RESUMEN
BACKGROUND: Hepatitis C virus and interferon treatment have been associated with retinopathy. Baseline and ongoing assessment by ophthalmologists have therefore been advocated in previous studies. Our experience suggests that the incidence is low, with no or negligible impact of pegylated interferon alpha on actual visual function. This study was conducted to determine whether ophthalmic assessment is necessary in such patients. METHODS: The study was a prospective case series of 52 patients (104 eyes). Visual acuity, contrast sensitivity, colour vision, visual field by perimetry and fundal assessment were measured at baseline and at 3 and 6 months post commencement of interferon alpha treatment. RESULTS: Forty-two men and ten women were followed. No patients reported any subjective visual symptoms. The mean changes in right and left logarithmic minimal angle resolution (LogMAR) visual acuity were negligible between baseline and 6 months (0.05 (SD 0.13) and 0.10 (SD 0.12), respectively). Mean changes in contrast sensitivity and colour vision were also negligible. Of all eyes monitored by serial perimetry for the full follow-up period and deemed to have reliable tests, none developed visual field defects. One patient appeared to develop nasal field defects within 3 months of commencing treatment but failed to attend for repeat testing. No patients developed optic disc changes or permanent fundal changes over the follow-up period. CONCLUSION: In contrast to previous studies in America and south-east Asia, our findings based on a UK cohort suggest that routine ophthalmic screening is not essential for patients with hepatitis C treated with pegylated interferon alpha who have no subjective visual complaints.
Asunto(s)
Antivirales/farmacología , Hepatitis C Crónica/tratamiento farmacológico , Interferón-alfa/farmacología , Polietilenglicoles/farmacología , Visión Ocular/efectos de los fármacos , Percepción Visual/efectos de los fármacos , Adulto , Antivirales/uso terapéutico , Percepción de Color/efectos de los fármacos , Sensibilidad de Contraste/efectos de los fármacos , Femenino , Estudios de Seguimiento , Hepatitis C Crónica/fisiopatología , Hepatitis C Crónica/psicología , Humanos , Interferón alfa-2 , Interferón-alfa/uso terapéutico , Masculino , Persona de Mediana Edad , Polietilenglicoles/uso terapéutico , Estudios Prospectivos , Proteínas Recombinantes , Agudeza Visual/efectos de los fármacosRESUMEN
Cotton, the major cash crop in Pakistan, suffers 30% losses to cotton leaf curl disease, caused by the geminivirus, cotton leaf curl virus DNA A, plus a satellite component, DNA beta responsible for symptom development with plants failing to produce cotton bolls. We constructed transgenic tobacco expressing sense and antisense RNAs representing: [i] the 5' half of the viral DNA replication gene, AC1, [ii] the 3' half of AC1, [iii] two overlapping genes, AC2, a transcription activator, and AC3, a replication enhancer. In contrast to controls, 25% of 72 transgenic tobacco lines tested showed heritable resistance [T(1) - T(3) generations]: symptom-free and no replication of DNA A or DNA beta even after 120 days of continuous exposure to viruliferous whiteflies. As geminiviral and transgene RNAs are not detected in resistant lines following infection, and selected uninfected resistant tobacco sense lines reveal double-stranded and small interfering RNAs, the most likely mechanism is via post-transcriptional gene silencing.
Asunto(s)
Geminiviridae/genética , Gossypium/virología , Nicotiana/virología , Enfermedades de las Plantas/virología , Interferencia de ARN , ARN Viral/genética , Replicación del ADN , Plantas Modificadas Genéticamente , Nicotiana/genética , Transgenes , Replicación ViralRESUMEN
We report the case histories of two patients treated in our unit for cervical radiculopathy by anterior cervical discectomy and BOP grafting. Both grafts disintegrated within 6 weeks of insertion resulting in increased neurological deficit from cervical cord compression. At reoperation fibres from the grafts were found to have separated and the larger fragments had extruded into the vertebral canal. No evidence of infection was seen, but a foreign body reaction was found in one case. Following graft removal the patients improved symptomatically although one was left with permanent mild biceps weakness.