A complex interaction between the Glucocorticoid Receptor (GR), C/EBPbeta, and other transcription factors activate the Alpha-1 Acid Glycoprotein (AGP) promoter in HTC(JZ-1) rat hepatoma culture cells. This effect is mediated by the so-called Steroid Responsive Unit (SRU) of the AGP promoter that contains several binding sites for C/EBP transcription factors, some of which overlap with the Glucocorticoid Responsive Element (GRE). Our in vivo footprinting experiments revealed that the GRE- and the C/EBP-binding sites were already occupied glucocorticoid dependently in HTC(JZ-1) cells 10 min after dexamethasone administration (10(-6) M).
View Article and Find Full Text PDFBacillus subtilis is the best-characterized member of the Gram-positive bacteria. Its genome of 4,214,810 base pairs comprises 4,100 protein-coding genes. Of these protein-coding genes, 53% are represented once, while a quarter of the genome corresponds to several gene families that have been greatly expanded by gene duplication, the largest family containing 77 putative ATP-binding transport proteins.
View Article and Find Full Text PDFA new hepatitis-associated RNA virus of the Flaviviridae family has been identified and named GB virus C/ hepatitis G virus (HGV). We carried out a case-control study to evaluate the association of HGV infection with hepatocellular carcinoma (HCC). We recruited 170 patients hospitalized for HCC (143 male and 27 female, mean age 64 years) and 306 patients hospitalized for nonliver diseases (controls) in Brescia, Italy.
View Article and Find Full Text PDFA 15 kb DNA fragment from the Bacillus subtilis chromosome between citB and ppsC has been sequenced, and new ORFs encoding putative enzymes involved in lipopolypeptide synthesis, which complete a partial operon previously reported, and a new set of enzymes responsible for lipid metabolism have been identified. From the analysis of DNA sequence homology of the fragment it was deduced that these new peptide synthetase genes are part of an operon for the biosynthesis of the fungicide fengycin.
View Article and Find Full Text PDFTo evaluate the role of estrogen receptor in the differentiation of cells of neural origin, we developed a molecular approach aimed at the identification of estrogen target genes by mRNA differential display PCR (ddPCR) in human neuroblastoma SK-ER3 cells. More than 3000 RNAs were examined, a few of which displayed a differential regulation pattern in response to 17beta-estradiol (E2). Sequence analysis of three differentially amplified ddPCR products showed homology with the growth-associated nuclear protein prothymosin-alpha (PTMA), the Bcl2-interacting protein Nip2, and one mRNA previously described by others in fetal human brain.
View Article and Find Full Text PDFFerritin is a protein of 24 subunits which assemble into a shell with 432 point symmetry. It can be denatured reversibly in acidic guanidine hydrochloride, with the formation of poorly populated renaturation intermediates. In order to increase the accumulation of intermediates and to study the mechanism of ferritin renaturation, we analysed variants of the human ferritin H-chain altered at the N-terminus (delta(1-13)), near the 4-fold axis (Leu-169 --> Arg), the 3-fold axis (Asp-131 --> Ile + Glu-134 --> Phe) or the 2-fold axis (Ile-85 --> Cys).
View Article and Find Full Text PDFWe have cloned and sequenced the nrd (nucleotide reductase) locus of Bacillus subtilis. The locus seems to be organized in an operon comprising four ORFs. The first three encode polypeptides highly similar to the product of the coding sequences characterizing the nrdEF operons of Enterobacteriaceae.
View Article and Find Full Text PDFA case of simultaneous infection with HIV and HCV characterized by a rapidly progressive clinical course was studied retrospectively over 3.5 years. Molecular analysis indicated interference between HIV and HCV and between HCV subtypes 1a and 1b.
View Article and Find Full Text PDFToxicol Appl Pharmacol
September 1996
SK-ER3 cells were recently demonstrated to represent a valuable model for the study of estrogen-inducible differentiation of neural cells in culture. This system may constitute an important tool also for the analysis of the effects of neurotoxic drugs. The present study demonstrates that short term exposure to Mn causes increased proliferation rate of SK-ER3 cells regardless of their differentiation.
View Article and Find Full Text PDFMicrobiology (Reading)
August 1996
The Bacillus subtilis mutS and mutL genes, involved in the DNA mismatch repair system, have been cloned and characterized. From sequence analysis the two genes appear to be organized in a single operon, located immediately downstream of the cotE gene (approximately 150 degrees on the genetic map). The deduced MutS protein is 49% identical to HexA and MutL is 46% identical to HexB of Streptococcus pneumoniae.
View Article and Find Full Text PDFThe aim of this work was to search for a simple and alternative approach to the currently used methodologies for the analysis of T-cell receptor repertoire diversity. To this end we studied whether the heteroduplex analysis could be adapted to study the clonality of the T-cell receptor beta chain (TCRBV). We therefore analyzed, by sequencing, the molecular characteristics of the V-D-J junctions of numerous TCRBV chains from a variety of patients and from normal individuals, and compared the results with those obtained with the heteroduplex analysis.
View Article and Find Full Text PDFAIDS Res Hum Retroviruses
December 1995
We describe the specific interaction between high-purity recombinant human immunodeficiency virus (HIV) type 1 p17 and human gamma interferon (hIFN-gamma) proteins. This interaction was found to be dose dependent and to involve conformational epitopes on both sides. Specificity was confirmed by competition ELISA, using monoclonal antibodies (MAbs) to hIFN-gamma as specific reagents.
View Article and Find Full Text PDFImmunological and genomic analysis of the "a" determinant was carried out in seven patients with concurrent HBsAg and anti-HBs, four of whom were immunized against hepatitis B virus at liver transplant, two with histologically characterized chronic hepatitis B virus infection, and one HBsAg healthy carrier. The immune reactivity of the HBsAg "a" determinant was evaluated by binding to specific monoclonal antibodies, and the corresponding genomic sequence was studied by differential hybridization in microtiter plates and nucleotide sequence analysis. A double mutation generating an amino acid change (glycine to lysine) at residue 145, able to impair recognition by monoclonal antibodies, was observed in the post-transplant serum from one patient.
View Article and Find Full Text PDFWe have examined the regulatory effects of interleukin 1 beta (IL-1 beta) on the activation of three different isoforms of the C/EBP family of transcription factors (alpha, beta and delta), in hepatocytes of normal and adrenalectomized (ADX) rats. C/EBP-beta and delta mRNA levels were enhanced by IL-1 beta, whereas that of C/EBP-alpha was not affected by treatment with this interleukin in both normal and adrenalectomized rats. The magnitude of the induction was strikingly higher for C/EBP delta in adrenalectomized animals, indicating a suppressive effect of corticosteroids in the IL-1 beta regulatory pathway.
View Article and Find Full Text PDFIn this work, we have studied the activity of a tetracycline modulatable trans-activator (tTA) generated by fusing the DNA binding domain of the tetracycline repressor to the trans-activation domain of the Herpes simplex virus protein 16 (HSV VP16) (plasmid pUHD15-1Neo). In the three different cell lines studied (HTC, rat hepatoma; T47D, human breast cancer; SK-N-BE, human neuroblastoma), the expression of the luciferase gene under the control of a tetracycline operator sequence (plasmid pUHC13-3) was used as a control of the incorporation and the functionality of the trans-activator. Clones selected from these cells responded in a time and dose-dependent manner to the withdrawal of tetracycline.
View Article and Find Full Text PDFEur J Clin Microbiol Infect Dis
July 1995
The performance and clinical relevance of a qualitative PCR-based assay for the detection of HIV-1 DNA sequences in peripheral blood mononuclear cells (PBMCs) was evaluated by two different laboratories. Four hundred and one samples were obtained from 397 individuals from different risk populations. All blood donors tested had negative results; positive signals were obtained from all infected patients.
View Article and Find Full Text PDFThe outB gene of Bacillus subtilis is involved in spore germination and outgrowth and is essential for growth. The OutB protein was obtained by expression in Escherichia coli and purified to apparent homogeneity. Here we report experiments showing that OutB is a NH3-dependent NAD synthetase, the enzyme that catalyzes the final reaction in the biosynthesis of NAD.
View Article and Find Full Text PDFThe direct detection of hepatitis C virus (HCV) RNA by PCR is widely used to determine the presence of circulating virions. The most relevant limit of this approach is the lack of quantitative information about the viral titer. We report a technique of competitive amplification allowing the estimation of HCV RNA copy number in biological samples.
View Article and Find Full Text PDFMicrobiology (Reading)
February 1995
The nucleotide sequence of 20 kb contiguous to the pksX locus of Bacillus subtilis was determined. Six ORFs were recognized, one of which extended for 13,341 nucleotides. Their predicted products have significant similarities to proteins with known functions involved in the synthesis of polypeptides and polyketides or in fatty acid metabolism.
View Article and Find Full Text PDFBackground: Little is known about the prevalence of serum hepatitis C virus (HCV) RNA in blood donors with HCV antibodies and persistently normal alanine aminotransferase (ALT) levels.
Study Design And Methods: Thirty-nine anti-HCV-positive donors with normal ALT on four determinations at 3-month intervals were further tested monthly for 6 months, and they had normal ALT values. The presence of HCV RNA was determined in these 39 donors.
The quality assurance system in clinical chemistry allows for the identification of errors and control actions to correct them. It is well known that laboratory errors can be classified as: pre-analytical, analytical and post-analytical. While pre-analytical and post-analytical errors are very difficult to identify, the analytical variability (both imprecision and inaccuracy) can be monitored with internal quality control (IQC) programs and external quality assessment (EQA) schemes.
View Article and Find Full Text PDFThis paper deals with the organization, the data processing and some of the results obtained in Italian external quality assessment (EQA) schemes for hormones, tumor markers and hepatitis B markers. The EQA for hormones and tumor markers includes up to sixteen analytes together with the participation, in 1990, of about 250 laboratories. Laboratory results were used to prepare periodic and end-of-period reports.
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