Development of risky varices in alcoholic cirrhosis with a well-maintained nutritional status

AIM: To compare the nutritional status between alcoholic compensated cirrhotic patients and hepatitis C virus (HCV)-related cirrhotic patients with portal hypertension.

METHODS: A total of 21 patients with compensated cirrhosis (14 with HCV-related cirrhosis and seven with alcoholic cirrhosis) who had risky esophageal varices were investigated. In addition to physical variables, including the body mass index, triceps skinfold thickness, and arm-muscle circumference, the nutritional status was also assessed using the levels of pre-albumin (pre-ALB), retinol-binding protein (RBP) and non-protein respiratory quotient (NPRQ) measured with an indirect calorimeter.

RESULTS: A general assessment for the nutritional status with physical examinations did not show a significant difference between HCV-related cirrhosis and alcoholic cirrhosis. However, the levels of pre-ALB and RBP in alcoholic compensated cirrhotic patients were significantly higher than those in HCV-related compensated cirrhotic patients. In addition, the frequency of having a normal nutritional status (NPRQ ≥ 0.85 and ALB value > 3.5 g/dL) in alcoholic compensated cirrhotic patients was significantly higher than that in HCV-related compensated cirrhotic patients.

CONCLUSION: According to our small scale study, alcoholic compensated cirrhotic patients can develop severe portal hypertension even with a relatively well-maintained liver function and nutritional status compared with HCV-related cirrhosis.

Effects of short-term gentle treadmill walking on subchondral bone in a rat model of instability-induced osteoarthritis

OBJECTIVE

Subchondral bone cyst (SBC) growth, caused by osteoclast activity during early knee osteoarthritis (OA) pathogenesis, should be treated to prevent further progressions of OA. In the present study, we evaluated the effects of gentle treadmill walking on subchondral bone and cartilage changes in an experimental rat model of destabilized medial meniscus (DMM).

METHOD

Twelve-week-old Wistar rats underwent DMM surgery in their right knee and sham surgery in their left knee and were assigned to either the sedentary group or walking group (n = 42/group). Animals in the walking group were subjected to treadmill exercise 2 days after surgery, which included walking for 12 m/min, 30 min/day, 5 days/week for 1, 2, and 4 week(s). Subchondral bone and cartilage changes were evaluated by micro-CT analysis, histological analysis, and biomechanical analysis.

RESULTS

Treadmill walking had a tendency to suppress SBC growth, which was confirmed by micro-CT (P = 0.06) and positive staining for tartrate-resistant acid phosphatase (TRAP) activity for the osteoclast number per bone surface (P = 0.09) 4 weeks after surgery. These changes coincide with the prevention of cartilage degeneration as evaluated by the Osteoarthritis Research Society International (OARSI) score (P < 0.05) and biomechanically softening (P < 0.05). Furthermore, treadmill walking could suppressed increasing osteocyte deaths (P < 0.01), which was positively correlated with the OARSI score (r = 0.77; P < 0.01).

CONCLUSION

These results indicate biomechanical and biological links exist between cartilage and subchondral bone; preventive effects of treadmill walking on subchondral bone deterioration might be partly explained by the chondroprotective effects.

Changes in primary metabolism under light and dark conditions in response to overproduction of a response regulator RpaA in the unicellular cyanobacterium Synechocystis sp. PCC 6803

The study of the primary metabolism of cyanobacteria in response to light conditions is important for environmental biology because cyanobacteria are widely distributed among various ecological niches. Cyanobacteria uniquely possess circadian rhythms, with central oscillators consisting from three proteins, KaiA, KaiB, and KaiC. The two-component histidine kinase SasA/Hik8 and response regulator RpaA transduce the circadian signal from KaiABC to control gene expression. Here, we generated a strain overexpressing rpaA in a unicellular cyanobacterium Synechocystis sp. PCC 6803. The rpaA-overexpressing strain showed pleiotropic phenotypes, including slower growth, aberrant degradation of an RNA polymerase sigma factor SigE after the light-to-dark transition, and higher accumulation of sugar catabolic enzyme transcripts under dark conditions. Metabolome analysis revealed delayed glycogen degradation, decreased sugar phosphates and organic acids in the tricarboxylic acid cycle, and increased amino acids under dark conditions. The current results demonstrate that in this cyanobacterium, RpaA is a regulator of primary metabolism and involved in adaptation to changes in light conditions.

Genomewide association study identifies HAS2 as a novel susceptibility gene for adult asthma in a Japanese population

BACKGROUND

It is increasingly clear that asthma is not a single disease, but a disorder with vast heterogeneity in pathogenesis, severity, and treatment response. To date, 30 genomewide association studies (GWASs) of asthma have been performed, including by our group. However, most gene variants identified so far confer relatively small increments in risk and explain only a small proportion of familial clustering.

OBJECTIVE

To identify additional genetic determinants of susceptibility to asthma using a selected Japanese population with reduced tobacco smoking exposure.

METHODS

We performed a GWAS by genotyping a total of 480 098 single-nucleotide polymorphisms (SNPs) for a Japanese cohort consisting of 734 healthy controls and 240 patients with asthma who had smoked for no more than 10 pack-years. The SNP with the strongest association was genotyped in two other independent Japanese cohorts consisting of a total of 531 healthy controls and 418 patients with asthma who had smoked for no more than 10 pack-years. For the hyaluronan synthase 2 (HAS2) gene, we investigated SNP-gene associations using an expression quantitative trait loci (eQTL) database and also analysed its gene expression profiles in 13 different normal tissues.

RESULTS

In the discovery GWAS, a SNP located upstream of HAS2, rs7846389, showed the strongest statistical significance (P = 1.43 × 10(-7) ). In the two independent replication cohorts, rs7846389 was consistently associated with asthma (nominal P = 0.0152 and 0.0478 in the first and second replication cohorts, respectively). In the meta-analysis, association of rs7846389 with susceptibility to asthma reached the level of genomewide significance (P = 7.92 × 10(-9) ). This variant was strongly correlated with HAS2 mRNA expression. The strongest expression of the gene was detected in the lung.

CONCLUSIONS

Our study identified HAS2 as a novel candidate gene for susceptibility to adult asthma.

Seawater cultivation of freshwater cyanobacterium Synechocystis sp. PCC 6803 drastically alters amino acid composition and glycogen metabolism

Water use assessment is important for bioproduction using cyanobacteria. For eco-friendly reasons, seawater should preferably be used for cyanobacteria cultivation instead of freshwater. In this study, we demonstrated that the freshwater unicellular cyanobacterium Synechocystis sp. PCC 6803 could be grown in a medium based on seawater. The Synechocystis wild-type strain grew well in an artificial seawater (ASW) medium supplemented with nitrogen and phosphorus sources. The addition of HEPES buffer improved cell growth overall, although the growth in ASW medium was inferior to that in the synthetic BG-11 medium. The levels of proteins involved in sugar metabolism changed depending on the culture conditions. The biosynthesis of several amino acids including aspartate, glutamine, glycine, proline, ornithine, and lysine, was highly up-regulated by cultivation in ASW. Two types of natural seawater (NSW) were also made available for the cultivation of Synechocystis cells, with supplementation of both nitrogen and phosphorus sources. These results revealed the potential use of seawater for the cultivation of freshwater cyanobacteria, which would help to reduce freshwater consumption during biorefinery using cyanobacteria.

Alteration of cyanobacterial sugar and amino acid metabolism by overexpression hik8, encoding a KaiC-associated histidine kinase

Cyanobacteria possess circadian clocks consisting of KaiABC proteins, and circadian rhythm must closely relate to the primary metabolism. A histidine kinase, SasA, interacts with KaiC to transduce circadian signals and widely regulates transcription in Synechococcus sp. PCC 7942, although the involvement of SasA in primary metabolism has not been demonstrated at metabolite levels. Here, we generated a strain overexpressing hik8 (HOX80), an orthologue of SasA in Synechocystis sp. PCC 6803. HOX80 grew slowly under light conditions and lost viability under continuous dark conditions. Transcript levels of genes related to sugar catabolism remained higher in HOX80 under dark conditions. Metabolomic analysis revealed that under light conditions, glycogen was undetectable in HOX80, and there were decreased levels of metabolites of sugar catabolism and increased levels of amino acids, compared with those in the wild-type strain. HOX80 exhibited aberrant degradation of SigE proteins after a light-to-dark transition and immunoprecipitation analysis revealed that Hik8 directly interacts with KaiC1. The results of this study demonstrate that overexpression of hik8 widely alters sugar and amino acid metabolism, revealing the involvement of Hik8 in primary metabolism under both light and dark conditions in this cyanobacterium.

Surveillance and diagnostic algorithm for hepatocellular carcinoma proposed by the Liver Cancer Study Group of Japan: 2014 update

Surveillance and diagnostic algorithms for hepatocellular carcinoma (HCC) have already been described in guidelines published by the American Association for the Study of Liver Diseases (AASLD), the European Association for the Study of the Liver and the European Organisation for Research and Treatment of Cancer (EASL-EORTC), and the Japan Society of Hepatology (JSH), but the content of these algorithms differs slightly. The JSH algorithm mainly differs from the other two algorithms in that it is highly sophisticated and considers the functional imaging techniques of gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid-enhanced MRI (EOB-MRI) and Sonazoid contrast-enhanced ultrasound (CEUS) to be very important diagnostic modalities. In contrast, the AASLD and EASL-EORTC algorithms are less advanced and suggest that a diagnosis be made based solely on hemodynamic findings using dynamic CT/MRI and biopsy findings. A consensus meeting regarding the JSH surveillance and diagnostic algorithm was held at the 50th Liver Cancer Study Group of Japan Congress, and a 2014 update of the algorithm was completed. The new algorithm reaffirms the very important role of EOB-MRI and Sonazoid CEUS in the surveillance and diagnosis of liver cancer and is more sophisticated than those currently used in the United States and Europe. This is now an optimized algorithm that can be used to diagnose early-stage to classical HCC easily and highly accurately.

JSH Consensus-Based Clinical Practice Guidelines for the Management of Hepatocellular Carcinoma: 2014 Update by the Liver Cancer Study Group of Japan

The Clinical Practice Guidelines for the Management of Hepatocellular Carcinoma proposed by the Japan Society of Hepatology was updated in June 2014 at a consensus meeting of the Liver Cancer Study Group of Japan. Three important items have been updated: the surveillance and diagnostic algorithm, the treatment algorithm, and the definition of transarterial chemoembolization (TACE) failure/refractoriness. The most important update to the diagnostic algorithm is the inclusion of gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid-enhanced magnetic resonance imaging as a first line surveillance/diagnostic tool. Another significant update concerns removal of the term "lipiodol" from the definition of TACE failure/refractoriness.

Metabolomic analysis reveals rewiring of Synechocystis sp. PCC 6803 primary metabolism by ntcA overexpression

NtcA is a cAMP receptor protein-type transcription factor conserved among cyanobacteria and is essential for gene expression in response to nitrogen status. NtcA has been widely studied; however, no metabolomic analysis has been conducted using the ntcA mutant. Here, we generated a strain that overexpresses ntcA in Synechocystis sp. PCC 6803, named NOX10, and performed physiological, transcriptomic and metabolomic analyses. NOX10 grew faster than the wild-type strain under photoautotrophic conditions, but slower under light-activated heterotrophic conditions. Transcriptome analysis revealed that the expression of genes related to primary metabolism was altered by ntcA overexpression particularly under nitrogen-depleted conditions. Metabolomic analysis revealed that metabolite levels in sugar, purine/pyrimidine nucleotide, organic acid and amino acid metabolism were widely altered by ntcA overexpression. The protein levels of nitrogen-regulated transcriptional regulators were altered by ntcA overexpression during nitrogen starvation. These results demonstrate the alteration of primary metabolism by genetic engineering of NtcA, and they contribute to the current understanding of metabolic regulation of unicellular cyanobacteria.

Thrombocytopenia in pegylated interferon and ribavirin combination therapy for chronic hepatitis C

BACKGROUND

This study aimed to examine the therapeutic effect and prognostic indicators of pegylated interferon (PEG-IFN) and ribavirin (RBV) combination therapy in thrombocytopenic patients with chronic hepatitis C, hepatitis C virus (HCV)-related cirrhosis, and those who underwent splenectomy or partial splenic embolization (PSE).

METHODS

Of 326 patients with HCV-related chronic liver disease (252 with genotype 1b and 74 with genotype 2a/2b) treated with PEG-IFN/RBV, 90 were diagnosed with cirrhosis.

RESULTS

Regardless of the degree of thrombocytopenia, the administration rate was significantly higher in the splenectomy/PSE group compared to the cirrhosis group. However, in patients with genotype 1b, the sustained virological response (SVR) rate was significantly lower in the cirrhosis and the splenectomy/PSE groups compared to the chronic hepatitis group. No cirrhotic patients with platelets less than 80,000 achieved an SVR. Patients with genotype 2a/2b were more likely to achieve an SVR than genotype 1b. Prognostic factors for SVR in patients with genotype 1b included the absence of esophageal and gastric varices, high serum ALT, low AST/ALT ratio, and the major homo type of the IL28B gene. Splenectomy- or PSE-facilitated induction of IFN in patients with genotype 2a/2b was more likely to achieve an SVR by an IFN dose maintenance regimen. Patients with genotype 1b have a low SVR regardless of splenectomy/PSE. In particular, patients with a hetero/minor type of IL28B did not have an SVR.

CONCLUSIONS

Splenectomy/PSE for IFN therapy should be performed in patients expected to achieve a treatment response, considering their genotype and IL28B.

Nationwide survey in Japan regarding splenectomy/partial splenic embolization for interferon treatment targeting hepatitis C virus-related chronic liver disease in patients with low platelet count

AIM

In chronic liver disease associated with hepatitis C virus (HCV), a low platelet count is a major obstacle in carrying out interferon (IFN) treatment. We used a questionnaire to clarify the extent to which splenectomy/partial splenic embolization (PSE) is performed before IFN treatment, as well as the efficacy and complications thereof.

METHODS

Two questionnaires were distributed to 413 medical institutes in Japan specializing in the treatment of liver diseases, and responses were obtained from 204 institutes. Furthermore, a more detailed questionnaire was completed by 10 institutes that experienced cases of death.

RESULTS

In patients with HCV genotype 1b and a high viral load (HCV1b/High), the sustained viral response (SVR) rate was 28% for the splenectomy group and 22% for the PSE group, with no significant difference between these groups. In patients that were not HCV1b/High, the SVR rate was higher in those that underwent splenectomy (71%) compared to the PSE group (56%; P = 0.025). There were cases of death in seven of 799 splenectomy cases (0.89%) and four of 474 PSE cases (0.84%). Infectious diseases were involved in nine of 11 cases of death, with a peculiar patient background of Child-Pugh B (6/10) and an age of 60 years or greater (7/11).

CONCLUSION

The application of splenectomy/PSE before IFN treatment should be avoided in patients with poor residual hepatic function and/or elderly patients. In HCV1b/High patients, splenectomy/PSE should be performed only after selecting those in which IFN treatment should be highly effective.

Serum zinc value in patients with hepatitis virus-related chronic liver disease: association with the histological degree of liver fibrosis and with the severity of varices in compensated cirrhosis

The relationships between the serum mineral concentrations and the endoscopic findings of esophageal varices have been poorly investigated. In this study, we investigated hepatitis virus-positive patients who had undergone a liver biopsy (n = 576) and 75 patients with compensated cirrhosis in order to evaluate the association of the zinc value with the severity of liver fibrosis and esophageal varices. The mean zinc values decreased with the progression of fibrosis (METAVIR score; F0–1: 71.3 ± 11.3, F2: 68.9 ± 11.7, F3: 66.3 ± 11.8, F4: 63.9 ± 15.0). In the hepatitis virus-related compensated cirrhosis, the mean zinc value decreased with the severity of varices (patients without varices: 66.3 ± 12.6, patients with low-risk varices: 62.5 ± 13.7, patients with high-risk varices: 55.6 ± 13.0). The zinc value was significantly lower in patients with varices than in those without varices (59.3 ± 13.6 vs 66.3 ± 12.6, p<0.05). The zinc value was also significantly lower in the patients with a high risk of bleeding than in those with a low risk (55.6 ± 13.0 vs 64.6 ± 13.1, p<0.01). These findings suggest that the zinc value is not only an indicator of an abnormal metal metabolism, but is also a simple parameter associated with hepatitis virus-related various conditions, including the degree of liver fibrosis and the severity of esophageal varices in compensated cirrhosis.

Destabilization of the medial meniscus leads to subchondral bone defects and site-specific cartilage degeneration in an experimental rat model

OBJECTIVE

This study aimed to investigate subchondral bone changes using micro-computed tomography (micro-CT) and regional differences in articular cartilage degeneration, focusing on changes of cartilage covered by menisci, in the early phase using a destabilization of the medial meniscus (DMM) model.

METHOD

The DMM model was created as an experimental rat osteoarthritis (OA) model (12 weeks old; n = 24). At 1, 2, and 4 weeks after surgery, the rats were sacrificed, and knee joints were scanned using a Micro-CT system. Histological sections of the medial tibial plateau, which was divided into inner, middle, and outer regions, were prepared and scored using the modified OARSI scoring system. The cartilage thickness was also calculated, and matrix metalloproteinase 13 (MMP13), Col2-3/4c, and vascular endothelial growth factor (VEGF) expression was assessed immunohistochemically.

RESULTS

Subchondral bone defects were observed in the middle region, in which the cartilage thickness decreased over time after surgery, and these defects were filled with MMP13- and VEGF-expressing fibrous tissue. The OARSI score increased over time in the middle region, and the score was significantly higher in the middle region than in the inner and outer regions at 1, 2, and 4 weeks after surgery. Col2-3/4c and MMP13 expression was observed primarily in the meniscus-covered outer region, in which the cartilage thickness increased over time.

CONCLUSION

Loss of meniscal function caused cartilage degeneration and subchondral bone defects in the early phase site-specifically in the middle region. Furthermore, our results might indicate cartilage covered by menisci is easily degraded resulting in osmotic swelling of the cartilage in early OA.

Accuracy of spleen stiffness measurement in detection of esophageal varices in patients with chronic liver disease: systematic review and meta-analysis

BACKGROUND & AIMS

Spleen stiffness measurement (SSM) is a promising noninvasive alternative to esophagogastroduodenoscopy (EGD) that could be used in the diagnosis of esophageal varices (EV) in patients with cirrhosis. However, its overall diagnostic accuracy in various clinical settings is unknown. We conducted a systematic review and meta-analysis of studies that compared the accuracy of SSM with that of EGD in detecting EV in patients with chronic liver disease.

METHODS

Through a systematic search of bibliographic databases and conference proceedings, and contact with authors, we identified 12 studies that reported the accuracy of SSM, compared with EGD, in the diagnosis of any and/or clinically significant EV in adults with chronic liver disease. In a meta-analysis, we combined measures of test performance of individual studies.

RESULTS

Based on pooled estimates, SSM detected the presence of any EV with 78% sensitivity (95% confidence interval [CI], 75%-81%), 76% specificity (95% CI, 72%-79%), a positive likelihood ratio (LR) of 3.4 (95% CI, 2.3-4.9), a negative LR of 0.2 (95% CI, 0.1-0.4), and a diagnostic odds ratio of 19.3 (95% CI, 7.5-49.8). In a meta-analysis of 9 studies, SSM detected the presence of clinically significant EV with 81% sensitivity (95% CI, 76%-86%), 66% specificity (95% CI, 61%-69%), a positive LR of 2.5 (95% CI, 1.7-3.9), a negative LR of 0.2 (95% CI, 0.1-0.5), and a diagnostic odds ratio of 12.6 (95% CI, 5.5-28.7). There was significant heterogeneity among studies owing to differences in elastography techniques and study locations. The included studies that were at risk for spectrum bias, review bias, and disease progression bias.

CONCLUSIONS

Based on a meta-analysis, current techniques for measuring spleen stiffness are limited in their accuracy of EV diagnosis; these limitations preclude widespread use in clinical practice at this time.

Pathway-level acceleration of glycogen catabolism by a response regulator in the cyanobacterium Synechocystis species PCC 6803

Response regulators of two-component systems play pivotal roles in the transcriptional regulation of responses to environmental signals in bacteria. Rre37, an OmpR-type response regulator, is induced by nitrogen depletion in the unicellular cyanobacterium Synechocystis species PCC 6803. Microarray and quantitative real-time polymerase chain reaction analyses revealed that genes related to sugar catabolism and nitrogen metabolism were up-regulated by rre37 overexpression. Protein levels of GlgP(slr1367), one of the two glycogen phosphorylases, in the rre37-overexpressing strain were higher than those of the parental wild-type strain under both nitrogen-replete and nitrogen-depleted conditions. Glycogen amounts decreased to less than one-tenth by rre37 overexpression under nitrogen-replete conditions. Metabolome analysis revealed that metabolites of the sugar catabolic pathway and amino acids were altered in the rre37-overexpressing strain after nitrogen depletion. These results demonstrate that Rre37 is a pathway-level regulator that activates the metabolic flow from glycogen to polyhydroxybutyrate and the hybrid tricarboxylic acid and ornithine cycle, unraveling the mechanism of the transcriptional regulation of primary metabolism in this unicellular cyanobacterium.

Hemodynamic analysis and treatment of an enlarging extrahepatic portal aneurysm: report of a case

Aneurysms in the portal venous system are relatively rare. We report the case of an extrahepatic portal venous aneurysm, detected incidentally by ultrasonography. The patient, a 75-year-old woman, was initially observed over 18 months, during which time, the aneurysm grew from 36 mm × 32 mm to 51 mm × 37 mm in size, without symptoms. Hemodynamic analysis employing computational flow dynamics technique showed obvious turbulence in the aneurysm, and the wall shear stress (WSS) against that part of the aneurysmal wall was greater than in other sites. To prevent complications such as spontaneous rupture and portal vein thrombosis, the aneurysm was resected, with reconstruction of the portal trunk. While careful follow-up is sufficient for most portal venous aneurysms, its enlargement could indicate possible spontaneous rupture. The increased WSS against part of the aneurysmal wall most likely accounts for the aneurysm enlargement in this case.

An Increased Ratio of Glycated Albumin to HbA1c Is Associated with the Degree of Liver Fibrosis in Hepatitis B Virus-Positive Patients

Background. In hepatitis B virus- (HBV-) positive patients, the relationship between the metabolic variables and histological degree of liver fibrosis has been poorly investigated. Methods. A total of 176 HBV-positive patients were assessed in whom the ratios of glycated albumin-to-glycated hemoglobin (GA/HbA1c) were calculated in order to investigate the relationship with the degree of liver fibrosis. Results. The GA/HbA1c ratio increased in association with the severity of fibrosis (METAVIR scores: F0-1: 2.61 ± 0.24, F2: 2.65 ± 0.24, F3: 2.74 ± 0.38, and F4: 2.91 ± 0.63). The GA/HbA1c ratios were inversely correlated with four variables of liver function: the prothrombin time (PT) percentage (P < 0.0001), platelet count (P < 0.0001), albumin value (P < 0.0001), and cholinesterase value (P < 0.0001). The GA/HbA1c ratio was positively correlated with two well-known markers of liver fibrosis, FIB-4 (P < 0.0001) and the AST-to-platelet ratio index (APRI) (P < 0.0001). Furthermore, the GA/HbA1c showed better correlations with two variables of liver function (PT percentage and cholinesterase value) than did FIB-4 and with all four variables than did the APRI. Conclusion. The GA/HbA1c ratio is associated with the degree of liver fibrosis in HBV-positive patients.

Protein-bound polysaccharide-K reduces the proportion of regulatory T cells in vitro and in vivo

Regulatory T cells (Tregs) play an important role in maintaining immunological tolerance. However, this mechanism is one of the major obstacles to overcome when attempting to improve antitumor immunity. Protein-bound polysaccharide‑K (PSK) has been used clinically as an antitumor drug, and one of its antitumor mechanisms involves improvement of the tumor-induced immunosuppressive state. Therefore, we investigated whether PSK affects Tregs in vitro and in vivo. In the in vitro study, CD4⁺CD25⁻ cells were separated from normal mouse spleen and cultured with or without PSK in the presence of TGF-β. Although TGF-β induced CD4⁺CD25⁺Foxp3⁺ Tregs, PSK reduced the proportion of TGF-β-induced Tregs. In the in vivo study, BALB/c mice were injected subcutaneously with methylcholanthrene-induced fibrosarcoma (Meth A) cells on day 0, and were administered PSK (50 mg/kg) intraperitoneally from day 1, three times per week. After 4 weeks, the tumor volume, the proportion of Tregs and the CD8+/Treg ratio in the spleen, plasma TGF-β concentration, and IFN-γ production by spleen cells were measured. PSK significantly reduced tumor growth, the proportion of Tregs in the spleen and the plasma TGF-β concentration, and significantly increased the CD8+/Treg ratio in the spleen and IFN-γ production by spleen cells. The reduction of the TGF-β concentration in blood by PSK appears to decrease the proportion of Tregs in lymphoid organs and to augment antitumor immunity.

Pleiotropic effect of sigE over-expression on cell morphology, photosynthesis and hydrogen production in Synechocystis sp. PCC 6803

Over-expression of sigE, a gene encoding an RNA polymerase sigma factor in the unicellular cyanobacterium Synechocystis sp. PCC 6803, is known to activate sugar catabolism and bioplastic production. In this study, we investigated the effects of sigE over-expression on cell morphology, photosynthesis and hydrogen production in this cyanobacterium. Transmission electron and scanning probe microscopic analyses revealed that sigE over-expression increased the cell size, possibly as a result of aberrant cell division. Over-expression of sigE reduced respiration and photosynthesis activities via changes in gene expression and chlorophyll fluorescence. Hydrogen production under micro-oxic conditions is enhanced in sigE over-expressing cells. Despite these pleiotropic phenotypes, the sigE over-expressing strain showed normal cell viability under both nitrogen-replete and nitrogen-depleted conditions. These results provide insights into the inter-relationship among metabolism, cell morphology, photosynthesis and hydrogen production in this unicellular cyanobacterium.

Association of amino acid imbalance with the severity of liver fibrosis and esophageal varices

BACKGROUND

The relationships between the metabolic parameters and the endoscopic findings of esophageal varices have been poorly investigated. We investigated the association of the branched-chain amino acids to tyrosine ratio (BTR) with the severity of liver fibrosis and esophageal varices.

MATERIAL AND METHODS

We studied hepatitis C virus (HCV)-positive chronic liver disease patients who had undergone liver biopsy (n = 149). The relationship between the BTR values and the liver fibrotic stage was investigated. We also studied whether the BTR value was associated with the presence and bleeding risk of varices in patients with HCV-related compensated cirrhosis.

RESULTS

The mean values of the BTR decreased with the progression of the fibrosis (METAVIR score: F0-1: 6.40 ± 1.19; F2: 5.85 ± 1.33; F3: 5.24 ± 0.97, F4: 4.78 ± 1.14). In the 58 patients with HCV-related compensated cirrhosis, the mean values of the BTR decreased with the severity of varices (patients without varices: 5.01 ± 1.15, patients with a low-risk varices: 4.42 ± 1.06, patients with a high-risk varices: 3.86 ± 1.02). The BTR value was significantly lower in the patients with varices than in those without varices (4.17 ± 1.07 vs. 5.01 ± 1.15, P < 0.01). The BTR value was also significantly lower in the patients with a high risk of hemorrhage than in those with a low risk (3.86 ± 1.02 vs. 4.78 ± 1.14, P < 0.01). Furthermore, the BTR value was the most significantly different parameter, with the smallest P-value among all the factors examined, including the platelet count and albumin level.

CONCLUSION

A decreased BTR value was found to be associated with the progression of liver fibrosis and severity of varices.

Regional hepatic regeneration after liver resection correlates well with preceding changes in the regional portal circulation in humans

BACKGROUND AND AIMS

While portal hemodynamics largely affects the liver regeneration after partial hepatectomy, whether the remnant liver homogeneously regenerates is unclear, especially in humans. We hypothesized that change in flow distribution varies in each remnant portal branch after liver resection in humans and the liver consequently regenerates heterogeneously.

METHODS

Twenty-two patients who underwent anatomical hepatic resection preserving intact drainage veins were analyzed. Based on perioperative contrast-enhanced computed tomography, the regional hepatic regeneration in each segment was analyzed using a region growing software. The perioperative change in the distribution of blood flow in each portal branch was assessed using the computational flow dynamics technique. The correlation between the change in the portal flow distribution and the later regional hepatic regeneration was investigated.

RESULTS

The distribution of portal blood flow in each remnant branch largely changed at 2 weeks (71-389 %). Each remnant segment also heterogeneously regenerated at 3 months (85-204 %). Meanwhile, a good correlation between the regional regeneration rate at 3 months and the relative change in the flow distribution in each circulating portal branch at 2 weeks was detected in each patient (r = 0.74-0.99).

CONCLUSIONS

After partial hepatectomy, the change in blood flow varies in each remnant portal branch and the liver heterogeneously regenerates in humans. The good correlation between the earlier change in the portal flow distribution and the later regional hepatic regeneration strongly suggests that the portal venous flow most likely regulates the non-uniform liver regeneration after hepatic resection in humans.

The influence of aminotransferase levels on liver stiffness assessed by Acoustic Radiation Force Impulse Elastography: a retrospective multicentre study

BACKGROUND

Acoustic Radiation Force Impulse Elastography is a new method for non-invasive evaluation of liver fibrosis.

AIM

To evaluate the impact of elevated alanine aminotransferase levels on liver stiffness assessment by Acoustic Radiation Force Impulse Elastography.

METHODS

A multicentre retrospective study including 1242 patients with chronic liver disease, who underwent liver biopsy and Acoustic Radiation Force Impulse. Transient Elastography was also performed in 512 patients.

RESULTS

The best Acoustic Radiation Force Impulse cut-off for predicting significant fibrosis was 1.29 m/s in cases with normal alanine aminotransferase levels and 1.44 m/s in patients with alanine aminotransferase levels>5 × the upper limit of normal. The best cut-off for predicting liver cirrhosis were 1.59 and 1.75 m/s, respectively. Acoustic Radiation Force Impulse cut-off for predicting significant fibrosis and cirrhosis were relatively similar in patients with normal alanine aminotransferase and in those with alanine aminotransferase levels between 1.1 and 5 × the upper limit of normal: 1.29 m/s vs. 1.36 m/s and 1.59 m/s vs. 1.57 m/s, respectively. For predicting cirrhosis, the Transient Elastography cut-offs were significantly higher in patients with alanine aminotransferase levels between 1.1 and 5 × the upper limit of normal compared to those with normal alanine aminotransferase: 12.3 kPa vs. 9.1 kPa.

CONCLUSION

Liver stiffness values assessed by Acoustic Radiation Force Impulse and Transient Elastography are influenced by high aminotransferase levels. Transient Elastography was also influenced by moderately elevated aminotransferase levels.