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1.
Invertebr Syst ; 382024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38744492

RESUMO

The pantropical genus Palaemonella Dana, 1852 (Caridea: Palaemonidae) currently includes 27 species of free-living and symbiotic marine shrimps. The monophyly of Palaemonella with respect to several closely related genera, however, has been questioned by recent analyses. We tested the monophyly of Palaemonella based on multigene phylogenetic analysis and the genus was revealed to be a paraphyletic assemblage by inclusion of species of the genera Eupontonia Bruce, 1971 and Vir Holthuis, 1952, and two genetic lineages of the western Atlantic Cuapetes americanus (Kingsley, 1878). We recognise one of the latter lineages as the previously described Periclimenes rhizophorae Lebour, 1949. Eupontonia and Vir are synonymised with Palaemonella . We also transfer Cuapetes americanus and Periclimenes rhizophorae to Palaemonella . Species previously assigned to Vir were revised; V. colemani Bruce, 2003, V. orientalis (Dana, 1852), V. philippinensis Bruce & Svoboda, 1984 and V. smiti Fransen & Holthuis, 2007 are regarded as valid species of Palaemonella ; Vir longidactylus Marin, 2008 is synonymised with P. smiti ; and the status of V. euphyllius Marin & Anker, 2005 remains unresolved. Palaemonella is currently regarded as a taxon with variable states of two main diagnostic characters, i.e. the plesiomorphic mandibular palp (fully reduced in P. americana ) and the hepatic tooth (fully reduced in former species of Vir and Eupontonia - evidently due to symbiotic modes of life). ZooBank: urn:lsid:zoobank.org:pub:7EEBC655-7EDE-4E46-BCB2-2A3BA16ED7DD.


Assuntos
Palaemonidae , Filogenia , Animais , Palaemonidae/classificação , Palaemonidae/genética , Especificidade da Espécie
2.
Lancet ; 389(10070): 709-717, 2017 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-28087069

RESUMO

BACKGROUND: miR-122 is an important host factor for hepatitis C virus (HCV) replication. The aim of this study was to assess the safety and tolerability, pharmacokinetics, and antiviral effect of a single dose of RG-101, a hepatocyte targeted N-acetylgalactosamine conjugated oligonucleotide that antagonises miR-122, in patients with chronic HCV infection with various genotypes. METHODS: In this randomised, double-blind, placebo-controlled, multicentre, phase 1B study, patients were randomly assigned to RG-101 or placebo (7:1). We enrolled men and postmenopausal or hysterectomised women (aged 18-65 years) with chronic HCV genotype 1, 3, or 4 infection diagnosed at least 24 weeks before screening who were either treatment naive to or relapsed after interferon-α based therapy. Patients with co-infection (hepatitis B virus or HIV infection), evidence of decompensated liver disease, or a history of hepatocellular carcinoma were excluded. Randomisation was done by an independent, unblinded, statistician using the SAS procedure Proc Plan. The first cohort received one subcutaneous injection of 2 mg/kg RG-101 or placebo; the second cohort received one subcutaneous injection of 4 mg/kg or placebo. Patients were followed up for 8 weeks (all patients) and up to 76 weeks (patients with no viral rebound and excluding those who were randomised to the placebo group) after randomisation. The primary objective was safety and tolerability of RG-101. This trial was registered with EudraCT, number 2013-002978-49. FINDINGS: Between June 4, 2014, and Oct 27, 2014, we enrolled 32 patients with chronic HCV genotype 1 (n=16), 3 (n=10), or 4 (n=6) infections. In the first cohort, 14 patients were randomly assigned to receive 2 mg/kg RG-101 and two patients were randomly assigned to receive placebo, and in the second cohort, 14 patients were randomly assigned to receive 4 mg/kg RG-101 and two patients were randomly assigned to receive placebo. Overall, 26 of the 28 patients dosed with RG-101 reported at least one treatment-related adverse event. At week 4, the median viral load reduction from baseline was 4·42 (IQR 3·23-5·00) and 5·07 (4·19-5·35) log10 IU/mL in patients dosed with 2 mg/kg RG-101 or 4 mg/kg RG-101. Three patients had undetectable HCV RNA levels 76 weeks after a single dose of RG-101. Viral rebound at or before week 12 was associated with the appearance of resistance associated substitutions in miR-122 binding regions in the 5' UTR of the HCV genome. INTERPRETATION: This study showed that one administration of 2 mg/kg or 4 mg/kg RG-101, a hepatocyte targeted N-acetylgalactosamine conjugated anti-miR-122 oligonucleotide, was well tolerated and resulted in substantial viral load reduction in all treated patients within 4 weeks, and sustained virological response in three patients for 76 weeks. FUNDING: Regulus Therapeutics, Inc.


Assuntos
Hepatite C Crônica/tratamento farmacológico , MicroRNAs/antagonistas & inibidores , MicroRNAs/uso terapêutico , Acetilgalactosamina , Estudos de Coortes , Método Duplo-Cego , Feminino , Humanos , Injeções Subcutâneas , Masculino , MicroRNAs/farmacocinética , Pessoa de Meia-Idade , Oligonucleotídeos , Carga Viral/efeitos dos fármacos
3.
Antimicrob Agents Chemother ; 59(1): 599-608, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25385103

RESUMO

Miravirsen is a ß-D-oxy-locked nucleic acid-modified phosphorothioate antisense oligonucleotide targeting the liver-specific microRNA-122 (miR-122). Miravirsen demonstrated antiviral activity against hepatitis C virus (HCV) genotype 1b replicons with a mean 50% effective concentration (EC50) of 0.67 µM. No cytotoxicity was observed up to the highest concentration tested (>320 µM) in different cell culture models, yielding a therapeutic index of ≥ 297. Combination studies of miravirsen with interferon α2b, ribavirin, and nonnucleoside (VX-222) and nucleoside (2'-methylcytidine) inhibitors of NS5B, NS5A (BMS-790052), or NS3 (telaprevir) indicated additive interactions. Miravirsen demonstrated broad antiviral activity when tested against HCV replicons resistant to NS3, NS5A, and NS5B inhibitors with less than 2-fold reductions in susceptibility. In serial passage studies, an A4C nucleotide change was observed in the HCV 5' untranslated region (UTR) from cells passaged in the presence of up to 20 µM (40-fold the miravirsen EC50 concentration) at day 72 of passage but not at earlier time points (up to 39 days of passage). Likewise, a C3U nucleotide change was observed in the HCV 5'UTR from subjects with viral rebound after the completion of therapy in a miravirsen phase 2 clinical trial. An HCV variant constructed to contain the A4C change was fully susceptible to miravirsen. A C3U HCV variant demonstrated overall reductions in susceptibility to miravirsen but was fully susceptible to all other anti-HCV agents tested. In summary, miravirsen has demonstrated broad antiviral activity and a relatively high genetic barrier to resistance. The identification of nucleotide changes associated with miravirsen resistance should help further elucidate the biology of miR-122 interactions with HCV. (The clinical trial study has been registered at ClinicalTrials.gov under registration no. NCT01200420).


Assuntos
Antivirais/farmacologia , Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/tratamento farmacológico , MicroRNAs/antagonistas & inibidores , Oligonucleotídeos/farmacologia , Regiões 5' não Traduzidas , Carbamatos/farmacologia , Cicloexanóis/farmacologia , Farmacorresistência Viral/efeitos dos fármacos , Quimioterapia Combinada , Hepacivirus/genética , Hepacivirus/isolamento & purificação , Hepatite C Crônica/virologia , Humanos , Imidazóis/farmacologia , Compostos Macrocíclicos/farmacologia , Terapia de Alvo Molecular/métodos , Mutação , Oligopeptídeos/farmacologia , Pirrolidinas , Quinolinas/farmacologia , Replicon/efeitos dos fármacos , Tiazóis/farmacologia , Tiofenos/farmacologia , Valina/análogos & derivados
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