Production study of high specific activity NCA Re-186g by proton and deuteron cyclotron irradiation.

Very high specific activity (A(S)) (186g)Re could be produced by either proton or deuteron cyclotron irradiation on highly enriched (186)W target in no-carrier-added (NCA) form, leading to a A(S) very close to the theoretical carrier free (CF) value of 6.88GBqmicrog(-1). Thick target yields (TTYs), obtained irradiating both thick metal W targets of natural isotopic composition and highly enriched pressed powdered (186)W targets, were measured at different particles energies taking into account high accuracy and precision on both yield and beam energy. The measurement of radionuclidic purity of (186g)Re obtained activating highly enriched (186)W by both p and d beams were also carried out and accurately compared. The excitation function as thin-target yields (tty, i.e. proportional to the reaction cross-sections) and the integrated TTYs for all Re (A=181, 182, 183, 184, 186 and their metastable levels), W and Ta co-produced radionuclides will be presented elsewhere in deep details.

Elevated expression and polymorphisms of SOCS3 influence patient response to antiviral therapy in chronic hepatitis C.

BACKGROUND: The response to antiviral therapy of chronic hepatitis C virus (HCV) infection is determined by virological, environmental and genetic factors. OBJECTIVE: The hypothesis was tested that the expression of specific genes and their haplotype frequencies can differentiate between non-responders (NRs) and sustained virological responders (SVRs) to antiviral treatment. METHODS: A methodological approach based on molecular marker discovery and validation was used to study the genes influencing the antiviral treatment in lymphoblastoid cell lines from 74 genotype 1b HCV patients (44 from Southern Italy and 30 from Northern Italy) treated with pegylated interferon (IFN) alpha and ribavirin. Furthermore, an association study was performed, testing three single nucleotide polymorphisms (SNPs) of suppressor of cytokine signalling 3 (SOCS3) in 162 NR and 184 SVR subjects (SOCS3 -8464 A/C (rs12952093), -4874 A/G (rs4969170) and 1383 A/G, (rs4969168)). RESULTS: SOCS3 basal expression levels were significantly increased in two independent sets of NR groups (p<0.05). A highly significant association was found between NRs and both the positively associated haplotype (OR = 2.01, 95% CI 1.45 to 2.79, p = 0.0002) and the negatively associated haplotype (OR = 0.56, 95% CI 0.42 to 0.76, p = 0.0014). In particular, the SOCS3 -4874 AA genotype was strongly associated with failure of antiviral therapy (OR = 4.00, 95% CI 2.09 to 7.66, p = 0.0003) and the AA genotype carriers had significantly higher SOCS3 mRNA and protein levels (p<0.05). CONCLUSIONS: Basal levels of SOCS3, an inhibitor of the IFN alpha-induced Janus kinase-signal transducer and activator of transcription pathways, and its genetic polymorphisms influence the outcome of antiviral treatment. SOCS3 thus represents a novel blood biomarker for the a priori prediction of treatment response.

Hepatitis C virus carriers with persistently normal ALT levels: biological peculiarities and update of the natural history of liver disease at 10 years.

Some chronic hepatitis C (CHC) patients exhibit persistently normal alanine aminotransferase (ALT) levels (PNAL). Patients with PNAL experience significantly milder disease. In order to understand the differences between CHC patients with elevated ALT levels compared with those with PNAL better, we compared epidemiological, immunological and histological findings, in particular, the value of proliferating hepatocyte activity (PCNA) between the two groups of patients. We studied 40 chronic hepatitis C virus (HCV) carriers with increased ALT who underwent liver biopsy for histological diagnosis and determination of clinical prognosis, and 24 PNAL patients under follow-up for 10 years. Immunological response to different HCV genomic epitopes was tested in both the control group and in PNAL subjects. PCNA values from liver specimens of all patients as well as liver biopsies of PNAL patients at time points 0 and 5 years were calculated according to Hall et al.Age, sex and body mass index (BMI) were not significantly different between the two groups. The median liver histology stage was significantly higher in HCV carriers vs the PNAL group (2.5, range = 2-6 vs 1.5, range = 1-2; P < 0.01). Among PNAL patients, histological stage was not statistically different at the three time points considered. Interferon (IFN)-gamma production was comparable in the two groups. PCNA was significantly higher in the group with elevated ALT levels vs the PNAL group (8%, range = 4-15%vs 5% range = 3-8%; P < 0.05) and no statistically significant differences were found in PNAL patients at time points 0, 5 and 10 years. This study confirms that progression to cirrhosis is slow or absent in PNAL patients after 10 years of follow-up. Accordingly, the hepatic proliferative activity index is low and seems to be stable over time.

Increased vascular endothelial growth factor mRNA expression in the heart of streptozotocin-induced diabetic rats.

The aim of the present study was to evaluate vascular endothelial growth factor (VEGF), fms-like tyrosine kinase 1 (flt-1), and fetal liver kinase (flk-1) expression in the heart of experimental diabetic rats. Ten young adult male Wistar rats (5 streptozotocin [STZ]-induced diabetic rats, without insulin treatment, and 5 controls) were studied. Ninety days after the induction of diabetes, semiquantitative reverse transcription (RT)-polymerase chain reaction (PCR) coamplification of VEGF/glyceraldehyde 3-phosphate dehydrogenase (GAPDH) transcription was performed. RT-PCR was also performed for VEGF receptors flk-1 and flt-1. VEGF mRNA expression, at 234 bp, was detectable in the heart of the rats and was significantly higher in those with diabetes. Densitometric analysis of PCR products showed that VEGF mRNA levels were meanly 4.8-fold higher in STZ-induced diabetic rats than controls (VEGF/GAPDH densitometric ratio, 3.46 +/- 0.20 v 0.74 +/- 0.10, P <.001). No significant difference was found in flt-1 and flk-1 amplification products between STZ-induced diabetic rats and controls (flt-1/GAPDH densitometric ratio, 0.58 +/- 0.01 v 0.64 +/- 0.05, P>.1; flk-1/GAPDH densitometric ratio, 0.66 +/- 0.10 v 0.7 +/- 0.06, P >.2). The increase in VEGF mRNA expression observed in this experimental diabetic model is in contrast with the typical impairment in collateral vessels of diabetic hearts. This apparent discrepancy might be explained by a resistance of cardiac tissue to VEGF. The lack of mRNA flt-1 and flk-1 overexpression in diabetic hearts could be one of the mechanisms for this resistance.

Hepatic uptake of organic anions affects the plasma bilirubin level in subjects with Gilbert's syndrome mutations in UGT1A1.

Although in Gilbert's syndrome (GS), bilirubin glucuronidation is impaired due to an extra TA in the TATA box of the promoter of the gene for bilirubin UDP-glucuronosyltransferase 1 (UGT1A1), many GS homozygotes lack unconjugated hyperbilirubinemia. Accordingly, an additional defect in bilirubin transport might be required for phenotypic expression. Plasma bilirubin and the early fractional hepatic uptake rate (BSP K(1)) of a low dose of tetrabromosulfophthalein (0.59 micromol/kg) were determined in (1) 15 unrelated patients with unconjugated hyperbilirubinemia plus 12 random controls; (2) 4 unrelated GS probands and 15 of their first-degree relatives; (3) 7 unrelated patients with hemolysis due to beta-Thalassemia minor. Subjects were classified by DNA sequencing of the promoter region of both UGT1A1 alleles. In group 1, GS homozygotes showed a highly significant negative linear correlation between plasma bilirubin levels and BSP K(1). BSP K(1) values overlapped considerably between GS and normal subjects, whereas, in group 2, they were clustered within, and sharply segregated among, families. Patients with hemolysis, despite elevated plasma bilirubin levels, had mean BSP K(1) values similar to the normal subjects. Within each GS subgroup with defined UGT1A1 mutations, the plasma bilirubin level is in part determined by the organic anion uptake rate, assessed by early plasma disappearance of low-dose BSP. The lower BSP uptake in GS is not secondary to the hyperbilirubinemia, but probably caused by (an) independent, genetically determined defect(s) in hepatic transport mechanism(s), shared by BSP and bilirubin, that are likely necessary for phenotypic expression of GS.

Natural history of hepatitis C virus carriers with persistently normal aminotransferase levels.

BACKGROUND & AIMS: Some patients with serum hepatitis C virus (HCV) have persistently normal aminotransferase (ALT) levels and are affected by cirrhosis. This study prospectively evaluated progression of the disease in a group of anti-HCV-positive patients with persistently normal ALT levels. METHODS: Thirty-seven subjects were studied. Each subject underwent liver biopsy at baseline and after 5 years of follow-up. At baseline, serum samples were tested for genotypes and HCV RNA load. ALT levels and serum HCV RNA were tested every other month and every 6 months, respectively. Patients with increased ALT were discharged from the study and treated with IFN. Five years after the end of IFN therapy, a liver biopsy was performed. RESULTS: Liver biopsy at baseline showed chronic hepatitis in 34 patients and normal histology in 3 patients, 2 of whom were negative for HCV RNA and 1 positive. HCV genotypes were distributed as follows: 2a, 56%; 1b, 41%; and 1a, 3%. At the end of 7-year follow-up, 73% of the patients still had normal ALT values. Liver histology after 5 years was comparable to that observed at entry to study. CONCLUSIONS: Most patients with persistently normal ALT serum levels have very mild chronic hepatitis. However, healthy anti-HCV-positive subjects exist. In patients with HCV-related chronic hepatitis associated with persistently normal ALT levels, the grade of disease activity does not increase over years and progression to cirrhosis is slow or absent.

Activation of 'immediate-early' genes by estrogen is not sufficient to achieve stimulation of DNA synthesis in rat uterus.

17 beta-estradiol, a long acting estrogen that is mitogenic for rat uterus in vivo, or the short acting estrogens estriol and 16 alpha-estradiol, not mitogenic on their own, were injected into adult, castrated rats and their effect on uterine gene expression and rate of DNA synthesis were compared. All three compounds increased steady-state mRNA concentration of c-fos, c-jun and c-myc proto-oncogenes to comparable levels (2 hrs after treatment), whereas only 17 beta-estradiol was found to stimulate significantly DNA synthesis (20-22 hrs later). Based on the different retention time of the tested estrogens in rat tissues, it is concluded that a short exposure to the hormone is sufficient to render uterine cells competent to progress through the cell cycle, via activation of 'immediate-early' genes expression, but that stimulation of DNA synthesis requires further changes, achieved via a prolonged exposure of the cells to the estrogenic stimulus.

Estrogen stimulates transcription of c-jun protooncogene.

Estrogen is a mitogen for the rat uterus, where it induces transient activation of c-fos and c-myc protooncogene expression, followed by increases in DNA synthesis and cell proliferation. JUN-C, the product of the c-jun protooncogene, is a nuclear protein that can interact with FOS to modulate the activity of AP-1-responsive promoters. To test whether c-jun is a target for estrogen regulation, we measured the effects of 17 beta-estradiol on the expression of this gene in rat uterus. A human c-jun cDNA probe detects in rat uterus two mRNA species of 2.5 and 3.2 kilobases. Treatment of the animals with estrogen results in a rapid transient increase in the concentrations of these mRNAs; a 4- to 5-fold increase over the prestimulation level was detected starting 30 min after estrogen injection and lasting for 2 h, with a return to the prestimulation level after 4 h. In accordance with the results obtained by analysis of the mRNA, we found that estrogen increases 3- to 4-fold c-jun gene transcription in the uterus, at the same time it induces its mRNA accumulation. The ability of estrogen to induce c-jun gene expression was not abolished by the protein synthesis inhibitor cycloheximide, suggesting that transcriptional activation of this protooncogene is a primary response to the hormone. Furthermore, we found that in the estrogen-responsive MCF-7 human mammary carcinoma cells, estrogen stimulates transcription of a reporter gene containing four copies of a jun/AP-1 response element. These data demonstrate that c-jun gene expression is regulated by estrogen and suggest that JUN-C could play a role in the activation of cell proliferation by estrogen.