Impact of group work on the hidden curriculum that induces students' unprofessional behavior toward faculty.

BACKGROUND: Hidden curriculum (HC) can limit the effects of professionalism education. However, the research on how HC triggers unprofessional behavior among medical students is scant. Furthermore, there is no established approach for how faculty members may create a context, such as an educational environment and education system, that prevents students' unprofessional behavior. This study aimed to develop an educational approach to prevent unprofessional behavior and clarify how faculty members consider HC that triggers students' unprofessional behavior. METHODS: The study sample comprised 44 faculty members and eight medical students from the Chiba University School of Medicine. The participants were divided into groups and asked the following question: "What attitudes, statements, and behaviors of senior students, physicians, and faculty members trigger medical students' unprofessional behavior?" The responses were collected using the affinity diagram method. The group members discussed the causes and countermeasures for the selected attitudes, statements, and behaviors of senior students, physicians, and faculty members based on the affinity diagram. The impact of the group work on the faculty members was surveyed using questionnaires immediately after its completion and six months later. Furthermore, the cards in the group work were analyzed using content analysis. RESULTS: The responses to the questionnaire on group work indicated that some faculty members (43.8%) improved HC, while others suggested conducting group work with more participants. The content analysis revealed six categories - inappropriate attitude/behavior, behavior encouraging unprofessional behavior, lack of compliance with regulations, harassment of other medical staff, inappropriate educational environment/supervisor, and inappropriate self-control - and 46 subcategories. CONCLUSIONS: The HC that triggers students' unprofessional behavior includes the words and actions of the educator, organizational culture, and educational environment. Group work makes faculty members aware of the HC that triggers unprofessional behavior, and induces behavioral change for HC improvement in the educational activities. Educators should refrain from using words and actions that encourage unprofessional behavior, such as personal anecdotes, as they reduce students' learning motivation.

Developing Medical Education Curriculum Reform Strategies to Address the Impact of Generative AI: Qualitative Study.

BACKGROUND: Generative artificial intelligence (GAI), represented by large language models, have the potential to transform health care and medical education. In particular, GAI's impact on higher education has the potential to change students' learning experience as well as faculty's teaching. However, concerns have been raised about ethical consideration and decreased reliability of the existing examinations. Furthermore, in medical education, curriculum reform is required to adapt to the revolutionary changes brought about by the integration of GAI into medical practice and research. OBJECTIVE: This study analyzes the impact of GAI on medical education curricula and explores strategies for adaptation. METHODS: The study was conducted in the context of faculty development at a medical school in Japan. A workshop involving faculty and students was organized, and participants were divided into groups to address two research questions: (1) How does GAI affect undergraduate medical education curricula? and (2) How should medical school curricula be reformed to address the impact of GAI? The strength, weakness, opportunity, and threat (SWOT) framework was used, and cross-SWOT matrix analysis was used to devise strategies. Further, 4 researchers conducted content analysis on the data generated during the workshop discussions. RESULTS: The data were collected from 8 groups comprising 55 participants. Further, 5 themes about the impact of GAI on medical education curricula emerged: improvement of teaching and learning, improved access to information, inhibition of existing learning processes, problems in GAI, and changes in physicians' professionality. Positive impacts included enhanced teaching and learning efficiency and improved access to information, whereas negative impacts included concerns about reduced independent thinking and the adaptability of existing assessment methods. Further, GAI was perceived to change the nature of physicians' expertise. Three themes emerged from the cross-SWOT analysis for curriculum reform: (1) learning about GAI, (2) learning with GAI, and (3) learning aside from GAI. Participants recommended incorporating GAI literacy, ethical considerations, and compliance into the curriculum. Learning with GAI involved improving learning efficiency, supporting information gathering and dissemination, and facilitating patient involvement. Learning aside from GAI emphasized maintaining GAI-free learning processes, fostering higher cognitive domains of learning, and introducing more communication exercises. CONCLUSIONS: This study highlights the profound impact of GAI on medical education curricula and provides insights into curriculum reform strategies. Participants recognized the need for GAI literacy, ethical education, and adaptive learning. Further, GAI was recognized as a tool that can enhance efficiency and involve patients in education. The study also suggests that medical education should focus on competencies that GAI hardly replaces, such as clinical experience and communication. Notably, involving both faculty and students in curriculum reform discussions fosters a sense of ownership and ensures broader perspectives are encompassed.

[Hip joint synovitis associated with daclatasvir plus asunaprevir combination therapy to treat chronic HCV infection in elderly patients: a case report].

An 81-year-old woman was treated with Daclatasvir (DCV) and Asunaprevir (ASV) for chronic HCV infection. Although she developed a fever 13 days after treatment initiation, the administration of these drugs was continued under careful observation. After 33 days of treatment initiation, she developed a high fever and hip joint pain that led to hospitalization. Following MRI studies and examination of her hip joint fluid, we suspected that she had developed hip joint synovitis secondary to the use of DCV and ASV. Consequently, we discontinued the administration of both DCV and ASV, resulting in an immediate improvement in her symptoms. Eventually, she attained a sustained virological response 24 despite discontinuing the administration of DCV and ASV. Hence, unexpected adverse events, such as hip joint synovitis, should be considered in the differential diagnosis, particularly in elderly patients (≥80 years) who are treated with DCV and ASV for chronic HCV infection.

[A case of advanced gastric cancer treated with S-1/CDDP combination chemotherapy through jejunostomy].

Recently, although chemotherapy for advanced gastric cancer has been proving more highly effective, no standard chemotherapy for gastric cancer has been established. We administered S-1 combined with cisplatin (div) to a patient with advanced gastric cancer who underwent a jejunostomy because of swallowing difficulties (PS 4) due to cerebral infarction. The overall response of this chemotherapy was a partial response (PR) for 14 months. We concluded that the administration of S-1 combined with cisplatin (div) through a jejunostomy can improve the nutrition management and the quality of life (QOL) of a patient with advanced gastric cancer who is incapable of oral intake.

Sequential assessment of the intrahepatic expression of epidermal growth factor and transforming growth factor-beta1 in hepatofibrogenesis of a rat cirrhosis model.

Responses of the liver to chronic injury include inflammation, regeneration and fibrosis, which finally lead to cirrhosis. The cause of liver cirrhosis appears to be impaired proliferative capability of hepatocytes caused by continuous hepatic damage, and subsequent accumulation of extracellular matrix produced by hepatic stellate cells (HSCs). Epidermal growth factor (EGF) and transforming growth factor-beta1 (TGF-beta1) play a crucial role in hepatocyte proliferation and hepatofibrogenesis, respectively. However, sequential analyses of the intrahepatic expression of EGF and TGF-beta1 in the course of cirrhosis development have not been examined fully. In the present study, liver cirrhosis was produced in rats by intraperitoneal administration of dimethylnitrosamine (DMN), and intrahepatic mRNA expression levels of proliferating cell nuclear antigen (PCNA), EGF and TGF-beta1 were quantitatively estimated by a real-time reverse transcription-polymerase chain reaction method. Histological and semiquantitative densitometric examination of liver sections revealed that the accumulation of extracellular matrix components was increased according to the period of DMN treatment. Histological examination of liver sections of rats treated with DMN for 4 and 6 weeks revealed pre-cirrhosis and cirrhosis, respectively. Intrahepatic mRNA expression levels of PCNA and EGF correlated well. Expression levels of both molecules were increased significantly during the course of cirrhosis development, but decreased significantly at the time of complete cirrhosis manifestation. In contrast, intrahepatic TGF-beta1 expression was increased significantly according to the period of DMN treatment, and reached a peak at the time of cirrhosis manifestation. These results suggest that proliferative capability of hepatocytes was impaired by continuous liver damage due, in part, to the decrease of a hepatocyte mitogen EGF, and that increased intrahepatic TGF-beta1 activated HSCs to retrieve space lost by hepatocyte destruction, resulting in complete cirrhosis manifestation.

Usefulness of liver infiltrating CD86-positive mononuclear cells for diagnosis of autoimmune hepatitis.

AIM: Although the pathogenic mechanism underlying autoimmune hepatitis (AIH) remains unclear, the immune system is thought to be critical for the progression of the disease. Cellular immune responses may be linked to the hepatocellular damage in AIH. Recently, much attention has been focused on the critical functions of costimulatory molecules expressed on mononuclear cells in the generation of effective T cell-mediated immune responses. Analysis of costimulatory molecule expressed on mononuclear cells from the patients with AIH may give us insight into the pathogenic mechanism of hepatocellular damage in AIH. METHODS: Peripheral blood mononuclear cells (PBMC) were taken from the patients with AIH (34 cases) and healthy controls (25 cases). Liver infiltrating mononuclear cells (LIMCs) were taken from the patients with AIH (18 cases), the patient with chronic hepatitis C (CH-C) (13 cases) and the patients with fatty liver (2 cases). Using flow cytometry, the cells were analyzed for the expression of costimulatory molecules, such as CD80, CD86, and CD152 (CTLA-4). The results were compared with clinical data such as the level of gammaglobulin, histological grade, presence or absence of corticosteroids administration and the response to corticosteroids. RESULTS: The levels of CD80+, CD86+ and CD152+ PBMC were significantly reduced in the patients with AIH as compared with healthy controls. By contrast, those cells were significantly higher in LIMC than in PBMC of the patients with AIH. Especially, the level of CD86+ LIMC showed a marked increase irrespective of the degree of disease activity in the patients with AIH, although CD86+ cells were rarely present in PBMC. The levels of CD86+ cells were present in significantly higher frequency in patients with AIH than in the patients with CH-C. Furthermore, the patients with AIH with high levels of CD86+ LIMC showed good responses to corticosteroids, whereas 2 cases of AIH with low levels of CD86+ LIMC did not respond well. CONCLUSION: These results suggest that LIMC over-expressing costimulatory molecules such as CD80 and CD86 appears to play a role in the pathogenesis of AIH. Especially, CD86 molecule expressed on the LIMC may be useful for the diagnosis of AIH and for the prediction of the therapeutic effects of corticosteroids on AIH.

Reduced expression of p63 has prognostic implications for patients with esophageal squamous cell carcinoma.

The p63 gene is a member of the p53 family that plays a role in cell differentiation, development and carcinogenesis. The relationship between p63 expression and the prognosis of esophageal squamous cell carcinoma (ESCC) remains unknown. The present study examines the clinical impact of p63 in patients with ESCC. Resected specimens from 180 patients with ESCC were immunostained for p63 and p53. After establishing a cut-off value for p63 expression, we statistically examined its clinical impact and relationship to p53 expression. At a 50% cut-off value for p63 expression, the 5-year overall survival was significantly longer in p63-positive (46.4%) than -negative patients (11.1%, p=0.05). Among the 180 ESCC patients, 171 (95.0%) were p63 immunoreactive and only 9 (5.0%) were negative. The correlation between p63 status and clinicopathological parameters was not significant, although p63-negativity tended to correlate with distant metastasis (p=0.06) and clinical stage (p=0.08). Univariate analysis demonstrated significant correlations between patient survival and tumor diameter, depth of invasion, lymphatic invasion, vascular invasion, lymph node metastasis and distant metastasis. The survival of patients who did not express p63 and p53 was obviously unfavorable (p=0.03). Multivariate analysis revealed that only lymph node metastasis was a critical independent prognostic marker for overall survival (p=0.0015). Expression of p63 was not an independent prognostic factor for overall survival in this study (p=0.69). These data suggest that, although a reduced expression of p63 is infrequent, it has a prognostic impact upon patients with ESCC.

Analyses of autoantibodies against tumor-associated antigens in patients with hepatocellular carcinoma.

Autoantibodies against tumor-associated antigens (TAAs) such as insulin-like growth factor II mRNA-binding proteins (IMPs), p53, c-myc, and survivin were analyzed in patients with hepatocellular carcinoma (HCC), using recombinant proteins of these antigens. Eight of 86 (9.3%) HCC patients had one or more of these autoantibodies. However, serum alpha-fetoprotein (AFP) levels ranged within normal limits in HCC patients with anti-TAAs except for one case with anti-IMP1. One of the HCC patients had autoantibodies against IMP1, IMP3 and p53 before the diagnosis of HCC. These findings may indicate that anti-TAAs seem to be supplementary serological markers for the diagnosis of HCC in AFP-negative cases and that autoantibodies against IMP1, IMP3 and p53 are candidates for predictive markers of HCC development.

Diffuse large B-cell primary gastric lymphoma treated successfully with the CD20 monoclonal antibody (rituximab): a case with severe liver dysfunction due to liver cirrhosis and hepatocellular carcinoma.

Primary gastric lymphoma is relatively rare in the scope of gastric malignancies. Here we report a case of diffuse large B-cell primary gastric lymphoma treated successfully with the CD20 monoclonal antibody, rituximab, alone. Because the patient had a complication of severe liver dysfunction due to hepatitis C virus induced-liver cirrhosis and hepatocellular carcinoma, it was difficult to treat the primary gastric lymphoma using standard therapy such as surgical resection and cocktail chemotherapy. Therefore, rituximab was administered to the patient, resulting in complete remission of the primary gastric lymphoma. This case indicates that monotherapy using only rituximab may be a promising option for the treatment of patients with diffuse large B-cell lymphoma accompanied by severe liver dysfunction.

Genetic polymorphisms of toll-like receptor 9 influence the immune response to CpG and contribute to hyper-IgM in primary biliary cirrhosis.

The serum hallmark of primary biliary cirrhosis (PBC) is the presence of anti-mitochondrial antibodies (AMA), found in 95% of patients. However, nearly every patient with PBC, including those who are AMA-negative, has an elevation in serum IgM. This hyper-IgM is neither representative of other Ig isoforms, nor is due to the levels of AMA. In fact, we have recently reported that the hyper-IgM is an innate immune response and can be induced with CpG-B with concurrent up-regulation of toll-like receptor 9 (TLR9). Based on these observations, we performed a two-tier study. First, we quantitated TLR9 genotypes in patients with PBC and controls and correlated these data with the B cell response to CpG-B. Second, based on these data, we performed an extensive TLR9 genotyping in a large cohort of patients and controls. We report herein that the 2848 AA TLR9 genotype is associated with enhanced gene expression and higher frequency of intracellular IgM(+) B cells following CpG stimulation. Interestingly, however, despite the functional association, there is no difference in the distribution of TLR9 genotypes between patients and controls. Our data emphasize the importance of dissecting the innate immune response in PBC.

In vitro and in vivo antitumor effects of vitamin K5 on hepatocellular carcinoma.

Although a number of studies have shown that vitamins K1, K2 and K3 exerted antitumor effects on various types of rodent- and human-derived neoplastic cell lines, it has not been examined whether or not vitamin K5 also possesses antitumor activity. In the present study, we examined the antitumor effects of vitamin K5 on PLC/PRF/5 human hepatocellular carcinoma (HCC) cells in vitro and in vivo. Furthermore, we examined the mechanisms of antitumor actions of vitamin K5 not only in vitro but also in vivo. Vitamin K5 was shown to suppress the proliferation of PLC/PRF/5 cells at a concentration of 30 microM. By a flow cytometric analysis, it was shown that although vitamin K5 did not induce apoptosis on PLC/PRF/5 cells, it did induce G1 arrest on PLC/PRF/5 cells. Subsequent in vivo study using subcutaneous HCC-bearing athymic nude mice demonstrated that vitamin K5 markedly suppressed the growth of HCC tumors. Although protein expression levels of cyclin D1 and p16INK4a cyclin-dependent kinase (Cdk) inhibitor in HCC tumors were not decreased by vitamin K5 treatment, those of Cdk4 were reduced significantly by the treatment. Taken collectively, vitamin K5 could induce potent antitumor effects on HCC not only in vitro but also in vivo, at least in part by inducing G1 arrest of cell cycle through downregulation of Cdk4 expression. The results demonstrated here indicate that vitamin K5 may be a useful agent for the treatment of patients with HCC.

Safe and efficient transgene expression in rat hepatocytes induced by adenoviral administration into the biliary tract.

We examined whether retrograde intrabiliary adenoviral administration could induce safe and efficient transgene expression in hepatocytes. We administered recombinant adenovirus carrying a reporter lacZ gene retrogradely into the common bile duct of rats and evaluated the transduction efficiency of the lacZ gene in the liver histochemically by X-gal staining, and also quantitatively by a chemiluminescent reporter gene assay. Retrograde administration of adenovirus into the common bile duct was shown to successfully induce transgene expression in the liver. Although transgene expression induced by intrabiliary adenoviral administration was observed predominantly at periportal areas, a considerable number of cells expressing the transgene were detectable even in lobular and centrilobular areas. Furthermore, histochemical analysis revealed that intrabiliary adenoviral administration resulted in gene transfer into hepatocytes, but not into biliary epithelial cells. Transgene expression in the liver was transient, and pathological and biochemical analyses revealed that hepatic damage caused by intrabiliary adenoviral administration was not substantial. The results demonstrated in the present study suggest that retrograde administration of adenovirus into the common bile duct can induce safe and efficient transgene expression in hepatocytes without causing considerable adverse effects, supporting the feasibility of adenovirus-mediated gene transfer into hepatocytes in clinical settings by means of endoscopic retrograde cholangiography.

Comparison between combination therapy of percutaneous ethanol injection and radiofrequency ablation and radiofrequency ablation alone for patients with hepatocellular carcinoma.

AIM: In the present study, the characteristics of PEI-RFA treatment were further elucidated by analyzing the relationship between the volume of coagulated necrosis and the energy requirement for ablation or the amount of ethanol injected into HCC. METHODS: The volume of coagulated necrosis, total energy requirement and energy requirement for coagulation of per unit volume were examined in the groups of PEI-RFA and RFA alone using the Cool-tip RF system. RESULTS: The results showed that the volume of coagulated necrosis induced was significantly larger in PEI-RFA group than in routine RFA group, when the total energy administered was comparable in both groups. In PEI-RFA, enlargement of coagulated necrosis was admitted in 3 dimensions and the amount of energy requirement per unit volume of coagulated necrosis was negatively correlated with the amount of ethanol injected into HCC. CONCLUSION: These results suggest that, compared to RFA alone, PEI-RFA enables to induce comparable coagulated necrosis with smaller energy requirement, and that PEI-RFA is likely to be less invasive than RFA alone irrespective of inducing enhanced coagulated necrosis. Thus, simple prior injection of ethanol may make RFA treatment more effective and less invasive for the treatment of patients with HCC.

Comparison study of the expressions of myristoylated alanine-rich C kinase substrate in hepatocellular carcinoma, liver cirrhosis, chronic hepatitis, and normal liver.

The myristoylated alanine-rich C kinase substrate (MARCKS) is a prominent substrate for protein kinase C (PKC) in a variety of cells. The aim of this study was not only to evaluate the expression and localization of MARCKS in various pathological liver tissues, including HCC, but also to analyze the difference in MARCKS expression between hepatitis virus-induced HCC and cirrhosis. The level of MARCKS and its phosphorylated proteins, as well as its localization, were determined using Western blot and/or immunohistochemistry in HCC and other pathological liver tissues. We also analyzed the change of MARCKS localization on the influence of MARCKS phosphorylation in the HLF cancer cell line by phosphorylation study. In addition, the relationship between MARCKS expression and proliferative activity was studied in HCC. In the immunohistochemical study, a very small amount of MARCKS protein was found along the contour of the hepatocellular membrane in normal liver and in cases of chronic hepatitis. MARCKS was up-regulated in liver cirrhosis tissue and was localized in the cytoplasm of hepatocytes. The expression of MARCKS was down-regulated in HCC tissues, as compared with non-tumorous liver cirrhosis tissues from the same patients. Furthermore, MARCKS was serine-phosphorylated in liver cirrhosis and HCC, and phosphorylated MARCKS was detected in a cytosolic fraction of these tissues. In a phosphorylation study using the HLF HCC cell line, MARCKS was displaced from the plasma membrane to the cytosol following the activation of protein kinase C (PKC) by phorbol 12-myristrate 13-acetate (PMA). Furthermore, the activity of cyclin D1 and cyclin E kinases was found to be higher in HCCs with low MARCKS expression than in HCCs with high MARCKS expression. These results suggest that up-regulation of MARCKS might be essential in the generation of cirrhotic nodules through chronic hepatitis from normal liver, and that the phosphorylation and/or down-regulation of MARCKS might play an important role in the development and progression of HCC from liver cirrhosis.

Genetic polymorphisms influencing xenobiotic metabolism and transport in patients with primary biliary cirrhosis.

Epidemiological data suggest that environmental factors may trigger autoimmunity in genetically susceptible individuals. In primary biliary cirrhosis (PBC), it has been postulated that halogenated xenobiotics can modify self-molecules, facilitating the breakdown of tolerance to mitochondrial antigens. The transport and metabolism of xenobiotics is highly dependent on key genetic polymorphisms that alter enzymatic phenotype. We analyzed genomic DNA from 169 patients with PBC and 225 geographically and sex-matched healthy subjects for polymorphisms of genes coding for cytochromes P450 (CYPs) 2D6 (CYP2D6*4, CYP2D6*3, CYP2D6*5, and CYP2D6*6) and 2E1 (cl/c2), multidrug resistance 1 (MDR1 C3435T) P-glycoprotein, and pregnane X receptor (PXR C-25385T, C8055T, and A7635G). We compared the genotype frequencies in patients and controls and also correlated polymorphisms with PBC severity. The distributions of the studied genotypes did not significantly differ between patients and controls. However, when clinical characteristics of patients with PBC were compared according to genotype, the CYP2E1 c2 allele was associated with signs of more severe disease. In conclusion, genetic polymorphisms of CYP 2D6 and 2E1, PXR, and MDR1 do not appear to play a role in the onset of PBC.

Biotin-rich intranuclear inclusions in morule-lacking adenocarcinoma of the gallbladder: a new category of "neoplastic/non-morular" lesions.

Biotin-rich intranuclear inclusions, also called "optically clear nuclei," are observed in various neoplastic and non-neoplastic lesions, including pregnancy-related endometrium and benign and malignant neoplasms with morular structures. A recent study reported that lesions with biotin-rich intranuclear inclusions can be classified as "(non-neoplastic) pregnancy-related endometrial" and as "(neoplastic) morular" category. In the present report, we describe two cases of well-differentiated adenocarcinoma of the gallbladder in which biotin-rich intranuclear inclusions were found without morular structures. Immunohistochemically, as reported previously, the intranuclear inclusions were positive for biotin and two biotin-binding enzymes (pyruvic acid carboxylase and propionyl CoA carboxylase). Intranuclear expression of beta-catenin was also observed in neoplastic cells with and without intranuclear inclusion. We also detected a frame shift mutation of APC gene in one case but no mutation of beta-catenin gene in both cases. Although intranuclear expression of beta-catenin by mutation of APC gene might contribute to carcinogenesis in our cases, the relationships among intranuclear expressions of beta-catenin, biotin, biotin-binding enzymes and intranuclear inclusions remain unclear. Our cases are the first neoplastic lesions with biotin-rich intranuclear inclusions that lacked morular structures. We propose a new "neoplastic/non-morular" category for lesions with biotin-rich intranuclear inclusions.

Successful laparoscopic radiofrequency ablation of hepatocellular carcinoma adhered to the mesentery after transcatheter arterial embolization.

A 54-year-old male with hepatocellular carcinoma (HCC) underwent transcatheter arterial embolization (TAE) at a nearby hospital. He was then referred to our hospital for the purpose of additional treatment of HCC. Because TAE was not a complete therapy and HCC was growing and protruding from the left lobe of the liver, laparoscopic radio-frequency ablation (RFA) was chosen for the treatment of HCC. After inserting a laparoscope into the abdominal cavity, it was observed that HCC unexpectedly adhered to the mesentery as a result of TAE performed previously. After cutting off the adhered mesentery and removing it from the tumor, the combination therapy of percutaneous ethanol injection and RFA (PEI-RFA), developed at our department, was performed on the tumor. The tumor was successfully abrogated by PEI-RFA and the sufficient safety margin was confirmed by computed tomography after the treatment.

Adenovirus-mediated gene transfer into rat livers: comparative study of retrograde intrabiliary and antegrade intraportal administration.

To examine the feasibility of liver-directed in vivo gene therapy, we administered recombinant adenoviruses carrying a reporter lacZ gene retrogradely into the common bile duct of rats, as well as antegradely into the portal vein. Transduction efficiency of the lacZ gene in the liver was estimated not only histochemically by X-gal staining, but also quantitatively by a chemiluminescent reporter gene assay. Retrograde infusion of adenoviruses into the common bile duct was shown to successfully induce transgene expression in the liver. Transduction efficiency induced by intrabiliary adenoviral administration was not significantly different from that induced by intraportal adenoviral administration. Although transgene expression induced not only by intraportal, but also by intrabiliary adenoviral administration was observed predominantly at periportal areas, a considerable number of cells expressing the transgene were detectable even in lobular and centrilobular areas. Mild infiltration of inflammatory cells into the liver and mild hyperplastic changes of hepatocytes were observed after intrabiliary and intraportal adenoviral administration. However, hepatic damage estimated pathologically was not substantial. Furthermore, although intrabiliary and intraportal adenoviral administration resulted in very mild elevation of liver-related serum biochemical parameters, apparent complications were not observed in any rats. Our results demonstrated in the present study suggest that retrograde administration of adenoviruses into the common bile duct can induce efficient transgene expression in the liver without causing severe adverse effects, supporting the feasibility of adenovirus-mediated gene transfer into the liver in clinical settings by means of endoscopic retrograde cholangiography.

Plutonium(VI) accumulation and reduction by lichen biomass: correlation with U(VI).

The uptake of plutonium(VI) and uranium(VI) by lichen biomass was studied in the foliose lichen Parmotrema tinctorum to elucidate the migration behavior of Pu and U in the terrestrial environment. Pu and U uptake by P. tinctorum averaged 0.040+/-0.010 and 0.055+/-0.015 g gdry (-1), respectively, after 96 h incubation with 4.0 x 10(14) mol 1(-1) Pu solutions of pH 3, 4 and 5. SEM observations showed that the accumulated Pu is evenly distributed on the upper and lower surfaces of P. tinctorum, in contrast to U(VI), which accumulated in both cortical and medullary layers. UV/VIS absorption spectroscopy demonstrates that a fraction of Pu(VI) in the solution is reduced to Pu(V) by the organic substances released from P. tinctorum, and the accumulated Pu on the surface is reduced to Pu(IV), while U(VI) keeps the oxidation state of VI. Since the solubility of Pu(IV) hydroxides is very low, reduced Pu(VI) does not penetrate to the medullary layers, but is probably precipitated as Pu(IV) hydroxides on the cortical lichen surface. It is concluded that the uptake and reduction of Pu(VI) by lichens is important to determine the mobilization and oxidation states of Pu in the terrestrial environment.

E-cadherin expression in patients with esophageal squamous cell carcinoma: promoter hypermethylation, Snail overexpression, and clinicopathologic implications.

Hypermethylation in the E-cadherin promoter region and expression of the transcription factor Snail were analyzed in 41 cases of esophageal squamous cell carcinoma (ESCC) and paired normal squamous epithelium by methylation-specific polymerase chain reaction (PCR) and reverse transcription-polymerase chain reaction (RT-PCR) to clarify the mechanism regulating E-cadherin deletion; 93 cases of ESCC were analyzed immunohistochemically to determine the clinicopathologic impact of E-cadherin deletion. Hypermethylation of the E-cadherin promoter and Snail overexpression were detected in 25 cases (61%) by methylation-specific PCR and 34 cases (83%) by RT-PCR, respectively. Reduced E-cadherin expression, observed immunohistochemically in 55 cases (59%), correlated with hypermethylation (P = .0011) but not Snail overexpression (P = .685). Hypermethylation and Snail overexpression correlated significantly with E-cadherin deletion (P = .0018). Snail overexpression was unrelated to clinicopathologic factors. Reduced E-cadherin expression correlated with tumor invasion (P = .019) and vascular invasion (P = .052) but not other factors. E-cadherin deletion had prognostic impact in univariate (P = .023) and multivariate (P = .034) analyses. E-cadherin deletion was regulated by hypermethylation and Snail expression. Examination of reduced E-cadherin expression is important for assessing biologic behavior, including clinical outcome, in patients with ESCC.