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P Biagini

Publications and source records attributed to P Biagini.

At least 37 records · Page 2Linked to original sources
PubMed2000

Complete sequence determination and genetic analysis of Banna virus and Kadipiro virus: proposal for assignment to a new genus (Seadornavirus) within the family Reoviridae.

Arboviruses with genomes composed of 12 segments of double-stranded (ds) RNA have previously been classified as members or probable members of the genus Coltivirus within the family REOVIRIDAE: A number of these viruses have been isolated in North America and Europe and are serologically and genetically related to Colorado tick fever virus, the Coltivirus type species. These isolates constitute subgroup A of the coltiviruses. The complete genome sequences are now presented of two Asian arboviruses, Kadipiro virus (KDV) and Banna virus (BAV), which are currently classified as subgroup B coltiviruses. Analysis of the viral protein sequences shows that all of the BAV genome segments have cognate genes in KDV. The functions of several of these proteins were also indicated by this analysis. Proteins with dsRNA-binding domains or with significant similarities to polymerases, methyltransferases, NTPases or protein kinases were identified. Comparisons of amino acid sequences of the conserved polymerase protein have shown that BAV and KDV are only very distantly related to the subgroup A coltiviruses. These data demonstrate a requirement for the subgroup B viruses to be reassigned to a separate new genus, for which the name Seadornavirus is proposed.

Animals↗
PubMed1999

GBV-C/hepatitis G virus (HGV) RNA load in immunodeficient individuals and in immunocompetent individuals.

The aim of this study was to establish the mean plasma GBV-C/hepatitis G virus (HGV) RNA load in groups of GBV-C/HGV-infected individuals with varied immune status and to determine the most frequent patterns of evolution of the plasma GBV-C/HGV RNA load over time during the natural history of infection. The mean plasma GBV-C/HGV RNA load observed was, from the lowest to the highest: 5.21 log in immunodepressed multiply-transfused patients, 6.45 log in HIV-positive individuals, 6.66 log in immunocompetent multiply-transfused patients, and 6.71 log in blood donors. The difference was significant between the four groups (P < 0.0001). The most frequent pattern of evolution of the plasma GBV-C/HGV RNA load was as follows: after the primary GBV-C/HGV infection, the viral load was elevated from the onset; then, a high, persistent and relatively steady viral RNA level was the rule; and when it occurred, the loss of viremia was not preceded by a decrease before recovery from GBV-C/HGV infection.

Adolescent↗
PubMed1999

Screening for HBV, HCV and HIV genomes in blood donations: shortcomings of pooling revealed by a multicentre study simulating real-time testing.

This study was undertaken in order to determine whether screening of viremic blood donations by testing of pooled donor samples could constitute a technically feasible transfusional safety measure. A pilot study of real-time simulation, on a day-to-day basis, of screening of three viral genomes (hepatitis B virus (HBV), hepatitis C virus (HCV) and human immunodeficiency virus (HIV)) was conducted by five French Blood Centers on plasma samples collected from blood donors and studied within undiluted samples and within sample pools of various sizes. This study was carried out within time conditions compatible with the release of platelets. For the detection of HCV and HIV genomes, the five laboratories achieved a sensitivity that decreased with the size of the sample pool. Four were successful in detecting all undiluted samples. In the 1/10 diluted samples, four failed to detect one HIV or HCV sample. In the 1/100 diluted samples, all laboratories failed to detect one or more HIV or HCV samples. For HBV genome, no participating laboratories detected all of the samples of the panel, even undiluted samples, and the sample pooling considerably affected sensitivity. The improvement and standardization of assays needs to be attained, and training of laboratories appears to be a step crucial for routine screening of viral genomes in blood donations.

Blood↗
PubMed1999

The inhibitory effect of dexamethasone on lymphocyte adhesion molecule expression and intercellular aggregation is not mediated by lipocortin 1.

Glucocorticoids exert their anti-inflammatory activity through multiple pathways which include the inhibition of cell adhesion events. The glucocorticoid-induced protein lipocortin 1 (LC1) has reported anti-inflammatory properties and has been proposed as a putative mediator of the anti-inflammatory effects of glucocorticoids. The role of LC1 in mediating the glucocorticoid inhibition of lymphocyte adhesion and cell adhesion molecule (CAM) expression was investigated in vitro using a microaggregation assay, flow cytometry and confocal microscopy. Lymphocytes stimulated for 96 h with plastic-bound OKT3 antibody showed significant increases in LFA-1 and CD2 expression. Dexamethasone (DEX; 10(-6) M) inhibited this increase but the neutralizing anti-LC1 MoAb 1A (5 microg/ml) failed to reverse the DEX effect; neither was purified human LC1 (50 x 10(-9) M) able to inhibit CAM expression. The biological activity of the LC1 was confirmed by its ability to suppress monocyte phagocytosis and respiratory burst in response to bovine serum albumin (BSA)-anti-BSA complexes. OKT3 stimulation of cultured mononuclear cells resulted in intercellular aggregation, scored microscopically using a visual index. This aggregation was completely reversed by 10-6 M DEX but unaffected by LC1 (50 x 10(-9) M). Significant intracellular expression of lymphocyte LC1 was observed using the anti-LC1 MoAb 1B in saponin-permeabilized cells. Distribution of LC1 had a diffuse, cytoplasmic pattern. LC1 expression was reduced following 3 h treatment with 10(-6) M DEX. These findings indicate that the DEX effects on lymphocyte adhesion and CAM expression are not mediated by LC1. Thus the reported in vivo effects of LC1 on leucocyte adhesion and transmigration probably occur through functional/conformation changes of surface CAM, rather than by alteration in expression.

Annexin A1↗
PubMed1999

Prevalence of GB virus type C/hepatitis G virus RNA and anti-E2 among blood donors in Southeastern France.

BACKGROUND: The purpose of the study was to analyze serologic and molecular markers of the GB virus type C/hepatitis G virus (GBV-C/HGV) infection in voluntary blood donors from Southeastern France. STUDY DESIGN AND METHODS: Sera were tested for the presence of GBV-C/HGV RNA by reverse transcriptase-polymerase chain reaction and that of antibodies to the GBV-C/HGV E2 (anti-E2) antigen by an enzyme-linked immunosorbent assay. A first cohort (1660 blood donors) was tested prospectively and a second cohort (238 samples with hepatitis markers) was tested retrospectively. Donors in the prospective study were questioned for possible risk factors of virus transmission. Amplification products were sequenced and subjected to phylogenetic analysis. RESULTS: Approximately 2.6 percent of individuals accepted for blood donation and 15.4 percent with positive hepatitis C virus serologic tests carried GBV-C/HGV RNA. Anti-E2 was detected in these two populations in approximately 12 percent and 48 percent of donors, respectively. Moderate relative risks were found only in tattooed or pierced individuals (1.82) and health care workers (2.45). Almost all strains were located in the same phylogenetic branch as HGV Group 2. CONCLUSION: Though a large proportion of the donors tested have been in contact with GBV-C/HGV, no elevated relative risk of infection was identified. The phylogenetic distribution of viral strains suggests that the infection is endemic in this population.

Adolescent↗
PubMed1999

Soluble CD30 in early rheumatoid arthritis as a predictor of good response to second-line therapy.

OBJECTIVE: To evaluate whether serum levels of the soluble form of CD30 (sCD30) correlate with disease activity in early rheumatoid arthritis (RA) and may have prognostic value in predicting the response to disease-modifying anti-rheumatic drugs (DMARDs). METHODS: The levels of sCD30 and C-reactive protein (CRP) were measured in the serum of 14 untreated subjects with early RA, before and during treatment with hydroxychloroquine, for a follow-up period of 8 months. At the end of the study, patients were also evaluated for their response to DMARDs. RESULTS: An inverse correlation between sCD30 and CRP serum values was demonstrated at baseline, but not during the follow-up. Patients who responded to DMARD therapy had higher sCD30 basal levels than non-responders. CONCLUSIONS: The evaluation of sCD30 serum levels in early RA may reflect the attempt by CD30+ T cells to downmodulate inflammation and may be a useful marker to predict a good response to DMARDs.

Adult↗
PubMed1999

Determination and phylogenetic analysis of partial sequences from TT virus isolates.

Sera from French in-patients were tested for the presence of the TT virus (TTV) genome using PCR and degenerate primers located in ORF1. Thirty-six sequences were determined and compared with those deposited in databases, revealing a high degree of genetic variability between TTV isolates (up to 47% for amino acid sequences). Phylogenetic analysis demonstrated the existence of three main groups corresponding to the previously described genotypes 1 and 2 and to a new genotype 3. Isolates could be assigned to distinct genotypes if their genetic distance was > 27%. No comparable genetic criteria were found for the definition of sub-types in the region studied. A 15-31 month follow-up of three haemodialysis patients proved the existence of chronic infection by TTV. In one patient, two strains belonging to different genotypes were detected at the same time. Sequences of both ORF1 and ORF2 remained unchanged for a given strain during the follow-up.

Amino Acid Sequence↗
PubMed1999

TT virus infection in French hemodialysis patients: study of prevalence and risk factors.

The TT virus (TTV) is a recently discovered DNA virus which was first identified in patients with non-A to -G hepatitis following blood transfusion. In this study, we tested 150 attendees of two hemodialysis (HD) units of the public hospitals of Marseilles, France, for the presence of TTV genome by using a PCR-based methodology. The overall prevalence of TTV viremia was 28% (compared to 5.3% in blood donors from the same region). We demonstrated the existence of chronic infections and superinfections by strains belonging to different genotypes. The prevalence of infection was higher in patients originating from Africa, in patients with previous blood transfusion or organ transplantation, in patients with antibody to hepatitis B core antigen, and in those with diabetes mellitus. A high prevalence of TTV infection (50%) was also observed in a population of patients with diabetes mellitus but without renal disease. No significant relationship was found between TTV viremia and hepatitis C virus or GB virus C, transaminases, age, sex, and duration of HD treatment. The PCR amplification products (located in open reading frame 1 of the TTV genome) were sequenced. These genomic sequences were submitted to phylogenetic analysis by using the Jukes-Cantor algorithm for distance determination and the neighbor-joining method for tree building. In several instances, sequences from viruses isolated in a HD unit were grouped in the same phylogenetic cluster. These results together with the different distribution of cases in the two HD units suggest there is viral transmission within each.

Adult↗
PubMed1997

The human gastrin/cholecystokinin receptors: type B and type C expression in colonic tumors and cell lines.

The CCK-type B receptors are recognized by gastrin, which is known to be possibly involved in the development of gastro-intestinal cancers; alternate splicing of exon 4 of the human CCK-B receptor gene gives 2 different mRNA isoforms, the exact significance of which still remains to be elucidated. The recently described CCK-type C receptors recognize gastrin but do not discriminate between mature and immature forms of the hormone. A series of healthy and tumoral colon samples, the associated hepatic metastases and four colonic cell lines were examined for gene expression of the 2 isoforms of the CCK-B receptor and the CCK-C receptor using reverse transcription-polymerase chain reaction. Gastrin mRNA expression was also investigated. The short isoform of the CCK-B was detected in 80% of the normal colon tissues, 76.5% of the colon tumors, 100% of the metastasis samples and 75% of the colonic cell lines; whereas the long isoform, which is presumably more strongly activated by gastrin, was expressed in 50% of the normal colon samples, 23% of the colon tumors, 43% of the hepatic metastases and 1 cell line (Sk-Co15). However, although CCK-C transcript was detected in 100% of the tumors tested and gastrin mRNA in 86.5%, only 16.5% also expressed the long isoform of the CCK-B receptor. The gastrin/CCK-B receptor might therefore be involved in an hypothetic autocrine proliferative loop only in some colonic tumors, and the receptor mainly involved in this loop may well be the CCK-C receptor, since its mRNA is expressed as often as gastrin mRNA in tumors and cell lines.

Colonic Neoplasms↗
PubMed1997

Evaluation of four PCR systems amplifying different genomic regions for molecular diagnosis of GB virus C infections.

Diagnosis of GB virus C (GBV-C) infection is based on RT-PCR methodology that detects genomic viral RNA. Four sets of primers located in different genomic regions were compared. These primers were used to amplify a reference panel of sera used by the French blood banks, including five positive sera, five negative sera and 10-fold serial dilutions of one positive serum. Three sets of primers located in the 5'UTR, NS3 and NS5a genomic regions gave comparable results with undiluted sera. When diluted sera were tested, the most sensitive protocol was that using a set of primers and a probe selected within the 5'UTR, together with a colorimetric detection based on DNA enzyme immunoassay.

Evaluation Studies as Topic↗
PubMed1997

GEMHEP multicenter quality control study of PCR detection of GB virus C/hepatitis G virus RNA in serum.

PCR is, to date, the only available tool for the detection of GB virus C (GBV-C) and hepatitis G virus (HGV) RNAs. Twenty-two French laboratories participated in a quality control study to assess the sensitivity and specificity of their procedures. The panel included 13 positive controls and 7 negative controls. The laboratories used either in-house PCR techniques adapted from the literature or partly standardized commercial tests. Three laboratories performed faultlessly with the entire panel. Most laboratories had excellent specificity (100% in 20 of 22 laboratories). Sensitivity was acceptable (85 to 100%) in 15 centers and insufficient (38 to 77%) in 7. As with nonstandardized in-house PCR, the commercial assays gave discrepant performances in different laboratories. These results suggest that laboratories willing to use PCR for detection of GBV-C/HGV RNA for research or diagnostic purposes should participate in multicenter quality control trials.

Flaviviridae↗
PubMed1996

Gastrointestinal hormone mRNA expression in human colonic adenocarcinomas, hepatic metastases and cell lines.

Aims-(1) To investigate the expression of the four main hormones of the digestive tract by performing reverse transcription polymerase chain reaction (RT-PCR) on a series of samples, comprising tumoral and healthy colonic tissues, hepatic metastases and colonic cell line samples; and (2) to study the patterns of labelling obtained with serological and morphological markers.Methods-After extraction and reverse transcription, gastrin, somatostatin, cholecystokinin (CCK) and transforming growth factor alpha (TGFalpha) mRNAs were detected by PCR and nested PCR using specific primers. The corresponding proteins were detected by immunohistochemistry.Results-The cell lines expressed all four mRNAs. Gastrin mRNA was present in most tumoral and metastatic samples, while the somatostatin transcript was detected in all samples and was frequently overexpressed in the normal colon. TGFalpha mRNA was expressed systematically in tumours of the right and transverse colon, but not in those located in the left colon; the expression of CCK mRNA was systematically absent in the left colon.Conclusions-The data presented here shed some light on the transcriptional events involved in the production of the various hormones present in the gastrointestinal tract, in both healthy and tumoral tissues. The various mRNAs expressed in cell lines are therefore not systematically expressed in the human pathology.

Journal Article↗
PubMed1996

Is hepatitis C virus-RNA detection by nested polymerase chain reaction clinically relevant in hemodialysis patients?

We have prospectively studied in hemodialysis (HD) patients the evolution of hepatitis C virus (HCV) viremia and the putative relationships between the viremia and the biological markers of liver disease. For each of 22 HD patients having detectable antibodies to HCV (anti-HCV+), we looked four times for serum HCV-RNA by nested PCR (N-PCR), in April and November 1992, November 1993 and May 1994. We checked the transaminases (Trans) and the gamma glutamyl transpeptidase (gamma(GT)) levels on the same day as blood tests for the N-PCR. Abnormal Trans or gamma(GT)++ values were considered if they exceeded the upper limit of the normal level for our laboratory. Fifteen patients (68%) were intermittently N-PCR positive (N-PCR+): 3 patients were N-PCR+ at three determinations, 7 were N-PCR+ at two determinations and 5 only one time. Two patients (9%) were always N-PCR+ and five (23%) always negative. No correlation between an abnormal value of either Trans or gamma(GT) and viremia was evidenced at successive determinations. In conclusion, the majority (68%) of the anti-HCV+ patients had intermittent HCV N-PCR+. Among the anti-HCV+ patients, 77% were viremic. Since HCV viremia is often transitory and since there is no correlation between N-PCR positivity and the increase in Trans or gamma(GT) activities, HCV-RNA detection by N-PCR is probably not clinically relevant in anti-HCV+ HD patients.

Alanine Transaminase↗
PubMed1995

High levels of the soluble form of CD30 molecule in rheumatoid arthritis (RA) are expression of CD30+ T cell involvement in the inflamed joints.

The CD30 is a surface molecule expressed by Th2-type lymphokine-producing T cells upon activation. CD30-expressing activated T cells release a soluble form of the molecule, which can be detectable both in vitro and in vivo. In the present study, high levels of soluble CD30 were found in peripheral blood and synovial fluid from patients with RA. However, CD30+ CD3+ cells, either CD4+ or CD8+, were significantly present in synovial fluid, but not in peripheral blood, of RA patients. Serum values of soluble CD30 were higher in active than inactive RA patients and directly correlated with rheumatoid factor serum titres. These data strongly support an involvement of CD30+ T cells in the immune processes of rheumatoid synovitis, and may suggest a relationship between Th2-type cytokine-secreting T cells and the pathological response in RA.

Adult↗
PubMed1994

Detection of gastrin mRNA in paraffin-embedded samples of normal antral mucosae using polymerase chain reaction technique.

Gastrin, a peptide hormone produced by the G cells of the gastric antrum, plays a major role in the regulation of digestive mucosal growth. Although some light has been shed on the peptidic aspects of this hormone's mode of action and the co-regulatory activity in which it is involved along with the other gastrointestinal hormones, little is known at present about the modes of expression of its mRNA at the tissue level. A few attempts have been made so far to detect the transcript, mostly using molecular hybridization techniques. Here it was proposed to detect gastrin mRNA using a RT-PCR technique on a series of paraffin-embedded samples of normal human antrum processed with various fixatives commonly used in histology. The transcript was detectable in all the 7-microns sections of the samples treated with either formalin or Carnoy's solution, whereas Bouin's solution, which is also used as a fixative in histology, was found to have inhibitory effects on the method described here.

Acetates↗
PubMed1993

Detection of hepatitis C infection by polymerase chain reaction among hemodialysis patients.

One hundred forty-five patients on regular hemodialysis (HD) at our institution were evaluated for the presence of hepatitis C virus (HCV) infection. Forty-three patients (29%) were found to have detectable antibodies to HCV using second-generation enzyme-linked immunosorbent and recombinant immunoblot assays. Forty positive patients (anti-HCV+) and 10 negative patients (anti-HCV-) were tested for direct detection of the HCV genome by the polymerase chain reaction (PCR). Twenty-one anti-HCV+ patients (52%) had detectable RNA HCV in plasma (PCR+). No anti-HCV- patient had viremia. In addition, we compared the 43 anti-HCV+ patients with the 102 anti-HCV- patients for duration of HD, history of blood transfusion, serologic markers of hepatitis B virus, and acute and chronic liver disease. On retrospective univariate analysis, statistically significant associations with anti-HCV+ were duration of HD (P = 0.0001), blood transfusions (P = 0.0005), co-infection with hepatitis B virus (P = 0.01), and acute and chronic liver disease (P = 0.06 and 0.01, respectively). Three significant variables (duration of HD, chronic hepatitis, and blood transfusions) of the multivariate analysis permit the classification of 65% of anti-HCV+ patients and 81% of anti-HCV- patients. In the anti-HCV+ group, when the same parameters were compared in PCR+ or PCR- patients, no statistical difference appeared. These results reveal that 52% of anti-HCV+ HD patients have HCV infection. The clinical consequences of HCV infection in that population are not characterized since no difference has been documented between PCR+ and PCR- results.

Adolescent↗
PubMed1993

[HLA-DRB1 and HLA-DQB1 polymorphism in Algerians from Algiers].

The polymorphism of HLA-DRB1 and HLA-DQB1 genes in 100 unrelated Algerians from Alger was investigated using PCR amplification and oligonucleotide typing. Compared to western Europeans, this population shows a higher haplotypic frequency of HLA DRB1*03-DQB1*0201 (21.5%) and a lower haplotypic frequency of DRB1*0101-DQB1*0501 (2%). Two unexpected haplotypes are observed: DRB1*07-DQB1*0301 and DRB1*0406-DQB1*0402. DRB1*0402 is the most common subtype in the DRB1*04 group. Furthermore, we detected a rare DQB1*0305 allele, only found in a Sardinian subject until today.

Algeria↗