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1.
Hepatology ; 57(3): 890-6, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22473858

RESUMEN

UNLABELLED: Interleukin (IL)28B polymorphisms have been associated with interferon (IFN)-induced viral clearance in patients with chronic hepatitis C. Whether this is also true for patients with the difficult-to-cure hepatitis B e antigen (HBeAg)-negative chronic hepatitis B (CHB) is unknown. One hundred and one HBeAg-negative patients (92% genotype D) with compensated CHB (84% males, 46 years; hepatitis B virus [HBV] DNA: 6.0 log cp/mL; alanine aminotransferase [ALT]: 136 IU/L; 42% with cirrhosis) were followed up for a median of 11 years (range, 1-17) after a median of 23 months (range, 10-48) of either standard or pegylated (Peg)-IFN-alpha therapy. A post-treatment response was defined as hepatitis B surface antigen (HBsAg) clearance with or without antibody to hepatitis B surface antigen (anti-HBs) seroconversion. The rs12979860 (C>T) genotype in the IL28B locus was assessed in serum samples by using Custom TaqMan SNP Genotyping Assays (Applied Biosystems, Carlsbad, CA). During a median of 11 years of post-treatment follow-up, 21 patients (21%) cleared serum HBsAg, including 15 who developed>10 IU/mL of anti-HBs titers. Forty-eight patients (47%) had CC genotype, 42 (42%) had CT, and 11 (11%) had TT, with the allelic frequency being 68% for C allele and 32% for T allele. The rate of serum HBsAg clearance was 29% (n=14) in CC compared to 13% (n=7) in non-CC, genotype carriers (P=0.039). Baseline HBV DNA levels<6 log cp/mL (odds ratio [OR], 11.9; 95% confidence interval [CI]: 2.8-50.6; P=0.001), ALT levels>136 IU/L (OR, 6.5; 95% CI: 1.8-22.5; P=0.003), duration of IFN (OR, 1.16; 95% CI: 1.02-1.31; P=0.021), and genotype CC (OR, 3.9; 95% CI: 1.1-13.2; P=0.025) independently predicted HBsAg clearance. CONCLUSIONS: IL28B polymorphism is an additional predictor of off-therapy IFN-related HBsAg seroclearance to be used in the pretreatment stratification of HBeAg-negative patients chronically infected by genotype D of HBV.


Asunto(s)
Hepacivirus/genética , Hepatitis C Crónica/tratamiento farmacológico , Hepatitis C Crónica/genética , Interferón-alfa/uso terapéutico , Interleucinas/genética , Polietilenglicoles/uso terapéutico , Adulto , Antivirales/uso terapéutico , Farmacorresistencia Viral/genética , Femenino , Estudios de Seguimiento , Pruebas Genéticas , Genotipo , Hepacivirus/inmunología , Antígenos de Superficie de la Hepatitis B/sangre , Antígenos de Superficie de la Hepatitis B/genética , Antígenos e de la Hepatitis B/sangre , Antígenos e de la Hepatitis B/genética , Hepatitis C Crónica/inmunología , Humanos , Interferón alfa-2 , Interferones , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple/genética , Valor Predictivo de las Pruebas , Proteínas Recombinantes/uso terapéutico , Estudios Retrospectivos
2.
Biomaterials ; 27(23): 4256-65, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16620960

RESUMEN

The photodynamic activity of a carrier-sensitizer system consisting of heterotopic colloidal nanoparticles (diameter 100-1000 nm) of a cationic amphiphilic cyclodextrin, heptakis(2-omega-amino-O-oligo(ethylene oxide)-6-hexylthio)-beta-CD (SC6CDNH2) encapsulating the anionic 5,10,15,20-tetrakis(4-sulfonatophenyl)-21H,23H-porphyrin (TPPS) is investigated by an interdisciplinary approach involving the combination of time-resolved absorption and emission techniques with in vitro studies on cultured tumor cells. In a range of TPPS:SC6CDNH2 molar ratios between 1:10 and 1:50 these nanoparticles preserve the photodynamic properties of the entrapped photoactive agent. In fact, the triplet state of TPPS is efficiently populated, very long-lived and, as a consequence, able to produce singlet oxygen (the essential species for the photodynamic action) with quantum yield comparable to the free TPPS. Photodynamic efficacy of the carrier/sensitizer system is proven by in vitro studies on tumor Hela cells treated with TPPS:SC6CDNH2 at different molar ratio, showing significant cells death upon illumination with visible light.


Asunto(s)
Ciclodextrinas , Sistemas de Liberación de Medicamentos , Nanoestructuras , Neoplasias/tratamiento farmacológico , Fotoquimioterapia , Porfirinas , Tensoactivos , Células HeLa , Humanos
3.
J Med Chem ; 49(2): 709-15, 2006 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-16420056

RESUMEN

Isoxazolidinyl polycyclic aromatic hydrocarbons (isoxazolidinyl-PAHs) have been synthesized in good yields by 1,3-dipolar cycloaddition methodology promoted by microwave irradiation. The structures of the obtained cycloadducts have been determined by NOE experiments and supported by computational studies at the AM1 level. The cytotoxicity and antiviral activity of the synthesized compounds have been investigated. In particular, compounds 7c and 7e show high levels of cytotoxicity on MOLT-3 leukemia cells; 7e exerts a remarkable enhancing activity on apoptosis caused by anti-fas antibody addition. Furthermore, compounds 7b and 8b exhibit specific antiviral effects against the Punta Toro virus.


Asunto(s)
Antineoplásicos/síntesis química , Antivirales/síntesis química , Sustancias Intercalantes/síntesis química , Isoxazoles/síntesis química , Hidrocarburos Policíclicos Aromáticos/síntesis química , Animales , Antracenos/síntesis química , Antracenos/química , Antracenos/farmacología , Antineoplásicos/química , Antineoplásicos/farmacología , Antivirales/química , Antivirales/farmacología , Apoptosis , Línea Celular Tumoral , Chlorocebus aethiops , ADN/química , Virus ADN/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Sustancias Intercalantes/química , Sustancias Intercalantes/farmacología , Isoxazoles/química , Isoxazoles/farmacología , Fenantrenos/síntesis química , Fenantrenos/química , Fenantrenos/farmacología , Hidrocarburos Policíclicos Aromáticos/química , Hidrocarburos Policíclicos Aromáticos/farmacología , Pirenos/síntesis química , Pirenos/química , Pirenos/farmacología , Virus ARN/efectos de los fármacos , Estereoisomerismo , Relación Estructura-Actividad , Células Vero , Receptor fas/fisiología
4.
J Med Chem ; 48(5): 1389-94, 2005 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-15743182

RESUMEN

Phosphonated carbocyclic 2'-oxa-3'-aza-nucleosides have been synthesized in good yields by 1,3-dipolar cycloaddition methodology. The cytotoxicity and the reverse transcriptase inhibitory activity of the obtained compounds have been investigated. Phosphonated carbocyclic 2'-oxa-3'-aza-nucleosides, while showing low levels of cytotoxicity, exert a specific inhibitor activity on two different reverse transcriptases, which is comparable with that of AZT, opening new perspectives on their possible use as therapeutic agents, in anti-retroviral and anti-HBV chemotherapy.


Asunto(s)
Antivirales/síntesis química , Compuestos Aza/síntesis química , Nucleósidos/síntesis química , Organofosfonatos/síntesis química , Inhibidores de la Transcriptasa Inversa/síntesis química , Antivirales/farmacología , Antivirales/toxicidad , Compuestos Aza/farmacología , Compuestos Aza/toxicidad , Humanos , Técnicas In Vitro , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/enzimología , Óxidos de Nitrógeno/química , Nucleósidos/farmacología , Nucleósidos/toxicidad , Organofosfonatos/farmacología , Organofosfonatos/toxicidad , Inhibidores de la Transcriptasa Inversa/farmacología , Inhibidores de la Transcriptasa Inversa/toxicidad , Estereoisomerismo , Relación Estructura-Actividad
5.
Bioorg Med Chem ; 12(14): 3903-9, 2004 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-15210157

RESUMEN

The synthesis of 4'-alpha-C-branched N,O-nucleosides has been described, based on the 1,3-dipolar cycloaddition of nitrones with vinyl acetate followed by coupling with silylated nucleobases, The obtained compounds have been evaluated for their activity against HSV-1, HSV-2, HTLV-1. Cytotoxicity and apoptotic activity have been also investigated: compound 10c shows moderate apoptotic activity in Molt-3 cells.


Asunto(s)
Antivirales/síntesis química , Antivirales/farmacología , Nucleósidos/síntesis química , Nucleósidos/farmacología , Apoptosis/efectos de los fármacos , Línea Celular , Herpesvirus Humano 1/efectos de los fármacos , Herpesvirus Humano 2/efectos de los fármacos , Virus Linfotrópico T Tipo 1 Humano/efectos de los fármacos , Humanos , Espectroscopía de Resonancia Magnética , Espectrometría de Masa Bombardeada por Átomos Veloces
6.
Comp Biochem Physiol C Toxicol Pharmacol ; 139(4): 295-301, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15683841

RESUMEN

Crude extracts of the coelenterate Aiptasia mutabilis (Anthozoa, Aiptasiidae) nematocysts have been tested for their cytotoxicity of Vero and HEp-2 cells monolayers. The results indicate that the nematocyte venom contains one or more toxins with an extremely powerful cytolytic activity. An extract containing the equivalent of as little as 0.6 nematocysts/microL is sufficient to induce significant cellular necrosis, and IC50 can be estimated to be ca. 2 nematocysts/microL on Vero cells. These values are 1-2 orders of magnitude lower than those reported so far for other sea anemone venoms. The extreme potency is accompanied by poor stability of the venom that is readily inactivated by moderate heat and by buffers at non-neutral pH values. The extract is unstable even when kept for short times at 4 degrees C, or after storage at -20 degrees C. Separation of crude venom by affinity chromatography on ConA-Sepharose allowed us to identify two main components with molecular masses of 95 and 31 kDa, respectively, as responsible for the cytolytic properties of A. mutabilis nematocyst extract.


Asunto(s)
Venenos de Cnidarios/toxicidad , Necrosis/inducido químicamente , Animales , Chlorocebus aethiops , Venenos de Cnidarios/aislamiento & purificación , Humanos , Anémonas de Mar , Células Vero
7.
J Med Chem ; 46(17): 3696-702, 2003 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-12904074

RESUMEN

Enantiomers of 4'-aza-2',3'-dideoxynucleosides have been prepared by two different synthetic approaches, on the basis of 1,3-dipolar cycloaddition of a chiral nitrone. Cytotoxicity and apoptotic activity have been investigated. (5'S)-5-Fluoro-1-isoxazolidin-5-yl-1H-pyrimidine-2,4-dione [(-)-AdFU], while showing low level of cytotoxicity, is a good inductor of apoptosis on lymphoid and monocytoid cells, acting as a strong potentiator of Fas-induced cell death.


Asunto(s)
Didesoxinucleósidos/síntesis química , Isoxazoles/síntesis química , Uridina/síntesis química , Antineoplásicos/síntesis química , Antineoplásicos/farmacología , Antineoplásicos/toxicidad , Antivirales/síntesis química , Antivirales/farmacología , Antivirales/toxicidad , Apoptosis , Caspasa 3 , Caspasa 8 , Caspasa 9 , Inhibidores de Caspasas , Caspasas/metabolismo , Línea Celular , Didesoxinucleósidos/farmacología , Didesoxinucleósidos/toxicidad , Humanos , Isoxazoles/farmacología , Isoxazoles/toxicidad , Tejido Linfoide/citología , Conformación Molecular , Monocitos/citología , Teoría Cuántica , Estereoisomerismo , Relación Estructura-Actividad , Células Tumorales Cultivadas , Uridina/análogos & derivados , Uridina/farmacología , Uridina/toxicidad , Receptor fas/fisiología
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