Measurement of serum hyaluronic acid in patients with chronic hepatitis C and its relationship to liver histology. Consensus Interferon Study Group

BACKGROUND AND AIMS

Chronic hepatitis C is a slowly progressing inflammatory disease of the liver that can lead to cirrhosis and its complications. Assessment of liver damage in hepatitis C has been primarily via histological evaluation. Liver biopsy, while useful in determining the extent of liver damage, has associated costs and places patients at a small but finite risk of bleeding. Studies in small patient populations have identified serum markers shown to correlate with liver histology, including procollogen III peptide and hyaluronic acid (HA). To determine whether serum HA was a reliable predictor of cirrhosis and fibrosis, we examined serum HA concentrations from 486 chronic Hepatitis C virus (HCV) patients.

METHODS AND RESULTS

Patients were anti-HCV and HCV RNA positive, with elevated alanine aminotransferase values and underwent a liver biopsy. Sera were obtained at the baseline for HA using radioimmunoassay methodology. Patients with cirrhosis had significantly higher serum HA concentrations compared with non-cirrhotic patients (382+/-31 vs 110+/-9 microg/L respectively, P< 0.001). Patients with fibrosis had significantly higher mean serum HA concentrations (179+/-11 microg/L) compared with patients without fibrosis (62+/-20 microg/L; P< 0.001). The correlation between HA concentration and the components of the Knodell histological activity index score revealed no strong associations with the exception of fibrosis, which showed moderate correlation (R=0.5421, P<0.001). The clinical value of HA measurement appears to be its ability to exclude cirrhosis. A HA value of < 60 microg/L excluded the presence of cirrhosis or significant fibrosis with a predictive value of 99 and 93%, respectively.

CONCLUSIONS

Serum HA measurement may be clinically useful to non-invasively assess the degree of fibrosis and cirrhosis. Further prospective studies are warranted to determine the clinical utility of HA as a non-invasive marker of liver fibrosis.

Hippocampal pyramidal cell orientation in schizophrenia. A controlled neurohistologic study of the Yakovlev collection

The finding of marked disorganization of the hippocampal pyramidal cell layer in the brains of schizophrenic patients has recently been reported. The present study was undertaken to determine whether similar abnormalities could be found in the brains of a population of schizophrenic patients, most of whom were never exposed to neuroleptics. Though statistical analysis of 2808 pyramidal cells failed to reveal significantly greater disorganization in a group of seven alleged schizophrenic brains than in brains of age-matched, nonpsychotic controls, the data suggest a relationship between the degree of pyramidal cell disarray and the severity of behavioral impairment due to psychosis. The implications and pitfalls in interpreting these findings are discussed.

Twenty years of the German Environmental Survey (GerES): Human biomonitoring – Temporal and spatial (West Germany/East Germany) differences in population exposure

The German Environmental Surveys (GerESs) are nationwide population studies, which have repeatedly been carried out in Germany since the mid-1980s. The subjects were representatively selected from the regional registration offices with regard to age, gender and community size. The first survey for adults (GerES I) was carried out in 1985/1986 (West Germany) followed by GerES IIa in 1990/1991 (West Germany) and GerES IIb in 1991/1992 (East Germany). In GerES II children were also included to some extent. In 1998, the third GerES for adults was conducted in both parts of Germany (GerES III). The current survey 2003/2006 (GerES IV) is focussing exclusively on children. A 1-year pilot study was conducted in 2001-2002 to collect information on parameters influencing the response rate and to test the suitability of the different instruments intended to be used for the main study. The main goal of the surveys is to analyse and document the extent, distribution and determinants of exposure to environmental pollutants of the German general population. Three main instruments of investigation were comprised in GerES: human biomonitoring (HBM), monitoring of the domestic environment, and collecting information on exposure pathways and living conditions via questionnaires. This paper is focussed on the general design of the GerESs, the trend over time and spatial differences (West Germany and East Germany) for HBM data on arsenic, cadmium, lead, mercury, pentachlorophenol (PCP), and polycyclic aromatic hydrocarbons (PAH). These substances have been determined in blood and/or morning urine of adults and children. All GerESs have been conducted in close connection with the National Health Interview and Examination Surveys performed by the Robert Koch-Institute, Berlin.

Assessment of hepatitis C virus RNA and genotype from 6807 patients with chronic hepatitis C in the United States

Hepatitis C virus (HCV) RNA status and HCV genotype have become important tools in the diagnosis and monitoring of therapy in chronic HCV infection. To establish a database with respect to HCV genotype and serum HCV RNA concentrations in chronic hepatitis C patients in the United States, we analysed 6807 chronic hepatitis C patients who had HCV RNA and HCV genotype tests conducted at a central laboratory. The HCV RNA concentration cut-off for the lower 25th percentile of this population (low titre) was 0.9 x 106 copies ml-1. The median HCV RNA concentration was 3.5 x 106 copies ml-1 and the cut-off for the upper 25th percentile (high titre) was 5 x 106 copies ml-1. Male patients had a median HCV RNA concentration of 3.9 x 106 copies ml-1, which was significantly higher than the median HCV RNA level for females (2.75 x 106 copies ml-1; P < 0.001). HCV genotype 1 was detected in 73% of patients; genotype 2 in 14%; genotype 3 in 8%; mixed genotype in 4%; and genotypes 4, 5 and 6 with a frequency of < 1%. Patients from the Northeast, Southeast and Midwest had significantly (P < 0.001) more infections with genotype 1 than patients from the Western and Southern regions. African-American patients were more likely to be infected with genotype 1 when compared with Caucasian, Hispanic or Asian Pacific Islanders (P < 0.001). Patients infected with HCV genotype 1 and mixed HCV genotypes had significantly higher serum HCV RNA concentrations when compared with HCV genotypes 2 and 3 (P < 0.001 for all comparisons).

Sequence and analysis of chromosome 3 of the plant Arabidopsis thaliana

Arabidopsis thaliana is an important model system for plant biologists. In 1996 an international collaboration (the Arabidopsis Genome Initiative) was formed to sequence the whole genome of Arabidopsis and in 1999 the sequence of the first two chromosomes was reported. The sequence of the last three chromosomes and an analysis of the whole genome are reported in this issue. Here we present the sequence of chromosome 3, organized into four sequence segments (contigs). The two largest (13.5 and 9.2 Mb) correspond to the top (long) and the bottom (short) arms of chromosome 3, and the two small contigs are located in the genetically defined centromere. This chromosome encodes 5,220 of the roughly 25,500 predicted protein-coding genes in the genome. About 20% of the predicted proteins have significant homology to proteins in eukaryotic genomes for which the complete sequence is available, pointing to important conserved cellular functions among eukaryotes.

MRI-based measurements of temporal lobe and ventricular structures in patients with bipolar I and bipolar II disorders

OBJECTIVE

There have been relatively few quantitative MRI studies of temporal lobe structures and the lateral ventricles in bipolar patients and a lack of agreement across studies as to whether these structures differ significantly in size from control subjects. Also there have been no quantitative MRI studies of bipolar II patients. The present study measured temporal lobe and ventricular structures in both bipolar I and bipolar II patients, as well as control subjects.

METHOD

Twenty-five bipolar I patients, 22 bipolar II patients and 19 control subjects underwent MRI brain scans. The 5 mm coronal slices of each subject were coded and measured by a rater who was blind with respect to subject diagnosis. Volume estimates of the temporal lobe and hippocampus were calculated for each hemisphere by measuring the area of the structure in each slice in which it appears, multiplying by 5 mm and summing. In addition to these volume estimates, the area of the lateral ventricle and the inferior horn of the lateral ventricle, the lateral ventricle to cerebrum area ratio (LV/C) and the temporal lobe to cerebrum area ratio (TL/C), were calculated for each hemisphere in one reference slice only. The area of the third ventricle was also measured. Volume estimates and area ratios were then compared among diagnostic groups.

RESULTS

There were no significant differences in temporal lobe or hippocampal volume estimates, in the third ventricle and inferior horn of the lateral ventricle area measurements, and in the TL/C area ratio among diagnostic groups. The lateral ventricle area and LV/C area ratio were significantly larger in bipolar I patients than either bipolar II patients or control subjects only in the left hemisphere. Furthermore, these measures were approximately twice as large in the bipolar I patients as the other groups.

CONCLUSIONS

The current study adds to a growing literature that bipolar I disorder, particularly in males, may show different neurobiological alterations compared to bipolar II patients or control subjects. The pathophysiologic implications of this accumulating evidence of increased left ventricular size in bipolar I disorder remains to be further elucidated.

Patients co-infected with human immunodeficiency virus and hepatitis C virus demonstrate higher levels of hepatic HCV RNA

Serum and liver hepatitis C virus (HCV) RNA levels in patients with hepatitis C have previously been quantified using different techniques. In this work, we used an automated, multicycle, polymerase chain reaction (PCR)-based technique to quantify HCV RNA in 1-2 mm of frozen liver tissue, and in serum, from 70 patients with antibodies to HCV (anti-HCV), with and without human immunodeficiency virus (HIV) co-infection. Stored liver tissue and sera collected at the time of liver biopsy were used for measurement of HCV RNA. Forty-eight HCV patients and 22 HIV/HCV co-infected patients were studied. Co-infected patients had significantly higher median serum and liver HCV RNA (6.7 log copies ml-1 serum and 2.90 log copies microg-1 liver nucleic acids) than patients with HCV alone (6.2 log copies ml-1 serum and 2.19 log copies microg-1 liver nucleic acids). There was only a weak correlation between serum and liver HCV RNA (r = 0.43). There was no correlation between liver and serum HCV RNA and host factors such as duration of disease, CD4 counts, alanine aminotransferase levels or histological score. There was no correlation with HCV genotype. Co-infected patients were more likely to harbour HCV genotype 1 (85%) when compared to patients with HCV alone (58%). An identical genotype was found in liver and serum in 89% of those tested; in 11%, a mixed genotype was present in serum. Patients with HCV genotypes 1 and non-1 had similar histological scores. Hence, an automated PCR-based technique is useful for measuring both liver and serum HCV RNA. Serum HCV genotypes closely paralleled those found in liver tissue. HIV co-infection was associated with higher serum, as well as intrahepatic, HCV RNA levels, by mechanisms not directly related to CD4 counts. The lack of correlation between liver HCV RNA and histology suggests that HCV is not directly cytopathic.

Inhibition of hepatitis C virus (HCV)-RNA-dependent translation and replication of a chimeric HCV poliovirus using synthetic stabilized ribozymes

Ribozymes are catalytic RNA molecules that can be designed to cleave specific RNA sequences. To investigate the potential use of synthetic stabilized ribozymes for the treatment of chronic hepatitis C virus (HCV) infection, we designed and synthesized hammerhead ribozymes targeting 15 conserved sites in the 5' untranslated region (UTR) of HCV RNA. This region forms an internal ribosome entry site that allows for efficient translation of the HCV polyprotein. The 15 synthetic ribozymes contained modified nucleotides and linkages that stabilize the molecules against nuclease degradation. All 15 ribozymes were tested for their ability to reduce expression in an HCV 5' UTR/luciferase reporter system and for their ability to inhibit replication of an HCV-poliovirus (HCV-PV) chimera. Treatment with several ribozymes resulted in significant down-regulation of HCV 5' UTR/luciferase reporter expression (range 40% to 80% inhibition, P <.05). Moreover, several ribozymes showed significant inhibition (>90%, P <.001) of chimeric HCV-PV replication. We further show that the inhibitory activity of ribozymes targeting site 195 of HCV RNA exhibits a sequence-specific dose response, requires an active catalytic ribozyme core, and is dependent on the presence of the HCV 5' UTR. Treatment with synthetic stabilized anti-HCV ribozymes has the potential to aid patients who are infected with HCV by reducing the viral burden through specific targeting and cleavage of the viral genome.

Microbiologic epidemiology depending on time to occurrence of prosthetic joint infection: a prospective cohort study

OBJECTIVES

The high microbiologic diversity encountered in prosthetic joint infection (PJI) makes the choice of empirical antimicrobial therapies challenging, especially in cases of implant retention or one-stage exchange. Despite the risk of dysbiosis and toxicity, the combination of vancomycin with a broad-spectrum β-lactam is currently recommended in all cases, even if Gram-negative bacilli (GNB) might be less represented in late PJI. In this context, this study aimed to describe the microbiologic epidemiology of PJI according to the chronology of infection.

METHODS

This prospective cohort study (2011-2016) evaluated the microbiologic aetiology of 567 PJI according to time of occurrence from prosthesis implantation-early (<3 months), delayed (3-12 months) and late (>12 months)-as well as mechanism of acquisition.

RESULTS

Initial microbiologic documentation (n = 511; 90.1%) disclosed 164 (28.9%) Staphylococcus aureus (including 26 (16.1%) methicillin-resistant S. aureus), 162 (28.6%) coagulase-negative staphylococci (including 81 (59.1%) methicillin-resistant coagulase-negative staphylococci), 80 (14.1%) Enterobacteriaceae, 74 (13.1%) streptococci and 60 (10.6%) Cutibacterium acnes. Considering nonhaematogenous late PJI (n = 182), Enterobacteriaceae (n = 7; 3.8%) were less represented than in the first year after implantation (n = 56; 17.2%; p <0.001), without difference regarding nonfermenting GNB (4.6% and 2.7%, respectively). The prevalence of anaerobes (n = 40; 21.9%; including 32 (80.0%) C. acnes) was higher in late PJI (p <0.001). Consequently, a broad-spectrum β-lactam might be useful in 12 patients (6.6%) with late PJI only compared to 66 patients (20.3%) with early/delayed PJI (p <0.001).

CONCLUSIONS

Considering the minority amount of GNB in late postoperative PJI, the empirical use of a broad-spectrum β-lactam should be reconsidered, especially when a two-stage exchange is planned.

Prediction of response during interferon alfa 2b therapy in chronic hepatitis C patients using viral and biochemical characteristics: a comparison

Patients with chronic hepatitis C (n = 103) were treated for 24 weeks with interferon alfa 2b and followed up for 24 weeks after cessation of therapy (week 48). When hepatitis C virus (HCV) RNA at week 48 was used to assess interferon response, 15 (14.6%) were virological complete responders, and all have remained HCV RNA negative for a mean of 3 years. At week 48, 3 of 15 virological complete responders had elevated alanine transaminase (ALT) values. When serum ALT level was used at week 48 to determine response to interferon, 20 (19.4%) were biochemical complete responders. However, 8 of the 20 patients with normal ALT levels were HCV RNA positive at week 48, and 7 of these individuals have had a recurrence of elevated ALT levels within 3 years after cessation of treatment. These findings indicate that measurement of HCV RNA was more accurate than ALT in determining true responses to interferon therapy. Identification of nonresponders early during the course of interferon treatment showed that an elevated ALT level at week 12 was 92% predictive (odds ratio 3.7) but misidentified 33% (5 of 15) of the patients who were virological complete responders at week 48. In contrast, a positive HCV RNA at week 12 of treatment was 98% predictive (odds ratio 35.5) and misidentified only 6.7% (1 of 15) of the virological complete responders. Thus, positive HCV RNA at week 12 of therapy was more accurate in identifying eventual virological nonresponders than measurement of ALT at this time. Termination of interferon therapy in patients who were HCV RNA positive at week 12 would result in a 27% reduction in the direct medical costs and keep patients from undergoing unnecessary treatment. Therefore, testing for HCV RNA at week 12 to identify nonresponders and then discontinuing their treatment is practical, cost-efficient and beneficial both to patients and to third-party payers.

Clinical significance of concomitant hepatitis C infection in patients with alcoholic liver disease

The significance of antibodies to hepatitis C virus in patients with chronic alcoholic liver disease is unclear. Prior studies have utilized the first-generation enzyme-linked immunosorbent assay, which is limited by problems with sensitivity and specificity. Hepatitis C virus infection in 137 patients with biopsy-proven alcoholic liver disease was assessed with second-generation hepatitis C virus antibody assays and reverse transcription-polymerase chain reaction for detection of hepatitis C virus RNA in the serum. The patients were categorized into three groups according to results of serological testing. Discriminant-function analysis was used to determine which factors (risk, biochemical and histological) could best differentiate the three groups. Thirty-three patients were reactive on second-generation enzyme-linked immunosorbent assay/second-generation recombinant immunoblot assay and RNA positive (group 1). Twelve were reactive on second-generation enzyme-linked immunosorbent assay/second-generation recombinant immunoblot assay but RNA negative (group 2). Eighty-six were nonreactive on second-generation enzyme-linked immunosorbent assay, and six were reactive on second-generation enzyme-linked immunosorbent assay but negative on second-generation recombinant immunoblot assay and negative for hepatitis C virus RNA (group 3). Seventy-six percent of patients in group 1 and 58% in group 2 had parenteral risk factors, compared with only 1% in group 3 (p < 0.00001). The mean ALT level was higher in group 1 patients (p < 0.05). The mean histologic activity index was significantly higher in group 1 (p = 0.0007).(ABSTRACT TRUNCATED AT 250 WORDS)

Cloning and characterization of a new member of the Nudix hydrolases from human and mouse

Proteins containing the Nudix box "GX(5)EX(7)REUXEEXGU" (where U is usually Leu, Val, or Ile) are Nudix hydrolases, which catalyze the hydrolysis of a variety of nucleoside diphosphate derivatives. Here we report cloning and characterization of a human cDNA encoding a novel nudix hydrolase NUDT5 for the hydrolysis of ADP-sugars. The deduced amino acid sequence of NUDT5 contains 219 amino acids, including a conserved Nudix box sequence. The recombinant NUDT5 was expressed in Escherichia coli and purified to near homogeneity. At the optimal pH of 7, the purified recombinant NUDT5 catalyzed hydrolysis of two major substrates ADP-ribose and ADP-mannose with K(m) values of 32 and 83 microM, respectively; the V(max) for ADP-mannose was about 1.5 times that with ADP-ribose. The murine NUDT5 homolog was also cloned and characterized. mNudT5 has 81% amino acid identity to NUDT5 with catalytic activities similar to NUDT5 under the optimal pH of 9. Both NUDT5 and mNudT5 transcripts were ubiquitously expressed in tissues analyzed with preferential abundance in liver. The genomic structures of both NUDT5 and mNudT5 were determined and located on human chromosome 10 and mouse chromosome 2, respectively. The role of NUDT5 in maintaining levels of free ADP-ribose in cells is discussed.

Correlation of serum HCV RNA and alanine aminotransferase levels in chronic hepatitis C patients during treatment with ribavirin

To evaluate the effect of ribavirin on serum hepatitis C virus (HCV) RNA and alanine aminotransferase (ALT) levels, 22 patients with chronic HCV infection were treated with oral ribavirin 1200 mg daily in three divided doses for 4 weeks. At the end of 4 weeks treatment, the serum ALT decreased in all but one patient and became normal in three individuals. The mean pretreatment serum ALT was reduced significantly from 193 +/- 45 i.u./L to 95 +/- 16 i.u./L after 4 weeks therapy (P = 0.009). However, 8 weeks after cessation of treatment, the serum ALT rose to a mean value of 154 +/- 21 i.u./L. The mean pretreatment serum HCV RNA was not significantly decreased at the end of 4 weeks treatment (7.0 x 10(5) vs. 4.1 x 10(5) copies/mL, P > 0.05). However, serum HCV RNA levels were decreased in 12 and increased in 10 patients at the end of 4 weeks therapy. Eight weeks after cessation of therapy, the serum HCV RNA of 22 patients rose to a mean value of 4.9 +/- 10(5) copies/mL. Six patients who continued to have elevated serum ALT and positive HCV RNA after the initial 4 weeks treatment received oral ribavirin at the same dosage for an additional 24 weeks. The serum ALT again decreased in all six patients during therapy, but rose to pretreatment values by 8 weeks after cessation of the treatment. In addition, no significant changes were noted in the mean serum HCV RNA levels during and after 24 weeks of ribavirin therapy.(ABSTRACT TRUNCATED AT 250 WORDS)

Prevention by specific perceptual remediation for vulnerable first-graders. Controlled study and follow-up of lasting effects

In a pretest-posttest design with two matched control groups, 86 first-graders screened as vulnerable to academic failure and behavioral decompensation were each assigned to one of three groups: (1) channel-specific perceptual stimulation, (2) regular academic tutoring (contact controls), or (3) no contact. On most measures, including perceptual and achievement tests and behavior ratings by teachers, group 1 showed more improvement than either of the control groups. Several of these differences were significant (P less than .05, two-tailed). In general, the two control groups came closer to each other than to group 1. With no further intervention, follow-up one year later showed more dramatic significance. On every measure, group 1's improvement surpassed that of the control groups, and diverged from them even more than at posttest; this divergence was significant on most measures. Group 1 improved significantly (P less than .05 to P less than .01) in reading, IQ, and three behavior scales, while both control groups showed only deterioration on these measures. Group 1 gained five IQ points on the Wechsler Intelligence Scale for Children, while the controls lost five. On the Davids Scale, group 1 improved significantly (P less than .01) to "probably not hyperkinetic," while both control groups deteriorated to "probably hyperkinetic." The hypothesized mechanism of group 1's behavioral superiority at follow-up was its significant (P less than 0.1) reading improvement, with secondary emotional benefits.

Genes involved in the determination of the rate of inversions at short inverted repeats

BACKGROUND

Not all of the enzymatic pathways involved in genetic rearrangements have been elucidated. While some rearrangements occur by recombination at areas of high homology, others are mediated by short, often interrupted homologies. We have previously constructed an Escherichia coli strain that allows us to examine inversions at microhomologies, and have shown that inversions can occur at short inverted repeats in a recB,C-dependent fashion.

RESULTS

Here, we report on the use of this strain to define genetic loci involved in limiting rearrangements on an F' plasmid carrying the lac genes. Employing mini-Tn10 derivatives to generate insertions near or into genes of interest, we detected three loci (rmuA,B,C) that, when mutated, increase inversions. We have mapped, cloned and sequenced these mutator loci. In one case, inactivation of the sbcC gene leads to an increase in rearrangements, and in another, insertions near the recE gene lead to an even larger increase. The third gene involved in limiting inversions, rmuC, has been mapped at 86 min on the E. coli chromosome and encodes a protein of unknown function with a limited homology to myosins, and some of the SMC (structural maintenance of chromosomes) proteins.

CONCLUSIONS

This work presents the first example of an anti-mutator role of the sbcC,D genes, and defines a new gene (rmuC) involved in DNA recombination.

German Environmental Survey (GerES): Human biomonitoring as a tool to identify exposure pathways

The German Environmental Survey (GerES) is a representative population study and has been repeatedly carried out since the mid-1980s. The currently run survey (GerES IV) is the first one solely targeted on children. The GerES IV Pilot Study resulted in first insights into major exposure pathways relevant to children. These insights were made possible by the determination of pollutant concentrations in blood and urine and the additional consideration of their occurrence in the indoor environment and by using questionnaire data. The results of the GerES IV Pilot Study are presented according to major exposure pathways such as house dust, food and environmental tobacco smoke (ETS). An overview on relevant pilot study results is given. The results of GerES IV will permit the verification and substantiation of the pilot study results.

Detection of de novo hepatitis C virus infection by polymerase chain reaction in hemodialysis patients

Patients on chronic hemodialysis (HD) treatment have been identified by serological testing, including second- and third-generation enzyme-linked immunosorbent assay (ELISA), as a high-risk group for hepatitis C virus (HCV) infection. Previous studies have shown that de novo cases of HCV may occur in HD units in the absence of other parenteral exposures, which suggests the spread of HCV between patients. In addition, the reverse-transcription polymerase chain reaction (RT-PCR), which directly detects HCV virus, has identified HCV infection in chronic HD patients who are seronegative. The aim of this study was to determine the incidence of HCV infection detected by RT-PCR technology in a large cohort of chronic HD patients. One hundred and twenty chronic HD patients, HCV-negative by serological assays (second-generation ELISA) and molecular techniques (branched DNA and RT-PCR), were observed for a mean period of 9.5 months. They were tested monthly for serum alanine aminotransferase levels (ALT) and by second-generation ELISA. At the end of the follow-up period, they were again evaluated by branched DNA and RT-PCR testing. HCV RNA was detected in patients' sera by RT followed by PCR using two separate primer sets from the 5'-untranslated region of the HCV genome. Southern blot was performed using a digoxigenin-labeled probe. Two patients who had HCV RNA detectable by RT-PCR at the end of the follow-up period remained branched-DNA-negative. Thus, the incidence of de novo acquisition of HCV infection in the current investigation was 2.1% per year. In 1 patient RT-PCR positivity and anti-HCV ELISA seroconversion occurred. The 2nd patient remained anti-HCV ELISA-negative, although viremic. In both patients, the onset of positivity by RT-PCR was associated with a rise of ALT levels into the 'abnormal range' in our laboratory. In these 2 patients, de novo acquisition of HCV infection was observed in the absence of obvious parenteral risk factors other than their presence in the HD environment. In conclusion, de novo acquisition of HCV infection may be undetected by ELISA and branched-DNA assays. The need to monitor chronic HD patients by serial ALT testing is emphasized. RT-PCR should be incorporated into diagnostic testing for HCV infection in chronic HD patients. RT-PCR technology can identify HCV in HD individuals with raised ALT activity.

Broad spectrum antibacterial activity of a mixture of isothiocyanates from nasturtium (Tropaeoli majoris herba) and horseradish (Armoraciae rusticanae radix)

Isothiocyanates have been reported to exert antimicrobial activity. These compounds are found in a licensed native preparation of nasturtium (Tropaeoli majoris herba) and horseradish (Armoraciae rusticanae radix) which is used for treatment of upper respiratory and urinary tract infections. The aim of our investigation was to assess the antimicrobial activity of a mixture of the contained benzyl-, allyl-, and phenylethyl- isothiocyanates against clinically important bacterial and fungal pathogens including antimicrobial resistant isolates. Susceptibility testing was performed by agar-dilution technique. Isothiocyanates were mixed in proportions identical to the licensed drug. Minimum inhibitory- and minimum bactericidal concentrations were assessed. The Minimum inhibitory concentration90 was defined as the concentration which inhibited 90% of the microbial species tested. H. influenzae, M. catarrhalis, S. marcescens, P. vulgaris, and Candida spp. were found to be highly susceptible, with minimum inhibitory concentration90 -values ranging between ≤0.0005% and 0.004% (v/v) of total ITC. Intermediate susceptibilities were observed for S. aureus, S. pyogenes, S. pneumoniae, K. pneumoniae, E. coli and P. aeruginosa, with Minimum inhibitory concentration90 -values ranging between 0.004% and 0.125% (v/v), but with elevated Minimum bactericidal concentrations90-values (2-7 dilution steps above Minimum inhibitory concentration90). Low susceptibilities were determined for viridans streptococci and enterococci. Interestingly, both resistant and non-resistant bacteria were similarly susceptible to the test preparation.

Is there an optimal time to measure quantitative HCV RNA to predict non-response following interferon treatment for chronic HCV infection?

BACKGROUND/AIMS

Current criteria to predict sustained response for a patient with chronic hepatitis C virus during interferon treatment are not consistent. The aim of this study was to determine a reliable point in time to predict non-response to therapy, as a theoretical basis for early cessation of treatment.

METHODS

Sera (-70 degrees C) from 66 patients treated with interferon (3 million units three times a week for 6 months) were assayed with a quantitative polymerase chain reaction (sensitivity < or =100 copies per milliliter). Evaluations were made at baseline, during treatment at weeks 1, 2, 4, 12, and 24, and at follow-up week 48. Biochemical response was defined using standard alanine aminotransferase criteria. Virologic response was defined as: sustained if loss of HCV RNA persisted through therapy and follow-up; relapse if HCV RNA became undetectable but reappeared during treatment or follow-up; and non-response if HCV RNA remained detectable during the study period. Alanine aminotransferase and HCV RNA results were analyzed at defined time intervals to determine a predictive value for non-response and sustained response.

RESULTS

HCV RNA results are a more accurate predictor than alanine aminotransferase for both non-response and sustained response. Serum HCV RNA predicted non-response better than sustained response. The optimal time to predict non-response with serum HCV RNA was treatment week 12.

CONCLUSIONS

Treatment week 12 results indicate that HCV RNA was a more accurate predictor for non-response than serum alanine aminotransferase. This prediction would have theoretically permitted stopping treatment for 75% of the patients in this study at treatment week 12 allowing an overall cost savings of 28%.

Distinctive Gene Expression Patterns Define Endodormancy to Ecodormancy Transition in Apricot and Peach

Dormancy is a physiological state that plants enter for winter hardiness. Environmental-induced dormancy onset and release in temperate perennials coordinate growth cessation and resumption, but how the entire process, especially chilling-dependent dormancy release and flowering, is regulated remains largely unclear. We utilized the transcriptome profiles of floral buds from fall to spring in apricot (Prunus armeniaca) genotypes with contrasting bloom dates and peach (Prunus persica) genotypes with contrasting chilling requirements (CR) to explore the genetic regulation of bud dormancy. We identified distinct gene expression programming patterns in endodormancy and ecodormancy that reproducibly occur between different genotypes and species. During the transition from endo- to eco-dormancy, 1,367 and 2,102 genes changed in expression in apricot and peach, respectively. Over 600 differentially expressed genes were shared in peach and apricot, including three DORMANCY ASSOCIATED MADS-box (DAM) genes (DAM4, DAM5, and DAM6). Of the shared genes, 99 are located within peach CR quantitative trait loci, suggesting these genes as candidates for dormancy regulation. Co-expression and functional analyses revealed that distinctive metabolic processes distinguish dormancy stages, with genes expressed during endodormancy involved in chromatin remodeling and reproduction, while the genes induced at ecodormancy were mainly related to pollen development and cell wall biosynthesis. Gene expression analyses between two Prunus species highlighted the conserved transcriptional control of physiological activities in endodormancy and ecodormancy and revealed genes that may be involved in the transition between the two stages.

A predictive model for the development of hepatocellular carcinoma, liver failure, or liver transplantation for patients presenting to clinic with chronic hepatitis C

OBJECTIVE

Chronic infection with hepatitis C may lead to the development of cirrhosis, liver failure, and hepatocellular carcinoma. However, not all patients progress to these endpoints. Ideally, clinicians could improve their capability of stratifying the risk and the time frame within which their patients will progress to these endpoints. The purpose of the present study was to construct statistical models predicting disease progression for individual patients.

METHODS

Study endpoints were the development of hepatocellular carcinoma, liver transplantation, or death due to liver disease. The study cohort was 256 patients with hepatitis C acquired from either blood transfusion or use of intravenous drugs. During follow-up, 17 patients developed hepatocellular carcinoma, seven received liver transplantation, and 12 died from liver disease.

RESULTS

On multivariate analysis a history of decompensation (relative risk [RR] 4.321, 95% confidence interval [CI] 1.777-10.511) and the serum albumin (RR 0.253, 95% CI 0.136-0.474) were independently associated with the study endpoints. Patients without a history of decompensation and with a serum albumin > or = 4.1 mg/dl had a 3.2% chance of developing the study endpoints within 5 yr. Patients with a history of decompensation and a serum albumin < 4.1 mg/dl had a 40% chance of developing a study endpoint within 5 yr. Baseline genotype and quantitative RNA were not associated with development of the clinical endpoints, with the exception of patients coinfected with two or more genotypes.

CONCLUSION

Thus, the serum albumin and a history of decompensation are useful for predicting the development of hepatocellular carcinoma, liver transplantation, and death due to liver disease among patients with hepatitis C.

The role of the mitochondrial creatine kinase system for myocardial function during ischemia and reperfusion

The subcellular distribution of ATP, ADP, creatine phosphate and creatine was studied in normoxic control, isoprenaline-stimulated and potassium-arrested guinea-pig hearts as well as during ischemia and after reperfusion. The mitochondrial creatine phosphate/creatine ratio was closely correlated to the oxidative activity of the hearts. This was interpreted as an indication of a close coupling of mitochondrial creatine kinase to oxidative phosphorylation. To further investigate the functional coupling of mitochondrial creatine kinase to oxidative phosphorylation, rat or guinea-pig heart mitochondria were isolated and the mass action ratio of creatine kinase determined at active or inhibited oxidative phosphorylation or in the presence of high phosphate, conditions which are known to change the functional state of the mitochondrial enzyme. At active oxidative phosphorylation the mass action ratio was one-third of the equilibrium value whereas at inhibited oxidative phosphorylation (N2, oligomycin, carboxyatractyloside) or in the presence of high phosphate, the mass action ratio reached equilibrium values. These findings show that oxidative phosphorylation is essential for the regulation of the functional state of mitochondrial creatine kinase. The functional coupling of the mitochondrial creatine kinase and oxidative phosphorylation indicated from the correlation of mitochondrial creatine phosphate/creatine ratios with the oxidative activity of the heart in situ as well as from the deviation of the mass action ratio of the mitochondrial enzyme from creatine kinase equilibrium at active oxidative phosphorylation in isolated mitochondria is in accordance with the proposed operation of a creatine shuttle in heart tissue.

A pilot study of daily subcutaneous interleukin-10 in patients with chronic hepatitis C infection

The Th1/Th2 cytokine balance is important in persistence of infection and liver injury in chronic hepatitis C. The aim of this study was to administer the anti-inflammatory cytokine, recombinant human interleukin-10 (rHuIL-10), for 28 days in patients with chronic hepatitis C and to assess the safety and measure the effect on alanine aminotransferase (ALT, a marker of hepatic inflammation) levels and serum hepatitis C virus (HCV) RNA values. Three treatment-naive and 13 interferon (IFN) nonresponder patients (total 16 patients) with compensated chronic HCV infection were enrolled in this study. Patients were randomized to receive rHuIL-10 at a dose of 4 or 8 microg/kg/day as a single daily subcutaneous injection for 28 days. ALT values and serum HCV RNA were measured at days 0, 1, 3, 8, 15, 22, and 28 during therapy and at follow-up 2 and 4 weeks after cessation of the 4-week treatment period. ALT values normalized in 9 of 16 patients during therapy and remained normal until the end of treatment in 8 patients. The decreases in ALT values occurred in both the 4 microg and 8 microg dosage groups and were seen in both IFN naive and nonresponder patients. Mean ALT values fell significantly during the study period but usually returned to pretreatment levels by the end of the 4-week follow-up period (p < 0.05). HCV RNA concentrations did not vary significantly during or after therapy. (No patient had either an increase or a decrease in HCV RNA levels of > or =1.5 log during the study.) The drug was well tolerated, with no adverse symptoms noted. Platelet counts fell transiently to 73,000 and 63,000 in 2 patients. No other toxicity was observed, and no patients discontinued therapy. In chronic hepatitis C, short-term therapy with IL-10 was well tolerated and caused transient normalization of ALT values in 50% of patients, which returned to pretreatment levels on cessation of treatment. There were no significant changes observed in serum HCV RNA concentrations during the study. These immunomodulatory effects are similar to those observed with ribavirin monotherapy in chronic hepatitis C. Further study of rHuIL-10 alone or in combination with antiviral agents in chronic hepatitis C is warranted.

Machine Learning-Based Presymptomatic Detection of Rice Sheath Blight Using Spectral Profiles

Early detection of plant diseases, prior to symptom development, can allow for targeted and more proactive disease management. The objective of this study was to evaluate the use of near-infrared (NIR) spectroscopy combined with machine learning for early detection of rice sheath blight (ShB), caused by the fungus Rhizoctonia solani. We collected NIR spectra from leaves of ShB-susceptible rice (Oryza sativa L.) cultivar, Lemont, growing in a growth chamber one day following inoculation with R. solani, and prior to the development of any disease symptoms. Support vector machine (SVM) and random forest, two machine learning algorithms, were used to build and evaluate the accuracy of supervised classification-based disease predictive models. Sparse partial least squares discriminant analysis was used to confirm the results. The most accurate model comparing mock-inoculated and inoculated plants was SVM-based and had an overall testing accuracy of 86.1% (N = 72), while when control, mock-inoculated, and inoculated plants were compared the most accurate SVM model had an overall testing accuracy of 73.3% (N = 105). These results suggest that machine learning models could be developed into tools to diagnose infected but asymptomatic plants based on spectral profiles at the early stages of disease development. While testing and validation in field trials are still needed, this technique holds promise for application in the field for disease diagnosis and management.