Arrival time parametric imaging using Sonazoid-enhanced ultrasonography is useful for the detection of spoke-wheel patterns of focal nodular hyperplasia smaller than 3 cm

It is considered difficult to make a definitive diagnosis of focal nodular hyperplasia (FNH) of <3 cm when using conventional diagnostic imaging modalities. Typical FNH imaging findings are: i) central scar formation, ii) nutrient vessels extending radially from the center and iii) the presence of Kupffer cells. In a clinical setting, identification of a spoke-wheel pattern formed by nutrient vessels extending radially is a key feature in the diagnosis of FNH. In this study, we investigated the detection rate of spoke-wheel patterns of FNH <3 cm using arrival time parametric imaging (At-PI) technology with Sonazoid-enhanced ultrasonography (US). Five patients with FNH <3 cm who had undergone Sonazoid-enhanced US at the Toho University Omori Medical Center between February 2008 and March 2009 were included in the study. The mean tumor diameter was 20.2±7.2 mm. Lesions were enhanced with 0.5 ml Sonazoid US contrast agent and a video of the procedure was saved and used for At-PI analysis of contrast agent dynamics in FNH. Three ultrasonographic specialists examined the images and made a diagnosis of FNH based on the findings of spoke-wheel patterns. Similarly, micro-flow imaging (MFI) was performed to evaluate the contrast agent dynamics in FNH. Using MFI, FNH was diagnosed in 3 of the 5 cases by the three specialists, whereas At-PI enabled the identification of spoke-wheel patterns in all 5 cases. At-PI using Sonazoid-enhanced US is superior for detecting spoke-wheel patterns of FNH <3 cm.

Right hepatic artery pseudoaneurysm complicating acute pancreatitis: a case report

OBJECTIVE

To report a rare case of right hepatic artery pseudoaneurysm complicating acute pancreatitis based upon imaging findings obtained before and after the development of pseudoaneurysm.

CLINICAL PRESENTATION AND INTERVENTION

A 32-year-old male with a history of acute pancreatitis 1 year prior was readmitted for acute pancreatitis. Computed tomography (CT) and angiography after admission revealed pseudoaneurysm of the right hepatic artery. Transcatheter arterial embolization with coils was used to successfully treat the pseudoaneurysm. A CT and angiography 1 year earlier did not reveal any pseudoaneurysm.

CONCLUSION

This patient with a rare right hepatic artery pseudoaneurysm complicating acute pancreatitis was successfully treated with coil embolization.

Short-term effects and early complications of balloon-occluded retrograde transvenous obliteration for gastric varices

The short-term effects of balloon-occluded retrograde transvenous obliteration (BRTO) to treat gastric varices were evaluated by using computed tomography (CT) and gastroscopy (GF). The subjects were 77 patients who underwent BRTO to treat gastric varices. The short-term effects of BRTO were investigated with regard to ascites, pleural effusion, venous thrombus, and esophageal varices by comparing the findings of CT and GF performed within one month before and after BRTO. The mean duration of followup was 960.1 days. Ascites and pleural effusion were exacerbated after BRTO in 26 (33.8%) and 31 (40.3%), respectively. A significant difference in ascites exacerbation was noted in patients with hypoalbuminemia and a high Child-Pugh score, and a significant difference in exacerbation of pleural effusion was noted in patients with hypoalbuminemia. Venous thrombus was noted in 7 patients (9.1%). Esophageal varices were exacerbated in 14 (21.2%) of the 66 patients. The 2-year survival rate was 720 days, and significant differences were noted in the Child-Pugh classification and the concomitance of hepatocellular carcinoma (HCC) on multivariate analysis of prognosis-related factors. Conclusion. The frequencies of exacerbation of ascites, pleural effusion, and esophageal varices after BRTO were high but these may not be related to survival.

Risk factors for the local recurrence of hepatocellular carcinoma after single-session percutaneous radiofrequency ablation with a single electrode insertion

Radiofrequency ablation (RFA) is a new local therapy for hepatocellular carcinoma (HCC). In this study, we investigated the risk factors associated with local recurrence of HCC after single-session RFA with a single electrode insertion. From April 2003 to December 2007, we treated 138 HCC lesions by single-session RFA with a single electrode insertion using the Cool-tip RFA, RTC 2000 and RTC 3000 Systems. Risk factors for the local recurrence of these lesions and complications after RFA were analyzed. The mean size of the 138 lesions was 16.9±5.4 mm in diameter (range 7-33 mm). Local recurrence rates were 6.6 and 22.0% at 1 and 2 years, respectively, during the mean follow-up period of 16.4 months. Univariate analysis showed that tumor diameter (≥20 mm), tumor location, pre-treatment AFP-L3 fraction level and ablation pattern were significant variables. Multivariate analysis of these four variables identified only the tumor diameter as an independent risk factor for local recurrence. Complications occurred in 2.2% of the lesions (3/138). Single-session RFA is an effective treatment for HCC in that it reduces serious complications. This study demonstrated that a tumor size ≥20 mm influenced the local recurrence of single-session RFA with a single electrode insertion.

Analysis of patients with tumor seeding after percutaneous radiofrequency ablation of hepatocellular carcinoma

To determine the incidence and risk factors associated with tumor seeding after radiofrequency ablation (RFA) of hepatocellular carcinoma (HCC), 781 lesions from 352 patients who had undergone ultrasound (US)-guided RFA at our hospital between April 1999 and December 2005 were examined. Of these patients, 6 presented HCC lesions (6 lesions in total) and tumor seeding (7 seedings in total), which were analyzed. RFA using RITA 500 PA, the Cool-tip RFA System or the RTC 2000 System was performed. RFA sessions were repeated until complete necrosis was confirmed by imaging. Subsequently, follow-up was performed every 3-4 months by means of computed tomography (CT) and US scans. The 6 patients were retrospectively analyzed for patient characteristics, CT and histopathological findings, RFA method and complications, and clinical and imaging progress and outcome. Of the 6 lesions, 2 were in a subcapsular location at S7. Mean tumor diameter was 23.3±9 mm. Tumor biopsies indicated that 1 of the 6 lesions was well-differentiated, 4 were moderately-differentiated, and 1 was undifferentiated. The RITA 500 PA was used in 2 cases, and the Cool-tip RFA System in 4. Seeding was identified 14.6±13 months after RFA. Four of the cases with seeding were located on the abdominal wall, 2 on the thoracic wall and 1 in the Douglas pouch. Four of the patients underwent surgical resection, 1 radiation, and 1 conservative treatment for seeding. Five of the 6 patients died 12.6±9 months after seeding was detected, with the exception having undergone surgical treatment. The seeding risks identified in this study include treatment of subcapsular lesions and patient treatment over multiple sessions. The selection of the proper RFA system to avoid multiple sessions and the use of ablation technique are important for the prevention of seeding. Additionally, long-term follow-up after RFA by extensive imaging of the pelvic cavity and the thoracoabdominal wall is needed.

Heterotopic Pancreas of the Jejunum Incidentally Detected by Preoperative Abdominal CT: Report of Two Cases and Review of the Literature

Heterotopic pancreas (HP) is typically an asymptomatic malformation that can present anywhere along the gastrointestinal tract. It is often detected incidentally on surgery for other diseases or autopsy. We encountered 2 patients with jejunal HP incidentally detected by computed tomography (CT) performed for close evaluation of other diseases. In a 57-year-old woman diagnosed with reactive lymphoid hyperplasia on the dorsal portion of the pancreas head, CT detected a 15 mm oval-shaped submucosal lesion at the jejunum. In an 87-year-old woman diagnosed with type 2 adenocarcinoma occupying the sigmoid colon, CT detected a round-shaped submucosal tumor 15 mm in diameter in the jejunum. Both cases were histologically diagnosed as type 1 HP according to the classification by Heinrich. Contrast-enhanced CT revealed that the CT analyses of HP and pancreatic parenchyma were nearly identical in the arterial phase, but in the equilibrium phase, contrast enhancement persisted longer in HP than in the pancreatic parenchyma. There has been no report of asymptomatic jejunal HP preoperatively diagnosed by CT. These cases are presented with a review of the literature, particularly focusing on CT findings.

Recurrence incidence of small HCC in cirrhosis patients by ablation versus injection

BACKGROUND/AIMS

The incidence of local recurrence of hypervascular hepatocellular carcinoma (HCC) (15 mm or less) was compared retrospectively between a group treated with radiofrequency ablation (RFA) using cool-tip (Radionics, USA) 10-mm electrodes and a group treated with percutaneous ethanol injection (PEI).

METHODOLOGY

There were 23 patients who were treated for a total of 25 tumors during a 3-year period at our hospital. Ten of the tumors (11.1 +/- 2.7mm) were treated with RFA using cool-tip 10-mm electrodes and 15 tumors (10.6 +/- 2.7 mm) were treated with PEI. After treatment, progression was evaluated in enhanced CT scans every 3-6 months to confirm presence or absence of local recurrence.

RESULTS

The number of recurrences, mean observation period, and mean recurrence period in the RFA group were 2 (20%), 6.6 months, and 6 months. The number of recurrences, mean observation period, and mean recurrence period in the PEI group were 2 (13.3%), 19.1 months, and 18 months. The period between treatment and recurrence tended to be longer in the PEI group than in the RFA group to be significant p < 0.05.

CONCLUSIONS

The results suggest that PEI treatment is more effective in local treatment of hypervascular HCC with tumor diameters of 15 mm or less.

Cool-tip 10-mm electrode useful for radiofrequency ablation of hepatocellular carcinoma

BACKGROUND/AIMS

Whether a cool-tip 10mm electrode is useful for radiofrequency ablation (RFA) of hepatocellular carcinoma (HCC) has not been established. Accordingly, the present study goal was to determine this electrode is indicated for RFA of HCC.

METHODOLOGY

This study was conducted with 30 HCC patients who were treated with a cool-tip 10-mm electrode over a period of about 3 years. Ten had hypervascular HCC nodules and 20 had hypovascular HCC nodules; mean tumor diameter was 10.5 +/- 1.8mm. Patients underwent follow-up CT scans every 3 to 6 months to detect local progression.

RESULTS

Of the 30 lesions, 4 (13.3%) showed local progression. Enhanced CT imaging of the four cases with local progression revealed that two had hypervascular HCC. The remaining two cases had hypovascular HCC.

CONCLUSIONS

The present study results suggest that, RFA with a cool-tip 10-mm electrode is indicated in cases of hypovascular HCC nodules if the lesion diameter is no more than 10mm. In addition, in order to avoid skin burns, only lesions at a depth of at least 16mm below the liver surface are suitable for this treatment. Because of its lesser invasiveness, the cool-tip 10-mm electrode appears to be more useful than other, more powerful, devices in patients with hepatic carcinoma.

Changes of cytokines in cirrhosis patients with advanced hepatocellular carcinoma treated by intra-arterial chemotherapy

INTRODUCTION

Tumor necrosis factor (TNF) induces cancer cell-specific apoptosis by binding to a TNF-related apoptosis-inducing ligand. Binding of the Fas ligand on cytotoxic T lymphocytes to the Fas receptor on hepatocytes is also known to induce apoptosis. The aim of this study was to clarify changes of cytokines in patients with liver cirrhosis (LC) and advanced hepatocellular carcinoma (aHCC) receiving intra-arterial combination chemotherapy.

METHODS

Twenty-one adult Japanese LC patients with aHCC received intra-arterial combination chemotherapy. The serum levels of TNF-alpha, soluble TNF receptor-I (sTNFr-I), soluble Fas ligand (sFas L), and soluble Fas (sFas) were evaluated.

RESULTS

Thirteen of the 21 patients (group R) showed an objective response, while the other eight patients (group N) showed no response. The serum level of TNF-alpha was lower after chemotherapy than before chemotherapy in group N, but there was no difference of serum sTNFr-I levels between before and after chemotherapy and there were also no differences between the two groups. The serum sFas levels were higher after chemotherapy than before chemotherapy in group N, while there was no difference among groups.

CONCLUSIONS

These results indicate that a high serum TNF-alpha level and a low serum sFas level might be important for successful combined arterial chemotherapy in LC patients with aHCC.

Effects of Time-Varying Magnetic Fields on Transient increase in Intracellular Ca²⁺Concentration of Cultured Cells

We tested the effects of some kinds of time-varying magnetic fields (0-1.2T) on neurotransmitter-induced transient increases in intracellular Ca²⁺concentration ([Ca²⁺]) of cultured chromaffin and HeLa cells. After these cells were exposed for 2 hours to these magnetic fields, transient increases in [Ca²⁺]i by addition of acetylcholine or histamine were measured. In control cells, after addition of these neurotransmitters [Ca²⁺]i was increased immediately and then decreased with time in both cells. But, addition of these drugs to the magnetic fields exposed cells increased [Ca²⁺]i to a level similar to that for control cells. These results suggest that the transient increases in [Ca²⁺]i were not significantly influenced by the magnetic fields used in this experiment.

Intracellular cytokine analysis of CD4-positive T cells predictive of sustained response to interferon therapy for patients with chronic hepatitis C

We investigated whether the measurement of serum interleukin 18 (IL-18) and intracellular cytokine analysis of peripheral blood CD4-positive T cells (ICA-CD4+ Tc) of chronic hepatitis C (CH-C) patients before and two weeks after interferon (IFN) administration are useful for predicting sustained response to IFN. Twenty-nine CH-C patients received IFN every day for two weeks and three times a week for 22 weeks. Patients were divided into two groups: responders, in whom serum HCV-RNA was undetectable at the end of the follow-up (week 48), and nonresponders, in whom any other patterns were seen. Before and two weeks after IFN administration, serum IL-18 and ICA-CD4+ Tc as described by Jung et al were measured. Serum IL-18 and the relative prevalence of IFN-gamma+ and IL-4+, IFN-gamma+ and IL-4 (Th-1), and IFN-gamma- and IL-4+ cells in the responders were significantly increased, but only the relative prevalence of Th-1 cells in the nonresponders was increased two weeks after IFN therapy. In conclusion, ICA-CD4+ Tc and the measurement of serum IL-18 might be useful for predicting IFN therapy by comparing the results between before and two weeks after IFN.

Primary retroperitoneal pure yolk-sac tumor in an adult male

Pure extragonadal tumors are rare in adult males. A 24-year-old male with an extremely high level of serum alpha-fetoprotein (32.795 ng/ml) was diagnosed by abdominal computed tomography as having a retroperitoneal tumor. A case of primary retroperitoneal pure yolk-sac tumor in an adult male is described.

Heterochronous development of intrahepatic cholangiocellular carcinoma following hepatocellular carcinoma in a hepatitis B virus carrier

A 68-year-old Japanese woman was admitted to our hospital in September 1995, because of a mass detected by ultrasonography during a follow-up examination for chronic hepatitis B. Hepatocellular carcinoma (HCC) in the right liver lobe was diagnosed based on imaging studies and elevated alpha-fetoprotein (AFP). Percutaneous ethanol injection therapy (PEIT) was performed. PEIT was repeated in November 1998, because the tumor had enlarged and serum AFP was re-elevated. Follow-up ultrasonography (US) demonstrated low echoic mass in the left liver lobe in August 1999; serum AFP was normal, but serum carbohydrate antigen 19-9 (CA19-9) was elevated to 420 U/ml. In October 1999, radiofrequency interstitial tissue ablation (RITA) was performed after tumor biopsy. Pathological findings revealed adenocarcinoma and pathological diagnosis was made as intrahepatic cholangiocellular carcinoma (ICC). Three weeks later, her serum CA19-9 was remarkably decreased (180 U/ml). The patient has been well for 5 months. Her latest AFP and CA19-9 in the serum were 2 ng/ml and 89 U/ml, respectively. The incidence of double cancer in the liver is rare. This is also the first case report to discuss ICC treated with RITA.

p300 forms a stable, template-committed complex with chromatin: role for the bromodomain

The nature of the interaction of coactivator proteins with transcriptionally active promoters in chromatin is a fundamental question in transcriptional regulation by RNA polymerase II. In this study, we used a biochemical approach to examine the functional association of the coactivator p300 with chromatin templates. Using in vitro transcription template competition assays, we observed that p300 forms a stable, template-committed complex with chromatin during the transcription process. The template commitment is dependent on the time of incubation of p300 with the chromatin template and occurs independently of the presence of a transcriptional activator protein. In studies examining interactions between p300 and chromatin, we found that p300 binds directly to chromatin and that the binding requires the p300 bromodomain, a conserved 110-amino-acid sequence found in many chromatin-associated proteins. Furthermore, we observed that the isolated p300 bromodomain binds directly to histones, preferentially to histone H3. However, the isolated p300 bromodomain does not bind to nucleosomal histones under the same assay conditions, suggesting that free histones and nucleosomal histones are not equivalent as binding substrates. Collectively, our results suggest that the stable association of p300 with chromatin is mediated, at least in part, by the bromodomain and is critically important for p300 function. Furthermore, our results suggest a model for p300 function that involves distinct activator-dependent targeting and activator-independent chromatin binding activities.

Hepatic abscess as a complication of the sump syndrome

We report a case of hepatic abscess associated with the sump syndrome. The patient was a 66-year-old woman who had undergone cholecystectomy and side-to-side choledochoduodenostomy for a common bile duct (CBD) stone in 1983, and who presented with fever and right lower chest pain. A hepatic abscess was diagnosed; after it was drained, percutaneous transhepatic biliary drainage was performed. Bacteriological studies revealed the presence of Bacteroides fragilis and Streptococcus intermedius in the pus in the hepatic abscess cavity, and Klebsiella pneumoniae and Pseudomonas aeruginosa in the bile. The hepatic abscess and cholangitis rapidly resolved in response to two drainage procedures. At surgery, simple closure of the anastomosis was performed, because free drainage was observed from the distal CBD into the duodenum, despite the existence of a periampullary diverticulum.

p300-mediated acetylation facilitates the transfer of histone H2A-H2B dimers from nucleosomes to a histone chaperone

We have used a purified recombinant chromatin assembly system, including ACF (Acf-1 + ISWI) and NAP-1, to examine the role of histone acetylation in ATP-dependent chromatin remodeling. The binding of a transcriptional activator (Gal4-VP16) to chromatin assembled using this recombinant assembly system dramatically enhances the acetylation of nucleosomal core histones by the histone acetyltransferase p300. This effect requires both the presence of Gal4-binding sites in the template and the VP16-activation domain. Order-of-addition experiments indicate that prior activator-meditated, ATP-dependent chromatin remodeling by ACF is required for the acetylation of nucleosomal histones by p300. Thus, chromatin remodeling, which requires a transcriptional activator, ACF and ATP, is an early step in the transcriptional process that regulates subsequent core histone acetylation. Glycerol gradient sedimentation and immunoprecipitation assays demonstrate that the acetylation of histones by p300 facilitates the transfer of H2A-H2B from nucleosomes to NAP-1. The results from these biochemical experiments suggest that (1) transcriptional activators (e.g., Gal4-VP16) and chromatin remodeling complexes (e.g., ACF) induce chromatin remodeling in the absence of histone acetylation; (2) transcriptional activators recruit histone acetyltransferases (e.g., p300) to promoters after chromatin remodeling has occurred; and (3) histone acetylation is important for a step subsequent to chromatin remodeling and results in the transfer of histone H2A-H2B dimers from nucleosomes to a histone chaperone such as NAP-1. Our results indicate a precise role for histone acetylation, namely to alter the structure of nucleosomes (e.g., facilitate the loss of H2A-H2B dimers) that have been remodeled previously by the action of ATP-dependent chromatin remodeling complexes. Thus, transcription from chromatin templates is ordered and sequential, with precise timing and roles for ATP-dependent chromatin remodeling, subsequent histone acetylation, and alterations in nucleosome structure.

Amino acid sequences of hemoglobin from guinea fowl (Numida meleagri) and California quail (Lophortyx californica) with phylogenetic analysis of major groups of Galliformes

We determined the complete amino acid sequences of the hemoglobin of two species, guinea fowl and California quail, in Galliformes from intact globin chain and chemical cleavage fragments in order to analyze the molecular evolution of hemoglobin for the classification of Galliformes. Galliformes have two types of hemoglobin components, HbA and HbD, which consist of identical beta chain and different alpha chains. The sequences are similar to globin chains of Galliformes reported previously. These sequences were compared with those of other Galliformes (Phasianidae, Meleagrididae) using duck and goshawk as out-groups. The phylogenetic tree of major groups of Galliformes based on hemoglobin was similar to the tree model produced based on the amino acid sequence of lysozyme c.

Effects on Rb(+)(K+) uptake of HeLa cells in a high K(+) medium of exposure to a switched 1.7 Tesla magnetic field

Effects of a switched, time-varying 1.7 T magnetic field on Rb(+)(K+) uptake by HeLa S3 cells incubated in an isosmotic high K(+) medium were examined. The magnetic flux density was varied intermittently from 0.07-1.7 T at an interval of 3 s. K(+) uptake was activated by replacement of normal medium by high K(+) medium. A membrane-permeable Ca(2+) chelating agent (BAPTA-AM) and Ca(2+)-dependent K(+) channel inhibitors (quinine, charibdotoxin, and iberiotoxin) were found to reduce the Rb(+)(K+) uptake by about 30-40%. Uptake of K(+) that is sensitive to these drugs is possibly mediated by Ca(2+)-dependent K(+) channels. The intermittent magnetic field partly suppress ed the drug-sensitive K(+) uptake by about 30-40% (P < 0.05). To test the mechanism of inhibition by the magnetic fields, intracellular Ca(2+) concentration ([Ca(2+)]c) was measured using Fura 2-AM. When cells were placed in the high K(&plus;) medium, [Ca(2+)]c increased to about 1.4 times the original level, but exposure to the magnetic fields completely suppressed the increase (P < 0.01). Addition of a Ca(2+) ionophore (ionomycin) to the high K(+) medium increased [Ca(2+)]c to the level of control cells, regardless of exposure to the magnetic field. But the inhibition of K(+) uptake by the magnetic fields was not restored by addition of ionomycin. Based on our previous results on magnetic field-induced changes in properties of the cell membrane, these results indicate that exposure to the magnetic fields partly suppresses K(+) influx, which may be mediated by Ca(2+)-dependent K(+) channels. The suppress ion of K(+) fluxes could relate to a change in electric properties of cell surface and an inhibition of Ca(2+) influx mediated by Ca(2+) channels of either the cell plasma membrane or the inner vesicular membrane of intracellular Ca(2+) stores.