Evaluation of pharmacokinetics and safety with bioequivalence of Amlodipine in healthy Chinese volunteers: Bioequivalence Study Findings.

BACKGROUND AND OBJECTIVE: Amlodipine, a main series of L-type calcium channel blockers (CCBs), exerts potent antihypertensive effects. The aim of this trial was to explore the pharmacokinetics (PK) and safety with bioequivalence of orally administered Amlodipine provided by two sponsors in healthy volunteers (HVs). METHODS: Two separate randomized, open-label, single-dose, crossover-design studies were conducted: a fasting study (n = 24) and a fed study (n = 24). In each study, HVs were randomized to Fangming Pharmaceutical Group (Test, T) followed by NORVASC® (Reference, R), or vice versa. Each study subject received a 5-mg Amlodipine tablet with a 15-day washout. The plasma concentrations of Amlodipine were measured using a LC-MS/MS method, and PK parameters were determined by noncompartmental model. RESULTS: Forty-eight healthy volunteers were enrolled. And overall demographics were as follows: the fasting study: female (n = 16/24), age (18-54 years), weight (47-76 kg), and BMI (19.5-26.0). The fed study: female (n = 16/24), age (20-49 years), weight (45.5-69 kg), and BMI (19.1-25.0). All PK endpoints met the pre-specific criteria for PK equivalence. In fasting subjects, the maximum plasma concentration (Cmax ) was 3.881 ± 0.982 ng/mL at 6 hours (median) of sponsor T, and 4.042 ± 1.147 ng/mL at 6 hours (median) of sponsor R. In fed subjects, Cmax was 3.312 ± 0.789 ng/mL at 6 hours (median) of sponsor T, and 3.392 ± 0.902 ng/mL at 5 hours (median) of sponsor R. Both fasting and fed studies achieved a plausible bioequivalence. CONCLUSIONS: Amlodipine is well tolerated and have a favorable safety profile. The observed adverse events were mild (the severity was assessed according to the Common Terminology Criteria for Adverse Events [version CTCAE4.03]) and all of them were recovered without severe sequences. And the bioequivalence is achieved under fasting and fed conditions, supporting the demonstration of biosimilarity.

High-throughput proteomic analysis of FFPE tissue samples facilitates tumor stratification.

Formalin-fixed, paraffin-embedded (FFPE), biobanked tissue samples offer an invaluable resource for clinical and biomarker research. Here, we developed a pressure cycling technology (PCT)-SWATH mass spectrometry workflow to analyze FFPE tissue proteomes and applied it to the stratification of prostate cancer (PCa) and diffuse large B-cell lymphoma (DLBCL) samples. We show that the proteome patterns of FFPE PCa tissue samples and their analogous fresh-frozen (FF) counterparts have a high degree of similarity and we confirmed multiple proteins consistently regulated in PCa tissues in an independent sample cohort. We further demonstrate temporal stability of proteome patterns from FFPE samples that were stored between 1 and 15 years in a biobank and show a high degree of the proteome pattern similarity between two types of histological regions in small FFPE samples, that is, punched tissue biopsies and thin tissue sections of micrometer thickness, despite the existence of a certain degree of biological variations. Applying the method to two independent DLBCL cohorts, we identified myeloperoxidase, a peroxidase enzyme, as a novel prognostic marker. In summary, this study presents a robust proteomic method to analyze bulk and biopsy FFPE tissues and reports the first systematic comparison of proteome maps generated from FFPE and FF samples. Our data demonstrate the practicality and superiority of FFPE over FF samples for proteome in biomarker discovery. Promising biomarker candidates for PCa and DLBCL have been discovered.

Catalytic Asymmetric (4+3) Cyclizations of In Situ Generated ortho-Quinone Methides with 2-Indolylmethanols.

The first catalytic asymmetric (4+3) cyclization of in situ generated ortho-quinone methides with 2-indolylmethanols has been established, which constructed seven-membered heterocycles in high yields (up to 95 %) and excellent enantioselectivity (up to 98 %). This approach not only represents the first catalytic asymmetric (4+3) cyclization of o-hydroxybenzyl alcohols, but also enabled an unprecedented catalytic asymmetric (4+3) cyclization of 2-indolylmethanols. In addition, a scarcely reported catalytic asymmetric (4+3) cyclization of para-quinone methide derivatives was accomplished.

Inhibition of hepatitis C virus replication in vitro by xanthohumol, a natural product present in hops.

Hepatitis C virus is a major cause of chronic liver disease worldwide. Xanthohumol, a prenylated flavonoid from hops, has various biological activities including an antiviral effect. It was previously characterized as a compound that inhibits bovine viral diarrhea virus, a surrogate model of hepatitis C virus. In the present work, xanthohumol was examined for its ability to inhibit hepatitis C virus replication in a cell culture system carrying replicating hepatitis C virus RNA replicon. 0.2 % DMSO and 500 units/mL interferon-alpha treatments were set as a negative and positive control, respectively. The inhibitory effect by xanthohumol was determined by the luciferase activity of the infected Huh7.5 cell lysates and the hepatitis C virus RNA levels in the culture. Xanthohumol at 3.53 µM significantly decreased the luciferase activity compared to the negative control (p < 0.01). Xanthohumol at 7.05 µM further decreased the luciferase activity compared to xanthohumol at 3.53 µM (p = 0.015). Xanthohumol at 7.05 µM or 14.11 µM achieved an inhibitory effect similar to that of interferon-alpha 2b (p > 0.05). Xanthohumol at 3.53 µM significantly reduced the hepatitis C virus RNA level compared to the negative control (p = 0.001). Although the results of xanthohumol at 7.05 µM had a higher variation, xanthohumol at the 7.05 µM and 14.11 µM decreased the hepatitis C virus RNA level to that achieved by interferon-alpha (p > 0.05). In conclusion, xanthohumol displays anti-hepatitis C virus activity in a cell culture system and may be potentially used as an alternative or complementary treatment against the hepatitis C virus.

Human parvovirus B19 DNA replication induces a DNA damage response that is dispensable for cell cycle arrest at phase G2/M.

Human parvovirus B19 (B19V) infection is highly restricted to human erythroid progenitor cells, in which it induces a DNA damage response (DDR). The DDR signaling is mainly mediated by the ATR (ataxia telangiectasia-mutated and Rad3-related) pathway, which promotes replication of the viral genome; however, the exact mechanisms employed by B19V to take advantage of the DDR for virus replication remain unclear. In this study, we focused on the initiators of the DDR and the role of the DDR in cell cycle arrest during B19V infection. We examined the role of individual viral proteins, which were delivered by lentiviruses, in triggering a DDR in ex vivo-expanded primary human erythroid progenitor cells and the role of DNA replication of the B19V double-stranded DNA (dsDNA) genome in a human megakaryoblastoid cell line, UT7/Epo-S1 (S1). All the cells were cultured under hypoxic conditions. The results showed that none of the viral proteins induced phosphorylation of H2AX or replication protein A32 (RPA32), both hallmarks of a DDR. However, replication of the B19V dsDNA genome was capable of inducing the DDR. Moreover, the DDR per se did not arrest the cell cycle at the G(2)/M phase in cells with replicating B19V dsDNA genomes. Instead, the B19V nonstructural 1 (NS1) protein was the key factor in disrupting the cell cycle via a putative transactivation domain operating through a p53-independent pathway. Taken together, the results suggest that the replication of the B19V genome is largely responsible for triggering a DDR, which does not perturb cell cycle progression at G(2)/M significantly, during B19V infection.

Molecular characterization of the newly identified human parvovirus 4 in the family Parvoviridae.

Human parvovirus 4 (PARV4) is an emerging human virus, and little is known about the molecular aspects of PARV4 apart from its incomplete genome sequence, which lacks information of the termini. We analyzed the gene expression profile of PARV4 using a nearly full-length HPV4 genome in a replication competent system in 293 cells. We found that PARV4 utilizes two promoters to transcribe non-structural protein- and structural protein-encoding mRNAs, respectively, which were polyadenylated at the right end of the genome. Three major proteins, including the large non-structural protein NS1a, whose mRNA is spliced, and capsid proteins VP1 and VP2, were detected. Additional functional analysis of the NS1a revealed its capability to induce cell cycle arrest at G2/M phase in ex vivo-generated human hematopoietic stem cells. Taken together, our characterization of the molecular features of PARV4 suggests that PARV4 represents a new genus in the family Parvoviridae.

Development of one-step SYBR Green real-time RT-PCR for quantifying bovine viral diarrhea virus type-1 and its comparison with conventional RT-PCR.

BACKGROUND: Bovine viral diarrhea virus (BVDV) is a worldwide pathogen in cattle and acts as a surrogate model for hepatitis C virus (HCV). One-step real-time fluorogenic quantitative reverse transcription polymerase chain reaction (RT-PCR) assay based on SYBR Green I dye has not been established for BVDV detection. This study aims to develop a quantitative one-step RT-PCR assay to detect BVDV type-1 in cell culture. RESULTS: One-step quantitative SYBR Green I RT-PCR was developed by amplifying cDNA template from viral RNA and using in vitro transcribed BVDV RNA to establish a standard curve. The assay had a detection limit as low as 100 copies/ml of BVDV RNA, a reaction efficiency of 103.2%, a correlation coefficient (R2) of 0.995, and a maximum intra-assay CV of 2.63%. It was 10-fold more sensitive than conventional RT-PCR and can quantitatively detect BVDV RNA levels from 10-fold serial dilutions of titrated viruses containing a titer from 10(-1) to 10(-5) TCID50, without non-specific amplification. Melting curve analysis showed no primer-dimers and non-specific products. CONCLUSIONS: The one-step SYBR Green I RT-PCR is specific, sensitive and reproducible for the quantification of BVDV in cell culture. This one-step SYBR Green I RT-PCR strategy may be further optimized as a reliable assay for diagnosing and monitoring BVDV infection in animals. It may also be applied to evaluate candidate agents against HCV using BVDV cell culture model.

Altered TNF-α and IFN-γ levels associated with PD1 but not TNFA polymorphisms in patients with chronic HBV infection.

Production of tumor necrosis factor (TNF)-α and interferon (IFN)-γ, two important cytokines involved in the immune responses to hepatitis B virus (HBV) infection, may be influenced by gene polymorphisms of TNFA and PD1. This study determined the associations of serum TNF-α and IFN-γ levels with TNFA promoter -308 G/A and -238 G/A and PD1 -606 G/A and +8669 G/A polymorphisms in chronic HBV patients and healthy controls. The results showed that TNFA polymorphisms had no association with TNF-α and IFN-γ levels. However, patients with PD1 -606 AA genotype had lower TNF-α and IFN-γ levels. HBV infection in patients with PD1 +8669 GG genotype altered TNF-α to higher levels compared with controls. HBV patients with PD1 -606A/+8669A or -606G/+8669A haplotype tended to have significantly lower or higher TNF-α and IFN-γ levels, respectively. Combined with the lower frequency of PD1 +8669 GG genotype in HBV patients and the minor contribution of PD1 -606 G allele to the protective role of PD1 +8669 G allele, it is indicated that PD1 -606 G allele in a haplotype with PD1 +8669 G allele may have strong inhibitory effect on programmed cell death-1 (PD-1) function and thus reduce its negative impact on T-cell activation and function, leading to higher cytokines secretion and exhibiting a protective role, while the minor predisposing role of PD1 -606 AA genotype to chronic HBV infection may be incurred by decreasing the inhibitory effect on PD-1 function.

Parvovirus B19 infection of human primary erythroid progenitor cells triggers ATR-Chk1 signaling, which promotes B19 virus replication.

Human parvovirus B19 (B19V) infection is restricted to erythroid progenitor cells of the human bone marrow. Although the mechanism by which the B19V genome replicates in these cells has not been studied in great detail, accumulating evidence has implicated involvement of the cellular DNA damage machinery in this process. Here, we report that, in ex vivo-expanded human erythroid progenitor cells, B19V infection induces a broad range of DNA damage responses by triggering phosphorylation of all the upstream kinases of each of three repair pathways: ATM (ataxia-telangiectasi mutated), ATR (ATM and Rad3 related), and DNA-PKcs (DNA-dependent protein kinase catalytic subunit). We found that phosphorylated ATM, ATR, and DNA-PKcs, and also their downstream substrates and components (Chk2, Chk1, and Ku70/Ku80 complex, respectively), localized within the B19V replication center. Notably, inhibition of kinase phosphorylation (through treatment with either kinase-specific inhibitors or kinase-specific shRNAs) revealed requirements for signaling of ATR and DNA-PKcs, but not ATM, in virus replication. Inhibition of the ATR substrate Chk1 led to similar levels of decreased virus replication, indicating that signaling via the ATR-Chk1 pathway is critical to B19V replication. Notably, the cell cycle arrest characteristic of B19V infection was not rescued by interference with the activity of any of the three repair pathway kinases.

Granulocyte colony-stimulating factor treatment ameliorates liver injury and improves survival in rats with D-galactosamine-induced acute liver failure.

Only liver transplantation is currently available therapy for the patients with acute liver failure (ALF). This study was designed to determine whether administration of granulocyte colony-stimulating factor (G-CSF) has therapeutic efficacy in animals with ALF. Female Sprague-Dawley (SD) rats were intraperitoneally injected with a single dose of d-galactosamine (d-GalN, 1.4g/kg) to induce ALF. After 2h, the rats were randomized to receive G-CSF (50µg/kg/day), or saline vehicle injection for 5 days. Rats were observed for survival and assessed for liver injury by serum alanine transaminase (ALT) measurement and histological analysis. CD34+ cells in bone marrow were assessed by flow cytometry. CD34+ cells and Ki-67+ hepatocytes in liver tissue were evaluated by immunohistochemistry. In the ALF model, 5-day survival after d-GalN injection was 33.3% (10/30), while G-CSF administration following d-GalN resulted in 53.3% (16/30) survival (p=0.027). G-CSF treated rats had lower ALT level and less hepatic injury compared with saline vehicle rats. The increases of CD34+ cells in bone marrow and liver tissue and Ki-67+ cells in liver tissue in G-CSF treated rats were higher than those in saline rats. No correlation was observed between CD34+ cells and Ki-67+ hepatocytes in liver tissue in both G-CSF and vehicle rats. It is suggested that G-CSF increases survival rate, decreases liver injury and enhances hepatocyte proliferation in rats with d-GalN-induced ALF possibly through actions including but not limiting to CD34+ cell mobilization, and that G-CSF may be of potential value in treating ALF.

Acute kidney injury in patients with hemorrhagic fever with renal syndrome caused by Hantaan virus: comparative evaluation by RIFLE and AKIN criteria.

Acute kidney injury (AKI) is one of the most prominent characteristics of hemorrhagic fever with renal syndrome (HFRS) caused by Hantaan virus. The present study evaluated the incidence and severity of AKI classified by both the RIFLE and AKIN criteria in 120 HFRS patients at 48 h and 1 week of the patient admission. The agreements between RIFLE and AKIN and RIFLE and AKIN defined by serum creatinine (AKINc and RIFLEc) were examined by Kappa statistics. AKI occurred in 79.2% and 82.5% at 48 h and in 84.2% and 89.2% at 1 week of admission by RIFLE and AKIN criteria, respectively. RIFLE and AKIN showed very good agreement in classifying AKI at 48 h and 1 week of admission (κ > 0.900). RIFLE and RIFLEc and AKIN and AKINc at 48 h and 1 week of admission had almost perfect agreement (κ > 0.900). The classifications of RIFLE and RIFLEc and AKIN and AKINc at 48 h and 1 week were in good agreement (κ > 0.650). AKI classifications by RIFLE and AKIN were associated with mortality, occurrence of complications, and length of hospital stay. We conclude that AKI occurs in nearly 90% of HFRS patients during the disease course. RIFLE and AKIN classify AKI in HFRS with similar sensitivity. RIFLEc and AKINc may be used as alternatives of standard RIFLE and AKIN in the settings of general wards. The AKI classifications defined at 48 h of admission have predictive value for HFRS disease progression and severity.

CTLA-4 exon 1 +49 polymorphism alone and in a haplotype with -318 promoter polymorphism may confer susceptibility to chronic HBV infection in Chinese Han patients.

Cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) plays a pivotal role in regulating T cell activation, which is believably critical for the outcome of hepatitis B virus (HBV) infection. The expression and function of CTLA-4 may be affected by gene polymorphisms. This study investigated the influence of CTLA-4 polymorphisms on disease susceptibility in Chinese Han patients with chronic HBV infection. CTLA-4 +49A/G and -318C/T polymorphisms were evaluated by DNA amplification with polymerase chain reaction followed by the restriction fragment length polymorphism analysis. The patients with chronic HBV infection had higher frequencies of genotype AA and allele A of CTLA-4 +49A/G polymorphism. The haplotype +49A-318C was significantly over-represented (P < 0.001) and haplotype +49G-318C under-represented (P = 0.006) in the patients. The +49GG genotype was more frequent (P = 0.009) and +49A allele was less frequent in patients with lower ALT levels (P = 0.012) in HBeAg positive chronic hepatitis B. It is indicated that CTLA-4 +49A/G polymorphism alone and in a haplotype with -318C allele may confer susceptibility to chronic HBV infection in Chinese Han patients.

Association of polymorphisms of programmed cell death-1 gene with chronic hepatitis B virus infection.

Programmed cell death-1 (PD-1) plays a critical role in regulating T-cell function during hepatitis B virus (HBV) infection. The present study investigated the relationships between the polymorphisms of the PD-1 gene and the susceptibility to chronic HBV infection. Single nucleotide polymorphisms (SNPs) in PD-1 gene at positions -606G/A (PD-1.1) and +8669 G/A (PD-1.6) were analyzed by bidirectional PCR amplification of specific alleles (Bi-PASA) in 198 chronic HBV patients and 280 controls. Although the genotype and allele frequencies of PD-1.1 were not different between chronic HBV patients and controls, the genotype and allele frequencies of PD-1.6 were significantly different. PD-1.6 GG genotype and the combination of genotypes with G allele were less frequent in HBV patients than in controls (p = 0.007 and p = 0.031, respectively). The allele G was also less frequent in patients than in controls (p = 0.006). Haplotype PD-1.1G/PD-1.6G was less frequent in patients than in controls (p = 0.001). Cirrhosis patients had a lower frequency of PD-1.6 G allele compared with controls (p = 0.007). Our findings, firstly reporting the association between PD-1 polymorphism and HBV infection, suggest that PD-1 gene may be one of the genes predisposing to chronic HBV infection and disease progression.

Role of erythropoietin receptor signaling in parvovirus B19 replication in human erythroid progenitor cells.

Parvovirus B19 (B19V) infection is highly restricted to human erythroid progenitor cells. Although previous studies have led to the theory that the basis of this tropism is receptor expression, this has been questioned by more recent observation. In the study reported here, we have investigated the basis of this tropism, and a potential role of erythropoietin (Epo) signaling, in erythroid progenitor cells (EPCs) expanded ex vivo from CD34(+) hematopoietic cells in the absence of Epo (CD36(+)/Epo(-) EPCs). We show, first, that CD36(+)/Epo(-) EPCs do not support B19V replication, in spite of B19V entry, but Epo exposure either prior to infection or after virus entry enabled active B19V replication. Second, when Janus kinase 2 (Jak2) phosphorylation was inhibited using the inhibitor AG490, phosphorylation of the Epo receptor (EpoR) was also inhibited, and B19V replication in ex vivo-expanded erythroid progenitor cells exposed to Epo (CD36(+)/Epo(+) EPCs) was abolished. Third, expression of constitutively active EpoR in CD36(+)/Epo(-) EPCs led to efficient B19V replication. Finally, B19V replication in CD36(+)/Epo(+) EPCs required Epo, and the replication response was dose dependent. Our findings demonstrate that EpoR signaling is absolutely required for B19V replication in ex vivo-expanded erythroid progenitor cells after initial virus entry and at least partly accounts for the remarkable tropism of B19V infection for human erythroid progenitors.

Elevated sICAM-1 levels in patients with hemorrhagic fever with renal syndrome caused by Hantaan virus.

Increased vascular permeability and vascular leakage are characteristic pathological changes in hemorrhagic fever with renal syndrome (HFRS). Vascular endothelial cells are the main targets of Hantaan virus, the etiological agent of the severe form of HFRS. Hantaan virus can induce extensive damage of small blood vessels and capillaries. In vitro infection of human umbilical vein endothelial cells by Hantaan virus can induce the expression of intercellular adhesion molecule-1 (ICAM-1). The involvement of this molecule is implied in human HFRS. In the present study, serum-soluble ICAM-1 (sICAM-1) levels were determined and their relationships with the clinical course and disease severity were investigated in 112 HFRS patients and 30 healthy controls. The results showed that the serum levels of sICAM-1 in HFRS patients at fever, hypotensive, oliguric, and polyuric phases were significantly higher than those in controls (p < 0.001). However, no significant differences between the serum concentrations of sICAM-1 in the milder and more severe groups of patients were observed (p > 0.05). It is suggested that sICAM-1 was involved in the progression of HFRS. Time-dependent determinations of sICAM-1 levels may be indicators for the progression of disease, and elevated levels of sICAM-1 were not suggested to be correlated to disease severity.

Characterization of the gene expression profile of human bocavirus.

We have generated a quantitative transcription profile of human bocavirus type 1 (HBoV1) by transfecting a nearly full-length clone in human lung epithelial A549 cells as well as in a replication competent system in 293 cells. The overall transcription profile of HBoV1 is similar to that of two other members of genus Bocavirus, minute virus of canines and bovine parvovirus 1. In particular, a spliced NS1-transcript that was not recognized previously expressed the large non-structural protein NS1 at approximately 100kDa; and the NP1-encoding transcripts were expressed abundantly. In addition, the protein expression profile of human bocavirus type 2 (HBoV2) was examined in parallel by transfection of a nearly full-length clone in A549 cells, which is similar to that of HBoV1. Moreover, our results showed that, unlike human parvovirus B19 infection, expression of the HBoV1 proteins only does not induce cell cycle arrest and apoptosis of A549 cells.

Higher pretherapy and significant decrease during the first 12 months of therapy in serum laminin levels may associate with hepatitis B e antigen seroconversion in chronic hepatitis B patients treated with lamivudine.

Laminin participates in regulating immune response in addition to being a biomarker of liver fibrosis. Lamivudine has been shown to be able to restore cytotoxic T-cell response in chronic hepatitis B. In this study, fifty-two patients with HBeAg-positive chronic hepatitis B received lamivudine treatment for more than 12 months. Serum laminin levels were determined at baseline and during treatment and analyzed regarding treatment responses at the end of 12 months of therapy. The results showed that laminin levels at 12 months of treatment in patients who lost HBeAg were significantly lower compared with baseline (P = 0.001). The baseline laminin levels were higher in HBeAg seroconversion group than those without seroconversion (P = 0.037). Compared with baseline, the levels of serum laminin in HBeAg seroconversion group showed significant decrease (P = 0.001). It is concluded that higher pretherapy and significant decrease during the first 12 months of therapy in laminin levels may associate with HBeAg seroconversion in chronic hepatitis B patients treated with lamivudine, indicating the possible novel information of laminin for clinical reference.

Increased serum fibronectin levels in patients with hemorrhagic fever with renal syndrome.

BACKGROUND: In view of the role of fibronectin in adhesion, signal transduction pathways and the infectious disease process, changes in serum fibronectin levels may influence disease evolution and severity in patients with hemorrhagic fever with renal syndrome (HFRS). METHODS: The levels of fibronectin were measured in serum samples from 112 patients with HFRS at various phases, and 30 healthy individuals were monitored as controls. RESULTS: The serum levels of fibronectin in patients with HFRS at all clinical phases were higher than those in the controls, with the levels of patients at the fever, oliguric and polyuric phases of disease significantly different from controls (P < 0.01). The serum fibronectin concentration in the patients with more severe clinical disease types was higher than that in those with milder types. The serum fibronectin level in the more severe patient group was significantly higher than that in milder patient group at the oliguric phase (P < 0.05). CONCLUSIONS: Serum fibronectin concentration in patients with HFRS was increased and associated with disease phases and severity, suggesting the value of detection of fibronectin levels for evaluating HFRS disease progression and severity.

G-CSF enhanced SDF-1 gradient between bone marrow and liver associated with mobilization of peripheral blood CD34+ cells in rats with acute liver failure.

The role of stromal cell-derived factor-1 (SDF-1) in modulating massive liver damage is not well known. In this study, expression of SDF-1 in bone marrow and liver was investigated in rats with acute liver failure (ALF) when mobilized using granulocyte colony-stimulating factor (G-CSF). ALF was induced in rats by D-galactosamine (D-GalN). Starting after 2 hours following D-GalN induction, the animals were injected with G-CSF 50 microg/kg daily or saline as placebo for 5 days. The percentages of CD34+ cells in peripheral blood and the expression of SDF-1 in bone marrow and liver were then determined. The percentages of peripheral CD34+ cells demonstrated a transient increase in placebo rats following D-GalN induction and a significant increase in rats after G-CSF administration. SDF-1 expression showed a transient decrease in bone marrow and a transient increase in liver tissue from placebo rats. However, a significant decrease of SDF-1 expression in bone marrow and a remarkable increase in liver tissue were observed in animals from the G-CSF group. It was concluded that G-CSF can enhance the reduced expression of SDF-1 in bone marrow and increased expression in liver in ALF rats, forming a greater SDF-1 gradient, and chemoattracting CD34+ cells' migration from bone marrow to an injured liver.

Inhibition of bovine viral diarrhea virus in vitro by xanthohumol: comparisons with ribavirin and interferon-alpha and implications for the development of anti-hepatitis C virus agents.

Xanthohumol (XN) is a natural compound with potential antiviral activity. In this study, the ability of XN to inhibit bovine viral diarrhea virus (BVDV), a surrogate model of hepatitis C virus (HCV), was investigated. The antiviral activity of XN was compared with that of ribavirin (RBV) and interferon (IFN)-alpha. The results showed that XN could inhibit BVDV induced cytopathic effects (CPE). At 1000 TCID(50) and 100 TCID(50), the values of 50% effective concentration (EC(50)) were 3.24+/-0.02 mg/l and 2.77+/-0.19 mg/l, respectively, and the therapeutic indices were >7.72 and >9.03, respectively. XN inhibited BVDV E2 expression and viral RNA levels in a dose-dependent manner. At 6.25mg/l, XN decreased the viral RNA from released virus by 3.83 log 10 at 1000 TCID(50) and to an undetectable level at 100 TCID(50), and decreased the viral RNA level in whole cell culture by 3.36 log 10 and 2.88 log 10 at 1000 TCID(50) and 100 TCID(50), respectively. The inhibitory activity of XN on CPE, BVDV E2 expression and viral RNA levels was stronger than that of RBV and weaker than that of IFN-alpha. These results indicate the need to investigate the anti-HCV potential of XN.