No abstract

Hepatitis C virus-related chronic hepatitis may be associated with various immunological disorders. The aim of this study was to determine prospectively the prevalence of the clinical, biochemical and pathological immunological abnormalities in a series of 61 consecutive patients with chronic hepatitis C, compared with those in 61 age- and sex-matched control subjects without markers of hepatitis C virus and hepatitis B virus infections and with those in 61 patients with chronic hepatitis B. The following investigations were systematically performed before any treatment: detection of serum cryoglobulinemia and rheumatoid factor, detection of a large variety of serum anti-tissue antibodies, biopsy of labial salivary glands, ophthalmological examination, dosage of thyroid-stimulating hormone and in vivo capillary microscopy. Cryoglobulinemia was found in 36% of the hepatitis C virus patients, four of whom had dermatological and/or neurological manifestations of vasculitis, and rheumatoid factor was present in 70%. Serum anti-tissue antibodies were detected in 41% of cases, mostly antinuclear and anti-smooth muscle antibodies. Liver-kidney microsomal and antithyroid antibodies were rare. Salivary gland lesions were found in 49% of the patients: all had lymphocytic capillaritis, sometimes associated with lymphocytic sialadenitis resembling that of Sjögren's syndrome, but without features of sicca syndrome and Ro/SSA antibodies. Five percent of the patients had lichen planus. The prevalences of cryoglobulinemia, rheumatoid factor and anti-tissue antibodies were significantly higher than those in the control group and patients with chronic hepatitis B.(ABSTRACT TRUNCATED AT 250 WORDS)

Abstract. In cycling cells, the rDNAs are expressed from telophase to the end of G2 phase. The early resumption of rDNA transcription at telophase raises the question of the fate of the rDNA transcription machinery during mitosis. At the beginning of mitosis, rDNA transcription is arrested, and the rDNAs are clustered in specific chromosomal sites, the nucleolar organizer regions (NOR). In human cells, we demonstrate that the rDNA transcription machinery, as defined in vitro, is colocalized in some NORs and absent from others whatever the mitotic phase: RNA polymerase I and the RNA polymerase I transcription factors, upstream binding factor and promoter selectivity factor (as verified for TATA-binding protein and TATA-binding protein-associated factor for RNA polymerase I [110]), were colocalized in the same NORs. The RNA polymerase I complex was localized using two different antibodies recognizing the two largest subunits or only the third largest subunit, respectively. These two antibodies immunoprecipitated the RNA polymerase I complex in interphase cells as well as in mitotic cells. These results clearly indicated that the RNA polymerase I complex remained assembled during mitosis. In addition, RNA polymerase I and the transcription factors varied in the same proportions in the positive NORs, suggesting stoichiometric association of these components. The fact that the rDNA transcription machinery is not equally distributed among NORs most likely reflects the implication of the different NORs during the subsequent interphase. Indeed, we demonstrate that only positive NORs exhibit transcription activity at telophase and that the level of transcription activity is related to the amount of rDNA transcription machinery present in the NOR. We propose that assembly of rDNA transcription machinery preceding mitosis determines expression of the rDNAs at the beginning of the next cell cycle. Consequently, the association of rDNAs with the rDNA transcription machinery defines the "active" NORs and the level of activity at the transition telophase/interphase.

Drug-induced LABD was more severe than the spontaneous form, with lesions mimicking toxic epidermal necrolysis. Because LABD may be polymorphic and sometimes life threatening, DIF assay is recommended for all patients with Nikolsky sign and large erosions.