Novel fluoronucleoside analog NCC inhibits lamivudine-resistant hepatitis B virus in a hepatocyte model

ABSTRACT Antiviral drug resistance is the most important factor contributing to treatment failure using nucleos(t)ide analogs such as lamivudine for chronic infection with hepatitis B virus (HBV). Development of a system supporting efficient replication of clinically resistant HBV strains is imperative, and new antiviral drugs are needed urgently to prevent selection of drug-resistant HBV mutants. A novel fluorinated cytidine analog, NCC (N-cyclopropyl-4′-azido-2′-deoxy-2′-fluoro-β-d-cytidine), was recently shown to strongly inhibit human HBV in vitro and in vivo. This study was designed to evaluate the antiviral activity of NCC against lamivudine-resistant HBV. We generated a stable cell line encoding the major pattern of lamivudine-resistant mutations rtL180M/M204V and designated it "HepG2.RL1". Immuno-transmission electron microscopic examination and enzyme-linked immunosorbent assay were used to detect secretion of HBV-specific particles and antigens. Quantification of extracellular DNA and intracellular DNA of HepG2.RL1 cells by quantitative real-time polymerase chain reaction revealed >625-fold and >5556-fold increases in the 50% inhibitory concentration of lamivudine, respectively, compared with that for the wild-type virus. The results showed that NCC inhibited DNA replication and HBeAg production in wild-type or lamivudine-resistant HBV in a dose-dependent manner. In conclusion, screening for antiviral compounds active against lamivudine-resistant HBV can be carried out with relative ease using hepG2.RL1 cells. NCC is a potential antiviral agent against wild-type HBV and clinical lamivudine-resistant HBV and deserves evaluation for the treatment of HBV infection.

Cytidine-phosphate-guanosine oligodeoxynucleotides in combination with CD40 ligand decrease periodontal inflammation and alveolar bone loss in a TLR9-independent manner

Abstract Local administration of toll-like receptor 9 (TLR9), agonist cytidine-phosphate-guanosine oligodeoxynucleotide (CpG ODNs), and CD40 ligand (CD40L) can decrease ligature-induced periodontal inflammation and bone loss in wild type (WT) mouse. Objective: This study aimed to explore whether such effect is dependent on TLR9 signaling. Material and Methods: Purified spleen B cells isolated from WT C57BL/6J mice and TLR9 knockout (KO) mice were cultured for 48 hours under the following conditions: CD40L, CpG+CD40L, CpG at low, medium and high doses. We determined B cell numbers using a hemocytometer at 24 h and 48 h. Percentages of CD1dhiCD5+ B cells were detected by flow cytometry. Interleukin-10 (IL-10) mRNA expression and protein secretion were measured by quantitative real-time polymerase chain reaction (qRT-PCR) and by ELISA, respectively. The silk ligature was tied around the maxillary second molars for 14 days, during which the CpG+CD40L mixture or PBS was injected into palatal gingiva on days 3, 6, and 9. Results: For both WT and TLR9 KO mice, CpG significantly induced B cell proliferation, increased IL-10 mRNA expression and protein secretion of IL-10 but reduced CD1dhiCD5+ B cells population; local injection of CpG+CD40L mixture significantly decreased alveolar bone loss and the number of TRAP-positive cells adjacent to the alveolar bone surface, and significantly increased the gingival mRNA expression of IL-10 and decreased RANKL and IFN-γ mRNA expression. Conclusions: These results indicated that CpG plus CD40L decreased periodontal inflammation and alveolar bone loss in a TLR9-independent manner in ligature-induced experimental periodontitis.

Neural compression-induced neuralgias: clinical evaluation of the effect of nucleotides associated with vitamin B12

The use of a combination of uridine triphosphate (UTP), cytidine monophosphate (CMP), and hydroxocobalamin was evaluated in a double-blind, randomized study in the treatment of neuralgia due to degenerative orthopedic alterations with neural compression. Following informed consent, 80 patients were randomized to a 30 day treatment period. The subjects received a thrice-daily oral treatment regimen of either the combination treatment (Group A: total daily dose of 9mg UTP, 15mg CMP, 6 mg hydroxocobalamin) or vitamin B12 alone (Group B: total daily dose of 6 mg hydroxocobalamin). Efficacy measures evaluated global patient condition from the perspective of the subject and the investigating physician pain ? measured by a visual-analog scale and functionality, using a patient-response questionnaire. The safety evaluation took into account physical evaluations and laboratory tests performed at each visit to the study center as well as the incidence and severity of adverse events. At the end of the 30-day treatment period, there were reductions in the pain scale scores in both groups, however there was a significantly larger reduction in the scores of the Group A patients. The Patient Global Evaluation scores improved in both groups but showed greater improvement in Group A, while the Physician Global Evaluation improved significantly only in Group A. A similar finding was observed in the scores of the Patient Functionality Questionnaire. Based on the findings of this clinical trial, we conclude that the combination of UTP, CMP, and vitamin B12 has a positive effect on pain and functionality improvement in the treatment of degenerative orthopedic alterations with neural compression, in the study population evaluated.

Leucemía mieloide aguda en niños del Hospital Universitario de Caracas (Período 1979-1989) / Acute myeloid leukemia in children at the University Hospital of Caracas (period 1979-1989)

En el Hospital Universitario de Caracas 52 nuevos casos de Laucemia Mieloblástica aguda (LMA) fueron tratados en dos series consecutivas entre 1979-1989. Concomitantemente se intentó correlacionar los hallazgos clínicos y de laboratorio al ingreso, y la respuesta al tratamiento, con los subtipos morfológicos (FAB) de LMA. Serie I (1979-1985): comprendió 37 niños que recibieron principalmente la terapia de inducción con Citosina Arabinosa 100 mg/m2/día, en una infusión continua por 7 días, además de Daunomicina 45 mg/m2/día, en los 3 primeros días del tratamiento. La serie II incluyó solo 15 pacientes tratados en igual forma, excepto por la Citosina Arabinosa que se administró durante 10 días. Los pacientes que alcanzaron remisión en ambas series recibieron luego 5 ciclos con el esquema de COAP como terapia de consolidación. Posteriormente, fueron a un tratamiento de mantenimiento semanal con 6-Thioguanima por 4 días más Citosina Arabinosa el 5to. día durante 24 meses en remisión contínua. el tratamineto de inducción se realizó en 44 niños, dado que 7 murieron durante la fase de inducción en aplasia y otro caso se descartó por Síndrome de Down. La remisión completa fue de 64 por ciento (21/33) en la Serie I y de 36 por ciento (4/11) en la Serie II; observandose en ambas series un 42 por ciento de LMA con un componente monocítico, la mayoría del tipo M4 y 80 por ciento (20/25) de los casos que alcanzaron remisión, presentaban diferenciación mieloide FAB M1-M4. La duración de la remisión fué corta, lo que sugiere fallas en el tratamiento citotócico recayendo el 60 por ciento en los primeros 6 meses. La sobrevida libre de enfermedad fue menor de 20 por ciento al año y de sólo 6 por ciento a los 30 meses, sin diferencias estadísticas significativas en las 2 Series. Se estima que la problemática asistencial crónica de nuestro hospital pudo haber influido en la alta tasa de mortalidad temprana. Esta es la primera casuística de niños con LMA reportada en Venezuela