The Association between Wearing a Mask and COVID-19.

With the widespread and increasing number of cases of Coronavirus Disease (2019) globally, countries have been taking preventive measures against this pandemic. However, there is no universal agreement across cultures on whether wearing face masks are an effective physical intervention against disease transmission. We investigated the relationship between mask wearing and COVID-19 among close contacts of COVID-19 patients in the Hiroshima Prefecture, Japan. In the Hiroshima Prefecture, a COVID-19 form adapted from the reporting form, "Japanese Surveillance in Post-Extreme Emergencies and Disasters", was developed to collect data from COVID-19 patients' close contacts under active epidemiological surveillance at Public Health Centers. The relative risk of COVID-19 for mask users versus non-mask users was calculated. A total of 820 interviewees were included in the analysis and 53.3% of them responded that they wore masks. Non-mask users were infected at a rate of 16.4%, while mask users were infected at a rate of 7.1%. Those who wore masks were infected at a rate of 0.4 times that of those who did not wear masks. (RR = 0.4, 95%CI = 0.3-0.6; Adjusted RR = 0.6, 95%CI = 0.3-0.9). These findings implied that COVID-19 could be avoided to a certain degree by wearing a mask.

A randomized phase III study of hepatic arterial infusion chemotherapy with 5-fluorouracil and subsequent systemic chemotherapy versus systemic chemotherapy alone for colorectal cancer patients with curatively resected liver metastases (Japanese Foundation for Multidisciplinary Treatment of Cancer 32).

AIM: This randomized phase III trial compared hepatic arterial infusion (HAI) chemotherapy with 5-fluorouracil (5-FU) followed by uracil/tegafur (UFT) and leucovorin (LV) versus UFT/LV alone for patients with curatively resected liver metastases from colorectal cancer (CRC). METHODS: The study was designed to include 280 patients to be randomized to receive either HAI with 5-FU followed by UFT/LV (Arm A) or UFT/LV alone (Arm B) to assess whether HAI chemotherapy improved disease-free survival (DFS). RESULTS: Forty-four patients were randomized. Three-year DFS was relatively worse in the experimental arm although this difference was not statistically significant (43.5% in Arm A vs. 58% in Arm B; hazard ratio [HR], 1.304; P = 0.534). The experimental arm also tended to have a worse 3-year overall survival rate (80.2% in Arm A vs. 85.2% in Arm B; HR, 2.255; P = 0.192). There was no significant difference in the frequency of Grade 3 or higher toxicities between the two arms. CONCLUSION: Although this study was limited by a small sample size after early study termination, our analysis found that HAI with 5-FU followed by UFT/LV did not improve the DFS of patients with curatively resected liver metastases from CRC compared with UFT/LV alone. The future studies are necessary to evaluate the survival benefit of HAI in combination with newer systemic chemotherapeutic agents for patients with resectable liver metastases from CRC.

Morphological and microarray analyses of human hepatocytes from xenogeneic host livers.

We previously produced mice with human hepatocyte (h-hep) chimeric livers by transplanting h-heps into albumin enhancer/promoter-driven urokinase-type plasminogen activator-transgenic severe combined immunodeficient (SCID) mice with liver disease. The chimeric livers were constructed with h-heps, mouse hepatocytes, and mouse hepatic sinusoidal cells (m-HSCs). Here, we investigated the morphological features of the chimeric livers and the h-hep gene expression profiles in the xenogeneic animal body. To do so, we performed immunohistochemistry, morphometric analyses, and electron microscopic observations on chimeric mouse livers, and used microarray analyses to compare gene expression patterns in hepatocytes derived from chimeric mouse hepatocytes (c-heps) and h-heps. Morphometric analysis revealed that the ratio of hepatocytes to m-HSCs in the chimeric mouse livers were twofold higher than those in the SCID mouse livers, corresponding to twin-cell plates in the chimeric mouse liver. The h-heps in the chimeric mouse did not show hypoxia even in the twin-cell plate structure, probably because of low oxygen consumption by the h-heps relative to the mouse hepatocytes (m-heps). Immunohistochemical and electron microscopic examinations revealed that the sinusoids in the chimeric mouse livers were normally constructed with h-heps and m-HSCs. However, a number of microvilli projected into the intercellular clefts on the lateral aspects of the hepatocytes, features typical of a growth phase. Microarray profiles indicated that ∼82% of 16 605 probes were within a twofold range difference between h-heps and c-heps. Cluster and principal component analyses showed that the gene expression patterns of c-heps were extremely similar to those of h-heps. In conclusion, the chimeric mouse livers were normally reconstructed with h-heps and m-HSCs, and expressed most human genes at levels similar to those in human livers, although the chimeric livers showed morphological characteristics typical of growth.

Steroid-free living donor liver transplantation for HCV--a multicenter prospective cohort study in Japan.

This prospective, non-randomized, multicenter cohort study analyzed the safety and efficacy of a steroid-free immunosuppressive (IS) protocol for hepatitis C virus (HCV)-positive living donor liver transplant (LDLT) recipients in Japan. Of 68 patients enrolled from 13 transplant centers, 56 fulfilled the inclusion/exclusion criteria; 27 were assigned the steroid-free IS protocol (Fr group) and 29 the traditional steroid-containing IS protocol (St group). Serum HCV RNA levels increased over time and were higher in the St group until postoperative day 90 (POD 14, p=0.013). Preemptive anti-HCV therapy was started in a higher percentage of recipients (59.3%) in the Fr group than in the St group (31.0%, p=0.031), mainly due to early HCV recurrence. The incidence of HCV recurrence at one yr was lower in the Fr group (22.2%) than in the St group (41.4%; p=0.066). The incidence of acute cellular rejection was similar between groups. New onset diabetes after transplant, cytomegalovirus infection, and renal dysfunction were significantly less frequent in the Fr group than in the St group (p=0.022, p<0.0001, p=0.012, respectively). The steroid-free IS protocol safely reduced postoperative morbidity and effectively suppressed both the HCV viral load in the early post-transplant period and HCV recurrence in HCV-positive LDLT recipients.

Treatment strategy for early hepatocellular carcinomas: comparison of radiofrequency ablation with or without transcatheter arterial chemoembolization and surgical resection.

BACKGROUND: The preferred choice between surgical treatment and radiofrequency ablation (RFA) for the treatment of small resectable hepatocellular [corrected] carcinoma (HCC) has become a subject for debate. METHODS: We compared the results of hepatic resection (n = 199) with those of RFA (n = 87), of which 69 patients were treated with transcatheter arterial chemoembolization followed by RFA, for 286 patients with 3 or fewer nodules, none of which exceeded 3 cm in diameter at Hiroshima University Hospital. RESULTS: In subgroup analysis of single HCC with tumor size exceeding 2 cm in Child-Pugh class A, the disease-free survival time was significantly longer in the surgical resection group than in the RFA group (P = 0.048). In the subgroups of a single and multiple HCC with tumor size ≤2 cm in Child-Pugh class A, the overall and disease-free survival rates were almost the same for the surgical resection and RFA groups (P = 0.46 and 0.58, respectively, in single HCC, and P = 0.98 and 0.98, respectively, in multiple HCC). CONCLUSION: Surgical resection may provide better long-term disease-free survival than RFA in the subgroup of a single HCC exceeding 2 cm of Child-Pugh class A.

Significance of platelet count in the outcomes of hepatectomized patients with hepatocellular carcinoma exceeding the Milan criteria.

BACKGROUND: The appropriate treatment strategy for advanced hepatocellular carcinoma (HCC) that does not meet the Milan criteria (MC) is unclear. The aim of this study was to determine the significance of surgical treatment for such patients. STUDY DESIGN: From January 1990 to December 2007, 151 patients with HCC exceeding MC who underwent curative surgical treatment were enrolled. Survival and recurrence data and clinicopathological factors were examined. Prognostic factors were analyzed to identify those that contributed to improved surgical outcomes retrospectively. RESULTS: After the initial hepatectomy, the overall 3-, 5-, and 10-year survival rates were 73%, 55%, and 33%, respectively, for the 151 patients in this study; the corresponding disease-free survival rates were 36%, 30%, and 17%, respectively. A platelet count under 10(5)/mm(3), multiple tumors, and liver cirrhosis of noncancerous tissue were adverse survival and disease-free survival factors by univariate analysis. Platelet count was an independent prognostic factor by multivariate analysis. The 3-, 5-, and 10-year overall survival rates of HCC exceeding MC in patients whose platelet count was 10(5)/mm(3) or greater reached 76%, 65%, and 44%, respectively, and were comparable with those that met MC (86%, 68%, and 37%, respectively). CONCLUSIONS: Hepatectomy for patients with advanced HCC exceeding MC improves survival, especially for patients with a sufficiently high platelet count, although recurrence rates after initial hepatectomy are high.

Relationship between the cAMP levels in leukocytes and the cytokine balance in patients surviving gram negative bacterial pneumonia.

Lipopolysaccharide-stimulated leukocytes secrete proinflammatory cytokines including tumor necrosis factor-α and interleukin-12. Over-activation of host defense systems may result in severe tissue damage and requires regulation. Granulocyte colony-stimulating factor and interleukin-10 are candidate cytokines for inducing tolerance to lipopolysaccharide re-stimulation. We compared cytokines secreted by lipopolysaccharide-stimulated blood cells from patients who had survived gram negative bacterial pneumonia (Pseudomonas aeruginosa, Escherichia coli or Proteus mirabilis, n = 26) and age-matched healthy volunteers (n = 18). Interleukin-12p70 and tumor necrosis factor-α expression was significantly lower in patients (p = 0.0039 and p<0.001) compared to healthy controls, while granulocyte colony-stimulating factor production was markedly higher in patients (p<0.001). Levels of interleukin-10 were comparable. Granulocyte colony-stimulating factor expression was inversely correlated with interleukin-12p70 (R = -0.71, p<0.001) and tumor necrosis factor-α (R = -0.64, p<0.001) expression; interleukin-10 showed no significant correlation. In unstimulated leukocytes from patients, cAMP levels were significantly raised (p = 0.020) and were correlated inversely with interleukin-12p70 levels (R = -0.81, p<0.001) and directly with granulocyte colony-stimulating factor (R = 0.72, p = 0.0020), matrix metalloproteinase-9 (R = 0.67, p = 0.0067) and interleukin-10 (R = 0.54, p = 0.039) levels. Our results demonstrate that granulocyte colony-stimulating factor production by lipopolysaccharide-stimulated leukocytes is a useful indicator of tolerance induction in surviving pneumonia patients and that measuring cAMP in freshly isolated leukocytes may also be clinically significant.

Therapeutic potential of propagated hepatocyte transplantation in liver failure.

BACKGROUND: This study aimed to evaluate the therapeutic potential of intrasplenic transplantation of culture-propagated homologous hepatocytes in rats suffering from acute liver failure (ALF). METHODS: ALF was induced in dipeptidyl peptidase IV-negative (DPPIV(-)) Fischer 344 rats by totally removing the two anterior liver lobes (68% of the liver) and ligating the pedicle of the right lobe (24% of the liver). Hepatocytes isolated from DPPIV(+) Fischer 344 rats were cultured for 11 d to propagate 3-fold, and the resulting hepatocytes were dubbed "culture-propagated hepatocytes (CPHEPs)". A total of 1.5 × 10(7) cells of CPHEPs were transplanted intrasplenically before ALF induction (CPHEP group). Similarly, freshly isolated hepatocytes (FIHEPs) were transplanted as a positive control (FIHEP group), and culture medium (CM) was injected into rats as a negative control (CM group). RESULTS: The survival of the CPHEP group was comparable to that of the FIHEP group and longer than that of the CM group (P < 0.01). Both CPHEP and FIHEP transplantation improved blood parameters such as ammonia, total bilirubin, glutamic pyruvic transaminase, and glutamic oxaloacetic transaminase; transplantation also affected liver tissue parameters such as apoptosis rate and bromodeoxyuridine-labeling index. CONCLUSIONS: Transplantation of culture-propagated homologous hepatocytes has a remarkable therapeutic potential for ALF in rats.

Growth hormone-dependent pathogenesis of human hepatic steatosis in a novel mouse model bearing a human hepatocyte-repopulated liver.

Clinical studies have shown a close association between nonalcoholic fatty liver disease and adult-onset GH deficiency, but the relevant molecular mechanisms are still unclear. No mouse model has been suitable to study the etiological relationship of human nonalcoholic fatty liver disease and human adult-onset GH deficiency under conditions similar to the human liver in vivo. We generated human (h-)hepatocyte chimeric mice with livers that were predominantly repopulated with h-hepatocytes in a h-GH-deficient state. The chimeric mouse liver was mostly repopulated with h-hepatocytes about 50 d after transplantation and spontaneously became fatty in the h-hepatocyte regions after about 70 d. Infusion of the chimeric mouse with h-GH drastically decreased steatosis, showing the direct cause of h-GH deficiency in the generation of hepatic steatosis. Using microarray profiles aided by real-time quantitative RT-PCR, comparison between h-hepatocytes from h-GH-untreated and -treated mice identified 14 GH-up-regulated and four GH-down-regulated genes, including IGF-I, SOCS2, NNMT, IGFLS, P4AH1, SLC16A1, SRD5A1, FADS1, and AKR1B10, respectively. These GH-up- and -down-regulated genes were expressed in the chimeric mouse liver at lower and higher levels than in human livers, respectively. Treatment of the chimeric mice with h-GH ameliorated their altered expression. h-Hepatocytes were separated from chimeric mouse livers for testing in vitro effects of h-GH or h-IGF-I on gene expression, and results showed that GH directly regulated the expression of IGF-I, SOCS2, NNMT, IGFALS, P4AH1, FADS1, and AKR1B10. In conclusion, the chimeric mouse is a novel h-GH-deficient animal model for studying in vivo h-GH-dependent human liver dysfunctions.

In vitro evaluation of cytochrome P450 and glucuronidation activities in hepatocytes isolated from liver-humanized mice.

Cryopreserved human (h-) hepatocytes are currently regarded as the best in vitro model for predicting human intrinsic clearance of xenobiotics. Although fresh h-hepatocytes have greater plating efficiency on dishes and greater metabolic activities than cryopreserved cells, performing reproducible studies using fresh hepatocytes from the same donor and having an "on demand" supply of fresh hepatocytes are not possible. In this study, cryopreserved h-hepatocytes were transplanted into albumin enhancer/promoter-driven, urokinase-type plasminogen activator, transgenic/severe combined immunodeficient (uPA/SCID) mice to produce chimeric mice, the livers of which were largely replaced with h-hepatocytes. We determined whether the chimeric mouse could serve as a novel source of fresh h-hepatocytes for in vitro studies. h-Hepatocytes were isolated from chimeric mice (chimeric hepatocytes), and cytochrome P450 (P450) activities were determined. Compared with cryopreserved cells, the P450 (1A2, 2C9, 2C19, 2D6, 2E1, 3A) activities of fresh chimeric hepatocytes were similar or greater. Moreover, ketoprofen was more actively metabolized through glucuronide conjugates by fresh chimeric hepatocytes than by cryopreserved cells. We conclude that chimeric mice may be a useful tool for supplying fresh h-hepatocytes on demand that provide high and stable phase I enzyme and glucuronidation activities.

Hepatic hyperplasia associated with discordant xenogeneic parenchymal-nonparenchymal interactions in human hepatocyte-repopulated mice.

Liver mass is optimized in relation to body mass. Rat (r) and human (h) hepatocytes were transplanted into liver-injured immunodeficient mice and allowed to proliferate for 3 or 11 weeks, respectively, when the transplants stopped proliferating. Liver/body weight ratio was normal throughout in r-hepatocyte-bearing mice (r-hep-mice), but increased continuously in h-hepatocyte-bearing mice (h-hep-mice), until reaching approximately three times the normal m-liver size, which was considered to be hyperplasia of h-hepatocytes because there were no significant differences in cell size among host (mouse [m-]) and donor (r- and h-) hepatocytes. Transforming growth factor-beta (TGF-beta) type I receptor, TGF-beta type II receptor, and activin A type IIA receptor mRNAs in proliferating r-hepatocytes of r-hep-mice were lower than in resting r-hepatocytes (normal levels) and increased to normal levels during the termination phase. Concomitantly, m-hepatic stellate cells began to express TGF-beta proteins. In stark contrast, TGF-beta type II receptor and activin A type IIA receptor mRNAs in h-hepatocytes remained low throughout and m-hepatic stellate cells did not express TGF-beta in h-hep-mice. As expected, Smad2 and 3 translocated into nuclei in r-hep-mice but not in h-hep-mice. Histological analysis showed a paucity of m-stellate cells in h-hepatocyte colonies of h-hep-mouse liver. We conclude that m-stellate cells are able to normally interact with concordant r-hepatocytes but not with discordant h-hepatocytes, which seems to be at least partly responsible for the failure of the liver size optimization in h-hep-mice.

Comparison of immunohistochemistry assays and real-time reverse transcription-polymerase chain reaction for analyzing hormone receptor status in human breast carcinoma.

The estrogen receptor (ER) and progesterone receptor (PgR) status of 163 surgical breast cancer specimens determined on real-time quantitative reverse transcription-polymerase chain reaction (RT-PCR) using frozen tumor tissue were compared with that determined using three automated immunohistochemistry (IHC) assays including Dako (Glostrup, Denmark), Ventana (Tucson, AZ, USA) and BioGenex (San Ramon, CA, USA) assay. All specimens were semiquantified according to the Allred score and J-score. The cut-offs for ER determined by log (ER/glyceraldehyde-3-phosphate dehydrogenase (GAPDH)) were -3.6 and -3.2 based on the Allred score and J-score, respectively, and those for PgR determined by log (PgR/GAPDH) were -3.2 and -2.8, respectively. The Allred total score (TS) and the J-score for ER and PgR on IHC were significantly correlated with the result on RT-PCR (P < 0.00001). There was a high degree of concordance among ER and PgR status on IHC and those on RT-PCR, suggesting that RT-PCR is a useful method for evaluation of ER and PgR status. Some discrepancies between the IHC and RT-PCR results were identified, however. Accordingly, further studies of RT-PCR assays for hormone receptor (HR) are necessary with regard to biological behavior and responsiveness to hormone therapy.

A new technique for reconstruction of the middle hepatic vein without graft interposition: "the digging technique".

Ill-located liver metastases close to the cavo-hepatic confluence often require resection and reconstruction of hepatic veins. However, most of the current techniques for reconstruction of the hepatic veins require graft interposition or complex venoplasty. The present case report describes a new surgical procedure which allows reconstructing the middle hepatic vein (MHV) by direct end-to-end anastomosis after a right hepatectomy for colorectal liver metastases invading the right and middle hepatic veins. This technique is called the "digging technique", in which an additional atypical resection of a part of segment 4a "digging" around the distal end of the MHV in order to further mobilize the liver and to achieve, with an upward lifting of the remnant liver, a tension-free end-to-end reconstruction of the MHV. The immediate postoperative course was uneventful. After 6 months of follow-up the patient was well and the MHV was patent. In selected patients with liver metastases close to the MHV-inferior vena cava confluence, requiring a right hepatectomy, the "digging technique" allows a safe direct end-to-end anastomosis avoiding graft interposition.

Suppression of hepatocellular carcinoma recurrence after rat liver transplantation by FTY720, a sphingosine-1-phosphate analog.

BACKGROUND.: Although the outcome of liver transplant patients with hepatocellular carcinoma (HCC) has improved with the introduction of strict criteria, tumor recurrence still remains a significant problem. Sphingosine-1-phosphate (S1P) is a phospholipid mediator that can induce diverse cellular responses, such as proliferation, migration, adhesion, and cell-rounding, in cancer cells. We investigated whether FTY720, a S1P analog, suppresses tumor recurrence after experimental liver transplantation in a rat HCC model. METHODS.: HCC-bearing rats were subjected to orthotropic liver transplantation. HCC cells were analyzed for cell migration, proliferation, and S1P receptors. RESULTS.: FTY720 induced the down-regulation of the S1P-1 receptor of HCC cells and suppressed both cancer cell migration and proliferation. FTY720 also suppressed mitogen-activated protein kinase phosphorylation. The suppression of tumor recurrence after liver transplantation and a significant prolongation of survival were observed in the FTY720-treated rats, in comparison with FTY720-untreated rats. CONCLUSION.: FTY720 suppresses the invasiveness and proliferation of HCC through a down-regulating S1P-1 receptor to suppress the recurrence of HCC after liver transplantation; FTY720 may be used as a new antimetastatic agent for the prevention of tumor recurrence after liver transplantation.

Adoptive immunotherapy with liver allograft-derived lymphocytes induces anti-HCV activity after liver transplantation in humans and humanized mice.

After liver transplantation in HCV-infected patients, the virus load inevitably exceeds pre-transplantation levels. This phenomenon reflects suppression of the host-effector immune responses that control HCV replication by the immunosuppressive drugs used to prevent rejection of the transplanted liver. Here, we describe an adoptive immunotherapy approach, using lymphocytes extracted from liver allograft perfusate (termed herein liver allograft-derived lymphocytes), which includes an abundance of NK/NKT cells that mounted an anti-HCV response in HCV-infected liver transplantation recipients, despite the immunosuppressive environment. This therapy involved intravenously injecting patients 3 days after liver transplantation with liver allograft-derived lymphocytes treated with IL-2 and the CD3-specific mAb OKT3. During the first month after liver transplantation, the HCV RNA titers in the sera of recipients who received immunotherapy were markedly lower than those in the sera of recipients who did not receive immunotherapy. We further explored these observations in human hepatocyte-chimeric mice, in which mouse hepatocytes were replaced by human hepatocytes. These mice unfailingly developed HCV infections after inoculation with HCV-infected human serum. However, injection of human liver-derived lymphocytes treated with IL-2/OKT3 completely prevented HCV infection. Furthermore, an in vitro study using genomic HCV replicon-containing hepatic cells revealed that IFN-gamma-secreting cells played a pivotal role in such anti-HCV responses. Thus, our study presents what we believe to be a novel paradigm for the inhibition of HCV replication in HCV-infected liver transplantation recipients.

Hepatocytes from fibrotic liver possess high growth potential in vivo.

Hepatocyte transplantation is effective for treating liver failure, but healthy donors as a source of hepatocytes are quite limited. The livers of patients with hepatic fibrosis could be an alternative source; however, few reports have examined the nature of hepatocytes from fibrotic livers (f-hepatocytes). In this study, we compared the growth of f-hepatocytes and hepatocytes from normal livers (n-hepatocytes). Hepatocytes were isolated from normal and CCl(4)-treated wild-type Fischer rats that express dipeptidyl dipeptidase IV (DPPIV) gene (DPPIV(+)). The n- and f-hepatocytes proliferated in culture at similar rates. Both types of hepatocytes were transplanted into DPPIV(-) mutant Fischer rats that had been treated with retrorsine to injure the liver and were partially hepatectomized (PHx) before transplantation. Both n- and f-DPPIV(+)-hepatocytes proliferated and formed colonies. The colony sizes of f-hepatocytes 21 days posttransplantation were approximately three times those of n-hepatocytes. The hepatocytes were analyzed using a fluorescence activated cell sorter (FACS). The FACS profile differed between f- and n-hepatocytes: f-hepatocytes were less granular, less autofluorescent, and smaller than n-hepatocytes. These characteristics of f-hepatocytes resembled those reported for small-sized n-hepatocytes (SHs), which are highly proliferative and preferentially express a unique set of 10 SH genes. However, f-hepatocytes preferentially expressed only five of the SH genes. The expression profile of f-hepatocytes was rather similar to that of proliferating n-hepatocytes in the regenerating liver after PHx. The f-hepatocytes were morphologically normal and did not show any preneoplastic phenotype. These normal and proliferative natures of f-hepatocytes in vivo suggest the fibrotic liver as a source of hepatocytes for transplantation.

Successful hepatitis B vaccination in liver transplant recipients with donor-specific hyporesponsiveness.

Currently, patients are prescribed lifelong treatment with hepatitis B immunoglobulin (HBIg) after liver transplantation (LT) for hepatitis B virus (HBV)-related diseases in order to prevent reinfection with HBV. Active immunization with an HBV vaccine would be a preferable alternative; however, the immunosuppressive environment in LT recipients is believed to elicit a poor response to vaccination. Minimizing the exposure of the HBV-infected LT recipients to immunosuppressants would be beneficial in inducing adaptive immunity against HBV by vaccination. In this study, in addition to efforts to minimize immunosuppression, prophylaxis with HBV vaccination combined with continuous HBIg administration was performed in 17 LT recipients who had undergone transplantation attributable to HBV-related diseases. During the observation period, the overall response rate to HBV vaccination was 64.7%. The immune status of the recipients was evaluated by a mixed lymphocyte reaction assay in response to allostimulation. Patients showing a donor-specific hyporesponse with a well-maintained response to the third-party stimulus always achieved a sustained immune response to the vaccine, whereas patients showing a hyporesponse to both the donor and the third-party stimulus were unable to do so. Thus, inducing an anti-donor-specific immunosuppressive status by minimizing immunosuppression should enable post-transplant HBV vaccination to be a promising prophylactic strategy.

Significant correlation between spleen volume and thrombocytopenia in liver transplant patients: a concept for predicting persistent thrombocytopenia.

Interferon (IFN) therapy with or without ribavirin treatment is well established as a standard antiviral treatment for hepatitis C virus (HCV)-infected patients. However, susceptibility to thrombocytopenia is a major obstacle for initiating or continuing this therapy, particularly in liver transplant (LTx) recipients with HCV. Studies have reported that splenectomy performed concurrently with LTx is a feasible strategy for conditioning patients for anti-HCV IFN therapy. However, the relationship between the severity of splenomegaly and alterations in the blood cytopenia in LTx recipients remains to be clarified. Here, we analyzed the relationship between spleen volume (SV) and thrombocytopenia in 45 patients who underwent LTx at Hiroshima University Hospital. The extent of pre-LTx splenomegaly [the SV to body surface area (BSA) ratio in an individual] was inversely correlated with both the post-LTx white blood cell count and platelet (PLT) count (P < 0.001). Furthermore, the PLT count of patients with thrombocytopenia (PLT count or= 400), persistent thrombocytopenia is predictable after LTx.

Synthetic bioabsorbable stent material for duct-to-duct biliary reconstruction.

Biliary stricture remains a significant cause of morbidity after liver transplantation. We performed duct-to-duct biliary anastomosis by using an absorbable stent tube with a diameter equal to that of pig common bile duct as an internal stent. The stent tube was constructed using a synthetic biodegradable material-a lactic glycolic acid and epsilon-caprolactone copolymer. Three pigs were alive without cholestasis for 180 d; however, 1 pig died on the 65th postoperative d, and autopsy revealed no cholestasis or biliary sledge in the biliary stent tube. The 3 pigs were euthanized for histological examinations 180 d after surgery; the biliary stent tube was completely absorbed by this time. These experimental results showed the good patency of the absorbable biliary stent tube. In the future, the absorbable biliary stent tube is expected to be clinically developed as a biliary stent for biliary anastomosis, which may protect the biliary anastomotic stricture.

Hepatectomy for hepatocellular carcinoma in elderly patients aged 75 years or more.

BACKGROUND: The aim of this study was to clarify the characteristics of elderly hepatocellular carcinoma (HCC) patients aged 75 years or more who underwent hepatectomy and to clarify whether elderly patients with HCC benefit from hepatectomy. METHODS: Between January 1990 and December 2006, 570 patients underwent curative hepatectomy for HCC. Elderly patients were defined as those aged 75 years or more. Clinicopathological data and outcomes after hepatectomy for 64 elderly and 502 younger patients were prospectively collected and compared. RESULTS: The proportion of elderly patients with chronic viral infection was less than that of younger patients (p < 0.001). Cirrhotic patients in the elderly group were less than those in the younger group (p = 0.03). The elderly patients had better liver function than did the younger patients (p = 0.007) but had more advanced HCC with microscopic vascular invasion than did the younger patients (p = 0.04). There was no operative mortality in the elderly patients and there was no significant difference in postoperative complication rates and long-term survival after hepatectomy between the two groups. CONCLUSIONS: Hepatectomy for elderly patients with resectable HCC is safe and feasible. Selected elderly patients with HCC might benefit from hepatectomy.