole (4a-h).

Animals↗
PubMed1999

Induction of telomerase activity in v-myc-transformed avian cells.

Telomerase activity is detectable in the majority of tumors or immortalized cell lines, but is repressed in most normal human somatic cells. It is generally assumed that reactivation of telomerase prevents the erosion of chromosome ends which occurs in cycling cells and, hence, hinders cellular replicative senescence. Here, we show that the expression of v-Myc oncoprotein by retroviral infection of telomerase-negative embryonal quail myoblasts and chicken neuroretina cells is sufficient for reactivating telomerase activity, earlier than telomere shortening could occur. Furthermore, the use of a conditional v-Myc-estrogen receptor protein (v-MycER) causes estrogen-dependent expression of detectable levels of telomerase activity in recently infected chick embryo fibroblasts and neuroretina cells. We conclude that the high levels of telomerase activity in v-Myc-expressing avian cells are not the mere consequence of transformation or of a differentiative block, since v-Src tyrosine kinase, which prevents terminal differentiation and promotes cell transformation, fails to induce telomerase activity.

Animals↗
PubMed1999

Distinct effects of Rac1 on differentiation of primary avian myoblasts.

Rho family GTPases have been implicated in the regulation of the actin cytoskeleton in response to extracellular cues and in the transduction of signals from the membrane to the nucleus. Their role in development and cell differentiation, however, is little understood. Here we show that the transient expression of constitutively active Rac1 and Cdc42 in unestablished avian myoblasts is sufficient to cause inhibition of myogenin expression and block of the transition to the myocyte compartment, whereas activated RhoA affects myogenic differentiation only marginally. Activation of c-Jun N-terminal kinase (JNK) appears not to be essential for block of differentiation because, although Rac1 and Cdc42 GTPases modestly activate JNK in quail myoblasts, a Rac1 mutant defective for JNK activation can still inhibit myogenic differentiation. Stable expression of active Rac1, attained by infection with a recombinant retrovirus, is permissive for terminal differentiation, but the resulting myotubes accumulate severely reduced levels of muscle-specific proteins. This inhibition is the consequence of posttranscriptional events and suggests the presence of a novel level of regulation of myogenesis. We also show that myotubes expressing constitutively active Rac1 fail to assemble ordered sarcomeres. Conversely, a dominant-negative Rac1 variant accelerates sarcomere maturation and inhibits v-Src-induced selective disassembly of I-Z-I complexes. Collectively, our findings provide a role for Rac1 during skeletal muscle differentiation and strongly suggest that Rac1 is required downstream of v-Src in the signaling pathways responsible for the dismantling of tissue-specific supramolecular structures.

Animals↗
PubMed1998

Eps8, a tyrosine kinase substrate, is recruited to the cell cortex and dynamic F-actin upon cytoskeleton remodeling.

Eps8 is a recently identified substrate of receptor and nonreceptor tyrosine kinases implicated in the control of cell proliferation. To investigate potential functions of Eps8, its intracellular localization has been examined in several cell types. In cycling fibroblasts immunolabeling with antibodies to Eps8 reveals a punctate pattern within the perinuclear region and staining of motile peripheral cell extensions and cell-cell contact regions. Stimulation of quiescent Swiss 3T3 fibroblasts with serum induces a striking reorganization of the actin cytoskeleton which is accompanied by the enrichment of Eps8 and cortactin in membrane ruffles and lamellipodia. A similar accumulation of Eps8 to membrane ruffles is observed in cells treated with phorbol esters, which also induce marked changes of the F-actin cytoskeleton. The localization of Eps8 at the cell cortex is largely independent from the binding of Eps8 to an EGFR/ErbB-2 chimeric receptor. Moreover, fractionation studies reveal that a portion of the Eps8 molecules present in the cell periphery, unlike cortactin and the receptor, is resistant to mild extraction with detergent. Upon cellular transformation by the tyrosine kinase v-Src, a pool of Eps8 is recruited to newly formed specialized regions of the cytoskeleton, such as actin bodies in terminally differentiated myotubes and podosomes in fibroblasts, where cortactin and a variety of cytoskeletal proteins are also found. Extraction with Triton X-100 preserves the association of Eps8 to podosomes and leaves the majority of the v-Src tyrosine-phosphorylated Eps8 in the detergent-resistant fraction. The observed recruitment of Eps8 to highly dynamic cytoskeletal structures of normal and transformed cells suggests that Eps8 may play a role in the reorganization of the cytoskeleton, perhaps acting as a docking site for other signaling molecules.

3T3 Cells↗
PubMed1998

Research on heterocyclic compounds, Part 40. 2-Phenylimidazo[1,2-a]pyridine-3-carboxylic acid derivatives: synthesis and antiinflammatory activity.

A series of 2-phenylimidazo[1,2-a]pyridine-3-carboxylic esters, acids, and amides were synthesized and pharmacologically tested in order to evaluate their antiinflammatory and analgesic activity and their ulcerogenic action on the gastro-intestinal tract. The most active member of this series of compounds was found to be 6-methyl-2-phenylimidazo[1,2-a]pyridine-3-carboxylic acid (5c).

Animals↗
PubMed1998

Synthesis of 1-methyl-4-(N-aroyl)-piperidinamides with anti-inflammatory and analgesic activities.

Two series of 1-methyl-4-(N-aroyl)-piperidinamides were synthesized and evaluated for their anti-inflammatory and analgesic properties, as well as for their gastrointestinal irritation liability. A non-aromatic derivative, 1-methyl-4-(N-cyclohexanoyl)-piperidinamide, was synthesized and evaluated in order to obtain a more exhaustive knowledge of the structure-activity relationship.

Amides↗
PubMed1998

Cardiotoxicity of doxorubicin: effects of 21-aminosteroids.

The purposes of this study were to investigate in vivo the effects of two lazaroids,U-74389G (21-[4-(2,6-di-1-pyrrolidinyl-4-pyrimidinyl)-1-piperazinyl]-pregna-1,4,9 (11)-triene-3,20-dione (2)-2-butenenedionate) and U-83836E (-)-2-[[4-(2,6-di-1-pyrrlidinyl-4-pyrimidinyl)-1-piperazinyl]methy l]-3,4-dihydro-2,5,7,8-tetramethyl-2H-1-benzopyran-6-ol, dihydrochloride against the cardiotoxicity induced by doxorubicin in rat and the mechanisms underlying such a toxicity. Doxorubicin (DXR) administered intraperitoneally (5 mg/kg 4 times per week for 1 week) induced significant decrease of body weight, ECG alterations and 100% mortality. The lazaroids used in this study did not protect from DXR-induced cardiotoxicity. Our results showed that the compound U-74389G delayed, but did not reduce DXR-induced mortality, and did not prevent body weight loss and ECG changes. The compound U-83836E was unable to modify any toxic effects induced by DXR. These data indicate that oxygen free radicals and the subsequent increase in intracellular calcium are only steps of DXR progressive general toxicity that leads to cardiac injury. In conclusion, we propose that the 21-aminosteroids, potent inhibitors of membrane lipid peroxidation, alone are not enough to protect from DXR toxic effects.

Animals↗