RESUMEN
In the INFORM-1 study, 73 patients with chronic hepatitis C virus infection received mericitabine plus danoprevir for up to 13 days. Seventy-two patients experienced a continuous decline in HCV RNA levels during treatment, and of these patients, 14 had viral loads that remained >1,000 IU/ml by day 13 and 1 met the definition for viral breakthrough. In-depth NS5B and NS3/4A population and clonal sequencing studies and mericitabine and danoprevir drug susceptibility testing were performed to assess the variability and quasispecies dynamics before and upon monotherapy or dual therapy. Sequence analysis of the viral quasispecies indicated that the mericitabine resistance mutation S282T was not present at baseline, nor was it selected (even at a low level) during treatment. Protease inhibitor resistance mutations, either as predominant or as minority species, were detected in 18 patients at baseline. No enrichment of minority protease inhibitor-resistant variants present at baseline was observed during treatment; viral population samples were fully susceptible to mericitabine and/or danoprevir, despite the presence within their quasispecies of minority variants confirmed to have reduced susceptibility to danoprevir or other protease inhibitors. It was also observed that certain NS3 amino acid substitutions affected protease inhibitor drug susceptibility in a compound-specific manner and varied with the genetic context. In summary, the slower kinetics of viral load decline observed in some patients was not due to the selection of danoprevir or mericitabine resistance during treatment. Over 2 weeks' therapy, mericitabine suppressed the selection of danoprevir resistance, results that could differ upon longer treatment periods.
Asunto(s)
Antivirales/uso terapéutico , Desoxicitidina/análogos & derivados , Inhibidores Enzimáticos/uso terapéutico , Hepacivirus/efectos de los fármacos , Hepatitis C Crónica/tratamiento farmacológico , Lactamas/uso terapéutico , ARN Viral/antagonistas & inhibidores , Sulfonamidas/uso terapéutico , Adulto , Antivirales/farmacología , Ciclopropanos , Desoxicitidina/farmacología , Desoxicitidina/uso terapéutico , Método Doble Ciego , Esquema de Medicación , Farmacorresistencia Viral/efectos de los fármacos , Farmacorresistencia Viral/genética , Quimioterapia Combinada , Inhibidores Enzimáticos/farmacología , Hepacivirus/enzimología , Hepacivirus/genética , Hepatitis C Crónica/virología , Humanos , Isoindoles , Lactamas/farmacología , Lactamas Macrocíclicas , Mutación , Placebos , Prolina/análogos & derivados , Sulfonamidas/farmacología , Carga Viral/efectos de los fármacos , Proteínas no Estructurales Virales/antagonistas & inhibidoresRESUMEN
Dorsal root ganglion neurons express a wide repertoire of sodium channels with different properties. Here, we report the cloning from rat, dorsal root ganglia (DRG), cellular expression, and functional analysis of a novel tetrodotoxin-sensitive peripheral sodium channel (PN), PN1. PN1 mRNA is expressed in many different tissues. Within the rat DRG, both the mRNA and PN1-like immunoreactivity are present in small and large neurons. The abundance of sodium channel mRNAs in rat DRG is rBI > PN1 >/= PN3 >>> rBIII by quantitative reverse transcription-polymerase chain reaction analysis. Data from reverse transcription-polymerase chain reaction and sequence analyses of human DRG and other human tissues suggest that rat PN1 is an ortholog of the human neuroendocrine channel. In Xenopus oocytes, PN1 exhibits kinetics that are similar to rBIIa sodium currents and is inhibited by tetrodotoxin with an IC50 of 4.3 +/- 0.92 nM. Unlike rBIIa, the inactivation kinetics of PN1 are not accelerated by the coexpression of the beta-subunits.
Asunto(s)
Ganglios Espinales/metabolismo , Neuronas/metabolismo , Neuropéptidos , Canales de Sodio/biosíntesis , Secuencia de Aminoácidos , Animales , Clonación Molecular , ADN Complementario , Humanos , Sustancias Macromoleculares , Potenciales de la Membrana/efectos de los fármacos , Datos de Secuencia Molecular , Canal de Sodio Activado por Voltaje NAV1.7 , Oocitos/fisiología , Especificidad de Órganos , Reacción en Cadena de la Polimerasa , ARN Mensajero/biosíntesis , Ratas , Canales de Sodio/química , Canales de Sodio/fisiología , Tetrodotoxina/farmacología , Transcripción Genética , Xenopus laevisRESUMEN
Some antioxidants, including butylated hydroxyanisole (BHA), tetrahydropapaveroline (THP), nordihydroguiauretic acid, and 10,11-dihydroxyaporphine (DHA), were found to be potent inhibitors of the production of tumor necrosis factor (TNF)-alpha, IL-1 beta, and IL-6 by human peripheral blood mononuclear cells (PBMC) stimulated by lipopolysaccharide (LPS) (IC50s in the low micromolar range). Inhibition of cytokine production was gene selective and not due to general effects on protein synthesis. Inhibition of cytokine production by PBMC was observed also when other inducers were used (staphylococci, silica, zymosan). Much higher concentrations of other antioxidants--including ascorbic acid, trolox, alpha-tocopherol, butylated hydroxytoluene, and the 5-lipoxygenase inhibitor zileuton--did not affect the production of these cytokines. The active compounds did not inhibit IL-1-induced production of IL-6 in fibroblasts, showing the cell selectivity of the effect. Antioxidant-mediated inhibition of cytokine production was correlated with low levels of the corresponding messenger RNAs. Nuclear run-on experiments showed that THP inhibited transcription of the IL-1 beta gene. THP decreased the concentration of the transcription factors NF-kappa B and AP-1 detected in nuclear extracts of PBMC cultured in the presence or absence of LPS. THP and DHA markedly decreased the levels of TNF-alpha and IL-1 beta in the circulation of mice following LPS injection. Thus antioxidants vary widely in potency as inhibitors of the activation of transcription factors and of the transcription of genes for pro-inflammatory cytokines. Coordinate inhibition of the transcription of genes for inflammatory cytokines could provide a strategy for therapy of diseases with inflammatory pathogenesis and for septic shock.
Asunto(s)
Antioxidantes/farmacología , Citocinas/biosíntesis , Leucocitos Mononucleares/inmunología , Secuencia de Bases , Células Cultivadas , Ensayo de Inmunoadsorción Enzimática , Humanos , Interleucina-1/biosíntesis , Interleucina-6/biosíntesis , Leucocitos Mononucleares/efectos de los fármacos , Datos de Secuencia Molecular , ARN Mensajero/efectos de los fármacos , Factores de Transcripción/efectos de los fármacos , Transcripción Genética/efectos de los fármacos , Factor de Necrosis Tumoral alfa/biosíntesisRESUMEN
Human Langerhans cells (LC) were isolated from epidermal cell preparations by panning with mouse anti-CD1 monoclonal antibody. RNA was prepared and probed for the presence of mRNAs for various cytokines using radiolabeled cDNAs. After stimulation with phorbol myristate acetate LC express RNA for interleukin 1 alpha (IL-1 alpha) and interleukin 1 beta (IL-1 beta) and produce proteins but do not secrete them at detectable levels. LC-associated IL-1, particularly IL-1 alpha, may play a role in antigen presentation. PMA did not induce IL-6 expression in LC. The addition of lipopolysaccharide, a muramyl dipeptide analog, ionomycin, IL-1 alpha, tumor necrosis factor-alpha, insulin-like growth factor-1 or IL-6 did not induce IL-1 mRNA in LC. UVB augmented IL-1 beta mRNA expression. Glucocorticoids did not detectably affect IL-1 alpha or IL-1 beta mRNA levels following PMA induction, however, staurosporin inhibited IL-1 beta mRNA synthesis. Thus the inducers and regulators of IL-1 formation in human LC and monocytes are not identical.
Asunto(s)
Interleucina-1/biosíntesis , Células de Langerhans/inmunología , ARN Mensajero/metabolismo , Acetilmuramil-Alanil-Isoglutamina/farmacología , Expresión Génica , Humanos , Técnicas In Vitro , Interleucina-1/genética , Interleucina-1/metabolismo , Ionomicina/farmacología , Células de Langerhans/efectos de los fármacos , Células de Langerhans/metabolismo , Lipopolisacáridos/farmacología , ARN Mensajero/genética , Acetato de Tetradecanoilforbol/farmacologíaRESUMEN
Interleukin-1 (IL-1) and transforming growth factor alpha (TGF alpha) mRNA expression was analyzed in cultured normal human keratinocytes. Keratinocytes constititively express IL-1 mRNA when cultured in keratinocyte growth medium but not in Dulbecco's minimal essential medium containing fetal bovine serum, in which the cells differentiate. The predominant form of IL-1 expressed by keratinocytes is IL-1 alpha. Addition of IL-1 alpha to keratinocytes increased IL-1 alpha and TGF alpha mRNA expression in a dose-dependent manner. TGF alpha induced a similar increase in IL-1 alpha and TGF alpha mRNA in keratinocytes. Hydrocortisone decreased the expression of both IL-1 alpha and TGF alpha mRNA in keratinocytes. These findings document an autocrine mechanism by which IL-1 alpha and TGF alpha can stimulate the proliferation of keratinocytes in the skin. It is proposed that this autocrine loop may be hyperactive in psoriasis. Antagonism of the effects of this autocrine loop may be one of the mechanisms by which glucocorticoids exert clinically useful effects in psoriasis and other diseases of the skin.
Asunto(s)
Glucocorticoides/farmacología , Interleucina-1/biosíntesis , Queratinocitos/metabolismo , Factor de Crecimiento Transformador alfa/biosíntesis , Células Cultivadas , Citocinas/farmacología , Antígenos HLA-DR/genética , Humanos , Interferón gamma/farmacología , Interleucina-1/genética , Interleucina-1/farmacología , Queratinocitos/efectos de los fármacos , ARN Mensajero/análisis , ARN Mensajero/biosíntesis , Factor de Crecimiento Transformador alfa/genética , Factor de Crecimiento Transformador alfa/farmacologíaRESUMEN
In this study 184 lactose-fermenting Salmonella strains, collected in the National Salmonella Centre from the northern and central parts of Ponad were examined. Epidemiological, serological and biochemical investigations were carried out. Apart from this, chemotherapeutic resistance and male-phage sensitivity were determined. Most of strains belonged to S. agona serotype (S. typhimurium and S. oranienburg were also presented) which apart from the lactose-fermenting ability retained all the remaining biochemical features typical of Salmonella bacilli, were male-phage M13 resistant and showed a high resistance to a wide spectrum of chemotherapeutics. In order to establish the way of the acquiring lac+ property by Salmonella bacilli P22 phage transduction and conjugation experiments, with E. coli F'lac and Hfr H as donors, were performed. S. agona lac- strains were shown to acquire the lactose-fermenting ability by mating with E. coli.