Ruptured duodenal varices after endoscopic ligation of esophageal varices: an autopsy case.
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Aged↗
Biomedical subjects
Hitoshi Takagi
Publications and source records attributed to Hitoshi Takagi.
Randomized, double-blind, placebo-controlled trial of bovine lactoferrin in patients with chronic hepatitis C.
Several studies have suggested that lactoferrin administration may decrease the serum level of hepatitis C virus (HCV) RNA in patients with chronic hepatitis C. The aim of the present study was to confirm the efficacy of orally administered bovine lactoferrin (bLF) in patients with chronic hepatitis C. The patients with chronic hepatitis C randomly received either oral bLF at a dose of 1.8 g daily for 12 weeks, or an oral placebo. The primary endpoint was the virologic response, defined as a 50% or greater decrease in serum HCV RNA level at 12 weeks compared with the baseline. The secondary endpoint was the biochemical response, which was defined as a 50% or greater decrease in the serum alanine aminotransferase (ALT) level at 12 weeks compared with the baseline. One hundred and ninety-eight of 199 patients were evaluable for efficacy and safety. bLF treatment was well tolerated and no serious toxicities were observed. A virologic response was achieved in 14 of 97 patients (14.4%) in the bLF group, and 19 of 101 (18.8%) in the placebo group. There was no significant difference in virologic response rates between the two groups (-4.4%, 95% confidence interval -14.8, 6.1). In addition, bLF intake did not have any favorable effect on the serum ALT level. The virologic responses were not different between two groups in any subgroup analysis. In conclusion, orally administered bLF does not demonstrate any significant efficacy in patients with chronic hepatitis C.
Administration, Oral↗
The use of partial splenic artery embolization made it possible to administer interferon and ribavirin therapy in a liver transplant patient with fibrosing cholestatic hepatitis C complicated with thrombocytopenia.
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Antiviral Agents↗
Lack of macrophage migration inhibitory factor protects mice against concanavalin A-induced liver injury.
BACKGROUND: Macrophage migration inhibitory factor (MIF) is involved in inflammatory and immune-mediated diseases but the role of MIF in liver injury has not yet been elucidated. METHODS: We investigated biochemically, histologically and immunologically the character of MIF in concanavalin A (Con A)-induced T-cell-mediated liver injury using MIF knockout (KO) mice and wild-type (WT) mice. RESULTS: MIF KO mice showed significantly decreased serum alanine aminotransferase values and suppressed histological change with massive necrosis of the hepatic parenchymal cells and infiltration of inflammatory cells compared with their WT counterparts. This protection was not mediated by either tumor necrosis factor-alpha or interferon-gamma, which are critical mediators of Con A-induced liver injury, as their serum concentrations were shown to be similar in MIF KO and WT mice. On the other hand, a flow cytometric analysis demonstrated that the number of activated hepatic leukocytes decreased more in the MIF KO mice than in the WT mice. CONCLUSIONS: A lack of MIF protected the mice from Con A-induced liver injury. Controlling the MIF activity may be a useful therapeutic strategy for treating such T-cell activation-associated liver diseases as autoimmune hepatitis and viral hepatitis.
Alanine Transaminase↗
Zinc is a negative regulator of hepatitis C virus RNA replication.
BACKGROUND/AIMS: Hepatitis C virus (HCV) infection is a significant global public health problem. In clinical studies, zinc has been closely related to the pathogenesis of chronic hepatitis C. However, the role of zinc in both viral replication and the expression of viral proteins remains unclear. We aimed to clarify the effect of zinc on the replication of HCV in vitro. METHODS: We incubated subgenomic HCV replicon cells (sO) and genome-length HCV RNA-replicating cells (O) treated with several chemicals including trace elements. Total RNAs were collected and subjected to real-time reverse-transcriptase polymerase chain reaction in order to examine the level of HCV RNA replication, and Western blotting was performed to confirm the expression of viral proteins. RESULTS: Iron salts and interferon-alpha suppressed HCV RNA replication and protein expression in both sO and O cells. Zinc salts effectively reduced the viral replication in the genome-length HCV RNA replication system but not in the subgenomic HCV replicon system. CONCLUSIONS: We demonstrated that zinc may play an important role as a negative regulator of HCV replication in genome-length HCV RNA-replicating cells. Zinc supplementation thus appears to offer a novel approach to the development of future strategies for the treatment of intractable chronic hepatitis C.
Cell Line↗
Time-lapse imaging of vitreoretinal angiogenesis originating from both quiescent and mature vessels in a novel ex vivo system.
PURPOSE: Diabetic retinopathy (DR) is an angiogenic disease that leads to severe visual loss. However, adequate animal models of vitreoretinal neovascularization in proliferative diabetic retinopathy (PDR) have not yet been described. The purpose of this study was to develop a novel ex vivo system for assessing vitreoretinal angiogenic processes that originate from both quiescent and mature vessels that could be observed with time-sequential imaging. METHODS: The retinas of 7- to 8-week-old mice were cultured for 4 days, with or without several growth factors with novel procedures, and immunohistochemistry was performed. The retinas from Tie2-GFP mice were cultured with vascular endothelial growth factor (VEGF), and time-sequential imaging of vitreoretinal angiogenesis was acquired. RESULTS: Vascular sprouts were induced by both VEGF and placenta growth factor, but not by insulin-like growth factor-1, basic fibroblast growth factor or angiopoietin-2. In explants with or without VEGF, perivascular mural cells were dissociated from endothelial cells, which is an important step during angiogenesis and in the progression of DR. Furthermore, use of time-lapse observations of retinal neovascularization events visualized that the first step in vascular sprout emergence from quiescent vessels was a single cell extension. The leading edges of a sprouting endothelial cell extended and retracted in a sequential manner. From newly formed vessels, additional vascular sprouts then emerged and new vessels fused to each other, resulting in vascular branching. CONCLUSIONS: Time-lapse imaging of this system visualized the dynamic process in vitreoretinal neovascularization from quiescent and mature vessels.
Animals↗
Solitary mandibular metastasis as an initial manifestation of hepatocellular carcinoma.
Oral metastases from hepatocellular carcinoma are very rare. We encountered a case of hepatocellular carcinoma with a solitary metastasis to the mandible as an initial manifestation. The patient was a 76-year-old man who was admitted for left mandibular swelling. A biopsy specimen of mandible was suspected to be a metastatic tumor. The histological findings, abdominal computed tomography, bone scintigraphy, and F-18 fluorodeoxyglucose-positron emission tomography (FDG-PET) revealed it to be a solitary metastasis from hepatocellular carcinoma. As a result, he was diagnosed to have liver cirrhosis due to a hepatitis C virus infection and hepatocellular carcinoma with a solitary metastasis to the mandible. The primary lesion was treated with transcatheter arterial embolization (TAE), and the metastasis to the mandible was surgically resected. The patient survived for 9 months after treatment without recurrence.
Aged↗
Ectopic varices in a right diaphragm that ruptured into the pleural cavity.
The term ectopic varices is used to describe dilated portosystemic collateral veins in unusual locations other than the gastroesophageal region. We recently experienced a rare case of ectopic varices that developed in the right diaphragm and ruptured into the pleural cavity. A 68-year-old female with hepatocellular carcinoma complicated with liver cirrhosis was admitted due to an acute onset of dyspnea and right bloody pleural effusion. Because of the patient's advanced hepatocellular carcinoma and poor condition, conservative therapies such as hemostats and blood transfusion were selected. Even though the bleeding to the pleural cavity stopped spontaneously, the patient died due to a progression of liver failure. Autopsy revealed a huge collateral vein in the right diaphragm. The etiology, prevalence, relationship with portal hypertension, and treatment of ectopic varices are discussed herein.
Aged↗
EphrinA1 inhibits vascular endothelial growth factor-induced intracellular signaling and suppresses retinal neovascularization and blood-retinal barrier breakdown.
The Eph receptor/ephrin system is a recently discovered regulator of vascular development during embryogenesis. Activation of EphA2, one of the Eph receptors, reportedly suppresses cell proliferation and adhesion in a wide range of cell types, including vascular endothelial cells. Vascular endothelial growth factor (VEGF) plays a primary role in both pathological angiogenesis and abnormal vascular leakage in diabetic retinopathy. In the study described herein, we demonstrated that EphA2 stimulation by ephrinA1 in cultured bovine retinal endothelial cells inhibits VEGF-induced VEGFR2 receptor phosphorylation and its downstream signaling cascades, including PKC (protein kinase C)-ERK (extracellular signal-regulated kinase) 1/2 and Akt. This inhibition resulted in the reduction of VEGF-induced angiogenic cell activity, including migration, tube formation, and cellular proliferation. These inhibitory effects were further confirmed in animal models. Intraocular injection of ephrinA1 suppressed ischemic retinal neovascularization in a dose-dependent manner in a mouse model. At a dose of 125 ng/eye, the inhibition was 36.0 +/- 14.9% (P < 0.001). EphrinA1 also inhibited VEGF-induced retinal vascular permeability in a rat model by 46.0 +/- 10.0% (P < 0.05). These findings suggest a novel therapeutic potential for EphA2/ephrinA1 in the treatment of neovascularization and vasopermeability abnormalities in diabetic retinopathy.
Animals↗
Overexpression of NK2 inhibits liver regeneration after partial hepatectomy in mice.
AIM: To investigate the in vivo effects of NK2 on liver regeneration after partial hepatectomy (PH). METHODS: Survival after PH was observed with 21 NK2 transgenic mice and 23 wild-type (WT) mice over 10 d. Liver regeneration was analyzed using histology and immunohistochemistry. Expressions of genes were analyzed using Northern blot analysis, immunoprecipitation and immunoblotting, and reverse transcriptase polymerase chain reaction assay. Kaplan-Meier method and the log-rank test were used for analyzing the survival after PH. Differences in the results of immunohistochemistry and percentage of liver regeneration was determined by the Student's t-test. RESULTS: More than half of NK2 transgenic mice died within 48 h after PH. After PH, increased deposition of small lipid droplets in hepatocytes was evident and hepatic proliferation was inhibited in NK2 transgenic mice. The hepatic expression and kinase activity of HGF receptor, c-Met, were unchanged among WT mice and NK2 transgenic mice after PH. The expression of tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) in liver tissues were prolonged in NK2 transgenic mice that died after PH. CONCLUSION: Our findings indicate that over-expression of NK2 inhibits liver regeneration after PH.
Animals↗
Concordance of ulcerative colitis in monozygotic twin sisters.
The etiology of inflammatory bowel disease is multifactorial and appears to combine both genetic and environmental factors. We experienced here a rare occurrence of woman monozygotic twins with ulcerative colitis (UC). A 45-year-old woman (the elder monozygotic twin) was admitted to our hospital because of bloody diarrhea occurring over 10 times per day, abdominal pain and fever. She was diagnosed as UC at the age of 22, and repeated the relapse and remission. She was diagnosed as relapse of UC and total colitis type. Her younger monozygotic twin sister also suffered from UC at the age of 22. Human leukocyte antigen was examined serologically with DNA type in both patients. DRB1*1502, which was previously shown to be dominant in Japanese patients with UC, was not observed in this case. Although the concordance in monozygotic twin in UC is reported to be 6.3-18.8%, the concordant case like this is relatively rare. We report this rare case of UC and the previously reported cases are also discussed.
Colitis, Ulcerative↗
Erythropoietin as a retinal angiogenic factor.
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Analysis of Variance↗
Role of nuclear receptor CAR in carbon tetrachloride-induced hepatotoxicity.
AIM: To investigate the precise roles of CAR in CCl(4)-induced acute hepatotoxicity. METHODS: To prepare an acute liver injury model, CCl(4) was intraperitoneally injected in CAR+/+ and CAR-/- mice. RESULTS: Elevation of serum alanine aminotransferase and extension of centrilobular necrosis were slightly inhibited in CAR-/- mice compared to CAR+/+ mice without PB. Administration of a CAR inducer, PB, revealed that CCl(4)-induced liver toxicity was partially inhibited in CAR-/- mice compared with CAR+/+ mice. On the other hand, androstanol, an inverse agonist ligand, inhibited hepatotoxicity in CAR+/+ but not in CAR-/- mice. Thus, CAR activation caused CCl(4) hepatotoxicity while CAR inhibition resulted in partial protection against CCl(4)-induced hepatotoxicity. There were no differences in the expression of CYP2E1, the main metabolizing enzyme for CCl(4), between CAR+/+ and CAR-/- mice. However, the expression of other CCl(4)-metabolizing enzymes, such as CYP2B10 and 3A11, was induced by PB in CAR+/+ but not in CAR-/- mice. Although the main pathway of CCl(4)-induced acute liver injury is mediated by CYP2E1, CAR modulates its pathway via induction of CYP2B10 and 3A11 in the presence of activator or inhibitor. CONCLUSION: The nuclear receptor CAR modulates CCl(4)-induced liver injury via induction of CCl(4)-metabolizing enzymes in the presence of an activator. Our results suggest that drugs interacting with nuclear receptors such as PB might play critical roles in drug-induced liver injury or drug-drug interaction even though such drugs themselves are not hepatotoxic.
Androstanols↗
Adult onset type II citrullinemia as a cause of non-alcoholic steatohepatitis.
Adult onset type II citrullinemia (CTLN2) is an autosomal recessive disease accompanied with hyperammonemia and a sudden onset of psychiatric disorders. We demonstrated three male patients with CTLN2 having a liver histology of non-alcoholic steatohepatitis (NASH). Patients with NASH were analyzed for the causative gene of CTLN2, SLC25A13 and discussed.
Adolescent↗
Diffuse hepatic vascular malformations with right aortic arch.
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Aged↗
Erythropoietin as a retinal angiogenic factor in proliferative diabetic retinopathy.
BACKGROUND: Although vascular endothelial growth factor (VEGF) is a primary mediator of retinal angiogenesis, VEGF inhibition alone is insufficient to prevent retinal neovascularization. Hence, it is postulated that there are other potent ischemia-induced angiogenic factors. Erythropoietin possesses angiogenic activity, but its potential role in ocular angiogenesis is not established. METHODS: We measured both erythropoietin and VEGF levels in the vitreous fluid of 144 patients with the use of radioimmunoassay and enzyme-linked immunosorbent assay. Vitreous proliferative potential was measured according to the growth of retinal endothelial cells in vitro and with soluble erythropoietin receptor. In addition, a murine model of ischemia-induced retinal neovascularization was used to evaluate erythropoietin expression and regulation in vivo. RESULTS: The median vitreous erythropoietin level in 73 patients with proliferative diabetic retinopathy was significantly higher than that in 71 patients without diabetes (464.0 vs. 36.5 mIU per milliliter, P<0.001). The median VEGF level in patients with retinopathy was also significantly higher than that in patients without diabetes (345.0 vs. 3.9 pg per milliliter, P<0.001). Multivariate logistic-regression analyses indicated that erythropoietin and VEGF were independently associated with proliferative diabetic retinopathy and that erythropoietin was more strongly associated with the presence of proliferative diabetic retinopathy than was VEGF. Erythropoietin and VEGF gene-expression levels are up-regulated in the murine ischemic retina, and the blockade of erythropoietin inhibits retinal neovascularization in vivo and endothelial-cell proliferation in the vitreous of patients with diabetic retinopathy in vitro. CONCLUSIONS: Our data suggest that erythropoietin is a potent ischemia-induced angiogenic factor that acts independently of VEGF during retinal angiogenesis in proliferative diabetic retinopathy.
Animals↗
Angiopoietin-1 attenuates H2O2-induced SEK1/JNK phosphorylation through the phosphatidylinositol 3-kinase/Akt pathway in vascular endothelial cells.
Oxidative stress activates various signal transduction pathways, including Jun N-terminal kinase (JNK) and its substrates, that induce apoptosis. We reported here the role of angiopoietin-1 (Ang1), which is a prosurvival factor in endothelial cells, during endothelial cell damage induced by oxidative stress. Hydrogen peroxide (H2O2) increased apoptosis of endothelial cells through JNK activation, whereas Ang1 inhibited H2O2-induced apoptosis and concomitant JNK phosphorylation. The inhibition of H2O2-induced JNK phosphorylation was reversed by inhibitors of phosphatidylinositol (PI) 3-kinase and dominant-negative Akt, and constitutively active-Akt attenuated JNK phosphorylation without Ang1. These data suggested that Ang1-dependent Akt phosphorylation through PI 3-kinase leads to the inhibition of JNK phosphorylation. H2O2-induced phosphorylation of SAPK/Erk kinase (SEK1) at Thr261, which is an upstream regulator of JNK, was also attenuated by Ang1-dependent activation of the PI 3-kinase/Akt pathway. In addition, Ang1 induced SEK1 phosphorylation at Ser80, suggesting the existence of an additional signal transduction pathway through which Ang1 attenuates JNK phosphorylation. These results demonstrated that Ang1 attenuates H2O2-induced SEK1/JNK phosphorylation through the PI 3-kinase/Akt pathway and inhibits the apoptosis of endothelial cells to oxidative stress.
Angiopoietin-1↗
Emergency balloon-occluded retrograde transvenous obliteration for gastric varices.
BACKGROUND: We evaluated the efficacy of emergency balloon-occluded retrograde transvenous obliteration (B-RTO) performed within 24 h after initial hemostasis for the prevention of rebleeding from ruptured gastric varices. METHODS: From December 1995 to March 2003, 11 patients who had undergone B-RTO within 24 h after the control of gastric variceal bleeding at Maebashi Red Cross Hospital were investigated. They were followed up for complete eradication, recurrence of varices, and rebleeding. Efficacy was determined by endoscopic examination and computed tomography. RESULTS: The 4 patients with acute bleeding from ruptured gastric varices were treated with endoscopic therapy-endoscopic variceal ligation (EVL) in 2 patients, and clipping treatment in 2. Initial hemostasis was achieved in all 4; the other 7 patients had already stopped bleeding at endoscopy. After hemostasis was achieved, emergency B-RTO was immediately performed within 24 h and was successful in all 11 patients. Ten (90.9%) of the 11 gastric varices were obliterated and the other 1 (9.1%) was diminished in size. During the mean follow-up period of 1136 days, no rebleeding or recurrence as found. Four patients died during the follow-up period, but none died from variceal bleeding. Survival rates were 90.9% and 70.7%, respectively, at 1 year and 3 years. In 6 patients, development of esophageal varices appeared during the follow-up period, all of which were controlled by usual endoscopic therapy. No severe side effects were found after the B-RTO treatment. CONCLUSIONS: Emergency B-RTO is an effective treatment for the prevention of rebleeding from ruptured gastric varices.
Adult↗