[How to tackle the epidemic of diabetes: strategy at cantonal level]. / Faire face à l'épidémie de diabète: réponses à l'échelle d'un canton.

Switzerland is affected by a "diabetes epidemic". It is estimated that one in fifteen adult is affected by this disease. The human costs are consistent with more than 2/3 of the costs of diabetes related to complications. To reduce the impact of the disease on the population of the canton of Vaud, the "Cantonal Diabetes Program" is a program to slow the increasing incidence of the disease (primary prevention) and to improve the care to patients. The secondary prevention strategy is divided into three areas: daily life support to the diabetic patients, improvement of the interdisciplinary work and consolidation of proximity care structures. The innovative approach of this program, which aims to enhance partnerships by strengthening the autonomy of patients and caregivers interdisciplinary work, could be applied to other chronic diseases.

Intracellular accumulation of middle hepatitis B surface protein activates gene transcription.

While the natural intact protein does not possess any transactivator function, C-terminal truncation of the middle hepatitis B surface (MHBs) protein yields a novel transactivator function. We have previously found that the truncated transactivator protein, MHBs(t167), is not secreted but retained within the secretory pathway. Here, we provide evidence that when full-length MHBs is coexpressed with the truncated MHBs(t167) protein, the secretion of the full-length protein is inhibited and both proteins accumulate within the cell. We further show that MHBs, forcibly retained in the cell by C-terminal fusion to the endoplasmic reticulum retention signal KDEL (MHBsKDEL), mimics the effects of MHBs(t167) in enhancing the nuclear-binding activity of transcription factors NFkappaB and AP-1, and activation of NFkappaB- and AP-1-dependent transcription of reporter genes. As is the case for MHBs(t167), MHBsKDEL-dependent activation of NFkappaB is inhibited by the antioxidant N-acetyl-L-cysteine indicating the involvement of reactive oxygen intermediates and suggesting a similar mechanism of activation. This study suggests that the intracellular retention and accumulation of the normally secreted MHBs leads to oxidative stress and activation of transcription. This may be an important but not exclusive mechanism in hepatocarcinogenesis.

Improved detection of hepatitis B virus surface antigen by a new rapid automated assay.

The performance of hepatitis B virus (HBV) surface antigen (HBsAg) screening assays is continuously improved in order to reduce the residual risk of transfusion-associated hepatitis B. In a multicenter study, a new automated rapid screening assay, Elecsys HBsAg (Roche Diagnostics), was compared to well-established tests (Auszyme Monoclonal [overnight incubation] version B and IMx HBsAg [Abbott]). Included in the evaluation were 23 seroconversion panels; sera from the acute and chronic phases of infection; dilution series of various HBsAg standards, HBV subtypes, and S gene mutants; and isolated anti-HBV core antigen-positive samples. To challenge the specificity of the new assay, sera from HBsAg-negative blood donors, pregnant women, and dialysis and hospitalized patients and potentially cross-reactive samples were investigated. Elecsys HBsAg showed a higher sensitivity for HBsAg subtypes ad, ay, adw2, adw4, ayw1, ayw2, ayw4, and adr detection in dilution series of different standards or sera than Auszyme Monoclonal version B and/or IMx HBsAg. Acute hepatitis B was detected in 11 to 16 of 23 seroconversion panels between 2 and 16 days earlier with Elecsys HBsAg than with the alternative assays. Elecsys HBsAg and Auszyme Monoclonal version B detected HBsAg surface mutants with equal sensitivity. The sensitivity and specificity of Elecsys HBsAg were 100%. Auszyme Monoclonal version B had a 99.9% specificity, and its sensitivity was 96.6%. IMx HBsAg showed a poorer sensitivity and specificity than the other assays. In conclusion, Elecsys HBsAg permits earlier detection of acute hepatitis B and different HBV subtypes than the alternative assays. By using highly sensitive HBsAg screening assays, low-level HBsAg carriers among isolated anti-HBV core antigen-positive individuals can be detected.

Significance of antibodies to the recombinant E2 protein of hepatitis G virus in haemodialysis patients.

Patients on maintenance haemodialysis represent a high-risk group for parenterally transmitted viral infections, such as hepatitis B, C and G. In addition to hepatitis G virus (HGV) (GBV-C) RNA, analysed in previous studies, we characterized the seroprevalence rates of antibodies to the putative E2 protein (anti-E2) of HGV in a German cohort of patients on maintenance dialysis (n = 72) in comparison to healthy blood donors (n = 100). The presence of anti-E2 and/or HGV RNA as indicators of present or past HGV infection could be demonstrated in 34.7% of patients and in 16% of the blood donors (P < 0.01). The infection rates with HGV seem to increase only during the first 6 years of haemodialysis. The simultaneous presence of viraemia and anti-E2 was found very rarely in patients and controls. Therefore, the emergence of anti-E2 indicates clearance of HGV viraemia. In conclusion, patients on haemodialysis are at high risk of acquiring HGV infection, but a chronic carrier state with viraemia is rare. The risk of infection is not strictly correlated with the duration of dialysis.

Prevalence of hepatitis C and G virus infection in chronic hemodialysis patients.

An RNA virus designated hepatitis G virus (HGV) has been recently identified in patients with acute and chronic liver disease. HGV is transfusion transmissible, it has global distribution, and it is present in the volunteer blood donor population in the United States. One hundred sixty patients undergoing maintenance hemodialysis at the University of Miami-affiliated unit were evaluated. There were 99 men and 61 women ranging in age from 22 to 80 years. Sixty percent had a history of blood transfusion, 6% had a history of drug abuse, and 9% were infected with the human immunodeficiency virus. HGV-RNA was detected by reverse-transcriptase polymerase chain reaction with amplification of two independent regions (5'-nontranslated region and NS5a coding region). Detection of digoxigenin-labeled amplification products with specific capture probes to the coding and noncoding regions was performed with the Enzymun-test DNA on an ES-300 Immunoassay System (Boehringer-Mannheim, Mannheim, Germany). Hepatitis C antibodies were measured with anti-hepatitis C virus enzyme-linked immunosorbent third-generation assays and hepatitis C virus RNA by reverse-transcriptase polymerase chain reaction. There were 32 (20%) patients with detectable HGV RNA with both primer pairs. Because of possible mutations, the HGV virus may be detectable only with one primer pair. We considered the latter as indeterminate: 12 had detectable levels to the NS5a region only, seven to the 5'-nontranslated region, and six had borderline results. Detectable and indeterminate samples were confirmed by repeat measurements in a new blood sample. Seven of 24 (29%) patients with detectable hepatitis C virus RNA had coexisting HGV with one or both HGV primer pairs (four with both and three with one). Five patients were hepatitis B surface antigen positive and HGV negative. We conclude that HGV infection is prevalent in our dialysis patients. The clinical significance of HGV infection remains to be established.

The hepatitis B virus MHBst167 protein is a pleiotropic transactivator mediating its effect via ubiquitous cellular transcription factors.

C-terminally truncated surface proteins of hepatitis B virus (HBV) are frequently translated from genomically integrated viral sequences. They may be relevant for hepatocarcinogenesis by stimulating gene expression. First, we examined the transactivating potential of middle hepatitis B surface protein truncated at amino acid (aa) position 167 (MHBst167) on the HBV regulatory element. In transient cotransfection assays using Chang liver or HepG2 cell lines and chloramphenicol acetyltransferase (CAT) reporter constructs only the HBV enhancer I, but no other HBV regulatory elements like the X promoter, the S1 or S2 promoter or the enhancer II/core promoter could be stimulated by MHBst167. Since there is no evidence for a direct interaction of MHBst167 with DNA, we subsequently analysed whether cellular transcription factors were involved in mediating transactivation. This was tested both with isolated transcription-factor-binding sites and in the natural context of viral and cellular promoter elements. Deletion analysis and electrophoretic mobility shift assays revealed that Sp1, AP1 and NF-kappa B can mediate transactivation by MHBst167. No involvement of CREB, NF1 or the liver-specific factor C/EBP was found. These data indicate that MHBst167 is a pleiotropic, non-liver-specific transactivator which exerts its effect via ubiquitous cellular transcription factors that are also involved in the regulation of expression of cellular genes relevant for proliferation and inflammation.

Detection of the hepatitis G virus genome among injecting drug users, homosexual and bisexual men, and blood donors.

The recently identified hepatitis G virus (HGV) is parenterally transmitted; the impact of sexual transmission is unknown. Moreover, it is unclear what proportion of HGV-infected persons may develop persistent viremia. Sera from injecting drug users (IDUs), non-drug-injecting homosexual and bisexual men with high levels of sexual risk behavior, and blood donors were tested for HGV RNA and hepatitis C virus (HCV) RNA by reverse transcriptase-polymerase chain reaction and for antibodies to human immunodeficiency virus, hepatitis B virus, and HCV. HGV RNA was detected in 33% of IDUs (n = 130), 11% of homosexual and bisexual men (n = 101), and 2% of blood donors (n = 90). HGV RNA seroprevalence significantly decreased with increasing time since first drug injection, whereas the seroprevalences of both HCV RNA and anti-HCV antibody increased. Thus, a high proportion of HGV-infected persons may clear the virus and develop protective antibodies. The relatively high HGV RNA prevalence among non-drug-injecting homosexual and bisexual men indicates that sexual contact may be another important route of HGV transmission.

Integrated hepatitis B virus X and 3' truncated preS/S sequences derived from human hepatomas encode functionally active transactivators.

The hepatitis B virus (HBV) frequently integrates into hepatocellular genomic DNA during viral infection. Transcriptional transactivators encoded by integrated HBV X and 3' truncated preS/S sequences are known to stimulate gene expression from homologous and heterologous promoters. Here we demonstrate that 21 of 26 (81%) hepatocellular carcinoma tissues/cell lines contain coding sequences for at least one of the two known transactivators. Four integrated X and three preS/S transactivator sequences contained in five isolates from three hepatoma primary tissues or cell lines were used as examples to prove functionality of the encoded transactivators. In one case, where both X and preS/S sequences were present, dissection of X and preS/S transactivator sequences showed independent functionality. The investigation of X- and preS/S-specific RNA and protein expression revealed the existence of carboxyterminally truncated viral-cellular fusion proteins that were able to stimulate gene expression from the c-fos proto-oncogene promoter five- to ten-fold. These results demonstrate that structurally intact HBV transactivator sequences are integrated in the majority of HBV-associated HCCs/hepatoma cell lines. In all tested examples integrated DNAs had retained functionality as transactivators. This data thereby support indirectly the hypothesis of a possible involvement of HBV transactivators in liver cell proliferation and hepatocarcinogenesis.

Hepatitis B virus transactivator MHBst: activation of NF-kappa B, selective inhibition by antioxidants and integral membrane localization.

C-terminal truncation of the middle surface antigen from hepatitis B virus (MHBs) gives rise to a novel transactivating protein, called MHBst. In this study we show that MHBst like the HBx protein of HBV, can cause nuclear appearance of NF-kappa B DNA binding activity and induce various kappa B-controlled reporter genes. While an inhibitor of protein kinase C could not block gene induction by MHBst, the antioxidants N-acetyl-L-cysteine (NAC) and pyrrolidine dithiocarbamate (PDTC) could potently suppress transactivation at mM and microM concentrations, respectively. Also, kappa B-dependent gene induction by the transactivator HBx was blocked. The effects were selective because PDTC did not interfere with MHBst and HBx-induced activation of the c-fos promoter/enhancer, nor with the basal activity of several other reporter genes lacking functional NF-kappa B binding motifs. Our data suggest that induction of a prooxidant state is crucial for the activation of NF-kappa B by MHBst and HBx and might be related to the hepatocarcinogenic potential of the viral proteins. MHBst had a subcellular localization unusual for a viral transactivator: it appeared to be an integral membrane protein of the endoplasmic reticulum.

A new procedure for assessment of proprioception.

A new method for the assessment of proprioception was developed and tested with 40 healthy subjects on two facial muscles (i.e., masseter and zygomatic muscles). The experiment was repeated after 3 1/2 months. In our study, proprioception was studied with respect to sensations arising from the muscle spindles and tendon organs. Therefore, myesthesia was investigated, which was assessed by the correspondence between a voluntary muscle contraction and its immediate replication. Good perception was defined by a small integral of differences, standardized by duration and intensity of the contraction, and its replication. Results show that this measure is independent of the characteristics of muscle activation. In concordance with our hypothesis, myesthesia was superior in a muscle richly supplied with muscle spindles and afferent fibers (i.e., masseter muscle), to that for a muscle less prepared for afferent information processing (i.e., zygomatus major).