Week 4 viral load predicts long-term suppression of hepatitis B virus DNA during antiviral therapy: improving hepatitis B treatment in the real world.

BACKGROUND: Entecavir and tenofovir potently suppress hepatitis B virus (HBV) replication so that serum HBV DNA levels <20 IU/mL can be achieved after 2 years. Despite this, inadequate suppression is reported in >20% of cases for unclear reasons. AIM: We tested whether 4-week viral load (VL) assessment could improve 96-week treatment outcome. METHODS: Data on all chronic hepatitis B patients treated with entecavir or tenofovir between 2005 and 2014 were entered prospectively. Full data capture included pre-treatment, weeks 4, 24, 48 and 96 HBV DNA titre, HBeAg, age, gender, antiviral agent and dose escalation. Compliance data were compiled from pharmacy records, doctors' letters and clinic bookings/attendance. Time to achieve complete viral suppression (HBV DNA < 20 IU/mL) was graphed using Kaplan-Meier curves. Factors affecting this were examined using a multivariate Cox Proportional Hazard model. RESULTS: Among 156 patients treated, 72 received entecavir and 84 tenofovir. Pre-treatment HBV DNA titre, 4-week assessment and compliance impacted significantly on time to complete viral suppression. At 96 weeks, 90% of those assessed as compliant by 4-week HBV DNA had complete viral suppression versus 50% followed by 6-month VL estimation. Continuing care by the same physician was related to 4-week VL testing and optimal compliance. CONCLUSIONS: Medium-term outcomes of HBV antiviral therapy are improved by early on-treatment VL testing, facilitating patient engagement and improved compliance. The observation that 90% complete viral suppression after 2 years monotherapy is achievable in a routine clinic setting questions the need for combination therapy in HBV cases with suboptimal response.

PPARgamma inhibits hepatocellular carcinoma metastases in vitro and in mice.

BACKGROUND: We have previously demonstrated that peroxisome proliferator-activated receptor (PPARγ) activation inhibits hepatocarcinogenesis. We aim to investigate the effect of PPARγ on hepatocellular carcinoma (HCC) metastatic potential and explore its underlying mechanisms. METHODS: Human HCC cells (MHCC97L, BEL-7404) were infected with adenovirus-expressing PPARγ (Ad-PPARγ) or Ad-lacZ and treated with or without PPARγ agonist (rosiglitazone). The effects of PPARγ on cell migration and invasive activity were determined by wound healing assay and Matrigel invasive model in vitro, and in an orthotopic liver tumour metastatic model in mice. RESULTS: Pronounced expression of PPARγ was demonstrated in HCC cells (MHCC97L, BEL-7404) treated with Ad-PPARγ, rosiglitazone or Ad-PPARγ plus rosiglitazone, compared with control (Ad-LacZ). Such induction markedly suppressed HCC cell migration. Moreover, the invasiveness of MHCC97L and BEL-7404 cells infected with Ad-PPARγ, or treated with rosiglitazone was significantly diminished up to 60%. Combination of Ad-PPARγ and rosiglitazone showed an additive effect. Activation of PPARγ by rosiglitazone significantly reduced the incidence and severity of lung metastasis in an orthotopic HCC mouse model. Key mechanisms underlying the effect of PPARγ in HCC include upregulation of cell adhesion genes, E-cadherin and SYK (spleen tyrosine kinase), extracellular matrix regulator tissue inhibitors of metalloproteinase (TIMP) 3, tumour suppressor gene retinoblastoma 1, and downregulation of pro-metastatic genes MMP9 (matrix metallopeptidase 9), MMP13, HPSE (heparanase), and Hepatocyte growth factor (HGF). Direct transcriptional regulation of TIMP3, MMP9, MMP13, and HPSE by PPARγ was shown by ChIP-PCR. CONCLUSION: Peroxisome proliferator-activated receptor-gamma exerts an inhibitory effect on the invasive and metastatic potential of HCC in vitro and in vivo, and is thus, a target for the prevention and treatment of HCC metastases.

Hepatic microcirculation in fatty liver disease.

Nonalcoholic fatty liver disease (NAFLD), the most common cause of steatosis, is associated with visceral obesity and insulin resistance. With more severe risk factors (obesity, type 2 diabetes [T2D], metabolic syndrome), steatosis may be complicated by hepatocellular injury and liver inflammation (steatohepatitis or NASH). NASH can lead to perisinusoidal fibrosis and cirrhosis. Fat-laden hepatocytes are swollen, and in steatohepatitis, further swelling occurs due to hydropic change (ballooning) of hepatocytes to cause sinusoidal distortion, as visualized by in vivo microscopy, reducing intrasinusoidal volume and microvascular blood flow. Involvement of other cell types (sinusoidal endothelial cells, Kupffer cells, stellate cells) and recruitment of inflammatory cells and platelets lead to dysregulation of microvascular blood flow. In animal models, the net effect of such changes is a marked reduction of sinusoidal space (approximately 50% of control), and a decrease in the number of normally perfused sinusoids. Such microvascular damage could accentuate further liver injury and disease progression in NASH. The fatty liver is also exquisitely sensitive to ischemia-reperfusion injury, at least partly due to the propensity of unsaturated fatty acids to undergo lipid peroxidation in the face of reactive oxygen species (ROS). This has important clinical consequences, particularly limiting the use of fatty donor livers for transplantation. In this review, we discuss available data about the effects of steatosis and steatohepatitis on the hepatic microvascular structure and sinusoidal blood flow, highlighting areas for future investigation.

Isolation of multipotent progenitor cells from human fetal liver capable of differentiating into liver and mesenchymal lineages.

Little is known about the differentiation capabilities of nonhematopoietic cells of the human fetal liver. We report the isolation and characterization of a human fetal liver multipotent progenitor cell (hFLMPC) population capable of differentiating into liver and mesenchymal cell lineages. Human fetal livers (74-108 days of gestation) were dissociated and maintained in culture. We treated the colonies with geneticin and mechanically isolated hFLMPCs, which were kept in an undifferentiated state by culturing on feeder layers. We derived daughter colonies by serial dilution, verifying monoclonality using the Humara assay. hFLMPCs, which have been maintained in culture for up to 100 population doublings, have a high self-renewal capability with a doubling time of 46 h. The immunophenotype is: CD34+, CD90+, c-kit+, EPCAM+, c-met+, SSEA-4+, CK18+, CK19+, albumin-, alpha-fetoprotein-, CD44h+, and vimentin+. Passage 1 (P1) and P10 cells have identical morphology, immunophenotype, telomere length, and differentiation capacity. Placed in appropriate media, hFLMPCs differentiate into hepatocytes and bile duct cells, as well as into fat, bone, cartilage, and endothelial cells. Our results suggest that hFLMPCs are mesenchymal-epithelial transitional cells, probably derived from mesendoderm. hFLMPCs survive and differentiate into functional hepatocytes in vivo when transplanted into animal models of liver disease. hFLMPCs are a valuable tool for the study of human liver development, liver injury, and hepatic repopulation.

Management of chronic hepatitis B virus infection: a new era of disease control.

When assessing patients with chronic hepatitis B virus (HBV) infection, consider the state of viral replication, the immune response and whether viral mutations could be present, as well as evidence for liver disease or extrahepatic manifestations. In wild-type infections, loss of hepatitis B e antigen (HBeAg), gain of anti-HBe and disappearance of HBV DNA from serum indicate immunosuppression of viral replication, or 'nonreplicative chronic HBV infection'. This 'healthy carrier' state must be distinguished from HBeAg-negative chronic hepatitis B (CHB) resulting from precore and core promoter mutations. HBeAg-negative CHB is common with genotypes D (Mediterranean region, south Asia) and C (north Asia) infections. Age, disease activity (alanine aminotransferase level) and severity (fibrosis stage, cirrhosis) influence treatment decisions. Following the marginal effectiveness of interferon and often temporary effectiveness of lamivudine due to drug resistance, treatment of CHB is entering a new era. Adefovir, entecavir, tenofovir, telbivudine and clevudine have equal or superior antiviral efficacy to lamivudine, whereas several agents are effective against lamivudine-resistant HBV. Pegylated-interferon (peginterferon) is superior to conventional interferon for obtaining sustained immunosuppression of HBV without drug resistance. Antiviral suppression of HBV replication for 2-5 years reverses hepatic fibrosis, prevents cirrhosis and, when cirrhosis is established, improves liver function, prevents hepatic decompensation and lowers the risk of liver cancer. Before embarking on immunosuppressive chemotherapy or organ transplantation in patients with chronic HBV infection, it is important to start antiviral therapy to prevent hepatitis flares. Antiviral therapy can be effective against membranous glomerulonephritis and polyarteritis nodosa caused by HBV. Further improvements in treatment of CHB are needed to prevent drug resistance and permanently suppress viral replication by eradicating viral templates or stimulating host immune responsiveness to HBV.

Management of chronic hepatitis C virus infection: a new era of disease control.

The management of chronic viral hepatitis has changed significantly with the availability of effective antiviral agents. There is now a high probability that timely intervention can arrest development of cirrhosis, thereby preventing mortality from portal hypertension, liver failure and liver cancer. This two-part review discusses the implications of this new era of antiviral therapy for physicians. The present review is about chronic hepatitis C virus (HCV); a similar review that considers the treatment of hepatitis B virus will be published in a later issue of the Internal Medicine Journal. Chronic HCV infection is common, but fibrotic progression of liver disease is slow and variable; many infected persons never develop cirrhosis. Case selection for antiviral therapy is crucial. The most effective therapy is a pegylated (long-acting) interferon with ribavirin. Sustained viral response (SVR) (absent viraemia 6 months after completing treatment) can be obtained in 40-60% of individuals infected with genotype 1 and in approximately 67% with genotype 4 after 12 months of treatment. Response rates are higher (75-85%) with genotypes 2 and 3 after only 6 months of treatment. Late relapse is negligible after SVR. This viral cure reverses hepatic fibrosis, reduces the risk of liver failure and of hepato-cellular carcinoma. Combination therapy requires a supportive setting to minimize the impact of side-effects and maximize therapeutic effectiveness. Overall management of HCV-infected persons must also embrace measures to improve quality of life by preventing or dealing with psychosocial issues and advocating lifestyle changes to counter comorbidity from alcohol, central obesity and insulin resistance. These latter factors favour fibrotic disease progression, complications of cirrhosis (such as hepatocellular carcinoma) and development of type 2 diabetes mellitus, as well as eroding the chances of SVR with antiviral therapy.

Ethical review of health research: a perspective from developing country researchers.

BACKGROUND: Increasing collaboration between industrialised and developing countries in human research studies has led to concerns regarding the potential exploitation of resource deprived countries. This study, commissioned by the former National Bioethics Advisory Commission of the United States, surveyed developing country researchers about their concerns and opinions regarding ethical review processes and the performance of developing country and US international review boards (IRBs). METHODS: Contact lists from four international organisations were used to identify and survey 670 health researchers in developing countries. A questionnaire with 169 questions explored issues of IRB review, informed consent, and recommendations. RESULTS: The majority of the developing country researchers were middle aged males who were physicians and were employed by educational institutions, carrying out research on part time basis. Forty four percent of the respondents reported that their studies were not reviewed by a developing country IRB or Ministry of Health and one third of these studies were funded by the US. During the review process issues such as the need for local language consent forms and letters for approval, and confidentiality protection of participants were raised by US IRBs in significantly higher proportions than by host country IRBs. CONCLUSION: This survey indicates the need for the ethical review of collaborative research in both US and host countries. It also reflects a desire for focused capacity development in supporting ethical review of research.

Bacteraemia following percutaneous dilational tracheostomy.

This study reports the incidence of bacteraemia following 106 consecutive bedside percutaneous tracheostomies. Post-tracheostomy blood culture results were compared with other blood cultures from the same population. The incidence of positive post-tracheostomy blood cultures was 10.4% (11/106), compared with 6.6% (7/106) for other blood cultures (odds ratio 1.64, 95% confidence interval 0.61-4.40, P = 0.46). Staphylococcus epidermidis was the most common organism cultured, 7/106 (6.6%) of post-tracheostomy cultures, compared with 3/106 (2.8%) for other cultures (odds ratio 2.43, 95% confidence interval 0.61-9.65, P = 0.33). The other four post-tracheostomy cultures grew an organism cultured from that patient's tracheal secretions. Seventy-four patients were receiving antibiotics at the time of tracheostomy, of these 7 (9.5%)-had positive blood cultures, a similar incidence (4 of 32, 12.5%) to those not receiving antibiotics (odds ratio 0.73, 95% confidence interval 0.20-2.70, P = 0.90). We conclude bacteraemia is a common complication of percutaneous tracheostomy; the causative organisms come from the patients' trachea or skin.

Multiple statistics for multiple events, with application to repeated infections in the growth factor studies.

Clinical studies that involve the recording of two or more distinct and well-defined events on each subject give rise to multiple event data. Treatment comparisons are usually reported in univariate analyses of time to first event or number of events observed. However, this approach may not uncover the 'full story' of the treatment effect; moreover, it may be inefficient because it does not make full use of the available data. There are a number of published statistical methods for analysing multiple event data. Using data from a real life example, this paper compares the results obtained using the 'older ad hoc' methods with those based on the more recent methods that utilize the multiplicity of the data.

Repairing the degenerative anterior mitral leaflet.

This is a consecutive, nonselected series of 18 patients with degenerative mitral regurgitation requiring a reparative operation on the anterior mitral leaflet. A new technique of double-breasting the two leaflets when flail septal segments are encountered is introduced.