[Hyperplastic hepatic nodules in a case of idiopathic portal hypertension: changes in imaging findings during a 6-year follow-up].

A 22-year-old man had been given a diagnosis of idiopathic portal hypertension in childhood. In June 2001, a hepatic nodule which gradually increased in size over the next 2 years, was detected in the left hepatic lobe. In February 2003, a left lateral segmentectomy was performed. Histological examination of the nodules suggested focal nodular hyperplasia (FNH)-like hyperplasia. Computerized tomography performed 2 years later showed other hepatic nodules, and a liver biopsy was performed. Histopathological examination conducted at this time also suggested FNH-like hyperplasia. Owing to the substantial enlargement of the nodules and frequent recurrence, it can be difficult to distinguish between benign and malignant lesions.

[Bacteria isolated from surgical infections and their susceptibility to antimicrobial agents--special reference to bacteria isolated between April 2007 and March 2008].

Bacteria isolated from infections in abdominal surgery during the period from April 2007 to March 2008 were investigated in a multicenter study in Japan, and the following results were obtained. In this series, 707 strains including 24 strains of Candida spp. were isolated from 181 (79.0%) of 229 patients with surgical infections. Three hundred and ninety-five strains were isolated from primary infections, and 288 strains were isolated from postoperative infections. From primary infections, anaerobic Gram-negative bacteria were predominant, followed by aerobic Gram-negative bacteria, while from postoperative infections aerobic Gram-positive bacteria were predominant, followed by anaerobic Gram-negative bacteria. Among aerobic Gram-positive bacteria, the isolation rate of Enterococcus spp. was highest, followed by Streptococcus spp., and Staphylococcus spp. in this order, from primary infections, while Enterococcus spp. was highest, followed by Staphylococcus spp. from postoperative infections. Among aerobic Gram-negative bacteria, Escherichia coli was the most predominantly isolated from primary infections, followed by Klebsiella pneumoniae, Pseudomonas aeruginosa and Enterobacter cloacae, in this order, and from postoperative infections, P. aeruginosa was most predominantly isolated, followed by E. cloacae, E. coli and K. pneumoniae. Among anaerobic Gram-positive bacteria, the isolation rate of Parvimonas micra was the highest from primary infections, followed by Streptococcus constellatus and Gemella morbillorum, and from postoperative infections, Anaerococcus prevotii was most predominantly isolated. Among anaerobic Gram-negative bacteria, the isolation rate of both Bacteroides fragilis and Bilophila wadsworthia were the highest from primary infections, followed by Bacteroides thetaiotaomicron and Campylobacter gracilis, and from postoperative infections, B. thetaiotaomicron was most predominately isolated, followed by B. fragilis, Bacteroides caccae and B. wadsworthia in this order. In this series, we noticed no vancomycin-resistant Gram-positive cocci, nor multidrug-resistant P aeruginosa. There were nine strains of coagulase-negative Staphylococci which show higher MIC against teicoplanin more than 4 gg/mL, but all of them had good susceptibilities against various anti-MRSA antibiotics. We should carefully follow up B. wadsworthia which was resistant to various antibiotics, and also Bacteroides spp. which was resistant to many beta-lactam antibiotics.

[Bacteria isolated from surgical infections and its susceptibilities to antimicrobial agents--special references to bacteria isolated between April 2006 and March 2007].

Tendency of isolated bacteria from infections in abdominal surgery during the period from April 2006 to March 2007 were investigated in a multicenter study in Japan, and the following results were obtained. In this series, 474 strains including 23 strains of Candida spp. were isolated from 170 (75.2%) of 226 patients with surgical infections. Two hundred and twenty-six strains were isolated from primary infections, and 224 strains were isolated from postoperative infections. From primary infections, anaerobic Gram-negative bacteria were predominant, followed by aerobic Gram-negative bacteria, while from postoperative infections aerobic Gram-positive bacteria were predominant, followed by anaerobic Gram-negative bacteria. Among aerobic Gram-positive bacteria, the isolation rate of Staphylococcus spp. was higher from postoperative infections, while Enterococcus spp. was higher from primary infections. Among aerobic Gram-negative bacteria, Escherichia coli was the most predominantly isolated from primary infections, followed by Klebsiella pneumoniae, Enterobacter cloacae and Pseudomonas aeruginosa, in this order, and from postoperative infections, P. aeruginosa was the most predominantly isolated, followed by E. coli and E. cloacae. Among anaerobic Gram-negative bacteria, the isolation rate of Bilophila wadsworthia was the highest from primary infections, followed by Bacteroides fragilis and from postoperative infections, B. fragilis was most predominately isolated, followed by Bacteroides caccae, Bacteroides thetaiotaomicron and B. wadsworthia in this order. In this series, we noticed no methicillin-resistant Staphylococcus aureus, nor multidrug-resistant P. aeruginosa. There were three strains of methicillin-resistant coagulase-negative Staphylococcus aureus, but all of them had good susceptibilities against various anti-MRSA antibiotics. We should carefully follow up B. wadsworthia.

Efficient transformation of small hepatocytes into insulin-expressing cells by forced expression of Pdx1.

BACKGROUND/PURPOSE: The expression of ectopic pancreatic and duodenal homeobox factor 1 (Pdx1) can transform hepatocytes into pancreatic endocrine cells. Small hepatocytes (SHs) have a high possibility to be a cellular source for islet cell transplantation. However, the efficacy of the transformation of SHs into pancreatic endocrine cells is not fully understood. The focus of our study was to compare the efficacy of the transformation into pancreatic endocrine cells of SHs and mature hepatocytes (MHs). METHODS: MHs and SHs were cultured for 3 and 10 days, respectively, before Adeno-Pdx1 gene transduction. Western blot analysis was performed for pancreatic transcription factors, and reverse-transcription polymerase chain reaction (RT-PCR) was performed for the gene expression of pancreatic hormones. Confocal laser microscanning analysis was used to observe insulin and glucagon expression. RESULTS: Although the pancreatic transcription factors Pdx1, Ngn3, NeuroD, and Pax6 were induced in both SHs and MHs after Adeno-Pdx1 gene expression, the pancreatic transcription factors Nkx2.2 and Nkx6.1 were induced in SHs more than in MHs. Glucagon mRNA expression was seen in both SHs and MHs, whereas insulin mRNA expression was higher in SHs than in MHs. Confocal laser microscanning analysis showed that SHs expressed both insulin and glucagon, whereas MHs predominantly expressed glucagon. CONCLUSIONS: SHs were transformed into both insulin-and glucagon-expressing cells, and the efficacy of the transformation into insulin-expressing cells of SHs was higher than that for MHs. Thus, SHs could be a more suitable source of future cell therapy than MHs.

In vitro transformation of adult rat hepatic progenitor cells into pancreatic endocrine hormone-producing cells.

BACKGROUND/PURPOSE: Pancreatic and duodenal homeobox factor 1 (Pdx-1) plays an important role in initiating differentiation toward pancreatic endocrine cells. The transdifferentiation or transformation of hepatocytes into pancreatic endocrine cells could be feasible, due to their similar cellular origins. Our goal in this study was to see if small hepatocytes (SHs) could give rise to pancreatic endocrine cells via exogenous Pdx-1 gene expression. METHODS: SHs were cultured for 10 days before adenovirus (Adt)-mediated Pdx-1 gene transfection. We performed western blot analysis for pancreatic transcription factors in the nuclei and reverse-transcription polymerase chain reaction (RT-PCR) for the gene expression of pancreatic endocrine hormones. Confocal laser microscanning analysis was used to observe the transformation of SHs. RESULTS: Pancreatic transcription factors such as Pdx-1, Ngn3, NeuroD, Nkx2.2, and Pax6 were induced after Adt-Pdx-1 gene transfection. The mRNA expression of pancreatic endocrine hormones (insulin, glucagon, and somatostatin) was induced after the gene transfection. Pdx-1 was expressed in the nucleus, where the cells were positive for one or more of the hormones and cytokeratin (CK) 8. Some cells were positive for multiple hormones. The insulin level increased while the glucagon level decreased after the glucose loading test, depending on the glucose concentration. CONCLUSIONS: SHs are transformed into functional pancreatic endocrine cells after Pdx-1 gene transfection.

Clinical and immunological evaluation of anti-apoptosis protein, survivin-derived peptide vaccine in phase I clinical study for patients with advanced or recurrent breast cancer.

BACKGROUND: We previously reported that survivin-2B, a splicing variant of survivin, was expressed in various types of tumors and that survivin-2B peptide might serve as a potent immunogenic cancer vaccine. The objective of this study was to examine the toxicity of and to clinically and immunologically evaluate survivin-2B peptide in a phase I clinical study for patients with advanced or recurrent breast cancer. METHODS: We set up two protocols. In the first protocol, 10 patients were vaccinated with escalating doses (0.1-1.0 mg) of survivin-2B peptide alone 4 times every 2 weeks. In the second protocol, 4 patients were vaccinated with the peptide at a dose of 1.0 mg mixed with IFA 4 times every 2 weeks. RESULTS: In the first protocol, no adverse events were observed during or after vaccination. In the second protocol, two patients had induration at the injection site. One patient had general malaise (grade 1), and another had general malaise (grade 1) and fever (grade 1). Peptide vaccination was well tolerated in all patients. In the first protocol, tumor marker levels increased in 8 patients, slightly decreased in 1 patient and were within the normal range during this clinical trial in 1 patient. With regard to tumor size, two patients were considered to have stable disease (SD). Immunologically, in 3 of the 10 patients (30%), an increase of the peptide-specific CTL frequency was detected. In the second protocol, an increase of the peptide-specific CTL frequency was detected in all 4 patients (100%), although there were no significant beneficial clinical responses. ELISPOT assay showed peptide-specific IFN-gamma responses in 2 patients in whom the peptide-specific CTL frequency in tetramer staining also was increased in both protocols. CONCLUSION: This phase I clinical study revealed that survivin-2B peptide vaccination was well tolerated. The vaccination with survivin-2B peptide mixed with IFA increased the frequency of peptide-specific CTL more effectively than vaccination with the peptide alone, although neither vaccination could induce efficient clinical responses. Considering the above, the addition of another effectual adjuvant such as a cytokine, heat shock protein, etc. to the vaccination with survivin-2B peptide mixed with IFA might induce improved immunological and clinical responses.

Rapid recovery of postoperative liver function after major hepatectomy using saline-linked electric cautery.

BACKGROUND/AIMS: The exact effect of heat injury in the residual liver on postoperative liver function is not totally understood. The purpose of this study was to compare postoperative liver function after major liver resection using an argon laser beam coagulator (AR) and that using saline-linked electric cautery (SLC) for vessels and bile duct sealing. METHODOLOGY: Between January 2001 and December 2005, thirty patients were analyzed in this study retrospectively. The inclusion criteria were that the patients received hemihepatectomy without vascular and biliary reconstruction in a non-cirrhotic liver. Operative variables and liver functions were compared between the AR method and the SLC method. RESULTS: The clinical profiles of the two groups were almost identical, including preoperative hepatic function. Although there was no difference in most of the intraoperative variables between them, warm ischemic time in the SLC group was shorter than in the AR group (46.53 + 25.42 min vs. 70.47 +/- 11.48 min: p=0.003). Albumin and bilirubin levels at 7 days after hepatectomy were not significantly different between the two groups, but low-density lipoprotein (LDL) and apolipoprotein B (ApoB) levels in the SLC group at 7 days after hepatectomy were significantly higher than in the AR group (84.27 +/- 14.38 mg/dl vs. 60.21 +/- 14.27 mg/dl: p=0.001; 69.53 +/- 17.18 mg/dl vs. 55.87 +/- 9.56 mg/dl: p=0.012, respectively). CONCLUSION: SLC reduces warm ischemic time during hepatectomy. Furthermore, the rapid recovery of LDL and ApoB levels in the SLC group indicates that the SLC method has potential benefits for postoperative hepatic function.

[A case of alveolar hydatid disease of the liver for which progression was seen on CT images].

A 59-year-old woman with autoimmune hepatitis was referred to our hospital for examination of a liver tumor detected in 2001. A CT scan showed a hypovascular mass, and a liver biopsy revealed the presence of an inflammatory pseudotumor. A June 2003 CT scan showed enlargement of the tumor and polycystic pathological changes. Echinococcus antibody was positive, and a diagnosis of liver hydatid disease was made. A liver left lobe resection was performed. CT was useful in this case for detecting change in the lesion and for making the diagnosis of liver hydatid disease.

[Bacteria isolated from surgical infections and its susceptibilities to antimicrobial agents--special references to bacteria isolated between april 2003 and march 2004].

Tendency of isolated bacteria from infections in abdominal surgery during the period from April 2005 to March 2006 were investigated in a multicenter study in Japan, and the following results were obtained. In this series, 384 strains including 18 strains of Candida spp. were isolated from 161 (70.3%) of 229 patients with surgical infections. One hundred and ninty-five strains were isolated from primary infections, and 171 strains were isolated from postoperative infections. From primary infections, aerobic Gram-negative bacteria and aerobic Gram-positive bacteria were predominant, while aerobic Gram-positive bacteria were predominant from postoperative infections. The isolation rate of aerobic Gram-positive bacteria, such as Enterococcus spp. and Staphylococcus aureus were higher from both types of infections. Among anaerobic Gram-positive bacteria, the isolation rate of Peptostreptococcus spp. was the highest from both types of infections. Among aerobic Gram-negative bacteria, Escherichia coli was the most predominantly isolated from primary infections, followed by Pseudomonas aeruginosa, Klebsiella spp. in this order, and from postoperative infections, E. coli was the most predominantly isolated, followed by Klebsiella pneumoniae and P. aeruginosa. Among anaerobic Gram-negative bacteria, the isolation rate of Bacteroides fragilis group was the highest from both primary and postoperative infections. In this series, we noticed no vancomycin-resistant Gram-positive cocci, nor multidrug-resistant P. aeruginosa. But cefazolin-resistant E. coli producing extended spectrum fl-lactamase was seen in 5.0 per cents. We should be carefully followed up the facts that the increasing isolation rates of B. fragilis group and Bilophila wadsworthia which were resistant to both penicillins and cephems.

Current status of surgery for pancreatic cancer.

BACKGROUND: In Japan the annual incidence of pancreatic cancer has increased over the last decade, but no advancement has been made in the long-term prognosis after resection. The significant differences in the surgical procedures between Western countries and Japan have been discussed. Therefore, an adequate comparison and analysis of the data from Japan, Europe and the USA is required. This review evaluates many important published reports from Japan which influence surgical procedure. METHODS: Several important highlights and controversies regarding the concept of surgical treatment and surgical procedure are discussed comparing the results in Japan with those in Western countries. RESULTS: No significant difference in diagnostic strategy using various imaging methods was observed between Japan and Europe. The stage classification for pancreatic cancer by the Japanese Pancreatic Society (JPS) seems to be superior to others, because the results on long-term prognosis after pancreatectomy of cases with pancreatic head cancer, diagnosed as tubular adenocarcinoma, has been arranged logically. Pancreatectomy with extended radical dissection is recommended in Japan, but several clinical studies from Europe and the USA suggest that this is ineffective. The basic concepts of this controversy have recently come closer altogether. Scientific clinical trials for instance on the necessity of adjuvant treatment, etc., are now on-going. CONCLUSION: The characteristics on diagnosis and treatment of pancreatic cancer in Japan are described. The JPS registration system for pancreatic cancer can provide much more information, i.e. dependency on diagnostic methods, highly frequent sites of lymph node and of distant metastases, the prognosis of small pancreatic cancers, etc. The indication for any surgical treatments should be limited to cases with the possibility of cancer free margins.

Anastomotic suture line recurrence of early rectal carcinomas that had been resected by laparoscopic surgery.

We report herein a case of a 64-year-old woman found to have anastomotic suture line recurrence of an early rectal carcinoma. The patient had undergone laparoscopy-assisted low anterior rectal resection for an early rectal carcinoma 2 years before the anastomotic site recurrence. A follow-up colonoscopy revealed an elevated lesion on the anastomotic suture line. The diagnosis of adenocarcinoma was confirmed by biopsy. The patient underwent a resection of the remnant rectum. Histological examination of the resected specimen showed that the anastomotic site recurrence might have been caused by intraluminal implantation from the primary rectal cancer. We speculate that intraluminal implantation might be caused by insufficient intraoperative rectal irrigation because of limited access often encountered in laparoscopic surgery. We propose that it is necessary to devise a method with which to perform sufficient intraoperative rectal irrigation in laparoscopic surgery for rectal carcinoma.

Assessment of nutritional status and prediction of postoperative liver function from serum apolioprotein A-1 levels with hepatectomy.

BACKGROUND: We investigated the usefulness of apolipoprotein A-1 (apoA) as an indicator of nutritional status, and the correlation of the preoperative apoA level with changes in postoperative liver function following hepatectomy. METHODS: One hundred patients underwent hepatectomy. Serum levels of apoA, prealbumin (prealb), retinol-binding protein (RBP), lectin-cholesterol acyltransferase (LCAT), hyarulonate (HA), indocyanine green dye retention at 15 minutes (ICG), and the receptor index of Tc-GSA scintigraphy (LHL15) were measured at preoperation and on postoperative days (POD) 7 and 14. Partial resection was carried out in 62 cases, segmentectomy in nine cases, and bisegmentectomy in 29 cases. Co-existent liver conditions were normal liver (NL) in 43 cases, chronic hepatitis (CH) in 29 cases, and liver cirrhosis (LC) in 28 cases. RESULTS: In most cases the serum apoA level had decreased on POD 7, and recovered on POD 14. There were no significant differences in the changes of apoA between the individual operative procedures. Although preoperative apoA had almost the same value in the NL, CH, and LC cases, apoA in LC cases on POD 14 was the lowest of all cases. The apoA level showed significant correlations with prealb, LCAT, and HA on POD 14. All cases were divided into two groups (group N: apoA over 91 mg/dl; group L: apoA under 90 mg/dl) based on the preoperative serum apoA level. On POD 14, the ICG, LHL15, and HA of group L were significantly deteriorated compared with those of group L. CONCLUSION: The serum level of apoA reflects the changes in hepatic protein synthetic ability after hepatectomy; therefore, it may be possible to estimate recovery of nutritional status after hepatectomy from serum apoA. Moreover, we can predict postoperative deterioration of liver function from the preoperative apoA level.

Assessment of liver fibrosis by a noninvasive method of transient elastography and biochemical markers.

AIM: To assess the correlation between the fibrotic area (FA) as calculated by a digital image analysis (DIA), and to compare the diagnostic accuracy of FibroScan to the other existing Liver fibrosis (LF) markers using the receiver operating curve analysis. METHODS: We recruited 30 patients who underwent a liver resection for three different etiologies including normal liver, hepatitis B, and hepatitis C. Liver stiffness was measured by using a FibroScan. The FA was then calculated by DIA to evaluate LF in order to avoid any sampling bias. RESULTS: The FA negatively correlated with Prothrom-bin time (PT), platelet count, lecithin-cholesterol acyltransferase (LCAT), and pre-albumin (ALB). On the other hand, the findings of FibroScan correlated with similar markers. The FA positively correlated with FibroScan, serum hyaluronate level, and type IV collagen level, and aspartate transaminase to platelet ratio index (APRI). The area under the receiver operating curve for FibroScan was higher than that for the other markers, even though the statistical significance was minimal. CONCLUSION: Our findings suggest that FibroScan can initially be used to assess LF as an alternative to a liver biopsy (LB) and serum diagnosis, because it is a safe method with comparable diagnostic accuracy regarding the existing LF markers.

Intraductal papillary mucinous neoplasms of the pancreas: an analysis of protein expression and clinical features.

BACKGROUND/PURPOSE: The molecular pathology of intraductal papillary mucinous neoplasms (IPMNs) of the pancreas has not been well characterized, and there are no reliable markers to predict the presence of associated invasive carcinoma in patients with IPMNs. We investigated the clinicopathologic characteristics of 37 IPMNs and the immunohistochemical findings of these tumors to investigate the malignancy of IPMNs. METHODS: Between May 1992 and September 2003, 37 patients with IPMNs, 24 with adenoma and 13 with carcinoma, underwent pancreatic resections at Sapporo Medical University Hospital, Japan. In tumor specimens from these patients, we immunohistochemically analyzed the expression of p53 protein, proliferating-cell nuclear antigen (PCNA), vascular endothelial growth factor (VEGF), matrix metalloproteinase-7 (MMP-7), and E-cadherin. Clinical features and follow-up after resection were recorded. RESULTS: Aberrant expression of the proteins examined was frequently observed. Namely, there were significant differences in the expression of MMP-7 according to clinicopathological characteristics. Positive expression of MMP-7 was found in all of nine patients with infiltrating ductal pancreatic adenocarcinoma (IDC) and in all of seven patients with invasive intraductal papillary mucinous adenocarcinoma (IC-IPMC); however, 33.3% of patients with noninvasive IPMA, 58.3% of patients with intraductal papillary mucinous adenoma (IPMA), and all normal pancreatic tissues were negative for MMP-7; differences which were statistically significant (P < 0.05). CONCLUSIONS: Our current results indicate that MMP-7 may play a significant role in the progression of noninvasive to invasive IPMC.

[Bacteria isolated from surgical infections and its susceptibilities to antimicrobial agents--special references to bacteria isolated between April 2003 and March 2004].

Tendency of isolated bacteria from infections in general surgery during the period from April 2004 to March 2005 were investigated in a multicenter study in Japan, and the following results were obtained. In this series, 645 strains including 17 strains of Candida spp. were isolated from 226 (79.0%) of 286 patients with surgical infections. Three hundred and seventeen strains were isolated from primary infections, and 345 strains were isolated from postoperative infections. From primary infections, anaerobic Gram-positive bacteria and anaerobic Gram-negative bacteria were predominant, while aerobic Gram-positive bacteria were predominant from postoperative infections. The isolation rate of aerobic Gram-positive bacteria, such as Enterococcus spp. and Staphylococcus aureus were higher from both types of infections. Among anaerobic Gram-positive bacteria, the isolation rate of Peptostreptococcus spp. was the highest from both types of infections. Among aerobic Gram-negative bacteria, Escherichia coli was the most predominantly isolated from primary infections, followed by Pseudomonas aeruginosa, Klebsiella pneumoniae and Citrobacter freundii in this order, and from postoperative infections, P. aeruginosa was the most predominantly isolated, followed by E. coli, E. cloacae, and K. pneumoniae. Among anaerobic Gram-negative bacteria, the isolation rate of Bacteroides fragilis group was the highest from both primary infections followed by Bilophila wadsworthia. While the isolation rate of B. fragilis group was also the highest from postoperative infections, the following bacteria were Bacteroides thetaiotaomicron and B. wadsworthia in this order. In this series, we noticed no vancomycin-resistant Gram-positive cocci, but a few strains of moderately arbekacin-resistant MRSA. Carbapenem-resistant P. aeruginosa but not multidrug-resistant was seen in 13.3 per cents. Also cefazolin-resistant E. coli probably producing extended spectrum beta-lactamase was seen in 7.0 per cents. We should be carefully followed up the facts that an increasing isolation rates of B. fragilis group and B. wadsworthia which were resistant to both penicillins and cephems.

In situ graft-trimming method using polyester vascular prosthesis for inferior vena cava reconstruction after hepatectomy.

Hepatectomy for secondary liver cancer that has invaded the inferior vena cava (IVC) can be the only way to achieve long-term survival. We describe a method for hepatectomy combined with partial IVC resection without venous bypass circulation and an in situ graft-trimming method to avoid graft size mismatch after reconstruction. We carried out left hepatectomy extended to segment 1 with partial IVC resection first. During resection and reconstruction of the IVC, it was clamped below the right hepatic vein and above the inferior right hepatic vein to maintain systemic circulation. The graft was trimmed in situ, after a half running suture of the graft was finished to ensure the correct size. Preservation of both inferior right hepatic vein and right hepatic vein helps to maintain systemic circulation during reconstruction of the IVC. The in situ graft-trimming method is an easy and safe method to ensure the correct graft size after IVC reconstruction.

Liver repopulation and long-term function of rat small hepatocyte transplantation as an alternative cell source for hepatocyte transplantation.

Hepatocyte transplantation (HT) is an attractive therapeutic modality for liver disease as an alternative for liver organ transplantation. Primary fresh hepatocytes (FHs) are the exclusive cell source that has been used for clinical HT. However, the use of FHs is limited due to a shortage of donor cells. Small hepatocytes (SHs) are hepatic progenitor cells and can be isolated not only from rodents but also from humans. SHs can proliferate in vitro and express liver functions, although conventional hepatocytes lose them within a short period after culture. SH functions in vivo have never been studied. We therefore investigated HT using SHs to evaluate cell engraftment and function compared to HT using FHs. The donor cell number in the SH group was smaller than that in the FH group at HT. The cell engraftment in the SH group was smaller in the liver and larger in the spleen than in the FH group. The cell engraftment in the liver increased after HT; however, that in the spleen decreased after HT in both groups. HT using SHs supported the serum albumin level in the NAR experiment as well as that using FH, and albumin mRNA was detectable in the recipients' tissues at 12 weeks after HT. In conclusion, HT using SHs showed hepatic repopulation similar to that using FHs. This suggests that both SHs and FHs can repopulate the liver as if they were hepatic stem cells. In addition, HT using SHs supported liver functions such as albumin correction at the same level as that using FHs. These observations strongly support the idea that SHs could be an alternative to primary FHs as a novel cell source for future HT.

Hepatocyte transplantation for total liver repopulation.

Hepatocyte transplantation (HT) is an attractive therapeutic alternative to liver transplantation. A number of experiments have shown the feasibility of total liver parenchymal cell replacement by transplanted hepatocytes. In this review, we would like to highlight researches and clinical reports of HT for liver repopulation. Cellular source of clinical HT should be safety. Immortalized cells, hepatic stem cells, and other stem cells have been used for an experimental model for HT. The exact mechanism of the cell engraftment after HT has not been completely understood, although there were some markers to detect and investigate transplanted cells. In order to achieve liver repopulation following HT, a mild hepatic damage may need to facilitate cell engraftment and replace the host liver by transplanted cells. Hormonal factor may use for the same purpose. Despite the results of preclinical studies promising clinical benefits for cell therapy, the clinical experience of HT has been disappointing, except in a few cases. HT may become an alternative for liver transplantation in the future; however, many efforts should made before establishing an effective method for HT and liver replacement therapy.

Biliary tract malignancy and chronic inflammation from the perspective of pancreaticobiliary maljunction.

This is a brief review of pancreaticobiliary maljunction. The basic treatment for this condition includes either cholecystectomy or extrahepatic bile duct resection. When the condition is accompanied by malignancies, a radical operation should be the first treatment option. Knowledge on molecular pathogenesis is gradually increasing. However, studies should be expanded to include larger patient cohorts, and other types of molecules should be carefully investigated and analyzed.