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1.
Ann Ig ; 35(5): 572-585, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37082931

RESUMO

Introduction: The COVID-19 pandemic has had a major impact on the Healthcare System, changing the patterns of Emergency Department access. In fact, accesses for trauma and less severe cases decreased significantly. This decline has generally been attributed to both the effects of the lockdown, imposed by the government, and the fear of being infected by SARS-CoV-2 in the hospital. However, the correlation between these elements is not yet clear, since the accesses to the Emergency Department did not increase either at the end of the lockdown or in the summer when the epidemiological situation was more favorable. Aim: To evaluate the association between trends of Emergency Department accesses and COVID-19 incidence in 2020. Methods: Data on Emergency Department accesses, by month and severity triage code, from 14 hospitals in southeastern Tuscany (Italy) were obtained from hospitals' data warehouse. Official data on new cases of COVID-19 infection were used to calculate incidence. Hospitals were classified into 4 categories. Differences in Emergency Department access by month, triage code, and hospital type were investigated using Kruskal-Wallis analysis. Association between Emergency Department accesses and COVID-19 incidence was evaluated using a random-effect panel data analysis, adjusting for hospital type and triage code. Results: The trend of 268,072 Emergency Department accesses decreases substantially at the first pandemic peak; thereafter, it increased and decreased again until the minimum peak in November 2020. COVID-19 incidence appeared to be overlapping with an inverse direction. Monthly differences were significant (p<0.01) except for most severe codes. There was a significant inverse association between Emergency Department accesses and COVID-19 incidence (Coef. =-0.074, p<0.001) except for most severe cases (triage code 1: Coef. =-0.028, p=0.154). Conclusion: Emergency Department admissions trend followed the COVID-19 incidence, except for the most severe cases. Fear of infection seems to discourage patients from accessing Emergency Department for illnesses perceived as not serious.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , SARS-CoV-2 , Pandemias , Estudos Retrospectivos , Incidência , Controle de Doenças Transmissíveis , Serviço Hospitalar de Emergência , Itália/epidemiologia
4.
J Gambl Stud ; 37(3): 853-874, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33481142

RESUMO

Actual and perceptual measures of gambling exposure are important predictors of problem gambling. This study used Zero-Inflated Poisson regression analyses to assess the relative and interactive effects of actual and perceived exposure on problem gambling risk and severity. Data from the 2008 and 2009 Social and Economic Impacts of Gambling in Alberta surveys indicated actual exposure was significantly associated with problem gambling risk while perceived exposure was significantly associated with problem gambling severity. These associations differ for gamblers from emerging and mature areas. Further, actual and perceived exposure had significant interaction effects on problem gambling severity but not on risk. Implications from these findings suggest that the prevalence of problem gambling could be reduced by restrictions on gambling opportunities.


Assuntos
Jogo de Azar , Alberta/epidemiologia , Jogo de Azar/psicologia , Humanos , Prevalência , Inquéritos e Questionários
5.
J Gambl Stud ; 37(4): 1291-1310, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33247819

RESUMO

Measures of availability and accessibility are often used separately or interchangeably to assess gambling exposure. This study examined the advantages of assessing gambling exposure using availability, accessibility, and a composite measure. Logistic and poisson regression analyses were used to determine the relative importance of these measures in predicting problem gambling using data from the 2008 and 2009 Social and Economic Impacts of Gambling in Alberta (SEIGA) surveys. The composite measure of gambling exposure predicted both the risk and severity of problem gambling better than the availability or accessibility measures alone. These results demonstrate that individual differences in problem gambling are better predicted by a composite measure of exposure.


Assuntos
Jogo de Azar , Alberta/epidemiologia , Jogo de Azar/psicologia , Humanos , Análise de Regressão
7.
J Prev Med Hyg ; 59(1): E88-E91, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29938243

RESUMO

INTRODUCTION: A lot of drug groups are associated with preventable drug-related admissions. Coumarin derivatives, prescribed for the treatment and prevention of deep vein thrombosis or pulmonary embolism or prevention of systemic embolism or stroke in patients with prosthetic heart valves or atrial fibrillation, are often associated with bleeding. The aim of our study was to analyze how the anticoagulant therapy with VKAs could affects the hospitalizations and the visits to emergency room in the elderly population (> 65 years old). METHODS: In 2013 we conducted a cross sectional study analyzing the database of all pharmaceutical prescriptions, selecting patients living in Grosseto (Italy), which received at least two prescriptions of coumarin derivatives in 2012. We analyzed the admissions to hospital and the accesses to the emergency rooms (ERs) made by each patient, focusing especially on those related to bleeding. For each access to ER we recorded the date, time of stay, diagnosis and outcome. For each hospitalization the information we recorded were the date of admission and discharge diagnosis. RESULTS: 3684 patients were included in our study. 261 (7.1%) patients visited the emergency room for bleeding; 37 (1%) for intracranial bleeding. The accesses made by men were higher than those made by women. The average time of stay in ER was 349 minutes. The admissions to hospital were 96 (2.6%); 42 (1.1%) were admitted to hospital with a diagnosis of major vascular event. 53 patients (20.3%), accessed to the ER more than one time. The 11.5% was admitted to the hospital more than one time. CONCLUSIONS: Our study showed that VKAs are responsible of an increase of the accesses to ER and of the admissions to hospital. However, it would be interesting to enlarge the sample size including patients living in other provinces or in other regions, with a lower age and treated also with TSOACs, in order to evaluate the real cost-effectiveness of anticoagulant therapy.


Assuntos
Anticoagulantes/uso terapêutico , Serviço Hospitalar de Emergência , Hospitalização , Vitamina K/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Bases de Dados Factuais , Feminino , Humanos , Itália , Masculino , Resultado do Tratamento
9.
Naunyn Schmiedebergs Arch Pharmacol ; 389(9): 1033-43, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27351883

RESUMO

Asymmetrical N,N-bis(alkanol)amine aryl esters (FRA77, GDE6, and GDE19) are potent multidrug resistance (MDR) reversers. Their structures loosely remind that of the Ca(2+) antagonist verapamil. Therefore, the aim of this study was to investigate their vascular activity in vitro. Their effects on the mechanical activity of fresh and cultured rat aorta rings on Cav1.2 channel current (I Ca1.2) of A7r5 cells and their cytotoxicity on A7r5 and EA.hy926 cells were analyzed. Docking at the rat α1C subunit of the Cav1.2 channel was simulated in silico. Compounds tested were cytotoxic at concentrations >1 µM (FRA77, GDE6, GDE19) and >10 µM (verapamil) in EA.hy926 cells, or >10 µM (FRA77, GDE6, GDE19) and at 100 µM (verapamil) in A7r5 cells. In fresh rings, the three compounds partly antagonized phenylephrine and 60 mM K(+) (K60)-induced contraction at concentrations ≥1 and ≥3 µM, respectively. On the contrary, verapamil fully relaxed rings pre-contracted with both agents. In cultured rings, 10 µM GDE6, GDE19, FRA77, and verapamil significantly reduced the contractile response to both phenylephrine and K60. Similarly to verapamil, the three compounds docked at the α1C subunit, interacting with the same amino acids residues. FRA77, GDE6, and GDE19 inhibited I Ca1.2 with IC50 values 1 order of magnitude higher than that of verapamil. FRA77-, GDE6-, and GDE19-induced vascular effects occurred at concentrations that are at least 1 order of magnitude higher than those effectively reverting MDR. Though an unambiguous divergence between MDR reverting and vascular activity is of overwhelming importance, these findings consistently contribute to the design and synthesis of novel and potent chemosensitizers.


Assuntos
Aminas/farmacologia , Bloqueadores dos Canais de Cálcio/farmacologia , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Ésteres/farmacologia , Simulação de Acoplamento Molecular , Músculo Liso Vascular/efeitos dos fármacos , Miócitos de Músculo Liso/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos , Vasodilatadores/farmacologia , Aminas/química , Aminas/metabolismo , Animais , Sítios de Ligação , Bloqueadores dos Canais de Cálcio/metabolismo , Canais de Cálcio Tipo L/química , Canais de Cálcio Tipo L/efeitos dos fármacos , Canais de Cálcio Tipo L/metabolismo , Linhagem Celular , Relação Dose-Resposta a Droga , Células Endoteliais/metabolismo , Ésteres/química , Ésteres/metabolismo , Humanos , Masculino , Potenciais da Membrana , Estrutura Molecular , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Ligação Proteica , Ratos , Ratos Wistar , Relação Estrutura-Atividade , Técnicas de Cultura de Tecidos , Vasodilatadores/química , Vasodilatadores/metabolismo , Verapamil/metabolismo , Verapamil/farmacologia
10.
Eur J Med Chem ; 66: 56-68, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23792316

RESUMO

A series of new histone deacetylase inhibitors were designed and synthesized based on hybridization between SAHA or oxamflatin and 5-phenyl-1,4-benzodiazepines. The compounds were tested for their enzyme inhibitory activity on HeLa nuclear extracts, and on human recombinant HDAC1 and HDAC6. Antiproliferative activity was tested on different cancer cells types, while proapoptotic activity was primarily tested on NB4 cells. The compounds showed IC50 values similar to those of SAHA. Compound (S)-8 displayed interesting activity against hematological and solid malignancies.


Assuntos
Benzodiazepinas/síntese química , Benzodiazepinas/farmacologia , Desenho de Fármacos , Inibidores de Histona Desacetilases/síntese química , Inibidores de Histona Desacetilases/farmacologia , Histona Desacetilases/metabolismo , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Benzodiazepinas/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Técnicas de Química Sintética , Inibidores de Histona Desacetilases/química , Humanos , Solubilidade , Estereoisomerismo , Relação Estrutura-Atividade
11.
Bioorg Med Chem Lett ; 22(5): 1936-9, 2012 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-22325944

RESUMO

A series of analogs of DM235 and MN19, characterized by rings with different size, have been prepared and evaluated for their nootropic activity in the mouse passive-avoidance test. It was found that the optimal ring size for the analogs of DM235, showing endocyclic both amidic groups, is 6 or 7 atoms. For the compounds structurally related to MN19, carrying an exocyclic amide group, the piperidine ring is the moiety which gives the most interesting compounds.


Assuntos
Cognição/efeitos dos fármacos , Nootrópicos/química , Nootrópicos/farmacologia , Piperazinas/química , Piperazinas/farmacologia , Sulfonamidas/química , Sulfonamidas/farmacologia , Adjuvantes Anestésicos , Amnésia/induzido quimicamente , Amnésia/tratamento farmacológico , Animais , Aprendizagem da Esquiva/efeitos dos fármacos , Desenho de Fármacos , Camundongos , Nootrópicos/uso terapêutico , Piperazinas/uso terapêutico , Escopolamina , Relação Estrutura-Atividade , Sulfonamidas/uso terapêutico
12.
Curr Top Med Chem ; 10(17): 1715-31, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20645921

RESUMO

Multidrug resistance (MDR) is a kind of acquired resistance of microorganisms and cancer cells to chemotherapeutic drugs that are characterized by different chemical structure and different mechanism of action. Classic MDR is due to a lower intracellular concentration of cytotoxic drugs that is associated with accelerated efflux of the chemotherapeutic drugs and is the consequence of the over expression of transporter proteins that act as extrusion pumps. P-glycoprotein (P-gp/ABCB1) is the most important and studied member of such proteins belonging to the ATP Binding Cassette (ABC) superfamily of transporters that use ATP as energy source. Inhibition of the functions of P-gp and other ABC proteins could represent a way to circumvent appearance of MDR in cancer cells and the most classical pharmacological strategy is the administration of agents able to modulate the P-gp function. On the basis of the known characteristics of the recognition site of P-gp, we have designed a new class of P-gp-mediated MDR reverters. These compounds are flexible molecules carrying a basic nitrogen atom flanked, at properly modulated distance, by two aromatic moieties; most of them possess MDR inhibitory activity on anthracycline-resistant erytroleukemia K562 cells. By applying the frozen analog approach to that series of very flexible MDR reverters, we identified a new series of N,N-bis(cyclohexanol)amine aryl esters that show very interesting MDR-reversing properties. Among them, compound 15d, that consistently shows low nanomolar potency and high efficacy in all the tests used, appears as a new pharmacological tool for P-gp studies and a promising lead for the development of potent, efficient and safe MDR reverters.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Transportadores de Cassetes de Ligação de ATP/antagonistas & inibidores , Antineoplásicos/farmacologia , Cicloexilaminas/farmacologia , Descoberta de Drogas , Animais , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Cicloexilaminas/química , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Humanos
13.
Curr Drug Targets ; 7(7): 893-909, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16842220

RESUMO

Multidrug resistance (MDR) is a kind of acquired resistance of microorganisms and cancer cells to chemotherapic drugs that are characterized by different chemical structure and different mechanism of action. Classic MDR is the consequence of the over-expression of a variety of proteins that extrude the chemotherapic from the cell, lowering its concentration below the effective one. The ABC (ATP Binding Cassette) is a ubiquitous and important family of such transporter proteins. Members of this super family are present in mammals as well as in prokaryotic organisms and use ATP as the energy source to activate the extrusion process. P-glycoprotein (Pgp) and Multidrug Resistance Proteins (MRP1 and sister proteins) are the most important and widely studied members of ABC super family. Our knowledge about the structures and functions of transporter proteins has definitely improved in recent years, following the resolution of the structure of bacterial pumps which opened the way to the building of homology models for the more complex Pgp and MRP. It can be anticipated that these results will have a strong impact on the design of more potent and safer MDR reverters. A huge number of small molecules, many of natural origin, are able to reverse multidrug resistance by inhibiting the functions of Pgp, MRP1 and sister proteins and their action has been considered a possible way to reverse MDR. However, while a few compounds have reached clinical trials, none of them has, so far, been cleared for therapeutic use. Two main reasons are at the base of this difficulty: i) MDR is a complex phenomenon that may arise from several different biochemical mechanisms, with the consequence that inhibition of transporter proteins may be insufficient to reverse it; ii) the physiological role of Pgp and sister proteins requires more potent modulators with proper selectivity and pharmacokinetic in order to avoid unwanted side effects. This paper first reviews the most recent discoveries on the structures and functions of the ABC super family, in particular Pgp and MRP. Then, the medicinal chemistry of MDR reverters, in light of these findings, is discussed and the molecules that are presently in development are reviewed.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Transportadores de Cassetes de Ligação de ATP/fisiologia , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Moduladores de Transporte de Membrana/uso terapêutico , Proteínas Associadas à Resistência a Múltiplos Medicamentos/antagonistas & inibidores , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/química , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/fisiologia , Transportadores de Cassetes de Ligação de ATP/antagonistas & inibidores , Transportadores de Cassetes de Ligação de ATP/química , Ensaios Clínicos como Assunto , Desenho de Fármacos , Resistência a Múltiplos Medicamentos/fisiologia , Humanos , Moduladores de Transporte de Membrana/química , Moduladores de Transporte de Membrana/farmacologia , Modelos Moleculares , Estrutura Molecular , Proteínas Associadas à Resistência a Múltiplos Medicamentos/química , Proteínas Associadas à Resistência a Múltiplos Medicamentos/fisiologia
14.
Farmaco ; 57(5): 385-415, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12058813

RESUMO

Multidrug resistance (MDR) is a kind of resistance of cancer cells to multiple classes of chemotherapic drugs that can be structurally and mechanistically unrelated. Classical MDR regards altered membrane transport that results in lower cell concentrations of cytotoxic drug and is related to the over expression of a variety of proteins that act as ATP-dependent extrusion pumps. P-glycoprotein (Pgp) and multidrug resistance protein (MRP1) are the most important and widely studied members of the family that belongs to the ABC superfamily of transporters. It is apparent that, besides their role in cancer cell resistance, these proteins have multiple physiological functions as well, since they are expressed also in many important non-tumoural tissues and are largely present in prokaryotic organisms. A number of drugs have been identified which are able to reverse the effects of Pgp, MRPI and sister proteins, on multidrug resistance. The first MDR modulators discovered and studied in clinical trials were endowed with definite pharmacological actions so that the doses required to overcome MDR were associated with unacceptably high side effects. As a consequence, much attention has been focused on developing more potent and selective modulators with proper potency, selectivity and pharmacokinetics that can be used at lower doses. Several novel MDR reversing agents (also known as chemosensitisers) are currently undergoing clinical evaluation for the treatment of resistant tumours. This review is concerned with the medicinal chemistry of MDR reversers, with particular attention to the drugs that are presently in development.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/fisiologia , Resistência a Múltiplos Medicamentos , Proteínas Associadas à Resistência a Múltiplos Medicamentos/fisiologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/química , Animais , Resistencia a Medicamentos Antineoplásicos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Proteínas Associadas à Resistência a Múltiplos Medicamentos/química , Relação Estrutura-Atividade , Células Tumorais Cultivadas
15.
Nucl Med Commun ; 23(1): 5-11, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11748432

RESUMO

The purpose of this prospective study was to detect symptomatic cerebral vasospasm in aneurysmal subarachnoid haemorrhage (SAH) by a non-invasive mean cerebral blood flow (mCBF) quantification using 99mTc-ethyl cysteinate dimer. Measurement of mCBF without blood sampling and single photon emission tomography (SPECT) were performed at 1 and 7 days after surgery in 35 consecutive SAH patients, of whom 16 were examined at day 30 as well. A decrease in mCBF of more than 10% on day 7 versus day 1 was considered to indicate vasospasm. On visual interpretation of SPECT, a perfusion decrease which appeared newly on day 7 was considered to indicate vasospasm. In total, nine of 35 patients had cerebral vasospasm confirmed by computed tomography (CT) and/or angiography. The mCBF measurement showed a 77.8% (7/9) sensitivity, a 88.5% (23/26) specificity, a 70.0% (7/10) positive predictive value, and a 92.0% (23/25) negative predictive value. SPECT yielded a 33.3% (3/9) sensitivity, a 73.1% (19/26) specificity, a 30.0% (3/10) positive predictive value, and a 76.0% (19/25) negative predictive value. On SPECT, decreased perfusion was observed in most of the patients at clipping sites, which might represent post-operative transient abnormal perfusion and should not be read as vasospasm. In conclusion, this mCBF measurement is more accurate than visual interpretation of SPECT for detecting vasospasm.


Assuntos
Circulação Cerebrovascular/fisiologia , Cisteína/análogos & derivados , Aneurisma Intracraniano/diagnóstico por imagem , Compostos de Organotecnécio , Compostos Radiofarmacêuticos , Hemorragia Subaracnóidea/diagnóstico por imagem , Adulto , Angiografia Cerebral , Feminino , Humanos , Aneurisma Intracraniano/complicações , Aneurisma Intracraniano/fisiopatologia , Masculino , Pessoa de Meia-Idade , Hemorragia Subaracnóidea/complicações , Hemorragia Subaracnóidea/fisiopatologia , Tomografia Computadorizada de Emissão de Fóton Único , Tomografia Computadorizada por Raios X , Vasoespasmo Intracraniano/diagnóstico por imagem , Vasoespasmo Intracraniano/etiologia
16.
J Med Chem ; 44(23): 3946-55, 2001 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-11689081

RESUMO

DMPP is a well-known nicotinic agonist that does not fit any proposed pharmacophore for nicotinic binding and represents a unique ligand among the hundreds of nicotinic agonists studied in the past decades. A systematic modulation of the chemical structure of DMPP, aimed to establish its structure-affinity relationships, is reported. The research has allowed to identify molecules such as 11c, 13c, 14c, and 28c, with affinities for alpha(4)beta(2) receptors in the low nanomolar range, some 2 orders of magnitude lower than the lead compound. The agonistic properties of the most interesting compounds have been assessed by measuring their analgesic activity on mice (hot-plate test). Another result of the research was the identification of DMPP analogues, such as 3a (K(i) = 90 nM) and 14b (K(i) = 180 nM), that maintain affinity for the central nicotinic receptor when the ammonium function is changed into an aminic one and are therefore possible leads for drug development in neurodegenerative diseases.


Assuntos
Iodeto de Dimetilfenilpiperazina/análogos & derivados , Iodeto de Dimetilfenilpiperazina/síntese química , Agonistas Nicotínicos/síntese química , Piperidinas/síntese química , Piridinas/síntese química , Receptores Nicotínicos/metabolismo , Analgésicos/síntese química , Analgésicos/química , Analgésicos/farmacologia , Animais , Córtex Cerebral/metabolismo , Iodeto de Dimetilfenilpiperazina/química , Iodeto de Dimetilfenilpiperazina/farmacologia , Técnicas In Vitro , Ligantes , Masculino , Camundongos , Agonistas Nicotínicos/química , Agonistas Nicotínicos/farmacologia , Medição da Dor , Piperidinas/química , Piperidinas/farmacologia , Piridinas/química , Piridinas/farmacologia , Ensaio Radioligante , Ratos , Ratos Wistar , Relação Estrutura-Atividade
17.
Bioorg Med Chem ; 9(10): 2673-82, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11557355

RESUMO

Several ring-substituted derivatives of previously studied MDR inhibitors 2-(3,4-dimethoxyphenyl)-5-(9-fluorenylamino)-2-(methylethyl)pentanenitrile and 2-(3,4-dimethoxyphenyl)-5-[(9-fluorenyl)-N-methylamino]-2-(methylethyl)pentanenitrile have been synthesised and studied with the aim of optimising activity and selectivity. The results show that MDR inhibition is scarcely sensitive to modulation of the electronic properties of the fluorene ring. Even if dramatic improvement was not obtained, one of the compounds (2) showed improved potency and selectivity with respect to the leads and appears to be a better candidate for drug development.


Assuntos
Resistência a Múltiplos Medicamentos , Fluorenos/química , Nitrilas/química , Animais , Antraciclinas/farmacologia , Aorta/efeitos dos fármacos , Cromatografia em Gel , Doxorrubicina/análogos & derivados , Doxorrubicina/farmacologia , Fluorenos/farmacologia , Cobaias , Frequência Cardíaca/efeitos dos fármacos , Humanos , Espectroscopia de Ressonância Magnética , Metilação , Modelos Químicos , Estrutura Molecular , Contração Miocárdica/efeitos dos fármacos , Nitrilas/farmacologia , Espectrometria de Fluorescência , Relação Estrutura-Atividade , Células Tumorais Cultivadas/efeitos dos fármacos , Vasodilatadores/química , Vasodilatadores/farmacologia
18.
Bioorg Med Chem ; 9(5): 1165-74, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11377175

RESUMO

As a continuation of previous research on anticholinergic drugs derived from 2,2-diphenyl-2-ethylthioacetic acid, several 5,5-diphenyl-5-ethylthio-2-pentynamines (2-11) were synthetised and their antimuscarinic activity on M(1-4) receptor subtypes was evaluated by functional tests and binding experiments. One of the compounds obtained showed unexpected agonistic activity in functional experiments on M(2) receptors. Since the compound carried a phenylpiperazine moiety, other similar compounds (12-17) were prepared and found to be endowed with similar behaviour. These ligands, although possessing the bulky structure characterising muscarinic antagonists, display agonistic activity at M(2) subtypes while, as expected, behaving as antagonists on M(3) and M(4) subtypes. On M(1) subtypes, they show agonistic activity which, however, is not blocked by atropine. The peculiar pharmacological profile of these compounds is of interest for studying muscarinic receptor subtypes.


Assuntos
Alcinos/farmacologia , Agonistas Muscarínicos/farmacologia , Antagonistas Muscarínicos/farmacologia , Receptores Muscarínicos/efeitos dos fármacos , Alcinos/síntese química , Animais , Atropina/farmacologia , Córtex Cerebral/metabolismo , Cobaias , Íleo/metabolismo , Técnicas In Vitro , Pulmão/metabolismo , Masculino , Miocárdio/metabolismo , Coelhos , Ratos , Receptor Muscarínico M1 , Receptor Muscarínico M2 , Receptor Muscarínico M3 , Relação Estrutura-Atividade , Suínos , Ducto Deferente/metabolismo
19.
J Med Chem ; 43(23): 4499-507, 2000 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-11087574

RESUMO

Several 4-substituted 1-acylpiperazines, obtained by molecular simplification of 4-substituted 1,4-diazabicyclo[4.3.0]nonan-9-ones, have been synthesized and tested in vivo on the mouse passive avoidance test, to evaluate their nootropic activity. The results show that, apparently, an N-acylpiperazine group can mimic the 2-pyrrolidinone ring of 1,4-diazabicyclo[4.3.0]nonan-9-one, as the compounds of the new series maintain high nootropic activity. Moreover molecular simplification produces more clear-cut structure-activity relationships with respect to the parent series. The mechanism of action also appears to be similar in the two series. In fact, although the molecular mechanism remains to be elucidated, the most potent compound of each class (DM232 and 13, DM235) is able to increase acetylcholine release in rat brain. Piperazine derivatives represent a new class of nootropic drugs with an in vivo pharmacological profile very similar to that of piracetam, showing much higher potency with respect to the reference compound. Among the compounds studied, 13 (DM235) shows outstanding potency, being active at a dose of 0.001 mg kg(-1) sc.


Assuntos
Compostos Bicíclicos Heterocíclicos com Pontes/química , Nootrópicos/síntese química , Piperazinas/síntese química , Acetilcolina/metabolismo , Analgésicos/síntese química , Analgésicos/química , Analgésicos/farmacologia , Animais , Aprendizagem da Esquiva/efeitos dos fármacos , Masculino , Memória/efeitos dos fármacos , Camundongos , Microdiálise , Nootrópicos/química , Nootrópicos/farmacologia , Lobo Parietal/metabolismo , Piperazinas/química , Piperazinas/farmacologia , Ratos , Ratos Wistar , Comportamento Social , Relação Estrutura-Atividade
20.
J Med Chem ; 43(10): 1969-74, 2000 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-10821709

RESUMO

Several 4-substituted 1,4-diazabicyclo[4.3.0]nonan-9-ones have been synthesized and tested in vivo on mouse passive avoidance test, to evaluate their nootropic activity. The results show that they represent a new class of nootropic drugs with a pharmacological profile very similar to that of piracetam, showing much higher potency with respect to the reference. Among the compounds studied, 7 (DM 232) shows outstanding potency, being active at the dose of 0. 001 mg kg(-1) sc.


Assuntos
Desenho de Fármacos , Nootrópicos/síntese química , Nootrópicos/farmacologia , Piperazinas/síntese química , Piperazinas/farmacologia , Pirróis/síntese química , Pirróis/farmacologia , Agonistas alfa-Adrenérgicos , Amnésia/induzido quimicamente , Amnésia/tratamento farmacológico , Amnésia/prevenção & controle , Animais , Aprendizagem da Esquiva/efeitos dos fármacos , Baclofeno , Clonidina , Relação Dose-Resposta a Droga , Agonistas GABAérgicos , Mecamilamina , Camundongos , Estrutura Molecular , Antagonistas Muscarínicos , Nicotina/antagonistas & inibidores , Piperazinas/uso terapêutico , Piracetam/farmacologia , Pirróis/uso terapêutico , Escopolamina
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