Clinical course of chronic hepatitis B (CHB) presented with normal ALT in Asian American patients.

The clinical course for chronic hepatitis B (CHB) patients with normal ALT and with or without minimal histologic activity remains unclear. We assessed frequency, amplitude, disease activities, and associated factors of ALT and/or AST flares in this subpopulation. Forty-seven consecutive treatment naïve Asian patients with CHB were enrolled from two liver clinics between December 2003 and January 2013, who had normal baseline ALT by routine clinical biochemical testing performed 6 weeks before or after the liver biopsy. We defined a flare as elevation of ALT/AST above the upper limit of normal of ALT/AST. The mean follow-up was 37.6 (CI = 12, 88) months, and the mean age at entry into the study was 43.3 (CI = 19, 65); 22/47 (46.8%) were males; 15/45 (33.3%), HBeAg+; 68.1% had stage 0-1 fibrosis; 63.8% had grade 0-1 inflammation. During follow-up, 13/47 (27.7%) cases developed ALT flare at least once in a mean of 13.5 (CI = 2, 43) months after liver biopsy; ALT flare was not associated with baseline ALT level, fibrosis stage, inflammation grade, hepatitis B virus (HBV) DNA load, HBeAg status, HBV genotype, HBV precore and basal core promoter mutations. 11/13 (84/6%) of ALT flares resolved during follow-up. 13/13 (100%) of ALT flares met AASLD treatment criteria, but only 6/13 (46.2%) were on HBV treatment. Serum ALT and/or AST flares occur frequently in CHB carriers who initially presented with normal ALT during pretreatment period. Thus, regular follow-up is warranted despite status of ALT/AST. No clinical factors were found to be associated with ALT flares.

Response to tenofovir monotherapy in chronic hepatitis B patients with prior suboptimal response to entecavir.

Both entecavir (ETV) and tenofovir (TDF) are potent antiviral agents for hepatitis B virus (HBV). Suboptimal response (SOR) following antiviral therapy is associated with an increased risk of subsequent treatment failure and viral resistance. It remains unclear whether switching to TDF is a reasonable approach in patients with SOR to ETV treatment. This study was aimed to determine how HBV patients with SOR to ETV respond to TDF monotherapy. Data of patients with SOR to ETV (failure to achieve >1 log(10) HBV-DNA reduction during the last 24 weeks of ETV treatment) who were switched to TDF monotherapy during 2005 and 2010 were reviewed. Treatment adherence was assessed by pill-count. Fourteen patients (2.9%) were identified from a total cohort of 482 ETV-treated patients. All 14 patients were Chinese and were infected with HBV genotype C (71%) or B (29%). Nine patients were men, and the median age was 41.5 years (19-64). Twelve were treatment naïve (one lamivudine- and one peginterferon-experienced patient); 85.7% were HBeAg positive. The median baseline HBV-DNA was 7.55 (5.30-9.40) log(10) copies/mL, and 57% had abnormal serum alanine aminotransferase (ALT) levels. Precore and/or basal core promoter mutations were detected in four patients, whereas no genotypic resistance was detected at baseline and before switching to TDF. The median duration of ETV treatment was 64.5 (26-126) weeks. The median HBV-DNA at the time of switching to TDF was 3.69 (3.00-4.90) log(10) copies/mL. The median HBV-DNA reduction from baseline and during the last 6-month observation period prior to switching to TDF was 4.04 (0.51-6.06) log(10) and 0.43 (-0.09-1.13) log(10) copies/mL, respectively. After the switching to TDF, all 14 patients (100%) achieved undetectable HBV-DNA and ALT normalization within a median duration of 30 weeks. In 12 patients who were HBeAg positive, HBeAg seroconversion was observed in two patients after TDF treatment of 75- and 84-weeks duration. There was no virological breakthrough observed after switching to TDF with a median follow-up period of 50 (24-160) weeks. TDF treatment was safe and well tolerated. In conclusion, suboptimal response to ETV is rare (approximately 3%). TDF monotherapy is safe and very effective in the management of HBV patients with SOR to ETV.

Hepatitis C treatment among racial and ethnic groups in the IDEAL trial.

Previous studies of chronic hepatitis C virus (HCV) treatment have demonstrated variations in response among racial and ethnic groups including poorer efficacy rates among African American and Hispanic patients. The individualized dosing efficacy vs flat dosing to assess optimaL pegylated interferon therapy (IDEAL) trial enrolled 3070 patients from 118 United States centres to compare treatment with peginterferon (PEG-IFN) alfa-2a and ribavirin (RBV) and two doses of PEG-IFN alfa-2b and RBV. This analysis examines treatment response among the major racial and ethnic groups in the trial. Overall, sustained virologic response (SVR) rates were 44% for white, 22% for African American, 38% for Hispanic and 59% for Asian American patients. For patients with undetectable HCV RNA at treatment week 4, the positive predictive value of SVR was 86% for white, 92% for African American, 83% for Hispanic and 89% for Asian American patients. The positive predictive values of SVR in those with undetectable HCV RNA at treatment week 12 ranged from 72% to 81%. Multivariate regression analysis using baseline characteristics demonstrated that treatment regimen was not a predictor of SVR. Despite wide-ranging SVR rates among the different racial and ethnic groups, white and Hispanic patients had similar SVR rates. In all groups, treatment response was largely determined by antiviral activity in the first 12 weeks of treatment. Therefore, decisions regarding HCV treatment should consider the predictive value of the early on-treatment response, not just baseline characteristics, such as race and ethnicity.

MicroRNA-150 alleviates acute myocardial infarction through regulating cardiac fibroblasts in ventricular remodeling.

OBJECTIVE: The aim of this study was to investigate the effect of microRNA-150 on the regulation of myocardial fibrosis and ventricular remodeling in rats with acute myocardial infarction (AMI). MATERIALS AND METHODS: The AMI rats model was established by the ligation of the left anterior descending coronary artery (LAD) in vivo. After AMI procedures, the rats were injected with microRNA-150 lentivirus overexpression or negative control, respectively. Cardiac function of rats was evaluated by echocardiography. Hematoxylin and eosin (HE) staining and Masson trichrome were performed to evaluate myocardial fibrosis in each rat. Meanwhile, cardiomyocyte apoptosis was detected by terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) method. The expression levels of microRNA-150, col1α1, col1α2, col3 and α smooth muscle actin (α-SMA) in the border zone of rat infarct myocardium were detected by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) and Western blot, respectively. RESULTS: MicroRNA-150 expression in the border zone of infarct myocardium decreased significantly at day 28 after AMI (p<0.05). Overexpressing microRNA-150 significantly improved cardiac function, decreased collagen volume fraction (CVF) and attenuated cardiomyocyte apoptosis in rats. Furthermore, the expression levels of col1ɑ1, col1ɑ2, col3 and α-SMA in the border zone of infarct myocardium were remarkably down-regulated in rats overexpressing microRNA-150 compared with those of controls (p<0.001). CONCLUSIONS: MicroRNA-150 expression in the border zone of rat infarct myocardium decreased at day 28 after AMI. In addition, the upregulation of microRNA-150 in myocardial tissue could inhibit myocardial fibrosis and improve ventricular remodeling at post-AMI.

An expert consensus for the management of chronic hepatitis B in Asian Americans.

BACKGROUND: Hepatitis B virus (HBV) infection is common with major clinical consequences. In Asian Americans, the HBsAg carrier rate ranges from 2% to 16% which approximates the rates from their countries of origin. Similarly, HBV is the most important cause of cirrhosis, hepatocellular carcinoma (HCC) and liver related deaths in HBsAg positive Asians worldwide. AIM: To generate recommendations for the management of Asian Americans infected with HBV. METHODS: These guidelines are based on relevant data derived from medical reports on HBV from Asian countries as well as from studies in the HBsAg positive Asian Americans. The guidelines herein differ from other recommendations in the treatment of both HBeAg positive and negative chronic hepatitis B (CHB), in the approach to HCC surveillance, and in the management of HBV in pregnant women. RESULTS: Asian American patients, HBeAg positive or negative, with HBV DNA levels >2000 IU/mL (>104 copies/mL) and ALT values above normal are candidates for anti-viral therapy. HBeAg negative patients with HBV DNA >2000 IU/mL and normal ALT levels but who have either serum albumin <3.5 g/dL or platelet count <130 000 mm3 , basal core promoter (BCP) mutations, or who have first-degree relatives with HCC should be offered treatment. Patients with cirrhosis and detectable HBV DNA must receive life-long anti-viral therapy. Indications for treatment include pregnant women with high viraemia, coinfected patients, and those requiring immunosuppressive therapy. In HBsAg positive patients with risk factors, life-long surveillance for HCC with alpha-fetoprotein (AFP) testing and abdominal ultrasound examination at 6-month intervals is required. In CHB patients receiving HCC treatments, repeat imaging with contrast CT scan or MRI at 3-month intervals is strongly recommended. These guidelines have been assigned to a Class (reflecting benefit vs. risk) and a Level (assessing strength or certainty) of evidence. CONCLUSIONS: Application of the recommendations made based on a review of the relevant literature and the opinion of a panel of Asian American physicians with expertise in HBV treatment will inform physicians and improve patient outcomes.

Direct detection of circulating hepatitis C virus RNA using probes from the 5' untranslated region.

Diagnostic testing for hepatitis C virus (HCV) infection currently is based on the presence of anti-HCV antibodies or a positive HCV RNA polymerase chain reaction (PCR) test. Although HCV RNA PCR is a sensitive and specific technique, widespread application is limited. Moreover, HCV RNA PCR is subject to false-positive reactions through contamination and is inherently difficult to standardize and quantitate. To overcome limitations of HCV RNA PCR, we produced both cDNA and riboprobes from a 241 nucleotide sequence of the 5' untranslated region of the HCV genome for slot hybridization. Hybridization was absent using normal human serum, horse serum, or hepatic cellular RNA from noninfected liver. Hybridization occurred predominantly with positive-stranded HCV RNA and was abolished by pretreatment with RNase A. Slot hybridization was performed on serum samples from 60 patients with chronic HCV infection and a positive HCV RNA PCR and 20 patients with liver diseases unrelated to HCV who had a negative HCV RNA PCR. Slot hybridization with cDNA and riboprobes showed concordance with HCV RNA PCR of 95 and 98.3%, respectively. There were no false-positive reactions in controls. The sensitivity of riboprobe hybridization was comparable to that of one stage HCV RNA PCR using 5' untranslated region primers. Riboprobe hybridization with the HCV H strain standard was positive in the dilution corresponding to 10(-6) chimpanzee infectious doses50/ml. The density of the hybridization signals correlated significantly with the mass of an RNA standard extracted from the liver of a patient with HCV infection. The relative quantities of HCV RNA in the sera of selected patients varied and were not correlated with the duration of disease or the histopathological stage. The highest relative quantities were associated with concurrent immunosuppression. We conclude that slot hybridization is a sensitive, specific alternative to HCV RNA PCR that can be directly quantitated using appropriate HCV RNA standards.

p190 RhoGAP, the major RasGAP-associated protein, binds GTP directly.

In mitogenically stimulated cells, a specific complex forms between the Ras GTPase-activating protein (RasGAP) and the cellular protein p190. We have previously reported that p190 contains a carboxy-terminal domain that functions as a GAP for the Rho family GTPases. Thus, the RasGAP-p190 complex may serve to couple Ras- and Rho-mediated signalling pathways. In addition to its RhoGAP domain, p190 contains an amino-terminal domain that contains sequence motifs found in all known GTPases. Here, we report that p190 binds GTP and GDP through this conserved domain and that the structural requirements for binding are similar to those seen with other GTPases. While the purified protein is unable to hydrolyze GTP, we detect an activity in cell lysates that can promote GTP hydrolysis by p190. A mutated form of p190 that fails to bind nucleotide retains its RasGAP binding and RhoGAP activities, indicating that GTP binding by p190 is not required for these functions. The sequence of p190 in the GTP-binding domain, which shares structural features with both the Ras-like small GTPases and the larger G proteins, suggests that this protein defines a novel class of guanine nucleotide-binding proteins.

Identification of a novel human Rho protein with unusual properties: GTPase deficiency and in vivo farnesylation.

We have identified a human Rho protein, RhoE, which has unusual structural and biochemical properties that suggest a novel mechanism of regulation. Within a region that is highly conserved among small GTPases, RhoE contains amino acid differences specifically at three positions that confer oncogenicity to Ras (12, 59, and 61). As predicted by these substitutions, which impair GTP hydrolysis in Ras, RhoE binds GTP but lacks intrinsic GTPase activity and is resistant to Rho-specific GTPase-activating proteins. Replacing all three positions in RhoE with conventional amino acids completely restores GTPase activity. In vivo, RhoE is found exclusively in the GTP-bound form, suggesting that unlike previously characterized small GTPases, RhoE may be normally maintained in an activated state. Thus, amino acid changes in Ras that are selected during tumorigenesis have evolved naturally in this Rho protein and have similar consequences for catalytic function. All previously described Rho family proteins are modified by geranylgeranylation, a lipid attachment required for proper membrane localization. In contrast, the carboxy-terminal sequence of RhoE predicts that, like Ras proteins, RhoE is normally farnesylated. Indeed, we have found that RhoE in farnesylated in vivo and that this modification is required for association with the plasma membrane and with an unidentified cellular structure that may play a role in adhesion. Thus, two unusual structural features of this novel Rho protein suggest a striking evolutionary divergence from the Rho family of GTPases.

Characterization of endothelin receptors and effects of endothelin on diacylglycerol and protein kinase C in retinal capillary pericytes.

Retinal capillary pericyte is a cell type selectively lost in early diabetic retinopathy. The physiological function of pericytes is not yet clearly identified, although it probably has contractile properties. We determined the specific binding of endothelin 1, a 21-amino acid peptide with potent vasoconstrictive action, and the stimulation of diacylglycerol/protein kinase C (DAG/PKC) pathway in cultured retinal capillary pericytes by endothelin. A single specific binding site for 125I-labeled endothelin was identified, with an apparent Kd of 1.3 nM and a maximal binding capacity of approximately 1-2 x 10(5) sites/cell. Endothelin (100 nM) increased total cellular DAG content by 15% at 5 min and 24% at 10 min. When pericytes were labeled isotopically with [3H]glycerol, endothelin stimulated [3H]DAG formation by 100% at 10 min and 88% at 30 min. After 10 min of endothelin treatment, PKC activities were increased by 60 and 100% in the membranous and cytosolic pools, respectively. We conclude that bovine retinal capillary pericytes possess numerous high-affinity specific binding sites for endothelin that mediate the action of endothelin by the stimulation of the DAG/PKC pathway in pericytes. These findings suggest that endothelin is a regulator of the contractile properties of pericytes, which may be adversely affected in diabetic retinopathy.

Management of ascites.

The evaluation of ascites includes a directed history, focused physical examination, and diagnostic paracentesis with ascitic fluid analysis. Dietary sodium restriction and oral diuretics are the mainstay of therapy for the majority of patients with cirrhotic ascites. Transjugular intrahepatic portocaval shunt has emerged as the treatment of choice for selected patients with refractory ascites, although serial large-volume paracenteses should be attempted first. Early diagnosis, broad-spectrum antibiotics, and albumin infusion contribute to the successful management of spontaneous bacterial peritonitis (SBP). Referral for liver transplant evaluation should be considered at the first sign of decompensation and should not be delayed until development of ominous clinical features, such as refractory ascites and SBP.

A study of the binding ability of pre-S1 and S2 proteins of hepatitis B virus to human serum albumin.

To assess the relationship between pre-S proteins of HBV and polymerized human serum albumin (PHSA), a labeled avidin biotin ELISA was used to detect pre-S1, S2 and PHSA receptor (PHSAR) activity. PHSAR activity was only present in the samples positive for pre-S1 and/or S2, but not in the samples positive only for HBsAg. Pre-S1, S2 and PHSAR could in some degree be blocked by preincubating serum with PHSA, and the blocking efficiency of PHSA with respect to pre-S2 and PHSAR was similar, suggesting that pre-S2 is the dominant site for binding PHSA in vitro. We also found that PHSAR activity was detectable in 2 cases positive only for pre-S1, but not pre-S2. Furthermore, PHSA could selectively block pre-S1 and PHSAR activity in 2 cases negative for pre-S2, revealing that pre-S1 also possesses binding ability to PHSA, at least in a small number of cases. Using sandwich ELISA, we demonstrated the existence of complexes of HBV envelope proteins and human serum albumin (HSA) in some HBV infected serum samples. The possible significance of these complexes is discussed.

[An immunohistochemical study on pre-S proteins of hepatitis B virus].

An indirect immunohistochemical technique was established to detect pre-S1 and pre-S2 proteins in liver with monoclonal antibodies, and altogether 80 samples of liver were studied. Under light microscope, pre-S1 and pre-S2 were known to be expressed in a similar way and might be divided into three patterns: diffusion type, inclusion type and membrane type. Membranous type expression of both pre-S1 and pre-S2 was associated with activity of the liver diseases and liver cell necrosis. Pre-S1 and Pre-S2 were also expressed in several samples of hepatocellular carcinoma.

Extended criteria donor and severe intraoperative glucose variability: association with reoperation for hemorrhage in liver transplantation.

Reoperations for hemorrhage following liver transplantation (OLT) are commonly associated with increased morbidity and mortality. We sought to determine the incidence and risk factors for reoperation for hemorrhage among adult liver transplantations. We retrospectively analyzed 668 patients transplanted between January 2004 and November 2007. Within 30 days following transplantation one hundred eleven patients (16.6%) underwent 156 reoperations for hemorrhage, averaging 1.4 reoperations per patient. More than half of the reoperations occurred during the first 2 postoperative days. One-third of patients required 2 or more reoperations. Multivariate logistic regression analysis showed 4 independent risk factors: grafts from donors with multiple extended criteria, severe intraoperative glucose variability, intraoperative use of vasopressors, and red blood cell transfusion requirement. In conclusion, we identified several independent risk factors for reoperation due to hemorrhage following OLT. Avoidance of severe intraoperative glucose variability and careful evaluation of the benefits and risks of utilizing extended criteria donors must be considered before transplantation.

Black patients with chronic hepatitis C have a lower sustained viral response rate than non-Blacks with genotype 1, but the same with genotypes 2/3, and this is not explained by more frequent dose reductions of interferon and ribavirin*.

In previous hepatitis C virus (HCV) treatment studies, Black patients not only had a lower sustained viral response (SVR) rate to interferon and ribavirin (RBV) than non-Black patients but also a higher frequency of HCV genotype 1 (GT-1) infection. The aim of this community-based study was to determine whether Black patients have a lower SVR rate independent of genotype. We prospectively enrolled 785 patients (24.8% Black, 71.5% White, 3.7% others) who received interferon alpha-2b 3 MU three times weekly + RBV 1000-1200 mg/day for 24 weeks (GT-2/3) or 48 weeks (GT-1). Black patients were more commonly infected with GT-1 (86.8%vs 64.8%, P < 0.001) and less frequently had an SVR compared with non-Black patients (8.4%vs 21.6%, P < 0.001). Within GT-1, Black patients had a lower SVR rate than non-Black patients (6.1%vs 14.1%, P = 0.004) but not within GT-2/3 (50.0%vs 36.5%, P = 0.47). Black patients had lower baseline haemoglobin levels (14.8 vs 15.3 g/dL, P < 0.001) and neutrophil counts (2900 vs 4100/mm(3), P < 0.001) and required more frequent dose reductions of RBV (29.8%vs 18.5%, P < 0.001) and interferon (4.7%vs 1.6%, P = 0.012). However, dose reductions were not associated with lower SVR rates while early treatment discontinuations were (2.9%vs 25.7%, P < 0.001). Independent predictors of SVR were GT-1 [odds ratio (OR) 0.33; 95% confidence interval (CI) 0.20-0.55; P < 0.001], Black race (OR 0.45; 95% CI 0.22-0.93; P = 0.030), and advanced fibrosis, stages 3 + 4 (OR 0.53; 95% CI 0.31-0.92; P = 0.023). In conclusion, Black patients infected with HCV GT-1 (but not GT-2/3) have a lower SVR rate than non-Black patients. This is not explained by their lower baseline haemoglobin levels and neutrophil counts that lead to higher rates of ribavirin and interferon dose reductions.