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1.
J Cardiovasc Surg (Torino) ; 60(5): 589-598, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28548474

RESUMO

BACKGROUND: The chimney technique has been developed for the treatment of complex aortic aneurysms. We analyzed the midterm to long-term outcomes of this approach from a single-center experience. METHODS: From October 2008 to July 2016, 58 patients underwent endovascular aortic aneurysm repair using the chimney technique. Indications for treatment were thoracic aortic aneurysm (TAA) (N.=11), thoracoabdominal aortic aneurysm (TAAA) (N.=2), pararenal aortic aneurysm (PAAA) (N.=15), aortoiliac/isolated hypogastric artery aneurysm (N.=25), type I endoleak after previous TEVAR/EVAR (N.=4), proximal pseudoaneurysm after AAA open repair (N.=1). Elective (82.8%) and emergent (17.2%) procedures were included. RESULTS: The immediate technical success was 100%. Single, double and triple chimneys were performed in 46, 10, and two patients, respectively. Overall, 61 target vessels (three left common carotid arteries, eight left subclavian arteries, three celiac trunks, three superior mesenteric arteries, 19 renal arteries and 25 hypogastric arteries) were involved. Postoperative mortality was 0. No neurologic complications were registered. Primary patency rate of the chimney stent/stent graft was 98.3%. Low-flow type I endoleak was observed in four patients (6.9%). Postoperative chimney graft re-intervention rate was 1.7%. The median follow-up was 32±20 months (range 3-96 months). Overall estimated survival at 12, 50, and 80 months was 100%, 89% and 44%, respectively. Estimated freedom from endoleak at 1, 12, 24, and 36 months was 96.5%, 95%, 95%, and 93%, respectively. One hypogastric artery stent-graft occluded at the 3rd month of follow-up. No reintervention was performed. CONCLUSIONS: Our experience with the chimney technique for aortic aneurysms from the aortic arch to the iliac axis shows promising and durable mid- and long-term results. Endograft oversizing, associated with the chimney graft diameter and length choice remain fundamental to reduce the risk of the most frequent procedure complications: type I endoleak and CG occlusion. The wider use of this technique should be justified in patients considered at high risk for open repair and/or not suitable for the custom-made branched/fenestrated endografts.


Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Aneurisma da Aorta Torácica/cirurgia , Implante de Prótese Vascular/métodos , Procedimentos Endovasculares/métodos , Idoso , Idoso de 80 Anos ou mais , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Aneurisma da Aorta Torácica/diagnóstico por imagem , Prótese Vascular , Implante de Prótese Vascular/efeitos adversos , Implante de Prótese Vascular/instrumentação , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/instrumentação , Feminino , Humanos , Masculino , Complicações Pós-Operatórias/etiologia , Intervalo Livre de Progressão , Desenho de Prótese , Estudos Retrospectivos , Fatores de Risco , Stents , Fatores de Tempo
2.
Clin Genet ; 93(3): 545-556, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28556904

RESUMO

Whole exome sequencing (WES) has made the identification of causative SNVs/InDels associated with rare Mendelian conditions increasingly accessible. Incorporation of softwares allowing CNVs detection into the WES bioinformatics pipelines may increase the diagnostic yield. However, no standard protocols for this analysis are so far available and CNVs in non-coding regions are totally missed by WES, in spite of their possible role in the regulation of the flanking genes expression. So, in a number of cases the diagnostic workflow contemplates an initial investigation by genomic arrays followed, in the negative cases, by WES. The opposite workflow may also be applied, according to the familial segregation of the disease. We show preliminary results for a diagnostic application of a single next generation sequencing panel permitting the concurrent detection of LOH and variations in sequences and copy number. This approach allowed us to highlight compound heterozygosity for a CNV and a sequence variant in a number of cases, the duplication of a non-coding region responsible for sex reversal, and a whole-chromosome isodisomy causing reduction to homozygosity for a WFS1 variant. Moreover, the panel enabled us to detect deletions, duplications, and amplifications with sensitivity comparable to that of the most widely used array-CGH platforms.


Assuntos
Predisposição Genética para Doença , Testes Genéticos , Variação Genética , Estudo de Associação Genômica Ampla , Sequenciamento de Nucleotídeos em Larga Escala , Adolescente , Adulto , Criança , Pré-Escolar , Variações do Número de Cópias de DNA , Feminino , Testes Genéticos/métodos , Estudo de Associação Genômica Ampla/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Mutação INDEL , Lactente , Perda de Heterozigosidade , Masculino , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA , Adulto Jovem
3.
Curr Med Chem ; 21(37): 4227-46, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25039774

RESUMO

Nowadays, the delivery of drugs by means of intravenously administered nanosized drug carriers - polymerdrug conjugates, liposomes and micelles, is technically possible. These delivery systems are mainly designed for tumour therapy, and accumulate passively into tumours by means of the well known EPR effect. Targeted nanocarriers, that additionally contain ligands for receptors expressed on cell surfaces, are also widely studied but products of this kind are not marketed, and only a few are in clinical trial. Polymeric nanoparticles (Np) able to deliver drugs to the CNS were pioneered in 1995; a number of papers have been published dealing with brain-targeted drug delivery using polymeric Np able to cross the BBB, mainly for the treatment of brain tumours. At present, however, the translation potential of these Np seems to have been exceeded by targeted liposomes, a platform based on a proven technology. This drug delivery system entered clinical trials soon after its discovery, while the challenges in formulation, characterization and manufacturing of brain-targeted polymeric Np and the cost/benefit ratio could be the factors that have prevented their development. A key issue is that it is virtually impossible to define the in vivo fate of polymers, especially in the brain, which is a regulatory requirement; perhaps this is why no progress has been made. The most advanced Np for brain tumours treatment will be compared here with the published data available for those in clinical trial for tumours outside the CNS, to highlight the knowledge gaps that still penalise these delivery systems. At present, new approaches for brain tumours are emerging, such as lipid Np or the use of monoclonal antibody (mAb)-drug conjugates, which avoid polymers. The success or failure in the approval of the polymeric Np currently in clinical trials will certainly affect the field. At present, the chances of their approval appear to be very low.


Assuntos
Encéfalo/metabolismo , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Desenho de Fármacos , Nanopartículas/química , Preparações Farmacêuticas/metabolismo , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/metabolismo , Portadores de Fármacos/síntese química , Humanos , Nanopartículas/metabolismo
4.
Curr Med Chem ; 21(6): 663-88, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24251566

RESUMO

Temporal lobe epilepsy (TLE) is frequently associated with hippocampal sclerosis, possibly caused by a primary brain injury that occurred a long time before the appearance of neurological symptoms. This type of epilepsy is characterized by refractoriness to drug treatment, so to require surgical resection of mesial temporal regions involved in seizure onset. Even this last therapeutic approach may fail in giving relief to patients. Although prevention of hippocampal damage and epileptogenesis after a primary event could be a key innovative approach to TLE, the lack of clear data on the pathophysiological mechanisms leading to TLE does not allow any rational therapy. Here we address the current knowledge on mechanisms supposed to be involved in epileptogenesis, as well as on the possible innovative treatments that may lead to a preventive approach. Besides loss of principal neurons and of specific interneurons, network rearrangement caused by axonal sprouting and neurogenesis are well known phenomena that are integrated by changes in receptor and channel functioning and modifications in other cellular components. In particular, a growing body of evidence from the study of animal models suggests that disruption of vascular and astrocytic components of the blood-brain barrier takes place in injured brain regions such as the hippocampus and piriform cortex. These events may be counteracted by drugs able to prevent damage to the vascular component, as in the case of the growth hormone secretagogue ghrelin and its analogues. A thoroughly investigation on these new pharmacological tools may lead to design effective preventive therapies.


Assuntos
Epilepsia do Lobo Temporal/etiologia , Epilepsia do Lobo Temporal/prevenção & controle , Animais , Lesões Encefálicas/complicações , Epilepsia do Lobo Temporal/fisiopatologia , Hipocampo/patologia , Humanos , Esclerose/complicações , Esclerose/fisiopatologia
5.
Curr Med Chem ; 19(20): 3353-87, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22680630

RESUMO

The clinical treatment of multifactorial pathologies (e.g. cancer, Alzheimer's disease, psychiatric disorders), is still a major challenge. Many researches have been published dealing with the design of multiple ligands, able to act at the same time towards several targets relevant for a given pathology. In the present review, the clinical results about these compounds have been reported, together with the design strategy adopted, in order to allow a critical evaluation of the outcomes of these efforts. What is emerging is that several effective design strategies of multitarget compounds are available, and the choice among these appears to be dependent on the therapeutic area considered. However, at present, besides multitarget drugs discovered during optimization efforts by means of phenotypic assays, drug coadministrations or fixed dose formulations appear to be more useful therapeutic options than designed multiple ligands; this scenario will change when systems biology will be able to select critical targets, i.e. nodal proteins that should be inhibited in order to obtain a therapeutic action; at this point, the design of multiple ligands will allow a renaissance of medicinal chemistry.


Assuntos
Desenho de Fármacos , Terapia de Alvo Molecular/métodos , Pesquisa , Animais , Humanos , Ligantes
6.
J Control Release ; 145(1): 49-57, 2010 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-20338201

RESUMO

Polymeric nanoparticles (Np) have been considered as strategic carriers for brain targeting. Specific ligands on the surface allowed the Np to cross the Blood-Brain Barrier (BBB) carrying model drugs within the brain district after their i.v. administration in experimental animals. It is known that sialic acid receptors are present in several organs, including in the brain parenchyma. Thus, in this paper, we prepared PLGA Np surface modified with a BBB-penetrating peptide (similopioid peptide) for BBB crossing and with a sialic acid residue (SA) for the interaction with brain receptors. This double coverage could allow to obtain novel targeted Np with a prolonged residence within the brain parenchyma, thus letting to reach a long-lasting brain delivery of drugs. The central analgesic activity of Loperamide (opioid drug, unable to cross the BBB) loaded in these novel Np was evaluated in order to point out the capability of the Np to reach and to remain in the brain. The results showed that the pharmacological effect induced by loaded Np administration remained significant over 24h. Using confocal and fluorescent microscopies, the novel Np were localized within the tissue parenchyma (brain, kidney, liver, spleen and lung). Finally, the biodistribution studies showed a localization of the 6% of the injected dose into the CNS over a prolonged time (24h). Notwithstanding an increased accumulation of SA-covered Np in those organs showing SA-receptors (liver, kidney, and lung), the pharmacological and biodistribution results are proofs of the ability of double targeted Np to enter the brain allowing the drug to be released over a prolonged time.


Assuntos
Encéfalo/efeitos dos fármacos , Portadores de Fármacos/química , Glicopeptídeos/química , Ácido Láctico/química , Ácido N-Acetilneuramínico/química , Nanopartículas/química , Ácido Poliglicólico/química , Animais , Encéfalo/metabolismo , Loperamida/administração & dosagem , Loperamida/farmacocinética , Loperamida/uso terapêutico , Masculino , Microscopia Eletrônica de Varredura , Especificidade de Órgãos , Dor/tratamento farmacológico , Tamanho da Partícula , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Ratos , Ratos Endogâmicos , Propriedades de Superfície , Distribuição Tecidual
7.
Mol Cell Endocrinol ; 314(1): 17-22, 2010 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-19772891

RESUMO

Histone deacetylase inhibitors (HDIs) are valuable drugs in breast cancer where estrogen receptor alpha (ER alpha) can be silenced by epigenetic modifications. We report the effect of the clinically available HDI, valproic acid (VPA), on ER alpha expression and function in ER-negative breast cancer cells, MDA-MB-231. VPA induced ER alpha mRNA and protein, while did not modify ER beta. In VPA-treated cells, we also observed: (1) a correct transcriptional response to estradiol after transfection with the luciferase gene under the control of an estrogen-responsive minimal promoter (ERE-TKluc); (2) increased expression of the ER-related transcription factor FoxA1; (3) estradiol-induced up-regulation of several estrogen-regulated genes (e.g. pS2, progesterone receptor); (4) inhibitory effect of tamoxifen on cell growth. In conclusion, the HDI VPA, inducing ER alpha and FoxA1, confers to MDA-MB 231 cells an estrogen-sensitive "phenotype", restoring their sensitivity to antiestrogen therapy.


Assuntos
Neoplasias da Mama , Linhagem Celular Tumoral/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Moduladores de Receptor Estrogênico , Receptor alfa de Estrogênio/metabolismo , Ácido Valproico/farmacologia , Animais , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Proliferação de Células/efeitos dos fármacos , Estradiol/metabolismo , Estradiol/farmacologia , Antagonistas de Estrogênios/farmacologia , Moduladores de Receptor Estrogênico/metabolismo , Moduladores de Receptor Estrogênico/uso terapêutico , Receptor alfa de Estrogênio/genética , Receptor beta de Estrogênio/genética , Receptor beta de Estrogênio/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Fator 3-alfa Nuclear de Hepatócito/genética , Fator 3-alfa Nuclear de Hepatócito/metabolismo , Humanos , Tamoxifeno/farmacologia , Transcrição Gênica/efeitos dos fármacos
8.
Clin Genet ; 73(4): 346-52, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18279436

RESUMO

Cystic fibrosis (CF) is mainly caused by small deletions or missense mutations in the CFTR gene. The CF mutation database lists more than 35 large rearrangements that may escape detection using polymerase chain reaction-base techniques. The Innogenetics assay, the denaturing high-performance liquid chromatography and sequencing screening showed a mutation detection rate of 92.6% in our population. We report here the results of multiplex ligation-dependent probe amplification (MLPA) screening for CFTR gene rearrangements, performed on the unidentified alleles of our CF patients. Our sample population consists of 692 non-related Italian CF patients (for a total of 1384 alleles), followed at CF Centres in the Lombardia Region. MLPA analysis was performed in 49 patients who still had one or two unidentified alleles (for a total of 52 unidentified alleles) after extensive analysis of CFTR gene. All patients who were studied had the classical form of CF. We characterized nine different deletions and a new duplication. The deletion of exons 22-23 (7/82) was the most frequent in our cohort. The search for deletion/duplications of the CFTR gene has made it possible to reach a 94.1% detection rate, with an improvement (1.6%) of the carrier detection rate in the Italian population.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/genética , Deleção de Genes , Duplicação Gênica , Rearranjo Gênico , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Técnicas de Amplificação de Ácido Nucleico
9.
J Control Release ; 122(1): 1-9, 2007 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-17651855

RESUMO

Polymeric nanoparticles (Np) represent one of the most innovative non-invasive approaches for the drug delivery to the central nervous system (CNS). It is known that the ability of the Np to cross the Blood Brain Barrier (BBB), thus allowing the drugs to exert their pharmacological activity in the central nervous district, is linked to their surface characteristics. Recently it was shown that the biocompatible polyester poly(d,l-lactide-co-glycolide) (PLGA) derivatized with the peptide H(2)N-Gly-l-Phe-d-Thr-Gly-l-Phe-l-Leu-l-Ser(O-beta-d-Glucose)-CONH(2) [g7] was a useful starting material for the preparation of Np (g7-Np); moreover, fluorescent studies showed that these Np were able to cross the BBB. In this research, g-7 Np were loaded with Loperamide in order to assess their ability as drug carriers for CNS, and with Rhodamine-123, in order to qualitatively determine their biodistribution in different brain macro-areas. A pharmacological evidence is given that g7-Np are able to cross the BBB, ensuring, for the first time, a sustained release of the embedded drug, and that these Np are able to reach all the brain areas here examined. The ability to enter the CNS appears to be linked to the sequence of the peptidic moiety present on their surface.


Assuntos
Barreira Hematoencefálica/metabolismo , Encéfalo/metabolismo , Ácido Láctico/farmacocinética , Loperamida/farmacocinética , Nanopartículas/química , Oligopeptídeos/farmacocinética , Ácido Poliglicólico/farmacocinética , Polímeros/farmacocinética , Rodamina 123/farmacocinética , Animais , Antidiarreicos/administração & dosagem , Antidiarreicos/química , Antidiarreicos/farmacocinética , Sistemas de Liberação de Medicamentos , Ácido Láctico/administração & dosagem , Ácido Láctico/química , Loperamida/administração & dosagem , Loperamida/química , Masculino , Oligopeptídeos/administração & dosagem , Oligopeptídeos/química , Medição da Dor/efeitos dos fármacos , Ácido Poliglicólico/administração & dosagem , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Polímeros/administração & dosagem , Polímeros/química , Ratos , Ratos Wistar , Rodamina 123/administração & dosagem , Rodamina 123/química
10.
Horm Metab Res ; 39(4): 288-94, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17447168

RESUMO

Human sex hormone-binding globulin inhibits the effects of estradiol on proliferation and apoptosis of breast cancer cells. We report here the effect of sex hormone-binding globulin on estradiol regulation of gene expression in MCF-7 breast cancer cells using a selected set of genes. Estradiol upregulates genes that are positive regulators of proliferation (e.g., bcl-2, c-fos, c-myc, cyclin D) or/and related to more aggressive form of breast cancer (e.g. BRCA-1, EGF-R) and downregulates two genes (c-jun and ERalpha). Sex hormone-binding globulin modulates only a selected group of estradiol-controlled genes (inhibiting upregulation of bcl-2, c-myc, EGF-R, PR, and downregulation of ERalpha), starting 48 hours after treatment. Our study demonstrates that in breast cancer cells, sex hormone-binding globulin is effective on few selected genes which are involved in cell growth and apoptosis or related to cell estrogen-dependence and that the protein regulation of estradiol effect is selected and specific. Sex hormone-binding globulin action in estrogen breast cancer cells is strongly associated to cell growth and estrogen-sensitivity.


Assuntos
Estradiol/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Globulina de Ligação a Hormônio Sexual/farmacologia , Western Blotting , Neoplasias da Mama/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Receptor alfa de Estrogênio/biossíntese , Feminino , Humanos , Análise de Sequência com Séries de Oligonucleotídeos , Prolactina/biossíntese , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/efeitos dos fármacos
11.
Thyroid ; 17(2): 91-9, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17316109

RESUMO

OBJECTIVE: Multimodal treatments do not meaningfully improve survival of anaplastic thyroid cancer. Consequently, new effective therapeutic modalities are needed. The use of paclitaxel is under clinical investigation; it shows about a 50% response rate, but it is not able to alter the fatal outcome for patients with anaplastic carcinoma. High energy shock waves (HESW) have been shown to cause a transient increase in the permeability of cell membranes thus allowing higher intracellular drug concentrations. 5-Aminolevulinic acid (ALA) is used in the photodynamic therapy (PDT) of cancer, and HESW are under evaluation for their use as an activator in ALA-PDT. DESIGN: We investigated the effect of HESW produced by a piezoelectric generator on the sensitivity to paclitaxel and ALA treatments of two different anaplastic thyroid cancer cell lines (ARO and CAL-62). Cells, treated sequentially with ALA and paclitaxel were exposed to HESW; thereafter, cell viability and apoptosis induction were evaluated. MAIN OUTCOME: Combined exposure to ALA, paclitaxel, and shock waves resulted in a significant enhancement of cytotoxicity and induction of apoptosis in thyroid cancer cells with respect to cells treated with paclitaxel alone. CONCLUSIONS: These preliminary data suggest the possibility of using HESW and ALA in combination with paclitaxel as a promising new therapy in the treatment of anaplastic thyroid cancer.


Assuntos
Ácido Aminolevulínico/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Carcinoma/terapia , Permeabilidade da Membrana Celular , Ondas de Choque de Alta Energia , Paclitaxel/farmacologia , Fotoquimioterapia , Neoplasias da Glândula Tireoide/terapia , Ácido Aminolevulínico/metabolismo , Apoptose/efeitos dos fármacos , Carcinoma/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Terapia Combinada , Humanos , Paclitaxel/farmacocinética , Neoplasias da Glândula Tireoide/patologia
12.
Med Chem ; 2(1): 39-45, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16787354

RESUMO

A new series of 8-halogen-4,4a,5,6-tetrahydrothieno[2,3-h]cinnolinone-N2-alkanoic acids was prepared and tested for aldose reductase (ALR2) inhibitory activities. These compounds showed significant inhibitory activity against bovine lens ALR2, with the best compound 2e showing an IC(50) value of 31.4 microM. The presence of the C8-substituents here studied (Cl, Br) on the thienocinnolinone scaffold caused a decrease of the inhibitory potency by a factor of about 4 with respect to the unsubstituted parent compound, while the presence of a C8-methyl group, considered in a previous paper decreased the activity by a factor of about 2. Moreover, the length of the N2 alkanoic chain influences strongly the enzyme inhibitory activity. While most of the carboxylic acids ALR2 inhibitors are acetic acid derivatives, in the case of thienocinnolinone compounds, homologues higher than acetic acids showed to be more active.


Assuntos
Aldeído Redutase/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Cristalino/efeitos dos fármacos , Tiofenos/farmacologia , Aldeído Redutase/metabolismo , Animais , Ácidos Carboxílicos/síntese química , Bovinos , Inibidores Enzimáticos/síntese química , Cristalino/citologia , Cristalino/metabolismo , Relação Estrutura-Atividade , Tiofenos/síntese química
13.
Biomaterials ; 26(19): 4189-95, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15664646

RESUMO

Cellular localization of nanoparticles (Np) represents an important target in the understanding of their distribution after endovenous injection. The need of suitable devices and methodologies capable to detect Np in tissues or in cellular districts can be satisfied by Np which have to be easily recognizable by simple methods. Conjugations of poly(D,L-lactide-co-glycolide) with fluorescein and biotin allow fluorescent and immuno-histochemically active Np to be obtained. The fluorescein Np are detectable using fluorescent microscopy whereas biotin Np can be detected by optical microscopy after streptavidin-biotin-peroxidase complexation. In vivo experiments confirm the ability of these particles to be easily detected in the brain parenchyma or in the liver cell population according to the infusion pathway.


Assuntos
Biotina/farmacocinética , Encéfalo/citologia , Fluoresceína/farmacocinética , Ácido Láctico/química , Fígado/citologia , Microscopia de Fluorescência/métodos , Nanoestruturas/ultraestrutura , Ácido Poliglicólico/química , Polímeros/química , Animais , Biotina/química , Encéfalo/metabolismo , Materiais Revestidos Biocompatíveis/química , Fluoresceína/química , Corantes Fluorescentes , Infusões Intravenosas , Fígado/metabolismo , Teste de Materiais , Nanoestruturas/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Ratos , Distribuição Tecidual
14.
Eur J Pharm Sci ; 21(4): 545-52, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14998586

RESUMO

A novel series of tetrahydrothieno[2,3-h]cinnolinone derivatives were synthesized and evaluated in vitro for their ability to inhibit aldose reductase (ALR2), an enzyme involved in the appearance of diabetic complications. Compounds 2e and 2j exert a remarkable inhibitory effect, with IC(50) of 7.6 and 18 microM, respectively. These compounds incorporate a valid pharmacophore for aldose reductase inhibitory activity represented by a thienocinnolinone template linked through a pentamethylene spacer to a carboxylic function.


Assuntos
Aldeído Redutase/antagonistas & inibidores , Ácidos Carboxílicos/síntese química , Inibidores Enzimáticos/síntese química , Tiofenos/síntese química , Aldeído Redutase/metabolismo , Animais , Ácidos Carboxílicos/farmacologia , Inibidores Enzimáticos/farmacologia , Suínos , Tiofenos/farmacologia
15.
J Viral Hepat ; 10(2): 95-102, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12614465

RESUMO

The tissue tropism and possible correlation with liver disease of the TT virus (TTV) as well as its prevalence and genotype distribution remain undefined. TTV-DNA was investigated in paired sera and tissue samples from 144 patients, and sera and cerebrospinal fluids (CSF) from additional six subjects. Of the 144 tissue samples, 128 were liver biopsy specimens from subjects with hepatic disease while 16 were surgically obtained nonliver specimens from patients with extrahepatic disease. TTV cloning, sequencing and genotype analyses were performed on isolates from sera, tissue specimens and peripheral blood mononuclear cells of two patients with hepatic and four patients with extrahepatic pathologies, as well as from sera and CSFs of two subjects. TTV was found in 100% of the examined tissues and in 60.1 and 50% of sera from patients with hepatic and extrahepatic pathologies, respectively. Moreover, TTV was detected in four of the six CSFs analysed but only in two correspondent sera. Genotyping revealed the coexistence of multiple TTV genotypes and genetic variants in each infected individual, and the analysis of TTV mRNA showed the presence of transcripts in all the six different tissues studied. These results indicate that the entire adult population in our area is more likely infected by TTV, although several subjects are not viraemic and that TTV infects many different human tissues and is able to invade the central nervous system.


Assuntos
Infecções por Vírus de DNA/virologia , DNA Viral/metabolismo , Torque teno virus/fisiologia , Adulto , Idoso , Sequência de Bases , Infecções por Vírus de DNA/sangue , Infecções por Vírus de DNA/líquido cefalorraquidiano , DNA Viral/sangue , DNA Viral/líquido cefalorraquidiano , Feminino , Hepacivirus/crescimento & desenvolvimento , Vírus da Hepatite B/crescimento & desenvolvimento , Hepatite B Crônica/virologia , Hepatite C Crônica/virologia , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , Alinhamento de Sequência , Torque teno virus/genética , Torque teno virus/crescimento & desenvolvimento
16.
Pharmazie ; 58(2): 140-2, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12641333

RESUMO

Tecostanine (1) was isolated from Tecoma stans leaves. Its sterochemistry was elucidated as well as its antihyperglycemic activity and its affinity to opioid and nicotinic receptors. The oxalate salt of 1 did not significantly affect blood glucose levels in normoglycaemic and hyperglycaemic rats. It did not appear to interact with opioid receptors (mu type) and showed only moderate affinity to the nicotinic receptor.


Assuntos
Alcaloides/química , Alcaloides/farmacologia , Bignoniaceae/química , Hipoglicemiantes/química , Hipoglicemiantes/farmacologia , Plantas Medicinais/química , Terpenos/química , Terpenos/farmacologia , Animais , Cristalografia por Raios X , Espectroscopia de Ressonância Magnética , Masculino , México , Modelos Moleculares , Conformação Molecular , Ratos , Ratos Sprague-Dawley , Receptores Nicotínicos/efeitos dos fármacos , Receptores Opioides/efeitos dos fármacos
17.
Bioorg Med Chem ; 10(4): 1077-84, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11836118

RESUMO

Several (Z)-5-arylidene-2,4-thiazolidinediones were synthesized and tested as aldose reductase inhibitors (ARIs). The most active of the N-unsubstituted derivatives (2) exerted the same inhibitory activity of Sorbinil. The introduction of an acetic side chain on N-3 of the thiazolidinedione moiety led to a marked increase in lending inhibitory activity, conducting to the discovery of a very potent ARI (4c), whose activity level (IC50=0.13 microM) was in the same range of Tolrestat. Moreover, the corresponding methyl esters (3), devoid of any acidic functionality, showed appreciable inhibitory activity similar to that of the N-unsubstituted compounds. It was also found that the substitution pattern on the 5-benzylidene moiety markedly influenced the activity of N-unsubstituted 2,4-thiazolidinediones 2, compounds with substituents at the meta position being generally more effective than the para-substituted ones; however, this SAR was not evidenced in acetates 3 and acids 4.


Assuntos
Aldeído Redutase/antagonistas & inibidores , Inibidores Enzimáticos/síntese química , Imidazolidinas , Tiazóis/farmacologia , Tiazolidinedionas , Animais , Bovinos , Inibidores Enzimáticos/farmacologia , Hipoglicemiantes/síntese química , Hipoglicemiantes/farmacologia , Imidazóis/química , Imidazóis/farmacologia , Concentração Inibidora 50 , Espectroscopia de Ressonância Magnética , NADP/metabolismo , Naftalenos/química , Naftalenos/farmacologia , Relação Estrutura-Atividade , Tiazóis/síntese química
18.
Eur J Med Chem ; 36(9): 697-703, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11672879

RESUMO

On the basis of the results of molecular modelling studies performed on the aldose reductase (ALR2) inhibitor 7-hydroxy-2-(4'-hydroxybenzyl)-4H-1-benzopyran-4-one (compound A) bound at the active site of the enzyme, we synthesised and tested on bovine and human ALR2 several derivatives modified at position 2 of the benzopyran moiety, in order to confirm the hypothesised binding mode of this compound. The substitution of the methylene bridge with the isosteric sulphur substituent gives an active derivative, while substitution with a polar NH causes a decrease in inhibitory activity; this is in accordance to the previously reported structure in which the methylene linker was found to be adjacent to a hydrophobic aminoacid (Leu300). Among the substituents at 4' position examined, the most favourable for inhibitory activity are those able to act as hydrogen bond donors, supporting the hypothesis of the importance of the interaction with Thr113 for the inhibition of the enzyme.


Assuntos
Aldeído Redutase/antagonistas & inibidores , Benzopiranos/síntese química , Benzopiranos/farmacologia , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacologia , Animais , Bovinos , Cromatografia em Camada Fina , Humanos , Concentração Inibidora 50 , Espectroscopia de Ressonância Magnética , Relação Estrutura-Atividade
19.
Exp Eye Res ; 71(5): 515-21, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11040087

RESUMO

In order to define the ability of bovine lens aldose reductase (ALR2) to generate polyols from aldoses, the quantitative determination of glycerol in the presence of glyceraldehyde was performed by gas chromatography after derivatization with trifluoroacetic anhydride. The proposed method appears to be useful in quantifying low amounts of glycerol in the presence of relatively high concentrations of glyceraldehyde and in following glycerol formation in enzyme assay conditions. The generation of one equivalent of glycerol in the presence of ALR2, is paralleled by the oxidation of one equivalent of NADPH. A similar result was obtained when S-glutathionyl-modified ALR2 was used, instead of the native enzyme, as a catalyst of glyceraldehyde reduction. Sorbinil, a classical ALR2 inhibitor, present in the enzyme assay mixture, inhibits to the same extent both NADPH oxidation and glycerol formation. The demonstration of the stoichiometric ratio of 1:1 occurring in the presence of bovine lens ALR2 between the synthesis of glycerol from D, L -glyceraldehyde and the oxidation of NADPH, rules out doubts concerning the ability of the enzyme to catalyse the reduction of aldoses to the corresponding polyalcohols. Possible autooxidation processes of glyceraldehyde, in the enzyme assay conditions, appear to be irrelevant with respect to the enzyme-catalysed reduction of the aldose. This would indicate that the spectrophotometric monitoring of NADPH oxidation at 340 nm, in the presence of ALR2, is a reliable method to assay the enzyme activity.


Assuntos
Aldeído Redutase/fisiologia , Gliceraldeído/metabolismo , NADP/metabolismo , Aldeído Redutase/antagonistas & inibidores , Animais , Catálise , Bovinos , Cromatografia Gasosa , Fluoracetatos , Glicerol/metabolismo , Cristalino/enzimologia , Oxirredução , Ácido Trifluoracético/farmacologia
20.
Drug Alcohol Depend ; 60(2): 121-32, 2000 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-10940539

RESUMO

A large series of beta-carbolines was examined for their ability to bind at [3H]agonist-labeled 5-HT(2A) serotonin receptors. Selected beta-carbolines were also examined at 5-HT(2C) serotonin receptors, 5-HT(1A) serotonin receptors, dopamine D(2) receptors, and benzodiazepine receptors. Indolealkylamines and phenylisopropylamines were also evaluated in some of these binding assays. The beta-carbolines were found to bind with modest affinity at 5-HT(2A) receptors, and affinity was highly dependent upon the presence of ring substituents and ring saturation. The beta-carbolines displayed little to no affinity for 5-HT(1A) serotonin receptors, dopamine D(2) receptors and, with the exception of beta-CCM, for benzodiazepine receptors. Examples of beta-carbolines, indolealkylamines (i.e. N,N-dimethyltryptamine analogs), and phenylisopropylamines have been previously shown to produce common stimulus effects in animals trained to discriminate the phenylisopropylamine hallucinogen DOM (i.e. 1-(2, 5-dimethoxy-4-methylphenyl)-2-aminopropane) from vehicle. Although the only common receptor population that might account for this action is 5-HT(2A), on the basis of a lack of enhanced affinity for agonist-labeled 5-HT(2A) receptors, as well as on their lack of agonist action in the PI hydrolysis assay, it is difficult to conclude that the beta-carbolines behave in a manner consistent with that of other classical hallucinogens.


Assuntos
Carbolinas/metabolismo , Receptores de Dopamina D2/metabolismo , Receptores de GABA-A/metabolismo , Receptores de Serotonina/metabolismo , Animais , Carbolinas/química , Linhagem Celular , Hidrólise , Fosfatos de Inositol/metabolismo , N,N-Dimetiltriptamina/análogos & derivados , N,N-Dimetiltriptamina/metabolismo , Ratos , Receptores 5-HT1 de Serotonina
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