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Masahiro Kido

Publications and source records attributed to Masahiro Kido.

13 recordsLinked to original sources
PubMed2006

Human thioredoxin-1 ameliorates experimental murine colitis in association with suppressed macrophage inhibitory factor production.

BACKGROUND & AIMS: Thioredoxin-1 (TRX) is a small multifunctional protein with antioxidative and redox-regulating functions. In this study, we investigated the significance of TRX in patients with inflammatory bowel disease (IBD) and the ability and mechanism to ameliorate experimental colitis. METHODS: Serum TRX and macrophage migration inhibitory factor (MIF) levels were measured in patients with IBD. The effects of TRX were evaluated in a dextran sulfate sodium (DSS)-induced colitis model by comparing TRX-overexpressing transgenic (TRX-TG) and control mice. We further evaluated the effect of recombinant human TRX (rhTRX) administration on DSS-induced colitis and colonic inflammation of interleukin (IL)-10 knockout (IL-10 KO) mice. Colonic inflammation was examined clinically and histologically. Proinflammatory cytokine levels were examined in colonic tissues, and MIF levels were measured in colonic tissues and sera in mice. The effect of TRX on MIF production was also analyzed in vitro. RESULTS: Serum TRX and MIF levels were significantly higher in patients with IBD than normal controls, and TRX levels correlated with disease activity. TRX significantly ameliorated DSS-induced colitis and colonic inflammation of IL-10 KO mice. Increase of tumor necrosis factor-alpha and interferon-gamma in colonic tissues was significantly suppressed in TRX-TG mice compared with wild-type mice. MIF levels in colonic tissues and sera were significantly lower in TRX-TG mice than in wild-type mice, irrespective of DSS administration. Anti-TRX treatment exacerbated DSS-induced colitis. In vitro studies demonstrated that rhTRX suppressed MIF production in human monocyte cells. CONCLUSIONS: TRX might have a potential as a novel therapeutic agent for the treatment of IBD.

Animals↗
PubMed2006

Relative adrenal insufficiency manifested with multiple organ dysfunction in a liver transplant patient.

Relative adrenal insufficiency is now a well-known clinical condition that occurs in critically ill patients particularly with septic complication. However, this pathology has long been unrecognized until recently in liver transplantation patients, for whom postoperative immunosuppressive therapies almost always comprise corticosteroids. We report an obvious case of relative adrenal insufficiency manifested by severe multiple organ dysfunction in a recipient after living donor liver transplantation (LDLT). A 38-year-old woman with multiple hepatocellular carcinoma developed refractory liver failure 2 months after the completion of the dual treatment; namely a cytoreductive right hepatectomy for bulky main tumors followed by 2 courses of percutaneous isolated hepatic perfusion for residual tumors in the remnant liver. She underwent a right-lobe LDLT, and postoperative immunosuppression was initiated with a low-dose tacrolimus monotherapy without corticosteroid because of a severe septic condition before transplantation. Postoperatively, she developed progressive hyperbilirubinemia, renal dysfunction, and coagulopathy. As the corticotropin stimulation test suggested the relative adrenal insufficiency, corticosteroid was commenced 40 days after LDLT. Thereafter, multiple organ dysfunction resolved dramatically and promptly. The patient is presently alive and well with completely normalized liver function 45 months after LDLT.

Adrenal Insufficiency↗
PubMed2006

Clinical significance of serum thioredoxin 1 levels in patients with acute pancreatitis.

OBJECTIVE: Thioredoxin 1 (TRX-1), a redox-regulating protein with antioxidant activity, is induced by oxidative stress, and serum TRX-1 levels are recognized as an oxidative-stress marker. The aim of this study was to clarify the clinical significance of serum TRX-1 levels in patients with acute pancreatitis (AP) and evaluate the usefulness of this measurement in assessing disease severity. METHODS: Serum TRX-1 levels were determined on admission in 18 patients with severe AP and 36 patients with mild AP. We also investigated the relationship between serum TRX-1 levels and clinical and laboratory data. RESULTS: The median serum TRX-1 levels on admission were 54.9 ng/mL in mild AP and 118.8 ng/mL in severe AP. When the cutoff value for TRX-1 in predicting severe AP was determined to be 100 ng/mL, its sensitivity, specificity, and accuracy were 83.3%, 94.4%, and 90.7%, respectively. A significant correlation was observed between serum TRX-1 levels and Ranson score (r = 0.674), C-reactive protein (r = 0.718), interleukin 6 (r = 0.712), leukocyte count (r = 0.642), and serum amylase (r = 0.436). CONCLUSIONS: Serum TRX-1 levels significantly correlate with AP severity. TRX-1 should constitute a reliable oxidative-stress marker for the evaluation of AP severity in relation to oxidative stress.

Acute Disease↗
PubMed2006

Identification of a novel autoantibody against pancreatic secretory trypsin inhibitor in patients with autoimmune pancreatitis.

OBJECTIVES: Although autoimmune pancreatitis (AIP) has been recently recognized as a new disease entity of chronic pancreatitis, the clinical diagnosis of the disease remains disputed. Autoantibodies against carbonic anhydrase II and lactoferrin are detected in most patients with AIP, but not in about 10%. We undertook this study to determine whether additional autoantibodies are present in the serum level of AIP patients. METHODS: We recruited 26 patients with AIP for the study. For comparison, we also recruited 53 patients with various pancreatic diseases and 12 healthy subjects. We immunoscreened human pancreatic cDNA library using patients' sera. Positive clones were analyzed by DNA sequencing and were constructed into a pGEX-4T-1 expression vector. The recombinant proteins were used as antigens in enzyme-linked immunosorbent assay to screen the subjects' sera for autoantibodies. RESULTS: We cloned a cDNA encoding the pancreatic secretory trypsin inhibitor (PSTI). Among 26 patients with AIP, autoantibodies against PSTI were significantly positive in 11 (42.3%) by western blotting and in 8 (30.8%) by enzyme-linked immunosorbent assay, respectively. However, none of control subjects was positive for anti-PSTI antibodies. CONCLUSIONS: These findings suggest that PSTI may be related to the pathogenesis of AIP, and autoantibodies against PSTI can be a useful diagnostic marker for the disease.

Aged↗
PubMed2005

Protective roles of redox-active protein thioredoxin-1 for severe acute pancreatitis.

Severe acute pancreatitis is a disease with high mortality, and infiltration of inflammatory cells and reactive oxygen species have a crucial role in the pathophysiology of this disease. Thioredoxin-1 (TRX-1) is an endogenous redox-active multifunctional protein with antioxidant and anti-inflammatory effects. TRX-1 is induced in various inflammatory conditions and shows cytoprotective effects. The aim of the present study was to clarify the protective roles of TRX-1 in the host defense mechanism against severe acute pancreatitis. Experimental acute pancreatitis was induced by intraperitoneal administration of cerulein, a CCK analog, and aggravated by lipopolysaccharide injection in transgenic mice overexpressing human TRX-1 (hTRX-1) and control C57BL/6 mice. Transgenic overexpression of hTRX-1 strikingly attenuated the severity of experimental acute pancreatitis. TRX-1 overexpression suppressed neutrophil infiltration as determined by myeloperoxidase activity, oxidative stress as determined by malondialdehyde concentration, and cytoplasmic degradation of inhibitor of kappaB-alpha, thereby suppressing proinflammatory cytokines, tumor necrosis factor-alpha, interleukin-1beta, and interleukin-6; a neutrophil chemoattractant, keratinocyte-derived chemokine; and inducible nitric oxide synthase in the pancreas. Administration of recombinant hTRX-1 also suppressed neutrophil infiltration, reduced the inflammation of the pancreas and the lung, and improved the mortality rate. The present study suggests that TRX-1 has potent antioxidant and anti-inflammatory actions in experimental acute pancreatitis and might be a new therapeutic strategy to improve the prognosis of severe acute pancreatitis.

Acute Disease↗
PubMed2005

Handcrafted two-channel colonoscope for grasping-forceps-assisted resection of giant pedunculated polyps.

BACKGROUND: Colonoscopic polypectomy of giant pedunculated polyps has an increased risk of bleeding and is technically difficult. To facilitate the removal of the polyps, we handcrafted a two-channel colonoscope and applied it for grasping-forceps-assisted resection. METHODS: We easily handcrafted a two-channel colonoscope by taping a plastic tube along the shaft of a standard colonoscope and used it for the technique in 10 patients with 12 giant pedunculated polyps. OBSERVATIONS: The colonoscope with forceps assistance proved to be satisfactory for handling detachable and polypectomy snares. Immediate bleeding occurred in one patient because the detachable snare could not be maneuvered over the polyp. In 3 patients, the plastic tube became mobile during the procedure because the tape that attached the tube became loose. No other complications occurred. CONCLUSIONS: A handcrafted two-channel colonoscope for grasping-forceps-assisted resection of giant pedunculated polyps is effective for the prevention of postpolypectomy bleeding and the reduction of technical difficulties.

Adult↗
PubMed2005

[Sustained complete remission with reductive surgery plus percutaneous isolated hepatic perfusion (PIHP) for bilobar multiple hepatocellular carcinoma with portal venous tumor thrombus--a case report].

For patients with multiple bilobar hepatocellular carcinoma (m-HCC) and/or advanced portal venous tumor thrombus (Vp3, 4), there has been no effective therapy, and the survival of more than 6 months was exceptional. Under these circumstances, we have developed a dual treatment (dual Tx) that combines reductive hepatectomy with percutaneous isolated hepatic perfusion (PIHP) for such patients. This dual Tx offers the high-rate of mid- and long-term survival in a subset of patients who had previously a dismal prognosis. Herein, we report a patient with Vp4 m-HCC who was successfully treated with dual Tx and survived for more than 2 years with a complete remission of hepatic tumors. A 53-year-old man had main tumors in the right lobe liver and multiple bilobar intrahepatic metastases (IM) with portal venous tumor thrombus reaching the portal trunk. He underwent an extended right hepatectomy with portal venous tumor thrombectomy, and subsequently PIHP twice in a 3-month period after reductive hepatectomy. After dual Tx, he had sustained complete remission for more than 2 years. He died because of obstruction of the superior vena cava by recurrent tumors in the mediastinum. His clinical course after treatment strongly indicates that the dual Tx should become a major treatment option for patients with Vp3, 4 m-HCC.

Carcinoma, Hepatocellular↗
PubMed2005

[A case of multiple hepatocellular carcinoma with rapidly progressing bilateral portal vein tumor thrombosis--a complete remission achieved with dual treatment of reductive surgery plus percutaneous isolated hepatic perfusion].

We herein report a case of multiple advanced hepatocellular carcinoma (HCC) with rapidly progressing portal vein tumor thrombosis (PVTT). All of the hepatic tumors have completely disappeared for more than two years by a dual treatment with reductive surgery plus percutaneous isolated hepatic perfusion (PIHP). A 55-year-old man was referred to our institution on June 30, 2003. The abdominal CT scan demonstrated multiple massive HCC in the entire liver with PVTT reaching the portal trunk (Vp4). Two weeks later, the PVTT rapidly progressed to the umbilical portion of the left portal vein, and to the confluence of the superior mesenteric vein and to the splenic vein. Thus, we semi electively performed an extended right hepatectomy together with thrombectomy of the PVTT. Subsequently, he underwent a repeated PIHP (1st; doxorubicin 90 mg/m2, 2nd doxorubicin 65 mg/m2). This treatment produced complete tumor clearance of all of the residual tumors in the left liver. In March 2005, he underwent partial pneumonectomy for a metastatic lung. This again resulted in normalization of serum AFP and PIVKA-II levels. Dual treatment is considered to be the strongest therapeutic modality for multiple advanced HCC with severe PVTT. In addition, a close follow-up is required because in such far advanced cases, metastatic lesions most likely recur in the liver but also in the distant organs.

Carcinoma, Hepatocellular↗
PubMed2004

Reductive surgery plus percutaneous isolated hepatic perfusion for multiple advanced hepatocellular carcinoma.

OBJECTIVE: To evaluate the efficacy of a novel 2-stage treatment with reductive surgery plus percutaneous isolated hepatic perfusion (PIHP) for multiple hepatocellular carcinoma (HCC), which was previously unresectable. SUMMARY BACKGROUND DATA: Surgical resection is the treatment of choice for HCC, but the majority of patients with advanced HCC are not suitable candidates. PIHP is a minimally invasive surgery that allows high-dose regional chemotherapy of the liver, and our phase II studies have shown its profound efficacy for the local control of advanced HCC. METHODS: Twenty-five patients with multiple advanced HCC were enrolled in this prospective study. In the first stage, all patients underwent reductive hepatectomy: major hepatectomy in 13 patients and segmentectomy or less in 12. In 2 patients with subsegmentectomy, the retropancreatic and periportal metastatic lymph nodes were synchronously resected. Regardless of the type of hepatectomy, all patients routinely underwent cholecystectomy, and ligations of the right gastric artery and arterial collaterals of the remnant liver to increase the safety and efficacy of PIHP. In the second stage, PIHP with doxorubicin 60-120 mg/m2/treatment was planned for a period of 1 to 3 months after surgery. RESULTS: Of 25 enrolled patients, 22 successfully underwent PIHP an average of 1.8 times for the local control of residual liver tumors. In the remaining 3 patients, PIHP was abandoned because 2 had rapid disease progression and 1 had liver failure after surgery. In 22 patients with the 2-stage treatment, 19 (86%) had objective local tumor control (10 complete remissions and 9 partial responses with a median response duration of 16 months). The actuarial survival rate of all 25 patients was 42% at 5 years. CONCLUSIONS: Reductive surgery plus PIHP produced a strong antitumoral effect on multiple advanced HCC, when liver function allows this concentrated treatment approach, and offers long-term survival in a subset of patients who were previously deemed to have unresectable disease.

Adult↗
PubMed2003

Significant role of middle hepatic vein in remnant liver regeneration of right-lobe living donors.

For adult patients with end-stage liver disease, living-donor liver transplantation (LDLT) of right-lobe grafts with or without the middle hepatic vein (MHV) has been increasingly used in recent years. We investigated the role of the MHV in donor remnant liver regeneration after right-lobe LDLT, which has not been described in previous studies. A total of eight living donors were included in this study of right-lobe LDLT. Four donors underwent right lobectomy (without MHV), and the remaining four underwent extended right lobectomy (with MHV). Regeneration of the donor remnant liver was assessed by volumetric computed tomography studies before and 90 days after LDLT. Comparison between the right-lobe and extended right-lobe donors did not show a clear-cut difference in the net increase of remnant liver volume at 3 months. However, the mean volume increase of the medial segment at the 90th postoperative day was 7% in the extended right-lobe donors and 61% in the right-lobe donors, showing a lower value in the remnant livers without MHV. The MHV plays a specific role in remnant liver regeneration of right-lobe living donors. We expect that this knowledge will contribute to securing a margin of safety in right-lobe LDLT.

Adult↗
PubMed2003

Open-biopsy-forceps technique for endoscopic removal of distally migrated and impacted biliary metallic stents.

BACKGROUND: Endoscopic removal of distally migrated and impacted biliary metallic stents is technically challenging. An open-biopsy-forceps technique for endoscopic removal of these migrated stents is described. METHODS: The technique was used in 4 patients with distally migrated and impacted covered metallic stents. A closed biopsy forceps was advanced through the stent mesh and opened within the stent to form an "anchor." With endoscope withdrawal, the stent was dislodged easily from the duodenum to the stomach. After grasping an end of the stent with a snare, the stent was removed by complete withdrawal of the endoscope. OBSERVATIONS: In all patients, the impacted stent was removed successfully. Mean time for removal was 10.2 minutes. Although ulceration was evident in the duodenal wall where the distal stent end was impacted in all patients, no other complication or adverse event was observed. CONCLUSIONS: The open-biopsy-forceps technique is useful for endoscopic removal of distally migrated and impacted biliary metallic stents.

Aged↗
PubMed2001

Critical function of the Ras-associating domain as a primary Ras-binding site for regulation of Saccharomyces cerevisiae adenylyl cyclase.

Mammalian candidate effectors of the small GTPase Ras, such as RalGDS, afadin/AF-6, Rin1, and phospholipase Cepsilon, have been shown to share structurally conserved modules termed Ras-associating (RA) domains at their Ras-binding sites. The Ras-binding domains of Raf-1 and phosphoinositide 3-kinase gamma (other Ras effectors) also share a similar tertiary structure with the RA domains. On the other hand, the primary Ras-binding site of Saccharomyces cerevisiae adenylyl cyclase, the best characterized Ras effector, has been mapped by mutational studies to the leucine-rich repeats (LRR) domain (amino acids 674-1300), whose structure apparently bears no resemblance to the RA domains. By a computer algorithm-based search we have unexpectedly found an RA domain in the N-terminal 81 amino acid residues (676) of the LRR domain. The purified RA-domain polypeptide exhibits an ability to bind directly to Ras in a GTP-dependent manner and to competitively inhibit Ras-dependent activation of adenylyl cyclase in vitro, with an affinity comparable with that of the whole LRR domain. The specificity of binding of the RA domain to various Ras effector region mutants is indistinguishable from that of the full-length adenylyl cyclase. The activated RAS2 (RAS2(Val-19))-dependent heat shock sensitivity of yeast cells is suppressed by overexpression of the RA domain polypeptide. Further, mutations of the RA domain abolish its Ras binding activity, and adenylyl cyclase molecules carrying these mutations are rendered unactivatable by Ras in vitro. This RA domain bears highest similarity to the Ras-binding domain of Raf-1 based on comparison of its primary and predicted secondary structures with those of other Ras effectors. These results indicate that the RA domain is a primary Ras-binding site for activation of adenylyl cyclase, implicating RA domains as universal modules for interaction of effectors with Ras, conserved from yeast to mammals.

Adenylyl Cyclases↗