Significance of serum hepatitis C virus RNA levels in chronic hepatitis C

Hepatitis C virus (HCV) is the main cause of parenteral non-A, non-B hepatitis and serum can be tested for the virus itself by reverse-transcription polymerase chain amplification. What of the level of this viraemia? To find out if quantitative study of HCV RNA might be useful clinically we took advantage of participation in trials of interferon-alpha in patients with chronic HCV infection and applied a new assay, branched DNA (bDNA) signal amplification. Paired serum and liver biopsy specimens from 47 patients with confirmed chronic HCV infection and evidence of HCV RNA in their serum were studied. The quantitative bDNA assay (detection limit 350,000 equivalents/mL [eq/mL]) was positive in 34 sera (sensitivity 72%). Patients who acquired HCV infection by blood transfusion had a higher viraemia (median 2,701,000 eq/mL, n = 29) than health workers and intravenous drug users (635,000 eq/mL, n = 13; p < 0.01). Patients with a sustained complete response to interferon-alpha therapy had lower pre-treatment viraemia levels (median at bDNA cut-off, n = 11) than complete responders who relapsed after the drug was stopped (1,613,000 eq/mL, n = 15; p < 0.01) and non-responders (3,066,000 eq/mL, n = 20; p < 0.01). High viraemia levels were not related to the histological diagnosis but were associated with lobular inflammation, lymphoid aggregates, and bile-duct lesions. These findings indicate that mode of acquisition is an important determinant of HCV viraemia and that patients with low HCV viraemia levels are more likely to respond to interferon in a sustained fashion.

Association of diabetes mellitus and chronic hepatitis C virus infection

While patients with liver disease are known to have a higher prevalence of glucose intolerance, preliminary studies suggest that hepatitis C virus (HCV) infection may be an additional risk factor for the development of diabetes mellitus. To further study the correlation of HCV infection and diabetes, we performed a retrospective analysis of 1,117 patients with chronic viral hepatitis and analyzed whether age, sex, race, hepatitis B virus (HBV) infection, HCV infection, and cirrhosis were independently associated with diabetes. In addition, a case-control study was conducted to determine the seroprevalence of HCV infection in a cohort of 594 diabetics and 377 clinic patients assessed for thyroid disease. In the former study after the exclusion of patients with conditions predisposing to hyperglycemia, diabetes was observed in 21% of HCV-infected patients compared with 12% of HBV-infected subjects (P =.0004). Multivariate analysis revealed that HCV infection (P =.02) and age (P =.01) were independent predictors of diabetes. In the diabetes cohort, 4.2% of patients were found to be infected with HCV compared with 1.6% of control patients (P =.02). HCV genotype 2a was observed in 29% of HCV-RNA-positive diabetic patients versus 3% of local HCV-infected controls (P <.005). In conclusion, the data suggest a relatively strong association between HCV infection and diabetes, because diabetics have an increased frequency of HCV infection, particularly with genotype 2a. Furthermore, it is possible that HCV infection may serve as an additional risk factor for the development of diabetes, beyond that attributable to chronic liver disease alone.

Kendrick mass defect spectrum: a compact visual analysis for ultrahigh-resolution broadband mass spectra

At currently achievable Fourier transform ion cyclotron resonance broadband mass spectrometry resolving power (m/deltam50% > 350,000 for 200 < m/z < 1,000), it would be necessary to spread out a conventional mass spectrum over approximately 200 m in order to provide visual resolution of the most closely resolved peaks. Fortunately, there are natural gaps in a typical mass spectrum, spaced 1 Da apart, because virtually no commonly encountered elemental compositions yield masses at those values. Thus, it is possible to break a broadband mass spectrum into 1-Da segments, rotate each segment by 90 degrees, scale each segment according to its mass defect (i.e., difference between exact and nominal mass), and then compress the spacing between the segments to yield a compact display. For hydrocarbon systems, conversion from IUPAC mass to "Kendrick" mass (i.e., multiplying each mass by 14.00000/14.01565) further simplifies the display by rectilinearizing the peak patterns. The resulting display preserves not only the "coarse" spacings (e.g., approximately 1 Da between odd and even masses, corresponding to either even vs odd number of nitrogens or 12C(c) vs 12C(c-1)13C1 elemental compositions of the same molecule; approximately 2-Da separations, corresponding to a double bond or ring; approximately 14 Da separations, corresponding to one CH2 group) but also the "fine structure" (i.e., different mass defects for different elemental compositions) across each 1-Da segment. The method is illustrated for experimental electrospray ionization FTICR ultrahigh-resolution mass spectra of a petroleum crude oil. Several thousand elemental compositions may be resolved visually in a single one-page two-dimensional display, and various compound families-class (NnOoSs), type (Z in C(c)H2(c+z)NnOoSs), and alkylation series-may be identified visually as well.

A longitudinal analysis of hepatitis C virus replication following liver transplantation

BACKGROUND & AIMS

The pathogenesis of graft injury in liver transplant recipients with recurrent hepatitis C virus (HCV) infection remains poorly understood. In this study, the relationship between HCV replication, genotype, and the evolution of graft damage was investigated.

METHODS

HCV RNA was quantified in 184 protocol sera from 25 patients transplanted for HCV cirrhosis. HCV isolates were genotyped, and hepatic expression of core and NS4 antigens was sought in protocol allograft biopsy specimens.

RESULTS

Acute lobular hepatitis was accompanied by a steep increase in HCV RNA levels and the appearance of core and NS4 antigens in the graft. Methylprednisolone treatment for acute rejection led to a 4-100-fold increase in serum HCV RNA. At the end of follow-up, HCV RNA levels were 3-112 times pretransplant levels and were higher in patients with more severe hepatitis. Progressive liver damage developed in 7 of 14 patients with HCV genotype 1b and in 1 of 11 patients infected with other genotypes (P = 0.03).

CONCLUSIONS

Peak viremia levels and the initial detection of HCV antigens in hepatocytes suggests increased viral replication at the time of acute HCV hepatitis in the graft. Genotype 1b and higher viremia levels were associated with more severe chronic graft damage.

Application of six hepatitis C virus genotyping systems to sera from chronic hepatitis C patients in the United States

Serum samples from 139 US patients with chronic hepatitis C virus (HCV) infection were studied using six different genotyping systems, including both molecular and serologic methods, to determine the applicability of these approaches and the prevalence of various HCV subtypes. The concordance of genotyping results based on the various systems (except for core polymerase chain reaction genotyping) was good (93.5%). Subtypes 1a and 1b were prevalent (37.4%). Subtypes 2a (2.2%), 2b (8.6%), and 3a (5.8%) were less common. HCV genotypes could not be determined in 3.4%-16.5% of samples depending on the method used. HCV type 2 was associated with greater histologic activity but lower serum HCV RNA levels (P < .05), whereas type 3 was associated with lower serum alanine aminotransferase levels (P < .05). These data demonstrate a high concordance between HCV genotyping systems and provide a foundation for comparison of genotyping data between studies using different systems. HCV types 1a and 1b are both prevalent in the United States.

Distribution of hepatitis C virus genotypes determined by line probe assay in patients with chronic hepatitis C seen at tertiary referral centers in the United States. Hepatitis Interventional Therapy Group

OBJECTIVE

To 1) verify the validity of a new line probe assay for hepatitis C virus (HCV) genotyping and 2) determine the distribution of HCV genotypes and the association between HCV genotype and clinical variables in patients with chronic hepatitis C seen in tertiary referral centers in the United States.

DESIGN

Retrospective cross-sectional analysis.

PATIENTS

438 patients with chronic hepatitis C from 10 tertiary referral centers.

MEASUREMENTS

The validity of the line probe assay was first verified against a panel of serum specimens that had previously been characterized by six different HCV genotyping methods. Specimens from all 438 patients were then genotyped using this line probe assay. The associations between HCV genotype and clinical variables were examined using analysis of variance. Pairwise testing was used when the F test showed a statistically significant difference. Nonparametric alternatives were used for variables for which normality could not be assumed.

RESULTS

The line probe assay was quick and reproducible, and it showed good concordance with other tests. In our sample, the proportions of patients with HCV types 1, 2, 3, and 4 were 71.5%, 13.5%, 5.5%, and 1.1%, respectively. Subtypes 1a and 1b were seen in approximately equal proportions of patients with HCV type 1. Mixed infection was detected in 3.7% of specimens, and 4.8% of specimens either had negative results on polymerase chain reaction or could not be typed. A higher proportion of patients with HCV type 1 than of patients with HCV-type 1 had acquired HCV through transfusion of blood products (50% compared with 25%; P < 0.001). Patients with HCV type 1 also had a longer estimated duration of infection compared with patients with HCV type 3 (P = 0.004) and type 4 (P = 0.049). Disease activity did not differ among patients infected with HCV types 1, 2, or 3. Levels of viremia were similar in patients with HCV types 1, 2, or 3, but patients with HCV type 4 had a lower level of viremia than did patients with HCV type 1 (P = 0.047).

CONCLUSIONS

The line probe assay can be used in patients with chronic HCV infection in the United States. In patients with chronic hepatitis C referred to tertiary centers in the United States, type 1 is the most common HCV genotype. Disease activity and viremia levels do not differ among patients chronically infected with HCV types 1, 2, or 3.

Transforming growth factor-beta 1 in chronic hepatitis C

Transforming growth factor-beta 1 (TGF-beta 1) has been implicated in mediating hepatic fibrogenesis and is known to have negative regulatory effects on the immune system. To analyse the effects of TGF-beta 1 in chronic HCV, serum samples were prospectively collected from 88 chronic hepatitis C virus (HCV) patients and 34 healthy controls. Total and biologically active TGF-beta 1, interleukin (IL)-4 and IL-10 were measured by enzyme-linked immunosorbent assay (ELISA). HCV RNA levels were quantified by branched DNA signal amplification pathway (bDNA), and HCV genotypes were determined by restriction fragment length polymorphism (RFLP) based on the 5'-untranslated region (UTR). Histological diagnosis was available in 87 patients, and liver sections from 80 other HCV patients were evaluated for hepatic expression of TGF-beta 1 using immunohistochemistry. Patients with chronic HCV infection had a higher level of TGF-beta 1, both total (817 +/- 464 ng ml-1) and biologically active forms (520 +/- 370 pg ml-1), compared with controls (total TGF-beta 1 183 +/- 105 ng ml-1, P < 0.001; active TGF-beta 1 290 +/- 140 pg ml-1, P < 0.01). There was no correlation between either total or biologically active TGF-beta 1 and clinical variables (age, gender, duration), liver biochemistry (serum alanine aminotransferase) or virological (HCV RNA level, genotype) parameters but there was a correlation between total TGF-beta 1 and Knodell scores (P = 0.03, n = 54). However, when individual histological parameters were analysed, only the fibrosis score showed significant correlation (P = 0.04, n = 54). Immunohistochemistry revealed that 62% of HCV patients had TGF-beta 1 present in sinusoidal cells. No correlation existed between hepatic expression of TGF-beta 1 and any histological parameters. A trend existed towards a correlation between total TGF-beta 1 and IL-4 (P = 0.059, n = 74) but not with IL-10. Therefore, the TGF-beta 1 system is activated in chronic HCV infection and may contribute towards hepatic fibrogenesis; in addition, the TGF-beta 1 system may interact with IL-4.

Clinical implications of viral quasispecies heterogeneity in chronic hepatitis C

To determine the clinical significance of viral quasispecies heterogeneity, 59 patients with chronic hepatitis C were studied using singlestranded conformational polymorphism (SSCP) analysis of the HCV E2 hypervariable region 1 (HVR1); of these, 48 were subsequently treated with interferon-alpha. The SSCP method was validated using clones of known nucleotide sequence. HVR1 was amplified in 54 of 59 (92%) patients. The median number of SSCP bands per sample was 6 (range: 2-12). Increased quasispecies heterogeneity correlated with the estimated duration of HCV infection (P < 0.05), parenteral-acquired HCV infection (vs. sporadic, P < 0.05), serum HCV RNA levels (P < 0.05), and HCV genotype 1 infection (P < 0.05), but not with age, serum AST, ALT, or Knodell score. Patients who had complete and sustained response to interferon-alpha (n = 11) had lower pre-treatment quasispecies heterogeneity compared to patients who had complete response with relapse (n = 18, P < 0.05) or no complete response (n = 16, P < 0.01). However, multivariate analysis revealed that HCV viremia was a stronger predictor of response to interferon-alpha. These findings indicate that the estimated duration of HCV carriage, serum HCV RNA levels, and HCV type 1 are important determinants for the evolution of HCV quasispecies heterogeneity; and that increased HCV quasispecies heterogeneity is another marker associated with a poor subsequent response to interferon-alpha.

MiR-873 regulates ERα transcriptional activity and tamoxifen resistance via targeting CDK3 in breast cancer cells

miRNAs (microRNAs) are frequently and aberrantly expressed in many cancers. MiR-873 has been revealed to be downregulated in colorectal cancer and glioblastoma. However, its function remains unclear. Here we report that miR-873 is downregulated in breast tumor compared with normal tissue. Enforced expression of miR-873 decreases the transcriptional activity of ER (estrogen receptor)-α but not ERβ through the modulation of ERα phosphorylation in ER-positive breast cancer cells. We also found that miR-873 inhibits breast cancer cell proliferation and tumor growth in nude mice. Reporter gene assays revealed cyclin-dependent kinase 3 (CDK3) as a direct target of miR-873. CDK3 was shown to be overexpressed in breast cancer and phosphorylate ERα at Ser104/116 and Ser118. Furthermore, we found that Mir-873 inhibits ER activity and cell growth via targeting CDK3. Interestingly, miR-873 was observed to be downregulated in tamoxifen-resistant MCF-7/TamR cells, while CDK3 is overexpressed in these cells. More importantly, re-expression of miR-873 reversed tamoxifen resistance in MCF-7/TamR cells. Our data demonstrate that miR-873 is a novel tumor suppressor in ER-positive breast cancer and a potential therapeutic approach for treatment of tamoxifen-resistant breast cancer.

Intrinsically patterned two-dimensional materials for selective adsorption of molecules and nanoclusters

Two-dimensional (2D) materials have been studied extensively as monolayers, vertical or lateral heterostructures. To achieve functionalization, monolayers are often patterned using soft lithography and selectively decorated with molecules. Here we demonstrate the growth of a family of 2D materials that are intrinsically patterned. We demonstrate that a monolayer of PtSe₂ can be grown on a Pt substrate in the form of a triangular pattern of alternating 1T and 1H phases. Moreover, we show that, in a monolayer of CuSe grown on a Cu substrate, strain relaxation leads to periodic patterns of triangular nanopores with uniform size. Adsorption of different species at preferred pattern sites is also achieved, demonstrating that these materials can serve as templates for selective self-assembly of molecules or nanoclusters, as well as for the functionalization of the same substrate with two different species.

Efficacy and safety of catnip (Nepeta cataria) as a novel filth fly repellent

Catnip (Nepeta cataria) is known for its pseudo-narcotic effects on cats. Recently, it has been reported as an effective mosquito repellent against several Aedes and Culex species, both topically and spatially. Our laboratory bioassays showed that catnip essential oil (at a dosage of 20 mg) resulted in average repellency rates of 96% against stable flies, Stomoxys calcitrans (L.) and 79% against houseflies, Musca domestica (L.), respectively. This finding suggested that the application of repellent could be used as part of filth fly management. Further evaluations of catnip oil toxicity were conducted to provide a broad-spectrum safety profile of catnip oil use as a potential biting and nuisance insect repellent in urban settings. Acute oral, dermal, inhalation, primary dermal and eye irritation toxicity tests were performed. The acute oral LD(50) of catnip oil was found to be 3160 mg/kg body weight (BW) and 2710 mg/kg BW in female and male rats, respectively. The acute dermal LD50 was > 5000 mg/kg BW. The acute inhalation LD50 was observed to be > 10,000 mg/m3. Primary skin irritation tested on New Zealand white rabbits showed that catnip oil is a moderate irritant. Catnip oil was classified as practically non-irritating to the eye. In comparison with other U.S. Environmental Protection Agency-approved mosquito repellents (DEET, picaridin and p-menthane-3,8-diol), catnip oil can be considered as a relatively safe repellent, which may cause minor skin irritation.

Accuracy of aneroid sphygmomanometers in clinical usage: University of Michigan experience

BACKGROUND

Aneroid manometers are frequently used to measure blood pressure. Aneroid manometers have moving parts that are subject to fatigue. The accuracy duration of the aneroid devices, like most digital devices, is unstudied. It has been accepted that if the aneroid device does not rest at '0' it is inaccurate, but how often is the device inaccurate when it does rest at '0'?

METHODS

A Universal Biometer DPM-III measuring unit was used for all of the measurements at 10 University of Michigan Health System sites. A total of 136 aneroid manometers were tested. Two additional aneroid devices were not tested, as the needle did not start within '0'. Static pressure measurements were made at nine levels for all devices: 50, 80, 90, 100, 120, 150, 200 and 250mmHg.

RESULTS

The average difference of the nine pressure settings of the whole group was 0.2+/-0.31 (95% confidence interval 0.1-0.2) mmHg. The largest number of devices that were not calibrated within +/-3mmHg was seen at the 150mmHg setting with six (4.4%) of the devices failing. If an accuracy standard of +/-2mmHg was used, the largest number of devices failed at 250mmHg (22 devices, 16.2%). The largest number of devices that were inaccurate was manufactured 6 years prior to testing and was from two sites.

CONCLUSIONS

Aneroid devices were accurate. A yearly calibration programme should be performed and a +/-2mmHg standard should be used. Portable aneroid manometers may need to be more frequently calibrated due to the trauma associated with dropping.

Significance of antibody to the host cellular gene derived epitope GOR in chronic hepatitis C virus infection

The humoral response to the host cellular gene-derived epitope GOR (anti-GOR) was reported to be associated with chronic hepatitis C virus (HCV) infection. To determine the prevalence and clinical significance of anti-GOR, sera from 31 patients (M/F, 19/12, age 30-72) with chronic HCV infection (anti-HCV+ in 30, HCV-RNA+ by PCR in 31) were tested for anti-GOR by enzyme immunoassay. Results were correlated with clinical, biochemical and histological features, and the subsequent response to interferon-alpha therapy (a complete response was defined as normalization of serum ALT at the completion of therapy; a sustained response was defined as having normal serum liver biochemistry during the entire follow-up period). Anti-GOR was detected in 21 patients [67.7%, median optical density (OD) reading 2.634, range 0.865-3.000, cut-off value 0.300]. There was no correlation between the presence or the OD reading of anti-GOR and the clinical features (sex, age, mode of acquisition), biochemical tests (serum ALT, AST, alkaline phosphatase and albumin levels), autoimmune markers [serum globulin levels, anti-nuclear antibody (+ at < 1:80 in 6/31 patients)], and their subsequent response to interferon-alpha therapy (complete response in anti-GOR+ patients: 13/21, anti-GOR-: 5/10, p = NS; sustained response in anti-GOR+ patients: 5/21, anti-GOR-: 2/10, p = NS). There was also no correlation between anti-GOR and the histological features including Knodell score and its components including periportal inflammation, portal inflammation and fibrosis, the presence of lymphoid aggregates, macrovesicular and microvesicular fat, multinucleated hepatocytes, dysplasia, sinusoidal activity or bile duct lesions.(ABSTRACT TRUNCATED AT 250 WORDS)

Hepatitis C virus mixed genotype infection in patients on haemodialysis

Hepatitis C virus (HCV) has been classified into different genotypes/subtypes with demonstrated clinical implications. Whether there is biological difference between genotypes is unknown. We determined HCV genotype in 120 anti-HCV-positive patients with end-stage renal disease and on haemodialysis, by both serological assay (which showed evidence of previous exposure) and by two molecular assays: restriction fragment length polymorphism (RFLP) and line-probe reverse hybridization (LiPA). In mixing experiments, RFLP and LiPA was able to detect the minor HCV genotypes (if present) in 5-30% and 1-2% of the viral population, respectively. Of the 120 patients studied, genotype-specific antibodies were detected in 50 (42%), and eight patients had reactivities to peptides derived from multiple genotypes (genotypes 1 and 2 and/or 3). Only genotype 1 infection was found by RFLP/LiPA in these eight patients with reactivities to multiple HCV genotypes. One-hundred and five of the 120 (88%) patients were positive for HCV RNA by reverse transcription-polymerase chain reaction (RT-PCR) analysis and 14 were found to have mixed genotype infection. Follow-up serum samples (4-21 months later) were available in five patients (genotype 1a with another genotype/subtype). All five patients had a reduced number of HCV genotypes detected during follow-up; four of the five patients still had detectable genotype 1a, and one patient lost genotype 1a and was positive for genotype 2b only. These data showed that HCV mixed infection can be reliably detected by molecular methods and, in patients with end-stage renal disease and mixed genotype infection, there is a trend that during follow-up, HCV genotype 1 may prevail, or 'take over' the genotype 2 and 3 infection.

Thyroid hormone coordinates respiratory control maturation and adenine nucleotide translocator expression in heart in vivo

BACKGROUND

The signal transduction mechanism linking mitochondrial ATP synthesis with cytosolic ATP utilization in heart changes during postnatal development in vivo. This maturational process occurs in parallel with accumulation of mitochondrial adenine nucleotide translocator (ANT), which provides a possible site for respiratory control. We postulated that thyroid hormone regulates these maturational processes.

METHODS AND RESULTS

We used (31)P MR spectroscopy to determine the relationship between myocardial high-energy phosphates, phosphocreatine, and ADP and oxygen consumption (MVO(2)) during epinephrine stimulation in 32- to 40-day-old lambs thyroidectomized after birth (THY) and age-matched controls. Steady-state protein and mRNA levels for ANT isoforms and beta-F(1)-ATPase were assessed from left ventricular tissues by Western and Northern blotting. With greater doses of epinephrine, THY attained lower peak MVO(2) than controls (P:<0.05). Controls maintained high-energy phosphate levels, unlike THY, which demonstrated significantly decreased phosphocreatine/ATP and increased cytosolic ADP despite lower peak MVO(2). No significant differences in beta-F(1)-ATPase protein or mRNA occurred between groups. However, ANT isoform mRNA levels were 2-fold greater and protein levels 4-fold greater in control hearts.

CONCLUSIONS

These data imply that the maturational shift away from ADP-mediated respiratory control is regulated by thyroid hormone in vivo. Specific thyroid-modulated increases in ANT mRNA and protein imply that this regulation occurs in part at a pretranslational level.

A hypoxia-inducible vigilant vector system for activating therapeutic genes in ischemia

Hypoxia represents an endogenous pathophysiological signal underlying cell growth, adaptation and death in a variety of diseases, including ischemic heart diseases, stroke and solid tumors. A vigilant vector system depends on a gene switch which can sense the hypoxia signal occurring in ischemic events and turn on/off protective gene expressions when necessary. This system uses the oxygen-dependent degradation domain derived from hypoxia-inducible factor 1alpha as the hypoxia sensor and a double-vector system as signal amplifier. For treating ischemic heart diseases, a cardiac-specific MLC-2v promoter is used to deliver transgenes specifically to the heart. When tested in cardiomyocyte cultures, it produced a rapid and robust gene induction upon exposure to low oxygen. In a mouse model for myocardial infarction, the vigilant vectors turned on therapeutic genes such as heme oxygenase-1 in response to ischemia, significantly reduced apoptosis in the infarct area and improved cardiac functions. The hypoxia-regulated gene transfer afforded by the vigilant vectors may provide a powerful tool for delivering therapeutic proteins specifically to ischemic tissues with optimal physiological control.

Fundamentals of tandem mass spectrometry: a dynamics study of simple C-C bond cleavage in collision-activated dissociation of polyatomic ions at low energy

The loss of methyl radical in collision-activated dissociation (CAD) of acetone and propane molecular ions has been studied at low energy using a tandem hybrid mass spectrometer. Although the two processes are very similar chemically and energetically, very different dynamical features are observed. Acetyl ions from acetone ion are predominantly backward-scattered, with intensity maxima lying inside and outside the elastic scattering circle, confirming our previous observation that electronically excited states are important in low-energy acetone CAD. Ethyl ions from propane ion show a forward-scattered peak maximum at a nonzero scattering angle, which is consistent with generally accepted models for vibrational excitation and redistribution of energy before dissociation. Both processes demonstrate that CAD at low energy proceeds via small-impact-parameter collisions with momentum transfer. Comparison of the present results with higher energy CAD dynamics studies and earlier work leads to some tentative general conclusions about energy transfer in these processes.

Modulation of hepatitis C virus quasispecies heterogeneity by interferon-alpha and ribavirin therapy

To determine the effects of interferon-alpha (IFN-alpha) and ribavirin therapy on hepatitis C virus (HCV) quasispecies heterogeneity, 29 patients with chronic HCV infection treated with either IFN-alpha (n = 15), ribavirin (n = 7) or placebo (n = 7) were studied. HCV quasispecies heterogeneity was determined by single-strand conformational polymorphism (SSCP) analysis of the HCV E2 hypervariable region 1 (HVR1). For patients receiving IFN-alpha, HVR1 was amplified in 14 of 15 patients before, and in six of seven patients after therapy. After controlling the amount of amplicon loaded, a reduction in the number of SSCP bands was observed with IFN-alpha therapy (median number of SSCP bands per patient was eight before therapy and two after therapy). In the seven patients within each of the ribavirin- and placebo-treated groups, there was no significant difference in the viraemia level, number of SSCP bands per patient or the SSCP band pattern, before and after therapy. These findings suggest that at the doses given, IFN-alpha, but not ribavirin, exerts a selective pressure on HCV quasispecies heterogeneity.

Effect of interferon-alpha and ribavirin therapy on serum GB virus C/hepatitis G virus (GBV-C/HGV) RNA levels in patients chronically infected with hepatitis C virus and GBV-C/HGV

GB virus C/hepatitis G virus (GBV-C/HGV) is a newly described virus associated with hepatitis in humans, and GBV-C/HGV coinfection is common in patients chronically infected with hepatitis C virus (HCV). To determine the clinical impact of GBV-C/HGV infection in such patients and the effect of interferon-alpha and ribavirin therapy on serum GBV-C/HGV RNA levels, GBV-C/HGV RNA was detected and quantitated in serum samples from 62 chronically infected HCV patients by a combination of a qualitative nested reverse transcription-polymerase chain reaction and a newly developed quantitative branched DNA assay: 10 patients were positive for serum GBV-C/HGV RNA. There were no differences in the clinical, biochemical, and histologic features of the patients with GBV-C/HGV-HCV coinfection compared with those with HCV infection alone. Interferon-alpha treatment caused a marked but usually transient reduction in serum GBV-C/HGV RNA, and ribavirin had, at most, a modest antiviral effect.

Resistance and integron characterization of Acinetobacter baumannii in a teaching hospital in Chongqing, China

A total of 189 Acinetobacter baumannii isolates were collected in 2011 from a teaching hospital in Chongqing, China. Susceptibility data showed strains carrying integrons were significantly more resistant to all tested antibiotics that strains lacking integrons. Five types of gene cassettes belonging to class I integrons were identified in this study, and for the first time two types of gene cassettes belonging to class II integrons are reported. Most of the cassettes belong to a class I integron (136/144) encoding arr3, aacA4, dfrA17, aadA5, aadB, cat, blaOXA10 , aadA1, aadA2, dfrA and aacC1. Isolates contained a class I gene cassette; AadA2-HP-dfrA was the prevalent strain in this hospital. A class II integron was detected in eight strains, which contained the type IV fimbriae expression regulatory gene pilR and sulfate adenylyltransferase, suggesting a possible role in multidrug resistance. The major epidemic strains from intensive care unit patients belong to international clone 2. In conclusion, the presence of integrons was significantly associated with multiple drug resistance of A. baumannii in this hospital, and class I integron isolates bearing AadA2-HP-dfrA were the prevalent strain in this hospital.

Testosterone regulates mitochondrial aspartate aminotransferase gene expression and mRNA stability in prostate

The effect of testosterone on the precursor mitochondrial aspartate aminotransferase (pmAAT) gene and on pmAAT-mRNA was studied in rat ventral prostate (VP) and pig prostate epithelial cells. Castration significantly decreased the level of nuclear pmAAT transcripts in VP; whereas testosterone treatment of castrated animals restored the level of pmAAT transcripts. Correspondingly, castration resulted in a marked decrease in the transcription rate of the pmAAT gene; whereas testosterone treatment markedly increased the transcription rate. In vitro studies with isolated pig prostate epithelial cells demonstrated that testosterone directly and rapidly induced a transient increase in the transcription rate of the pmAAT gene. The increase in transcription was associated with an increase in the steady-state level of pmAAT-mRNA. Similar in vitro effects were observed with isolated VP epithelial cells. In addition to its stimulatory effect on transcription of the pmAAT gene, testosterone also increased the half-life of pmAAT-mRNA from 2 h in the absence of hormone to 16 h in its presence. Consequently, testosterone appears to stabilize the pmAAT-mRNA. The combination of its immediate effect on stimulating the transcription of the pmAAT gene and its stabilizing effect on pmAAT-mRNA would account for the increase in the steady-state level of pmAAT-mRNA by testosterone. These studies support our proposal that, through these effects, testosterone increases the biosynthesis of mAAT thereby increasing the transamination of aspartate to oxaloacetate and ultimately increasing the synthesis of citrate. This appears to provide at least one of the mechanisms by which testosterone regulates prostate citrate production.

alpha-Glutathione S-transferase as a marker of hepatocellular damage in chronic hepatitis C virus infection

alpha-Glutathione S-transferase (alpha GST) may be a good serologic marker of hepatocellular damage because of its low molecular weight, uniform hepatic distribution, high cytosolic concentration, and short half-life. To determine the clinical utility of alpha GST in patients with chronic hepatitis C virus (HCV) infection, serum alpha GST levels were measured in 96 patients with chronic HCV infection, of whom 47 subsequently underwent interferon-alpha therapy. Patients were simultaneously evaluated with conventional liver biochemistry, serum HCV RNA levels, and liver histology. Different methods of serum collection did not affect alpha GST values, indicating that this was a stable serum marker. In 93% of patients with chronic HCV infection, alpha GST was elevated and showed an excellent correlation with serum aminotransferases. Histologic analysis revealed a correlation of alpha GST with both lobular inflammation and bile duct lesions. There was no correlation between serum alpha GST levels and the demographic features, mode of transmission, virologic, other histologic parameters, or subsequent response to interferon-alpha. During serial monitoring in patients undergoing interferon-alpha therapy, elevation of serum alpha GST correlated with biochemical relapse and in some patients virologic relapse in the presence of normal liver biochemistry. alpha GST was persistently elevated in all nonresponders. Four of six of those patients who responded completely followed by early relapse had elevated alpha GST intermittently or continuously during therapy despite normalization of serum aminotransferases. Two of five of those with a complete and sustained response had elevated alpha GST during treatment and follow-up, and both were also seropositive for HCV RNA during follow-up. These data demonstrate that alpha GST is a stable marker, has similar diagnostic utility as serum aminotransferases, and may have a role in the monitoring of patients undergoing interferon-alpha therapy.

High prevalence of GB virus-C/hepatitis G virus infection in liver transplant recipients

BACKGROUND

To determine the prevalence of GB virus-C/hepatitis G virus (GBV-C/HGV) infection in liver transplant recipients transplanted for non-hepatitis C virus indications, 44 patients transplanted for cryptogenic, autoimmune, hepatitis B, or cholestatic liver disease and 91 non-liver transplantation (LT) patients with similar diagnoses seen in the same study period (control group) were studied.

METHODS

HGV RNA was detected by reverse transcription polymerase chain reaction with primers from the 5'-untranslated region.

RESULTS

GBV-C/HGV RNA was commonly detected in post-LT patients compared with the control group (28/44 [64%] vs. 13/91 [14%]; P<0.001). GBV-C/HGV infection was not related to the number of blood products transfused, a particular surgeon, or a specific liver disease. GBV-C/HGV infection also had no significant impact on the post-LT clinical profile.

CONCLUSIONS

We conclude that GBV-C/HGV infection is very common in LT recipients, but that it has minimal clinical impact in this population.

Detection of GB virus-C/hepatitis G virus RNA in serum by reverse transcription polymerase chain reaction

Three PCR methods based on the GB virus-C/hepatitis G virus (GBV-C/HGV) 5'UTR and NS3 genomic region were used for the detection of GBV-C/HGV RNA in serum of 62 patients with chronic hepatitis C virus (HCV) infection. Ten of 62 (16%) patients were found to have GBV-C/HGV RNA, which was confirmed by sequence analysis of the 5'UTR PCR amplicon. All methods appear to be specific, but methods based on the 5'UTR appear to be more sensitive.

Quantification of serum HCV core antigen by a fluorescent enzyme immunoassay in liver transplant recipients with recurrent hepatitis C--clinical and virologic implications

BACKGROUND

Monitoring hepatitis C viremia may be useful in the management of liver transplant patients with recurrent hepatitis C virus (HCV) infection. The clinical utility of a newly described fluorescent enzyme immunoassay for the detection of serum HCV core antigen was evaluated.

METHODS

Serum samples prospectively collected from 57/63 consecutive patients transplanted for HCV-related end-stage liver disease were assayed for both serum HCV core antigen by fluorescent enzyme immunoassay and HCV RNA level using a branched chain DNA signal amplification assay. HCV genotype was determined by restriction fragment length polymorphism analysis based on 5' untranslated region. One- and 2-year annual protocol liver biopsies from these patients were graded for inflammation, fibrosis, and cholestasis

RESULTS

Serum HCV core antigen and HCV RNA were detected in a similar proportion of samples (256/ 281 vs. 260/281, P=NS), and there was an excellent correlation between assays (r2=0.905, P<0.0001) independent of HCV genotype. A conversion equation between HCV core antigen and HCV RNA was constructed to estimate the HCV core antigen to RNA ratio to be around 231 to 1. Mean serum HCV core antigen levels peaked initially at 3 months posttransplant but there was significant interpatient variation as to when peak levels occurred. A high serum HCV core antigen level in the first 6 months was associated with histological deterioration in terms of bridging fibrosis, cirrhosis, severe cholestasis, or retransplantation by 2-year follow-up.

CONCLUSION

Determination of serum HCV core antigen level reflects HCV viremia and may have clinical implications in liver transplant patients with HCV recurrence.